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31.
Florian Stengel Andrew J. Baldwin Alexander J. Painter Nomalie Jaya Eman Basha Lewis E. Kay Elizabeth Vierling Carol V. Robinson Justin L. P. Benesch 《Proceedings of the National Academy of Sciences of the United States of America》2010,107(5):2007-2012
Small Heat Shock Proteins (sHSPs) are a diverse family of molecular chaperones that prevent protein aggregation by binding clients destabilized during cellular stress. Here we probe the architecture and dynamics of complexes formed between an oligomeric sHSP and client by employing unique mass spectrometry strategies. We observe over 300 different stoichiometries of interaction, demonstrating that an ensemble of structures underlies the protection these chaperones confer to unfolding clients. This astonishing heterogeneity not only makes the system quite distinct in behavior to ATP-dependent chaperones, but also renders it intractable by conventional structural biology approaches. We find that thermally regulated quaternary dynamics of the sHSP establish and maintain the plasticity of the system. This extends the paradigm that intrinsic dynamics are crucial to protein function to include equilibrium fluctuations in quaternary structure, and suggests they are integral to the sHSPs’ role in the cellular protein homeostasis network. 相似文献
32.
Mervat M El-Eshmawy Eman H El-Adawy Amany A Mousa Amany E Zeidan Azza A El-Baiomy Elham R Abdel-Samie Omayma M Saleh 《BMC women's health》2011,11(1):1
Background
Neutrophil elastase level/activity is elevated in a variety of diseases such as atherosclerosis, systolic hypertension and obstructive pulmonary disease. It is unknown whether obese individuals with prehypertension also have elevated neutrophil elastase, and if so, whether it has a deleterious effect on pulmonary function. Objectives: To determine neutrophil elastase levels in obese prehypertensive women and investigate correlations with pulmonary function tests. 相似文献33.
Objectives
To evaluate the safety of using the stiff end of a coronary wire to perforate an atretic pulmonary valve (PV) in patients with pulmonary atresia with intact ventricular septum (PAIVS).Background
Radiofrequency perforation is an accepted modality to perforate the PV in patients PAIVS. However, the high cost precludes its widespread use.Patients and methods
This is a single-center experience that spanned from March 2013 to January 2016 and involved 13 neonates who were severely cyanotic with PAIVS and with ductal-dependent pulmonary circulation. The stiff end of a coronary wire was used to perforate the atretic PV anterogradely, followed by balloon pulmonary valvuloplasty.Results
The mean age of patients was 3.9?±?2.7?days and their mean weight was 2.8?±?0.19?kg. The mean oxygen saturation was 77.1?±?3.2%. All had membranous pulmonary atresia, with patent infundibulum and tripartite right ventricle. The valve was successfully perforated in 11 out of 13 patients. Death occurred in two patients (15.4%) owing to heart failure and sepsis. Patent ductus arteriosus stenting was performed 2?days after the procedure in one patient because of cyanosis followed by one and half ventricle repair at of age 5?months. Two patients (15.4%) had one and a half ventricle repair at age of 5?months and 6?months owing to insufficient anterograde pulmonary flow. Two patients (15.4%) underwent second intervention with balloon dilatation of the valve. The remaining seven patients (53.8%) had no further intervention. Two cases (15.4%) had femoral artery thrombosis treated with streptokinase. The mean duration of follow-up was 13.17?±?7?months. There was significant improvement in the degree of tricuspid incompetence. There was a significant growth in the tricuspid valve annulus during the follow-up (the mean Z score increased from ?0.8?±?0.9 to 0.1?±?0.9) (p?=?0.003). There was also a significant increase in the tricuspid valve annulus/mitral valve annulus ratio as its mean increased from 0.73?±?0.10 to 0.86?±?0.11 during follow-up (p?<?0.001).Conclusion
Perforation of the atretic PV in selected cases with membranous atresia and patent infundibulum using the stiff end of a coronary wire is an effective alternative to using radiofrequency perforation. 相似文献34.
Nihal Fathi Samar H. Goma Nadia M. Ismail Abeer M. Ghandour Sally S. Youssef Nisreen A. Mohammed Eman Mosad 《The Egyptian Rheumatologist》2018,40(1):45-49
Background
Systemic sclerosis (SSc) is an autoimmune connective tissue disease with vascular, fibrotic and immune changes of skin and some internal organs. Anti-heterogeneous nuclear ribonucleoproteins (anti-hnRNP) were found in SSc patients.Aim of the work
To assess anti-hnRNP A1 and A2 autoantibodies in limited SSc patients and to find their relation to clinical and hand radiographic characteristics.Patients and methods
26 limited SSc patients and 16 matched control were studied. Skin thickness was scored according to the modified Rodnan skin score method (mRss) and radiologic examination by plain X-ray of the hand and wrist was performed anti-hnRNP A1 and A2 were measured in patients and control.Results
All patients were females with a mean age of 37.5 ± 11.24 years and mean disease duration of 7.84 ± 1.19 years. 96.2% of cases showed juxta-articular osteoporosis, 38.5% with marginal erosions, 73.1% with surface erosions, 42.3% with subchondral cyst, 42.3% with metacarpophalangeal subluxation, 11.5% with marginal sclerosis, 80.8% with resorption of distal phalanges, 38.5% with resorption of distal ulna and 34.6% with calcinosis. Anti-hnRNPA1 was positive in all the patients but the anti-hnRNPA2 was positive in 21 (80.8%). Anti-hnRNP A1 and A2 showed significant difference between patients and control (5.66 ± 4.18 ng/ml vs 2.88 ± 0.82; p < 0.01 and 1.82 ± 0.36 vs 0.73 ± 0.08; p < 0.02, respectively). There was no significant correlation between the markers with the mRss or radiographic changes.Conclusion
Joint affection in SSc is more frequent than expected. Anti-hnRNP A1 and anti hnRNP A2 antigens may be useful markers for SSc patient although no significant relation was found with radiologic findings. 相似文献35.
