Conservation ecology of endangered species Paphiopedilum armeniacum (Orchidaceae)

Paphiopedilum armeniacum is an endangered orchid species, endemic to China. During the period of April 2000 to October 2005, 66 observation sites were selected in Luoshapo of Nushan Mountains in Yunnan, China, to carry out the conservation ecological research on P. armeniacum. A total of 443 genets (1302 ramets in total) of P. armeniacum were sampled, their biological characteristics such as reproductive pattern, phenology, and life cycle were observed, and the ecological habits of the species such as the habitat and the structure of communities were studied. Experiments on ex-situ conservation were conducted, and the cloned ramets were replanted to their original habitat after ex-situ reproduction in Shenzhen, Guangdong, China. The relationships between P. armeniacum and climate, vegetation, other environmental factors in the original habitat, and the biological characteristics of asexual offsprings of P. armeniacum, which were replanted to the original habitat after ex-situ cultivation and reproduction, were investigated. The studies show that P. armeniacum in Luoshapo grows very well in secondary shrub boskets or in tussocks on limestone hills. It has both sexual and asexual reproduction. Asexual reproduction serves to complete the sexual reproduction and to extend the lifetime of genets, while it does not reduce sexual reproduction. There are two modes of asexual reproduction-by tillering or by producing rhizomes. The litter of shrub boskets or tussocks provides P. armeniacum with humus, and the rhizome reproduction of P. armeniacum is an adaptation to the litter-covered condition, i.e. to escape from the unfavorable environment. Blooming rate of ramets is 7.39% 1.02%, and fruit set rate from the blooming ramets is 32.23% 12.08%. P. armeniacum is able to invade the moderately destroyed forests and those in early restoring but is unable to grow in large dense forests. P. armeniacum also grows very well in artificial spare woods in Shenzhen and can reproduce many cloned ramets, which can normally bloom and yield fruits after being replanted to the original habitat. The results of this study show that P. armeniacum can be conserved by ex-situ conservation and by replanting the ex-situ reproduced ramets to original habitat. On the basis of the analysis of endangered mechanisms of P. armeniacum, it can be concluded that P. armeniacum has strong capability of both asexual and sexual reproductions, and an emergency mechanism consisted of massive production of rhizomes to cope with damage. Because highly effective pollinating insects that facilitate pollination in P. armeniacum are present in the habitat, flowering ramets produce fruits with large quantity of seeds, many of which in turn grow into new genets that can reproduce many cloned ramets. P. armeniacum makes very effective use of its environment and has distinct characteristics of enduring harsh environmental conditions; therefore, rather than its own inherent biological defects, the main threats facing this species are the destruction of its survival space and the wipe-out collecting of the plants as a result of trading. Based on the analysis mentioned above, certain appropriate strategies have been proposed for the conservation of P. armeniacum.     

Microcella flavibacter sp. nov., isolated from marine sediment,and reclassification of Chryseoglobus frigidaquae,Chryseoglobus indicus,and Yonghaparkia alkaliphila as Microcella frigidaquae comb. nov., Microcella indica nom. nov., and Microcella alkalica nom. nov.

A novel Gram-staining positive, aerobic, rod-shaped, non-motile and yellow-pigmented actinobacterium, designated strain WY83^T, was isolated from a marine sediment of Indian Ocean. Strain WY83^T grew optimally at 30–35 °C, pH 7–8 and with 0–3% (w/v) NaCl. The predominant menaquinones were MK-10, MK-11 and MK-12, and the major fatty acids were C_19:1 ω9c/C19:1 ω11c, anteiso-C_15:0, C_17:0 3OH, and iso-C_16:0. The polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol and one unidentified glycolipid. The cell-wall peptidoglycan contained lysine as a diamino acid. The DNA G?+?C content was 72.3 mol%. Phylogenetic analysis based on 16S rRNA gene sequences and ninety-two bacterial core genes indicated that strain WY83^T formed an evolutionary lineage with Chryseoglobus frigidaquae JCM 14730^T, Chryseoglobus indicus CTD02-10-2^T, Yonghaparkia alkaliphila JCM 15138^T, Microcella alkaliphila DSM 18851^T and Microcella putealis DSM 19627^T within the radiation enclosing members of the family Microbacteriaceae. All pairwise percentage of conserved proteins between strain WY83^T and the closely related phylogenetic neighbors were greater than 65%. The average nucleotide identity and in silico DNA–DNA hybridization values were both below the thresholds used for the delineation of a new species. On the basis of the evidence presented, strains WY83^T, Y. alkaliphila JCM 15138^T, C. frigidaquae JCM 14730^T, M. alkaliphila DSM 18851^T and M. putealis DSM 19627^T should belong to different species of the same genus. Strain WY83^T represents a novel species of the genus Microcella, for which the name Microcella flavibacter sp. nov. is proposed. The type strain is WY83^T (=?KCTC 39637^T?=?MCCC 1A07099^T). Furthermore, Chryseoglobus frigidaquae, Chryseoglobus indicus, and Yonghaparkia alkaliphila were reclassified as Microcella frigidaquae comb. nov., Microcella indica nom. nov., and Microcella alkalica nom. nov., respectively.

     

LncRNA H19 rs4929984 Variant is Associated with Coronary Artery Disease Susceptibility in Han Chinese Female Population

Biochemical Genetics - Long non-coding RNAs (lncRNAs) have been reported to play an important role in cardiovascular diseases. The present study aimed to investigate the levels of lncRNA H19 in...     

