Arteriovenous fistula for chronic hemodialysis in pediatric candidates for renal transplantation: Technical details and refinements

AVFs may be considered the best type of venous access for chronic hemodialysis in pediatric patients with more than 20 kg who are not likely to receive a kidney transplant or be transitioned to peritoneal dialysis within one yr. The aim of the study was to report the experience in the creation of AVFs in pediatric candidates for renal transplantation using microsurgical vascular techniques, with emphasis on the details of the surgical technique. Forty children underwent 50 fistula creations - 31 radial-cephalic, 11 brachial-cephalic, five brachial-basilic and three saphenous-femoral. The vein was anastomosed to the artery in an end-to-lateral fashion by using two separate 8/0 prolene running sutures. The overall patency rate was 76.0%:22 (70.9%) of the radial-cephalic fistulas, nine (81.8%) of the brachial-cephalic, five (100.0%) of the brachial-basilic and two (66.6%) of the saphenous-femoral. There was no significant difference in patency rates between the brachial-cephalic, brachial-basilic and radial-cephalic fistulas. The incidences of fistula patency were not different for patients weighing < 20 kg compared with patients weighing > 20 kg. AVF remains as a satisfactory method for providing hemodialysis in children. The utilization of microsurgical techniques with some technical refinements described herein permits the achievement of high fistula patency rates.

Aerobic Exercise Improves Reverse Cholesterol Transport in Cholesteryl Ester Transfer Protein Transgenic Mice

We analyzed the effect of a 6-week aerobic exercise training program on the in vivo macrophage reverse cholesterol transport (RCT) in human cholesteryl ester transfer protein (CETP) transgenic (CETP-tg) mice. Male CETP-tg mice were randomly assigned to a sedentary group or a carefully supervised exercise training group (treadmill 15 m/min, 30 min sessions, five sessions per week). The levels of plasma lipids were determined by enzymatic methods, and the lipoprotein profile was determined by fast protein liquid chromatography (FPLC). CETP activity was determined by measuring the transfer rate of (14)C-cholesterol from HDL to apo-B containing lipoproteins, using plasma from CETP-tg mice as a source of CETP. The reverse cholesterol transport was determined in vivo by measuring the [(3)H]-cholesterol recovery in plasma and feces (24 and 48 h) and in the liver (48 h) following a peritoneal injection of [(3)H]-cholesterol labeled J774-macrophages into both sedentary and exercise trained mice. The protein levels of liver receptors were determined by immunoblot, and the mRNA levels for liver enzymes were measured using RT-PCR. Exercise training did not significantly affect the levels of plasma lipids or CETP activity. The HDL fraction assessed by FPLC was higher in exercise-trained compared to sedentary mice. In comparison to the sedentary group, a greater recovery of [(3)H]-cholesterol from the injected macrophages was found in the plasma, liver and feces of exercise-trained animals. The latter occurred even with a reduction in the liver CYP7A1 mRNA level in exercised trained animals. Exercise training increased the liver LDL receptor and ABCA-1 protein levels, although the SR-BI protein content was unchanged. The RCT benefit in CETP-tg mice elicited by exercise training helps to elucidate the role of exercise in the prevention of atherosclerosis in humans.

B-1 cells temper endotoxemic inflammatory responses

Sepsis syndrome is caused by inappropriate immune activation due to bacteria and bacterial components released during infection. This syndrome is the leading cause of death in intensive care units. Specialized B-lymphocytes located in the peritoneal and pleural cavities are known as B-1 cells. These cells produce IgM and IL-10, both of which are potent regulators of cell-mediated immunity. It has been suggested that B-1 cells modulate the systemic inflammatory response in sepsis. In this study, we conducted in vitro and in vivo experiments in order to investigate a putative role of B-1 cells in a murine model of LPS-induced sepsis. Macrophages and B-1 cells were studied in monocultures and in co-cultures. The B-1 cells produced the anti-inflammatory cytokine IL-10 in response to LPS. In the B-1 cell-macrophage co-cultures, production of proinflammatory mediators (TNF-alpha, IL-6 and nitrite) was lower than in the macrophage monocultures, whereas that of IL-10 was higher in the co-cultures. Co-culture of B-1 IL-10(-/-) cells and macrophages did not reduce the production of the proinflammatory mediators (TNF-alpha, IL-6 and nitrite). After LPS injection, the mortality rate was higher among Balb/Xid mice, which are B-1 cell deficient, than among wild-type mice (65.0% vs. 0.0%). The Balb/Xid mice also presented a proinflammatory profile of TNF-alpha, IL-6 and nitrite, as well as lower levels of IL-10. In the early phase of LPS stimulation, B-1 cells modulate the macrophage inflammatory response, and the main molecular pathway of that modulation is based on IL-10-mediated intracellular signaling. (C) 2010 Elsevier GmbH. All rights reserved.

