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91.
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Innokentiy S. Losenkov Natalya M. Vyalova German G. Simutkin Nikolay A. Bokhan Svetlana A. Ivanova 《The world journal of biological psychiatry》2016,17(3):239-242
Objectives: Nowadays it is considered that protein kinase Akt1 could be involved in pathogenesis of affective disorders. We have examined whether AKT1 gene polymorphisms are associated with antidepressant treatment response. Methods: The study included 106 Caucasian patients with depressive disorders from Siberia and 103 healthy control donors. The frequencies of single nucleotide polymorphisms rs1130214 and rs3730358 of AKT1 gene were examined. Results: A comparison of genotypic or allelic frequencies between the groups of healthy donors and depressive patients showed no statistically significant difference. No association between the polymorphisms under study and the scores according to Hamilton Depression Rating Scale 17 was found. However, an association between treatment response assessed by the Clinical Global Impression – Improvement scale and rs1130214 polymorphism was observed. Conclusions: AKT1 gene polymorphism rs1130214 is associated with antidepressant treatment response in patients with depressive disorders. 相似文献
93.
Challenges in Patient Enrollment and Retention in Clinical Studies for Alcoholic Hepatitis: Experience of the TREAT Consortium 下载免费PDF全文
Megan Comerford Spencer Lourens Suthat Liangpunsakul Naga P. Chalasani Arun J. Sanyal Vijay H. Shah Patrick S. Kamath Puneet Puri Barry P. Katz Svetlana Radaeva David W. Crabb 《Alcoholism, clinical and experimental research》2017,41(12):2000-2006
The TREAT Consortium has carried out clinical studies on alcoholic hepatitis (AH) for over 4 years. We encountered problems with participant recruitment, retention, and eligibility for specific protocols. To improve our ability to carry out such trials, we reviewed recruitment screening logs, end of study logs, and surveyed study coordinators to learn the reasons for missing patients, why patients declined enrollment, and the number of patients eligible for treatment trials. Associations of the recruited subjects’ demographics with their adherence to follow‐up appointments were examined. Three hundred eight‐seven patients (AH and heavy drinking controls) were enrolled in the observational study, and 55 AH patients were recruited into treatment trials. About half of patients identified with AH could not be recruited; no specific reason could be determined for about two‐thirds of these. Among the patients who gave a reason for not participating, the most common reasons were feeling too sick to participate, desire to concentrate on abstinence, and lack of interest in research. Approximately a quarter of the AH patients met eligibility criteria for treatment trials for moderate or severe AH and we were able to recruit half to two‐thirds of those eligible. Approximately 35% of participants in the observational study returned for both 6‐ and 12‐month follow‐up visits. We did not identify biopsychosocial or demographic correlates of retention in the study. This analysis revealed that attempts at recruitment into trials for AH miss some subjects because of structural issues surrounding their hospital admission, and encounter a high rate of patient refusal to participate. Nonetheless, more than half of the patients who met the eligibility criteria for moderate or severe AH were entered into clinical trials. Retention rates for the observational study are relatively low. These findings need to be accounted for in clinical trial design and power analysis. 相似文献
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Evgeny N Imyanitov Ekaterina S Kuligina Anna P Sokolenko Evgeny N Suspitsin Grigoriy A Yanus Aglaya G Iyevleva Alexandr O Ivantsov Svetlana N Aleksakhina 《World journal of clinical oncology》2023,14(2):40-68
Hereditary cancer syndromes(HCSs) are arguably the most frequent category of Mendelian genetic diseases, as at least 2% of presumably healthy subjects carry highly-penetrant tumor-predisposing pathogenic variants(PVs). Hereditary breast-ovarian cancer and Lynch syndrome make the highest contribution to cancer morbidity; in addition, there are several dozen less frequent types of familial tumors. The development of the majority albeit not all hereditary malignancies involves two-hit mechanism, i.... 相似文献
96.
Timofey M. Karnaukhov Grigory B. Veselov Svetlana V. Cherepanova Aleksey A. Vedyagin 《Materials》2022,15(6)
A sol-gel technique was applied to prepare the two-component oxide system Cu-Mg-O, where MgO plays the role of oxide matrix, and CuO is an active chemical looping component. The prepared samples were characterized by scanning electron microscopy, low-temperature nitrogen adsorption, and X-ray diffraction analysis. The reduction behavior of the Cu-Mg-O system was examined in nine consecutive reduction/oxidation cycles. The presence of the MgO matrix was shown to affect the ability of CuO towards reduction and re-oxidation significantly. During the first reduction/oxidation cycle, the main characteristics of the oxide system (particle size, crystallization degree, etc.) undergo noticeable changes. Starting from the third cycle, the system exhibits a stable operation, providing the uptake of similar hydrogen amounts within the same temperature range. Based on the obtained results, the two-component Cu-Mg-O system can be considered as a prospective chemical looping agent. 相似文献
97.
