Objective: To explore the possible factors influencing lumbar spinal bone mineral contents and bone mineral densities in Chinese adolescents with early ankylosing spondylitis(AS). Methods: Thirty-one male Chinese adol...Objective: To explore the possible factors influencing lumbar spinal bone mineral contents and bone mineral densities in Chinese adolescents with early ankylosing spondylitis(AS). Methods: Thirty-one male Chinese adolescent outpatients with early AS were included and compared with 31 age-matched male controls. Age (year), height (cm), total body weight (kg) together with body mass index (BMI, kg/m 2) of all subjects and disease duration (month), BASMI, BASFI, BASDAI, SASSS as well as ESR (mm/h) of AS patients were obtained. Lumbar 2-4 bone mineral content (L 2-4BMC, g) and lumbar 2-4 areal bone mineral density (L 2-4 BMD, g/cm 2) were evaluated using dual-energy X-ray absorptiometry (DEXA) with Lunar DPX-IQ device and lumbar 2-4 volumetric bone mineral apparent density (L 2-4 BMAD, g/cm 3) was subsequently calculated. Correlation and multiple regression analyses were performed. Results: Compared with 31 age-matched male controls, AS patients had significantly lower L 2-4BMD [(0.984±0.142) g/cm 2 vs (1.055±0.137) g/cm 2, P=0.049] and L 2-4BMAD [(0.1527±0.0173) g/cm 3 vs (0.1630±0.0195) g/cm 3, P=0.032]. In AS patients, multiple regression analysis identified that only the factor of height was significantly correlated with L 2-4BMC (R=0.673, P=0.000) and the factor of weight had predominant influences on L 2-4BMD (R=0.620, P=0.000) as well as L 2-4BMAD (R=0.510, P=0.003). Conclusion: The young patients with early AS had marked reduction in lumbar spine bone mineral densities, which indicated an important primary event leading to osteoporosis. Positive effects of height and weight on lumbar spine bone mass and densities could expectantly make favorable contributions to early prevention of AS associated bone loss and subsequent osteoporosis.展开更多
BACKGROUND Type 2 diabetes mellitus(T2DM),a fast-growing issue in public health,is one of the most common chronic metabolic disorders in older individuals.Osteoporosis and sarcopenia are highly prevalent in T2DM patie...BACKGROUND Type 2 diabetes mellitus(T2DM),a fast-growing issue in public health,is one of the most common chronic metabolic disorders in older individuals.Osteoporosis and sarcopenia are highly prevalent in T2DM patients and may result in fractures and disabilities.In people with T2DM,the association between nutrition,sarcopenia,and osteoporosis has rarely been explored.AIM To evaluate the connections among nutrition,bone mineral density(BMD)and body composition in patients with T2DM.METHODS We enrolled 689 patients with T2DM for this cross-sectional study.All patients underwent dual energy X-ray absorptiometry(DXA)examination and were categorized according to baseline Geriatric Nutritional Risk Index(GNRI)values calculated from serum albumin levels and body weight.The GNRI was used to evaluate nutritional status,and DXA was used to investigate BMD and body composition.Multivariate forward linear regression analysis was used to identify the factors associated with BMD and skeletal muscle mass index.RESULTS Of the total patients,394 were men and 295 were women.Compared with patients in tertile 1,those in tertile 3 who had a high GNRI tended to be younger and had lower HbA1c,higher BMD at all bone sites,and higher appendicular skeletal muscle index(ASMI).These important trends persisted even when the patients were divided into younger and older subgroups.The GNRI was positively related to ASMI(men:r=0.644,P<0.001;women:r=0.649,P<0.001),total body fat(men:r=0.453,P<0.001;women:r=0.557,P<0.001),BMD at all bone sites,lumbar spine(L1-L4)BMD(men:r=0.110,P=0.029;women:r=0.256,P<0.001),FN-BMD(men:r=0.293,P<0.001;women:r=0.273,P<0.001),and hip BMD(men:r=0.358,P<0.001;women:r=0.377,P<0.001).After adjustment for other clinical parameters,the GNRI was still significantly associated with BMD at the lumbar spine and femoral neck.Additionally,a low lean mass index and higherβ-collagen special sequence were associated with low BMD at all bone sites.Age was negatively correlated with ASMI,whereas weight was positively correlated with ASMI.CONCLUSION Poor nutrition,as indicated by a low GNRI,was associated with low levels of ASMI and BMD at all bone sites in T2DM patients.Using the GNRI to evaluate nutritional status and using DXA to investigate body composition in patients with T2DM is of value in assessing bone health and physical performance.展开更多
Background: When applied to trabecular bone X-ray images, the anisotropic properties of trabeculae located at ultra-distal radius were investigated by using the trabecular bone scores (TBS) calculated along directions...Background: When applied to trabecular bone X-ray images, the anisotropic properties of trabeculae located at ultra-distal radius were investigated by using the trabecular bone scores (TBS) calculated along directions parallel and perpendicular to the forearm. Methodology: Data from more than two hundred subjects were studied retrospectively. A DXA (GE Lunar Prodigy) scan of the forearm was performed on each subject to measure the bone mineral density (BMD) value at the location of ultra-distal radius, and an X-ray digital image of the same forearm was taken on the same day. The values of trabecular bone score along the direction perpendicular to the forearm, TBS<sub>x</sub>, and along the direction parallel to the forearm, TBS<sub>y</sub>, were calculated respectively. The statistics of TBS<sub>x</sub> and TBS<sub>y</sub> were calculated, and the anisotropy of the trabecular bone, which was defined as the ratio of TBS<sub>y</sub> to TBS<sub>x</sub> and changed with subjects’ BMD and age, was reported and analyzed. Results: The results show that the correlation coefficient between TBS<sub>x</sub> and TBS<sub>y</sub> was 0.72 (p BMD and age was reported. The results showed that decreased trabecular bone anisotropy was associated with deceased BMD and increased age in the subject group. Conclusions: This study shows that decreased trabecular bone anisotropy was associated with decreased BMD and increased age.展开更多
Background:Areal bone mineral density(aBMD)applied for osteoporosis diagnosis unavoidably results in the missingdiagnosis in patients with large bones and misdiagnosis in those with small bones.Therefore,we try to fin...Background:Areal bone mineral density(aBMD)applied for osteoporosis diagnosis unavoidably results in the missingdiagnosis in patients with large bones and misdiagnosis in those with small bones.Therefore,we try to find a new adjusted index of bone mineral content(BMC)to make up shortcomings of aBMD in osteoporosis diagnosis.Methods:In this multi-center epidemiological study,BMC and aBMD of lumbar spines(n=5510)and proximal femurs(n=4710)were measured with dual energy X-ray absorptiometry(DXA).We analyzed the correlation between the bone mass and body weight in all subjects including four age groups(<19 years,20-39 years,40-49 years,>50 years).And then the body weight was used for standardizing BMC(named wBMC)and applied for the epidemiological analysis of osteoporosis?Results:The correlation of body weight and BMC is 0.839 to 0.931 of lumbar vertebra 1-4(Li_4),and 0.71 to 0.95 of femoral neck in different age groups.When aBMD was applied for diagnosing osteoporosis,the prevalence was 7.55%,16.39%,and 25.83%in patients with a high,intermediate,and low body weight respectively.However,the prevalence was 21.8%,18.03%,and 11.64%by wBMC applied for diagnosing osteoporosis.Moreover,the prevalence of osteoporosis increased by 3.76%by wBMC with the body weight increased by 5 kg.The prevalence decreased by 1.94%when the body weight decreased by 5 kg.Conclusions:wBMC can reduce the missed diagnosis in patients with large body weight and reduce misdiagnosis in those with small body weight.Including children,wBMC may be feasible for osteoporosis diagnosis individuals at any age.展开更多
Purpose: Obtaining high peak bone mass (PBM) and maintaining bone mass is important for the prevention of osteoporosis. This study aimed to examine the regional differences in bone mineral density and factors associat...Purpose: Obtaining high peak bone mass (PBM) and maintaining bone mass is important for the prevention of osteoporosis. This study aimed to examine the regional differences in bone mineral density and factors associated with its acquisition from exercise. Design: The study population included 75 women of 18 - 22 years of age in East Japan and 104 women of 18 - 27 years of age in West Japan. The speed of sound (SOS) of the calcaneus was measured, and the young adult mean (%YAM) was calculated from the SOS. The subjects’ medical history, family history of osteoporosis, and exercise habits were examined using a self-administered questionnaire. Results: There were a significantly greater number of subjects with low %YAM in West Japan. The exercise history and exercise time were significantly higher in West Japan, and the exercise intensity score tended to be higher in East Japan during junior high and high school. A multiple regression analysis by region revealed that the following factors had a significant positive association with the SOS: exercise intensity at elementary school and outdoor sports at junior high school in East Japan;and exercise time at elementary school, muscle mass, and outdoor sports at junior high school in West Japan. On the other hand, exercise time in junior high school in West Japan showed a negative association with the SOS. Conclusions: Regional differences in bone mineral density existed, suggesting a trend toward lower bone mineral density in West Japan. Exercise history and time tended to be higher in West Japan, and exercise intensity scores tended to be higher in East Japan, suggesting that exercise intensity may be more important than exercise time for obtaining bone mineral density.展开更多
