BACKGROUND A stroke is a significant brain event that impinges on individual motor or cognitive functions.In the lacunar stroke subtype of ischemic stroke,which results from blocked blood flow in certain brain areas,c...BACKGROUND A stroke is a significant brain event that impinges on individual motor or cognitive functions.In the lacunar stroke subtype of ischemic stroke,which results from blocked blood flow in certain brain areas,cases of dysarthria due to impaired blood flow are not uncommon.However,limited literature and research on the relevant pathophysiology and neural pathways exist.CASE SUMMARY We focus on a 60-year-old female with subacute stroke presenting symptoms including tongue deviation to the right,speech difficulty,choking on water,and biting the oral mucosa.She did not exhibit abnormalities in limb movement or sensation except for numbness in the tongue.We use single-photon emission computed tomography to reveal reduced blood flow in the left parietal lobe and bilateral temporal lobes.This report presents an atypical case of dysarthria,who exhibits abnormal articulation along with abnormal sensation and numbness in the tongue,prompting further investigation into the association between lacunar stroke subtypes,altered blood perfusion in affected brain regions,and neurological clinical status.CONCLUSION Dysarthria-plus syndrome in lacunar stroke isn’t solely related to motor function but also affects sensory function such as oral numbness.展开更多
Normalized Difference Vegetation Index （NDVI） is a very useful feature for differentiating vegetation and non-vegetation in remote sensed imagery. In the light of the function of NDVI and the spatial patterns of the...Normalized Difference Vegetation Index （NDVI） is a very useful feature for differentiating vegetation and non-vegetation in remote sensed imagery. In the light of the function of NDVI and the spatial patterns of the vegetation landscapes, we proposed the lacunarity texture derived from NDVI to characterize the spatial patterns of vegetation landscapes concerning the ＂gappiness＂ or ＂emptiness＂ characteristics. The NDVI-based lacunarity texture was incorporated into object-oriented classification for improving the identification of vegetation categories, especially Torreya which was the targeted tree species in the present research. A three-level hierarchical network of image objects was defined and the proposed texture was integrated as potential sources of information in the rules base. A knowledge base of rules created by classifier C5.0 indicated that the texture could potentially be applied in object-oriented classification. It was found that the addition of such texture improved the identification of every vegetation category. The results demonstrated that the texture could characterize the spatial patterns of vegetation structures, which could be a promising approach for vegetation identification.展开更多
BACKGROUND The main pathological factor of cerebral infarction is atherosclerosis,which is the pathological process of chronic inflammatory diseases such as vascular smooth muscle hyperplasia,inflammatory cell infiltr...BACKGROUND The main pathological factor of cerebral infarction is atherosclerosis,which is the pathological process of chronic inflammatory diseases such as vascular smooth muscle hyperplasia,inflammatory cell infiltration,extracellular matrix increase,and thrombosis.At present,the focus of clinical treatment is anti-platelet aggregation and improving blood status,and current research is limited to improving symptoms only.AIM To observe the effect of sodium ozagrel and atorvastatin on type 2 diabetes patients with lacunar cerebral infarction.METHODS Eighty-two patients with type 2 diabetes and lacunar cerebral infarction admitted to our hospital from January 2018 to February 2020 were equally categorized into two groups according to their treatment method.The control group was administered atorvastatin,and the observation group was administered sodium ozagrel combined with atorvastatin.The National Institutes of Health stroke scale(NIHSS)score,activities of daily living(ADL)score,blood glucose,lipid levels,inflammatory factors,high-mobility group box 1(HMGB1)levels,paraoxonase-1(PON-1)levels,erythrocyte sedimentation rate(ESR),and macrophage migration inhibitory factor(MIF)levels were recorded before and after treatment.The total effective rate and adverse reaction rate of the two groups were analyzed.RESULTS The total effective rate of the observation group(94.00%)was significantly higher than that of the control group(80.00%)(χ2=3.998;P=0.046).The blood glucose indexes,total cholesterol levels,triglyceride levels,low-density lipoprotein cholesterol levels,high-sensitivity C-reactive protein levels,interleukin-1βlevels,tumor necrosis factor-αlevels,HMGB1 Levels,ESR,MIF levels,platelet aggregation rates,and plasma viscosity of the two groups decreased after treatment;however,high-density lipoprotein cholesterol and PON-1 Levels increased after treatment.After treatment,the blood glucose indexes;blood lipid indexes;inflammatory factors;HMGB1,PON-1,and MIF levels;ESR;platelet aggregation rate;and plasma viscosity of the observation group were better than those of the control group(P<0.05).After treatment,all patients in the observation group had higher ADL scores and lower NIHSS scores than those in the control group(P<0.05).CONCLUSION Sodium ozagrel with atorvastatin can reduce inflammatory reactions;regulate ESR and HMGB1,PON-1,and MIF levels;control blood glucose and lipid indexes;and alleviate nerve injury without increasing adverse effects of atorvastatin alone.展开更多
