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111.
Breitmeier D Becker N Weilbach C Albrecht K Scheinichen D Panning B Schneider U Jüttner B 《Alcoholism, clinical and experimental research》2008,32(10):1708-1713
Background: Polymorphonuclear, neutrophil granulocytes (PMN) play a major role in the control of infections, and people who abuse alcohol are susceptible to infections. Resistance against infections ensues intracellularly following initial phagocytosis of microorganisms with the oxygen‐dependent respiratory burst, the key enzyme of which is the respiratory burst oxidase, whereby oxygen radicals are produced for microbial destruction. To date there is insufficient information available in connection with the process of impaired defence against infection in patients suffering from alcohol dependence. Therefore, our investigation was carried out to determine the influence of alcohol exposition on the formation of oxygen radicals and the respiratory burst. Methods: 4.5 ml of whole blood was taken from 10 healthy adults and 10 patients suffering from alcohol dependence. An additional 3.5 ml of whole blood was taken from the alcoholic patients for determination of the blood alcohol concentration. The respiratory burst of PMN was tested using the Four‐Colour‐Continuous Flow Cytometer. Each experimental procedure consisted of 4 test samples [negative controls, Escherichia coli, FMLP‐supplement (N‐formyl‐l‐methionyl‐l‐leucyl‐l‐phenylalanin), PMA‐supplement (phorbol‐12‐myristate‐13‐acetate)]. Differing concentrations of ethanol were also introduced to each of the tests performed (0.20 to 4.00 g/l). Results: Ethanol revealed a marked decrease of burst activity in those patients suffering from alcoholism with increased alcohol concentration. A dependence between the burst activity and the ethanol concentration was seen to be statistically significant. This effect was only evident after stimulation with E. coli and FMLP in those patients with alcohol dependence. Conclusion: The results presented in this study show an impairment in the function of PMN in those patients addicted to alcohol due to the decrease in burst activity. In view of the results of the different stimuli, the second‐messenger effects were not evident. A clarification of this phenomenon could well be assumed as an allosteric receptor effect on the burst oxidase, namely, a direct effect on the phagocytosis interaction between circulating granulocytes and causative organisms. 相似文献
112.
Karl Egerer Julia Hertzer Eugen Feist Anja Albrecht Paul Eberhard Rudolph Thomas Drner Gerd‐Rüdiger Burmester 《Arthritis care & research》2003,49(4):546-548
Objectives
To determine the usefulness of sE‐selectin as a marker for early diagnosis and stratification of rheumatoid arthritis.Methods
We investigated several markers of disease activity, including circulating adhesion molecules and other standard laboratory tests, in a 2–3 year followup analysis of patients with rheumatoid arthritis.Results
The mean ± SD levels of sE‐selectin (91.68 ± 31.8 ng/ml versus 49.83 ± 14.76 ng/ml) and rheumatoid factor (375.7 ± 394.4 U versus 44.66 ± 37.63 U) were strongly elevated in severe (n = 15) versus mild (n = 7) courses of disease. Statistical calculation of mean and standard deviation revealed that sE‐selectin represents a highly significant marker for the presence of persistent and aggressive disease over time, regardless of therapeutic intervention and observation time points (P = 0.0004). Notably, regression analysis identified constant values for all parameters analyzed and, therefore, a stable course of the disease could be predicted from the beginning.Conclusion
sE‐selectin appears to be a powerful marker to predict the severity of rheumatoid arthritis.113.
Poynard T McHutchison J Goodman Z Ling MH Albrecht J 《Hepatology (Baltimore, Md.)》2000,31(1):211-218
Randomized trials have shown the enhancement of efficacy with interferon alfa-2b and ribavirin (IFN-R) in comparison with interferon monotherapy (IFN) as first line treatment of chronic hepatitis C. Further definition of response based on disease, patient, and treatment characteristics is needed to determine the degree of benefit for the various patient subgroups. The aim of this study was to answer this question by analyzing the data from 1,744 naive patients included in trials that compared 24- or 48-week IFN-R treatment. Response factors were identified by logistic regression and receiver operating characteristics curves. Five independent characteristics were associated with a sustained loss of hepatitis C virus (HCV) RNA (<100 copies/mL) 24 weeks after the end of treatment: genotype 2 or 3, baseline viral load less than 3.5 million copies/mL, no or portal fibrosis, female gender, and age younger than 40 years. There was a significant advantage for IFN-R in comparison with IFN alone whatever the combination of factors. The most efficient strategy is to treat all patients for 24 weeks. If the 24-week polymerase chain reaction (PCR) is positive, treatment can be stopped. If the 24-week PCR is negative, patients with fewer than 4 favorable factors should be treated for an additional 24 weeks. Conclusion: The combination of IFN-R is better as first line treatment than IFN monotherapy. For patients who are PCR negative after 24 weeks of treatment, genotyping and baseline viral load, fibrosis stage, gender, and age are useful predictive factors in determining whether to continue an additional 24 weeks of treatment. 相似文献
114.
