Validation of a measure of excessive drinking: frequency per year that BAL exceeds 0.08%

Although self-report data are generally evaluated as reliable, validity estimates for self-reported drinking behavior are not as favorable. A new method of measurement addressing problems currently associated with the questionable validity of self-report drinking information is introduced. Study 1 tests the correspondence between the new measure (occasions per year blood alcohol level exceeded 0.08%), traditional self-report measures, and laboratory alcohol consumption. The novel measure correlated most strongly with volume of alcohol consumed in the laboratory compared to the traditional measures. In Study 2 the novel measure was favored over a traditional measure when discriminating between the presence and absence of problem-drinking symptoms.     

A comparison of orocaecal transit times assessed by the breath hydrogen test and the sulphasalazine/sulphapyridine method in healthy beagle dogs

Orocaecal transit time (OCTT) was assessed in six healthy beagles by means of the breath hydrogen test (BH2T) and the sulphasalazine/sulphapyridine method (SLZ) after the administration of a test meal of canned food mixed with sulphasalazine. Orocaecal transit time was defined as the time taken from the oral administration of the test meal to the time when the first portion of the meal reached the colon. In five of the dogs the OCTTs assessed by the BH2T were shorter than those measured by the SLZ method by 30, 15, 45, 30 and 45 minutes. However, the median OCTT assessed by the BH2T (135 minutes, range 120 to 195 minutes) was not significantly different from that measured by the SLZ (180 minutes, range 150 to 210 minutes) and was highly correlated with it (r = 0.94, P = 0.016). The sixth dog maintained baseline hydrogen and plasma sulphapyridine readings throughout the monitoring period and the OCTT could not be measured.     

Studies on the time-course of ethanol''s acute effects on skeletal muscle protein synthesis: comparison with acute changes in proteolytic activity

The complexity of the spot patterns of two-dimensional electrophoresis gels made it necessary to use image processing techniques to analyze the gels. An important issue in the analysis is the detection and quantification of the protein spots. In this paper we describe a new technique to segment and model the different spots. For the segmentation of a gel into its different spot regions we apply a watershed technique, which is robust and efficient. For the quantification of the spots, a new spot model is constructed, based on diffusion principles. Besides the advantage of having a physical interpretation, the model is demonstrated to be superior to the commonly used Gaussian models.     

Hepatitis G virus infection in hemodialysis patients and the effects of interferon treatment

OBJECTIVE: To characterize the nature of hepatitis G virus (HGV) infections in hemodialysis patients and to determine the responsiveness of HGV to antiviral therapy in these patients. METHODS: HGV, a recently identified flavivirus, is associated with non-A-E viral hepatitis infections. We studied HGV infections in hepatitis C virus (HCV)-infected hemodialysis patients over a 1-yr period, using two independent PCR assays and nucleic acid sequencing. Thirty-four of 63 study patients were treated with interferon. RESULTS: We observed a 27% prevalence (17/63 patients) and a 4% annual incidence of HGV infections in the study population. HGV was not detected in any of the 10 HGV-infected patients immediately after interferon therapy. Although seven of these 10 patients developed HGV relapses, three had long-term responses. The interferon responsiveness of HGV and HCV appeared to be unrelated. In contrast, all seven untreated HGV-infected patients remained viremic. Sequence analyses of the different HGV isolates revealed only very limited genetic variability in the polymerase chain reaction-amplified regions of HGV during 1 yr of observation. CONCLUSIONS: Our data suggest that HCV-infected hemodialysis patients are at substantial risk of acquiring HGV infection and that HGV infections are prevalent in this population. In addition, HGV infections become chronic but are responsive to interferon treatment.     

Effect of a nitric oxide synthase inhibitor and a glucocorticosteroid on exhaled nitric oxide

Nitric oxide (NO) is produced by a variety of cells within the respiratory tract, including inflammatory epithelial cells. NO has been detected in the exhaled air of normal human subjects, and its concentration is raised in asthmatic patients. To study whether exhaled NO arises from the respiratory tract, we administered a NO synthase (NOS) inhibitor, NG-monomethyl-L-arginine (L-NMMA), by inhalation (490 mg) in a double-blind randomized manner in nine normal and six asthmatic subjects. Because exhaled NO may arise from an inducible isoform of NO synthase that may be inhibited by glucocorticosteroids, we also studied the effects of oral prednisolone (30 mg orally for 3 d) in seven normal and six asthmatic subjects in a separate double-blind crossover study with matched placebo. After nebulized L-NMMA, there was a significant fall in peak exhaled NO compared with saline control values, with a mean fall of 43.6 +/- 5.6% in normal subjects (p < 0.01) and of 39.7 +/- 6.5% (p < 0.01) in asthmatic subjects, which persisted for 4 h. There were no effects of L-NMMA inhalation on heart rate, blood pressure, or FEV1 in either normal or asthmatic patients. Administration of oral prednisolone (30 mg) resulted in a fall in exhaled NO concentrations in asthmatic subjects by 21.6 +/- 5.0% at 48 h (p < 0.01) but no significant change in normal subjects. These data suggest that NOS inhibitors may be safely given in normal and asthmatic patients and that the increased exhaled NO seen in asthmatic patients is likely to be caused by induction of inducible NOS.     

A dilemma in analysis: issues in the serial measurement of quality of life in patients with advanced lung cancer

Despite the availability of several instruments to evaluate quality of life (QL) over time in patients with lung cancer, barriers in measurement remain. This methodological study used LCSS data (Lung Cancer Symptom Scale, a disease- and site-specific QL measure) to examine analysis methods to quantify QL where data needed for serial evaluation may be missing. Data from two large randomized trials, conducted at 30 centers, of a new combination chemotherapy regimen incorporating a new agent for patients (n = 673) with Stage III and IV non-small cell lung cancer were obtained for this study. QL had been prospectively measured at baseline, day 29, and every six weeks thereafter using the LCSS. For the slope analysis (SA) and area under the curve (AUC) analyses, an adjustment score of zero was used to indicate QL on the day of death (mortality adjustment) and each subsequent day until the end of the assessment period. Significant differences in QL, symptom scores and known prognostic factors at baseline were found in the attrition group. SA and AUC analysis allowed inclusion of 581 patients, giving an adequacy rate of 86%. By using a mortality adjustment, an additional 45 patients were included, increasing the inclusion rate to 93%. With the use of the mortality adjustment, QL was shown to decline over the interval, as opposed to rise if the adjustment had not been performed. The conclusions of the study were: (1) analysis for serial data using SA and AUC provides useful, but differing information; (2) when attrition (caused by death) is a factor, a mortality adjustment presented a more accurate assessment of QL as an endpoint; (3) more frequent evaluations of QL will capture rapid changes in patient status and reduce the attrition bias; (4) all patients should be followed until they die; and (5) QL should be given full consideration as a primary endpoint separate from survival.