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1.
Artigo em Russo | MEDLINE | ID: mdl-38639147

RESUMO

OBJECTIVE: To study the dynamics of hemorheologic changes and the frequency of early complications of laparoscopic radical hysterectomy in patients with uterine corpus cancer depending on conducting rehabilitation activities in the early postoperative period. MATERIAL AND METHODS: The number of patients with uterine corpus cancer equal 49 (mean age 54.8±2.2 years), divided into 2 comparable groups, was examined: experimental group - 23 patients, who received local magnetotherapy since the first day after surgery for 5-6 days, and control group - 26 patients without physiotherapy. Comparative group included 24 healthy women. The basic rheological parameters, namely blood viscosity at high and low shear rate, hematocrit, erythrocytes' aggregation and deformability, erythrocytes and platelets electrophoretic mobility, were evaluated in all patients initially, on the 1st and 5th days after surgery and in comparison group. RESULTS: There were changes in the rheological properties of the blood before surgery in patients of both groups: increase of blood viscosity, enhancement of aggregation activity of its formed elements, decrease of erythrocytes' deformability properties. The laparoscopic radical hysterectomy was accompanied by the exacerbation of these disorders. The early magnetotherapy in patients reduced hemorheological abnormalities up to the preoperative parameters (p<0.05) for 5 days, as well as reduced the incidence of early postoperative complications by 2.4 times compared to the control group. CONCLUSION: The application of local low-frequency low-intensity magnetotherapy since the first postoperative day allows to reduce the level of postoperative hemorheological abnormalities up to the level of preoperative parameters, as well as the frequency of early postoperative complications.


Assuntos
Neoplasias , Humanos , Feminino , Pessoa de Meia-Idade , Hemorreologia , Deformação Eritrocítica , Agregação Eritrocítica , Complicações Pós-Operatórias
2.
Sci Rep ; 14(1): 4260, 2024 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-38383860

RESUMO

Multiple myeloma (MM) is considered to be one of the hematological malignancies formed by excessive and abnormal proliferation of plasmocytes. Among other parameters, several blood tests are used to diagnose multiple myeloma. The hemorheological profile in multiple myeloma is not widely studied. Hemorheology includes the study of measuring the deformability and aggregation of erythrocytes, blood viscosity, and sedimentation rate. The degree of deformability of blood cells is necessary to maintain proper vital functions. Proper deformability of red blood cells ensures proper blood circulation, tissue oxidation and carbon dioxide uptake. The aim of the study was to compare morphology and blood rheology parameters in patients with MM and healthy individuals. The study included 33 patients with MM, and 33 healthy subjects of the same age. The hematological blood parameters were evaluated using ABX MICROS 60 hematology analyzer. The LORCA Analyzer to study erythrocyte aggregation and deformability. Patients with MM had lower red blood cells count (RBC) (9.11%) (p < 0.001) and half time of total aggregation (T1/2) (94.29%) (p < 0.001) values and higher mean corpuscular volume (MCV) (5.50%) (p < 0.001), aggregation index (AI) (68.60%) (p < 0.001), total extent of aggregation (AMP) (87.92%) (p < 0.001) values than the healthy control group. Aggregation in patients with MM is different compared to healthy individuals. It was observed that the percentage of cell aggregation is almost 50% higher than in the control group. The study of morphology, aggregation and deformability of erythrocytes in patients with suspected MM may be helpful in making clinical decisions.


Assuntos
Deformação Eritrocítica , Mieloma Múltiplo , Humanos , Hemorreologia , Eritrócitos , Agregação Eritrocítica , Reologia , Viscosidade Sanguínea , Sedimentação Sanguínea
3.
Am J Physiol Heart Circ Physiol ; 326(3): H705-H714, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38241007

RESUMO

Pentoxifylline is a nonselective phosphodiesterase inhibitor used for the treatment of peripheral artery disease. Pentoxifylline acts through cyclic adenosine monophosphate, thereby enhancing red blood cell deformability, causing vasodilation and decreasing inflammation, and potentially stimulating ventilation. We conducted a double-blind, placebo-controlled, crossover, counter-balanced study to test the hypothesis that pentoxifylline could lower blood viscosity, enhance cerebral blood flow, and decrease pulmonary artery pressure in lowlanders following 11-14 days at 3,800 m. Participants (6 males/10 females; age, 27 ± 4 yr old) received either a placebo or 400 mg of pentoxifylline orally the night before and again 2 h before testing. We assessed arterial blood gases, venous hemorheology (blood viscosity, red blood cell deformability, and aggregation), and inflammation (TNF-α) in room air (end-tidal oxygen partial pressure, ∼52 mmHg). Global cerebral blood flow (gCBF), ventilation, and pulmonary artery systolic pressure (PASP) were measured in room air and again after 8-10 min of isocapnic hypoxia (end-tidal oxygen partial pressure, 40 mmHg). Pentoxifylline did not alter arterial blood gases, TNF-α, or hemorheology compared with placebo. Pentoxifylline did not affect gCBF or ventilation during room air or isocapnic hypoxia compared with placebo. However, in females, PASP was reduced with pentoxifylline during room air (placebo, 19 ± 3; pentoxifylline, 16 ± 3 mmHg; P = 0.021) and isocapnic hypoxia (placebo, 22 ± 5; pentoxifylline, 20 ± 4 mmHg; P = 0.029), but not in males. Acute pentoxifylline administration in lowlanders at 3,800 m had no impact on arterial blood gases, hemorheology, inflammation, gCBF, or ventilation. Unexpectedly, however, pentoxifylline reduced PASP in female participants, indicating a potential effect of sex on the pulmonary vascular responses to pentoxifylline.NEW & NOTEWORTHY We conducted a double-blind, placebo-controlled study on the rheological, cardiorespiratory and cerebrovascular effects of acute pentoxifylline in healthy lowlanders after 11-14 days at 3,800 m. Although red blood cell deformability was reduced and blood viscosity increased compared with low altitude, acute pentoxifylline administration had no impact on arterial blood gases, hemorheology, inflammation, cerebral blood flow, or ventilation. Pentoxifylline decreased pulmonary artery systolic pressure in female, but not male, participants.


