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Henriksen TF Hölmich LR Friis S McLaughlin JK Fryzek JP Pernille Høyer A Kjøller K Olsen JH 《Plastic and reconstructive surgery》2003,111(7):2182-9; discussion 2190-1
Although numerous epidemiologic studies have examined the long-term safety of silicone breast implants during the past decade, there is a relative lack of surveillance data on short-term health effects and complications following cosmetic surgery of the breast. The Danish Registry for Plastic Surgery of the Breast, established in May of 1999, provides plastic surgeons with a nationwide system for the collection of preoperative, perioperative, and postoperative data on women undergoing breast implantation, breast reduction, or mastopexy. The purpose of the Registry is to examine short-term and, eventually, long-term local complications and possible health effects, and to contribute to an ongoing evaluation of surgical results and surveillance of the products. Furthermore, the Registry will allow the identification of new areas for research into cosmetic and reconstructive breast surgery. Women accepting registration in the Danish Registry for Plastic Surgery of the Breast complete a self-administered questionnaire focusing on medical history and demographic and behavioral factors. Preoperative blood samples are drawn for storage. Surgical data, postoperative results, and complications are registered following surgery and at postoperative visits. Currently, registration has been initiated at 24 private and public clinics, representing more than 80 percent of the plastic surgery clinics in Denmark. As of November of 2001, a total of 1472 women with breast implants and 560 women with breast reduction were included in the Registry. These figures are expected to increase annually by 1000 women undergoing breast implantation and 500 women undergoing breast reduction or mastopexy. The authors present their experience of establishing the first nationwide comprehensive clinical-epidemiologic database and biological bank for cosmetic and reconstructive surgery procedures. 相似文献
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We previously identified the Fas-associated factor FAF1 as an in vitro substrate of protein kinase CK2 and determined Ser289 and Ser291 as phosphorylation sites. Here we demonstrate that these two serine residues are the only sites phosphorylated by CK2 in vitro, and that at least one site is phosphorylated in vivo. Furthermore, we analyzed putative physiological functions of FAF1 phosphorylation. The ability of FAF1 to potentiate Fas-induced apoptosis is not influenced by the FAF1 phosphorylation status; however, the nuclear import of a phosphorylation-deficient FAF1 mutant was delayed in comparison to wild-type FAF1. 相似文献
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Petra Griekspoor Frances M. Colles Noel D. McCarthy Philip M. Hansbro Chris Ashhurst‐Smith Björn Olsen Dennis Hasselquist Martin C. J. Maiden Jonas Waldenström 《Molecular ecology》2013,22(5):1463-1472
Zoonotic pathogens often infect several animal species, and gene flow among populations infecting different host species may affect the biological traits of the pathogen including host specificity, transmissibility and virulence. The bacterium Campylobacter jejuni is a widespread zoonotic multihost pathogen, which frequently causes gastroenteritis in humans. Poultry products are important transmission vehicles to humans, but the bacterium is common in other domestic and wild animals, particularly birds, which are a potential infection source. Population genetic studies of C. jejuni have mainly investigated isolates from humans and domestic animals, so to assess C. jejuni population structure more broadly and investigate host adaptation, 928 wild bird isolates from Europe and Australia were genotyped by multilocus sequencing and compared to the genotypes recovered from 1366 domestic animal and human isolates. Campylobacter jejuni populations from different wild bird species were distinct from each other and from those from domestic animals and humans, and the host species of wild bird was the major determinant of C. jejuni genotype, while geographic origin was of little importance. By comparison, C. jejuni differentiation was restricted between more phylogenetically diverse farm animals, indicating that domesticated animals may represent a novel niche for C. jejuni and thereby driving the evolution of those bacteria as they exploit this niche. Human disease is dominated by isolates from this novel domesticated animal niche. 相似文献
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Cold-Sensitive Pseudomonas RNA Polymerase I. Characterization of the Host Dependent Cold-Sensitive Restriction of Phage CB3 总被引:1,自引:2,他引:1 下载免费PDF全文
