THE +1245G/T POLYMORPHISMS IN THE COLLAGEN TYPE I ALPHA 1 (COL1A1) GENE IN POLISH SKIERS WITH ANTERIOR CRUCIATE LIGAMENT INJURY

Objectives

The aim of this study was to examine the association of +1245G/T polymorphisms in the COL1A1 gene with ACL ruptures in Polish male recreational skiers in a case-control study.

Methods

A total of 138 male recreational skiers with surgically diagnosed primary ACL ruptures, all of whom qualified for ligament reconstruction, were recruited for this study. The control group comprised 183 apparently healthy male skiers with a comparable level of exposure to ACL injury, none of whom had any self-reported history of ligament or tendon injury. DNA samples extracted from the oral epithelial cells were genotyped for the +1245G/T polymorphisms using real-time PCR method.

Results

Genotype distributions among cases and controls conformed to Hardy-Weinberg equilibrium (p = 0.2469 and p = 0.33, respectively). There was a significant difference in the genotype distribution between skiers and controls (p = 0.045, Fisher''s exact test). There was no statistical difference in allele distribution: OR 1.43 (0.91-2.25), p = 0.101 (two-sided Fisher''s exact test).

Conclusions

The risk of ACL ruptures was around 1.43 times lower in carriers of a minor allele G as compared to carriers of the allele T.     

Retrospective assessment of a single fiducial marker tracking regimen with robotic stereotactic body radiation therapy for liver tumours

AimTo investigate tumour motion tracking uncertainties in the CyberKnife Synchrony system with single fiducial marker in liver tumours.BackgroundIn the fiducial-based CyberKnife real-time tumour motion tracking system, multiple fiducial markers are generally used to enable translation and rotation corrections during tracking. However, sometimes a single fiducial marker is employed when rotation corrections are not estimated during treatment.Materials and methodsData were analysed for 32 patients with liver tumours where one fiducial marker was implanted. Four-dimensional computed tomography (CT) scans were performed to determine the internal target volume (ITV). Before the first treatment fraction, the CT scans were repeated and the marker migration was determined. Log files generated by the Synchrony system were obtained after each treatment and the correlation model errors were calculated. Intra-fractional spine rotations were examined on the spine alignment images before and after each treatment.ResultsThe mean (standard deviation) ITV margin was 4.1 (2.3) mm, which correlated weakly with the distance between the fiducial marker and the tumour. The mean migration distance of the marker was 1.5 (0.7) mm. The overall mean correlation model error was 1.03 (0.37) mm in the radial direction. The overall mean spine rotations were 0.27° (0.31), 0.25° (0.22), and 0.23° (0.26) for roll, pitch, and yaw, respectively. The treatment time was moderately associated with the correlation model errors and weakly related to spine rotation in the roll and yaw planes.ConclusionsMore caution and an additional safety margins are required when tracking a single fiducial marker.     

蛤蚧前背侧室嵴(ADVR)的分区及细胞形态学研究

采用解剖学方法和绀织学方法仔细观察,分析蛤蚧（Gekko gecko）前背侧室嵴（ADVR）的形态学分区,发现以ADVR表面的浅沟为标记,参照细胞着色深浅,细胞密度分布特征以及细胞形态大小,可将ADVR分为内侧区（ma）、嘴外侧区（rla）和尾外侧区（cla）等3个部分,为ADVR的结构功能的深入研究提供了形态学依据。     

直接前方入路与后外侧入路全髋关节置换治疗股骨颈骨折的疗效比较及术后髋关节功能的影响因素分析

摘要 目的：比较直接前方入路与后外侧入路全髋关节置换治疗股骨颈骨折的疗效及术后髋关节功能的影响因素分析。方法：选取2019年5月至2021年12月徐州医科大学附属医院收治并行全髋关节置换治疗股骨颈骨折患者96例,按照手术方法的不同分为直接前方入路组（n=48）和后外侧入路组（n=48）。观察两组围术期指标、并发症发生情况,比较两组治疗前后Harris评分、视觉模拟评分法（VAS）。并应用单因素、多因素Logistic回归分析患者术后髋关节功能的影响因素。结果：直接前方入路组下床时间、切口长度、住院时间显著短于后外侧入路组,术中失血量、术后引流量显著低于后外侧入路组,而手术时间显著长于后外侧入路组（P<0.05）。直接前方入路组术后1、3个月Harris评分显著高于后外侧入路组,VAS评分显著低于后外侧入路组（P<0.05）。两组术后并发症发生率比较,无统计学差异（P＞0.05）。两组治疗6个月后髋关节功能优良率比较,差异无统计学意义（P>0.05）。多因素Logistic回归分析结果显示：体质量指数≥24 kg/m²、术后锻炼时间<3 h/d、合并骨质疏松是接受全髋关节置换治疗的股骨颈骨折患者术后髋关节功能不良的危险因素（P＜0.05）。结论：直接前方入路全髋关节置换术较后外侧入路全髋关节置换术短期内优势明显,表现为对患者的创伤更小,术后疼痛程度较轻,有利于患者的髋关节功能恢复。体质量指数≥24 kg/m²、术后锻炼时间<3 h/d、合并骨质疏松是接受全髋关节置换治疗的股骨颈骨折患者术后髋关节功能不良的危险因素。     

