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1.
Prostaglandin F2 alpha enhancement of capsaicin induced cough in man: modulation by beta 2 adrenergic and anticholinergic drugs. 总被引:10,自引:7,他引:3 下载免费PDF全文
The effect of inhaled prostaglandin (PG) F2 alpha on the response to the inhaled tussive agent capsaicin was investigated in normal subjects. Seven subjects inhaled three breaths of four doses of capsaicin (0.3, 0.6, 1.2, and 2.4 nmol) before and immediately after inhaling PGF2 alpha (0.1 mumol) or placebo (0.15M NaCl) on separate days. The numbers of capsaicin induced coughs were greater after PGF2 alpha (mean 42.3 coughs) than after 0.15M sodium chloride (30.1). Visual analogue scores (0-10 on a 10 cm continuous scale) showed that capsaicin was more irritant after PGF2 alpha than after saline. Total respiratory resistance (Rrs), measured by the forced oscillation technique, was unaltered throughout the study. A double blind, placebo controlled study of the effects of inhaled salbutamol (200 micrograms, 0.6 mumol) and ipratropium bromide (40 micrograms, 0.1 mumol) on cough induced by capsaicin (2.4 nmol) and by PGF2 alpha (0.1 mumol) and on PGF2 alpha augmented, capsaicin induced coughing was performed in seven subjects. Neither drug had any effect on capsaicin induced coughing. Salbutamol reduced coughing due to PGF2 alpha (mean 7.7 coughs after salbutamol, 9.3 after placebo) but ipratropium bromide did not (mean 6.9 coughs after ipratropium bromide, 6.6 after placebo). Salbutamol also inhibited the augmentation of the capsaicin induced cough that followed inhalation of PGF2 alpha (mean augmentation 1.9 coughs after salbutamol, 4.1 after placebo), whereas ipratropium bromide did not (augmentation 1.7 coughs after ipratropium bromide, 2.7 after placebo). No changes in Rrs were seen after PGF2 alpha or either drug. Thus salbutamol reduces PGF2 alpha induced cough and the augmentation of capsaicin induced cough that follows PGF2 alpha. 相似文献
2.
Kathryn Nichol Sean P. Deeny Joseph Seif Kevin Camaclang Carl W. Cotman 《Alzheimer's & dementia》2009,5(4):287-294
BackgroundHuman studies on exercise, cognition, and apolipoprotein E (APOE) genotype show that ε4 carriers may benefit from regular physical activity.MethodsWe examined voluntary wheel-running, memory, and hippocampal plasticity in APOE ε3 and APOE ε4 transgenic mice at 10–12 months of age.ResultsSedentary ε4 mice exhibited deficits in cognition on the radial-arm water maze (RAWM), a task dependent on the hippocampus. Six weeks of wheel-running in ε4 mice resulted in improvements on the RAWM to the level of ε3 mice. Hippocampal brain-derived neurotrophic factor (BDNF) levels were similar in ε3 and ε4 mice, and after exercise BDNF was similarly increased in both ε3 and ε4 mice. In sedentary ε4 mice, tyrosine kinase B (Trk B) receptors were reduced by 50%. Exercise restored Trk B in ε4 mice to the level of ε3 mice, and in ε4 mice, exercise dramatically increased synaptophysin, a marker of synaptic function.ConclusionsOur results support the hypothesis that exercise can improve cognitive function, particularly in ε4 carriers. 相似文献
3.
Frequency of adverse reactions to influenza vaccine in the elderly. A randomized, placebo-controlled trial 总被引:7,自引:0,他引:7
Concern about side effects constitutes a major deterrent to patient compliance with influenza vaccination, yet there is a paucity of data about the occurrence of adverse reactions in the population targeted for immunization. We conducted a randomized, double-blind, crossover trial to compare the frequency of adverse reactions following administration of 1988-1989 trivalent split-antigen influenza vaccine and saline placebo. Outpatient veterans 65 years of age or over (n = 336) were recruited by mail and were randomly assigned to receive vaccine followed 2 weeks later by placebo injection or placebo followed 2 weeks later by vaccine. There was no significant difference between influenza vaccine and placebo with respect ot the proportion of subjects reporting disability or systemic symptoms. 相似文献
4.
