Hepatic encephalopathy(HE)is a neurological condition that occurs as a complication of liver dysfunction that involves sensorimotor symptoms in addition to cognitive and behavioral changes,particularly in cases of sev...Hepatic encephalopathy(HE)is a neurological condition that occurs as a complication of liver dysfunction that involves sensorimotor symptoms in addition to cognitive and behavioral changes,particularly in cases of severe liver disease or cirrhosis.Previous studies have reported spatially distributed structural and functional abnormalities related to HE,but the exact relationship between the structural and functional alterations with respect to disease progression remains unclear.In this study,we performed surface-based cortical thickness comparisons and functional connectivity(FC)analyses between three cross-sectional groups:healthy controls(HC,N¼51),patients with minimal hepatic en-cephalopathy(MHE,N¼50),patients with overt hepatic encephalopathy(OHE,N¼51).In addition to the distributed cortical thinning that is extensively thought to be associated with cognitive decline in HE,we found significant cortical thickening in the left para-hippocampal gyrus cortex in the OHE group(p<0.001,p¼0.009)as compared to the HC and MHE group respectively,which is further corroborated by the significant correlation between the cortical thickness and digit symbol test(DST)scores.Furthermore,the decreased FC between the right postcentral gyrus and several sensory regions(bilateral somatosensory and visual cortices)was found to be significant in MHE patients as compared to the HC group.Our results revealed cross-sectional structural and functional variations concerning disease progression across different subsystems(e.g.,visual,motor and sensory),providing evidence that can potentially explain the mechanisms underlying the sensorimotor and cognitive deficits related to HE.展开更多
BACKGROUND Mild cognitive impairment(MCI)is a transitional state between normal aging and Alzheimer's disease(AD),characterized by subtle cognitive decline.Amnestic MCI(aMCI),in particular,is a critical precursor ...BACKGROUND Mild cognitive impairment(MCI)is a transitional state between normal aging and Alzheimer's disease(AD),characterized by subtle cognitive decline.Amnestic MCI(aMCI),in particular,is a critical precursor often progressing to AD.There is growing interest in understanding the neuroanatomical correlates of aMCI,especially the role of gray matter volume(GMV)in cognitive and motor function decline.This study hypothesized that aMCI patients will exhibit reduced GMV,particularly in brain regions associated with cognition and motor control,impacting both cognitive performance and motor abilities.AIM To investigate the association of GMV with cognitive and motor functions in aMCI.METHODS In this cross-sectional study conducted from March 2022 to March 2024,45 aMCI patients and 45 normal controls from our Department of Geratology were enrolled.Voxel-based morphometry was used to compare GMV between groups.Correlation of differential GMV with cognitive scores and gait parameters was assessed via partial correlation analysis.Linear regression was used to assess associations between whole-brain GMV and gait measures.RESULTS GMV of aMCI region of interest(ROI)1 and ROI2 was negatively correlated with Activities of Daily Living(ADL)score.GMV of ROI6 was positively correlated with the total scores of Mini-Mental State Examination and Cambridge Cognitive Examination-Chinese Version(CAMCOG-C)and negatively correlated with ADL score.In the partial correlation analysis of cognitive and motor function parameters,age,gender,educational level,height,and weight were controlled,and the results showed that CAMCOG-C was negatively correlated with Dual Task of Time Up and Go Test(TUG)duration in the aMCI group.The volume of the left occipital gray matter in the aMCI group was negatively correlated with TUG.GMV of the bilateral frontal gyrus,right orbitofrontal gyrus,right occipital cleft,right supraoccipital gyrus,and left anterior central gyrus was positively correlated with walking speed.CONCLUSION GMV reduction in aMCI correlates with impaired cognition and motor function,emphasizing key roles for prefrontal,occipital,and central regions in gait disorders.展开更多
Background:Subcortical ischemic vascular dementia(SIVD)is a common subtype of vascular dementia.Currently,the bilateral common carotid artery stenosis(BCAS)mouse model is the most suitable SIVD rodent model.In this st...Background:Subcortical ischemic vascular dementia(SIVD)is a common subtype of vascular dementia.Currently,the bilateral common carotid artery stenosis(BCAS)mouse model is the most suitable SIVD rodent model.In this study,we investigated the functional and structural impairments in the hippocampus 1 month after BCAS.Methods:We used behavioral tests,laser speckle flowmetry,long-term potentiation,histochemical staining,molecular experiments,and voxel-based morphometry to evaluate the hippocampal impairments.Results:Behavioral studies revealed that BCAS mice exhibited worse performance.Laser speckle flowmetry detected an obvious decrease in cerebral blood flow.The synaptic plasticity of the perforant path-dentate gyrus pathway was inhibited.Decreased fractional anisotropy and increased mean diffusivity were detected in the hippocampus via diffusion tensor imaging data.A reduction in gray matter volume,which was most prominent in the hippocampus and its surrounding areas,was de-tected via voxel-based morphometry analysis.Impairments in cell morphology and myelin integrity were validated using histochemical staining and molecular biology techniques.In addition,the numbers of GFAP+astrocytes and Iba1+microglia in-creased in the hippocampus.Conclusions:Overall,our study demonstrates early functional and structural impair-ments in the hippocampus contributing to learning and memory deficits after 1 month of BCAS,indicating that the hippocampus is vulnerable to chronic cerebral ischemia.展开更多
AIM:To elucidate the neuropathological mechanisms underlying diabetic vitreous hemorrhage(DVH)and its correlation with clinical characteristics.METHODS:Twenty-one individuals with DVH(male/female 12/9;mean age 52.29&#...AIM:To elucidate the neuropathological mechanisms underlying diabetic vitreous hemorrhage(DVH)and its correlation with clinical characteristics.METHODS:Twenty-one individuals with DVH(male/female 12/9;mean age 52.29±11.66y)were selected,alongside 21 appropriately matched controls with diabetes mellitus(DM).Voxel-based morphometry(VBM)techniques were employed to identify aberrant functional regions in the brain.Receiver operating characteristic(ROC)curves were utilized for classification based on the average VBM values of the two groups,and Pearson correlation analysis was conducted to assess the relationship between average VBM values in distinct brain regions and clinical manifestations.RESULTS:Relative to the DM controls,DVH patients exhibited reduced VBM values in the right superior temporal pole,the right superior temporal gyrus,the right medial orbital frontal gyrus,and the left superior frontal gyrus.Furthermore,ROC curve analysis of these four brain regions in DVH patients demonstrated a high degree of accuracy,as indicated by the area under the curve.The average VBM value in each of these regions exhibited a negative correlation with both the duration of DVH and the score on the Hospital Anxiety and Depression Scale(HADS).CONCLUSION:Pathological alterations in four distinct brain regions are observed in patients with DVH,potentially reflecting neuropathological changes associated with this condition.展开更多
