Blood Flowmeter Research Articles

Clinical evaluation of greater palatine artery hemodynamics in Le Fort I osteotomy

ObjectiveLe Fort I osteotomy (LIO) is a widely known standard orthognathic surgical treatment. However, complications such as osteonecrosis of the jaw due to poor postoperative blood flow to tissues of the maxilla have been reported. This study measured the hemodynamics of the greater palatine artery (GPA) in patients who underwent LIO to explore the factors that affect postoperative blood flow. MethodsWe included 15 patients who underwent LIO and sagittal split ramus osteotomy (SSRO), and 8 patients, who only underwent SSRO, were included as controls. Preoperative, intraoperative, and postoperative blood flow in the oral mucosa anterior to the foramen magnum was measured with a laser Doppler blood flow meter. ResultsOn average blood flow at immediately after downfracture in LIO patients reduced to 24.8% of baseline blood flow and patients who underwent anterior maxillary movement had a lower recovery rate at any time. Multiple regression analysis showed that the greater the maxillary anterior shift and the longer the time from maxillary disarticulation to fixation (mandibular fracture time: DFT), the more delayed was the blood flow recovery. ConclusionsSince blood flow decreased after downfracture and recovered only to around 85.4% of baseline after 6 months in LⅠO, preserving blood vessels is important. Furthermore, the recovery rate was lower in patients who underwent anterior movement, and blood flow reduced more in patients with longer DFT, suggesting the importance of determining the direction and distance of movement preoperatively, and repositioning and fixing the maxilla as quickly as possible during surgery.

Application of free forearm flap in reconstruction of postoperative defect of external nasal malignant tumor

Objective:To investigate the therapeutic effect of free forearm flaps in repairing the postoperative defect of external nasal malignant tumor. Methods:Six patients with nasal malignant tumor were treated with radical operation of external nasal malignant tumor and simultaneous reconstruction of external nasal defects with free forearm flap. Preoperative Allen experiment, ultrasonic Doppler blood flow meter or CT angiography confirmed that the forearm blood vessels were in good condition. Results:The free forearm flaps were obtained from six patients, and completely survived. During the follow-up period of 6-12months, all patients had good external nasal morphology, good nasal function, no nasal obstruction and anterior nostril stenosis, no obvious complications in donor hand and no local cancer recurrence. Conclusion:The free forearm flap is a reliable method to reconstruction the postoperative defect of external nasal malignant tumor, with a high success rate and good recovery of morphology and function recovery.

New rat model of spinal cord infarction with long-lasting functional disabilities generated by intraspinal injection of endothelin-1

BackgroundThe current method for generating an animal model of spinal cord (SC) infarction is highly invasive and permits only short-term observation, typically limited to 28 days.ObjectiveWe aimed to establish a...

Microcirculatory visualization and metabolomics of Dalbergia cochinchinensis in ameliorating coronary microvascular dysfunction in rats

