Chronic hepatitis C in patients with persistently normal alanine transaminase levels.

BACKGROUND & AIMS: Many patients with chronic hepatitis C virus (HCV) have persistently normal serum alanine transaminase (ALT) levels. We compared characteristics of chronic hepatitis C patients with patients with normal and elevated ALT levels using data from 3 randomized phase III trials of peginterferon alfa-2a (40 kDa). METHODS: The characteristics of 480 patients with normal ALT values (on >or=3 occasions without any increases in ALT level over a 6- to 18-month period) and 1993 patients with elevated ALT levels were compared. Sixty-eight of the 480 patients with normal ALT levels were randomized to no treatment and monitored for 72 weeks. RESULTS: More patients with normal ALT levels than patients with elevated ALT levels were women (59% vs 32%; P<.01). The serum HCV RNA titer was significantly lower in patients with normal ALT levels (P<.01 vs in patients with elevated ALT levels). Patients with normal ALT levels had significantly lower inflammation and fibrosis scores on liver biopsy examination than patients with elevated ALT levels, but almost two-thirds had portal fibrosis and 10% had bridging fibrosis. No correlation between baseline ALT activity, HCV RNA level, and liver histology was observed in patients with normal ALT levels. During the 72-week follow-up period, ALT activity elevated above the upper limit of normal in 53% of the untreated patients with normal levels of ALT. None became HCV RNA undetectable. CONCLUSIONS: Chronic hepatitis C patients with normal ALT levels should be evaluated in a similar manner as patients with elevated ALT levels because they are at risk for developing significant liver disease. The decision to treat with peginterferon alfa and ribavirin should be based on multiple factors, rather than on ALT levels alone.     

A tracer kinetic model for 18F-FHBG for quantitating herpes simplex virus type 1 thymidine kinase reporter gene expression in living animals using PET.

Reporter probe 9-(4-18F-fluoro-3-[hydroxymethyl]butyl)guanine (18F-FHBG) and reporter gene mutant herpes simplex virus type 1 thymidine kinase (HSV1-sr39tk) have been used for imaging reporter gene expression with PET. Current methods for quantitating the images using the percentage injected dose per gram of tissue do not distinguish between the effects of probe transport and subsequent phosphorylation. We therefore investigated tracer kinetic models for 18F-FHBG dynamic microPET data and noninvasive methods for determining blood time-activity curves in an adenoviral gene delivery model in mice. METHODS: 18F-FHBG (approximately 7.4 MBq [approximately 200 microCi]) was injected into 4 mice; 18F-FHBG concentrations in plasma and whole blood were measured from mouse heart left ventricle (LV) direct sampling. Replication-incompetent adenovirus (0-2 x 10(9) plaque-forming units) with the E1 region deleted (n = 8) or replaced by HSV1-sr39tk (n = 18) was tail-vein injected into mice. Mice were dynamically scanned using microPET (approximately 7.4 MBq [approximately 200 microCi] 18F-FHBG) over 1 h; regions of interest were drawn on images of the heart and liver. Serial whole blood 18F-FHBG concentrations were measured in 6 of the mice by LV sampling, and 1 least-squares ratio of the heart image to the LV time-activity curve was calculated for all 6 mice. For 2 control mice and 9 mice expressing HSV1-sr39tk, heart image (input function) and liver image time-activity curves (tissue curves) were fit to 2- and 3-compartment models using Levenberg-Marquardt nonlinear regression. The models were compared using an F statistic. HSV1-sr39TK enzyme activity was determined from liver samples and compared with model parameter estimates. For another 3 control mice and 6 HSV1-sr39TK-positive mice, the model-predicted relative percentage of metabolites was compared with high-performance liquid chromatography analysis. RESULTS: The ratio of 18F-FHBG in plasma to whole blood was 0.84 +/- 0.05 (mean +/- SE) by 30 s after injection. The least-squares ratio of the heart image time-activity curve to the LV time-activity curve was 0.83 +/- 0.02, consistent with the recovery coefficient for the partial-volume effect (0.81) based on independent measures of heart geometry. A 3-compartment model best described 18F-FHBG kinetics in mice expressing HSV1-sr39tk in the liver; a 2-compartment model best described the kinetics in control mice. The 3-compartment model parameter, k3, correlated well with the HSV1-sr39TK enzyme activity (r2 = 0.88). CONCLUSION: 18F-FHBG equilibrates rapidly between plasma and whole blood in mice. Heart image time-activity curves corrected for partial-volume effects well approximate LV time-activity curves and can be used as input functions for 2- and 3-compartment models. The model parameter k3 from the 3-compartment model can be used as a noninvasive estimate for HSV1-sr39TK reporter protein activity and can predict the relative percentage of metabolites.     

Abdominal chemo- and mechanosensitivity in ruminants and its role in the control of food intake.

