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941.
Acellular Pertussis Vaccine Protects against Exacerbation of Allergic Asthma Due to Bordetella pertussis in a Murine Model
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Darren P. Ennis Joseph P. Cassidy Bernard P. Mahon 《Clinical and Vaccine Immunology : CVI》2005,12(3):409-417
The prevalence of asthma and allergic disease has increased in many countries, and there has been speculation that immunization promotes allergic sensitization. Bordetella pertussis infection exacerbates allergic asthmatic responses. We investigated whether acellular pertussis vaccine (Pa) enhanced or prevented B. pertussis-induced exacerbation of allergic asthma. Groups of mice were immunized with Pa, infected with B. pertussis, and/or sensitized to ovalbumin. Immunological, pathological, and physiological changes were measured to assess the impact of immunization on immune deviation and airway function. We demonstrate that immunization did not enhance ovalbumin-specific serum immunoglobulin E production. Histopathological examination revealed that immunization reduced the severity of airway pathology associated with sensitization in the context of infection and decreased bronchial hyperreactivity upon methacholine exposure of infected and sensitized mice. These data demonstrate unequivocally the benefit of Pa immunization to health and justify selection of Pa in mass vaccination protocols. In the absence of infection, the Pa used in this study enhanced the interleukin-10 (IL-10) and IL-13 responses and influenced airway hyperresponsiveness to sensitizing antigen; however, these data do not suggest that Pa contributes to childhood asthma overall. On the contrary, wild-type virulent B. pertussis is still circulating in most countries, and our data suggest that the major influence of Pa is to protect against the powerful exacerbation of asthma-like pathology induced by B. pertussis. 相似文献
942.
目的在生长发育高峰期观察不同矫治方法对骨性Ⅱ^1分类错(牙合)患者软组织侧貌的影响。方法选择骨性Ⅱ^1分类错(牙合)非拔牙儿童30例,随机分为2组,E组用方丝弓配合Ⅱ类牵引治疗16个月,T组用Twin—block功能矫治,治疗及观察16个月,以X线头影测量分析方法评价疗效。结果功能矫治组的软组织侧貌有明显改善,而固定矫治组改变不明显。结论功能矫治可获得良好的侧貌改善,但长期效果有待于进一步观察。 相似文献
943.
小鼠吗啡依赖纳洛酮催促戒断跳跃反应模型的建立 总被引:1,自引:0,他引:1
目的建立稳定的小鼠吗啡依赖纳洛酮催促戒断跳跃反应模型。方法小鼠连续皮下注射吗啡,以纳洛酮催促戒断跳跃反应为指标,调整吗啡给予天数(5,6,7,10d)、吗啡累积剂量(360,560,640,945,1100,1105,1200mg/kg)、每日给予吗啡的频数[一天二次(bid),一天三次(tid)]、纳洛酮催促紧前给予吗啡与否、以及纳洛酮剂量(10,20mg/kg),建立四个造模方案包括八个子方案。结果方案A、B2、C2吗啡组小鼠跳跃反应率未达100%;方案B1、C1、D2、D3、D4吗啡组小鼠跳跃次数变异系数较大。方案D1采用小鼠连续皮下注射倍增剂量的吗啡,tid×6d,每日每次剂量分别为5,10,20,40,80,160mg/kg;第7天皮下注射吗啡160mg/kg,3h后腹腔注射纳洛酮10mg/kg,吗啡组小鼠可产生显著的跳跃反应,与对照组比较差异有显著性(P<0.01),且变异系数小(CV为0.22),该方案吗啡依赖小鼠跳跃反应次数适度,离散度小。结论选用方案D1可建立稳定的小鼠戒断跳跃反应模型。 相似文献
944.
In vitro activity of azithromycin against clinical isolates of Legionella species. 总被引:7,自引:4,他引:3
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The activities of azithromycin, erythromycin, and ciprofloxacin against 21 Legionella isolates were measured by an agar dilution method and in macrophages. The MICs for 90% of strains tested were 2.0, 1.0, and 0.5 micrograms/ml for azithromycin, erythromycin, and ciprofloxacin, respectively. Azithromycin and ciprofloxacin were both bactericidal in the macrophage system, but erythromycin was bacteriostatic. 相似文献
945.
