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991.

Background

Ischemic stroke (IS) and coronary heart disease (CHD) are two vascular disorders that are a common cause of death worldwide. Several studies have assessed the association of the β-fibrinogen-455G/A (FGB-455G/A) polymorphism and risk of IS and CHD, but the results are still inconsistent. Our study aimed to investigate whether the FGB-455G/A polymorphism was associated with susceptibility to IS and CHD by using meta-analysis.

Methods

Relevant studies were identified from PubMed, Embase and four Chinese database up to July 2013.Data were analyzed and processed by Stata 11.2. A pooled OR with 95% CI was calculated to estimate the strength of the genetic association. Cumulative meta-analysis was performed to assess the tendency of pooled OR over time.

Results

45 studies based on a total of 7238 cases and 7395 controls were included in our meta-analysis. The results indicated that the FGB-455G/A polymorphism is associated with the risk of IS when compared with the dominant model (OR = 1.518, 95%CI = 1.279-1.802 for AA + GA vs. GG). In the subgroup analysis by ethnicity, significantly elevated risks were associated with the A allele in Asians (OR = 1.700, 95%CI = 1.417-2.040), but not in Caucasians (OR = 0.942, 95%CI = 0.813-1.091). Both the hypertension and non-hypertension subgroups reached significant results, but no significance was found when stratified according to sex or subtype of IS. Results indicate that the FGB-455G/A polymorphism is associated with CHD (OR = 1.802, 95%CI = 1.445-2.246).

