BACKGROUD: Venous thromboembolism (VTE) including DVT and pulmonary embolism (PE) can be a devastating complication in postoperative patients which is also considered the most likely to be prevented. The proper assess...BACKGROUD: Venous thromboembolism (VTE) including DVT and pulmonary embolism (PE) can be a devastating complication in postoperative patients which is also considered the most likely to be prevented. The proper assessment and effective identification of high risk factors of DVT are the basis for its prevention. We used the Caprini risk assessment model (Caprini RAM) based on many researches about the validation of DVT risk assessment model, and combined the recommendations reported in American College of Chest Physicians Evidence-Based Clinical Practice Guidelines (9th) and Chinese Orthopaedics Association guideline, to give surgical patients stratified prophylaxis. STUDY DESIGN: Between April 2016 and December 2016, we conducted a controlled trial study in 4 surgical departments including Gynecology Department, Joint Surgery, Spinal Surgery and Urology Surgery. 764 patients were included in control group, and 772 patients were included in intervention group. We used the original assessment and prevention methods in control group, while applied the stratified prophylaxis based on Caprini risk assessment level in intervention group. The incidence of DVT was analyzed using chi-square test, while patients’ hospital day was analyzed by independent t-tests. RESULTS: There was significantly difference in incidence rate of DVT between the two groups (13.09‰ vs. 2.59‰, P < 0.05), while the difference in hospital day was not significantly (10.63 ± 5.80 vs. 10.29 ± 5.18, P > 0.05). Most of the surgical patients were with moderate or high-risk (64.93%). CONCLUSIONS: Nurses could identify DVT risk factors in surgical patients using the Caprini risk assessment scale, and apply targeted stratified prophylaxis according to risk level. This model makes DVT risk assessment and intervention process more standardized and effective. It can also reduce incidence rate of DVT significantly. .展开更多
This paper addresses the extremal problem of the null subcarriers based Doppler scale estimation in underwater acoustic(UWA) orthogonal frequency division multiplexing(OFDM) communication. The cost function constructe...This paper addresses the extremal problem of the null subcarriers based Doppler scale estimation in underwater acoustic(UWA) orthogonal frequency division multiplexing(OFDM) communication. The cost function constructed of the total energy of null subcarriers through discrete Fourier transform(DFT) is proposed.The frequencies of null subcarriers are identified from non-uniform Doppler shift at each tentative scaling factor. Then it is proved that the cost function can be fitted as a quadratic polynomial near the global minimum. An accurate Doppler scale estimation is achieved by the location of the global scarifying precision and increasing the computation minimum through polynomial interpolation,without complexity. A shallow water experiment is conducted to demonstrate the performance of the proposed method. Excellent performance results are obtained in ultrawideband UWA channels with a relative bandwidth of 67%, when the transmitter and the receiver are moving at a relative speed of 5 kn, which validates the proposed method.展开更多
The formulation of hard chromium plating from trivalent chromium electrolyte and its related process have been intensively studied in this work. Through optimized conditions, the coating hardness can achieve more than...The formulation of hard chromium plating from trivalent chromium electrolyte and its related process have been intensively studied in this work. Through optimized conditions, the coating hardness can achieve more than HV0.1900 without any treatment and HV0.11700 after heat treatment for five minutes at 300°C, and the thickness of hard chromium coating was about 100 μm. The hard chromium coatings show good adhesion on the carbon steel and low alloy structural steel. The corrosion resistance of hard chromium coatings was enhanced by the adding nanometer materials into trivalent chromium plating coatings. More than 120 hours salt spray corrosion resistance can be achieved with 40 to 50 microns thickness of trivalent chromium plating coatings.展开更多
Aim To determine cephalometrically the mechanism of the treatment effects of non-extraction and multiloop edgewise archwire (MEAW) technique on postpeak ClassⅡ Division 1 patients. Methodology In this retrospective s...Aim To determine cephalometrically the mechanism of the treatment effects of non-extraction and multiloop edgewise archwire (MEAW) technique on postpeak ClassⅡ Division 1 patients. Methodology In this retrospective study, 16 postpeak ClassⅡ Division 1 patients successfully corrected using a non-extraction and MEAW technique were cephalometrically evaluated and compared with 16 matched control subjects treated using an extraction technique. Using CorelDRAW? software, standardized digital cephalograms pre-and post-active treatments were traced and a reference grid was set up. The superimpositions were based on the cranial base, the mandibular and the maxilla regions,and skeletal and dental changes were measured. Changes following treatment were evaluated using the paired-sample t-test. Student's t-test for unpaired samples was used to assess the differences in changes between the MEAW and the extraction control groups. Results The correction of the molar relationships comprised 54% skeletal change (mainly the advancement of the mandible) and 46% dental change. Correction of the anterior teeth relationships comprised 30% skeletal change and 70% dental change. Conclusion The MEAW technique can produce the desired vertical and sagittal movement of the tooth segment and then effectively stimulate mandibular advancement by utilizing the residual growth potential of the condyle.展开更多