Naiema K. Ali Ragaa R. Mohamed Bothina E. Saleh Manal M. Alkady Eman S. Farag 《Arab Journal Of Gastroenterology》2018,19(3):101-105
Background and study aims
Hepatitis C virus (HCV) infection is a severe problem among patients on maintenance haemodialysis who are at particular risk for blood-borne infections because of prolonged vascular access and potential for exposure to contaminated equipment. Occult hepatitis C virus infection (OCI) is defined as the presence of HCV RNA in liver or peripheral blood mononuclear cells (PBMCs) in the absence of detectable HCV antibody or HCV RNA in the serum. In this study, we aimed to investigate the existence of occult hepatitis C virus infection in PBMCs of haemodialysis (HD) patients in one center. Moreover, we tried to link the condition to risk factors associated with HCV infection in those patients.Patients and methods
We included 40 patients with renal diseases undergoing regular haemodialysis who were repeatedly anti-HCV negative. HCV RNA detection was tested by Quantitative Real time PCR in serum and PBMCs.Results
The results of this study revealed that 23% of our haemodialysis patients have occult hepatitis C virus infection. There was a highly significant increase in ALT levels in patients with OCI versus the negative group. Also, there is a significant increase of history of blood transfusion in patients with occult HCV (p?=?0.03) while the duration of haemodialysis showed no statistical significant difference between both groups. The viral load of the occult hepatitis C virus infection subjects ranged from 581to 74,307 copies/ml.Conclusion
These results highlight the potential risk of hepatitis C virus transmission from patients within haemodialysis units in Egypt. Isolation of patients on dialysis machines depending on the results of hepatitis serological markers is not enough. Testing for hepatitis C virus -RNA in peripheral blood mononuclear cells is more reliable in identifying patients with an OCI when a liver biopsy is not available. 相似文献36.
eHanaa Mostafa El-Karaksy Nehal Mohammad El-Koofy Rokaya El-Sayed Mona Al-Saeed El-Raziky Samah Asaad Mansour 《World journal of gastroenterology : WJG》2006,(45)
INTRODUCTION Hepatitis A virus (HAV) infection is common. In general, hepatitis A is a self-limited illness with a recovery time measured in months[1]. Young children are often asymptomatic, whereas adults are more likely to be symptomatic and may present… 相似文献
37.
Tawfiq M. Al Antary Hussein Estityah Nizar Haddad Eman T. Al-Antary 《Toxin reviews》2015,34(4):190-194
Chlorinated pesticide residues in human breast milk from five southern Jordan districts were analyzed in 2012/2013. The total number of samples from all districts was 100. The number of samples gathered from each district was collected according to their population densities. The present study shows that 59% of the samples which contained pesticides’ residues were p,p’-DDE, 30% contained β-HCH, 10% contained p,p′-DDT, 6% contained α-HCH, 2% contained heptachlor and 1% contained endrin. These human milk samples were free of aldrin, dieldrin, α-endosulfan, β-endosulfan, HCB, γ-HCH, o,p′-DDD, o,p′-DDT and o,p′-DDE. The levels of the six mentioned compounds detected in all mother’s milk samples were higher in Ghor El-Safi district compared with the other four districts. In this study, it is recommended to continue the pesticides residues monitoring in all parts of Jordan, particularly in Ghor El-Safi district and other regions in the cultivated Jordan Valley. 相似文献
38.
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40.
Ghada Asaad Maryam Sadegian Rita Lau Yunke Xu Diana C. Soria-Contreras Rhonda C. Bell Catherine B. Chan 《Nutrients》2015,7(7):5484-5496
Nutrition therapy is essential for diabetes treatment, and assessment of dietary intake can be time consuming. The purpose of this study was to develop a reliable and valid instrument to measure diabetic patients’ adherence to Canadian diabetes nutrition recommendations. Specific information derived from three, repeated 24-h dietary recalls of 64 type 2 diabetic patients, aged 59.2 ± 9.7 years, was correlated with a total score and individual items of the Perceived Dietary Adherence Questionnaire (PDAQ). Test-retest reliability was completed by 27 type 2 diabetic patients, aged 62.8 ± 8.4 years. The correlation coefficients for PDAQ items versus 24-h recalls ranged from 0.46 to 0.11. The intra-class correlation (0.78) was acceptable, indicating good reliability. The results suggest that PDAQ is a valid and reliable measure of diabetes nutrition recommendations. Because it is quick to administer and score, it may be useful as a screening tool in research and as a clinical tool to monitor dietary adherence. 相似文献