Conclusion

Our meta-analysis suggests that the FGB-455G/A polymorphism contributes to susceptibility to IS and CHD.  相似文献   
992.
Tan AH  Low SY  Al Jajeh I 《Chest》2012,141(3):809-813
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The co-evolution of peptides and early cells some 3.7 billion years ago provided bioactive peptides with a long history for the proliferation and refinement of peptide hormones. Central to the adaptation and evolution of cell types in metazoans is the development of peptide signaling systems that regulate stress mechanisms. The corticotropin-releasing factor (CRF) family of peptides represents the canonical family of peptides that are pivotal to the regulation of stress in vertebrates. However, these peptides appear to have evolved at least 2 billion years after the formation of the first postulated bioactive peptides, suggesting that before this, other peptide systems played a role in stress and energy metabolism. The teneurin C-terminal associated peptides (TCAPs) are a recently discovered family of highly conserved peptides that are processed from the teneurin transmembrane proteins. This peptide/protein system is ubiquitous in multicellular organisms and evolved before the CRF family. TCAP-1 is a potent regulator of CRF-associated physiology and behavior and may play a significant role in the regulation of cell-to-cell communication and neuroplasticity in neurons.  相似文献   
997.
Context and Objective: Dyslipidemia in thyroid dysfunction has always been attributed to changes in thyroid hormone (TH) levels. We hypothesized that TSH plays an important role in lipid metabolism independent of TH. Design and Setting: We conducted a cross-sectional study to investigate the relationship between serum TSH levels and lipid profiles after controlling for free T(3), free T(4), total T(3), total T(4) and nonthyroid factors relevant to lipid metabolism in euthyroid Chinese subjects. Main Outcome Measures: General linear analysis was performed to determine whether the impact of TSH on serum lipid levels is independent of the TH levels. Moreover, path analysis, an evolutionary multivariable regression technique, was conducted to test whether there is a direct and/or indirect effect between serum TSH and total cholesterol (TC) levels. Additionally, the odds ratios (95% confidence interval) for hypercholesterolemia in relation to TSH categories were calculated. Results: A total of 3664 euthyroid subjects were finally analyzed. There was a significant linear trend toward higher log TC (P = 0.021) and log triglyceride (P = 0.001) levels with increasing serum TSH levels within the reference range, which remained significant after adjusting for factors such as TH levels, age, and smoking. Most importantly, the total effect of TSH on TC levels (total effect(TC, TSH) = 0.05253) includes a direct effect (direct effect(TC, TSH) = 0.05979) and an indirect effect via TH. Compared with subjects in the lower part of the reference range (TSH level, 0.27-0.61 mIU/liter), the adjusted odds ratio for hypercholesterolemia was 3.239 (95% confidence interval, 1.392-7.538; P = 0.007) for those in the upper category (TSH level, 4.61-5.5 mIU/liter). Conclusions: The variation in normal TSH levels is partially related to the lipid components and hypercholesterolemia in euthyroid subjects and includes both TH-dependent and TH-independent effects. Our study suggests the importance of controlling TSH in hypothyroid subjects.  相似文献   
998.
Testicular vasculitis (TV) may be part of systemic (testicular) vasculitis (STV) or may exist as single-organ/isolated (testicular) vasculitis (ITV). In the current study we sought to identify clinical and histologic features that distinguish STV from ITV. The distinction was deemed important because it is already well established that in other forms of single organ vasculitis, surgical therapy alone may be curative. We identified patients with biopsy-proven TV from pathology databases from our institution and from an English-language PubMed search. Patients were included if data were available to determine TV extent confidently. Data recorded included clinical, laboratory, and histologic features; treatment; and clinical follow-up. The study included 72 patients with TV (mean age, 42 yr; range, 4-78 yr) (7 from our institution). About 74% of patients presented with painful testicular swelling/mass, 10% with a painless testicular swelling/mass, and 4% with epididymal swelling/mass. Eleven percent had no testicular complaints and vasculitis was discovered at autopsy or in other surgical interventions. Vasculitis involved the testicle in 80.3% of cases, the epididymis in 44.6%, and the spermatic cord in 30.6%. Thirty-seven (51%) patients had ITV and 35 (49%) had STV. No differences between ITV and STV patients were found in regards to age, presenting testicular features, duration of testicular symptoms, and time of follow-up. Compared to ITV patients, STV patients presented more often with constitutional/musculoskeletal symptoms (74.3% vs. 8.3%, respectively; p = 0.0001), elevated erythrocyte sedimentation rate (94.7% vs. 16%; p = 0.0001), and anemia (50% vs. 0%; p = 0.0001). Neoplasm was more frequently suspected in ITV than in STV (74.2% vs. 31.6%; p = 0.001), but only occurred in 2 ITV patients. Long-term glucocorticoid therapy was given only to STV patients, and 59.1% of them also received cytotoxic agents. ITV was diagnosed more often by orchiectomy (81.1% vs. 42.9%; p = 0.001) and less frequently by testicular biopsy (2.7% vs. 28.6%; p = 0.003) than STV. Nongranulomatous inflammation affecting medium-sized vessels occurred in most patients with both ITV and STV. Among STV, polyarteritis nodosa was the most frequently diagnosed (63%), followed by Wegener granulomatosis (17%).In summary, TV occurs as ITV in men usually presenting with a testicular mass in the absence of systemic symptoms and normal laboratory results. In most ITV patients, a testicular neoplasm is initially suspected, and TV is an unexpected finding. After surgical removal, ITV does not require systemic therapy. Polyarteritis nodosa is the systemic vasculitis most frequently associated with testicular involvement.  相似文献   
999.
In most sexually reproducing animals, replication and maintenance of telomeres occurs in the germ line and during early development in embryogenesis through the use of telomerase. Somatic cells generally do not maintain telomere sequences, and these cells become senescent in adults as telomeres shorten to a critical length. Some animals reproduce clonally and must therefore require adult somatic mechanisms for maintaining their chromosome ends. Here we study the telomere biology of planarian flatworms with apparently limitless regenerative capacity fueled by a population of highly proliferative adult stem cells. We show that somatic telomere maintenance is different in asexual and sexual animals. Asexual animals maintain telomere length somatically during reproduction by fission or when regeneration is induced by amputation, whereas sexual animals only achieve telomere elongation through sexual reproduction. We demonstrate that this difference is reflected in the expression and alternate splicing of the protein subunit of the telomerase enzyme. Asexual adult planarian stem cells appear to maintain telomere length over evolutionary timescales without passage through a germ-line stage. The adaptations we observe demonstrate indefinite somatic telomerase activity in proliferating stem cells during regeneration or reproduction by fission, and establish planarians as a pertinent model for studying telomere structure, function, and maintenance.  相似文献   
1000.
Tan DT  Dart JK  Holland EJ  Kinoshita S 《Lancet》2012,379(9827):1749-1761
Corneal transplantation or keratoplasty has developed rapidly in the past 10 years. Penetrating keratoplasty, a procedure consisting of full-thickness replacement of the cornea, has been the dominant procedure for more than half a century, and successfully caters to most causes of corneal blindness. The adoption by specialist surgeons of newer forms of lamellar transplantation surgery, which selectively replace only diseased layers of the cornea, has been a fundamental change in recent years. Deep anterior lamellar keratoplasty is replacing penetrating keratoplasty for disorders affecting the corneal stromal layers, while eliminating the risk of endothelial rejection. Endothelial keratoplasty, which selectively replaces the corneal endothelium in patients with endothelial disease, has resulted in more rapid and predictable visual outcomes. Other emerging therapies are ocular surface reconstruction and artificial cornea (keratoprosthesis) surgery, which have become more widely available because of rapid advances in these techniques. Collectively, these advances have resulted in improved outcomes, and have expanded the number of cases of corneal blindness, which can now be treated successfully. Femtosecond-laser-assisted surgery, bioengineered corneas, and medical treatment for endothelial disease are also likely to play a part in the future.  相似文献   
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