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881.
Hamed R. Goodarzi Ali Abbasi Mojtaba Saffari Mohammad B. Tabei Mohammad R. Noori Daloii 《Molecular biology reports》2010,37(6):2959-2965
Male Pattern Baldness (MPB) or androgenetic alopecia is a common form of hair loss with androgens and genetics having etiological
significance. Androgens are thought to pathophysiologically power on cascades of chronically dramatic alterations in genetically
susceptible scalp dermal papillas, specialized cells in hair follicles in which androgens react, and finally resulting in
a patterned alopecia. However, the exact mechanisms through which androgens, positive regulators of growth and anabolism in
most body sites, paradoxically exert their effects on balding hair follicles, are not yet known. The role of microRNAs, a
recently discovered class of non-coding RNAs, with a wide range of regulatory functions, has been documented in hair follicle
formation and their deregulation in cancer of prostate, a target organ of androgens has also been delineated. Yet, there is a lack of knowledge in agreement with microRNAs’ contribution in pathophysiology of MPB. To investigate the
role of microRNAs in pathogenesis of MPB, we selected seven microRNAs, predicted bioinformatically on a reverse engineering
basis, from previously published microarray gene expression data and analyzed their expression in balding relative to non-balding
dermal papillas. We found for the first time upregulation of four microRNAs (miR-221, miR-125b, miR-106b and miR-410) that
could participate in pathogenesis of MPB. Regarding microRNAs’ therapeutic potential and accessibility of hair follicles for
gene therapy, these microRNAs can be considered as good candidates for a new revolutionized generation of treatments. 相似文献
882.
Ranbir Chander Sobti Nega Berhane Salih Abedule Mehedi Rupinder Kler Seyed Ali Hosseini Vijish Kuttiat Ajay Wanchu 《Molecular biology reports》2010,37(1):317-324
Various efforts made to stop the deadly epidemic of HIV since its discovery in 1983 remain unsuccessful and this virus still
continues to claim the lives of millions of individuals every year. The viral effect in the cell is complicated and the overall
disease outcome is the result of interaction between a few viral proteins and complex host immune response. Because it has
been reported that XPG (Xeroderma pigementesum group G) gene does play a role in reducing UV induced apoptosis and participate in Nucleotide Excision
Repair (NER) process of DNA damage, it was hypothesized that polymorphism in this gene may have a role in HIV 1 disease progression
to AIDS. The aim of the present study, therefore, was to find out the association between XPG gene polymorphism and its effect on the rate of HIV 1 disease progression to AIDS. 300 HIV seropositive cases and an equal
number of age and sex matched controls were recruited for the study from north Indian population. The PCR-RFLP method was
utilized to genotype 600 study subject for the XPG Asp
1104
His gene polymorphism. There was significant difference in the frequency of the His/His variant genotype (OR 1.95, 95% CI = 1.93–3.63, P = 0.04) between cases and controls indicating a probable role of this gene in host viral interactions. 相似文献
883.
The pine processionary moth Thaumetopoea pityocampa (Den. & Schiff.) is one of the most harmful pests to pine species in Mediterranean countries including Turkey. Caterpillars of T. pityocampa are not only significantly harmful to forest trees but also responsible for various allergic reactions in humans and animals. In this study, in order to find a more effective and safe biological control agent against T. pityocampa, we investigated fungal pathogens of T. pityocampa in the Black Sea Region of Turkey and tested their pathogenicity on it. Five different fungi were isolated and identified based on their morphological and molecular characteristics including ITS and partial sequence of EF1-[alpha]. Based on these characteristics, four isolates were identified as Beauveria bassiana cf. Clade C (Rehner and Buckley in Mycologia 97:84–98, 2005) and one isolate was identified as Beauveria bassiana. Among these isolates, B. bassiana KTU-24, B. bassiana cf. Clade C KTU-66 and KTU-67 showed the highest virulence with 100% mortality within 10 days after application. B. bassiana isolate KTU-24 produced the highest mycosis value with %100. Consequently, B. bassiana KTU-24 seems to be good candidate for further investigation as a possible biological control agent against this pest. 相似文献
884.
