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1.
Liu Q  Guan L  Huang B  Li W  Su Q  Yu M  Xu X  Luo T  Lin S  Sun X  Chen M  Chen X 《Cell biology international》2011,35(6):631-638
Adult peripheral blood-derived cells are able to differentiate into a variety of cell types, including nerve cells, liver-like cells and epithelial cells. However, their differentiation into retina-like cells is controversial. In the present study, transdifferentiation potential of human adult peripheral blood mononuclear cells into retina-like cells and integration into the retina of mice were investigated. Freshly isolated adult peripheral blood mononuclear cells were divided into two groups: cells in group I were cultured in neural stem cell medium, and cells in group II were exposed to conditioned medium from rat retinal tissue culture. After 5 days, several distinct cell morphologies were observed, including standard mononuclear, neurons with one or two axons and elongated glial-like cells. Immunohistochemical analysis of neural stem cell, neuron and retina cell markers demonstrated that cells in both groups were nestin-, MAP2 (microtubule-associated protein)- and GFAP (glial fibrillary acidic protein)-positive. Flow cytometry results suggested a significant increase in nestin-, MAP2- and CD16-positive cells in group I and nestin-, GFAP-, MAP2-, vimentin- and rhodopsin-positive cells in group II. To determine survival, migration and integration in vivo, cell suspensions (containing group I or group II cells) were injected into the vitreous or the peritoneum. Tissue specimens were obtained and immunostained 4 weeks after transplantation. We found that cells delivered by intravitreal injection integrated into the retina. Labelled cells were not detected in the retina of mice receiving differentiated cells by intraperitoneal injection, but cells (groups I and II) were detected in the liver and spleen. Our findings revealed that human adult peripheral blood mononuclear cells could be induced to transdifferentiate into neural precursor cells and retinal progenitor cells in vitro, and the differentiated peripheral blood mononuclear cells can migrate and integrate into the retina in vivo.  相似文献   

2.
We have determined the effect of pulsatile flow on segmental vascular resistance in lungs from 29 adult rabbits. In group I (n = 4), II (n = 8), and III (n = 8) lungs were isolated. In group IV (n = 9) rabbits were anesthetized, their chests were opened, and lungs were studied in vivo. Group I and II lungs had steady-flow perfusion: group I with intact vasotonus and group II with papaverine treatment. Group III lungs (papaverine treated) were perfused for two consecutive 45-min periods with steady and pulsatile flow. In all isolated lungs and in lungs of five anesthetized rabbits, we measured pressures in subpleural 20- to 50-microns-diam arterioles and venules by use of the micropipette servo-nulling method. Measurement of distribution of blood flow in lungs of four anesthetized rabbits by use of radiolabeled microspheres revealed no abnormality of blood flow to the micropunctured lobe. We found that total and segmental vascular resistances were similar in group I and II lungs, with microvessels representing 55% of total resistance. In group III lungs, total resistance was 30% lower during pulsatile flow than during steady flow because of a lower microvascular resistance. Lungs in vivo (group IV) had a significantly lower total vascular resistance than isolated lungs and had a low fractional resistance in microvessels (approximately 28%). We conclude that, in isolated perfused adult rabbit lungs, vascular resistance is very high, particularly in the microvascular segment, and that pulsatile flow decreases microvascular resistance.  相似文献   

3.
To study the mechanical effects of lung edema on the pulmonary circulation, we determined the longitudinal distribution of vascular resistance in the arteries, veins, and microvessels, and the distribution of blood flow in isolated blood-perfused rabbit lungs with varying degrees of edema. Active vasomotor changes were eliminated by adding papaverine to the perfusate. In three groups of lungs with either minimal [group I, mean wet-to-dry weight ratio (W/D) = 5.3 +/- 0.6 (SD), n = 7], moderate (group II, W/D = 8.5 +/- 1.2, n = 10), or severe (group III, W/D = 9.9 +/- 1.6, n = 5) edema, we measured by direct micropuncture the pressure in subpleural arterioles and venules (20-60 micron diam) and in the interstitium surrounding these vessels. We also measured pulmonary arterial and left atrial pressures and lung blood flow, and in four additional experiments we used radio-labeled microspheres to determine the distribution of blood flow during mild and severe pulmonary edema. In lungs with little or no edema (group I) we found that 33% of total vascular pressure drop was in arteries, 60% was in microvessels, and 7% was in veins. Moderate edema (group II) had no effect on total vascular resistance or on the vascular pressure profile, but severe edema (group III) did increase vascular resistance without changing the longitudinal distribution of vascular resistance in the subpleural microcirculation. Perivascular interstitial pressure relative to pleural pressure increased from 1 cmH2O in group I to 2 in group II to 4 in group III lungs.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

