Significance of exercise and bed rest in pregnancy--study on the lying postures of gravidas during sleep (2)

For the purpose of determining the most reasonable lying posture for pregnant women, we investigated the lying positions of both 247 non-pregnant women and 302 pregnant women during sleep. As for the rate of each position during the entire period of observation, 33.2% of the non-pregnant women were in the supine position, 41.2% in the lateral position, 18.4% in Sims' position and 7.1% in the prone position. In the pregnant group, the rate of supine position, simple lateral position and Sims' position was 34.2%, 52.2% and 12.7%, respectively, but the rate of the prone position was limited to 0.8%. All of the gravidas assuming the prone position were at less than 16 weeks of gestation. Non-pregnant women could sleep in a variety of positions, but pregnant women could assume the prone position during sleep only in the stage when the abdomen is not yet prominent or distended. Pregnant women were restricted significantly, either consciously or unconsciously, with progress in gestation.     

Comparison of the physiology, morphology, and leaf demography of tropical saplings with different crown shapes

Branch architecture, leaf photosynthetic traits, and leaf demography were investigated in saplings of two woody species, Homolanthus caloneurus and Macaranga rostulata, co-occurring in the understory of a tropical mountain forest. M. rostulata saplings have cylindrical crowns, whereas H. caloneurus saplings have flat crowns. Saplings of the two species were found not to differ in area-based photosynthetic traits and in average light conditions in the understory of the studied site, but they do differ in internode length, leaf emergence rate, leaf lifespan, and total leaf area. Displayed leaf area of H. caloneurus saplings, which have the more rapid leaf emergence, was smaller than that of M. rostulata saplings, which have a longer leaf lifespan and larger total leaf area, although M. rostulata saplings showed a higher degree of leaf overlap. Short leaf lifespan and consequent small total leaf area would be linked to leaf overlap avoidance in the densely packed flat H. caloneurus crown. In contrast, M. rostulata saplings maintained a large total leaf area by producing leaves with a long leaf lifespan. In these understory saplings with a different crown architecture, we observed two contrasting adaptation strategies to shade which are achieved by adjusting a suite of morphological and leaf demographic characters. Each understory species has a suite of morphological traits and leaf demography specific to its architecture, thus attaining leaf overlap avoidance or large total leaf area.     

Protective action of indole‐3‐acetic acid on induced hepatocarcinoma in mice

In this study, we report the protective effects of IAA on diethylnitrosamine (DEN)‐induced hepatocarcinogenesis. BALB/c mice received daily IAA at 50 (T₅₀), 250 (T₂₅₀), and 500 (T₅₀₀) mg Kg^?1 per body mass by gavage for 15 days. At day 15, animals were administered DEN and sacrificed 4 h later. Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were analyzed in sera. In addition, hepatomorphologic alterations, activity of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and glutathione reductase (GR), gene expression of antioxidant enzymes and DNA integrity were evaluated in the liver. IAA administration did not show any alterations in any of the parameters available, except for a reduction of the gene expression for antioxidant enzymes by 55, 56, 27, and 28% for SOD, CAT, GPx, and GR upon T₅₀₀, respectively compared with the control. Several hepatic alterations were observed by DEN exposure. Moreover, IAA administration at 3 doses was shown to provide a total prevention of the active reduction of CAT and GR induced by DEN exposure compared with the control. IAA at T₅₀₀ was shown to give partial protection (87, 71, 57, and 90% for respectively SOD, CAT, GPx, and GR) on the down‐regulation of the enzymes induced by DEN and this auxin showed a partial protection (50%) on DEN‐induced DNA fragmentation for both parameters when compared to DEN alone. This work showed IAA hepatocarcinogenesis protection for the first time by means of a DEN‐protective effect on CAT and GR activity, and by affecting antioxidant gene expression and DNA fragmentation. Copyright © 2008 John Wiley & Sons, Ltd.     

Altered expression of connexins in urethane-induced mouse lung adenomas

Lung carcinogenesis is a multistep process whose molecular alterations can be studied in mouse models. Urethane, a specific lung tumor carcinogen, can induce adenomas in mice. Mouse lung alveolar cells reportedly generate lung neoplasms, and express connexins 26, 32, 43 and 46. The aim of the present study was to evaluate the expression of connexins in urethane-induced lung adenomas. Fifteen-day-old CD1 male mice received 2 i.p. injections of urethane (1.5 g/kg bw). The mice were euthanized 25 weeks after urethane injection, and lung adenomas were quantified. Lung tissue and lung adenomas were harvested and the RNA was extracted. The expression of connexins 26, 32, 43 and 46 was evaluated by Real-Time PCR, and these proteins were identified by Western blot. Immunohistochemistry revealed the distribution pattern of these connexins in lung tissue and adenomas. The treatment with urethane was associated with the downregulation of Cx26, 32 and 46 expressions, and with the upregulation of Cx43 expression in lung tissue. Surprisingly, in lung adenomas Cx32 and Cx43 expressions were not detected, although the expression of connexins 26 and 46 was present. Western blot and immunohistochemistry corroborated the RT-PCR data. These results may indicate a role of Cx32 and Cx43 in urethane-induced lung carcinogenesis, since their absence may contribute to the development of urethane induced lung tumors. The role of Cx26 and Cx46 is yet to be determined.     

