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741.
Genetic Background of Hirschsprung Disease: A Bridge Between Basic Science and Clinical Application 下载免费PDF全文
Afsane Bahrami Marjan Joodi Mehrdad Moetamani‐Ahmadi Mina Maftouh Seyed Mahdi Hassanian Gordon A. Ferns Amir Avan 《Journal of cellular biochemistry》2018,119(1):28-33
Hirschsprung's disease (HSCR) is a congenital disorder, defined by partial or complete loss of the neuronal ganglion cells in the intestinal tract, which is caused by the failure of neural crest cells to migrate completely during intestinal development during fetal life. HSCR has a multifactorial etiology, and genetic factors play a key role in its pathogenesis; these include mutations within several gene loci. These have been identified by screening candidate genes, or by conducting genome wide association (GWAS) studies. However, only a small portion of them have been proposed as major genetic risk factors for the HSCR. In this review, we focus on those genes that have been identified as either low penetrant or high penetrant variants that determine the risk of Hirschsprung's disease. J. Cell. Biochem. 119: 28–33, 2018. © 2017 Wiley Periodicals, Inc. 相似文献
742.
Rouya Ebrahimi Siamak Rahmanpour Youbert Ghoosta Mahdi Ghaffari 《Archives Of Phytopathology And Plant Protection》2013,46(16):2033-2042
Sclerotinia wilt of sunflower caused by Sclerotinia sclerotiorum (Lib.) De Bary is the major disease of sunflower (Helianthus annuus L.) in Iran. North-western areas of Iran demonstrate the most yield losses through the disease. Development of cultivars with adequate genetic resistance is necessary to avoid these losses. Evaluation of sunflower genotypes varies based on researchers and environmental conditions. Meanwhile, greenhouse tests of the sunflower genotypes are more reliable because of controlled conditions during the assessment activities. To study the reaction of the host plants under controlled conditions, three stem inoculation techniques, including mycelium plug (MP), oxalic acid solution (OAS) and wheat seeds infested (IWS) with Sclerotinia mycelium, were employed. Wounded and non-wounded treatments were used in the experiment to find their effect on the disease progress. Four genotypes, including Ghalami (local variety in market), Confeta, Alstar and Master, were inoculated in this study. The factor was the lesion length to evaluate the effectiveness of different inoculation procedures. The lesion length was measured after 3, 7, 10 and 14 days post inoculation. The analysis of variance demonstrated significant differences between IWS and two other methods (MP and OAS), where the IWS produced the longest lesion lengths. In contrast, the non-significant differences between MP and OAS methods might help researchers to employ the pathogenicity factor (oxalic acid) as an alternative inoculum for their studies. Master variety was the most tolerant genotype among the treatments and its viability was 100% even at 14?days after inoculation and incubation. Interestingly, there was no mortality in all cultivars before 7-day incubations, regardless of resistant or susceptible reactions. 相似文献
743.
Nega Berhane Rabinder Chandera Sobti Shiferaw Melesse Salih Abdul Mahdi Afework Kassu 《Molecular biology reports》2012,39(12):11125-11130
Prostate cancer (PCa) is the most common noncutaneous cancer among men, accounting for 10?% of male cancer-related deaths worldwide. The etiology of PCa is largely unknown, although multiple environmental and lifestyle factors such as ultraviolet irradiation, smoking, and diet might increase the risk of the disease. Risk of disease varies most prominently with age, ethnicity, family history, and diet. The multifunctional cytokine tumor necrosis factor alpha (TNF-α) has an important role in the pathogenesis of inflammatory, autoimmune and malignant diseases. In this case control study 150 Prostate cancer patients and 150 age matched benign prostate hyperplasia (BPH) and equal number of healthy control groups were involved. The aim of this study was to analyze the effect of TNF-α-308 (G/A) polymorphism on risk of prostate cancer on north Indian prostate cancer patients. The polymerase chain reaction (PCR) technique was utilized to genotype TNF-α-308 (G/A) polymorphism. The present study showed statistically significant increased risk of prostate cancer among individuals that carried the A allele of TNF-α-308 gene (OR?=?1.81, 95?% CI 1.00–3.481, p?=?0.03). 相似文献
744.
