977 resultados para vascular cells


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OBJECTIVE: To evaluate the influence of lactic acid on immune mediator release from vaginal epithelial cells. METHODS: The human vaginal epithelial cell line, VK2/E6E7, was cultured in the presence or absence of physiological concentrations of lactic acid, and in the presence or absence of the viral Toll-like receptor 3 agonist, poly (inosinic acid: cytidylic acid). Supernatants were assayed by enzyme-linked immunosorbent assay (ELISA) for interleukin (IL)-1 beta, IL-6, IL-8, IL-23, transforming growth factor (TGF)-beta and secretory leukocyte protease inhibitor. RESULTS: Vaginal epithelial cells spontaneously released IL-1 beta (25.9 pg/mL), IL-8 (1.0 ng/mL), TGF-beta (175 pg/mL), and secretory leukocyte protease inhibitor (33.8 ng/mL). Only TGF-beta production was marginally enhanced (49%) by addition of lactic acid alone. Poly (inosinic acid: cytidylic acid) by itself stimulated the release of IL-6 (305 pg/mL) and enhanced IL-8 production (2.8 ng/mL). The combination of poly (inosinic acid: cytidylic acid) and lactic acid markedly increased IL-8 production (5.0 ng/mL) and induced the release of IL-1 beta (96.2 pg/mL). The poly (inosinic acid: cytidylic acid)-mediated lactic acid effect on IL-1 beta and IL-8 release was abrogated when the lactic acid was neutralized or if acetic acid was substituted for lactic acid. CONCLUSION: Lactic acid enhances the release of selective mediators from vaginal epithelial cells and stimulates antiviral immune responses. (Obstet Gynecol 2011;118:840-6) DOI: 10.1097/AOG.0b013e31822da9e9

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Lactic acid is the predominant acid present in the vagina. We evaluated the consequences of lactic acid, at physiological levels present in the vagina, on cytokine responses of peripheral blood mononuclear cells (PBMCs) obtained from 10 individuals in the presence or absence of bacterial lipopolysaccharide. Preincubation of PBMCs in 15 mM lactic acid before the addition of lipopolysaccharide resulted in a 246% mean increase in interleukin-23 (IL-23) secretion over that released in the presence of lipopolysaccharide alone (P=0.0068). The lipopolysaccharide-induced production of tumor necrosis factor-alpha, IL-6, IL-10 and IL-12 was unaffected by lactic acid. IL-23 stimulation was not observed if the lactic acid was neutralized before its addition to the culture medium or if hydrochloric acid was substituted for lactic acid. In the absence of lipopolysaccharide, lactic acid did not stimulate the production of IL-23 or any of the other cytokines. The increase in IL-23 production was proportional to the lactic acid concentration over a 15-60 mM range. We conclude that at body sites characterized by lactic acid accumulation, such as in the human vagina, exposure to gram-negative bacteria results in selective IL-23 production, leading to a subsequent preferential stimulation of the Th17 T lymphocyte pathway.

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The effect of intra-bone injection of differentiated rat bone marrow mesenchymal stem cells (BMMSCs) into the femur of osteoporotic female rats was studied. Osteoporosis was induced in Wistar female rats by bilateral ovariectomy. Then, 0.75 million BMMSCs isolated from healthy rats were injected into the femurs of osteoporotic rats. Histomorphometric analysis and histology clearly revealed improvements in the treated group as compared to untreated group. In 2 months, the femurs of treated rats, unlike untreated rats, showed trabecular bone percentage almost similar to the femurs from control healthy rats. To confirm the origin of newly formed bone, the experiment was repeated with BMMSCs isolated from green fluorescent protein transgenic rats. Confocal microscopy demonstrated green fluorescent protein-positive cells at the surface of trabecular bone of the treated rats. We investigated in vitro osteogenic differentiation of BMMSCs isolated from osteoporotic rats by studying alkaline phosphatase activity, collagen synthesis, and the ability to form mineralized nodules. Osteoporotic BMMSCs showed less differentiation capabilities as compared to those isolated from healthy rats. The results clearly demonstrated the importance of BMMSCs in osteoporosis and that the disease can be treated by injection of BMMSCs.

