Molekulare und genetische Medizin

Mutations in PRPF31 have been implicated in retinitis pigmentosa, a blinding disease caused by degeneration of rod photoreceptors. The disease mechanism in the majority of cases is haploinsufficiency. Crucially, attempts at generation of animal models of disease have proved unsuccessful, yielding animals with a visual phenotype that does not mirror human disease. This suggests that, in these animals, the transcriptional regulation of PRPF31 is different to humans and compared to other species. Study of the evolution of the PRPF31 core promoter has important implications for our understanding of human disease, as disease phenotype is modified by differentially expressed alleles in the population.

PRPF31 lies in a head-to-head arrangement with TFPT, a gene involved in cellular apoptosis. The two genes were shown to share common regulatory elements in the human genome. In this study, the core promoters of PRPF31 and TFPT were characterised by dual-luciferase reporter assay using genomic DNA from the green monkey, domestic dog and house mouse. It was found that the core promoters were conserved between human and monkey.

In dog, the TFPT core promoter was conserved, but different PRPF31 gene architecture meant the gene was controlled by a long-range promoter lying some 2000bp from the transcription start site.

There was very low level of conservation (<20%) of the PRPF31 5’ region between mouse and human. It was shown that mouse populations did not show variable Prpf31 expression levels, revealing a potential explanation for the lack of phenotype observed in the Prpf31 knock-out mouse model.

Bone homeostasis is maintained through a delicate balance between osteoblastic bone formation and osteoclastic bone resorption. Bone loss may be due to decreased osteoblastic bone formation and increased osteoclastic bone resorption. Osteoporosis is induced with its accompanying decrease in bone mass. Nutrition and functional food factors may play a role in the prevention of bone loss. This is worthy of notice in the treatment of osteoporsis. It has been shown that functional food factors including zinc, genistein and vitamin K2 (menaquinone-7) have potential osteogenic effects in vitro and in vivo. These factors have been shown to have stimulatory effects on osteoblastic bone formation and suppressive effects on osteoclastic bone resorption. Moreover, the osteogenic effects of genistein, menaquinone-7, and vitamin D3 have been found to be synergistically enhanced with combination of zinc, which plays an essential role in protein synthesis at translational process and gene expression related to zinc finger transcription factors. Intake with their combination has been shown to have potential effects in the treatment of bone loss in animal models of osteoporosis and human subjects. Supplemental intake with these compositions may have potential effects on osteoporosis treatment.

Pregnancy-induced hypertension (PIH) is one of a major cause of maternal mortality. Serum lipid profile plays pivotal role in the regulation of normal blood pressure during pregnancy. The aim of our study was to evaluate the alteration of serum lipid profile during normotensive and hypertensive pregnancy. This case-control study was conducted among the pregnant women visiting Jinnah Hospital Lahore, Pakistan from September, 2012 to March, 2013. Total 200 participants were evaluated out of which 50 were normotensive pregnant women (28 ± 8 years) taken as a normal control group and 150 were enrolled as hypertensive (30 ± 6 years) study group. Average blood pressure for normotensive pregnant women was 115/75 whereas, for hypertensive pregnant women it was 148.45/95.40. The levels of different serum lipids were measured using respective analytical kits. Hypertension was directly associated with increased levels of serum TGs (161.02 ± 3.58 vs. 105.31 ± 8.53), TC (188.90 ± 4.11 vs. 152.45 ± 1.99), LDL (136.50 ± 3.17 vs. 70.48 ± 2.14) and VLDL (117.06 ± 1.05 vs. 41.06 ± 1.70), and fall in HDL (49.41 ± 1.56 vs. 37.16 ± 1.64) as compared to that of normotensive pregnant women. The increased levels of TGs, TC, and LDL in hypertensive pregnant women were also correlated with significantly increased values of TC/HDL, TGs/HDL and LDL/HDL in hypertensive pregnant women. From the results of our study, it can be concluded that lipid profile plays their critical role in regulating blood pressure during pregnancy. Increased levels of TC, TGs, LDL and VLDL induced hypertension, whereas, HDL regulated the blood pressure to normal levels. This association may be significant in understanding the development of hypertension during pregnancy and may help in developing the strategies for prevention and treatment of PIH.

We investigated the occurence of genes associated with the production of carbapenem hydrolysing carbapenemases in Klebsiella pneumoniae isolates recovered from ICU patient. Antimicrobial susceptibility testing was performed and resistance genes were characterized by PCR amplification and sequencing. The Modified Hodge Test (MHT), MBL E-test, EDTA and aminophenylboronic acid (APBA) combined disk diffusion method, and a disk enzymatic assay were performed for the screening of carbapenemases. MICs of carbapenems were as follows (mg/L) ertapenem 8, meropenem 1, imipenem 0.25 and doripenem 0.5. The isolate demonstrated positive results in the ESBL, EDTA and APBA combined tests, and disk enzymatic assay. PCR and sequencing revealed the presence of bla_OXA-51and bla_CTX-M-15 beta-lactamase genes. Plasmids were not transferred to recipient E.coli by conjugation and transformation. In conclusion, we report on the first detection of the OXA-51 harboring K.pneumoniae isolate and co-produced a CTX-M-15 β-lactamase.