Assuntos
Pentoxifilina , Masculino , Humanos , Feminino , Adulto Jovem , Adulto , Pentoxifilina/farmacologia , Pentoxifilina/uso terapêutico , Hemorreologia , Fator de Necrose Tumoral alfa , Hipóxia , Oxigênio , Aclimatação/fisiologia , Inflamação/complicações , Gases , Circulação Cerebrovascular , Altitude
4.
Zhongguo Zhong Yao Za Zhi ; 48(2): 292-299, 2023 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-36725218

RESUMO

Caused by endocrine disorder, hyperplasia of mammary glands(HMG) tends to occur in the young with increasing incidence, putting patients at the risk of cancer and threatening the health of women. Therefore, the prevention and treatment of HMG is attracting more and more attention. Amid the modernization of traditional Chinese medicine(TCM), many scholars have found that Chinese patent medicine has unique advantages and huge potential in treatment of endocrine disorder. Particularly, Chinese patent medicine with the function of blood-activating and mass-dissipating, such as Xiaojin Pills and Xiaozheng Pills, has been commonly used in clinical treatment of HMG, which features multiple targets, obvious efficacy, small side effect, and ease of taking and carrying around. Clinical studies have found that the combination of Chinese patent medicine with other medicine can not only improve the efficacy and relieve symptoms such as hyperplasia and pain but also reduce the toxic and side effects of western medicine. Therefore, based on precious pharmacological research and clinical research, this study reviewed the mechanisms of blood-activating mass-dissipating Chinese patent medicine alone and in combination with other medicine, such as regulating levels of in vivo hormones and receptors, promoting apoptosis, inhibiting angiogenesis, improving hemorheology indexes, enhancing immunity, and boosting antioxidant ability. In addition, limitations and problems were summarized. Thereby, this study is expected to lay a theoretical basis for the further study and clinical application of blood-activating mass-dissipating Chinese patent medicine alone or in combination with other medicine against HMG.


Assuntos
Medicamentos de Ervas Chinesas , Glândulas Mamárias Humanas , Humanos , Feminino , Hiperplasia/tratamento farmacológico , Medicamentos sem Prescrição , Glândulas Mamárias Humanas/patologia , Medicina Tradicional Chinesa , Hemorreologia , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico
5.
Zhen Ci Yan Jiu ; 47(1): 46-52, 2022 Jan 25.
Artigo em Chinês | MEDLINE | ID: mdl-35128870

RESUMO

OBJECTIVE: To observe the effect of electroacupuncture (EA) of "Biao-Ben acupoints" (Biao indicates pathogenic factors of disease; Ben refers to body constitution) on renal function, hemorheology and endothelial nitric oxide synthase (eNOS) level in patients with early diabetic kidney disease (DKD), so as to explore its mechanism underlying relieving early DKD. METHODS: A total of 120 patients with early DKD were selected and randomized into 3 groups: medication, conventional acupoints, and "Biao-Ben"acupoints groups by stratified randomization method, with 40 cases in each group. Patients of the me-dication group were treated by routine symptomatic supportive treatment (gleziquantel tablets or subcutaneous injection of insulin \[for hyperglycemia\], candesartan tablet \[hypertension\], simvastatin tablets \[hyperlipidemia\], etc.).Based on the medication group, patients of the conventional acupoint group were treated by EA of bilateral Feishu (BL13), Weiwanxiashu (EX-B3), Weishu (BL21), Shenshu (BL23), Sanyinjiao (SP6), Taixi (KI3) (main acupoints), etc., and those of the Biao-Ben acupoint group treated by EA of main acupoints Zhongwan (CV12), Fenglong (ST40), Xuehai (SP10) and Taichong (LR3) (Biao acupoints), and Guanyuan (CV4) and Zusanli (ST36) (Ben acupoints). The EA treatment was conducted one daily, 5 days a week for 8 weeks. The urine microprotein level in 24 h was detected using an automatic specific protein analyzer, followed by calcula-ting the urine albumin excretion rate (UAER). The serum creatinine (Scr), urea nitrogen (BUN) and cystatin (CysC) contents were detected by using an automatic biochemical analyzer, and the whole blood low-cut viscosity (ηbL), whole blood mid-cut viscosity (ηbM), whole blood high-cut viscosity (ηbH), plasma viscosity (ηp) and fibrinogen (FIB) levels were detected using an automatic hemorheology tester, and the serum eNOS and nitric oxide (NO) levels assayed using enzyme linked immunosorbent assay. The total clinical effective rates were compared and the adverse reactions of the treatment were recorded. RESULTS: Compared with the values before the treatment in each group, the levels of UAER, Scr, BUN, CysC, ηbL, ηbM, ηbH, ηp and FIB were all significantly decreased (P<0.01), while serum eNOS and NO levels significantly increased in the three groups after the treatment (P<0.01). Compared with the medication group, the levels of UAER, Scr, BUN, CysC, ηbL, ηbM, ηbH, ηp and FIB were notably lower (P<0.01, P<0.05), and serum eNOS and NO contents obviously higher in both the conventional acupoint and "Biao-Ben" acupoint groups (P<0.01). Comparison between the two EA groups showed that the levels of UAER, BUN, ηbL, ηbM, ηbH and ηp were lower (P<0.05), whereas the serum eNOS and NO contents were considerably higher (P<0.05) in the "Biao-Ben" acupoint group than in the conventional acupoint group. After the treatment, the total clinical effective rate of the "Biao-Ben" acupoint group was 89.74%(35/39), being significantly higher than those of both the conventional acupoint group (71.05%, 27/38,P<0.05) and medication group (64.10%, 25/39, P<0.05). CONCLUSION: EA of "Biao-Ben" acupoints can improve renal function and reduce microcirculation disorders in patients with early DKD, which may be related to its function in up-regulating the levels of serum eNOS and NO.