Objective: To understand the correlation between different degrees of obesity and bone mineral density (BMD). Methods: 772 cases (300 men and 472 females) of Zhuang over 40 years old were randomly selected. The BMD an...Objective: To understand the correlation between different degrees of obesity and bone mineral density (BMD). Methods: 772 cases (300 men and 472 females) of Zhuang over 40 years old were randomly selected. The BMD and T score were calculated by measuring the right heel bone using a quantitative-ultrasound densitometer. Body composition index of body weight, waist circumference (WC), waist height ratio (WtHR), body fat percentage (BFP) and visceral fat (VF) were measured using a bioelectrical impedance method. Results: The BMI, WC, and WtHR of the male osteoporosis group were lower than those of the normal bone mass (NBM) group (P Conclusion: BMI is positively correlated with BMD in Zhuang. BFP has a greater correlation with female BMD, and a small reduction in BFP can result in a significant decrease in BMD. BMD of male was positively correlated with abdominal obesity indicators (WC, WtHR, VF). However, abdominal obesity has no obvious effect on the promotion of BMD in women, and increased WtHR can lead to a decrease in BMD. Zhuang can appropriately increase the amount of fat within the normal weight range. At the same time, reasonable exercise and balanced nutrition to avoid excessive obesity or low body weight can reduce the incidence of osteoporosis and osteoporosis fractures.展开更多
Bone is a complex but orderly mineralized tissue with hydroxyapatite(HA)as the inorganic phase and collagen as the organic phase.Inspired by natural bone tissues,HA-mineralized hydrogels have been widely designed and ...Bone is a complex but orderly mineralized tissue with hydroxyapatite(HA)as the inorganic phase and collagen as the organic phase.Inspired by natural bone tissues,HA-mineralized hydrogels have been widely designed and used in bone tissue engineering.HA is majorly utilized for the treatment of bone defects because of its excellent osteoconduction and bone inductivity.Hydrogel is a three-dimensional hydrophilic network structure with similar properties to the extracellular matrix(ECM).The combination of HA and hydrogels produces a new hybrid material that could effectively promote osteointegration and accelerate the healing of bone defects.In this review,the structure and growth of bone and the common strategies used to prepare HA were briefly introduced.Importantly,we discussed the fabrication of HA mineralized hydrogels from simple blending to in situ mineralization.We hope this review can provide a reference for the development of bone repair hydrogels.展开更多
Persistent generalized low bone mineral density (BMD) has been reported in patients with adolescent idiopathic scoliosis (AIS).However,the exact mechanisms and causes of the low BMD in AIS patients are largely unknown...Persistent generalized low bone mineral density (BMD) has been reported in patients with adolescent idiopathic scoliosis (AIS).However,the exact mechanisms and causes of the low BMD in AIS patients are largely unknown.The purpose of this study was to examine the relationship between the receptor activator of NF-κB ligand (RANKL)/osteoprotegerin (OPG) levels in osteoblasts (OBs) from AIS patients with low BMD and with comparison made between the patients and controls.Twenty AIS patients and eight age-matched controls were included in the present study.The BMD of lumbar spine and proximal femur was measured in all subjects.OBs from the cancellous bone of each subject was harvested and primarily cultured.The mRNA and protein expression of RANKL and OPG in OBs was detected by RT-PCR and Western blotting.The results showed BMD was lower in AIS patients than in controls.A significantly higher mRNA and protein expression of RANKL was observed in OBs from AIS patients,while no significant difference was found in the expression of OPG between AIS patients and controls.As a result,RANKL/OPG ratio in patients with AIS was remarkably higher than controls.Our study preliminarily demonstrated expression of RANKL was higher in OBs from AIS patients with low BMD as compared with controls,suggesting the unbalanced RANKL/OPG ratio caused by an over-expression of RANKL in OBs may be responsible for the low BMD in AIS patients.展开更多
AIM: To investigate bone mineral density (BMD) in obese children with and without nonalcoholic fatty liver disease (NAFLD); and the association between BMD and serum adipokines, and high-sensitivity C-reactive protein...AIM: To investigate bone mineral density (BMD) in obese children with and without nonalcoholic fatty liver disease (NAFLD); and the association between BMD and serum adipokines, and high-sensitivity C-reactive protein (HSCRP). METHODS: A case-control study was performed. Cases were 44 obese children with NAFLD. The diagnosis of NAFLD was based on magnetic resonance imaging (MRI) with high hepatic fat fraction (≥ 5%). Other causes of chronic liver disease were ruled out. Controls were selected from obese children with normal levels of aminotransferases, and without MRI evidence of fatty liver as well as of other causes of chronic liver diseases. Controls were matched (1-to 1-basis) with thecases on age, gender, pubertal stage and as closely as possible on body mass index-SD score. All participants underwent clinical examination, laboratory tests, and whole body (WB) and lumbar spine (LS) BMD by dual energy X-ray absorptiometry. BMDZ-scores were calcu- lated using race and gender specific LMS curves. RESULTS: Obese children with NAFLD had a significantly lower LS BMDZ-score than those without NAFLD [mean, 0.55 (95%CI: 0.23-0.86) vs 1.29 (95%CI: 0.95-1.63); P < 0.01]. WB BMD Z-score was also decreased in obese children with NAFLD compared to obese children with no NAFLD, though borderline significance was observed [1.55 (95%CI: 1.23-1.87) vs 1.95 (95%CI: 1.67-2.10); P = 0.06]. Children with NAFLD had significantly higher HSCRP, lower adiponectin, but similar leptin levels. Thirty five of the 44 children with MRI-diagnosed NAFLD underwent liver biopsy. Among the children with biopsy-proven NAFLD, 20 (57%) had nonalcoholic steatohepatitis (NASH), while 15 (43%) no NASH. Compared to children without NASH, those with NASH had a significantly lower LS BMD Z-score [mean, 0.27 (95%CI: -0.17-0.71) vs 0.75 (95%CI: 0.13-1.39); P < 0.05] as well as a significantly lower WB BMD Z-score [1.38 (95%CI: 0.89-1.17) vs 1.93 (95%CI: 1.32-2.36); P < 0.05]. In multiple regression analysis, NASH (standardized β coefficient, -0.272; P < 0.01) and HSCRP (standardized β coefficient, -0.192; P < 0.05) were significantly and independently associated with LS BMD Z-score. Similar results were obtained when NAFLD (instead of NASH) was included in the model. WB BMD Z-scores were significantly and independently associated with NASH (standardized β coefficient, -0.248;P < 0.05) and fat mass (standardized β coefficient, -0.224;P < 0.05). CONCLUSION: This study reveals that NAFLD is associated with low BMD in obese children, and that systemic, low-grade inflammation may accelerate loss of bone mass in patients with NAFLD.展开更多
