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41.
Effects of reduced mucus oxygen concentration in airway Pseudomonas infections of cystic fibrosis patients 总被引:10,自引:0,他引:10 下载免费PDF全文
Worlitzsch D Tarran R Ulrich M Schwab U Cekici A Meyer KC Birrer P Bellon G Berger J Weiss T Botzenhart K Yankaskas JR Randell S Boucher RC Döring G 《The Journal of clinical investigation》2002,109(3):317-325
Current theories of CF pathogenesis predict different predisposing "local environmental" conditions and sites of bacterial infection within CF airways. Here we show that, in CF patients with established lung disease, Pseudomonas aeruginosa was located within hypoxic mucopurulent masses in airway lumens. In vitro studies revealed that CF-specific increases in epithelial O(2) consumption, linked to increased airway surface liquid (ASL) volume absorption and mucus stasis, generated steep hypoxic gradients within thickened mucus on CF epithelial surfaces prior to infection. Motile P. aeruginosa deposited on CF airway surfaces penetrated into hypoxic mucus zones and responded to this environment with increased alginate production. With P. aeruginosa growth in oxygen restricted environments, local hypoxia was exacerbated and frank anaerobiosis, as detected in vivo, resulted. These studies indicate that novel therapies for CF include removal of hypoxic mucus plaques and antibiotics effective against P. aeruginosa adapted to anaerobic environments. 相似文献
42.
A. V. Aseychev O. A. Azizova L. V. Shulenina A. P. Piryazev 《Bulletin of experimental biology and medicine》2009,147(3):312-318
The effect of oxidized fibrinogen on platelet-neutrophil complex formation was evaluated by studying the platelet aggregation
(changes in light transmission and turbidimetric assay). Activation of cells by thrombin (0.015 U/ml) in the presence of oxidized
fibrinogen was accompanied by the formation of larger intermolecular aggregates of platelets and leukocytes as compared to
those detected in experiments with non-oxidized fibrinogen. Addition of thrombin (0.2 U/ml) in the presence of oxidized fibrinogen
was followed by the formation of more stable complexes of platelets and leukocytes as compared to those revealed in experiments
with non-oxidized fibrinogen. An increase in the width of aggregation curves was most pronounced in the system of 10−4 M Fe2+ and 10−4 M H2O2 with oxidized fibrinogen. Our results indicate that oxidized fibrinogen contributes to the “floating” or suspension of platelet-leukocyte
complexes.
Translated from Byulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 147, No. 3, pp. 284–290, March, 2009 相似文献
43.
Vural C Uluoğlu O Akyürek N Oğuz A Karadeniz C 《Pathology oncology research : POR》2011,17(3):619-625
Ewing’s sarcoma family of tumors (ESFTs) are indicated by malignant, small, round and blue cell tumors of the bone and soft
tissue. Gene rearrangements between EWS gene on chromosome 22q12 and members of the ETS gene family are common in and specific
to ESFTs. Another defining characteristic of ESFTs is their membranous expression of the CD99. In contrast, such translocations
and immunoreactivity are not found in central primitive neuroectodermal tumors (cPNETs). The aim of this study was to investigate
the detection of EWS/FLI1 translocations and CD99 immunoreactivity in order to evaluate their clinicopathological features
and their roles in the differential diagnosis of these tumors. In this study, we investigated CD99 immunoreactivity using
immunohistochemistry and Ewing’s sarcoma / Friend leukaemia virus integration 1 (EWS/FLI1) translocation using the fluorescence
in situ hybridization (FISH) method in 23 cases. CD99 expression was detected in 10/11 (90%) ESFT cases and 2/7 cPNET cases.
