Insulin-like growth factor I reduces the occurrence of necrotizing enterocolitis by reducing inflammatory response and protecting intestinal mucosal barrier in neonatal rats model.

OBJECTIVE: To observe the effect of enteral supplement of insulin-like growth factor I (IGF-1) on dynamic changes of TLR4, NF-κB, IL-6, SIgA and MUC2 in intestinal tissues of neonatal rats, and to investigate the protective effects and possible mechanisms of IGF-1 on necrotizing enterocolitis (NEC). MATERIALS AND METHODS: Specific pathogen free (SPF) neonatal Sprague Dawley (SD) rats aged 3 days old were randomly divided into 3 groups, namely, normal control group, NEC model group and IGF-1 intervention group. In NEC group, the neonatal NEC rat models were established using artificial feeding, hypoxia and cold stimulation. In IGF-1 intervention group, the models were established by means of artificial feeding plus hypoxia and cold stimulation, and IGF-1 (22 ug/L) at a physiological concentration similar to the breast milk was added to milk replacer for intervention. The rats in the three groups were killed after the blood was collected from the heart at 24, 48 and 72 h, respectively, following the establishment of models; then, 3 cm of the terminal ilea were dissected and used for histopathological examination, RT-PCR and ELISA studies after hematoxylin and eosin (HE) staining. RESULTS: Symptoms in IGF-1 intervention group were significantly relieved, and the incidence rate of NEC was lowered remarkably. In NEC model group, the peak expression of TLR4 mRNA occurred later than that of NF-κB mRNA and IL-6, and the expressions of TLR4 mRNA, NF-κB mRNA and IL-6 were decreased at 72 h after IGF-1 intervention. In NEC model group, the expression of MUC2 showed a transient decrease, the expression of SIgA was on the decline, but the expressions of MUC2 and SIgA were increased after IGF-1 intervention. CONCLUSIONS: The enteral administration of IGF-1 at a physiological concentration can ameliorate the clinical symptoms in neonatal NEC rat models and decrease the occurrence rate. The possible mechanism is that IGF-1 down-regulates the TLR4 mRNA expression to inhibit the production of inflammatory mediators, and it up-regulates the expressions of MUC2 and SIgA to protect the mechanical and immuno-barrier functions of the intestinal mucous.

Production of secoisolariciresinol from defatted flaxseed by bacterial biotransformation.

AIMS: Secoisolariciresinol (SECO) is increasingly recognized for potential clinical application because of its preventive effects against breast and colon cancers, atherosclerosis and diabetes, and its production through biotransformation has been attempted. However, previously reported bacteria all required stringent anaerobic culture conditions, precluding large-scale production. Here, we report the isolation and characterization of bacteria that produce SECO under less stringent anaerobic culture conditions. METHODS AND RESULTS: Using defatted flaxseed as raw material, we isolated a facultative anaerobic bacterium from human faeces that hydrolysed secoisolariciresinol diglucoside-3-hydroxy-3-methyl glutaric acid (SDG-HMGA) oligomers in flaxseed to produce SECO. Both conventional assays and 16S rRNA gene sequence analysis demonstrated its close relatedness with Bacteroides uniformis. The transformation efficiency of SDG in defatted flaxseed to SECO was more than 80% by this bacterial strain. We investigated factors that might influence fermentation, such as redox potential and pH, for large-scale fermentation of defatted flaxseed to produce SECO. CONCLUSIONS: The method to produce SECO through biotransformation of defatted flaxseed with this bacterial strain is highly efficient and economic. SIGNIFICANCE AND IMPACT OF THE STUDY: This bacterial strain can transform SDG to SECO under less stringent anaerobic culture conditions, which will greatly facilitate industry-scale production of SECO.

p73 expression and its clinical significance in colorectal cancer.

OBJECTIVE: To explore p73 mRNA and p73 protein expression and their clinical significance in colorectal cancer. METHOD: p73 mRNA and p73 protein expression were detected using hybridization in situ and immunohistochemical method in cancerous tissue from 60 patients of colorectal cancer and in paracancerous tissue from 23 patients among the corresponding 60 patients of colorectal cancer. Quantitative analysis was performed using Smartscape image analysis system. RESULTS: Compared with paracancerous tissue, p73 mRNA and p73 protein expression in cancerous tissue was increased with a statistically significant difference (P < 0.01) and was associated with differentiation level and lymphatic metastasis. CONCLUSION: High expression of p73 mRNA and p73 protein in colorectal cancer may be involved in the progression of colorectal cancer and p73 mRNA and p73 protein may serve as a potential index to predict differentiation level and prognosis of colorectal cancer.