LOSS OF CD40 ENDOGENOUS S-NITROSYLATION DURING INFLAMMATORY RESPONSE IN ENDOTOXEMIC MICE AND PATIENTS WITH SEPSIS

Signal transduction through the surface molecule CD40 is critical for cellular activation in immunoinflammatory states such as sepsis. The mechanisms regulating this pathway are not completely understood. Because CD40 displays potentially regulatory cysteine residues and CD40 is probably exposed to NO in the inflammatory milieu, we hypothesized that S-nitrosylation, the interaction of NO with cysteines residues, acts as a post-translational modification on CD40, coregulating the signaling activity and, therefore, the level of cellular activation. As assessed by the biotin switch and the reduction/chemiluminescence S-nitrosylation detection techniques, CD40 was found to be S-nitrosylated endogenously and upon exposure to NO donors in both human and murine macrophages. S-nitrosylation of CD40 was associated with milder activation by its ligand (CD40L), leading to reduced in vitro cytokine (IL-1 beta, IL-12, and TNF-alpha) production, which was reversed in the presence of inhibitors of NO synthesis. S-nitrosylated CD40 was found in resting RAW 246.7 macrophages and BALB/c mice peritoneal macrophages, turning into the denitrosylated state upon in vitro or systemic exposure, respectively, to LPS. Moreover, monocytes from patients with sepsis displayed denitrosylated CD40 in contrast to the CD40 S-nitrosylation measured in healthy individuals. Finally, in an attempt to explain how S-nitrosylation regulates CD40 activation, we demonstrate that NO affects the redistribution of CD40 on the cell surface, which is a requirement for optimal signal transduction. Our results support a novel post-translational regulatory mechanism in which the CD40 signal may be, at least in part, dependent on cellular activation-induced receptor denitrosylation.

Tubal sterilisation, hysterectomy and decreased risk of ovarian cancer

We have examined the effect of tubal sterilisation and hysterectomy on risk of ovarian cancer in a large case-control study in eastern Australia involving 824 women aged 18-79 years, diagnosed with epithelial ovarian cancer between 1990 and 1993, and 855 controls randomly selected from the electoral roll. Relative risks for ovarian cancer were estimated using multiple categorical regression to adjust for age, parity, oral contraceptive use and other risk factors. Tubal sterilisation was associated with a 39% reduction in risk of ovarian cancer (RR 0.61, 95% Cl 0.46-0.85) and hysterectomy with a 36% reduction (RR 0.64, 95% Cl 0.48-0.85). Risk remained low 25 years after surgery and was reduced irrespective of sterilisation technique, and estimates were similar among various types of epithelial ovarian cancer. The greatest reduction (74%) was observed among women with primary peritoneal tumours. Pelvic infection and use of vaginal sprays or contraceptive foams were not related to ovarian cancer, while use of talc in the perineal region slightly but significantly increased risk among women with patent fallopian tubes. Reportedly heavy or painful menses, perhaps associated with retrograde flow, were associated with ovarian cancer, and reduction in risk of disease after hysterectomy was greatest among women who had heavy periods. Our findings support the theory that contaminants from the vagina, such as talc, and from the uterus, such as endometrium, gain access to the peritoneal cavity through patent fallopian tubes and may enhance the malignant transformation of ovarian surface epithelium. Surgical tubal occlusion may reduce the risk of ovarian cancer by preventing the access of such agents. (C) 1997 Wiley-Liss, Inc.

