Chronic Stress Improves NO- and Ca2+ Flux-Dependent Vascular Function: A Pharmacological Study / Estresse Crônico Melhora a Função Vascular Dependente de NO e Fluxo De Ca2+: Um Estudo Farmacológico

Background: Stress is associated with cardiovascular diseases. Objective: This study aimed at assessing whether chronic stress induces vascular alterations, and whether these modulations are nitric oxide (NO) and Ca2+ dependent. Methods: Wistar rats, 30 days of age, were separated into 2 groups: control (C) and Stress (St). Chronic stress consisted of immobilization for 1 hour/day, 5 days/week, 15 weeks. Systolic blood pressure was assessed. Vascular studies on aortic rings were performed. Concentration-effect curves were built for noradrenaline, in the presence of L-NAME or prazosin, acetylcholine, sodium nitroprusside and KCl. In addition, Ca2+ flux was also evaluated. Results: Chronic stress induced hypertension, decreased the vascular response to KCl and to noradrenaline, and increased the vascular response to acetylcholine. L-NAME blunted the difference observed in noradrenaline curves. Furthermore, contractile response to Ca2+ was decreased in the aorta of stressed rats. Conclusion: Our data suggest that the vascular response to chronic stress is an adaptation to its deleterious effects, such as hypertension. In addition, this adaptation is NO- and Ca2+-dependent. These data help to clarify the contribution of stress to cardiovascular abnormalities. However, further studies are necessary to better elucidate the mechanisms involved in the cardiovascular dysfunction associated with stressors. (Arq Bras Cardiol. 2014; [online].ahead print, PP.0-0) .

Fundamento: Estresse está associado com complicações cardiovasculares. Objetivos: O objetivo do presente estudo foi avaliar se o estresse crônico induz alterações vasculares, e se essas alterações são dependentes de óxido nítrico (NO) e Ca2+. Métodos: Ratos machos Wistar com 30 dias de idade foram separados em 2 grupos: controle (C) e Estresse (St). Utilizou-se estresse crônico de imobilização por 1 hora/dia, 5 dias/semana, 15 semanas. Pressão arterial sistólica foi avaliada. A função vascular foi avaliada em anéis aórticos. Curvas de concentração-efeito foram realizadas para noradrenalina, na presença de L-NAME ou prazosina, cloreto de potássio (KCl), acetilcolina e nitroprussiato de sódio. Também foi efetuado um estudo para avaliação para fluxo de Ca2+. Resultados: Estresse crônico induziu hipertensão e resposta vascular diminuída para noradrenalina e KCl e aumentada para acetilcolina. A pré-incubação com L-NAME eliminou a diferença para noradrenalina. A resposta contrátil vascular para Ca2+ foi reduzida em animais estressados. Conclusão: Nossos dados sugerem que a resposta vascular ao estresse crônico seria uma adaptação aos efeitos deletérios do estresse, incluindo a hipertensão. Além disso, esses mecanismos adaptativos dependem de liberação de NO e fluxo de Ca2+. Esses resultados ajudam a esclarecer os mecanismos envolvidos nas alterações cardiovasculares associadas ao estresse. Entretanto, mais estudos são necessários para a melhor compreensão desses mecanismos. .

Not Just for Tobacco Users Anymore!!! The Emerging Evidence of Human Papilloma Virus: An Overview.

Head and neck squamous cell carcinoma (HNSCC) have a broad and varying rate of incidence and mortality around the world. Tobacco smoking and chewing, alcohol consumption are the main etiological agents for HNSCC and have been estimated to account for the majority of disease burden worldwide. Over the past 20 years, there has been an increasing awareness about the human papilloma virus (HPV), the necessary cause of cancer of the cervix that has been etiologically linked with oropharyngeal cancer. Often diagnosed at a late stage this subset of squamous cell carcinoma of the head and neck has an affi nity for the oropharynx and tends to show low diff erentiation histopathologically and better prognosis regardless of the treatment strategy. Th e HPV belongs to the papillomavaviridiae group of virus which can infect the mucosal and cutaneous epithelia in a species-specifi c manner inducing cellular proliferation. Th e HPV can cause active subclinical infection without clinical signs or can also cause clinical infection that can lead to benign, potentially malignant or malignant lesions. Hence, this overview attempts to focus on the relevant characteristics of HPV and its role in oropharyngeal cancer.

Smokeless tobacco use in Pakistan and its association with oropharyngeal cancer

Smokeless tobacco [ST], wtclefy used in Pakistan, poses a high risk for oral cancer. Our hospital-based data illustrate that oropharyngeal cancer [9.9%] is the second leading malignancy after breast cancer [16.1%], and is significantly higher than in other Member States of the World Health Organization's Eastern Mediterranean Region. Urdu-speaking communities had a proportionately higher rate of oropharyngeal cancer [20.4%], followed by Balochis [19.9%], Sindhis [16.8%], Punjabis [11.7%] and Pashtuns [9.6%]. Association of oropharyngeal cancer with ST use was four times higher relative to no history of tobacco use after adjusting for age, ethnicity and gender. Our findings also show a predominance of this cancer among males relative to females and one-third of the reported cases occurred among individuals under 40 years. These findings have significant social impact, indicating the need for urgent intervention against the use of ST

Micronucleus investigation of alcoholic patients with oral carcinomas

The micronucleus test (MN) is used as an indicator of genotoxic exposition, since it is associated with chromosome aberrations. An increased mutation rate in oral squamous cells, indicated by an increased MN frequency, is also related to the development of oral carcinomas. We evaluated the frequencies of MN and other metanucleated anomalies in the buccal squamous cells of 30 alcoholics with oral or oropharyngeal carcinomas, and compared them to a control group of abstinent health individuals. Microscopic examination was made of 2000 cells per individual from each of three distinct areas of the mouth: around the lesion (A), opposite to the lesion (B) and in the upper gingival-labial gutter (C); C was used as a control region because of low tumor frequency. There was a seven-fold increase in MN frequency in region B, a three-fold increase in region A and a two-fold, though nonsignificant, increase in C; indicating a gradient of frequencies towards carcinogenesis: C ® A ® B. Comparisons of frequencies of various types of metanucleated cells: binucleated, karyorrhexis (KR), karyolysis (KL) and broken egg (BE) in patients and controls showed, with few exceptions, highly significant differences. This gave us a better understanding of the dynamics of this squamous epithelium, supporting a more efficient biomonitor based on these various metanucleated anomalies: the repair index . Also, the apparently contradictory results from regression analysis revealed that the MN frequency decreased with age and alcohol consumption, probably because of slow cell proliferation, and consequently led to a loss of homeostasis due to aging. In addition, in the analysis of nonparametric variables only one CAGE question was significant, confirming the effect of alcohol. In conclusion, the MN test and the repair index could be used for monitoring clinical evolution, by means of intra- and inter-individual cellular comparisons, in subjects with healed or surgically removed tumors or leukoplastic lesions, after chemo- or radiotherapeutic treatments.

Controle do tabagismo: um desafio

Utiliza os dados apresentados pelos coordenadores de programas contra o fumo na 3ª Reuniäo Brasileira de Programas de Combate ao Fumo, realizada em Salvador no ano de 1989. Propöe estratégias e açöes a serem desenvolvidas pelos órgäos envolvidos em atividades anti-tabágicas. Os dados adicionais, coletados posteriormente pelos editores, complementam este perfil do controle do tabagismo no país