三烯霉素J——来自深海细菌Ochrobactrum sp.的新安莎霉素

目的探究深海来源细菌Ochrobactrum sp. OUCMDZ-2164中的细胞毒活性代谢产物。方法利用硅胶柱色谱、凝胶柱色谱和高效液相色谱等手段对发酵产物进行分离纯化,运用紫外、红外、质谱、核磁共振及圆二色谱等方法鉴定化合物的结构,采用MTT和细胞计数试剂盒-8(CCK-8)法分别评价化合物对乳腺癌MCF-7细胞和肺癌A549细胞及慢性髓性白血病K562细胞的增殖抑制活性。结果从细菌Ochrobactrum sp. OUCMDZ-2164的发酵产物中分离获得了4个化合物,分别鉴定为3-O-去甲基三烯霉醇(1)、flazin(2)、flazin-3-carboxylicacid(3)和胸腺嘧啶(4)。化合物1在10μmol/L浓度下对MCF-7细胞的增殖抑制率为61.5%。结论化合物1为新的安沙霉素类化合物,命名为三烯霉素J,其具有一定的乳腺癌细胞毒活性。     

慢性粒细胞白血病端粒酶的相关研究

目的：对慢性粒细胞白血病端粒酶进行研究,采用 PCR －ELISA 半定量法测定端粒酶活性,同时观察端粒酶活性变化的相关性。方法：选取15例慢性粒细胞白血病患者骨髓标本和15例正常骨髓（取自非肿瘤病人需行骨髓检查者）样本分为慢性粒细胞白血病组（CML 组）和正常对照组,采用 PCR －ELISA 法来测定CML 组和正常对照组的端粒酶活性。结果：正常对照组端粒酶具有微弱的活性,而 CML 组则具有较强的活性,且端粒酶活性 CML 组高于正常对照组,两者差异性非常显著。其中,CML 组男性与女性组间端粒酶活性差异无统计学意义。结论：正常组端粒酶具有微弱的活性,而 CML 组则具有较强的活性。端粒酶活性可能反映了一个高度增生的状态,是一种新的肿瘤标记物,与肿瘤发生密切相关。     

体内成熟与体外成熟的卵母细胞纺锤体位置及其与胚胎发育的关系

目的研究体内成熟与体外成熟卵母细胞的纺锤体位置及其与胚胎发育的关系。方法对134个体内成熟卵母细胞在卵母细胞胞质内单精子注射法（ICSI）操作时用纺锤体实时观察仪进行纺锤体位置的观察,体内成熟卵母细胞来自单纯因男性不育而进行ICSI治疗的患者15例（体内成熟组）。另外对45个体外成熟的卵母细胞观察纺锤体位置,体外成熟卵母细胞来自因多囊卵巢综合征致不孕而进行治疗的患者5例（体外成熟组）。纺锤体的位置按照其与第一极体之间的角度不同分为Ⅰ、Ⅱ、Ⅲ、Ⅳ和Ⅴ级。并观察两组成熟卵母细胞的受精及其胚胎发育情况。结果体内成熟组和体外成熟组患者的卵母细胞中可观察到纺锤体的分别占83．6％（112／134）和82．2％（37／45）。体内成熟组患者卵母细胞纺锤体的位置Ⅰ、Ⅱ、Ⅲ、Ⅳ和Ⅴ级分别为22．4％、55．2％、3．O％、3．O％、16．4％,体外成熟组则分别为17．8％、51．1％、8．9％、4．4％、17．8％,两组各级间分别比较,差异均无统计学意义（P〉0．05）。在体内成熟组卵母细胞中,纺锤体离第一极体较近（Ⅰ级）者受精率较高（93．3％）,显著高于其他各级（分别为73．0％、2／4、1／4、63．6％,P〈0．05）。结论体内成熟与体外成熟卵母细胞间纺锤体位置未见显著差异;纺锤体的位置与卵母细胞受精率有一定相关性。     

不同区域土壤中锰 铅和铬的化学形态分析研究

研究同一城市不同区域土壤中锰、铅和铬的化学形态分布情况。用BCR连续提取法提取土壤中锰、铅和铬的不同化学形态,用原子吸收光谱法测定各元素的总量及相关形态的含量。不同区域土壤中3种重金属总量的分布规律一致,大小依次为Mn>Pb>Cr。3种金属元素的形态分布有其各自规律,但均以不活泼的残渣态为主。     

