Intake of vitamin D and risk of breast cancer--a meta-analysis

Vitamin D insufficiency has been shown to be associated with a number of conditions including diabetes, multiple sclerosis and the overall risk of cancer. We aimed at studying the association between vitamin D intake and risk of breast cancer in a meta-analysis. We searched Pubmed, Embase, and Web of Science using the MESH terms "vitamin D" and "breast cancer". A total of 1731 studies were identified, but only 6 studies contained original data on the association between intake of vitamin D and risk of breast cancer. Overall there was no association between amount of vitamin D and risk of breast cancer (RR=0.98, 95% CI: 0.93-1.03, test for heterogeneity p<0.01). However, most studies reported on very low intakes of vitamin D (typically in the range 100-400IU/day). Restricting the analyses to intakes >/=400IU/day yielded a more homogenous result with a trend towards less breast cancer with >/=400IU/day vs. the lowest intake (typically <50-150IU/day), RR=0.92, 95% CI: 0.87-0.97, p for heterogeneity 0.14. In conclusion there may be a trend towards fewer cases of breast cancer with higher intakes of vitamin D (>/=400IU/day). However, more research is needed, preferably in the form of randomized-controlled trials.     

Comparison of Worm Control Strategies in Grazing Sheep in Denmark

Control of nematode parasites with reduced reliance on the use of anthelmintics was studied in 16 ewes with suckling twin lambs on contaminated pasture in Denmark. Ewes and lambs were treated with albendazole at turn-out 3 May. Ewes were removed from the groups on 26 July, and lambs were slaughtered on 11 October. The animals were allocated to 4 groups of 8 lambs and their 4 ewes. Group TS was treated with albendazole at weeks 3, 6 and 8 after turnout and set-stocked; group TM was similarly treated but moved to clean pasture in conjunction with the last drenching; group US was untreated and set-stocked, and group UM was left untreated but moved to clean pasture week 8 after turn-out. Supplementary feed was offered in June and August due to scarcity of pasture. Strategic treatments of ewes and lambs weeks 3, 6 and 8 after turn-out, with or without a move to clean pasture, were highly effective in controlling nematode infections for most of the season. This was reflected in better weight gains and carcass characteristics in the treated compared to untreated lambs, resulting in an average increase in the value of the product by 36%. The effect of moving without treatment (UM) on faecal egg counts was limited but peak pasture infectivity was reduced to less than 10% compared to the set-stocked group and weight gains of lambs were significantly better despite poor feed availability in late season. The study showed that under set-stocked conditions repeated anthelmintic treatments of both ewes and lambs in early season may ensure sufficient nematode control whereas moving animals to clean pasture without dosing was less efficient. The latter may, however, still be a viable option in organic and other production systems where routine use of anthelmintics is banned, particularly if weaning and moving are combined or a second move is performed.     

Investigation of apoptosis in cultured cells infected with equine herpesvirus 1

Many viruses alter different stages of apoptosis of infected cells as a strategy for successful infection. Few studies have addressed mechanisms of equine herpesvirus 1 (EHV-1) strain-induced cell death. We investigated the effect of an abortigenic strain (AR8 strain) on heterologous Madin–Darby bovine kidney cells and homologous equine dermis (ED) cells cell lines. We compared morphologic and biochemical features of early and late apoptosis at different postinfection times. We investigated translocation of phosphatidylserine to the cell surface, nuclear fragmentation and changes in the cytoskeleton using flow cytometry and annexin V/propidium iodide staining, DNA laddering, terminal deoxynucleotidyl transferase UTP nick-end labeling assay and immunofluorescence staining of cytokeratin 18 cleavage. AR8 EVH-1 strain interfered with apoptosis in both cell lines, particularly during the middle stage of the replication cycle; this was more evident in ED cells. Although this antiapoptotic effect has been reported for other alpha herpesviruses, our findings may help elucidate how EHV-1 improves its infectivity during its cycle.     

在中国应用垂直波束雷达监测褐飞虱和其他水稻害虫迁飞的可行性

近年来,可用于昆虫迁飞研究且可自动运行的垂直波束雷达(vertical-looking radar,VLR)的发展使得对迁飞性害虫的周年长期自动监测成为可能。本文提供了我们对能否将这种雷达应用于中国的褐飞虱和其他水稻害虫的监测与预测体系以改善其综合治理的可行性研究结果。以往的研究已经表明,这些害虫一般在300—2000m高度迁飞;而我们根据褐飞虱的雷达和射有效截面的计算结果表明,目前使用的3．2cm波长的VLR对褐飞虱个体目标的最大可检测高度仅约240m;虽然建造一部8．8mm波长的VLR即可覆盖褐飞虱迁飞高度的绝大部分,但其造价和维护费用均过于昂贵。为此,一个更可行的解决方案是,以3．2cm波长的VLR作为包括大多数水稻害虫在内的个体较大的迁飞性害虫的监测工具。     

Risk taking in relation to reproductive investments and future reproductive opportunities: field experiments on nest-guarding common gobies, Pomatoschistus microps

