Ação genotóxica e antiproliferativa de Polygonum punctatum Elliott (Polygonaceae) sobre o ciclo celular de Allium cepa L / Genotoxic and antiproliferative action of Polygonum punctatum Elliott (Polygonaceae) on the cell cycle of Allium cepa L

RESUMO: A espécie Polygonum punctatum Elliott (Polygonaceae) é amplamente utilizada pela população como planta medicinal. O objetivo deste trabalho é o de avaliar o potencial genotóxico e mutagênico de P. punctatum utilizando raízes de bulbos e radículas em sementes germinadas de Allium cepa através do teste in vivo, e realizar comparações da extração do material vegetal por calor (infusões) e extração a frio (extrato). Para isso, foram preparadas dois tipos de soluções, infusões e extratos foliares de P. punctatum, em duas concentrações 0,4 g mL-1 e 2,4 g mL-1. A infusão foi preparada pela adição das folhas secas em água destilada fervente (100ºC), permanecendo por 10 minutos enquanto o extrato foi preparado através da maceração das folhas secas em água destilada fria. Para o teste em A. cepa foram utilizados, para cada tratamento, seis grupos de quatro bulbos e seis caixas gerbox com 50 sementes em cada caixa. Duas lâminas para cada tratamento foram obtidas através da técnica de esmagamento das raízes e coradas com orceína acética 2%. Foram contadas 2000 células por grupo de bulbos e 3000 células por grupo de sementes, observando-se a ocorrência de interrupções em metáfases, alterações cromossômicas estruturais, bem como a inibição ou aumento da divisão celular. Os valores do índice mitótico foram calculados e analisados estatisticamente pelo Teste χ2 (p≤0,05). Os resultados demonstraram que as infusões e os extratos de folhas apresentaram redução nos valores de índices mitóticos nas concentrações utilizadas em relação ao controle em água destilada. Foram identificadas alterações cromossômicas na divisão celular, tais como pontes anafásicas, em todas as concentrações de infusões e extratos indicando assim que P. punctatum possui atividade antiproliferativa e genotóxica.

ABSTRACT: The species Polygonum punctatum Elliott (Polygonaceae) is widely used by the Brazilian population as a medicinal plant. The aims of this study are to evaluate the genotoxic and mutagenic potential of P. punctatum, using its root bulbs and rootlets in germinated seeds of Allium cepa by in vivo testing, and to compare the extraction of plant material by heat (infusions) and cold (extract). Thus, two types of solutions - infusions and leaf extracts - of P. punctatum were prepared at the two concentrations of 0.4 g ml -1 and 2.4 g mL- 1. The infusion was prepared by addition of dry leaves in boiling distilled water (100ºC), remaining for 10 minutes, while the extract was prepared by maceration of dried leaves in cold distilled water. For the A. cepa, we used for each treatment six groups of six bulbs and six seedling boxes with 50 seeds each. Two slides for each treatment were obtained by the technique of crushing the roots, and they were stained with 2 % acetic orcein. For the analysis, 2000 cells per group of bulbs and 3000 cells per group of seeds were counted, and we noted the occurrence of interruptions in the metaphase, chromosomal aberrations, as well as inhibited or increased cell division. The values of the mitotic index were calculated and statistically analyzed by the χ2 test (p ≤ 0.05). The results showed that the infusions and extracts of leaves showed reduced values of mitotic indices in the concentrations used compared to the control in distilled water. Chromosomal alterations were identified in the cell division, in all concentrations of infusions and extracts, thus indicating that P. punctatum has an antiproliferative and genotoxic activity.

The South Australian Breast X-Ray Service: results from a statewide mammographic screening programme.

The South Australian Breast X-Ray Service is a centralised breast cancer screening programme in the State of South Australia. In its first 5 years of operation nearly 100 000 screens were performed. This study reports the clinical performance of the programme and compares it with other published series. Women aged 40 years and over were screened with two-view mammography every 2 years. Radiologists double-read the screening films and multidisciplinary teams assessed the recalled women at a single centre. In the prevalent round 76 106 women were screened, and subsequently 21 506 of them were rescreened. The recall rate for further investigation was 4.9% in the prevalent round and 2.4% in the incident rounds. The cancer detection rate per 1000 women was 7.0 in the prevalent screening round and 3.4 in the incident rounds. Forty-two per cent of invasive carcinomas measured < or = 10 mm in the prevalent screening round and the median tumour size was 12 mm. The benign to malignant biopsy ratio was 1:1.4 in the prevalent round and 1:2.8 in the incident rounds. In the prevalent round 77% of invasive tumours were lymph node negative and this proportion increased to 86% in the incident rounds.

Breast cancer. Incidence, mortality and prospects for control.

Breast cancer is the commonest cancer affecting women in Australia and in most other countries where adequate data are collected. Although mortality rates from breast cancer have changed little in the past 60 years its incidence is increasing and it therefore remains a significant public health problem. This article summarises epidemiological data and prospects for reducing mortality rates from the disease.

Use of peroperative cefoxitin to prevent infection after colonic and rectal surgery.

A double-blind, controlled trial was performed to assess the effect of a short intraoperative course of Cefoxitin, a new broad spectrum cephamycin antibiotic, on the incidence of septic complications following elective colonic and rectal surgery. In addition to a two-day preoperative bowel preparation, patients entered in the study received a short course of either Cefoxitin (three 2g intravenous bolus doses at two-hour intervals, the first before skin incision) or a matching placebo. Thirty-two patients received Cefoxitin and 33 patients received the placebo. Postoperative abdominal wound infections developed in one (3%) of the Cefoxitin-treated patients and nine (27%) of the placebo-treated patients. This difference is statistically significant (p = 0.01). Septic complications remote from the abdominal wound, e.g. intra-abdominal abscesses, occurred in both Cefoxitin-treated and placebo-treated patients, but numbers were too small for meaningful analysis. The study shows that even a very short peroperative course of Cefoxitin is highly effective in reducing postoperative abdominal wound infections after elective colorectal surgery.

Sensitivity of influenza A/New Jersey/8/76 (Hsw1N1) virus to amantadine-HCl.

The appearance of a swine type of influenza A among recruits in Fort Dix, New Jersey, in 1976 prompted an evaluation of the sensitivity of this virus to amantadine - HCl. Well-tolerated levels of the drug effectively blocked replication of the influenza A/New Jersey/8/76 (Hsw1N1) virus isolate in three laboratory models: monkey kidney cells, embryonated eggs, and intranasally infected mice. On a comparative basis this virus would appear to be more sensitive to amantadine - HCl than human influenza A strains, including the recent Victoria (1975) strain. All strains of influenza A virus continue to be sensitive to amantadine - HCl.