This study semi-quantitatively analyzed the effects of leukoaraiosis.Patients with moderate or severe lacunar infarction were found to exhibit low scores on the Montreal Cognitive Assessment Scale （F=12.02,P=0.000）,...This study semi-quantitatively analyzed the effects of leukoaraiosis.Patients with moderate or severe lacunar infarction were found to exhibit low scores on the Montreal Cognitive Assessment Scale （F=12.02,P=0.000）,and prolonged P300 Cz2.0 latency （F=16.04,P=0.000）.Correlation analysis revealed that the occurrence of leukoaraiosis was negatively correlated with Montreal Cognitive Assessment scores （r=-0.416,P=0.000）,and positively correlated with P300 Cz2.0 latency （r=0.538,P=0.000）.These findings indicate that leukoaraiosis aggravates cognitive impairment in patients with lacunar infarction,such that more severe leukoaraiosis is associated with more severe cognitive decline.展开更多
Osteoporosis represents one major health condition for our growing elderly population. It accounts for severe morbidity and increased mortality in postmenopausal women and it is becoming an emerging health concern eve...Osteoporosis represents one major health condition for our growing elderly population. It accounts for severe morbidity and increased mortality in postmenopausal women and it is becoming an emerging health concern even in aging men. Screening of the population at risk for bone degeneration and treatment assessment of osteoporotic patients to prevent bone fragility fractures represent useful tools to improve quality of life in the elderly and to lighten the related socio-economic impact. Bone mineral density(BMD) estimate by means of dual-energy X-ray absorptiometry is normally used in clinical practice for osteoporosis diagnosis. Nevertheless, BMD alone does not represent a good predictor of fracture risk. From a clinical point of view, bone microarchitecture seems to be an intriguing aspect to characterize bone alteration patterns in aging and pathology. The widening into clinical practice of medical imaging techniques and the impressive advances in information technologies together with enhanced capacity of power calculation have promoted proliferation of new methods to assess changes of trabecular bone architecture(TBA) during aging and osteoporosis. Magnetic resonance imaging(MRI) has recently arisen as a useful tool to measure bone structure in vivo. In particular, high-resolution MRI techniques have introduced new perspectives for TBA characterization by non-invasive non-ionizing methods. However, texture analysis methods have not found favor with clinicians as they produce quite a few parameters whose interpretation is difficult. The introduction in biomedical field of paradigms, such as theory of complexity, chaos, and fractals, suggests new approaches and provides innovative tools to develop computerized methods that, by producing a limited number of parameters sensitive to pathology onset and progression, would speed up their application into clinical practice. Complexity of living beings and fractality of several physio-anatomic structures suggest fractal analysis as a promising approach to quantify morphofunctional changes in both aging and pathology. In this particular context, fractal lacunarity seems to be the proper tool to characterize TBA texture as it is able to describe both discontinuity of bone network and sizes of bone marrow spaces, whose changes are an index of bone fracture risk. In this paper, an original method of MRI texture analysis, based on TBA fractal lacunarity is described and discussed in the light of new perspectives for early diagnosis of osteoporotic fractures.展开更多
The spatial structure characteristics of landform are the foundation of geomorphologic classification and recognition.This paper proposed a new method on quantifying spatial structure characteristics of terrain surfac...The spatial structure characteristics of landform are the foundation of geomorphologic classification and recognition.This paper proposed a new method on quantifying spatial structure characteristics of terrain surface based on improved 3D Lacunarity model.Lacunarity curve and its numerical integration are used in this model to improve traditional classification result that different morphological types may share the close value of indexes based on global statistical analysis.Experiments at four test areas with different landform types show that improved 3D Lacunarity model can effectively distinguish different morphological types per texture analysis.Higher sensitivity in distinguishing the tiny differences of texture characteristics of terrain surface shows that the quantification method by 3D Lacu-narity model and its numerical integration presented in this paper could contribute to improving the accuracy of land-form classifications and relative studies.展开更多
The genes for 5-1ipoxygenase activating protein （ALOX5AP） and phosphodiesterase 4D （PDE4D） have been demonstrated as susceptibility genes for lacunar in the Icelandic and Pakistani populations, but little is known...The genes for 5-1ipoxygenase activating protein （ALOX5AP） and phosphodiesterase 4D （PDE4D） have been demonstrated as susceptibility genes for lacunar in the Icelandic and Pakistani populations, but little is known about the role of these genes in Chinese populations. The present study utilized polymerase chain reaction and ligase detection reaction to detect single nucleotide polymorphisms （SNPs） in 280 consecutive stroke patients and 258 unrelated population-based controls from Nanjing, Jiangsu Province, China. The allele frequency, genotypes, and haplotypes of the two SNPs （rs456009 and rs966221） in PDE4D were similar between the two groups. However, A allele frequency of rs4073259 （A/G） and rs4769055 （A/C） in the ALOX5AP gene exhibited differences in two groups, and especially the haplotype of the SNP was significantly different between the two groups. Results suggested that the ALOX5AP gene might be involved in lacunar infarct, while PDE4D gene was not a risk factor for lacunar infarct in individuals from Jiangsu Province, China.展开更多
