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51.
Formalinized Mycoplasma pulmonis was used to immunize 3 different age groups of Fischer 344 rats. A specific antibody to this antigen was detected in both saliva and lung lavage fluids and differences were noted in the elicitation of secretory antibody between the different ages of the animals. Few statistical differences were noted between the three age groups for salivary IgG responses to M. pulmonis, regardless of the dosage given, even though all responses were greater than their respective control groups. The principal differences among the three age groups were noted in the kinetics of the response, that is, the amount of time that was necessary to produce a peak response. The younger group of animals took less time to produce a peak response than the older two groups, even though the magnitude of the response was lower. Salivary IgA responses to M. pulmonis appeared predominantly as a primary response, particularly in the senescent animals. Secondary salivary IgA responses were not significantly greater than their respective primary responses, suggesting that secretory IgA did not display classic anamnestic responses that were observed with salivary IgG. As with IgG responses, the senescent animals took longer to produce a peak salivary IgA response when compared to the other age groups. Lung lavage IgG responses, normalized to total protein, were greatest in the youngest group of animals and appeared to diminish as the age of the animal increased. In contrast, lung lavage IgA responses to M. pulmonis were of a greater magnitude in the senescent animals. These studies suggest that senescent animals are capable of eliciting a humoral immune response in mucosal secretions to Mycoplasma pulmonis. However, differences noted with regard to disease severity and mortality to respiratory mycoplasmosis in senescent animals may result from intrinsic defects in the quality of the humoral response or as a consequence of deficient cellular responses to this pathogen. 相似文献
52.
Krüger S Bier A Plaschke J Höhl R Aust DE Kreuz FR Pistorius SR Saeger HD Rothhammer V Al-Taie O Schackert HK 《Human mutation》2004,24(4):351-352
Hereditary nonpolyposis colorectal cancer (HNPCC) is one of the most common hereditary cancer-susceptibility syndromes. Germline mutations in mismatch repair genes are associated with the clinical phenotype of HNPCC. We report ten novel germline mutations, three in MSH2 and seven in MLH1. All but one mutation have been found in families fulfilling criteria of the Bethesda guidelines; four of them additionally fulfilled the Amsterdam criteria I or II. Eight mutations were considered pathogenic and predictive diagnostics in healthy family members at risk shall be undertaken; these include five frameshift mutations leading to premature stop codons, in MSH2: c.1672delT (p.S558Xfs) and c.2466_2467delTG (p.C822X) and in MLH1: c.1023delG (p.R341Xfs), c.1127_1128dupAT (p.K377Xfs) and c.1310delC (p.P437Xfs); three mutations leading to splice aberrations, in MSH2: c.1661G>C (r.1511_1661del) and in MLH1: c.677+3A>C (r.589_677del) and c.1990-2A>G predicted to result in a splice site defect. The remaining two mutations are unclassified variants with assumed pathogenicity: one missense mutation in the highly conserved ATPase domain of MLH1 (c.122A>G [p.D41G]) and one in-frame insertion of twelve nucleotides in MLH1 (c.2155_2156insATGTGTTCCACA [p.I719delinsNVFHI]). These two mutations were not found in 102 alleles of healthy control individuals. The corresponding tumors from all patients showed a high level of microsatellite instability (MSI-H). Immunohistochemistry (IHC) revealed complete loss of expression of the affected protein in the tumor cells from all but three patients. The tumors from the patients with the mutations c.1127_1128dupAT and c.1990-2A>G showed a reduction of expression of the MLH1-protein, rather than complete loss. In the tumor from the patient with the missense mutation c.122A>G [p.D41G] a normal expression of the proteins coded by MLH1 and MSH2 was noticed. 相似文献
53.
