Microbial ecology: human gut microbes associated with obesity

Two groups of beneficial bacteria are dominant in the human gut, the Bacteroidetes and the Firmicutes. Here we show that the relative proportion of Bacteroidetes is decreased in obese people by comparison with lean people, and that this proportion increases with weight loss on two types of low-calorie diet. Our findings indicate that obesity has a microbial component, which might have potential therapeutic implications.     

Social parasitism by male-producing reproductive workers in a eusocial insect

The evolution of extreme cooperation, as found in eusocial insects (those with a worker caste), is potentially undermined by selfish reproduction among group members. In some eusocial Hymenoptera (ants, bees and wasps), workers can produce male offspring from unfertilized eggs. Kin selection theory predicts levels of worker reproduction as a function of the relatedness structure of the workers' natal colony and the colony-level costs of worker reproduction. However, the theory has been only partially successful in explaining levels of worker reproduction. Here we show that workers of a eusocial bumble bee (Bombus terrestris) enter unrelated, conspecific colonies in which they then produce adult male offspring, and that such socially parasitic workers reproduce earlier and are significantly more reproductive and aggressive than resident workers that reproduce within their own colonies. Explaining levels of worker reproduction, and hence the potential of worker selfishness to undermine the evolution of cooperation, will therefore require more than simply a consideration of the kin-selected interests of resident workers. It will also require knowledge of the full set of reproductive options available to workers, including intraspecific social parasitism.     

Fehlende immunogene Wirkung exogenen Insulins bei Hunden nach langsamer Adaptation an Insulin

Summary Subcutaneous injection of exogenous insulin always results in a production of antibodies against insulin. But after a slowly increased dose of insulin (a daily end dose of 3.5–4.2 U/kg) insulin antibodies could not be found in the serum of 2 dogs. This failure of immunogenic action of insulin is discussed as an induction of immunotolerance by the modus of initial antigen application.     

Mutations of the catalytic subunit of RAB3GAP cause Warburg Micro syndrome

Warburg Micro syndrome (WARBM1) is a severe autosomal recessive disorder characterized by developmental abnormalities of the eye and central nervous system and by microgenitalia. We identified homozygous inactivating mutations in RAB3GAP, encoding RAB3 GTPase activating protein, a key regulator of the Rab3 pathway implicated in exocytic release of neurotransmitters and hormones, in 12 families with Micro syndrome. We hypothesize that the underlying pathogenesis of Micro syndrome is a failure of exocytic release of ocular and neurodevelopmental trophic factors.     

Der Einbau von35S in die Kostalknorpel von Meerschweinchen unter Einfluss verschiedener Glucocorticoide

Summary The uptake of³⁵S, in the chondroitin sulfate of the costal cartilage of guinea pigs, is inhibited by cortisone, methyl-prednisolon, triamcinolon, and dexamethason. No inhibition could be seen under the influence of the natural adrenal hormone hydrocortisone and its nearest relation, prednisolon.     

Changes in the distribution of marital age differences in England and Wales, 1963 to 1998

Assumptions about the 'typical' age gap between spouses underlie much social policy (e.g. the five-year difference in men's and women's state pension ages). In order to test the basis for these assumptions, detailed marriage registration statistics were obtained for 1963 and 1998, for England and Wales. Age differences between spouses were calculated and analysed by year, age at marriage and previous marital status. The median age gap hardly changed between 1963 and 1998 but this concealed considerable increase in the proportion of marriages where the man was younger than the woman or--to a lesser extent--where the man was six or more years older.     

SPG20 is mutated in Troyer syndrome,an hereditary spastic paraplegia

Troyer syndrome (TRS) is an autosomal recessive complicated hereditary spastic paraplegia (HSP) that occurs with high frequency in the Old Order Amish. We report mapping of the TRS locus to chromosome 13q12.3 and identify a frameshift mutation in SPG20, encoding spartin. Comparative sequence analysis indicates that spartin shares similarity with molecules involved in endosomal trafficking and with spastin, a molecule implicated in microtubule interaction that is commonly mutated in HSP.     

Phallolysin,ein hochmolekulares toxin ausAmanita phalloides

Summary Phallolysin, a toxic hemolysin of high molecular weight, was isolated from aqueous extracts ofAmanita phalloides. Its properties are discussed.