BACKGROUND:Limbic encephalitis is a rare syndrome that specifically affects the limbic system. Magnetic resonance imaging(MRI) has been typically used to detect brain changes in this disease. However,the mechanisms of...BACKGROUND:Limbic encephalitis is a rare syndrome that specifically affects the limbic system. Magnetic resonance imaging(MRI) has been typically used to detect brain changes in this disease. However,the mechanisms of limbic encephalitis-related white matter damage remain poorly understood. OBJECTIVE:To characterize white matter connectivity changes secondary to injuries of the limbic system in limbic encephalitis through combined application of diffusion tensor imaging(DTI) and voxel-based morphometry. DESIGN,TIME AND SETTING:A non-randomized,controlled,clinical,neuroimaging,DTI study was performed at the Department of Radiology,West China Hospital in December 2008. PARTICIPANTS:A male,46-year-old,limbic encephalitis patient,as well as 11 age- and gender-matched healthy volunteers,were enrolled in the present study. METHODS:MRI was performed on the limbic encephalitis patient using a 3.0T MR scanner. Three-dimensional SPGR T1-weighted images and DTI were acquired in the patient and controls. Data were analyzed using Matlab 7.0 and SPM2 software. MAIN OUTCOME MEASURES:Results from routine MRI scan with contrast enhancement of patient,as well as fractional anisotropy and mean diffusivity value map differences between patient and controls. RESULTS:Significant symmetric MRI signal intensity abnormalities were observed with routine MRI. Affected bilateral hippocampi and amygdala exhibited hypointense signals in T1WI and hyperintense signals in T2 images.The DTI study revealed decreased fractional anisotropy values in the bilateral alveus and fimbria of the hippocampus,bilateral internal and external capsules,white matter of the right prefrontal area,and left corona radiate in the patient compared with normal controls(P<0.001). Significantly increased fractional anisotropy,mean diffusivity,or decreased mean diffusivity were not observed in the patient,compared with controls. CONCLUSION:Secondary white matter damage to the hippocampal alveus and fimbria was apparent in the limbic encephalitis patient.In addition,other white matter fiber injuries surrounded the limbic structures,which were not attributed to secondary limbic system injuries.展开更多
BACKGROUND: Previous studies regarding primary progressive aphasia (PPA) have focused on progressive,non-fluent aphasia.Little information is available with regard to the use of diffusion tensor imaging compared with ...BACKGROUND: Previous studies regarding primary progressive aphasia (PPA) have focused on progressive,non-fluent aphasia.Little information is available with regard to the use of diffusion tensor imaging compared with conventional magnetic resonance imaging for the detection of subtle structural abnormalities.OBJECTIVE: To investigate and localize brain abnormalities in a Chinese patient with semantic dementia.DESIGN,TIME AND SETTING: A concurrent,non-randomized,case-controlled,neuroimaging,clinical trial was performed at the Department of Radiology,West China Hospital of Sichuan University in March 2009.PARTICIPANTS: One 75-year-old male patient,who was diagnosed with semantic dementia,and 21 age-and gender-matched healthy volunteers were recruited for the study.METHODS: Diffusion tensor imaging was used to determine mean diffusion (MD) and fractional anisotropy (FA) in the brains of the patient and the 21 healthy subjects.Voxel-based analysis of MD and FA values was performed using statistical parametric mapping.MAIN OUTCOME MEASURES: MD and FA value maps differences between patient and controls.RESULTS: MD was significantly increased in both cerebra,but was predominant on the left side and expanded to outside of the language-related region.Reduced MD was not detected in any of the brains.FA was shown to be decreased in the corpus callosum,but was increased in the basal ganglia.CONCLUSION: The present study provided clear in vivo magnetic imaging evidence of diffuse brain involvement in semantic dementia.Increases in MD were greater than in FA when brain diffusion alterations were detected,which suggested that MD could be a better marker of disease progression.展开更多