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In animal models, interstitial angiotensin II (ang II) and AT1 receptor (AT1R) are key mediators of renal inflammation and fibrosis in progressive chronic nephropathies. We hypothesized that these molecules were overexpressed in patients with progressive glomerulopathies. In this observational retrospective study, we described the expression of ang II and AT1R by immunohistochemistry in kidney biopsies of 7 patients with minimal change disease (MCD) and in 25 patients with progressive glomerulopathies (PGPs). Proteinuria, serum albumin, and serum creatinine were not statistically different between MCD and PGP patients. Total expression of ang II and AT1R was not statistically different between MCD (108.7 +/- 11.5 and 73.2 +/- 13.6 cells/mm(2), respectively) and PGN patients (100.7 +/- 9.0 and 157.7 +/- 13.8 cells/mm(2), respectively; p>0.05). Yet, interstitial expression of ang II and AT1R (91.6 +/- 16.0 and 45.6 +/- 5.4 cells/mm(2), respectively) was higher in patients with PGN than in those with MCD (22.0 +/- 4.1 and 17.9 +/- 2.9 cells/mm(2), respectively, p<0.05), as was the proportion of interstitial fibrosis (11.0 +/- 0.7% versus 6.1 +/- 1.2%, p<005). In patients with MCD, ang II and AT1R expressions predominate in the tubular compartment (52% and 36% of the positive cells, respectively). In those with PGP, the interstitial expression of ang II and AT1R predominates (58% and 45%, respectively). In conclusion, interstitial expression of ang II and AT1R is increased in patients with progressive glomerulopathies. The relationship of these results and interstitial fibrosis and disease progression in humans warrants further investigations.

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The influence of various culture parameters on the attachment of a recombinant baculovirus to suspended insect cells was examined under normal culture conditions. These parameters included cell density, multiplicity of infection, and composition of the cell growth medium. It was found that the fractional rate of virus attachment was independent of the multiplicity of infection but dependent on the cell density. A first order mathematical model was used to simulate the adsorption kinetics and predict the efficiency of virus attachment under the various culture conditions. This calculated efficiency of virus attachment was observed to decrease at high cell densities, which was attributed to cell clumping. It was also observed that virus attachment was more efficient in Sf900II serum free medium than it was in IPL-41 serum-supplemented medium. This effect was attributed to the protein in serum which may coat the cells and so inhibit adsorption. A general discussion relating the observations made in-these experiments to the kinetics of recombinant baculovirus adsorption to suspended insect cells is presented.

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Human follicle stimulating hormone is a pituitary glycoprotein that is essential for the maintenance of ovarian follicle development and testicular spermatogenesis. Like other members of the glycoprotein hormone family, it contains a common a subunit and a hormone specific beta subunit. Each subunit contains two glycosylation sites. The specific structures of the oligosaccharides of human follicle stimulating hormone have been shown to influence both the in vitro and in vivo bioactivity. Since the carbohydrate structure of a protein reflects the glycosylation apparatus of the host cells in which the protein is expressed, we examined the isoform profiles, in vitro bioactivity and metabolic clearance of a preparation of purified recombinant human follicle stimulating hormone derived from a stable, transfected Sp2/0 myeloma cell line, and pituitary human follicle stimulating hormone. Isoelectric focussing and chromatofocussing studies of human follicle stimulating hormone preparations both showed a more basic isoform profile for the recombinant human follicle stimulating hormone compared to that of pituitary human follicle stimulating hormone. The recombinant human follicle stimulating hormone had a significantly higher radioreceptor activity compared to that of pituitary human follicle stimulating hormone, consistent with a greater in vitro potency. Pharmacokinetic studies in rats indicated a similar terminal half life (124 min) to that of the pituitary human follicle stimulating hormone (119 min). Preliminary carbohydrate analysis showed recombinant human follicle stimulating hormone to contain high mannose and/or hybrid type, in addition to complex type carbohydrate chains, terminating with both alpha 2,3 and alpha 2,6 linked sialic acids. These results demonstrate that recombinant human follicle stimulating hormone made in the Sp2/0 myeloma cells is sialylated, has a more basic isoform profile, and has a greater in vitro biological potency compared to those of the pituitary human follicle stimulating hormone.