In 18 cases EWS/FLI1 translocation was examined using the FISH method. The EWS/FLI1 translocations were detected in 7/8 (87.5%)
ESFTs cases, whereas non of 8 cPNET cases were detected with this translocation. One case could not be classified as either
central or peripheral, showed EWS/FLI1 translocation. There was a statistically significant difference in CD99 expression
(p = 0.0013) and EWS/FLI1 translocation (p = 0,002) between cPNETs and ESFTs cases. In conclusion, CD99 expression and EWS/FLI1 translocation are specific and sensitive
markers in the diagnosis of ESFTs. However, these were often not found in cases of cPNET. Therefore, in the diagnosis of ESFTs,
clinical, radiological, histopathological and immunohistochemical parameters should always be evaluated together. 相似文献
44.
Erkan D Harrison MJ Levy R Peterson M Petri M Sammaritano L Unalp-Arida A Vilela V Yazici Y Lockshin MD 《Arthritis and rheumatism》2007,56(7):2382-2391
OBJECTIVE: To determine the efficacy of a daily dose of 81 mg aspirin in primary thrombosis prevention in asymptomatic, persistently antiphospholipid antibody (aPL)-positive individuals (those with positive aPL but no vascular and/or pregnancy events). METHODS: The Antiphospholipid Antibody Acetylsalicylic Acid (APLASA) study was a multicenter, randomized, double-blind, placebo-controlled clinical trial in which asymptomatic, persistently aPL-positive individuals were randomized to receive a daily dose of 81 mg of aspirin or placebo. In a separate observational and parallel study, asymptomatic, persistently aPL-positive individuals who were taking aspirin or declined randomization were followed up prospectively. RESULTS: In the APLASA study, 98 individuals were randomized to receive aspirin or placebo (mean +/- SD followup period 2.30 +/- 0.95 years), of whom 48 received aspirin and 50 received placebo. In the observational study, 74 nonrandomized individuals were followed up prospectively (mean +/- SD followup period 2.46 +/- 0.76 years); 61 received aspirin and 13 did not. In the APLASA study, the acute thrombosis incidence rates were 2.75 per 100 patient-years for aspirin-treated subjects and 0 per 100 patient-years for the placebo-treated subjects (hazard ratio 1.04, 95% confidence interval 0.69-1.56) (P = 0.83). Similarly, in the observational study, the acute thrombosis incidence rates were 2.70 per 100 patient-years for aspirin-treated subjects and 0 per 100 patient-years for those not treated with aspirin. All but 1 patient with thrombosis in either study had concomitant thrombosis risk factors and/or systemic autoimmune disease at the time of thrombosis. CONCLUSION: Our results suggest that asymptomatic, persistently aPL-positive individuals do not benefit from low-dose aspirin for primary thrombosis prophylaxis, have a low overall annual incidence rate of acute thrombosis, and develop vascular events when additional thrombosis risk factors are present. 相似文献
45.
46.
BACKGROUND: Translocating enteric bacteria play an important role in the development of infections following partial hepatectomy. The intestine itself is the first line of defence against bacterial translocation (BT). We investigated the effect of N-acetylcysteine (NAC) on BT and the intestinal wall. METHODS: We compared four groups of Sprague-Dawley male rats (eight in each group): sham, sham plus preoperative single dose of NAC, partial hepatectomy and partial hepatectomy plus preoperative single dose of NAC. Microorganism count in the tissues and the glutathione and malondialdehyte contents of the intestinal wall were studied at the end of the 24th hour. RESULTS: Bacterial growth was observed in the spleen and mesenteric lymph nodes in the sham group. There was bacterial growth in all the samples of the partial hepatectomy group. Differences were significant except in atrial and portal blood counts. In the partial hepatectomy plus NAC treatment group, counts were significantly low in all, except atrial and portal blood samples. The malondialdehyte level in the intestinal wall was 35.38 +/- 10.27 in the sham group, increasing significantly in the partial hepatectomy group (69.50 +/- 21.48), and decreasing in the partial hepatectomy plus NAC treatment group (35.63 +/- 14.12). Glutathione levels decreased significantly in the partial hepatectomy group and increased with preoperative single-dose NAC. CONCLUSION: Partial hepatectomy resulted in oxidative disturbances in intestinal wall, which in turn gave rise to BT. Parenteral NAC protects the intestinal wall from oxidative injury and attenuates BT. 相似文献
47.