This study employed microcirculation visualization and metabolomics methods to explore the effect and possible mechanism of Dalbergia cochinchinensis in ameliorating coronary microvascular dysfunction(CMD) induced by microsphere embolization in rats. Sixty SPF-grade male SD rats were randomized into sham, model, and low-, medium-, and high-dose [1.5, 3.0, and 6.0 g·kg~(-1)·d~(-1), respectively] D. cochinchinensis water extract groups. The rats in sham and model groups were administrated with equal volume of normal saline by gavage once a day for 7 consecutive days. The rat model of CMD was prepared by injecting polyethylene microspheres into the left ventricle, while the sham group was injected with an equal amount of normal saline. A blood flow meter was used to measure blood flow, and a blood rheometer to measure blood viscosity and fibrinogen content. An automatic biochemical analyzer and reagent kits were used to measure the serum levels of myocardial enzymes, glucose, and nitric oxide(NO). Hematoxylin-eosin(HE) staining was used to observe the pathological changes of myocardial tissue. DiI C12/C18 perfusion was used to infuse coronary microvessels, and the structural and morphological changes were observed using a confocal laser scanning microscope. AngioTool was used to analyze the vascular area, density, radius, and mean E lacunarity in the microsphere embolization area, and vascular blood flow resistance was calculated based on Poiseuille's law. Non-targeted metabolomics based on high performance liquid chromatography-quadrupole-time-of-flight mass spectrometry(UPLC-Q-TOF-MS) was employed screen potential biomarkers and differential metabolites regulated by D. cochinchinensis and the involved metabolic pathways were enriched. The pharmacodynamic results showed that compared with the model group, D. cochinchinensis significantly increased mean blood flow, reduced plasma fibrinogen content, lowered the levels of myocardial enzymes such as creatine kinase(CK), creatine kinase-MB(CK-MB), and lactate dehydrogenase(LDH), alleviate myocardial injury, and protect damaged myocardium. In addition, D. cochinchinensis significantly increased serum NO content, promoted vascular smooth muscle relaxation, dilated blood vessels, lowered serum glucose(GLU) level, improved myocardial energy metabolism, and alleviated pathological changes in myocardial fibrosis and inflammatory cell infiltration. The results of coronary microcirculation perfusion showed that D. cochinchinensis improved the vascular morphology, increased the vascular area, density, and radius, reduced vascular mean E lacunarity and blood flow resistance, and alleviated vascular endothelial damage in CMD rats. The results of metabolomics identified 45 differential metabolites between sham and model groups, and D. cochinchinensis recovered the levels 25 differential metabolites, which were involved in 8 pathways including arachidonic acid metabolism, arginine biosynthesis, and sphingolipids metabolism. D. cochinchinensis can ameliorate coronary microcirculation dysfunction caused by microsphere embolization in rats, and it may alleviate the pathological changes of CMD rats by regulating inflammatory reaction, endothelial damage, and phospholipid metabolism.

Novel wireless laser doppler flowmeter-based investigation of earlobe vascular dynamics in cardiopulmonary exercise testing.

[Purpose] A new wireless laser Doppler blood flowmeter has facilitated easier, more stable measurement of skin perfusion during exercise. However, earlobe blood flow during the cardiopulmonary exercise test remains unascertained. This study aimed to clarify the characteristics of earlobe blood flow during incremental exercise load in healthy individuals. [Participants and Methods] Among 25 healthy males (age 23.6 ± 2.5 years), cycle ergometer-based symptom-limited cardiopulmonary exercise test, after 4 minutes of rest, was conducted with a 4-minute 20W warm-up and a continuous 2W-increase in the work rate every 6 seconds; earlobe blood flow was measured using a wireless laser Doppler blood flowmeter. [Results] Compared with that at rest, earlobe blood flow increased significantly from 50% of exercise peak intensity to a maximum of 1.7 times, but decreased immediately after exercise. The earlobe blood flow %change did not significantly correlate with hemodynamic parameters and its inflection point 36.4% Loadpeak was significantly lower than the anaerobic metabolic threshold 58.1% Loadpeak. [Conclusion] In healthy participants, earlobe blood flow during cardiopulmonary exercise test increased gradually with low-intensity exercise from approximately 1.5 times the resting rate and approached the anaerobic metabolic threshold with a maximum of 1.7 times the resting earlobe blood flow, but decreased quickly after exercise.

Novel wireless laser doppler flowmeter-based investigation of earlobe vascular dynamics in cardiopulmonary exercise testing.