Phosphorus loss from fertilization is a significant source of pollution to freshwater lakes worldwide. Production of flowers, vegetables, staple food and vineyard in regions surrounding Dianchi, Erhai, Fuxian and Xing...Phosphorus loss from fertilization is a significant source of pollution to freshwater lakes worldwide. Production of flowers, vegetables, staple food and vineyard in regions surrounding Dianchi, Erhai, Fuxian and Xingyun lakes in Yunnan Province is large-scale. Previous studies have shown that annual fertilizer application rates (AFARs) were excessive in these regions. Significant amount of arable land near lakes has been used to build recreational parks with plants that receive less fertilization to reduce P loading. To answer whether rAFARs were associated with specific crops, AFARs of specific land uses were investigated through interviews. To estimate P loading, NaHCO3-P and NaOH-P concentrations were measured in 753 soil samples of selected layers (0 - 5, 5 - 20, 20 - 40 cm) in regions surrounding these lakes. Soil texture, pH, and cation exchange capacity (CEC) were analyzed to characterize soils. P loading was high ranging from 999 to 2094 mg P/kg as measured by NaOH-P, and levels of NaHCO3-P from 18.6 to 92.2 mg P/kg. AFARs to flower (4745 kg/ha), and vegetable (2967 kg/ha) were higher than those applied to staple food (945 kg/ha), and plants in recreation parks (200 kg/ha). The highest NaHCO3-P and NaOH-P concentrations in selected layers were associated with production of flowers, vegetables, and grapes. Although all layers of soils that were used for recreation parks in regions near Dianchi lake contained lower NaHCO3-P, NaOH-P was almost as high as with soils cultivated with flowers probably reflecting historical additions or differences in soil type. Here we show for the first time in local regions that the production of flowers, grapes and vegetables was a critical source contributing to the buildup of both readily available (NaHCO3-P) and reversibly available P (NaOH-P). Build-up of recreational parks with plants that receive less fertilization would be a long-term remediation to reduce P loading of soils in regions near Dianchi lake.展开更多
UNC-51-like kinase 1(ULK1),as a serine/threonine kinase,is an autophagic initiator in mammals and a homologous protein of autophagy related protein(Atg)1 in yeast and of UNC-51 in Caenorhabditis elegans.ULK1 is well-k...UNC-51-like kinase 1(ULK1),as a serine/threonine kinase,is an autophagic initiator in mammals and a homologous protein of autophagy related protein(Atg)1 in yeast and of UNC-51 in Caenorhabditis elegans.ULK1 is well-known for autophagy activation,which is evolutionarily conserved in protein transport and indispensable to maintain cell homeostasis.As the direct target of energy and nutrition-sensing kinase,ULK1 may contribute to the distribution and utilization of cellular resources in response to metabolism and is closely associated with multiple pathophysiological processes.Moreover,ULK1 has been widely reported to play a crucial role in human diseases,including cancer,neurodegenerative diseases,cardiovascular disease,and infections,and subsequently targeted small-molecule inhibitors or activators are also demonstrated.Interestingly,the non-autophagy function of ULK1 has been emerging,indicating that non-autophagy-relevant ULK1 signaling network is also linked with diseases under some specific contexts.Therefore,in this review,we summarized the structure and functions of ULK1 as an autophagic initiator,with a focus on some new approaches,and further elucidated the key roles of ULK1 in autophagy and non-autophagy.Additionally,we also discussed the relationships between ULK1 and human diseases,as well as illustrated a rapid progress for better understanding of the discovery of more candidate small-molecule drugs targeting ULK1,which will provide a clue on novel ULK1-targeted therapeutics in the future.展开更多
Enhancing the antibacterial properties of the currently used implant materials is a major concern of healthcare providers to minimize the impact of peri-implant infection and improve implant survival rates.In this stu...Enhancing the antibacterial properties of the currently used implant materials is a major concern of healthcare providers to minimize the impact of peri-implant infection and improve implant survival rates.In this study,titanium-copper sintered alloys(3 wt% and 5 wt%Cu) were developed for medical implant applications.The phase identification,microstructure,copper ions release,and wettability of these alloys were evaluated using X-ray diffraction(XRD),optical microscope(OM),scanning electron microscope(SEM),transmission electron microscope(TEM),energy-dispersive X-ray spectroscope(EDS),inductively coupled plasma spectroscope(ICP) and drop shape analyzer.The antibacterial activities of Ti-Cu alloys against Porphyromonas gingivalis and Streptococcus mutans were evaluated using inhibition zone assay,plate counting assay,live/dead fluorescent staining,SEM and reactive oxygen species(ROS) staining assay.The results demonstrated that Ti-Cu alloys are composed of α-Ti and Ti_(2)Cu phases that increased with increased Cu content of the alloy.Ti-Cu alloys exhibited antibacterial activity against both bacteria species in a time-dependent manner.The antibacterial rates of Ti-3Cu and Ti-5Cu after72 h were 57% and 70% against Porphyromonas gingivalis and 63% and 78% against Streptococcus mutans,respectively.The highest amount of Cu^(2+) released from these alloys was 0.3 mg·L^(-1) during the first 24 h,within the safe range.The copper ions release and ROS production were suggested as the main antibacterial mechanisms.Overall,Ti-Cu sintered alloys are promising materials for dental and orthopedic implants.展开更多
