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81.

Objective

The aim of the study was to examine the effectiveness of an intensive inpatient three-week multimodal therapy. We focused especially on the impact on the multimodal therapy outcome of the pre-admission number of treatment types patients had received and of medical specialist groups patients had consulted.

Methods

155 patients with chronic low back pain and indication for multimodal therapy were evaluated with respect to pain intensity, depression, anxiety, well-being, and pre-admission health care utilization. In our controlled clinical trial we compared N = 66 patients on the waiting list with N = 89 patients who received immediate treatment. The waiting list patients likewise attended multimodal therapy after the waiting period. Longitudinal post-treatment data for both were collected at three- and twelve-month follow-ups. The impact of pre-admission health care utilization on multimodal therapy outcome (post) was analysed by structural equation model.

Results

Compared to the control group, multimodal therapy patients’ pain intensity and psychological variables were significantly reduced. Longitudinal effects with respect to pre-measures were significant at three-month follow-up for pain intensity (ES = -0.48), well-being (ES = 0.78), anxiety (ES = -0.33), and depression (ES = -0.30). Effect sizes at twelve-month follow-up were small for anxiety (ES = -0.22), and moderate for general well-being (ES = 0.61). Structural equation model revealed that a higher number of pre-admission treatment types was associated with poorer post-treatment outcomes in pain intensity, well-being, and depression.

Conclusion

Multimodal therapy proved to be effective with regard to improvements in pain intensity, depression, anxiety, and well-being. The association between treatment effect and number of pre-admission pain treatment types suggests that patients would benefit more from attending multimodal therapy in an earlier stage of health care.  相似文献   
82.

Objective

We investigated the association between metabolic factors and End-Stage Renal Disease (ESRD) and quantified the magnitude of their influence dependent on sex and time of exposure up to 20 years.

Material and Methods

A prospective cohort study was conducted to determine risk factors for the development of ESRD. From 1988 to 2005 185,341 persons (53.9% women) participated in the “Vorarlberg Health Monitoring and Promotion Programme” (VHM&PP). Data on body mass index (BMI), fasting blood glucose (FBG), systolic (BPsys) and diastolic (BPdia) blood pressure, total cholesterol (TC), triglycerides (TG), gamma-glutamyltransferase (GGT) and smoking status were collected. Data of the population-based VHM&PP were merged with the Austrian Dialysis and Transplant Registry. Cox proportional hazards models were applied to calculate hazard ratios (HRs) for ESRD, stratified by sex and 5-year time intervals.

Results

During a mean follow-up of 17.5 years 403 patients (39.1% women) developed ESRD. Significant risk factors were: BMI (per 1 kg/m2) HR 1.04 (95% CI 1.01–1.06), FBG (per 1 mmol/L) HR 1.09 (1.05–1.12), BPsys (per 5 mmHg) HR 1.10 (1.07–1.14), BPdia (per 5 mmHg) HR 1.09 (1.03–1.15), TG (per 1 mmol/L) HR 1.07 (1.02–1.13), TC (per 1 mmol/L) HR 1.22 (1.13–1.32). We observed a sex-specific risk pattern with an increased ESRD risk for men for increasing TG and smoking, and for women for increasing BMI and GGT. In time interval analyses BPsys and TC were associated with early ESRD onset, whereas BMI, FBG, BPdia and GGT were associated with later onset.

