Objective High resolution structural MR imaging can reveal structural characteristics of cerebral cortex and provide an insight into normal brain development and neuropsychological diseases. The aim of this study was ...Objective High resolution structural MR imaging can reveal structural characteristics of cerebral cortex and provide an insight into normal brain development and neuropsychological diseases. The aim of this study was to compare cortical structural characteristics of normal human brain between 3T and 7T MRI systems using surface-based morphometry based on high resolution structural MR imaging.Methods Twelve healthy volunteers were scanned by both 3T with 3D T1-weighted fast spoiled gradient recalled echo (3D T1-FSPGR) sequence and 7T with 3D T1-weighted magnetization-prepared rapid gradient echo (3D T1-MPRAGE) sequence. MRI data were processed with FreeSurfer. The cortical thickness,white and gray matter surface area, convexity, and curvature from data of 3T and 7T were measured and compared by paired t-test.Results Measurements of mean cortical thickness, total white matter surface area and gray matter surface area of 3T were larger than those of 7T (left hemisphere: P=0.000, 0.006, 0.020 respectively; right hemisphere: P=0.000, 0.000, 0.000 respectively). Surface-based morphometry over the whole brain demonstrated both reduced and increased measurements of cortical thickness, white and gray surface area,convexity, and curvature at 7T compared to 3T.Conclusions Inconsistency of brain structural attribute between 3T and 7T was confirmed, and researchers should be cautious about data when using ultrahigh field MR system to investigate brain structural changes.展开更多
BACKGROUND Successful aging(SA)refers to the ability to maintain high levels of physical,cognitive,psychological,and social engagement in old age,with high cognitive function being the key to achieving SA.AIM To explo...BACKGROUND Successful aging(SA)refers to the ability to maintain high levels of physical,cognitive,psychological,and social engagement in old age,with high cognitive function being the key to achieving SA.AIM To explore the potential characteristics of the brain network and functional connectivity(FC)of SA.METHODS Twenty-six SA individuals and 47 usual aging individuals were recruited from community-dwelling elderly,which were taken the magnetic resonance imaging scan and the global cognitive function assessment by Mini Mental State Examination(MMSE).The resting state-functional magnetic resonance imaging data were preprocessed by DPABISurf,and the brain functional network was conducted by DPABINet.The support vector machine model was constructed with altered functional connectivities to evaluate the identification value of SA.RESULTS The results found that the 6 inter-network FCs of 5 brain networks were significantly altered and related to MMSE performance.The FC of the right orbital part of the middle frontal gyrus and right angular gyrus was mostly increased and positively related to MMSE score,and the FC of the right supramarginal gyrus and right temporal pole:Middle temporal gyrus was the only one decreased and negatively related to MMSE score.All 17 significantly altered FCs of SA were taken into the support vector machine model,and the area under the curve was 0.895.CONCLUSION The identification of key brain networks and FC of SA could help us better understand the brain mechanism and further explore neuroimaging biomarkers of SA.展开更多
Recent research has highlighted structural and functional abnormalities in the cerebral cortex of patients with premature ejaculation(PE).These anomalies could play a pivotal role in the physiological mechanisms under...Recent research has highlighted structural and functional abnormalities in the cerebral cortex of patients with premature ejaculation(PE).These anomalies could play a pivotal role in the physiological mechanisms underlying PE.This study leveraged functional magnetic resonance imaging(fMRI),a noninvasive technique,to explore these neural mechanisms.We conducted resting-state fMRI scans on 36 PE patients and 22 healthy controls(HC),and collected data on Premature Ejaculation Diagnostic Tool(PEDT)scores and intravaginal ejaculation latency time(IELT).Employing a surface-based regional homogeneity(ReHo)approach,we analyzed local neural synchronous spontaneous activity,diverging from previous studies that utilized a volume-based ReHo method.Areas with significant ReHo differences between PE and HC groups underwent surface-based functional connectivity(FC)analysis.Significant discrepancies in ReHo and FC across the cortical surface were observed in the PE cohort.Notably,PE patients exhibited decreased ReHo in the left triangular inferior frontal gyrus and enhanced ReHo in the right middle frontal gyrus.The latter showed heightened connectivity with the left lingual gyrus and the right orbital superior frontal gyrus.Furthermore,a correlation between ReHo and FC values with PEDT scores and IELT was found in the PE group.Our findings,derived from surface-based fMRI data,underscore specific brain regions linked to the neurobiological underpinnings of PE.展开更多