[Purpose] A new wireless laser Doppler blood flowmeter has facilitated easier, more stable measurement of skin perfusion during exercise. However, earlobe blood flow during the cardiopulmonary exercise test remains unascertained. This study aimed to clarify the characteristics of earlobe blood flow during incremental exercise load in healthy individuals. [Participants and Methods] Among 25 healthy males (age 23.6 ± 2.5 years), cycle ergometer-based symptom-limited cardiopulmonary exercise test, after 4 minutes of rest, was conducted with a 4-minute 20W warm-up and a continuous 2W-increase in the work rate every 6 seconds; earlobe blood flow was measured using a wireless laser Doppler blood flowmeter. [Results] Compared with that at rest, earlobe blood flow increased significantly from 50% of exercise peak intensity to a maximum of 1.7 times, but decreased immediately after exercise. The earlobe blood flow %change did not significantly correlate with hemodynamic parameters and its inflection point 36.4% Loadpeak was significantly lower than the anaerobic metabolic threshold 58.1% Loadpeak. [Conclusion] In healthy participants, earlobe blood flow during cardiopulmonary exercise test increased gradually with low-intensity exercise from approximately 1.5 times the resting rate and approached the anaerobic metabolic threshold with a maximum of 1.7 times the resting earlobe blood flow, but decreased quickly after exercise.

The cardiovascular mononeuropathy in Hemodialysis Patients analysed by a combination with reactivity tests to noninvasively evaluate skin sympathetic nerve activity and skin microvascular function by (LDF)

Aim: Although several patients with kidney disease have simultaneous dysfunction of the parasympathetic and sympathetic nervous systems, orthostatic hypotension during a hemodialysis (HD) procedure impacts not only the form of treatment but overall comfort of life for patients with HD. Despite a number of methods that are not invasive and have already been used to assess autonomous functioning, a system for monitoring malfunction throughout filtration of blood therapy which has yet to be discovered. Methods: Regarding the purpose of monitoring the autonomous function of stable 40 regular HD patients and 35 healthy controls, we examined the clinical application of the laser-Doppler blood flow meter (LDF). By detecting the periflux blood flow decreasing velocity (PDV) while combined with the Valsalva manoeuvre, the LDF device which was used for an autonomous test. We also looked at the relationship between PDV and traditional atherosclerosis testing. Results: The baseline PDV (5.30 ± 2.93), comparative to subjects who were in excellent condition (9.65 ± 7.10), was substantially decreased in the HD populace. Furthermore, we discovered a substantial connection between PDV and established parameters like heart rate fluctuation and ankle-brachial blood pressure indexing. Conclusion: Regarding assessing autonomous functioning in hemodialysis patients, evaluation of PDV by LDF is just as effective as the standard approach. The benefit from regular and recurring assessments of autonomous dysfunction is made possible by the device's ease.

Usefulness of a Novel Vascular Access Management Method Using a Laser Blood Flowmeter

Introduction: Various methods for vascular access (VA) management have been studied. We investigated the usefulness of a new, simple, and quantitative VA management method using the Pocket LDF® laser blood flowmeter (hereinafter “LDF”) that noninvasively measures peripheral circulation flow. Methods: Peripheral circulation flow was measured in 82 patients (43 men) on maintenance hemodialysis with an arteriovenous fistula (AVF). The shunt symmetry index (SSI) was calculated as peripheral circulation flow in the AVF limb divided by that in the non-AVF limb. SSI was used for microcirculation evaluation and also compared by AVF site. Patients undergoing vascular access interventional therapy (VAIVT) underwent ultrasound evaluation (Doppler ultrasonography) of the AVF and SSI measurement before and after VAIVT. SSI was compared between those who did and did not require VAIVT, and the cutoff value for SSI was determined by receiver operating characteristic curve (ROC) analysis. Results: As many as 86% of the patients who were measured peripheral circulation flow had SSI <1.0, which indicates that AVF reduced peripheral circulation flow. All patients who underwent VAIVT showed a decrease in SSI to <1.0 after VAIVT, probably due to improvement of stenosis. SSI differed significantly between patients who did and did not require VAIVT (1.20 ± 0.49 vs. 0.65 ± 0.33, p < 0.001), which indicates that SSI is affected by the presence of stenosis in the proximal vein of the VA anastomosis. In patients with SSI ≥1.0, stenosis of the proximal vein of the AVF caused stasis of blood flow, resulting in increased peripheral blood flow. AVF site seems to have no impact on peripheral circulation flow. The SSI cutoff value for the screening of proximal vein stenosis was 1.06 (sensitivity: 0.69, specificity: 0.93, area under the curve: 0.81). Conclusion: Based on the ROC analysis, we recommend considering AVF ultrasound for SSI >1.06. Our results suggest the usefulness of the described VA management method using the LDF.