Objective:Magnetic resonance imaging(MRI)studies have demonstrated anatomical and functional alterations of brain regions in patients with migraine,and the efficacy of acupuncture for migraine could regulate these abn...Objective:Magnetic resonance imaging(MRI)studies have demonstrated anatomical and functional alterations of brain regions in patients with migraine,and the efficacy of acupuncture for migraine could regulate these abnormal alterations.However,its pathogenesis remains ambiguous,and inconsistent results have been reported.The purpose of this study was to explore abnormal structural and functional alterations in patients with migraine using voxel-based morphometry(VBM)analysis and a seed-based functional connectivity(FC)approach and to provide a basis for future research.Methods:The study recruited 34 patients with migraine and 38 healthy controls who underwent structural and resting-state functional magnetic resonance imaging(fMRI).VBM was evaluated across the whole brain,and group differences in the gray matter(GM)were compared.The significantly altered GM volumes considered as the seeding area were further calculated for the FC of the whole brain.The correlation between structural or functional changes of the brain and clinical features was also evaluated.Results:Patients with migraine manifested higher GM volumes in the left occipital lobe than healthy controls.Seed-based analyses demonstrated reduced FC between the left occipital lobe and right inferior frontal gyrus,extending to the anterior cingulate cortex(ACC)and right insula.Decreased FC in the left ACC was positively correlated with visual analog scale(VAS)and self-rating anxiety scale(SAS).展开更多
The objective of this study was to investigate whether treatment with Tribulus terrestris(Tt)has any impact on the testicular morphology and function in a rodent model.Twenty male rats were divided into a control grou...The objective of this study was to investigate whether treatment with Tribulus terrestris(Tt)has any impact on the testicular morphology and function in a rodent model.Twenty male rats were divided into a control group and a group receiving 100 mg kg^(-1) body weight of Tt supplementation.After 4o days of experiment,the animals were submitted to euthanasia;epididymal tail spermatozoa were collected;and spermatozoa concentration,motility,and viability were analyzed.In addition,testicles were collected and processed for histomorphometrical analyses.Data were compared using the Student's t-test and considered significant when P<O.05.Spermatozoa concentration,motility,and viability showed no difference between the groups.Further,testicular weight and volume,seminiferous tubule diameter,tunica propria surface density,seminiferous epithelium surface density,and intertubular compartment surface density were statistically similar between the groups.However,seminiferous epithelium height and tubular lumen surface density were augmented in animals treated with Tt.Treatment with Tt does not cause a major impact on testicular morphology,promoting only subtle modifications.No difference on spermatozoa parameters was observed.展开更多
BACKGROUND Major depressive disorder(MDD)in adolescents and young adults contributes significantly to global morbidity,with inconsistent findings on brain structural changes from structural magnetic resonance imaging ...BACKGROUND Major depressive disorder(MDD)in adolescents and young adults contributes significantly to global morbidity,with inconsistent findings on brain structural changes from structural magnetic resonance imaging studies.Activation likeli-hood estimation(ALE)offers a method to synthesize these diverse findings and identify consistent brain anomalies.METHODS We performed a comprehensive literature search in PubMed,Web of Science,Embase,and Chinese National Knowledge Infrastructure databases for neuroi-maging studies on MDD among adolescents and young adults published up to November 19,2023.Two independent researchers performed the study selection,quality assessment,and data extraction.The ALE technique was employed to synthesize findings on localized brain function anomalies in MDD patients,which was supplemented by sensitivity analyses.RESULTS Twenty-two studies comprising fourteen diffusion tensor imaging(DTI)studies and eight voxel-based morphome-try(VBM)studies,and involving 451 MDD patients and 465 healthy controls(HCs)for DTI and 664 MDD patients and 946 HCs for VBM,were included.DTI-based ALE demonstrated significant reductions in fractional anisotropy(FA)values in the right caudate head,right insula,and right lentiform nucleus putamen in adolescents and young adults with MDD compared to HCs,with no regions exhibiting increased FA values.VBM-based ALE did not demonstrate significant alterations in gray matter volume.Sensitivity analyses highlighted consistent findings in the right caudate head(11 of 14 analyses),right insula(10 of 14 analyses),and right lentiform nucleus putamen(11 of 14 analyses).CONCLUSION Structural alterations in the right caudate head,right insula,and right lentiform nucleus putamen in young MDD patients may contribute to its recurrent nature,offering insights for targeted therapies.展开更多
Context and Justification: Reconstructive spine surgery and the design of implants depend on disc and vertebral measurements, which vary according to racial groups and geographic areas. This variability underscores th...Context and Justification: Reconstructive spine surgery and the design of implants depend on disc and vertebral measurements, which vary according to racial groups and geographic areas. This variability underscores the importance of studying the morphometric characteristics specific to each population. Research Objective: The primary aim of this research was to determine the measurements of spinal components in the Congolese population in order to establish references suitable for local clinical practice. Materials and Methods: Congolese individuals, free from any spinal disorders, participated in a study on vertebral and disc morphology of the lumbar spine after providing informed consent. They underwent computed tomography examinations at medical imaging centers in Brazzaville. The parameters studied included: in axial sections, the transverse diameter (TDb) and sagittal diameter (SDb) of the vertebral bodies, the pedicular transverse diameter (TDp), and in sagittal reconstructions: the height of the vertebral bodies (Hb) and intervertebral discs (Hd). Results: The sample size consisted of 100 subjects (70 men and 30 women), with an average age of 24.47 ± 3.72 years (18 - 30 years). Cranio-caudally, the TDb, DSb, TDp, and Hd showed increasing values, while Hb values were decreasing. In L1, values for both sexes were: TDb = 39.3 ± 3 mm;DSb = 27.3 ± 2.9 mm;Hb = 26.6 ± 2.1 mm;TDp = 8.2 ± 1.8 mm;in L5: TDb = 50.3 ± 4 mm;DSb = 33.6 ± 2.7 mm;Hb = 25.7 ± 2.2 mm;TDp = 14.8 ± 2.1 mm. The Hd values were 8.1 ± 2.1 mm for L1 - L2 and 11.1 ± 2 mm for L5 - S1. Conclusion: Reconstructive spine surgery and the design of implants depend on disc and vertebral measurements, which vary according to racial groups and geographic areas. This variability underscores the importance of studying the morphometric characteristics specific to each population.展开更多
Objective To investigate cerebral structural signatures of the bulbar-and spinal-onset amyotrophic lateral sclerosis(ALS) using voxel-based morphometry on magnetic resonance imaging.Methods The MR structural images of...Objective To investigate cerebral structural signatures of the bulbar-and spinal-onset amyotrophic lateral sclerosis(ALS) using voxel-based morphometry on magnetic resonance imaging.Methods The MR structural images of the brain were obtained from 65 ALS patients(15 bulbar-onset, 50 spinalonset) and 65 normal controls(NC) on a 3.0 T MRI system. Gray matter(GM) volume changes were investigated by voxel-based morphometry, and the distribution of the brain regions with volume changes was compared between ALS and normal controls, as well as between bulbar-onset and spinal-onset ALS based on Neuromorphometrics atlas.Results On voxel-level the decreased volume of brain regions in ALS patients was located in the right precentral gyrus(r Prc Gy) and right middle frontal gyrus compared with that in NC. The bulbar-onset ALS presented extramotor cortex atrophy(fronto-temporal pattern), including left medial orbital gyrus, left inferior temporal gyrus and right middle temporal gyrus; the spinal-onset ALS suffered from motor cortex atrophy(r Prc Gy dominance) and extra-motor cortex atrophy(fronto-temporal and extra-fronto-temporal pattern) compared with NC. The spinal-onset ALS featured by GM volume loss of left postcentral gyrus and bulbar-onset ALS featured by GM volume loss of left middle temporal gyrus compared with each other. Conclusions The asymmetric GM atrophy of the motor cortex and extra-motor cortex represents the common MRI structural signatures of spinal-onset ALS, and sole extra-motor cortex atrophy represents the structural signatures of bulbar-onset ALS. The present study also demonstrated that the pattern of GM damage is likely to distribute wider in spinal-onset ALS than in bulbar-onset ALS.展开更多