Pain is one of the manifestations of hip disorder and has been proven to lead to the remodeling of somatotopic map plasticity in the cortex.However,most studies are volume-based which may lead to inaccurate anatomical...Pain is one of the manifestations of hip disorder and has been proven to lead to the remodeling of somatotopic map plasticity in the cortex.However,most studies are volume-based which may lead to inaccurate anatomical positioning of functional data.The methods that work on the cortical surface may be more sensitive than those using the full brain volume and thus be more suitable for map plasticity study.In this prospective cross-sectional study performed in Yueyang Hospital of Integrated Traditional Chinese and Western Medicine,Shanghai University of Traditional Chinese Medicine,China,20 patients with osteonecrosis of the femoral head(12 males and 8 females,aged 56.80±13.60 years)and 20 healthy controls(9 males and 11 females,aged 54.56±10.23 years)were included in this study.Data of resting-state functional magnetic resonance imaging were collected.The results revealed that compared with healthy controls,compared with the healthy controls,patients with osteonecrosis of the femoral head(ONFH)showed significantly increased surface-based regional homogeneity(Re Ho)in areas distributed mainly in the left dorsolateral prefrontal cortex,frontal eye field,right frontal eye field,and the premotor cortex and decreased surface-based Re Ho in the right primary motor cortex and primary sensory cortex.Regions showing significant differences in surfacebased Re Ho values between the healthy controls and patients with ONFH were defined as the regions of interests.Seed-based functional connectivity was performed to investigate interregional functional synchronization.When the areas with decreased surface-based Re Ho in the frontal eye field and right premotor cortex were used as the regions of interest,compared with the healthy controls,the patients with ONFH displayed increased functional connectivity in the right middle frontal cortex and right inferior parietal cortex and decreased functional connectivity in the right precentral cortex and right middle occipital cortex.Compared with healthy controls,patients with ONFH showed significantly decreased cortical thickness in the para-insular area,posterior insular area,anterior superior temporal area,frontal eye field and supplementary motor cortex and reduced volume of subcortical gray matter nuclei in the right nucleus accumbens.These findings suggest that hip disorder patients showed cortical plasticity changes,mainly in sensorimotor-and pain-related regions.This study was approved by the Medical Ethics Committee of Yueyang Hospital of Integrated Traditional Chinese and Western Medicine,Shanghai University of Traditional Chinese Medicine(approval No.2018-041)on August 1,2018.展开更多
This paper describes a technique to estimate surface-based duct parameters by using a simple ray tracing/correlation method. The approach is novel in that it incorporates the Spearman rank-order correlation scheme bet...This paper describes a technique to estimate surface-based duct parameters by using a simple ray tracing/correlation method. The approach is novel in that it incorporates the Spearman rank-order correlation scheme between the observed surface clutter and the surface ray density for a given propagation path. The simulation results and the real data results both demonstrate the ability of this method to estimate surface-based duct parameters. Compared with the results obtained by a modified genetic algorithm combined with the parabolic wave equation, the results retrieved from the ray tracing/correlation scheme show a minor reduction in accuracy but a great improvement on computation time. Therefore the ray tracing/correlation method might be used as a precursor to more sophisticated and slower techniques, such as genetic algorithm and particle filters, by narrowing the parameter search space and providing a comprehensive and more efficient estimation algorithm.展开更多
The surface-based DNA computing is one of the methods of DNA computing which uses DNA strands immobilized on a solid surface. In this paper, we applied surface-based DNA computing for solving the dominating set proble...The surface-based DNA computing is one of the methods of DNA computing which uses DNA strands immobilized on a solid surface. In this paper, we applied surface-based DNA computing for solving the dominating set problem. At first step, surface-based DNA solution space was constructed by using appropriate DNA strands. Then, by application of a DNA parallel algorithm, dominating set problem was resolved in polynomial time.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