Objective To study the relationships between cognitive impairment in patients with lacunar infarcts and quantitative CT measures and to determine the independent correlative factors of cognitive impairment.Methods Neu...Objective To study the relationships between cognitive impairment in patients with lacunar infarcts and quantitative CT measures and to determine the independent correlative factors of cognitive impairment.Methods Neuropsychological examination was conducted for 128 patients with acute lacunar infarct.Number,location,and volume of infarcts,cerebral atrophy index and severity of white matter lesions(WMLs) were measured and recorded.Results The number of lacunar infarcts in cognitive impairment (CI) group was significantly larger than that in cognitive normal(CN) group.Mean width of sulcus and sylvian fissure,index of frontal horn and ventricular-brain ratio(VBR) were significantly different in both groups.There were more patients with 3 grades or 4 grades WMLs in CI group(62%) than those in CN group(22%).The total volume of lacunar infarcts showed no statistically significant difference.Logistic regression analysis indicated that the number of lacunar infarcts in frontal subcortex and thalamus,the volume of infarcts in anterior periventricular white matter,width of cerebral sulcus and sylvian fissure were correlated with cognitive impairment respectively.Additionally,age and education were correlative factors of cognitive impairment in patients with lacunar infarct.Conclusion Correlative factors of cognitive impairment in patients with lacunar infarct are not merely one feature,but a combination of infarct features(number,location,and volume),cortical atrophy and host factors(age and education).展开更多
AIM:To investigate the correlation of ischemic ophthalmopathy(IO)with lacunar infarction(LI),an ischemic lesions in the cerebrovascular system.METHODS:Totally 204 cases of IO without any nervous system symptom and pre...AIM:To investigate the correlation of ischemic ophthalmopathy(IO)with lacunar infarction(LI),an ischemic lesions in the cerebrovascular system.METHODS:Totally 204 cases of IO without any nervous system symptom and previously diagnosed LI served as the observational group.All 204 cases without IO,nervous system symptoms and previous LI served as the control group.Age and sex between the two groups matched well.LI was diagnosed by magnetic resonance imaging(MRI)and the results of the two groups were statistically analyzed and compared.RESULTS:IO included 174 eyes of 156 patients with non-arteritis anterior ischemic optic neuropathy(NAION),42 eyes of 36 patients with central retinal artery occlusion(CRAO)or branch retinal artery occlusion(BRAO)and 12 eyes of 12 patients with ocular ischemia syndrome(OIS).The detection rate of LI(72.54%)in IO group was obviously higher than that(15.68%)in the control group(P<0.001).IO was positively correlated with LI(r=0.573,P<0.05).In addition,most infarction sites located in the basal ganglia(67.57%),which were not the vital areas of cerebrum and not easy to be found due to their small size.The majority of those first visited IO patients(72.54%)without nervous system symptom and previously diagnosed LI had already suffered from LI.CONCLUSION:According to our studies,there is a positive correlation between IO and LI.IO can be used as an important predictor for the present of LI,especially obvious signs of the patient.展开更多
Objective We conducted a study using MRI and ambulatory blood pressure monitoring(ABPM) to determine whether an in-apporpriately low nocturnal blood pressure, or an excess fall in nocturnal blood pressure, might be re...Objective We conducted a study using MRI and ambulatory blood pressure monitoring(ABPM) to determine whether an in-apporpriately low nocturnal blood pressure, or an excess fall in nocturnal blood pressure, might be responsible for lacunar infarct. Method ABPM and Casul blood pressure(CBP) were examined in 35 hypertentives with lacunar infarct(LI)and 33 hypertentives without lacunar infarct as control group. Results There is no significant difference of CBP between two groups. But the mean nighttime systolic blood pressure (nSBP) and diastolic blood pressure (nDBP) in patients with lacunar infarct were significantly smaller than in patients without lacunar infarct. The ratio of nSBP/dSBP and nDBP/dDBP in SI were smaller than in control group respectively. Conclusions The results indicate that an inap-propriately low nocturnal blood pressure, or an excessive fall in nocturnal blood pressure, is associated with lacunar infarct. It is necessary not only to control high blood pressure but also to pay attention to circadian changes of blood pressure during the course of anti-hypertensive treatment.展开更多
A 59 year old white male presented with a clinical picture typical of lacunar stroke. However, a thorough diagnostic work up showed that the most probable mechanism of stroke was paradoxical brain embolism through a p...A 59 year old white male presented with a clinical picture typical of lacunar stroke. However, a thorough diagnostic work up showed that the most probable mechanism of stroke was paradoxical brain embolism through a patent foramen ovale. The clinical-neuroradiological mismatch that ultimately lead to the correct interpretation is discussed.展开更多
