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111.
The aim of the present study was to assess ultrasonography (US) for the detection of inflammatory and destructive changes in finger and toe joints, tendons, and entheses in patients with psoriasis-associated arthritis (PsA) by comparison with magnetic resonance imaging (MRI), projection radiography (x-ray), and clinical findings. Fifteen patients with PsA, 5 with rheumatoid arthritis (RA), and 5 healthy control persons were examined by means of US, contrast-enhanced MRI, x-ray, and clinical assessment. Each joint of the 2nd–5th finger (metacarpophalangeal joints, proximal interphalangeal [PIP] joints, and distal interphalangeal [DIP] joints) and 1st–5th metatarsophalangeal joints of both hands and feet were assessed with US for the presence of synovitis, bone erosions, bone proliferations, and capsular/extracapsular power Doppler signal (only in the PIP joints). The 2nd–5th flexor and extensor tendons of the fingers were assessed for the presence of insertional changes and tenosynovitis. One hand was assessed by means of MRI for the aforementioned changes. X-rays of both hands and feet were assessed for bone erosions and proliferations. US was repeated in 8 persons by another ultrasonographer. US and MRI were more sensitive to inflammatory and destructive changes than x-ray and clinical examination, and US showed a good interobserver agreement for bone changes (median 96% absolute agreement) and lower interobserver agreement for inflammatory changes (median 92% absolute agreement). A high absolute agreement (85% to 100%) for all destructive changes and a more moderate absolute agreement (73% to 100%) for the inflammatory pathologies were found between US and MRI. US detected a higher frequency of DIP joint changes in the PsA patients compared with RA patients. In particular, bone changes were found exclusively in PsA DIP joints. Furthermore, bone proliferations were more common and tenosynovitis was less frequent in PsA than RA. For other pathologies, no disease-specific pattern was observed. US and MRI have major potential for improved examination of joints, tendons, and entheses in fingers and toes of patients with PsA.  相似文献   
112.

Background

Chronic kidney disease (CKD) is a major health issue for HIV-positive individuals, associated with increased morbidity and mortality. Development and implementation of a risk score model for CKD would allow comparison of the risks and benefits of adding potentially nephrotoxic antiretrovirals to a treatment regimen and would identify those at greatest risk of CKD. The aims of this study were to develop a simple, externally validated, and widely applicable long-term risk score model for CKD in HIV-positive individuals that can guide decision making in clinical practice.

Methods and Findings

A total of 17,954 HIV-positive individuals from the Data Collection on Adverse Events of Anti-HIV Drugs (D:A:D) study with ≥3 estimated glomerular filtration rate (eGFR) values after 1 January 2004 were included. Baseline was defined as the first eGFR > 60 ml/min/1.73 m2 after 1 January 2004; individuals with exposure to tenofovir, atazanavir, atazanavir/ritonavir, lopinavir/ritonavir, other boosted protease inhibitors before baseline were excluded. CKD was defined as confirmed (>3 mo apart) eGFR ≤ 60 ml/min/1.73 m2. Poisson regression was used to develop a risk score, externally validated on two independent cohorts.In the D:A:D study, 641 individuals developed CKD during 103,185 person-years of follow-up (PYFU; incidence 6.2/1,000 PYFU, 95% CI 5.7–6.7; median follow-up 6.1 y, range 0.3–9.1 y). Older age, intravenous drug use, hepatitis C coinfection, lower baseline eGFR, female gender, lower CD4 count nadir, hypertension, diabetes, and cardiovascular disease (CVD) predicted CKD. The adjusted incidence rate ratios of these nine categorical variables were scaled and summed to create the risk score. The median risk score at baseline was −2 (interquartile range –4 to 2). There was a 1:393 chance of developing CKD in the next 5 y in the low risk group (risk score < 0, 33 events), rising to 1:47 and 1:6 in the medium (risk score 0–4, 103 events) and high risk groups (risk score ≥ 5, 505 events), respectively. Number needed to harm (NNTH) at 5 y when starting unboosted atazanavir or lopinavir/ritonavir among those with a low risk score was 1,702 (95% CI 1,166–3,367); NNTH was 202 (95% CI 159–278) and 21 (95% CI 19–23), respectively, for those with a medium and high risk score. NNTH was 739 (95% CI 506–1462), 88 (95% CI 69–121), and 9 (95% CI 8–10) for those with a low, medium, and high risk score, respectively, starting tenofovir, atazanavir/ritonavir, or another boosted protease inhibitor.The Royal Free Hospital Clinic Cohort included 2,548 individuals, of whom 94 individuals developed CKD (3.7%) during 18,376 PYFU (median follow-up 7.4 y, range 0.3–12.7 y). Of 2,013 individuals included from the SMART/ESPRIT control arms, 32 individuals developed CKD (1.6%) during 8,452 PYFU (median follow-up 4.1 y, range 0.6–8.1 y). External validation showed that the risk score predicted well in these cohorts. Limitations of this study included limited data on race and no information on proteinuria.