Morphometric changes in cortical thickness(CT),cortical surface area(CSA),and cortical volume(CV) can reflect pathological changes after acute mild traumatic brain injury(m TBI).Most previous studies focused on change...Morphometric changes in cortical thickness(CT),cortical surface area(CSA),and cortical volume(CV) can reflect pathological changes after acute mild traumatic brain injury(m TBI).Most previous studies focused on changes in CT,CSA,and CV in subacute or chronic m TBI,and few studies have examined changes in CT,CSA,and CV in acute m TBI.Furthermore,acute m TBI patients typically show transient cognitive impairment,and few studies have reported on the relationship between cerebral morphological changes and cognitive function in patients with m TBI.This prospective cohort study included 30 patients with acute m TBI(15 males,15 females,mean age 33.7 years) and 27 matched healthy controls(12 males,15 females,mean age 37.7 years) who were recruited from the Second Xiangya Hospital of Central South University between September and December 2019.High-resolution T1-weighted images were acquired within 7 days after the onset of m TBI.The results of analyses using Free Surfer software revealed significantly increased CSA and CV in the right lateral occipital gyrus of acutestage m TBI patients compared with healthy controls,but no significant changes in CT.The acute-stage m TBI patients also showed reduced executive function and processing speed indicated by a lower score in the Digital Symbol Substitution Test,and reduced cognitive ability indicated by a longer time to complete the Trail Making Test-B.Both increased CSA and CV in the right lateral occipital gyrus were negatively correlated with performance in the Trail Making Test part A.These findings suggest that cognitive deficits and cortical alterations in CSA and CV can be detected in the acute stage of m TBI,and that increased CSA and CV in the right lateral occipital gyrus may be a compensatory mechanism for cognitive dysfunction in acute-stage m TBI patients.This study was approved by the Ethics Committee of the Second Xiangya Hospital of Central South University,China(approval No.086) on February 9,2019.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
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
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
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
By utilizing the rabbit model, previous studies have found good evidence indicating that vasectomy-induced spermatogenic damage is pressure-mediated： the damage occurs when the occluded reproductive tract is unable t...By utilizing the rabbit model, previous studies have found good evidence indicating that vasectomy-induced spermatogenic damage is pressure-mediated： the damage occurs when the occluded reproductive tract is unable to accommodate additional spermatozoa produced by the testis. More studies with the more commonly used rat model have shown, however, controversial results on whether and why the damage occurs. In this study, 12 mature male Sprague-Dawley rats were subjected to unilateral vasectomy： double ligation （without severing） of the vas deferens exposed via a small inguinal incision; 37 days after the operation, the testes, epididymides, vasa deferentia （juxta-epididymal segments）, and sperm granulomas （at the vasectomy site） were removed to obtain methacrylate resin-embedded sections and morphometric studies carried out with light microscopy. Marked spermatogenic damage with spermatids and spermatocytes depleted in the seminiferous epithelium in 43% of the seminiferous tubule profiles was demonstrated in 5 of the 12 testes on the vasectomized side, and the damage was associated with smaller or absent sperm granulomas; in the other 7 testes with essentially normal spermatogenesis, there was an increase （by 111% on average） in the volume of the tubule lumen, associated with larger granulomas or granulomas containing more spermatozoa. There was an overall increase （by 66%） in the thickness of the rete testis in the 12 testes; the epididymis or vas deferens showed no distension. It seems therefore that the spermatogenic damage induced by vasectomy in rats is pressure-mediated as well, and that variation in the damage depends mainly on the postoperative development of the sperm granuloma.展开更多
Postcopulatory sexual selection through sperm competition may be an important evolutionary force affecting many reproductive traits, including sperm morphometrics. Environmental factors such as pollutants, pesticides,...Postcopulatory sexual selection through sperm competition may be an important evolutionary force affecting many reproductive traits, including sperm morphometrics. Environmental factors such as pollutants, pesticides, and climate change may affect different sperm traits, and thus reproduction, in sensitive bird species. Many sperm-handling processes used in assisted reproductive techniques may also affect the size of sperm cells. The accurately measured dimensions of sperm cell structures （especially the head） can thus be used as indicators of environmental