Development of a Non-Invasive Local Heating Load Test to Detect Severe Limb Ischemia Within 200seconds.

To establish a non-invasive test method for the rapid detection of severe ischemia (SI) in the limbs in patients with peripheral arterial disease (PAD). Between November 2019 and May 2021, 22 patients admitted for PAD to 2 hospitals agreed to participate in the study. All patients underwent a local heating load (LHL) test. SI was defined as at least 1 ankle-brachial index value of <.4 and/or transcutaneous oximetry value of <30mmHg. The other cases were classified as mild-to-moderate ischemia (MMI). The LHL test was performed simultaneously with 15minutes of heating and measurement by attaching a blood flow meter measuring probe combined with a warmer to the patient's dorsal foot. Evaluation consisted of 200-s periods from the start of heating to 800seconds. For each period, perfusion value (PV) was evaluated, and slope was calculated graphically based on linear regression as PV fluctuation per minute. Test accuracy was calculated using a receiver operating characteristic curve. Twenty-four limbs of 18 patients were finally evaluated; 4 patients (2 with missing data, 1 with collagen disease, and 1 with embolism) were excluded, with 13 and 11 limbs in the SI and MMI groups, respectively. The SI group showed a significantly lower slope value in the first 200seconds and lower PV at 200seconds and thereafter. From the slope value, it was possible to detect SI with 85% sensitivity and 73% specificity at 200seconds. PV could be determined with higher accuracy in periods after 200seconds, with 85% sensitivity and 82% specificity at 800seconds. Our non-invasive LHL test could be used as a rapid screening test to detect SI in limbs within 200seconds, as well as a more accurate test to detect ischemia within 800seconds.

Proteomics on the role of muscone in the “consciousness-restoring resuscitation” effect of musk on ischemic stroke

Ethnopharmacological relevanceMusk is a representative drug of aroma-relieving traditional Chinese medicine, and it is a commonly used traditional Chinese medicine for the treatment of ischemic stroke. Muscone is the core medicinal component of musk. Aim of the studyWe sought to identify the target of muscone in the treatment of ischemic stroke using network pharmacology, an animal model of ischemic stroke, and differential proteomics. Materials and methodsThe drug targets of muscone in the treatment of ischemic stroke were predicted and analyzed using information derived from sources such as the Traditional Chinese Medicine Systems Pharmacology database and Swiss Target Prediction tool. The animal model of focal cerebral ischemia was established by suture-based occlusion of the middle cerebral artery of rats. The rats were divided into six groups: sham-operated control, model, musk, muscone1, muscone2, and muscone3. Neurological deficit scores were calculated after intragastric administration of musk or muscone. The microcirculation blood flow of the pia mater was detected using a laser speckle blood flow meter. The cerebral infarction rate was detected by 2,3,5-triphenyltetrazolium chloride staining. The necrosis rate of the cerebral cortex and the hippocampal neurons was detected by hematoxylin and eosin staining. Blood-brain barrier damage was detected by the Evans blue method. Quantitative proteomics analysis in the sham-operated control, model, and muscone groups was performed using tandem-mass-tags. Considering fold changes exceeding 1.2 as differential protein expression, the quantitative values were compared among groups by analysis of variance. Furthermore, a protein-protein interaction network was constructed, and differentially expressed proteins were analyzed by gene ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. ResultsNetwork pharmacology identified 339 targets for the intersection of 17 components of musk and cerebral ischemia-reperfusion injury. The GO and KEGG enrichment items mainly identified regulation of neuronal synaptic structure and transfer function, synaptic neurotransmitters, and receptor activity. Zoopery showed that the model group had a higher behavioral score, cerebral infarction rate, cortical and hippocampal neuron death rate, Evans blue exudation in the brain, and bilateral pia mater microcirculation blood flow differences than the sham-operated control group (P <0.01). Compared with the model group, the behavioral score, infarction rate, hippocampal neuronal mortality, and Evans blue content decreased significantly in the musk, muscone2, and muscone3 groups (P <0.05). Proteomic analysis showed that 160 genes were differentially expressed among the sham-operated control, model, and muscone groups. GO items with high enrichment included neuronal synapses, postsynaptic signal transduction, etc. KEGG items with high enrichment included cholinergic synapses, calcium signaling pathway, dopaminergic synapses, etc. Protein interaction analysis revealed that the top three protein pairs were Ndufa10/Ndufa6, Kcna2/Kcnab2, and Gsk3b/Traf6. ConclusionsMuscone can reduce neuronal necrosis, protect the blood-brain barrier, and improve the neurological damage caused by cerebral ischemia via molecular mechanisms mainly involving the regulation of neuronal synaptic connections. Muscone is an important active component responsible for the “consciousness-restoring resuscitation” effect of musk on ischemic stroke.

