In vivo label-free measurement of blood flow velocity symmetry based on dual line scanning third-harmonic generation microscopy excited at the 1700 nm window

Measurement of bloodflow velocity is key to understanding physiology and pathology in vivo.While most measurements are performed at the middle of the blood vessel,little research has been done on characterizing the instantaneous bloodflow velocity distribution.This is mainly due to the lack of measurement technology with high spatial and temporal resolution.Here,we tackle this problem with our recently developed dual-wavelength line-scan third-harmonic generation(THG)imaging technology.Simultaneous acquisition of dual-wavelength THG line-scanning signals enables measurement of bloodflow velocities at two radially symmetric positions in both venules and arterioles in mouse brain in vivo.Our results clearly show that the instantaneous bloodflow velocity is not symmetric under general conditions.

Unveiling the silent link:Normal-tension glaucoma's enigmatic bond with cardiac blood flow

This comprehensive review embarks on a captivating journey into the complex relationship between cardiology and normal-tension glaucoma(NTG),a condition that continues to baffle clinicians and researchers alike.NTG,characterized by optic nerve damage and visual field loss despite normal intraocular pressure,has long puzzled clinicians.One emerging perspective suggests that alterations in ocular blood flow,particularly within the optic nerve head,may play a pivotal role in its pathogenesis.While NTG shares commonalities with its high-tension counterpart,its unique pathogenesis and potential ties to cardiovascular health make it a fascinating subject of exploration.It navigates through the complex web of vascular dysregulation,blood pressure and perfusion pressure,neurovascular coupling,and oxidative stress,seeking to uncover the hidden threads that tie the heart and eyes together in NTG.This review explores into the intricate mechanisms connecting cardiovascular factors to NTG,shedding light on how cardiac dynamics can influence ocular health,particularly in cases where intraocular pressure remains within the normal range.NTG's enigmatic nature,often characterized by seemingly contradictory risk factors and clinical profiles,underscores the need for a holistic approach to patient care.Drawing parallels to cardiac health,we examine into the shared vascular terrain connecting the heart and the eyes.Cardiovascular factors,including systemic blood flow,endothelial dysfunction,and microcirculatory anomalies,may exert a profound influence on ocular perfusion,impacting the delicate balance within the optic nerve head.By elucidating the subtle clues and potential associations between cardiology and NTG,this review invites clinicians to consider a broader perspective in their evaluation and management of this elusive condition.As the understanding of these connections evolves,so too may the prospects for early diagnosis and tailored interventions,ultimately enhancing the quality of life for those living with NTG.

Cerebral arterial blood flow,attention,and executive and cognitive functions in depressed patients after acute hypertensive cerebral hemorrhage

BACKGROUND Intracerebral hemorrhage mainly occurs in middle-aged and elderly patients with hypertension,and surgery is currently the main treatment for hypertensive cerebral hemorrhage,but the bleeding caused by surgery will cause damage to the patient's nerve cells,resulting in cognitive and motor dysfunction,resulting in a decline in the patient's quality of life.AIM To investigate associations between cerebral arterial blood flow and executive and cognitive functions in depressed patients after acute hypertensive cerebral hemorrhage.METHODS Eighty-nine patients with depression after acute hypertensive cerebral hemorrhage who were admitted to our hospital between January 2019 and July 2021 were selected as the observation group,while 100 patients without depression who had acute hypertensive cerebral hemorrhage were selected as the control group.The attention span of the patients was assessed using the Paddle Pin Test while executive function was assessed using the Wisconsin Card Sorting Test(WCST)and cognitive function was assessed using the Montreal Cognitive Assessment Scale(MoCA).The Hamilton Depression Rating Scale(HAMD-24)was used to evaluate the severity of depression of involved patients.Cerebral arterial blood flow was measured in both groups.RESULTS The MoCA score,net scores I,II,III,IV,and the total net score of the scratch test in the observation group were significantly lower than those in the control group(P<0.05).Concurrently,the total number of responses,number of incorrect responses,number of persistent errors,and number of completed responses of the first classification in the WCST test were significantly higher in the observation group than those in the control group(P<0.05).Blood flow in the basilar artery,left middle cerebral artery,right middle cerebral artery,left anterior cerebral artery,and right anterior cerebral artery was significantly lower in the observation group than in the control group(P<0.05).The basilar artery,left middle cerebral artery,right middle cerebral artery,left anterior cerebral artery,and right anterior cerebral artery were positively correlated with the net and total net scores of each part of the Paddle Pin test and the MoCA score(P<0.05),and negatively correlated with each part of the WCST test(P<0.05).In the observation group,the post-treatment improvement was more prominent in the Paddle Pin test,WCST test,HAMD-24 score,and MoCA score compared with those in the pre-treatment period(P<0.05).Blood flow in the basilar artery,left middle cerebral artery,right middle cerebral artery,left anterior cerebral artery,and right anterior cerebral artery significantly improved in the observation group after treatment(P<0.05).CONCLUSION Impaired attention,and executive and cognitive functions are correlated with cerebral artery blood flow in patients with depression after acute hypertensive cerebral hemorrhage and warrant further study.