Mohammad Mahdi Najafpour 《Theorie in den Biowissenschaften》2012,131(4):265-272
In this paper, three different reactions of nanoparticles and proteins are explained. As a model system, the interactions of birnessite, which is a common manganese oxide in the environment, and bovine serum albumin, as a protein that has a strong affinity for a variety of inorganic molecules, are studied. The author proposes that the cofactor-formation in particular enzymes may be considered as a biomineralization in the presence of the protein. One of the numerous and very small nanoparticles produced in the presence of protein could be formed in an appropriate location in proteins and be used as a primitive inorganic core (cofactor) of enzyme. 相似文献
745.
Mohamad Reza Bayatiani Fatemeh Fallahi Akbar Aliasgharzadeh Mahdi Ghorbani Benyamin Khajetash Fatemeh Seif 《Reports of Practical Oncology and Radiotherapy》2021,26(1):50
BackgroundSymmetry and flatness are two quantities which should be evaluated in the commissioning and quality control of an electron beam in electron beam radiotherapy. The aim of this study is to compare symmetry and flatness obtained using three different dosimeters for various small and large fields in electron beam radiotherapy with linac.Materials and methodsBeam profile measurements were performed in a PTW water phantom for 10, 15 and 18 MeV electron beams of an Elekta Precise linac for small and large beams (1.5 × 1.5 cm2 to 20 × 20 cm2 field sizes). A Diode E detector and Semiflex-3D and Advanced Markus ionization chambers were used for dosimetry.ResultsBased on the obtained results, there are minor differences between the responses from different dosimeters (Diode E detector and Semiflex-3D and Advanced Markus ionization chambers) in measurement of symmetry and flatness for the electron beams. The symmetry and flatness values increase with increasing field size and electron beam energy for small and large field sizes, while the increases are minor in some cases.ConclusionsThe results indicate that the differences between the symmetry and flatness values obtained from the three dosimeter types are not practically important. 相似文献
746.
Temperature shock to early pupae causes wing color-pattern changes in butterflies. These plastic changes are ascribed to the hemolymph level of the cold-shock hormone (CSH) in pupae as well as to other mechanisms. Here, we characterized heat-shock-induced color-pattern changes using the blue pansy butterfly Junonia orithya (Lepidoptera: Nymphalidae). In response to the 38-42 °C heat-shock treatments, parafocal elements (PFEs) were thinned and dislocated away from eyespots; this was the reverse of the direction of the cold-shock-induced changes. Somewhat surprisingly, in response to the lethal 44 °C heat shock, PFEs were modified as in the case of a cold-shock. These modifications were not affected by the removal of the head-prothorax portion of pupae. While the hemolymph-mediated transfer of the possible PFE-modification property induced by the 42 °C treatment was unsuccessful in the parabiosis experiment, the transfer of the factor induced by the 44 °C treatment was successful. In contrast, reduction of the blue background area was obtained not only by the 42 and 44 °C treatments but also by the injection of thapsigargin, a plant-derived stress inducer, in males. The result of this treatment was similar to the natural color patterns of other closely related Junonia species. We also observed an increase in orange coloration by the 42 °C treatment in females, and this change was similar to ecdysteroid-induced modifications. Taken together, the heat-shock-induced PFE modifications in J. orithya can be explained by the levels of CSH, and other modifications are likely to be caused by general stress responses and ecdysteroid effects. We conclude that phenotypic plasticity of the wing color patterns to heat shock results from a combined effect of at least a few different mechanisms. These mechanisms might have been exploited in the color-pattern evolution of some Junonia species. 相似文献
747.
748.
Mahdi Zamani Flemming Pociot Peter Raeymaekers Jørn Nerup J.-J. Cassiman 《Human genetics》1996,98(4):491-496
Affected sib pair and linkage disequilibrium analysis, intrafamilial and case-control association studies were performed
on 81 Danish multiplex insulin-dependent diabetes mellitus (IDDM) families (382 individuals) and 82 healthy Danish controls.
