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61.
Ender Karaca Elif Karakoc-Aydiner Omer Faruk Bayrak Sevgi Keles Serhat Sevli Isil B. Barlan Adnan Yuksel Talal A. Chatila Mustafa Ozen 《Gene》2013
Protein tyrosine kinases (PTKs) play an important role in T cell development and activation. In vitro and in vivo defects, resulting in variable deficiencies in thymic development and in T cell antigen receptor (TCR) signal transduction, in PTKs have been shown. ZAP70, one of those PTKs, is a 70-kDa tyrosine phosphoprotein and associates with the ζ chain and undergoes tyrosine phosphorylation following TCR stimulation. It is expressed in T and natural killer (NK) cells. Several mutations were shown to lead to an autosomal recessive form of severe combined immunodeficiency disease (SCID). 相似文献
62.
In this report we describe the first patient ever found to have azoospermia in association with both exceptional complex chromosomal rearrangements and microdeletions at two translocation breakpoints. A 36-year-old male who had been suffering from male factor infertility was admitted to our clinic. The patient also displayed mild dysmorphia. An analysis of the patient's semen revealed azoospermia. GTG banding revealed the presence of an exceptional complex chromosomal rearrangement involving chromosomes 1, 4, 10 and 14. Using subtelomeric FISH analysis, the patient's karyotype was designated as 46,XY,t(1;10)(q43q44;q21q26.1)(CEB108/T7+,D1S3738-;10PTEL006+,D10S2290+, D1S3738+), ins(14;4) (q31.3;q23q33)(D14S1420+; D4S3359+, D4S2930+). Array-CGH analysis revealed two microdeletions at the 4q22.3q23 and 14q31.1q31.3 chromosomal regions. We suggest that microdeletions at the 4q22.3q23 and 14q31.1q31.3 chromosomal regions associated with both an exceptional complex chromosomal rearrangement and the Homo sapiens chromosome 4 open reading frame 37 (C4orf37) gene located at the 4q22.3q23 region might be associated with male factor infertility. 相似文献
63.
Hemoglobin (Hb), an oxygen‐binding protein composed of four subunits (α1, α2, β1, and β2), is a well‐known example of allosteric proteins that are capable of cooperative ligand binding. Despite decades of studies, the structural basis of its cooperativity remains controversial. In this study, we have integrated coarse‐grained (CG) modeling, all‐atom simulation, and structural data from X‐ray crystallography and wide‐angle X‐ray scattering (WAXS), aiming to probe dynamic properties of the two structural states of Hb (T and R state) and the transitions between them. First, by analyzing the WAXS data of unliganded and liganded Hb, we have found that the structural ensemble of T or R state is dominated by one crystal structure of Hb with small contributions from other crystal structures of Hb. Second, we have used normal mode analysis to identify two distinct quaternary rotations between the α1β1 and α2β2 dimer, which drive the transitions between T and R state. We have also identified the hot‐spot residues whose mutations are predicted to greatly change these quaternary motions. Third, we have generated a CG transition pathway between T and R state, which predicts a clear order of quaternary and tertiary changes involving α and β subunits in Hb. Fourth, we have used the accelerated molecular dynamics to perform an all‐atom simulation starting from the T state of Hb, and we have observed a transition toward the R state of Hb. Further analysis of crystal structural data and the all‐atom simulation trajectory has corroborated the order of quaternary and tertiary changes predicted by CG modeling. Proteins 2013. © 2012 Wiley Periodicals, Inc. 相似文献
64.
Mustafa Hasbahceci Gokhan Cipe Huseyin Kadioglu Erhan Aysan Mahmut Muslumanoglu 《Biological trace element research》2013,153(1-3):141-144
The exact role of boron in humans is not known although its supplementation causes several important metabolic and inflammatory changes. The objective of this study is to evaluate the possibility of an association between blood boron level and obesity in normal, overweight, obese, and morbidly obese subjects. A total number of 80 subjects, categorized into four groups based on their body mass index as normal, overweight, obese, and morbidly obese, were enrolled in this study. Age, sex, body mass index, and blood boron levels were recorded for each subject. Although the distribution of female and male subjects and blood boron levels were similar between groups, the mean age of normal subjects was significantly lower than the others (p?=?0.002). There was a significant relationship between age and quantitative values of body mass index for each subject (β?=?0.24; p?=?0.003). In addition, between blood boron levels and quantitative values of body mass index for each subject, a significant reverse relationship was detected (β?=??0.16; p?=?0.043). Although age seemed to be an important variable for blood boron level and body mass index, blood boron levels were shown to be lower in obese subjects in comparison to non-obese subjects. 相似文献
65.