Cramer LG Pitt SR Rehbein S Gogolewski RP Kunkle BN Langhoff WK Bond KG Maciel AE 《Parasitology research》2000,86(11):944-946
Six studies were conducted to evaluate the persistent efficacy of eprinomectin pour-on against experimental challenges with
infective nematode larvae in calves. In each study, calves were randomly assigned to one untreated group and up to four test
groups, which were treated with eprinomectin at 500 μg/kg body weight at weekly intervals before single bolus challenge. The
calves were necropsied approximately 4 weeks after challenge infection for nematode recovery. Eprinomectin pour-on provided
≥90% efficacy against challenge with Haemonchus placei, Trichostrongylus axei and T. colubriformis at 21 days after treatment and against Cooperia oncophora, C. punctata, C. surnabada, Dictyocaulus viviparus, Nematodirus helvetianus, Oesophagostomum radiatum and Ostertagia ostertagi at 28 days after treatment.
Received: 14 April 2000 / Accepted: 18 May 2000 相似文献
54.
Malaria prophylaxis and self-therapy in airline crews 总被引:2,自引:0,他引:2
R Steffen F Holdener R Wyss L Nurminen 《Aviation, space, and environmental medicine》1990,61(10):942-945
The risk of malaria infection in airline crews is estimated to be 0.5 per 1,000 persons per night in areas with high levels of malaria transmission. Routine chemoprophylaxis for years is not recommended because of possible side effects. Airline crews should therefore use appropriate measures to prevent mosquito bites. In addition, they may need to carry "standby" medication with them to be used for presumptive treatment of a febrile illness if medical attention is not readily available. 相似文献
55.
Hans-Reinhard Zerkowski Andrea Broede Klaus Kunde Steffen Hillemann Ellen Schäfer Magdalene Vogelsang Martin C. Michel Otto-Erich Brodde 《Naunyn-Schmiedeberg's archives of pharmacology》1993,347(4):347-352
Summary The receptor systems through which serotonin (5-HT), histamine, angiotensin II and endothelin increase the force of contraction were studied in isolated right atria from patients without apparent heart failure.All agonists increased the atrial force of contraction in a concentration-dependent manner; maximal effects, however, were significantly less than those evoked by isoprenaline or Ca2+. 5-HT and histamine, but not angiotensin II and endothelin, activated adenylate cyclase, whereas endothelin and angiotensin II stimulated inositol phosphate generation. Experiments with subtype-selective antagonists revealed that histamine effects were mediated by H2-receptors (sensitive to ranitidine), 5-HT-effects by 5-HT4-receptors (sensitive to SDZ 205-557) and angiotensin II effects by AT1-receptors (sensitive to losartan).We conclude that in human right atria the force of contraction can be increased by cyclic AMP-dependent (histamine, 5-HT) and -independent (angiotensin II, endothelin) pathways. Compared to -adrenoceptors, however, all other receptor systems increase the force of contraction only submaximally indicating that the -adrenoceptor pathway is the most important physiological mechanism to regulate force of contraction and/or heart rate in the human heart.Correspondence to O. E. Brodde at the above address 相似文献
56.
Lukas Wettstein Patrick Immenschuh Tatjana Weil Carina Conzelmann Yasser Almeida-Hernández Markus Hoffmann Amy Kempf Inga Nehlmeier Rishikesh Lotke Moritz Petersen Steffen Stenger Frank Kirchhoff Daniel Sauter Stefan Pöhlmann Elsa Sanchez-Garcia Jan Münch 《Journal of medical virology》2023,95(1):e28124
Host cell proteases such as TMPRSS2 are critical determinants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) tropism and pathogenesis. Here, we show that antithrombin (AT), an endogenous serine protease inhibitor regulating coagulation, is a broad-spectrum inhibitor of coronavirus infection. Molecular docking and enzyme activity assays demonstrate that AT binds and inhibits TMPRSS2, a serine protease that primes the Spike proteins of coronaviruses for subsequent fusion. Consequently, AT blocks entry driven by the Spikes of SARS-CoV, MERS-CoV, hCoV-229E, SARS-CoV-2 and its variants of concern including Omicron, and suppresses lung cell infection with genuine SARS-CoV-2. Thus, AT is an endogenous inhibitor of SARS-CoV-2 that may be involved in COVID-19 pathogenesis. We further demonstrate that activation of AT by anticoagulants, such as heparin or fondaparinux, increases the anti-TMPRSS2 and anti-SARS-CoV-2 activity of AT, suggesting that repurposing of native and activated AT for COVID-19 treatment should be explored. 相似文献
57.
