Lymphocyte senescence in COPD is associated with loss of glucocorticoid receptor expression by pro-inflammatory/cytotoxic lymphocytes

Background

Glucocorticoid (GC) resistance is a major barrier in COPD treatment. We have shown increased expression of the drug efflux pump, Pgp1 in cytotoxic/pro-inflammatory lymphocytes in COPD. Loss of lymphocyte co-stimulatory molecule CD28 (lymphocyte senescence) was associated with a further increase in their pro-inflammatory/cytotoxic potential and resistance to GC. We hypothesized that lymphocyte senescence and increased Pgp1 are also associated with down-regulation of the GC receptor (GCR).

Methods

Blood was collected from 10 COPD and 10 healthy aged-matched controls. Flow cytometry was applied to assess intracellular pro-inflammatory cytokines, CD28, Pgp1, GCR, steroid binding and relative cytoplasm/nuclear GCR by CD28+ and CD28null T, NKT-like cells. GCR localization was confirmed by fluorescent microscopy.

Results

COPD was associated with increased numbers of CD28nullCD8+ T and NKT-like cells. Loss of CD28 was associated with an increased percentage of T and NKT-like cells producing IFNγ or TNFα and associated with a loss of GCR and Dex-Fluor staining but unchanged Pgp1. There was a significant loss of GCR in CD8 + CD28null compared with CD8 + CD28+ T and NKT-like cells from both COPD and controls (eg, mean ± SEM 8 ± 3% GCR + CD8 + CD28null T-cells vs 49 ± 5% GCR + CD8 + CD28+ T-cells in COPD). There was a significant negative correlation between GCR expression and IFNγ and TNFα production by T and NKT-like cells(eg, COPD: T-cell IFNγ R = −.615; ) and with FEV1 in COPD (R = −.777).

Conclusions

COPD is associated with loss of GCR in senescent CD28null and NKT-like cells suggesting alternative treatment options to GC are required to inhibit these pro-inflammatory/cytotoxic cells.     

Effects of somatic mutations on CDR loop flexibility during affinity maturation

Prior studies suggest that antibody affinity maturation is achieved, in part, via prearranging the CDRs for binding. The implication is that the entropy cost of binding is reduced and that this rigidification occurs as a consequence of somatic mutations during maturation. However, how these mutations modulate CDR flexibility is unclear. Here, molecular dynamics simulations captured CDR flexibility differences between four mature antibodies (7G12, AZ28, 28B4, and 48G7) and their germline predecessors. Analysis of their trajectories: (1) rationalized how mutations during affinity maturation restrict CDR motility, (2) captured the equilibrium between bound and unbound conformations for the H3 loop of unliganded 7G12, and (3) predicted a set of new mutations that, according to our simulations, should diminish binding by increasing flexibility.     

Identification of novel allosteric modulators for the G-protein coupled US28 receptor of human cytomegalovirus

The highly constitutively active G-protein coupled receptor US28 of human cytomegalovirus (HCMV) is an interesting pharmacological target because of its implication on viral dissemination, cardiovascular diseases and tumorigenesis. We found that dihydroisoquinolinone and tetrahydroisoquinoline scaffolds may be promising lead structures for novel US28 allosteric inverse agonists. These scaffolds were rapidly synthesized by radical carboamination reactions followed by non-radical transformations. Our novel US28 allosteric modulators provide valuable scaffolds for further ligand optimization and may be helpful chemical tools to investigate molecular mechanisms of US28 constitutive signaling and its role in pathogenesis.     

黄颡单尾虫(粘体门,双壳目)的重描述及基于28S rDNA和ITS-5.8S序列的系统地位分析

采用形态分类学方法与以28S rDNA和ITS-5.8S序列为基础的分子系统学研究方法,对采自嘉陵江重庆市磁器口江段的黄颡单尾虫Unicauda pelteobagrusMa,1998进行了形态学和分子生物学的研究。基于28S rDNA数据探讨了黄颡单尾虫以及单尾虫属与相邻种属粘孢子虫间的系统地位;基于5.8S rDNA数据比较分析了粘孢子虫的系统地位。补充了黄颡单尾虫重庆种群形态学信息和28S rDNA、ITS-5.8S rDNA序列的分子信息。     

直突摇蚊亚科部分属28S rDNA D1序列的分子系统发育关系(双翅目,摇蚊科)

