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Séverine Tasker Iain R. Peters Michael J. Day Barbara Willi Regina Hofmann-Lehmann Timothy J. Gruffydd-Jones Chris R. Helps 《Microbial pathogenesis》2009
The aim of the study was to describe blood and tissue copy number distribution during Mycoplasma haemofelis infection and determine if sequestration of organisms in body tissues could explain blood copy number cycling in infected cats. Thirteen domestic–shorthaired cats were used. Blood samples were regularly collected, and at a differing time point post-infection for each cat, tissue samples also collected, for quantitative PCR (qPCR). Absolute haemoplasma copy numbers were calculated for all blood and tissue samples, as well as an estimation of the ratio of tissue haemoplasma copy number to that expected in the tissue if a positive qPCR result arose due to tissue blood supply alone. Cats with high or moderate M. haemofelis blood copy numbers at the time of tissue collection had fewer M. haemofelis copies in most tissues than expected due to the tissue blood supply alone; only splenic and lung tissues consistently contained more M. haemofelis. However tissues collected from cats at a time of very low M. haemofelis blood copy numbers, when putative copy number cycling nadirs were occurring, were usually qPCR negative. Hence no evidence of significant tissue M. haemofelis sequestration was found in this study to explain the copy number cycling reported with this feline haemoplasma species. 相似文献
84.
Daniela Dreymueller PhD Bernd Denecke PhD Willi Jahnen‐Dechent PhD 《Wound repair and regeneration》2013,21(1):44-54
In adults, repair of deeply injured skin wounds results in the formation of scar tissue, whereas in embryos wounds heal almost scar‐free. Macrophages are important mediators of wound healing and secrete cytokines and tissue remodeling enzymes. In contrast to host defense mediated by inflammatory M1 macrophages, wound healing and tissue repair involve regulatory M2/M2‐like macrophages. Embryonic/fetal macrophages are M2‐like, and this may promote scar‐free wound healing. In the present study, we asked whether atopical application of ex vivo generated, embryonic stem cell–derived macrophages (ESDM) improve wound healing in mice. ESDM were tested side by side with bone marrow–derived macrophages (BMDM). Compared to BMDM, ESDM resembled a less inflammatory and more M2‐like macrophage subtype as indicated by their reduced responsiveness to lipopolysaccharide, reduced expression of Toll‐like receptors, and reduced bacterial phagocytosis. Despite this anti‐inflammatory phenotype in cell culture, ESDM prolonged the healing of deep skin wounds even more than BMDM. Healed wounds had more scar formation compared to wounds receiving BMDM or cell‐free treatment. Our data indicate that atopical application of ex vivo generated macrophages is not a suitable cell therapy of dermal wounds. 相似文献
85.
Ross Steffen Cosima Suter Flach Patricia Oesterhelweg Lars Thali Michael Bolliger Stephan 《Legal medicine (Tokyo, Japan)》2010,12(6):271-275
As an Alpine country, Switzerland has not only a thriving mountaineering tourist industry, but also many mountaineering casualties. At the request of the state attorney, most of the victims undergo only an external inspection without autopsy. One of the main tasks of the forensic pathologist under these circumstances is the correct identification of the deceased for a fast release to their kin. Nevertheless, detailed knowledge of the injuries sustained may lead to improved safety measures, such as better protective equipment.In this study, we examined the feasibility of using cross-sectional imaging with postmortem multi-slice computed tomography (MSCT) to detect lesions of the skeletal structures and internal organs. For this purpose, we used whole-body MSCT to examine 10 corpses that suffered fatal falls from great height while climbing in the Swiss part of the European Alps from the years 2007 to 2009.We conclude that postmortem CT imaging is a valuable tool for dental identification and is superior to plain X-rays as a viable compromise between a solely external legal inspection and an autopsy because it delivers otherwise irretrievable additional internal findings non-invasively. This fact is of great importance in cases where an autopsy is refused. 相似文献
86.