Heitmann BL Harris JR Lissner L Pedersen NL 《The American journal of clinical nutrition》1999,69(4):597-602
BACKGROUND: Obesity is influenced by genetic and environmental factors. Additionally, synergistic effects of genes and environments may be important in the development of obesity. OBJECTIVE: The aim of this study was to test for genetic effects on food consumption frequency, food preferences, and their interaction with subsequent weight gain. DESIGN: Complete data on the frequencies of consumption of 11 foods typical of the Swedish diet were available for 98 monozygotic and 176 dizygotic twin pairs aged 25-59 y who are part of the Swedish Twin Registry. The data were collected in 1973 as part of a questionnaire study. Body mass index was measured in 1973 and again in 1984. RESULTS: There was some evidence that genetic effects influenced the frequency of intake of some foods. Similarity among monozygotic twins exceeded that among dizygotic twins for intake of flour and grain products and fruit in men and women, intake of milk in men, and intake of vegetables and rice in women, suggesting that genes influence preferences for these foods. Analyses conducted for twins reared together and apart also suggested greater monozygotic than dizygotic correlations, but cross-twin, cross-trait correlations were all insignificant, suggesting that the genes that affect consumption frequencies are not responsible for mediating the relation between the frequency of intake and weight change. CONCLUSIONS: Genetic effects and the frequency of intake are independently related to change in body mass index. However, there was no suggestion of differential genetic effects on weight gain that were dependent on the consumption frequency of the foods studied. 相似文献
58.
Sarraf-Yazdi S Sheng H Grocott HP Bart RD Pearlstein RD Steffen RP Warner DS 《Brain research》1999,826(2):381-180
This study examined the effect of a pharmacologically induced rightward shift in the partial pressure of oxygen at which 50% of hemoglobin is saturated (P50) on outcome from transient focal cerebral ischemia in the rat. Halothane anesthetized rats (n=20 per group) were given saline or a single 15-min infusion of 150 mg/kg RSR13 (2-[4-[[3,5-dimethylanilino) carbonyl]methyl]phenoxy]-2-methylproprionic acid) intravenously before or 30 min after onset of 75 min of middle cerebral artery filament occlusion (MCAO). Seven days later, severity of hemiparesis and cerebral infarct size were examined. RSR13 alone did not significantly improve outcome. Conscious normothermic rats (n=12 per group) were also given RSR13 (150 mg/kg) or 0.9% NaCl intravenously and subjected to 75 min of MCAO with 7 days of recovery. Again, RSR13 alone did not significantly reduce infarct size or improve neurologic score. A dose-response curve for dizocilpine (MK-801) was then constructed in conscious normothermic rats subjected to 75 min of MCAO. Dizocilpine (0.5 mg/kg i.v.) caused a 90% reduction in mean infarct size while 0.25 mg/kg reduced infarct size by 48%. Other rats were then subjected to 75 min of MCAO after being given dizocilpine (0.25 mg/kg i.v.; n=18) or RSR13 (150 mg/kg i.v. )+dizocilpine (0.25 mg/kg i.v.; n=15). RSR13+dizocilpine resulted in smaller cortical infarct volume (8+/-14 mm3 vs. 34+/-37 mm3, p<0.02) and total cerebral infarct volume (46+/-28 mm3 vs. 81+/-60 mm3, p<0. 05) compared to dizocilpine alone, respectively. We conclude that a pre-ischemic peak increase in P50 of approximately 25 mmHg alone is insufficient to reduce focal ischemic injury, but may be advantageous when used in conjunction with other neuroprotective agents. 相似文献
59.
J. Lissner 《European radiology》1996,6(2):249-250
News of the European Affiliated Socities
European society of Uroradiology (ESUR)Newsletter 1996, No. 1 相似文献60.
Organizational commitment on the part of nursing home employees can be a determinant of service quality. Proper design of health care jobs and clarity of roles make employees feel more dedicated to their jobs, enable them to do their jobs well, and enhance family members' evaluations of nursing home care. When management develops a dynamic, interactive, high-quality environment, nursing home employees feel encouraged to report shortcomings without fear because they are involved in the process. 相似文献