Prune homolog 2 with BCH domain (PRUNE2) gene expression is associated with feed efficiency-related traits in Nelore steers

Mammalian Genome - Animal feeding is a critical factor in increasing producer profitability. Improving feed efficiency can help reduce feeding costs and reduce the environmental impact of beef...     

Deletion of a single allele of Cx43 is associated with a reduction in the gap junctional intercellular communication and increased cell proliferation of mouse lung pneumocytes type II

OBJECTIVES: Connexins (Cx) are proteins that form the gap junctional channels at neighbouring plasma membranes between adjacent cells. Cxs are involved in cell communication, which is reportedly correlated with cell proliferation and differentiation. Alterations in connexin expression and/or gap junctional intercellular communication (GJIC) capacity have long been postulated to be important in a number of pathological conditions including cancer. This study was performed to determine the consequences of the deletion of a single allele of Gja1 (Cx43 gene) in Alveolar Type II cells (APTIIs), and its impact on GJIC and cell proliferation. MATERIAL AND METHODS: In order to do so, APTIIs from wild type (Cx43(+/+)) and heterozygous (Cx43(+/-)) mice were harvested and cultured for 4 days. The GJIC capacity was evaluated by scrape-loading method, with the transfer of lucifer yellow dye. The expression of Cx43 was evaluated by immunofluorescence method and Western blotting. Cell proliferation was evaluated by 3-(4,5-dimethylthazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Results: It was observed that GJIC capacity was significantly reduced and cell proliferation index was significantly higher in Cx43(+/-) cells compared to Cx43(+/+) cells. CONCLUSIONS: These results show that knocking out one allele of Cx43 leads to a lower cell to cell communication capacity, and consequently induces a higher cell proliferation. Because chemically induced lung adenomas in mice are known to originate from APTIIs, these alterations may play a critical role in their susceptibility to lung carcinogenesis.     

Effects of far-infrared radiation on lactation

Massage and warm compresses to the breast have been commonly used for stimulating and/or increasing blood flow to the breasts, and for enhancing lactation consequently. However, more effective and easier remedies seem to be necessary. The vasodilating and warming effects of ceramics far-infrared radiation were studied. Based on the results obtained, the effect of a ceramic disc on lactation, attached to the breast skin, was evaluated in 27 puerperal women who had had poor lactation previously and in 36 with currently poor lactation monthly until weaning. Approximately 3/4 of these puerperal women enhanced lactation significantly one month after attachment and 1/2 of the women were able to breast-feed until weaning. Thus, we found that ceramics far-infrared radiation may be an effective remedy for enhancing lactation.     

Histological alterations in the livers of Cx43-deficient mice submitted to a cholestasis model

Gap junction intercellular communication capacity and connexin expression are reportedly involved in cell proliferation. To understand the participation of connexins in biliary duct hyperplasia, a cholestasis model was applied to mice with heterologous deletion of Gja 1, the connexin 43 (Cx43) gene. Heterozygous (Cx43+/-) knockout (KO) and wild-type mice (Cx43+/+) (WT) were submitted to bile duct ligation and euthanized at different time points (48 h, 7 days, and 14 days) after surgery. After euthanasia, the macroscopic and microscopic liver alterations were examined. A histomorphometric study of the livers was performed. For this purpose, a grid containing 100 points was applied to each liver section. The volumetric fraction of bile ducts, hepatocytes, arterioles, and terminal hepatic vein were quantified. Cell proliferation was also quantified by western blot PCNA. High mortality was observed in both genotypes. The heterologous deletion of Cx43 did not affect the biliary duct hyperplasia or most of the other parameters analyzed; however, the Cx43-deficient mice showed decrease in hepatic vein angiogenesis in comparison with the wild-type mice 48 h after surgery. In conclusion, our results indicate that the Cx43 gene heterologous deletion does not affect the biliary duct hyperplasia; on the other hand, connexin 43 deficiencies do affect the hepatic vein angiogenesis, although other studies to understand the details of this influence will be necessary.