Systematic shut-off of the hormone receptors in intraspecific adrenal x Leydig cell hybrids

The mouse Y1 adrenal cell line was fused with mouse Leydig cells in primary culture. The selected hybrids were examined for their response to gonadotropin (hCG) and ACTH. None of them bound specifically [125I]hCG, nor did they augment their cAMP production in response to gonadotropin or ACTH stimulation, whereas their adenylate cyclase remained responsive to forskolin and cholera toxin, thus indicating a repression of hCG receptor synthesis and probably a loss of ACTH receptors, rather than a lesion of the coupling between the hormone receptor complex and the adenylate cyclase. Basal pregnenolone production in 17 hybrids was close to that of Leydig and Y1 cells and was enhanced after 8-bromo adenosine 3',5'-monophosphate (8-Br-cAMP) stimulation in 11 of them. Therefore, the negative control leading to the extinction of both parental functions acts preferentially at the first step of steroidogenesis, i.e., the gene(s) coding for the hormone receptors.     

Assessment of Efficacy and Quality of Two Albendazole Brands Commonly Used against Soil-Transmitted Helminth Infections in School Children in Jimma Town,Ethiopia

BackgroundThere is a worldwide upscale in mass drug administration (MDA) programs to control the morbidity caused by soil-transmitted helminths (STHs): Ascaris lumbricoides, Trichuris trichiura and hookworm. Although anthelminthic drugs which are used for MDA are supplied by two pharmaceutical companies through donation, there is a wide range of brands available on local markets for which the efficacy against STHs and quality remain poorly explored. In the present study, we evaluated the drug efficacy and quality of two albendazole brands (Bendex and Ovis) available on the local market in Ethiopia.Conclusion/SignificanceThe study revealed that differences in efficacy between the two brands of albendazole (ABZ) tablets against hookworm are linked to the differences in the in-vitro drug release profile. Differences in uptake and metabolism of this benzimidazole drug among different helminth species may explain that this efficacy difference was only observed in hookworms and not in the two other species. The results of the present study underscore the importance of assessing the chemical and physicochemical quality of drugs before conducting efficacy assessment in any clinical trials to ensure appropriate therapeutic efficacy and to exclude poor drug quality as a factor of reduced drug efficacy other than anthelminthic resistance. Overall, this paper demonstrates that “all medicines are not created equal”.     

Facial width-to-height ratio predicts self-reported dominance and aggression in males and females,but a measure of masculinity does not

Recently, associations between facial structure and aggressive behaviour have been reported. Specifically, the facial width-to-height ratio (fWHR) is thought to link to aggression, although it is unclear whether this association is related to a specific dimension of aggression, or to a more generalized concept of dominance behaviour. Similarly, an association has been proposed between facial masculinity and dominant and aggressive behaviour, but, to date, this has not been formally tested. Because masculinity and fWHR are negatively correlated, it is unlikely that both signal similar behaviours. Here, we thus tested these associations and show that: (i) fWHR is related to both self-reported dominance and aggression; (ii) physical aggression, verbal aggression and anger, but not hostility are associated with fWHR; (iii) there is no evidence for a sex difference in associations between fWHR and aggression; and (iv) the facial masculinity index does not predict dominance or aggression. Taken together, these results indicate that fWHR, but not a measure of facial masculinity, cues dominance and specific types of aggression in both sexes.     

The parasite's long arm: a tapeworm parasite induces behavioural changes in uninfected group members of its social host

Parasites can induce alterations in host phenotypes in order to enhance their own survival and transmission. Parasites of social insects might not only benefit from altering their individual hosts, but also from inducing changes in uninfected group members. Temnothorax nylanderi ant workers infected with the tapeworm Anomotaenia brevis are known to be chemically distinct from nest-mates and do not contribute to colony fitness, but are tolerated in their colonies and well cared for. Here, we investigated how tapeworm- infected workers affect colony aggression by manipulating their presence in ant colonies and analysing whether their absence or presence resulted in behavioural alterations in their nest-mates. We report a parasite-induced shift in colony aggression, shown by lower aggression of uninfected nest-mates from parasitized colonies towards conspecifics, potentially explaining the tolerance towards infected ants. We also demonstrate that tapeworm-infected workers showed a reduced flight response and higher survival, while their presence caused a decrease in survival of uninfected nest-mates. This anomalous behaviour of infected ants, coupled with their increased survival, could facilitate the parasites'' transmission to its definitive hosts, woodpeckers. We conclude that parasites exploiting individuals that are part of a society not only induce phenotypic changes within their individual hosts, but in uninfected group members as well.     

Antibacterial and immunomodulatory activities of bovine lactoferrin against <Emphasis Type="Italic">Escherichia coli</Emphasis> O157:H7 infections in cattle

Enterohemorrhagic Escherichia coli (EHEC) O157:H7 is a zoonotic pathogen that causes food-borne disease in humans ranging from watery diarrhea to bloody diarrhea and severe hemorrhagic colitis, renal failure and hemolytic uremic syndrome. Cattle, the most important source of E. coli O157:H7 transmission to humans, harbor the bacteria in their gastrointestinal tract without showing clinical symptoms. Prevention of E. coli O157:H7 infections in ruminants could diminish the public health risk. However, there is no specific treatment available nor a vaccine or a therapeutic agent which completely prevents E. coli O157:H7 infections in cattle. This paper provides an overview of latest research data on eradicating enterohemorrhagic E. coli O157:H7 in ruminants by use of bovine lactoferrin administration. The article provides insights into the anti-microbial and immunomodulatory activities of bovine lactoferrin against E. coli O157:H7 infections in cattle.     

