Population structure and distribution patterns of the rare and endangered Ardisia violacea (Myrsinaceae)

Ardisia violacea (Myrsinaceae), one of China’s rare and endangered species, occurs only in Zhejiang and Taiwan provinces. We examined the population dynamics of this species to reveal details related to the development of populations. Assembling intensity indices were used, such as V/m, K, m^*, PAI, CA and I. Age class structure and the time-specific life tables were analyzed by the contiguous grid quadrate method. The population structures and distribution patterns of A. violacea in different habitats, age classes and quadrat scales are discussed and the life parameters such as the survival curve, mortality curve and life expectancy were estimated. The results show the age class distribution of the entire population generally fits a reverse “J” type curve, suggesting a growing population. The population spatial distribution pattern was clumped in all three habitats, especially in the age classes I–III, and had a uniform distribution in the age classes VII and IX. The plants mainly occurred at microsites with generally adequate light, water, nutrients and air. Micro-environmental factors and human factors can also have a great impact. In the age class structure pattern, the individual percentage of the first three age classes accounted for 71.19% in H1 (habitat 1), 68.18% in H2 (habitat 2) and 88.24% in H3 (habitat 3), which indicated the number of individuals in the first three age classes were larger than any other age classes. The population size peaked in the age classes III and X and only 13.1% individuals survive age class III to enter class IV. As a result, fewer middle and advanced aged individuals were found. Age class IV had the highest life expectancy for A. violacea. The survival curve approached to Deevy-II. The spatial distribution pattern of A. violacea populations was decided mainly by the interaction of biological and ecological characteristics of its environment, habitat heterogeneities, microenvironments and human disturbance.     

Antiosteoporotic flavonoids from Podocarpium podocarpum

A novel bi-isoflavonoid, podocarnone (1), together with five known flavonoids, namely genistein (2), afzelin (3), astragalin (4), luteolin (5) and pratensein (6), were isolated from the whole plants of Podocarpium podocarpum (DC.) Yang and Huang for the first time. The structure of podocarnone (1) was elucidated by detailed spectroscopic analyses, including 1D and 2D NMR techniques. All the isolated compounds were evaluated for their proliferative effects on osteoblasts derived from neonatal rat calvaria and inhibitory effects on multinucleated osteoclasts from rat marrow cells so as to explore the antiosteoporotic activity of these components. Podocarnone (1) exhibited potent stimulatory effects on osteoblastic proliferation and ALP (alkaline phosphatase) activity, and significantly inhibited the activity of osteoclastic TRAP (tartrate-resistant acid phosphatase) in the low concentration range of 10^?12–10^?14 mol/L, which were equivalent to the activity of genistein (2) in the concentration range of 10^?7–10^?9 mol/L. The other five known flavonoids also showed varied degrees of antiosteoporotic activities, and structure–activity relationship analysis revealed the number of phenolic rings contained in these structures maybe responsible for the antiosteoporosis property.     

Panamonon A and B,a pair of novel tetrahydrobenzofuran derivatives from Litsea panamonja (Nees) Hook. f.

A pair of novel tetrahydrobenzofuran derivatives with a unique C₁₈ carbon skeleton, panamonon A (1) and B (2), was isolated from the leaves and twigs of Litsea panamonja (Nees) Hook. f. These new compounds contain an unprecedented C₁₈ carbon skeleton consisting of a characteristic tetrahydrobenzofuran-2,5(3H,6H)-dione core with a biosynthetically extended geranyl side chain, designated as “panamonane”.

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Highlights? A pair of novel tetrahydrobenzofuran derivatives with a unique C₁₈ carbon skeleton was isolated. ? The new compounds possess an unprecedented C₁₈ carbon skeleton and are designated as “panamonane”. ? They are featured with a tetrahydrobenzofuran-2,5(3H,6H)-dione moiety and a geranyl side chain. ? The plausible biosynthetic pathways of them were discussed.     

Phenylpropanoid constituents from the seeds of Lithocarpus pachylepis

Five phenylpropanoids including one new compound balanophonin A (1), one new natural compound balanophonin B (2) were isolated from the seeds of Lithocarpus pachylepis for the first time. Their structures were elucidated by various spectroscopic techniques (UV, IR, MS, CD, 1D and 2D NMR). All compounds were evaluated for their anti-inflammatory activities on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW 264.7.     

Tangshenosides from Codonopsis lanceolata roots

A new symmetrical phenylpropanoid glycoside, tangshenoside VIII (1), together with six known tangshenosides (2–7) were isolated from the roots of Codonopsis lanceolata (Campanulaceae). Their structures were established on the basis of spectroscopic data, including two-dimensional NMR analyses. Tangshenosides have chemotaxonomic significance.     

Triterpenoid saponins from Eryngium yuccifolium ‘Kershaw Blue’

Phytochemical investigation on the root of Eryngium yuccifolium ‘Kershaw Blue’ resulted in the isolation and identification of two new polyhydroxyoleanene saponins, named eryngioside M and eryngioside N, together with 15 known triterpenoid saponins eryngiosides A-L, 21β-angeloyloxy-3β-[β-d-glucopyranosyl-(1 → 2)]-[β-d-xylopyranosyl-(1 → 3)]-β-d-glucuronopyranosyloxyolean-12-ene-15α,16α,22α,28-tetrol, saniculasaponin III, and saniculasaponin II. Their structures were established by extensive spectroscopic and chemical analyses. Eryngioside M and saniculasaponin II showed week cytotoxicity against human non-small cell lung tumor cells (A549) with GI₅₀ values of 37.5 ± 1.59 μM and 35.5 ± 1.11 μM, respectively.     