Ruminant animals have evolved a large and complex set of stomachs which allow fermentation of fibrous food by symbiotic micro-organisms. These stomachs are well innervated and generate signals which are thought to be important in the control of voluntary food intake. Tension receptors in the muscular wall of the rumen and reticulum are slowly adapting and provide a measure of distension while epithelial receptors are rapidly adapting and provide information on the fibrousness of the digesta; they are involved in the control of stomach motility and voluntary food intake in order to prevent excessive distension. The epithelial receptors are also sensitive to the chemical nature of the digesta, particularly acidity. There are mechano- and chemoreceptors in the abomasum (true stomach) and duodenum and chemoreceptors in the liver, all of which have been implicated in the control of intake. It is relatively easy to prepare and maintain ruminants with a rumen fistula and many studies have shown the effects of such manipulations as distension of balloons in the rumen on voluntary intake. With fibrous, slowly digested feeds intake is primarily limited by rumen distension. With more rapidly digested feeds, however, the products of digestion play an important role in controlling intake. Short-chain fatty acids are the main products of fermentation and infusion of their salts into the rumen depresses food intake to a much greater extent than infusion into the general circulation. Acetate or propionate given into the rumen are more effective, mole for mole, than butyrate but must be given at rates exceeding the natural rate of production in order to have a significant effect. It has been suggested that much of the effect of sodium acetate is via the increase in the osmolality of rumen fluid but there is considerable uncertainty as to the physiological significance of osmotic effects, especially when animals have free access to water and can prevent excessive increases in tonicity by increasing their water intake. Other constituents of rumen fluid have been implicated in the control of food intake, particularly lactic acid and nitrogenous compounds, especially as these can be found in fermented feeds such as silage. The omasum controls the flow of digesta to the abomasum; it is therefore well placed to control rumen fill and thus intake but there has been little study in this area and this is also true for the abomasum.(ABSTRACT TRUNCATED AT 400 WORDS)     

Identifying the special needs of children with Type 1 diabetes in the school setting. An overview of parents' perceptions.

AIMS: The aims of this observational study were to identify the special needs of children with Type 1 diabetes in schools from the parents' point of view and the difficulties experienced with full integration, and to define a series of interventions which may improve the situation. METHODS: Parents of children aged 3-18 years with Type 1 diabetes were eligible. Those who agreed to participate completed a self-reporting questionnaire which determined the effects of the disease on children, parents and school personnel, and addressed aspects including children's integration, glycaemic control, insulin administration, meals, sports, trips and attitudes of teachers and school colleagues to their disease. RESULTS: A total of 499 questionnaires were completed and validated. Median age of children was 11.5 years (95% CI 7.8-15.2). Only 34% of parents believed that teachers could recognize the symptoms of a mild hypoglycaemic episode. Seventeen per cent of parents experienced problems at their schools when they informed staff about their children's disease, 5% were finally not accepted and 8% were forced to change school. In some cases, they had to modify glucose monitoring (9%) and treatment administration (16%) because of a lack of cooperation from the school. CONCLUSIONS: Training sessions on Type 1 diabetes, an increase in the number of nurses, better availability of resources from diabetic associations to schools and improved communication between school personnel and parents were identified as key factors that may improve the full integration of the diabetic child in this setting.     

Cocaine use among heroin users in Spain: the diffusion of crack and cocaine smoking. Spanish Group for the Study on the Route of Administration of Drugs

STUDY OBJECTIVE: To describe the prevalence and patterns of use of crack and cocaine hydrochloride among heroin users in Spain. To explore if the expansion of heroin smoking is accompanied by a similar phenomenon for cocaine. DESIGN: Cross sectional study in 1995. Face to face interviews using a structured questionnaire. SETTING: Three cities with different prevalences of heroin use by smoking: high (Seville), intermediate (Madrid), and low (Barcelona). PARTICIPANTS: 909 heroin users, 452 in treatment and 457 out of treatment. MAIN RESULTS: Last month prevalence of crack use was 62.3% in Seville, 19.4% in Madrid, and 7.7% in Barcelona. Most users in Madrid (86.5%) and Barcelona (100%) generally prepared their own crack, usually with ammonia as alkali; in Seville most users (69.7%) bought preprocessed crack. The proportion of users who began taking cocaine (crack or cocaine hydrochloride) by smoking has increased progressively since the seventies, rising to 74.1% in Seville, 61.5% in Madrid, and 28% in Barcelona in 1992-1995, with the earliest increase in Seville. The factors associated with crack use were: residence in Seville (odds ratio (OR) = 16.3), cocaine hydrochloride use mainly by smoking (OR = 5.0), by sniffing (OR = 2.7) or by injecting (OR = 2.5), heroin use mainly by smoking (OR = 2.8) and weekly use of cannabis (OR = 1.9). CONCLUSIONS: In Spain smoking cocaine may be progressively diffusing from the south west to the north east, similar to what has happened with smoking heroin, but beginning later in time. The factors associated with smoking cocaine are basically ecological or cultural in nature (characteristics of the available drugs and the main route of heroin administration in each city).

 

     

Currant allergy and the Rosaceae-grass pollen allergy syndrome: a case report.

BACKGROUND: Despite the increasing use of currants in culinary recipes, currant allergy has rarely been reported. OBJECTIVES: To study a case of currant allergy and to explore cross-reactivity between grass pollen and Rosaceae family fruit allergens. METHODS: Skin prick tests to pollen and skin prick-to-prick tests with currants and peach were performed. Specific IgE levels were determined using the CAP method. We prepared a protein extract of 0.1 mg/mL in phosphate-buffered saline using red currant in the presence of protease inhibitors. Immunoblot inhibition studies were performed to explore cross-reactivity between grass pollen and currant allergens. RESULTS: Skin prick test results were positive to Dactylis, arizonic, and olive pollens. Results of skin prick-to-prick tests with fresh red and black currants were negative and positive, respectively, to peach. The specific IgE level was 5.7 KU/L to red currant and 2.92 KU/L to peach (CAP). Western blot analysis with red currant extract revealed specific IgE protein bands of 37 and 26 kDa. Preincubation of sera with extracts from red currant and peach inhibited both IgE bands, and preincubation with Dactylis pollen inhibited the 37-kDa band only. CONCLUSIONS: We report a case of allergy to grass pollen with an oral allergy syndrome involving several fruits from 2 different families of the Rosidae subclass confirmed by in vitro tests. Inhibition studies demonstrated cross-reactivity between different fruits (currant and raspberry) from the Rosidae subclass and were incomplete with grass pollen allergens.