Chromosomal evolution is widely considered an important driver of speciation because it can promote the establishment of reproductive barriers.Karyotypic reorganization is also expected to affect the mea n phe no type...Chromosomal evolution is widely considered an important driver of speciation because it can promote the establishment of reproductive barriers.Karyotypic reorganization is also expected to affect the mea n phe no type,as well as its developme nt and patter ns of phenotypic in tegrati on,through processes such as variation in genetic linkage between quantitative trait loci or between regulatory regions and their targets.Here we explore the relationship between chromosomal evolution and phenotypic integration by analyzing a well-known house mouse parapatric contact zone between a highly derived Robertsonian(Rb)race(2n=22)and populations with standard karyotype(2n=40).Populations with hybrid karyotypes are scattered throughout the hybrid zone connecting the two parental races.Using mandible shape data and geometric morphometries,we test the hypothesis that patter ns of in tegration progressively diverge from the"normal"integration pattern observed in the standard race as they accumulate Rb fusions.We find that the main pattern of integration observed between the posterior and anterior part of the mandible can be largely attributed to allometry.We find no support for a gradual increase in divergence from normal patterns of integration as fusions accumulate.Surprisingly,however,we find that the derived Rb race(2n=22)has a distinct allometric trajectory compared with the standard race.Our results suggest that either individual fusions disproportionately affect patterns of integration or that there are mechanisms which"purge"extreme variants in hybrids(e.g.reduced fitness of hybrid shape).展开更多
Selective pressures favor morphologies that are adapted to distinct ecologies,resulting in trait partition!ng among ecomorphotypes.However,the effects of these selective pressures vary across taxa,especially because m...Selective pressures favor morphologies that are adapted to distinct ecologies,resulting in trait partition!ng among ecomorphotypes.However,the effects of these selective pressures vary across taxa,especially because morphology is also influenced by factors such as phylogeny,body size,and functional trade-offs.In this study,we examine how these factors impact functional diversification in mammals.It has been proposed that trait partitioning among mammalian ecomorphotypes is less pronoun ced at small body sizes due to biomecha nical,energetic,and environ mental factors that favor a"generalist"body plan,whereas larger taxa exhibit more substantial functional adaptations.We title this the Diverge nee Hypothesis(DH)because it predicts greater morphological divergence among ecomorphotypes at larger body sizes.We test DH by using phylogenetic comparative methods to examine the postcranial skeletons of 129 species of taxonomically diverse,small-tomedium-sized(<15 kg)mammals,which we categorize as either"tree-dwellers"or"ground-dwellers."In some analyses,the morphologies of ground-dwellers and tree-dwellers suggest greater between-group differentiation at larger sizes,providing some evidence for DH.However,this trend is n either particularly strong nor supported by all an alyses.In stead,a more pronoun ced patter n emerges that is distinct from the predictions of DH:within-group phenotypic disparity increases with body size in both ground-dwellers and tree-dwellers,driven by morphological outliers among"medium'-sized mammals.Thus,evolutionary increases in body size are more closely linked to increases in within-locomotor-group disparity tha n to in creases in betwee n-group disparity.We discuss biomechanical and ecological factors that may drive these evolutionary patter ns,and we emphasize the significant evolutionary influences of ecology and body size on phenotypic diversity.展开更多
Aim： To quantitatively study the histological changes of the testis and epididymis as a result of a drastic reduction of testosterone secretion. Methods： Fourteen adult Sprague-Dawley rats were injected intraperiton...Aim： To quantitatively study the histological changes of the testis and epididymis as a result of a drastic reduction of testosterone secretion. Methods： Fourteen adult Sprague-Dawley rats were injected intraperitoneally with ethane dimethane sulfonate （EDS, 75 mg/kg） and the same number of animals were injected with normal saline as a control. At days 7 and 12 （after treatment）, respectively, half of the animals from each group were killed. The testes and epididymides were removed and tissue blocks embedded in methacrylate resin. The cell number per testis was estimated using the stereological optical disector and some other parameters were obtained using other morphometric methods. Results： The EDS treatment resulted in an almost complete elimination of Leydig cells but had no effect on the numbers of Sertoli cells per testis. At day 7 after EDS treatment, many elongated spermatids were retained in the seminiferous epithelium and many round spermatids could be seen in the epididymal ducts. At day 12, a looser arrangement of spermatids and spermatocytes became evident, with apparent narrow empty spaces being formed between germ cells in an approximately radial direction towards the tubule lumen; the numbers （per testis） of non-type B spermatogonia and spermatocytes were similar to controls, whereas that of type B spermatogonia increased by 59%, and that of early round, elongating and late elongated spermatids decreased by 37%, 72% and 52%, respectively. Conclusion： The primary spermatogenic lesions following EDS administration were （i） spermiation failure and （ii） detachment of spermatids and spermatocytes associated with impairment in spermiogenesis and meiosis.展开更多
INTRODUCTION Hepatocellular carcinoma(HCC)is closely relatedwith hepatitis and cirrhosis.In order to investigatethe pathogenesis and early pathologic diagnosis ofHCC,HCC and related lesions were analyzedqualitively an...INTRODUCTION Hepatocellular carcinoma(HCC)is closely relatedwith hepatitis and cirrhosis.In order to investigatethe pathogenesis and early pathologic diagnosis ofHCC,HCC and related lesions were analyzedqualitively and quantitively by automatic imageanalysor and immunohistochemical assay.展开更多
A systematic characterization of the similarities and differences among different methods for detecting structural brain abnormalities in schizophrenia,such as voxel-based morphometry(VBM),tensor-based morphometry(TBM...A systematic characterization of the similarities and differences among different methods for detecting structural brain abnormalities in schizophrenia,such as voxel-based morphometry(VBM),tensor-based morphometry(TBM),and projection-based thickness(PBT),is important for understanding the brain pathology in schizophrenia and for developing effective biomarkers for a diagnosis of schizophrenia.However,such studies are still lacking.Here,we performed VBM,TBM,and PBT analyses on T1-weighted brain MR images acquired from 116 patients with schizophrenia and 116 healthy controls.We found that,although all methods detected wide-spread structural changes,different methods captured different information-only 10.35%of the grey matter changes in cortex were detected by all three methods,and VBM only detected 11.36%of the white matter changes detected by TBM.Further,pattern classification between patients and controls revealed that combining different measures improved the classification accuracy(81.9%),indicating that fusion of different structural measures serves as a better neuroimaging marker for the objective diagnosis of schizophrenia.展开更多
