Diallel analysis for sex-linked and maternal effects

Genetic models including sex-linked and maternal effects as well as autosomal gene effects are described. Monte Carlo simulations were conducted to compare efficiencies of estimation by minimum norm quadratic unbiased estimation (MINQUE) and restricted maximum likelihood (REML) methods. MINQUE(1), which has 1 for all prior values, has a similar efficiency to MINQUE(), which requires prior estimates of parameter values. MINQUE(1) has the advantage over REML of unbiased estimation and convenient computation. An adjusted unbiased prediction (AUP) method is developed for predicting random genetic effects. AUP is desirable for its easy computation and unbiasedness of both mean and variance of predictors. The jackknife procedure is appropriate for estimating the sampling variances of estimated variances (or covariances) and of predicted genetic effects. A t-test based on jackknife variances is applicable for detecting significance of variation. Worked examples from mice and silkworm data are given in order to demonstrate variance and covariance estimation and genetic effect prediction.     

The enzymatic basis for pesticide bioremediation

Enzymes are central to the biology of many pesticides, influencing their modes of action, environmental fates and mechanisms of target species resistance. Since the introduction of synthetic xenobiotic pesticides, enzymes responsible for pesticide turnover have evolved rapidly, in both the target organisms and incidentally exposed biota. Such enzymes are a source of significant biotechnological potential and form the basis of several bioremediation strategies intended to reduce the environmental impacts of pesticide residues. This review describes examples of enzymes possessing the major activities employed in the bioremediation of pesticide residues, and some of the strategies by which they are employed. In addition, several examples of specific achievements in enzyme engineering are considered, highlighting the growing trend in tailoring enzymatic activity to a specific biotechnologically relevant function.     

Effect of antibiotics on lysine production in free and immobilized cells of Bacillus subtilis

Summary In immobilized cell preparations growth of cells outside the immobilization matrix as free cells is normally undesirable due to the appearance of cells in the product stream and clogging of such systems. Antibiotics could be used to arrest such free cell growth while allowing the synthesis and excretion of the product into the medium. Chloramphenicol (200 /ml) and/or novobiocin (10 /ml), when added during the growth of Bacillus subtilis allowed the production and excretion of lysine into the medium. Chloramphenicol at 200 /ml effectively arrested free cell growth and hence the lysine being produced was almost entirely due to immobilized cells. Novobiocin on the other hand at concentrations of 100 /ml, stopped free cell growth, but also prevented the production of l-lysine. Productivities and yields of lysine were adversely affected by chloramphenicol or novobiocin, probably due to a great decrease in cell viability.Offprint requests to: C. J. Israilides     

Investigation of factor Xa inhibitors containing non-amidine S1 elements

Several non-amidino S1 derivatives of the 1,2-diaminobenzene-based scaffold (4) were synthesized and evaluated for their ability to bind to the active site and inhibit the human protease factor Xa. A subset of these compounds were also evaluated for their anticoagulant effects in human plasma as measured by prothrombin time (PT).     

Evidence for the role of glycoprotein G of respiratory syncytial virus in binding of Neisseria meningitidis to HEp-2 cells

Abstract Viral glycoproteins G and F are expressed on the surface of cells infected with respiratory syncytial virus (RSV). We investigated the role of these proteins in the previously reported enhanced binding of Neisseria meningitidis to RSV-infected HEp-2 cells. Virus particles attached to bacteria were detected by immunofluorescence with flow cytometry. Binding of FITC-labelled bacteria to RSV-infected cells was significantly inhibited by monoclonal antibody against glycoprotein G. Unlabelled bacteria interfered with binding of the anti-G monoclonal antibody to these cells. These interactions were not found with a monoclonal antibody against glycoprotein F. We propose that glycoprotein G of RSV expressed on the surface of infected cells might act as an additional receptor for meningococci.     

Symptomatic gastro-oesophageal reflux disease: double blind controlled study of intermittent treatment with omeprazole or ranitidine. The European Study Group