Application of independent component analysis to dynamic contrast-enhanced imaging for assessment of cerebral blood perfusion.

Dynamic contrast-enhanced (DCE) imaging is widely used for in vivo assessment of the cerebral blood perfusion. In this work, we investigate the use of independent component analysis (ICA) on DCE imaging data for assessment of cerebral blood perfusion, without any prior knowledge of the underlying tissue vasculature and arterial input function. The minimum description length (MDL) criterion and principle component analysis (PCA) were employed to reduce the dimension of the data. An oscillating index method was used to select the components of interest. Numerical simulation and patient case studies were carried out to investigate the performance of ICA. The results show that ICA is able to extract physiologically meaningful components from the DCE imaging data. The advantages of ICA include its efficiency of computation, clarity of obtained component maps, and no need of the manually selected input function. The obtained independent component maps can provide reliable reference to identify the arterial and venous structure, and allow better demarcation of the tumor territories. The potential of ICA to be a useful clinical tool for diagnosis of cerebral vascular disease and for the assessment of treatment response has been demonstrated.

An investigation of adolescent health from China.

In a senior high school in the Weicheng District of Weifang City, we studied the health of a total 445 students. The age of the first emission was 15.22 +/- 2.24 years, and the age of menarche was 13.56 +/- 2.26 years. Because 47.9% of boys and 63.8% of girls did not have previous knowledge about puberty, 39.9% of boys and 52.2% of girls felt puzzled and disgusted with the onset of puberty. About 18% of boys and about 2% of girls reported masturbation. The average frequency of masturbation was 3.5 times a month in the boys and two times monthly in girls. Adolescents acquired sexual knowledge and information predominantly from magazines (25.8% of boys and 28.0% of girls). About 64% of boys and 44% of girls wanted to be given educational programs on sex. About 43% of boys and 1% of girls smoked cigarettes and 83.5% of boys and 54.9% of girls drank alcohol. The survey suggested that it is essential to teach the senior high school students about the psychosocial and behavioral characteristics of adolescence and promote research on adolescent medicine.

PIP: 163 male and 282 female students aged 10-18 years during 1993-94 at a senior high school in the Weicheng District of Weifang City completed questionnaires on their sex-related knowledge and behavior. 41% of boys and 10% of girls did not answer the question on age at first semen emission and menarche, respectively. However, of those who did respond to the question, the mean age at first emission was 15.22 years and the age of menarche was 13.56 years. 34% of boys and 25% of girls were confused by the onset of puberty; 47.9% of all boys and 63.8% of all girls had no previous knowledge of puberty. Approximately 18% of boys and 2% of girls reported masturbation, although 20% and 18% of the entire sample, respectively, provided no response to the question on masturbation. The boys and girls who admitted to masturbating did so an average of 3.5 and 2 times per month, respectively. Masturbation has long been considered an obscene, sinful behavior in China. All participants denied having sexual intercourse. 25.8% of boys and 28.0% of girls acquired their sexual knowledge and information from magazines, and 64% of boys and 44% of girls wanted educational programs on sex. 43% of boys and 1% of girls smoked cigarettes and 83.5% of boys and 54.9% of girls drank alcohol.

[Cytotoxicity of human lymphokine-activated killer cells against mitotic phase tumor cells].

To improve LAK/IL-2 efficiency in tumor immunotherapy, the cytotoxicity of human LAK cells against mitotic phase of human lung adenocarcinomas Anip 973 cells was studied in vitro. Anip 973 cells were synchronized by the specific mitotic phase antitumor drug vincristine (VCR). The differences in morphology between mitotic tumor cells and normal tumor cells were observed by light microscopy and transmission electronmicroscopy. The cytotoxicity of human LAK cells against mitotic phase Anip973 cells was significantly increased in standard 4-hour 51Cr release assay. In scanning and transmission electronmicroscopies, LAK cells were in close contact with target cells in the form of interdigitate of microvilli and protrusions structure. The form of death of mitotic phase tumor cells was lytic necrosis and apoptosis.