influences, in improving our understanding of reproductive and evolutionary strategies, and for optimizing assisted reproductive techniques （e.g., sperm cryopreservation） for use with birds. Computer-assisted sperm morphometry analysis （CASA-Morph） provides an accurate and reliable method for assessing sperm morphometry, reducing the problem of subjectivity associated with human visual assessment. Computerized systems have been standardized for use with semen from different mammalian species. Avian spermatozoa, however, are filiform, limiting their analysis with such systems, which were developed to examine the approximately spherical heads of mammalian sperm cells. To help overcome this, the standardization of staining techniques to be used in compute^-assessed light microscopical methods is a priority. The present review discusses these points and describes the sperm morphometric characteristics of several wild and domestic bird species.展开更多
This work evaluates sperm head morphometric characteristics in adolescents from 12 to 18 years of age, and the effect of varicocele. Volunteers between 150 and 224 months of age （mean 191, n = 87）, who had reached o...This work evaluates sperm head morphometric characteristics in adolescents from 12 to 18 years of age, and the effect of varicocele. Volunteers between 150 and 224 months of age （mean 191, n = 87）, who had reached oigarche by 12 years old, were recruited in the area of Barranquilla, Colombia. Morphometric analysis of sperm heads was performed with principal component （PC） and discriminant analysis, Combining seminal fluid and sperm parameters provided five PCs： two related to sperm morphometry, one to sperm motility, and two to seminal fluid components. Discriminant analysis on the morphometric results of varicocele and nonvaricocele groups did not provide a useful classification matrix. Of the semen-related PCs, the most explanatory （40%） was related to sperm motility. Two PCs, including sperm head elongation and size, were sufficient to evaluate sperm morphometric characteristics. Most of the morphometric variables were correlated with age, with an increase in size and decrease in the elongation of the sperm head. For head size, the entire sperm population could be divided into two morphometric subpopulations, SP1 and SP2, which did not change during adolescence. In general, for varicocele individuals, SP1 had larger and more elongated sperm heads than SP2, which had smaller and more elongated heads than in nonvaricocele men. In summary, sperm head morphometry assessed by CASA-Morph and multivariate cluster analysis provides a better comprehension of the ejaculate structure and possibly sperm function. Morphometric analysis provides much more information than data obtained from conventional semen analysis.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
Spermatogenic damage may occur after vasectomy, and the damage is pressure mediated, occurring when the occluded reproductive tract is unable to accommodate additional sperm produced by the testis. This study aimed to...Spermatogenic damage may occur after vasectomy, and the damage is pressure mediated, occurring when the occluded reproductive tract is unable to accommodate additional sperm produced by the testis. This study aimed to determine the long-term effect of vasectomy on spermatogenesis in humans and clarify how the balance between sperm production in the testis and sperm storage in or removal from the tract might be maintained. During inguinal hernia repair, an open biopsy was performed to obtain testicular tissue blocks from 51 Chinese men （aged ≥ 50 years）, of whom 25 （control group） had not undergone vasectomy and 26 （vasectomized group） had undergone bilateral vasectomy 22-42 years before. Methacrylate resin-embedded testicular sections were made, and morphometric studies were performed using light microscopy. In addition, sizes of the testis and epididymis were estimated with ultrasonography. The testicular tissue blocks obtained from one control and seven vasectomized men consisted almost completely of connective tissue. In the other 43 men, significant differences were not found between the two groups in the testicular or epididymal size, qualitative histology or quantitative parameters including the mean diameter or volume fraction of the seminiferous tubules. In conclusion, sperm production and sperm storage/removal reached a static equilibrium after vasectomy, likely due to spermatogenic degeneration or less sperm production as a result of aging or due to vasectomy-induced testicular （interstitial） fibrosis. Thus, complications that might occur in association with overproduction of sperm and distension of the tract would disappear or be relieved with time.展开更多
基金Fund supported by National Natural Science Foundation of China (81171319), the Foundation for Medical and Health Sci & Tech Innovation Project of Sanya (2016YW37) and the Special Financial Grant from China Postdoctoral Science Foundation (2014T70960).