4.
Ferritin levels in blood serum and mononuclear cells of the peripheral blood were determined in 60 patients with chronic lymphatic leukemia (group I), and 31 patients with other lymphomas of the low and medium degree of malignancy (group II). Significantly higher blood serum and mononuclear cells ferritin was found in the examined patients than in 54 healthy individuals. Particularly high ferritin levels were seen in blood serum of patients of group II in whom clinical stage of the disease was high. Moreover, moderate correlation of ferritin content in mononuclear cells and absolute leucocytosis was found in group I. This parameter correlated well with the percentage of poorly differentiated cells (group II).  相似文献   

5.
Blood viscosity and cardiac output in acute experimental anemia.   总被引:3,自引:0,他引:3  
The significance of blood viscosity alterations during anemia was evaluated in dogs under morphine-chloralose anesthesia. In group I, anemia (mean hematocrit 18.1 +/- 1.3 vol %) was produced by exchange transfusion with clinical dextran (avg mol wt 70,000). In group II, anemia was produced (mean hematocrit 19.9 +/- 0.88 vol %) with 500,000 molecular weight dextran, thus preventing the decrease in blood viscosity in group I. The cardiac output increase in group I (93.4%) with low-viscosity anemia was significantly greater than in group II (43.3%) with unchanged blood viscosity. Group III animals were transfused with a clinical dextran-red cell mixture, and group IV animals received a 500,000 mol wt dextran-red cell mixture. In group III, blood viscosity and cardiac output did not change. In group IV, blood viscosity rose and cardiac output fell significantly. The results suggest that a change in blood viscosity exerts a significant effect upon cardiac output, especially during acute dextran-exchange anemia.  相似文献   

6.
7.
The present study was designed to evaluate, in Wistar rats, the effect of high- or low-salt diet on the hemodynamic parameters and on the renal and lumbar sympathetic nerve activity. The renal gene expression of the renin angiotensin system components was also evaluated, aiming to find some correlation between salt intake, sodium homeostasis and blood pressure increase. Male Wistar rats received low (0.06% Na, TD 92141-Harlan Teklad), a normal (0.5% Na, TD 92140), or a high-salt diet (3.12% Na, TD 92142) from weaning to adulthood. Hemodynamic parameters such as cardiac output and total peripheral resistance, and the renal and lumbar sympathetic nerve activity were determined (n=45). Plasma renin activity, plasma and renal content of angiotensin (ANG) I and II, and the renal mRNA expression of angiotensinogen, renin, AT1 and AT2 receptors were also measured (n=24). Compared to normal- and low-salt diet-, high-salt-treated rats were hypertensive and developed an increase (P<0.05) in total peripheral resistance and lumbar sympathetic nerve activity. A decrease in renal renin and angiotensinogen-mRNAs and in plasma ANG II and plasma renin activity was also found in salt overloaded animals. The renal sympathetic nerve activity was higher (P<0.05) in low- compared to high-salt-treated rats, and was associated with an increase (P<0.05) in renal ANG I and II and with a decrease (P<0.05) in AT2 renal mRNA. Plasma ANG I and II and plasma renin activity were higher in low- than in normal-salt rats. Our results show that increased blood pressure is associated with increases in lumbar sympathetic nerve activity and total peripheral resistance in high-salt-treated rats. However, in low-salt-treated rats an increase in the renal sympathetic nerve was correlated with an increase in the renal content of ANG I and II and with a decrease in AT2 renal mRNA. These changes are probably in favor of the antinatriuretic response and the sodium homeostasis in the low-salt group.  相似文献   