Hepatic myelopathy is a complication seen in patients with chronic liver failure with physiologic or iatrogenic portosystemic shunting. The main symptom is progressive lower limb dyskinesia. The role of the brain moto...Hepatic myelopathy is a complication seen in patients with chronic liver failure with physiologic or iatrogenic portosystemic shunting. The main symptom is progressive lower limb dyskinesia. The role of the brain motor control center in hepatic myelopathy is unknown. This study aimed to investigate the gray matter changes in patients with hepatic myelopathy secondary to transjugular intrahepatic portosystemic shunt and to examine their clinical relevance. This was a cross-sectional study. Twenty-three liver failure patients with hepatic myelopathy(hepatic myelopathy group), 23 liver failure patients without hepatic myelopathy(non-hepatic myelopathy group) after transjugular intrahepatic portosystemic shunt, and 23 demographically matched healthy volunteers were enrolled from March 2014 to November 2016 at Xijing Hospital, Air Force Military Medical University(Fourth Military Medical University), China. High-resolution magnetization-prepared rapid gradient-echo brain imaging was acquired. Group differences in regional gray matter were assessed using voxel-based morphometry analysis. The relationship between aberrant gray matter and motor characteristics was investigated. Results demonstrated that compared with the non-hepatic myelopathy group, gray matter volume abnormalities were asymmetric, with decreased volume in the left insula(P = 0.003), left thalamus(P = 0.029), left superior frontal gyrus(P = 0.006), and right middle cingulate cortex(P = 0.021), and increased volume in the right caudate nucleus(P = 0.017), corrected with open-source software. The volume of the right caudate nucleus in the hepatic myelopathy group negatively correlated with the lower limb clinical rating of the Fugl-Meyer Assessment(r = –0.53, P = 0.01). Compared with healthy controls, patients with and without hepatic myelopathy exhibited overall increased gray matter volume in both thalami, and decreased gray matter volume in both putamen, as well as in the globus pallidus, cerebellum, and vermis. The gray matter abnormalities we found predominantly involved motor-related regions, and may be associated with motor dysfunction. An enlarged right caudate nucleus might help to predict weak lower limb motor performance in patients with preclinical hepatic myelopathy after transjugular intrahepatic portosystemic shunt. This study was approved by the Ethics Committee of Xijing Hospital, Air Force Military Medical University(Fourth Military Medical University), China(approval No. 20140227-6) on February 27, 2014.展开更多
After natural or artificial insemination, the spermatozoon starts a journey from the site of deposition to the place of fertilization. However, only a small subset of the spermatozoa deposited achieves their goal： to...After natural or artificial insemination, the spermatozoon starts a journey from the site of deposition to the place of fertilization. However, only a small subset of the spermatozoa deposited achieves their goal： to reach and fertilize the egg. Factors involved in controlling sperm transport and fertilization include the female reproductive tract environment, cell-cell interactions, gene expression, and phenotypic sperm traits. Some of the significant determinants of fertilization are known （i.e., motility or DNA status）, but many sperm traits are still indecipherable. One example is the influence of sperm dimensions and shape upon transport within the female genital tract towards the oocyte. Biophysical associations between sperm size and motility may influence the progression of spermatozoa through the female reproductive tract, but uncertainties remain concerning how sperm morphology influences the fertilization process, and whether only the sperm dimensions per se are involved. Moreover, such explanations do not allow the possibility that the female tract is capable of distinguishing fertile spermatozoa on the basis of their morphology, as seems to be the case with biochemical, molecular, and genetic properties. This review focuses on the influence of sperm size and shape in evolution and their putative role in sperm transport and selection within the uterus and the ability to fertilize the oocyte.展开更多
The rain shadow regions requisite a comprehensive watershed development and management plan for sustainable water resources management. The Pambar River Basin （PRB） lies on the rain shadow region of the southern Wes...The rain shadow regions requisite a comprehensive watershed development and management plan for sustainable water resources management. The Pambar River Basin （PRB） lies on the rain shadow region of the southern Western Ghats, India, where climate showed marked intra-basin variation. A morphometric analysis was done to evaluate the drainage characteristics of PRB using topographical maps and digital elevation data. PRB was divided into eighteen 4th order basins （SB1-SB18）, distributed along various climatic gradients. Lower order streams mostly dominate PRB and drainage pattern is a function of relief and structure. The terrain is highly dissected and prone to soil erosion during heavy storms and the elongated shape of PRB enables easier flood management. The influence of climate on drainage characteristics was evidently emphasized in basin morphometry. Four distinctively different classes were identified based on the morphometric similarities. The significance of morphometric analysis on the hydrological characterization is discussed and the relevance of the present study in water harvesting has been explicated.展开更多
Specific patterns of brain atrophy may be helpful in the diagnosis of Alzheimer＇s disease （AD）. In the present study, we set out to evaluate the utility of grey-matter volume in the classification of AD and amnesti...Specific patterns of brain atrophy may be helpful in the diagnosis of Alzheimer＇s disease （AD）. In the present study, we set out to evaluate the utility of grey-matter volume in the classification of AD and amnestic mild cognitive impairment （aMCI） compared to normal control （NC）individuals. Voxel-based morphometric analyses were performed on structural MRIs from 35 AD patients, 27 aMCI patients, and 27 NC participants. A two-sample two-tailed t-test was computed between the NC and AD groups to create a map of abnormal grey matter in AD. The brain areas with significant differences were extracted as regions of interest （ROIs）, and the grey-matter volumes in the ROIs of the aMCI patients were included to evaluate the patterns of change across different disease severities. Next, correlation analyses between the grey-matter volumes in the ROIs and all clinical variables were performed in aMCI and AD patients to determine whether they varied with disease progression. The results revealed significantly decreased grey matter in the bilateral hippocampus/ parahippocampus, the bilateral superior/middle temporal gyri, and the right precuneus in AD patients.The grey-matter volumes with clinical variables were positively correlated Finally, we performed exploratory linear discriminative analyses to assess the classifying capacity of grey-matter volumes in the bilateral hippocampus and parahippocampus among AD, aMCI, and NC. Leave-one-out cross- validation analyses demonstrated that grey-matter volumes in hippocampus and parahippocampus accurately distinguished AD from NC. These findings indicate that grey-matter volumes are useful in the classification of AD.展开更多
基金the National Natural Scientific Foundation of China(82071994,82202249)Tianjin Health High Level Talent Selection and Training Project(TJSQNYXXR-D2-143)+4 种基金Natural Scientific Foundation of Tianjin(21CYBJC01580,21JCQNJC01480)Tianjin Health Research Project(TJWJ2023QN031,TJWJ2023XK012)Tianjin Health Science and technology project(Specific projects of key disciplines)(TJWJ2022XK019)Tianjin Key Medical Discipline(Specialty)Construction Project(TJYXZDXK-041A)Tianjin Natural Science Foundation(21JCYBJC01290).