The results confirm the linkage of D15S107 to IDDM in these Danish IDDM families (P = 0.010). When these data are combined with those of previous studies, an even stronger case for linkage can be made (P = 0.0005). Our analyses show that the D15S107*130 allele provides increased susceptibility (P = 0.02, relative risk = 3.55) and that the D15S107 locus contributes up to 16% of the familial clustering of IDDM. The analysis
of affected sib pairs suggests that HLA and D15S107 may possibly act independently of each other. Taken together with our
previous findings, our results suggest that three causes of susceptibilities can be discerned in the IDDM patient population:
(1) a major susceptibility caused by the HLA-DRB1 alleles; (2) a minor susceptibility caused by the joint action of HLA and
other non-HLA gene(s); and (3) a minor susceptibility caused by non-HLA gene(s).
Received: 18 March 1996 / Revised: 17 May 1996 相似文献
749.
Andrea J. Jani Jessie Bushell Cdric G. Arisdakessian Mahdi Belcaid Daniel M. Boiano Cathy Brown Roland A. Knapp 《The ISME journal》2021,15(6):1628
Infectious pathogens can disrupt the microbiome in addition to directly affecting the host. Impacts of disease may be dependent on the ability of the microbiome to recover from such disturbance, yet remarkably little is known about microbiome recovery after disease, particularly in nonhuman animals. We assessed the resilience of the amphibian skin microbial community after disturbance by the pathogen, Batrachochytrium dendrobatidis (Bd). Skin microbial communities of laboratory-reared mountain yellow-legged frogs were tracked through three experimental phases: prior to Bd infection, after Bd infection (disturbance), and after clearing Bd infection (recovery period). Bd infection disturbed microbiome composition and altered the relative abundances of several dominant bacterial taxa. After Bd infection, frogs were treated with an antifungal drug that cleared Bd infection, but this did not lead to recovery of microbiome composition (measured as Unifrac distance) or relative abundances of dominant bacterial groups. These results indicate that Bd infection can lead to an alternate stable state in the microbiome of sensitive amphibians, or that microbiome recovery is extremely slow—in either case resilience is low. Furthermore, antifungal treatment and clearance of Bd infection had the additional effect of reducing microbial community variability, which we hypothesize results from similarity across frogs in the taxa that colonize community vacancies resulting from the removal of Bd. Our results indicate that the skin microbiota of mountain yellow-legged frogs has low resilience following Bd-induced disturbance and is further altered by the process of clearing Bd infection, which may have implications for the conservation of this endangered amphibian.Subject terms: Microbial ecology, Community ecology 相似文献
750.
Maryam Salimi Abolfazl Shirazi Mohsen Norouzian Ameneh Jafari Haleh Edalatkhah Maryam Mehravar Mohammad Majidi Mohammad Mahdi Mehrazar 《Reports of Biochemistry & Molecular Biology》2020,9(3):357
Background:Currently, the efficient production of chimeric mice and their survival are still challenging. Recent researches have indicated that preimplantation embryo culture media and manipulation lead to abnormal methylation of histone in the H19/Igf2 promotor region and consequently alter their gene expression pattern. This investigation was designed to evaluate the relationship between the methylation state of histone H3 and H19/Igf2 expression in mice chimeric blastocysts.Methods:Mouse 129/Sv embryonic stem cells (mESCs) expressing the green fluorescent protein (mESCs-GFP) were injected into the perivitelline space of 2.5 days post-coitis (dpc) embryos (C57BL/6) using a micromanipulator. H3K4 and H3K9 methylation, and H19 and Igf2 expression was measured by immunocytochemistry and q-PCR, respectively, in blastocysts. Results:Histone H3 trimethylation in H3K4 and H3K9 in chimeric blastocysts was significantly less and greater, respectively (p< 0.05), than in controls. H19 expression was significantly less (p< 0.05), while Igf2 expression was less, but not significantly so, in chimeric than in control blastocysts.Conclusion:Our results showed, that the alteration ofH3K4me3 and H3K9me3 methylation, change H19/Igf2 expression in chimeric blastocysts.Key Words: Chimeric blastocysts, H19/Igf2, Histone 3 (H3) methylation 相似文献