Prostaglandin E2 production by rat peritoneal macrophages: role of cellular and humoral factors in vivo in transfusion-associated immunosuppression

Abstract The transfusion of blood is associated with long-term immunosuppression, which has been postulated to influence immunosurveillance and cancer cell killing. The mononuclear phagocyte synthesises large quantities of PGE₂, and PGE₂ has been shown to inhibit the activity of a range of immunocompetent cell types. The role of mononuclear phagocyte PGE₂ synthesis in transfusion-associated immunosuppression, and the elements of transfused blood which control this immunosuppression, were investigated using a transfused rat model. A significant increase in macrophage PGE₂ synthesis was detected 7 days after transfusion with blood and serum. The storage of blood for 24 h increased the stimulatory activity of transfused blood. The effects of storage and serum on macrophage PGE₂ synthesis were greater than effects due to genetic differences between blood donor and recipient, and the serum effects indicated that a major factor activating PGE₂-mediated immunosuppression in transfused subjects may be humoral in nature.     

Identification of a missense phenylketonuria mutation at codon 408 in Chinese

Summary A single base transition of G to A at codon 408 of the phenylalanine hydroxylase gene is identified. This missense mutation results in the substitution of Arg⁴⁰⁸ for Gln⁴⁰⁸ (R408Q) and accounts for about 5% of phenylketonuria (PKU) chromosomes among Chinese. This mutation is in linkage disequilibrium with restriction fragment length polymorphism haplotype 4. In addition, another mutation (R408W), at the same codon and prevalent on haplotype 2 PKU chromosomes in Caucasians, is identified in a PKU allele of haplotype 41. Previously, this mutation has been observed on a haplotype 44 background in Chinese PKU patients.     

Hybridization of Two Major Termite Invaders as a Consequence of Human Activity

While hybridization of an invasive species with a native species is a common occurrence, hybridization between two invasive species is rare. Formosan subterranean termites (Coptotermes formosanus) and Asian subterranean termites (C. gestroi) are both ecologically successful and are the two most economically important termite pests in the world. Both species have spread throughout many areas of the world due to human activity; however, their distributions overlap in only three narrow areas because of distinct ecological requirements. In south Florida, where C. formosanus and C. gestroi are both invasive, the dispersal flight seasons of both species overlapped for the first time on record in 2013 and 2014. Pairings of heterospecific individuals were readily observed in the field and C. gestroi males preferentially engaged in mating behavior with C. formosanus females rather than females from their own species. In the laboratory, heterospecific and conspecific pairings had an equal colony establishment rate, but heterospecific incipient colonies had twice the growth rate of conspecific incipient colonies, suggesting a potential case of hybrid vigor. As all pre-zygotic barriers were lifted between the two species in the field, the apparent absence of post-zygotic barriers in the laboratory raises the possibility for introgressive hybridization in south Florida. While laboratory observations remain to be confirmed in the field, and the alate hybrid fertility is currently unknown, our results raise a tangible concern about the hybridization of two major destructive pest species. Such hybridization would likely be associated with a new economic impact.     

Assessment of the Polychlorinated Biphenyl (PCB) Occurrence in Copper Sulfates and the Influential Role of PCB Levels on Grapes

Copper sulfates (CuSO₄) are widely used as the primary component of fungicides in the grape industry. The agricultural-grade CuSO₄ that we collected from Chinese nationwide markets were found to be contaminated by polychlorinated dibenzo-p-dioxins and dibenzofurans and high levels of polychlorinated biphenyls (Σ₁₉PCBs: 0.32~9.51 ng/g). In the following research, we studied the impact of CuSO₄ application on PCB levels in grape products through a field experiment, and conducted a national survey to speculate the role that CuSO₄ played on the occurrence of PCB in grapes. In the field experiment, an obvious increase of PCBs in grape leaves (from 174 to 250 pg/g fw) was observed after Bordeaux mixture (the main component of which is CuSO₄) application. As to the main PCB congener in CuSO₄, the most toxic CB 126 (toxic equivalency factor = 0.1) also increased in grape peels (from 1.66 to 2.93 pg/g fw) after pesticide spray. Both the correlation study and the principal component analysis indicated that environmental factors were dominant PCB contributors to grapes, and grapes from e-waste dismantling area containing the highest PCBs also proved the notion. It is worth noting that this report describes the first research examining PCBs in CuSO₄ and its influence on agricultural products to date.     

