转基因食品的快速PCR鉴定

用十六烷基-二甲基-乙基-溴化铵(CTAB)法快速高效地从样品中提取了可供分析的基因组DNA,经PCR扩增,鉴定了含有35S启动子和NOS终止子的转基因样品.该方法的灵敏度可达0.1%,并且具有很好的稳定性.     

早期饮食干预对婴幼儿呼吸道变态反应疾病的影响

目的 观察早期饮食干预对婴幼儿呼吸道变态反应疾病发展的影响。方法 选取2003年1月-2004年6月复旦大学附属儿科医院0～6月变态反应疾病高危婴儿176例，在进行环境控制的前提下，随机分为干预组（饮食干预）和非干预组，随访两组患儿变态反应疾病发生、发展的情况。结果 （1）在干预6、12、18个月后，干预组发生两种以上变态反应疾病的人数均显著少于非干预组，过敏症状的严重程度较非干预组也显著减轻（P〈0．005）。（2）饮食干预18个月后，两组患儿在吸入性过敏原筛查阳性比例上的差异没有显著性（χ^2=0．002，P=0．969），但干预组患儿的肺功能显著优于非干预组（P〈0．005）、干预组的食物过敏原筛查阳性比例显著低于非干预组（χ^2=8．91，P〈0．01）。结论 对变态反应性疾病高危婴儿进行饮食干预，能减轻或消除呼吸道变态反应疾病症状，改善肺功能。     

Central fat predicts deterioration of insulin secretion index and fasting glycaemia: 6-year follow-up of subjects at varying risk of Type 2 diabetes mellitus.

AIMS: To examine the relationships between body composition and changes in fasting glycaemia, and in indices of insulin secretion and insulin action over 6 years in females with a family history of Type 2 diabetes with or without prior gestational diabetes ('at risk' group, AR) and control females (control group, C). METHODS: At baseline and at follow-up, an oral glucose tolerance test and dual energy X-ray absorptiometry assessment of body composition were performed. Indices of insulin resistance (HOMA R') and insulin secretion (HOMA beta') were obtained from fasting insulin and glucose concentrations. RESULTS: At baseline, the groups were similar for age, body mass index, fasting levels of plasma glucose and insulin, HOMA R' and HOMA beta'. Despite similar total body fatness, AR had significantly greater waist circumference and central fat (both P < 0.02) compared with C. At follow-up there was a significant increase in central adiposity only in AR, and the fasting plasma glucose (FPG) level was higher in AR compared with C (5.0 +/- 0.2 vs. 4.3 +/- 0.2 mmol/l, P = 0.02). This rise in plasma glucose in AR was related to a decline in HOMA beta' (r = 0.45, P = 0.0065). Both the baseline and the increments in total and central abdominal fat mass were associated with the time-related decline in HOMA beta'. CONCLUSIONS: Six years after initial assessment, AR showed deterioration in FPG levels due predominantly to a decline in insulin secretion index without major change in insulin resistance index. Importantly, baseline body fatness (especially central adiposity), as well as increases in fatness with time, were the major predictors of the subsequent decline of insulin secretion index and the consequent rise in FPG.     

Allergic reactions to raw, pasteurized, and homogenized/pasteurized cow milk: a comparison

Five children aged 12-40 months with IgE-mediated adverse reactions to cow milk (immediate onset clinical pattern of cow milk allergy) were orally challenged double-blind in random order with three different milk preparations processed from the same batch of milk 1) raw untreated cow milk, 2) pasteurized cow milk, 3) homogenized and pasteurized cow milk, and 4) Nutramigen (a commercial hypoallergenic infant formula based on hydrolysed casein) as placebo. Skin prick tests with the same preparations were also performed. On oral challenge the three different processed milk types provoked significant and similar allergic reactions in each child, and no adverse reactions followed the challenge with placebo (Nutramigen). Skin prick test with the same milk products were positive in all children and comparable to the results with an extract of purified raw cow milk protein (Soluprick), whereas Nutramigen did not elicit any skin reactions. A tendency towards a lower threshold of reaction and larger skin reactions induced by the processed milk preparations might indicate an increased ability of pasteurized and homogenized/pasteurized milk to evoke allergic reactions in patients allergic to milk.     

Evaluation of allergenicity of genetically modified soybean protein extract in a murine model of oral allergen-specific sensitization

Background With the development of genetically modified crop plants there has been a growing interest in the approaches available to assess the potential allergenicity of novel gene products. For additional assessment of the potential allergenicity of expressed proteins, informative data can be generated using animal models. Soybean is one of the major source of protein in human and animal nutrition, and has also been well characterized as a major allergenic source. Advances in biotechnology have resulted in an increasing number of genetically engineered foods, and among these soybean is one of the most widespread. Objective To develop and characterize a murine model of IgE‐mediated soybean sensitization induced by intragastric immunization, in the presence of Cholera Toxin, with wild‐type soybean extract (wt‐SE) or with genetically modified soybean extract (gm‐SE). Methods Balb/c mice born in our animal facilities, from females fed on soy‐free food, were fed with the same soy‐free food and used in all the experiments. Mice were sensitized by gavages with soybean extracts, and allergen‐specific IgE and IgG responses were studied by direct ELISA and ELISA inhibition. Antigen‐specific cell proliferation and cytokine production were evaluated in spleen cell cultures. Results Sensitization with both soybean extracts induced high levels of antigen‐specific IgE and IgG1 and low levels of specific IgG2a. Both wt‐SE and gm‐SE were able to inhibit the binding of specific IgE from mice immunized with gm‐SE to the same antigen used for the ELISA coating. A comparable proliferative response was obtained with the homologous as well as with the heterologous extracts. Conclusion In sensitized mice, we observed a predominantly T‐helper type 2 (Th2)‐type immune response, with increased soybean‐specific IgE and IgG1 antibodies and a concomitant increase of IL‐4 and IL‐5 production. Results obtained by specific IgE ELISA inhibition and by antigen‐specific T cell proliferation demonstrated that wt‐SE and gm‐SE shared B and T epitopes. The present murine model of soybean sensitization established by the oral route should provide valuable information about risk assessment for food allergy from new proteins of genetically modified foods.     