BACKGROUND The inflammatory bowel diseases(IBD),Crohn’s disease(CD)and ulcerative colitis(UC)are chronic,immune-mediated disorders of the digestive tract.IBD is considered to be a risk factor for developing osteoporo...BACKGROUND The inflammatory bowel diseases(IBD),Crohn’s disease(CD)and ulcerative colitis(UC)are chronic,immune-mediated disorders of the digestive tract.IBD is considered to be a risk factor for developing osteoporosis;however current literature on this matter is inconsistent.AIM To assess prevalence and development of osteoporosis and low bone mineral density(BMD),and its risk factors,in IBD patients.METHODS Systematic review of population-based studies.Studies were identified by electronic(January 2018)and manual searches(May 2018).Databases searched included EMBASE and PubMed and abstracts from 2014-2018 presented at the United European Gastroenterology Week,the European Crohn’s and Colitis Organisation congress,and Digestive Disease Week were screened.Studies were eligible for inclusion if they investigated either the prevalence of osteoporosis or osteopenia and/or risk factors for osteoporosis or low BMD in IBD patients.Studies on children under the age of 18 were excluded.Only population-based studies were included.All risk factors for osteoporosis and low BMD investigated in any included article were considered.Study quality and the possibility of bias were analysed using the Newcastle-Ottawa scale.RESULTS Twelve studies including 3661 IBD patients and 12789 healthy controls were included.Prevalence of osteoporosis varied between 4%-9%in studies including both CD and UC patients;2%-9% in studies including UC patients, and 7%-15% instudies including CD patients. Among healthy controls, prevalence ofosteoporosis was 3% and 10% in two studies. CD diagnosis, lower body massindex (BMI), and lower body weight were risk factors associated withosteoporosis or low BMD. Findings regarding gender showed inconsistent results.CD patients had an increased risk for osteoporosis or low BMD over time, whileUC patients did not. Increased age was associated with decreased BMD, and therewas a positive association between weight and BMI and BMD over time. Greatheterogeneity was found in the included studies in terms of study methodologies,definitions and the assessment of osteoporosis, and only a small number ofpopulation-based studies was available.CONCLUSIONThis systematic review found a possible increase of prevalence of osteoporosis inCD cohorts when compared to UC and cohorts including both disease types.Lower weight and lower BMI were predictors of osteoporosis or low BMD in IBDpatients. The results varied considerably between studies.展开更多
Cone beam computed tomography(CBCT) has often been used to determine the quality of craniofacial bone structures through the determination of mineral density, which is based on gray scales of the images obtained. Howe...Cone beam computed tomography(CBCT) has often been used to determine the quality of craniofacial bone structures through the determination of mineral density, which is based on gray scales of the images obtained. However, there is no consensus regarding the accuracy of the determination of the gray scales in these exams. This study aims to provide a literature review concerning the reliability of CBCT to determine bone mineral density. The gray values obtained with CBCT show a linear relationship with the attenuation coefficients of the materials, Hounsfield Units values obtained with medical computed tomography, and density values from dual energy X-ray absorciometry. However, errors are expected when CBCT images are used to define the quality of the scanned structures be-cause these images show inconsistencies and arbitrari-ness in the gray values, particularly when related to abrupt change in the density of the object, X-ray beam hardening effect, scattered radiation, projection data discontinuity-related effect, differences between CBCTdevices, changes in the volume of the field of view(FOV), and changes in the relationships of size and position between the FOV and the object evaluated. A few methods of mathematical correction of the gray scales in CBCT have been proposed; however, they do not generate consistent values that are independent of the devices and their configurations or of the scanned objects. Thus, CBCT should not be considered the ex-amination of choice for the determination of bone and soft tissue mineral density at the current stage, par-ticularly when values obtained are to be compared to predetermined standard values. Comparisons between symmetrically positioned structures inside the FOV and in relation to the exomass of the object, as it occurs with the right and left sides of the skull, seem to be viable because the effects on the gray scale in the re-gions of interest are the same.展开更多
Determination of dry bulk density and water content measurement of magnetic susceptibility (x) and saturation isothermal remanent magnetization (SIRM), determination of carbonate content, and determination of total or...Determination of dry bulk density and water content measurement of magnetic susceptibility (x) and saturation isothermal remanent magnetization (SIRM), determination of carbonate content, and determination of total organic carbon (TOC) content nitrogen content (N%) and carbon/nitrogen (C/N) ratio are some of the techniques which have been widely applied to lacustrine-sediment analyses. The techniques,complemented by others, are usually useful for revealing characteristics of lacustrine-sediments and thus for postulating hydrological regimes in the lake and environmental conditions and human activity around it in palaeolimnological studies. A very brief review is presented on recent applications of these techniques in palaeolimnological work with English literatures published mainly since 1985 and focus given on interpretations of results of these analyses related to palaeoenvironmental reconstructions. Low dry bulk density and high water content often imply relatively warm and wet conditions. High X and SIRM are usually resulted from reduced dilutions in the lake and intensified erosions on its catchment. both of which can be in turn attributed to environmental changes. While variations in patterns of X and SIRM may give further insight on mineral magnetism and thus implications on environmental conditions. Increased carbonate content seems likely to associate to warm and dry conditions.Increased TOC content is virtually used as one of indicators of warm and wet conditions and variations in C/N ratio may hint variations in relative contributions of different sources, aquatic and terrestrial, to the total organic matter in lake sediments and hence to lake-level fluctuations and climate changes.展开更多
Phytic acid is the principal storage form of phosphorus in plant seeds and an essential signalling molecule in several regulatory processes of plant development.However,it is known as an anti-nutrient compound owing t...Phytic acid is the principal storage form of phosphorus in plant seeds and an essential signalling molecule in several regulatory processes of plant development.However,it is known as an anti-nutrient compound owing to its potent chelating property.Thus,reducing the phytic acid content in crops is desirable.Studies involving regulation of MIPS and IPK1 genes to generate low phytate rice have been reported earlier.However,the functional significance of OsITPK and the effect of its down-regulation on phytic acid content and the associated pleiotropic effects on rice have not yet been investigated.In this study,tissue specific RNA interference(RNAi)-mediated down-regulation of a major ITPK homolog(OsITP5/6K-1)resulted in 46.2%decrease in phytic acid content of T2 transgenic seeds with a subsequent 3-fold enhancement in the inorganic phosphorus content.Silencing of OsITP5/6K-1 altered the transcript levels of essential phytic acid pathway genes,without significantly affecting the transcript levels of other OsITPK homologs.Furthermore,the mapping of elements through X-ray microfluorescence analysis revealed significant changes in the spatial distribution pattern and translocation of elements in low phytate seeds.Additionally,low phytate polished seeds exhibited 1.3-fold and 1.6-fold enhancement in iron and zinc content in the grain endosperm,respectively.Silencing of OsITP5/6K-1 also altered the amino acid and myo-inositol content of the transgenic seeds.Our results successfully established that RNAi-mediated silencing of OsITP5/6K-1 gene significantly reduced the phytate levels in seeds without hampering the germination potential of seeds and plant growth.The present study provided an insight into the mechanism of phytic acid biosynthesis pathway.展开更多
BACKGROUND Diabetes is a chronic disease,which may cause various complications.Patients with diabetes are at high risk of bone and joint disorders,such as osteoporosis and bone fractures.In addition,it became widely a...BACKGROUND Diabetes is a chronic disease,which may cause various complications.Patients with diabetes are at high risk of bone and joint disorders,such as osteoporosis and bone fractures.In addition,it became widely accepted that diabetes has an important impact on bone metabolism.Metformin is a commonly used and effective first-line treatment for type 2 diabetes.Some glucose-lowering agents have been found to have an effect on bone metabolism.The present study explored if different doses of metformin have an effect on bone mineral density(BMD)and bone metabolism in type 2 diabetes.AIM To investigate the effects of different doses of metformin on BMD and bone metabolism in elderly male patients with type 2 diabetes mellitus.METHODS A total of 120 elderly male outpatients with type 2 diabetes mellitus who were admitted to our hospital were included in the study from July 2018 to June 2019.They were randomly assigned to an experimental group and a control group with 60 patients in each group.Patients in the experimental group were given high dose metformin four times a day 0.5 g each time for 12 wk.Patients in the control group were given low dose metformin orally twice a day 0.5 g each time for 12 wk.The changes in bone mineral density and bone metabolism before and after treatment and the efficacy rate of the treatment were compared between the two groups.RESULTS There was no significant difference in the efficacy rate between the two groups(P>0.05).Before the treatment,there was no significant difference in BMD and bone metabolism between the two groups(P>0.05).However,after the treatment,BMD and bone metabolism were improved in the two groups.Moreover,BMD and 25-hydroxyvitamin D were significantly higher in the experimental group than in the control group,and N-terminal/midregion andβ-isomerized Cterminal telopeptides were significantly lower in the experimental group than in the control group(all P<0.05).There was no significant difference in the incidence of adverse reactions between the two groups(P>0.05).CONCLUSION Both high and low dose metformin can effectively control the blood glucose levels in elderly male patients with type 2 diabetes mellitus.However,the benefits of high dose metformin in improving BMD and bone metabolism level was more obvious in patients with type 2 diabetes mellitus.展开更多
