Differential titin isoform expression in human skeletal muscle

Mammalian skeletal muscle expresses at least two isoforms of the cytoskeletal protein titin (connectin; MW ≈ 3000 kDa). These isoforms are associated with different passive force curves, and thus may affect physical performance. To study the distribution of titin and its possible influence on performance in humans, muscle biopsies were obtained from 15 males (X ± SE; age = 25.4 ± 2.9 years, height = 177.7 ± 1.8 cm, weight = 76.5 ± 2.2 kg). Two biopsies were obtained on separate occasions from both the right and left vastus lateralis, and one biopsy each from the lateral head of the right gastrocnemius and the right soleus, with all biopsies handled identically. Fibre type analyses were performed via mATPase histochemistry. Expression of titin and myosin heavy chain isoforms were determined by SDS-PAGE. Titin bands in the resulting gels were highly repeatable and were verified by migration patterns, as well as Western blot analysis. Two groups of subjects were identified: group 1 (n=10) expressed only one titin isoform (titin-1) in all biopsies, and group 2 (n=5) expressed two titin isoforms (titin-1 and titin-2) in all biopsies. No significant differences (P> 0.05) between groups were observed for percentage fibre types, percentage fibre type areas, fibre type cross-sectional areas, and percentage myosin heavy chain expression when comparing individual muscles, sampling times or bilateral comparisons. This is the first report of differential titin isoform expression in healthy, mature human skeletal muscle, but it is not clear why this occurs or what influence this may have on performance.     

间餐与中学生脑力工作能力关系研究

为阐明课间加餐对中学生上午学习能力的影响，采用剂量作业试验，通过自身前后对比，分析了间餐与脑力工作能力的关系，结果表明间餐不仅加快了脑力工作速度，控制了末节课的错误率，而且较有效地降低了显著疲劳发生率，经ｌｏｇｉｓｔｉｃ逐步回归分析，显示间餐及高质量早餐均为阻遏疲劳发生之保护因子。     

不同状态人体牙槽骨的弹性性质

人体下颌牙槽骨皮质骨是各向异性复合生物材料,组织结构上类似于胶原羟磷灰石纤维增强的单向纤维增强复合材料。本文应用电测法测试了不同状态人体下颌牙槽骨皮质骨在平面应力状态下的各向异性弹性常数。     

Non-nociceptive capsaicin-sensitive nerve terminal stimulation allows for an original vasodilatory reflex in the human skin

A significant increase of cutaneous laser Doppler flowmetry was found before blood flow decreases with increasing pressure during a 5 mmHg min⁻¹ increase of pressure strain on the finger. Pre-treatment with a local anaesthetic or chronically applied capsaicin, resulted in the disappearance of the vasodilatory response. These results suggest an original vasodilatory axon reflex response to non-noxious pressure strain which is initiated by capsaicin-sensitive nerve terminals in the human skin.     

应用型本科院校护理学毕业生科研能力及影响因素分析

目的 了解应用型本科院校护理学毕业生科研能力及其影响因素。方法 采用整群抽样方法,抽取湖南省某地方应用型本科院校护理学专业272名应届毕业生作为研究对象。采用护理人员科研能力自评量表、评判性思维能力量表进行问卷调查。采用SPSS 22.0进行独立样本t检验、方差分析、Spearman相关分析及多元线性回归。结果 应用型本科院校护理学毕业生的科研能力得分为（49.27±21.26）分,255名（93.7%）毕业生处于中等及以下水平。科研能力与评判性思维能力总分、分析能力、评判思维的自信心及求知欲呈正相关（r=0.18、0.23、0.45、0.32,均P<0.01）,与寻找真相呈负相关（r=-0.16,P<0.05）。线性回归分析可见培养方式、科研实践经历、科研动机、评判思维的自信心、寻找真相为护理学毕业生科研能力的影响因素（标准化β=0.12、0.16、0.14、1.31、-0.12,均P<0.05）。结论 应用型本科院校护理学毕业生的科研能力,尤其是资料处理能力及研究设计能力有待提高。可通过树立正确的科研动机、加强在校期间评判性思维能力培训、鼓励科研实践等途径进行针对性培养。     

电阻应变式传感器在下肢牵引手术中的应用

目的 研究电阻应变式传感器（RSS）在不同下肢骨折类型手术中的应用。方法 选择2020年10月—2022年8月中国科学技术大学附属第一医院收治的外伤性下肢骨折患者99例,按照骨折类型分为股骨粗隆间骨折组79例、股骨干骨折组15例、股骨颈骨折组5例。患者均在牵引床上行闭合复位内固定术,使用RSS测量3组不同骨折类型手术中的初始牵引力、牵引时长、松解牵引力。记录手术时间、术中出血量,术后评分及3组不同骨折类型手术前后血色素变化及输血情况;比较使用不同内固定方式（长髓内钉、短髓内钉、空心钉）的术中牵引力和手术出血量、手术时间;比较长髓内钉固定患者和短髓内钉固定患者时下肢旋转角度。结果 3组不同骨折类型初始牵引力、牵引时长、松解牵引力、手术时长、术中出血量、术后评分比较,差异均有统计学意义（P <0.05）。3组不同骨折类型术前、术后血红蛋白、红细胞压积比较,差异均有统计学意义（P <0.05）。3组术中输血情况比较,差异有统计学意义（P <0.05）,术后输血情况比较,差异无统计学意义（P>0.05）。使用不同内固定方式的患者牵引总时长、年龄、术中出血量、手术时间比较...     

Restriction endonuclease analysis of varicella-zoster vaccine virus and wild-type DNAs

The DNA from several clinical isolates of varicella-zoster virus (VZV) were compared with the DNA from the vaccine strain VZV using three restriction endonucleases: BamHI, BgII, and HpaI. When electrophoresed through an agarose gel, the vaccine DNA digestion pattern was significantly different from the digestion patterns of the wild-type DNAs. Variations in the digestion pattern of the separate clinical isolates were also observed.     

Complete Nucleotide Sequence of the Rice Tungro Spherical Virus Genome of the Highly Virulent Strain Vt6

The complete nucleotide sequence of rice tungro spherical virus (RTSV) strain Vt6, originally from Mindanao, the Philippines, with higher virulence to resistant rice cultivars, was determined and compared with the published sequence for the Philippine-type strain A (RTSV-A-Shen). It was reported that RTSV-A was not able to infect a rice resistant cultivar TKM 6 (10). RTSV-Vt6 and RTSV-A-Shen share 90% and 95% homology at nucleotide and amino-acid levels, respectively. The N-terminal leader sequence of RTSV-Vt6 contained a 39-amino acids-region (positions 65 to 103) which was totally different from that of RTSV-A-Shen; the difference resulted from frame shifting by nucleotide insertions and deletions. To confirm the amino-acid sequence differences of the leader polypeptide, the same region was cloned and sequenced using a newly obtained variant of RTSV-type 6, which had been collected in the field of IRRI, and seven field isolates from Mindanao, the Philippines. Since all the sequences of the target region are identical to that of the Vt6 leader polypeptide, the sequence difference in the leader region seems not to correlate with the virulence of Vt6.