文摘Hepatic encephalopathy(HE)is a neurological condition that occurs as a complication of liver dysfunction that involves sensorimotor symptoms in addition to cognitive and behavioral changes,particularly in cases of severe liver disease or cirrhosis.Previous studies have reported spatially distributed structural and functional abnormalities related to HE,but the exact relationship between the structural and functional alterations with respect to disease progression remains unclear.In this study,we performed surface-based cortical thickness comparisons and functional connectivity(FC)analyses between three cross-sectional groups:healthy controls(HC,N¼51),patients with minimal hepatic en-cephalopathy(MHE,N¼50),patients with overt hepatic encephalopathy(OHE,N¼51).In addition to the distributed cortical thinning that is extensively thought to be associated with cognitive decline in HE,we found significant cortical thickening in the left para-hippocampal gyrus cortex in the OHE group(p<0.001,p¼0.009)as compared to the HC and MHE group respectively,which is further corroborated by the significant correlation between the cortical thickness and digit symbol test(DST)scores.Furthermore,the decreased FC between the right postcentral gyrus and several sensory regions(bilateral somatosensory and visual cortices)was found to be significant in MHE patients as compared to the HC group.Our results revealed cross-sectional structural and functional variations concerning disease progression across different subsystems(e.g.,visual,motor and sensory),providing evidence that can potentially explain the mechanisms underlying the sensorimotor and cognitive deficits related to HE.
基金Supported by Zhejiang Province Traditional Chinese Medicine Science and Technology Plan Project,No.2023ZL460Zhejiang Province Traditional Chinese Medicine Modernization Special Project,No.2021ZX011。
文摘BACKGROUND Mild cognitive impairment(MCI)is a transitional state between normal aging and Alzheimer's disease(AD),characterized by subtle cognitive decline.Amnestic MCI(aMCI),in particular,is a critical precursor often progressing to AD.There is growing interest in understanding the neuroanatomical correlates of aMCI,especially the role of gray matter volume(GMV)in cognitive and motor function decline.This study hypothesized that aMCI patients will exhibit reduced GMV,particularly in brain regions associated with cognition and motor control,impacting both cognitive performance and motor abilities.AIM To investigate the association of GMV with cognitive and motor functions in aMCI.METHODS In this cross-sectional study conducted from March 2022 to March 2024,45 aMCI patients and 45 normal controls from our Department of Geratology were enrolled.Voxel-based morphometry was used to compare GMV between groups.Correlation of differential GMV with cognitive scores and gait parameters was assessed via partial correlation analysis.Linear regression was used to assess associations between whole-brain GMV and gait measures.RESULTS GMV of aMCI region of interest(ROI)1 and ROI2 was negatively correlated with Activities of Daily Living(ADL)score.GMV of ROI6 was positively correlated with the total scores of Mini-Mental State Examination and Cambridge Cognitive Examination-Chinese Version(CAMCOG-C)and negatively correlated with ADL score.In the partial correlation analysis of cognitive and motor function parameters,age,gender,educational level,height,and weight were controlled,and the results showed that CAMCOG-C was negatively correlated with Dual Task of Time Up and Go Test(TUG)duration in the aMCI group.The volume of the left occipital gray matter in the aMCI group was negatively correlated with TUG.GMV of the bilateral frontal gyrus,right orbitofrontal gyrus,right occipital cleft,right supraoccipital gyrus,and left anterior central gyrus was positively correlated with walking speed.CONCLUSION GMV reduction in aMCI correlates with impaired cognition and motor function,emphasizing key roles for prefrontal,occipital,and central regions in gait disorders.
基金supported by Tianjin Key Medical Discipline(Specialty)Construction Project(grant number TJYXZDXK-004A).
文摘Background:Subcortical ischemic vascular dementia(SIVD)is a common subtype of vascular dementia.Currently,the bilateral common carotid artery stenosis(BCAS)mouse model is the most suitable SIVD rodent model.In this study,we investigated the functional and structural impairments in the hippocampus 1 month after BCAS.Methods:We used behavioral tests,laser speckle flowmetry,long-term potentiation,histochemical staining,molecular experiments,and voxel-based morphometry to evaluate the hippocampal impairments.Results:Behavioral studies revealed that BCAS mice exhibited worse performance.Laser speckle flowmetry detected an obvious decrease in cerebral blood flow.The synaptic plasticity of the perforant path-dentate gyrus pathway was inhibited.Decreased fractional anisotropy and increased mean diffusivity were detected in the hippocampus via diffusion tensor imaging data.A reduction in gray matter volume,which was most prominent in the hippocampus and its surrounding areas,was de-tected via voxel-based morphometry analysis.Impairments in cell morphology and myelin integrity were validated using histochemical staining and molecular biology techniques.In addition,the numbers of GFAP+astrocytes and Iba1+microglia in-creased in the hippocampus.Conclusions:Overall,our study demonstrates early functional and structural impair-ments in the hippocampus contributing to learning and memory deficits after 1 month of BCAS,indicating that the hippocampus is vulnerable to chronic cerebral ischemia.
基金Supported by National Natural Science Foundation of China(No.82160195,No.82460203)Science and Technology Project of Jiangxi Provincial Department of Education(No.GJJ200169)+1 种基金Science and Technology Project of Jiangxi Province Health Commission of Traditional Chinese Medicine(No.2020A0087)Science and Technology Project of Jiangxi Health Commission(No.202130210).
文摘AIM:To elucidate the neuropathological mechanisms underlying diabetic vitreous hemorrhage(DVH)and its correlation with clinical characteristics.METHODS:Twenty-one individuals with DVH(male/female 12/9;mean age 52.29±11.66y)were selected,alongside 21 appropriately matched controls with diabetes mellitus(DM).Voxel-based morphometry(VBM)techniques were employed to identify aberrant functional regions in the brain.Receiver operating characteristic(ROC)curves were utilized for classification based on the average VBM values of the two groups,and Pearson correlation analysis was conducted to assess the relationship between average VBM values in distinct brain regions and clinical manifestations.RESULTS:Relative to the DM controls,DVH patients exhibited reduced VBM values in the right superior temporal pole,the right superior temporal gyrus,the right medial orbital frontal gyrus,and the left superior frontal gyrus.Furthermore,ROC curve analysis of these four brain regions in DVH patients demonstrated a high degree of accuracy,as indicated by the area under the curve.The average VBM value in each of these regions exhibited a negative correlation with both the duration of DVH and the score on the Hospital Anxiety and Depression Scale(HADS).CONCLUSION:Pathological alterations in four distinct brain regions are observed in patients with DVH,potentially reflecting neuropathological changes associated with this condition.
