409 resultados para Pollution induced corrosion


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Several differences have been described between neonatal and adult immune responses. The predisposition in early life to Th2-type response or tolerance makes it a susceptible period for infections and allergic sensitization. The aim of this work was to evaluate the effects of CpG-containing oligodeoxynucleotides on neonatal and adult immunization with ovalbumin and Blomia tropicalis extract and compare the CpG effects on B and T cells of neonatal and adult mice. Mice that received CpG showed reduced immunoglobulin E (IgE) antibody production in both neonatal and adult periods, in parallel to increased IgG2a antibody levels. We observed that spleen cells of mice that received CpG in early life produced increased amounts of interferon-gamma upon anti-CD3 stimulation. Negative regulation of IgE response was more pronounced in adult than neonate mice; further, CpG decreased anaphylactic antiovalbumin IgG1 only in adults. Also, an upregulation of toll-like receptor 9 expression was detected in adult B cells, but not in neonatal, upon CpG stimuli. Neonatal B cells showed enhanced interleukin (IL)-10 expression and decreased IL-6 levels than adult B cells in response to CpG. When we analyzed in vitro activation of CD4+ T cells, an increased expression of B7 molecules on T cells in neonates was suppressed by CpG. Altogether, we verified qualitative and quantitative evidences regarding CpG effect on neonatal and adult allergens immunizations, which points to the importance of understanding neonatal immune system to establish immunomodulatory strategies for prevention of allergic diseases.

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Gemcitabine is a chemotherapy agent that may cause unpredictable side effects. In this report, we describe a fatal gemcitabine-induced pulmonary toxicity in a patient with gallbladder metastatic adenocarcinoma. A 72-year-old patient was submitted to an elective laparoscopic cholecystectomy, and a tubular adenocarcinoma in the gallbladder was incidentally diagnosed. CT scan and ultrasound before the surgery did not show any tumor. After the surgery a Pet scan was positive for a hot-spot in the left colon. The colonic lesion was conveniently removed and the histology evaluation confirmed the diagnosis of adenocarcinoma tubular. The patient was then submitted to three sections of 1,600 mg/m(2) of gemcitabine with intervals of 1 week. Three weeks later he developed severe respiratory distress. A helicoidal CT scan showed diffuse and severe interstitial pneumonitis, and lung biopsy confirmed accelerated usual interstitial pneumonia consistent with drug-induced toxicity. The patient presented unfavorable evolution with progressive worsening of respiratory function, hypotension, and renal failure. He died 1 month later in spite of methylprednisolone pulse therapy, large spectrum antimicrobial therapy, and full support of respiratory, hemodynamic and renal systems. Gemcitabine-induced pulmonary toxicity is usually a dramatic condition. Physicians should suspect pulmonary toxicity in patients with respiratory distress after gemcitabine chemotherapy, mainly in elderly patients.

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RAMOS, D. S. C. R. OLIVO. F. D. QUIRINO SANTOS LOPES, A. C. TOLEDO, M. A. MARTINS, R. A. LAZO OSORIO. M. DOLHNIKOFF, W. RIBEIRO, and R. R VIEIRA. Low-Intensity Swimming Training Partially Inhibits Lipopolysaccharide-Induced Acute Lung Injury. Med. Sci. Sports Exerc.. Vol. 42, No. 1, pp. 113-119, 2010. Background: Aerobic exercise-decreases pulmonary inflammation and remodeling in experimental models of allergic asthma. However, the effects of aerobic exercise oil pulmonary inflammation of nonallergic Origin, such as in experimental models of acute long injury induced by lipopolysaccharide (LPS), have not been evaluated. Objective: The present study evaluated file effects of aerobic exercise in a model of LPS-induced acute lung injury. Methods: BALB/c mice were divided into four groups: Control, Aerobic Exercise, LPS, and Aerobic Exercise + LPS. Swimming tests were conducted at baseline and at 3 and 6 wk. Low-Intensity swimming training was performed for 6 wk, four times per week, 60 min per session. Intranasal LPS (1 mg.kg(-1) (60 mu g per mouse)) was instilled 24 It after the last swimming physical test in the LPS and Aerobic Exercise + LPS mice, and the animals were studied 24 It after LPS instillation. Exhaled nitric oxide, respiratory mechanics, total and differential cell Counts in bronchoalveolar lavage, and lung parenchymal inflammation and remodeling were evaluated. Results: LPS instillation resulted in increased levels of exhaled nitric oxide (P < 0.001), higher numbers of neutrophils in file bronchoalveolar lavage (P < 0.001) and in the lung parenchyma (P < 0.001), and decreased lung tissue resistance (P < 0.05) and volume proportion of elastic fibers (P < 0.01) compared with the Control group. Swim training in LPS-instilled animals resulted in significantly lower exhaled nitric oxide levels (P < 0.001) and fewer nelltrophils in the bronchoalveolar lavage (P < 0.001) and the lung parenchyma (P < 0.01) compared with the LPS group. Conclusions: These results Suggest that low-intensity swimming training inhibits lung neutrophilic inflammation, but not remodeling and impaired lung mechanics, in a model of LPS-induced acute lung injury.