Conclusions

Both traditional and HIV-related risk factors were predictive of CKD. These factors were used to develop a risk score for CKD in HIV infection, externally validated, that has direct clinical relevance for patients and clinicians to weigh the benefits of certain antiretrovirals against the risk of CKD and to identify those at greatest risk of CKD.  相似文献   
113.
The Biofilm (BF) building capacity of different serotypes of Salmonella enterica derived from the poultry farm environment was investigated. Starting point for the investigation was the question if farm-isolated Salmonella serotypes with high importance for poultry meat and egg production are capable of forming a BF under defined laboratory conditions. Several isolates from different stages of the production cycle were chosen and compared to laboratory grown strains of the same serotype. BF building capacity was analyzed in a 96-well format during a time period of 2?days. Pulse field gel electrophoresis was used to establish a relationship between different isolates. The BF building capacity of a monospecies BF was strongly dependent on the temperature used for incubation. Results indicated further that certain farm isolates were capable of forming BF under laboratory conditions, whereas laboratory grown strains were not. Considerable differences between different field serovars and within one serovar exist. In conclusion, the BF building capacity of poultry-derived isolates is a function of adaptation to their host environment. Thus, the control of BF as a reservoir for Salmonella in the farm environment is of crucial importance for the overall improvement of food safety. Mechanical and substance-based approaches for this control exist in several variations, but overall decontamination success is difficult to achieve and needs to be especially adapted to the farm environment.  相似文献   
114.
Alzheimer??s disease (AD) is a disabling, fatal disease, where animal models potentially can enable investigation of aetiology and treatment. The first litter of G?ttingen minipigs carrying a mutation for human AD was born in 2007, showing transgene expression. In human AD patients, memory impairment is the most striking and consistent feature. The aim of the present study was to examine effects of the APPsw transgene on memory of AD minipigs compared with non-transgenic controls at two ages (1?C2?years) using the spontaneous object recognition test (SORT), which is based on behavioural discrimination of familiar and novel objects. No significant difference between AD minipigs and controls was found when comparing object recognition as a measure of memory. The minipigs did explore the novel object significantly more than the familiar, indicating the expected recognition of the familiar object. Two different inter-phase intervals were used (IPI: 10?C40?min). For both ages, object recognition was evident using 10?min IPI. When using 40?min IPI, object recognition was evident only at age 1?year. Comparing memory of a relatively small group of AD minipigs and controls at two rather young ages using the SORT, we were not able to show memory impairment in APPsw carrying minipigs. Being an age-dependent disease, the transgene is expected to cause AD-like symptoms in this porcine model, and the SORT should be repeated at older ages.  相似文献   
115.
Our aim was to measure whole body energy expenditure after a mixed liquid meal, with and without simultaneous propranolol infusion, in patients with cirrhosis. We also wanted to investigate the effect of propranolol on substrate fluxes and oxygen uptake in the tissues drained by the hepatic vein and azygos vein in the postprandial period in these patients. Whole-body oxygen uptake, hepatic blood flow, hepatic venous pressure gradient and net-hepatic fluxes of oxygen, lactate, glucose, glycerol, and free fatty acids (FFA) were measured in 12 patients with alcoholic cirrhosis before and for 2 h after ingestion of a mixed liquid meal (700 kcal). Half of the patients (n = 6) were randomized to a treatment group receiving intravenous infusion of propranolol in combination with the meal. The meal-induced energy expenditure was significantly lower in patients given propranolol [15.0 +/- 18.9 vs. 67.0 +/- 26.1 kJ/120 min (means +/- SD), P < 0.01]. Meal-induced whole body oxygen uptake was lower in patients receiving propranolol (19.2 +/- 38 vs. 135.7 +/- 61 mmol/120 min, P < 0.01), and the meal-induced increase in splanchnic oxygen uptake was nonexistent when propranolol was administered in combination (-13.2 +/- 34.8 vs. 110.4 +/- 34.8 mmol/120 min, P = 0.04). Postprandially, the propranolol group had a tendency toward a reduced splanchnic glucose output, and the FFA uptake was significantly reduced. Propranolol reduces meal-induced whole body oxygen uptake and energy expenditure as well as splanchnic oxygen uptake. The splanchnic reduction in oxygen consumption can explain almost the entire reduction in whole body oxygen consumption.  相似文献   
116.