基金Supported by National Natural Science Foundation of China Youth Fund:82004197Department of Science and Technology,National Administration of Traditional Chinese Medicine:GZY-KJS-2022-029The fifth batch of national research and training programs for clinical talents of traditional Chinese medicine,Project for new teachers of Beijing University of Chinese Medicine:2020-JYB-XJSJJ-045。
文摘Objective:Magnetic resonance imaging(MRI)studies have demonstrated anatomical and functional alterations of brain regions in patients with migraine,and the efficacy of acupuncture for migraine could regulate these abnormal alterations.However,its pathogenesis remains ambiguous,and inconsistent results have been reported.The purpose of this study was to explore abnormal structural and functional alterations in patients with migraine using voxel-based morphometry(VBM)analysis and a seed-based functional connectivity(FC)approach and to provide a basis for future research.Methods:The study recruited 34 patients with migraine and 38 healthy controls who underwent structural and resting-state functional magnetic resonance imaging(fMRI).VBM was evaluated across the whole brain,and group differences in the gray matter(GM)were compared.The significantly altered GM volumes considered as the seeding area were further calculated for the FC of the whole brain.The correlation between structural or functional changes of the brain and clinical features was also evaluated.Results:Patients with migraine manifested higher GM volumes in the left occipital lobe than healthy controls.Seed-based analyses demonstrated reduced FC between the left occipital lobe and right inferior frontal gyrus,extending to the anterior cingulate cortex(ACC)and right insula.Decreased FC in the left ACC was positively correlated with visual analog scale(VAS)and self-rating anxiety scale(SAS).
基金This study was supported by grants from the Foundation for Research Support of Rio de Janeiro(FAPERJ,grant No.E26/201.098/2022)the Coordination of Improvement of Higher Education Personnel(CAPES)the National Council for Scientific and Technological Development(CNPq,grant No.302808/2022-1).
文摘The objective of this study was to investigate whether treatment with Tribulus terrestris(Tt)has any impact on the testicular morphology and function in a rodent model.Twenty male rats were divided into a control group and a group receiving 100 mg kg^(-1) body weight of Tt supplementation.After 4o days of experiment,the animals were submitted to euthanasia;epididymal tail spermatozoa were collected;and spermatozoa concentration,motility,and viability were analyzed.In addition,testicles were collected and processed for histomorphometrical analyses.Data were compared using the Student's t-test and considered significant when P<O.05.Spermatozoa concentration,motility,and viability showed no difference between the groups.Further,testicular weight and volume,seminiferous tubule diameter,tunica propria surface density,seminiferous epithelium surface density,and intertubular compartment surface density were statistically similar between the groups.However,seminiferous epithelium height and tubular lumen surface density were augmented in animals treated with Tt.Treatment with Tt does not cause a major impact on testicular morphology,promoting only subtle modifications.No difference on spermatozoa parameters was observed.
基金Supported by the Guizhou Province Science and Technology Plan Project,No.ZK-2023-1952021 Health Commission of Guizhou Province Project,No.gzwkj2021-150.
文摘BACKGROUND Major depressive disorder(MDD)in adolescents and young adults contributes significantly to global morbidity,with inconsistent findings on brain structural changes from structural magnetic resonance imaging studies.Activation likeli-hood estimation(ALE)offers a method to synthesize these diverse findings and identify consistent brain anomalies.METHODS We performed a comprehensive literature search in PubMed,Web of Science,Embase,and Chinese National Knowledge Infrastructure databases for neuroi-maging studies on MDD among adolescents and young adults published up to November 19,2023.Two independent researchers performed the study selection,quality assessment,and data extraction.The ALE technique was employed to synthesize findings on localized brain function anomalies in MDD patients,which was supplemented by sensitivity analyses.RESULTS Twenty-two studies comprising fourteen diffusion tensor imaging(DTI)studies and eight voxel-based morphome-try(VBM)studies,and involving 451 MDD patients and 465 healthy controls(HCs)for DTI and 664 MDD patients and 946 HCs for VBM,were included.DTI-based ALE demonstrated significant reductions in fractional anisotropy(FA)values in the right caudate head,right insula,and right lentiform nucleus putamen in adolescents and young adults with MDD compared to HCs,with no regions exhibiting increased FA values.VBM-based ALE did not demonstrate significant alterations in gray matter volume.Sensitivity analyses highlighted consistent findings in the right caudate head(11 of 14 analyses),right insula(10 of 14 analyses),and right lentiform nucleus putamen(11 of 14 analyses).CONCLUSION Structural alterations in the right caudate head,right insula,and right lentiform nucleus putamen in young MDD patients may contribute to its recurrent nature,offering insights for targeted therapies.
文摘Context and Justification: Reconstructive spine surgery and the design of implants depend on disc and vertebral measurements, which vary according to racial groups and geographic areas. This variability underscores the importance of studying the morphometric characteristics specific to each population. Research Objective: The primary aim of this research was to determine the measurements of spinal components in the Congolese population in order to establish references suitable for local clinical practice. Materials and Methods: Congolese individuals, free from any spinal disorders, participated in a study on vertebral and disc morphology of the lumbar spine after providing informed consent. They underwent computed tomography examinations at medical imaging centers in Brazzaville. The parameters studied included: in axial sections, the transverse diameter (TDb) and sagittal diameter (SDb) of the vertebral bodies, the pedicular transverse diameter (TDp), and in sagittal reconstructions: the height of the vertebral bodies (Hb) and intervertebral discs (Hd). Results: The sample size consisted of 100 subjects (70 men and 30 women), with an average age of 24.47 ± 3.72 years (18 - 30 years). Cranio-caudally, the TDb, DSb, TDp, and Hd showed increasing values, while Hb values were decreasing. In L1, values for both sexes were: TDb = 39.3 ± 3 mm;DSb = 27.3 ± 2.9 mm;Hb = 26.6 ± 2.1 mm;TDp = 8.2 ± 1.8 mm;in L5: TDb = 50.3 ± 4 mm;DSb = 33.6 ± 2.7 mm;Hb = 25.7 ± 2.2 mm;TDp = 14.8 ± 2.1 mm. The Hd values were 8.1 ± 2.1 mm for L1 - L2 and 11.1 ± 2 mm for L5 - S1. Conclusion: Reconstructive spine surgery and the design of implants depend on disc and vertebral measurements, which vary according to racial groups and geographic areas. This variability underscores the importance of studying the morphometric characteristics specific to each population.
