An epidemiological survey on paragonimiasis in Jin Miaopu township in Shanxi province / 中华预防医学杂志

<p><b>OBJECTIVE</b>To investigate the epidemiological factors and tendency of paragonimiasis in Jin Miaopu township in Zezhou county of Shanxi Province, and to understand the current status of public awareness for providing references to paragonimiasis education and prevention.</p><p><b>METHODS</b>A questionnaire survey was conducted among 2172 villagers probing awareness of paragonimiasis and their experiences of eating crabs; Infection screening and antibody test were also performed by means of ELISA.</p><p><b>RESULTS</b>The paragonimiasis knowledge coverage rate was zero, and 67.7% (1471/2172) of the respondents claimed their histories of crab eating and 96.7% (29/30) of crabs were infected with metacercaria of paragonimus. Of all the study subjects, 11% (241/2172) of them were infected with the positive rate of 4.1% (89/270).</p><p><b>CONCLUSION</b>The incidence of paragonimiasis is closely related to dietetic habit in local residents. It is extremely necessary to increase the public awareness of paragonimiasis prevention and control and to improve the living conditions and dietetic habits.</p>

Significant decrease of recent thymic output function in patients with severe benzene intoxication / 中国实验血液学杂志

The aim of the present study was to investigate the level of T-cell receptor excision DNA circles (TREC) in peripheral blood mononuclear cells (PBMNC) of patients with severe benzene poison, thereby to evaluate the content of naive T cells and the recent thymic output function. Quantitative detection of TREC in DNA of PBMNCs from 16 normal individuals and 8 cases with severe benzene poison was preformed by real-time PCR using TaqMan technique. The results showed that TREC level was 6.69 +/- 4.79/1 000 PBMNCs in normal individuals, however, significant decrease was shown in patients with severe benzene poison (1.03 +/- 0.44/1 000 PBMNCs, P < 0.01). The TREC level was persistently low in period of benzene poisoning, even if peripheral blood cell counts were at normal levels. In conclusion, the recent thymic output function is remarkably decreased in patients with severe benzene intoxication, that may obviously damage the T cell immune function.

Evaluation of recent thymic output function in benzene-exposed workers / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To analyze the content of signal joint T-cell receptor excision DNA circles signal joint T-cell receptor excision DNA circles (sjTRECs) within peripheral blood mononuclear cells (PBMCs), thereby to infer the level of naive T cells and the recent thymic output function in benzene-exposed workers.</p><p><b>METHODS</b>Quantitative detection of sjTRECs in DNA of peripheral blood mononuclear cells from 11 normal individuals and 62 benzene-exposed workers were performed by real-time polymerase chain reaction (PCR) and TaqMan technique.</p><p><b>RESULTS</b>The median value of sjTRECs copies/1,000 PBMCs was 7.81 in normal individuals whereas it was 2.56 copies/1 000 PBMCs in age-unadjusted benzene-exposed workers (P < 0.01). And its levels were obviously different between two different age groups: that in 30-year-old group (1.76 copies/1,000 PBMCs, n = 23) was less than <or= 30-years-old group (3.19 copies/1,000 PBMCs, n = 39, P < 0.05).</p><p><b>CONCLUSIONS</b>Benzene exposure may influence the recent thymic output function, and the sjTRECs levels may relate with the age of benzene-exposed workers.</p>

Comparison of the clonal expansion of TCR Vbeta T cells in patients with acute promyelocytic leukemia in vivo and in vitro / 中国实验血液学杂志

In order to analyze the distribution and clonal expansion of TCR Vbeta subfamily T cells in patients with acute promyelocytic leukemia (APL) in vivo and in vitro after T cell culture, the peripheral blood mononuclear cells from 3 APL patients were expanded by rhIL-2 and anti-CD3 antibody using liquid T lymphocytes culture technique. The complementary determining region 3 (CDR3) of TCR beta with variable region genes was amplified in T cells from 3 APL cases before and after T cell culture by using RT-PCR. The positive products were further analyzed to identify the clonality of T cells by genescan. The results showed that only a part of 24 Vbeta subfamilies was detected in T cells from the patients, and some Vbeta subfamily T cells could be identified after T cells culture. The clonal expansion T cells in some TCR Vbeta subfamilies could be found in all patients. The similar oligoclonal expansion of Vbeta1, Vbeta3, Vbeta7, Vbeta16 and Vbeta20 T cells was detected in two cases at different time points after T cell culture. It is concluded that the restricted expression of TCR Vbeta subfamily in T cells from patients might be the common feature in leukemia. Some Vbeta subfamily T cells could be induced after T cells culture in vitro. The continual clonal expansion of TCR Vbeta subfamily T cells at different time points after T cells culture could be a specific immune response of patients T cells related to the specific APL cell associated antigen.

Estimate of Recent Thymic Output Function - Quantification of T Cell Receptor Rearrangement Excision Circles (TRECs) / 中国实验血液学杂志

For a long time, thymic function could not be monitored, as a consequence of the absence of adequate technology to detect recent thymic emigrants from naive T cells. T cell differentiation in the thymus is characterized by T cell receptor (TCR) rearrangement. During the rearrangement of TCRalpha gene segments, the deltaRec and psiJalpha rearrange to each other to delete the TCRdelta gene and form an extrachromosomal DNA circles, referred to as signal joint T cell receptor excision DNA circles (sjTRECs) or TRECs. TRECs are assumed to have a high stability, they can not multiply and consequently are diluted during T cell proliferation. It was recently suggested that quantitative detection of TRECs would allow for direct measurement of thymic output. In this review TRECs quantification is a powerful method to evaluate the thymic output function in both health and disease, including hematopoietic stem cell transplantation, hematopoietic malignancies, HIV infection and autoimmune disease, and so on is described.