Obesity, bariatric surgery and oxidative stress / Obesidade, cirurgia bariátrica e estresse oxidativo

Summary Introduction: Obesity refers to the accumulation of fatty tissues and it favors the occurrence of oxidative stress. Alternatives that can contribute to body weight reduction have been investigated in order to reduce the production of reactive oxygen species responsible for tissue damage. The aim of the current study was to assess whether the oxidant and antioxidant markers of obese women before and after bariatric surgery were able to reduce oxidative damage. Method: We have assessed 16 morbidly obese women five days before and 180 days after the surgery. The control group comprised 16 non-obese women. Levels of thiobarbituric acid-reactive substances, carbonylated proteins, reduced glutathione and ascorbic acid were assessed in the patients' plasma. Results: Levels of lipid peroxidation and protein carbonylation in the pre-surgical obese women were higher than those of the controls and post-surgical obese women. Levels of reduced glutathione in the pre-surgical obese women were high compared to the controls, and declined after surgery. Levels of ascorbic acid fell in the pre--surgical obese women compared to the control and post-surgical obese women. Conclusion: Body weight influences the production of reactive oxygen species. Bariatric surgery, combined with weight loss and vitamin supplementation, reduces cellular oxidation, thus reducing tissue damage.

Resumo Introdução: Na obesidade, verifica-se um acúmulo de tecido adiposo, o que favorece a ocorrência de estresse oxidativo. A fim de diminuir a produção das espécies reativas que levam a danos teciduais, buscam-se alternativas que contribuam para a redução do peso corporal. Este estudo avaliou se os marcadores oxidantes e antioxidantes de obesas antes e após cirurgia bariátrica reduziram o dano oxidativo. Método: Foram avaliadas 16 mulheres obesas mórbidas cinco dias antes e 180 dias após o procedimento cirúrgico. O grupo controle constituiu-se de 16 mulheres não obesas. Os níveis das substâncias reativas ao ácido tiobarbitúrico, das proteínas carboniladas, da glutationa reduzida e do ácido ascórbico foram avaliados no plasma dessas pacientes. Resultados: Os níveis de lipoperoxidação e da carbonilação de proteínas nas obesas pré-cirúrgicas eram mais elevados quando comparados ao controle e às obesas pós-cirúrgicas; os níveis de glutationa reduzida eram maiores nas obesas pré-cirúrgicas em comparação ao controle e diminuíram após a cirurgia; os níveis de ácido ascórbico eram menores nas obesas pré-cirúrgicas em relação ao controle e às obesas pós-cirúrgicas. Conclusão: Observou-se que a massa corporal influenciou na produção das espécies reativas. A cirurgia bariátrica, somada à perda de peso e à suplementação vitamínica, diminui a oxidação celular e, com isso, reduz os danos teciduais.

Bioassessment using benthic macroinvertebrates of the water quality in the Tigreiro river, Jacuí Basin - doi: 10.4025/actascibiolsci.v35i4.18934

This study aimed to evaluate the water quality in the Tigreiro river, Jacuí river Basin, using different approaches. Benthic macroinvertebrates were sampled in July 2010 (winter) and February 2011 (summer) at five sites. In this study were analyzed: microbiological, physical and chemical variables, benthic macroinvertebrates richness and diversity, rapid ecological assessment protocol and benthic biotic indices (% EPT, BMWP-IAP, ASPT, SOMI). A total of 5,852 individuals were collected belonging to 31 taxa of three Phyla: Annelida, Mollusca and Arthropoda. Chironomidae was the most abundant taxon (63.70%). A reduction in richness, diversity H and evenness J was observed from the initial stretches to the end stretches of Tigreiro river. The use of different approaches showed that sites in the rural area were less altered. The Tigreiro river was strongly impacted, mainly due to discharge of domestic effluents in the urban area, and the combination of different metrics was useful to detect impacted sites and the consequence for the water quality.