Galectin-3 plays a modulatory role in the life span and activation of murine neutrophils during early Toxoplasma gondii infection

Galectins are beta-galactoside-binding lectins involved in several biological processes and galectin-3 (Gal-3) is related to modulation of immune and inflammatory responses. This study aimed to evaluate the role of Gal-3 in the life span and biological functions of murine neutrophils during in vitro infection by virulent Toxoplasma gondii RH strain. Inflammatory peritoneal neutrophils (N phi) from C57BL/6 wildtype (WT) and Gal-3 knockout (KO) mice were cultured in the presence or absence of parasites and analyzed for phosphatidylserine (PS) exposure and cell death using Annexin-V and propidium iodide staining, and cell viability by MU assay. Cell toxicities determined by lactate dehydrogenase (LDH), degranulation by lysozyme release, and cytokine production were measured in NO culture supernatants. Phorbol myristate acetate (PMA)- or zymosan-dependent reactive oxygen species (ROS) were measured in N phi cultures. Our results demonstrated that Gal-3 is involved in the increase of the viable Not. number and the decrease of PS exposure and cell death following T. gondii infection. We also observed that Gal-3 downmodulates gondii-induced N phi toxicity as well as N phi degranulation regardless of infection. Furthermore, Gal-3 expression by N phi was associated with increased levels of IL-10 in the beginning and decreased levels of TNF-alpha later on, regardless of parasite infection, as well as with decreased levels of IL-6 and increased IL-12 levels, following early parasite infection. Our results also showed that Gal-3 suppresses PMA- but not zymosan-induced ROS generation in N phi following T. gondii infection. In conclusion, Gal-3 plays an important modulatory role by interfering in N phi life span and activation during early T gondii infection. (C) 2009 Elsevier GmbH. All rights reserved.

Human leukemia inhibitory factor upregulates LDL receptors on liver cells and decreases serum cholesterol in the cholesterol-fed rabbit

In a previous study, we found that the cytokine (human) leukemia inhibitory factor (hLIF) significantly reduced plasma cholesterol levels and the accumulation of lipid in aortic tissues of cholesterol-fed rabbits after 4 weeks of treatment. The mechanisms by which this occurs were investigated in the present study. This involved examining the effect of hLIF on (1) the level of plasma cholesterol at different times throughout the 4-week treatment and diet period; (2) smooth muscle cell (SMC) and macrophage-derived foam cell formation in vitro; and (3) LDL receptor expression and uptake in the human hepatoma cell line HepG2. At time zero, an osmotic minipump (2-mL capacity; infusion rate, 2.5 mu L/h; 28 days) containing either hLIF (30 mu g.kg(-1).d(-1)) or saline was inserted into the peritoneal cavity of New Zealand White rabbits (N=24). Rabbits were divided into four groups of six animals each. Group 1 received a normal diet/saline; group 2, a normal diet/hLIF; group 3, a 1% cholesterol diet/saline; and group 4, a 1% cholesterol diet/hLIF. hLIF had no effect on the plasma lipids or artery wall of group 2 rabbits (normal diet). However, in group 4 rabbits, plasma cholesterol levels and the percent surface area of thoracic aorta covered by fatty streaks was decreased by approximate to 30% and 80%, respectively, throughout all stages of the 4-week treatment period. In vitro, hLIF failed to prevent lipoprotein uptake by either SMCs or macrophages (foam cell formation) when the cells were exposed to P-VLDL for 24 hours. In contrast, hLIF (100 ng/mL) added to cultured human hepatoma HepG2 cells induced a twofold or threefold increase in intracellular lipid accumulation in the medium containing 10% lipoprotein-deficient serum or 10% fetal calf serum, respectively. This was accompanied by a significant non-dose-dependent increase in LDL receptor expression in hLIF-treated HepG2 cells incubated with LDL (20 mu g/mL) when compared with controls (P

Effect of fish oil containing parenteral lipid emulsions on neutrophil chemotaxis and resident-macrophages` phagocytosis in rats