Assuntos
Diabetes Mellitus , Nefropatias Diabéticas , Eletroacupuntura , Pontos de Acupuntura , Nefropatias Diabéticas/terapia , Hemorreologia , Humanos , Rim/fisiologia , Óxido Nítrico Sintase Tipo III
6.
Comput Math Methods Med ; 2021: 6268856, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34697555

RESUMO

The motive of this article is to present the case study of patients to investigate the association between the ultrasonographic findings of lower extremity vascular disease (LEAD) and plaque formation. Secondly, to examine the association between the formation of coronary artery and carotid artery atherosclerosis in patients with type 2 diabetes mellitus. 124 patients with type 2 diabetes (64 males and 60 females with the age group 25-78 years) are considered for the research studies who have registered themselves in the Department of Endocrinology and Metabolism from April 2017 to February 2019. All participants have reported their clinical information regarding diabetes, alcohol consumption, smoking status, and medication. The blood samples from subjects are collected for measurement of HbA1c, total cholesterol, triglycerides, HDL-c, and LDL-c levels. Two-dimensional ultrasound has been used to measure the inner diameter, peak flow velocity, blood flow, and spectral width of the femoral artery, pop artery, anterior iliac artery, posterior tibial artery, and dorsal artery and to calculate the artery stenosis degree. Independent factors of atherosclerosis are determined by multivariate logistic regression analysis. The results are evaluated within the control group and it is found that there is no significant impact of gender, age, and body mass index (P > 0.05) on the lower extremity vascular diseases. Those with smoking, alcohol consumption, hypertension, and dyslipidemia have higher positive rate (P < 0.05). The type 2 diabetes mellitus group has higher diastolic blood pressure and lower triglyceride (P < 0.05). Diastolic blood pressure, HbA1C, total cholesterol, HDL-c, and LDL-C are not remarkably dissimilar between the type 2 diabetes mellitus group and the control group (P > 0.05). Compared with the control group, the type 2 diabetes mellitus group has higher frequency of lower extremity vascular diseases in the dorsal artery than in the pop artery (P < 0.05). The blood flow of type 2 diabetes mellitus group is found to be lower than that of the control group, especially in the dorsal artery (P < 0.05). The blood flow velocity of the dorsal artery is accelerated (P < 0.01). Among 117 patients of type 2 diabetes mellitus (94.35%) with a certain degree of injury, there are 72 cases of type I carotid stenosis (58.06%), 30 cases of type II carotid stenosis (24.19%), and 15 cases of type III carotid stenosis (12.10%). Out of 108 subjects in the control group, there are 84 cases of type 0 carotid stenosis (77.78%), 19 cases of type I carotid stenosis (17.59%), 5 cases of type II carotid stenosis (4.63%), and 0 case of type III carotid stenosis (0.00%). Compared with the control group, carotid stenosis is more common in patients with type 2 diabetes mellitus (P < 0.05). Age, smoking, duration of diseases, systolic blood pressure, and degree of carotid stenosis are found to be associated with atherosclerosis. The findings suggest that the color Doppler ultrasonography can give early warning when applied in patients with carotid and lower extremity vascular diseases to delay the incidence of diabetic macroangiopathy and to control the development of cerebral infarction, thus providing an important basis for clinical diagnosis and treatment.