Objective:The aim of this study is to assess the neural interconnection between the acupoint"Chéngshān(承山BL57)"and sciatic nerve from the peripheral nervous system(PNS)to the central nervous system(C...Objective:The aim of this study is to assess the neural interconnection between the acupoint"Chéngshān(承山BL57)"and sciatic nerve from the peripheral nervous system(PNS)to the central nervous system(CNS).Methods:SD rats were systematically examined from the hip to the hind limb along the route of sciatic nerve with regional anatomical technique,and further traced from the BL57 and the trunk of sciatic nerve by the neural tracing technique with cholera toxin subunit B(CTB)and CTB conjugated Alexa Fluor 488 and 594(CTB-AF488/594).Results:After regional anatomy,it was found that the sciatic nerve ran down from the hip to the hind limb and sequentially sent out the tibial and sural branches respectively to the deep and superficial layers of BL57.The CTB labeling associated with both BL57 and sciatic nerve distributed in the same spinal segments and definite regions,including the sensory neurons in lumber 3(L3)-lumber 6(L6)dorsal root ganglia(DRGs),transganglionic axons mainly in the L3-L6 spinal dorsal horn,Clarke’s nucleus,and gracile nucleus,as well as motor neurons mainly in the L3-L6 spinal ventral horn.However,the amount of neural labeling was significantly less in the cases of BL57 than that of sciatic nerve.Conclusions:These results indicate that there is distinct sensory and motor interconnection between the BL57 and the sciatic nerve,which may potentially serve for the active role of the BL57 playing in meliorating the disorders of sciatic nerve.展开更多
Infection is a common problem after implantation,and the currently used Ti-based implants have insufficient antibacterial activities.The newly developed Zr-30Ta and Zr-25Ta-5Ti alloys exhibited good mechanical propert...Infection is a common problem after implantation,and the currently used Ti-based implants have insufficient antibacterial activities.The newly developed Zr-30Ta and Zr-25Ta-5Ti alloys exhibited good mechanical properties,low elastic moduli,and high corrosion resistance.In this work,their antibacterial activities and antibacterial mechanisms were investigated.The surface roughness,wettability,and charge of the alloys were evaluated using a profilometer,drop shape analyzer,and electrokinetic analyzer,respectively.The antibacterial activity against Streptococcus mutans and Porphyromonas gingivalis was investigated using the inhibition zone assay,plate count assay,live/dead staining,and scanning electron microscopy(SEM).The reactive oxygen species release(ROS)was evaluated using the 2’7’-dichlorodihydrofluorescein diacetate(DCFH-DA)assay.The results demonstrated that Zr-30Ta and Zr-25Ta-5Ti alloys had favorable smooth,hydrophilic,negatively charged surfaces that decreased bacteria adhesion and prevented biofilm formation.Zr-30Ta and Zr-25Ta-5Ti alloys also exhibited a time-dependent decrease in the bacteria adhesion and viability.Zr-30Ta and Zr-25Ta-5Ti alloys were also found to induce direct membrane damage and increase ROS production,resulting in significantly better antibacterial activities than CP-Ti.Zr-30Ta and Zr-25Ta-5Ti alloys exhibited comparable antibacterial activities.This work suggests that the newly developed Zr-30Ta and Zr-25Ta-5Ti alloys have good antibacterial activity against Streptococcus mutans and Porphyromonas gingivalis and are promising candidate materials for dental and orthopedic implants.展开更多
Insufficient early osteogenesis seriously affects the later stage osteogenic quality and osseointegration of dental implants.To promote early osteogenesis,we first designed a Ti dental implant with a built-in magnet(m...Insufficient early osteogenesis seriously affects the later stage osteogenic quality and osseointegration of dental implants.To promote early osteogenesis,we first designed a Ti dental implant with a built-in magnet(mTi)to produce a local static magnetic field(SMF).Then,a dental implantation system comprising the mTi implant and the superparamagnetic hydroxyapatite(HA:Yb/Ho-Fe,named HYH-Fe)particles was implanted into the alveolar bone of beagles.The results showed that the mTi+HYH-Fe group displayed better early osteogenesis and later stage osseointegration than the Ti+HA and mTi+HA groups.A combination of the local SMF(mTi)and superparamagnetic HYH-Fe particles had a positive effect on the pro-osteogenesis of Ti implants.The results also indicated that week 10 could be adopted as the key time point to evaluate the early osteogenic effect of the mTi+HYH-Fe implantation system,which would be a promising prospect for promotion of osteogenesis,in vivo tracking investigation of material-bone relationships,and clinical applications.展开更多
Self-supervised depth estimation approaches present excellent results that are comparable to those of the fully supervised approaches,by employing view synthesis between the target and reference images in the training...Self-supervised depth estimation approaches present excellent results that are comparable to those of the fully supervised approaches,by employing view synthesis between the target and reference images in the training data.ResNet,which serves as a backbone network,has some structural deficiencies when applied to downstream fields,because its original purpose was to cope with classification problems.The low-texture area also deteriorates the performance.To address these problems,we propose a set of improvements that lead to superior predictions.First,we boost the information flow in the network and improve the ability to learn spatial structures by improving the network structures.Second,we use a binary mask to remove the pixels in low-texture areas between the target and reference images to more accurately reconstruct the image.Finally,we input the target and reference images randomly to expand the dataset and pre-train it on ImageNet,so that the model obtains a favorable general feature representation.We demonstrate state-of-the-art performance on an Eigen split of the KITTI driving dataset using stereo pairs.展开更多