Ibrahim Hatipoglu Duygu Ercan Ceyda Acilan Aynur Basalp Deniz Durali Ahmet Tarik Baykal 《Immunobiology》2014
Hepatitis B virus (HBV) continues to be a serious worldwide health problem despite the use of protective HBV vaccines and therapeutic regimens against chronic HBV infection. Chronic HBV patients cannot induce sufficient immune responses against the virus. HBV and its antigens are believed to suppress immune responses during chronic infection. Hence, studying the role of HBV in immune suppression is very important for the development of alternative therapeutic strategies for HBV infections. 相似文献
48.
目的:了解新疆维吾尔族妇女宫颈癌与性行为的关系,为新疆维吾尔族宫颈癌的防治提供性行为干预基础。方法:对400例新疆维吾尔族宫颈癌妇女进行有关性行为的调查。结果:本组患者社会地位普遍较低,月经期及性卫生不良普遍存在,月经期用布者占58.0%,用卫生纸者只占32.0%,排便后用土块的患者占29.5%,用纸者占49.3%(包括卫生纸、旧书及报纸等),性生活前清洗外阴者为19.0%,性生活后洗外阴者为81.3%,性生活后手插入阴道清洗阴道者占80.5%;丈夫有外遇者为35.8%,自己有外遇者为12.3%;20岁及以前结婚者达到90%;平均怀孕6.2次,平均分娩5.05次,70.0%的患者20岁以前完成初娩;避孕基本上用宫内节育器(40.5%)及绝育(39.5%),用安全套的患者不到5.0%。结论:维吾尔族宫颈癌妇女中社会地位低下,性卫生及月经期卫生不良,早婚、多婚、多育,尤其是男性性混乱等宫颈癌的高危因素均普遍地存在。因此,作者认为,提高维吾尔族妇女的文化素质,开展健康教育,在维吾尔族宫颈癌的防治工作中,进行有关性行为的性健康教育干预极为迫切。 相似文献
49.
Pinarli FG Oğuz A Karadeniz C Uluoğlu O Akyürek N 《Pediatric hematology and oncology》2004,21(6):543-548
Retinoblastoma is the primary ocular malignancy affecting children under 6 years of age. The development of second malignant tumors in survivors of hereditary retinoblastoma is a well-known clinical entity and a major cause of morbidity and mortality. Rhabdomyosarcomas as second primary tumors have been only rarely described. The authors report a patient with bilateral retinoblastoma who developed a myogenic sarcoma of the orbit after 5.5 years of diagnosis. The short latency period may be explained by tumor histology with the contribution of radiotherapy and chemotherapy. The prognosis of second tumors is poor despite aggressive treatment. 相似文献
50.
Pain originating from intramuscular (IM) injection should not be underestimated, because a painful injection might incite severe fear of injection, which may lead a patient to delay seeking medical help. The aim of this study was to determine the impact of two different IM methylprednisolone injection speeds on pain intensity and pain duration. A one-group quasiexperimental design was used to study 10-second versus 30-second injection durations. According to the formula for one sample using average values, 25 patients were recruited from a dermatology clinic. Data were collected using the “Patient Characteristics Form” and the visual analog scale (VAS). The mean difference in pain levels according to the VAS in the postinjection period was significantly higher with administration of IM methylprednisolone in 10 seconds compared with 30-second administration (VAS 1.9 vs. 1.3; p < .05). The severity of pain peaked at 0 minutes for both injection speeds, but the duration of pain was longer with 10-second injections. The data showed that at multiple time points after 10-second injections, men and patients >40 years old experienced greater pain severity. Pain severity after 30-second injections was greater for patients of normal or low weight who had completed higher levels of education. In conclusion, slow IM injection of steroids improves pain management. 相似文献