C.K. Kasper J.B. Graham P.B.A. Kernoff M.J. Larrieu K.A. Rickard and Prof. P.M. Mannucci 《Vox sanguinis》1989,56(3):141-144
Since 1982, when the World Federation of Hemophilia first published a document on the state of the art of hemophilia diagnosis and care, there have been lights and shadows in this field. Although the widespread infection of hemophiliacs with the human immunodeficiency virus (HIV) contaminating clotting factor concentrates is still a threatening and formidable shadow, the gloomy picture brought about by the AIDS epidemic is partially lightened by spectacular improvements in therapy and diagnosis. Carrier detection and first-trimester prenatal diagnosis can now be performed accurately in most kindreds by analysis of DNA of the factor VIII or IX genes. An important step forward towards the elimination of the risk of blood-borne infections transmitted by plasma products was recently made through the application of virucidal methods to clotting factor concentrates. Since HIV appears more vulnerable to such methods than the hepatitis viruses, currently available concentrates can be considered substantially free from the risk of transmitting HIV infection. Even though transmission of hepatitis is much reduced but not totally abolished, virucidal methods are continuously being improved, so that it can be foreseen that concentrates will become safer and safer. Finally, factor VIII produced by recombinant DNA technology is undergoing the first clinical trials in hemophiliacs. Hopefully, it will free from the risk of transmitting infections and will be available in sufficiently large amounts to meet the need of hemophiliacs worldwide. In 1982, the World Federation of Hemophilia published a message on the status of diagnosis and treatment of hemophilia. Since then, hemophilia care has been complicated by widespread infection of hemophiliacs with human immunodeficiency virus (HIV).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
946.
The effects of size and hydrophobicity of small (molecular weights below 2,000) polypeptides on their predominantly hydrophobic interactions with a neutral phospholipid monolayer were studied. The changes in surface pressure were determined when various concentrations of Gly, Gly-Gly-Gly,
-Ala,
-Ala-
-Ala-
-Ala,
-Ala-Gly-Gly-Gly-Gly,
-Phe-
-Leu-
-Glu-
-Glu-
-Leu, adrenocorticotropic hormone fragments 1–10 (ACTH-(1–10)), porcine β-lipotropin, -endorphin and human fibrinopeptide A were injected under dimyristoylphosphatidylcholine (DMPC) monolayers at an initial surface pressure of 10 dyne/cm. In all cases, when peptides with the same number of residues are compared, the concentration needed to increase the surface pressure of the film by 1 dyne/cm was inversely related to its hydrophobicity. A reasonably good correlation was found to exist between the calculated free energy of transfer of a polypeptide from ethanol to water (a measure of its hydrophobicity) and its ability to increase the surface pressure of the DMPC film (a measure of the extent of its interaction with the neutral lipid monolayer). 相似文献
947.
Multiple sources of calcium for contraction of the human urinary bladder muscle. 总被引:4,自引:4,他引:0
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C. A. Maggi S. Giuliani R. Patacchini D. Turini G. Barbanti A. Giachetti A. Meli 《British journal of pharmacology》1989,98(3):1021-1031
1. KCl, carbachol, neurokinin A and endothelin produced concentration-dependent contractions of mucosa-free muscle strips from the dome of the human urinary bladder. The maximal response to carbachol or neurokinin A exceeded that to KCl, while the maximal response to endothelin approached that to KCl. 2. Nifedipine (1 microM) abolished the response to KCl, reduced the response to carbachol or neurokinin A but had no effect on the response to endothelin. Bay K 8644 (1 microM) markedly potentiated the response to KCl but had little or no effect on the response produced by the other stimulants. 3. Superfusion of the strips with a nominally calcium (Ca)-free medium containing EDTA (1 mM) for 30 min markedly reduced the response to carbachol, neurokinin A and endothelin, although a small response was still evident at high concentrations. Likewise, after a prolonged (60 min) superfusion of the strips with a high K (80 mM) Ca-free medium plus EDTA (1 mM) these three agonists still produced a small contractile response. 