两种MRI序列对听神经瘤成象的比较与评价

为选择中等场强的ＭＲＩ听神经瘤成像最佳序列。收集手术和病理证实的听神经瘤１３５例，分析序列Ⅰ、Ⅱ对内听道中心层面、三叉神经显示率及ＭＲ征象的显示情况。结果：序列Ｉ择内听道中心层面及三叉神经的显示均优于序列Ⅱ，序列Ⅱ在显示肿瘤内囊变、出血、不肿优于序列Ｉ；对肿瘤钙化、肿瘤血管、脑干移位的观察，两者相仿。结果显示：序列Ｉ在中等场经下作为听神经瘤成像的首选序列，并中运用到小脑角区ＭＲＩ成像。     

Genome of the European elk papillomavirus (EEPV)

The genome of the European elk papillomavirus (EEPV) was found to be 8,095 base pairs (bp) long and its genetic organization was similar to that of other papillomaviruses. Ten open reading frames (ORFs), designated E1-E7 and L1-L3, were identified in the genome, all located on one strand. The presence of the L3 ORF is rare among the papillomaviruses and to date has only been identified in the genomes of EEPV, the deer papillomavirus (DPV) and the Cottontail papillomavirus (CRPV). The ORF is well conserved beteeen DPV and EEPV with regard to both length and sequence. Potential promoter regions were identified at the 5-end of the E6 ORF, at the 3-end of the E1 ORF and downstream of the L1 ORF. Furthermore, two potential polyadenylation signals were found, one located in the long control region (LCR), downstream of the L1 ORF, and another preceding the L2 ORF. The EEVP genome is closely related to the genome of the DPV, the most highly conserved regions being ORFs E1 (70%), E5 (69%), and L1 (74%).     

PCR ANALYSIS OF Y-CHROMOSOME SEQUENCES IN A 45,X MALE PATIENT AND A REVIEW OF THE LITERATURE

The 45,X karyotype is usually associated with Turner syndrome, while male phenotype is exceptional. The authors report a 45,X male patient with normal external genitalia and sex behavior, but who was azoospermic. He had a normally developed musculature and pilose distribution, testicular volume of 15 mL and no gynecomastia but clinical stigmata of Turner syndrome (short stature, short neck and 4th metacarpal bones) and azoospermia. Hormonal plasma levels of testosterone, estradiol, prolactin, and gonadotrophins were within the normal range as was the response of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) (30 and 60 min) after 100 mug iv of LH-RH administration. Testicular biopsy could not be performed. Karyotype was 45,X without evidence of mosaicism. Polymerase chain reaction of genomic DNA studied with 12 different sequences of Y chromosome revealed only the presence of SRY gene (testis determining factor). It is possible that SRY/autosomal translocation had occurred in this patient. The study of 45,X male should be of great value in elucidating the complex mechanisms involved in normal male sex differentiation.     

Analysis of the genetic and the corresponding antigenic variability of the VP1 3′ end of ECHO virus type 11 and ECHO virus type 30

The enteroviruses (EV), RNA viruses belonging to the Picornaviridae family, have a high genetic variability due to the absence of the efficient proofreading and post replicative repair activities associated with the RNA polymerase. In the present work, we studied the genetic and the antigenic variability of ECHO virus types 11 (E11) and 30 (E30), which are the most isolated echoviruses serotypes in clinical and environmental samples. We established on the 3′ end of the VP1 gene, consensus sequences of E11 and E30 by alignment of 67 E11 and 247 E30 published sequences in GenBank. Our results of sequences comparison showed that the majority of the mutational sites are situated on the third nucleotide of the codon. These mutations were without consequence on the antigenic sequences of the VP1 protein. Thus, E11 and E30 have a high genetic variability (1/3 of the nucleotides are variable), but a relative antigenic conservation. The analysis of the intertypic antigenic variability between E11 and E30 was obtained by the alignment of the corresponding amino acids sequences relative to the N-terminal part of the VP1 protein. Two discriminating parts were highlighted, probably representing antigenic sites for neutralisation antibodies.     

Development of an improved genotyping assay for the detection of hepatitis C virus genotypes and subtypes in Pakistan

A new genotyping system was established for the specific detection of HCV genotypes 1a, 1b, 1c, 2a, 2b, 2c, 3a, 3b, 3c, 4a–h, 5a and 6a during the course of this study. The system is based on entire core region and a part of 5′ noncoding region (5′NCR) with genotype-specific primers. Genotype-specific primers were designed on the basis of 114 HCV isolates. Serum samples with known genotypes were used as positive controls to validate the assay developed and to generate PCR band patterns. Band patterns generated from the clinical serum samples from HCV patients were compared to the patterns produced from these control samples. In addition, the type-specific bands were sequenced from the test patients and control clinical samples to validate further the test results. To determine sensitivity and specificity of the assay, a total 260 samples were analyzed simultaneously by this HCV genotyping method and that developed by Ohno and Murex HCV Serotyping 1–6 Assay. The system showed 79.2% concordance with Ohno's system and 65.38% with serotyping system. Samples with discordant results were sequenced and their genotypes were determined by molecular evolutionary analysis. The data indicate that the method described in this study may offer better sensitivity and specificity for the detection directly of HCV genotypes present at low levels in HCV patient samples.     