文摘BACKGROUD: Venous thromboembolism (VTE) including DVT and pulmonary embolism (PE) can be a devastating complication in postoperative patients which is also considered the most likely to be prevented. The proper assessment and effective identification of high risk factors of DVT are the basis for its prevention. We used the Caprini risk assessment model (Caprini RAM) based on many researches about the validation of DVT risk assessment model, and combined the recommendations reported in American College of Chest Physicians Evidence-Based Clinical Practice Guidelines (9th) and Chinese Orthopaedics Association guideline, to give surgical patients stratified prophylaxis. STUDY DESIGN: Between April 2016 and December 2016, we conducted a controlled trial study in 4 surgical departments including Gynecology Department, Joint Surgery, Spinal Surgery and Urology Surgery. 764 patients were included in control group, and 772 patients were included in intervention group. We used the original assessment and prevention methods in control group, while applied the stratified prophylaxis based on Caprini risk assessment level in intervention group. The incidence of DVT was analyzed using chi-square test, while patients’ hospital day was analyzed by independent t-tests. RESULTS: There was significantly difference in incidence rate of DVT between the two groups (13.09‰ vs. 2.59‰, P < 0.05), while the difference in hospital day was not significantly (10.63 ± 5.80 vs. 10.29 ± 5.18, P > 0.05). Most of the surgical patients were with moderate or high-risk (64.93%). CONCLUSIONS: Nurses could identify DVT risk factors in surgical patients using the Caprini risk assessment scale, and apply targeted stratified prophylaxis according to risk level. This model makes DVT risk assessment and intervention process more standardized and effective. It can also reduce incidence rate of DVT significantly. .
基金supported by the Natural Science Foundation of Hunan Province,China(No.2020JJ4732,2020JJ4933)the National Natural Science Foundation of China(No.52071343)。
基金supported by the National Natural Science Foundation of China(6120109661471137+4 种基金61501061)the Qing Lan Project of Jiangsu Province,the Science and Technology Program of Changzhou City(CJ20130026CE20135060CE20145055)the State Key Laboratory of Ocean Engineering(Shanghai Jiao Tong University)(1316)
文摘This paper addresses the extremal problem of the null subcarriers based Doppler scale estimation in underwater acoustic(UWA) orthogonal frequency division multiplexing(OFDM) communication. The cost function constructed of the total energy of null subcarriers through discrete Fourier transform(DFT) is proposed.The frequencies of null subcarriers are identified from non-uniform Doppler shift at each tentative scaling factor. Then it is proved that the cost function can be fitted as a quadratic polynomial near the global minimum. An accurate Doppler scale estimation is achieved by the location of the global scarifying precision and increasing the computation minimum through polynomial interpolation,without complexity. A shallow water experiment is conducted to demonstrate the performance of the proposed method. Excellent performance results are obtained in ultrawideband UWA channels with a relative bandwidth of 67%, when the transmitter and the receiver are moving at a relative speed of 5 kn, which validates the proposed method.
文摘The formulation of hard chromium plating from trivalent chromium electrolyte and its related process have been intensively studied in this work. Through optimized conditions, the coating hardness can achieve more than HV0.1900 without any treatment and HV0.11700 after heat treatment for five minutes at 300°C, and the thickness of hard chromium coating was about 100 μm. The hard chromium coatings show good adhesion on the carbon steel and low alloy structural steel. The corrosion resistance of hard chromium coatings was enhanced by the adding nanometer materials into trivalent chromium plating coatings. More than 120 hours salt spray corrosion resistance can be achieved with 40 to 50 microns thickness of trivalent chromium plating coatings.
文摘Aim To determine cephalometrically the mechanism of the treatment effects of non-extraction and multiloop edgewise archwire (MEAW) technique on postpeak ClassⅡ Division 1 patients. Methodology In this retrospective study, 16 postpeak ClassⅡ Division 1 patients successfully corrected using a non-extraction and MEAW technique were cephalometrically evaluated and compared with 16 matched control subjects treated using an extraction technique. Using CorelDRAW? software, standardized digital cephalograms pre-and post-active treatments were traced and a reference grid was set up. The superimpositions were based on the cranial base, the mandibular and the maxilla regions,and skeletal and dental changes were measured. Changes following treatment were evaluated using the paired-sample t-test. Student's t-test for unpaired samples was used to assess the differences in changes between the MEAW and the extraction control groups. Results The correction of the molar relationships comprised 54% skeletal change (mainly the advancement of the mandible) and 46% dental change. Correction of the anterior teeth relationships comprised 30% skeletal change and 70% dental change. Conclusion The MEAW technique can produce the desired vertical and sagittal movement of the tooth segment and then effectively stimulate mandibular advancement by utilizing the residual growth potential of the condyle.
