In vivo characterization of cytotoxic intracellular edema by multicomponent analysis of transverse magnetization decay curves

The precise measurement of low numbers of leukocyte below 0.1 WBC/microliter in filtered red cell or platelet suspensions meet both aims: to check the compliance with previously determined requirements and to evaluate the performances of novel filtering material (5 log depletion or more), justified by more and more important clinical use. The reliability of results, obtained with the chosen method, is ensured by applying of validation protocol, including training of technologist, assessment of the analytical range and the detection limit, assessment of precision and accuracy. The flow cytometry (FC) and Nageotte Chamber (NC) method are the both techniques which are currently used in routine Quality Control (QC) and validated by multicenter studies. Recent developments are made for increasing the sensibility of these counting methods, thanks to higher concentration or volume of the sample to be analysed. Among the experimental techniques, requiring more advances before implementing in QC program, quantitative PCR must become essential as reference method for evaluating the efficiency of filtration, in the future.     

Comparison of the active-site conformations of bovine alpha-thrombin and meizothrombin(desF1) by electron spin resonance

The annual time-series analysis examines the impact of changes in per capita alcohol consumption (NIAAA,AEDS) on changes in community hospital admission rates (AHA) in the United States from 1950 to 1992 (n = 43). Increases in per capita alcohol consumption were expected to increase hospital admission rates contemporaneously and several years thereafter following an exponential risk function. Distributed lag models based on differenced data controlling for changes in: (1) per capita cigarette consumption; (2) private hospital insurance coverage; (3) the drinking age population; (4) per capita disposable personal income; and (5) health care regulatory interventions show a contemporaneous effect of per capita alcohol consumption on hospital admission rates. The time-series analyses imply that between 22-26% of US community hospital admissions are alcohol related. A comparable analysis indicates that per capita alcohol and tobacco expenditures contribute to approximately 28% of US community hospital admissions. The absence of statistically significant lagged effects is inconsistent with an exponentially declining risk functions. However, the contemporaneous effects of per capita alcohol and tobacco consumption suggest that a reduction in smoking and drinking will produce quick reductions in morbidity and hospitalizations.     

Contact areas in the thumb carpometacarpal joint

The thumb carpometacarpal joint is a common site of osteoarthritis. It has been hypothesized that peaks of localized stress on the dorsoradial or volar-ulnar regions, or both, of the articular surfaces of the trapezium and metacarpal lead to erosion of cartilage and may be responsible for the progression of the disease. The objective of this study was to determine the contact areas in this joint under the functional position of lateral (key) pinch and in the extremes of range of motion of the joint. These contact areas were assessed relative to the observed sites of cartilage thinning. Eight hands from cadavers of women and five from cadavers of men were tested in vitro with the thumb under a 25 N load in the lateral pinch position, and under small muscle loads (0-5 N) with the thumb in flexion, extension, abduction, adduction, and neutral positions. Contact areas of articular surfaces of the thumb carpometacarpal joint were determined for these positions using a stereophotogrammetric technique. The lateral pinch position produced contact areas predominantly on the central, volar, and volar-ulnar regions of the trapezium and the metacarpal. In three specimens, contact areas were distinctly separated between the dorsoradial and volar-ulnar regions, and in one specimen, from a man, contact occurred exclusively on the dorsoradial region of the trapezium. Using stereophotogrammetry, maps of cartilage thickness also were determined for a subset of nine specimens. The volar-ulnar, ulnar, and dorsoradial regions of the trapezium were the most common sites of thin cartilage, and these may be sites of cartilage wear.(ABSTRACT TRUNCATED AT 250 WORDS)     

Association between cigarette smoking and lipid peroxidation in a controlled feeding study

BACKGROUND: Cigarette smoke may promote atherogenesis by producing oxygen-derived free radicals that damage lipids. However, evidence in support of this hypothesis is inconsistent because most studies did not control for aspects of diet (antioxidants and lipid substrate) that may confound the association between smoking and measures of lipid peroxidation. METHODS AND RESULTS: The relationships between cigarette smoking and two measures of lipid peroxidation, breath ethane (an in vivo assay) and thiobarbituric acid-reactive substances (TBARS, an in vitro assay), were examined in 123 adults (11% of whom were smokers) participating in a controlled feeding study. After 3 weeks of controlled feeding on a common diet (36% total fat, 14% saturated fats, 6% polyunsaturated fats, and 12% monounsaturated fats), breath and fasting serum samples were collected for measurement of ethane and TBARS, respectively. Baseline characteristics of smokers and nonsmokers were similar, including several indices related to diet and nutritional status (albumin, cholesterol, body mass index, and oxygen radical-absorbing capacity). Cigarette smokers had significantly higher breath ethane (8.88 versus 1.71 pmol/L; P<.0001) and TBARS (24.0 versus 20.7 micromol/mL; P=.008) than nonsmokers. The interval between breath collection and the time the last cigarette was smoked was significantly and inversely correlated with breath ethane. Neither measure of lipid peroxidation was associated with measures of serum cholesterol or albumin, body mass index, or serum oxygen radical-absorbing capacity. CONCLUSIONS: Cigarette smokers have higher rates of in vivo and in vitro lipid peroxidation. These results support the hypothesis that the atherogenic effects of smoking are mediated in part by free radical damage to lipids.     

