Célia Maria Machado Barbosa de Castro

Effects of Nasal Continuous Positive Airway Pressure Treatment on Oxidative Stress and Adiponectin Levels in Obese Patients with Obstructive Sleep Apnea

Background: Obesity and obstructive sleep apnea (OSA) are both associated with the prevalence of major cardiovascular illnesses and certain common factors they are considered responsible for, such as stress oxidative increase, sympathetic tonus and resistance to insulin. Objective: The aim of the present study was to compare the effect of continuous positive airway pressure (CPAP) on oxidative stress and adiponectin levels in obese patients with and without OSA. Methods: Twenty-nine obese patients were categorized into 3 groups: group 1: 10 individuals without OSA (apnea-hypopnea index, AHI ≤5) who did not have OSA diagnosed at polysomnography; group 2: 10 patients with moderate to severe OSA (AHI ≧20) who did not use CPAP; group 3: 9 patients with moderate to severe OSA (AHI ≧20) who used CPAP. Results: Group 3 showed significant differences before and after the use of CPAP, in the variables of diminished production of superoxide, and increased nitrite and nitrate synthesis and adiponectin levels. Positive correlations were seen between the AHI and the superoxide production, between the nitrite and nitrate levels and the adiponectin levels, between superoxide production and the HOMA-IR, and between AHI and the HOMA-IR. Negative correlations were found between AHI and the nitrite and nitrate levels, between the superoxide production and that of nitric oxide, between the superoxide production and the adiponectin levels, between AHI and the adiponectin levels, and between the nitrite and nitrate levels and the HOMA-IR. Conclusions: This study demonstrates that the use of CPAP can reverse the increased superoxide production, the diminished serum nitrite, nitrate and plasma adiponectin levels, and the metabolic changes existing in obese patients with OSA.

Effect of stress on the production of O2− in alveolar macrophages

Abstract Alveolar macrophages (AM) of male rats (200–250 g), stressed or not, were evaluated with relationship to superoxide production (SP). Plasma levels of corticosterone were measured. The control group showed larger SP than the stressed group in all intervals of time. Exposure in vitro of AM to a synthetic glucocorticoid for 40 min (the same time of restraint stress) inhibits SP. Therefore, it seems under stress situations there is an increase of plasma levels of corticosterone and a decrease of SP in AM after stimulation with PMA. O 2 − is a potent microbicide and its reduction could cause the loss of microbicidal activity of AM.

Shrimp Waste Extract and Astaxanthin: Rat Alveolar Macrophage, Oxidative Stress and Inflammation

UNLABELLED Astaxanthin is a carotenoid known to have antioxidant and antiinflammatory properties. This study examined if shrimp astaxanthin modulates the production of superoxide (O(-)(2)), nitric oxide (NO), and tumor necrosis factor-α (TNF-α) in rat alveolar macrophages. The oxidative effect was induced by phorbol myristate acetate and lipopolysacharide. The treatment was compared with superoxide dismutase, butylated hydroxytoluene, commercial astaxanthin, N-nitric-L-arginine methyl ester and L- canavanine, all administered as a 43.5-μg/mL dose in the presence of 1% EtOH/0.5% DMSO. All treatments maintained cell viability, as observed in the MTT assay, and shrimp extract increased the viable alveolar macrophages to 168%. Shrimp extract and commercial astaxanthin showed a suppressive effect on the generation of both free radicals O(-)(2) and NO, while purified shrimp astaxanthin was specific to NO. TNF-α secretion was correlated with NO production. However, in this correlation, the shrimp extract completely inhibited TNF-α. In the light of these findings, the antioxidant action demonstrated in this study suggests that the shrimp extract could be considered as a promising source of bioactive substances with antioxidant and anti-inflammatory activity. PRACTICAL APPLICATION The hydrolysis process of shrimp waste generates bioactive products that add economic value to shrimp processing, mainly because they may have applications in nutraceutical and animal feed industry.

Cytotoxicity of current adhesive systems: In vitro testing on cell cultures of primary murine macrophages

OBJECTIVES The aim of this study was to evaluate, in vitro, the potential cytotoxicity of dentinal adhesives on alveolar macrophages of Wistar rats, after diffusion through dentin. METHODS The cytotoxicity of adhesives [single bond plus (SB), clearfil SE bond (CF) and Xeno V (XE)] applied to the occlusal surface of human dentin disks adapted to a dentin barrier test device were analyzed. The sets placed on a monolayer of cells were incubated for 24, 48 and 72h. Culture medium and Escherichia coli lipopolysaccharides (LPS) were used as negative and positive controls, respectively. Cellular cytotoxicity was evaluated by observing the cell survival rate (MTT assay) and nitric oxide production (NO). The data were analyzed by one-way factorial ANOVA and Tukeys and Tamhanes paired comparisons T2 (α=0.05). RESULTS All the adhesive systems reduced the percentage of live cells by over 50%, compared with the control group. Within the same period of time, there was a statistically significant difference between the adhesives and LPS compared with the negative control group. SB presented a statistically significant difference between 24h and 72h, and XE between 48h and 72h. The quantity of NO produced in 24h did not differ statistically between the NC and adhesive groups. After 48h there was a significant difference between SB/CF and XE/NC. At 72h only CF showed a significant difference from each of the other groups. LPS differed statistically from all the other groups at all the evaluation times. SIGNIFICANCE Components of the adhesives tested may permeate the dentin in sufficient concentrations to cause death and damage to cell metabolism in the alveolar macrophages of rats, which indicates potential cytotoxicity to pulpal cells.

