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Mattsson C Rask E Carlström K Andersson J Eliasson M Ahrén B Söderberg S Olsson T 《Obesity (Silver Spring, Md.)》2007,15(4):887-894
Objective: Reduction of cortisone to cortisol is mediated by 11β‐hydroxysteroid dehydrogenase type 1 (11βHSD1), a putative key enzyme in obesity‐related complications. Experimental studies suggest that adipokines, notably leptin and tumor necrosis factor‐α (TNF‐α), are of importance for 11βHSD1 activity. We hypothesized that the regulation of hepatic preceptor glucocorticoid metabolism is gender‐specific and associated with circulating levels of leptin and TNF‐α receptors and/or sex hormones. Research Methods and Procedures: A total of 34 males and 38 women (14 premenopausal and 22 postmenopausal) underwent physical examination and fasting blood sampling. Insulin sensitivity was tested by euglycemic hyperinsulinemic clamps, and hepatic 11βHSD1 enzyme activity was estimated by the conversion of orally‐ingested cortisone to cortisol. Results: Hepatic 11βHSD1 activity was negatively associated with leptin and soluble TNF (sTNF) r1 and sTNFr2 in males. These correlations remained significant after adjustment for age and insulin sensitivity, and for sTNF‐α receptors also after adjustment of BMI and waist circumference. In contrast, 11β reduction of cortisone was positively associated to leptin in females after adjustment for BMI and waist circumference. Discussion: Hepatic 11β reduction shows different links to circulating adipocyte‐derived hormones in males and females. This emphasizes the need for further studies on tissue‐specific regulation of 11βHSD1 in both genders. 相似文献
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Eleven novel polymorphic microsatellite loci developed from a microsatellite enriched genomic library, are presented for the
Australian tree frog Litoria peronii. We screened 29 individuals from a single population and detected high levels of polymorphism for all 11 loci with the number
of alleles/locus ranging from 9 to 24. Values of expected and observed heterozygosities ranged from 0.789–0.955 and 0.207–1.00,
respectively. These microsatellite markers should prove useful in determining levels of genetic diversity, measuring gene
flow and migration, assigning individuals to their most likely population of origin, and in the assignment of paternity. 相似文献
76.
Chêne A Donati D Guerreiro-Cacais AO Levitsky V Chen Q Falk KI Orem J Kironde F Wahlgren M Bejarano MT 《PLoS pathogens》2007,3(6):e80
Although malaria and Epstein-Barr (EBV) infection are recognized cofactors in the genesis of endemic Burkitt lymphoma (BL), their relative contribution is not understood. BL, the most common paediatric cancer in equatorial Africa, is a high-grade B cell lymphoma characterized by c-myc translocation. EBV is a ubiquitous B lymphotropic virus that persists in a latent state after primary infection, and in Africa, most children have sero-converted by 3 y of age. Malaria infection profoundly affects the B cell compartment, inducing polyclonal activation and hyper-gammaglobulinemia. We recently identified the cystein-rich inter-domain region 1alpha (CIDR1alpha) of the Plasmodium falciparum membrane protein 1 as a polyclonal B cell activator that preferentially activates the memory compartment, where EBV is known to persist. Here, we have addressed the mechanisms of interaction between CIDR1alpha and EBV in the context of B cells. We show that CIDR1alpha binds to the EBV-positive B cell line Akata and increases the number of cells switching to the viral lytic cycle as measured by green fluorescent protein (GFP) expression driven by a lytic promoter. The virus production in CIDR1alpha-exposed cultures was directly proportional to the number of GFP-positive Akata cells (lytic EBV) and to the increased expression of the EBV lytic promoter BZLF1. Furthermore, CIDR1alpha stimulated the production of EBV in peripheral blood mononuclear cells derived from healthy donors and children with BL. Our results suggest that P. falciparum antigens such as CIDR1alpha can directly induce EBV reactivation during malaria infection that may increase the risk of BL development for children living in malaria-endemic areas. To our knowledge, this is the first report to show that a microbial protein can drive a latently infected B cell into EBV replication. 相似文献
77.
Martin Qvarnstrm Stavros Anagnostakis Anders Lindskog Udo Scheer Vivi Vajda Bo W. Rasmussen Johan Lindgren Mats E. Eriksson 《Lethaia: An International Journal of Palaeontology and Stratigraphy》2019,52(4):550-569
A total of 462 coprolites from three localities exposing Upper Cretaceous deposits in the Münster Basin, northwestern Germany, have been subjected to an array of analytical techniques, with the aim of elucidating ancient trophic structures and predator–prey interactions. The phosphatic composition, frequent bone inclusions, size and morphology collectively suggest that most, if not all, coprolites were produced by carnivorous (predatory or scavenging) vertebrates. The bone inclusions further indicate that the coprolite producers preyed principally upon fish. Putative host animals include bony fish, sharks and marine reptiles – all of which have been previously recorded from the Münster Basin. The presence of borings and other traces on several coprolites implies handling by coprophagous organisms. Remains of epibionts are also common, most of which have been identified as the encrusting bivalve Atreta. Palynological analyses of both the coprolites and host rocks reveal a sparse assemblage dominated by typical Late Cretaceous dinoflagellates, and with sub‐ordinate fern spores, conifer pollen grains and angiosperm pollen grains. The dinoflagellate key taxon Exochosphaeridium cenomaniense corroborates a Cenomanian age for the Plenus Marl, from which most studied coprolites derive. The findings of this study highlight the potential of a multi‐proxy approach when it comes to unravelling the origin, composition and importance of coprolites in palaeoecosystem analyses. 相似文献
78.
Abstract This investigation describes the detection of a component in Escherichia coli capable of binding a large proportion of human antibody variable domains including otherwise highly monospecific antibodies induced by an in vivo antibody response. This interaction is of low affinity, but cross-linking of IgG molecules by e.g. anti-immunoglobulin preparations, provides a sufficient degree of multivalency to promote a high avidity interaction. This binding which occurs both with κ and λ light chain-containing antibodies, appears to involve the variable region of human antibodies making it a superantigen-like activity. This is proposed based on the facts that: (i) different human antibodies of IgG1 isotype appear to bind to different extents suggesting that variable domain differences determine the binding activity; and (ii) addition of soluble antigen abrogates the interaction with the E. coli -derived molecule. Future studies of the nature and possible in vivo consequences of these interactions are warranted since any superantigen activity associated with this binding might affect the human immune response occurring as a consequence of E. coli infections. 相似文献
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Ko Y Kobbe B Nicolae C Miosge N Paulsson M Wagener R Aszódi A 《Molecular and cellular biology》2004,24(4):1691-1699
Matrilin-3 belongs to the matrilin family of extracellular matrix (ECM) proteins and is primarily expressed in cartilage. Mutations in the gene encoding human matrilin-3 (MATN-3) lead to autosomal dominant skeletal disorders, such as multiple epiphyseal dysplasia (MED), which is characterized by short stature and early-onset osteoarthritis, and bilateral hereditary microepiphyseal dysplasia, a variant form of MED characterized by pain in the hip and knee joints. To assess the function of matrilin-3 during skeletal development, we have generated Matn-3 null mice. Homozygous mutant mice appear normal, are fertile, and show no obvious skeletal malformations. Histological and ultrastructural analyses reveal endochondral bone formation indistinguishable from that of wild-type animals. Northern blot, immunohistochemical, and biochemical analyses indicated no compensatory upregulation of any other member of the matrilin family. Altogether, our findings suggest functional redundancy among matrilins and demonstrate that the phenotypes of MED disorders are not caused by the absence of matrilin-3 in cartilage ECM. 相似文献