8.
摘要 目的:研究苓桂术甘汤对老年脾胃气虚型功能型消化不良患者的临床治疗效果,并探讨治疗对患者胃蛋白酶原、胃泌素和血液流变学的影响。方法:选取2020年1月到2021年10月在我院接受治疗的老年脾胃气虚型功能型消化不良患者120例,按治疗方式分为对照组以及研究组,对照组患者给予常规药物治疗,研究组患者在对照组基础上加用苓桂术甘汤进行治疗,比较两组患者临床治疗疗效和治疗前后生活质量评分、中医症候积分、血清胃蛋白酶I和II、血清胃泌素-17、血液流变学。结果:(1)研究组患者临床治疗总有效率显著高于对照组(93.33 % vs 75.00 %,P<0.05);(2)治疗后,两组患者的生活质量评分升高,而中医症候积分降低,且研究组优于对照组(P<0.05);(3)两组患者治疗后血胃蛋白酶I和II、血清胃泌素-17均显著降低,并且治疗后研究组低于对照组(P<0.05);(4)两组患者治疗后血液流变学指标(高切全血黏度、低切全血黏度和血浆黏度)均显著降低,并且研究组降低程度显著高于对照组(P<0.05)。结论:加用苓桂术甘汤治疗老年脾胃气虚型功能型消化不良可显著提高临床治疗疗效,改善患者生活质量,降低患者血清胃蛋白酶原、胃泌素以及血流变学指标表达。  相似文献   

9.
目的:探讨树脂灌血液灌流对血液透析顽固性高血压患者血压及肾素-血管紧张素.醛固酮系统的影响。方法:选择我院82例,均分为I组和II组各41例,I组患者采用金宝8LR聚酰胺膜透析器进行常规透析,II组患者在常规透析的基础上串联树脂血液灌流,检测两组患者治疗前和治疗后3个月血清肌酐、尿素氮变化情况,和患者体内肾素活性、血管紧张素II和醛固酮变化情况,并对血压变化值进行比较。结果:两组患者治疗后3个月血肌酐、血尿素氮均明显较治疗前降低,I组患者治疗后3个月收缩压和舒张压较治疗前均无明显变化,II组治疗后3个月收缩压和舒张压均较治疗前明显降低,I组治疗后3个月肾素、血管紧张素II和醛固酮较治疗前无明显差异,II组治疗后3个月肾素、血管紧张素II和醛固酮较治疗前均明显降低。结论:血液透析联合树脂吸附灌在保证有效清除患者体内代谢物质的同时角色较好的控制患者血压。  相似文献   

10.
The prototype member of the complementation group II temperature-sensitive (ts) mutants of vesicular stomatitis virus, ts II 052, has been investigated. In ts II 052-infected HeLa cells at the restrictive temperature (39.5 degrees C), reduced viral RNA synthesis was observed by comparison with infections conducted at the permissive temperature (30 degrees C). It was found that for an infection conducted at 39.5 degrees C, no 38S RNA or intracytoplasmic nucleocapsids were present. For nucleocapsids isolated from ts II 052 purified virions or from ts II 052-infected cells at 30 degrees C, the RNA was sensitive to pancreatic RNase after an exposure at 39.5 degrees C in contrast to the resistance observed for wild-type virus. The nucleocapsid stability of wild-type virus when heated to 63 degrees C or submitted to varying pH was not found in nucleocapsids extracted from ts II 052 purified virions. The data suggest that for ts II 052 there is an altered relationship between the viral 38S RNA and the nucleocapsid protein(s) by comparison with wild-type virus. Such results argue for the complementation group II gene product being N protein, so that the ts defect in ts II 052 represents an altered N protein.  相似文献   