基金the National Natural Science Foundation of China,No.30800263
文摘BACKGROUND:Limbic encephalitis is a rare syndrome that specifically affects the limbic system. Magnetic resonance imaging(MRI) has been typically used to detect brain changes in this disease. However,the mechanisms of limbic encephalitis-related white matter damage remain poorly understood. OBJECTIVE:To characterize white matter connectivity changes secondary to injuries of the limbic system in limbic encephalitis through combined application of diffusion tensor imaging(DTI) and voxel-based morphometry. DESIGN,TIME AND SETTING:A non-randomized,controlled,clinical,neuroimaging,DTI study was performed at the Department of Radiology,West China Hospital in December 2008. PARTICIPANTS:A male,46-year-old,limbic encephalitis patient,as well as 11 age- and gender-matched healthy volunteers,were enrolled in the present study. METHODS:MRI was performed on the limbic encephalitis patient using a 3.0T MR scanner. Three-dimensional SPGR T1-weighted images and DTI were acquired in the patient and controls. Data were analyzed using Matlab 7.0 and SPM2 software. MAIN OUTCOME MEASURES:Results from routine MRI scan with contrast enhancement of patient,as well as fractional anisotropy and mean diffusivity value map differences between patient and controls. RESULTS:Significant symmetric MRI signal intensity abnormalities were observed with routine MRI. Affected bilateral hippocampi and amygdala exhibited hypointense signals in T1WI and hyperintense signals in T2 images.The DTI study revealed decreased fractional anisotropy values in the bilateral alveus and fimbria of the hippocampus,bilateral internal and external capsules,white matter of the right prefrontal area,and left corona radiate in the patient compared with normal controls(P<0.001). Significantly increased fractional anisotropy,mean diffusivity,or decreased mean diffusivity were not observed in the patient,compared with controls. CONCLUSION:Secondary white matter damage to the hippocampal alveus and fimbria was apparent in the limbic encephalitis patient.In addition,other white matter fiber injuries surrounded the limbic structures,which were not attributed to secondary limbic system injuries.
文摘BACKGROUND: Previous studies regarding primary progressive aphasia (PPA) have focused on progressive,non-fluent aphasia.Little information is available with regard to the use of diffusion tensor imaging compared with conventional magnetic resonance imaging for the detection of subtle structural abnormalities.OBJECTIVE: To investigate and localize brain abnormalities in a Chinese patient with semantic dementia.DESIGN,TIME AND SETTING: A concurrent,non-randomized,case-controlled,neuroimaging,clinical trial was performed at the Department of Radiology,West China Hospital of Sichuan University in March 2009.PARTICIPANTS: One 75-year-old male patient,who was diagnosed with semantic dementia,and 21 age-and gender-matched healthy volunteers were recruited for the study.METHODS: Diffusion tensor imaging was used to determine mean diffusion (MD) and fractional anisotropy (FA) in the brains of the patient and the 21 healthy subjects.Voxel-based analysis of MD and FA values was performed using statistical parametric mapping.MAIN OUTCOME MEASURES: MD and FA value maps differences between patient and controls.RESULTS: MD was significantly increased in both cerebra,but was predominant on the left side and expanded to outside of the language-related region.Reduced MD was not detected in any of the brains.FA was shown to be decreased in the corpus callosum,but was increased in the basal ganglia.CONCLUSION: The present study provided clear in vivo magnetic imaging evidence of diffuse brain involvement in semantic dementia.Increases in MD were greater than in FA when brain diffusion alterations were detected,which suggested that MD could be a better marker of disease progression.
文摘Phosphorus loss from fertilization is a significant source of pollution to freshwater lakes worldwide. Production of flowers, vegetables, staple food and vineyard in regions surrounding Dianchi, Erhai, Fuxian and Xingyun lakes in Yunnan Province is large-scale. Previous studies have shown that annual fertilizer application rates (AFARs) were excessive in these regions. Significant amount of arable land near lakes has been used to build recreational parks with plants that receive less fertilization to reduce P loading. To answer whether rAFARs were associated with specific crops, AFARs of specific land uses were investigated through interviews. To estimate P loading, NaHCO3-P and NaOH-P concentrations were measured in 753 soil samples of selected layers (0 - 5, 5 - 20, 20 - 40 cm) in regions surrounding these lakes. Soil texture, pH, and cation exchange capacity (CEC) were analyzed to characterize soils. P loading was high ranging from 999 to 2094 mg P/kg as measured by NaOH-P, and levels of NaHCO3-P from 18.6 to 92.2 mg P/kg. AFARs to flower (4745 kg/ha), and vegetable (2967 kg/ha) were higher than those applied to staple food (945 kg/ha), and plants in recreation parks (200 kg/ha). The highest NaHCO3-P and NaOH-P concentrations in selected layers were associated with production of flowers, vegetables, and grapes. Although all layers of soils that were used for recreation parks in regions near Dianchi lake contained lower NaHCO3-P, NaOH-P was almost as high as with soils cultivated with flowers probably reflecting historical additions or differences in soil type. Here we show for the first time in local regions that the production of flowers, grapes and vegetables was a critical source contributing to the buildup of both readily available (NaHCO3-P) and reversibly available P (NaOH-P). Build-up of recreational parks with plants that receive less fertilization would be a long-term remediation to reduce P loading of soils in regions near Dianchi lake.