Background & aims: There is scarce information about immune function and parenteral. fish oil (FO). The influence of a new parenteral. lipid emulsion (LE) containing fish oil (SMOF) was experimentally evaluated on neutrophils` chemotaxis and macrophages` phagocytosis. Methods: Adult mate Lewis rats (n = 40) were randomized into five groups; one non-surgical. control and four to receive parenteral LE or saline infusion through jugular vein catheterization: SMOF (mixture of 30% medium-chain triglycerides, 30% soybean, 25% olive and 15% fish oils); MCT/LCT (physical mixture of 50% medium-chain triglycerides and 50% soybean oil); MCT/LCT/FO (80% MCT/LCT supplemented with 20% FO) and SS (saline). In the 5th experimental day and after intravenous colloidal carbon injection, blood and tissue (liver, lung and spleen) samples were collected and immunological analyses were performed. Results: LE didn`t influence neutrophil chemotaxis. SMOF didn`t influence phagocytosis (p > 0.05) while MCT/LCT and MCT/LCT/FO LE increased the number of liver and lung resident macrophages that had engaged in phagocytosis compared with CO-NS and SS (p < 0.05). Only MCT/LCT/FO increased the number of spleen resident macrophages that had engaged in phagocytosis (p < 0.05). Conclusions: LE, independently of composition, had no influence on neutrophils` chemotaxis, but showed different effect on phagocytosis by macrophages. SMOF LE had neutral effect while fish oil LE enriched with MCT/LCT LE increased resident-macrophages` phagocytosis. (c) 2007 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

Stem cells in endometrium and their role in the pathogenesis of endometriosis

The human endometrium is a dynamic tissue that undergoes cycles of growth and regression with each menstrual cycle. Adult progenitor stem cells are likely responsible for this remarkable regenerative capacity; these same progenitor stem cells may also have an enhanced capacity to generate endometriosis if shed in a retrograde fashion. The progenitor stem cells reside in the uterus; however, less-committed mesenchymal stem cells may also travel from other tissues such as bone marrow to repopulate the progenitor population. Mesenchymal stem cells are also involved in the pathogenesis of endometriosis and may be the principle source of endometriosis outside of the peritoneal cavity when they differentiate into endometriosis in ectopic locations. Finally, besides progenitor stem cells, recent publications have identified multipotent stem cells in the endometrium. These multipotent stem cells are a readily available source of cells that are useful in tissue engineering and regenerative medicine. Endometrial stem cells have been used to generate chondrocytes, myocytes, neurons, and adiposites in vitro as well as to replace dopaminergic neurons in a murine model of Parkinson`s disease.

A selective cyclooxygenase-2 inhibitor suppresses the growth of endometriosis with an antiangiogenic effect in a rat model

Objective: To analyze the antiangiogenic effects of the selective cyclooxygenase-2 (COX-2) inhibitor parecoxib on the growth of endometrial implants in a rat model of peritoneal endometriosis. Design: Pharmacologic interventions in an experimental model of peritoneal endometriosis. Setting: Research laboratory in the Federal University of Rio de Janeiro. Animal(s): Twenty female Sprague-Dawley rats with experimentally induced endometriosis. Intervention(s): After implantation and establishment of autologous endometrium onto the peritoneum abdominal wall, rats were randomized into groups and treated with parecoxib or the vehicle by IM injection for 30 days. Main Outcome Measure(s): Vascular density, the expression of vascular endothelial growth factor (VEGF) and its receptor Flk-1, the distribution of activated macrophages, the expression of COX-2, and the prostaglandin concentration in the endometriotic lesions treated with parecoxib were analyzed. Result(s): The treatment significantly decreased the implant size, and histologic examination indicated mostly atrophy and regression. A reduction in microvessel density and in the number of macrophages, associated with decreased expression of VEGF and Flk-1, also were observed. The treatment group showed a low concentration of prostaglandin E(2). Conclusion(s): These results suggest that the use of COX-2 selective inhibitors could be effective to suppress the establishment and growth of endometriosis, partially through their antiangiogenic activity. (Fertil Steril (R) 2010; 93: 2674-9. (C) 2010 by American Society for Reproductive Medicine.)