Bioassessment using benthic macroinvertebrates of the water quality in the Tigreiro river, Jacuí Basin / Bioavaliação por macroinvertebrados bentônicos da qualidade da água no rio Tigreiro, Bacia do Jacuí

This study aimed to evaluate the water quality in the Tigreiro river, Jacuí river Basin, using different approaches. Benthic macroinvertebrates were sampled in July 2010 (winter) and February 2011 (summer) at five sites. In this study were analyzed: microbiological, physical and chemical variables, benthic macroinvertebrates richness and diversity, rapid ecological assessment protocol and benthic biotic indices (% EPT, BMWP'-IAP, ASPT, SOMI). A total of 5,852 individuals were collected belonging to 31 taxa of three Phyla: Annelida, Mollusca and Arthropoda. Chironomidae was the most abundant taxon (63.70%). A reduction in richness, diversity H' and evenness J' was observed from the initial stretches to the end stretches of Tigreiro river. The use of different approaches showed that sites in the rural area were less altered. The Tigreiro river was strongly impacted, mainly due to discharge of domestic effluents in the urban area, and the combination of different metrics was useful to detect impacted sites and the consequence for the water quality.

O objetivo deste estudo foi avaliar a qualidade de água do rio Tigreiro, bacia do rio Jacuí, pelo uso de diferentes abordagens. Macroinvertebrados bentônicos foram coletados em julho/2010 (inverno) e fevereiro/2011 (verão) em cinco pontos. Neste estudo foram analisados: variáveis microbiológicas, físicas e químicas, riqueza e diversidade de macroinvertebrados bentônicos, protocolo de avaliação ambiental rápida e índices bióticos de bentos (% EPT, BMWP'-IAP, ASPT, SOMI). Foram coletados 5.852 indivíduos pertencentes a 31 taxa de três Filos: Annelida, Mollusca e Arthropoda. Chironomidae foi o taxon dominante (63,70%). A redução de riqueza, diversidade H' e uniformidade J' ocorreram da porção inicial em direção à porção final do rio Tigreiro. O uso das diferentes abordagens mostrou que os pontos da área rural foram menos modificados. O rio Tigreiro apresentou-se fortemente impactado, principalmente pela descarga de esgotos domésticos na área urbana e o uso de diferentes métricas foi útil para detectar locais impactados e suas consequências para a qualidade de água.

Programa de detección de neoplasias colorrectales en población mayor de 50 años / A screening program for colorectal cancer in Chilean subjects aged fifty years or more

Background: Mortality from colorectal cancer (CCR) in Chile has nearly doubled over the past 15 years. International studies have shown that CCR screening programs based on fecal occult blood test (FOBT) reduce CCR mortality. Aim: To analyze the results from a CCR screening model in people over 50 years. Material and Methods: Between 2007 and 2009, a prospective multicenter study was performed in seven major Chilean cities. FOBT using an immunological method, was measured in asymptomatic subjects aged 50 years or more, without risk factors. In patients with a positive FOBT, with symptoms or with family risk factors, a colonoscopy was indicated. Results: A total of 6348 subjects were assessed, FOBT was performed in 4938 of them, with a compliance of 77%. The result was positive in 9.6%. A total of 2359 colonoscopies were ordered, with an overall compliance of 50.1%. Of the 1184 colonoscopies performed, adenomas and high risk adenomas were found in 304 (26%) and 75 (6%) patients, respectively. Thirteen patients were diagnosed with stage I and IICCR. Three of these lesions were excised endoscopically and 10 surgically. The detection rate of polyps, high risk adenomas and cancer was 75, 12 and 2 per 1000 screened individuals, respectively. Conclusions: This program allowed the early detection of an important number of high risk colon lesions, and all patients with CCR were diagnosed at early stages.

Tiflitis isquémica gangrenosa simulando apendicitis aguda / Ischemic gangrenous tiphlitis simulating acute appendicitis

Se presenta un caso de tiflitis isquémica gangrenosa, en un paciente con enfermedad vascular visceral ATE, cuyas manifestaciones clínicas y de laboratorio fueron similares a las de una apendicitis aguda y que requirió de hemicolectomía derecha