Osteoporosis represents one major health condition for our growing elderly population. It accounts for severe morbidity and increased mortality in postmenopausal women and it is becoming an emerging health concern eve...Osteoporosis represents one major health condition for our growing elderly population. It accounts for severe morbidity and increased mortality in postmenopausal women and it is becoming an emerging health concern even in aging men. Screening of the population at risk for bone degeneration and treatment assessment of osteoporotic patients to prevent bone fragility fractures represent useful tools to improve quality of life in the elderly and to lighten the related socio-economic impact. Bone mineral density(BMD) estimate by means of dual-energy X-ray absorptiometry is normally used in clinical practice for osteoporosis diagnosis. Nevertheless, BMD alone does not represent a good predictor of fracture risk. From a clinical point of view, bone microarchitecture seems to be an intriguing aspect to characterize bone alteration patterns in aging and pathology. The widening into clinical practice of medical imaging techniques and the impressive advances in information technologies together with enhanced capacity of power calculation have promoted proliferation of new methods to assess changes of trabecular bone architecture(TBA) during aging and osteoporosis. Magnetic resonance imaging(MRI) has recently arisen as a useful tool to measure bone structure in vivo. In particular, high-resolution MRI techniques have introduced new perspectives for TBA characterization by non-invasive non-ionizing methods. However, texture analysis methods have not found favor with clinicians as they produce quite a few parameters whose interpretation is difficult. The introduction in biomedical field of paradigms, such as theory of complexity, chaos, and fractals, suggests new approaches and provides innovative tools to develop computerized methods that, by producing a limited number of parameters sensitive to pathology onset and progression, would speed up their application into clinical practice. Complexity of living beings and fractality of several physio-anatomic structures suggest fractal analysis as a promising approach to quantify morphofunctional changes in both aging and pathology. In this particular context, fractal lacunarity seems to be the proper tool to characterize TBA texture as it is able to describe both discontinuity of bone network and sizes of bone marrow spaces, whose changes are an index of bone fracture risk. In this paper, an original method of MRI texture analysis, based on TBA fractal lacunarity is described and discussed in the light of new perspectives for early diagnosis of osteoporotic fractures.展开更多
Hypertension is a primary risk factor for the progression of cognitive impairment caused by cerebral small vessel disease,the most common cerebrovascular disease.Howeve r,the causal relationship between hypertension a...Hypertension is a primary risk factor for the progression of cognitive impairment caused by cerebral small vessel disease,the most common cerebrovascular disease.Howeve r,the causal relationship between hypertension and cerebral small vessel disease remains unclear.Hypertension has substantial negative impacts on brain health and is recognized as a risk factor for cerebrovascular disease.Chronic hypertension and lifestyle factors are associated with risks for stro ke and dementia,and cerebral small vessel disease can cause dementia and stroke.Hypertension is the main driver of cerebral small vessel disease,which changes the structure and function of cerebral vessels via various mechanisms and leads to lacunar infarction,leukoaraiosis,white matter lesions,and intracerebral hemorrhage,ultimately res ulting in cognitive decline and demonstrating that the brain is the to rget organ of hypertension.This review updates our understanding of the pathogenesis of hypertensioninduced cerebral small vessel disease and the res ulting changes in brain structure and function and declines in cognitive ability.We also discuss drugs to treat cerebral small vessel disease and cognitive impairment.展开更多
Lacunarity analysis is frequently used in multiscale and spatial pattern studies.However,the explanation for the lacunarity analysis results is limited mainly at a qualitative description level.In other words,this app...Lacunarity analysis is frequently used in multiscale and spatial pattern studies.However,the explanation for the lacunarity analysis results is limited mainly at a qualitative description level.In other words,this approach can be used to judge whether the spatial pattern of the objective is regular,random or aggregated in space.The lacunarity analysis,however,cannot afford many quantitative information.Therefore,this study proposed the lacunarity variation index(LVI)to reflect the rates of variation of lacunarity with the resolution.In comparison with lacunarity analysis,the simulated experiments show that the LVI analysis can distinguish the basic spatial pattern of the geography objects more clearly and detect the scale of aggregated data.The experiment showed that different slope types in the Loess Plateau display aggregated patterns,and the characteristic scales of these patterns were detected using the slope pattern in the Loess Plateau as the research data.This study can improve the spatial pattern analysis and scale detecting methods,as well as provide a new method for landscape and vegetation community pattern analyses.Lacunarity analysis is frequently used in multiscale and spatial pattern studies.However,the explanation for the lacunarity analysis results is limited mainly at a qualitative description level.In other words,this approach can be used to judge whether the spatial pattern of the objective is regular,random or aggregated in space.The lacunarity analysis,however,cannot afford many quantitative information.Therefore,this study proposed the lacunarity variation index(LVI)to reflect the rates of variation of lacunarity with the resolution.In comparison with lacunarity analysis,the simulated experiments show that the LVI analysis can distinguish the basic spatial pattern of the geography objects more clearly and detect the scale of aggregated data.The experiment showed that different slope types in the Loess Plateau display aggregated patterns,and the characteristic scales of these patterns were detected using the slope pattern in the Loess Plateau as the research data.This study can improve the spatial pattern analysis and scale detecting methods,as well as provide a new method for landscape and vegetation community pattern analyses.展开更多
