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101.

Background

To investigate the association between polymorphism rs547984, located in close proximity to the Zona Pellucida Glycoprotein 4 (ZP4) gene on human chromosome 1q43 and primary open angle glaucoma (POAG).

Method

Polymorphism rs547984 was genotyped using Taq-Man® assay in 185 subjects comprising of 90 unrelated POAG cases and 95 controls of Saudi origin.

Results

Association analysis between cases and controls revealed no significant genotype distribution under additive (p = 0.356), dominant (p = 0.517) and recessive (p = 0.309) models. Besides, the allele frequency distribution was also found to be non-significant (p = 0.70). The minor “A” allele frequency was found to be 0.49 and 0.50 among POAG cases and controls, respectively. In addition, specific clinical indices used to assess severity of glaucoma such as intraocular pressure (IOP), cup/disc ratio and number of anti-glaucoma medication also did not show any significant genotype distribution in POAG cases.

Conclusion

Polymorphism rs547984 is neither associated with any clinical indices important for POAG such as IOP and cup/disc ratio nor is a risk factor for POAG in the Saudi cohort.
  相似文献   
102.
About 1.2 to 33% of high-altitude populations suffer from Monge’s disease or chronic mountain sickness (CMS). Number of factors such as age, sex, and population of origin (older, male, Andean) contribute to the percentage reported from a variety of samples. It is estimated that there are around 83 million people who live at altitudes > 2500 m worldwide and are at risk for CMS. In this review, we focus on a human “experiment in nature” in various high-altitude locations in the world—namely, Andean, Tibetan, and Ethiopian populations that have lived under chronic hypoxia conditions for thousands of years. We discuss the adaptive as well as mal-adaptive changes at the genomic and physiological levels. Although different genes seem to be involved in adaptation in the three populations, we can observe convergence at genetic and signaling, as well as physiological levels. What is important is that we and others have shown that lessons learned from the genes mined at high altitude can be helpful in better understanding and treating diseases that occur at sea level. We discuss two such examples: EDNRB and SENP1 and their role in cardiac tolerance and in the polycythemic response, respectively.  相似文献   
103.
104.

Objectives

This is a confirmatory study to evaluate the effect of photoinitiator type and concentration, matrix monomer chemical structure, and nanoparticle incorporation on the physical and mechanical properties of an experimental dentin bonding agent.

Materials and methods

Different concentrations of camphorquinone-amine (CQ-A) system, butanedione (BD), and phenylpropanedione (PPD), as photoinitiator, BTDMA, as a comonomer containing carboxylic acid groups, and silica nanoparticles as reinforcing inorganic filler were incorporated into a methacrylate base experimental dental adhesive. The effect of these ingredients, as independent variables, on the shrinkage kinetics, flexural strength and modulus, and microshear bond strength of the adhesives were then investigated. The results were analyzed using one-way ANOVA and Tukey’s post-hoc test at the significance level of 0.05.

Results

The results indicate that the efficiency of CQ-A initiator system is diminished in the presence of the acidic monomer BTDMA while the photopolymerization is efficiently progressed with BD as initiator. PPD shows the lowest efficiency in the photopolymerization of the adhesives. BTDMA as a monomer with the capability of interaction with tooth structure provides adhesive with improved microshear bond strength to dentin. Incorporation of silica nanoparticles at low concentrations enhances the flexural and microshear strength of the dentin bonding agent.