Predicting Acute Mountain Sickness Using Regional Sea-Level Cerebral Blood Flow

Objective To investigate the role of sea-level cerebral blood flow(CBF)in predicting acute mountain sickness(AMS)using three-dimensional pseudo-continuous arterial spin labeling(3D-pCASL).Methods Forty-eight healthy volunteers reached an altitude of 3,650 m by air after undergoing a head magnetic resonance imaging(MRI)including 3D-pCASL at sea level.The CBF values of the bilateral anterior cerebral artery(ACA),middle cerebral artery(MCA),posterior cerebral artery(PCA),and posterior inferior cerebellar artery(PICA)territories and the laterality index(LI)of CBF were compared between the AMS and non-AMS groups.Statistical analyses were performed to determine the relationship between CBF and AMS,and the predictive performance was assessed using receiver operating characteristic(ROC)curves.Results The mean cortical CBF in women(81.65±2.69 mL/100 g/min)was higher than that in men(74.35±2.12 mL/100 g/min)(P<0.05).In men,the cortical CBF values in the bilateral ACA,PCA,PICA,and right MCA were higher in patients with AMS than in those without.Cortical CBF in the right PCA best predicted AMS(AUC=0.818).In women,the LI of CBF in the ACA was different between the AMS and non-AMS groups and predicted AMS with an AUC of 0.753.Conclusion Although the mechanism and prediction of AMS are quite complicated,higher cortical CBF at sea level,especially the CBF of the posterior circulatory system,may be used for prediction in male volunteers using non-invasive 3D-pCASL.

Modeling Blood Flow in Veins of Uniform Properties (Giraffe Jugular Vein)

This paper models the giraffe’s jugular veins as a uniform collapsible tube from a rigid skull. The equations governing one-dimensional steady flow through such a tube for various conditions have been developed. The effects of inertial and inclination angles that have not been discussed previously have been included. It has been shown that different flows for a uniform tube (vein) are possible. However, this flow matches that of a jugular vein which is supercritical, and the steady solution has been given by the balance between the driving forces of gravity and the viscous resistance to the flow at the right atrium of the heart must be sub-critical for a fixed right-atrium pressure which means that an elastic jump is required to return the flow to sub-critical from the supercritical flow upstream this type of relationship gives rise to flow limitation at the same time given any right atrium fixed pressure there exists a maximum flow rate which when exceeded the boundary conditions of the flow do not hold boundary conditions at the right atrium are not satisfied hence making the steady flow impossible this mechanism of flow limitation is slightly different from the other one in that causes airways through forced expiration from the observation made it is clearly shown that there is an intravascular pressure difference with a change in height.