The aim of this study was to determine the relationship between obesity and osteoporosis. A total of 30 Saudi women, aged between 20 and 50 years, were selected randomly. We calculated each subject’s body mass index ...The aim of this study was to determine the relationship between obesity and osteoporosis. A total of 30 Saudi women, aged between 20 and 50 years, were selected randomly. We calculated each subject’s body mass index (BMI) and determined their lumbar and femur bone mineral densities using dual-energy X-ray absorptiometry (DXA). We examined the interaction between obesity and bone mineral density (BMD) using logistic regression, after adjusting for age, family history of osteoporosis, maternal fractures, smoking, and any sedentary lifestyles. BMI was shown to be the most effective independent variable with respect to bone density. We evaluated the Pearson correlation coefficients of BMI, BMD of the lumbar spine, and BMD of the femoral neck with reference to the variables of the study, and found a significant correlation (P 30 kg/m2) were at increased risk of osteoporosis at the femoral neck and severe osteopenia in the lumbar spine.展开更多
Sorghum is an important staple food crop of Asian and African countries.As a poor man s crop",it provides dietary starch,protein,and some vitamins and minerals.Minerals are important for various physiological fun...Sorghum is an important staple food crop of Asian and African countries.As a poor man s crop",it provides dietary starch,protein,and some vitamins and minerals.Minerals are important for various physiological functions in the human body.As a major staple crop of central and southern Indian provinces,sorghum landraces are a source of supplementary micronutrients.Concentrations of micronutrients and protein and yield parameters were studied using 112 local landraces and varieties.Univariate analysis revealed wide variation for iron(1.10-9.54 mg 100 g^(-1)),zinc(1.12-7.58 mg 100 g^(-1)),protein(3.50-12.60%),and grain yield(2.50-76.50 g) among the landraces.High estimates of genetic/phenotypic coefficient of variation,and genetic advances over the mean were identified for landraces and varieties.High heritabilities were also identified for yield and mineral content.Correlation estimates among the genotypes indicated that grain yield was positively correlated with copper and protein with copper and zinc.Cluster analysis based on Euclidean distance resolved all of the genotypes into three major clusters.The wide range of values with high heritability estimates may favor the use of these landraces in recombination breeding to improve nutritional quality in sorghum.展开更多
AIM:To estimate the prevalence and identify the risk factors for metabolic bone disease in patients with cirrhosis.METHODS:The study was performed on 72 Indian patients with cirrhosis(63 male, 9 female;aged < 50 ye...AIM:To estimate the prevalence and identify the risk factors for metabolic bone disease in patients with cirrhosis.METHODS:The study was performed on 72 Indian patients with cirrhosis(63 male, 9 female;aged < 50 years).Etiology of cirrhosis was alcoholism(n = 37), hepatitis B(n = 25) and hepatitis C(n = 10).Twenty-three patients belonged to Child class A, while 39 were in class B and 10 in class C.Secondary causes for metabolic bone disease and osteoporosis were ruled out.Sunlight exposure, physical activity and dietary constituents were calculated.Complete metabolic profiles were derived, and bone mineral density(BMD) was measured using dual energy X ray absorptiometry.Low BMD was defined as a Z score below-2.RESULTS:Low BMD was found in 68% of patients.Lumbar spine was the most frequently and severely affected site.Risk factors for low BMD included low physical activity, decreased sunlight exposure, and low lean body mass.Calcium intake was adequate, with unfavorable calcium:protein ratio and calcium:phosphorus ratio.Vitamin D deficiency was highly prevalent(92%).There was a high incidence of hypogonadism(41%).Serum estradiol level was elevated significantly in patients with normal BMD.Insulin-like growth factor(IGF) 1 and IGF binding protein 3 levels were below the age-related normal range in both groups.IGF-1 was signiflcantly lower in patients with low BMD.Serum osteocalcin level was low(68%) and urinary deoxypyridinoline to creatinine ratio was high(79%), which demonstrated low bone formation with high resorption.CONCLUSION:Patients with cirrhosis have low BMD.Contributory factors are reduced physical activity, low lean body mass, vitamin D def iciency and hypogonadism and low IGF-1 level.展开更多
After successful kidney transplantation, accumulated waste products and electrolytes are excreted and regulatory hormones return to normal levels. Despite the improvement in mineral metabolites and mineral regulating ...After successful kidney transplantation, accumulated waste products and electrolytes are excreted and regulatory hormones return to normal levels. Despite the improvement in mineral metabolites and mineral regulating hormones after kidney transplantation,abnormal bone and mineral metabolism continues to present in most patients. During the first 3 mo, fibroblast growth factor-23(FGF-23) and parathyroid hormone levels decrease rapidly in association with an increase in 1,25-dihydroxyvitamin D production. Renal phosphate excretion resumes and serum calcium, if elevated before, returns toward normal levels. FGF-23 excess during the first 3-12 mo results in exaggerated renal phosphate loss and hypophosphatemia occurs in some patients. After 1 year, FGF-23 and serum phosphate return to normal levels but persistent hyperparathyroidism remains in some patients. The progression of vascular calcification also attenuates. High dose corticosteroid and persistent hyperparathyroidism are the most important factors influencing abnormal bone and mineral metabolism in long-term kidney transplant(KT) recipients. Bone loss occurs at a highest rate during the first 6-12 mo after transplantation. Measurement of bone mineral density is recommended in patients with estimated glomerular filtration rate > 30 mL/min. The use of active vitamin D with or without bisphosphonate is effective in preventing early post-transplant bone loss. Steroid withdrawal regimen is also beneficial in preservation of bone mass in long-term. Calcimimetic is an alternative therapy to parathyroidectomy in KT recipients with persistent hyperparathyroidism. If parathyroidectomy is required, subtotal to near total parathyroidectomy is recommended. Performing parathyroidectomy during the waiting period prior to transplantation is also preferred in patients with severe hyperparathyroidism associated with hypercalcemia.展开更多
The aim of this study was to compare the quality characteristics and mineral content of the fiber from male and female cashmere goats raised under different management systems. Male and female Raeini cashmere goats (&...The aim of this study was to compare the quality characteristics and mineral content of the fiber from male and female cashmere goats raised under different management systems. Male and female Raeini cashmere goats (<1.5 years of age, n = 48) were selected from flocks raised at a government breeding station or raised commercially under either rural or nomadic conditions. The staple length, cashmere fiber diameter, coefficient of variation for fiber diameter, percentage of cashmere in a fleece, percentage of guard hair in a fleece and cashmere tenacity averaged 4.6 ±0.1 cm, 18.0 ±0.1 m, 20.9 ± 0.4%, 66.1 ± 1.5%, 33.8 ± 1.5% and 1.8 ± 0.2 gf/tex, respectively. The sulfur, copper and zinc content of the cashmere averaged 2.8 ± 0.1%, 0.00065 ± 0.00002% and 0.01276 ± 0.00025%, respectively. Rearing method significantly affected staple length, coefficient of variation of fiber diameter, cashmere tenacity and copper content. Males had a higher coefficient of variation of fiber diameter and cashmere tenacity than females (P < 0.05).展开更多