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The aim of this study was to test the hypothesis that bone marrow mononuclear cell (BMDMC) therapy led an improvement in lung mechanics and histology in endotoxin-induced lung injury. Twenty-four C57BL/6 mice were randomly divided into four groups (n = 6 each). In the acute lung injur;y (ALI) group, Escherichia coli lipopolysaccharide (LPS) was instilled intratracheally (40 mu g, IT), and control (C) mice received saline (0.05 ml, IT). One hour after the administration of saline or LPS, BMDMC (2 x 10(7) cells) was intravenously injected. At day 28, animals were anesthetized and lung mechanics [static elastance (E(st)), resistive (Delta P(1)), and viscoelastic (Delta P(2)) pressures] and histology (light and electron microscopy) were analyzed. Immunogold electron microscopy was used to evaluate if multinucleate cells were type II epithelial cells. BMDMC therapy prevented endotoxin-induced lung inflammation, alveolar collapse, and interstitial edema. In addition, BMDMC administration led to epithelial and endothelial repair with multinucleated type II pneumocytes. These histological changes yielded a reduction in lung E(st), Delta P(1), and Delta P(2) compared to ALI. In the present experimental ALI model, the administration of BMDMC yielded a reduction in the inflammatory process and a repair of epithelium and endothelium, reducing the amount of alveolar collapse, thus leading to an improvement in lung mechanics.

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Introduction: Recruitment maneuvers (RMs) seem to be more effective in extrapulmonary acute lung injury (ALI), caused mainly by sepsis, than in pulmonary ALI. Nevertheless, the maintenance of adequate volemic status is particularly challenging in sepsis. Since the interaction between volemic status and RMs is not well established, we investigated the effects of RMs on lung and distal organs in the presence of hypovolemia, normovolemia, and hypervolemia in a model of extrapulmonary lung injury induced by sepsis. Methods: ALI was induced by cecal ligation and puncture surgery in 66 Wistar rats. After 48 h, animals were anesthetized, mechanically ventilated and randomly assigned to 3 volemic status (n = 22/group): 1) hypovolemia induced by blood drainage at mean arterial pressure (MAP)approximate to 70 mmHg; 2) normovolemia (MAP approximate to 100 mmHg), and 3) hypervolemia with colloid administration to achieve a MAP approximate to 130 mmHg. In each group, animals were further randomized to be recruited (CPAP = 40 cm H(2)O for 40 s) or not (NR) (n = 11/group), followed by 1 h of protective mechanical ventilation. Echocardiography, arterial blood gases, static lung elastance (Est, L), histology (light and electron microscopy), lung wet-to-dry (W/D) ratio, interleukin (IL)-6, IL-1 beta, caspase-3, type III procollagen (PCIII), intercellular adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1 (VCAM-1) mRNA expressions in lung tissue, as well as lung and distal organ epithelial cell apoptosis were analyzed. Results: We observed that: 1) hypervolemia increased lung W/D ratio with impairment of oxygenation and Est, L, and was associated with alveolar and endothelial cell damage and increased IL-6, VCAM-1, and ICAM-1 mRNA expressions; and 2) RM reduced alveolar collapse independent of volemic status. In hypervolemic animals, RM improved oxygenation above the levels observed with the use of positive-end expiratory pressure (PEEP), but increased lung injury and led to higher inflammatory and fibrogenetic responses. Conclusions: Volemic status should be taken into account during RMs, since in this sepsis-induced ALI model hypervolemia promoted and potentiated lung injury compared to hypo-and normovolemia.