The common goby, Pomatoschistus microps, has parental care,with males building nests and guarding the fertilized eggs untilhatching. We carried out field experiments to estimate the responseof males to predation risk in relation to developmental stageof their brood and time of the season. Artificial nest substrateswere placed in a shallow bay with soft substrate. After thenest had been built and eggs laid in it, a glass jar containinga potential predator (an eelpout, Zoarces viviparus) was placed15 cm from the goby's nest. We subsequently chased the malegoby away from the nest and measured his flight distance andtime until return. This was repeated once a day in May, June,and August. Time away from the nest decreased in the courseof one brood cycle, with a steeper slope in May compared tothe other months, as a result of longer times away from thenest in the beginning of the experiment. Flight distance decreasedslightly over one brood cycle and was longer in June than inMay and August. In another experiment, a male P. microps waspresented to the nest-guarding male, simulating a potentialcompetitor for the nest. Again, we found a decrease in returntime with advancement of the brood cycle, but the fish returnedfaster than when facing a predator, especially in the beginningof the brood cycle. No effect of habituation to the treatmentwas found, but there seemed to be a slight influence of developmentstage of the eggs. Thus, risk taking by nest-guarding male P.microps appears to be influenced by time already spent guardingone particular brood and the prospect for future reproductiveopportunities. [Behav Ecol 1991 ;2:351–359]     

Temporal development of vegetation and geomorphology in a man-made beach-dune system by natural processes

Twenty-four yrs of primary succession in a man-made beach-dune system at the Baltic coast of Denmark, built of calcareous, marine sand and the dune planted with Ammophila arenaria , was studied by qualitative observations, quantitative records in permanent plots, levelling and soil analysis within a selected area of 0.75 ha. The aim of the study was to discuss whether human initiated and influenced beach and dune dynamics mimick natural beach and dune processes, and to discuss the relationship between succession and zonation. During the study period, which started in 1979, the man-made dune stabilized rather fast. In the stabilized dune, a sand-pararendzina with a thin A-horizon developed. The beach expanded by accretion of less calcareous, marine sand. On the beach new dunes, 3 m high, successively developed. The number of species in the study area increased from 16 to 55, accompanied by species and life form dynamics, characteristic for primary succession on sandy coasts. A gradual change in species composition of the permanent plots, which appeared by a DCA analysis, could by using TWINSPAN be structured into four groups or plant communities, which reflect succession as well as zonation. Two groups represent the vegetation of sandy beaches with annual dicotyledon species, and mobile dunes dominated by rhizomatous geophytes, especially A. arenaria. The two other groups represent stabilized, calcareous dune, dominated by hemicryptophytes, specially Festuca rubra , and less stabilized dune with F. rubra and the invasive alien Rosa rugosa. It was concluded, that the main trends in the geomorphological and vegetational development of the man-made beach-dune system is similar to the development in natural dunes. In the future, further accretion and seaward dune formation may be expected, but is it also expected, that larger parts of the area gradually will be covered by low scrubs of R. rugosa.     

Functional changes in human leukemic cell line HL-60. A model for myeloid differentiation

Polar solvents induce terminal differentiation in the human promyelocytic leukemia cell line HL-60. The present studies describe the functional changes that accompany the morphologic progression from promyelocytes to bands and poly-morphonuclear leukocytes (PMN) over 9 d of culture in 1.3 percent dimethylsulfoxide (DMSO). As the HL-60 cells mature, the rate of O(2-) production increase 18-fold, with a progressive shortening of the lag time required for activation. Hexosemonophosphate shunt activity rises concomitantly. Ingestin of paraffin oil droplets opsonized with complement or Ig increases 10-fold over 9 d in DMSO. Latex ingestion per cell by each morphologic type does not change significantly, but total latex ingestion by groups of cells increases with the rise in the proportion of mature cells with greater ingestion capacities. Degranulation, as measured by release of β-glucuronidase, lysozyme, and peroxidase, reaches maximum after 3-6 d in DMSO, then declines. HL-60 cells contain no detectable lactoferrin, suggesting that their secondary granules are absent or defective. However, they kill staphylococci by day 6 in DMSO. Morphologically immature cells (days 1-3 in DMSO) are capable of O(2-) generation, hexosemonophosphate shunt activity, ingestion, degranulation, and bacterial killing. Maximal performance of each function by cells incubated in DMSO for longer periods of time is 50-100 percent that of normal PMN. DMSO- induced differentiation of HL-60 cells is a promising model for myeloid development.     

Polypeptide analysis of individual immunoprecipitates from crossed immunoelectrophoresis

The method presented makes it possible to analyze the polypeptides of the antigen of individual immunoprecipitates. Crossed immunoelectrophoresis of radioactively labeled human serum proteins, herpes simplex virus type 1 antigens, and human erythrocyte membrane proteins was performed using polyspecific antibody preparations. Individual immunoprecipitates were cut out of the agarose gel and the polypeptides were eluted with sodium dodecyl sulfate and 2-mercaptoethanol. The polypeptide composition and corresponding molecular weight of the antigenic material were determined by SDS-polyacrylamide-gel electrophoresis followed by autoradiography.