Bone studies of HIV-infected children using dual X-ray absorptiometry (DXA) suggest bone mineral density (BMD) abnormalities. Pediatric studies are often performed using DXA instead of computed tomography (CT), which ...Bone studies of HIV-infected children using dual X-ray absorptiometry (DXA) suggest bone mineral density (BMD) abnormalities. Pediatric studies are often performed using DXA instead of computed tomography (CT), which accounts for 3-dimensional differences in bone size of growing children. We evaluated whether CT would match DXA measurements in this population. For this purpose, the BMD of 16 perinatally HIV-infected patients, ages 6 to 22 was assessed. Subjects were matched by age, gender, and race to controls. BMD was assessed via DXA and QCT. Clinical anthropometric data, body mass index, immunologic and virologic parameters and laboratory markers for osteoblastic and osteoclastic activity were performed. No statistically significant differences in age and anthropometric parameters between subjects and controls were found. Individual CT and DXA z-scores were significantly different when subjects were evaluated as a group (p = 0.0002) or when males and females were analyzed independently (p = 0.001 and 0.03). DXA z-scores were below 1 SD, while CT z-scores were above the mean. 31% of subjects were identified as having poor bone mineralization by DXA while none had osteopenia/osteoporosis by CT. There was no correlation between immunologic/virologic parameters and BMD by either method. Increased osteoclastic activity was noted in 10 patients receiving tenofovir. In summary, decreased BMD diagnosed by DXA in pediatric HIV-infected subjects was not confirmed by CT. Increased bone turnover in patients on tenofovir was suggested by laboratory markers. Prospective studies using CT as the imaging standard are needed for evaluation of bone mineral changes in HIV-infected children.展开更多
文摘Objective: To explore the possible factors influencing lumbar spinal bone mineral contents and bone mineral densities in Chinese adolescents with early ankylosing spondylitis(AS). Methods: Thirty-one male Chinese adolescent outpatients with early AS were included and compared with 31 age-matched male controls. Age (year), height (cm), total body weight (kg) together with body mass index (BMI, kg/m 2) of all subjects and disease duration (month), BASMI, BASFI, BASDAI, SASSS as well as ESR (mm/h) of AS patients were obtained. Lumbar 2-4 bone mineral content (L 2-4BMC, g) and lumbar 2-4 areal bone mineral density (L 2-4 BMD, g/cm 2) were evaluated using dual-energy X-ray absorptiometry (DEXA) with Lunar DPX-IQ device and lumbar 2-4 volumetric bone mineral apparent density (L 2-4 BMAD, g/cm 3) was subsequently calculated. Correlation and multiple regression analyses were performed. Results: Compared with 31 age-matched male controls, AS patients had significantly lower L 2-4BMD [(0.984±0.142) g/cm 2 vs (1.055±0.137) g/cm 2, P=0.049] and L 2-4BMAD [(0.1527±0.0173) g/cm 3 vs (0.1630±0.0195) g/cm 3, P=0.032]. In AS patients, multiple regression analysis identified that only the factor of height was significantly correlated with L 2-4BMC (R=0.673, P=0.000) and the factor of weight had predominant influences on L 2-4BMD (R=0.620, P=0.000) as well as L 2-4BMAD (R=0.510, P=0.003). Conclusion: The young patients with early AS had marked reduction in lumbar spine bone mineral densities, which indicated an important primary event leading to osteoporosis. Positive effects of height and weight on lumbar spine bone mass and densities could expectantly make favorable contributions to early prevention of AS associated bone loss and subsequent osteoporosis.
基金Supported by Social Development Projects of Nantong,No.MS22021008 and No.QNZ2022005.
文摘BACKGROUND Type 2 diabetes mellitus(T2DM),a fast-growing issue in public health,is one of the most common chronic metabolic disorders in older individuals.Osteoporosis and sarcopenia are highly prevalent in T2DM patients and may result in fractures and disabilities.In people with T2DM,the association between nutrition,sarcopenia,and osteoporosis has rarely been explored.AIM To evaluate the connections among nutrition,bone mineral density(BMD)and body composition in patients with T2DM.METHODS We enrolled 689 patients with T2DM for this cross-sectional study.All patients underwent dual energy X-ray absorptiometry(DXA)examination and were categorized according to baseline Geriatric Nutritional Risk Index(GNRI)values calculated from serum albumin levels and body weight.The GNRI was used to evaluate nutritional status,and DXA was used to investigate BMD and body composition.Multivariate forward linear regression analysis was used to identify the factors associated with BMD and skeletal muscle mass index.RESULTS Of the total patients,394 were men and 295 were women.Compared with patients in tertile 1,those in tertile 3 who had a high GNRI tended to be younger and had lower HbA1c,higher BMD at all bone sites,and higher appendicular skeletal muscle index(ASMI).These important trends persisted even when the patients were divided into younger and older subgroups.The GNRI was positively related to ASMI(men:r=0.644,P<0.001;women:r=0.649,P<0.001),total body fat(men:r=0.453,P<0.001;women:r=0.557,P<0.001),BMD at all bone sites,lumbar spine(L1-L4)BMD(men:r=0.110,P=0.029;women:r=0.256,P<0.001),FN-BMD(men:r=0.293,P<0.001;women:r=0.273,P<0.001),and hip BMD(men:r=0.358,P<0.001;women:r=0.377,P<0.001).After adjustment for other clinical parameters,the GNRI was still significantly associated with BMD at the lumbar spine and femoral neck.Additionally,a low lean mass index and higherβ-collagen special sequence were associated with low BMD at all bone sites.Age was negatively correlated with ASMI,whereas weight was positively correlated with ASMI.CONCLUSION Poor nutrition,as indicated by a low GNRI,was associated with low levels of ASMI and BMD at all bone sites in T2DM patients.Using the GNRI to evaluate nutritional status and using DXA to investigate body composition in patients with T2DM is of value in assessing bone health and physical performance.
文摘Background: When applied to trabecular bone X-ray images, the anisotropic properties of trabeculae located at ultra-distal radius were investigated by using the trabecular bone scores (TBS) calculated along directions parallel and perpendicular to the forearm. Methodology: Data from more than two hundred subjects were studied retrospectively. A DXA (GE Lunar Prodigy) scan of the forearm was performed on each subject to measure the bone mineral density (BMD) value at the location of ultra-distal radius, and an X-ray digital image of the same forearm was taken on the same day. The values of trabecular bone score along the direction perpendicular to the forearm, TBS<sub>x</sub>, and along the direction parallel to the forearm, TBS<sub>y</sub>, were calculated respectively. The statistics of TBS<sub>x</sub> and TBS<sub>y</sub> were calculated, and the anisotropy of the trabecular bone, which was defined as the ratio of TBS<sub>y</sub> to TBS<sub>x</sub> and changed with subjects’ BMD and age, was reported and analyzed. Results: The results show that the correlation coefficient between TBS<sub>x</sub> and TBS<sub>y</sub> was 0.72 (p BMD and age was reported. The results showed that decreased trabecular bone anisotropy was associated with deceased BMD and increased age in the subject group. Conclusions: This study shows that decreased trabecular bone anisotropy was associated with decreased BMD and increased age.
文摘Background:Areal bone mineral density(aBMD)applied for osteoporosis diagnosis unavoidably results in the missingdiagnosis in patients with large bones and misdiagnosis in those with small bones.Therefore,we try to find a new adjusted index of bone mineral content(BMC)to make up shortcomings of aBMD in osteoporosis diagnosis.Methods:In this multi-center epidemiological study,BMC and aBMD of lumbar spines(n=5510)and proximal femurs(n=4710)were measured with dual energy X-ray absorptiometry(DXA).We analyzed the correlation between the bone mass and body weight in all subjects including four age groups(<19 years,20-39 years,40-49 years,>50 years).And then the body weight was used for standardizing BMC(named wBMC)and applied for the epidemiological analysis of osteoporosis?Results:The correlation of body weight and BMC is 0.839 to 0.931 of lumbar vertebra 1-4(Li_4),and 0.71 to 0.95 of femoral neck in different age groups.When aBMD was applied for diagnosing osteoporosis,the prevalence was 7.55%,16.39%,and 25.83%in patients with a high,intermediate,and low body weight respectively.However,the prevalence was 21.8%,18.03%,and 11.64%by wBMC applied for diagnosing osteoporosis.Moreover,the prevalence of osteoporosis increased by 3.76%by wBMC with the body weight increased by 5 kg.The prevalence decreased by 1.94%when the body weight decreased by 5 kg.Conclusions:wBMC can reduce the missed diagnosis in patients with large body weight and reduce misdiagnosis in those with small body weight.Including children,wBMC may be feasible for osteoporosis diagnosis individuals at any age.