Assuntos
Doenças das Artérias Carótidas/complicações , Doença da Artéria Coronariana/complicações , Diabetes Mellitus Tipo 2/complicações , Doenças Vasculares Periféricas/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Velocidade do Fluxo Sanguíneo , Doenças das Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/fisiopatologia , Estenose das Carótidas/complicações , Estenose das Carótidas/diagnóstico por imagem , Estenose das Carótidas/fisiopatologia , Biologia Computacional , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/fisiopatologia , Diabetes Mellitus Tipo 2/diagnóstico por imagem , Diabetes Mellitus Tipo 2/fisiopatologia , Feminino , Fatores de Risco de Doenças Cardíacas , Hemorreologia , Humanos , Extremidade Inferior/irrigação sanguínea , Extremidade Inferior/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Doenças Vasculares Periféricas/diagnóstico por imagem , Doenças Vasculares Periféricas/fisiopatologia
7.
Sci Rep ; 11(1): 13144, 2021 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-34162963

RESUMO

Tumor progression and metastatic dissemination are driven by cell-intrinsic and biomechanical cues that favor the growth of life-threatening secondary tumors. We recently identified pro-metastatic vascular regions with blood flow profiles that are permissive for the arrest of circulating tumor cells. We have further established that such flow profiles also control endothelial remodeling, which favors extravasation of arrested CTCs. Yet, how shear forces control endothelial remodeling is unknown. In the present work, we aimed at dissecting the cellular and molecular mechanisms driving blood flow-dependent endothelial remodeling. Transcriptomic analysis of endothelial cells revealed that blood flow enhanced VEGFR signaling, among others. Using a combination of in vitro microfluidics and intravital imaging in zebrafish embryos, we now demonstrate that the early flow-driven endothelial response can be prevented upon specific inhibition of VEGFR tyrosine kinase and subsequent signaling. Inhibitory targeting of VEGFRs reduced endothelial remodeling and subsequent metastatic extravasation. These results confirm the importance of VEGFR-dependent endothelial remodeling as a driving force of CTC extravasation and metastatic dissemination. Furthermore, the present work suggests that therapies targeting endothelial remodeling might be a relevant clinical strategy in order to impede metastatic progression.


Assuntos
Endotélio Vascular/fisiologia , Hemorreologia , Migração Transendotelial e Transepitelial , Animais , Animais Geneticamente Modificados , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Embrião não Mamífero/irrigação sanguínea , Embrião não Mamífero/fisiologia , Regulação Neoplásica da Expressão Gênica , Ontologia Genética , Células Endoteliais da Veia Umbilical Humana , Humanos , Técnicas In Vitro , Microscopia Intravital , Microfluídica , Microscopia Confocal , Células Neoplásicas Circulantes , Quinazolinas/farmacologia , Quinazolinas/uso terapêutico , RNA Neoplásico/biossíntese , RNA Neoplásico/genética , Transdução de Sinais/fisiologia , Sunitinibe/farmacologia , Sunitinibe/uso terapêutico , Migração Transendotelial e Transepitelial/efeitos dos fármacos , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/fisiologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/fisiologia , Peixe-Zebra/embriologia
8.
Biomed Mater Eng ; 32(5): 295-308, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33998529

RESUMO

BACKGROUND: Embolization degree acts as an important factor affecting recurrence of aneurysm. OBJECTIVE: To analyze the role of hemodynamics parameters of different degrees of embolization in the occurrence, development and post-treatment of aneurysms, and to determine the specific factors causing the occurrence and recurrence of aneurysms after hemodynamics treatment. Our study provides a theoretical basis for the prevention and treatment of aneurysms. METHODS: Computed tomography angiography data of a patient with cerebral aneurysm was used to model 0%, 24%, 52%, 84% and 100% of endovascular embolization, respectively. The time average wall shear stress, time average wall shear stress, oscillatory shear index, hemodynamics formation index and relative retentive time were used to analyze the changes of hemodynamics indexes in different embolic models. RESULTS: With the increase of embolic rate, the values of time average wall shear stress, time average wall shear stress grade and aneurysm index formation gradually increased, and the values of relative retention time gradually decreased. Oscillatory shear index was higher in patients with incomplete embolization and decreased in patients with complete embolization. CONCLUSIONS: As the degree of embolization increased, the blood flow tended to stabilize, reducing the risk of cerebral aneurysm rupture, and finding that the wall of the vessel junction was susceptible to injury.


Assuntos
Aneurisma Roto , Embolização Terapêutica , Aneurisma Intracraniano , Simulação por Computador , Hemodinâmica , Hemorreologia , Humanos , Hidrodinâmica , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/terapia
9.
Sci Rep ; 11(1): 2800, 2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33531664

RESUMO

Cancer is a leading cause of death and disease worldwide. However, while the survival for patients with primary cancers is improving, the ability to prevent metastatic cancer has not. Once patients develop metastases, their prognosis is dismal. A critical step in metastasis is the transit of cancer cells in the circulatory system. In this hostile microenvironment, variations in pressure and flow can change cellular behavior. However, the effects that circulation has on cancer cells and the metastatic process remain unclear. To further understand this process, we engineered a closed-loop fluidic system to analyze molecular changes induced by variations in flow rate and pressure on primary tumor-derived lung adenocarcinoma cells. We found that cancer cells overexpress epithelial-to-mesenchymal transition markers TWIST1 and SNAI2, as well as stem-like marker CD44 (but not CD133, SOX2 and/or NANOG). Moreover, these cells display a fourfold increased percentage of side population cells and have an increased propensity for migration. In vivo, surviving circulatory cells lead to decreased survival in rodents. These results suggest that cancer cells that express a specific circulatory transition phenotype and are enriched in side population cells are able to survive prolonged circulatory stress and lead to increased metastatic disease and shorter survival.


