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71.
Immunologic Research - Results of the anti-nuclear antibodies-indirect immunofluorescence assay (anti-cell antibodies test) on HEp-2 cell substrates should be communicated to clinicians in a...  相似文献   
72.

We aimed to analyze the outcome and identify predictors of hospital mortality in patients with refractory cardiac arrest (CA) complicating acute coronary syndromes (ACS) and requiring veno-arterial extracorporeal membrane oxygenation (VA-ECMO) treatment. Between Jan-2005 and Dec-2019, 51 patients underwent urgent VA-ECMO implantation for CA in ACS. Patients were divided in two groups: “in-hospital” cardiac arrest (IHCA) and “out-of-hospital” cardiac arrest (OHCA). Prospectively collected data were retrospectively analyzed and compared between groups. Predictors for hospital mortality were investigated. IHCA and OHCA patients were 32 (62.7%) and 19 (37.3%), respectively. The groups differed for: male gender (72% vs 95%; p?=?0.070), lactate peak level (8.5?±?4.3vs10.7?±?2.9; p?=?0.023), total elapsed time from CA to VA-ECMO implantation in both groups (p?<?0.001) and elapsed time from CA (IHCA group) or hospital arrival (OHCA group) to VA-ECMO implantation (38 min vs 80 min; p?=?0.001). At logistic regression analysis, concomitant lactate level greater than 8.0 mmol/L and elapsed time from CA to VA-ECMO?≥?30 min were predictors of increased mortality (OR 3.9; 95% CI 1.19–12.79; p?=?0.025) for the entire population. In-hospital mortality was 60.8% (31/51 patients): 68.4% in OHCA group and 56.2% in IHCA group. No risk factors related to 30-day mortality resulted significant at univariable analysis. When rapidly instituted, VA-ECMO improves survival in patients with refractory cardiac arrest allowing coronary syndrome treatment. The association of an elapsed time from CA to VA-ECMO implantation longer than 30 min and a preoperative lactate peak level over 8.0 mmol/L predict a poor outcome, independently from being IHCA or OHCA.

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73.
Patients with cirrhosis are frequently submitted to radiological procedures that require the administration of contrast media. Contrast media is a well-known cause of renal failure, particularly in the presence of some predisposing conditions. However, it is not known whether cirrhosis constitutes a risk factor for contrast media-induced renal failure. The aim of this study was to assess the possible nephrotoxicity of contrast media in patients with cirrhosis. In a first protocol, renal function was evaluated with sensitive methods (glomerular filtration rate using iothalamate I 125 clearance and renal plasma flow using iodohippurate I 131 clearance) before and 48 hours after the administration of contrast media in 31 patients with cirrhosis (20 with ascites, 5 with renal failure). Solute-free water clearance, urine sodium, prostaglandins, and markers of tubular damage were also measured. The administration of contrast media was not associated with significant changes in renal function tests, neither in the whole group of patients nor in patients with ascites or renal failure. Urinary prostaglandin E2 and N-acetyl-beta-D-glucosaminidase increased significantly, but sodium and solute-free water excretion remained unchanged. In a second protocol, a different series of 60 patients with cirrhosis and renal failure were examined prospectively. No patient had renal failure due to contrast media. Only in 1 patient with septic shock was contrast media a possible contributing factor. In conclusion, the administration of contrast media is not associated with adverse effects on renal function in patients with cirrhosis. Cirrhosis does not appear to be a risk factor for the development of contrast media-induced nephrotoxicity.  相似文献   
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Limited proteolysis of phosphocellulose-purified tubulin with subtilisin resulted in cleavage of both alpha and beta tubulin subunits, with the formation of two major fragments (S alpha, and S beta, 48 kDa) and a small peptide (4 kDa) containing the carboxyl-terminal region of tubulin. Interestingly, tubulin cleaved under the present conditions showed an increased ability to assemble into large polymers in the absence of MAPs and under conditions that do not promote assembly of undigested tubulin--i.e., low magnesium concentrations and the absence of taxol and polyalcohols. The critical concentrations for the subtilisin-cleaved tubulin assembly was similar to that of MAPs-promoted tubulin assembly. Assembly product from subtilisin-cleaved tubulin consisted mainly of protofilament bundles, hooked polymer, and open tubules, structures showing equatorial and longitudinal spacings of 50 and 40 A, respectively. The existence of junctions between polymer walls indicates that the carboxyl-terminal removal facilitates polymer-polymer interactions. These results, together with previous studies on the involvement of the carboxyl-terminal domain of tubulin in its interaction with MAP-2, suggest a regulatory role for this domain in tubulin assembly. Thus, in general terms the tubulin molecule can be analyzed as a protein containing two essential domains with functional significance, one domain playing a major role in self-association and the other (the carboxyl-terminal moiety) playing a regulatory role in modulating the interactions responsible for self-association.  相似文献   
76.