初诊断早发2型糖尿病患者胰岛素抵抗及胰岛β细胞功能分析

目的 分析初诊断早发2型糖尿病患者的临床特点,探讨胰岛素抵抗及胰岛素分泌缺陷对早发2型糖尿病的影响。方法 收集2019年1月至2021年2月在该院内分泌科住院的215例初诊断早发2型糖尿病患者作为研究组,同时收集同期经口服葡萄糖耐量试验筛查排除糖尿病者55例为对照组,收集一般资料及胰岛素、血脂水平等资料进行分析。结果 研究组男性构成比、BMI、甘油三酯、总胆固醇、低密度脂蛋白、Ln[胰岛素抵抗指数(HOMA-IR)]水平高于对照组,高密度脂蛋白、Ln[胰岛素分泌指数(HOMA-β)]低于对照组,差异有统计学意义(P<0.05)。将HOMA-IR及HOMA-β标准化为Z值后进行logistic回归分析,显示HOMA-IR及HOMA-β均是早发2型糖尿病的独立影响因素,且二者存在交互作用(P<0.05)。HOMA-IR取对数进行多元线性回归分析,提示BMI是HOMA-IR的影响因素,方程为Ln(HOMA-IR)=0.325×BMI(R²=0.343,P<0.05)。结论 相较于胰岛素分泌缺陷,胰岛素抵抗对早发2型糖尿病的患病影响可能更大,超重和肥胖是...     

Simultaneous quantification of apolipoproteins A-I,E, and J in human plasma by LC-MS/MS for clinical application to diabetes mellitus complicated with cardiovascular disease

Apolipoproteins (Apos) play an important role in regulating plasma lipid concentration. Complex disorders of Apos are highly related with diabetes mellitus, cardiovascular and other diseases. Direct measures of lipoprotein fractions for risk assessment suffer from inaccuracy in the dyslipidemia and pathological states. Therefore, a reliable precise assay will be of high clinical utility. LC-MS/MS methods with multiple reaction monitoring modes have proven suitable for multiplexed quantification. We aimed to develop a simple, cost-effective and amenable LC-MS/MS assay for quantification of ApoA-I, ApoE and ApoJ in human plasma. Standards were constructed from substitute matrix and proteotypic peptides for external calibration and corresponding stable isotope labeled peptides were added as internal standards to remove matrix effects. Analytical validation of the assay included the assessment of linearity, accuracy (RE: −3.02% to 5.32%), intra-assay precision (RSD: 2.50% to 6.56%), inter-assay precision (RSD: 0.78% to 6.68%), spiking recovery rate (accuracy: 87.17% to 112.71%), matrix effect (accuracy: 88.03% to 114.87%), and reproducibility and repeatability of sample preparation (RSD: 1.95% to 7.26%). The performance of proteotypic peptides ApoA-I, ApoE and ApoJ was sufficient for triplex quantitation within a linear range from 16.26 to 1626.41 pmol mL⁻¹, 1.03 to 103.35 pmol mL⁻¹ and 0.86 to 86.46 pmol mL⁻¹ respectively. For all quantified peptides, the determination coefficient (R²) was >0.997. Besides, the validated LC-MS/MS method has been successfully applied to the quantification of plasma samples in diabetes mellitus and cardiovascular diseases. We anticipate that this assay may provide an alternative method for future clinical applications.

Simultaneous quantification of apolipoproteins A-I, E, and J in human plasma by LC-MS/MS.     

Arthroscopic Modified Double‐Row Biceps Tenodesis versus Labral Repair for the Treatment of Isolated Type II SLAP Lesions in Non‐Overhead Athletes