Assuntos
Adenocarcinoma de Pulmão/secundário , Hemorreologia , Neoplasias Pulmonares/patologia , Células-Tronco Neoplásicas/patologia , Células da Side Population/patologia , Células A549 , Adenocarcinoma de Pulmão/irrigação sanguínea , Animais , Movimento Celular , Sobrevivência Celular , Simulação por Computador , Transição Epitelial-Mesenquimal , Feminino , Humanos , Pulmão/irrigação sanguínea , Pulmão/patologia , Neoplasias Pulmonares/irrigação sanguínea , Técnicas Analíticas Microfluídicas , Ratos , Estresse Mecânico , Microambiente Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Sci Rep ; 11(1): 2642, 2021 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-33514847

RESUMO

Aggregation of human red blood cells (RBC) is central to various pathological conditions from bacterial infections to cancer. When left at low shear conditions or at hemostasis, RBCs form aggregates, which resemble stacks of coins, known as 'rouleaux'. We experimentally examined the interfacial dielectric dispersion of aggregating RBCs. Hetastarch, an RBC aggregation agent, is used to mimic conditions leading to aggregation. Hetastrach concentration is incrementally increased in blood from healthy donors to measure the sensitivity of the technique. Time lapse electrical impedance measurements were conducted as red blood cells form rouleaux and sediment in a PDMS chamber. Theoretical modeling was used for obtaining complex permittivity of an effective single red blood cell aggregate at various concentrations of hetastarch. Time response of red blood cells' impedance was also studied to parametrize the time evolution of impedance data. Single aggregate permittivity at the onset of aggregation, evolution of interfacial dispersion parameters, and sedimentation kinetics allowed us to distinguish differential aggregation in blood.


Assuntos
Sedimentação Sanguínea/efeitos dos fármacos , Agregação Eritrocítica/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Derivados de Hidroxietil Amido/farmacologia , Agregação Eritrocítica/fisiologia , Eritrócitos/fisiologia , Hemorreologia , Hemostasia/efeitos dos fármacos , Humanos , Cinética , Modelos Teóricos , Fenômenos Físicos
11.
Med Sci Sports Exerc ; 53(3): 479-486, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-32925494

RESUMO

PURPOSE: In healthy adults, the impairment of vascular function associated with prolonged sitting can be mitigated with intermittent brief bouts of activity. It is unknown whether these benefits extend to women with polycystic ovary syndrome (PCOS), in whom vascular function is typically impaired and sitting time is high. We examined the acute effect of regularly interrupting sitting time with brief simple resistance activities (SRA) on vascular function in PCOS. METHODS: In a randomized crossover trial, 13 physically inactive women with PCOS (18-45 yr) completed two 3.5-h conditions: 1) uninterrupted sitting (SIT) and 2) sitting interrupted by 3-min bouts of SRA every 30 min. Femoral artery flow-mediated dilation (FMD), resting shear rate, and resting blood flow were measured at 0, 1, and 3.5 h. RESULTS: Mean resting femoral shear rate, averaged across the 3.5 h, significantly increased in the SRA condition relative to the SIT condition (40.1 ± 6.1 vs 62.8 ± 6.1 s-1, P < 0.0001). In addition, mean resting blood flow also significantly increased across the 3.5 h for SRA relative to SIT (45.0 ± 9.8 vs 72.8 ± 9.9 mL·min-1, P < 0.0001). There were no differences between conditions in the temporal change in femoral artery FMD across 3.5 h (Ptime-condition > 0.05 for all). CONCLUSION: Frequently interrupting sitting with SRA acutely increased resting shear rate and blood flow in women with PCOS but did not alter FMD. With sedentary behavior increasing in prevalence, longer-term studies of similar interventions to reduce and break up sitting time are warranted.


Assuntos
Endotélio Vascular/fisiopatologia , Síndrome do Ovário Policístico/fisiopatologia , Treinamento Resistido/métodos , Postura Sentada , Adulto , Estudos Cross-Over , Feminino , Artéria Femoral/fisiologia , Hemorreologia/fisiologia , Humanos , Fluxo Sanguíneo Regional , Comportamento Sedentário , Fatores de Tempo , Vasodilatação/fisiologia
12.
J Vasc Surg Venous Lymphat Disord ; 9(5): 1282-1290, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33338642