The effect of glucagon on local subcutaneous blood flow in non-diabetic volunteers; a proof-of-concept study

IntroductionGlucagon and insulin are the two most important hormones in glucose metabolism and have been incorporated in the dual-hormonal artificial pancreas, a device for automated glucose regulation for people with diabetes type 1. Currently the subcutis is the preferred site of hormone delivery for insulin-only as well as dual-hormonal artificial pancreas systems. The delay in glucose-lowering effect after subcutaneous injection of insulin is substantial, in contrast to the elevation of blood glucose values after subcutaneously injected glucagon which is occurs shortly after injection. We hypothesize that this is caused by properties of glucagon and have investigated the vasodilative effect of glucagon on subcutaneous blood flow in this proof-of-concept study. MethodsTwenty-two volunteers received subcutaneous injections of 0.1 mg and 0.01 mg glucagon, and saline on the abdomen. Blood flow was measured by a laser doppler blood flowmeter for 35 min after injections. ResultsInjection of 0.1 mg glucagon resulted in a significant increase in blood flow compared with baseline blood flow for all time intervals. Significant increase was also observed after the 0.01 mg glucagon injection, except between two- and five-min post injection. The inter-individual variance was large and a third of the subjects did not show an apparent increase in local subcutaneous blood flow after the 0.1 mg glucagon injection. ConclusionThis proof-of-concept study shows that micro-boluses of glucagon increases local subcutaneous blood flow on the abdomen of non-diabetic subjects. However, the vasodilative effect of glucagon is not observed in all subjects. The trial was not registered to protect intellectual property rights.

Effects of enriched environment on microglia and functional white matter recovery in rats with post stroke cognitive impairment

BackgroundWhite matter damage is an important contributor to cognitive impairment after stroke. This study was designed to explore the beneficial effects of enriched environment (EE) on white matter recovery and cognitive dysfunction after stroke, and further explore the potential mechanism of EE on white matter recovery from the perspective of microglia and microglia-mediated neuroinflammation. MethodsMale SD rats underwent middle cerebral artery occlusion (MCAO) or sham surgery. During the MCAO operation, a laser Doppler blood flow meter was used to monitor the blood flow to ensure the success of the model. At 72 h after the operation, 3 rats were selected for TTC staining to identify the infarct size. One week after surgery, the rats were randomly assigned into four different groups—MCAO+standard environment (SE), MCAO+enriched environment (EE), Sham+SE and Sham+EE for 4 weeks. At four weeks after MCAO surgery, neurological function deficiency condition and cognitive function were assessed using Longa score and Morris Water Maze prior to euthanasia. The loss or regeneration of myelin was stained with LFB, the expression of myelin regeneration-related protein and microglia protein was quantified by western blot and immunofluorescence, and the level of inflammatory factors was measured by ELISA. ResultsEE treatment remarkably decreased the neurological deficit score, ameliorated the cognitive functional deficit in MCAO rats. Furthermore, EE alleviated white matter lesions and demyelination, increased myelin basic protein expression and decreased the number of activated microglia in the hippocampus of MCAO rats. In addition, ELISA analysis indicated that EE decreased the level of IL-1β, IL-6, which further suggests that EE may reduce the level of pro-inflammatory factors by affecting the expression of microglia marker, IBA1, provide a benefit physiological environment for myelin recovery, and improve post stroke cognitive impairment. ConclusionsOur results suggest that exposure to EE substantially reduced the damage to brain tissue caused by activation of microglia activation, decreased the level of pro-inflammatory cytokins, which may induced by microglia, protected and promote white matter recovery to improve cognitive function after stroke. Our findings also indicate exposure to EE is beneficial for patients with white matter impairment characterised by white matter disease-related inflammation.

