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1.
Background: Aniridia is a rare developmental eye disorder characterized by complete or partial iris hypoplasia often accompanied with other ocular changes that affect the cornea, anterior chamber, lens, retina, and optic nerve. Most cases of aniridia are inherited with an autosomal dominant mode of inheritance caused by PAX6 mutations or deletions. To reveal the underlying genetic defect in a four-generation Iranian family with aniridia, we carried out a genetic screening of PAX6.

Methods: Complete ophthalmic examinations were performed for available affected family members. All PAX6 exons and their flanking regions were sequenced for affected individuals. Candidate variation was screened for segregation in the pedigree by Sanger sequencing. Bioinformatics prediction was done to evaluate the deleterious effects of the mutation on protein product. Real-time PCR was used to investigate the impact of the variant on PAX6 mRNA expression.

Results: All patients were diagnosed with isolated aniridia associated with variable phenotypic features including retinal detachment. A novel heterozygous deletion c.320_348delTGTCCGAGGGGGTCTGTACCAACGATAAC (p.Leu107HisfsX16) on PAX6 gene was detected. Decreased mRNA level of PAX6 in the affected individuals indicated that the mutation caused nonsense-mediated mRNA decay (NMD).

Conclusions: To the best of our knowledge, it is the first report on the genetics of aniridia in Iran. Segregation analysis, bioinformatics prediction and confirmation of NMD, all support the proposition that the novel observed PAX6 mutation is the cause of aniridia in the pedigree. Retinal detachment in some of the affected members, which is a rare reported phenotypic feature of aniridia patients, may be associated with this mutation.  相似文献   

2.
Vaccine-associated paralytic poliomyelitis (VAPP) is a rare complication of oral polio vaccine. We describe a fatal case of VAPP in an 8-month-old boy with Major Histocompatibility Class II deficiency. The isolated poliovirus was a Sabin type 2-type 1 recombinant that showed 1.4% VP1 divergence from Sabin type 2.  相似文献   
3.
Quality of Life Research - Examining the associations of a-posteriori-defined dietary patterns and health-related quality of life (HRQOL) among Iranian adolescents. This cross-sectional study was...  相似文献   
4.
Lasers in Medical Science - Diabetes mellitus is mostly interrelated to deficiency in wound healing. Low-level laser therapy has been shown to exert reliable effects on the acceleration of wound...  相似文献   
5.
The efficacy of spirulina platensis (S. platensis) as an add-on therapy to metformin and its effect on atherogenic keys in patients with uncontrolled Type 2 Diabetes Mellitus (T2DM) was evaluated. Sixty patients were randomly assigned to S. platensis (2 g/day) or placebo group for three months while continuing metformin as their usual treatment. The efficacy of S. platensis was determined using the pre- and post-intervention HbA1c levels (primary outcome) as well as tracking FBS and lipid profiles levels (TC, LDL-C, TG, and HDL-C) as secondary outcomes at the different treatment time points (0,30,60,90 days). During the three–month intervention period, supplementation with S. platensis resulted in a significant lowering of HbA1c (↓1.43, p < 0.001) and FBS (↓ 24.94 mg/dL, p < 001) levels. Mean TG in the intervention group was found to be significantly lower in the intervention group than in controls (p < 0.001). Total cholesterol (TC) and its fraction, LDL-C, exhibited a fall (↓41.36 mg/dL and ↓38.4 mg/dL, respectively; p < 0.001) coupled with a marginal increase in the level of HDL-C (↑3 mg/dL; p < 0.001). Add-on therapy with S. platensis was superior to metformin regarding long-term glucose regulation and controlling blood glucose levels of subjects with T2DM. Also, as a functional supplement, S. platensis has a beneficial effect on atherogenic keys (TG and HDL-C) with no adverse events.  相似文献   
6.
Retinoblastoma is an ocular tumor that occurs in young children, in either heritable or sporadic manner. The relative rarity of retinoblastoma, and the need for expensive equipment, anesthesia, and pediatric ophthalmologic expertise, are barriers for effective treatment in developing countries. Also, with an average age‐adjusted incidence of two to five cases per million children, patient number limits development of local expertise in countries with small populations. Lebanon is a small country with a population of approximately 4.5 million. In 2012, a comprehensive retinoblastoma program was formalized at the Children's Cancer Institute (CCI) at the American University of Beirut Medical Center, and resources were allocated for efficient interdisciplinary coordination to attract patients from neighboring countries such as Syria and Iraq, where such specialized therapy is also lacking. Through this program, care was coordinated across hospitals and borders such that patients would receive scheduled chemotherapy at their institution, and monthly retinal examinations and focal laser therapy at the CCI in Lebanon. Our results show the feasibility of successful collaboration across borders, with excellent patient and physician adherence to treatment plans. This was accompanied by an increase in patient referrals, which enables continued expertise development. However, the majority of patients presented with advanced intraocular disease, necessitating enucleation in 90% of eyes in unilateral cases, and more than 50% of eyes in bilateral cases. Future efforts need to focus on expanding the program that reaches to additional hospitals in both countries, and promoting early diagnosis, for further improvement of globe salvage rates.  相似文献   
7.
8.
We present a study on the synthesis, characterization and application of sodium carbonate tag silica-coated nano-Fe3O4 (Fe3O4@SiO2@(CH2)3OCO2Na) as a novel and efficient heterogeneous basic catalyst. The described catalyst was fully characterized via FT-IR, X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS), and field emission scanning electron microscopy (FE-SEM). The reported novel magnetic nanocatalyst presents an excellent activity and catalytic performance for the synthesis of a novel series of pyranocoumarins through the reaction of dialkyl acetylenedicarboxylates and 5,7-dihydroxy coumarin derivatives at 100 °C under solvent-free conditions.

We present a study on the synthesis, characterization and application of sodium carbonate tag silica-coated nano-Fe3O4 (Fe3O4@SiO2@(CH2)3OCO2Na) as a novel and efficient heterogeneous basic catalyst.  相似文献   
9.
10.
ABSTRACT

Alopecia areata (AA) is characterized by a genetically complex inheritance. HLA frequencies, as well as the single nucleotide polymorphism (SNP) in PTPN22, CTLA4, and IL2RA genes, have been described to be associated with AA susceptibility. So far, no independent replication of these studies has been reported, and no data exist on a possible association between AA disease and these SNPs or influence of HLA frequencies in Iranian population. A possible association between HLA-DRB1*11 alleles as well as a single variation in PTPN22, CTLA4, and IL2RA genes and patchy AA disease have been investigated in a cohort from Iran. Patient and control subjects were genotyped for PTPN22 (rs2476601), CTLA4 (rs3087243), and IL2RA (rs3118470) variations as well as HLA frequencies. Gene expression levels were analyzed by real-time RT-PCR. In contrast to PTPN22 and CTLA4 gene polymorphisms, a significant association was found between IL2RA SNP and susceptibility to AA in Iranian cohort. While gene expression levels of IL2RA and PTPN22 were higher in the patients than that of controls, CTLA4 expression levels found significantly lower in the patients. Despite a significant association between AA and HLA-DRB1*11 frequencies, the presence of DRB1*11 is not associated with PTPN22, CTLA4, or IL2RA gene SNPs. Although the minor allele in IL2RA SNP can be a significant determinant of AA disease development in Iranian population, reported an association between the PTPN22 and CTLA4 variations was not confirmed by our study. Furthermore, these genetic risk factors might act independently from HLA alleles.  相似文献   
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