Estudo citofotométrico da expressão dos marcadores tumorais Caspase-3 e Ki-67 no adenocarcinoma gástrico Cytophotometric study of the expression of tumoral markers Caspase-3 and Ki-67 in gastric adenocarcinoma

RACIONAL: A carcinogênese gástrica é processo complexo e depende de fatores genéticos, ambientais e infecciosos. Nos últimos anos, houve grandes avanços nos campos da genética e da biologia molecular, sobre o desenvolvimento dos tumores. Os marcadores tumorais são substâncias ausentes nos tecidos normais e que podem ser identificadas em tecidos com câncer. Através de procedimentos imunoistoquímicos eles podem ser estudados. OBJETIVOS: Descrever a expressão citofotométrica do marcador tumoral Ki-67 analisando a densidade óptica e o índice de marcagem no adenocarcinoma de estômago. Descrever a expressão citofotométrica do marcador tumoral Caspase-3 analisando a densidade óptica e o índice de marcagem no adenocarcinoma de estômago. Comparar o índice de marcagem e densidade óptica dos marcadores tumorais Ki-67 e Caspase-3 no adenocarcinoma de estômago. MÉTODO: Foram selecionados, inicialmente, 58 blocos com espécime de adenocarcinoma gástrico coletados nos Serviços de Anátomo-Patologia do Hospital do Gama - Brasília (DF) e Hospital Dom Orione - Araguaina (TO), e analizados no Laboratório de Citologia e Histopalogia Ltda - CITOLAB, Curitiba (PR). Foram aproveitados 31 blocos para o estudo histológico e imunoistoquímico realizado pelo sistema de análise computarizado SAMBA 4000. RESULTADOS: Das 31 lâminas estudas, 15 (48%) foram marcadas pelo marcador Ki-67, 22 (71%) foram marcadas pelo marcador Caspase-3 e 14 (45%) marcaram com os dois marcadores. CONCLUSÕES: A expressão citofométrica do marcador Ki-67 foi observada em 15 lâminas da amostra estudada e apresentaram média do índice de marcagem de 36,85%, enquanto a densidade óptica apresentou média de 29,33 pixels. A expressão citofotométrica do marcador Caspase-3 foi observada em 22 lâminas da amostra estudada e apresentaram média do índice de marcagem de 87,71% e 60,74 pixels de média para a densidade óptica. Na comparação do índice de marcagem dos marcadores Ki-67 e Caspase-3 com a leitura de 14 lâminas, observamos que existe diferença significativa (P<0,001) em favor do marcador Caspase-3, o mesmo aconteceu para a densidade óptica também com diferença significativa (P<0,001).<br>BACKGROUND: Gastric tumorigenesis is a complex mechanism where genetic, enviromental and infeccious interferences may occur. In the last few years, advances in molecular biology brought a new way in the research of the malignancies using tumoral markers and imunohistochemistry. AIM: To describe the cytophotometric expression of tumoral markers Ki-67 and caspase-3, analyzing optical density and labeling index as parameters in gastric adenocarcinoma. To compare the labeling index and optical density of Ki-67 and Caspase-3 in gastric adenocarcinoma. METHODS: Fifty eight paraffin blocks containing gastric adenocarcinomas specimens were collected in the Serviços de Anátomo-Patologia do Hospital do Gama - Brasília (DF) and Hospital Dom Orione - Araguaina (TO), being analyzed at CITOLAB - Cytology and Hystopathology Laboratory Ltda, in Curitiba (PR). A total of 31 of the blocks were used for hystological studies. Immunohistochemistry was performed utilizing the SAMBA 4000 computerized analysis system. RESULTS: Of the 31 slides studies, 15 (48%) were marked by Ki-67, 22 (71%) were marked by Caspase-3 and 14 (45%) were marked by both of the tumoral markers. CONCLUSIONS: Cytophotometric expression of Ki-67 was observed in 15 of the slides studied, presenting an average labeling index of 36,85%, where as the optical density showed an average of 29,33 pixels. Cytophotometric expression of Caspase-3 was observed in a total of 22 slides, presenting an average labeling index of 87,71% and optical density of 60,74 pixels. When comparing the labeling indexes of both of the tumoral markers Ki-67 and Caspase-3 concerning the 14 slides analyzed, a significant difference (P<0,001

Intravenous zoledronic acid in postmenopausal women with low bone mineral density.

BACKGROUND: Bisphosphonates are effective agents for the management of osteoporosis. Their low bioavailability and low potency necessitate frequent administration on an empty stomach, which may reduce compliance. Gastrointestinal intolerance limits maximal dosing. Although intermittent intravenous treatments have been used, the optimal doses and dosing interval have not been systematically explored. METHODS: We studied the effects of five regimens of zoledronic acid, the most potent bisphosphonate, on bone turnover and density in 351 postmenopausal women with low bone mineral density in a one-year, randomized, double-blind, placebo-controlled trial. Women received placebo or intravenous zoledronic acid in doses of 0.25 mg, 0.5 mg, or 1 mg at three-month intervals. In addition, one group received a total annual dose of 4 mg as a single dose, and another received two doses of 2 mg each, six months apart. Lumbar-spine bone mineral density was the primary end point. RESULTS: There were similar increases in bone mineral density in all the zoledronic acid groups to values for the spine that were 4.3 to 5.1 percent higher than those in the placebo group (P<0.001) and values for the femoral neck that were 3.1 to 3.5 percent higher than those in the placebo group (P<0.001). Biochemical markers of bone resorption were significantly suppressed throughout the study in all zoledronic acid groups. Myalgia and pyrexia occurred more commonly in the zoledronic acid groups, but treatment-related dropout rates were similar to that in the placebo group. CONCLUSIONS: Zoledronic acid infusions given at intervals of up to one year produce effects on bone turnover and bone density as great as those achieved with daily oral dosing with bisphosphonates with proven efficacy against fractures, suggesting that an annual infusion of zoledronic acid might be an effective treatment for postmenopausal osteoporosi

Effects of endurance training on the breathing pattern of professional cyclists

The aim of this longitudinal study was to clarify the changes induced by endurance training on the breathing pattern of 13 professional cyclists (age±SD: 24±2 years; V̇O2 max ∼75 ml · kg-1 · min-1) during the three periods (rest, precompetition, and competition) of a sports season. Both the volume and the intensity of training were quantified during these periods. In each session (corresponding to each of the three periods) all subjects performed (1) a pulmonary function test (to measure forced vital capacity [FVC], peak expiratory flow [PEF], and maximal voluntary ventilation [MVV]), and (2) a ramp test until exhaustion on a cycle ergometer (workload increases of 25 W · min-1). The following variables were recorded every 100 W until the end of the tests: pulmonary ventilation (V̇E, in / · min-1 BTPS), tidal volume (VT, in IBTPS), breathing frequency (fb, in breaths · min-1), ventilatory equivalents for oxygen (V̇E · V̇O2 -1) and carbon dioxide (V̇E · V̇CO2 -1), inspiratory (TI) and expiratory (TE) times (s), ratio of TI to total respiratory duration or inspiratory "duty cycle" (TI/TTOT), and mean inspiratory flow rate (VT/TI, in /· s-1). The results showed no changes in any of these variables (p>0.05) between the three periods of study, despite significant changes in training loads (i.e., increases in the volume and/or intensity of training throughout the season). These findings suggest that endurance conditioning does not alter the breathing pattern of professional cyclists during an incremental exercise test.Sin financiación1.077 JCR (2001) Q3, 54/74 PhysiologyUE