文摘Objective High resolution structural MR imaging can reveal structural characteristics of cerebral cortex and provide an insight into normal brain development and neuropsychological diseases. The aim of this study was to compare cortical structural characteristics of normal human brain between 3T and 7T MRI systems using surface-based morphometry based on high resolution structural MR imaging.Methods Twelve healthy volunteers were scanned by both 3T with 3D T1-weighted fast spoiled gradient recalled echo (3D T1-FSPGR) sequence and 7T with 3D T1-weighted magnetization-prepared rapid gradient echo (3D T1-MPRAGE) sequence. MRI data were processed with FreeSurfer. The cortical thickness,white and gray matter surface area, convexity, and curvature from data of 3T and 7T were measured and compared by paired t-test.Results Measurements of mean cortical thickness, total white matter surface area and gray matter surface area of 3T were larger than those of 7T (left hemisphere: P=0.000, 0.006, 0.020 respectively; right hemisphere: P=0.000, 0.000, 0.000 respectively). Surface-based morphometry over the whole brain demonstrated both reduced and increased measurements of cortical thickness, white and gray surface area,convexity, and curvature at 7T compared to 3T.Conclusions Inconsistency of brain structural attribute between 3T and 7T was confirmed, and researchers should be cautious about data when using ultrahigh field MR system to investigate brain structural changes.
基金Supported by the Wuxi Municipal Health Commission Major Project,No.Z202107。
文摘BACKGROUND Successful aging(SA)refers to the ability to maintain high levels of physical,cognitive,psychological,and social engagement in old age,with high cognitive function being the key to achieving SA.AIM To explore the potential characteristics of the brain network and functional connectivity(FC)of SA.METHODS Twenty-six SA individuals and 47 usual aging individuals were recruited from community-dwelling elderly,which were taken the magnetic resonance imaging scan and the global cognitive function assessment by Mini Mental State Examination(MMSE).The resting state-functional magnetic resonance imaging data were preprocessed by DPABISurf,and the brain functional network was conducted by DPABINet.The support vector machine model was constructed with altered functional connectivities to evaluate the identification value of SA.RESULTS The results found that the 6 inter-network FCs of 5 brain networks were significantly altered and related to MMSE performance.The FC of the right orbital part of the middle frontal gyrus and right angular gyrus was mostly increased and positively related to MMSE score,and the FC of the right supramarginal gyrus and right temporal pole:Middle temporal gyrus was the only one decreased and negatively related to MMSE score.All 17 significantly altered FCs of SA were taken into the support vector machine model,and the area under the curve was 0.895.CONCLUSION The identification of key brain networks and FC of SA could help us better understand the brain mechanism and further explore neuroimaging biomarkers of SA.
基金This work was financially supported by the National Natural Science Foundation of China(grant No.82001793)Social Development Project of Science and Technology in Jiangsu Province(grant No.BE2019606)。
文摘Recent research has highlighted structural and functional abnormalities in the cerebral cortex of patients with premature ejaculation(PE).These anomalies could play a pivotal role in the physiological mechanisms underlying PE.This study leveraged functional magnetic resonance imaging(fMRI),a noninvasive technique,to explore these neural mechanisms.We conducted resting-state fMRI scans on 36 PE patients and 22 healthy controls(HC),and collected data on Premature Ejaculation Diagnostic Tool(PEDT)scores and intravaginal ejaculation latency time(IELT).Employing a surface-based regional homogeneity(ReHo)approach,we analyzed local neural synchronous spontaneous activity,diverging from previous studies that utilized a volume-based ReHo method.Areas with significant ReHo differences between PE and HC groups underwent surface-based functional connectivity(FC)analysis.Significant discrepancies in ReHo and FC across the cortical surface were observed in the PE cohort.Notably,PE patients exhibited decreased ReHo in the left triangular inferior frontal gyrus and enhanced ReHo in the right middle frontal gyrus.The latter showed heightened connectivity with the left lingual gyrus and the right orbital superior frontal gyrus.Furthermore,a correlation between ReHo and FC values with PEDT scores and IELT was found in the PE group.Our findings,derived from surface-based fMRI data,underscore specific brain regions linked to the neurobiological underpinnings of PE.