RESUMO

OBJECTIVE: The gravitational pressure gradient is considered the driving force of venous reflux. The results from our previous study demonstrated that gravitational force is not a necessary condition for the occurrence of venous reflux. We hypothesized that a force exists in addition to gravity that drives venous reflux. The present study was designed to test this hypothesis by measuring the acceleration of blood flow during venous reflux in a clinical study and by simulating reflux ex vivo in physical models. METHODS: A total of 80 lower extremities of 80 patients with primary incompetence of the great saphenous vein were included in the present study. The cross-sectional area of the great saphenous vein, peak velocity of venous reflux (PV), and time required to achieve the PV (Δt, seconds) were measured on duplex ultrasound scans taken with the patient in the standing rest position. Noncycling operator-dependent distal cuff inflation-deflation was used as the reflux provoking maneuver. The acceleration of venous reflux (areflux) was calculated as areflux = PV/Δt in m/s2. Physical models were used to demonstrate the difference in acceleration between the free-fall stream and the flow forced by suction. RESULTS: The magnitude of areflux was greater than gravity in 24 of 80 extremities (30%), with a range of 9.83 to 24.13 m/s2. The maximum observed value of areflux was approximately 2.5g (24.13 m/s2). The areflux weakly, but statistically significant inversely, correlated with the subject height (r = -0.26; P = .001). The difference in water flow acceleration was 2.5 times between the free-fall model and suction model (9.07 ± 0.2 m/s2 vs 23.32 ± 2.6 m/s2, respectively). CONCLUSIONS: The acceleration of blood flow during reflux exceeded the value of gravitational acceleration, suggesting the action of an additional nongravitational force. The calf muscle pump might create such force by negative pressure during muscle diastole.


Assuntos
Hemorreologia , Músculo Esquelético/fisiologia , Veia Safena/diagnóstico por imagem , Insuficiência Venosa/diagnóstico por imagem , Adulto , Idoso , Velocidade do Fluxo Sanguíneo/fisiologia , Diástole/fisiologia , Feminino , Gravitação , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Estudos Prospectivos , Veia Safena/fisiopatologia , Ultrassonografia Doppler Dupla , Insuficiência Venosa/fisiopatologia , Adulto Jovem
13.
Thromb Haemost ; 120(11): 1548-1556, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32772348

RESUMO

BACKGROUND: For patients treated with dual antiplatelet therapy, standardized drug-specific 3-to-7 day cessation is recommended prior to major surgery to reach sufficient platelet function recovery. Here we investigated the hypothesis that supplemental fibrinogen might mitigate the inhibitory effects of antiplatelet therapy. METHODS AND RESULTS: To this end blood from healthy donors was treated in vitro with platelet inhibitors, and in vitro thrombus formation and platelet activation were assessed. Ticagrelor, acetylsalicylic acid, the combination of both, and tirofiban all markedly attenuated the formation of adherent thrombi, when whole blood was perfused through collagen-coated microchannels at physiological shear rates. Addition of fibrinogen restored in vitro thrombus formation in the presence of antiplatelet drugs and heparin. However, platelet activation, as investigated in assays of P-selectin expression and calcium flux, was not altered by fibrinogen supplementation. Most importantly, fibrinogen was able to restore in vitro thrombogenesis in patients on maintenance dual antiplatelet therapy after percutaneous coronary intervention. CONCLUSION: Thus, our in vitro data support the notion that supplementation of fibrinogen influences the perioperative hemostasis in patients undergoing surgery during antiplatelet therapy by promoting thrombogenesis without significantly interfering with platelet activation.


Assuntos
Fibrinogênio/farmacologia , Ativação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/farmacologia , Trombose/prevenção & controle , Idoso , Aspirina/farmacologia , Sinalização do Cálcio/efeitos dos fármacos , Feminino , Hemorreologia , Heparina/farmacologia , Hirudinas/farmacologia , Humanos , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , Selectina-P/biossíntese , Selectina-P/genética , Ticagrelor/farmacologia , Tirofibana/farmacologia
14.
J Surg Res ; 256: 338-344, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32736062

RESUMO

BACKGROUND: Tube thoracostomy is a commonly performed procedure in trauma patients. The optimal chest tube size is unknown. This study measures chest tube drainage in a controlled laboratory setting and compares measured flowrates to those predicted by the Hagen-Poiseuille equation. MATERIALS AND METHODS: A model of massive hemothorax was created, consisting of a basin containing synthetic blood substitute (aqueous Glycerin and Xanthan gum) and a standard pleur-evac setup at -20 cm H2O suction. Flow measurements were calculated by measuring the time to drain 2L of blood substitute from the basin. Chest tube sizes tested were 20F, 24F, 28F, 32F, and 36F. Thoracostomy opening was modeled using custom built device that represents two ribs, with the distance between varied 2 to 12 mm. Flowrate increases were compared against predicted increases according to the Hagen-Poiseuille equation. Percent of predicted increase was calculated, both incremental increase and using 20F tube benchmark. RESULTS: All tubes were occluded at a 2 mm thoracostomy opening. At 3 mm, 32F and 36F were occluded while smaller tubes were patent. Tubes 28F and larger exhibited high speed and consistent flowrates, even after decreasing thoracostomy opening down to 7 mm, while flowrates rapidly decreased at opening smaller than 7 mm. Smaller 24F and 20F tubes exhibited highly variable flowrates through the system. Maximum flowrates were 21.7, 36.8, 49.6, 55.6, and 61.0 mL/s for 20F-36F tubes, respectively. The incremental increase in flow ratio for increasing chest tube size was 1.69 (20F to 24F), 1.35 (24F to 28F), 1.12 (28F to 32F), and 1.10 (32F to 36F). CONCLUSIONS: The 28F chest tube exhibited high and consistent velocity, while smaller tubes were slower and more variable. Larger tubes offered only slightly higher flowrates. The 28F is a good balance of reasonable size and high flowrate and is likely the optimal size for most clinical applications.


