三氧化二砷对食管癌细胞增殖和热休克蛋白70表达的影响

目的：研究三氧化二砷（As2O3）对食管癌细胞增殖和热休克蛋白70（HSP70）表达的影响。方法：通过相差显微镜、流式细胞术、免疫细胞化学染色和免疫印迹分析等方法观察As2O3对人食管癌细胞株EC1的作用效果和作用机制。结果：与对照组相比,经2μmol/L和5μmol/Las2O3作用的细胞出现明显的生长抑制,G2/M期细胞比例增加;2μmol/Las2O3作用48h后经Ecl细胞HSP70（heat shock protein70）及HSC70(heat shock cognate protein70)表达均增加。结论：As2O3诱导食管癌细胞G2/M期阻滞抑制细胞增殖和生长;HSP70的升高是细胞对As2O3作用后出现的应激反应,并与细胞周期阻滞相关。     

Can general practitioners influence exercise habits? Controlled trial.

A health promotion campaign in the community organised by the general practitioner was evaluated by the use of a questionnaire before and after the campaign, both in the village where the campaign was based and in a control village. There was a general increase in the amount of exercise that people in both villages took. The results showed that having received a questionnaire, and been subject to the campaign, more people took exercise regularly.     

Breaking dormancy during flood and drought: sublethal growth and physiological responses of three emergent wetland herbs used in bioretention basins

Bioretention basins are man-made topographic depressions designed to collect and retain surface water runoff. In most cases these basins are used to prevent flooding and/or remove environmentally harmful pollutants and sediments from entering natural aquatic systems. To maximize environmental benefits, these systems are often planted with flood-tolerant wetland hydrophytes that are capable of withstanding extended periods of drought. Unfortunately, little is known about how these plants respond to extreme hydrologies while breaking seasonal dormancy. The purpose of this study was to better understand the morphological and physiological responses of three wetland species (Pontederia cordata L., Saururus cernuus L., and Schoenoplectus tabernaemontani C.C. Gmel. Palla) often used in bioretention basins while emerging from dormancy in either flooded or drought conditions. Results indicate that only S. tabernaemontani was affected morphologically by drought with lower leaf area and aboveground biomass. While significant reductions in stomatal surface indices were also observed in drought-treated S. tabernaemontani, all three species had reductions in stomatal conductance (g) when grown in drier soils. Moreover, drought conditions promoted decreases in leaf water potential (Ψ _leaf) for all three species, and reductions in tissue water content (θ) for P. cordata and S. tabernaemontani. Based on the overall morphological and physiological responses, S. cernuus maintained the lowest productivity, and appeared to be the best suited for tolerating sustained soil water deficits. If high plant productivity is desired, however, S. tabernaemontani was able to maintain high plant growth while making necessary modifications that facilitated greater drought-resistance.     

Increased amounts of hybrid (heavy/heavy) DNA in Bloom's syndrome fibroblasts

The nuclear DNA of fibroblasts from patients suffering with Bloom's syndrome, density labeled for less than one round of DNA replication to give heavy/light molecules, was examined for spontaneous amounts of heavy/heavy DNA (hybrid DNA). When compared to normal fibroblasts the Bloom's syndrome cells exhibited a sixfold increase in such DNA.     

Contemporary habitat discontinuity and historic glacial ice drive genetic divergence in Chilean kelp

Background  

South America's western coastline, extending in a near-straight line across some 35 latitudinal degrees, presents an elegant setting for assessing both contemporary and historic influences on cladogenesis in the marine environment. Southern bull-kelp (Durvillaea antarctica) has a broad distribution along much of the Chilean coast. This species represents an ideal model taxon for studies of coastal marine connectivity and of palaeoclimatic effects, as it grows only on exposed rocky coasts and is absent from beaches and ice-affected shores. We expected that, along the central Chilean coast, D. antarctica would show considerable phylogeographic structure as a consequence of the isolating effects of distance and habitat discontinuities. In contrast, we hypothesised that further south - throughout the region affected by the Patagonian Ice Sheet at the Last Glacial Maximum (LGM) - D. antarctica would show relatively little genetic structure, reflecting postglacial recolonisation.     

Headache and Blood Pressure in the Community

Following a survey of headaches, in which questionnaires were sent to a random sample of the general population, groups of individuals with headache, unilateral headache, or migraine, and a fourth group who had not had a headache in the previous year were examined. Measurements of arterial blood pressure on 414 individuals gave no evidence of any differences between these groups for either systolic or diastolic pressure. The number of individuals that could be regarded as hypertensive in this community-based study was small, but it is concluded that most individuals with headache, and with migraine, have blood pressures similar to those who do not have headaches.     

Exploring mechanisms of sex differences in longevity: lifetime ovary exposure and exceptional longevity in dogs

To move closer to understanding the mechanistic underpinnings of sex differences in human longevity, we studied pet dogs to determine whether lifetime duration of ovary exposure was associated with exceptional longevity. This hypothesis was tested by collecting and analyzing lifetime medical histories, age at death, and cause of death for a cohort of canine ‘centenarians’– exceptionally long‐lived Rottweiler dogs that lived more than 30% longer than average life expectancy for the breed. Sex and lifetime ovary exposure in the oldest‐old Rottweilers (age at death, ≥ 13 years) were compared to a cohort of Rottweilers that had usual longevity (age at death, 8.0–10.8 years). Like women, female dogs were more likely than males to achieve exceptional longevity (OR, 95% CI = 2.0, 1.2–3.3; P = 0.006). However, removal of ovaries during the first 4 years of life erased the female survival advantage. In females, a strong positive association between ovaries and longevity persisted in multivariate analysis that considered other factors, such as height, body weight, and mother with exceptional longevity. A beneficial effect of ovaries on longevity in females could not be attributed to resistance against a particular disease or major cause of death. Our results document in dogs a female sex advantage for achieving exceptional longevity and show that lifetime ovary exposure, a factor not previously evaluated in women, is associated with exceptional longevity. This work introduces a conceptual framework for designing additional studies in pet dogs to define the ovary‐sensitive biological processes that promote healthy human longevity.