High serum follistatin levels in women with ovarian endometriosis

Follistatin is an activin-binding protein produced by several tissues, including endometrium and endometriotic implants. We aimed to quantify follistatin in patients with ovarian endometriosis and investigate its value as a diagnostic marker. Women undergoing laparoscopic excision of ovarian endometrioma (n = 52) or other benign ovarian cysts (n = 52) were studied, plus women with non-ovarian endometriosis (n = 11) and healthy controls (n = 27). Serum was collected from all subjects, and peritoneal and cystic fluid from a subset with endometrioma. Follistatin was measured by enzyme-linked immunosorbent assay. The diagnostic accuracy of follistatin to detect endometrioma was evaluated by receiver operating characteristic (ROC) curve and compared with cancer antigen (CA)-125. Serum follistatin was increased in women with ovarian endometrioma (2080 +/- 94 pg/ml) compared with controls (545 +/- 49 pg/ml, P < 0.001), other benign ovarian cysts (795 +/- 60 pg/ml, P < 0.001) or non-ovarian endometriosis (1271 +/- 115 pg/ml, P < 0.001). Cystic fluid showed a higher concentration of follistatin (9850 +/- 4461 pg/ml) than peritoneal fluid (1885 +/- 261 pg/ml, P < 0.001) and serum (P < 0.001). Follistatin levels detected 48/52 cases of endometrioma (92% sensitivity) at 1433 pg/ml cut-off, corresponding to 92% specificity. CA-125 detected only 44% of endometriomas with 90% specificity. ROC curve comparison showed follistatin was more accurate than CA-125 to discriminate women with endometrioma either from controls or women with other benign ovarian cysts (P < 0.0001). Serum follistatin is increased in women with endometriosis and allows clear distinction between endometrioma and other benign ovarian cysts. Follistatin has the sensitivity and specificity to become a useful clinical marker of ovarian endometrioma.

Interleukin-12 but not interieukin-18 is associated with severe endometriosis

Objective: To evaluate interleukin (IL)-12 and IL-18 levels in the serum and peritoneal fluid of women with and without endometriosis. Design: Cross-sectional survey. Setting: University hospital. Patients: Interleukin-12 and IL-18 levels were compared in 105 patients submitted to laparoscopy because of symptoms suggestive of endometriosis (pain and/or infertility). The disease was confirmed in 72 patients (study group), while in 33 patients findings were not compatible with endometriosis (control group). Intevention(s): Blood sample and peritoneal fluid were obtained from patients during videolaparoscopy. Main Outcome Measure(s): The levels of IL-12 and IL-18 in peripheral blood and peritoneal fluid were determined and compared with the stage and site of the disease and histologic classification. Result(s): IL-12 levels measured in peritoneal fluid were higher inpatients with endometriosis compared with the control group. A significant increase in IL-12 levels was found when the more advanced stages of the disease were compared with the initial stages. No statistically significant differences were found in IL-18 levels, either in serum or in peritoneal fluid samples. Conclusion(s): Patients with severe endometriosis have higher IL-12 levels irrespective of IL-18 levels, suggesting that in this disease an alternative pathway is involved in induction of the Th1 immune response. (Fertil Steril (R) 2009;91:320-4. (C)2009 by American Society for Reproductive Medicine.)

Vascular density and distribution of vascular endothelial growth factor (VEGF) and its receptor VEGFR-2 (Flk-1) are significantly higher in patients with deeply infiltrating endometriosis affecting the rectum

Objective: To analyze vascular density and immunolocalization of angiogenic vascular endothelial growth factor (VEGF) and its receptor Flk-1 in the proliferative and secretory eutopic human endometrium. and in three different sites of endometriosis: the ovary, bladder, and rectum. Design: Prospective study. Setting: University hospital. Patient(s): Thirty women with endometriosis (10 ovarian, 1.0 bladder, 10 rectal) and 32 control women (10 proliferative endometrium, 10 secretory endometrium, 4 normal ovary, 4 normal bladder, 4 normal rectum). Intervention(s): Normal endometrial samples were obtained from women during laparoscopic ablation of subserous myoma, and biopsy specimens of endometriosis were obtained from patients undergoing surgery for the diagnosis and treatment of endometriosis. Normal tissues of ovary, bladder, and rectum were obtained from these organs beside the lesions of endometriosis. Main Outcome Measure(S): Blood vessels were quantified according to the number of von Willebrand factor-positive endothelial cells. The VEGF and Flk-1 distribution were evaluated semiquantitatively by immunohistochemical staining. Result(s): More blood vessels were found in cases of endometriosis, particularly rectal endometriosis, compared with the respective control samples and with the eutopic endometrium, and they were localized in endometrial stroma around the glands. The VEGF and Flk-1 expression levels were also higher in cases of endometriosis, especially rectal endometriosis. Conclusion(s): Vascularization and VEGF and Flk-1 expression are significantly higher in deeply infiltrating endometriosis affecting the rectum, reinforcing the hypothesis that antiangiogenesis therapy may constitute a new modality of treatment, especially in cases of deep endometriosis involving the rectum.