Assuntos
Tubos Torácicos , Drenagem/instrumentação , Hemotórax/cirurgia , Traumatismos Torácicos/cirurgia , Toracostomia/instrumentação , Desenho de Equipamento , Falha de Equipamento , Hemorreologia , Hemotórax/etiologia , Humanos , Escala de Gravidade do Ferimento , Modelos Cardiovasculares , Traumatismos Torácicos/complicações , Fatores de Tempo , Resultado do Tratamento
15.
Biofabrication ; 12(4): 045009, 2020 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-32650321

RESUMO

Blood vessel narrowing and arterial occlusion are pathological hallmarks of atherosclerosis, which involves a complex interplay of perturbed hemodynamics, endothelial dysfunction and inflammatory cascade. Herein, we report a novel circular microfluidic stenosis model that recapitulates atherogenic flow-mediated endothelial dysfunction and blood-endothelial cell (EC) interactions in vitro. 2D and 3D stenosis microchannels with different constriction geometries were fabricated using 3D printing to study flow disturbances under varying severity of occlusion and wall shear stresses (100 to 2000 dynecm-2). Experimental and fluid simulation results confirmed the presence of pathological shear stresses in the stenosis region, and recirculation flow post stenosis. The resultant pathological flow profile induced pro-inflammatory and pro-thrombotic EC state as demonstrated by orthogonal EC alignment, enhanced platelet adhesion at the stenosis, and aberrant leukocyte-EC interactions post stenosis. Clinical utility of the vascular model was further investigated by testing anti-thrombotic and immunomodulatory efficacy of aspirin and metformin, respectively. Overall, the platform enables multi-factorial analysis of critical atherogenic events including endothelial dysfunction, platelets and leukocyte adhesion, and can be further developed into a liquid biopsy tool for cardiovascular risk stratification.


Assuntos
Aterosclerose/patologia , Aterosclerose/fisiopatologia , Vasos Sanguíneos/patologia , Hemorreologia , Imageamento Tridimensional , Inflamação/fisiopatologia , Modelos Cardiovasculares , Perfusão , Vasos Sanguíneos/fisiopatologia , Constrição Patológica , Monitoramento de Medicamentos , Células Endoteliais/patologia , Fatores Imunológicos/farmacologia , Inflamação/patologia , Fenótipo , Trombose/patologia , Engenharia Tecidual
16.
Am J Med Sci ; 360(2): 112-119, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32534720

RESUMO

Diabetic foot ulcer (DFU) is one of the most common and severe complications of diabetes mellitus, which is becoming increasingly prevalent throughout the world, with high mortality and morbidity. Because of the complex pathophysiological processes involved, DFU is difficult to treat effectively with traditional therapies. Ozone therapy, an emerging method, has been reported as potentially beneficial for closure of DFUs and may gradually move to the forefront of clinical practice. Possible mechanisms of action include antioxidant capacity, pathogen inactivation, vascular and endogenous growth factor modulation, and immune system activation. However, some researchers are skeptical about its safety, and clinical trials are lacking. This article reviews the current research and application of ozone therapy for DFUs.


Assuntos
Antibacterianos/uso terapêutico , Pé Diabético/tratamento farmacológico , Fatores Imunológicos/uso terapêutico , Oxidantes Fotoquímicos/uso terapêutico , Ozônio/uso terapêutico , Administração Retal , Administração Tópica , Transfusão de Sangue Autóloga , Pé Diabético/imunologia , Pé Diabético/metabolismo , Hemorreologia , Humanos , Peróxido de Hidrogênio/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Interferons/imunologia , Interleucina-2/imunologia , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Fator de Necrose Tumoral alfa/imunologia
17.
Comput Methods Biomech Biomed Engin ; 23(14): 1060-1070, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32594759

RESUMO

Abdominal aortic aneurysm is a deadly disease that can be treated with different endovascular devices that will distinctly alter the aortic morphology. Computational methods can be used to understand the effect of anatomical changes on aortic hemodynamics. We propose a standardized method to assess morphological and hemodynamic changes of the abdominal aorta through the longitudinal axis of the vessel. Patient-specific CFD simulations were used to quantify these changes for two different endografts before and after surgery. Differences in cross-sectional area, blood pressure, peak blood velocity, wall shear stress, and retrograde blood flow were accurately evidenced with the proposed methodology.


