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141.
Rheumatoid arthritis (RA) is a chronic autoimmune disorder associated with altered expression of pro-inflammatory cytokines. We aim to elucidate the association between the −308G/A polymorphism of the TNF-α gene and 196M/R polymorphism in TNFRII gene and susceptibility and severity of RA. One hundred and seventy-two RA patients and one hundred and sixty controls were enrolled in the study. Polymorphisms (SNPs) at position −308 of TNF and −196 of TNFRII genes were determined using restriction fragment length polymorphism–polymerase chain reaction (PCR–RFLP). TNF AA genotype was more prevalent among the patients. GG genotype was significantly more likely to have erosive arthropathy. TNFRII RR genotype was more prevalent among the patients. Our findings suggest that the 308AA genotype of TNF-α and TNFRII 196M/R polymorphism are associated with RA susceptibility. While only the 308GG genotype of TNF-α is associated with RA severity.  相似文献   
142.
Gharib AF  Karam RA  Pasha HF  Radwan MI  Elsawy WH 《Gene》2011,489(2):98-102
Hereditary hemochromatosis and alpha-1antitrypsin deficiency are genetic diseases characterized by endoplasmic reticulum (ER) stress with subsequent development of liver disease. Our aim was to estimate the frequency of hemochromatosis gene (HFE) mutant alleles (C282Y and H63D) and alpha-1 antitrypsin S/Z variants among Egyptian HCV cirrhotic patients and in hepatocellular carcinoma patients and to evaluate their effects on disease progression. HFE and alpha-1 antitrypsin polymorphisms were characterized in 200 Egyptian patients with HCV infection (100 patients complicated with cirrhosis, 100 patients with HCC) and 100 healthy subjects who had no history of any malignancy. The frequencies of HD genotype of H63D mutation were significantly increased in HCC patients compared to control group and to cirrhosis group. Also, the frequencies of DD genotype were significantly increased In HCC group compared to control group and to cirrhosis group. Our results suggested that Carriers of the D allele of H63D mutation were significantly more likely to develop HCC.  相似文献   
143.
An optimally functional brain requires both excitatory and inhibitory inputs that are regulated and balanced. A perturbation in the excitatory/inhibitory balance—as is the case in some neurological disorders/diseases (e.g. traumatic brain injury Alzheimer’s disease, stroke, epilepsy and substance abuse) and disorders of development (e.g. schizophrenia, Rhett syndrome and autism spectrum disorder)—leads to dysfunctional signaling, which can result in impaired cognitive and motor function, if not frank neuronal injury. At the cellular level, transmission of glutamate and GABA, the principle excitatory and inhibitory neurotransmitters in the central nervous system control excitatory/inhibitory balance. Herein, we review the synthesis, release, and signaling of GABA and glutamate followed by a focused discussion on the importance of their transport systems to the maintenance of excitatory/inhibitory balance.  相似文献   
144.

Background

Several rehabilitation programmes aim at reducing the impact of fatigue in MS patients. Acute and chronic fatigue should require different management.

Objectives

To assess the effects of individually tailored, multidisciplinary outpatient rehabilitation (MDR) on chronic fatigue.

Methods

Forty-eight ambulatory MS patients with chronic fatigue were randomized to MDR or to MS–nurse consultation. Fatigue was assessed by the Checklist Individual Strength (CIS-20R). Secondary outcomes included the Modified Fatigue Impact Scale, Fatigue Severity Scale, Functional Independence Measure, Disability and Impact Profile (DIP), Multiple Sclerosis Impact Scale and the Impact on Participation and Autonomy (IPA).

Results

The primary outcome measure CIS-20R overall score showed no significant differences between groups at 12 weeks (P = 0.39) and 24 weeks follow-up (P = 0.14), nor for subscales (t = 12 and t = 24, 0.19≤P≤0.88). No significant within-group effects were found for both groups with respect to the primary (0.57≤p≤0.97) and secondary (0.11≤p≤0.92) outcome measures from baseline to 12 or 24 weeks.

Conclusion

Multidisciplinary rehabilitation was not more effective in terms of reducing self-reported fatigue in MS patients compared to MS-nurse consultation. Our results suggest that chronic fatigue in patients with MS may be highly invariant over time, irrespective of interventions.

Trial Registration

controlled-trials.com ISRCTN05017507  相似文献   
145.
146.
147.

Background

Although quiescence (reversible cell cycle arrest) is a key part in the life history and fate of many mammalian cell types, the mechanisms of gene regulation in quiescent cells are poorly understood. We sought to clarify the role of microRNAs as regulators of the cellular functions of quiescent human fibroblasts.

Results

Using microarrays, we discovered that the expression of the majority of profiled microRNAs differed between proliferating and quiescent fibroblasts. Fibroblasts induced into quiescence by contact inhibition or serum starvation had similar microRNA profiles, indicating common changes induced by distinct quiescence signals. By analyzing the gene expression patterns of microRNA target genes with quiescence, we discovered a strong regulatory function for miR-29, which is downregulated with quiescence. Using microarrays and immunoblotting, we confirmed that miR-29 targets genes encoding collagen and other extracellular matrix proteins and that those target genes are induced in quiescence. In addition, overexpression of miR-29 resulted in more rapid cell cycle re-entry from quiescence. We also found that let-7 and miR-125 were upregulated in quiescent cells. Overexpression of either one alone resulted in slower cell cycle re-entry from quiescence, while the combination of both together slowed cell cycle re-entry even further.

Conclusions

microRNAs regulate key aspects of fibroblast quiescence including the proliferative state of the cells as well as their gene expression profiles, in particular, the induction of extracellular matrix proteins in quiescent fibroblasts.  相似文献   
148.
149.

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   
150.
Two semi-arid tropical grasslands, one of an alfisol and the other on vertisol were sampled for earthworm populations during July 1985 to July 1987. The soil of the alfisol grassland was slightly acidic while that of the vertisol was slightly alkaline. The alfisol grassland has a lower range of soil moisture, soil temperature, electrical conductivity, organic carbon, available nitrogen and potassium, and a higher range of phosphorus compared to the vertisol. The alfisol grassland was inhabited byOctochaetona phillotti (Michaelsen) with rare occurrence ofBarogaster annandalei (Stephenson) whereas the vertisol grassland was inhabited only byB. annandalei. The total population ofO. phillotti ranged between 16 and 96/m2 while its juvenile population ranged between 3.2 and 25.6/m2, pre-adult population between 5.3 and 53.6/m2 and adult population between 0 and 28.8/m2. The total population ofB. annandalei ranged between 3.2 and 58.3/m2 and its juvenile population between 0 and 26.6/m2, pre-adult population 0 and 10.6/m2 and adult population between 0 and 22.4/m2. The earthworms migrated to deeper layers during winter and summer,O. phillotti reaching a maximum depth of 40 cm andB. annandalei reaching a depth of 45 cm, and seen in quiescent stage. Their seasonal population structure was significantly influenced by the seasonal patterns in rainfall, soil temperature, pH, electrical conductivity and phosphorus. These variables along with organic carbon, available nitrogen and potassium together accounted for 32–63% and 79–91% respectively, of the variation in seasonal population fluctuation of differentO. phillotti andB. annandalei age groups. The physical factors of the soil were collectively more effective in causing the seasonal variation in their population size than the chemical factors.Visiting scientist (under the Rockefeller Foundation Environmental Research Fellowship in International Agriculture) in Resource Management Programme of ICRISAT, Andhra Pradesh, India  相似文献   
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