某高校护理和预防两个专业大学生核黄素营养状况分析

目的了解大学生核黄素营养状况，并探讨其影响因素。方法对护理、预防专业的学生进行核黄素4h负荷尿试验，用荧光光度法测定核黄素含量。结果护理学专业的学生核黄素不足的占78．79％，正常占10．10％，充裕的占11.31％。预防医学专业的学生核黄素不足的占74．42％，正常的占16．28％，充裕的占9．3％。专业之间差异无显著性意义（P〉0．05）。结论大学生的核黄素营养水平普遍较低，其中动物性食品摄人较少、学生对合理膳食的营养知识缺乏是核黄素摄人不足的主要原因。     

Hemolytic properties and riboflavin synthesis of Helicobacter pylori: cloning and functional characterization of the ribA gene encoding GTP-cyclohydrolase II that confers hemolytic activity to Escherichia coli

Various strains of Helicobacter pylori were able to lyse erythrocytes from sheep, horse, and human when grown on blood agar. The hemolysis did not depend on the production of the vacuolating cytotoxin VacA as demonstrated by the hemolytic behavior of an isogenic vacA-negative mutant strain. The hemolytic activity could be detected in cell-free supernatants and was not regulated by iron. To isolate genes coding for proteins involved in the destruction of erythrocytes, a plasmid-based DNA library was screened for expression of lytic activity on blood agar. This approach revealed that the H. pylori ribA gene confers hemolytic properties to Escherichia coli. The ribA gene encodes the enzyme GTP-cyclohydrolase II [EC 3.5.4.25] that catalyzes the initial step in the synthesis of riboflavin. The predicted amino acid sequence of the H. pylori RibA protein showed a high degree of similarity to equivalent enzymes from microorganisms and from plants. The single gene on a plasmid restored riboflavin synthesis in a ribA mutant of E. coli and induced hemolytic activity. Furthermore, ribA overexpression was associated with the production of a fluorescent yellow molecule that was not identical with riboflavin. Hemolysis was also seen for the ribA gene from E. coli, indicating that this feature was not specific for the H. pylori gene. The presence of ribA in various H. pylori strains was confirmed by Southern blot hybridization and by polymerase chain reaction with specific primers. This analysis revealed that microdiversity exists within the DNA region upstream from ribA, which was further confirmed by nucleotide sequence analysis. Received: 25 July 1997     

脂质沉积性肌病42例临床治疗和预后随访

目的探讨脂质沉积性肌病（LSM）的临床特点、药物治疗效果和预后情况。方法回顾性分析42例LSM患者临床资料并对其治疗效果和预后情况进行随访。结果全部患者均有治疗期间的短期随访资料，其中小剂量泼尼松治疗33例，单用核黄素（维生素B2）治疗9例，全部患者1个月内肌无力症状均获明显改善。随访1年以上者共32例，其中26例肌力完全恢复正常，另6例仍不能耐受重体力劳动，运动耐力较健康人差。13例患者症状有不同程度复发，其中7例有家族史，复发的13例中有12例是在冬季复发，均以劳累、感冒为诱因，5例患者复发2次以上。结论LSM是可治疗的肌肉疾病，对小剂量泼尼松治疗有效，部分患者有复发倾向，有家族史患者更容易复发。单用核黄素治疗反应良好的LSM可能为戊二酸尿症Ⅱ型所致，提示应根据LSM的不同病因采取不同的治疗方案。     

光照疗法对新生儿红细胞谷胱甘肽还原酶活性的影响

作者对光照疗法（光疗）前及光疗后于口服维生素Ｂ＿２（４３例）和不予口服维生素Ｂ＿２（１７例）的黄疸新生儿的红细胞谷胱甘肽还原酶（ＧＲ）的活性进行了动态观察。结果显示，接受短期光疗的黄疸新生儿其红细胞ＧＲ活性较光疗前的ＧＲ活性有显著下降，光疗后予口服维生素Ｂ＿２可使下降的红细胞ＧＲ活性回升，而不予补充维生素Ｂ＿２者的红细胞ＧＲ活性继续下降。光疗的时间越长，红细胞ＧＲ活性的下降越明显，补充维生素Ｂ＿２使红细胞ＧＲ活性回复到正常水平所需的时间也越长。短期光疗也可引起体内维生素Ｂ＿２的降解，导致红细胞ＧＲ活性的下降，为避免因红细胞ＧＲ活性下降引起的红细胞额外破坏，对接受光疗的黄疸新生儿常规补充维生素Ｂ＿２的是必要的。     