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Exposure to air pollution can elicit cardiovascular health effects. Children and unborn fetuses appear to be particularly vulnerable. However, the mechanisms involved in cardiovascular damage are poorly understood. It has been suggested that the oxidative stress generated by air pollution exposure triggers tissue injury. To investigate whether prenatal exposure can enhance oxidative stress in myocardium of adult animals, mice were placed in a clean chamber (CC, filtered urban air) and in a polluted chamber (PC, Sao Paulo city) during the gestational period and/or for 3 mo after birth, according to 4 protocols: control group-prenatal and postnatal life in CC; prenatal group-prenatal in PC and postnatal life in CC; postnatal group-prenatal in CC and postnatal life in PC; and pre-post group-prenatal and postnatal life in PC. As an indicator of oxidative stress, levels of lipid peroxidation in hearts were measured by malondialdehyde (MDA) quantification and by quantification of the myocardial immunoreactivity for 15-F2t-isoprostane. Ultrastructural studies were performed to detect cellular alterations related to oxidative stress. Concentration of MDA was significantly increased in postnatal (2.45 +/- 0.84 nmol/mg) and pre-post groups (3.84 +/- 1.39 nmol/mg) compared to the control group (0.31 +/- 0.10 nmol/mg) (p < .01). MDA values in the pre-post group were significantly increased compared to the prenatal group (0.71 +/- 0.15 nmol/mg) (p = .017). Myocardial isoprostane area fraction in the pre-post group was increased compared to other groups (p <= .01). Results show that ambient levels of air pollution elicit cardiac oxidative stress in adult mice, and that gestational exposure may enhance this effect.

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Millions of people worldwide are affected by anthropogenic air pollution derived from the combustion of fossil fuels. In this work, we tested the effects of fetal, lactation and post-weaning ambient air pollution exposure on total homocysteine (tHcy) concentrations and on a downstream pathway element, the plasma cysteine (Cys) concentration. Two similar exposure chambers (polluted and filtered chamber) were located near an area with heavy traffic in Sao Paulo, Brazil, and male Swiss mice were housed there from the pre-natal period until 3 months of age. Groups during fetal, lactation and adult periods of exposure were apportioned, and tHcy and Cys plasma concentrations were assessed when the animals were 3 months old. In our study, both the tHcy and Cys concentrations were decreased in groups that spent their final stage of life in polluted chambers, suggesting recent alterations in tHcy and Cys concentrations due to air pollution exposure. The possible relationship of these data with cardiovascular dysfunction is still a matter of controversy in animals; nevertheless, epigenetic mechanisms emerge as a possible issue to consider in the investigation of the link between air pollution and Hcy measurement. (C) 2009 Elsevier Inc. All rights reserved.

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Storage at low temperature is the most frequently used method to extend the shelf life of banana fruit, and is fundamental for extended storage and transport over long distances. However, storage and transport conditions must be carefully controlled because of the high susceptibility of many commercial cultivars to chilling injury. The physiological behavior of bananas at low temperatures has been studied to identify possible mechanisms of resistance to chilling injury. The aim of this work was to evaluate differences in the starch-to-sucrose metabolism of a less tolerant and susceptible (Musa acuminata, AAA cv. Nanicao) and a more tolerant (M. acuminata x Musa balbusiana, AAB, cv. Prata) banana cultivar to chilling injury. Fruits of these cultivars were stored in chambers at 13 degrees C for 15 d, at which point they were transferred to 19 degrees C, where they were left until complete ripening. The low temperature induced significant changes in the metabolism of starch and sucrose in comparison to fruit ripened only at 19 degrees C. The sucrose accumulation was slightly higher in cv. Prata, and different patterns of starch degradation, sucrose synthesis, activity and protein levels of the alpha-and beta-amylases, starch phosphorylase, sucrose synthase and sucrose phosphate synthase were detected between the cultivars. Our results suggest that starch-to-sucrose metabolism is likely part of the mechanism for cold acclimation in banana fruit, and the cultivar-dependent differences contribute to their ability to tolerate cold temperatures. (C) 2011 Elsevier B.V. All rights reserved.

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This report describes the case of a 41-year old woman in treatment for advanced colorectal cancer who developed severe bilateral blepharitis and trichomegaly after the second dose of cetuximab. Cetuximab-related eyelid toxicity has been described previously; however, its pathogenesis has not yet been clearly established.

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Fleet enemas are hypertonic solutions with an osmotic action and a high concentration of phosphate. When retained in the human body they have a great toxic potential, causing severe hydro-electrolyte disorders in children, especially in newborns. We report the case of a previously healthy 8-day-old newborn who needed neonatal intensive care treatment after the inadvertent administration of an osmotically active hypertonic phosphate enema. Taking into account that phosphate removal by peritoneal dialysis (PD) strongly depends on total dialysate turnover, we chose continuous flow PD (CFPD) as the treatment option, with a successful outcome. Clinical experience with this dialytic modality is limited to a few case reports in pediatric and adult patients. To the best of our knowledge, we report here the first description of CFPD in the setting of acute phosphate nephropathy in the neonatal period. The modality of PD described here has potential as an alternative management option as it is a highly efficient, methodologically simple, and low-cost method without any need for sophisticated equipment. Physicians and parents should be aware of the adverse effects of a hypertonic phosphate enema and should never use these medications in infants and newborns.

