Quality control mechanisms during translation

Translation uses the genetic information in messenger RNA (mRNA) to synthesize proteins. Transfer RNAs (tRNAs) are charged with an amino acid and brought to the ribosome, where they are paired with the corresponding trinucleotide codon in mRNA. The amino acid is attached to the nascent polypeptide and the ribosome moves on to the next codon. The cycle is then repeated to produce a full-length protein. Proofreading and editing processes are used throughout protein synthesis to ensure the faithful translation of genetic information. The maturation of tRNAs and mRNAs is monitored, as is the identity of amino acids attached to tRNAs. Accuracy is further enhanced during the selection of aminoacyl-tRNAs on the ribosome and their base pairing with mRNA. Recent studies have begun to reveal the molecular mechanisms underpinning quality control and go some way to explaining the phenomenal accuracy of translation first observed over three decades ago.     

Impaired respiratory and body temperature control upon acute serotonergic neuron inhibition

Physiological homeostasis is essential for organism survival. Highly responsive neuronal networks are involved, but their constituent neurons are just beginning to be resolved. To query brain serotonergic neurons in homeostasis, we used a neuronal silencing tool, mouse RC::FPDi (based on the synthetic G protein-coupled receptor Di), designed for cell type-specific, ligand-inducible, and reversible suppression of action potential firing. In mice harboring Di-expressing serotonergic neurons, administration of the ligand clozapine-N-oxide (CNO) by systemic injection attenuated the chemoreflex that normally increases respiration in response to tissue carbon dioxide (CO(2)) elevation and acidosis. At the cellular level, CNO suppressed firing rate increases evoked by CO(2) acidosis. Body thermoregulation at room temperature was also disrupted after CNO triggering of Di; core temperatures plummeted, then recovered. This work establishes that serotonergic neurons regulate life-sustaining respiratory and thermoregulatory networks, and demonstrates a noninvasive tool for mapping neuron function.     

Serum parathyroid hormone in X-linked hypophosphatemia

Serum immunoreactive parathyroid hormone(IPTH) is normal in patients with X-linked hypophosphatemic rickets who are not treated with phosphate salts. Phosphate raises IPTH in these patients. Endogenous IPTH does not influence the existing defect in tubular reabsorption of phosphate in male patients.     

AGTR2 mutations in X-linked mental retardation

Two angiotensin II (Ang II)-specific receptors, AGTR1 and AGTR2, are expressed in the mammalian brain. Ang II actions on blood pressure regulation, water electrolyte balance, and hormone secretion are primarily mediated by AGTR1. The function of AGTR2 remains unclear. Here, we show that expression of the AGTR2 gene was absent in a female patient with mental retardation (MR) who had a balanced X;7 chromosomal translocation. Additionally, 8 of 590 unrelated male patients with MR were found to have sequence changes in the AGTR2 gene, including one frameshift and three missense mutations. These findings indicate a role for AGTR2 in brain development and cognitive function.     

Peroxisomal defects in neonatal-onset and X-linked adrenoleukodystrophies

Accumulation of very long chain fatty acids in X-linked and neonatal forms of adrenoleukodystrophy (ALD) appears to be a consequence of deficient peroxisomal oxidation of very long chain fatty acids. Peroxisomes were readily identified in liver biopsies taken from a patient having the X-linked disorder. However, in liver biopsies from a patient having neonatal-onset ALD, hepatocellular peroxisomes were greatly reduced in size and number, and sedimentable catalase was markedly diminished. The presence of increased concentrations of serum pipecolic acid and the bile acid intermediate, trihydroxycoprostanic acid, in the neonatal ALD patient are associated with a generalized diminution of peroxisomal activities that was not observed in the patient with X-linked ALD.     

文化“杂合”现象与翻译策略

翻译是一种跨文化的交流活动,不同语言间的差异不仅表现在语音、词汇和句法上,更表现在其文化特色上。翻译中,常常会出现两种语言文化的“杂合”现象。把握杂合度,采取恰当的翻译策略,有助于改变文化“杂合”中的失衡现象。     

Comment on "Impaired respiratory and body temperature control upon acute serotonergic neuron inhibition"

Ray et al. (Reports, 29 July 2011, p. 637) assume that clozapine-N4-oxide (CNO) represents a "biologically inert synthetic ligand" that selectively activates the M4 muscarinic receptor-based DREADD (designer receptor exclusively activated by a designer drug). In contrast, due to the redox cycling of CNO with clozapine and to their cell membrane permeability, CNO is biologically active and its conversion products are capable of undermining DREADD effects.     

