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51.
The sand rat (psammomys obesus) as an experimental animal in studies of diabetes mellitus 总被引:1,自引:0,他引:1
Donald B. Hackel Eileen Mikat Harold E. Lebovitz Knut Schmidt-Nielsen Edward S. Horton Thomas D. Kinney 《Diabetologia》1967,3(2):130-134
Summary The sand rat has some unique attributes, which make it a valuable experimental animal. The occurrence of increased plasma insulin levels and of hyperglycemia is linked to an increased food intake. As in the human maturity-onset type diabetes, there seems to be an element of insulin resistance, and this can be demonstratedin vitro by the relative unresponsiveness of sand rat adipose tissue to increasing doses of pork insulin. Prophylactic treatment with acetohexamide seems to have some protective effect against the diabetogenic results of a high calory diet. — It is expected that the diabetic syndrome in sand rats, which can be so easily induced by dietary manipulation, will be a valuable tool in helping to clarify some of the possible mechanisms in the syndrome of diabetes mellitus.This work was carried out during the tenure of Research Career Awards from the U. S. Public Health Service to Drs.Hackel (HE-K6-14, 188) andSchmidt-Nielsen, (K6-GM-21, 522) a Career Development Award to Dr.Lebovitz (K3-AM-17, 954), and a Research Fellowship to Dr.Horton (F3-AM-32, 326); supported by grants from the U. S. Public Health Service (AM-08949, AM-1324, and HE-0228), Eli Lilly Co., the Duke University Research Council, and the Mary Duke Biddle Foundation. 相似文献
52.
Grarup N Andreasen CH Andersen MK Albrechtsen A Sandbaek A Lauritzen T Borch-Johnsen K Jørgensen T Schmitz O Hansen T Pedersen O 《The Journal of clinical endocrinology and metabolism》2008,93(6):2294-2299
CONTEXT: Hepatic lipase plays a pivotal role in the metabolism of high-density lipoprotein (HDL) and low-density lipoprotein by involvement in reverse cholesterol transport and the formation of atherogenic small dense low-density lipoprotein. OBJECTIVES: The objective was to investigate the impact of variants in LIPC on metabolic traits and type 2 diabetes in a large sample of Danes. Because behavioral factors influence hepatic lipase activity, we furthermore examined possible gene-environment interactions in the population-based Inter99 study. DESIGN: The LIPC -250G>A (rs2070895) variant was genotyped in the Inter99 study (n = 6070), the Anglo-Danish-Dutch Study of Intensive Treatment in People with Screen Detected Diabetes in Primary Care Denmark screening cohort of individuals with risk factors for undiagnosed type 2 diabetes (n = 8662), and in additional type 2 diabetic patients (n = 1,064) and glucose-tolerant control subjects (n = 360). RESULTS: In the Inter99 study, the A allele of rs2070895 associated with a 0.057 mmol/liter [95% confidence interval (CI) 0.039-0.075] increase in fasting serum HDL-cholesterol (HDL-c) (P = 8 x 10(-10)) supported by association in the Anglo-Danish-Dutch Study of Intensive Treatment in People with Screen Detected Diabetes in Primary Care study [0.038 mmol/liter per allele (95% CI 0.024-0.053); P = 2 x 10(-7)). The allelic effect on HDL-c was modulated by interaction with self-reported physical activity (P(interaction) = 0.002) because vigorous physically active homozygous A-allele carriers had a 0.30 mmol/liter (95% CI 0.22-0.37) increase in HDL-c compared with homozygous G-allele carriers. CONCLUSIONS: We validate the association of LIPC promoter variation with fasting serum HDL-c and present data supporting an interaction with physical activity implying an increased effect on HDL-c in vigorous physically active subjects carrying the -250 A allele. This interaction may have potential implications for public health and disease prevention. 相似文献
53.