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High salt intake is a known cardiovascular risk factor and is associated with cardiac alterations. To better understand this effect, male Wistar rats were fed a normal (NSD: 1.3% NaCl), high 4 (HSD4: 4%), or high 8 (HSD8: 8%) salt diet from weaning until 18 wk of age. The HSD8 group was subdivided into HSD8, HSD8+HZ (15 mg.kg(-1).d(-1) hydralazine in the drinking water), and HSD8+LOS (20 mg.kg(-1).d(-1) losartan in the drinking water) groups. The cardiomyocyte diameter was greater in the HSD4 and HSD8 groups than in the HSD8+LOS and NSD groups. Interstitial fibrosis was greater in the HSD4 and HSD8 groups than in the HSD8+HZ and NSD groups. Hydralazine prevented high blood pressure (BP) and fibrosis, but not cardiomyocyte hypertrophy. Losartan prevented high BP and cardiomyocyte hypertrophy, but not fibrosis. Angiotensin II type 1 receptor (AT(1)) protein expression in both ventricles was greater in the HSD8 group than in the NSD group. Losartan, but not hydralazine, prevented this effect. Compared with the NSD group, the binding of an AT(1) conformation-specific antibody that recognizes the activated form of the receptor was lower in both ventricles in all other groups. Losartan further lowered the binding of the anti-AT(1) antibody in both ventricles compared with all other experimental groups. Angiotensin II was greater in both ventricles in all groups compared with the NSD group. Myocardial structural alterations in response to HSD are independent of the effect on BP. Salt-induced cardiomyocyte hypertrophy and interstitial fibrosis possibly are due to different mechanisms. Evidence from the present study suggests that salt-induced AT(1) receptor internalization is probably due to angiotensin II binding. J. Nutr. 140: 1742-1751, 2010.

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Objectives Microsatellite instability (MSI) induction by alkylating agent-based chemotherapy (ACHT) may underlie both tumor resistance to chemotherapy and secondary leukaemias in cancer patients. We investigated if ACHT could induce MSI in tumor-derived plasma-circulating DNA (pfDNA) and in normal peripheral blood mononuclear (PBMN) cells. We also evaluated if amifostine could interfere with this process in an in-vitro model. Methods MSI was determined in pfDNA, PBMN cells and urine cell-free DNA (ufDNA) of 33 breast cancer patients before and after ACHT. MCF-7 cells and PBMN from normal donors were exposed in vitro to melphalan, with or without amifostine. Results We observed at least one MSI event in PBMN cells, pfDNA or ufDNA of 87, 80 and 80% of patients, respectively. In vitro, melphalan induced MSI in both MCF-7 and normal PBMN cells. In PBMN cells, ACHT-induced MSI occurred together with a significant decrease in the expression of the DNA mismatch repair gene hMSH2. Amifostine decreased hMSH2 expression and also prevented MSI induction only in normal PBMN cells. Conclusions ACHT induced MSI in PBMN cells and in tumour-derived pfDNA. Because of its protective effect against ACHT induction of MSI in normal PBMN cells in vitro, amifostine may be a potential agent for preventing secondary leukaemias in patients exposed to ACHT.

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Purpose: alpha-Melanocyte stimulating hormone protects kidneys against ischemia and sepsis induced acute kidney injury in rodents. We examined the efficacy of a-melanocyte stimulating hormone analogue AP214 to protect against acute kidney injury in higher vertebrates. Materials and Methods: We performed a prospective, blinded, randomized, placebo controlled study in 26 pigs. Laparoscopic technique was used for left nephrectomy and to induce complete warm ischemia in the right kidney for 120 minutes. AP214 (200 mu g/kg intravenously) was administered daily on the day of surgery and for 5 days thereafter. Kidney function was measured for 9 days. We measured changes in serum creatinine, estimated glomerular filtration rate, serum C-reactive protein and urine interleukin-18. Results: In the placebo control and AP214 groups mean peak serum creatinine was 10.2 vs 3.92 mg/dl and the estimated glomerular filtration rate nadir was 22.9 vs 62.6 ml per minute per kg (each p = 0.001). Functional nadir occurred at 72 vs 24 hours in the control vs AP214 groups. Estimated glomerular filtration rate outcome on postoperative day 9 was 118 vs 156 ml per minute per kg in the control vs AP214 groups (p = 0.04). Conclusions: We noted a robust renoprotective effect of AP214. A similar AP214 effect may be observed in humans. Future research includes mechanistic studies in pigs and a phase II human clinical trial of AP214 in kidney transplant and partial nephrectomy populations.