Pure motor stroke(PMS), also known as pure motor hemiparesis, is the most common of any lacunar form(between one half and two thirds of cases, depending on the series). In an acute stroke registry, 733 patients presen...Pure motor stroke(PMS), also known as pure motor hemiparesis, is the most common of any lacunar form(between one half and two thirds of cases, depending on the series). In an acute stroke registry, 733 patients presented a lacunar infarct and PMS accounted for 12.7%(n = 342) of all first-ever stroke patients and for 48% of all lacunar syndromes. The posterior limb of the internal capsule, corona radiata, and pons are the most frequent brain topographies. Infarcts in the mesencephalus or medullary pyramid have been exceptionally reported. This present update is focused on the clinical evidence and mechanisms underlying the relationship between PMS and different stroke etiologies.展开更多
Objective: To investigate the diagnostic effects of CT and magnetic resonance imaging (MRI) in patients with lacunar infarction. Methods: Thirty patients with early lacunar infarction in our hospital were diagnosed by...Objective: To investigate the diagnostic effects of CT and magnetic resonance imaging (MRI) in patients with lacunar infarction. Methods: Thirty patients with early lacunar infarction in our hospital were diagnosed by ct and 30 patients were diagnosed by magnetic resonance imaging according to the examination time, the average diameter of infarct focus and examination cost. Vascular image quality (siphon segment score of internal carotid artery, petrous segment score of artery, posterior communicating artery score and basilar artery score), and the lesion detection rates of the two inspection methods were compared;Results The detection effect of MRI was superior to that of ct (P < 0.05). Conclusion: patients with lacunar infarction by magnetic resonance imaging technology and ct two ways of diagnosis, can get good diagnosis effect, but the magnetic resonance imaging technology to detect the infarct diameter is larger, the diagnosis effect is better, the detection time is shorter, however, the examination cost is more, can according to the needs of patients in clinical reasonable choice of examination methods.展开更多
Objective:To investigate,in basal ganglia,the factors associated with early neurological deterioration(END)of isolated acute lacunar infarction.Methods:167 patients,in the retrospective group,with isolated acute lacun...Objective:To investigate,in basal ganglia,the factors associated with early neurological deterioration(END)of isolated acute lacunar infarction.Methods:167 patients,in the retrospective group,with isolated acute lacunar infarction in basal ganglia,were defined by magnetic resonance imaging(MRI).The National Institutes of Health Stroke Scale(NIHSS)defined early neurological deterioration as increases of≥2 within 72 hours following admission.Baseline variables predicting END were investigated with multivariate logistic regression analysis.Results:In the study,END occurred in 42(25.15%)patients.Lesions located in posterior limb of internal capsule were independent risk factors for END(P<0.01).Associated with END were the age of onset,history of cerebral infarction,history of diabetes,systolic blood pressure at admission and lesions of cerebral white matter.This presented significant differences(P<0.05).With or without diabetes and different lesion location at varying layers and inter-layers,single-factor and multi-factor analysis revealed no effect on the association between positive ENT and age,history of stroke,white matter.Previous history of stroke,pathological changes of white matter,and age of onset,correlates with END which showed significant difference(P<0.05).Conclusions:There is a close relationship between the lesion location and other related factors,such as lesions of cerebral white matter,history of cerebral infarction,history of diabetes and age,etc.and END in patients with isolated acute lacunar infarction in basal ganglia.Protective factors of END included age≥65,high systolic pressure,stroke history,cerebral white matter lesions in our study.展开更多
Clarifying the pore structure characteristics of shale reservoirs,which are low porosity,low permeability and high heterogeneity,is an essential prerequisite for the efficient development of shale oil and gas.Fractal ...Clarifying the pore structure characteristics of shale reservoirs,which are low porosity,low permeability and high heterogeneity,is an essential prerequisite for the efficient development of shale oil and gas.Fractal theory is especially suited for characterizing the complex pore structures of shales.This work compares the pore structure characteristics between marine shales from the Longmaxi Formation and continental shales from the Shahejie Formation through low-temperature nitrogen adsorption,nuclear magnetic resonance,and scanning electron microscopy.Different fractal scaling models are adopted to determine the fractal dimensions and lacunarities of shales by low-temperature nitrogen adsorption data and scanning electron microscopy images.In addition,the mineral compositions from X-ray diffraction are analyzed to elucidate the mechanisms by which mineral content influences fractal dimensions.Finally,the correlations between total organic carbon content and microscopic structure are discussed.These results indicate that the pore size of marine shale is smaller than that of continental shale.Additionally,the fractal dimensions of marine shales are greater than that of continental shales,suggesting a more complex pore structure.The more quartz and clay content lead to greater complexity in pore space,resulting in higher fractal dimensions.The illite/smectite mixed layer shows a strong positive correlation with fractal dimensions for marine shales,whereas this correlation is less pronounced for continental shales.The presence of microfractures in organic matter leads to a reduction for the pore surface fractal dimension in continental shales.展开更多