Progressive Kidney Degeneration in Mice Lacking Tensin

Tensin is a focal adhesion phosphoprotein that binds to F-actin and contains a functional Src homology 2 domain. To explore the biological functions of tensin, we cloned the mouse tensin gene, determined its program of expression, and used gene targeting to generate mice lacking tensin. Even though tensin is expressed in many different tissues during embryogenesis, tensin null mice developed normally and appeared healthy postnatally for at least several months. Over time, −/− mice became frail because of abnormalities in their kidneys, an organ that expresses high levels of tensin. Mice with overt signs of weakness exhibited signs of renal failure and possessed multiple large cysts in the proximal kidney tubules, but even in tensin null mice with normal blood analysis, cysts were prevalent. Ultrastructurally, noncystic areas showed typical cell– matrix junctions that readily labeled with antibodies against other focal adhesion molecules. In abnormal regions, cell–matrix junctions were disrupted and tubule cells lacked polarity. Taken together, our data imply that, in the kidney, loss of tensin leads to a weakening, rather than a severing, of focal adhesion. All other tissues appeared normal, suggesting that, in most cases, tensin's diverse functions are redundant and may be compensated for by other focal adhesion proteins.     

Molecular phylogeny of five species of Dremomys (Rodentia: Sciuridae), inferred from cytochrome b gene sequences

Analyses of the mitochondrial cytochrome b gene (1140 bp) showed that Dremomys lokriah , D. pernyi , D. pyrrhomerus , D. rufigenis and D. gularis all are separate species. Dremomys pyrrhomerus showed 8.5% sequence variation from D. rufigenis, and the level of estimated sequence divergence observed among D. gularis , D. lokriah and D. pernyi was > 11%. With Tamiops and Callosciurus as the outgroup taxa, in both maximum likelihood and Bayesian analyses, the five Dremomys species formed one strongly supported monophyletic group and D. pyrrhomerus is closely related to D. rufigenis . The derived divergence times and fossil record suggested that the present geographical distributions of Dremomys owe much to the uplifting of the Himalayas and the successive glacial and interglacial in the Pliocene–Pleistocene.     

Palynological indications of environmental changes during the Late Cretaceous–Eocene on the southern continental margin of Laurasia, Xizang (Tibet)

A palynostratigraphic and palynofacies study of a geological section at Cuojiangding in Zhongba County has provided a basis for discussing the palaeoenvironmental evolution of the southern continental margin of Laurasia in Xizang (Tibet) towards the end of the Cretaceous Period and during the Paleogene. It is the only record of fossil spores and pollen grains from collision- and convergence-related sediments close to the major Yarlung Zangbo Suture. Deposits of the Padana Formation at the base of the section through the Qubeiya, Quxia, and Jialazi formations to the Rujiao Zangbo Conglomerate at the top are considered to range in age from Santonian to Eocene or possibly Oligocene. During this period the India plate collided with, and continued to push against, Laurasia plate. Two spore and pollen zones and three palynofacies types are recognized. These are correlated with two transgressive–regressive cycles associated with the collision, periods of geologically rapid uplift being reflected by the molasse-like sediments of the upper Quxia Formation and the Rujiao Zangbo Conglomerate, which accumulated during the Late Paleocene and Eocene–Oligocene respectively. The first regression led to intermittent subaerial exposure and erosion of the Cuojiangding area. The second ended the marine history of the area and led first to the development of swamps in a subtropical climate, now preserved in the coal-bearing Qiuwu Formation, and later to the development of mountainous terrain, with a cooler climate at higher elevations.     

Evidence for the signaling role of methyl jasmonate, methyl salicylate and benzothiazole between poplar (Populus simonii × P. pyramidalis ‘Opera 8277’) cuttings

Interplant communication has been widely demonstrated in plants, especially in herbaceous plants. In this study, mechanical damage was shown to affect the levels of pyrochatechol, chlorogenic acid, gallic acid and p-hydroxyl benzoic acid in poplar (Populus simonii × P. pyramidalis ‘Opera 8277’) cuttings, indicating the activation of defense response. In neighboring intact cuttings, the levels of those phenolics also varied when compared to the control, suggesting the interplant communication between poplar cuttings. Three volatiles, methyl jasmonate, methyl salicylate and benzothiazole, were detected in volatiles emitted from mechanically damaged poplar cuttings. All of them can induce changes in the levels of four phenolics. Therefore, they could act as airborne signals between P. simonii × P. pyramidalis ‘Opera 8277’ cuttings. The different change patterns of phenolic contents induced by different volatiles imply that the defense response activated in neighboring plants may be regulated by multiple signaling pathways. The results also suggest that the entire defense response of plants involves a variety of airborne signals in wound-induced volatiles.     

Joint analysis of longitudinal data and recurrent episodes data with application to medical cost analysis

This paper discusses regression analysis of longitudinal data in which the observation process may be related to the longitudinal process of interest. Such data have recently attracted a great deal of attention and some methods have been developed. However, most of those methods treat the observation process as a recurrent event process, which assumes that one observation can immediately follow another. Sometimes, this is not the case, as there may be some delay or observation duration. Such a process is often referred to as a recurrent episode process. One example is the medical cost related to hospitalization, where each hospitalization serves as a single observation. For the problem, we present a joint analysis approach for regression analysis of both longitudinal and observation processes and a simulation study is conducted that assesses the finite sample performance of the approach. The asymptotic properties of the proposed estimates are also given and the method is applied to the medical cost data that motivated this study.