A comprehensive analysis of complex traits in problem 2A

Helicobacter pylori infection is mainly acquired in childhood, and studies on the epidemiology of this infection depend on the availability of a noninvasive diagnostic test for use in children. The aim of this study was to determine whether the carbon 13-labeled urea breath test (UBT) can be used in children by evaluating: (1) its sensitivity and specificity compared with either culture or both rapid urease test and histologic examination, (2) whether a test meal or a prolonged fast is required, (3) the usefulness after treatment for H. pylori. Eighty-eight children (mean age, 10.6 +/- 4.19 years) who were undergoing upper endoscopy were studied while fasting, not fasting, and after treatment. Children were given 50 mg of 13C-urea if they weighed less than 50 kg or 75 mg of 13C-urea if they weighed more than 50 kg with 50 mg of a glucose polymer solution in 7.5 ml of water. Breath samples were collected at baseline and at 15, 30, 45, and 60 minutes. In 63 fasting children the UBT was 100% sensitive and 97.6% specific at 30 minutes with a cutoff value of 3.5 delta 13CO2 per mil. Nonfasting tests in 23 children, performed between 1 and 2 hours after their usual meal, were 100% sensitive and 91.6% specific. In 13 children fed directly before the UBT, the sensitivity of the test was reduced to 50%. Thirty minutes was the optimal sampling time. There was a significant decrease in specificity when samples were obtained at 15 minutes, possibly caused by the interference of oral urease-producing organisms. The test was 100% sensitive and specific in 20 children after treatment for H. pylori infection. The UBT is a highly sensitive and specific test for the diagnosis of H. pylori infection in children. Neither a prolonged fast nor a test meal is required.     

SCAN test-retest reliability for first- and third-grade children

The SCAN is a popular screening test that was developed to provide a rapidly administered, standardized method for determining the potential of central auditory processing disorder (CAPD) in children between the ages of 3 and 11 years. It can be administered in 20 minutes with a portable stereo cassette player and contains three subtests: filtered words (FW), auditory figure ground (AFG), and competing words (CW). Published SCAN test-retest reliability data (Keith, 1986) used a 6-month retest interval and indicated that SCAN scores may be unreliable. No additional reliability data are available, and studies indicate that SCAN has been used by both researchers and clinicians despite reliability concerns. This investigation examined the stability of SCAN outcomes for 25 first-grade and 22 third-grade children (ages 6 to 9 years) using a 6- to 7-week retest interval. Time of day and examiner were held constant, and participants were normal-hearing, were Caucasian, and spoke English as their primary language. ANOVA outcomes indicated that both raw and standard scores improved significantly from Test 1 to Test 2 for two of the three SCAN subtests (FW and CW) and for the composite (COMP) score. Additionally, COMP-percentile-rank and age-equivalent outcomes demonstrated significant improvement from test to retest for both grades. The AFG subtest was the only SCAN measure for which a significant test-retest difference did not emerge. The highest test-retest correlation values (r) were moderately strong (0.70 < or = r < or = 0.78) and occurred for the CW and COMP scores. Implications of correlations and factor analyses are discussed. It is suggested that examiners base recommendations for additional testing, follow up, and remediation on the COMP score only. Further, it appears that second administration of the SCAN can provide a better estimate of an individual child's best performance, but lack of second-score norms confounds simple interpretation of such scores.     

Utility of biological markers during outpatient treatment of alcohol-dependent subjects: carbohydrate-deficient transferrin responds to moderate changes in alcohol consumption

A group of 25 alcohol-dependent subjects in outpatient treatment were monitored for a period of 4 weeks. They were weekly interviewed for their alcohol consumption and their serum levels of carbohydrate-deficient transferrin (CDT) and gamma-glutamyltransferase (GT) were analyzed. The majority of the patients reported an excessive and fairly constant alcohol intake during the observation period. When selecting those patients that reported periods of 1 or 2 weeks with moderate changes in alcohol consumption, corresponding changes in CDT were demonstrated. Thus, of 14 patients reporting an increased alcohol consumption for 2 weeks (mean values increased from 57 to 101 g/day), 11 showed an increase in CDT at the end of the period. The mean CDT value of all 14 increased from 5.5 to 6.7% (p < 0.05). Slight, but not significant, increases were noted in GT, indicating that CDT is more sensitive than GT in detecting increased alcohol consumption. Furthermore, of 17 patients that reported decreased alcohol consumption for one or several weeks, 14 showed decreased CDT and GT values. The mean values of all 17 were reduced from 5.1% to 4.5% (CDT) and from 126 units/liter to 97 units/liter (GT) (p < 0.05 for both parameters). The results indicate that CDT responds to moderate changes in alcohol consumption in alcohol-dependent patients and may thus be useful as a corrective tool to self-reports of alcohol consumption during outpatient treatments.     