基金supported by National Key R&D Program of China,No.2018YFC2001600(to JGX)the National Natural Science Foundation of China,Nos.81802249(to XYH),81871836(to MXZ)+4 种基金a grant from Shanghai Science and Technology Committee of China,Nos.18511108300(to JGX),18441903903900(to XYH),18441903800(to MXZ)Three-Year Action Plan for Traditional Chinese Medicine Development from Shanghai Municipal Health Commission of China,No.ZY(2018-2020)-ZWB-1001-CPJS49(to BL)ZY(2018-2020)-RCPY-3007(to JM)Traditional Chinese Medicine Diagnosis and Treatment Technology Improvement Project from Shanghai Municipal Commission of Health and Family Planning of China,No.Zyjx-2017006(to BL)Special Project of Postgraduate Innovation Training of China,No.A1-GY20-204-0107(to JM)。
文摘Pain is one of the manifestations of hip disorder and has been proven to lead to the remodeling of somatotopic map plasticity in the cortex.However,most studies are volume-based which may lead to inaccurate anatomical positioning of functional data.The methods that work on the cortical surface may be more sensitive than those using the full brain volume and thus be more suitable for map plasticity study.In this prospective cross-sectional study performed in Yueyang Hospital of Integrated Traditional Chinese and Western Medicine,Shanghai University of Traditional Chinese Medicine,China,20 patients with osteonecrosis of the femoral head(12 males and 8 females,aged 56.80±13.60 years)and 20 healthy controls(9 males and 11 females,aged 54.56±10.23 years)were included in this study.Data of resting-state functional magnetic resonance imaging were collected.The results revealed that compared with healthy controls,compared with the healthy controls,patients with osteonecrosis of the femoral head(ONFH)showed significantly increased surface-based regional homogeneity(Re Ho)in areas distributed mainly in the left dorsolateral prefrontal cortex,frontal eye field,right frontal eye field,and the premotor cortex and decreased surface-based Re Ho in the right primary motor cortex and primary sensory cortex.Regions showing significant differences in surfacebased Re Ho values between the healthy controls and patients with ONFH were defined as the regions of interests.Seed-based functional connectivity was performed to investigate interregional functional synchronization.When the areas with decreased surface-based Re Ho in the frontal eye field and right premotor cortex were used as the regions of interest,compared with the healthy controls,the patients with ONFH displayed increased functional connectivity in the right middle frontal cortex and right inferior parietal cortex and decreased functional connectivity in the right precentral cortex and right middle occipital cortex.Compared with healthy controls,patients with ONFH showed significantly decreased cortical thickness in the para-insular area,posterior insular area,anterior superior temporal area,frontal eye field and supplementary motor cortex and reduced volume of subcortical gray matter nuclei in the right nucleus accumbens.These findings suggest that hip disorder patients showed cortical plasticity changes,mainly in sensorimotor-and pain-related regions.This study was approved by the Medical Ethics Committee of Yueyang Hospital of Integrated Traditional Chinese and Western Medicine,Shanghai University of Traditional Chinese Medicine(approval No.2018-041)on August 1,2018.