Elif Şahin Horasan Gülden Ersöz Musa Göksu Feza Otag Ahmet Oner Kurt Sevim Karaçorlu Ali Kaya 《Mycopathologia》2010,170(4):263-268
Objectives
We aimed to asses possible clinically significant differences between C. parapsilosis and other candida species candidemia receiving care in the intensive care unit (ICU) setting.Methods
The study included 118 adult patients diagnosed as candidemia after admission to the ICU of a university hospital between January 2004 and December 2009. Data about demographic characteristics, underlying diseases, and risk factors for ICU-related candidemia were collected.Results
During the study period, 118 patients with candidemia were identified among 2,853 patients admitted into the ICU. Candidemia was seen in 41.4 cases per 1,000 ICU admissions. The overall incidence of candidemia in ICU patients during the study period was 2.09 per 1,000 hospital admissions. Of the isolates, 18.6% were C. albicans and 81.4% were C. non-albicans. The species most frequently isolated was C. parapsilosis (66.1%, 78/118). The distribution of other Candida spp. was as follows: 15 had C. tropicalis (12.7%) and 3 had C. glabrata (2.5%). By Statistical analysis, when patients with candidemia who had C. parapsilosis were compared with other Candida spp., the following factors were found to be significantly associated with C. parapsilosis fungemia; intravascular catheters (p = 0.008), malignity (p = 0.049) and age (p = 0.039). Relationship was found between C. tropicalis and hematologic malignancies (p = 0.001).Conclusions
When infections with a high mortality such as candidemia is suspected in critically ill patients, it is important to know local risk factors and epidemiological distributions of causative agents in selection of empirical and effective antifungal treatment. 相似文献885.
Yankovich TL Beresford NA Wood MD Aono T Andersson P Barnett CL Bennett P Brown JE Fesenko S Fesenko J Hosseini A Howard BJ Johansen MP Phaneuf MM Tagami K Takata H Twining JR Uchida S 《Radiation and environmental biophysics》2010,49(4):549-565
Environmental monitoring programs often measure contaminant concentrations in animal tissues consumed by humans (e.g., muscle). By comparison, demonstration of the protection of biota from the potential effects of radionuclides involves a comparison of whole-body doses to radiological dose benchmarks. Consequently, methods for deriving whole-body concentration ratios based on tissue-specific data are required to make best use of the available information. This paper provides a series of look-up tables with whole-body:tissue-specific concentration ratios for non-human biota. Focus was placed on relatively broad animal categories (including molluscs, crustaceans, freshwater fishes, marine fishes, amphibians, reptiles, birds and mammals) and commonly measured tissues (specifically, bone, muscle, liver and kidney). Depending upon organism, whole-body to tissue concentration ratios were derived for between 12 and 47 elements. The whole-body to tissue concentration ratios can be used to estimate whole-body concentrations from tissue-specific measurements. However, we recommend that any given whole-body to tissue concentration ratio should not be used if the value falls between 0.75 and 1.5. Instead, a value of one should be assumed. 相似文献
886.
Roghayeh Oskoueiyan Shahrokh Kazempour Osaloo Ali Asghar Maassoumi Taher Nejadsattari Valiollah Mozaffarian 《Biochemical Systematics and Ecology》2010
The phylogenetic status of the monotypic genus Vavilovia was studied using nrDNA ITS and cpDNA trnL-F and trnS-G regions. The results from the analysis of each dataset and the combined dataset, revealed that Vavilovia is closely related to Pisum, forming a group that is sister to Lathyrus. The molecular data and some morphological and biological characteristics strongly indicate that Vavilovia should be subsumed under Pisum, as Pisum formosum. 相似文献
887.
Sang Hyon Kim Mark Spensley Seung Kook Choi Cristiane P. G. Calixto Ali F. Pendle Olga Koroleva Peter J. Shaw John W. S. Brown 《Nucleic acids research》2010,38(9):3054-3067
Small nucleolar RNAs (snoRNAs) and small Cajal body-specific RNAs (scaRNAs) are non-coding RNAs whose main function in eukaryotes is to guide the modification of nucleotides in ribosomal and spliceosomal small nuclear RNAs, respectively. Full-length sequences of Arabidopsis snoRNAs and scaRNAs have been obtained from cDNA libraries of capped and uncapped small RNAs using RNA from isolated nucleoli from Arabidopsis cell cultures. We have identified 31 novel snoRNA genes (9 box C/D and 22 box H/ACA) and 15 new variants of previously described snoRNAs. Three related capped snoRNAs with a distinct gene organization and structure were identified as orthologues of animal U13snoRNAs. In addition, eight of the novel genes had no complementarity to rRNAs or snRNAs and are therefore putative orphan snoRNAs potentially reflecting wider functions for these RNAs. The nucleolar localization of a number of the snoRNAs and the localization to nuclear bodies of two putative scaRNAs was confirmed by in situ hybridization. The majority of the novel snoRNA genes were found in new gene clusters or as part of previously described clusters. These results expand the repertoire of Arabidopsis snoRNAs to 188 snoRNA genes with 294 gene variants. 相似文献
888.
