Little information regarding the composition of the gut microbiota in preterm infants is available. The purpose of this study was to investigate the bacterial diversity in faeces of preterm infants, using analysis of randomly cloned 16S rRNA genes and PCR-TTGE (temporal temperature gradient gel electrophoresis) profiles, to determine whether noncultivated bacteria represented an important part of the community. The 288 clones obtained from faecal samples of 16 preterm infants were classified into 25 molecular species. All but one molecular species had a cultivated representative in public databases: molecular tools did not reveal any unexplored diversity. The mean number of molecular species per infant was 3.25, ranging from one to eight. There was a high interindividual variability. The main groups encountered were the Enterobacteriaceae family and the genera Enterococcus, Streptococcus and Staphylococcus. Seven preterm infants were colonized by anaerobes and only four by bifidobacteria. TTGE profiles were composed of one to nine bands (mean value: 4.3). Furthermore, 51 of 59 clones (86%) comigrated with a band of the corresponding faecal sample. This study will form a comparative framework for other studies, e.g. on the faecal microbiota of preterm infants with different pathologies or the impact of diet on colonization. 相似文献
The goal of the present study was to prospectively assess the plasma selenium (Se) concentrations of term and preterm infants during the first year of life in relation to gestational age and nutrition.
Blood specimens were collected from orally formula-fed preterm infants (gestational age < 32 weeks, birth weight < 1500 g): 1.) in hospital and 2.) corrected for gestational age parallel to healthy term breast and formula-fed infants at the ages of 1, 4 and 12 months. All infants were fed according to a standardized nutritional concept, solids and follow-up formula were introduced at the age of 4 months.
Plasma selenium in preterm infants in hospital was 11.7 (6.5–20.8) g/l and 11.6 (8.8–16.7) g/l at 4 weeks corrected for gestational age. At the age of 4 months plasma selenium was still significantly lower than in the other groups: Preterm infants: 17.1 (10.4–30.5) g/l; formula-fed term infants: 31.3 (24.3–47.5) g/l; breast-fed term infants: 45.6 (27.1–65.1) g/l). The levels of breast-fed infants were significantly higher than those of both formula-fed groups up until the introduction of solids.
Preterm infants had significantly low plasma selenium levels up until a postnatal age of at least 6 months. The levels were lower than those of term infants fed an identical unsupplemented infant formula during the first 4 months of life. These data support routine monitoring in hospital and selenium supplementation of preterm infants, preferably in hospital before discharge. 相似文献
In this study the effects of gene targeting procedures on the early behaviour and morphological development of the resulting offspring have been investigated. Six groups of mice, each having undergone a specific aspect of the biotechnological procedure, (including electroporation, microinjection and/or embryo culture) and one control group, were compared. Development of behaviour, morphological characteristics and body weight of the progeny were tested daily from birth to weaning (0–3 weeks) for all groups. No significant differences in behaviour or morphological development were observed. However, the occurrence of increased (perinatal) pup mortality and increased body weight in the procedural groups, indicates that during the production of gene targeted mice, some of the normal physiological and/or developmental processes can be affected. Therefore, gene targeting procedures should always be accompanied by careful monitoring of health and welfare of the resulting offspring. 相似文献
AbstractCurrently, bronchopulmonary dysplasia (BPD) occurs almost exclusively in pre-term infants. In addition to prematurity, other factors like oxygen toxicity and inflammation can contribute to the pathogenesis. This study aimed to compare urinary inflammatory and oxidative stress markers between the no/mild BPD group and moderate/severe BPD group and between BPD cases with significant early lung disease like respiratory distress syndrome (RDS) (‘classic’ BPD) and with minimal early lung disease (‘atypical’ BPD). A total of 60 patients who were a gestational age < 30 weeks or a birth weight < 1250 g were included. Urine samples were obtained on the 1st, 3rd and 7th day of life and measured the levels of leukotriene E4 (LTE4) and 8-hydroxydeoxyguanosine (8-OHdG). The 8-OHdG values on the 3rd day showed significant correlation to duration of mechanical ventilation. The 8-OHdG levels on the 7th day were the independent risk factor for developing moderate/severe BPD. In ‘classic’ BPD, the 8-OHdG values on the 3rd day were higher than those of ‘atypical’ BPD. In ‘atypical’ BPD, the LTE4 values on the 7th day were higher than the values in ‘classic’ BPD. These results suggest that oxidative DNA damage could be the crucial mechanism in the pathogenesis of current BPD and the ongoing inflammatory process could be an important mechanism in ‘atypical’ BPD. 相似文献
Secretory immunoglobulin A (IgA) is known to play an important role in the mucosal defense against a variety of pathogens. Although the role of IgA antibodies during sexual transmission of HIV is not clear, HIV-specific IgA antibodies have been detected in various mucosal secretions of HIV-infected individuals. Using a monoclonal antibody against human IgA, we established an ELISA system to detect anti-HIV p24 IgA antibodies in sera and saliva. We have analyzed the levels of anti-HIV p24 IgG and IgA antibodies in sera and saliva of 107 and 119 adults, respectively, with HIV infection at different clinical stages, and in the sera of 13 infants born to HIV-infected mothers. The level of anti-HIV p24 IgA antibodies was lower in sera and higher in saliva as compared to that of anti-HIV p24 IgG antibodies. Where the percentage of HIV-specific serum antibody-positive cases decreased with disease progression, that of saliva antibody-positive cases increased in AIDS patients. Among the 13 infants born to HIV-infected mothers, 7 infants were HIV-p24-specific serum IgA positive. These sera were negative for anti-HIV p24 secretory IgA, suggesting that some infants develop their own immune responses against HIV infection. Thus, the detection of HIV-specific IgA antibodies, especially in saliva, could be a simple and reliable test for the diagnosis of HIV infection. 相似文献