Efeitos da deficiência de cobre, zinco e magnésio sobre o sistema imune de crianças com desnutrição grave

OBJECTIVE: To report the effects of the deficiency of copper, zinc and magnesium on the immune system of severely malnourished children. DATA SOURCE: A literature review was performed by consulting the databases Pubmed Medline, Lilacs and SciELO, using the descriptors: child malnutrition, copper, zinc, magnesium and immune system. Representative studies published during the last decade were chosen. DATA SYNTHESIS: Micronutrients are essential organic compounds. Besides their regulatory function, the minerals act on the modulation of the immune response. Their deficiency may be due to inadequate intake or associated with specific diseases. When combined with malnutrition, a multimineral deficiency can cause immune dysfunction and increased susceptibility to infections, altering the effectiveness of therapeutic interventions. Copper, zinc and magnesium act as co-factors of both enzymes responsible for several metabolic activities and associated to the innate and acquired immune response. These minerals also play an important role in the maturation of lymphoid tissues and cells. Their deficiency causes neutropenia and lymphopenia, decreasing the immunocompetence. CONCLUSIONS: Deficits of serum copper, zinc and magnesium affect the function of the immune system, leading to immunosuppression. The replacement of these elements in the management of severe malnutrition, as recommended by the World Health Organization, is essential, since such changes may be reversible.

Autotransplant of spleen tissue in children with schistosomiasis: evaluation of splenic function after splenosis.

Autotransplantation of spleen tissue has been done, in the past ten years, in children with schistosomiasis mansoni with bleeding varices. The purposes of this investigation were: (1) to study the morphology and function of the remnant spleen tissue; (2) to quantify the production of tuftsin; and (3) to assess the immune response to pneumococcal vaccine of these patients. Twenty three children, who underwent splenectomy and autologous implantation of spleen tissue into the greater omentum were included in this investigation. The average postoperative follow-up is five years. Splenosis was proved by colloid liver-spleen scans. Search for Howell-Jolly bodies assessed the filtration function. Tuftsin and the titer of pneumococcal antibodies were quantified by ELISA. Splenosis was evident in all children; however, it was insufficient in two. Howell-Jolly bodies were found only in these two patients. The mean tuftsin serum concentration (335.0 +/- 29.8 ng/ml) was inside the normal range. The immune response to pneumococcal vaccination was adequate in 15 patients; intermediate in four; and inadequate in four. From the results the following conclusions can be drawn: splenosis was efficient in maintaining the filtration splenic function in more than 90% and produced tuftsin inside the range of normality. It also provided the immunologic splenic response to pneumococcal vaccination in 65% of the patients of this series.

Physical Training Attenuates the Stress-Induced Changes in Rat T-Lymphocyte Function

Backgorund/Aims: Modulations in the immune function by stress are a well-known phenomenon. Acute restraint stress may induce impaired T-lymphocyte responses. Moderate physical training is associated with beneficial effects on immunological functions. We investigated the effects of a moderate physical training on T-lymphocyte function in rats submitted to acute restraint stress. Methods: Thirty male Wistar rats weighing 210–226 g were randomly divided into four groups: non-trained rats (NT, n = 7), and non-trained rats submitted to stress (NT + S, n = 8); trained rats (T, n = 7), and trained rats submitted to stress (T + S, n = 8). Trained rats were submitted to a program of moderate running over a period of 8 weeks. Rats subjected to restraint stress were kept immobilized in glass cylinders (8 cm in diameter and 24 cm long) during 60 min. Plasma corticosterone concentration, peripheral blood leukocyte number, indicators of apoptosis of T lymphocytes in blood and lymphoid organs, and mitogen-induced proliferation of T lymphocytes in lymphoid organs were evaluated. Results: Acute stress exposure raised plasma corticosterone concentration (p < 0.001), but not in previously trained animals. Restraint stress induced an increase in the percentage of lymphocytes in apoptosis, and a decrease in the concanavalin-A-induced proliferation of lymphocytes from the thymus and lymph nodes, and an increase in lymphocytes of the spleen. Neither of these alterations was observed in trained animals submitted to acute restraint stress. Conclusions: Our data confirm that acute restraint stress is associated with changes in T-lymphocyte function. Moreover, moderate physical training attenuates the effects of acute stress by a mechanism that involves the hypothalamic-pituitary-adrenal axis and an increase in tolerance of leukocytes.