Hantavirus Pulmonary Syndrome: Pathogenesis of an Emerging Infectious Disease 总被引:23,自引:1,他引:23 下载免费PDF全文
Sherif R. Zaki Patricia w. Greer Lisa M. Coffield Cynthia S. Goldsmith Kurt B. Nolte Kathy Foucar Richard M. Feddersen Ross E. Zumwalt Gayle L. Miller Ali S. Khan Pierre E. Rollin Thomas G. Ksiazek Stuart T. Nichol Brian W.J. Mahy Clarence J. Peters 《The American journal of pathology》1995,146(3):552-579
5.
Traditional approaches to generating tissue-engineered arteries in vitro rely on expansion of cells in culture to seed appropriate scaffolds. In most envisioned applications, small autologous blood vessels would be harvested and used as a source for these cells. We propose that small autologous arteries, not the cells derived from them, may be an attractive starting point for engineered arteries. This approach capitalizes on the ability of intact arteries to grow and remodel in response to chronic changes in their mechanical environment. Carotid arteries from juvenile (approximately 30-kg) pigs were stretched longitudinally in an ex vivo perfusion system over 9 days. This resulted in a 40% increase in artery length at physiological longitudinal stress and a 20 +/- 3% increase when unstressed. Control arteries were perfused for 9 days ex vivo at their physiological loaded length. Control and elongated arteries displayed native appearance (macroscopic and histological), excellent viability (cellularity and mitochondrial activity), normal vasoactivity, and similar mechanical properties (ultimate stress and ultimate strain) as compared with freshly harvested arteries. Growth, as opposed to just redistribution of existing mass, contributed to elongation as evidenced by an increase in artery weight. Results on elongation of arteries from neonatal and adolescent pigs are also presented and discussed. 相似文献
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8.
Hemodynamic Conditions Alter Axial and Circumferential Remodeling of Arteries Engineered <Emphasis Type="Italic">Ex Vivo</Emphasis> 总被引:3,自引:0,他引:3
We previously demonstrated that growth and remodeling was stimulated in arteries elongated ex vivo using step increases in axial strain. Viability and vasoactivity were similar to fresh arteries, however there was a substantial decrease in the ultimate circumferential stress. To test the hypothesis that the subphysiological perfusion conditions (i.e., low pressure and flow) previously used caused the reduction, arteries were subjected to the identical elongation protocol (50% increase over 9 days) while being perfused with physiological levels of flow, viscosity and pulsatile pressure. A significant increase in unloaded length was achieved by elongation under both perfusion conditions, although the increase was less under physiological (7 ± 1%) than under subphysiological conditions (19 ± 2%, p < 0.005). When length at physiological stress was estimated using mechanical testing data the values were similar. The ultimate circumferential stress of arteries elongated under physiological conditions was increased (33%), whereas the ultimate axial stress was decreased (50%) as compared with arteries elongated under subphysiological conditions. Elongated arteries under both perfusion conditions showed significant increases in proliferation and collagen mass, and similar viability and appearance to fresh arteries. These data suggest that there is substantial cross-talk between perfusion conditions and axial strain that modulates arterial remodeling and length. 相似文献
9.
McKevitt Elaine Cheifetz Rona DeVries Kimberly Laws Alison Warburton Rebecca Gondara Lovedeep Lohrisch Caroline Nichol Alan 《Annals of surgical oncology》2021,28(11):5950-5957
Annals of Surgical Oncology - The SSO Choosing Wisely campaign recommended selective sentinel lymph node biopsy (SLNB) in clinically node-negative women aged ≥ 70 years with ER+ breast... 相似文献
10.
Beneficial effects of treatment of nicotine dependence during an inpatient substance abuse treatment program 总被引:2,自引:0,他引:2
The Minneapolis Department of Veterans Affairs Medical Center began an intervention for tobacco use in its inpatient substance dependency treatment program on June 19, 1988, including an institutional smoke-free policy and a smoking cessation program. Sequential substance-dependent patients admitted before institution of the policy (n = 455) were compared with patients admitted after institution of the policy (n = 457). Patients completed self-administered questionnaires regarding smoking practices and attitudes. Seventy-six percent of patients were current cigarette smokers. Fifty-eight percent of patients after institution of the policy described themselves as "not smoking regularly," compared with 19% of patients admitted before the institution of the policy. Similar proportions of patients admitted before and after the institution of the policy believed that quitting smoking would threaten recovery. Forty-one percent of patients hospitalized after institution of the policy abstained from smoking for more than 1 week during their hospital stay. Rates of early termination of treatment did not change. We conclude that concurrent intervention for nicotine addiction during inpatient treatment of substance dependence is associated with a temporary reduction in smoking and increased motivation to quit smoking. 相似文献