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81.
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New abnormalities in the morphology, cell surface receptors, and electrolyte metabolism of In(Lu) erythrocytes 总被引:1,自引:0,他引:1
The In(Lu) phenotype is inherited as an autosomal dominant trait and is characterized by suppression of the Lutheran, P1, i, and Aua erythrocyte blood group antigens. We have developed a monoclonal antibody (L21) that strongly agglutinates all erythrocytes except In(Lu), and we have identified eight In(Lu) individuals among 42,000 blood donors tested. Studies of two families confirmed the dominant mode of inheritance and revealed several new features of this phenotype. The erythrocytes of all five affected individuals from the two families exhibited diminished hemagglutination by the lectin concanavalin A, although they reacted normally with several other lectins. The erythrocytes of two affected individuals in one family exhibited marked acanthocytosis. The erythrocytes of the proposita of the other family exhibited a mild degree of poikilocytosis, but the cells of the other two affected individuals in this family had normal morphology. The osmotic fragility of fresh In(Lu) erythrocytes was normal, but after incubation for 24 hours at 37 degrees C in plasma the In(Lu) cells exhibited a marked increase in resistance to osmotic lysis. During the incubation period the erythrocytes lost K+ and their total cation content was diminished. These data indicate that in addition to the suppression of blood group antigens noted previously, the In(Lu) phenotype includes a variety of morphological abnormalities and a defect in electrolyte metabolism. The use of L21 and similar monoclonal antibodies provides a more sensitive means of detecting In(Lu) erythrocytes than typing with human anti-Lub antisera. 相似文献
83.
Adrian Sousa Maria Teresa Pérez-Rodríguez Andrés Nodar Lucía Martínez-Lamas Francisco Jose Vasallo Maximiliano Álvarez-Fernández Manuel Crespo 《Enfermedades infecciosas y microbiología clínica》2018,36(5):284-289
Introduction
Invasive pneumococcal disease (IPD) typically presents as bacterial pneumonia, meningitis or primary bacteraemia. However, Streptococcus pneumoniae can produce infection at any level of the body (endocarditis, arthritis, spontaneous bacterial peritonitis, etc.), which is also known as unusual IPD (uIPD). There are very limited data available about the clinical and microbiological profile of these uncommon manifestations of pneumococcal disease. Our aim was to analyse clinical forms, microbiological profile, epidemiology and prognosis of a cohort of patients with unusual invasive pneumococcal disease (uIPD).Methods
We present a retrospective study of 389 patients (all adult and paediatric patients diagnosed during the period) diagnosed with IPD at our hospital (Complejo Hospitalario Universitario de Vigo) between 1992 and 2014. We performed an analysis of clinical, microbiological and demographical characteristics of patients comparing the pre-pneumococcal conjugate vaccine (PCV) period with the post-vaccination phase. IPD and uIPD were defined as follows; IPD: infection confirmed by the isolation of S. pneumoniae from a normally sterile site, which classically presented as bacterial pneumonia, meningitis or primary bacteraemia; uIPD: any case of IPD excluding pneumonia, meningitis, otitis media, rhinosinusitis or primary bacteraemia.Results
A total of 22 patients (6%) met the criteria of uIPD. A Charlson index >2 was more prevalent in uIPD patients than IPD patients (45% vs 24%; p = 0.08). The most common clinical presentation of uIPD was osteoarticular infection (8 patients, 36%), followed by gastrointestinal disease (4 patients, 18%). Infection with serotypes included in PCV-13 was significantly higher in IPD patients (65%) than in patients with uIPD, 35% (p = 0.018). Conversely, infection with multidrug-resistant strains was higher among patient with uIPD (27% vs 9%; p = 0.014). The all-cause mortality rate was 15%, 13% in the IPD group and 32% among patients with uIPD (p = 0.07). According to the multivariate analysis, a Charlson Index >2 (OR 5.1, 95% CI, 1.8–14.0) and a Pitt Score >2 (OR 1.4, 95% CI, 1.2–1.9) were independent predictors of mortality.Conclusion
uIPD is a rare entity that affects patients with more comorbidities than typical IPD and it is usually caused by non-vaccine serotypes with greater antimicrobial resistance. 相似文献84.
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86.