Significance

Understanding the structure–property relationship in dental adhesives may help the material selection in clinical dentistry. The study elucidates the relationship between monomer structure, initiator type, and nanofiller and physical and mechanical properties in dental adhesives.  相似文献   
105.
Voriconazole is commonly used for prophylaxis and treatment of invasive aspergillosis in lung transplant recipients. However, the use of voriconazole may at times be limited by the development of hepatotoxicity. Our goal is to determine predictors of voriconazole‐associated hepatotoxicity in lung transplant recipients. We conducted a single center retrospective cohort study of lung transplant recipients from 2006 to 2010 who received voriconazole therapy. We compared characteristics of patients who developed hepatotoxicity and those who did not. One hundred five lung transplant recipients received voriconazole. Hepatotoxicity occurred in 51% (54/105) of patients and lead to discontinuation in 34% (36/105). In univariate analysis, age less than 40 years, cystic fibrosis, use of azathioprine, history of liver disease and early initiation of voriconazole were associated with hepatotoxicity. In multivariable logistic regression analysis, perioperative initiation of voriconazole (within 30 days of transplantation) was independently associated with hepatotoxicity (OR 4.37, 95% CI: 1.53–12.43, p = 0.006). The five risk factors identified in the univariate analysis were used to build a K‐nearest neighbor algorithm predictive model for hepatotoxicity. This model predicted hepatotoxicity with an accuracy of 70%. Voriconazole therapy initiated within the first 30 days of transplantation is associated with a greater risk of developing hepatotoxicity.  相似文献   
106.
107.
In the month of Ramadan, patients with thyroid diseases, most of the time, do not need treatment adjustments and can fast safely without any health hazards. Patients with hypothyroidism taking thyroxine can take their tablets on an empty stomach at bedtime instead of half an hour before Sehr. Patients with hyperthyroidism, on methimazole/carbimazole can continue their dose in once or twice daily regimes, while those on propylthiouracil need to be switched. Hyperthyroid patients with severe symptoms should start treatment immediately and can avoid fast for few days after a consultation with their religious scholar.  相似文献   
108.
Please cite this paper as: Ziyaeyan et al. (2012) Pandemic 2009 influenza A H1N1 infection among 2009 Hajj Pilgrims from Southern Iran: a real‐time RT‐PCR‐based study. Influenza and Other Respiratory Viruses 6(601), e80–e84. Background Hajj is a mass gathering undertaken annually in Mecca, Saudi Arabia. The 2009 Hajj coincided with both the pandemic influenza A/H1N1 2009 (A(H1N1)pdm09) and seasonal types of influenza A viruses. The interaction between pandemic influenza and Hajj could cause both a high level of mortality among the pilgrims and the spread of infection in their respective countries upon their return home. Objective The present study attempted to determine the point prevalence of A(H1N1)pdm09 among returning Iranian pilgrims, most of whom had been vaccinated for seasonal influenza but not A(H1N1)pdm09. Methods Pharyngeal swabs were collected from 305 pilgrims arriving at the airport in Shiraz, Iran. RNA was extracted from the samples and A(H1N1)pdm09 and other seasonal influenza A viruses were detected using TaqMan real‐time PCR. For A(H1N1)pdm09‐positive samples, the sensitivity to oseltamivir was also evaluated. Results Subjects included 132 (43·3%) men and 173 (56·7%) women, ranging in age from 24 to 65 years. The A(H1N1)pdm09 virus was detected in five (1·6%) pilgrims and other influenza A viruses in eight (2·6%). All the A(H1N1)pdm09 were sensitive to oseltamivir. Conclusions Only five cases were found to be positive for A(H1N1)pdm09, and it seems unlikely that the arrival of infected pilgrims to their homelands would cause an outbreak of a new wave of infection there. Thus, the low morbidity and mortality rates among the pilgrims could be attributed to the characteristics of A(H1N1)pdm09, which causes morbidity and mortality in a way similar to the seasonal influenza infections, absence of high‐risk individuals among the Iranian pilgrims, and the instructions given to them about contact and hand hygiene, and respiratory etiquette.  相似文献   
109.

Purpose:

To compare the safety, efficacy, and dosing regimen of intravitreal ranibizumab as an adjunct to laser therapy for the treatment of macular edema secondary to branch retinal vein occlusion (BRVO).

Materials and Methods:

Thirty eyes of 30 patients of BRVO of at least 6 weeks duration were randomized into three groups: Group 1 received grid laser treatment alone, Group 2 received a single dose of intravitreal injection of ranibizumab (0.5 mg / 0.05 ml) followed by grid laser treatment on 7th day following injection, while Group 3 received three loading doses of intravitreal ranibizumab at monthly interval (i.e. 0, 1, & 2 months) + standard laser treatment 7 days after the 1st injection. Outcome measure noted at 6 months follow-up were the improvement in best-corrected visual acuity (BCVA) and central macular thickness (CMT).

Results:

At 6 months follow-up, there was an average gain of 12 letters (P=0.05), 17.5 letters (P=0.05) and 19 letters (P=0.05) in groups 1, 2, and 3, respectively, with the decrease in CMT being 208.7 μm (P=0.05), 312.9 μm (P= 0.05) and 326.8 μm (P=0.05), respectively, in these groups. Gain in BCVA of more than 3 lines was noted in 1/10 patients in Group 1(10%) as compared to 3/10 (30%) and 4/10 (40%) patients in groups 2 and 3, respectively.

Conclusion:

The gain in BCVA and reduction in CMT were better with combination therapy (single- and triple- dose regimen) compared to grid laser alone. Single dose of intravitreal ranibizumab with grid laser seems to be an effective therapy.  相似文献   
110.
In Bangladesh, clinical records of 323 patients with typhoid fever were reviewed to study the incidence, fatality, and optimal therapy of the complication of intestinal perforation. Fifteen patients (4.6%) developed intestinal perforation. Case-fatality rates were six of nine patients treated medically and one of four patients treated surgically for whom the postoperative courses were known. A literature review of 57,864 cases of typhoid fever in developing countries in the antibiotic era revealed that perforation developed in 2.5% of patients, a percentage that was similar to the incidence of 2.8% reported in the preantibiotic era. The median of case-fatality rates in these reports was 43% and the proportion of all reported typhoid deaths attributable to perforation was 25%. The case-fatality rates for patients with perforation were 70% for 410 patients managed medically and 26% for 1,835 patients managed surgically. Although some reports were biased toward placing patients at lower risk into surgical treatment, the large number of patients treated successfully by surgery suggests real improvement in surgical techniques in countries with endemic typhoid fever. These results indicate that intestinal perforation persists as a major cause of death in cases of typhoid fever in developing countries in the antibiotic era and that surgical treatment with use of antibiotic therapy is optimal for this complication.  相似文献   
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