ObjectiveTo evaluate the postoperative efficacy and the clinical outcomes of arthroscopic modified double‐row biceps tenodesis versus labral repair.MethodsA retrospective study was conducted in 56 patients with isolated type II superior labrum anterior and posterior (SLAP) lesions from March 2015 to November 2018. Thirty patients (male:female = 17:13) were treated with labral repair, and 26 patients (male:female = 15:11) were treated with modified double‐row biceps tenodesis. The average age of the labral repair group and the modified double‐row biceps tenodesis group were 42.8 ± 10.6 and 40.9 ± 10.2 years, respectively. Pre‐ and postoperative assessments with the visual analog scale (VAS), University of California Los Angeles (UCLA), and American Shoulder and Elbow Surgeons (ASES) scores were compared between the two treatment groups. Additional outcome measures included patient satisfaction, the time to return to previous activities, workers'' compensation status, and postoperative complications.ResultsAt a 2‐year follow‐up, the tenodesis group showed significant differences in postoperative VAS (1.5 to 1.8, respectively; p = 0.008), patient satisfaction (92.3% vs. 46.7%, p < 0.001), and recovery time to return to their previous activities (6.8 ± 1.8 vs. 8.1 ± 1.5, p = 0.007) compared to the labral repair group; however, there was no significant difference in postoperative ASES and UCLA scores between the two groups. Additionally, one patient in the tenodesis group developed persistent postoperative stiffness, which was resolved by conservative treatment. In the labral repair group, two patients presented with persistent postoperative night pain, three developed persistent postoperative stiffness, and two required a subsequent capsular release.ConclusionsCompared with the labral repair group, the arthroscopic modified double‐row biceps tenodesis showed more encouraging postoperative pain reduction, earlier recovery to previous activities, and higher patient satisfaction.     

Study on the Initiation of Interface Crack in Rock Joints

The interfacial fracture of rock joints is an important although easily ignored issue in jointed rock engineering. To conduct this study, an interface crack model of rock joints was proposed. By analyzing the ratio of stress intensity factor to fracture toughness, the fracture mode of the interface crack was studied. Based on the Mohr-Coulomb criterion, an interface fracture criterion considering T-stress was established. To verify the proposed fracture criterion, laboratory and numerical tests were conducted. Finally, the effect of relative critical size α, internal friction angle φ and cohesion c on the initiation of an interface crack was comprehensively discussed. It is concluded that the proposed fracture criterion can predit the initiation of the interface cracks properly. With an increase in cohesion c, mode II fracture toughness K_IIC also clearly increases. When the absolute value of K_I is small, the effect of α is much larger than that of φ. In addition, with an increase in the absolute value of the mode I stress intensity factor, the φ of the joint plays a more important role in the initiation of the interface crack.     

异基因造血干细胞移植后中枢神经系统并发症的危险因素及生存分析

目的： 探讨异基因造血干细胞移植(hematopoietic stem cell transplantation,HSCT)后中枢神经系统 (central nervous system,CNS)并发症的危险因素以及对患者生存的影响。方法： 采用回顾性分析的方法,收集中南 大学湘雅医院血液科2016 年9 月至2019 年9 月行异基因HSCT的323 例患者的临床资料,对发生CNS并发症的患者 并发症发生的时间、常见的症状等临床资料进行统计学描述。采用单因素及多因素分析方法分析异基因HSCT 后 CNS并发症发生的危险因素,并进行生存分析。结果： 在323 例行异基因HSCT的患者中,发生CNS并发症的有32 例,发生CNS 并发症的中位时间为移植后32( −1~584) d,常见的症状为意识障碍(78.1%)、抽搐(59.4%)、头痛 (12.5%)。单因素分析结果显示： 中性粒细胞植活情况、血小板(platelet,PLT) 植活情况、血清巨细胞病毒 (cytomegalovirus,CMV)DNA阳性、合并急性移植物抗宿主病(acute graft versus host disease,aGVHD)、供者选择是影响 异基因HSCT后CNS并发症发生的相关临床因素(分别P=0.011,P<0.001,P=0.006,P<0.001,P=0.035)。多因素分析 结果显示：PLT 植活延迟或未植活、合并aGVHD为CNS并发症发生的危险因素(均P<0.001)。生存分析结果显示： 发生CNS并发症的患者1 年总生存率(overall survival rate,OS)和2 年OS均明显低于未发生的患者(55%±9% vs 89%± 2%,37%±11% vs 85%±3%;均P<0.001);发生CNS并发症的患者1 年无病生存率(disease free survival rate,DFS)和2 年DFS均明显低于未发生患者(55%±9% vs 88%±2%,29%±11% vs 83%±3%;均P<0.001);发生CNS并发症的患者1 年移植相关病死率(transplantation-related mortality,TRM)和2 年TRM 均明显高于未发生患者(45%±9% vs 8%±2%, 58%±11% vs 11%±2%;均P<0.001)。结论： PLT植活延迟或未植活、合并aGVHD为异基因HSCT后CNS并发症发生 的危险因素,提示当异基因HSCT患者PLT植活延迟或未植活,或是合并aGVHD时,需警惕CNS并发症的发生。与 未发生CNS并发症的患者相比,发生该并发症的患者往往预后不良。