文摘BACKGROUND A stroke is a significant brain event that impinges on individual motor or cognitive functions.In the lacunar stroke subtype of ischemic stroke,which results from blocked blood flow in certain brain areas,cases of dysarthria due to impaired blood flow are not uncommon.However,limited literature and research on the relevant pathophysiology and neural pathways exist.CASE SUMMARY We focus on a 60-year-old female with subacute stroke presenting symptoms including tongue deviation to the right,speech difficulty,choking on water,and biting the oral mucosa.She did not exhibit abnormalities in limb movement or sensation except for numbness in the tongue.We use single-photon emission computed tomography to reveal reduced blood flow in the left parietal lobe and bilateral temporal lobes.This report presents an atypical case of dysarthria,who exhibits abnormal articulation along with abnormal sensation and numbness in the tongue,prompting further investigation into the association between lacunar stroke subtypes,altered blood perfusion in affected brain regions,and neurological clinical status.CONCLUSION Dysarthria-plus syndrome in lacunar stroke isn’t solely related to motor function but also affects sensory function such as oral numbness.
基金supported by the National Natural Science Foundation of China (30671212)
文摘Normalized Difference Vegetation Index （NDVI） is a very useful feature for differentiating vegetation and non-vegetation in remote sensed imagery. In the light of the function of NDVI and the spatial patterns of the vegetation landscapes, we proposed the lacunarity texture derived from NDVI to characterize the spatial patterns of vegetation landscapes concerning the ＂gappiness＂ or ＂emptiness＂ characteristics. The NDVI-based lacunarity texture was incorporated into object-oriented classification for improving the identification of vegetation categories, especially Torreya which was the targeted tree species in the present research. A three-level hierarchical network of image objects was defined and the proposed texture was integrated as potential sources of information in the rules base. A knowledge base of rules created by classifier C5.0 indicated that the texture could potentially be applied in object-oriented classification. It was found that the addition of such texture improved the identification of every vegetation category. The results demonstrated that the texture could characterize the spatial patterns of vegetation structures, which could be a promising approach for vegetation identification.
文摘BACKGROUND The main pathological factor of cerebral infarction is atherosclerosis,which is the pathological process of chronic inflammatory diseases such as vascular smooth muscle hyperplasia,inflammatory cell infiltration,extracellular matrix increase,and thrombosis.At present,the focus of clinical treatment is anti-platelet aggregation and improving blood status,and current research is limited to improving symptoms only.AIM To observe the effect of sodium ozagrel and atorvastatin on type 2 diabetes patients with lacunar cerebral infarction.METHODS Eighty-two patients with type 2 diabetes and lacunar cerebral infarction admitted to our hospital from January 2018 to February 2020 were equally categorized into two groups according to their treatment method.The control group was administered atorvastatin,and the observation group was administered sodium ozagrel combined with atorvastatin.The National Institutes of Health stroke scale(NIHSS)score,activities of daily living(ADL)score,blood glucose,lipid levels,inflammatory factors,high-mobility group box 1(HMGB1)levels,paraoxonase-1(PON-1)levels,erythrocyte sedimentation rate(ESR),and macrophage migration inhibitory factor(MIF)levels were recorded before and after treatment.The total effective rate and adverse reaction rate of the two groups were analyzed.RESULTS The total effective rate of the observation group(94.00%)was significantly higher than that of the control group(80.00%)(χ2=3.998;P=0.046).The blood glucose indexes,total cholesterol levels,triglyceride levels,low-density lipoprotein cholesterol levels,high-sensitivity C-reactive protein levels,interleukin-1βlevels,tumor necrosis factor-αlevels,HMGB1 Levels,ESR,MIF levels,platelet aggregation rates,and plasma viscosity of the two groups decreased after treatment;however,high-density lipoprotein cholesterol and PON-1 Levels increased after treatment.After treatment,the blood glucose indexes;blood lipid indexes;inflammatory factors;HMGB1,PON-1,and MIF levels;ESR;platelet aggregation rate;and plasma viscosity of the observation group were better than those of the control group(P<0.05).After treatment,all patients in the observation group had higher ADL scores and lower NIHSS scores than those in the control group(P<0.05).CONCLUSION Sodium ozagrel with atorvastatin can reduce inflammatory reactions;regulate ESR and HMGB1,PON-1,and MIF levels;control blood glucose and lipid indexes;and alleviate nerve injury without increasing adverse effects of atorvastatin alone.