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Menopause is recognized as a period of increased risk for coronary heart disease. Although the benefits of exercise training in lowering cardiovascular risk factors are well established, the risks and benefits of hormone therapy have been questioned. The purpose of the present study was to investigate the effects of estrogen therapy (HT) associated or not with exercise training (ET) in autonomic cardiovascular control in ovariectomized (OVX) rats. Female rats were divided into: control, OVX, OVX+HT, OVX+ET and OVX+HT+ET. HT was performed using a 0.25 mg 8-weeks sustained release pellet. Trained groups were submitted to an 8-week exercise training protocol on treadmill. Baroreflex sensitivity (BRS) was evaluated by heart rate responses to arterial pressure (AP) changes, and vagal and sympathetic tonus by pharmacological blockade. Ovariectomy induced an AP increase (123 +/- 2 mmHg vs. 108 +/- 2 mmHg), BRS impairment (similar to 69%), sympathetic activation (similar to 100%) and vagal tonus reduction (similar to 77%) compared to controls. HT or ET normalized the changes in parasympathetic tonus. However, only the association HT + ET was able to promote normalization of AP, BRS and sympathetic tonus, as compared to controls. These results indicate that ET induces cardiovascular and autonomic benefits in OVX rats under HT, suggesting a positive role of this association in the management of cardiovascular risk factor in postmenopausal women. (C) 2009 Elsevier Ireland Ltd. All rights reserved.

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The treatment of membranous lupus nephritis (MLN) is still controversial in the literature. We conducted a retrospective analysis of patients in two medical centers of Sao Paulo-Brazil in order to evaluate the clinical response in patients submitted to either a regimen with prednisone alone or to a double immunosuppressive regimen (prednisone plus cyclophosphamide or prednisone plus azathioprine). Methods: MLN female patients were enrolled in this retrospective study conducted from February 1999 to June 2007. Data were collected from the patients` medical charts. Race distribution was similar in both groups: Caucasian (72.3%) and Afro-Latin-American (27.7%). The prednisone regimen consisted of 1 mg/kg/day for 8 weeks and tapering until 0.1 mg/kg/day (n = 29). The double immunosuppressive treatment consisted of the same doses of prednisone plus monthly intravenous cyclophosphamide or azathioprine for 6 months (n = 24). Criteria for remission (complete and partial) and renal function loss as well as flare criteria followed those used in the literature. Results: There was no difference between the prednisone group and the double immunosuppressive group regarding age (33.2 +/- 9.4 vs. 29.1 +/- 9.1 y), estimated GFR (76.5 +/- 26.6 vs. 74.1 +/- 39.6 ml/min/1.73 m(2)), serum albumin (2.8 +/- 0.7 vs. 2.6 +/- 0.3 g/dl), positive ANA (87.5 vs. 90.0%), positive anti-dsDNA (47.6 vs. 44.0%), renal SLEDAI indices (6.6 +/- 2.6 vs. 7.0 +/- 3.1), follow-up time (71 +/- 46 vs. 62 +/- 45 months), as well as proteinuria (3.1 +/- 1.9 vs. 4.8 +/- 2.4 g/day) and number of non-nephrotic patients (6 in the prednisone group vs. 3 in the double immunosuppressive group). The prednisone group presented higher C3 values (85.2 +/- 31.5 vs. 62.3 +/- 41.6 U/ml, p = 0.04). Clinical and laboratory characteristics at 6 months and at last follow-up did not reveal any differences between treatment regimens. Renal survival after an 8-year follow-up did not differ in both groups (prednisone group 86.2% vs. double immunosuppressive group 75%), and patients in both groups showed a high rate of renal flares (prednisone group 51.7% vs. double immunosuppressive group 62.5%). Univariate analysis showed that only patient age predicted flares (r = -0.048, p = 0.04). Borderline significance was obtained for proteinuria analysis (p = 0.07). Adverse effects did not differ between the groups. Conclusions: A regimen of corticosteroids in MLN induced a high remission rate after 6 months. Both treatment regimens showed a high flare rate and age was the only predictive parameter (r = -0.048, p = 0.04). Renal survival after 8 years did not differ between the groups.