In the present study the biofilm-forming characteristics of 99 serotyped (DMC strains) and 41 genus level-identified (IS strains) Salmonella strains originating from Turkey were investigated. The strains were selected based on their ability to show the biofilm morphotype on Congo red agar plates. In addition, all strains were evaluated with regard to properties related to forming pellicle structures, physical differences of pellicles, any changes in the media associated with the formation of pellicles, and the presence of cellulose within the formed biofilm matrix as determined using 366 nm UV light. The Salmonella Typhimurium DMC4 strain was the best producer of biofilm grown on polystyrene microtiter plates (optical density at 595 nm: 3.418). In subsequent experiments industrial process conditions were used to investigate different morphotyped Salmonella strains’ biofilm-forming capability on stainless steel, a commonly preferred surface for the food industries, and on polystyrene surfaces. The effect of other important industrial conditions, such as temperature (5, 20, 37°C), pH (4.5, 5.5, 6.5, 7.4) and NaCl concentration (0.5, 1.5, 5.5, 10.5%) on the production of biofilm of the different morphotyped Salmonella strains (DMC4; red, dry and rough morphotyped S. Typhimurium, DMC12; brown, dry and rough morphotyped S. Infantis, DMC13; pink, dry and rough morphotyped S. subsp. Roughform) were also assessed. On the other hand, pH values exhibited variable effects on biofilm-forming features for different Salmonella strains on both polystyrene and stainless steel surfaces. 相似文献
66.
Havva Balseven M. Mustafa İşgör Samet Mert Zuhal Alım Şükrü Beydemir Salim Ok Rahmi Kasımoğulları 《Bioorganic & medicinal chemistry》2013,21(1):21-27
In the current study, a series of pyrazole-sulfonamide derivatives (2–14) were synthesized, characterized, and the inhibition effects of the derivatives on human carbonic anhydrases (hCA I and hCA II) were investigated as in vitro. Structures of these sulfonamides were confirmed by FT-IR, 1H NMR, 13C NMR and LC–MS analysis. 1H NMR and 13C NMR revealed the tautomeric structures. hCA I and hCA II isozymes were purified from human erythrocytes and inhibitory effects of newly synthesized sulfonamides on esterase activities of these isoenzymes have been studied. The Ki values of compounds were 0.062–1.278 μM for hCA I and 0.012–0.379 μM for hCA II. The inhibition effects of 7 for hCA I and 4 for hCA II isozymes were almost in nanomolar concentration range. 相似文献
67.
Mustafa Raoof Brandon T. Cisneros Stuart J. Corr Flavio Palalon Steven A. Curley Nadezhda V. Koshkina 《PloS one》2013,8(7)
There is a renewed interest in developing high-intensity short wave capacitively-coupled radiofrequency (RF) electric-fields for nanoparticle-mediated tumor-targeted hyperthermia. However, the direct thermal effects of such high-intensity electric-fields (13.56 MHZ, 600 W) on normal and tumor tissues are not completely understood. In this study, we investigate the heating behavior and dielectric properties of normal mouse tissues and orthotopically-implanted human hepatocellular and pancreatic carcinoma xenografts. We note tumor-selective hyperthermia (relative to normal mouse tissues) in implanted xenografts that can be explained on the basis of differential dielectric properties. Furthermore, we demonstrate that repeated RF exposure of tumor-bearing mice can result in significant anti-tumor effects compared to control groups without detectable harm to normal mouse tissues. 相似文献
68.
Sharifah Nurain Syed Zanaruddin Pei San Yee Seen Yii Hor Yink Heay Kong Wan Maria Nabillah Wan Abd Ghani Wan Mahadzir Wan Mustafa Rosnah Binti Zain Stephen S. Prime Zainal Ariff Abd Rahman Sok-Ching Cheong 《PloS one》2013,8(11)
Objectives
The frequency of common oncogenic mutations and TP53 was determined in Asian oral squamous cell carcinoma (OSCC).Materials and Methods
The OncoCarta™ panel v1.0 assay was used to characterize oncogenic mutations. In addition, exons 4-11 of the TP53 gene were sequenced. Statistical analyses were conducted to identify associations between mutations and selected clinico-pathological characteristics and risk habits.Results
Oncogenic mutations were detected in PIK3CA (5.7%) and HRAS (2.4%). Mutations in TP53 were observed in 27.7% (31/112) of the OSCC specimens. Oncogenic mutations were found more frequently in non-smokers (p = 0.049) and TP53 truncating mutations were more common in patients with no risk habits (p = 0.019). Patients with mutations had worse overall survival compared to those with absence of mutations; and patients who harbored DNA binding domain (DBD) and L2/L3/LSH mutations showed a worse survival probability compared to those patients with wild type TP53. The majority of the oncogenic and TP53 mutations were G:C > A:T and A:T > G:C base transitions, regardless of the different risk habits.Conclusion
Hotspot oncogenic mutations which are frequently present in common solid tumors are exceedingly rare in OSCC. Despite differences in risk habit exposure, the mutation frequency of PIK3CA and HRAS in Asian OSCC were similar to that reported in OSCC among Caucasians, whereas TP53 mutations rates were significantly lower. The lack of actionable hotspot mutations argue strongly for the need to comprehensively characterize gene mutations associated with OSCC for the development of new diagnostic and therapeutic tools. 相似文献69.