Dynamic Non-Invasive Detection of NADH Based on Blood Flow-Mediated Skin Fluorescence (FMSF) Method

Nicotinamide adenine dinucleotide (NADH/NAD+) is involved in important biochemical reactions in human metabolism, including participation in energy production by mitochondria. The changes in fluorescence intensity as a function of time in response to blocking and releasing of blood flow in a forearm are used as a measure of oxygen transport with blood to the tissue, which directly correlates with the skin microcirculation status. In this paper, a non-invasive dynamic monitoring system based on blood flow-mediated skin fluorescence (FMSF) technology is developed to monitor the NADH fluorescence intensity of skin tissue during the process of blocking reactive hyperemia. Simultaneously, laser speckle contrast imaging (LSCI) and laser Doppler flowmetry (LDF) were used to observe blood flow, blood oxygen saturation (SOt2) and relative amount of hemoglobin (rHb) during the measurement process, which helped to explore NADH dynamics relevant physiological changes. A variety of parameters have been derived to describe NADH fluorescence curve based on the FMSF device. The experimental results are conducive to understanding the NADH measurement and the physiological processes related to it, which help FMSF to be a great avenue for in vivo physiological, clinical and pharmacological research on mitochondrial metabolism.

Regulation of hepatic blood flow:The hepatic arterial buffer response revisited

The interest in the liver dates back to ancient times when it was considered to be the seat of life processes. The liver is indeed essential to life,not only due to its complex functions in biosynthesis,metabolism and clearance,but also its dramatic role as the blood volume reservoir. Among parenchymal organs,blood flow to the liver is unique due to the dual supply from the portal vein and the hepatic artery. Knowledge of the mutual communication of both the hepatic artery and the portal vein is essential to understand hepatic physiology and pathophysiology. To distinguish the individual importance of each of these inflows in normal and abnormal states is still a challenging task and the subject of on-going research. A central mechanism that controls and allows constancy of hepatic blood flow is the hepatic arterial buffer response. The current paper reviews the relevance of this intimate hepatic blood flow regulatory system in health and disease. We exclusively focus on the endogenous interrelationship between the hepatic arterial and portal venous inflow circuits in liver resection and transplantation,as well as inflammatory and chronic liver diseases. We do not consider the hepatic microvascular anatomy,as this has been the subject of another recent review.

子宫动脉血流频谱联合e-Flow胎盘血流在妊娠期高血压103例中的应用价值

目的研究e-Flow胎盘血流结合子宫动脉血流频谱在妊娠期高血压疾病中的应用价值。方法回顾性分析2021年5月至2023年2月邯郸市中心医院103例纳入时无高血压,后随访出现妊娠期高血压孕妇作为妊娠期高血压组,选择产检正常且无高血压的110例正常孕妇作为健康组。收集妊娠期高血压组未出现高血压时以及健康组的子宫动脉血流频谱和e-Flow胎盘血流数据,获得子宫动脉阻力指数、搏动指数、收缩期峰值与舒张末期流速比值(S/D),舒张早期切迹与胎盘血管图像;采用受试者操作特征曲线(ROC曲线)分析各指标单独以及联合预测妊娠期高血压的价值。结果妊娠期高血压组搏动指数、阻力指数及S/D值高于健康组(P<0.05)。子宫动脉舒张早期切迹存在率方面,妊娠期高血压组相较于健康组更高(P<0.05)。妊娠期高血压组三级绒毛动脉计数少于健康组[(2.34±0.48)个比(4.36±0.53)个,P<0.05]。ROC曲线显示,搏动指数、阻力指数、S/D、三级绒毛动脉计数联合检查对妊娠期高血压的灵敏度、特异度为74.80%、93.30%,预测价值高于单独检查。结论子宫动脉血流频谱联合e-Flow胎盘血流能有效预测妊娠期高血压发生,可作为临床早期疾病评估的有效检查方式。

Skeletal Blood Flow in Bone Repair and Maintenance

Bone is a highly vascularized tissue, although this aspect of bone is often overlooked. In this article, the importance of blood flow in bone repair and regeneration will be reviewed. First, the skeletal vascular anato- my, with an emphasis on long bones, the distinct mechanisms for vascularizing bone tissue, and methods for remodeling existing vasculature are discussed. Next, techniques for quantifying bone blood flow are briefly summarized. Finally, the body of experimental work that demonstrates the role of bone blood flow in fracture healing, distraction osteogenesis, osteoporosis, disuse osteopenia, and bone grafting is examined. These results illustrate that adequate bone blood flow is an important clinical consideration, particularly during bone regeneration and in at-risk patient groups.