Measurement of antecedents to drug and alcohol use: psychometric properties of the Inventory of Drug-Taking Situations (IDTS)

The development, factor structure, and validity of the Inventory of Drug-Taking Situations (IDTS) is described. This 50-item self-report questionnaire, which is an extension of the Inventory of Drinking Situations (Annis, 1982. Inventory of drinking situations; Annis, Graham & Davis, 1987, Inventory of drinking situations (IDS): User's guide), is designed to assess the situational antecedents to use of a wide range of drugs of abuse. The IDTS consists of 8 subscales that measure a client's substance use in the 8 situations identified in the work of Marlatt (1978, Alcoholism: New directions in behavioral research and treatment): Unpleasant Emotions, Physical Discomfort, Pleasant Emotions, Testing Personal Control, Urges and Temptations to Use, Conflict with Others, Social Pressure to Use, and Pleasant Times with Others. Reliability, factor structure and validity of the IDTS were assessed on 699 clients admitted to the Addiction Research Foundation's treatment facility in Toronto. The IDTS was shown to have reliable subscales. The IDTS total score correlated with self-ratings of the severity of the clients' substance use problem, and with retrospective reports of frequency of use (drugs) and quantity of use (alcohol), years of usage, and severity of dependence. Confirmatory factor analysis was used to test the fit of the data to Marlatt's model of substance use situations, as well as to several alternative models. The goodness-of-fit indicators suggested that the best fit for the data was an 8-factor model corresponding to the 8 subscales based on the Marlatt categories. Evidence was presented that the 8 subscales can be further grouped into 3 second-order factors: (1) negative situations, (2) positive situations, and (3) temptation situations. The negative situation subscales of Unpleasant Emotions, Conflict with Others and Physical Discomfort were found to be correlated with the SCL-90R Depression scale. Interpersonal Sensitivity scale and Somatization scale respectively. The positive social situation subscales of Pleasant Times with Others and Social Pressure to Use were found to be negatively correlated with percentage of time using alone, and positively correlated with pressure from friends and family to use. On the States of Change Readiness and Treatment Eagerness Scales (SOCRATES), clients at the precontemplation stage of change had relatively flat, undifferentiated IDTS profiles (i.e. little scatter of subscale scores), whereas clients in the determination stage had the most differentiation in their IDTS subscale scores. Excellent comparability was found for alcohol clients between the IDS and the IDTS. Evidence was also presented for adequate comparability between the computer and paper and pencil administrative formats of the IDTS.     

Lipopolysaccharide activation of murine splenocytes and splenic B cells increased the expression of aryl hydrocarbon receptor and aryl hydrocarbon receptor nuclear translocator

BACKGROUND: To achieve complete myocardial revascularization in patients with diffuse coronary artery disease and patients at high risk if they undergo cardiopulmonary bypass such as severe systemic disease or diffuse arteriosclerosis of the aorta, we have adopted the technique of combining direct coronary artery bypass grafting without cardiopulmonary bypass with transmyocardial laser revascularization. METHODS: From April 1995 to September 1997 this technique was used in 77 patients. Ages ranged from 37 to 85 years with a mean of 56 +/- 17 years. Diffuse coronary artery lesions were present in 46 patients, 10 had severely deranged renal function, 7 had diffuse carotid artery lesions, and 7 had aortic arch atheromas. Liver dysfunction was present in 4 patients and severe obstructive airway disease in 3. The mean left ventricular ejection fraction was 0.45 +/- 0.05. Midsternotomy approach was used in 65 patients and anterior minithoracotomy in 12. Direct coronary artery bypass grafting without cardiopulmonary bypass was done to the left anterior descending coronary artery or right coronary artery or both. Transmyocardial laser revascularization using a 1,000-W CO2 laser machine was performed on the areas supplied by ungraftable coronary arteries or even in graftable distal targets in the posterolateral or inferior wall in patients who were at high risk if they underwent cardiopulmonary bypass. RESULTS: The mean number of vessels bypassed was 1.12. One patient died of intractable ventricular arrhythmia in the early postoperative phase. Mean follow-up was 16.6 months. At 12 months 89% of the patients were angina free. Metabolic stress test demonstrated an average increase in exercise tolerance from 5.2 at baseline to 9.7 minutes at 12 months. Myocardial thallium scanning done at 3-, 6-, and 12-month intervals postoperatively revealed that myocardial perfusion in grafted segments had an exponential trend of improvement, and perfusion in transmyocardial laser revascularization segments showed a linear trend in the same period with a total gain of 28.4%. CONCLUSIONS: Transmyocardial laser revascularization is an excellent adjunct to minimally invasive coronary artery bypass grafting to achieve complete myocardial revascularization in patients with graftable vessels in the anterior wall and ungraftable vessels in the posterior and inferior wall. This achieves complete myocardial revascularization without compromising safety in patients who are at high risk if they undergo cardiopulmonary bypass. Minimal morbidity and mortality in the present series revealed that this procedure is safe, and postoperative follow-up of these patients showed significant functional improvement as well as an improvement in myocardial perfusion scan.     