AIM: To characterize the human retinal vessel arborisation in normal and amblyopic eyes using multifractal geometry and lacunarity parameters.·METHODS: Multifractal analysis using a box counting algorithm was car...AIM: To characterize the human retinal vessel arborisation in normal and amblyopic eyes using multifractal geometry and lacunarity parameters.·METHODS: Multifractal analysis using a box counting algorithm was carried out for a set of 12 segmented and skeletonized human retinal images, corresponding to both normal(6 images) and amblyopia states of the retina(6 images).·RESULTS: It was found that the microvascular geometry of the human retina network represents geometrical multifractals, characterized through subsets of regions having different scaling properties that are not evident in the fractal analysis. Multifractal analysis of the amblyopia images(segmented and skeletonized versions)show a higher average of the generalized dimensions(D q) for q =0, 1, 2 indicating a higher degree of the treedimensional complexity associated with the human retinal microvasculature network whereas images of healthy subjects show a lower value of generalized dimensions indicating normal complexity of biostructure.On the other hand, the lacunarity analysis of the amblyopia images(segmented and skeletonized versions)show a lower average of the lacunarity parameter Λ than the corresponding values for normal images(segmented and skeletonized versions).·CONCLUSION: The multifractal and lacunarity analysis may be used as a non-invasive predictive complementary tool to distinguish amblyopic subjects from healthy subjects and hence this technique could be used for an early diagnosis of patients with amblyopia.展开更多
Background: Benign prostate hyperplasia (BPH) is the most common benign disease of the human prostate. The comparison between global versus local changes in spatial patterns of pathological lesions provoked a growing ...Background: Benign prostate hyperplasia (BPH) is the most common benign disease of the human prostate. The comparison between global versus local changes in spatial patterns of pathological lesions provoked a growing interest in some fields such as neuropathology. To date, there is little data on this subject in prostatic pathology. Given the interest of local parameters to distinguish between normal and pathological structures, the present study will apply first and second order stereological tools to find out if the cytokeratin18 (ck18) immunoexpression shows relevant local changes in BPH compared to normal prostate, independently if global estimates were similar in both groups. Methods: To verify if the global and local changes in immuno-expression of ck18 are relevant to ascertain differences between normal (CTR) and BPH cases, the following parameters will be applied: Volume fraction of epithelium immunostained for ck18 (VV ck18), both in global and local estimates;dispersion indices of VV ck18;estimates of local variance of VV ck18 (positional and of scale) using wavelet analysis;and lacunarity analysis to measure the tissue heterogeneity. Then, the set of values from the parameters studied that show significant differences between CTR and BPH will be employed to perform stepwise linear discriminant analyses to determine if locally estimated parameters were able to classify accurately the cases in CTR and BPH groups. Results and Conclusions: The findings of the present study indicate that changes in the expression of ck18 by the hyperplastic prostatic epithelium are not homogeneous. This limits the use of a single biopsy based markers to predict biological behavior in BPH. On the other hand, the local changes in the expression of ck18 are more evident in terms of VV ck18 and its local variability, whereas other parameters that are useful in other pathologies, such as lacunarity, are less relevant In prostatic hyperplasia.展开更多
Ischemic stroke is a devastating,life altering event which can severely reduce patient quality of life.Despite years of research there have been minimal therapeutic advances.Endothelial progenitor cells(EPCs),stem cel...Ischemic stroke is a devastating,life altering event which can severely reduce patient quality of life.Despite years of research there have been minimal therapeutic advances.Endothelial progenitor cells(EPCs),stem cells involved in both vasculogenesis and angiogenesis,may be a potential therapeutic target.After a stroke,EPCs migrate to the site of ischemic injury to repair cerebrovascular damage,and their numbers and functional capacity may determine patients'outcome.This study aims to determine whether the number of circulating EPCs and their functional aspects may be used as biomarkers to identify the type(cortical or lacunar)and/or severity of ischemic stroke.The study will also investigate if there are any differences in these characteristics between healthy volunteers over and under 65 years of age.100 stroke patients(50 lacunar and 50 cortical strokes)will be recruited in this prospective,observational case-controlled study.Blood samples will be taken from stroke patients at baseline(within 48 hours of stroke)and days 7,30 and90.EPCs will be counted with flow cytometry.The plasma levels of pro-and anti-angiogenic factors and inflammatory cytokines will also be determined.Outgrowth endothelial cells will be cultured to be used in tube formation,migration and proliferation functional assays.Primary outcome is disability or dependence on day 90 after stroke,assessed by the modified Rankin Scale.Secondary outcomes are changes in circulating EPC numbers and/or functional capacity between patient and healthy volunteers,between patient subgroups and between elderly and young healthy volunteers.Recruitment started in February 2017,167 participants have been recruited.Recruitment will end in November 2019.West Midlands-Coventry&Warwickshire Research Ethics Committee approved this study(REC number:16/WM/0304)on September8,2016.Protocol version:2.0.The Bayraktutan Dunhill Medical Trust EPC Study was registered in ClinicalTrials.gov(NCT02980354)on November 15,2016.This study will determine whether the number of EPCs can be used as a prognostic or diagnostic marker for ischemic strokes and is a step towards discovering if transplantation of EPCs may aid patient recovery.展开更多
The association between sleep-disordered breathing(SDB) and cardiovascular risk has been the focus of attention in recent years.Sleep disorders are emerging risk factors for cardiovascular disease and have been relate...The association between sleep-disordered breathing(SDB) and cardiovascular risk has been the focus of attention in recent years.Sleep disorders are emerging risk factors for cardiovascular disease and have been related to the whole spectrum of stroke,including transient ischemic attack,ischemic cerebral infarction and intracerebral haemorrhage.It has been shown that lacunar stroke or lacunar infarctions affecting the internal capsule or the protuberance are associated with a higher frequency of SDB.Acute stroke patients with associated SDB have a worse prognosis and a higher mortality as compared to patients with first-ever stroke without SDB.Preliminary studies provide evidence of the usefulness of treatment with continuous positive airway pressure when SDB is present in stroke patients.展开更多