Intravenous glutamine decreases lung and distal organ injury in an experimental model of abdominal sepsis

Introduction The protective effect of glutamine, as a pharmacological agent against lung injury, has been reported in experimental sepsis; however, its efficacy at improving oxygenation and lung mechanics, attenuating diaphragm and distal organ injury has to be better elucidated. In the present study, we tested the hypothesis that a single early intravenous dose of glutamine was associated not only with the improvement of lung morpho-function, but also the reduction of the inflammatory process and epithelial cell apoptosis in kidney, liver, and intestine villi. Methods Seventy-two Wistar rats were randomly assigned into four groups. Sepsis was induced by cecal ligation and puncture surgery (CLP), while a sham operated group was used as control (C). One hour after surgery, C and CLP groups were further randomized into subgroups receiving intravenous saline (1 ml, SAL) or glutamine (0.75 g/kg, Gln). At 48 hours, animals were anesthetized, and the following parameters were measured: arterial oxygenation, pulmonary mechanics, and diaphragm, lung, kidney, liver, and small intestine villi histology. At 18 and 48 hours, Cytokine-Induced Neutrophil Chemoattractant (CINC)-1, interleukin (IL)-6 and 10 were quantified in bronchoalveolar and peritoneal lavage fluids (BALF and PLF, respectively). Results CLP induced: a) deterioration of lung mechanics and gas exchange; b) ultrastructural changes of lung parenchyma and diaphragm; and c) lung and distal organ epithelial cell apoptosis. Glutamine improved survival rate, oxygenation and lung mechanics, minimized pulmonary and diaphragmatic changes, attenuating lung and distal organ epithelial cell apoptosis. Glutamine increased IL-10 in peritoneal lavage fluid at 18 hours and bronchoalveolar lavage fluid at 48 hours, but decreased CINC-1 and IL-6 in BALF and PLF only at 18 hours. Conclusions In an experimental model of abdominal sepsis, a single intravenous dose of glutamine administered after sepsis induction may modulate the inflammatory process reducing not only the risk of lung injury, but also distal organ impairment. These results suggest that intravenous glutamine may be a potentially beneficial therapy for abdominal sepsis.

In vitro infectivity of species of Leishmania (Viannia) responsible for American cutaneous leishmaniasis

There is little available information regarding the infectivity of New World Leishmania species, particularly those from the Amazonian Brazil, where there are six species of the subgenus Viannia causing American cutaneous leishmaniasis (ACL). The aim of this study was to compare, in vitro, the potential infectivity of the following Leishmania (Viannia) spp.: L. (V.) braziliensis from localized cutaneous leishmaniasis (LCL) and mucocutaneous leishmaniasis (MCL) patients, L. (V.) guyanensis, L. (V.) shawi, L. (V.) lainsoni and L. (V.) naiffi from LCL patients only, in cultured BALB/c mice peritoneal macrophage, as well as the production of NO by the infected cells. The infectivity of parasites was expressed by the infection index and, the nitric oxide (NO) production in the macrophage culture supernatant was measured by the Griess method. It was found that L. (V.) braziliensis from MCL, the more severe form of disease, showed the highest (p <= 0.05) infection index (397), as well as the lowest NO production (2.15 mu M) compared with those of other species. In contrast, L. (V.) naiffi which is less pathogenic for the human showed the lowest infection index (301) and the highest NO production (4.11 mu M). These results demonstrated a negative correlation between the infectivity and the ability of these parasites to escape from the microbicidal activity of the host cell.