Insulin action in muscle and adipose tissue in type 2 diabetes:The significance of blood flow

Under normal metabolic conditions insulin stimulates microvascular perfusion(capillary recruitment) of skeletal muscle and subcutaneous adipose tissue and thus increases blood flow mainly after meal ingestion or physical exercise.This helps the delivery of insulinitself but also that of substrates and of other signalling molecules to multiple tissues beds and facilitates glucose disposal and lipid kinetics.This effect is impaired in insulin resistance and type 2 diabetes early in the development of metabolic dysregulation and reflects early-onset endothelial dysfunction.Failure of insulin to increase muscle and adipose tissue blood flow results in decreased glucose handling.In fat depots,a blunted postprandial blood flow response will result in an insufficient suppression of lipolysis and an increased spill over of fatty acids in the circulation,leading to a more pronounced insulin resistant state in skeletal muscle.This defect in blood flow response is apparent even in the prediabetic state,implying that it is a facet of insulin resistance and exists long before overt hyperglycaemia develops.The following review intends to summarize the contribution of blood flow impairment to the development of the atherogenic dysglycemia and dyslipidaemia.

The micropolar fluid model for blood flow through a tapered artery with a stenosis

A micropolar model for axisymmetric blood flow through an axially nonsymmetreic but radially symmetric mild stenosis tapered artery is presented. To estimate the effect of the stenosis shape, a suitable geometry has been considered such that the axial shape of the stenosis can be changed easily just by varying a parameter （referred to as the shape parameter）. The model is also used to study the effect of the taper angle Ф. Flow parameters such as the velocity, the resistance to flow （the resistance impedance）, the wall shear stress distribution in the stenotic region and its magnitude at the maximum height of the stenosis （stenosis throat） have been computed for different values of the shape parameter n, the taper angle Ф, the coupling number N and the micropolar parameter m. It is shown that the resistance to flow decreases with increasing the shape parameter n and the micropolar parameter m while it increases with increasing the coupling number N. So, the magnitude of the resistance impedance is higher for a micropolar fluid than that for a Newtonian fluid model. Finally, the velocity profile, the wall shear stress distribution in the stenotic region and its magnitude at the maximum height of the stenosis are discussed for different values of the parameters involved on the problem.

Influence of magnetic field and Hall currents on blood flow through a stenotic artery

A micropolar model for blood simulating magnetohydrodynamic flow through a horizontally nonsymmetric but vertically symmetric artery with a mild stenosis is presented. To estimate the effect of the stenosis shape, a suitable geometry has been considered such that the horizontal shape of the stenosis can easily be changed just by varying a parameter referred to as the shape parameter. Flow parameters, such as velocity, the resistance to flow （the resistance impedance）, the wall shear stress distribution in the stenotic region, and its magnitude at the maximum height of the stenosis （stenosis throat）, have been computed for different shape parameters, the Hartmann number and the Hall parameter. This shows that the resistance to flow decreases with the increasing values of the parameter determining the stenosis shape and the Hail parameter, while it increases with the increasing Hartmann number. The wall shear stress and the shearing stress on the wall at the maximum height of the stenosis possess an inverse characteristic to the resistance to flow with respect to any given value of the Hartmann number and the Hall parameter. Finally, the effect of the Hartmann number and the Hall parameter on the horizontal velocity is examined.

Predicting Endometrium Receptivity with Parameters of Spiral Artery Blood Flow

In order To evaluate whether the parameters of spiral artery blood flow, as measured by transvaginal color Doppler, may be used to assess endometrium receptivity prior to embryo transfer (ET), a retrospective study of 94 infertile women who had undergone ART treatments with different outcomes (pregnant or nonpregnant) was done. Subendometrial blood flow was evaluated. The resistance index (RI), systolic/diastolic ratio (S/D) and pulsatility index (PI) were significantly lower in those who achieved pregnancy as compared with those who did not: 0.62±0.04 vs 0.68±0.04 (P<0.001), 2.66±0.33 vs 3.19±0.39 (P<0.01) and 1.15±0.17 vs 1.34±0.22 (P<0.05), respectively. Furthermore, when RI>0.72, PI>1.6, and S/D>3.6, no pregnancy occurred. These data suggest that the parameters of spiral artery blood flow could be used as a new assay in predicting endometrial receptivity before ET.