Development of molecular tools for the analysis of the plant genetic contribution to rhizobial and mycorrhizal symbiosis has provided major advances in our understanding of plant-microbe interactions, and several key symbiotic genes have been identified and characterized. In order to increase the efficiency of genetic analysis in the model legume Lotus japonicus, we present here a selection of improved genetic tools. The two genetic linkage maps previously developed from an interspecific cross between L. japonicus Gifu and L. filicaulis, and an intraspecific cross between the two ecotypes L. japonicus Gifu and L. japonicus MG-20, were aligned through a set of anchor markers. Regions of linkage groups, where genetic resolution is obtained preferentially using one or the other parental combination, are highlighted. Additional genetic resolution and stabilized mapping populations were obtained in recombinant inbred lines derived by a single seed descent from the two populations. For faster mapping of new loci, a selection of reliable markers spread over the chromosome arms provides a common framework for more efficient identification of new alleles and new symbiotic loci among uncharacterized mutant lines. Combining resources from the Lotus community, map positions of a large collection of symbiotic loci are provided together with alleles and closely linked molecular markers. Altogether, this establishes a common genetic resource for Lotus spp. A web-based version will enable this resource to be curated and updated regularly.  相似文献   
117.
The fungal genus Ulocladium consists mostly of saprotrophic species and can readily be isolated from dead vegetation, rotten wood, paper, textiles and other cellulose containing materials. Thus, they must produce cellulolytic and hemicellulolytic enzymes. In this study fifty Ulocladium strains from ten different species were tested for enzyme activities on 14 different azurine-cross-linked (AZCL) substrates and analyzed by multivariate analysis. The tested strains of Ulocladium were found to produce a broad enzyme profile. Most species in Ulocladium were able to produced high amounts of enzymes that degraded amylose, arabinoxylan, β-glucan, cellulose and xylan; however, variations between species as well as between individual strains in each species were seen. Overall, the enzyme profiles were found to be species specific, but also source of isolation impacted the enzymes produced. The results suggest that species identity as well as isolation source must be considered when screening microorganisms for enzymes.  相似文献   
118.
β-Microseminoprotein (MSP), a 10 kDa seminal plasma protein, forms a tight complex with cysteine-rich secretory protein 3 (CRISP-3) from granulocytes. The 3D structure of human MSP has been determined but there is as yet no 3D structure for CRISP-3. We have now studied the complex between human MSP and CRISP-3 with multidimensional NMR. 15N-HSQC spectra show substantial differences between free and complexed hMSP. Using several 3D-NMR spectra of triply labeled hMSP in complex with a recombinant N-terminal domain of CRISP-3, most of the backbone of hMSP could be assigned. The data show that only one side of hMSP, comprising β-strands 1, 4, 5, and 8 are affected by the complex formation, indicating that β-strands 1 and 8 form the main binding surface. Based on this we present a tentative structure for the hMSP-CRISP-3 complex using the known crystal structure of triflin as a model of CRISP-3.  相似文献   
119.
Extensive angiogenesis, formation of new capillaries from pre-existing blood vessels, is an important feature of malignant glioma. Several antiangiogenic drugs targeting vascular endothelial growth factor (VEGF) or its receptors are currently in clinical trials as therapy for high-grade glioma and bevacizumab was recently approved by the FDA for treatment of recurrent glioblastoma. However, the modest efficacy of these drugs and emerging problems with anti-VEGF treatment resistance welcome the development of alternative antiangiogenic therapies. One potential candidate is histidine-rich glycoprotein (HRG), a plasma protein with antiangiogenic properties that can inhibit endothelial cell adhesion and migration. We have used the RCAS/TV-A mouse model for gliomas to investigate the effect of HRG on brain tumor development. Tumors were induced with platelet-derived growth factor-B (PDGF-B), in the presence or absence of HRG. We found that HRG had little effect on tumor incidence but could significantly inhibit the development of malignant glioma and completely prevent the occurrence of grade IV tumors (glioblastoma).  相似文献   
120.
DNA mutations are circumvented by dedicated specialized excision repair systems, such as the base excision repair (BER), nucleotide excision repair (NER), and mismatch repair (MMR) pathways. Although the individual repair pathways have distinct roles in suppressing changes in the nuclear DNA, it is evident that proteins from the different DNA repair pathways interact [Y. Wang, D. Cortez, P. Yazdi, N. Neff, S.J. Elledge, J. Qin, BASC, a super complex of BRCA1-associated proteins involved in the recognition and repair of aberrant DNA structures, Genes Dev. 14 (2000) 927–939; M. Christmann, M.T. Tomicic, W.P. Roos, B. Kaina, Mechanisms of human DNA repair: an update, Toxicology 193 (2003) 3–34; N.B. Larsen, M. Rasmussen, L.J. Rasmussen, Nuclear and mitochondrial DNA repair: similar pathways? Mitochondrion 5 (2005) 89–108]. Protein interactions are not only important for function, but also for regulation of nuclear import that is necessary for proper localization of the repair proteins. This review summarizes the current knowledge on nuclear import mechanisms of DNA excision repair proteins and provides a model that categorizes the import by different mechanisms, including classical nuclear import, co-import of proteins, and alternative transport pathways. Most excision repair proteins appear to contain classical NLS sequences directing their nuclear import, however, additional import mechanisms add alternative regulatory levels to protein import, indirectly affecting protein function. Protein co-import appears to be a mechanism employed by the composite repair systems NER and MMR to enhance and regulate nuclear accumulation of repair proteins thereby ensuring faithful DNA repair.  相似文献   
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