Maria Aamelfot Simon C. Weli Ole B. Dale Erling O. Koppang Knut Falk 《Journal of anatomy》2013,222(5):547-557
Endothelial cells (ECs) line the luminal surfaces of the cardiovascular system and play an important role in cardiovascular functions such as regulation of haemostasis and vasomotor tone. A number of fish and mammalian viruses target these cells in the course of their infection. Infectious salmon anaemia virus (ISAV) attacks ECs and red blood cells (RBCs) of farmed Atlantic salmon (Salmo salar L.), producing the severe disease of infectious salmon anaemia (ISA). The investigation of ISA has up to now been hampered by the lack of a functional marker for ECs in Atlantic salmon in situ. In this study, we report the characterisation and use of a novel monoclonal antibody (MAb) detecting Atlantic salmon ECs (e.g. vessel endothelium, endocardial cells and scavenger ECs) and RBCs. The antibody can be used with immunohistochemistry, IFAT and on Western blots. It appears that the epitope recognised by the antibody is associated with the ISAV cellular receptor. Besides being a tool to identify ECs in situ, it could be useful in further studies of the pathogenicity of ISA. Finally, the detection of an epitope shared by ECs and RBCs agrees with recent findings that these cells share a common origin, thus the MAb can potentially be used to study the ontogeny of these cells in Atlantic salmon. 相似文献
54.
Doreen Siegels Annice Heratizadeh Susanne Abraham Jonas Binnmyr Knut Brockow Alan D. Irvine Susanne Halken Charlotte G Mortz Carsten Flohr Peter Schmid-Grendelmeier Lauri-Ann Van der Poel Antonella Muraro Stephan Weidinger Thomas Werfel Jochen Schmitt the European Academy of Allergy Clinical Immunology Atopic Dermatitis Guideline group 《Allergy》2021,76(4):1053-1076
55.
Darab Ghadimi Michael de Vrese Michael Ebsen Christoph Röcken Sven Olaf Frahm Janine Zahlten Regina Fölster-Holst Knut J. Heller Wilhelm Bockelmann 《Immunobiology》2021,226(1):152028
Background and AimsPglyrp3 is a bactericidal innate immunity protein known to sustain the habitual gut microbiome and protect against experimental colitis. Intestinal inflammation and metaflammation are commonly associated with a marked reduction of commensal bifidobacteria. Whether Pglyrp3 and bifidobacteria interact synergistically or additively to alleviate metaflammation is unknown. We investigated the extent to which Pglyrp3 and bifidobacteria regulate metaflammation and gut bacterial dysbiosis in DSS-induced mouse models of intestinal inflammation.Material & Methods8–10 weeks old male mice were used. In both WT and Pglyrp3 ?/? experiments, the mice were randomly divided into three groups of 16 mice per group: (1) a control group receiving sterile tap water, (2) an experimental group receiving sterile tap water supplemented with only 5% DSS, and (3) an experimental group receiving sterile tap water supplemented with 5% DSS and 1 × 109 CFU/ml of Bifidobacterium adolescentis (B.a.) for 7 days. Wild-type (WT) littermates of the respective gene (i.e. Pglyrp3) were used as controls throughout the study. Clinical signs of general health and inflammation were monitored daily. Faecal pellet samples were analysed by qRT-PCR for microbial composition. Histology of relevant organs was carried out on day 8. Metabolic parameters and liver inflammation were determined in serum samples.ResultsIntestinal inflammation in mice of group 2 were significantly increased compared to those of control group 1. There was a significant difference in mean scores for inflammation severity between DSS-treated WT and DSS-treated Pglyrp3 ?/? mice. Buildup of key serum metabolic markers (cholesterol, triglyceride and glucose) was set off by colonic inflammation. qRT-PCR quantification showed that DSS significantly decreased the Clostridium coccoides and Bifidobacterium cell counts while increasing those of Bacteroides group in both WT and Pglyrp3 ?/? mice. These manifestations of DSS-induced dysbiosis were significantly attenuated by feeding B.a. Both the local and systemic ill-being of the mice alleviated when they received B.a.DiscussionThis study shows that Pglyrp3 facilitates recognition of bifidobacterial cell wall-derived peptidoglycan, thus leading additively to a reduction of metaflammation through an increase in the number of bifidobacteria, which were able to mitigate intestinal immunopathology in the context of Pglyrp3 blockade. 相似文献
56.
57.