BACKGROUND The main pathological factor of cerebral infarction is atherosclerosis,which is the pathological process of chronic inflammatory diseases such as vascular smooth muscle hyperplasia,inflammatory cell infiltr...BACKGROUND The main pathological factor of cerebral infarction is atherosclerosis,which is the pathological process of chronic inflammatory diseases such as vascular smooth muscle hyperplasia,inflammatory cell infiltration,extracellular matrix increase,and thrombosis.At present,the focus of clinical treatment is anti-platelet aggregation and improving blood status,and current research is limited to improving symptoms only.AIM To observe the effect of sodium ozagrel and atorvastatin on type 2 diabetes patients with lacunar cerebral infarction.METHODS Eighty-two patients with type 2 diabetes and lacunar cerebral infarction admitted to our hospital from January 2018 to February 2020 were equally categorized into two groups according to their treatment method.The control group was administered atorvastatin,and the observation group was administered sodium ozagrel combined with atorvastatin.The National Institutes of Health stroke scale(NIHSS)score,activities of daily living(ADL)score,blood glucose,lipid levels,inflammatory factors,high-mobility group box 1(HMGB1)levels,paraoxonase-1(PON-1)levels,erythrocyte sedimentation rate(ESR),and macrophage migration inhibitory factor(MIF)levels were recorded before and after treatment.The total effective rate and adverse reaction rate of the two groups were analyzed.RESULTS The total effective rate of the observation group(94.00%)was significantly higher than that of the control group(80.00%)(χ2=3.998;P=0.046).The blood glucose indexes,total cholesterol levels,triglyceride levels,low-density lipoprotein cholesterol levels,high-sensitivity C-reactive protein levels,interleukin-1βlevels,tumor necrosis factor-αlevels,HMGB1 Levels,ESR,MIF levels,platelet aggregation rates,and plasma viscosity of the two groups decreased after treatment;however,high-density lipoprotein cholesterol and PON-1 Levels increased after treatment.After treatment,the blood glucose indexes;blood lipid indexes;inflammatory factors;HMGB1,PON-1,and MIF levels;ESR;platelet aggregation rate;and plasma viscosity of the observation group were better than those of the control group(P<0.05).After treatment,all patients in the observation group had higher ADL scores and lower NIHSS scores than those in the control group(P<0.05).CONCLUSION Sodium ozagrel with atorvastatin can reduce inflammatory reactions;regulate ESR and HMGB1,PON-1,and MIF levels;control blood glucose and lipid indexes;and alleviate nerve injury without increasing adverse effects of atorvastatin alone.展开更多
Objective To study the relationships between cognitive impairment in patients with lacunar infarcts and quantitative CT measures and to determine the independent correlative factors of cognitive impairment.Methods Neu...Objective To study the relationships between cognitive impairment in patients with lacunar infarcts and quantitative CT measures and to determine the independent correlative factors of cognitive impairment.Methods Neuropsychological examination was conducted for 128 patients with acute lacunar infarct.Number,location,and volume of infarcts,cerebral atrophy index and severity of white matter lesions(WMLs) were measured and recorded.Results The number of lacunar infarcts in cognitive impairment (CI) group was significantly larger than that in cognitive normal(CN) group.Mean width of sulcus and sylvian fissure,index of frontal horn and ventricular-brain ratio(VBR) were significantly different in both groups.There were more patients with 3 grades or 4 grades WMLs in CI group(62%) than those in CN group(22%).The total volume of lacunar infarcts showed no statistically significant difference.Logistic regression analysis indicated that the number of lacunar infarcts in frontal subcortex and thalamus,the volume of infarcts in anterior periventricular white matter,width of cerebral sulcus and sylvian fissure were correlated with cognitive impairment respectively.Additionally,age and education were correlative factors of cognitive impairment in patients with lacunar infarct.Conclusion Correlative factors of cognitive impairment in patients with lacunar infarct are not merely one feature,but a combination of infarct features(number,location,and volume),cortical atrophy and host factors(age and education).展开更多
AIM:To investigate the correlation of ischemic ophthalmopathy(IO)with lacunar infarction(LI),an ischemic lesions in the cerebrovascular system.METHODS:Totally 204 cases of IO without any nervous system symptom and pre...AIM:To investigate the correlation of ischemic ophthalmopathy(IO)with lacunar infarction(LI),an ischemic lesions in the cerebrovascular system.METHODS:Totally 204 cases of IO without any nervous system symptom and previously diagnosed LI served as the observational group.All 204 cases without IO,nervous system symptoms and previous LI served as the control group.Age and sex between the two groups matched well.LI was diagnosed by magnetic resonance imaging(MRI)and the results of the two groups were statistically analyzed and compared.RESULTS:IO included 174 eyes of 156 patients with non-arteritis anterior ischemic optic neuropathy(NAION),42 eyes of 36 patients with central retinal artery occlusion(CRAO)or branch retinal artery occlusion(BRAO)and 12 eyes of 12 patients with ocular ischemia syndrome(OIS).The detection rate of LI(72.54%)in IO group was obviously higher than that(15.68%)in the control group(P<0.001).IO was positively correlated with LI(r=0.573,P<0.05).In addition,most infarction sites located in the basal ganglia(67.57%),which were not the vital areas of cerebrum and not easy to be found due to their small size.The majority of those first visited IO patients(72.54%)without nervous system symptom and previously diagnosed LI had already suffered from LI.CONCLUSION:According to our studies,there is a positive correlation between IO and LI.IO can be used as an important predictor for the present of LI,especially obvious signs of the patient.展开更多
Objective We conducted a study using MRI and ambulatory blood pressure monitoring(ABPM) to determine whether an in-apporpriately low nocturnal blood pressure, or an excess fall in nocturnal blood pressure, might be re...Objective We conducted a study using MRI and ambulatory blood pressure monitoring(ABPM) to determine whether an in-apporpriately low nocturnal blood pressure, or an excess fall in nocturnal blood pressure, might be responsible for lacunar infarct. Method ABPM and Casul blood pressure(CBP) were examined in 35 hypertentives with lacunar infarct(LI)and 33 hypertentives without lacunar infarct as control group. Results There is no significant difference of CBP between two groups. But the mean nighttime systolic blood pressure (nSBP) and diastolic blood pressure (nDBP) in patients with lacunar infarct were significantly smaller than in patients without lacunar infarct. The ratio of nSBP/dSBP and nDBP/dDBP in SI were smaller than in control group respectively. Conclusions The results indicate that an inap-propriately low nocturnal blood pressure, or an excessive fall in nocturnal blood pressure, is associated with lacunar infarct. It is necessary not only to control high blood pressure but also to pay attention to circadian changes of blood pressure during the course of anti-hypertensive treatment.展开更多
A 59 year old white male presented with a clinical picture typical of lacunar stroke. However, a thorough diagnostic work up showed that the most probable mechanism of stroke was paradoxical brain embolism through a p...A 59 year old white male presented with a clinical picture typical of lacunar stroke. However, a thorough diagnostic work up showed that the most probable mechanism of stroke was paradoxical brain embolism through a patent foramen ovale. The clinical-neuroradiological mismatch that ultimately lead to the correct interpretation is discussed.展开更多