文摘Purpose: Obtaining high peak bone mass (PBM) and maintaining bone mass is important for the prevention of osteoporosis. This study aimed to examine the regional differences in bone mineral density and factors associated with its acquisition from exercise. Design: The study population included 75 women of 18 - 22 years of age in East Japan and 104 women of 18 - 27 years of age in West Japan. The speed of sound (SOS) of the calcaneus was measured, and the young adult mean (%YAM) was calculated from the SOS. The subjects’ medical history, family history of osteoporosis, and exercise habits were examined using a self-administered questionnaire. Results: There were a significantly greater number of subjects with low %YAM in West Japan. The exercise history and exercise time were significantly higher in West Japan, and the exercise intensity score tended to be higher in East Japan during junior high and high school. A multiple regression analysis by region revealed that the following factors had a significant positive association with the SOS: exercise intensity at elementary school and outdoor sports at junior high school in East Japan;and exercise time at elementary school, muscle mass, and outdoor sports at junior high school in West Japan. On the other hand, exercise time in junior high school in West Japan showed a negative association with the SOS. Conclusions: Regional differences in bone mineral density existed, suggesting a trend toward lower bone mineral density in West Japan. Exercise history and time tended to be higher in West Japan, and exercise intensity scores tended to be higher in East Japan, suggesting that exercise intensity may be more important than exercise time for obtaining bone mineral density.
文摘Objective: To understand the correlation between different degrees of obesity and bone mineral density (BMD). Methods: 772 cases (300 men and 472 females) of Zhuang over 40 years old were randomly selected. The BMD and T score were calculated by measuring the right heel bone using a quantitative-ultrasound densitometer. Body composition index of body weight, waist circumference (WC), waist height ratio (WtHR), body fat percentage (BFP) and visceral fat (VF) were measured using a bioelectrical impedance method. Results: The BMI, WC, and WtHR of the male osteoporosis group were lower than those of the normal bone mass (NBM) group (P Conclusion: BMI is positively correlated with BMD in Zhuang. BFP has a greater correlation with female BMD, and a small reduction in BFP can result in a significant decrease in BMD. BMD of male was positively correlated with abdominal obesity indicators (WC, WtHR, VF). However, abdominal obesity has no obvious effect on the promotion of BMD in women, and increased WtHR can lead to a decrease in BMD. Zhuang can appropriately increase the amount of fat within the normal weight range. At the same time, reasonable exercise and balanced nutrition to avoid excessive obesity or low body weight can reduce the incidence of osteoporosis and osteoporosis fractures.
基金supported by the National Natural Science Foundation of China(Grant no:12272253)Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering(Grant no:2021SX-AT008,2021SX-AT009).
文摘Bone is a complex but orderly mineralized tissue with hydroxyapatite(HA)as the inorganic phase and collagen as the organic phase.Inspired by natural bone tissues,HA-mineralized hydrogels have been widely designed and used in bone tissue engineering.HA is majorly utilized for the treatment of bone defects because of its excellent osteoconduction and bone inductivity.Hydrogel is a three-dimensional hydrophilic network structure with similar properties to the extracellular matrix(ECM).The combination of HA and hydrogels produces a new hybrid material that could effectively promote osteointegration and accelerate the healing of bone defects.In this review,the structure and growth of bone and the common strategies used to prepare HA were briefly introduced.Importantly,we discussed the fabrication of HA mineralized hydrogels from simple blending to in situ mineralization.We hope this review can provide a reference for the development of bone repair hydrogels.
基金supported by the National Natural ScienceFoundation of China (No.81101335)
文摘Persistent generalized low bone mineral density (BMD) has been reported in patients with adolescent idiopathic scoliosis (AIS).However,the exact mechanisms and causes of the low BMD in AIS patients are largely unknown.The purpose of this study was to examine the relationship between the receptor activator of NF-κB ligand (RANKL)/osteoprotegerin (OPG) levels in osteoblasts (OBs) from AIS patients with low BMD and with comparison made between the patients and controls.Twenty AIS patients and eight age-matched controls were included in the present study.The BMD of lumbar spine and proximal femur was measured in all subjects.OBs from the cancellous bone of each subject was harvested and primarily cultured.The mRNA and protein expression of RANKL and OPG in OBs was detected by RT-PCR and Western blotting.The results showed BMD was lower in AIS patients than in controls.A significantly higher mRNA and protein expression of RANKL was observed in OBs from AIS patients,while no significant difference was found in the expression of OPG between AIS patients and controls.As a result,RANKL/OPG ratio in patients with AIS was remarkably higher than controls.Our study preliminarily demonstrated expression of RANKL was higher in OBs from AIS patients with low BMD as compared with controls,suggesting the unbalanced RANKL/OPG ratio caused by an over-expression of RANKL in OBs may be responsible for the low BMD in AIS patients.
基金Supported by A Grant from Sapienza University of Rome,Progetti di Ricerca Universitaria 2010-2011
文摘AIM: To investigate bone mineral density (BMD) in obese children with and without nonalcoholic fatty liver disease (NAFLD); and the association between BMD and serum adipokines, and high-sensitivity C-reactive protein (HSCRP). METHODS: A case-control study was performed. Cases were 44 obese children with NAFLD. The diagnosis of NAFLD was based on magnetic resonance imaging (MRI) with high hepatic fat fraction (≥ 5%). Other causes of chronic liver disease were ruled out. Controls were selected from obese children with normal levels of aminotransferases, and without MRI evidence of fatty liver as well as of other causes of chronic liver diseases. Controls were matched (1-to 1-basis) with thecases on age, gender, pubertal stage and as closely as possible on body mass index-SD score. All participants underwent clinical examination, laboratory tests, and whole body (WB) and lumbar spine (LS) BMD by dual energy X-ray absorptiometry. BMDZ-scores were calcu- lated using race and gender specific LMS curves. RESULTS: Obese children with NAFLD had a significantly lower LS BMDZ-score than those without NAFLD [mean, 0.55 (95%CI: 0.23-0.86) vs 1.29 (95%CI: 0.95-1.63); P < 0.01]. WB BMD Z-score was also decreased in obese children with NAFLD compared to obese children with no NAFLD, though borderline significance was observed [1.55 (95%CI: 1.23-1.87) vs 1.95 (95%CI: 1.67-2.10); P = 0.06]. Children with NAFLD had significantly higher HSCRP, lower adiponectin, but similar leptin levels. Thirty five of the 44 children with MRI-diagnosed NAFLD underwent liver biopsy. Among the children with biopsy-proven NAFLD, 20 (57%) had nonalcoholic steatohepatitis (NASH), while 15 (43%) no NASH. Compared to children without NASH, those with NASH had a significantly lower LS BMD Z-score [mean, 0.27 (95%CI: -0.17-0.71) vs 0.75 (95%CI: 0.13-1.39); P < 0.05] as well as a significantly lower WB BMD Z-score [1.38 (95%CI: 0.89-1.17) vs 1.93 (95%CI: 1.32-2.36); P < 0.05]. In multiple regression analysis, NASH (standardized β coefficient, -0.272; P < 0.01) and HSCRP (standardized β coefficient, -0.192; P < 0.05) were significantly and independently associated with LS BMD Z-score. Similar results were obtained when NAFLD (instead of NASH) was included in the model. WB BMD Z-scores were significantly and independently associated with NASH (standardized β coefficient, -0.248;P < 0.05) and fat mass (standardized β coefficient, -0.224;P < 0.05). CONCLUSION: This study reveals that NAFLD is associated with low BMD in obese children, and that systemic, low-grade inflammation may accelerate loss of bone mass in patients with NAFLD.