Effects of Footcare-programs Intervention using Thermography and Blood Flow Meters on the Self-care Ability of Patients with Type 2 Diabetes

目的：2型糖尿病患者を対象にサーモグラフィや血流計を用いたフットケアプログラムを実施し，血管障害の理解やフットケア行動，セルフケア能力の介入効果を検討した．

Prediction of Cross-Clamp-Induced Cerebral Ischemia During Carotid Endarterectomy Using Arterial Blood Flow Assessment

BackgroundCross-clamping during carotid endarterectomy (CEA) is associated with the risk of cerebral ischemia. Various studies have evaluated different criteria for detecting cerebral ischemia, but difficulties arise when ischemic changes appear after the carotid artery is cross-clamped and incised. Here, we explored a parameter that can predict cerebral ischemia prior to cross-clamping during CEA using a blood-flow meter. MethodsThe carotid arterial blood flow was measured directly (direct ABF) in the common carotid artery prior to cross-clamping. The anatomical information in preoperative magnetic resonance imaging, cerebral blood flow in xenon-enhanced computed tomography, and carotid peak systolic flow velocity by carotid echo from the skin surface were also evaluated. A decrease in the short-latency somatosensory evoked potentials (SSEP) during cross-clamping to insert a shunt was assessed, and a decrease in amplitude of ≥ 50% was considered an indicator for cerebral ischemia. Surgery was performed under general anesthesia, and a shunt was inserted in all cases. ResultsOf 156 CEA patients between April 2013 and March 2020, 30 had decreased SSEP during cross-clamping. The baseline characteristics and intra- and postoperative findings were not significantly different between patients with and without a decrease in SSEP. Among the evaluated parameters, only the direct-ABF ratio (ABF-internal carotid artery/ABF-common carotid artery) differed significantly between the 2 groups (P = 0.011). The direct-ABF ratio ≤ 0.58 was predictive of cerebral ischemia during CEA. ConclusionsDirect-ABF measurement with an ultrasonic blood-flow meter can be useful for predicting cerebral ischemia prior to carotid artery cross-clamping during CEA.

A Pulsed Wave Doppler Ultrasound Blood Flowmeter by PMUTs

This letter describes a blood flowmeter by the pulsed wave Doppler (PWD) ultrasound detection procedure utilizing piezoelectric micromachined ultrasonic transducers (pMUTs) with the aluminum nitride (AlN) film as the piezoelectric material. The transceiver electronics for the PWD scheme are constructed for system control and signal processing, and a blood-mimicking fluid (BMF) is synthesized for flow velocity tests. Both the average Doppler frequency-shift and Doppler power spectrum density (PSD) shift with respect to the flow velocity have been characterized and validated, and the flow direction can also be recognized. Finally, a real-time pulsatile flow measurement is demonstrated to emulate the feasibility of monitoring blood flows in practice. [2021-0077]

Gingival blood flow before, during, and after clenching, measured by laser Doppler blood flowmeter: A pilot study

