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91.
C. elegans egg-laying behavior is affected by environmental cues such as osmolarity1 and vibration2. In the total absence of food C. elegans also cease egg-laying and retain fertilized eggs in their uterus3. However, the effect of different sources of food, especially pathogenic bacteria and particularly Enterococcus faecalis, on egg-laying behavior is not well characterized. The egg-in-worm (EIW) assay is a useful tool to quantify the effects of different types of bacteria, in this case E. faecalis, on egg- laying behavior.EIW assays involve counting the number of eggs retained in the uterus of C. elegans4. The EIW assay involves bleaching staged, gravid adult C. elegans to remove the cuticle and separate the retained eggs from the animal. Prior to bleaching, worms are exposed to bacteria (or any type of environmental cue) for a fixed period of time. After bleaching, one is very easily able to count the number of eggs retained inside the uterus of the worms. In this assay, a quantifiable increase in egg retention after E. faecalis exposure can be easily measured. The EIW assay is a behavioral assay that may be used to screen for potentially pathogenic bacteria or the presence of environmental toxins. In addition, the EIW assay may be a tool to screen for drugs that affect neurotransmitter signaling since egg-laying behavior is modulated by neurotransmitters such as serotonin and acetylcholine5-9. 相似文献
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Dr. Rosemarie Diemer 《Planta》1961,57(2):111-137
Ohne ZusammenfassungMit 17 Textabbildungen 相似文献
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Clinical behaviour of prostatic specific antigen and prostatic acid phosphatase: a comparative study
J Morote Robles A Ruibal Morell J A De Torres Mateos A Soler Roselló 《The International journal of biological markers》1989,4(2):87-94
We assayed prostatic specific antigen (PSA) and prostatic acid phosphatase (PAP) serum levels in 1383 patients using a double antibody radioimmunoassay (RIA) I125. Establishing the upper normal limit in 10 ng/ml PSA and 2.5 ng/ml for PAP, the false positive results were only 1.9 and 5.1 percent in men with non-prostatic benign or malignant pathology and respectively 0 and 2.2 percent in women. We detected false positive levels for these two tumoral markers in 3.5 and 4.7 percent of patients with non-complicated benign prostatic hypertrophy, 64.8 and 19.2 percent in complicated benign prostatic hypertrophy, 24 and 16 percent in acute prostatitis and 3.3 percent in chronic prostatitis. The sensitivity in patients with prostate cancer was 87.2 percent for PSA and 64.1 percent for PAP, and there was a better correlation with PSA than PAP for tumoral spread and histological grading. Finally, clinical efficacy was higher with PSA and was no better when both markers were assayed. 相似文献
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Methicillin-resistant Staphylococcus aureus (MRSA) is a major cause of preventable nosocomial infections and is endemic in hospitals worldwide. The effectiveness of infection control policies varies significantly across hospital settings. The impact of the hospital context towards the rate of nosocomial MRSA infections and the success of infection control is understudied. We conducted a modelling study to evaluate several infection control policies in surgical, intensive care, and medical ward specialties, each with distinct ward conditions and policies, of a tertiary public hospital in Sydney, Australia. We reconfirm hand hygiene as the most successful policy and find it to be necessary for the success of other policies. Active screening for MRSA, patient isolation in single-bed rooms, and additional staffing were found to be less effective. Across these ward specialties, MRSA transmission risk varied by 13% and reductions in the prevalence and nosocomial incidence rate of MRSA due to infection control policies varied by up to 45%. Different levels of infection control were required to reduce and control nosocomial MRSA infections for each ward specialty. Infection control policies and policy targets should be specific for the ward and context of the hospital. The model we developed is generic and can be calibrated to represent different ward settings and pathogens transmitted between patients indirectly through health care workers. This can aid the timely and cost effective design of synergistic and context specific infection control policies. 相似文献
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AbstractSmall game seems to have increased during the Upper Palaeolithic to the detriment of large game on the Iberian Peninsula. The economical and socio-cultural factors associated with this ecological shift represent a widely discussed topic. The present work attempts to elucidate the subsistence strategies occurring through the Late Pleistocene in Iberia using the example of the Molí del Salt (Tarragona, Spain), an archaeological site located in the NE of the Iberian Peninsula. The taphonomical analysis of faunal remains shows a high incidence of human activity on different taxonomical groups, although the European rabbit (Oryctolagus cuniculus) stands out. This taxon presents cut-marks related to various processing activities (e.g. skinning and defleshing) and intentional bone breakage to access marrow. The abundance of specimens with human-induced damage enables us to make inferences regarding the procurement strategies and the occupational patterns at the site, where long and stable occupations seem to have occurred. 相似文献
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