Studies on sperm storage in the vas deferens of the spinifex hopping mouse (Notomys alexis)

The cauda epididymidis, with its relatively cool temperature (32-35 degrees C), is considered to be the main site of sperm storage in male mammals. However, in the adult male spinifex hopping mouse, Notomys alexis, similar numbers of spermatozoa are found in the vas deferens to those in the cauda epididymidis. The present study shows that, unlike in the laboratory mouse in which spermatozoa of the vas deferens are found mainly in the epididymal region of the duct, spermatozoa in the hopping mouse are localized mainly to the middle and urethral regions of the vas deferens which lies in the inguinal and lower abdominal region of the body cavity. After ligation of the vas deferens close to its connection with the epididymis, many spermatozoa in the vas deferens retain the potential for motility for up to 2 weeks, indicating that the viability of spermatozoa is not compromised by being restricted to core body temperature. This urethral region of the vas deferens, in which spermatozoa reside, has a highly divergent structural organization compared with that of common laboratory rodents in which there is an expanded lumen with a network of epithelial folds. Ultrastructural observations of the cells lining the duct indicate that there are not any marked differences in morphology compared with the cells lining the duct in common laboratory murids, but the infoldings of the vas deferens of the hopping mouse are highly vascular which might facilitate supply of oxygen and nutrients to the spermatozoa residing in the lumen.     

Molecular cloning and characterization of an invertebrate homologue of a neuropeptide Y receptor

Neuropeptide Y is an abundant and physiologically important peptide in vertebrates having effects on food intake, sexual behaviour, blood pressure and circadian rhythms. Neuropeptide Y homologues have been found in invertebrates, where they are very likely to play similar, important roles. Although five neuropeptide Y-receptor subtypes have been identified in mammals, none has been reported from invertebrates. Here we describe the cloning of a neuropeptide Y-receptor from the brain of the snail Lymnaea stagnalis. The identity of the receptor was deduced by expressing the neuropeptide Y-receptor-encoding cDNA in Chinese Hamster Ovary cells, which were subsequently challenged with size-fractionated Lymnaea brain extracts. An active peptide, selected on the basis of its ability to induce changes in cAMP levels, was purified to homogeneity, analysed by mass spectrometry and amino acid sequence determination, and turned out to be a Lymnaea homologue of neuropeptide Y.     

Survival of Mycobacterium paratuberculosis and preservation of immunoglobulin G in bovine colostrum under experimental conditions simulating pasteurization

OBJECTIVE: To determine whether Mycobacterium paratuberculosis could survive in colostrum after pasteurization. Additionally, this study investigated the effect pasteurization had on IgG concentration in colostrum. ANIMALS: Colostrum samples were collected from cattle (beef and dairy) owned by the state of Ohio. PROCEDURE: Colostrum was divided into aliquots and inoculated with variable concentrations of M paratuberculosis (ATCC No. 19698: 10(4), 10(3), and 10(2) colony-forming units/ml). Half the samples at each concentration were subjected to pasteurization temperatures (63 C) for 30 minutes and the remainder were kept at approximately 20 to 23 C. All samples were incubated (Herrold's egg yolk medium with and without mycobactin J) and observed for growth during the next 16 weeks. Additionally, the IgG concentration of colostrum was determined by radioimmunoassay before and after pasteurization. Samples that coagulated at pasteurization temperatures were mechanically resuspended before measurement of IgG concentration. RESULTS: Growth of M paratuberculosis was retarded but not eliminated by pasteurization. Growth was observed in all unpasteurized samples incubated on Herrold's egg yolk medium with mycobactin J but in only 2 of 18 pasteurized samples similarly cultured. Growth from pasteurized samples appeared 5 to 9 weeks after growth was observed from nonpasteurized samples. Mean colostral IgG concentration was 44.4 g/L in nonpasteurized samples and 37.2 g/L in pasteurized samples, a decrease of 12.3%. High-quality colostrum (> 48 g of IgG/L) had a significantly greater loss of IgG concentration than did colostrum of lesser quality (P = 0.002). CONCLUSIONS: Pasteurization lessened, but did not eliminate, growth of M paratuberculosis from experimentally inoculated colostrum samples. Pasteurization resulted in a significant decrease in colostral IgG concentration but not to an unmanageable level that would preclude the colostrum's use for passive transfer of immunity. CLINICAL RELEVANCE: Colostrum is macrophage rich and may serve as a source of M paratuberculosis infection to calves. Pasteurization of colostrum may lessen the risk of infection, but will not totally eliminate M paratuberculosis.     