Correlation between intracoronary thrombus components and coronary blood flow after percutaneous coronary intervention for acute myocardial infarction at different onset time

BACKGROUND Acute myocardial infarction(AMI)is a leading cause of mortality.Early reperfusion to restore blood flow is crucial to successful treatment.In the current reperfusion regimen,an increasing number of patients have benefited from direct percutaneous coronary intervention(PCI).In order to understand whether there is a correlation between the components of coronary thrombosis and the absence of reflow or slow blood flow after coronary stent implantation in direct PCI,we collected data on direct PCI cases in our hospital between January 2016 and November 2018.AIM To investigate the correlation between intracoronary thrombus components and coronary blood flow after stent implantation in direct PCI in AMI.METHODS We enrolled 154 patients(85 male and 69 female,aged 36–81 years)with direct PCI who underwent thrombus catheter aspiration within<3,3–6 or 6–12 h of onset of AMI between January 2016 and November 2018.The thrombus was removed for pathological examination under a microscope.The patients of the three groups according to the onset time of AMI were further divided into those with a white or red thrombus.The thrombolysis in myocardial infarction(TIMI)blood flow after stent implantation was recorded based on digital subtraction angiography during PCI.The number of patients with no-reflow and slow blood flow in each group was counted.Statistical analysis was performed based on data such as onset time,TIMI blood flow.RESULTS There were significant differences in thrombus components between the patients with acute ST-segment elevation myocardial infarction and non-ST-segment elevation myocardial infarction(P<0.01).In the group with PCI<3 h after onset of AMI,there was no significant difference in the incidence of no-reflow and slow-flow between the white and red thrombus groups.In the groups with PCI 3-6 and 6-12 h after onset of AMI,there was a significant difference in the incidence of no-reflow and slow-flow between the white and red thrombus groups(P<0.01).There was a significant correlation between the onset time of AMI and the occurrences of no-reflow and slow blood flow during PCI(P<0.01).CONCLUSION In direct PCI,the onset time of AMI and color of coronary thrombus are often used to predict whether there will be no reflow or slow blood flow after stent implantation.

Effects of intestinal mucosal blood flow and motility on intestinal mucosa

AIM： To investigate the role of intestinal mucosal blood flow （IMBF） and motility in the damage of intestinal mucosal barrier in rats with traumatic brain injury. METHODS： Sixty-four healthy male Wistar rats were divided randomly into two groups： traumatic brain injury （TBI） group （n = 32）, rats with traumatic brain injury; and control group （n = 32）, rats with sham-operation. Each group was divided into four subgroups （n = 8） as 6, 12, 24 and 48 h after operation. Intestinal motility was measured by the propulsion ratio of a semi-solid colored marker （carbon-ink）. IMBF was measured with the laser-Doppler technique. Endotoxin and D-xylose levels in plasma were measured to evaluate the change of intestinal mucosal barrier function following TBI. RESULTS： The level of endotoxin was significantly higher in TBI group than in the control group at each time point （0.382 ± 0.014 EU/mL vs 0.102 ± 0.007 EU/mL, 0.466 ± 0.018 EU/mL vs 0.114 ± 0.021 EU/mL, 0.478± 0.029 EU/mL vs 0.112 ±- 0.018 EU/mL and 0.412± 0.036 EU/mL vs 0.108 ±0.011 EU/mL, P 〈 0.05）. D-xylose concentrations in plasma in TBI group were significantly higher than in the control group （6.68 ± 2.37 mmol/L vs 3.66 ±1.07 retool/L, 8.51 ± 2.69 mmol/L vs 3.15 ＋ 0.95 mmol/L, 11.68 ±3.24 mmol/L vs 3.78 ± 1.12 mmol/L and 10.23 ± 2.83 mmol/L vs 3.34 ± 1.23 mmol/L, P 〈 0.05）. The IMBF in TBI group was significantly lower than that in the control group （38.5 ± 2.8 PU vs 45.6 ± 4.6 PU, 25.2 ± 3.1 PU vs 48.2 ± 5.3 PU, 21.5 ± 2.7 PU vs 44.9 ± 2.8 PU, 29. 4 ± 3.8 PU vs 46.7 ± 3.2 PU） （P 〈 0.05）. Significant decelerations of intestinal propulsion ratio in T8I groups were found compared with the control group （0.48% ± 0.06% vs 0.62%± 0.03%, 0.37% ±0.05% vs 0.64% ± 0.01%, 0.39% ± 0.07% vs 0.63% =1= 0.05% and 0.46% ± 0.03% vs 0.65% ± 0.02%） （P 〈 0.05）. CONCLUSION： The intestinal mucosal permeability is increased obviously in TBI rats. Decrease of intestinal motility and IMBF occur early in TBI, both are important pathogenic factors for stress-related damage of the intestinal mucosal barrier in TBI.