基金Supported by the grant of the National Natural Sciences Foundation of China(30470512)
文摘Objective To investigate cerebral structural signatures of the bulbar-and spinal-onset amyotrophic lateral sclerosis(ALS) using voxel-based morphometry on magnetic resonance imaging.Methods The MR structural images of the brain were obtained from 65 ALS patients(15 bulbar-onset, 50 spinalonset) and 65 normal controls(NC) on a 3.0 T MRI system. Gray matter(GM) volume changes were investigated by voxel-based morphometry, and the distribution of the brain regions with volume changes was compared between ALS and normal controls, as well as between bulbar-onset and spinal-onset ALS based on Neuromorphometrics atlas.Results On voxel-level the decreased volume of brain regions in ALS patients was located in the right precentral gyrus(r Prc Gy) and right middle frontal gyrus compared with that in NC. The bulbar-onset ALS presented extramotor cortex atrophy(fronto-temporal pattern), including left medial orbital gyrus, left inferior temporal gyrus and right middle temporal gyrus; the spinal-onset ALS suffered from motor cortex atrophy(r Prc Gy dominance) and extra-motor cortex atrophy(fronto-temporal and extra-fronto-temporal pattern) compared with NC. The spinal-onset ALS featured by GM volume loss of left postcentral gyrus and bulbar-onset ALS featured by GM volume loss of left middle temporal gyrus compared with each other. Conclusions The asymmetric GM atrophy of the motor cortex and extra-motor cortex represents the common MRI structural signatures of spinal-onset ALS, and sole extra-motor cortex atrophy represents the structural signatures of bulbar-onset ALS. The present study also demonstrated that the pattern of GM damage is likely to distribute wider in spinal-onset ALS than in bulbar-onset ALS.
基金the Ministry of Scientific Research and Education,Italy(MIUR).
文摘Chromosomal evolution is widely considered an important driver of speciation because it can promote the establishment of reproductive barriers.Karyotypic reorganization is also expected to affect the mea n phe no type,as well as its developme nt and patter ns of phenotypic in tegrati on,through processes such as variation in genetic linkage between quantitative trait loci or between regulatory regions and their targets.Here we explore the relationship between chromosomal evolution and phenotypic integration by analyzing a well-known house mouse parapatric contact zone between a highly derived Robertsonian(Rb)race(2n=22)and populations with standard karyotype(2n=40).Populations with hybrid karyotypes are scattered throughout the hybrid zone connecting the two parental races.Using mandible shape data and geometric morphometries,we test the hypothesis that patter ns of in tegration progressively diverge from the"normal"integration pattern observed in the standard race as they accumulate Rb fusions.We find that the main pattern of integration observed between the posterior and anterior part of the mandible can be largely attributed to allometry.We find no support for a gradual increase in divergence from normal patterns of integration as fusions accumulate.Surprisingly,however,we find that the derived Rb race(2n=22)has a distinct allometric trajectory compared with the standard race.Our results suggest that either individual fusions disproportionately affect patterns of integration or that there are mechanisms which"purge"extreme variants in hybrids(e.g.reduced fitness of hybrid shape).
基金the National Science Foundation Graduate Research Fellowship,UW BiologyBurke Museumthe National Science Foundation Postdoctoral Research Fellowship in Biology(DBI-1812126).
文摘Selective pressures favor morphologies that are adapted to distinct ecologies,resulting in trait partition!ng among ecomorphotypes.However,the effects of these selective pressures vary across taxa,especially because morphology is also influenced by factors such as phylogeny,body size,and functional trade-offs.In this study,we examine how these factors impact functional diversification in mammals.It has been proposed that trait partitioning among mammalian ecomorphotypes is less pronoun ced at small body sizes due to biomecha nical,energetic,and environ mental factors that favor a"generalist"body plan,whereas larger taxa exhibit more substantial functional adaptations.We title this the Diverge nee Hypothesis(DH)because it predicts greater morphological divergence among ecomorphotypes at larger body sizes.We test DH by using phylogenetic comparative methods to examine the postcranial skeletons of 129 species of taxonomically diverse,small-tomedium-sized(<15 kg)mammals,which we categorize as either"tree-dwellers"or"ground-dwellers."In some analyses,the morphologies of ground-dwellers and tree-dwellers suggest greater between-group differentiation at larger sizes,providing some evidence for DH.However,this trend is n either particularly strong nor supported by all an alyses.In stead,a more pronoun ced patter n emerges that is distinct from the predictions of DH:within-group phenotypic disparity increases with body size in both ground-dwellers and tree-dwellers,driven by morphological outliers among"medium'-sized mammals.Thus,evolutionary increases in body size are more closely linked to increases in within-locomotor-group disparity tha n to in creases in betwee n-group disparity.We discuss biomechanical and ecological factors that may drive these evolutionary patter ns,and we emphasize the significant evolutionary influences of ecology and body size on phenotypic diversity.
文摘Aim： To quantitatively study the histological changes of the testis and epididymis as a result of a drastic reduction of testosterone secretion. Methods： Fourteen adult Sprague-Dawley rats were injected intraperitoneally with ethane dimethane sulfonate （EDS, 75 mg/kg） and the same number of animals were injected with normal saline as a control. At days 7 and 12 （after treatment）, respectively, half of the animals from each group were killed. The testes and epididymides were removed and tissue blocks embedded in methacrylate resin. The cell number per testis was estimated using the stereological optical disector and some other parameters were obtained using other morphometric methods. Results： The EDS treatment resulted in an almost complete elimination of Leydig cells but had no effect on the numbers of Sertoli cells per testis. At day 7 after EDS treatment, many elongated spermatids were retained in the seminiferous epithelium and many round spermatids could be seen in the epididymal ducts. At day 12, a looser arrangement of spermatids and spermatocytes became evident, with apparent narrow empty spaces being formed between germ cells in an approximately radial direction towards the tubule lumen; the numbers （per testis） of non-type B spermatogonia and spermatocytes were similar to controls, whereas that of type B spermatogonia increased by 59%, and that of early round, elongating and late elongated spermatids decreased by 37%, 72% and 52%, respectively. Conclusion： The primary spermatogenic lesions following EDS administration were （i） spermiation failure and （ii） detachment of spermatids and spermatocytes associated with impairment in spermiogenesis and meiosis.
基金the Applied and Basic Scientific Research Fund of Yunnan Province,No.94C027Q.
文摘INTRODUCTION Hepatocellular carcinoma(HCC)is closely relatedwith hepatitis and cirrhosis.In order to investigatethe pathogenesis and early pathologic diagnosis ofHCC,HCC and related lesions were analyzedqualitively and quantitively by automatic imageanalysor and immunohistochemical assay.
基金This work was supported by the National Key Research and Development Program of China(2017 YFC0909201 and 2018YFC1314300)the National Natural Science Foundation of China(81571659,81971694,81971599,81771818,81425013,and 81871052)and the Tianjin Key Technology R&D Program(17ZXMFSY00090).