文摘BACKGROUND The inflammatory bowel diseases(IBD),Crohn’s disease(CD)and ulcerative colitis(UC)are chronic,immune-mediated disorders of the digestive tract.IBD is considered to be a risk factor for developing osteoporosis;however current literature on this matter is inconsistent.AIM To assess prevalence and development of osteoporosis and low bone mineral density(BMD),and its risk factors,in IBD patients.METHODS Systematic review of population-based studies.Studies were identified by electronic(January 2018)and manual searches(May 2018).Databases searched included EMBASE and PubMed and abstracts from 2014-2018 presented at the United European Gastroenterology Week,the European Crohn’s and Colitis Organisation congress,and Digestive Disease Week were screened.Studies were eligible for inclusion if they investigated either the prevalence of osteoporosis or osteopenia and/or risk factors for osteoporosis or low BMD in IBD patients.Studies on children under the age of 18 were excluded.Only population-based studies were included.All risk factors for osteoporosis and low BMD investigated in any included article were considered.Study quality and the possibility of bias were analysed using the Newcastle-Ottawa scale.RESULTS Twelve studies including 3661 IBD patients and 12789 healthy controls were included.Prevalence of osteoporosis varied between 4%-9%in studies including both CD and UC patients;2%-9% in studies including UC patients, and 7%-15% instudies including CD patients. Among healthy controls, prevalence ofosteoporosis was 3% and 10% in two studies. CD diagnosis, lower body massindex (BMI), and lower body weight were risk factors associated withosteoporosis or low BMD. Findings regarding gender showed inconsistent results.CD patients had an increased risk for osteoporosis or low BMD over time, whileUC patients did not. Increased age was associated with decreased BMD, and therewas a positive association between weight and BMI and BMD over time. Greatheterogeneity was found in the included studies in terms of study methodologies,definitions and the assessment of osteoporosis, and only a small number ofpopulation-based studies was available.CONCLUSIONThis systematic review found a possible increase of prevalence of osteoporosis inCD cohorts when compared to UC and cohorts including both disease types.Lower weight and lower BMI were predictors of osteoporosis or low BMD in IBDpatients. The results varied considerably between studies.
文摘Cone beam computed tomography(CBCT) has often been used to determine the quality of craniofacial bone structures through the determination of mineral density, which is based on gray scales of the images obtained. However, there is no consensus regarding the accuracy of the determination of the gray scales in these exams. This study aims to provide a literature review concerning the reliability of CBCT to determine bone mineral density. The gray values obtained with CBCT show a linear relationship with the attenuation coefficients of the materials, Hounsfield Units values obtained with medical computed tomography, and density values from dual energy X-ray absorciometry. However, errors are expected when CBCT images are used to define the quality of the scanned structures be-cause these images show inconsistencies and arbitrari-ness in the gray values, particularly when related to abrupt change in the density of the object, X-ray beam hardening effect, scattered radiation, projection data discontinuity-related effect, differences between CBCTdevices, changes in the volume of the field of view(FOV), and changes in the relationships of size and position between the FOV and the object evaluated. A few methods of mathematical correction of the gray scales in CBCT have been proposed; however, they do not generate consistent values that are independent of the devices and their configurations or of the scanned objects. Thus, CBCT should not be considered the ex-amination of choice for the determination of bone and soft tissue mineral density at the current stage, par-ticularly when values obtained are to be compared to predetermined standard values. Comparisons between symmetrically positioned structures inside the FOV and in relation to the exomass of the object, as it occurs with the right and left sides of the skull, seem to be viable because the effects on the gray scale in the re-gions of interest are the same.
文摘Determination of dry bulk density and water content measurement of magnetic susceptibility (x) and saturation isothermal remanent magnetization (SIRM), determination of carbonate content, and determination of total organic carbon (TOC) content nitrogen content (N%) and carbon/nitrogen (C/N) ratio are some of the techniques which have been widely applied to lacustrine-sediment analyses. The techniques,complemented by others, are usually useful for revealing characteristics of lacustrine-sediments and thus for postulating hydrological regimes in the lake and environmental conditions and human activity around it in palaeolimnological studies. A very brief review is presented on recent applications of these techniques in palaeolimnological work with English literatures published mainly since 1985 and focus given on interpretations of results of these analyses related to palaeoenvironmental reconstructions. Low dry bulk density and high water content often imply relatively warm and wet conditions. High X and SIRM are usually resulted from reduced dilutions in the lake and intensified erosions on its catchment. both of which can be in turn attributed to environmental changes. While variations in patterns of X and SIRM may give further insight on mineral magnetism and thus implications on environmental conditions. Increased carbonate content seems likely to associate to warm and dry conditions.Increased TOC content is virtually used as one of indicators of warm and wet conditions and variations in C/N ratio may hint variations in relative contributions of different sources, aquatic and terrestrial, to the total organic matter in lake sediments and hence to lake-level fluctuations and climate changes.
文摘Phytic acid is the principal storage form of phosphorus in plant seeds and an essential signalling molecule in several regulatory processes of plant development.However,it is known as an anti-nutrient compound owing to its potent chelating property.Thus,reducing the phytic acid content in crops is desirable.Studies involving regulation of MIPS and IPK1 genes to generate low phytate rice have been reported earlier.However,the functional significance of OsITPK and the effect of its down-regulation on phytic acid content and the associated pleiotropic effects on rice have not yet been investigated.In this study,tissue specific RNA interference(RNAi)-mediated down-regulation of a major ITPK homolog(OsITP5/6K-1)resulted in 46.2%decrease in phytic acid content of T2 transgenic seeds with a subsequent 3-fold enhancement in the inorganic phosphorus content.Silencing of OsITP5/6K-1 altered the transcript levels of essential phytic acid pathway genes,without significantly affecting the transcript levels of other OsITPK homologs.Furthermore,the mapping of elements through X-ray microfluorescence analysis revealed significant changes in the spatial distribution pattern and translocation of elements in low phytate seeds.Additionally,low phytate polished seeds exhibited 1.3-fold and 1.6-fold enhancement in iron and zinc content in the grain endosperm,respectively.Silencing of OsITP5/6K-1 also altered the amino acid and myo-inositol content of the transgenic seeds.Our results successfully established that RNAi-mediated silencing of OsITP5/6K-1 gene significantly reduced the phytate levels in seeds without hampering the germination potential of seeds and plant growth.The present study provided an insight into the mechanism of phytic acid biosynthesis pathway.
文摘BACKGROUND Diabetes is a chronic disease,which may cause various complications.Patients with diabetes are at high risk of bone and joint disorders,such as osteoporosis and bone fractures.In addition,it became widely accepted that diabetes has an important impact on bone metabolism.Metformin is a commonly used and effective first-line treatment for type 2 diabetes.Some glucose-lowering agents have been found to have an effect on bone metabolism.The present study explored if different doses of metformin have an effect on bone mineral density(BMD)and bone metabolism in type 2 diabetes.AIM To investigate the effects of different doses of metformin on BMD and bone metabolism in elderly male patients with type 2 diabetes mellitus.METHODS A total of 120 elderly male outpatients with type 2 diabetes mellitus who were admitted to our hospital were included in the study from July 2018 to June 2019.They were randomly assigned to an experimental group and a control group with 60 patients in each group.Patients in the experimental group were given high dose metformin four times a day 0.5 g each time for 12 wk.Patients in the control group were given low dose metformin orally twice a day 0.5 g each time for 12 wk.The changes in bone mineral density and bone metabolism before and after treatment and the efficacy rate of the treatment were compared between the two groups.RESULTS There was no significant difference in the efficacy rate between the two groups(P>0.05).Before the treatment,there was no significant difference in BMD and bone metabolism between the two groups(P>0.05).However,after the treatment,BMD and bone metabolism were improved in the two groups.Moreover,BMD and 25-hydroxyvitamin D were significantly higher in the experimental group than in the control group,and N-terminal/midregion andβ-isomerized Cterminal telopeptides were significantly lower in the experimental group than in the control group(all P<0.05).There was no significant difference in the incidence of adverse reactions between the two groups(P>0.05).CONCLUSION Both high and low dose metformin can effectively control the blood glucose levels in elderly male patients with type 2 diabetes mellitus.However,the benefits of high dose metformin in improving BMD and bone metabolism level was more obvious in patients with type 2 diabetes mellitus.