11.
Surgical correction of synostotic frontal plagiocephaly (unilateral coronal synostosis) focuses on the asymmetry of the forehead and orbits. However, there is controversy regarding whether nasal angulation should be addressed during primary fronto-orbital advancement in infancy. This prospective study was undertaken to answer that question. Preoperative and postoperative anthropometric measurements were obtained for 19 infants with nonsyndromic synostotic frontal plagiocephaly. The measurements included nasal angulation, nasion-to-endocanthion distance, nasion-to-exocanthion distance, and exocanthion-to-tragion distance. All patients underwent bilateral parallelogrammatic fronto-orbital correction. Closing wedge nasal ostectomy was performed for group I (n = 14) and was not performed for group II (n = 5). The average age at the time of follow-up assessments was 3 years 8 months (range, 1 to 14 years) in group I and 5 years 5 months (range, 2 to 15 years) in group II. A statistically significant change was observed for patients who underwent primary correction of nasal angulation; the change correlated with improved naso-orbital symmetry, as judged with nasion-to-endocanthion and nasion-to-exocanthion measurements (p < 0.01 and p < 0.05, respectively). Group I patients exhibited an average preoperative nasal angulation of 9.15 +/- 0.8 degrees that decreased to 3.1 +/- 0.6 degrees postoperatively (p < 0.01). Group II patients exhibited an average preoperative nasal angulation of 6.4 +/- 0.7 degrees that was unchanged postoperatively at 7.2 +/- 1 degrees. The improvement in nasal angulation in group I was particularly striking because the patients in group II exhibited, on average, a lesser degree of preoperative nasal deviation (p < 0.01). This prospective comparison of fronto-orbital correction of synostotic frontal plagiocephaly with and without nasal correction confirmed an earlier study and demonstrated that angulation of the nasal pyramid does not self-correct within 5 years after traditional bilateral fronto-orbital repair. Closing wedge nasal ostectomy results in improved nasal angulation and naso-orbital symmetry, without evidence of distortion or inhibition of nasal growth.  相似文献   

12.
Although the effects of red blood cell (RBC) aggregation on low-shear rate blood viscosity are well known, the effects on in vivo flow resistance are still not fully resolved. The present study was designed to explore the in vivo effects of RBC aggregation on flow resistance using a novel technique to enhance aggregation: cells are covalently coated with a block copolymer (Pluronic F-98) and then suspended in unaltered plasma. RBC aggregation was increased in graded steps by varying the Pluronic concentration during cell coating and was verified by microscopy and erythrocyte sedimentation rate (ESR), which increased by 200% at the highest Pluronic level. RBC suspensions were perfused through an isolated in situ guinea pig hindlimb preparation while the arterial perfusion pressure was held constant at 100 mmHg via a pressure servo-controlled pump. No significant effects of enhanced RBC aggregation were observed when studies were conducted in preparations with intact vascular control mechanisms. However, after inhibition of smooth muscle tone (using 10(-4) M papaverin), a significant change in flow resistance was observed in a RBC suspension with a 97% increase of ESR. Additional enhancements of RBC aggregation (i.e., 136 and 162% increases of ESR) decreased flow resistance almost to control values. This was followed by another significant increase in flow resistance during perfusion with RBC suspensions with a 200% increase of ESR. This triphasic effect of graded increases of RBC aggregation is most likely explained by an interplay of several hemodynamic mechanisms that are triggered by enhanced RBC aggregation.  相似文献   

13.
The effects of a vasopressin (AVP) pressor antagonist, d(CH2)5Tyr(Me)AVP, on mean arterial pressure (MAP), total peripheral resistance (TPR), cardiac output (CO), and the distribution of CO were investigated by the microsphere technique in three groups of pentobarbital anesthetized rats: intact (I), saralasin pretreated (II), and phentolamine pretreated (III). Saralasin and phentolamine were infused intravenously to inactivate the renin-angiotensin and alpha-adrenergic systems, respectively. The AVP antagonist decreased MAP and TPR in all groups and it caused a greater depressor effect in groups II and III than in group I. In group I, AVP antagonist increased blood flow (BF) to the stomach and skin. In group II, AVP antagonist increased BF to the muscle and skin. In group III, AVP antagonist markedly increased BF to the muscle. Therefore, the degree of vasoconstrictor influence exerted by AVP in different vascular beds varies depending on endogenous vasomotor tone from the renin-angiotensin and (or) sympathetic nervous systems.  相似文献   

