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Y. Chen B. Bai H. Yan F. Wen D. Qin G. Jander Q. Xia G. Wang 《Insect molecular biology》2019,28(3):380-391
Isopentenylation at A37 (i6A37) of some transfer RNAs (tRNAs) plays a vital role in regulating the efficiency and fidelity of protein synthesis. However, whether insects, which are well known for their highly efficient protein synthesis machinery, employ this regulatory mechanism remains uninvestigated. In the current study, a candidate tRNA isopentenyltransferase (IPT) gene with three alternative splicing isoforms (BmIPT1–BmIPT3) was identified in Bombyx mori (silkworm). Only BmIPT1 could complement a yeast mutant lacking tRNA IPT. Phylogenetic analysis showed that silkworm tRNA IPT is conserved in the Lepidoptera. BmIPT was expressed in all B. mori tissues and organs that were investigated, but was expressed at a significantly higher level in silk glands of the fourth instar compared to the first day of the fifth instar. Interestingly, BmIPT was expressed at a significantly higher level in the domesticated silkworm, B. mori, than in wild Bombyx mandarina in multiple tissues and organs. Knock‐down of BmIPT by RNA interference caused severe abnormalities in silk spinning and metamorphosis. Constitutive overexpression of BmIPT1 using a cytoplasmic actin 4 promoter in B. mori raised its messenger RNA level more than sixfold compared with nontransgenic insects and led to significant decreases in the body weight and cocoon shell ratio. Together, these results confirm the first functional tRNA IPT in insects and show that a suitable expression level of tRNA IPT is vital for silk spinning, normal growth, and metamorphosis. Thus, i6A modification at position A37 in tRNA probably plays an important role in B. mori protein synthesis. 相似文献
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Xian-Hua Han Xiu-Ming Li Wei-Jun Tang Huan Yu Ping Wu Jing-Jie Ge Jian Wang Chuan-Tao Zuo Kuang-Yu Shi 《中国神经再生研究》2019,(5)
Idiopathic rapid eye movement sleep behavior disorder(iRBD) is often a precursor to neurodegenerative disease. However, voxel-based morphological studies evaluating structural abnormalities in the brains of iRBD patients are relatively rare. This study aimed to explore cerebral structural alterations using magnetic resonance imaging and to determine their association with clinical parameters in iRBD patients. Brain structural T1-weighted MRI scans were acquired from 19 polysomnogram-confirmed iRBD patients(male:female 16:3; mean age 66.6 ± 7.0 years) and 20 age-matched healthy controls(male:female 5:15; mean age 63.7 ± 5.9 years). Gray matter volume(GMV) data were analyzed based on Statistical Parametric Mapping 8, using a voxel-based morphometry method and two-sample t-test and multiple regression analysis. Compared with controls, iRBD patients had increased GMV in the middle temporal gyrus and cerebellar posterior lobe, but decreased GMV in the Rolandic operculum, postcentral gyrus, insular lobe, cingulate gyrus, precuneus, rectus gyrus, and superior frontal gyrus. iRBD duration was positively correlated with GMV in the precuneus, cuneus, superior parietal gyrus, postcentral gyrus, posterior cingulate gyrus, hippocampus, lingual gyrus, middle occipital gyrus, middle temporal gyrus, and cerebellum posterior lobe. Furthermore, phasic chin electromyographic activity was positively correlated with GMV in the hippocampus, precuneus, fusiform gyrus, precentral gyrus, superior frontal gyrus, cuneus, inferior parietal lobule, angular gyrus, superior parietal gyrus, paracentral lobule, and cerebellar posterior lobe. There were no significant negative correlations of brain GMV with disease duration or electromyographic activity in iRBD patients. These findings expand the spectrum of known gray matter modifications in iRBD patients and provide evidence of a correlation between brain dysfunction and clinical manifestations in such patients. The protocol was approved by the Ethics Committee of Huashan Hospital(approval No. KY2013-336) on January 6, 2014. This trial was registered in the ISRCTN registry(ISRCTN18238599). 相似文献
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Yücel Yüzbaşıoğlu Gülşah Çıkrıkçı Işık 《The American journal of emergency medicine》2019,37(9):1691-1693
IntroductionThe aim of this study was to compare the distribution and frequency of forensic medical events in a refugee group with that of the general population, and thus, extrapolate the problems encountered in the immigrant population.MethodsThose cases admitted to the emergency department (ED) for any reason that required a forensic examination between January 2016 and June 2018 were investigated retrospectively.ResultsA total of 310 refugees were admitted to the ED for forensic medical events. The most common nations of origin of the refugees were Iraq (n = 167), Syria (n = 65), and Afghanistan (n = 28). The median age of the refugees was 24 years old (interquartile range = 17–33). With regard to forensics, the most common reasons for the refugees to present to the ED were motor vehicle accidents 27.4%, assaults 25.8%, employment and industrial accidents 16.1%, and suicide attempts 10.3%. Other than suicide attempts, all of the forensic presentations were more common in the males. The outcomes of the refugee group were as follows: 92.3% were discharged, 5.8% were admitted to the hospital, 1% were admitted to the intensive care unit (ICU), and 1% were transferred. Suicide attempts were the most common reasons for the ICU admissions, while the most common reasons for the hospital admissions were orthopedic injuries.ConclusionIn general, the forensic event frequency in the refugee group was lower (p = 0.001); however, this was a single center study, and there could have been unrecorded cases due to an inability to access healthcare assistance, so these results may not be reliable. 相似文献