Pure motor stroke(PMS), also known as pure motor hemiparesis, is the most common of any lacunar form(between one half and two thirds of cases, depending on the series). In an acute stroke registry, 733 patients presen...Pure motor stroke(PMS), also known as pure motor hemiparesis, is the most common of any lacunar form(between one half and two thirds of cases, depending on the series). In an acute stroke registry, 733 patients presented a lacunar infarct and PMS accounted for 12.7%(n = 342) of all first-ever stroke patients and for 48% of all lacunar syndromes. The posterior limb of the internal capsule, corona radiata, and pons are the most frequent brain topographies. Infarcts in the mesencephalus or medullary pyramid have been exceptionally reported. This present update is focused on the clinical evidence and mechanisms underlying the relationship between PMS and different stroke etiologies.展开更多
Objective:To study the correlation between cerebral small vascular disease and constitution types of Traditional Chinese Medicine(TCM).Methods:The severity of lacunar infarction and leukoaraiosis were graded in 230 pa...Objective:To study the correlation between cerebral small vascular disease and constitution types of Traditional Chinese Medicine(TCM).Methods:The severity of lacunar infarction and leukoaraiosis were graded in 230 patients with cerebral small vascular disease,and they were divided into TCM constitution types.The survey of TCM constitution types was carried out by using standardized TCM constitution scale,and order multivariate Logistic regression was used to analyze the correlation between TCM constitution types with severity of lacunar infarction and leukoaraiosis.Results:Yang-deficiency(阳虚)constitution,blood-stasis constitution and phlegm-dampness constitution were the most common TCM constitution types in patients with lacunar infarction,accounting for 33.7%,12.5%,11.5%respectively.Yang-deficiency constitution,blood-stasis constitution and Yin-deficiency(阴虚)constitution were the most common TCM constitution types in patients with leukoaraiosis,accounting for 28.8%,18.5%,13.7%respectively.There were significant differences in lacunar infarction of Yang-deficiency constitution and blood stasis constitution(P<0.05),and there were significant differences in leukoaraiosis of phlegmdampness constitution and blood-stasis constitution(P<0.05).Single factor analysis showed that the main risk factors of lacunar infarction were age,smoking,alcohol consumption,Yang-deficiency constitution and blood-stasis constitution,and the main risk factors of leukoaraiosis were age,smoking,hypertensive disease,phlegm-dampness constitution and blood-stasis constitution.The ordered multivariate Logistic regression analysis found that the severity of lacunar infarction was closely related to age,and the severity of leukoplosis was closely related to age,smoking and hypertension disease.Conclusion:TCM constitution types of lacunar infarction in patients with small cerebral vascular disease is mainly Yang-deficiency constitution and blood-stasis constitution,and the risk factors include age,smoking,alcohol consumption,Yang-deficiency constitution and blood-stasis constitution.Age is closely related with lacunar infarction.TCM constitution types with leukoaraiosis are mainly phlegm-dampness constitution and blood-stasis constitution,and the risk factors are age,smoking,hypertension disease,phlegm-dampness constitution and blood-stasis constitution.Age,smoking and hypertension disease are closely related with leukoaraiosis.展开更多
Injectable hydrogel is suitable for the repair of lacunar bone deficiency.This study fabricated an injectable,self-adaptive silk fibroin/mesoporous bioglass/sodium alginate(SMS)composite hydrogel system.With controlla...Injectable hydrogel is suitable for the repair of lacunar bone deficiency.This study fabricated an injectable,self-adaptive silk fibroin/mesoporous bioglass/sodium alginate(SMS)composite hydrogel system.With controllable and adjustable physical and chemical properties,the SMS hydrogel could be easily optimized adaptively to different clinical applications.The SMS hydrogel effectively showed great injectability and shapeability,allowing defect filling with no gap.Moreover,the SMS hydrogel displayed self-adaptability in mechanical reinforcement and degradation,responsive to the concentration of Ca2+and inflammatory-like pH value in the microenvi-ronment of bone deficiency,respectively.In vitro biological studies indicated that SMS hydrogel could promote osteogenic differentiation of bone marrow mesenchymal stem cells by activation of the MAPK signaling pathway.The SMS hydrogel also could improve migration and tube formation of human umbilical vein endothelial cells.Investigations of the crosstalk between osteoblasts and macrophages confirmed that SMS hydrogel could regulate macrophage polarization from M1 to M2,which could create a specific favorable environment to induce new bone formation and angiogenesis.Meanwhile,SMS hydrogel was proved to be antibacterial,especially for gram-negative bacteria.Furthermore,in vivo study indicated that SMS could be easily applied for maxillary sinus elevation,inducing sufficient new bone formation.Thus,it is convincing that SMS hydrogel could be potent in a simple,minimally invasive and efficient treatment for the repair of lacunar bone deficiency.展开更多
The manuscript attempts to explore the periodicity in the distribution of galaxies in the recently reported Saraswati supercluster and the Stripe 82 region containing it as an example.The report of 120 Mpc periodicity...The manuscript attempts to explore the periodicity in the distribution of galaxies in the recently reported Saraswati supercluster and the Stripe 82 region containing it as an example.The report of 120 Mpc periodicity in the Abell galaxy clusters by power spectrum analysis is the motivation behind the study.The power spectral analysis across the central part of the Stripe 82 region shows a periodic variation of 3.09°or 71 Mpc in fractal dimension whereas an average angular periodicity of 3.45°or 94 Mpc is observed across the Stripe 82 region.This refers to the periodicity of complexity or cluster density of galaxy distribution.The texture of the distribution pattern understood through lacunarity analysis indicates a near symmetric distribution.Fractal dimensions like box-counting dimension,information dimension and correlation dimension are also found through multifractal analysis.While the information dimension tells about the distribution density of galactic points,the correlation dimension details the distribution of galaxies in the neighbourhood.展开更多