Ovrebø KK Svanes K Aase S Grong K Kvinnsland S Sørbye H 《Digestive diseases and sciences》2002,47(10):2354-2369
The mucosal changes by which duodenogastric reflux may predispose to gastric cancer have not been fully clarified. In this study in rats, duodenal fluid was directed into the stomach through a gastroenterostomy (jejunal reflux, N = 29) or through the pylorus (pyloric reflux, N = 30) and compared with 30 controls. Twenty-four weeks later the stomach was exposed to N-[3H]methyl-N-nitro-N-nitrosoguanidine ([3H]MNNG). The corpus mucosa was examined for proliferating cells (bromodeoxyuridine labeled) and cells at risk of methyl-N-nitro-N-nitrosoguanidine-induced carcinogenesis (cells labeled with bromodeoxyuridine and [3H]MNNG). The number of double-labeled cells increased from 0.8 ± 0.1/mm mucosa in the control group to 5.2 ± 0.9 in the jejunal reflux group (P < 0.05) and 2.7 ± 0.5 in the pyloric reflux group (P < 0.05). An erosion or ulcer appeared at the gastroenterostomy in 52% of animals with jejunal reflux and 17% of those with pyloric reflux (P < 0.006). Within erosions the mean number of double-labeled cells was 9.6 ± 2.2 in the jejunal reflux group and 7.7 ± 4.8 in the pyloric reflux group, and significantly higher than in the nonlesion area of the mucosa (0.6 ± 0.2 and 0.8 ± 0.3). In erosions the distance between the gastric lumen and the proliferating cells was significantly shorter and the cell proliferation significantly higher than in the nonlesion area of the mucosa. We conclude that duodenogastric reflux increases the penetration of [3H]MNNG into the corpus mucosa of rats and also induces mucosa lesions, which further increase the penetration of [3H]MNNG into the corpus mucosa. 相似文献
58.
59.
Michael Kummer Knut Kirmse Otto W. Witte Jens Haueisen Knut Holthoff 《Biomedical optics express》2015,6(10):3678-3693
Two-photon laser-scanning microscopy enables to record neuronal network activity in three-dimensional space while maintaining single-cellular resolution. One of the proposed approaches combines galvanometric x-y scanning with piezo-driven objective movements and employs hardware feedback signals for position monitoring. However, readily applicable methods to quantify the accuracy of those feedback signals are currently lacking. Here we provide techniques based on contact-free laser reflection and laser triangulation for the quantification of positioning accuracy of each spatial axis. We found that the lateral feedback signals are sufficiently accurate (defined as <2.5 µm) for a wide range of scan trajectories and frequencies. We further show that axial positioning accuracy does not only depend on objective acceleration and mass but also its geometry. We conclude that the introduced methods allow a reliable quantification of position feedback signals in a cost-efficient, easy-to-install manner and should be applicable for a wide range of two-photon laser scanning microscopes.OCIS codes: (180.6900) Three-dimensional microscopy, (180.4315) Nonlinear microscopy, (170.0180) Microscopy, (170.2520) Fluorescence microscopy, (180.2520) Fluorescence microscopy 相似文献
60.
Knut Dehnert Ulla Raab Carmelo Perez-Alvarez Thomas Steffens Gabriele Bolte Hermann Fromme 《International journal of audiology》2015,54(10):665-673
Objective: To investigate total leisure noise exposure among adolescents and to assess its association with hearing. Design: Based on self-reported time spent on 19 leisure activities and associated mean sound pressure levels reported in the literature, total leisure noise exposure was evaluated and compared to noise at work limits (> 85 dB(A) = hazardous) in a cross-sectional survey. Tympanometry and pure-tone audiometry was performed in sound isolated rooms. Study sample: The study sample consists of 2143 pupils attending grade nine in any school in a German city 2009–2011 (mean age: 15.4 years; range: 13–19 years). Audiometric data were available for 1837 (85.8%) pupils (53.9% girls). Results: 41.9% of the 2143 adolescents who had provided self-reported data on leisure activities associated with noise exposure were estimated to be hazardously exposed to leisure time noise. The interaction of gender with total leisure time noise exposure was not significant. No association between leisure time noise exposure and audiometric notches could be detected. Conclusion: While hearing loss seems seldom in this age group, a high proportion of adolescents aged 15–16 years are exposed to noise levels during leisure time bearing long-term risks of hearing loss. 相似文献