ABSTRACT
Objective To explore the suicide intention and its influential factors among primary and junior high school students in rural areas of Anhui province,in order to provide evidence for early intervention related to mental health problems.Methods All students from 3 junior high and 5 primary schools in Changfeng county of Anhui were recruited as the study subjects using the cluster sampling method.Data were collected by using Children' s Depression Inventory,the Family APGAR Index,the Trait Coping Style Questionnaire,the Children' s Self-Esteem Scale,Social Anxiety Scale for Children,and the Quality of Life Scale.Chi-square test and Logistic regression were used to analyze the suicidal ideation and its influential factors respectively.Results 8.64％ (252/2917) of the studied children had suicidal ideation.Out of them,9.80％ (166/1694) and 7.03％ (86/1223) were left-behind or non-left-behind children.There was statistically significant difference on suicide ideation between the left-behind children and non-left-behind children (P=0.015).Data from the multivariate logistic regression analysis showed that social anxiety and negative coping style were the risk factors for suicidal ideation (P ＜0.05) while better family function and quality of life were the protective factors of suicidal ideation (P＜0.05).Conclusion Suicide ideation was relatively prevalent among rural children in Anhui province.Family,school and society should carry out different kinds of preventive measures to prevent suicide related behaviors in children from this area.
ABSTRACT
The Monascus mutant with high yield of yellow pigment was obtained by using conventional relevant mutation techniques, e.g., treating with physical mutagens(such as UV light) and chemical sub- stances (such as N-methyl-N'-nitro-N-nitrosoguanidine). The yellow pigment was scanned from 300 nm to 600 nm with UV spectrometer, the maximal absorption was determined at 410 nm. The growth characteristic of Monascus mutant is stable, the yellow pigment value and colour hue in liquid fermentation can reach 100 U/mL and 3.5 respectively. The yellow pigment is stable from pH 3 to pH 8, but the precipitation appeared as the pH of the pigment solution lower than 3.
ABSTRACT
<p><b>BACKGROUND</b>Recent studies have suggested that mature T cells can change their specificity through reexpression of recombination-activating genes (RAG) and RAG-mediated V(D)J recombination. This process is named receptor revision and has been observed in mature peripheral T cells from transgenic mice and human donors. However, whether thebreceptor revision in mature T cells is a random or orientated process remains poorly understood. Here we used the Jurkathuman T cell line, which represents a mature stage of T cell development, as a model to investigate the regulation of Tcell receptor (TCR) gene recombination.</p><p><b>METHODS</b>TCR Dbeta-Jbeta signal joint T cell receptor excision DNA circles (sjTRECs) were determined by nested and seminested PCR. Double-strand DNA breaks at recombination signal sequences (RSSs) in the TCRVbeta chain locus were detected by ligation-mediated-PCR. Further analysis of the complementarity-determining region 3 (CDR3) size of the TCRVbeta chain was examined by the TCR GeneScan technique.</p><p><b>RESULTS</b>RAG1, RAG2, and three crucial components of the nonhomologous DNA end-joining (NHEJ) pathway were readily detected in Jurkat. Characteristics of junctional diversity of Dbeta2-Jbeta2 signal joints and ds RSS breaks associated with the Dbeta2 5' and Dbeta 2 3' sites were detected in DNA from Jurkat cells. CDR3 size and the gene sequences of the TCRVbeta chain did not change during cell proliferation.</p><p><b>CONCLUSIONS</b>RAG1 and RAG2 and ongoing TCR gene recombination are coexpressed in Jurkat cells, but the ongoing recombination process may not play a role in modification of the TCR repertoire.However, the results suggest that Jurkat could be used as a model for studying the regulation of RAGs and V(D)J recombination and as a "special" model of the coexistence of TCR gene rearrangements and "negative" receptor revision.</p>