Resposta terapêutica e inflamatória de ratos com peritonite secundária submetidos ao uso tópico de ampicilina/sulbactam

OBJETIVOS: A peritonite aguda representa uma importante causa de sepsis e obito nas unidades de terapia intensiva e cirurgia. Classicamente o seu tratamento deve incluir: a administracao sistemica de antibioticos, a remocao mecânica dos contaminantes e a restauracao da integridade gastrintestinal. A utilizacao de antibioticos diretamente na cavidade peritoneal e controversa. Estudo com o objetivo de avaliar o uso terapeutico, intraperitoneal da ampicilina associada ao sulbactam. METODOS: foram mensurados os niveis plasmaticos do oxido nitrico, bem como a contagem de eosinofilos, linfocitos, monocitos e neutrofilos no sangue e no lavado peritoneal, utilizando-se modelo de peritonite em ratos (ligadura-transfixacao cecal). Vinte quatro ratos Wistar, machos, foram divididos em quatro grupos de seis animais, assim distribuidos: grupo A: metodo de inducao de peritonite - soltura da ligadura + tratamento com soro fisiologico; grupo B: metodo de inducao de peritonite + soltura da ligadura + tratamento com soro fisiologico acrescido de ampicilina / sulbactam; grupo C: metodo de inducao de peritonite + soltura da ligadura-transfixacao cecal; e grupo D: laparatomia para realizacao de lavado peritoneal mais coleta de sangue. A ligadura-transfixacao do cecum permaneceu por 24 horas, antes do tratamento instaurado. Foi realizada uma relaparotomia nos 18 ratos com coleta de liquido de lavado peritoneal e sangue. Foram dosados os niveis plasmaticos de oxido nitrico e determinado o numero de eosinofilos, linfocitos, monocitos e neutrofilos no sangue e no lavado peritoneal. RESULTADOS: Nao ocorreu diferenca estatisticamente significante (p > 0,05) nos niveis de oxido nitrico, bem como no numero de eosinofilos, linfocitos, monocitos e neutrofilos no sangue e no lavado peritoneal, entre os grupos. CONCLUSAO: Neste estudo, concluiu-se que: a utilizacao de ampicilina associada a sulbactam por via intraperitoneal nos ratos com peritonite fecal: nao modificou a sobrevida; nao alterou os niveis plasmaticos de oxido nitrico; nao alterou a contagem de eosinofilos, linfocitos, monocitos e neutrofilos tanto no sangue como no lavado peritoneal.

Depressive symptoms, inflammatory markers and body composition in elderly with and without chronic obstructive pulmonary disease (COPD)

UNLABELLED Our aim was to assess the relationships between cortisol, interleukin-2 (Il-2) and tumor necrosis factor-α (TNF-α) levels in elderly with and without COPD presenting with or without depressive symptoms. Forty COPD patients and 53 elderly individuals with no COPD took part in the study. Depressive symptoms (Geriatric Depression Scale=GDS-15), IL-2 and TNF-α, serum cortisol, number of comorbidities, smoking habits and body composition were evaluated. The prevalence of depressive symptoms was higher in COPD group. The number of comorbidities was higher in patients with depressive symptoms. No differences were found between IL-2, TNF-α and cortisol levels, years of smoking and smoked pack-years in the groups. The COPD group obtained lower body mass index (BMI) and fat content and higher fat free mass index as well as greater nutritional depletion. CONCLUSIONS Depressive symptoms as well as fat and lean body composition, due to preserved BMI in those with nutritional depletion, must be investigated.

In vitro potential cytotoxicity of an adhesive system to alveolar macrophages

The purpose of this study was to evaluate the potential cytotoxicity of Adper Single Bond 2 (SB) simplified etch-and-rinse adhesive system in alveolar macrophage cultures, as a function of the post-polymerization time and duration of immersion in the culture medium for preparation of extracts, by observing the levels of nitric oxide (NO) release and cell survival rate (MTT assay). Wistar rat alveolar macrophages were exposed to 200 microL of extracts obtained from 24- or 72-h immersion of adhesive samples in culture medium (RPMI), immediately or 24 h after polymerization. Fresh RPMI and E. coli lipopolysaccharides were used as negative and positive controls, respectively. The cells were placed in a humidified incubator for 24 h. The results were analyzed by the Students-t test (alpha=5%). The amount of NO produced and viable cells were significantly different (p<0.05) between the experimental and the control groups, showing that, irrespective of the post-polymerization time and duration of immersion in the culture medium, the adhesive system caused intense cytotoxicity to the macrophages. The cytotoxic effects were not statistically different (p<0.05) among the experimental groups. In conclusion, chemical components released from SB in aqueous environment were highly toxic to cell culture and thus an inflammatory pulpal response should be considered during the clinical application of dental adhesives.