利用28S rDNA D1部分基因序列对直突摇蚊亚科代表性属级阶元进行了分子系统学研究。测定了12个内群属和2种外群的28SrDNAD1片段,并结合GenBank中3个同亚科种类该基因的同源序列进行了分析。采用2种建树方法(距离邻近法NJ和最大俭约法MP)分析了直突摇蚊亚科内属级分类单元的分子系统发育关系。结果表明,滨海摇蚊属Clunio位于系统发育树的基部,与该属营海洋生活的特殊性一致。心突摇蚊属和真开氏摇蚊属互为姐妹群,流环足摇蚊属和刀突摇蚊属互为姐妹群,此结果与基于形态学的系统发育研究相结果一致。其它属间的系统发育关系因尚无前人研究而有待做进一步研究。本研究同时证明28S rDNA D1基因片段在分析摇蚊科昆虫属级及属内阶元关系上具有一定的指导意义。     

Molecular phylogeny of Pholadoidea Lamarck, 1809 supports a single origin for xylotrophy (wood feeding) and xylotrophic bacterial endosymbiosis in Bivalvia

The ability to consume wood as food (xylotrophy) is unusual among animals. In terrestrial environments, termites and other xylotrophic insects are the principle wood consumers while in marine environments wood-boring bivalves fulfill this role. However, the evolutionary origin of wood feeding in bivalves has remained largely unexplored. Here we provide data indicating that xylotrophy has arisen just once in Bivalvia in a single wood-feeding bivalve lineage that subsequently diversified into distinct shallow- and deep-water branches, both of which have been broadly successful in colonizing the world’s oceans. These data also suggest that the appearance of this remarkable life habit was approximately coincident with the acquisition of bacterial endosymbionts. Here we generate a robust phylogeny for xylotrophic bivalves and related species based on sequences of small and large subunit nuclear rRNA genes. We then trace the distribution among the modern taxa of morphological characters and character states associated with xylotrophy and xylotrepesis (wood-boring) and use a parsimony-based method to infer their ancestral states. Based on these ancestral state reconstructions we propose a set of plausible hypotheses describing the evolution of symbiotic xylotrophy in Bivalvia. Within this context, we reinterpret one of the most remarkable progressions in bivalve evolution, the transformation of the “typical” myoid body plan to create a unique lineage of worm-like, tube-forming, wood-feeding clams. The well-supported phylogeny presented here is inconsistent with most taxonomic treatments for xylotrophic bivalves, indicating that the bivalve family Pholadidae and the subfamilies Teredininae and Bankiinae of the family Teredinidae are non-monophyletic, and that the principle traits used for their taxonomic diagnosis are phylogenetically misleading.     

Longidorus carniolensis sp. n. (Nematoda, Longidoridae) from vineyard soil in Slovenia

A new needle nematode, Longidorus carniolensissp. n., recovered from the soil around the roots of grapevine Vitis vinifera L. from Slovenia, is described and illustrated. Longidorus carniolensisis an amphimictic species, characterised by females with a moderately long (L=5.6-8.2 mm) and plump (a=51-72.4, ave. 66.3) body, assuming a spiral to C-shape when heat relaxed. Head region continuous, anteriorly almost flat, lip region 23-25 μm wide; guiding ring situated posteriorly (42-47 μm, 43-50 μm in males), odontostyle long (ave. 146.6 (136-157) μm); pharyngeal glands with normal location, their nuclei of approximately equal size; tail bluntly conoidal to almost hemispherical. Males abundant, spicules slender and long (122-145 μm), ventromedian supplements 13-17, irregularly spaced, preceded by an adanal pair. Four juvenile stages present, the first stage juvenile with bluntly conoidal tail. Codes for identifying the new species when using the key by Chen et al. (1997) are: A 56, B 4, C 4, D 1, E 4, F 35, G 1, H 1, I 2. The new species is morphologically the most similar to Longidorus poessneckensis Altherr, 1974, Longidorus macrosoma Hooper, 1961, Longidorus caespiticola Hooper, 1961, Longidorus helveticus Lamberti et al., 2001, Longidorus macroteromucronatus Altherr, 1974, Longidorus pius Barsi & Lamberti, 2001, Longidorus raskii Lamberti & Agostinelli, 1993, Longidorus kheirii Pedram et al. 2008, Longidorus silvae Roca, 1993, Longidorus iuglandis Roca et al., 1985, Longidorus vinearum Bravo & Roca, 1995 and Longidorus major Roca & d'Erico, 1987, but differs from these species either by the body and odontostyle length, position of guide ring, head region and tail shape or the shape of the first stage juvenile tail. Sequence data from the D2-D3 region of the 28S rDNA distinguishes this new species from other speciesof the genus Longidorus with known sequences. Relationships of Longidorus carniolensissp. n. with other Longidorus species based on analysis of this DNA fragment and morphology are discussed.     

Two nor-triterpene lactones from Caltha palustris

The chemical constituents present in the chloroform-soluble fraction of the ethanolic extract of Caltha palustris have been investigated. Two of these, caltholide and epicaltholide have been characterized as 24-nor-3β-hydroxylupan-13β,28-lactone and its 3α-isomer, respectively.