文摘The aim of this study was to determine the relationship between obesity and osteoporosis. A total of 30 Saudi women, aged between 20 and 50 years, were selected randomly. We calculated each subject’s body mass index (BMI) and determined their lumbar and femur bone mineral densities using dual-energy X-ray absorptiometry (DXA). We examined the interaction between obesity and bone mineral density (BMD) using logistic regression, after adjusting for age, family history of osteoporosis, maternal fractures, smoking, and any sedentary lifestyles. BMI was shown to be the most effective independent variable with respect to bone density. We evaluated the Pearson correlation coefficients of BMI, BMD of the lumbar spine, and BMD of the femoral neck with reference to the variables of the study, and found a significant correlation (P 30 kg/m2) were at increased risk of osteoporosis at the femoral neck and severe osteopenia in the lumbar spine.
文摘Sorghum is an important staple food crop of Asian and African countries.As a poor man s crop",it provides dietary starch,protein,and some vitamins and minerals.Minerals are important for various physiological functions in the human body.As a major staple crop of central and southern Indian provinces,sorghum landraces are a source of supplementary micronutrients.Concentrations of micronutrients and protein and yield parameters were studied using 112 local landraces and varieties.Univariate analysis revealed wide variation for iron(1.10-9.54 mg 100 g^(-1)),zinc(1.12-7.58 mg 100 g^(-1)),protein(3.50-12.60%),and grain yield(2.50-76.50 g) among the landraces.High estimates of genetic/phenotypic coefficient of variation,and genetic advances over the mean were identified for landraces and varieties.High heritabilities were also identified for yield and mineral content.Correlation estimates among the genotypes indicated that grain yield was positively correlated with copper and protein with copper and zinc.Cluster analysis based on Euclidean distance resolved all of the genotypes into three major clusters.The wide range of values with high heritability estimates may favor the use of these landraces in recombination breeding to improve nutritional quality in sorghum.
基金Supported by Corpus generated by Department of Endocrinology, KEM Hospital, Mumbai, India
文摘AIM:To estimate the prevalence and identify the risk factors for metabolic bone disease in patients with cirrhosis.METHODS:The study was performed on 72 Indian patients with cirrhosis(63 male, 9 female;aged < 50 years).Etiology of cirrhosis was alcoholism(n = 37), hepatitis B(n = 25) and hepatitis C(n = 10).Twenty-three patients belonged to Child class A, while 39 were in class B and 10 in class C.Secondary causes for metabolic bone disease and osteoporosis were ruled out.Sunlight exposure, physical activity and dietary constituents were calculated.Complete metabolic profiles were derived, and bone mineral density(BMD) was measured using dual energy X ray absorptiometry.Low BMD was defined as a Z score below-2.RESULTS:Low BMD was found in 68% of patients.Lumbar spine was the most frequently and severely affected site.Risk factors for low BMD included low physical activity, decreased sunlight exposure, and low lean body mass.Calcium intake was adequate, with unfavorable calcium:protein ratio and calcium:phosphorus ratio.Vitamin D deficiency was highly prevalent(92%).There was a high incidence of hypogonadism(41%).Serum estradiol level was elevated significantly in patients with normal BMD.Insulin-like growth factor(IGF) 1 and IGF binding protein 3 levels were below the age-related normal range in both groups.IGF-1 was signiflcantly lower in patients with low BMD.Serum osteocalcin level was low(68%) and urinary deoxypyridinoline to creatinine ratio was high(79%), which demonstrated low bone formation with high resorption.CONCLUSION:Patients with cirrhosis have low BMD.Contributory factors are reduced physical activity, low lean body mass, vitamin D def iciency and hypogonadism and low IGF-1 level.
文摘After successful kidney transplantation, accumulated waste products and electrolytes are excreted and regulatory hormones return to normal levels. Despite the improvement in mineral metabolites and mineral regulating hormones after kidney transplantation,abnormal bone and mineral metabolism continues to present in most patients. During the first 3 mo, fibroblast growth factor-23(FGF-23) and parathyroid hormone levels decrease rapidly in association with an increase in 1,25-dihydroxyvitamin D production. Renal phosphate excretion resumes and serum calcium, if elevated before, returns toward normal levels. FGF-23 excess during the first 3-12 mo results in exaggerated renal phosphate loss and hypophosphatemia occurs in some patients. After 1 year, FGF-23 and serum phosphate return to normal levels but persistent hyperparathyroidism remains in some patients. The progression of vascular calcification also attenuates. High dose corticosteroid and persistent hyperparathyroidism are the most important factors influencing abnormal bone and mineral metabolism in long-term kidney transplant(KT) recipients. Bone loss occurs at a highest rate during the first 6-12 mo after transplantation. Measurement of bone mineral density is recommended in patients with estimated glomerular filtration rate > 30 mL/min. The use of active vitamin D with or without bisphosphonate is effective in preventing early post-transplant bone loss. Steroid withdrawal regimen is also beneficial in preservation of bone mass in long-term. Calcimimetic is an alternative therapy to parathyroidectomy in KT recipients with persistent hyperparathyroidism. If parathyroidectomy is required, subtotal to near total parathyroidectomy is recommended. Performing parathyroidectomy during the waiting period prior to transplantation is also preferred in patients with severe hyperparathyroidism associated with hypercalcemia.
基金the Agricultural Research Center of Kerman for their financial support
文摘The aim of this study was to compare the quality characteristics and mineral content of the fiber from male and female cashmere goats raised under different management systems. Male and female Raeini cashmere goats (<1.5 years of age, n = 48) were selected from flocks raised at a government breeding station or raised commercially under either rural or nomadic conditions. The staple length, cashmere fiber diameter, coefficient of variation for fiber diameter, percentage of cashmere in a fleece, percentage of guard hair in a fleece and cashmere tenacity averaged 4.6 ±0.1 cm, 18.0 ±0.1 m, 20.9 ± 0.4%, 66.1 ± 1.5%, 33.8 ± 1.5% and 1.8 ± 0.2 gf/tex, respectively. The sulfur, copper and zinc content of the cashmere averaged 2.8 ± 0.1%, 0.00065 ± 0.00002% and 0.01276 ± 0.00025%, respectively. Rearing method significantly affected staple length, coefficient of variation of fiber diameter, cashmere tenacity and copper content. Males had a higher coefficient of variation of fiber diameter and cashmere tenacity than females (P < 0.05).
文摘Bone studies of HIV-infected children using dual X-ray absorptiometry (DXA) suggest bone mineral density (BMD) abnormalities. Pediatric studies are often performed using DXA instead of computed tomography (CT), which accounts for 3-dimensional differences in bone size of growing children. We evaluated whether CT would match DXA measurements in this population. For this purpose, the BMD of 16 perinatally HIV-infected patients, ages 6 to 22 was assessed. Subjects were matched by age, gender, and race to controls. BMD was assessed via DXA and QCT. Clinical anthropometric data, body mass index, immunologic and virologic parameters and laboratory markers for osteoblastic and osteoclastic activity were performed. No statistically significant differences in age and anthropometric parameters between subjects and controls were found. Individual CT and DXA z-scores were significantly different when subjects were evaluated as a group (p = 0.0002) or when males and females were analyzed independently (p = 0.001 and 0.03). DXA z-scores were below 1 SD, while CT z-scores were above the mean. 31% of subjects were identified as having poor bone mineralization by DXA while none had osteopenia/osteoporosis by CT. There was no correlation between immunologic/virologic parameters and BMD by either method. Increased osteoclastic activity was noted in 10 patients receiving tenofovir. In summary, decreased BMD diagnosed by DXA in pediatric HIV-infected subjects was not confirmed by CT. Increased bone turnover in patients on tenofovir was suggested by laboratory markers. Prospective studies using CT as the imaging standard are needed for evaluation of bone mineral changes in HIV-infected children.