14.
To evaluate the effect of blood storage on the yield of micronuclei (MN) in both irradiated (in vivo and ex vivo) and unirradiated peripheral blood lymphocytes (PBL), we applied the MN assay in cytokinesis-blocked (CB) PBL obtained from healthy subjects (n=11), and from cancer patients (n=10) who were undergoing fractionated partial-body radiotherapy (xRT). The heparinized blood samples were exposed to 137Cs-irradiation (0 Gy or 2 Gy) immediately after blood collection and were stored upright in test tubes either at room temperature (22 degrees C) or in the refrigerator (5 degrees C). Duplicate whole blood cultures from each sample were set up at 0 h, 96 h, and 120 h after ex vivo irradiation. Giemsa (10%) stained slides were prepared from each culture. MN yield was determined per 1000 binucleated cells. As compared to that obtained from the corresponding fresh blood samples, we found that (1) the 22 degrees C blood storage temperature did not affect MN yields in PBL of either healthy subjects or cancer patients up to 96 h, either with or without ex vivo irradiation; and (2) while blood samples were stored at 5 degrees C, the MN yield increased significantly in PBL of healthy subjects (with or without ex vivo irradiation) at 120 h, and in cancer patients (with ex vivo irradiation) at 96 h and 120 h. Since handling of the blood sample is important for CBMN assay during shipment or in the laboratory, our findings showed that blood storage at 22 degrees C or at 5 degrees C up to 96 h appeared to provide insignificant variations of the MN results as compared to fresh blood samples. However, the 96 h of blood storage at 5 degrees C elevated the MN frequency in ex vivo irradiated PBL of cancer patients who were undergoing xRT.  相似文献   

15.
It has been postulated that a proportion of recurrent miscarriage (RM) might be due to immune causes. The objective was to determine whether cytokine expression in peripheral blood mononuclear cell is altered in patients with a history of RM. We compared the levels of IL-2, IL-4, IL-10, IL-13, TGFbeta1 and IFNgamma in the supernatant of Phytohemagglutinin stimulated mononuclear cells in 21 women with RM at the time of 3rd or higher abortion (group I), 32 women who were at least 3 months past their 3rd or higher abortion (group II) and 32 pregnant women with no history of abortion (group III). Gestational age was matched between groups I and III. Group I had higher level of IL-2 than group III (P=0.001). Group II showed higher level of IL-2 (P=0.001) and IFNgamma (P=0.015) than group III. The production of IL-10 by mononuclear cells of group III was higher than both group I (P=0.002) and group II (P=0.001). There was no difference in the levels of IL-2, IL-10 and IFNgamma between groups I and II. Also, the levels of IL-4, IL-13, and TGFbeta1 were similar among the groups. The data indicate an elevation of Th1 cytokines in women with RM as compared to normal pregnant women, and IL-10 is an important cytokine in the maintenance of pregnancy.  相似文献   

16.
The apparent viscosity of blood in glass tubes declines with decreasing diameter (F?hraeus-Lindqvist effect) and exhibits a distinctive minimum at 6-7 microm. However, flow resistance in vivo in small vessels is substantially higher than predicted by in vitro viscosity data. The presence of a thick endothelial surface layer (ESL) has been proposed as the primary cause for this discrepancy. Here, a physical model is proposed for microvascular flow resistance as a function of vessel diameter and hematocrit in vivo; it combines in vitro blood viscosity with effects of a diameter-dependent ESL. The model was developed on the basis of flow distributions observed in three microvascular networks in the rat mesentery with 392, 546, and 383 vessel segments, for which vessel diameters, network architecture, flow velocity, and hematocrit were determined by intravital microscopy. A previously described hemodynamic simulation was used to predict the distributions of flow and hematocrit from the assumed model for effective blood viscosity. The dependence of ESL thickness on vessel diameter was estimated by minimizing deviations of predicted values for velocities, flow directions, and hematocrits from measured data. Optimal results were obtained with a layer thickness of approximately 0.8-1 microm for 10- to 40-microm-diameter vessels and declined strongly for smaller diameters, with an additional hematocrit-dependent impact on flow resistance exhibiting a maximum for approximately 10-microm-diameter vessels. These results show that flow resistance in vivo can be explained by in vitro blood viscosity and the presence of an ESL and indicate the rheologically effective thickness of the ESL in microvessels.  相似文献   

17.
The adhesion of highly activated neutrophils to cerebral microvascular endothelial cells (MVECs) may contribute to disruption and hyperpermeability of the blood-brain barrier (BBB) after cardiac surgery with prolonged cardiopulmonary bypass (CPB). A correlation between CPB duration and neutrophil-mediated BBB damage has not been investigated on the cellular level yet. Therefore, we studied the effects of neutrophils from cardiac surgery patients with CPB time <80 min (group I; n=8) and >80 min (group II; n=8) on the integrity of cultured porcine MVEC. Ex vivo, neutrophils of group II but not of group I significantly degraded the zonula adherens molecule beta-catenin whereas VE-cadherin and occludin were not modified. The transendothelial electric resistance as a measure for the integrity of the endothelial monolayers was reduced over time in both groups. In conclusion, prolonged CPB time entails neutrophil-mediated decrease in MVEC beta-catenin expression, and thus may be an important trigger for BBB disruption.  相似文献   