Researchers emphasized acute lacunar stroke(ALS)patients suffer from poor social/physical outcomes,cognitive decline,and decreased quality of life.We hypothesized brain abnormalities may occur in ALS during this parti...Researchers emphasized acute lacunar stroke(ALS)patients suffer from poor social/physical outcomes,cognitive decline,and decreased quality of life.We hypothesized brain abnormalities may occur in ALS during this particular stage and may be associated with cognitive deficits upon evaluation.We investigated structural abnormalities in ALS using magnetic resonance imaging and voxel-based morphometry conducted on 28 healthy controls(HC)and 29 patients with ALS and proximal anterior circulation occlusion within 12 hours of symptom onset.Mini-Mental State Examination(MMSE)scores were used to evaluate cognitive dysfunction.Decreased gray matter(GM)in ALS vs.HC was predominantly in the superior frontal gyrus,inferior frontal gyrus,insula,superior temporal gyrus(STG),heschl gyrus,middle temporal gyrus(MTG),posterior cingulate cortex(PCC),hippocampus(HIP),and others.Positive correlation was found between GM density and MMSE scores in STG(r=0.59,p=0.0007),MTG(r=0.46,p=0.01),PCC(r=0.42,p=0.02),HIP(r=0.4,p=0.03),and medial prefrontal cortex(r=0.5,p=0.005).This study provided further information on pathophysiological/morphological mechanisms related to cognitive impairment in ALS and is the basis for further studies in aging-related diseases.展开更多
文摘Osteoporosis represents one major health condition for our growing elderly population. It accounts for severe morbidity and increased mortality in postmenopausal women and it is becoming an emerging health concern even in aging men. Screening of the population at risk for bone degeneration and treatment assessment of osteoporotic patients to prevent bone fragility fractures represent useful tools to improve quality of life in the elderly and to lighten the related socio-economic impact. Bone mineral density(BMD) estimate by means of dual-energy X-ray absorptiometry is normally used in clinical practice for osteoporosis diagnosis. Nevertheless, BMD alone does not represent a good predictor of fracture risk. From a clinical point of view, bone microarchitecture seems to be an intriguing aspect to characterize bone alteration patterns in aging and pathology. The widening into clinical practice of medical imaging techniques and the impressive advances in information technologies together with enhanced capacity of power calculation have promoted proliferation of new methods to assess changes of trabecular bone architecture(TBA) during aging and osteoporosis. Magnetic resonance imaging(MRI) has recently arisen as a useful tool to measure bone structure in vivo. In particular, high-resolution MRI techniques have introduced new perspectives for TBA characterization by non-invasive non-ionizing methods. However, texture analysis methods have not found favor with clinicians as they produce quite a few parameters whose interpretation is difficult. The introduction in biomedical field of paradigms, such as theory of complexity, chaos, and fractals, suggests new approaches and provides innovative tools to develop computerized methods that, by producing a limited number of parameters sensitive to pathology onset and progression, would speed up their application into clinical practice. Complexity of living beings and fractality of several physio-anatomic structures suggest fractal analysis as a promising approach to quantify morphofunctional changes in both aging and pathology. In this particular context, fractal lacunarity seems to be the proper tool to characterize TBA texture as it is able to describe both discontinuity of bone network and sizes of bone marrow spaces, whose changes are an index of bone fracture risk. In this paper, an original method of MRI texture analysis, based on TBA fractal lacunarity is described and discussed in the light of new perspectives for early diagnosis of osteoporotic fractures.
基金supported by the National Natural Science Foundation of China,Nos.82274611 (to LZ),82104419 (to DM)Capital Science and Technology Leading Talent Training Project,No.Z1 91100006119017 (to LZ)+3 种基金Beijing Hospitals Authority Ascent Plan,No.DFL20190803 (to LZ)Cultivation Fund of Hospital Management Center in Beijing,No.PZ2022006 (to DM)R&D Program of Beijing Municipal Education Commission,No.KM202210025017 (to DM)Beijing Gold-Bridge Project,No.ZZ20145 (to DM)。
文摘Hypertension is a primary risk factor for the progression of cognitive impairment caused by cerebral small vessel disease,the most common cerebrovascular disease.Howeve r,the causal relationship between hypertension and cerebral small vessel disease remains unclear.Hypertension has substantial negative impacts on brain health and is recognized as a risk factor for cerebrovascular disease.Chronic hypertension and lifestyle factors are associated with risks for stro ke and dementia,and cerebral small vessel disease can cause dementia and stroke.Hypertension is the main driver of cerebral small vessel disease,which changes the structure and function of cerebral vessels via various mechanisms and leads to lacunar infarction,leukoaraiosis,white matter lesions,and intracerebral hemorrhage,ultimately res ulting in cognitive decline and demonstrating that the brain is the to rget organ of hypertension.This review updates our understanding of the pathogenesis of hypertensioninduced cerebral small vessel disease and the res ulting changes in brain structure and function and declines in cognitive ability.We also discuss drugs to treat cerebral small vessel disease and cognitive impairment.
基金supported by the National Natural Science Foundation of China(Grant Nos.41930102,41571383,41771415,41801321,and 41701450).
文摘Lacunarity analysis is frequently used in multiscale and spatial pattern studies.However,the explanation for the lacunarity analysis results is limited mainly at a qualitative description level.In other words,this approach can be used to judge whether the spatial pattern of the objective is regular,random or aggregated in space.The lacunarity analysis,however,cannot afford many quantitative information.Therefore,this study proposed the lacunarity variation index(LVI)to reflect the rates of variation of lacunarity with the resolution.In comparison with lacunarity analysis,the simulated experiments show that the LVI analysis can distinguish the basic spatial pattern of the geography objects more clearly and detect the scale of aggregated data.The experiment showed that different slope types in the Loess Plateau display aggregated patterns,and the characteristic scales of these patterns were detected using the slope pattern in the Loess Plateau as the research data.This study can improve the spatial pattern analysis and scale detecting methods,as well as provide a new method for landscape and vegetation community pattern analyses.Lacunarity analysis is frequently used in multiscale and spatial pattern studies.However,the explanation for the lacunarity analysis results is limited mainly at a qualitative description level.In other words,this approach can be used to judge whether the spatial pattern of the objective is regular,random or aggregated in space.The lacunarity analysis,however,cannot afford many quantitative information.Therefore,this study proposed the lacunarity variation index(LVI)to reflect the rates of variation of lacunarity with the resolution.In comparison with lacunarity analysis,the simulated experiments show that the LVI analysis can distinguish the basic spatial pattern of the geography objects more clearly and detect the scale of aggregated data.The experiment showed that different slope types in the Loess Plateau display aggregated patterns,and the characteristic scales of these patterns were detected using the slope pattern in the Loess Plateau as the research data.This study can improve the spatial pattern analysis and scale detecting methods,as well as provide a new method for landscape and vegetation community pattern analyses.