Wolfgang M Brueckl Berit Fritsche Brigitte Seifert Frank Boxberger Heinz Albrecht Roland S Croner Axel Wein Eckhart G Hahn 《World journal of gastroenterology : WJG》2006,12(45)
AIM: To assess the extent and reasons of noncompliance in surveillance for patients undergoing polypectomy of large (≥ 1 cm) colorectal adenomas.METHODS: Between 1995 and 2002, colorectal adenomas ≥ 1 cm were diagnosed in 210 patients and subsequently documented at the Erlangen Registry of Colorectal Polyps. One hundred and fifty-eight patients (75.2%) could be contacted by telephone and agreed to be interviewed. Additionally, records were obtained from the treating physicians.RESULTS: Fifty-four out of 158 patients (34.2%)neglected any surveillance. Reasons for non-compliance included lack of knowledge concerning surveillance intervals (45.8%), no symptoms (29.2%), fear of examination (18.8%) or old age/severe illness (6.3%).In a multivariate analysis, the factors including female gender (P = 0.036) and age ≥ 62 years (P = 0.016)proved to be significantly associated with non-compliance in surveillance.CONCLUSION: Efforts to increase compliance in surveillance are of utmost importance, This applies particularly to women's compliance. Effective strategies for avoiding metachronous colorectal adenoma and cancer should focus on both the improvement in awareness and knowledge of patients and information about physicians for surveillance. 相似文献
115.
Andrea L. Frump Marjorie Albrecht Bakhtiyor Yakubov Sandra Breuils-Bonnet Valrie Nadeau Eve Tremblay Francois Potus Junichi Omura Todd Cook Amanda Fisher Brooke Rodriguez R. Dale Brown Kurt R. Stenmark C. Dustin Rubinstein Kathy Krentz Diana M. Tabima Rongbo Li Xin Sun Naomi C. Chesler Steeve Provencher Sebastien Bonnet Tim Lahm 《The Journal of clinical investigation》2021,131(6)
Women with pulmonary arterial hypertension (PAH) exhibit better right ventricular (RV) function and survival than men; however, the underlying mechanisms are unknown. We hypothesized that 17β-estradiol (E2), through estrogen receptor α (ER-α), attenuates PAH-induced RV failure (RVF) by upregulating the procontractile and prosurvival peptide apelin via a BMPR2-dependent mechanism. We found that ER-α and apelin expression were decreased in RV homogenates from patients with RVF and from rats with maladaptive (but not adaptive) RV remodeling. RV cardiomyocyte apelin abundance increased in vivo or in vitro after treatment with E2 or ER-α agonist. Studies employing ER-α–null or ER-β–null mice, ER-α loss-of-function mutant rats, or siRNA demonstrated that ER-α is necessary for E2 to upregulate RV apelin. E2 and ER-α increased BMPR2 in pulmonary hypertension RVs and in isolated RV cardiomyocytes, associated with ER-α binding to the Bmpr2 promoter. BMPR2 is required for E2-mediated increases in apelin abundance, and both BMPR2 and apelin are necessary for E2 to exert RV-protective effects. E2 or ER-α agonist rescued monocrotaline pulmonary hypertension and restored RV apelin and BMPR2. We identified what we believe to be a novel cardioprotective E2/ER-α/BMPR2/apelin axis in the RV. Harnessing this axis may lead to novel RV-targeted therapies for PAH patients of either sex. 相似文献
116.
Jasmine Ramcharitar Veronica M. Afonso Steffen Albrecht David A. Bennett Andrea C. LeBlanc 《Neurobiology of aging》2013
Caspase-6 (Casp6), a cysteinyl protease that induces axonal degeneration, is activated early in Alzheimer Disease (AD) brains. To determine whether Casp6 activation is responsible for early cognitive impairment, we investigated the abundance of Casp6 activity, paired helical filament–1 (PHF-1) phosphorylated Tau and amyloid beta peptide (Aβ) pathology by immunohistochemistry in the hippocampal formation of aged non–cognitively impaired (NCI) individuals. Casp6 activity was restricted to the entorhinal cortex (ERC) and CA1 regions of the hippocampus. Pathology scores were then correlated with cognitive scores obtained within 1 year of death. Regression analyses revealed that ERC and CA1 Casp6 activity were the main contributor to lower episodic memory performance, whereas ERC PHF-1 pathology predicted lower semantic and working memory performance. Aβ did not correlate with any of the cognitive tests. Because Casp6 activity and PHF-1 pathology are intimately associated with AD pathology and memory decline is an early event in AD, we conclude that Casp6 activity and PHF-1 immunoreactivity in ERC identifies aged individuals at risk for developing AD. 相似文献
117.