基金Project supported by the National Natural Science Foundation of China (Grant No. 40775025)
文摘This paper describes a technique to estimate surface-based duct parameters by using a simple ray tracing/correlation method. The approach is novel in that it incorporates the Spearman rank-order correlation scheme between the observed surface clutter and the surface ray density for a given propagation path. The simulation results and the real data results both demonstrate the ability of this method to estimate surface-based duct parameters. Compared with the results obtained by a modified genetic algorithm combined with the parabolic wave equation, the results retrieved from the ray tracing/correlation scheme show a minor reduction in accuracy but a great improvement on computation time. Therefore the ray tracing/correlation method might be used as a precursor to more sophisticated and slower techniques, such as genetic algorithm and particle filters, by narrowing the parameter search space and providing a comprehensive and more efficient estimation algorithm.
文摘The surface-based DNA computing is one of the methods of DNA computing which uses DNA strands immobilized on a solid surface. In this paper, we applied surface-based DNA computing for solving the dominating set problem. At first step, surface-based DNA solution space was constructed by using appropriate DNA strands. Then, by application of a DNA parallel algorithm, dominating set problem was resolved in polynomial time.
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 the National Natural Science Foundation of China,No.81671671 (to JL)。
文摘Morphometric changes in cortical thickness(CT),cortical surface area(CSA),and cortical volume(CV) can reflect pathological changes after acute mild traumatic brain injury(m TBI).Most previous studies focused on changes in CT,CSA,and CV in subacute or chronic m TBI,and few studies have examined changes in CT,CSA,and CV in acute m TBI.Furthermore,acute m TBI patients typically show transient cognitive impairment,and few studies have reported on the relationship between cerebral morphological changes and cognitive function in patients with m TBI.This prospective cohort study included 30 patients with acute m TBI(15 males,15 females,mean age 33.7 years) and 27 matched healthy controls(12 males,15 females,mean age 37.7 years) who were recruited from the Second Xiangya Hospital of Central South University between September and December 2019.High-resolution T1-weighted images were acquired within 7 days after the onset of m TBI.The results of analyses using Free Surfer software revealed significantly increased CSA and CV in the right lateral occipital gyrus of acutestage m TBI patients compared with healthy controls,but no significant changes in CT.The acute-stage m TBI patients also showed reduced executive function and processing speed indicated by a lower score in the Digital Symbol Substitution Test,and reduced cognitive ability indicated by a longer time to complete the Trail Making Test-B.Both increased CSA and CV in the right lateral occipital gyrus were negatively correlated with performance in the Trail Making Test part A.These findings suggest that cognitive deficits and cortical alterations in CSA and CV can be detected in the acute stage of m TBI,and that increased CSA and CV in the right lateral occipital gyrus may be a compensatory mechanism for cognitive dysfunction in acute-stage m TBI patients.This study was approved by the Ethics Committee of the Second Xiangya Hospital of Central South University,China(approval No.086) on February 9,2019.
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 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.
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.
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.
文摘By utilizing the rabbit model, previous studies have found good evidence indicating that vasectomy-induced spermatogenic damage is pressure-mediated： the damage occurs when the occluded reproductive tract is unable to accommodate additional spermatozoa produced by the testis. More studies with the more commonly used rat model have shown, however, controversial results on whether and why the damage occurs. In this study, 12 mature male Sprague-Dawley rats were subjected to unilateral vasectomy： double ligation （without severing） of the vas deferens exposed via a small inguinal incision; 37 days after the operation, the testes, epididymides, vasa deferentia （juxta-epididymal segments）, and sperm granulomas （at the vasectomy site） were removed to obtain methacrylate resin-embedded sections and morphometric studies carried out with light microscopy. Marked spermatogenic damage with spermatids and spermatocytes depleted in the seminiferous epithelium in 43% of the seminiferous tubule profiles was demonstrated in 5 of the 12 testes on the vasectomized side, and the damage was associated with smaller or absent sperm granulomas; in the other 7 testes with essentially normal spermatogenesis, there was an increase （by 111% on average） in the volume of the tubule lumen, associated with larger granulomas or granulomas containing more spermatozoa. There was an overall increase （by 66%） in the thickness of the rete testis in the 12 testes; the epididymis or vas deferens showed no distension. It seems therefore that the spermatogenic damage induced by vasectomy in rats is pressure-mediated as well, and that variation in the damage depends mainly on the postoperative development of the sperm granuloma.