文摘A systematic characterization of the similarities and differences among different methods for detecting structural brain abnormalities in schizophrenia,such as voxel-based morphometry(VBM),tensor-based morphometry(TBM),and projection-based thickness(PBT),is important for understanding the brain pathology in schizophrenia and for developing effective biomarkers for a diagnosis of schizophrenia.However,such studies are still lacking.Here,we performed VBM,TBM,and PBT analyses on T1-weighted brain MR images acquired from 116 patients with schizophrenia and 116 healthy controls.We found that,although all methods detected wide-spread structural changes,different methods captured different information-only 10.35%of the grey matter changes in cortex were detected by all three methods,and VBM only detected 11.36%of the white matter changes detected by TBM.Further,pattern classification between patients and controls revealed that combining different measures improved the classification accuracy(81.9%),indicating that fusion of different structural measures serves as a better neuroimaging marker for the objective diagnosis of schizophrenia.
文摘Hepatic myelopathy is a complication seen in patients with chronic liver failure with physiologic or iatrogenic portosystemic shunting. The main symptom is progressive lower limb dyskinesia. The role of the brain motor control center in hepatic myelopathy is unknown. This study aimed to investigate the gray matter changes in patients with hepatic myelopathy secondary to transjugular intrahepatic portosystemic shunt and to examine their clinical relevance. This was a cross-sectional study. Twenty-three liver failure patients with hepatic myelopathy(hepatic myelopathy group), 23 liver failure patients without hepatic myelopathy(non-hepatic myelopathy group) after transjugular intrahepatic portosystemic shunt, and 23 demographically matched healthy volunteers were enrolled from March 2014 to November 2016 at Xijing Hospital, Air Force Military Medical University(Fourth Military Medical University), China. High-resolution magnetization-prepared rapid gradient-echo brain imaging was acquired. Group differences in regional gray matter were assessed using voxel-based morphometry analysis. The relationship between aberrant gray matter and motor characteristics was investigated. Results demonstrated that compared with the non-hepatic myelopathy group, gray matter volume abnormalities were asymmetric, with decreased volume in the left insula(P = 0.003), left thalamus(P = 0.029), left superior frontal gyrus(P = 0.006), and right middle cingulate cortex(P = 0.021), and increased volume in the right caudate nucleus(P = 0.017), corrected with open-source software. The volume of the right caudate nucleus in the hepatic myelopathy group negatively correlated with the lower limb clinical rating of the Fugl-Meyer Assessment(r = –0.53, P = 0.01). Compared with healthy controls, patients with and without hepatic myelopathy exhibited overall increased gray matter volume in both thalami, and decreased gray matter volume in both putamen, as well as in the globus pallidus, cerebellum, and vermis. The gray matter abnormalities we found predominantly involved motor-related regions, and may be associated with motor dysfunction. An enlarged right caudate nucleus might help to predict weak lower limb motor performance in patients with preclinical hepatic myelopathy after transjugular intrahepatic portosystemic shunt. This study was approved by the Ethics Committee of Xijing Hospital, Air Force Military Medical University(Fourth Military Medical University), China(approval No. 20140227-6) on February 27, 2014.
文摘After natural or artificial insemination, the spermatozoon starts a journey from the site of deposition to the place of fertilization. However, only a small subset of the spermatozoa deposited achieves their goal： to reach and fertilize the egg. Factors involved in controlling sperm transport and fertilization include the female reproductive tract environment, cell-cell interactions, gene expression, and phenotypic sperm traits. Some of the significant determinants of fertilization are known （i.e., motility or DNA status）, but many sperm traits are still indecipherable. One example is the influence of sperm dimensions and shape upon transport within the female genital tract towards the oocyte. Biophysical associations between sperm size and motility may influence the progression of spermatozoa through the female reproductive tract, but uncertainties remain concerning how sperm morphology influences the fertilization process, and whether only the sperm dimensions per se are involved. Moreover, such explanations do not allow the possibility that the female tract is capable of distinguishing fertile spermatozoa on the basis of their morphology, as seems to be the case with biochemical, molecular, and genetic properties. This review focuses on the influence of sperm size and shape in evolution and their putative role in sperm transport and selection within the uterus and the ability to fertilize the oocyte.
文摘The rain shadow regions requisite a comprehensive watershed development and management plan for sustainable water resources management. The Pambar River Basin （PRB） lies on the rain shadow region of the southern Western Ghats, India, where climate showed marked intra-basin variation. A morphometric analysis was done to evaluate the drainage characteristics of PRB using topographical maps and digital elevation data. PRB was divided into eighteen 4th order basins （SB1-SB18）, distributed along various climatic gradients. Lower order streams mostly dominate PRB and drainage pattern is a function of relief and structure. The terrain is highly dissected and prone to soil erosion during heavy storms and the elongated shape of PRB enables easier flood management. The influence of climate on drainage characteristics was evidently emphasized in basin morphometry. Four distinctively different classes were identified based on the morphometric similarities. The significance of morphometric analysis on the hydrological characterization is discussed and the relevance of the present study in water harvesting has been explicated.
基金supported by the National Natural Science Foundation of China (60831004 and 81270020)the CASIA Fund for Young Scientists with Lu-Jia-Xi award+2 种基金the Specific Healthcare Research Projects (13BJZ50)the Clinical Sciences Fund of the Chinese PLA General Hospital (2013FC-TSYS-1006)the Science Technological Innovation Nursery Fund of the Chinese PLA General Hospital (13KMM19), China
文摘Specific patterns of brain atrophy may be helpful in the diagnosis of Alzheimer＇s disease （AD）. In the present study, we set out to evaluate the utility of grey-matter volume in the classification of AD and amnestic mild cognitive impairment （aMCI） compared to normal control （NC）individuals. Voxel-based morphometric analyses were performed on structural MRIs from 35 AD patients, 27 aMCI patients, and 27 NC participants. A two-sample two-tailed t-test was computed between the NC and AD groups to create a map of abnormal grey matter in AD. The brain areas with significant differences were extracted as regions of interest （ROIs）, and the grey-matter volumes in the ROIs of the aMCI patients were included to evaluate the patterns of change across different disease severities. Next, correlation analyses between the grey-matter volumes in the ROIs and all clinical variables were performed in aMCI and AD patients to determine whether they varied with disease progression. The results revealed significantly decreased grey matter in the bilateral hippocampus/ parahippocampus, the bilateral superior/middle temporal gyri, and the right precuneus in AD patients.The grey-matter volumes with clinical variables were positively correlated Finally, we performed exploratory linear discriminative analyses to assess the classifying capacity of grey-matter volumes in the bilateral hippocampus and parahippocampus among AD, aMCI, and NC. Leave-one-out cross- validation analyses demonstrated that grey-matter volumes in hippocampus and parahippocampus accurately distinguished AD from NC. These findings indicate that grey-matter volumes are useful in the classification of AD.