文摘AIM: To characterize the human retinal vessel arborisation in normal and amblyopic eyes using multifractal geometry and lacunarity parameters.·METHODS: Multifractal analysis using a box counting algorithm was carried out for a set of 12 segmented and skeletonized human retinal images, corresponding to both normal(6 images) and amblyopia states of the retina(6 images).·RESULTS: It was found that the microvascular geometry of the human retina network represents geometrical multifractals, characterized through subsets of regions having different scaling properties that are not evident in the fractal analysis. Multifractal analysis of the amblyopia images(segmented and skeletonized versions)show a higher average of the generalized dimensions(D q) for q =0, 1, 2 indicating a higher degree of the treedimensional complexity associated with the human retinal microvasculature network whereas images of healthy subjects show a lower value of generalized dimensions indicating normal complexity of biostructure.On the other hand, the lacunarity analysis of the amblyopia images(segmented and skeletonized versions)show a lower average of the lacunarity parameter Λ than the corresponding values for normal images(segmented and skeletonized versions).·CONCLUSION: The multifractal and lacunarity analysis may be used as a non-invasive predictive complementary tool to distinguish amblyopic subjects from healthy subjects and hence this technique could be used for an early diagnosis of patients with amblyopia.
文摘Background: Benign prostate hyperplasia (BPH) is the most common benign disease of the human prostate. The comparison between global versus local changes in spatial patterns of pathological lesions provoked a growing interest in some fields such as neuropathology. To date, there is little data on this subject in prostatic pathology. Given the interest of local parameters to distinguish between normal and pathological structures, the present study will apply first and second order stereological tools to find out if the cytokeratin18 (ck18) immunoexpression shows relevant local changes in BPH compared to normal prostate, independently if global estimates were similar in both groups. Methods: To verify if the global and local changes in immuno-expression of ck18 are relevant to ascertain differences between normal (CTR) and BPH cases, the following parameters will be applied: Volume fraction of epithelium immunostained for ck18 (VV ck18), both in global and local estimates;dispersion indices of VV ck18;estimates of local variance of VV ck18 (positional and of scale) using wavelet analysis;and lacunarity analysis to measure the tissue heterogeneity. Then, the set of values from the parameters studied that show significant differences between CTR and BPH will be employed to perform stepwise linear discriminant analyses to determine if locally estimated parameters were able to classify accurately the cases in CTR and BPH groups. Results and Conclusions: The findings of the present study indicate that changes in the expression of ck18 by the hyperplastic prostatic epithelium are not homogeneous. This limits the use of a single biopsy based markers to predict biological behavior in BPH. On the other hand, the local changes in the expression of ck18 are more evident in terms of VV ck18 and its local variability, whereas other parameters that are useful in other pathologies, such as lacunarity, are less relevant In prostatic hyperplasia.
基金supported by a grant to Dr Ulvi Bayraktutan from The Dunhill Medical Trust(R459/0216)
文摘Ischemic stroke is a devastating,life altering event which can severely reduce patient quality of life.Despite years of research there have been minimal therapeutic advances.Endothelial progenitor cells(EPCs),stem cells involved in both vasculogenesis and angiogenesis,may be a potential therapeutic target.After a stroke,EPCs migrate to the site of ischemic injury to repair cerebrovascular damage,and their numbers and functional capacity may determine patients'outcome.This study aims to determine whether the number of circulating EPCs and their functional aspects may be used as biomarkers to identify the type(cortical or lacunar)and/or severity of ischemic stroke.The study will also investigate if there are any differences in these characteristics between healthy volunteers over and under 65 years of age.100 stroke patients(50 lacunar and 50 cortical strokes)will be recruited in this prospective,observational case-controlled study.Blood samples will be taken from stroke patients at baseline(within 48 hours of stroke)and days 7,30 and90.EPCs will be counted with flow cytometry.The plasma levels of pro-and anti-angiogenic factors and inflammatory cytokines will also be determined.Outgrowth endothelial cells will be cultured to be used in tube formation,migration and proliferation functional assays.Primary outcome is disability or dependence on day 90 after stroke,assessed by the modified Rankin Scale.Secondary outcomes are changes in circulating EPC numbers and/or functional capacity between patient and healthy volunteers,between patient subgroups and between elderly and young healthy volunteers.Recruitment started in February 2017,167 participants have been recruited.Recruitment will end in November 2019.West Midlands-Coventry&Warwickshire Research Ethics Committee approved this study(REC number:16/WM/0304)on September8,2016.Protocol version:2.0.The Bayraktutan Dunhill Medical Trust EPC Study was registered in ClinicalTrials.gov(NCT02980354)on November 15,2016.This study will determine whether the number of EPCs can be used as a prognostic or diagnostic marker for ischemic strokes and is a step towards discovering if transplantation of EPCs may aid patient recovery.
文摘The association between sleep-disordered breathing(SDB) and cardiovascular risk has been the focus of attention in recent years.Sleep disorders are emerging risk factors for cardiovascular disease and have been related to the whole spectrum of stroke,including transient ischemic attack,ischemic cerebral infarction and intracerebral haemorrhage.It has been shown that lacunar stroke or lacunar infarctions affecting the internal capsule or the protuberance are associated with a higher frequency of SDB.Acute stroke patients with associated SDB have a worse prognosis and a higher mortality as compared to patients with first-ever stroke without SDB.Preliminary studies provide evidence of the usefulness of treatment with continuous positive airway pressure when SDB is present in stroke patients.