文摘Postcopulatory sexual selection through sperm competition may be an important evolutionary force affecting many reproductive traits, including sperm morphometrics. Environmental factors such as pollutants, pesticides, and climate change may affect different sperm traits, and thus reproduction, in sensitive bird species. Many sperm-handling processes used in assisted reproductive techniques may also affect the size of sperm cells. The accurately measured dimensions of sperm cell structures （especially the head） can thus be used as indicators of environmental influences, in improving our understanding of reproductive and evolutionary strategies, and for optimizing assisted reproductive techniques （e.g., sperm cryopreservation） for use with birds. Computer-assisted sperm morphometry analysis （CASA-Morph） provides an accurate and reliable method for assessing sperm morphometry, reducing the problem of subjectivity associated with human visual assessment. Computerized systems have been standardized for use with semen from different mammalian species. Avian spermatozoa, however, are filiform, limiting their analysis with such systems, which were developed to examine the approximately spherical heads of mammalian sperm cells. To help overcome this, the standardization of staining techniques to be used in compute^-assessed light microscopical methods is a priority. The present review discusses these points and describes the sperm morphometric characteristics of several wild and domestic bird species.
文摘This work evaluates sperm head morphometric characteristics in adolescents from 12 to 18 years of age, and the effect of varicocele. Volunteers between 150 and 224 months of age （mean 191, n = 87）, who had reached oigarche by 12 years old, were recruited in the area of Barranquilla, Colombia. Morphometric analysis of sperm heads was performed with principal component （PC） and discriminant analysis, Combining seminal fluid and sperm parameters provided five PCs： two related to sperm morphometry, one to sperm motility, and two to seminal fluid components. Discriminant analysis on the morphometric results of varicocele and nonvaricocele groups did not provide a useful classification matrix. Of the semen-related PCs, the most explanatory （40%） was related to sperm motility. Two PCs, including sperm head elongation and size, were sufficient to evaluate sperm morphometric characteristics. Most of the morphometric variables were correlated with age, with an increase in size and decrease in the elongation of the sperm head. For head size, the entire sperm population could be divided into two morphometric subpopulations, SP1 and SP2, which did not change during adolescence. In general, for varicocele individuals, SP1 had larger and more elongated sperm heads than SP2, which had smaller and more elongated heads than in nonvaricocele men. In summary, sperm head morphometry assessed by CASA-Morph and multivariate cluster analysis provides a better comprehension of the ejaculate structure and possibly sperm function. Morphometric analysis provides much more information than data obtained from conventional semen analysis.
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Spermatogenic damage may occur after vasectomy, and the damage is pressure mediated, occurring when the occluded reproductive tract is unable to accommodate additional sperm produced by the testis. This study aimed to determine the long-term effect of vasectomy on spermatogenesis in humans and clarify how the balance between sperm production in the testis and sperm storage in or removal from the tract might be maintained. During inguinal hernia repair, an open biopsy was performed to obtain testicular tissue blocks from 51 Chinese men （aged ≥ 50 years）, of whom 25 （control group） had not undergone vasectomy and 26 （vasectomized group） had undergone bilateral vasectomy 22-42 years before. Methacrylate resin-embedded testicular sections were made, and morphometric studies were performed using light microscopy. In addition, sizes of the testis and epididymis were estimated with ultrasonography. The testicular tissue blocks obtained from one control and seven vasectomized men consisted almost completely of connective tissue. In the other 43 men, significant differences were not found between the two groups in the testicular or epididymal size, qualitative histology or quantitative parameters including the mean diameter or volume fraction of the seminiferous tubules. In conclusion, sperm production and sperm storage/removal reached a static equilibrium after vasectomy, likely due to spermatogenic degeneration or less sperm production as a result of aging or due to vasectomy-induced testicular （interstitial） fibrosis. Thus, complications that might occur in association with overproduction of sperm and distension of the tract would disappear or be relieved with time.