家兔胫骨前肌肌纤维型的分布研究

根据家兔胫骨前肌的肌纤维起止、排列和神经支配特征,将该肌分为前、后两个亚体。利用家兔８例１６侧胫骨前肌,按上述两个亚体分别取材,作恒冷箱冰冻横切,肌球蛋白ＡＴＰ酶染色,将肌纤维分为Ⅰ型、ⅡＡ型、ⅡＢ型,检测各亚体的肌纤维型构成比例,肌束内肌纤维的分布特征,并用图象分析仪测量各亚体肌纤维横切面积和直径。结果发现,前、后亚体以Ⅱ型纤维居多,前亚体ⅡＡ型纤维高达３５．４％,后亚体Ⅰ型纤维多达２４．５％,两者的ⅡＢ型纤维均达５０％左右。而左、右侧之间无差异,肌束周边部内Ⅰ型纤维仅占１２．７～１３．３％,ⅡＢ型纤维高达５９．９～６０．０％,说明受肌束膜压迫影响,ⅡＢ型肌纤维血供少,以适应无氧酵解的功能。各亚体的Ⅰ型纤维较细,Ⅱ型纤维较Ⅱ粗,Ａ型与ⅡＢ型二者相似。作者认为,前亚体主要参与快速有力的足背屈运动,后亚体则维持踝关节的稳定,保持足弓的形状和弹性,以便适应该肌的站立、跑动和跳跃的功能。     

THE AUTOFLUORESCENT FLAGELLUM: A NEW PHYLOGENETIC ENIGMA1

Epifluorescence microscopy reveals the presence of fluorescence in the living cells of at least three classes of flagellates. In Ochromonas cells, the fluorescence is blue-green in color and is found only in the short flagellum, both in the flagellar swelling and throughout the length of the flagellum. As recognized by the locale and color of the flagellar fluorescence, the same fluorescence is observed in only certain other heterokont algal groups but is also found in one of the two isokont flagella of the prymnesiophyte Prymnesium parvum.     

Length and overall sequence of the PEN-2 C-terminal domain determines its function in the stabilization of presenilin fragments

Gamma-secretase is an aspartyl protease complex that catalyzes the intramembrane cleavage of a subset of type I transmembrane proteins including the beta-amyloid precursor protein (APP) implicated in Alzheimer's disease. Presenilin (PS), nicastrin (NCT), anterior pharynx defective (APH-1) and presenilin enhancer-2 (PEN-2) constitute the active gamma-secretase complex. PEN-2, the smallest subunit, is required for triggering PS endoproteolysis. Stabilization of the resultant N- and C-terminal fragments, which carry the catalytically active site aspartates, but not endoproteolysis itself, requires the C-terminal domain of PEN-2. To functionally dissect the C-terminal domain we created C-terminal deletion mutants and mutagenized several evolutionary highly conserved residues. The PEN-2 mutants were then probed for functional complementation of a PEN-2 knockdown, which displays deficient PS1 endoproteolysis and impaired NCT maturation. Progressive truncation of the C-terminus caused increasing loss of function. This was also observed for an internal deletion mutant as well as for C-terminally tagged PEN-2 with a twofold elongated C-terminal domain. Interestingly, only simultaneous, but not individual substitution of the highly conserved D90, F94, P97 and G99 residues with alanine interfered with PEN-2 function. All loss of function mutants identified allowed PS1 endoproteolysis, but failed to stably associate with the resultant PS1 fragments, which like the PEN-2 loss of function mutants underwent proteasomal degradation. However, complex formation of the PEN-2 mutants with PS1 fragments could be recovered when proteasomal degradation was blocked. Taken together, our data suggest that the PS-subunit stabilizing function of PEN-2 depends on length and overall sequence of its C-terminal domain.