ObjectiveTo assess intermittent treatment over 12 months in patients with symptomatic gastro-oesophageal reflux disease.DesignRandomised, multicentre, double blind, controlled study. Patients with heartburn and normal endoscopy results or mild erosive changes received omeprazole 10 mg or 20 mg daily or ranitidine 150 mg twice daily for 2 weeks. Patients remaining symptomatic had omeprazole 10 mg or ranitidine dose doubled for another 2 weeks while omeprazole 20 mg was continued for 2 weeks. Patients who were symptomatic or mildly symptomatic were followed up for 12 months. Recurrences of moderate or severe heartburn during follow up were treated with the dose which was successful for initial symptom control.SettingHospitals and primary care practices between 1994 and 1996.Subjects677 patients with gastro-oesophageal reflux disease.Results704 patients were randomised, 677 were eligible for analyses; 318 reached the end of the study with intermittent treatment without recourse to maintenance antisecretory drugs. The median number of days off active treatment during follow up was 142 for the entire study (281 for the 526 patients who reached a treatment related end point). Thus, about half the patients did not require treatment for at least 6 months, and this was similar in all three treatment groups. According to outcome, 378 (72%) patients were in the best outcome ranks (no relapse or one (or more) relapse but in remission until 12 months); 630 (93%) had three or fewer relapses in the intermittent treatment phase. Omeprazole 20 mg provided faster relief of heartburn. The results were similar in patients with erosive and non-erosive disease.ConclusionsIntermittent treatment is effective in managing symptoms of heartburn in half of patients with uncomplicated gastro-oesophageal reflux disease. It is simple and applicable in general practice, where most patients are seen.

Key messages

• Symptomatic gastro-oesophageal disease can be managed successfully in half of patients with intermittent treatment with antisecretory drugs
• Omeprazole 20 mg once daily gives more rapid relief of symptoms than either omeprazole 10 mg once daily or ranitidine 150 mg twice daily. However, the choice of antisecretory drug has little effect on the overall outcome
• Relapses are relatively infrequent and can be managed with short courses of repeat treatment
• Starting intermittent treatment with omeprazole 20 mg once daily is more cost effective than a dose titration approach with omeprazole 10 mg once daily or ranitidine 150 mg twice daily
• An intermittent treatment strategy is simple and applicable in general practice, where most of these patients are seen

     

Comparison of NK-1 Receptor Antagonist (Maropitant) to Morphine as a Pre-Anaesthetic Agent for Canine Ovariohysterectomy

Objective

To compare the NK-1 receptor antagonist maropitant to morphine during and after surgery in dogs undergoing ovariohysterectomy (OHE).

Methods

30 healthy female dogs were randomly divided to receive either a pre-anaesthetic dose of morphine (0.5 mg/kg SQ) or maropitant (1 mg/kg, SQ) prior to OHE. Anaesthesia was induced with propofol and maintained with isoflurane. Expired isoflurane concentration, heart rate (HR), systolic arterial pressure (SAP) and respiratory rate were measured. Post-operative pain scores and appetite were evaluated during the recovery period. Rescue analgesia (morphine 0.1 mg/kg IV) was administered as needed post-operatively based on blinded pain score assessments.

Results

Although clinically comparable; during surgical stimulation, the maropitant group had lower HR (108±18 vs 115±24 bpm; p = 0.04), lower SAP (114±23 vs 125±23 mmHg; p = 0.003) and required slightly lower percent of isoflurane anaesthetic (1.35±0.2 vs 1.51±0.4%; p = 0.005), when compared to the morphine group. In the recovery period, the maropitant group had lower pain scores at extubation (1.7±0.7 vs 3.4±2.3; p = 0.0001) and were more likely to eat within 3 hours after extubation (64.7 vs 15.3%). However, post-operative rescue analgesia requirements were similar between groups. All other measured parameters were similar between groups. The overall difference observed between groups was small and all monitored and measured parameters were within the expected range for anesthetized dogs.

Clinical Significance

No major differences in cardiorespiratory parameters or anaesthetic requirements were observed between maropitant and morphine when used as a pre-anesthetic agent for OHE. Further studies are necessary to fully elucidate the benefits of maropitant as a pre-anaesthetic agent for canine OHE.     

Analysis of factors that influence energy expenditure in honeyeaters (Meliphagidae)

The energy expenditure of the tūī (Prosthemadera novaeseelandiae), a meliphagid endemic to New Zealand, was measured and compared with 20 species of honeyeaters (family Meliphagidae) to determine whether its expenditure is influenced either by life in a moist, temperate climate or an island residence. Body mass in the honeyeaters accounted for 91.5% of the variation in basal rate. The combination of body mass, climate and the maximal limit to an altitudinal distribution explained 98.6% of the variation in basal rate with tropical, low-altitude species having the highest mass-independent rate. The basal rates of meliphagids in tropical highlands are similar to those in temperate lowlands, which may reflect similar food supplies. The tūī mass-independent expenditure appears to reflect an active lifestyle in a temperate climate with no evidence that an island residence influenced its rate, whereas sedentary birds on New Zealand have responded to island life with a depressed basal rate. An effective analysis of the variation in energy expenditure requires the inclusion of the ecological and behavioural characteristics that distinguish species.