Soluble ACE2-mediated cell entry of SARS-CoV-2 via interaction with proteins related to the renin-angiotensin system

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Protective Effect of Piceatannol Against Cerebral Ischaemia–Reperfusion Injury Via Regulating Nrf2/HO-1 Pathway In Vivo and Vitro

Neurochemical Research - Piceatannol is a natural plant-derived compound with protective effects against cardiovascular diseases. However, its effect on cerebral ischaemia–reperfusion injury...     

WormFarm: a quantitative control and measurement device toward automated Caenorhabditis elegans aging analysis

Caenorhabditis elegans is a leading model organism for studying the basic mechanisms of aging. Progress has been limited, however, by the lack of an automated system for quantitative analysis of longevity and mean lifespan. To address this barrier, we developed ‘WormFarm’, an integrated microfluidic device for culturing nematodes. Cohorts of 30–50 animals are maintained throughout their lifespan in each of eight separate chambers on a single WormFarm polydimethylsiloxane chip. Design features allow for automated removal of progeny and efficient control of environmental conditions. In addition, we have developed computational algorithms for automated analysis of video footage to quantitate survival and other phenotypes, such as body size and motility. As proof‐of‐principle, we show here that WormFarm successfully recapitulates survival data obtained from a standard plate‐based assay for both RNAi‐mediated and dietary‐induced changes in lifespan. Further, using a fluorescent reporter in conjunction with WormFarm, we report an age‐associated decrease in fluorescent intensity of GFP in transgenic worms expressing GFP tagged with a mitochondrial import signal under the control of the myo‐3 promoter. This marker may therefore serve as a useful biomarker of biological age and aging rate.     

Antitumour effects of pentapeptide derived from donkey serum albumin both in vitro and in vivo

AimsAntitumour effects of pentapeptide (LH) derived from donkey serum albumin hydrolysates were tested against tumour cells both in vitro and in vivo. The mechanism of LH induced tumour cell apoptosis was investigated.Main methodsHuman promyelocytic leukaemia cells (HL 60) were cultured to observe inhibition in vitro. Two animal models, a solid tumour and a non-entity myeloid leukaemia tumour, were used to determine the effect of LH in vivo. The former, fifty BALB/c nude mice were transplanted with HL 60 cells. The tumours were isolated completely and weighed after treatment. The latter, fifty BALB/c mice were injected intravenously with transplantable erythroblastic leukaemia cells (EL9611 cells). The survival time of mice was recorded and organs were used for histological study. The mechanism about tumour cell apoptosis was evaluated using fluorescence-activated cell sorting and transmission electron microscope for morphological assays.Key findingsThe LH inhibited tumour cell proliferation and the inhibitions were dependent on both the concentration and the dose; the best inhibition rate was up to 70% of the untreated control in vitro.It markedly inhibited the growth of a transplanted tumour with HL 60 cells in an immune-deficient nude mouse model. LH was also able to prolong the survival time of leukaemia mice with transplanted EL9611 cells and prevent the infiltration of leukaemia cells to the main internal organs.SignificanceThe LH peptide is an excellent inhibitor of tumour cell growth. These data provide the experimental foundation to use the LH peptide as a candidate for antitumour drugs in the future.     

Structure-based design of HSPA5 inhibitors: From peptide to small molecule inhibitors

We identified nine small-molecule hit compounds of Heat shock 70 kDa protein 5 (HSPA5) from cascade in silico screening based on the binding modes of the tetrapeptides derived from the peptide substrate or inhibitors of Escherichia coli HSP70. Two compounds exhibit promising inhibition activities from cancer cell viability and tumor inhibition assays. The binding modes of the hit compounds provide a platform for development of selective small molecule inhibitors of HSPA5.     

Intra-Peritoneal Hyperthermia Combining α-Galactosylceramide in the Treatment of Ovarian Cancer

The purpose of this study was to investigate the anti-tumor effect and potential mechanisms of i.p. hyperthermia in combination with α-galactosylceramide (α-GalCer) for the treatment of ovarian cancer. In this study, immuno-competent tumor models were established using murine ovarian cancer cell lines and treated with i.p. hyperthermia combining α-GalCer. Th1/Th2 cytokine expression profiles in the serum, NK cell cytotoxicity and phagocytic activities of dendritic cells (DCs) were assayed. We also analyzed the number of CD8⁺/IFN-γ⁺ tumor specific cytotoxic T cells, as well as the tumor growth based on depletion of lymphocyte sub-population. Therapeutic effect on those ovarian tumors was monitored by a non-invasive luminescent imaging system. Intra-peritoneal hyperthermia induced significant pro-inflammatory cytokines expression, and sustained the response of NK and DCs induced by α-GalCer treatment. The combination treatment enhanced the cytotoxic T lymphocyte (CTL) immune response in two mouse ovarian cancer models. This novel treatment modality by combination of hyperthermia and glycolipid provides a pronounced anti-tumor immune response and better survival. In conclusion, intra-peritoneal hyperthermia enhanced the pro-inflammatory cytokine secretion and phagocytic activity of DCs stimulated by α-GalCer. The subsequent CTL immune response induced by α-GalCer was further strengthened by combining with i.p. hyperthermia. Both innate and adaptive immunities were involved and resulted in a superior therapeutic effect in treating the ovarian cancer.