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Michelle Y L Tang Patrick H Y Chung Hau Y Chan Paul K H Tam Kenneth KY Wong 《Journal of pediatric surgery》2019,54(2):255-257
Objective
Helicobacter pylori infection is common among Asians. However, evidence in the recent years has demonstrated a decrease in the prevalence of H. pylori infection among children and adults worldwide. Our aim was to update its prevalence in symptomatic children in our locality in the recent 12?years and compared to the results of our previous review published in 2005.Methods
A retrospective review was carried out between 2005 and 2017. All children who presented with dyspepsia or gastrointestinal bleeding and underwent oesophagogastroduodenoscopy with antral biopsy taken were included. Patient demographics, endoscopic, or histological diagnosis and the H. pylori status were recorded.Main Results
A total of 602 patients were included. There was a statistically significant decreasing trend of H. pylori infection rate between 2005 and 2017 (p?=?0.003). The overall infection rate from this study was 12.8%, compared to 25.6% from our previous review. Overall failure of eradication with first-line antibiotic therapy has increased to 29.3% from 10% in our previous review.Conclusion
There was a decrease in the prevalence of H. pylori infection among symptomatic children for the recent 12?years, comparing to our previous data from 2005. We hypothesize that the reduction in prevalence of H. pylori infection among adults and the decrease in the practice of sharing chopsticks during meals have led to a decrease in transmission of the bacteria among family members in Hong Kong. However, the failure of eradication with first line treatment was higher, possibly due to the increase in antibiotics usage and resistance.Level of Evidence
III 相似文献68.
BackgroundWomen suffering from kidney disease are more prone to fertility problems, due to uremia. Fortunately, their fertility rate increases dramatically after renal transplantation. This study analyzes the predictors/risk factors of successful pregnancy with live birth outcome while presenting an overview of the 7-year experience of a single center.MethodsThis retrospective cohort study includes 239 women of reproductive age (18–40 years) who underwent renal transplantation in a tertiary Turkish clinic between October 1, 2011, and August 24, 2017. The subjects were invited to take part in a survey questioning their obstetric characteristics and they were assessed in 2 groups: fertile and infertile. Multivariable linear regression analysis was conducted to determine the predictors of a successful pregnancy.ResultsThirty-five 35 patients wished to become pregnant: 12 got pregnant spontaneously, while 21 failed to become pregnant (spontaneously). The mean age of the patients at the survey was 34 ± 7. Regular menstrual cycles after renal transplantation, tacrolimus-mycophenolate mofetil maintenance protocol, and age at transplantation were found to be predictors of spontaneous pregnancy. The duration of peritoneal dialysis was significantly longer in the infertile group (48 vs 12 months).ConclusionEnd-stage renal disease's negative impacts, including menstrual abnormality and fertility problems, can be overcome by successful kidney transplantation with appropriate immunosuppression. Minimizing the duration of peritoneal dialysis, particularly in patients who desire future fertility, may be accepted as a logical management strategy. 相似文献
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Ingigerður S. Sverrisdóttir Sigrún H. Lund Ingemar Turesson Magnus Björkholm Lynn R. Goldin Ola Landgren Sigurður Y. Kristinsson 《British journal of haematology》2019,186(1):37-44
Parental longevity is associated with an increased life expectancy; results with regard to specific diseases are conflicting. There are limited data focusing on host characteristics and their effect on survival among multiple myeloma (MM) patients and individuals with monoclonal gammopathy of undetermined significance (MGUS). Therefore, our aim was to evaluate the impact of parental longevity on survival of patients with MM and MGUS. A total of 4675 patients with MM, 6812 MGUS patients and 13 398 population-based controls for MM as well as 19 110 controls for MGUS, from 1988 to 2013, were included in the study. Longevity was defined as >90 years of age. Among MM patients, parental longevity was associated with a decreased risk of death [hazard ratio (HR) = 0·92, 95% confidence interval (CI) 0·84–0·99] and the same was true for MGUS patients (HR = 0·87, 95% CI 0·78–0·96). Having one long lived parent significantly decreased the risk of death in both groups, but was not statistically significant when both parents exceeded 90 years of age. In conclusion, parental longevity decreases the risk of death for patients with MM and MGUS which may reflect the importance of the host's genetic and environmental factors in relation to survival. 相似文献