Yang Zhu BM Xiaohong Liu MM Xin Wei MM Baisong Wang PhD Jiuchang Zhong MD Yi Fu MD 《Journal of clinical hypertension (Greenwich, Conn.)》2014,16(9):652-657
To study the relationship between nocturnal blood pressure (BP) variation and spontaneous intracerebral hemorrhage (ICH) among Chinese hypertensive patients and its clinical significance, the authors retrospectively screened 371 patients with primary hypertension (189 patients with ICH, 182 patients without ICH) in Shanghai and analyzed their demographics, clinical information, nocturnal blood pressure variability and medication. Compared with the control group, the levels of blood glucose, triglycerides, and creatinine were significantly increased in the ICH group, along with a marked reduction in nocturnal BP drop (P<.05). Multivariate logistic regression indicated that blood glucose, creatinine, and nocturnal mean arterial pressure were risk factors for ICH, and the magnitude of nocturnal BP drop was negatively related to the risk for ICH. There was no significant difference in the prevalence of reverse dippers between the large hematoma volume group and the small hematoma volume group (χ2=2.529, P=.112), nor among the patients taking angiotensin‐converting enzyme inhibitors, angiotensin receptor blockers, or calcium channel blockers (χ2=1.981, P=.371). Reverse dipping is associated with the risk for ICH, suggesting that appropriate antihypertensive drug and chronotherapy might be effective to normalize the rhythm of abnormal circadian variation in hypertensive patients. 相似文献
87.
Junxia Zhang MD Yuping Zhang MM Wuquan Deng MM Bing Chen MD PhD 《Journal of clinical hypertension (Greenwich, Conn.)》2014,16(8):569-574
This study investigated the correlation between elevated serum uric acid (SUA) and angiotensinogen in obesity patients with hypertension. A total of 162 obese and 162 nonobese men with hypertension were recruited in this study. Plasma angiotensinogen levels were measured by enzyme‐linked immunosorbent assay. Fasting insulin (FINS) was evaluated by radioimmunoassay. Compared with nonobese patients, obese patients exhibited higher levels of angiotensinogen, FINS, and homeostasis model assessment index‐insulin resistance (HOMA‐IR) (P<.001 for all). Moreover, these indexes significantly increased in obese patients in the highest tertile of SUA when compared with those in the lowest tertile of SUA (P<.001, P=.002, P=.007, respectively). In the obese group, SUA levels were significantly related to angiotensinogen, FINS, and HOMA‐IR, respectively. Furthermore, it was demonstrated that obesity × uric acid was an independent contributor to angiotensinogen (β=0.257, P<.001). In conclusion, elevated SUA is strongly related to angiotensinogen in an obesity‐dependent manner in hypertension. 相似文献
88.
Ling Wu MM Song‐Bai Deng MM Qiang She MD 《Journal of clinical hypertension (Greenwich, Conn.)》2014,16(11):838-845
To explore the clinical effects of a calcium channel blocker compared with an angiotensin II receptor blocker in hypertensive patients, the authors collected data from randomized controlled trials. The pooled outcomes were all‐cause mortality, stroke, myocardial infarction, and heart failure. Eight head‐to‐head trials enrolling 25,084 patients were included. There was no significant mortality difference in the two arms (relative risk, 0.99; 95% confidence interval, 0.91–1.07). However, calcium channel blockers were more effective in reducing stroke (relative risk, 0.87; 95% confidence interval, 0.76–0.99) and myocardial infarction incidence (relative risk, 0.86; 95% confidence interval, 0.76–0.98). There was no significant difference with heart failure incidence between the two arms but a lower trend in patients with angiotensin II receptor blockers was noted (relative risk, 1.4; 95% confidence interval, 0.99–1.98). The meta‐analysis suggested that initially use of a calcium channel blocker might be superior to an angiotensin II receptor blocker for prevention of stroke and myocardial infarction. 相似文献
89.
Vicente Colomer-Romero Dante Rogiest Juan Antonio García-Manrique Jose Enrique Crespo 《Materials》2020,13(24)
Bio- and green composites are mainly used in non-structural automotive elements like interior panels and vehicle underpanels. Currently, the use of biocomposites as a worthy alternative to glass fibre-reinforced plastics (GFRPs) in structural applications still needs to be fully evaluated. In the current study, the development of a suited biocomposites started with a thorough review of the available raw materials, including both reinforcement fibres and matrix materials. Based on its specific properties, hemp appeared to be a very suitable fibre. A similar analysis was conducted for the commercially available biobased matrix materials. Greenpoxy 55 (with a biocontent of 55%) and Super Sap 100 (with a biocontent of 37%) were selected and compared with a standard epoxy resin. Tensile and three-point bending tests were conducted to characterise the hemp-based biocomposite. 相似文献
90.