基金supported in part by National Natural Science Foundation of China (Grant Nos. 82172649 and 82173666)Shenzhen science and technology research and development funds (Grant No. JCYJ20210324094612035, China)the Key R&D Program of Sichuan Province (Grant No. 2021YFS0046, China)
文摘UNC-51-like kinase 1(ULK1),as a serine/threonine kinase,is an autophagic initiator in mammals and a homologous protein of autophagy related protein(Atg)1 in yeast and of UNC-51 in Caenorhabditis elegans.ULK1 is well-known for autophagy activation,which is evolutionarily conserved in protein transport and indispensable to maintain cell homeostasis.As the direct target of energy and nutrition-sensing kinase,ULK1 may contribute to the distribution and utilization of cellular resources in response to metabolism and is closely associated with multiple pathophysiological processes.Moreover,ULK1 has been widely reported to play a crucial role in human diseases,including cancer,neurodegenerative diseases,cardiovascular disease,and infections,and subsequently targeted small-molecule inhibitors or activators are also demonstrated.Interestingly,the non-autophagy function of ULK1 has been emerging,indicating that non-autophagy-relevant ULK1 signaling network is also linked with diseases under some specific contexts.Therefore,in this review,we summarized the structure and functions of ULK1 as an autophagic initiator,with a focus on some new approaches,and further elucidated the key roles of ULK1 in autophagy and non-autophagy.Additionally,we also discussed the relationships between ULK1 and human diseases,as well as illustrated a rapid progress for better understanding of the discovery of more candidate small-molecule drugs targeting ULK1,which will provide a clue on novel ULK1-targeted therapeutics in the future.
基金financially supported by the National Natural Science Foundation of China (Nos.51404302 and 51801003)the Natural Science Foundation of Hunan Province (Nos.2020JJ4732 and 2020JJ4933)。
文摘Enhancing the antibacterial properties of the currently used implant materials is a major concern of healthcare providers to minimize the impact of peri-implant infection and improve implant survival rates.In this study,titanium-copper sintered alloys(3 wt% and 5 wt%Cu) were developed for medical implant applications.The phase identification,microstructure,copper ions release,and wettability of these alloys were evaluated using X-ray diffraction(XRD),optical microscope(OM),scanning electron microscope(SEM),transmission electron microscope(TEM),energy-dispersive X-ray spectroscope(EDS),inductively coupled plasma spectroscope(ICP) and drop shape analyzer.The antibacterial activities of Ti-Cu alloys against Porphyromonas gingivalis and Streptococcus mutans were evaluated using inhibition zone assay,plate counting assay,live/dead fluorescent staining,SEM and reactive oxygen species(ROS) staining assay.The results demonstrated that Ti-Cu alloys are composed of α-Ti and Ti_(2)Cu phases that increased with increased Cu content of the alloy.Ti-Cu alloys exhibited antibacterial activity against both bacteria species in a time-dependent manner.The antibacterial rates of Ti-3Cu and Ti-5Cu after72 h were 57% and 70% against Porphyromonas gingivalis and 63% and 78% against Streptococcus mutans,respectively.The highest amount of Cu^(2+) released from these alloys was 0.3 mg·L^(-1) during the first 24 h,within the safe range.The copper ions release and ROS production were suggested as the main antibacterial mechanisms.Overall,Ti-Cu sintered alloys are promising materials for dental and orthopedic implants.
基金the project of National Key R&D Program of China:2019YFC1709103National Natural Science Foundation of China:81774211,81774432,81801561:82004492the Fundamental Research Funds for the Central Public Welfare Research Institutes:ZZ13-YQ-068,ZZ201914001,ZZ202017006,ZZ202017015。
文摘Objective:The aim of this study is to assess the neural interconnection between the acupoint"Chéngshān(承山BL57)"and sciatic nerve from the peripheral nervous system(PNS)to the central nervous system(CNS).Methods:SD rats were systematically examined from the hip to the hind limb along the route of sciatic nerve with regional anatomical technique,and further traced from the BL57 and the trunk of sciatic nerve by the neural tracing technique with cholera toxin subunit B(CTB)and CTB conjugated Alexa Fluor 488 and 594(CTB-AF488/594).Results:After regional anatomy,it was found that the sciatic nerve ran down from the hip to the hind limb and sequentially sent out the tibial and sural branches respectively to the deep and superficial layers of BL57.The CTB labeling associated with both BL57 and sciatic nerve distributed in the same spinal segments and definite regions,including the sensory neurons in lumber 3(L3)-lumber 6(L6)dorsal root ganglia(DRGs),transganglionic axons mainly in the L3-L6 spinal dorsal horn,Clarke’s nucleus,and gracile nucleus,as well as motor neurons mainly in the L3-L6 spinal ventral horn.However,the amount of neural labeling was significantly less in the cases of BL57 than that of sciatic nerve.Conclusions:These results indicate that there is distinct sensory and motor interconnection between the BL57 and the sciatic nerve,which may potentially serve for the active role of the BL57 playing in meliorating the disorders of sciatic nerve.