MRI多序列对宫颈癌的临床应用价值分析

目的探索MRI多序列对宫颈癌的诊断应用分析及临床意义。方法回顾性分析我院2013年1月至2015年12月入院行MRI检查并经病理证实的宫颈癌病人90例的影像学图像,通过患者典型的MRI影像学表现,结合病理学资料,分别从MRI平扫、DWI以及增强扫描分析对宫颈癌诊断的应用和意义。结果 MRI平扫能够在任意方向直接成像更好的体现了肿瘤大小以及与周围组织的相互关系,DWI图像上可以清楚的突出肿瘤病灶,更有利于病灶的检出;MRI增强扫描可提高分期准确性,判断其侵犯方位,为临床治疗提供影像学资料。结论 MRI具有高分辨率的优势,能从多轴位清晰显示宫颈癌大小及侵犯范围,为临床治疗提供影像资料,MRI可用于宫颈癌常规的首选检查方法。     

Emotion stimulus processing in narcolepsy with cataplexy

Reported brain abnormalities in anatomy and function in patients with narcolepsy with cataplexy led to a project based on qualitative electroencephalography examination and analysis in an attempt to find a narcolepsy with cataplexy‐specific brain‐derived pattern, or a sequence of brain locations involved in processing humorous stimuli. Laughter is the trigger of cataplexy in these patients, and the difference between patients and healthy controls during the laughter should therefore be notable. Twenty‐six adult patients (14 male, 12 female) suffering from narcolepsy with cataplexy and 10 healthy controls (five male, five female) were examined. The experiment was performed using a 256‐channel electroencephalogram and then processed using specialized software built according to the scientific research team's specifications. The software utilizes electroencephalographic data recorded during elevated emotional states in participants to calculate the sequence of brain areas involved in emotion processing using non‐linear and linear algorithms. Results show significant differences in activation (pre‐laughter) patterns between the patients with narcolepsy and healthy controls, as well as significant similarities within the patients and the controls. Specifically, gyrus orbitalis, rectus and occipitalis inferior are active in healthy controls, while gyrus paracentralis, cingularis and cuneus are activated solely in the patients in response to humorous audio stimulus. There are qualitative electroencephalographic‐based patterns clearly discriminating between patients with narcolepsy and healthy controls during laughter processing.     

Control of remembered reaching sequences in monkey

Single-neuron responses in motor and premotor cortex were recorded during a movement-sequence delay task. On each trial the monkey viewed a randomly selected sequence of target lights arrayed in two-dimensional space, remembered the sequence during a delay period, and then generated a coordinated sequence of movements to the remembered targets. Of 307 neurons studied, 25% were tuned specifically for either the first or the second target, but not both. In particular, for neurons tuned during both target presentations, tuned activity related to a particular first target direction were maintained during the presentation of a second target in a different direction. During the delay period, 32% of the neurons were tuned for upcoming movement in a single direction. These delay period responses often reflected activity patterns that first developed during target presentations and may therefore act to maintain target period information during the delay. Neurons with tuned activity during both the delay and movement periods exhibited two patterns: the first exhibited tuned responses during the delay that were correlated with the tuning of first-movement responses, while the second pattern showed delay-period tuning that was better correlated with tuned responses during second movements. This indicates that, before movement, distinct neural populations are correlated with specific movements in a sequence. About half the neurons studied were not directionally tuned during the initiation, target, or delay periods, but did show systematic changes in activity during task performance. Some (34%) were exclusively tuned during movement and appear to be involved in the direct control of movement. Others (17%) showed changes in firing rate from period to period within a trial but showed no directional preference for a particular direction of movement. Population analyses of tuned activity during the target and delay periods indicated that accurate directional information about both first and second movements was available in the neuronal ensemble well before reaching began. These results extend the idea that both motor and premotor cortex play a role in reaching behavior other than the direct control of muscles. While some early neural responses resembled muscle activation patterns involved in maintaining fixed postures before movement, others probably relate to the sensory-to-motor transformations, information storage in short-term memory, and movement preparation required to generate accurate reaching to remembered locations in space.