Background and objectives: Helicobacter pylori (H. Pylori) infection has serious consequences such as peptic ulcers and gastric cancer. Histologic identification of organisms remains the gold standard in the diagnosis of H. pylori. This meta-analysis reviewed the overall diagnostic accuracy of polymerase chain reaction (PCR) vs histology of H. pylori infection in the patients with otitis media with effusion (OME).

Methods: Medline, Scopus and ISI web of science were systematically searched. Articles meeting the selection criteria were retrieved for the data collection and analysis. Diagnostic odds ratio (DOR) and symmetric summary receiver operating characteristic (sROC) of OME -associated .H. pylori infection was estimated for each study. The PCR techniques were compared to the histological tests as the gold standard in .diagnosing H. pylori infection.

Results: We included eight relevant studies compromising 259 case of OME. The pooled sensitivity and specificity of PCR compared to the histological diagnosis of H. Pylori infection in patient with OME were 71% (95%CI: 61% - 80%, I2: 0.0%) and 81% (95%CI: 76% - 86%, I2: 59.9%), respectively. Pooled positive likelihood ratio (PLR) and negative likelihood ratio (NLR) for PCR were 3.61(95%CI: 2.34 – 5.59, I2: 44.5%) and 0.42 (95%CI: 0.31 – 0.57, I2: 0.1%), respectively. For DOR analysis, the pooled accuracy of PCR was 10.78 (95%CI: 5.95 – 19.53, I2: 0.0%) in diagnosing H. Pylori infection.

Conclusions: This review showed statistically significant differences in the diagnostic accuracy between the PCR and histological tests. This meta-analysis also suggests a higher sensitivity and specificity of PCR-based molecular diagnostic of H. Pylori infection in OME patients compared to the histological tests.

This study investigated the association of copy number variants (CNVs) in type 2 diabetes (T2D) and T2Dassociated end-stage renal disease (ESRD) in African Americans. Using the Affymetrix 6.0 array, >900,000 CNV probes spanning the genome were interrogated in 965 African Americans with T2D-ESRD and 1029 non-diabetic African American controls. Previously identified and novel CNVs were separately analyzed and were evaluated for insertion/deletion status and then used as predictors in a logistic regression model to test for association. One common CNV insertion on chromosome 1 was significantly associated with T2D-ESRD (p=6.17×10-5, OR=1.63) after multiple comparison correction. This CNV region encompasses the genes AMY2A and AMY2B, which encode amylase isoenzymes produced by the pancreas. Additional common and novel CNVs approaching significance with disease were also detected. These exploratory results require further replication but suggest the involvement of the AMY2A/AMY2B CNV in T2D and/or T2D-ESRD, and indicate that CNVs may contribute to susceptibility for these diseases.

A role for inflammation in the pathogenesis of Alzheimer's disease (AD) has been a matter of debate since the beginning of AD research in 1907. Over the past three decades immunohistochemical studies demonstrated that amyloid plaques are co-localized with activated microgliaas well as a broad spectrum of inflammation-related proteins (complement factors, acute-phase proteins, pro-inflammatory cytokines) spurring the hypothesis that amyloid plaques may benests of a non-immune mediated inflammatory reactions induced by fibrillar Aβ deposits. However, molecular studies also suggest that inflammation-related proteins are involved in Aβ generation and clearance, gliosis and increased phosphorylation of tau with accelerated tangle formation, i.e. several events considered key pathogenic steps in AD. In line with both notions, neuropathological studies show a close relation between fibrillar Aβ deposits, inflammation and neuroregeneration in relatively early stages preceding extensive tau-related neurofibrillary changes. Genetic studies address the issue of reverse causation and thus can help clarify the temporal relation between inflammatory changes and AD. In this review article we summarize the findings on inflammatory genes from the large scale genetic studies in AD and discuss directions for future research.

Cystic fibrosis (CF) is an autosomal recessive disease caused by more than 1,900 mutations in the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) gene. In CF, one intriguing aspect is that patients, with same CFTR mutation, can have high clinical variability. Thus, the CFTR genotype does not seem to be the only determining factor in the clinical severity modulation. Therefore, the modifier genes and the environment must be considered. The IFRD1 (Interferon-related developmental regulator 1) gene, acts on the immune system and in the recruitment of immune cells, and consequently could be a modulator. In our data we included 88 CF patients, diagnosed by CFTR mutation screening and positive sweat test. The 57460C>T polymorphism screening in the IFRD1 gene was made by polymerase chain reaction associated to enzymatic digestion. A genotypic comparison was performed with 23 CF clinical variables. The data was analyzed by the SPSS program considering α=0.05. The patients were analyzed considering the CFTR genotype characteristic by mutation class. In our data 64.77% of patients had mutations of classes I, II or III in the CFTR gene. The IFRD1 polymorphism frequency was 28 (12.99%), 35 (75.32%) and 25 (11.69%) to the CC, CT and TT genotypes, respectively. In our study, the 57460C>T polymorphism in the IFRD1 gene was not associated with the CF clinical variables. The analysis was performed with and without consideration of the CFTR genotype, and after correction for multiple testing (Bonferroni test), no positive association was observed in both cases. Taking into account our results, in the CF patients population analyzed, there were no associations of the 57460C>T polymorphism in the IFRD1 gene with the CF clinical variables.