Effects of ketotifen on human lymphocytes in vitro and in vivo

The effects of the antiasthmatic drug ketotifen (CAS 34580-13-7) on human mononuclear leukocytes were studied in vitro and in vivo. In vitro ketotifen concentration-dependently inhibited mitogen-stimulated lymphocyte proliferation. High ketotifen concentrations also inhibited T-lymphocyte mitogen- and adenosine triphosphate stimulated increases in intracellular Ca2+ in lymphocytes and the U937 human monocyte precursor cell line, respectively; this involved inhibition of both Ca2+ influx and intracellular mobilization. In in vivo experiments, treatment of healthy volunteers with 1 mg ketotifen b.i.d. for 7 d did not alter the number or subset composition of circulating lymphocytes. Moreover, the mitogen-stimulated in vitro proliferation of lymphocytes obtained before and after ketotifen treatment in vivo was similar. It is concluded that high ketotifen concentrations can inhibit the activation of resting lymphocytes in vitro but standard ketotifen treatment does not notably affect the number of function of circulating lymphocytes in vivo.     

The prognostic significance of deletion of the long arm of chromosome 20 in myeloid disorders

OBJECTIVE: The effect of cigarette smoking on gallbladder (GB) emptying and refilling after a fatty meal was examined in 10 healthy volunteers (four women and six men, mean age 27.6 yr). METHODS: On three different days, the subjects underwent in randomized order: a control test without smoking (C), or they smoked two cigarettes during the early (0-20 min; S0-20), or late (20-40 min; S20-40) phase of the meal-induced GB emptying. GB volumes were measured ultrasonographically before the meal and at 10, 20, 30, 40, 60, 90, 120, 150, and 180 min postprandially. Two-way ANOVA was applied for statistical assessment of the results. RESULTS: The fasted GB volumes amounted to 15.7 +/- 1.8 cm3 (C), 15.0 +/- 1.7 cm3 (S0-20), and 18.4 +/- 2.3 cm3 (S20-40), F2;18 = 1.524, NS. Maximum GB emptying was observed until 60 min after the meal, with a nadir of the GB volume amounting to 7.3 +/- 1.3 cm3 (C), 6.6 +/- 1.2 cm3 (S0-20), and 7.1 +/- 1.1 cm3 (S20-40). No significant difference was found between the stimuli tested when absolute GB volumes were considered: F2;180 = 2.725, NS. Analysis of the GB emptying-refilling curves normalized for the fasted GB volume revealed that a significant inhibitory effect was produced by smoking two cigarettes during the late phase of GB emptying on the subsequent GB refilling: F2;162 = 11.066, p < 0.001 for the whole curve, and F2;72 = 7.126, p < 0.005 for the refilling phase. A significant contrast was found next between S20-40 and the control day (p < 0.001 whole curve; p < 0.005 refilling phase only), as well as between S20-40 and S0-20 (p < 0.001 whole curve; p < 0.025 refilling phase only). CONCLUSION: We conclude that smoking two cigarettes does not disturb the fatty meal-induced GB contraction in healthy humans. Subsequent GB refilling is delayed if smoking takes place during the late phase of the postprandial GB contraction.     

Plasma viral RNA load predicts disease progression in accelerated feline immunodeficiency virus infection

Viral RNA load has been shown to indicate disease stage and predict the rapidity of disease progression in human immunodeficiency virus type 1 (HIV-1)-infected individuals. We had previously demonstrated that feline immunodeficiency virus (FIV) RNA levels in plasma correlate with disease stage in infected cats. Here we expand upon those observations by demonstrating that plasma virus load is 1 to 2 logs higher in cats with rapidly progressive FIV disease than in long-term survivors. Differences in plasma FIV RNA levels are evident by 1 to 2 weeks after infection and are consistent throughout infection. We also evaluated humoral immune responses in FIV-infected cats for correlation with survival times. Total anti-FIV antibody titers did not differ between cats with rapidly progressive FIV disease and long-term survivors. These findings indicate that virus replication plays an important role in FIV disease progression, as it does in HIV-1 disease progression. The parallels in virus loads and disease progressions between HIV-1 and FIV support the idea that the accelerated disease model is well suited for the study of therapeutic agents directed at reducing lentiviral replication.