文摘This study semi-quantitatively analyzed the effects of leukoaraiosis.Patients with moderate or severe lacunar infarction were found to exhibit low scores on the Montreal Cognitive Assessment Scale （F=12.02,P=0.000）,and prolonged P300 Cz2.0 latency （F=16.04,P=0.000）.Correlation analysis revealed that the occurrence of leukoaraiosis was negatively correlated with Montreal Cognitive Assessment scores （r=-0.416,P=0.000）,and positively correlated with P300 Cz2.0 latency （r=0.538,P=0.000）.These findings indicate that leukoaraiosis aggravates cognitive impairment in patients with lacunar infarction,such that more severe leukoaraiosis is associated with more severe cognitive decline.
文摘Osteoporosis represents one major health condition for our growing elderly population. It accounts for severe morbidity and increased mortality in postmenopausal women and it is becoming an emerging health concern even in aging men. Screening of the population at risk for bone degeneration and treatment assessment of osteoporotic patients to prevent bone fragility fractures represent useful tools to improve quality of life in the elderly and to lighten the related socio-economic impact. Bone mineral density(BMD) estimate by means of dual-energy X-ray absorptiometry is normally used in clinical practice for osteoporosis diagnosis. Nevertheless, BMD alone does not represent a good predictor of fracture risk. From a clinical point of view, bone microarchitecture seems to be an intriguing aspect to characterize bone alteration patterns in aging and pathology. The widening into clinical practice of medical imaging techniques and the impressive advances in information technologies together with enhanced capacity of power calculation have promoted proliferation of new methods to assess changes of trabecular bone architecture(TBA) during aging and osteoporosis. Magnetic resonance imaging(MRI) has recently arisen as a useful tool to measure bone structure in vivo. In particular, high-resolution MRI techniques have introduced new perspectives for TBA characterization by non-invasive non-ionizing methods. However, texture analysis methods have not found favor with clinicians as they produce quite a few parameters whose interpretation is difficult. The introduction in biomedical field of paradigms, such as theory of complexity, chaos, and fractals, suggests new approaches and provides innovative tools to develop computerized methods that, by producing a limited number of parameters sensitive to pathology onset and progression, would speed up their application into clinical practice. Complexity of living beings and fractality of several physio-anatomic structures suggest fractal analysis as a promising approach to quantify morphofunctional changes in both aging and pathology. In this particular context, fractal lacunarity seems to be the proper tool to characterize TBA texture as it is able to describe both discontinuity of bone network and sizes of bone marrow spaces, whose changes are an index of bone fracture risk. In this paper, an original method of MRI texture analysis, based on TBA fractal lacunarity is described and discussed in the light of new perspectives for early diagnosis of osteoporotic fractures.
基金Under the auspices of National Natural Science Foundation of China (No.40930531,41171320,41001301)
文摘The spatial structure characteristics of landform are the foundation of geomorphologic classification and recognition.This paper proposed a new method on quantifying spatial structure characteristics of terrain surface based on improved 3D Lacunarity model.Lacunarity curve and its numerical integration are used in this model to improve traditional classification result that different morphological types may share the close value of indexes based on global statistical analysis.Experiments at four test areas with different landform types show that improved 3D Lacunarity model can effectively distinguish different morphological types per texture analysis.Higher sensitivity in distinguishing the tiny differences of texture characteristics of terrain surface shows that the quantification method by 3D Lacu-narity model and its numerical integration presented in this paper could contribute to improving the accuracy of land-form classifications and relative studies.