Cahide Gokkusu Makbule Aydin Elif Ozkok Feti Tulubas Ali Elitok Burak Pamukcu Berrin Umman 《Cytokine》2010,49(1):58-63
Interleukin-15 (IL-15) is a potent proinflammatory cytokine that is now considered a key component of atherosclerosis. Proinflammatory gene polymorphisms lead to variations in the production and level of the proteins. In light of these findings, we hypothesized that variations in the gene coding for IL-15 influence the risk of coronary heart disease (CHD) by modulating the IL-15 levels. To test this hypothesis, we examined 5 single nucleotide polymorphisms (SNPs) in IL-15 gene and IL-15 levels in 102 patients with acute coronary syndrome (ACS), 102 patients with chronic ischemic stable CHD and 162 healthy control subjects. This study is the first report showing the influences of IL-15 gene variants and IL-15 levels on CHD. The five single nucleotide polymorphisms (SNPs) within the IL-15 gene, G367A, C267T, A14035T, C13687A, and A10504G were carried out by polymerase chain reaction/restriction fragment length polymorphism (PCR/RFLP). Serum IL-15 levels were significantly higher in both acute and chronic patients than in controls. Genetic variants of IL-15 gene and IL-15 levels were associated with CHD. In conclusion, our study supports the hypothesis that genetic variation in IL-15 gene and IL-15 levels influence the risk of CHD. Further studies are needed to confirm our hypothesis. 相似文献
889.
Mehran Talebinejad Adrian D.C. Chan Ali Miri 《Journal of electromyography and kinesiology》2010,20(6):1244-1248
In this paper, we present a new method for multi-scale analysis of electromyography signals based on an interesting fractal process known as multiplicative cascade multi-fractal. Using simulated needle electromyography signals, we show this method provides a means for discrimination of normal and neuropathic electromyography signals. We also present experimental results that show the new parameters, computed using multiplicative cascade multi-fractal modeling, are more robust than the conventional signal parameter, number of turns, in the presence of additive noise. Results of multiplicative cascade multi-fractal modeling are consistent with other multi-scale approaches; advantages and differences are high lighted. 相似文献
890.
Background: The seroprevalence rate of Helicobacter pylori in the Kingdom of Saudi Arabia (KSA) was reported to be in the range of 50–80% among mostly symptomatic patients in non‐community‐based studies. However, the seroprevalence of viral hepatitis A (HAV) underwent a marked decline in the last two decades from over 50% in 1989 to 25% in 1997 among Saudi children under the age of 12 years. The aim of this paper was to study seroprevalence rates of H. pylori and HAV among the adolescent population in three regions of KSA and to determine whether there was any correlation between them. Materials and methods: We randomly selected 1200 16–18‐year‐old students from three regions around KSA. Demographic data, including socioeconomic status (SES), were recorded, and each student was tested for the presence of H. pylori‐IgG antibodies and anti‐HAV‐IgG. Results: The results indicate a high H. pylori infection rate (47%) among this age group. Boys had a higher prevalence than girls (p = .03), and the Al‐Qaseem region had the highest prevalence (51%, p = .002). SES did not contribute to the high prevalence rates (p = .83). A cross‐tabulation of data showed that 88 (8%) of the teenagers were seropositive and that 512 (44%) were negative for both H. pylori and HAV antibodies (χ2 = 0.03, OR = 0.97, CI = 0.70–1.34). The agreement between H. pylori and HAV seropositivity was lower than would be predicted by chance (κ = ?0.03). The variables that were independently associated with seropositivity to H. pylori were being female (OR = 0.75, 95% CI = 0.60–0.95) and living in the Madinah region (OR = 0.72, 95% CI = 0.55–0.94). Conclusion: The prevalence of H. pylori in this group of adolescents was high. However, there was no correlation between H. pylori and HAV infection rates. Hence, factors contributing to the transmission source and route seem to be different. 相似文献