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The current study aims to ascertain the fate of the melanocyte stimulating hormone (MSH) receptor and its ligand [Nle(4), D-Phe(7)]alpha-MsH (NDP-MSH) following binding to murine B16 melanoma cells. Cells were incubated with [I-125]-NDP-MSH for up to 180 min and binding, internalization and degradation determined. Intracellular trafficking of the radiolabel was assessed !using Percoll density gradient centrifugation of homogenized cells. Receptor down-regulation and receptor mRNA levels were also measured over 96 hr after exposure to 1 mu M ligand. NDP-MSH accumulation increased with time in a temperature-dependent manner and was inhibited by excess peptide. The ligand was rapidly internalized and translocated to the lysosomal compartment where it was degraded. Internalization was accompanied by a loss or down-regulation of cell surface receptors, suggesting internalization of the NDP-MSH-receptor complex. No recycling of the receptors between the plasma membrane and intracellular compartments could be detected in this cell-hue. Approximately 15% of the surface receptors were resistant to down-regulation, possibly indicating receptor heterogeneity. Down-regulation persisted ibr up to 96 hr and was accompanied by a decrease in MSH receptor mRNA levels 48 hr after treatment. However, before this time, transcript levels were the same in treated and control cells. In contrast to what was seen with NDP-MSH, cell surface receptors removed with trypsin wc:re rapidly replaced. These results show that NDP-MSH not only induced MSH receptor :internalization but also inhibited receptor turnover, resulting in a prolonged down-regulation. It is concluded that, in B16 cells, the MSH receptor undergoes ligand-dependent internalization, resulting in a prolonged down-regulation. Copyright (C) 1996 Elsevier Science Ltd

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The intercalated discs of working myocardium and Purkinje fibers of the monkey heart were examined by scanning and transmission electron microscopy. The NaOH/ultrasonication technique resulted in the digestion of connective tissue and a separation of the intercellular junctions of intercalated discs, such that these could be visualized three-dimensionally. The intercalated discs of ventricular myocytes, atrial myocytes and Purkinje fibers vary considerably in number and configuration, as do the intercalated discs of the three different layers of the ventricular myocardium. Myocytes in the subepicardial, middle and subendocardial layers of the ventricle have 1-3, 4-5 and 5-6 intercalated discs at the end of these cells, respectively, Those in the endocardial layer are characterized by the presence of small laterally-placed intercalated discs. Atrial myocytes and Purkinje fibers usually only have 1-2 intercalated discs, Individual intercalated discs in ventricular myocytes have complicated stairs with 10-30 steps and corresponding risers, while those of atrial myocytes and Purkinje fibers have simple stairs with 1-3 steps and risers, Steps equivalent to the plicate segments are characterized by densely-packed microplicae and finger-like microprojections which greatly increase surface area in vertricular myocytes, Microprojections in atrial myocytes and Purkinje fibers are sparse by comparison, Risers equivalent to the interplicate segments containing large gap junctional areas are most numerous in left ventricular myocytes, followed by right ventricular myocytes, Purkinje fibers and atrial myocytes in decreasing order. The geometric arrangement of the various types of myocytes may be related with impulse propagation. Large intercalated discs of cell trunks and series branches may participate in longitudinal propagation, while small laterally-placed ones may be the site of transverse propagation.

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The main aim of this study is to evaluate the capacity of human dental pulp stem cells (hDPSC), isolated from deciduous teeth, to reconstruct large-sized cranial bone defects in nonimmunosuppressed (NIS) rats. To our knowledge, these cells were not used before in similar experiments. We performed two symmetric full-thickness cranial defects (5 x 8 mm) on each parietal region of eight NIS rats. In six of them, the left side was supplied with collagen membrane only and the right side (RS) with collagen membrane and hDPSC. In two rats, the RS had collagen membrane only and nothing was added at the left side (controls). Cells were used after in vitro characterization as mesenchymal cells. Animals were euthanized at 7, 20, 30, 60, and 120 days postoperatively and cranial tissue samples were taken from the defects for histologic analysis. Analysis of the presence of human cells in the new bone was confirmed by molecular analysis. The hDPSC lineage was positive for the four mesenchymal cell markers tested and showed osteogenic, adipogenic, and myogenic in vitro differentiation. We observed bone formation 1 month after surgery in both sides, but a more mature bone was present in the RS. Human DNA was polymerase chain reaction-amplified only at the RS, indicating that this new bone had human cells. The us e of hDPSC in NIS rats did not cause any graft. rejection. Our findings suggest that hDPSC is an additional cell resource for correcting large cranial defects in rats and constitutes a promising model for reconstruction of human large cranial defects in craniofacial surgery.