Conclusions

Anthropometric and metabolic factors are differentially associated with the long-term risk for ESRD in a sex- and time-dependent manner. Consideration of these patterns in preventive and therapeutic strategies could have an impact on ESRD incidence.  相似文献   
83.
DNA analysis from carrion flies (iDNA analysis) has recently been promoted as a powerful tool for cost‐ and time‐efficient monitoring of wildlife. While originally applied to identify any mammalian species present in an area, it should also allow for targeted detection of species and individuals. Using carrion flies captured in the Taï National Park, Côte d'Ivoire, we assessed this possibility by (i) screening carrion fly DNA extracts with nonspecific and species‐specific PCR systems, respectively, targeting mitochondrial DNA (mtDNA) fragments of any mammal or of Jentink's duiker (Cephalophus jentinki), three colobine monkeys (subfamily Colobinae) and sooty mangabey (Cercocebus atys); and (ii) genotyping carrion fly extracts containing sooty mangabey mtDNA. In comparison with the nonspecific PCR assay, the use of specific PCRs increased the frequency of detection of target species up to threefold. Detection rates partially reflected relative abundances of target species in the area. Amplification of seven microsatellite loci from carrion flies positive for sooty mangabey mtDNA yielded an average PCR success of 46%, showing that the identification of individuals is, to some extent, possible. Regression analysis of microsatellite PCR success and mtDNA concentration revealed that, among all carrion flies analysed for this study, 1% contained amounts of mammal mtDNA sufficient to attempt genotyping with potentially high success. We conclude that carrion fly‐derived DNA analysis represents a promising tool for targeted monitoring of mammals in their natural habitat.  相似文献   
84.
Chlamydia trachomatis is an obligate intracellular pathogen responsible for loss of eyesight through trachoma and for millions of cases annually of sexually transmitted diseases. The bacteria develop within a membrane-bounded inclusion. They lack enzymes for several biosynthetic pathways, including those to make some phospholipids, and exploit their host to compensate. Three-dimensional fluorescence microscopy demonstrates that small organelles of the host, peroxisomes, are translocated into the Chlamydia inclusion and are found adjacent to the bacteria. In cells deficient for peroxisome biogenesis the bacteria are able to multiply and give rise to infectious progeny, demonstrating that peroxisomes are not essential for bacterial development in vitro. Mass spectrometry-based lipidomics reveal the presence in C. trachomatis of plasmalogens, ether phospholipids whose synthesis begins in peroxisomes and have never been described in aerobic bacteria before. Some of the bacterial plasmalogens are novel structures containing bacteria-specific odd-chain fatty acids; they are not made in uninfected cells nor in peroxisome-deficient cells. Their biosynthesis is thus accomplished by the metabolic collaboration of peroxisomes and bacteria.  相似文献   
85.
Worldwide increases in fluvial fine sediment are a threat to aquatic animal health. Fluvial fine sediment is always a mixture of particles whose mineralogical composition differs depending on the sediment source and catchment area geology. Nonetheless, whether particle impact in aquatic organisms differs between mineral species remains to be investigated. This study applied an in vitro approach to evaluate cytotoxicity and uptake of four common fluvial mineral particles (quartz, feldspar, mica, and kaolin; concentrations: 10, 50, 250 mg L−1) in the rainbow trout epithelial gill cell line RTgill-W1. Cells were exposed for 24, 48, 72, and 96 h. Cytotoxicity assays for cell membrane integrity (propidium iodide assay), oxidative stress (H2DCF-DA assay), and metabolic activity (MTT assay) were applied. These assays were complemented with cell counts and transmission electron microscopy. Regardless of mineral species, particles ≤2 µm in diameter were taken up by the cells, suggesting that particles of all mineral species came into contact and interacted with the cells. Not all particles, however, caused strong cytotoxicity: Among all assays the tectosilicates quartz and feldspar caused sporadic maximum changes of 0.8–1.2-fold compared to controls. In contrast, cytotoxicity of the clay particles was distinctly stronger and even differed between the two particle types: mica induced concentration-dependent increases in free radicals, with consistent 1.6–1.8-fold-changes at the 250 mg L−1 concentration, and a dilated endoplasmic reticulum. Kaolin caused concentration-dependent increases in cell membrane damage, with consistent 1.3–1.6-fold increases at the 250 mg L−1 concentration. All effects occurred in the presence or absence of 10% fetal bovine serum. Cell numbers per se were marginally affected. Results indicate that (i.) natural mineral particles can be cytotoxic to gill epithelial cells, (ii.) their cytotoxic potential differs between mineral species, with clay particles being more cytotoxic, and (iii.) some clays might induce effects comparable to engineered nanoparticles.  相似文献   
86.
87.