核黄素防治放射性口腔黏膜炎的疗效观察

目的观察核黄素磷酸钠联合康复新液用于鼻咽癌放射性口腔黏膜炎的预防及治疗效果。方法选取我院经病理确诊的74例初诊放疗的鼻咽癌患者,随机分为试验组及对照组。试验组37例:核黄素磷酸钠联合康复新液。具体用药:核黄素磷酸钠注射液30 mg+生理盐水100 m L,放疗期间1次/d静点;康复新液,放疗期间3次/d,10 m L/次,于口中含服3~5 min后缓慢咽下。对照组:康复新液单药,用药剂量及用法与试验组相同。结果 74例均纳入分析,试验组患者Ⅱ级以上放射性口腔黏膜炎的发生率明显低于对照组(37.8%vs.67.6%,P=0.019);试验组患者主要为轻度疼痛(67.6%),而对照组以中度疼痛为主(56.8%),两组疼痛程度比较,差异有统计学意义(P=0.035)。本研究中未观察到重度药物相关不良反应,提示药物安全性良好。结论核黄素磷酸钠联合康复新液防治放射性口腔黏膜炎的效果确切、安全,值得临床推广。     

A comparison of the nutrient content of uncooked and cooked lean from New Zealand beef and lamb

The composition in terms of proximate analysis, cholesterol, vitamins, minerals, and fatty acids of the lean tissue of 17 beef cuts and 18 lamb cuts was determined on within-cut composite samples (each containing lean tissue from at least 7 animals), following the knife-separation of raw and cooked cuts into lean, fat, and bone. Composite lean samples for 4 beef cuts and 4 lamb cuts were also analysed for amino-acid composition. For analysis, different cuts were the experimental unit as individual animal data were not available. The composition of lean from beef and lamb was shown to be highly desirable with a high nutrient density (mg/kJ) for many nutrients. Although lean from beef and lamb were very similar in many respects, several significant differences were detected. Changes in composition with cooking were largely eliminated when considered on a dry-matter basis, but proportions of the n-3 and n-6 polyunsaturated fatty acids increased with cooking (P < 0.05). The amino acid composition was similar for lean from beef and lamb but showed small deviations from recommended patterns for human nutrition with branched chain amino acids being limiting.     

A fast and effective method of quantitative analysis of VB1, VB2 and VB6 in B-vitamins complex tablets based on three-dimensional fluorescence spectra

Scattering signals and partial overlapping of target peaks usually appear in fluorescence determination. In this study, the improved wavelet moment method was proposed and applied to the quantitative determination of multiple target components in real B-vitamins complex tablets based on three-dimensional (3D) fluorescence spectra. The correlation coefficients (R) were more than 0.9939, and the correlation coefficients of leave-one-out cross-validation (R_LOO-cv) were more than 0.9376. The inter-day and intra-day variations were less than 5.8% and 6.1%, respectively. The recovery ranged from 97.6% to 109.4%. The limits of detection (LODs) and quantification (LOQs) were less than 0.07 μg mL⁻¹ and 0.13 μg mL⁻¹, respectively. All the statistical parameters indicated that the method was stable and reliable. The application to the practical samples confirmed that wavelet moment method effectively extracted the features of target components in 3D spectra and the proposed method could be applied to the analyses of food or other complex samples.     

Decreased blood riboflavin levels are correlated with defective expression of RFT2 gene in gastric cancer