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OBJECTIVES: The aim of this study was to determine the impact of endovascular surgery versus open vascular technique training in a Brazilian teaching service. DESIGN: Cross-sectional study. SETTING: Hospital das Clinicas-Faculty of Medicine University of Sao Paulo, a tertiary institutional hospital Brazil. PARTICIPANTS: We reviewed 1,040 arterial operations performed during 2 distinct time periods: January 1995 to December 1996, and January 2006 to December 2007. Based on the disease treated, the procedures were classified into the following 5 groups: abdominal aortic aneurysms (AAA), aorto-iliac obstructive disease (Al), obstructive disease of the femoropoplitealtibial segment (FP), carotid disease (C), and others (0). The operations were also divided into an endovascular surgery (ES) group and an open surgery (OS) group. We compared the number of open and endovascular procedures for each arterial disease group during both periods. RESULTS: During the 2006-2007 period, 654 patients were treated surgically, whereas over the 1995-1996 period, 386 arterial operations were performed. A. significant increase in endovascular procedures (p < 0.001) was found from the 1995-1996 period to the 2006-201)7 period (35 vs 351, respectively) in all groups, whereas open surgery showed a slight increase in the number of procedures in the AAA and 0 groups only. In the 1995-1996 period, OS was the primary surgical method for all groups, but in the 2006-2007 time frame, OS was performed more frequently than ES only in the AAA and 0 groups. Considering all vascular disease groups, OS was the technique used in 90.9% (351 of 386) of the operations during 1995-1996, whereas in 2006-2007, OS was performed in only 46.3% (303 of 654) of the procedures. CONCLUSIONS: The increase in the number of ES observed over the past decade has had little impact on OS procedures performed at our medical center, not bringing harm to open surgical training. (J Surg 68:19-23. (C) 2011 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.)

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We have observed previously that Ca2+ pump-mediated Ca2+ efflux is elevated in cultured aortic smooth muscle cells from spontaneously hypertensive rats compared to those from Wistar-Kyoto rat controls. The objective of this work was to determine if these strains differ in mRNA levels for the PMCA1 isoform of the plasma membrane Ca2+-ATPase and the SERCA2 isoform of the sarcoplasmic reticulum Ca2+-ATPase. mRNA levels were compared in cultured aortic smooth muscle cells from 10-week-old male rats. PMCA1 and SERCA2 mRNA levels were elevated in SHR compared to WKY. Angiotensin II increased the level of PMCA1 and SERCA2 mRNA in both strains. These studies provide further evidence for alterered Ca2+ homeostasis in hypertension at the level of Ca2+ transporting ATPases in the spontaneously hypertensive rat model. These data are also consistent with the hypothesis that the expression of these two Ca2+ pumps may be linked. (C) 1997 Academic Press

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CD40-1igand (CD40-L), a member of the tumour necrosis family of transmembrane glycoproteins, is rapidly and transiently expressed on the surface of recently activated CD4+ T cells. CD40 is expressed by B cells, monocytes and dendritic cells. Interactions between CD40-L and CD40 induce B cell proliferation, differentiation, immunoglobulin production and isotype switching as well as monocyte activation and dendritic cell differentiation. Since the rheumatoid synovium is characterized by T cell activation, B cell immunoglobulin production, monocyte cytokine production and dendritic cell differentiation, the expression and function of CD40-L in RA was examined. RA synovial fluid (SF) T ceils expressed CD40-L mRNA, as well as low level cell surface CD40-L. A subset of CD4+ RA synovial fluid T cells could express cell surface CD40-L within 15 rain of in vitro activation even in the presence of cycloheximide. CD40-L expressed by RA SF T cells was functional, since RA SF T cells, but not normal PB T cells, stimulated CD40-L dependent B cell immunoglobulin production in the absence of in vitro T cell activation. These data indicate that SF T cells express functionally significant levels of surface CD40-L, and have the potential for rapid upregulation of surface expression from preformed CD40-L stores. Thus, CD40-L is likely to play a central role in the perpetuation of RA by induction of Ig synthesis, cytokine production and dendritic cell differentiation. Moreover, the data provide important evidence of recent activation of RA synovial T cells. Of importance, blockade of CD40-L may prove highly effective as a disease modifying therapy for RA.