18.
Prior work demonstrated dependence of the change in blood pressure during the Valsalva maneuver (VM) on the extent of thoracic hypovolemia and splanchnic hypervolemia. Thoracic hypovolemia and splanchnic hypervolemia characterize certain patients with postural tachycardia syndrome (POTS) during orthostatic stress. These patients also experience abnormal phase II hypotension and phase IV hypertension during VM. We hypothesize that reduced splanchnic arterial resistance explains aberrant VM results in these patients. We studied 17 POTS patients aged 15-23 yr with normal resting peripheral blood flow by strain gauge plethysmography and 10 comparably aged healthy volunteers. All had normal blood volumes by dye dilution. We assessed changes in estimated thoracic, splanchnic, pelvic-thigh, and lower leg blood volume and blood flow by impedance plethysmography throughout VM performed in the supine position. Baseline splanchnic blood flow was increased and calculated arterial resistance was decreased in POTS compared with control subjects. Splanchnic resistance decreased and flow increased in POTS subjects, whereas splanchnic resistance increased and flow decreased in control subjects during stage II of VM. This was associated with increased splanchnic blood volume, decreased thoracic blood volume, increased heart rate, and decreased blood pressure in POTS. Pelvic and leg resistances were increased above control and remained so during stage IV of VM, accounting for the increased blood pressure overshoot in POTS. Thus splanchnic hyperemia and hypervolemia are related to excessive phase II blood pressure reduction in POTS despite intense peripheral vasoconstriction. Factors other than autonomic dysfunction may play a role in POTS.  相似文献   

19.
Male Wistar rats were hypophysectomized 7 days (group 1) and 4-7 weeks (group II) before exposure to hypothermia (4 degrees C for 1 1/2 h). The hypophysectomized rats from group I were devoid of both the posterior lobe and the adenohypophysis, while the rats from group II had the posterior hypophysis but not the adenohypophysis regenerated. A decreased arginine-vasopressin (AVP) blood level in group I (32%) and a very high level of AVP in group II (311%, P less than 0.05) was determined by RIA. The exposure to hypothermia did not influence the AVP plasma level. The thyroid hypofunction was revealed morphometrically in both hypophysectomized groups. Nevertheless, cooling stimulated the thyroid glands in rats of both experimental groups, like it was in the control. Thus, there is no evidence that thyroid gland reaction to hypothermia is affected by AVP. Cooling caused an increase of corticosteroid blood and adrenal cortex content in nonoperated control rats as well as in group II, but not in group I of experimental animals. Hence, it may be assumed that when the adenohypophysis is ablated, a high AVP blood level is necessary to realize the adrenal cortex response to hypothermia.  相似文献   

20.
By means of biomicroscopy, electrophysiological and hemorheological techniques effect of plasmapheresis with use of various plasma -substituting solutions and their combination on microcirculation, hemodynamics and rheology of blood at peritonitis has been studied in the experiment on 329 white non-inbred rats and on 50 mature dogs. Three periods of disturbances in hemomicrocirculation of the small intestine mesentery at peritonitis have been revealed: I (3-6h)--a relative well-being and compensatory reactions in the system of hemomicrocirculation; II (9-15h)--development of disturbances in the aggregate state of blood; III (18-24h)--pronounced disturbances in hemomicrocirculation. Plasmapheresis at peritonitis facilitates: to better functioning of the microcirculatory system, namely, a sharp increasing of the blood flow rate, joining into the blood flow of capillaries that did not function previously and increasing functional capacity of the capillary bed; decreasing blood viscosity and aggregation of erythrocytes. Plasmapheresis applied at peritonitis produces a favourable effect to hemodynamics, evident as an increasing minute and stroke volume of the blood flow, cardiac index, the left ventricle activity and decrease in peripheral vascular resistance.  相似文献   

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