Fluvoxamine in the treatment of binge-eating disorder: a multicenter placebo-controlled, double-blind trial

OBJECTIVE: The purpose of this study was to assess the efficacy of fluvoxamine in the treatment of binge-eating disorder. Binge-eating disorder is a newly described eating disorder characterized by recurrent episodes of binge eating but without purging behaviors. Uncontrolled reports have suggested that serotonin selective reuptake inhibitors (SSRIs) may be effective in treating this disorder. METHOD: Eighty-five outpatients with a DSM-IV diagnosis of binge-eating disorder were randomly assigned to receive either fluvoxamine (N=42) or placebo (N=43) in a 9-week, parallel-group, double-blind, flexible dose (50-300 mg) study at three centers. The primary outcome measures were frequency of binge eating, expressed as log ([binges/week]+1), and Clinical Global Impression (CGI) scale ratings. Secondary measures included the level of response (based on the percentage change in frequency of binges), body mass index, and Hamilton Rating Scale for Depression score. Except for the level of response, the outcome measures were analyzed by random regression methods; the treatment-by-time interaction was the measure of treatment effect. RESULTS: Compared with placebo, fluvoxamine was associated with a significantly greater rate of reduction in the frequency of binges, rate of reduction in CGI severity scores, rate of increase in CGI improvement scores, level of response for patients who completed the 9-week study, and rate of reduction in body mass index. There was no significant difference between placebo and fluvoxamine groups in the rate of decrease in Hamilton depression scale scores. A significantly greater proportion of patients receiving fluvoxamine than those receiving placebo discontinued treatment because of an adverse medical event. CONCLUSIONS: In this placebo-controlled trial, fluvoxamine was found to be effective according to most outcome measures in the acute treatment of binge-eating disorder.     

Two dual-specific (anti-IgG and anti-dsDNA) monoclonal autoantibodies derived from the NZB/NZW F1 recognize an epitope in the hinge region

The anti-IgG properties of two dual-specific (anti-dsDNA and anti-IgG) monoclonal NZB/NZW F1-derived autoantibodies, BV 17-45 and BV 16-13, were studied to resolve the location and possible commonality of the IgG epitope. To determine if BV 17-45 and BV 16-13 recognized the same IgG epitope, the relative temperature sensitivity of the conformational IgG epitopes were evaluated using the conformational sensitive immunoassay. Comparison of the temperature sensitivity of the conformational immunoglobulin epitopes over a temperature range of 25-100 degrees C suggested that the epitope recognized by BV 17-45 was the same as the IgG epitope recognized by BV 16-13. Further studies with papain- and pepsin-generated F(ab')2, Fab, and Fc fragments of BV 17-45 and BV 16-13 revealed that the dual-specific autoantibodies BV 17-45 and BV 16-13 both bound an epitope in the hinge region of the IgG molecule. The potential correlation between these studies and the pathogenic nature of dual-specific autoantibodies is discussed.     

The granaticin biosynthetic gene cluster of Streptomyces violaceoruber Tü22: sequence analysis and expression in a heterologous host

BACKGROUND: The granaticins are members of the benzoisochromanequinone class of aromatic polyketides, the best known member of which is actinorhodin made by Streptomyces coelicolor A3(2). Genetic analysis of this class of compounds has played a major role in the development of hypotheses about the way in which aromatic polyketide synthases (PKSs) control product structure. Although the granaticin nascent polyketide is identical to that of actinorhodin, post-PKS steps involve different pyran-ring stereochemistry and glycosylation. Comparison of the complete gene clusters for the two metabolites is therefore of great interest. RESULTS: The entire granaticin gene cluster (the gra cluster) from Streptomyces violaceoruber T-22 was cloned on either of two overlapping cosmids and expressed in the heterologous host, Streptomyces coelicolor A3(2), strain CH999. Chemical analysis of the recombinant strains demonstrated production of granaticin, granaticin B, dihydrogranaticin and dihydrogranaticin B, which are the four known metabolites of S. violaceoruber. Analysis of the complete 39,250 base pair sequence of the insert of one of the cosmids, pOJ466-22-24, revealed 37 complete open reading frames (ORFs), 15 of which resemble ORFs from the act (actinorhodin) gene cluster of S. coelicolor A3(2). Among the rest, nine resemble ORFs potentially involved in deoxysugar metabolism from Streptomyces spp. and other bacteria, and six resemble regulatory ORFs. CONCLUSIONS: On the basis of these resemblances, putative functional assignments of the products of most of the newly discovered ORFs were made, including those of genes involved in the PKS and tailoring steps in the biosynthesis of the granaticin aglycone, steps in the deoxy sugar pathway, and putative regulatory and export functions.