Xanthomonas translucens pv. graminis (Xtg) is a gammaproteobacterium that causes bacterial wilt on a wide range of forage grasses. To gain insight into the host–pathogen interaction and to identify the virulence factors of Xtg, we compared a draft genome sequence of one isolate (Xtg29) with other Xanthomonas spp. with sequenced genomes. The type III secretion system (T3SS) encoding a protein transport system for type III effector (T3E) proteins represents one of the most important virulence factors of Xanthomonas spp. In contrast with other Xanthomonas spp. assigned to clade 1 on the basis of phylogenetic analyses, we identified an hrp (hypersensitive response and pathogenicity) gene cluster encoding T3SS components and a representative set of 35 genes encoding putative T3Es in the genome of Xtg29. The T3SS was shown to be divergent from the hrp gene clusters of other sequenced Xanthomonas spp. Xtg mutants deficient in T3SS regulating and structural genes were constructed to clarify the role of the T3SS in forage grass colonization. Italian ryegrass infection with these mutants led to significantly reduced symptoms (P < 0.05) relative to plants infected with the wild‐type strain. This showed that the T3SS is required for symptom evocation. In planta multiplication of the T3SS mutants was not impaired significantly relative to the wild‐type, indicating that the T3SS is not required for survival until 14 days post‐infection. This study represents the first major step to understanding the bacterial colonization strategies deployed by Xtg and may assist in the identification of resistance (R) genes in forage grasses.  相似文献   
88.
A highly selfing breeding system affects gene flow, which may have consequences for patterns of genetic variation and differentiation on both the population and species level. Feather grasses (Stipa spp.) are dominant elements of Eurasian steppes that persist in Central Europe in scattered isolated populations that are of great conservation interest. Cleistogamy is common in the Stipa pennata group, the phylogeny of which is largely unresolved. Intraspecific patterns of genetic variation can be characterised by lack of gene flow due to selfing, but also by large-scale historical migrations and long-term isolation. We analysed both 5 species within the S. pennata group and 33 populations of Stipa pulcherrima sampled across a large part of its range. Using AFLP markers we assessed phylogenetic relationships of the S. pennata group and patterns of genetic variation within and among populations. The S. pennata group formed a consistent clade separated from S. capillata. Stipa pulcherrima was sister to S. eriocaulis, but the relationships among S. pennata s. str., S. borysthenica., and S. tirsa remained unresolved. Within-population genetic variation was extremely low in all species of the S. pennata group (H e = 0.0–0.013). In S. pulcherrima, genetic variation was consistently relatively high in the east (Romania, Russia) and declined toward western populations, with many populations at the western range edge lacking genetic variation entirely. Populations were strongly differentiated (F ST = 0.762), and this differentiation did not follow a classical pattern of isolation by distance. Bayesian cluster analysis revealed nine gene pools in S. pulcherrima, which were mostly geographically clustered. Overall the results suggest that S. pulcherrima and species of the S. pennata group are characterised by a cleistogamous breeding system leading to extremely low levels of genetic variation and high levels of population differentiation at both the population and species level. Postglacial colonisation, current population isolation, and population bottlenecks at the western range periphery have further reduced genetic variation and obviated gene exchange. Thus, genetic variation can only be preserved by the conservation of multiple populations.  相似文献   
89.
90.
Human mesenchymal stem cells (hMSCs) have great potential for clinical therapy and regenerative medicine. One major challenge concerning their application is the development of an efficient cryopreservation protocol since current methods result in a poor viability and high differentiation rates. A high survival rate of cryopreserved cells requires an optimal cooling rate and the presence of cryoprotective agents (CPA) in sufficient concentrations. The most widely used CPA, dimethylsulfoxide (Me2SO), is toxic at high concentrations at temperatures >4 °C and has harmful effects on the biological functionality of stem cell as well as on treated patients.Thus, this study investigates different combinations of non-cytotoxic biocompatible substances, such as ectoin and proline, as potential CPAs in a systematic parametric optimization study in comparison to Me2SO as control and a commercial freezing medium (Biofreeze®, Biochrom). Using a freezing medium containing a low proline (1%, w/v) and higher ectoin (10%, w/v) amount revealed promising results although the highest survival rate was achieved with the Biofreeze® medium. Cryomicroscopic experiments of hMSCs revealed nucleation temperatures ranging from −16 to −25 °C. The CPAs, beside Me2SO, did not affect the nucleation temperature. In most cases, cryomicroscopy revealed intracellular ice formation (IIF) during the cryopreservation cycle for all cryoprotocols. The occurence of IIF during thawing increased with the cooling rate. In case of hMSC there was no correlation between the rate of IIF and the post-thaw cell survival. After thawing adipogenic differentiation of the stem cells demonstrated cell functionality.  相似文献   
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