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101.

Background

Few studies have systematically addressed the role of epidural analgesia and caesarean delivery in predicting the post-partum disease activity in women with Multiple Sclerosis (MS).The objective of this study was to assess the impact of epidural analgesia (EA) and caesarean delivery (CD) on the risk of post-partum relapses and disability in women with MS.

Methods

In the context of an Italian prospective study on the safety of immunomodulators in pregnancy, we included pregnancies occurred between 2002 and 2008 in women with MS regularly followed-up in 21 Italian MS centers. Data were gathered through a standardized, semi-structured interview, dealing with pregnancy outcomes, breastfeeding, type of delivery (vaginal or caesarean) and EA. The risk of post-partum relapses and disability progression (1 point on the Expanded Disability Status Sclae, EDSS, point, confirmed after six months) was assessed through a logistic multivariate regression analysis.

Results

We collected data on 423 pregnancies in 415 women. Among these, 349 pregnancies resulted in full term deliveries, with a post-partum follow-up of at least one year (mean follow-up period 5.5±3.1 years). One hundred and fifty-five patients (44.4%) underwent CD and 65 (18.5%) EA. In the multivariate analysis neither CD, nor EA were associated with a higher risk of post-partum relapses. Post-partum relapses were related to a higher EDSS score at conception (OR=1.42; 95% CI 1.11-1.82; p=0.005), a higher number of relapses in the year before pregnancy (OR=1.62; 95% CI 1.15-2.29; p=0.006) and during pregnancy (OR=3.07; 95% CI 1.40-6.72; p=0.005). Likewise, CD and EA were not associated with disability progression on the EDSS after delivery. The only significant predictor of disability progression was the occurrence of relapses in the year after delivery (disability progression in the year after delivery: OR= 4.00; 95% CI 2.0-8.2; p<0.001; disability progression over the whole follow-up period: OR= 2.0; 95% CI 1.2-3.3; p=0.005).

Conclusions

Our findings, show no correlation between EA, CD and postpartum relapses and disability. Therefore these procedures can safely be applied in MS patients. On the other hand, post-partum relapses are significantly associated with increased disability, which calls for the need of preventive therapies after delivery.
  相似文献   
102.
Animals possess conserved mechanisms to detect pathogens and to improve survival in their presence by altering their own behavior and physiology. Here, we utilize Caenorhabditis elegans as a model host to ask whether bacterial volatiles constitute microbe‐associated molecular patterns. Using gas chromatography–mass spectrometry, we identify six prominent volatiles released by the bacterium Pseudomonas aeruginosa. We show that a specific volatile, 1‐undecene, activates nematode odor sensory neurons inducing both flight and fight responses in worms. Using behavioral assays, we show that worms are repelled by 1‐undecene and that this aversion response is driven by the detection of this volatile through AWB odor sensory neurons. Furthermore, we find that 1‐undecene odor can induce immune effectors specific to P. aeruginosa via AWB neurons and that brief pre‐exposure of worms to the odor enhances their survival upon subsequent bacterial infection. These results show that 1‐undecene derived from P. aeruginosa serves as a pathogen‐associated molecular pattern for the induction of protective responses in C. elegans.  相似文献   
103.