The comparative morphology of juvenile avian skulls is poorly known. Here, we survey the shape of the squamosal (os squamosum) across juvenile skulls of avian higher-level clades. In all palaeognathous birds, the rostral end of the squamosal does not surpass the parietal and does not reach the frontal. This morphology is likely to be plesiomorphic for neornithine birds. A short squamosal also occurs in some Neognathae, but in most neognathous birds the squamosal contacts the frontal, and in some taxa the bone is strongly elongated and distinctly surpasses the parietal. Some clades show a notable variation in squamosal morphology. This is, for example, true for Strigiformes, where the taxon Athene differs from the other examined owls in squamosal size, and for the Passeriformes, where Old World Suboscines are characterized by a distinctive squamosal morphology. A unique derived squamosal morphology is for the first time reported for the Apodidae and Hemiprocnidae, in which the bone forms a elongated rostral process that runs along most of the orbital rim. In non-avian theropods, the squamosal articulates with the postorbital and delimits the upper temporal opening. Extant birds lack a postorbital, but a topological correlation between the squamosal and the postorbital process is maintained in most taxa of the Neognathae. The phylogenetic significance of squamosal morphology is diminished by the fact that closely related taxa often show very disparate shapes of the bone, and squamosal morphology appears to be determined by multiple functional constraints including skull geometry, brain morphology and, possibly, nostril type. 相似文献
118.
Linda Broer Veryan Codd Dale R Nyholt Joris Deelen Massimo Mangino Gonneke Willemsen Eva Albrecht Najaf Amin Marian Beekman Eco J C de Geus Anjali Henders Christopher P Nelson Claire J Steves Margie J Wright Anton J M de Craen Aaron Isaacs Mary Matthews Alireza Moayyeri Grant W Montgomery Ben A Oostra Jacqueline M Vink Tim D Spector P Eline Slagboom Nicholas G Martin Nilesh J Samani Cornelia M van Duijn Dorret I Boomsma 《European journal of human genetics : EJHG》2013,21(10):1163-1168
Telomere length (TL) has been associated with aging and mortality, but individual differences are also influenced by genetic factors, with previous studies reporting heritability estimates ranging from 34 to 82%. Here we investigate the heritability, mode of inheritance and the influence of parental age at birth on TL in six large, independent cohort studies with a total of 19 713 participants. The meta-analysis estimate of TL heritability was 0.70 (95% CI 0.64–0.76) and is based on a pattern of results that is highly similar for twins and other family members. We observed a stronger mother–offspring (r=0.42; P-value=3.60 × 10−61) than father–offspring correlation (r=0.33; P-value=7.01 × 10−5), and a significant positive association with paternal age at offspring birth (β=0.005; P-value=7.01 × 10−5). Interestingly, a significant and quite substantial correlation in TL between spouses (r=0.25; P-value=2.82 × 10−30) was seen, which appeared stronger in older spouse pairs (mean age ≥55 years; r=0.31; P-value=4.27 × 10−23) than in younger pairs (mean age<55 years; r=0.20; P-value=3.24 × 10−10). In summary, we find a high and very consistent heritability estimate for TL, evidence for a maternal inheritance component and a positive association with paternal age. 相似文献
119.
120.
A systematic review and meta‐analysis of perineural dexamethasone for peripheral nerve blocks
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We systematically reviewed the safety and efficacy of perineural dexamethasone as an adjunct for peripheral nerve blockade in 29 controlled trials of 1695 participants. We grouped trials by the duration of local anaesthetic action (short‐ or medium‐ vs long‐term). Dexamethasone increased the mean (95% CI) duration of analgesia by 233 (172–295) min when injected with short‐ or medium‐term action local anaesthetics and by 488 (419–557) min when injected with long‐term action local anaesthetics, p < 0.00001 for both. However, these results should be interpreted with caution due to the extreme heterogeneity of results, with I2 exceeding 90% for both analyses. Meta‐regression did not show an interaction between dose of perineural dexamethasone (4–10 mg) and duration of analgesia (r2 = 0.02, p = 0.54). There were no differences between 4 and 8 mg dexamethasone on subgroup analysis. 相似文献