少、弱精子症中精子形态缺陷类型及发生率的检查分析报告

目的 探讨在少、弱精子症中精子形态缺陷类型及其发生率.方法 对精液常规和改良巴氏染色检查的结果进行统计学分析.结果 （1）男性不育症中畸形精子症的发生率约为75%;精子头部缺陷的发生率约为70%,各种头部缺陷中空泡头畸形的发生率占首位,约为20%.（2）少精子症患者的正常形态精子百分率的中位数约为2.97%（P=0）,弱精子症患者的中位数为6.67%（P=0.003）.结论 （1）精子头部缺陷是精子畸形的主要类型;（2）少、弱精子症的畸形精子比例升高;（3）精子形态缺陷分析对选择辅助助孕方式具有应用价值.     

One-year outcome after first-ever stroke according to stroke subtype, severity, risk factors and pre-stroke treatment. A population-based study from Tartu, Estonia

The aim of the current study was to evaluate the outcome at 1 year following a first-ever stroke based on a population-based registry from 2001 to 2003 in Tartu, Estonia. The outcome of first-ever stroke was assessed in 433 patients by stroke risk factors, demographic data and stroke severity at onset using the Barthel Index (BI) score and the modified Rankin Score (mRS) at seventh day, 6 months and 1 year. Female sex, older age, blood glucose value >10 mmol/l on admission and more severe stroke on admission were the best predictors of dependency 1 year following the first-ever stroke. At 1 year, the percentage of functionally dependent patients was 20% and the survival rate was 56%. The use of antihypertensive/antithrombotic medication prior to stroke did not significantly affect the outcome. The survival rate of stroke patients in Tartu is lower compared with other studied populations. The outcome of stroke was mainly determined by the initial severity of stroke and by elevated blood glucose value on admission. Patients with untreated hypertension had more severe stroke and trend for unfavourable outcome compared with those who were on treatment.     

Renal acid excretion in early infancy

In early infancy, complex disorders of acid base metabolism are more frequent than in any other age group, with a predisposition to metabolic acidosis due to an age-related low renal capacity for acid excretion and an unphysiologically high actual renal acid load in nutrition with common formulas. Recently in preterm and small-for-gestational-age infants, persistent maximum renal net acid excretion (NAE) with subnormal or normal blood acid base status, impaired weight gain, and adaptive hormonal reactions have been observed. Incipient late metabolic acidosis is one example of a mixed disorder of acid base metabolism with maximum renal NAE in early infancy. Alkali therapy is highly effective and can be realized both on an individual basis, using urine pH screening as a diagnostic criterium for maximum renal acid stimulation, or on a general preventive level using modified standard formula with a reduced actual renal NAE similar to that seen on alimentation with human milk. From an integrated point of view, the low glomerular filtration rate and renal capacity for acid excretion beyond the developmental age of more than 44 weeks, may well be interpreted as the result of a specific adaptation to breast feeding sparing energy, and thus an evolutionary advantage for the survival of mother and child. Received July 10, 1996; received in revised form and accepted October 7, 1996     

Inter-rater reliability of the original and modified Barthel Index,and a comparison with the Functional Independence Measure

The Barthel Index (BI), the Modified Barthel Index (MBI) and the Functional Independence Measure (FIM) are all widely used by occupational therapists as assessment tools for clinical decision-making and outcome measurement. All of these tools have demonstrated validity and the BI and the FIM have demonstrated inter-rater reliability. The MBI has been modified to increase sensitivity; however, there have been no publications on the inter-rater reliability of this tool following the changes. The purpose of this research was to examine the inter-rater reliability of two versions of the Barthel Index, and draw some comparisons between this assessment tool and the FIM. Twenty-five patients with neurological and orthopaedic conditions were assessed by three occupational therapists using the three tools. The method of analysis selected was percentage agreement and intraclass correlation coefficient. The results indicated that both the original and modified versions of the Barthel Index possess good inter-rater reliability. As all three tools have demonstrated adequate reliability and validity, it is suggested that clinicians select the most sensitive tool that best meets their clinical needs, and use this assessment tool in its standardized format.     

Adhesion inhibitory activity of β-lactoglobulin isolated from infant formulae

β-Lactoglobulin was isolated from infant formulae that were ultra high temperature (UHT) -treated, sterilized or spray-dried. The effect of the isolated β-lactoglobulin on SfaII-fimbriae-mediated adhesion of Escherichia coli to human ileostomy glycoproteins was studied in vitro. β-Lactoglobulin isolated from sterilized formulae was found to perform significantly less well than preparations from spray-dried formulae (p = 0:05). Great heterogeneity was observed in the adhesion inhibitory capacity of β-lactoglobulin isolated from UHT-treated formulae. Therefore, no significant difference was observed between UHT-treated and sterilized formulae or spray-dried formulae (p < 0:10). It can be hypothesized that β-lactoglobulin from spray-dried and some UHT-treated infant formulae may affect the colonization of mucous membranes by E. coli strains causing neonatal septicaemia and meningitis.