BACKGROUND: We have observed profound deficits in hippocampal synaptic plasticity and one-trial learning in offspring whose mothers drank moderate quantities of ethanol during pregnancy. In the present study, we examined the question of whether lower maternal blood ethanol concentrations (BECs) could produce functional deficits in offspring. METHODS: Rat dams consumed either a 2%, 3%, or 5% ethanol liquid diet throughout gestation. Three other groups of dams were pair-fed a 0% ethanol liquid diet, and a seventh group consumed lab chow ad libitum. Adult offspring from each diet group were assigned either to studies of evoked [3H]-D-aspartate (D-ASP) release from hippocampal slices or spatial learning studies using the Morris Water Task. RESULTS: Consumption of the 2%, 3%, and 5% ethanol liquid diets produced mean peak maternal BECs of 7, 30 and 83 mg/dL, respectively. Consumption of these ethanol diets had no effect on offspring birthweight, litter size or neonatal mortality. Likewise, evoked D-ASP release from hippocampal slices and performance on a standard version of the Morris Water Task were not affected by prenatal ethanol exposure. By contrast, activity-dependent potentiation of evoked D-ASP release from slices and one-trial learning on a "moving platform" version of the Morris Water Task were markedly reduced in offspring whose mothers consumed the 5% ethanol liquid diet. Intermediate deficits in these two parameters were observed in offspring from the 3% ethanol diet group, whereas offspring from the 2% ethanol diet group were not statistically different than controls. CONCLUSIONS: We conclude that the threshold for eliciting subtle, yet significant learning deficits in offspring prenatally exposed to ethanol is less than 30 mg/dL. This BEC is roughly equivalent to drinking 1 to 1.5 ounces of ethanol per day.  相似文献   
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BACKGROUND: Innate inflammatory responses to endotoxin (lipopolysaccharide) contribute to the development of alcoholic liver disease (ALD). A single-nucleotide polymorphism (-159C/T) in the promoter region of the gene coding for CD14 (a lipopolysaccharide receptor) could be associated with the development of ALD. We sought too investigate the relationship between the CD14/-159C/T polymorphism and advanced ALD and acute-phase protein levels in heavy drinkers. METHODS: A total of 138 heavy drinkers consecutively admitted to an Internal Medicine department were genotyped for the CD14/-159C/T polymorphism. Serum samples were analyzed for lipopolysaccharide-binding protein (LBP), soluble CD14 (sCD14), C-reactive protein (CRP), and immunoglobulin (Ig) A, IgG, and IgM. Patients with ascites or liver encephalopathy (n = 35) were classified as having advanced ALD. RESULTS: After adjusting for potential confounding variables, the CD14/-159TT genotype was positively associated with advanced ALD (odds ratio, 2.99; 95% confidence interval, 1.09-8.24, p = 0.03) and serum LBP (p = 0.01) and sCD14 (p = 0.04) levels. The CD14/-159C/T polymorphism was not associated with serum levels of CRP, IgA, IgG, or IgM. CONCLUSIONS: Our results support the notion that CD14/-159TT homozygous heavy drinkers have higher levels of the LPS-binding acute-phase proteins (LBP and sCD14) than do carriers of the CD14/-159C allele. Also, the CD14/-159TT genotype may be a risk factor for advanced ALD.  相似文献   
80.
Klebsiella bacteremia: an analysis of 100 episodes   总被引:7,自引:0,他引:7  
During a five-year period, 204 patients had klebsiella bacteremia at this institution; these cases constituted 6.6% of the total episodes of bacteremia. The incidence was 2.3 cases per 1,000 admitted patients. A random group of 100 cases was chosen for analysis in the present study. The disease was community acquired in 23%, nosocomially acquired in 77%, unimicrobial in 88%, or part of a polymicrobial bacteremia in 12% of episodes. Three-quarters of the episodes were caused by Klebsiella pneumoniae and the remaining one-quarter, by Klebsiella oxytoca. Portals of entry, in decreasing order of frequency, were urinary, respiratory, and biliary tracts. Twenty-four percent of the Klebsiella isolates were resistant to gentamicin. The most frequent clinical finding (in 96% of the cases) was fever. Shock occurred in 22% and pyogenic metastatic foci, in 5% of the patients. None of the patients had evidence of disseminated intravascular coagulation. Overall mortality was 25%, and factors associated with poor prognosis were inadequacy of antimicrobial chemotherapy, septic shock, type of underlying disease, and clinical condition of the patients.  相似文献   
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