Disproportionately large feeding structures have been used to infer food limitation in some marine invertebrate larvae, but few studies have investigated whether other factors alter larval morphology in similar ways. In this study, larvae of Crepidula fornicata were reared either at five different food concentrations of Isochrysis galbana (clone T-ISO) at a single temperature (22 degrees C) (Experiments I and II); or on three different phytoplankton species (Isochrysis galbana, Dunaliella tertiolecta, and Pavlova lutheri) at both high and low concentrations at a single temperature (22 degrees C) (Experiment III); or at high and low concentrations of Isochrysis galbana at four different temperatures between 16 and 25 degrees C (Experiment IV). Shell lengths and velar lobe dimensions were determined for individual larvae at intervals to monitor relative rates of velar and shell growth. In addition (Experiment V), fast growing and slow growing larvae in Experiment I were examined separately to determine whether velar lobes developed at similar rates (relative to shell growth) for fast and slow growing larvae within individual cultures. In general, velar lobes grew significantly larger, relative to shell length, when larvae were reared at low food concentrations (P<0.0001); for larvae of similar shell length, the velar lobes of those fed 1x10(4) cells ml(-1) were on average 17.7% larger than those of larvae fed 18x10(4) cells ml(-1) of T-ISO. In contrast, larvae fed different phytoplankton species at equivalently high food concentrations did not differ in relative velum size (P=0.2666), even though shell growth rates differed significantly for larvae raised on the different diets, indicating substantial variation in food quality. We also found that relative rates of velum and shell growth differed among fast and slow growing individuals within treatments. Temperature had no significant effect on relative rates of velar and shell growth within the 16-25 degrees C range tested (P=0.121), but may have altered the relationship between food concentration and relative velar growth. These results indicate that dramatically reduced food concentration induces disproportionate growth in the velar lobes of C. fornicata, but that interpretation of data from field-collected individuals of this species will be made difficult by the potentially confounding effects of temperature, food quality, and differences in individual growth potential. Assessments of food limitation using morphological measurements for field-collected larvae will need to be supplemented with other indicators before convincing conclusions about the extent of food limitation in C. fornicata can be drawn.  相似文献   
104.
Genetic divergence and gene flow among closely related populations are difficult to measure because mutation rates of most nuclear loci are so low that new mutations have not had sufficient time to appear and become fixed. Microsatellite loci are repeat arrays of simple sequences that have high mutation rates and are abundant in the eukaryotic genome. Large population samples can be screened for variation by using the polymerase chain reaction and polyacrylamide gel electrophoresis to separate alleles. We analyzed 10 microsatellite loci to quantify genetic differentiation and hybridization in three species of North American wolflike canids. We expected to find a pattern of genetic differentiation by distance to exist among wolflike canid populations, because of the finite dispersal distances of individuals. Moreover, we predicted that, because wolflike canids are highly mobile, hybrid zones may be more extensive and show substantial changes in allele frequency, relative to nonhybridizing populations. We demonstrate that wolves and coyotes do not show a pattern of genetic differentiation by distance. Genetic subdivision in coyotes, as measured by theta and Gst, is not significantly different from zero, reflecting persistent gene flow among newly established populations. However, gray wolves show significant subdivision that may be either due to drift in past Ice Age refugia populations or a result of other causes. Finally, in areas where gray wolves and coyotes hybridize, allele frequencies of gray wolves are affected, but those of coyotes are not. Past hybridization between the two species in the south-central United States may account for the origin of the red wolf.   相似文献   
105.