4. The nifedipine (1 microM) resistant response to carbachol, neurokinin A or endothelin was markedly depressed by LaCl3 (1 mM). In contrast, the nifedipine-(1 microM) resistant response to carbachol was not modified by NiCl2 (0.1 mM) or omega-conotoxin (0.1 microM). 5. Caffeine produced divergent effects depending upon the temperature of incubation: a relaxation at 37 degrees C and a concentration-dependent (2.5-20 mM) contraction at 25 degrees C. The latter was markedly inhibited by procaine (3 mM) but unaffected by nifedipine (1 microM). 6. After a prolonged (60 min) superfusion with a high K, Ca-free medium containing EDTA the response to carbachol (100 microM) was abolished by previous exposure to procaine (3 mM). Conversely, the response to endothelin (1 microM) was unaffected by procaine. The response to endothelin in these experimental conditions was also resistant to LaCl3 (1 mM). 7. These findings indicate that multiple sources of Ca are mobilized for contraction of the human bladder muscle by different stimulants. Dihydropyridine- and voltage-sensitive Ca channels provide the major if not the sole source of Ca for the response to KCl, play some role in the response to muscarinic (carbachol) or NK-2 tachykinin receptor stimulation but are not involved in the response to endothelin. Carbachol, neurokinin A and endothelin all mobilize a Ca pool (either extracellular or located at membrane level) which is LaCl3-sensitive but nifedipine-resistant. Neither T- nor N-type channels appear to be involved in the response to carbachol.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
948.
Augmentation and subsequent attenuation of Ca2+ current due to lipid peroxidation of the membrane caused by t-butyl hydroperoxide in the rabbit sinoatrial node. 总被引:2,自引:1,他引:1
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N. Sato M. Nishimura H. Tanaka N. Homma Y. Watanabe 《British journal of pharmacology》1989,98(3):721-723
Cellular electrophysiological effects of membrane lipid peroxidation by t-butyl hydroperoxide (TBH) were studied in the rabbit sinoatrial (SA) node. Superfusion for 1-5 min with 300 microM TBH caused an initial increase and subsequent decrease in the spontaneous firing frequency of the SA node. Voltage clamp experiments revealed that TBH initially enhanced but later blocked the Ca2+ current. Thus, membrane lipid peroxidation appears to accelerate and then suppress physiological automaticity by causing biphasic changes in the Ca2+ current. 相似文献
949.
M. S. Bornman J. M. C. Oosthuizen H. C. Barnard G. W. Schulenburg D. Boomker and S. Reif 《Andrologia》1989,21(5):483-485
Several substances can interfere with microtubular function eg. colchicine. Melatonin, a hormone secreted by the pineal gland has similar effects as colchicine on microtubules. In this study melatonin levels were determined in both plasma and seminal plasma of patients with good or impaired motility and forward progression. There was no statistically significant difference between the mean plasma and seminal plasma values of patients with good or impaired motility and forward progression. There was no correlation between seminal plasma melatonin and impaired motility or any other semen parameter. There was also no correlation between plasma and seminal plasma concentrations of melatonin. High seminal plasma melatonin concentrations were not necessarily associated with impaired sperm motility. From these it is concluded that seminal plasma melatonin plays no important role in sperm motility. 相似文献
950.
Ocular motor and manual tracking in Parkinson''s disease and the effect of treatment. 总被引:1,自引:1,他引:0
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J M Gibson R Pimlott C Kennard 《Journal of neurology, neurosurgery, and psychiatry》1987,50(7):853-860
A quantitative analysis of unpredictable saccadic and smooth pursuit ocular motor and manual tracking was performed in 15 mildly affected, previously untreated subjects suffering from Parkinson's disease and in age-matched normal controls. The patients' ocular saccades were characterised by an increased variability of their latencies and reduced accuracy, with normal velocity profiles apart from saccadic duration. Their smooth pursuit had a decreased velocity gain. Similar abnormalities were found with manual tracking. Clinical improvement with dopaminergic drugs was associated with an improvement of saccadic accuracy and smooth pursuit gain. It is postulated that the ocular motor changes seen in Parkinson's disease are contingent upon functional dopamine levels in the basal ganglia. 相似文献