Konstantin Andryushin Svetlana Dudkina Sushrisangita Sahoo Lidiya Shilkina Vladimir Alyoshin Ekaterina Triger Inna Andryushina Iliya Verbenko Daniil Rudskiy Angela Rudskaya Larisa Reznichenko 《Materials》2022,15(6)
Ferro-piezoceramic materials (FPCM) with different degrees of ferrohardness were fabricated by double solid-phase synthesis followed by the sintering technique using hot pressing method. The X-ray studies carried out in a wide temperature range showed that with increasing temperature, each of the studied FPCM undergoes a series of phase transformations, accompanied by a change in the symmetry of the unit cell. In this case, near the phase transition to the nonpolar cubic phase, in each of the FPCM, the formation of a fuzzy symmetry region is observed, which is characterized by weak distortions and temperature–time instability of the crystal structure. The study of the piezoelectric modulus d33 in the quasi-static regime as a function of temperature made it possible to reveal the different nature of its behavior in materials of various degrees of ferrohardness. It was shown that the conservation of the state in ferrosoft materials above the Curie temperature is associated with the relaxation nature of the change in their properties, the existence of a region of fuzzy symmetry (noncubic phase) in them above the Curie temperature, and increased inertia of the system. The expediency of taking into account the presented results in the development of electromechanical converters based on FPCM of various degrees of ferrohardness, operated under temperature effects, including cyclic ones, was shown. 相似文献
98.
99.
In vivo identification of genes that modify ether-a-go-go-related gene activity in Caenorhabditis elegans may also affect human cardiac arrhythmia 下载免费PDF全文
Petersen CI McFarland TR Stepanovic SZ Yang P Reiner DJ Hayashi K George AL Roden DM Thomas JH Balser JR 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(32):11773-11778
Human ether-a-go-go-related gene (HERG) encodes the pore-forming subunit of I(Kr), a cardiac K(+) channel. Although many commonly used drugs block I(Kr), in certain individuals, this action evokes a paradoxical life-threatening cardiac rhythm disturbance, known as the acquired long QT syndrome (aLQTS). Although aLQTS has become the leading cause of drug withdrawal by the U.S. Food and Drug Administration, DNA sequencing in aLQTS patients has revealed HERG mutations only in rare cases, suggesting that unknown HERG modulators are often responsible. By using the worm Caenorhabditis elegans, we have developed in vivo behavioral assays that identify candidate modulators of unc-103, the worm HERG orthologue. By using RNA-interference methods, we have shown that worm homologues of two HERG-interacting proteins, Hyperkinetic and K channel regulator 1 (KCR1), modify unc-103 function. Examination of the human KCR1 sequence in patients with drug-induced cardiac repolarization defects revealed a sequence variation (the substitution of isoleucine 447 by valine, I447V) that occurs at a reduced frequency (1.1%) relative to a matched control population (7.0%), suggesting that I447V may be an allele for reduced aLQTS susceptibility. This clinical result is supported by in vitro studies of HERG dofetilide sensitivity by using coexpression of HERG with wild-type and I447V KCR1 cDNAs. Our studies demonstrate the feasibility of using C. elegans to assay and potentially identify aLQTS candidate genes. 相似文献
100.
Larisa Rudenko Julia Desheva Sergey Korovkin Alexander Mironov Andrey Rekstin Elena Grigorieva Svetlana Donina Alexandra Gambaryan Anton Katlinsky 《Influenza and other respiratory viruses》2008,2(6):203-209
Objective Our studies aimed to evaluate in clinical trials the safety and immunogenicity of an H5 live influenza vaccine candidate obtained using classical reassortment techniques from a low pathogenicity avian influenza (LPAI) A/Duck/Potsdam/1402‐6/86(H5N2) virus and the cold‐adapted (ca) donor strain A/Leningrad/134/17/57(H2N2). Methods During Phase I–II clinical trials, volunteers received intranasally two doses of reassortant influenza vaccine strain A/17/Duck/Potsdam/86/92 (H5N2) 21 days apart. Clinical examination of all vaccinees was conducted 7 days post‐vaccination. Serum antibody responses were measured by hemagglutination‐inhibition and microneutralization and local antibodies were estimated using an enzyme‐linked immunosorbent assay test. Results The vaccine was safe and of low reactogenicity with no febrile reactions. After revaccination 47·1–54·8% of subjects showed ≥fourfold seroconversions of Hamagglutination inhibition (HAI) antibodies to the hemagglutinin (HA) antigen of the A/17/Duck/Potsdam/86/92 (H5N2) virus and 29·4–30·8% were seroconverted to the HA antigen of the reverse genetics reassortant A/Indonesia/05/2005 × PR8 IBCDC‐RG (H5N1). Virus‐neutralizing antibody levels in sera of volunteers were similar to those shown in HAI test. The virus‐specific nasal IgA antibody response after two vaccine doses demonstrated significant increases of ≥fourfold rise SIgA antibodies (65%) geometrical mean titers (16·0) and a rise in SIgA antibodies (2·8) compared with one dose. Conclusion The live attenuated influenza vaccine candidate prepared using the LPAI A(H5N2) strain was well tolerated and elicited serum and local immune responses. There was evident cross‐reactivity to the A(H5N1) strain in the HAI test. 相似文献