Mechanism of anticholinesterase action of cation-containing organophosphorus inhibitors

An immunohistochemistry method using formalin-fixed tissues, a direct immunofluorescence method using cryostat sections, an enzyme-linked immunosorbent assay (ELISA), and a PCR method were compared for diagnosis in a litter of weaned pigs that had been experimentally inoculated with wild-type porcine epidemic diarrhea virus (PEDV) and killed between 6 and 60 h after onset of diarrhea. The immunohistochemistry method proved to be as reliable as direct immunofluorescence for diagnosis of PEDV in tissues collected postmortem. The good reliability of ELISA for investigating clinical samples was confirmed, whereas the PCR method used was ineffective.     

Immunohistochemical analysis of intratumoral heterogeneity of [131I]cG250 antibody uptake in primary renal cell carcinomas

In previous studies, highly heterogeneous uptake of 131I-labelled chimeric monoclonal antibody G250 ([131I]cG250) in primary renal cell carcinomas has been observed (intratumoral differences > factor 100). In this study, we investigated a possible correlation between intratumoral antibody uptake and four immunohistochemically determined parameters: G250 antigen expression, blood vessel density, neovascularization and percentage of viable tumour cells. Whole tumour slices of four different tumours were cut into 1-cm3 cubes, and in each cube the [131I]cG250 uptake was determined. The correlation between [131I]cG250 uptake and each individual parameter was determined in a multiple regression analysis. Additionally, the data were reanalysed after introducing arbitrary cut-off values for each parameter. If a sample showed expression of a parameter above the introduced threshold value, this sample fulfilled one condition. Subsequently, the Pearson correlation coefficients were calculated from [131I]cG250 uptake and the number of fulfilled conditions (0-3). All tumour samples with high [131I]cG250 uptake [> 0.1% of the injected dose per gram (ID g(-1))] showed high antigen expression (> 50%). However, not all samples with high antigen expression displayed high uptake. A statistically significant correlation between [131I]cG250 uptake and antigen expression was found (beta = 0.44, 0.69 and 0.74) in three out of four tumours analysed. Of the other determined parameters, no consistent correlation with [131I]cG250 uptake was found; only the percentage of viable tumour cells correlated significantly in two out of four tumours (beta = 0.80 and 0.26). Calculation of the Pearson correlation coefficients showed a statistically significant correlation between [131I]cG250 uptake and an increased number of fulfilled conditions in all tumours, indicating that each of the individual parameters contribute to the uptake of [131I]cG250. These observations indicate that high antigen expression is a prerequisite for high antibody uptake. However, regional differences in antibody uptake within a tumour cannot be explained by antigen expression alone.     

Anterior opercular syndrome, caused by herpes simplex encephalitis

Bilateral frontal and parietal opercular lesions cause a syndrome characterized by paralysis of the masticatory, facial, pharyngeal, and tongue muscles (the anterior opercular syndrome). The anterior opercular syndrome can occur in patients with herpes simplex encephalitis (HSE), but in most of these patients the diagnosis of HSE was not confirmed. We describe the anterior opercular syndrome in four patients with HSE. In two of these patients, the anterior opercular syndrome dominated the clinical picture, but in the other two patients it was overshadowed by other manifestations of HSE. The diagnosis of HSE was confirmed by detection of herpes simplex virus (HSV) DNA in the CSF (two patients), culture of the HSV from a brain biopsy (one patient), and elevated HSV antibody titers in the CSF (one patient). Our patients made a partial recovery. Acute onset of weakness of masticatory, facial, pharyngeal, and glossal muscles, accompanied by fever, headache, and partial motor seizures of the face should suggest HSE.