Assuntos
Aneurisma da Aorta Abdominal/fisiopatologia , Aneurisma da Aorta Abdominal/cirurgia , Procedimentos Endovasculares/métodos , Hemodinâmica , Pontos de Referência Anatômicos , Velocidade do Fluxo Sanguíneo , Prótese Vascular , Hemorreologia , Humanos , Modelos Cardiovasculares
18.
J Am Soc Nephrol ; 31(5): 931-945, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32152232

RESUMO

BACKGROUND: Arteriovenous fistulas placed surgically for dialysis vascular access have a high primary failure rate resulting from excessive inward remodeling, medial fibrosis, and thrombosis. No clinically established pharmacologic or perisurgical therapies currently address this unmet need. Statins' induction of multiple anti-inflammatory and antithrombotic effects suggests that these drugs might reduce arteriovenous fistula failure. Yet, the in vivo physiologic and molecular effects of statins on fistula patency and maturation remain poorly understood. METHODS: We randomized 108 C57Bl/6J mice to receive daily atorvastatin 1.14 mg/kg or PBS (control) starting 7 days before end-to-side carotid artery-jugular vein fistula creation and for up to 42 days after fistula creation. We then assessed longitudinally the effects of statin therapy on primary murine fistula patency and maturation. We concomitantly analyzed the in vivo arteriovenous fistula thrombogenic and inflammatory macrophage response to statin therapy, using the fibrin-targeted, near-infrared fluorescence molecular imaging agent FTP11-CyAm7 and dextranated, macrophage-avid nanoparticles CLIO-VT680. RESULTS: In vivo molecular-structural imaging demonstrated that atorvastatin significantly reduced fibrin deposition at day 7 and macrophage accumulation at days 7 and 14, findings supported by histopathologic and gene-expression analyses. Structurally, atorvastatin promoted favorable venous limb outward remodeling, preserved arteriovenous fistula blood flow, and prolonged primary arteriovenous fistula patency through day 42 (P<0.05 versus control for all measures). CONCLUSIONS: These findings provide new in vivo evidence that statins improve experimental arteriovenous fistula patency and maturation, indicating that additional clinical evaluation of statin therapy in patients on dialysis undergoing arteriovenous fistula placement is warranted.


Assuntos
Derivação Arteriovenosa Cirúrgica , Atorvastatina/uso terapêutico , Fibrina/metabolismo , Macrófagos/efeitos dos fármacos , Grau de Desobstrução Vascular/efeitos dos fármacos , Animais , Atorvastatina/farmacologia , Artéria Carótida Interna , Colágeno/metabolismo , Feminino , Fibrose/prevenção & controle , Hemorreologia , Inflamação/prevenção & controle , Veias Jugulares/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Imagem Molecular , Nanopartículas , RNA Mensageiro/biossíntese , Distribuição Aleatória , Trombose/prevenção & controle , Transcrição Gênica , Dispositivos de Acesso Vascular
19.
Phytother Res ; 34(7): 1704-1720, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32185841

RESUMO

Microcirculation, which connects macrocirculation and cells between arterioles and venules, plays a major role in the early onset of a variety of diseases. In this article, a dextran-induced microcirculation dysfunction (MCDF) model rats were adopted to evaluate the effects and mechanism of Salvia miltiorrhiza stem-leaf extracts based on plasma and urine metabonomics. The results showed the effective components of S. miltiorrhiza stem-leaf could significantly improve the hemorheology and coagulation index of MCDF rats and callback the expression of endothelin-1 (ET-1), induciblenitric oxide synthase (iNOS), vascularendothelial growth factor (VEGF), P-Selectin, thromboxane A2, 6-keto-PGF1α , TNF-α, and interleukin-1ß to control group in MCDF rats. The decrease of microvessel density (MVD) in lung and thymus caused by MCDF was upgraded by Salvia miltiorrhiza stem-leaf. Based on the plasma and urine metabolic data, 20 potential biomarkers were identified. These biomarkers are mainly related to linoleic acid metabolism, glutathione metabolism, pantothenate and coenzyme A biosynthesis, pentose and glucuronate interconversions, pyruvate metabolism, glyoxylate and dicarboxylate metabolism, beta-alanine metabolism, and citrate cycle. The results indicated that the effective components of S. miltiorrhiza stem-leaf can improve the hemorheological disorder and vascular endothelial function. Meanwhile, the effective components can regulate potential biomarkers and correlated metabolic pathway, which can provide guidance for the research and development of new drugs for MCDF.


Assuntos
Alcenos/química , Células Endoteliais/efeitos dos fármacos , Flavonoides/química , Hemorreologia/efeitos dos fármacos , Microcirculação/efeitos dos fármacos , Folhas de Planta/química , Caules de Planta/química , Polifenóis/química , Salvia miltiorrhiza/química , Animais , Masculino , Ratos , Ratos Wistar
20.
Crit Care Clin ; 36(2): 267-292, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32172813

RESUMO

Oxygen (O2) delivery, which is fundamental to supporting patients with critical illness, is a function of blood O2 content and flow. This article reviews red blood cell (RBC) physiology and dysfunction relevant to disordered O2 delivery in the critically ill. Flow is the focus of O2 delivery regulation: O2 content is relatively fixed, whereas flow fluctuates greatly. Thus, blood flow volume and distribution vary to maintain coupling between O2 delivery and demand. This article reviews conventional RBC physiology influencing O2 delivery and introduces a paradigm for O2 delivery homeostasis based on coordinated gas transport and vascular signaling by RBCs.


Assuntos
Estado Terminal , Eritrócitos/patologia , Eritrócitos/fisiologia , Trifosfato de Adenosina/sangue , Deformação Eritrocítica , Hemorreologia , Homeostase/fisiologia , Humanos , Microcirculação/fisiologia , Óxido Nítrico/sangue
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