基金the General Program of National Natural Science Foundation of China,No.30870125
文摘The genes for 5-1ipoxygenase activating protein （ALOX5AP） and phosphodiesterase 4D （PDE4D） have been demonstrated as susceptibility genes for lacunar in the Icelandic and Pakistani populations, but little is known about the role of these genes in Chinese populations. The present study utilized polymerase chain reaction and ligase detection reaction to detect single nucleotide polymorphisms （SNPs） in 280 consecutive stroke patients and 258 unrelated population-based controls from Nanjing, Jiangsu Province, China. The allele frequency, genotypes, and haplotypes of the two SNPs （rs456009 and rs966221） in PDE4D were similar between the two groups. However, A allele frequency of rs4073259 （A/G） and rs4769055 （A/C） in the ALOX5AP gene exhibited differences in two groups, and especially the haplotype of the SNP was significantly different between the two groups. Results suggested that the ALOX5AP gene might be involved in lacunar infarct, while PDE4D gene was not a risk factor for lacunar infarct in individuals from Jiangsu Province, China.
基金This study was supported by Shaanxi Science Technology Study Development Plan Item(No.2006K13-G7-6)Xi'an Science Technology Study Development Plan Item(No.GG05140).
文摘Objective To study the relationships between cognitive impairment in patients with lacunar infarcts and quantitative CT measures and to determine the independent correlative factors of cognitive impairment.Methods Neuropsychological examination was conducted for 128 patients with acute lacunar infarct.Number,location,and volume of infarcts,cerebral atrophy index and severity of white matter lesions(WMLs) were measured and recorded.Results The number of lacunar infarcts in cognitive impairment (CI) group was significantly larger than that in cognitive normal(CN) group.Mean width of sulcus and sylvian fissure,index of frontal horn and ventricular-brain ratio(VBR) were significantly different in both groups.There were more patients with 3 grades or 4 grades WMLs in CI group(62%) than those in CN group(22%).The total volume of lacunar infarcts showed no statistically significant difference.Logistic regression analysis indicated that the number of lacunar infarcts in frontal subcortex and thalamus,the volume of infarcts in anterior periventricular white matter,width of cerebral sulcus and sylvian fissure were correlated with cognitive impairment respectively.Additionally,age and education were correlative factors of cognitive impairment in patients with lacunar infarct.Conclusion Correlative factors of cognitive impairment in patients with lacunar infarct are not merely one feature,but a combination of infarct features(number,location,and volume),cortical atrophy and host factors(age and education).
基金Supported by National Natural Science Foundation of China(No.81500726)Health Research Program of Shaanxi,China(No.2014E12)Shaanxi Health Research Foundation(No.2016E007)。
文摘AIM:To investigate the correlation of ischemic ophthalmopathy(IO)with lacunar infarction(LI),an ischemic lesions in the cerebrovascular system.METHODS:Totally 204 cases of IO without any nervous system symptom and previously diagnosed LI served as the observational group.All 204 cases without IO,nervous system symptoms and previous LI served as the control group.Age and sex between the two groups matched well.LI was diagnosed by magnetic resonance imaging(MRI)and the results of the two groups were statistically analyzed and compared.RESULTS:IO included 174 eyes of 156 patients with non-arteritis anterior ischemic optic neuropathy(NAION),42 eyes of 36 patients with central retinal artery occlusion(CRAO)or branch retinal artery occlusion(BRAO)and 12 eyes of 12 patients with ocular ischemia syndrome(OIS).The detection rate of LI(72.54%)in IO group was obviously higher than that(15.68%)in the control group(P<0.001).IO was positively correlated with LI(r=0.573,P<0.05).In addition,most infarction sites located in the basal ganglia(67.57%),which were not the vital areas of cerebrum and not easy to be found due to their small size.The majority of those first visited IO patients(72.54%)without nervous system symptom and previously diagnosed LI had already suffered from LI.CONCLUSION:According to our studies,there is a positive correlation between IO and LI.IO can be used as an important predictor for the present of LI,especially obvious signs of the patient.
文摘Objective We conducted a study using MRI and ambulatory blood pressure monitoring(ABPM) to determine whether an in-apporpriately low nocturnal blood pressure, or an excess fall in nocturnal blood pressure, might be responsible for lacunar infarct. Method ABPM and Casul blood pressure(CBP) were examined in 35 hypertentives with lacunar infarct(LI)and 33 hypertentives without lacunar infarct as control group. Results There is no significant difference of CBP between two groups. But the mean nighttime systolic blood pressure (nSBP) and diastolic blood pressure (nDBP) in patients with lacunar infarct were significantly smaller than in patients without lacunar infarct. The ratio of nSBP/dSBP and nDBP/dDBP in SI were smaller than in control group respectively. Conclusions The results indicate that an inap-propriately low nocturnal blood pressure, or an excessive fall in nocturnal blood pressure, is associated with lacunar infarct. It is necessary not only to control high blood pressure but also to pay attention to circadian changes of blood pressure during the course of anti-hypertensive treatment.
