72 research outputs found
Distinct physiological and behavioural functions for parental alleles of imprinted Grb10
Imprinted genes, defined by their preferential expression of a single parental allele, represent a subset of the mammalian genome and often have key roles in embryonic development1, but also postnatal functions including energy homeostasis2 and behaviour3, 4. When the two parental alleles are unequally represented within a social group (when there is sex bias in dispersal and/or variance in reproductive success)5, 6, imprinted genes may evolve to modulate social behaviour, although so far no such instance is known. Predominantly expressed from the maternal allele during embryogenesis, Grb10 encodes an intracellular adaptor protein that can interact with several receptor tyrosine kinases and downstream signalling molecules7. Here we demonstrate that within the brain Grb10 is expressed from the paternal allele from fetal life into adulthood and that ablation of this expression engenders increased social dominance specifically among other aspects of social behaviour, a finding supported by the observed increase in allogrooming by paternal Grb10-deficient animals. Grb10 is, therefore, the first example of an imprinted gene that regulates social behaviour. It is also currently alone in exhibiting imprinted expression from each of the parental alleles in a tissue-specific manner, as loss of the peripherally expressed maternal allele leads to significant fetal and placental overgrowth. Thus Grb10 is, so far, a unique imprinted gene, able to influence distinct physiological processes, fetal growth and adult behaviour, owing to actions of the two parental alleles in different tissues
Cell entry of a host targeting protein of oomycetes requires gp96
This work is supported by the [European Communityβs] Seventh Framework Programme [FP7/2007β2013] under grant agreement no. [238550] (L.L., J.D.-U., C.J.S., P.v.W.); BBSRC [BBE007120/1, BB/J018333/1 and BB/G012075/1] (F.T., I.d.B., C.J.S., S.W., P.v.W.); Newton Global Partnership Award [BB/N005058/1] (F.T., P.v.W.), the University of Aberdeen (A.D.T., T.R., C.J.S., P.v.W.) and Deutsche Forschungsgemeinschaft [CRC1093] (P.B., T.S.). We would like to acknowledge the Ministry of Higher Education Malaysia for funding INA. We would like to thank Brian Haas for his bioinformatics support. We would like to acknowledge Neil Gow and Johannes van den Boom for critical reading of the manuscript. We would like to acknowledge Svetlana Rezinciuc for technical help with pH-studies.Peer reviewedPublisher PD
Why do health workers in rural Tanzania prefer public sector employment?
Severe shortages of qualified health workers and geographical imbalances in the workforce in many low-income countries require the national health sector management to closely monitor and address issues related to the distribution of health workers across various types of health facilities. This article discusses health workers' preferences for workplace and their perceptions and experiences of the differences in working conditions in the public health sector versus the church-run health facilities in Tanzania. The broader aim is to generate knowledge that can add to debates on health sector management in low-income contexts. The study has a qualitative study design to elicit in-depth information on health workers' preferences for workplace. The data comprise ten focus group discussions (FGDs) and 29 in-depth interviews (IDIs) with auxiliary staff, nursing staff, clinicians and administrators in the public health sector and in a large church-run hospital in a rural district in Tanzania. The study has an ethnographic backdrop based on earlier long-term fieldwork in Tanzania. The study found a clear preference for public sector employment. This was associated with health worker rights and access to various benefits offered to health workers in government service, particularly the favourable pension schemes providing economic security in old age. Health workers acknowledged that church-run hospitals generally were better equipped and provided better quality patient care, but these concerns tended to be outweighed by the financial assets of public sector employment. In addition to the sector specific differences, family concerns emerged as important in decisions on workplace. The preference for public sector employment among health workers shown in this study seems to be associated primarily with the favourable pension scheme. The overall shortage of health workers and the distribution between health facilities is a challenge in a resource constrained health system where church-run health facilities are vital in the provision of health care in rural areas and where patients tend to prefer these services. In order to ensure equity in distribution of qualified health workers in Tanzania, a national regulation and legislation of the pension schemes is required
The fallacy of placing confidence in confidence intervals
