Clonal integration facilitates spread of Paspalum paspaloides from terrestrial to cadmium-contaminated aquatic habitats.

Cadmium (Cd) is a hazardous environmental pollutant with high toxicity to plants, which has been detected in many wetlands. Clonal integration (resource translocation) between connected ramets of clonal plants can increase their tolerance to stress. We hypothesised that clonal integration facilitates spread of amphibious clonal plants from terrestrial to Cd-contaminated aquatic habitats. The spread of an amphibious grass Paspalum paspaloides was simulated by growing basal older ramets in uncontaminated soil connected (allowing integration) or not connected (preventing integration) to apical younger ramets of the same fragments in Cd-contaminated water. Cd contamination of apical ramets of P. paspaloides markedly decreased growth and photosynthetic capacity of the apical ramets without connection to the basal ramets, but did not decrease these properties with connection. Cd contamination did not affect growth of the basal ramets without connection to the apical ramets, but Cd contamination of 4 and 12 mg·l-1 significantly increased growth with connection. Consequently, clonal integration increased growth of the apical ramets, basal ramets and whole clones when the apical ramets were grown in Cd-contaminated water of 4 and 12 mg·l-1 . Cd was detected in the basal ramets with connection to the apical ramets, suggesting Cd could be translocated due to clonal integration. Clonal integration, most likely through translocation of photosynthates, can support P. paspaloides to spread from terrestrial to Cd-contaminated aquatic habitats. Amphibious clonal plants with a high ability for clonal integration are particularly useful for re-vegetation of degraded aquatic habitats caused by Cd contamination.

First Report of Pestalotiopsis sydowiana Causing Leaf Necrosis of Myrica rubra in China.

Red bayberry (Myrica rubra Seib. & Zucc.) has great economic importance in eastern and southern China. However, increasing cultivation of red bayberry has resulted in an increase in diseases such as leaf necrosis. In April 2011, a survey was conducted to identify the causal agents of leaf necrosis of red bayberry (cv. Biqi) in Cixi City, Zhejiang Province. Symptoms began with oval and pale brown lesions (2 mm in diameter) that developed into a round to irregular shape (4 to 12 mm in diameter) with pale brown centers and dark brown borders. After approximately 4 months, necrotic lesions expanded to the leaf tips or margins. Black acervuli developed on lesions at later stages. Leaf tissues were surface sterilized with 0.5% sodium hypochlorite for 3 min and rinsed in sterile water before plating onto potato dextrose agar (PDA). Seven isolates were obtained from four samples from four fields on PDA at 25°C. The colonies were cottony white with filiform edges and produced a honey yellow color into the agar at 7 days. Conidia were produced in ink-like fruiting bodies at 4 days at 25°C on PDA. Conidia were straight or slightly curved, fusiform, and five celled with constrictions at the septa. Conidia ranged from 18.7 to 25.8 × 6.2 to 7.7 µm with hyaline apical and basal cells. Thirteen percent of the apical cells had two and the rest had three hyaline appendages ranging from 11.2 to 26.0 µm long. Basal appendages were hyaline, straight, and varied from 3.6 to 5.8 µm long. The color of three median cells was light to dark brown and demonstrated versicolorous. These morphological characteristics matched those of Pestalotiopsis sydowiana (Bresadola) Sutton (1). The morphological identification of the fungus was confirmed by nucleotide blast analysis of the 5.8S subunit and flanking internal transcribed spacers (ITS1 and ITS2) of rDNA regions (GenBank Accession No. JQ322999), which revealed 100% with those of other P. sydowiana isolates (e.g., GenBank Accession No. FJ478105). Koch's postulates were confirmed with 20 healthy leaves of the same size on three branches of three plants in the field. Leaves were wounded by pressing slightly with sterile needles. Mycelial plugs (5 mm in diameter) obtained from the periphery of 7-day-old cultures were placed onto the wounds and covered with sterile-water-saturated cotton. Wounded leaves treated with sterile agar plugs served as controls. The inoculated leaves were sealed in moist plastic bags for 24 h to establish high humid conditions at 21 to 30°C. After 23 days, symptoms on all inoculated leaves were identical to those described above, whereas noninoculated control leaves did not show any symptoms. The fungus was consistently reisolated from the lesions. To our knowledge, this is the first report of P. sydowiana causing leaf necrosis of M. rubra in China. Results can help to better understand the diseases threatening red bayberry trees and develop effective control strategies for better fruit production. Reference: (1) E. F. Guba. Monograph of Monochaetia and Pestalotia. Harvard University Press, Cambridge, MA, 1961.

The del(7q) subgroup in uterine leiomyomata: genetic and biologic characteristics. Further evidence for the secondary nature of cytogenetic abnormalities in the pathobiology of uterine leiomyomata.

Rearrangement of 7q represents one of the major cytogenetic subgroups in uterine leiomyomata, the most common tumors arising in females. Herein we report cytogenetic analysis on a series of 22 cases of uterine leiomyomata with 7q abnormalities, and describe observations regarding tumor size and maintenance of the tumor cells in culture. We discuss the frequent finding of mosaic tumors containing both cells with the 7q rearrangement and karyotypically normal cells. Clonality studies of three mosaic cases reveal nonrandom X chromosome inactivation substantiating prior findings suggesting the secondary nature of chromosome aberrations in these tumors. Genes mapped in 7q22 and those identified in the pathobiology of other uterine leiomyomata subgroups are discussed in addition to a perspective on the role of the 7q22 leiomyomata gene.

[Preliminary study of naturally occurring anti-idiotypic antibodies in schistosomiasis japonica].

In this study, naturally occurring anti-idiotypic antibodies in sera from patients with schistosomiasis japonica were demonstrated by using McAb (5B5H)-ELISA. McAb 5B5H against Schistosoma japonicum soluble egg antigen (SEA) was purified by precipitation with 50%, 40% and 33% saturated (NH4)2SO4 and coupled to CNBr-activated Sepharose 4B (Pharmacia). 5B5H column was loaded with sera from two patients with schistosomiasis japonica and then the bound material was eluated with 3M KCNS. The resulting eluate was further characterized with McAb-ELISA and complement fixation test in order to minimize the possible interference of circulating antigen-antibody complex. The results showed that the eluate contained mainly anti-Id antibodies. In the competitive 5B5H-ELISA tests, SEA markedly inhibited the interaction of 5B5H (Id) and anti-Id anti-bodies, suggesting that the relevant idiotype is within or adjacent closely to antigen binding site of anti-SEA molecule. The anti-Id antibodies were detected using 5B5H-ELISA in patients with schistosomiasis japonica from A and B areas, positive rate of 35.1% (13/37) and 60% (18/30) was obtained respectively. No cross or false reactions were found with sera from patients with fasciolopsiasis buski (0/15), clonorchiasis sinensis (0/15) and normal group of students (0/54) with the exception of one out of 20 patients with paragonimiasis westermani.