Background  

The 3-D structure of none of the eukaryotic sialyltransferases (SiaTs) has been determined so far. Sequence alignment algorithms such as BLAST and PSI-BLAST could not detect a homolog of these enzymes from the protein databank. SiaTs, thus, belong to the hard/medium target category in the CASP experiments. The objective of the current work is to model the 3-D structures of human SiaTs which transfer the sialic acid in α2,3-linkage viz., ST3Gal I, II, III, IV, V, and VI, using fold-recognition and comparative modeling methods. The pair-wise sequence similarity among these six enzymes ranges from 41 to 63%.  相似文献   
106.
Gastric epithelial cells are important components of mucosal protection and targets of nonsteroidal anti-inflammatory drugs (NSAIDs)-induced injury. Diclofenac (DFN) is one of the most widely used NSAIDs; however, even its short-term use can induce gastric erosions and ulcers. Nerve growth factor (NGF) has been reported to act not only on neuronal cells but also on endothelial cells; however, its action on gastric epithelial cells is unknown. This study was aimed to determine, whether NGF can protect gastric epithelial cells against DFN-induced injury, and to determine the underlying molecular mechanisms with a focus on mitochondria, survivin, and insulin-like growth factor 1 (IGF-1). Cultured normal rat gastric mucosal epithelial cells 1 (RGM1) were treated with phosphate-buffered saline (PBS; control), NGF (100 ng/mL) and/or DFN (0.25-1.00 mM) for 4 hours. We examined: (1) cell injury by confocal microscopy; (2) cell death/survival using Calcein AM live cell tracking dye; (3) mitochondrial structure and membrane potential function using MitoTracker in live cells; and (4) expression of NGF, its receptor - tropomyosin receptor kinase A (TrkA), survivin and IGF-1 by immunostaining. DFN treatment of RGM1 cells for 4 hours caused extensive cell injury, mitochondrial disintegration, reduced cell viability (from 94 ± 3% in controls to 14 ± 4% in 0.5 mM DFN-treated cells; P < 0.001), and expression of survivin and IGF-1. NGF treatment significantly increased survivin and IGF-1 expression by 41% and 75%, respectively versus PBS controls. Pretreatment with NGF before DFN treatment reduced mitochondrial damage and cell death by 73% and 82%, respectively versus treatment with DFN alone (all P < 0.001). This study also showed the presence of high-affinity TrkA receptors in the plasma membrane and mitochondria of RGM1 cells indicating novel actions of NGF.  相似文献   
107.
Molecular dynamics calculations were carried out on models of two synthetic leucine-serine ion channels: a tetrameric bundle with sequence (LSLLLSL)(3)NH(2) and a hexameric bundle with sequence (LSSLLSL)(3)NH(2). Each protein bundle is inserted in a palmitoyloleoylphosphatidylcholine bilayer membrane and solvated by simple point charge water molecules inside the pore and at both mouths. Both systems appear to be stable in the absence of an electric field during the 4 ns of molecular dynamics simulation. The water motion in the narrow pore of the four-helix bundle is highly restricted and may provide suitable conditions for proton transfer via a water wire mechanism. In the wider hexameric pore, the water diffuses much more slowly than in bulk but is still mobile. This, along with the dimensions of the pore, supports the observation that this peptide is selective for monovalent cations. Reasonable agreement of predicted conductances with experimentally determined values lends support to the validity of the simulations.  相似文献   
108.
Fluorosis is a metabolic disease that is endemic in nearly 25 countries with India being one of the most affected. It primarily affects the bone and the teeth. Moringa oleifera (MO) leaves are known to reduce the effect of fluorosis on various tissues. Therefore, it is of interest to document the effect of Moringa oleifera leaves on the hematological profile of fluorosis affected rats. Twenty four Sprague Dawley rats were housed two per cage in a room with 12 hours light and 12 hours dark cycle. The rats were allowed to adjust to the laboratory environment for about one to two weeks before the beginning of the study. This study reveals that MO leaves is effective in reducing the plasma fluoride content. It also helps in improving the Hb % and RBC count in fluorosis affected rats. Data shows that Moringa olifera leaves powder is effective in reducing the plasma fluoride content. It also helps in improving the Hemoglobin percentage & Red Blood Cell count in fluorosis affected rats.  相似文献   
109.
We evaluated the activity of methanolic extracts of Melaleuca cajuputi flowers against the filarial worm Brugia pahangi and its bacterial endosymbiont Wolbachia. Anti-Wolbachia activity was measured in worms and in Aedes albopictus Aa23 cells by PCR, electron microscopy, and other biological assays. In particular, microfilarial release, worm motility, and viability were determined. M. cajuputi flower extracts were found to significantly reduce Wolbachia endosymbionts in Aa23 cells, Wolbachia surface protein, and microfilarial release, as well as the viability and motility of adult worms. Anti-Wolbachia activity was further confirmed by observation of degraded and phagocytized Wolbachia in worms treated with the flower extracts. The data provided in vitro and in vivo evidence that M. cajuputi flower extracts inhibit Wolbachia, an activity that may be exploited as an alternative strategy to treat human lymphatic filariasis.  相似文献   
110.
Lake Ichkeul in northern Tunisia is a Ramsar site, a MAB Biosphere Reserve and a UNESCO World Heritage Site. The system is one of the most important coastal wetlands in North Africa, especially as an over-wintering area for migratory birds, particularly Palaearctic waterfowl. The present study was aimed at diagnosing the status of fish species in Lake Ichkeul and documenting their annual and seasonal occurrence within the system. Fish samples were collected monthly at 22 sites from March 2011 to April 2012 using a variety of gears, including a dragnet, gillnet, trammelnet, frynet and beach-seine. Temperature and salinity measurements were taken at each site, while fishes were obtained from only 11 sites, representing mainly lacustrine stations. A total of 18 fish species belonging to 14 genera and 12 families were identified, with Mugilidae dominating with four species, followed by Syngnathidae with three species. This study represents a relative recovery in terms of fish species richness, since only 13 species were recorded here between 2003 and 2007. However, the numbers of fish caught, especially of the commercial taxa, seem to have declined in recent years, and the number of species currently present is much lower than that of several decades ago. Increasing human pressures, particularly reductions in catchment freshwater inputs, a breakdown in ecosystem connectivity, pollution and over-fishing appear to be the principal causes for the decline in fish abundance and diversity.  相似文献   
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