R. Illig C. DeCampo M. R. Lang-Muritano A. Prader T. Torresani E. A. Werder U. Willi L. Schenkel 《European journal of pediatrics》1990,150(2):86-91
Transdermal 17-oestradiol administration (17-E2), used mainly in menopausal women, allows a continuous 17-E2 delivery through the skin into the systemic circulation, avoiding intestinal and hepatic passage. In order to explore whether transdermal 17-E2 could be used for the induction of puberty, 17-E2 patches with low dose delivery were administered in nine prepubertal girls with Turner syndrome (bone age >10.5 years) for a mean period of 2.2 years. Treatment schedule: 5 g/day for 6–9 months, 10 g/day for 6–9 months, 25 g/day for long-term substitution; addition of cyclic gestagen p.o. after 18–24 months. Breast development started within 3 months of therapy and menstruation occurred after 2 years. Growth rate increased from 3.2 to 5.0 cm/year during the 1st year of therapy, height prediction did not change. Serum oestradiol (E2) and urinary E2 conjugates increased proportionally with 17-E2 doses, serum oestrone (E1) rose much less. The possibility to imitate time course, clinical events and hormonal changes of normal puberty, the absence of adverse drug reactions and the excellent acceptance and easy mode of application suggest that transdermal 17-E2 is optimally suited for hormonal substitution in girls with hypogonadism.Presented in part at the Annual Meeting of the European Society for Paediatric Endocrinology and the LWSPE, Jerusalem November 1989 相似文献
87.
N. Benador W. Mannhardt D. Schranz C. Braegger S. Fanconi S. Hassam V. Talebzadeh J. Cox S. Suter 《European journal of pediatrics》1990,149(8):555-559
We report three cases of neonatal herpes simplex virus (HSV) infection presenting as fulminant hepatitis. None of the patients had clear risk factors for HSV infection and they all died. Antiviral treatment for HSV is currently available but must be administered early in the course of the disease before irreversible liver tissue damage is present. Since the diagnosis may be difficult to establish, we wish to draw the attention of clinicians to the presentation of neonatal HSV infection and suggest that in such cases viral cultures, including culture of liver tissue, should be obtained early and antiviral treatment administered while awaiting the culture results. 相似文献
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89.
Interference of plant extracts,phytoestrogens and antioxidants with the MTT tetrazolium assay 总被引:6,自引:0,他引:6
Bruggisser R von Daeniken K Jundt G Schaffner W Tullberg-Reinert H 《Planta medica》2002,68(5):445-448
The MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay is a widely used screening method to measure cell viability and proliferation. When testing the effects of kaempferol on breast cancer cell number (crystal violet staining) and viability (MTT tetrazolium assay) conflicting results were obtained. Cell number decreased but MTT formazan formation increased, suggesting a direct interaction of kaempferol with the MTT tetrazolium reduction. Direct reductive potential was observed in a cell-free system for the presumptive phytoestrogens kaempferol and resveratrol, and extracts of Hypericum perforatum L. and Cimicifuga racemosa L. All agents led to instantaneous dark blue formazan formation in the absence of cells. Additionally, antioxidants such as ascorbic acid, vitamin E and N-acetylcysteine interfered with the MTT tetrazolium assay. When MCF7 and HS578 cells treated with kaempferol were washed before addition of MTT tetrazolium, the direct reduction of dye was reduced significantly. These results indicate that the MTT tetrazolium assay may lead to false positive results when testing natural compounds with intrinsic reductive potential. 相似文献
90.
Suter AH 《AIHA journal : a journal for the science of occupational and environmental health and safety》2002,63(6):768-789
More than one-half million construction workers are exposed to potentially hazardous levels of noise, yet federal and state Occupational Safety and Health Administration (OSHA) programs provide little incentive to protect them against noise-induced hearing loss. Construction noise regulations lack the specificity of general industry noise regulations. In addition, problems that characterize the construction industry, such as worker mobility and the large proportion of small businesses, make implementing hearing conservation measures more difficult. The apparent severity of exposure depends greatly on the measurement method, with the 3-dB exchange rate almost always showing higher average exposure levels than the 5-dB (OSHA) rule. Construction workers demonstrate hearing threshold levels that generally conform to those expected in manufacturing. The prevalence of hearing protection device (HPD) use among U.S. construction workers is very poor, partly because of perceived difficulties in hearing and understanding speech communication and warning signals. In addition, masking by noise of necessary communication and warning signals is of particular concern in construction, where recent research demonstrated the association between fatalities and the failure to hear reverse alarms. Judicial use of HPDs is of the utmost importance, along with avoiding overattenuation, selecting HPDs with uniform attenuation, and using noise-attenuating communication systems when possible. A successful hearing conservation program in British Columbia can serve as a model for the United States, with a long-standing positive safety culture, a high percentage of HPD use, improvement in average hearing threshold levels over the last decade, and a centralized record-keeping procedure, which helps solve the problem of worker mobility. However, controlling construction noise at the source is the most reliable way to protect worker hearing. U.S. manufacturers and contractors should benefit from the activities of the European Community, where noise control and product labeling in construction has been carried out for more than 20 years. 相似文献