Development of two PCR assays for the identification of mycoplasmas causing contagious agalactia

Abstract A new detection test for the mycoplasmas causing contagious agalactia, Mycoplasma agalactiae , M. capricolum subsp. capricolum and M. mycoides subsp. mycoldes L.C., was developed. It was based on two polymerase chain reaction assays: the Ma-PCR for the detection of M. agalactiae and the MYC-PCR for the 'mycoides cluster' thus including M. capricolum subsp. capricolum and M. mycoides subsp. mycoides L.C. An M. agalactiae strain was identified by a 933-bp Ma-PCR product and no amplification with the MYC-PCR. In contrast, a 460-bp MYC-PCR product and a negative or a 350-bp Ma-PCR product characterized a 'mycoides cluster' strain. M. capricolum subsp. capricolum and M. mycoides subsp. mycoides L.C. were identified by their species-specific Asel pattern of the 460-bp MYC-PCR product.     

The Western Aleutians: Cultural Isolation and Environmental Change

Recent research in the western Aleutians addresses two primary issues: the nature and extent of cultural exchange along the Aleutian chain, and Holocene environmental change and its effects on the development of Aleut culture. Cultural isolation is a major paradigm of researchers working in the Aleutians. Review of the distribution of several cultural traits suggests the Aleuts adopted many cultural elements originating outside the chain, but the distribution of these to the western islands was uneven.     

Diversity and Ecology of Viruses in Hyperarid Desert Soils

In recent years, remarkable progress has been made in the field of virus environmental ecology. In marine ecosystems, for example, viruses are now thought to play pivotal roles in the biogeochemical cycling of nutrients and to be mediators of microbial evolution through horizontal gene transfer. The diversity and ecology of viruses in soils are poorly understood, but evidence supports the view that the diversity and ecology of viruses in soils differ substantially from those in aquatic systems. Desert biomes cover ∼33% of global land masses, and yet the diversity and roles of viruses in these dominant ecosystems remain poorly understood. There is evidence that hot hyperarid desert soils are characterized by high levels of bacterial lysogens and low extracellular virus counts. In contrast, cold desert soils contain high extracellular virus titers. We suggest that the prevalence of microbial biofilms in hyperarid soils, combined with extreme thermal regimens, exerts strong selection pressures on both temperate and virulent viruses. Many desert soil virus sequences show low values of identity to virus genomes in public databases, suggesting the existence of distinct and as-yet-uncharacterized soil phylogenetic lineages (e.g., cyanophages). We strongly advocate for amplification-free metavirome analyses while encouraging the classical isolation of phages from dominant and culturable microbial isolates in order to populate sequence databases. This review provides an overview of recent advances in the study of viruses in hyperarid soils and of the factors that contribute to viral abundance and diversity in hot and cold deserts and offers technical recommendations for future studies.     

Does Syntactic Alignment Effectively Influence How Speakers Are Perceived by Their Conversation Partner?

The way we talk can influence how we are perceived by others. Whereas previous studies have started to explore the influence of social goals on syntactic alignment, in the current study, we additionally investigated whether syntactic alignment effectively influences conversation partners’ perception of the speaker. To this end, we developed a novel paradigm in which we can measure the effect of social goals on the strength of syntactic alignment for one participant (primed participant), while simultaneously obtaining usable social opinions about them from their conversation partner (the evaluator). In Study 1, participants’ desire to be rated favorably by their partner was manipulated by assigning pairs to a Control (i.e., primed participants did not know they were being evaluated) or Evaluation context (i.e., primed participants knew they were being evaluated). Surprisingly, results showed no significant difference in the strength with which primed participants aligned their syntactic choices with their partners’ choices. In a follow-up study, we used a Directed Evaluation context (i.e., primed participants knew they were being evaluated and were explicitly instructed to make a positive impression). However, again, there was no evidence supporting the hypothesis that participants’ desire to impress their partner influences syntactic alignment. With respect to the influence of syntactic alignment on perceived likeability by the evaluator, a negative relationship was reported in Study 1: the more primed participants aligned their syntactic choices with their partner, the more that partner decreased their likeability rating after the experiment. However, this effect was not replicated in the Directed Evaluation context of Study 2. In other words, our results do not support the conclusion that speakers’ desire to be liked affects how much they align their syntactic choices with their partner, nor is there convincing evidence that there is a reliable relationship between syntactic alignment and perceived likeability.     

On the formulation of discrete-time epidemic models

Jacquez constructed a properly posed, more general model for the Reed-Frost epidemic process by assuming independent behaviors for the susceptibles and introducing the generating function for the number of contacts per person. An alternative approach is proposed here that relies on similar hypotheses for the infectives and allows the usual chain-binomial structure of the infection process to be extended. For this new model, the derivation of the final size and the threshold phenomenon becomes much simpler. A detailed analysis and its generalization to heterogeneous populations and continuous-time models will be the subject of a forthcoming paper.