人表皮干细胞体外分选和培养对构建组织工程皮肤种子细胞的可能性

目的:探讨人表皮干细胞在体外分选和培养的可能性,为构建组织工程皮肤寻找理想的种子细胞。方法:实验于2002-01/12在中山大学基础医学院动物中心完成。根据表皮干细胞与Ⅳ型胶原蛋白的高黏附的特性,运用黏附实验将干细胞从培养在鼠Ⅳ型胶原包被的培养瓶的表皮细胞中分选出来,并从形态学、超微结构及免疫组化等方面进行了鉴定。结果:分选出来培养的细胞符合表皮干细胞的特征,说明分选培养的细胞是表皮干细胞。结论:预先在体外对表皮干细胞进行分选和培养是可行的,该细胞群有望成为构建组织工程皮肤的种子细胞,为下一步应用表皮干细胞构建组织工程皮肤奠定了牢固的基础。     

Molecular prenatal diagnosis in 2 pregnancies at risk for spondyloepiphyseal dysplasia congenita

BACKGROUND: Spondyloepiphyseal dysplasia congenita (SEDC) is an autosomal dominant skeletal dysplasia characterized by short stature, abnormal epiphyses, and flattened vertebral bodies. Secondary prevention of SEDC can be achieved by prenatal diagnosis. Reports of antenatally-diagnosed SEDC fetuses have been very rare and molecular prenatal diagnosis even rarer. We previously reported a familial G504S mutation in the type II collagen (COL2A1) gene resulting in SEDC. In this study, molecular prenatal diagnosis was performed to 2 couples in this family with pregnancies at risk for SEDC. METHODS: Amniotic fluid was sampled by amniocentesis under ultrasound guidance at 19+3 and 18+6 weeks' gestation, respectively. Karyotype and molecular genetic analysis were performed on cultured amniotic fluid cells. Maternal cell contamination was excluded by short tandem repeat (STR) analysis. Direct DNA sequencing and DHPLC were conducted to detect the potential mutation in exon 23 of COL2A1 gene. Both women underwent serial sonograms because they insisted that the molecular diagnosis should be confirmed by another method, although they had been informed that mutation analysis is predictive of the disease. RESULTS: Karyotype of both fetuses was normal and molecular genetic analysis revealed that fetus 1 carried a G504S mutation in exon 23, while fetus 2 was normal. In case 1, femur length of the fetus was markedly below the 5th centile at 23 weeks' gestation, which confirms the accuracy of molecular diagnosis. A medical termination was carried out at 27+5 weeks' gestation and a male fetus with a relatively large head and short limbs was delivered. The fetal radiograph demonstrated a number of features, including generalised platyspondyly, absent ossification of the vertebral bodies in the cervical region and significant shortening of the long bones. The diagnosis of SEDC was thus confirmed clinically. Ultrasound monitoring of fetus 2 showed that its femur length was normal for gestational age at repeated scans, which was consistent with the molecular diagnosis. CONCLUSIONS: Molecular analysis allows early and accurate prenatal diagnosis for SEDC once mutation is known in a family. However, considering the poor genotype/phenotype correlation in many cases of SEDC, the combination of ultrasound as well as molecular genetic approach might be needed.     

Diagnostic performance of diffusion-weighted magnetic resonance imaging in differentiating human renal lesions (benignity or malignancy): a meta-analysis

Purpose

This study aims to quantitatively evaluate the potential of diffusion-weighted magnetic resonance imaging (DW-MRI) for differentiating malignant and benign human renal lesions.

Materials and methods

A systematic literature was performed to identify previous research related to the diagnostic performance of DW-MRI for determining whether human renal lesions were benign or malignant. ADC values were extracted from normal renal tissue and different lesion types. Data were extracted to assess the diagnostic performance of DW-MRI for differentiating malignant and benign human renal lesions, as well as running threshold effect and heterogeneity.

Results

Nine publications with 11 subsets were eligible for data extraction and diagnostic performance calculation. A total of 988 apparent diffusion coefficient (ADC) measurements were included. The differences in ADC values between benign lesions (2.47 ± 0.81 × 10^?3 mm²/s) and malignant lesions (1.81 ± 0.41 × 10^?3 mm²/s) were statistically significant (P < 0.001). The diagnostic odds ratio, the overall positive, negative likelihood ratios, pooled weighted sensitivity and specificity with 95% CI were 20.05 (95% CI 12.56–32.02), 3.32 (95% CI 2.13–5.18), 0.20 (95% CI 0.15–0.27), 88% (95% CI 0.84–0.91) and 72% (95% CI 0.67–0.76), respectively. The area under the curve of the summary receiver operating characteristic was 0.90.

Conclusions

This meta-analysis indicated that DW-MRI had a relatively good diagnostic accuracy in differentiating malignant and benign human renal lesions. We preliminarily recommend that DW-MRI is performed with a maximum b value ranging from 800 to 1000 s/mm² at 3.0 T for imaging protocol, and that DW-MRI should be used with caution when the study population includes children.