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Arteriovenous fistula involving renal artery and inferior vena cava are rare. We report the case of a 47-year-old woman with a chronic arteriovenous fistula between right renal artery and inferior vena cava due to a penetrating trauma. Another finding was a vena cava aneurysm caused by the fistula. The patient was successfully treated with a covered stent in the renal artery. Diagnosis and postoperative control have been documented with CT scan. Endovascular techniques may be effective and minimally invasive option for treatment and renal preservation in renal-cava arteriovenous fistulae.

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Purpose: The bladder is normally impermeable to possible hostile environmental factors and toxic urinary wastes. Any disruption of the permeability barrier would permit the leakage of urine constituents into the underlying cells layers and subsequent inflammation. Protamine sulfate, which increases urothelial permeability, is used in experimental models of cystitis. We examined whether protamine sulfate alone could cause bladder inflammation or if the association of protamine sulfate and urine is needed for this condition. Materials and Methods: Female Wistar rats (Center for the Development of Experimental Models for Medicine and Biology, Federal University of Sao Paulo, Sao Paulo, Brazil) had the bladder catheterized and instilled with protamine sulfate (10 mg) or sterile saline for 30 minutes. To exclude urine other groups of rats underwent bilateral nephrectomy and the same procedure was used. One day after instillation the bladders were removed for histopathology. Edema and vascular congestion were graded from 0-none to 3-severe. Polymorphonuclear and mast cells were counted. The Kruskal-Wallis test was performed for statistical analysis. Results: Intravesical instillation of protamine sulfate in nonnephrectomized rats led to inflammation, in contrast to findings in rats instilled with saline. On the other hand, nephrectomized rats showed no inflammatory changes following the instillation of protamine sulfate or saline. The mast cell count was similar in all groups. Conclusions: Bladder inflammation in this experimental model of urothelial injury was not due to protamine sulfate alone. The association of protamine sulfate and urine was necessary to trigger the inflammatory cascade. Thus, urine indeed has an important role in the development of bladder inflammation in an environment of higher urothelial permeability.

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Mechanisms of leukocyte NADPH oxidase regulation remain actively investigated. We showed previously that vascular and macrophage oxidase complexes are regulated by the associated redox chaperone PDI. Here, we investigated the occurrence and possible underlying mechanisms of PDI-mediated regulation of neutrophil NADPH oxidase. In a semirecombinant cell-free system, PDI inhibitors scrRNase (100 mu g/mL) or bacitracin (1 mM) near totally suppressed superoxide generation. Exogenously incubated, oxidized PDI increased (by similar to 40%), whereas PDIred diminished (by similar to 60%) superoxide generation. No change occurred after incubation with PDI serine-mutated in all four redox cysteines. Moreover, a mimetic CxxC PDI inhibited superoxide production by similar to 70%. Thus, oxidized PDI supports, whereas reduced PDI down-regulates, intrinsic membrane NADPH oxidase complex activity. In whole neutrophils, immunoprecipitation and colocalization experiments demonstrated PDI association with membrane complex subunits and prominent thiol-mediated interaction with p47(phox) in the cytosol fraction. Upon PMA stimulation, PDI was mobilized from azurophilic granules to cytosol but did not further accumulate in membranes, contrarily to p47(phox). PDI-p47(phox) association in cytosol increased concomitantly to opposite redox switches of both proteins; there was marked reductive shift of cytosol PDI and maintainance of predominantly oxidized PDI in the membrane. Pulldown assays further indicated predominant association between PDIred and p47(phox) in cytosol. Incubation of purified PDI (> 80% reduced) and p47(phox) in vitro promoted their arachidonate-dependent association. Such PDI behavior is consistent with a novel cytosolic regulatory loop for oxidase complex (re) cycling. Altogether, PDI seems to exhibit a supportive effect on NADPH oxidase activity by acting as a redox-dependent enzyme complex organizer. J. Leukoc. Biol. 90: 799-810; 2011.