Interval estimates β estimates of parameters that include an allowance for sampling uncertainty β have long been touted as a key component of statistical analyses. There are several kinds of interval estimates, but the most popular are confidence intervals (CIs): intervals that contain the true parameter value in some known proportion of repeated samples, on average. The width of confidence intervals is thought to index the precision of an estimate; CIs are thought to be a guide to which parameter values are plausible or reasonable; and the confidence coefficient of the interval (e.g., 95 %) is thought to index the plausibility that the true parameter is included in the interval. We show in a number of examples that CIs do not necessarily have any of these properties, and can lead to unjustified or arbitrary inferences. For this reason, we caution against relying upon confidence interval theory to justify interval estimates, and suggest that other theories of interval estimation should be used instead
Resolution of inflammation: a new therapeutic frontier
Dysregulated inflammation is a central pathological process in diverse disease states. Traditionally, therapeutic approaches have sought to modulate the pro- or anti-inflammatory limbs of inflammation, with mixed success. However, insight into the pathways by which inflammation is resolved has highlighted novel opportunities to pharmacologically manipulate these processes β a strategy that might represent a complementary (and perhaps even superior) therapeutic approach. This Review discusses the state of the art in the biology of resolution of inflammation, highlighting the opportunities and challenges for translational research in this field
Evidence for a Novel Marine Harmful Algal Bloom: Cyanotoxin (Microcystin) Transfer from Land to Sea Otters
βSuper-bloomsβ of cyanobacteria that produce potent and environmentally persistent biotoxins (microcystins) are an emerging global health issue in freshwater habitats. Monitoring of the marine environment for secondary impacts has been minimal, although microcystin-contaminated freshwater is known to be entering marine ecosystems. Here we confirm deaths of marine mammals from microcystin intoxication and provide evidence implicating land-sea flow with trophic transfer through marine invertebrates as the most likely route of exposure. This hypothesis was evaluated through environmental detection of potential freshwater and marine microcystin sources, sea otter necropsy with biochemical analysis of tissues and evaluation of bioaccumulation of freshwater microcystins by marine invertebrates. Ocean discharge of freshwater microcystins was confirmed for three nutrient-impaired rivers flowing into the Monterey Bay National Marine Sanctuary, and microcystin concentrations up to 2,900 ppm (2.9 million ppb) were detected in a freshwater lake and downstream tributaries to within 1 km of the ocean. Deaths of 21 southern sea otters, a federally listed threatened species, were linked to microcystin intoxication. Finally, farmed and free-living marine clams, mussels and oysters of species that are often consumed by sea otters and humans exhibited significant biomagnification (to 107 times ambient water levels) and slow depuration of freshwater cyanotoxins, suggesting a potentially serious environmental and public health threat that extends from the lowest trophic levels of nutrient-impaired freshwater habitat to apex marine predators. Microcystin-poisoned sea otters were commonly recovered near river mouths and harbors and contaminated marine bivalves were implicated as the most likely source of this potent hepatotoxin for wild otters. This is the first report of deaths of marine mammals due to cyanotoxins and confirms the existence of a novel class of marine βharmful algal bloomβ in the Pacific coastal environment; that of hepatotoxic shellfish poisoning (HSP), suggesting that animals and humans are at risk from microcystin poisoning when consuming shellfish harvested at the land-sea interface
Complexity of the Mycoplasma fermentans M64 Genome and Metabolic Essentiality and Diversity among Mycoplasmas
Recently, the genomes of two Mycoplasma fermentans strains, namely M64 and JER, have been completely sequenced. Gross comparison indicated that the genome of M64 is significantly bigger than the other strain and the difference is mainly contributed by the repetitive sequences including seven families of simple and complex transposable elements ranging from 973 to 23,778 bps. Analysis of these repeats resulted in the identification of a new distinct family of Integrative Conjugal Elements of M. fermentans, designated as ICEF-III. Using the concept of βreaction connectivityβ, the metabolic capabilities in M. fermentans manifested by the complete and partial connected biomodules were revealed. A comparison of the reported M. pulmonis, M. arthritidis, M. genitalium, B. subtilis, and E. coli essential genes and the genes predicted from the M64 genome indicated that more than 73% of the Mycoplasmas essential genes are preserved in M. fermentans. Further examination of the highly and partly connected reactions by a novel combinatorial phylogenetic tree, metabolic network, and essential gene analysis indicated that some of the pathways (e.g. purine and pyrimidine metabolisms) with partial connected reactions may be important for the conversions of intermediate metabolites. Taken together, in light of systems and network analyses, the diversity among the Mycoplasma species was manifested on the variations of their limited metabolic abilities during evolution
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