文摘BACKGROUND The main pathological factor of cerebral infarction is atherosclerosis,which is the pathological process of chronic inflammatory diseases such as vascular smooth muscle hyperplasia,inflammatory cell infiltration,extracellular matrix increase,and thrombosis.At present,the focus of clinical treatment is anti-platelet aggregation and improving blood status,and current research is limited to improving symptoms only.AIM To observe the effect of sodium ozagrel and atorvastatin on type 2 diabetes patients with lacunar cerebral infarction.METHODS Eighty-two patients with type 2 diabetes and lacunar cerebral infarction admitted to our hospital from January 2018 to February 2020 were equally categorized into two groups according to their treatment method.The control group was administered atorvastatin,and the observation group was administered sodium ozagrel combined with atorvastatin.The National Institutes of Health stroke scale(NIHSS)score,activities of daily living(ADL)score,blood glucose,lipid levels,inflammatory factors,high-mobility group box 1(HMGB1)levels,paraoxonase-1(PON-1)levels,erythrocyte sedimentation rate(ESR),and macrophage migration inhibitory factor(MIF)levels were recorded before and after treatment.The total effective rate and adverse reaction rate of the two groups were analyzed.RESULTS The total effective rate of the observation group(94.00%)was significantly higher than that of the control group(80.00%)(χ2=3.998;P=0.046).The blood glucose indexes,total cholesterol levels,triglyceride levels,low-density lipoprotein cholesterol levels,high-sensitivity C-reactive protein levels,interleukin-1βlevels,tumor necrosis factor-αlevels,HMGB1 Levels,ESR,MIF levels,platelet aggregation rates,and plasma viscosity of the two groups decreased after treatment;however,high-density lipoprotein cholesterol and PON-1 Levels increased after treatment.After treatment,the blood glucose indexes;blood lipid indexes;inflammatory factors;HMGB1,PON-1,and MIF levels;ESR;platelet aggregation rate;and plasma viscosity of the observation group were better than those of the control group(P<0.05).After treatment,all patients in the observation group had higher ADL scores and lower NIHSS scores than those in the control group(P<0.05).CONCLUSION Sodium ozagrel with atorvastatin can reduce inflammatory reactions;regulate ESR and HMGB1,PON-1,and MIF levels;control blood glucose and lipid indexes;and alleviate nerve injury without increasing adverse effects of atorvastatin alone.
基金This study was supported by Shaanxi Science Technology Study Development Plan Item(No.2006K13-G7-6)Xi'an Science Technology Study Development Plan Item(No.GG05140).
文摘Objective To study the relationships between cognitive impairment in patients with lacunar infarcts and quantitative CT measures and to determine the independent correlative factors of cognitive impairment.Methods Neuropsychological examination was conducted for 128 patients with acute lacunar infarct.Number,location,and volume of infarcts,cerebral atrophy index and severity of white matter lesions(WMLs) were measured and recorded.Results The number of lacunar infarcts in cognitive impairment (CI) group was significantly larger than that in cognitive normal(CN) group.Mean width of sulcus and sylvian fissure,index of frontal horn and ventricular-brain ratio(VBR) were significantly different in both groups.There were more patients with 3 grades or 4 grades WMLs in CI group(62%) than those in CN group(22%).The total volume of lacunar infarcts showed no statistically significant difference.Logistic regression analysis indicated that the number of lacunar infarcts in frontal subcortex and thalamus,the volume of infarcts in anterior periventricular white matter,width of cerebral sulcus and sylvian fissure were correlated with cognitive impairment respectively.Additionally,age and education were correlative factors of cognitive impairment in patients with lacunar infarct.Conclusion Correlative factors of cognitive impairment in patients with lacunar infarct are not merely one feature,but a combination of infarct features(number,location,and volume),cortical atrophy and host factors(age and education).
基金Supported by National Natural Science Foundation of China(No.81500726)Health Research Program of Shaanxi,China(No.2014E12)Shaanxi Health Research Foundation(No.2016E007)。
文摘AIM:To investigate the correlation of ischemic ophthalmopathy(IO)with lacunar infarction(LI),an ischemic lesions in the cerebrovascular system.METHODS:Totally 204 cases of IO without any nervous system symptom and previously diagnosed LI served as the observational group.All 204 cases without IO,nervous system symptoms and previous LI served as the control group.Age and sex between the two groups matched well.LI was diagnosed by magnetic resonance imaging(MRI)and the results of the two groups were statistically analyzed and compared.RESULTS:IO included 174 eyes of 156 patients with non-arteritis anterior ischemic optic neuropathy(NAION),42 eyes of 36 patients with central retinal artery occlusion(CRAO)or branch retinal artery occlusion(BRAO)and 12 eyes of 12 patients with ocular ischemia syndrome(OIS).The detection rate of LI(72.54%)in IO group was obviously higher than that(15.68%)in the control group(P<0.001).IO was positively correlated with LI(r=0.573,P<0.05).In addition,most infarction sites located in the basal ganglia(67.57%),which were not the vital areas of cerebrum and not easy to be found due to their small size.The majority of those first visited IO patients(72.54%)without nervous system symptom and previously diagnosed LI had already suffered from LI.CONCLUSION:According to our studies,there is a positive correlation between IO and LI.IO can be used as an important predictor for the present of LI,especially obvious signs of the patient.
文摘Objective We conducted a study using MRI and ambulatory blood pressure monitoring(ABPM) to determine whether an in-apporpriately low nocturnal blood pressure, or an excess fall in nocturnal blood pressure, might be responsible for lacunar infarct. Method ABPM and Casul blood pressure(CBP) were examined in 35 hypertentives with lacunar infarct(LI)and 33 hypertentives without lacunar infarct as control group. Results There is no significant difference of CBP between two groups. But the mean nighttime systolic blood pressure (nSBP) and diastolic blood pressure (nDBP) in patients with lacunar infarct were significantly smaller than in patients without lacunar infarct. The ratio of nSBP/dSBP and nDBP/dDBP in SI were smaller than in control group respectively. Conclusions The results indicate that an inap-propriately low nocturnal blood pressure, or an excessive fall in nocturnal blood pressure, is associated with lacunar infarct. It is necessary not only to control high blood pressure but also to pay attention to circadian changes of blood pressure during the course of anti-hypertensive treatment.
文摘A 59 year old white male presented with a clinical picture typical of lacunar stroke. However, a thorough diagnostic work up showed that the most probable mechanism of stroke was paradoxical brain embolism through a patent foramen ovale. The clinical-neuroradiological mismatch that ultimately lead to the correct interpretation is discussed.
文摘Pure motor stroke(PMS), also known as pure motor hemiparesis, is the most common of any lacunar form(between one half and two thirds of cases, depending on the series). In an acute stroke registry, 733 patients presented a lacunar infarct and PMS accounted for 12.7%(n = 342) of all first-ever stroke patients and for 48% of all lacunar syndromes. The posterior limb of the internal capsule, corona radiata, and pons are the most frequent brain topographies. Infarcts in the mesencephalus or medullary pyramid have been exceptionally reported. This present update is focused on the clinical evidence and mechanisms underlying the relationship between PMS and different stroke etiologies.