Hyperbaric oxygen therapy for cerebral blood flow and electroencephalogram in patients with acute cerebral infarction Choice for therapeutic occasion

BACKGROUND： Hyperbaric oxygen （HBO） therapy increases blood oxygen content, changes cerebral blood flow （CBF） and cerebral metabolism. Its therapeutic effects on cerebrovascular disease have been fully confirmed, but the occasion for HBO therapy is still unclear. OBJECTIVE： To observe the therapeutic effects of HBO therapy at different time on CBF and electroencephalogram （EEG） in patients with acute cerebral infarction （CI）. DESIGN： Randomized controlled trial. SETTING： Department of Neurology, Shidong Hospital, Yangpu District of Shanghai. PARTICIPANTS： Ninety-six inpatients with acute CI, admitted to Department of Neurology, Shidong Hospital, Yangpu District of Shanghai from January 2001 to December 2006, were involved in this experiment. The involved participants met the diagnosis criteria of acute CI and confirmed by skull CT or MRI. They all were patients with moderate CI （16- 30 points） according to neurologic deficit score formulated by Chinese Medical Association. Informed consents of detected items and therapeutic regimen were obtained from all the involved participants. They were randomized into two groups with 48 in each： early-stage treatment group and advanced-stage treatment group. Among the 48 patients in the early-stage treatment group, 21 male and 27 female, aged 53 -68 years, 22 patients were found with basal ganglia infarction, 10 with brain lobe infarction, 16 with multiple infarction, 27 accompanied with hypertension and 2 accompanied with diabetes meUitus. Among the 48 patients in the advanced-stage treatment group, 23 male and 25 female, aged 52 - 71 years, 25 patients were found with basal ganglia infarction, 10 with brain lobe infarction, 12 with multiple infarction, 1 with brain stem infarction, 28 accompanied with hypertension and 1 accompanied with diabetes mellitus. METHODS： After admission, patients of two groups received routine drug treatment. ① Patients in the early-stage treatment group and advanced-stage treatment group began to receive HBO therapy within one week of CI and 4 weeks after CI, respectively. The total course of treatment both was 2 weeks. EEG examination was carried out before and after therapy, and CBF was determined with ^133Xe inhalation.② Assessment criteria of curative effects： Basically cured： neurologic symptoms and body signs disappeared, could work and do housework; Markedly effective： score of neurologic deficit was decreased by over 21 points, could manage himself/herself partially; Effective： score of neurologic deficit was decreased by 8 to 12 points; Non-effective： Score was increased or decreased less than 8 points, neurologic deficit was worsened, even died. Total effective rate = （number of cured＋number of markedly effective＋number of effective）/ number of total cases ×100%. ③ t test and Chi-square test were used for comparing the difference of measurement data and enumeration data respectively, and Ridit analysis was used for comparing the difference of clinical curative effects. MAIN OUTCOME MEASURES： ① Comparison of EEG and CBF of patients from two groups before and after treatment. ②Comparison of post-treatment neurologic deficit of patients between two groups. RESULTS： All the involved 96 patients with CI participated in the final analysis. ① Clinical symptoms of patients from two groups after therapy were significantly improved as compared with those before therapy, and curative effects of early treatment group were better than those of advanced treatment group （ U = 1.99, P 〈 0.05 ） . ②After treatment, CBF in each region of brains, except for that in parietal lobe of patients in the advanced-stage treatment group, was significantly improved （P 〈 0.05 - 0.01）; The improvement of CBF of patients in the early-stage treatment group was more obvious than that in the early-stage treatment group （P 〈 0.05 - 0.01）. ③ The abnormal rate of EEF of patients from early-stage treatment group and advanced-stage treatment group before treatment was 94% and 96%, respectively. After treatment, improvement rate of EEG of patients in the early-stage treatment groulp was 95%, which was significantly different from that in the advanced-stage treatment group （82%, x^2=4.32, P 〈 0.05 ） CONCLUSION： HBO therapy both at early and advanced stages of CI （within 1 week and 4 weeks after CI attack） can improve CBF and EEG of patients with early CI, especially.