文摘A 59 year old white male presented with a clinical picture typical of lacunar stroke. However, a thorough diagnostic work up showed that the most probable mechanism of stroke was paradoxical brain embolism through a patent foramen ovale. The clinical-neuroradiological mismatch that ultimately lead to the correct interpretation is discussed.
文摘Pure motor stroke(PMS), also known as pure motor hemiparesis, is the most common of any lacunar form(between one half and two thirds of cases, depending on the series). In an acute stroke registry, 733 patients presented a lacunar infarct and PMS accounted for 12.7%(n = 342) of all first-ever stroke patients and for 48% of all lacunar syndromes. The posterior limb of the internal capsule, corona radiata, and pons are the most frequent brain topographies. Infarcts in the mesencephalus or medullary pyramid have been exceptionally reported. This present update is focused on the clinical evidence and mechanisms underlying the relationship between PMS and different stroke etiologies.
文摘Objective: To investigate the diagnostic effects of CT and magnetic resonance imaging (MRI) in patients with lacunar infarction. Methods: Thirty patients with early lacunar infarction in our hospital were diagnosed by ct and 30 patients were diagnosed by magnetic resonance imaging according to the examination time, the average diameter of infarct focus and examination cost. Vascular image quality (siphon segment score of internal carotid artery, petrous segment score of artery, posterior communicating artery score and basilar artery score), and the lesion detection rates of the two inspection methods were compared;Results The detection effect of MRI was superior to that of ct (P < 0.05). Conclusion: patients with lacunar infarction by magnetic resonance imaging technology and ct two ways of diagnosis, can get good diagnosis effect, but the magnetic resonance imaging technology to detect the infarct diameter is larger, the diagnosis effect is better, the detection time is shorter, however, the examination cost is more, can according to the needs of patients in clinical reasonable choice of examination methods.
文摘Objective:To investigate,in basal ganglia,the factors associated with early neurological deterioration(END)of isolated acute lacunar infarction.Methods:167 patients,in the retrospective group,with isolated acute lacunar infarction in basal ganglia,were defined by magnetic resonance imaging(MRI).The National Institutes of Health Stroke Scale(NIHSS)defined early neurological deterioration as increases of≥2 within 72 hours following admission.Baseline variables predicting END were investigated with multivariate logistic regression analysis.Results:In the study,END occurred in 42(25.15%)patients.Lesions located in posterior limb of internal capsule were independent risk factors for END(P<0.01).Associated with END were the age of onset,history of cerebral infarction,history of diabetes,systolic blood pressure at admission and lesions of cerebral white matter.This presented significant differences(P<0.05).With or without diabetes and different lesion location at varying layers and inter-layers,single-factor and multi-factor analysis revealed no effect on the association between positive ENT and age,history of stroke,white matter.Previous history of stroke,pathological changes of white matter,and age of onset,correlates with END which showed significant difference(P<0.05).Conclusions:There is a close relationship between the lesion location and other related factors,such as lesions of cerebral white matter,history of cerebral infarction,history of diabetes and age,etc.and END in patients with isolated acute lacunar infarction in basal ganglia.Protective factors of END included age≥65,high systolic pressure,stroke history,cerebral white matter lesions in our study.
基金supported by the National Natural Science Foundation of China(Grant Nos.42172159,42302143,and 52404048).
文摘Clarifying the pore structure characteristics of shale reservoirs,which are low porosity,low permeability and high heterogeneity,is an essential prerequisite for the efficient development of shale oil and gas.Fractal theory is especially suited for characterizing the complex pore structures of shales.This work compares the pore structure characteristics between marine shales from the Longmaxi Formation and continental shales from the Shahejie Formation through low-temperature nitrogen adsorption,nuclear magnetic resonance,and scanning electron microscopy.Different fractal scaling models are adopted to determine the fractal dimensions and lacunarities of shales by low-temperature nitrogen adsorption data and scanning electron microscopy images.In addition,the mineral compositions from X-ray diffraction are analyzed to elucidate the mechanisms by which mineral content influences fractal dimensions.Finally,the correlations between total organic carbon content and microscopic structure are discussed.These results indicate that the pore size of marine shale is smaller than that of continental shale.Additionally,the fractal dimensions of marine shales are greater than that of continental shales,suggesting a more complex pore structure.The more quartz and clay content lead to greater complexity in pore space,resulting in higher fractal dimensions.The illite/smectite mixed layer shows a strong positive correlation with fractal dimensions for marine shales,whereas this correlation is less pronounced for continental shales.The presence of microfractures in organic matter leads to a reduction for the pore surface fractal dimension in continental shales.