文摘Objective:To study the correlation between cerebral small vascular disease and constitution types of Traditional Chinese Medicine(TCM).Methods:The severity of lacunar infarction and leukoaraiosis were graded in 230 patients with cerebral small vascular disease,and they were divided into TCM constitution types.The survey of TCM constitution types was carried out by using standardized TCM constitution scale,and order multivariate Logistic regression was used to analyze the correlation between TCM constitution types with severity of lacunar infarction and leukoaraiosis.Results:Yang-deficiency(阳虚)constitution,blood-stasis constitution and phlegm-dampness constitution were the most common TCM constitution types in patients with lacunar infarction,accounting for 33.7%,12.5%,11.5%respectively.Yang-deficiency constitution,blood-stasis constitution and Yin-deficiency(阴虚)constitution were the most common TCM constitution types in patients with leukoaraiosis,accounting for 28.8%,18.5%,13.7%respectively.There were significant differences in lacunar infarction of Yang-deficiency constitution and blood stasis constitution(P<0.05),and there were significant differences in leukoaraiosis of phlegmdampness constitution and blood-stasis constitution(P<0.05).Single factor analysis showed that the main risk factors of lacunar infarction were age,smoking,alcohol consumption,Yang-deficiency constitution and blood-stasis constitution,and the main risk factors of leukoaraiosis were age,smoking,hypertensive disease,phlegm-dampness constitution and blood-stasis constitution.The ordered multivariate Logistic regression analysis found that the severity of lacunar infarction was closely related to age,and the severity of leukoplosis was closely related to age,smoking and hypertension disease.Conclusion:TCM constitution types of lacunar infarction in patients with small cerebral vascular disease is mainly Yang-deficiency constitution and blood-stasis constitution,and the risk factors include age,smoking,alcohol consumption,Yang-deficiency constitution and blood-stasis constitution.Age is closely related with lacunar infarction.TCM constitution types with leukoaraiosis are mainly phlegm-dampness constitution and blood-stasis constitution,and the risk factors are age,smoking,hypertension disease,phlegm-dampness constitution and blood-stasis constitution.Age,smoking and hypertension disease are closely related with leukoaraiosis.
基金National Natural Science Foundation of China(Nos.82130027,82100963,82270953,81991505 and 81921002)Shanghai Rising-Star Program(21QA1405400)+1 种基金Natural Science Foundation of Shanghai(22ZR1436400)Innovative Research Team of High-Level Local Universities in Shanghai.
文摘Injectable hydrogel is suitable for the repair of lacunar bone deficiency.This study fabricated an injectable,self-adaptive silk fibroin/mesoporous bioglass/sodium alginate(SMS)composite hydrogel system.With controllable and adjustable physical and chemical properties,the SMS hydrogel could be easily optimized adaptively to different clinical applications.The SMS hydrogel effectively showed great injectability and shapeability,allowing defect filling with no gap.Moreover,the SMS hydrogel displayed self-adaptability in mechanical reinforcement and degradation,responsive to the concentration of Ca2+and inflammatory-like pH value in the microenvi-ronment of bone deficiency,respectively.In vitro biological studies indicated that SMS hydrogel could promote osteogenic differentiation of bone marrow mesenchymal stem cells by activation of the MAPK signaling pathway.The SMS hydrogel also could improve migration and tube formation of human umbilical vein endothelial cells.Investigations of the crosstalk between osteoblasts and macrophages confirmed that SMS hydrogel could regulate macrophage polarization from M1 to M2,which could create a specific favorable environment to induce new bone formation and angiogenesis.Meanwhile,SMS hydrogel was proved to be antibacterial,especially for gram-negative bacteria.Furthermore,in vivo study indicated that SMS could be easily applied for maxillary sinus elevation,inducing sufficient new bone formation.Thus,it is convincing that SMS hydrogel could be potent in a simple,minimally invasive and efficient treatment for the repair of lacunar bone deficiency.
文摘The manuscript attempts to explore the periodicity in the distribution of galaxies in the recently reported Saraswati supercluster and the Stripe 82 region containing it as an example.The report of 120 Mpc periodicity in the Abell galaxy clusters by power spectrum analysis is the motivation behind the study.The power spectral analysis across the central part of the Stripe 82 region shows a periodic variation of 3.09°or 71 Mpc in fractal dimension whereas an average angular periodicity of 3.45°or 94 Mpc is observed across the Stripe 82 region.This refers to the periodicity of complexity or cluster density of galaxy distribution.The texture of the distribution pattern understood through lacunarity analysis indicates a near symmetric distribution.Fractal dimensions like box-counting dimension,information dimension and correlation dimension are also found through multifractal analysis.While the information dimension tells about the distribution density of galactic points,the correlation dimension details the distribution of galaxies in the neighbourhood.
文摘Researchers emphasized acute lacunar stroke(ALS)patients suffer from poor social/physical outcomes,cognitive decline,and decreased quality of life.We hypothesized brain abnormalities may occur in ALS during this particular stage and may be associated with cognitive deficits upon evaluation.We investigated structural abnormalities in ALS using magnetic resonance imaging and voxel-based morphometry conducted on 28 healthy controls(HC)and 29 patients with ALS and proximal anterior circulation occlusion within 12 hours of symptom onset.Mini-Mental State Examination(MMSE)scores were used to evaluate cognitive dysfunction.Decreased gray matter(GM)in ALS vs.HC was predominantly in the superior frontal gyrus,inferior frontal gyrus,insula,superior temporal gyrus(STG),heschl gyrus,middle temporal gyrus(MTG),posterior cingulate cortex(PCC),hippocampus(HIP),and others.Positive correlation was found between GM density and MMSE scores in STG(r=0.59,p=0.0007),MTG(r=0.46,p=0.01),PCC(r=0.42,p=0.02),HIP(r=0.4,p=0.03),and medial prefrontal cortex(r=0.5,p=0.005).This study provided further information on pathophysiological/morphological mechanisms related to cognitive impairment in ALS and is the basis for further studies in aging-related diseases.