     

瑞易宁对2型糖尿病病人血清IGF-1的影响

目的 :探讨瑞易宁对 2型糖尿病病人血清胰岛素样生长因子 1(IGF 1)的影响。方法 :IGF 1由IRMA法测定。糖尿病病人空腹血清IGF 1与对照组比较 ,瑞易宁治疗前后IGF 1水平比较。结果 :糖尿病组治疗前IGF1 1水平较对照组下降 (P <0 .0 5 ) ,经瑞易宁治疗 4周后IGF 1水平升高。结论 :瑞易宁可改善 2型糖尿病病人血清IGF 1的水平。     

骨髓间充质干细胞定向诱导条件下向脂肪细胞和成骨细胞诱导分化的关系

目的：观察骨髓间充质干细胞在定向诱导分化条件下向成骨细胞、脂肪细胞分化的特征及相互关系。方法：实验于2004-10／2005-04在泸州医学院心肌电细胞实验室完成。日本大耳兔10只，经兔髂嵴无菌抽取骨髓，采用Percoll液进行梯度离心法和体外细胞贴壁分离培养法相结合对兔骨髓间充质干细胞进行分离、纯化，将获得的原代和传代培养的骨髓间充质干细胞，分别用含成脂诱导剂和含成骨诱导剂的改良的伊格尔培养基进行实验组（向脂肪细胞和成骨细胞的定向诱导培养，对诱导培养后的细胞进行生长形态学特征观察），对照组（采用不加成脂、成骨诱导剂的伊格尔培养基），两组进行成脂及成骨诱导后的苏丹脂肪染色、碱性磷酸酶活性检测、胞外矿化基质测定，并进行细胞成脂和成骨率比较。结果：从10只实验动物中均成功提取到骨髓间充质干细胞，其中有2只动物的骨髓间充质干细胞在原代培养时出现污染，8只获得成功进入结果分析。①在经过2ld成脂诱导培养后实验组的许多细胞胞浆内均出现较多的高折光性的脂滴，苏丹脂肪染色呈橘红色，同时Kossa法也检测出少许成骨分化，其比例为70％（28／40）干细胞可转化为含有脂滴的脂肪细胞；10％（4／40）干细胞转化为含有钙结节的成骨细胞。②经过21d向成骨诱导培养后实验组出现一些细胞基质逐渐堆积、并出现基质矿盐沉积，Von Kossa法测定形成的钙结节，同时苏丹脂肪染色也检测出少许向脂肪细胞分化，其比例为40％（16／40）干细胞可转化为成骨细胞，20％（8／40）骨髓间充质干细胞可转化为脂肪细胞。③对照组用苏丹脂肪染色后显示5％（2／40）骨髓间充质干细胞分化为脂肪细胞，用Von Kossa法测定矿化结节形成比例和碱性磷酸酶活性测定结果成骨率10％（4／40）。结论：在适当诱导条件下骨髓间充质干细胞可一部分转化为脂肪细胞，另一部分转化为成骨细胞，两者分化存在一定关系：分化的脂肪细胞多，则成骨细胞少；分化的成骨细胞多，则脂肪细胞少。     

应用护理程序对脑卒中患者实施系统健康教育临床效果观察

目的：提高脑卒中患者自我护理能力，增强其自我保健意识，提高患者生活质量。方法：实验组实施系统的健康教育并与对照组在有关疾病知识掌握程度、对护理工作满意度等方面进行对比研究。结果：患者有关脑卒中知识掌握程度较对照组明显提高（P〈0．01），对护理工作满意度明显提高（P〈0．01）。结论：实施系统健康教育可有效提高患者对脑卒中的认识水平，增强其自我护理能力，对疾病康复起到了一定的促进作用。     

注重输液观察记录卡书写质量防范护理纠纷

目的探讨输液观察记录卡书写环节质量控制、防范护理纠纷.方法随机抽查输液观察记录卡2 500份,分成2组,2000年1 200份为对照组,2001年1 300份为观察组.结果观察输液记录书写合格率;不同项目书写合格率;书写项目不符合要求,出现护理纠纷等项目,2组经χ2检验(P<0.05),差异有显著性.结论注重输液观察记录卡书写环节质量控制,防范护理纠纷是行之有效的方法,在护理工作中应予重视.     

格林-巴利综合征并重症肝炎患者的观察及护理

目的:探讨格林-巴利综合征(GBS)患者度过危险期,减少病死率的护理对策。方法:对1例格林-巴利综合征患者进行严密的病情观察和精心护理。结果:患者痊愈,肢体功能恢复,生活质量提高。结论:密切观察病情和优良的护理是保证治疗抢救成功的关键。     

格林-巴利综合征并重症肝炎患者的观察及护理

目的：探讨格林-巴利综合征（GBs）患者度过危险期，减少病死率的护理对策。方法：对1例格林-巴利综合征患者进行严密的病情观察和精心护理。结果：患者痊愈，肢体功能恢复，生活质量提高。结论：密切观察病情和优良的护理是保证治疗抢救成功的关键。