Molecular mechanisms of endotoxin activity

Endotoxin (lipopolysaccharide, LPS), a constitutent of the outer membrane of the cell wall of gramnegative bacteria, exerts a wide variety of biological effects in humans. This review focuses on the molecular mechanisms underlying these activities and discusses structure-function relationships of the endotoxin molecule, its interaction with humoral and cellular receptors involved in cell activation, and transmembrane and intra-cellular signal transduction pathways.     

Cultivation of the warble-fly Oestromyia leporina pall. (Diptera, Hypodermatidae) and its biological prerequisites (author's transl)]

The warble-fly Oestromyia leporina was cultivated for four generations in the laboratory. In the present paper the technic of laboratory mating and the modus of experimental infection of the host are described. The fertility of females is tested by experiments and by dissections. It is shown how the diapause of the puparia can be shortened and how it can be omitted. The successful infection of several species of small mammals demonstrates that O. leporina can be colonized not only on the natural host but also on some common laboratory animals like mice and rats.     

Y Chromosomal Variation Tracks the Evolution of Mating Systems in Chimpanzee and Bonobo

The male-specific regions of the Y chromosome (MSY) of the human and the chimpanzee (Pan troglodytes) are fully sequenced. The most striking difference is the dramatic rearrangement of large parts of their respective MSYs. These non-recombining regions include ampliconic gene families that are known to be important for male reproduction,and are consequently under significant selective pressure. However, whether the published Y-chromosomal pattern of ampliconic fertility genes is invariable within P. troglodytes is an open but fundamental question pertinent to discussions of the evolutionary fate of the Y chromosome in different primate mating systems. To solve this question we applied fluorescence in situ hybridisation (FISH) of testis-specific expressed ampliconic fertility genes to metaphase Y chromosomes of 17 chimpanzees derived from 11 wild-born males and 16 bonobos representing seven wild-born males. We show that of eleven P. troglodytes Y-chromosomal lines, ten Y-chromosomal variants were detected based on the number and arrangement of the ampliconic fertility genes DAZ (deleted in azoospermia) and CDY (chromodomain protein Y)—a so-far never-described variation of a species'' Y chromosome. In marked contrast, no variation was evident among seven Y-chromosomal lines of the bonobo, P. paniscus, the chimpanzee''s closest living relative. Although, loss of variation of the Y chromosome in the bonobo by a founder effect or genetic drift cannot be excluded, these contrasting patterns might be explained in the context of the species'' markedly different social and mating behaviour. In chimpanzees, multiple males copulate with a receptive female during a short period of visible anogenital swelling, and this may place significant selection on fertility genes. In bonobos, however, female mate choice may make sperm competition redundant (leading to monomorphism of fertility genes), since ovulation in this species is concealed by the prolonged anogenital swelling, and because female bonobos can occupy high-ranking positions in the group and are thus able to determine mate choice more freely.     

Prevalence of Epstein-Barr virus (EBV) antibodies in primate stocks of zoological gardens

Abstract: Examination of 387 serum samples from 41 primate species with two different ELISAs for the presence of IgG-antibodies against Epstein-Barr virus. Antibodies were detected in 15 out of 32 species of Old World primates and none in six species of New World primates by screening ELISA (Enzygnost, Behringwerke AG, Marburg), a testkit for human diagnostics. To avoid species-dependent factors which could influence the sensitivity of the Enzygnost assay, a competition ELISA was established. The modified test assessed antibodies in all species of Old World primates and three species of the New World primates.     

Prevalence of Depression,Suicidal Ideation,Alcohol Intake and Nicotine Consumption in Rural Central India. The Central India Eye and Medical Study

Background

To investigate the prevalence of depression, suicidal ideations, alcohol and nicotine consumption in adults in an agrarian society mostly unchanged by the effects of urbanization.

Methods

The Central India Eye and Medical Study is a population-based study in rural Central India close to the tribal belt and included 4711 subjects (aged 30+ years). Depression was assessed by the Center for Epidemiologic Studies Depression Scale (CESD), suicidal ideation by six standardized questions, nicotine use by the Fagerstroem Nicotine Tolerance Questionnaire (FTNQ), and alcohol consumption by the Alcohol Use Disorders Identification Test (AUDIT).

Results

Mild to moderate depression (CESD sum score: 15–21) was detected in 1862 (39.6%) individuals (33.5% of men, 44.8 of women), and major depression (CESD sum score >21) in 613 (13.0%) individuals (8.1 of men, 17.3% of women). Suicide attempt was reported by 199 (4.2%) participants and suicidal thoughts during the last 6 months by 238 (5.1%) individuals. There were 887 (18.9%) smokers and smokeless tobacco was consumed by 1968 (41.8%) subjects. Alcohol consumption was reported by 1081 (23.0%) participants; 283 (6.0%) subjects had an AUDIT score ≥8 (hazardous drinking), and 108 (4.63%) subjects a score ≥13 (women) or ≥15 (men) (alcohol dependence).

Conclusions

In rural Central India, prevalence of major depression was comparable to figures reported from other developing countries. Prevalence of smoking and hazardous alcohol consumption was higher than as reported from urban regions. Measures should be taken to address the relatively high prevalence of suicide attempts and thoughts on suicide in rural Central India.     

Synthetic and natural Escherichia coli free lipid A express identical endotoxic activities

The recently chemically synthesized Escherichia coli lipid A and the natural free lipid A of E. coli were compared with respect to their endotoxic activities in the following test systems: lethal toxicity, pyrogenicity, local Shwartzman reactivity, Limulus amoebocyte lysate gelation capacity, tumour necrotizing activity, B cell mitogenicity, induction of prostaglandin synthesis in macrophages, and antigenic specificity. It was found that synthetic and natural free lipid A exhibit identical activities and are indistinguishable in all tests.     

Structural investigations on the inner core region of lipopolysaccharides from Salmonella minnesota rough mutants

The structure of the inner core region (L-glycero-D-mannoheptose/2-keto-3-deoxy-D-mannooctulosonic acid region) of lipopolysaccharides from Salmonella minnesota rough mutants was investigated. Using conventional methods (neutral sugar analysis, Smith degradation and methylation analysis) combined with gas chromatography/mass spectrometry (GC/MS) of higher oligosaccharides (up to tetrasaccharide), the linkages of the core sugars of lipopolysaccharides from S. minnesota rough mutants, strains R4 (Rd2P-), R7 (Rd1P-) and R5 (RcP-) were determined as: (formula see text) with R representing H in R4, L-glycero-D-mannoheptopyranosyl in R7, and D-glucopyranosyl-(1----3)-L-glycero-D-mannoheptopyranosyl in R5, respectively. In addition, it is shown that heterogeneity within the neutral sugar part of these lipopolysaccharides is low.