Dyskeratosis congenita and cancer in mice deficient in ribosomal RNA modification

Mutations in DKC1 cause dyskeratosis congenita (DC), a disease characterized by premature aging and increased tumor susceptibility. The DKC1 protein binds to the box H + ACA small nucleolar RNAs and the RNA component of telomerase. Here we show that hypomorphic Dkc1 mutant (Dkc1m) mice recapitulate in the first and second generations (G1 and G2) the clinical features of DC. Dkc1m cells from G1 and G2 mice were impaired in ribosomal RNA pseudouridylation before the onset of disease. Reductions of telomere length in Dkc1m mice became evident only in later generations. These results suggest that deregulated ribosome function is important in the initiation of DC, whereas telomere shortening may modify and/or exacerbate DC.     

语境在翻译中的作用

语用学从根本上讲是对语言在一定语境中所体现出来的具体意义的科学。本文就翻译的本质和语境的关系及如何在翻译中结合语境避免误译、死译,从而达到有效交际的目的予以分析。     

翻译的政治视角下的鲁迅及其翻译活动

传统研究一直将鲁迅先生的译作简单地定义为开启民智、惊醒国人。本文从翻译的政治这一全新视角入手,分析鲁迅一生的翻译活动,考察其不同阶段选择外国文学作品的异同及其根由。     

X-linked 6-phosphogluconate dehydrogenase in drosophila: subunit associations

6-Phosphogluconate dehydrogenase (PGD) subunits have been dissociated and reassociated in vitro. The intermediate PGD of the heterozygous phenotype is reproduced by reassociation in vitro of subunits derived from the two types of PGD from homozygous flies. This result has a bearingon gene action in the diploid organism and on the mechanism of dosage compensation in Drosophila melanogaster.     

跨文化翻译中的归化和异化

长期以来, 翻译理论中就有直译和意译两种翻译策略之争.而当翻译活动上升到文学、诗歌和政治层面, 直译和意译之争则演变为归化和异化之争.这场论战一直没有形成压倒统一的观点.     

翻译教学中的情感教学

传统的翻译教学重知轻情,侧重翻译技巧的训练和翻译理论的传授而忽略了教师和学生的情感,因此翻译教学中实施情感教学十分必要。教师对翻译教学应保持饱满的教学热情,适当挖掘教材情感,充分激发学生对翻译的浓厚兴趣,引导学生客观认识翻译活动,保持乐观的学习态度,增加学好翻译的信心。     

河南省公共图书馆视障服务问题研究

大力发展图书馆等公益性文化事业,是实现文化强省目标的重要支撑.文章分析河南省公共图书馆视障服务存在的主要问题.指出提升河南省公共图书馆视障服务水平的对策:提供法律和财政支持,引进现代化技术设备,重视宣传,拓展盲人电脑培训的广度和深度,加强盲人文献资源建设,共建、共享盲人文献资源,招募志愿者等.     

关联翻译理论视角下一个热词的翻译思考

以关联翻译理论为指导,以胡锦涛讲话中"不折腾"的译文为例,从"不折腾"的字面含义、时代内涵和深刻寓意出发,以严谨和科学的态度,提出了自己的译法,期望学术界对此类政治性强的翻译进一步商榷和讨论。     

英译汉中的词类转换

文化背景的差异使词类转换在英译汉过程中显得很重要。正确运用词类转换,可使译文通顺流畅,符合汉语表达习惯。     

翻译特性视域下英语文学作品汉译研究

现代化经济的不断发展,以及东西方文化的频繁交流,大量的英语文学作品也被翻译和阅读。本文主要探讨翻译特性视域下英语文学作品汉译,通过对翻译特性、翻译特性下英语文学作品翻译特点研究,给出相应英语文学翻译策略。     

Loss of a parathyroid hormone-sensitive component of phosphate transport in X-linked hypophosphatemia

Mutant hemizygotes with X-linked hypophosphatemia lack a parathyroid hormone-sensitive component of inorganic phosphate transport in kidney; female heterozygotes retain a variable proportion of this type of transport. The residual mechanism for reabsorption in affected males allows inorganic phosphate efflux from the kidney to urine so that net "secretion" is sometimes observed; the latter is directly proportional to the serum concentration of inorganic phosphate. Calcium acts on the kidney tubule to enhance net reabsorption by this component of inorganic phosphate transport.     

汉英文化差异下的颜色词翻译

文化是语言的载体,语言受文化因素的制约。中英文化的差异直接制约着颜色词的翻译,汉译英时可采取直译(意译)加注的方法。