Evidence for Inbreeding and Genetic Differentiation among Geographic Populations of the Saprophytic Mushroom Trogia venenata from Southwestern China

During the past 40 years, more than 400 Sudden Unexplained Deaths (SUDs) have occurred in Yunnan, southwestern China. Epidemiological and toxicological analyses suggested that a newly discovered mushroom called Trogia venenata was the leading culprit for SUDs. At present, relatively little is known about the genetics and natural history of this mushroom. In this study, we analyzed the sequence variation at four DNA fragments among 232 fruiting bodies of T. venenata collected from seven locations. Our ITS sequence analyses confirmed that all the isolates belonged to the same species. The widespread presence of sequence heterozygosity within many strains at each of three protein-coding genes suggested that the fruiting bodies were diploid, dikaryotic or heterokaryotic. Within individual geographic populations, we found significant deviations of genotype frequencies from Hardy-Weinberg expectations, with the overall observed heterozygosity lower than that expected under random mating, consistent with prevalent inbreeding within local populations. The geographic populations were overall genetically differentiated. Interestingly, while a positive correlation was found between population genetic distance and geographic distance, there was little correlation between genetic distance and barium concentration difference for the geographic populations. Our results suggest frequent inbreeding, geographic structuring, and limited gene flow among geographic populations of T. venenata from southwestern China.     

Multicenter evaluation of the performance and clinical utility in longitudinal monitoring of the Bayer Immuno 1 complexed PSA assay.

We conducted a multicenter evaluation of the analytical and clinical performance of the automated Bayer Immuno 1 complexed PSA (cPSA) assay, and compared assay performance to the Bayer Immuno 1 PSA assay. We sought to determine whether measurements of cPSA could be of clinical utility in the management of patients with prostate cancer. Results of the 10-day imprecision across three evaluation sites produced total CV < 2.50% and an analytical sensitivity of 0.02 microgram/L. There was an increased trend in clinical sensitivity for prostate cancer with increasing stage of disease (71-86%). Clinical specificity for patients with benign urogenital disease was 74.8%, and for other nonprostate diseases ranged from 91.1-100%. Retrospective serial monitoring of 155 patients with prostate cancer demonstrated concordance of cPSA measurements to clinical status for 97% of the patients analyzed. Results from the clinical studies using the Bayer Immuno 1 cPSA assay were comparable to results obtained with the Bayer Immuno 1 PSA assay. The Bayer Immuno 1 cPSA assay demonstrates analytical performance and clinical effectiveness in the management of prostate cancer patients during the course of disease and therapy.     

Three new species of the leafhopper genus Tambocerus Zhang & Webb (Hemiptera,Cicadellidae) from southern China

Three new species, Tambocerus dentatus, T. longicaudatus and T. robustispinus spp. n. from southern China, are described and illustrated. A checklist and distribution to the Tambocerus species from China is provided together with a key for their separation.     

玉米酯酶同工酶和过氧化物酶同工酶的分子量研究

本试验利用聚丙烯酰胺凝胶梯度电泳分步染色法直接对玉米苗期酯酶同工酶和过氧化物酶同工酶各酶带的分子量进行了比较测定。酯酶同工酶 E_1、E_2、E_3~F、E_3~S、a、b、c 各酶带的分子量分别为<20000,35200、33000、38500、29900、28500、34000道尔顿过氧化物酶同工酶 PX_4~F和 PX_4~S酶带的分子量分别为131000和149000道尔顿。根据酶带在均匀胶和梯度胶中的位置变化对各酶带的生化性质作了初步分析,发现 E_3~F和 E_3~S、PX_4~F 和 PX_4~S 在迁移率上的差异主要是分子量的差异。本文为同工酶的分子量测定提供了一个简便的方法。     

Formation of lymphocyte colonies under serum-free culture conditions in normal individuals and patients with chronic lymphocytic leukemia

This paper describes a culture system which supports the formation of B cell and some T cell colonies under serum-free conditions in peripheral blood samples of normal individuals and patients with chronic lymphocytic leukemia (CLL) of B cell type. In this system, serum is replaced by bovine serum albumin, transferrin, cholesterol, insulin and catalase or horseradish peroxidase. In addition, it is necessary to add staphylococcus protein A, mitomycin-treated T cells as feeders and phytohemagglutinin leukocyte-conditioned medium as a source of growth factors. The plating efficiency is greatly enhanced when normal cells are incubated with galactose oxidase prior to plating and when CLL cells are exposed sequentially to neuraminidase and galactose oxidase.     

The second stiffest axis of a beam-column: implications for cervical spine trauma

Based on an idealized model of a homogeneous, isotropic beam-column, the second stiffest axis under static loading was derived. The maximum allowable force for the second stiffest axis was then examined. The ratio of the maximum allowable forces of the second stiffest axis to the stiffest axis was established. The stiffness ratio of the second stiffest axis to the stiffest axis was also found. Taking buckling into consideration, the safe load region for all possible acting directions was derived. The implications of the idealized model for cervical spine trauma are discussed.