基金financially supported by the Natural Science Foundation of Hunan Province(Nos.2020JJ4732 and 2020JJ4933)the National Natural Science Foundation of China(No.52071343)
文摘Infection is a common problem after implantation,and the currently used Ti-based implants have insufficient antibacterial activities.The newly developed Zr-30Ta and Zr-25Ta-5Ti alloys exhibited good mechanical properties,low elastic moduli,and high corrosion resistance.In this work,their antibacterial activities and antibacterial mechanisms were investigated.The surface roughness,wettability,and charge of the alloys were evaluated using a profilometer,drop shape analyzer,and electrokinetic analyzer,respectively.The antibacterial activity against Streptococcus mutans and Porphyromonas gingivalis was investigated using the inhibition zone assay,plate count assay,live/dead staining,and scanning electron microscopy(SEM).The reactive oxygen species release(ROS)was evaluated using the 2’7’-dichlorodihydrofluorescein diacetate(DCFH-DA)assay.The results demonstrated that Zr-30Ta and Zr-25Ta-5Ti alloys had favorable smooth,hydrophilic,negatively charged surfaces that decreased bacteria adhesion and prevented biofilm formation.Zr-30Ta and Zr-25Ta-5Ti alloys also exhibited a time-dependent decrease in the bacteria adhesion and viability.Zr-30Ta and Zr-25Ta-5Ti alloys were also found to induce direct membrane damage and increase ROS production,resulting in significantly better antibacterial activities than CP-Ti.Zr-30Ta and Zr-25Ta-5Ti alloys exhibited comparable antibacterial activities.This work suggests that the newly developed Zr-30Ta and Zr-25Ta-5Ti alloys have good antibacterial activity against Streptococcus mutans and Porphyromonas gingivalis and are promising candidate materials for dental and orthopedic implants.
基金The authors acknowledge the support of funds from the National Natural Science Foundation of China(Grant No.31700828,32071335)the Research Funding from West China School/Hospital of Stomatology,Sichuan University(Grant No.RCDWJS2020-9,SKLOD202022).Special thanks to Dr.Li Chen for micro-CT analysis.
文摘Insufficient early osteogenesis seriously affects the later stage osteogenic quality and osseointegration of dental implants.To promote early osteogenesis,we first designed a Ti dental implant with a built-in magnet(mTi)to produce a local static magnetic field(SMF).Then,a dental implantation system comprising the mTi implant and the superparamagnetic hydroxyapatite(HA:Yb/Ho-Fe,named HYH-Fe)particles was implanted into the alveolar bone of beagles.The results showed that the mTi+HYH-Fe group displayed better early osteogenesis and later stage osseointegration than the Ti+HA and mTi+HA groups.A combination of the local SMF(mTi)and superparamagnetic HYH-Fe particles had a positive effect on the pro-osteogenesis of Ti implants.The results also indicated that week 10 could be adopted as the key time point to evaluate the early osteogenic effect of the mTi+HYH-Fe implantation system,which would be a promising prospect for promotion of osteogenesis,in vivo tracking investigation of material-bone relationships,and clinical applications.
基金Project supported by the Key R&D Program of Guangdong Province,China(No.2019B01015000)the National Natural Science Foundation of China(No.61902201)。
文摘Self-supervised depth estimation approaches present excellent results that are comparable to those of the fully supervised approaches,by employing view synthesis between the target and reference images in the training data.ResNet,which serves as a backbone network,has some structural deficiencies when applied to downstream fields,because its original purpose was to cope with classification problems.The low-texture area also deteriorates the performance.To address these problems,we propose a set of improvements that lead to superior predictions.First,we boost the information flow in the network and improve the ability to learn spatial structures by improving the network structures.Second,we use a binary mask to remove the pixels in low-texture areas between the target and reference images to more accurately reconstruct the image.Finally,we input the target and reference images randomly to expand the dataset and pre-train it on ImageNet,so that the model obtains a favorable general feature representation.We demonstrate state-of-the-art performance on an Eigen split of the KITTI driving dataset using stereo pairs.