This study aimed to investigate the effects of the strong occlusal force on the hemodynamics of gingival microcirculation. Eleven adult volunteers with healthy periodontium and normal occlusion participated in this study. Using a noncontact laser Doppler flowmeter placed at the attached gingiva and the interdental papilla of the maxillary first premolar, changes in gingival blood flow (GBF) were examined during and after clenching. When the strong occlusal pressure was applied on the maxillary first premolar by clenching, GBF in the attached gingiva on the buccal side decreased significantly compared with the resting GBF, with medians of 2.3mL/min/100g and 5.4mL/min/100g, respectively (P<0.05). After the release of the maximum clenching, GBF recovered immediately and transiently increased to a median of 2.4mL/min/100g, showing a significant difference to the resting GBF (P<0.05). In contrast, in the interdental papilla, no significant change in GBF was found by clenching. Ischemia of the buccal attached gingiva associated with strong clenching may be due to compression of the vascular network of the periodontal membrane. Through reactive hyperemia resulting from the release of clenching, it is possible not only that blood flow will be restored to the tissue but that the tissue itself may be damaged by the reperfusion. During active orthodontic treatment, it is suggested that occlusal management to prevent occlusal trauma is important to avoid detrimental effects on periodontal tissues.

Ginsenoside Rg1 attenuates cerebral ischemia-reperfusion injury due to inhibition of NOX2-mediated calcium homeostasis dysregulation in mice

BackgroundThe incidence of ischemic cerebrovascular disease is increasing in recent years and has been one of the leading causes of neurological dysfunction and death. Ginsenoside Rg1 has been found to protect against neuronal damage in many neurodegenerative diseases. However, the effect and mechanism by which Rg1 protects against cerebral ischemia-reperfusion injury (CIRI) are not fully understood. Here, we report the neuroprotective effects of Rg1 treatment on CIRI and its possible mechanisms in mice. MethodsA bilateral common carotid artery ligation was used to establish a chronic CIRI model in mice. HT22 cells were treated with Rg1 after OGD/R to study its effect on [Ca2+]i. The open-field test and pole-climbing experiment were used to detect behavioral injury. The laser speckle blood flowmeter was used to measure brain blood flow. The Nissl and H&E staining were used to examine the neuronal damage. The Western blotting was used to examine MAP2, PSD95, Tau, p-Tau, NOX2, PLC, p-PLC, CN, NFAT1, and NLRP1 expression. Calcium imaging was used to test the level of [Ca2+]i. ResultsRg1 treatment significantly improved cerebral blood flow, locomotion, and limb coordination, reduced ROS production, increased MAP2 and PSD95 expression, and decreased p-Tau, NOX2, p-PLC, CN, NFAT1, and NLRP1 expression. Calcium imaging results showed that Rg1 could inhibit calcium overload and resist the imbalance of calcium homeostasis after OGD/R in HT22 cells. ConclusionRg1 plays a neuroprotective role in attenuating CIRI by inhibiting oxidative stress, calcium overload, and neuroinflammation.

Ultrasonic blood flowmeter with a novel Xero algorithm for a mechanical circulatory support system

Mechanical circulatory support systems (MCSSs) are crucial devices for transplants in patients with heart failure. The blood flowing through the MCSS can be recirculated or even stagnated in the event of critical blood flow issues. To avoid emergencies due to abnormal changes in the flow, continuous changes of the flowrate should be measured with high accuracy and robustness. For better flowrate measurements, a more advanced ultrasonic blood flowmeter (UFM), which is a noninvasive measurement tool, is needed. In this paper, we propose a novel UFM sensor module using a novel algorithm (Xero) that can exploit the advantages of both conventional cross-correlation (Xcorr) and zero-crossing (Zero) algorithms, using only the zero-crossing-based algorithm. To ensure the capability of our own developed and optimized ultrasonic sensor module for MCSSs, the accuracy, robustness, and continuous monitoring performance of the proposed algorithm were compared to those of conventional algorithms after application to the developed sensor module. The results show that Xero is superior to other algorithms for flowrate measurements under different environments and offers an error rate of at least 0.92%, higher robustness for changing fluid temperatures than conventional algorithms, and sensitive responses to sudden changes in flowrates. Thus, the proposed UFM system with Xero has a great potential for flowrate measurements in MCSSs.