Measurements Of Cerebral Blood Flow in Postasphyxiated Newborns by Color Doppler Imaging（CDI）

Cerebral blood flow of 10 asphyxiated term newborns was continuously measured during the first 7 days of life and compared with that of 10 normal term infants by CDI. Frequency spectrum and blood flow variables in the anterior, middle and posterior cerebral arteries were studied. The results showed evidently lower systolic amplitude in patients than that in normal subjects. End diastolic amplitude was zero in part of vessels, and values of bloed flow variables were all lower in day 1 of the life as compared with the control groups. Frequency spectrum recovered to normal patterns in 9 survived infants in day 2. but blood flow variables recovered to normal by day 7. Values of resistance index (RI) rose to 1 in some vessels of moderate hypoxic ischemic encephalopathy (HIE) infants and stayed at 1 in the severe HIE infants. It is concluded that low CBF plays a key role in brain damage of post-asphyxiated newborns and RI may be an important parameter in the evaluation prognosis.

Non invasive blood flow measurement in cerebellum detects minimal hepatic encephalopathy earlier than psychometric tests

AIM: To assess whether non invasive blood flow measurement by arterial spin labeling in several brain regions detects minimal hepatic encephalopathy.

Electroosmotic oscillatory flow of micropolar fluid in microchannels:application to dynamics of blood flow in microfluidic devices

The electroosmotic flow of a micropolar fluid in a microchannel bounded by two parallel porous plates undergoing periodic vibration is studied. The equations for conservation of linear and angular momentums and Gauss＇s law of charge distribution are solved within the framework of the Debye-Hückel approximation. The fluid velocity and microrotation are assumed to depend linearly on the Reynolds number. The study shows that the amplitude of microrotation is highly sensitive to the changes in the magnitude of the suction velocity and the width of the microchannel. An increase in the micropolar parameter gives rise to a decrease in the amplitude of microrotation. Numerical estimates reveal that the microrotation of the suspended microelements in blood also plays an important role in controlling the electro-osmotically actuated flow dynamics in microbio-fluidic devices.

Effects of electroacupuncture on microcirculatory blood flow and glucose transporter function in the hippocampus

Nerve cell metabolism in post brain ischemia depends on increased microcirculation perfusion and transport function of microvascular endothelial cells. In the present study, a rat model of middle cerebral artery occlusion was established to investigate the influence of electroacupuncture （EA） on hippocampal CA1 cerebral blood flow and glucose transporter 1 （GLUT1） expression in the microvascular endothelial cells. Following EA at Neiguan （PC 6）, the cerebral blood flow in the ischemic hippocampal CA1 region was significantly elevated, the number and microvascular integrated absorbance of the GLUTl-positive cells were significantly increased, nerve cell damage was ameliorated, and GLUT1 protein expression in the ischemic hippocampus was significantly increased. Results demonstrate that EA increased the cerebral blood flow of the hippocampal CA1 region and improved the glucose transport function, thereby attenuating neuronal injuries.