AIM: To investigate the relationship between blood riboflavin levels and riboflavin transporter 2 (RFT2) gene expression in gastric carcinoma (GC) development.METHODS: High-performance liquid chromatography was used to detect blood riboflavin levels in patients with GC. Real-time fluorogenic quantitative polymerase chain reaction and immunohistochemistry were used to analyze the expression of RFT2 mRNA and protein in samples from 60 GC patients consisting of both tumor and normal tissue.RESULTS: A significant decrease in the RFT2 mRNA levels was detected in GC samples compared with those in the normal mucous membrane (0.398 ± 0.149 vs 1.479 ± 0.587; P = 0.040). Tumors exhibited low RFT2 protein expression (75%, 16.7%, 8.3% and 0% for no RFT2 staining, weak staining, medium staining and strong staining, respectively), which was significantly lower than that in the normal mucous membrane (10%, 16.7%, 26.7% and 46.7% for no RFT2 staining, weak staining, medium staining and strong staining, respectively; P < 0.05). Tumors with low RFT2 expression were significantly associated with tumor stage and histological grade. Moreover, a significantly decrease in Uyghur patients was observed compared with Han patients. However, other parameters-gender, tumor location and lymph node metastasis-showed no significant relationship with RFT2 expression. Blood riboflavin levels were reverse correlated with development of GC (1.2000 ± 0.97 569 ng/mL in high tumor stage patients vs 2.5980 ± 1.31 129 ng/mL in low tumor stage patients; P < 0.05). A positive correlation of plasma riboflavin levels with defective expression of RFT2 protein was found in GC patients (χ² = 2.619; P = 0.019).CONCLUSION: Defective expression of RFT2 is associated with the development of GC and this may represent a mechanism underlying the decreased plasma riboflavin levels in GC.     

Plasma homocysteine,dietary B vitamins,betaine, and choline and risk of peripheral artery disease

Objective

Few studies have examined the roles of homocysteine and related nutrients in the development of peripheral artery disease (PAD). We examined the associations between plasma homocysteine, dietary B vitamins, betaine, choline, and supplemental folic acid use and incidence of PAD.

Methods

We used two cohort studies of 72,348 women in the Nurses' Health Study (NHS, 1990–2010) and 44,504 men in the Health Professionals Follow-up Study (HPFS, 1986–2010). We measured plasma homocysteine in nested matched case–control studies of clinically recognized PAD within both cohorts, including 143 PAD cases and 424 controls within the NHS (1990–2010) and 143 PAD cases and 428 controls within the HPFS (1994–2008). We examined the association between diet and risk of incident PAD in the cohorts using a food frequency questionnaire and 790 cases of PAD over 3.1 million person-years of follow-up.

Results

Higher homocysteine levels were positively associated with risk of PAD in men (adjusted IRR 2.17; 95% CI, 1.08–4.38 for tertile 3 vs. 1). There was no evidence of an association in women (adjusted IRR 1.14; 95% CI, 0.61–2.12). Similarly, higher folate intake, including supplements, was inversely associated with risk of PAD in men (adjusted HR 0.90; 95% CI, 0.82–0.98 for each 250 μg increase) but not women (HR 1.01, 95% CI, 0.88–1.15). Intakes of the other B vitamins, betaine, and choline were not consistently associated with risk of PAD in men or women.

Conclusion

Homocysteine levels were positively associated and dietary folate intake was inversely associated with risk of PAD in men but not in women.     

核黄素反应性脂质沉积性肌病伴感觉共济失调性神经病3例报告

目的研究核黄素反应性脂质沉积性肌病伴感觉共济失调性神经病的临床、电生理、病理和基因改变特点。方法 3例男性患者来自2个家系,其中2例为兄弟,发病年龄41～43岁,主要症状是四肢肌无力,伴随双足麻木和行走不稳。查体发现四肢近端肌力下降、末梢性感觉丧失和Romberg征阳性。3例患者的血尿代谢筛查均提示存在血多种脂酰肉碱水平升高和尿戊二酸水平增高。3例患者均进行了神经电生理、肌肉活检以及电子转移黄素蛋白脱氢酶(ETFDH)基因检查,2例进行腓肠神经活检。结果 3例患者的肌电图分别出现肌源性损害、可疑神经源性损害和无异常。3例患者的四肢感觉神经传导速度显著减慢或不能引出,运动神经传导速度仅在1例出现轻度减慢。3例患者的骨骼肌均可见肌纤维内脂肪滴显著增多,2例有个别破碎红纤维,2例出现小角状肌纤维。2例患者的腓肠神经均可见有髓神经纤维中-重度减少,伴随有髓神经纤维轴索变性和再生。3例患者均携带ETFDH基因的复合杂合突变,其中2兄弟为c.65A>G和c.242T>C,另1例为c.770A>G和c.1450 T>C。结论 ETFDH基因突变导致的核黄素反应性脂质沉积性肌病可以伴随感觉共济失调性神经病。