Reversal of Aging‐Associated Vasoreparative Dysfunction and Myelopoietic Bias in Bone Marrow Stem/Progenitor Cells by Angiotensin‐(1‐7)

Aging increases risk for ischemic vascular diseases. Bone marrow-derived hematopoietic stem/progenitor cells (HSPCs) are known to stimulate vascular regeneration. However, aging impairs vasoreparative functions and myelopoietic bias in HSPCs. The alternative axis of renin-angiotensin system, angiotensin converting enzyme-2 (ACE2)/ angiotensin-(1-7) (Ang-(1-7)/Mas receptor (MasR), is vasoprotective in contrast to the canonical pathway ACE/Ang II/AT1 receptor. This study tested if MasR activation by Ang-(1-7) restores vasoreparative functions in HSPCs derived from aging mice. Lin-Sca-1+cKit+ (LSK) cells were isolated from Young (3-5 months) (n=10) or Old (20-22 months) (n=10) mice, and migration and proliferation were evaluated. Old mice were treated with Ang-(1-7) (1 µg/Kg/min, four weeks). Hindlimb ischemia was induced by femoral ligation, and mobilization of LSK cells into the blood circulation was determined. Blood flow recovery was monitored by Laser Doppler blood flow meter and vascular density was evaluated by immunohistochemistry for CD31 and isolectin B4-positive structures. Myeloid cells in bone marrow were evaluated by colony forming unit (CFU) assay for granulocyte-macrophage differentiation, followed by flow cytometry of monocyte (Ly6G-CD11b+Ly6Chi) and macrophage (Ly6G-CD11b+F4/80+Ly6Chi) populations. Pro-myelopoietic factors, S100A8/A9, in the bone marrow supernatant were probed by western blotting. Old mice have decreased number of LSK cells in the circulation with reduced migration or proliferation in response to stromal-derived factor-1α, compared to Young (n=6). These dysfunctions were reversed by Ang-(1-7). Ischemia increased the number of circulating LSK cells in Young mice and restored blood flow to ischemic areas (n=6). These responses were impaired in Old mice but were restored by treatment with Ang-(1-7) (n=6). Neovascularization of ischemic areas is reduced in old mice compared to the Young and was restored by Ang-(1-7) (n=4). CFU assay revealed that myelopoiesis is upregulated in the Old bone marrow (increased differentiation into monocyte-macrophage populations) with increased levels of S100A8/A9, compared to the Young. Treatment of Old mice with Ang-(1-7), decreased myelopoietic differentiation and S100A8/A9 concentration to similar levels as in Young (n=4). These results suggest that activation of MasR would be a promising approach for enhancing vasoreparative potential of stem/progenitor cells in aging.

A non-invasive heart rate measurement system using laser Doppler blood flowmetry with husbandry training of the masked palm civet (Parguma larvata)

Husbandry training (HT) is done to facilitate healthcare, treatment or animal research with zoo animals. At the Omuta City Zoo, HT of masked palm civets (Parguma larvata) is used to aid the taking of blood samples. With HT the burden on the animal can be remarkably reduced without the use of anesthesia. However, it is necessary to devise a blood sampling method using HT that reduces stress on the animals as much as possible. To devise such a stress-reducing method, quantitative assessments related to stress are needed. As heart rate increases with stress, we attempted to devise a non-invasive method for measuring heart rate. The attachment of sensors not only stresses the animal but also requires much effort from keepers. Therefore, a laser Doppler blood flowmeter (LDF) was embedded in the HT board, and an LDF and an algorithm to eliminate body motion artifacts were used in measurement attempts. As a result, a clear pulse wave was detected in some sections, and heart rate was calculated from the pulse wave.