Analysis of bacteriophage CB3 infection of Pseudomonas aeruginosa strain PAT2 establishes that phage induced changes in net macromolecular synthesis are absent at nonpermissive phage growth temperatures (32 C). Alterations which are evident in the PAT2 strain at 37 C or in the fully permissive strain, PAO1C, at either warm or cold temperatures do not occur in PAT2 at low temperatures. CB3 DNA synthesis and the degradation of host DNA to approximately 78S components occur at 37 C, but are absent in PAT2 at 20 C. Nevertheless, attachment of phage DNA to host cytoplasmic material occurs under permissive and nonpermissive conditions. This binding of phage DNA at 20 C is identical in nature to phage DNA bound at 37 C. Thus, the conditional cold-sensitive PAT2 host function in the growth of CB3 is expressed subsequent to membrane binding of the infecting genomes but prior to the onset of the initiation of CB3 DNA synthesis, the inhibition of host DNA synthesis, and the transient depression in RNA synthesis which occurs in permissive cells. 相似文献
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Sørensen M Munk OL Mortensen FV Olsen AK Bender D Bass L Keiding S 《American journal of physiology. Gastrointestinal and liver physiology》2008,295(1):G27-G36
Metabolism of galactose is a specialized liver function. The purpose of this PET study was to use the galactose analog 2-[(18)F]fluoro-2-deoxygalactose (FDGal) to investigate hepatic uptake and metabolism of galactose in vivo. FDGal kinetics was studied in 10 anesthetized pigs at blood concentrations of nonradioactive galactose yielding approximately first-order kinetics (tracer only; n = 4), intermediate kinetics (0.5-0.6 mmol galactose/l blood; n = 2), and near-saturation kinetics (>3 mmol galactose/l blood; n = 4). All animals underwent liver C15O PET (blood volume) and FDGal PET (galactose kinetics) with arterial and portal venous blood sampling. Flow rates in the hepatic artery and the portal vein were measured by ultrasound transit-time flowmeters. The hepatic uptake and net metabolic clearance of FDGal were quantified by nonlinear and linear regression analyses. The initial extraction fraction of FDGal from blood-to-hepatocyte was unity in all pigs. Hepatic net metabolic clearance of FDGal, K(FDGal), was 332-481 ml blood.min(-1).l(-1) tissue in experiments with approximately first-order kinetics and 15.2-21.8 ml blood.min(-1).l(-1) tissue in experiments with near-saturation kinetics. Maximal hepatic removal rates of galactose were on average 600 micromol.min(-1).l(-1) tissue (range 412-702), which was in agreement with other studies. There was no significant difference between K(FDGal) calculated with use of the dual tracer input (Kdual(FDGal)) or the single arterial input (Karterial(FDGal)). In conclusion, hepatic galactose kinetics can be quantified with the galactose analog FDGal. At near-saturated kinetics, the maximal hepatic removal rate of galactose can be calculated from the net metabolic clearance of FDGal and the blood concentration of galactose. 相似文献
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The transmembrane, bacteriochlorophyll-binding region of a bacterial light-harvesting complex, (LH2-alpha from the photosynthetic bacterium Rhodobacter sphaeroides) was redesigned and overexpressed in a mutant of Rb. sphaeroides lacking LH2. Bacteriochlorophyll served as internal probe for the fitness of this new region for the assembly and energy transfer function of the LH2 complex. The ability to absorb and transfer light energy is practically undisturbed by the exchange of the transmembrane segment, valine -7 to threonine +6, of LH2-alpha with a 14 residue Ala-Leu sequence. This stretch makes up the residues of the transmembrane helix that are in close contact (< or =4.5 A) with the bacteriochlorophyll molecules that are coordinated through His of both the alpha and beta-subunits. In this Ala-Leu stretch, neither alpha-His0, which binds the bacteriochlorophyll, nor the adjacent alpha-Ile-1, were replaced. Novel LH2 complexes composed of LH2-alpha with a model transmembrane sequence and a normal LH2-beta are assembled in vivo into a complex, the biochemical and spectroscopic properties of which closely resemble the native one. In contrast, the additional insertion of four residues just outside the C-terminal end of the model transmembrane helix leads to complete loss of functional antenna complex. The results suggest that light energy can be harvested and transferred efficiently by bacteriochlorophyll molecules attached to only few key residues distributed over the polypeptide, while residues at the bacteriochlorophyll-helix interface seem to be largely dispensable for the functional assembly of this membrane protein complex. This novel antenna with a simplified transmembrane domain and a built-in probe for assembly and function provides a powerful model system for investigation of the factors that contribute to the assembly of chromophores in membrane-embedded proteins. 相似文献