大庆地区新生儿苯丙酮尿症苯丙氨酸筛查切值的研究

目的探讨大庆地区新生儿苯丙氨酸（phenylalanine,Phe）测定时新生儿苯丙酮尿症筛查切值。方法以大庆地区出生的新生儿为筛查对象,于出生后48~72h,充分哺乳后采取足跟血,应用定量酶法检测标本中苯丙氨酸含量。结果2004年1月至2005年12月两年期间共筛查20214例,确定大庆市新生儿苯丙酮尿症的筛查切值为2.60mg/dl。结论新生儿足跟血Phe切值的确定为大庆市新生儿苯丙酮尿症的筛查工作提供依据,早发现早治疗可避免患儿的智力障碍,对提高我国人口素质有着十分重要的意义。

Detection of microRNA expressions in tissues and exfoliative cells reveals the potential role of miR-203 in oral lichen planus

Oral lichen planus （OLP） is a chronic inflammatory disorder and premalignantlesion, of which the mechanisms are still obscure. In the present study, the expression levels of miR-96/182/183 cluster, miR-203, miR-375, and miR-769-5p in both tissues and exfoliative cells of OLP patients as well as healthy volunteers were detected, differentially expressed miRNAs were identified and their correlation with OLP was evaluated by a biplot method. Experimental results show that miR-203 is significantly up-regulated in patient lesion tissues in comparison to volunteer mucosa tissues. Moreover, the contra- dictory insignificant expression changes of miR-203 as well as miR-96/182/183 cluster in comparisons of exfoliative cell samples suggest that different cell compositions in OLP lesion have distinct miRNA regulation, which accords with the histological heterogeneity of OLP. Finally, biplot analyses indicate the expression of miR-203 and miR-96/182/183 cluster are positively correlated in patient lesions. These results provide miR-203 as a molecular indicator of heterogeneity of OLP, and also a potential diagnostic biomarker or therapeutic target that deserves further studies.

Oxalate contents of commonly used Chinese medicinal herbs

OBJECTIVE:To assess the total and soluble oxalate contents of commonly used Chinese medicinal herbs.METHODS:Twenty-two Chinese medicinal herbs were extracted in both acid and water prior to determination of total and soluble oxalate,respectively.Oxalate was assayed in herbal extracts using a well-established enzymatic procedure.RESULTS:Among the 22 medicinal herbs,there was significant variation in oxalate content;Houttuynia cordata contained the highest amount of soluble oxalate(2146 mg/100 g) and Selaginella doederleinii contained the lowest amount(71 mg/100g).CONCLUSION:The results indicated that different Chinese medicinal herbs,even from the same family,contain significantly different amounts of oxalate.In susceptible individuals,the use of medicinal herbs with the highest oxalate contents could increase risk of kidney stone formation.

High throughput monoclonal antibody generation by immunizing multiple antigens

Recognizing proteins via the production of highly specific monoclonal antibodies(mAbs)is crucial to identifying proteins for proteomic research.However,traditional mAb generation is time-consuming with low efficiency.In this study,we assessed the high throughput method of producing mAbs by immunizing mice with multiple antigens in order to obtain hybridomas against these multiple antigens in one cell fusion.We selected eight proteins that play important roles in human physiological or pathological processes.These proteins were mixed and simultaneously administered to one mouse.We observed the immunizing period for 10 d,and determined the effect of liquid medium and semi-solid medium in hybridoma generation.As a result,all eight immunogens induced antibodies in the immunized mouse in one cell fusion,we obtained hybridomas specific to all eight proteins by enzyme-linked immuno sorbent assay(ELISA)screening,hybridomas against five out of eight showed specific positive in Western-blotting assays.This indicates that we generated mAbs specific to eight proteins in one cell fusion,greatly increasing the efficiency of mAb generation.Furthermore,we observed that hybridomas selected from the liquid medium and semi-solid medium showed different reactivity to antigens.Our study established high-throughput and time-saving methods for production of mAbs.These results provide alternative approaches for increasing the efficacy of mAb generation.

Quality-control method for the determination of biological activity of engineered calcineurin subunit B

The aim of this study was to establish a quality-control method for calcineurin subunit B(CNB) biological activity determinations. CNB enhances the p-nitrophenylphosphate(p NPP) dephosphorylating activity of calcineurin subunit A Δ316 mutant(CNAΔ316). A series of CNB concentrations were fitted to a four-parameter equation to calculate the corresponding p NPP maximum dephosphorylation rates. Values were calculated based on biological activity references using a parallel line method. The method was then validated for accuracy, precision, linearity, linear range, sensitivity, specificity, and robustness. The recovery results were greater than 98%. Intra-plate precision was 6.7%, with inter-plate precision of 10.8%. The coefficient of determination was greater than 0.98. The linear range was 0.05–50 μg m L?1, with sensitivity of 50 μg m L?1. Tested cytokines did not induce CNAΔ316 dephosphorylation of p NPP. The chosen CNAΔ316 concentration range did not affect activity determinations.