Interspecific Interactions between Phragmites australis and Spartina alterniflora along a Tidal Gradient in the Dongtan Wetland,Eastern China

The invasive species Spartina alterniora Loisel was introduced to the eastern coast of China in the 1970s and 1980s for the purposes of land reclamation and the prevention of soil erosion. The resulting interspecific competition had an important influence on the distribution of native vegetation, which makes studying the patterns and mechanisms of the interactions between Spartina alterniora Loisel and the native species Phragmites australis (Cav.) Trin ex Steud in this region very important. There have been some researches on the interspecific interactions between P. australis and S. alterniora in the Dongtan wetland of Chongming, east China, most of which has focused on the comparison of their physiological characteristics. In this paper, we conducted a neighbor removal experiment along a tidal gradient to evaluate the relative competitive abilities of the two species by calculating their relative neighbor effect (RNE) index. We also looked at the influence of environmental stress and disturbance on the competitive abilities of the two species by comparing interaction strength (I) among different tidal zones both for P. australis and S. alterniora. Finally, we measured physiological characteristics of the two species to assess the physiological mechanisms behind their different competitive abilities. Both negative and positive interactions were found between P. australis and S. alterniora along the environmental gradient. When the direction of the competitive intensity index for P. australis and S. alterniora was consistent, the competitive or facilitative effect of S. alterniora on P. australis was stronger than that of P. australis on S. alterniora. The interspecific interactions of P. australis and S. alterniora varied with environmental conditions, as well as with the method used, to measure interspecific interactions.     

Discovery Analysis of TCGA Data Reveals Association between Germline Genotype and Survival in Ovarian Cancer Patients

Background

Ovarian cancer remains a significant public health burden, with the highest mortality rate of all the gynecological cancers. This is attributable to the late stage at which the majority of ovarian cancers are diagnosed, coupled with the low and variable response of advanced tumors to standard chemotherapies. To date, clinically useful predictors of treatment response remain lacking. Identifying the genetic determinants of ovarian cancer survival and treatment response is crucial to the development of prognostic biomarkers and personalized therapies that may improve outcomes for the late-stage patients who comprise the majority of cases.

Methods

To identify constitutional genetic variations contributing to ovarian cancer mortality, we systematically investigated associations between germline polymorphisms and ovarian cancer survival using data from The Cancer Genome Atlas Project (TCGA). Using stage-stratified Cox proportional hazards regression, we examined 650,000 SNP loci for association with survival. We additionally examined whether the association of significant SNPs with survival was modified by somatic alterations.

Results

Germline polymorphisms at rs4934282 (AGAP11/C10orf116) and rs1857623 (DNAH14) were associated with stage-adjusted survival ( = 1.12e-07 and 1.80e-07, FDR  = 1.2e-04 and 2.4e-04, respectively). A third SNP, rs4869 (C10orf116), was additionally identified as significant in the exome sequencing data; it is in near-perfect LD with rs4934282. The associations with survival remained significant when somatic alterations.

Conclusions

Discovery analysis of TCGA data reveals germline genetic variations that may play a role in ovarian cancer survival even among late-stage cases. The significant loci are located near genes previously reported as having a possible relationship to platinum and taxol response. Because the variant alleles at the significant loci are common (frequencies for rs4934282 A/C alleles = 0.54/0.46, respectively; rs1857623 A/G alleles = 0.55/0.45, respectively) and germline variants can be assayed noninvasively, our findings provide potential targets for further exploration as prognostic biomarkers and individualized therapies.     

Unfolded Protein Response and Activated Degradative Pathways Regulation in GNE Myopathy

Although intracellular beta amyloid (Aβ) accumulation is known as an early upstream event in the degenerative course of UDP-N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase (GNE) myopathy, the process by which Aβdeposits initiate various degradative pathways, and their relationship have not been fully clarified. We studied the possible secondary responses after amyloid beta precursor protein (AβPP) deposition including unfolded protein response (UPR), ubiquitin proteasome system (UPS) activation and its correlation with autophagy system. Eight GNE myopathy patients and five individuals with normal muscle morphology were included in this study. We performed immunofluorescence and immunoblotting to investigate the expression of AβPP, phosphorylated tau (p-tau) and endoplasmic reticulum molecular chaperones. Proteasome activities were measured by cleavage of fluorogenic substrates. The expression of proteasome subunits and linkers between proteasomal and autophagy systems were also evaluated by immunoblotting and relative quantitative real-time RT-PCR. Four molecular chaperones, glucose-regulated protein 94 (GRP94), glucose-regulated protein 78 (GRP78), calreticulin and calnexin and valosin containing protein (VCP) were highly expressed in GNE myopathy. 20S proteasome subunits, three main proteasome proteolytic activities, and the factors linking UPS and autophagy system were also increased. Our study suggests that AβPP deposition results in endoplasmic reticulum stress (ERS) and highly expressed VCP deliver unfolded proteins from endoplasmic reticulum to proteosomal system which is activated in endoplasmic reticulum associated degradation (ERAD) in GNE myopathy. Excessive ubiquitinated unfolded proteins are exported by proteins that connect UPS and autophagy to autophagy system, which is activated as an alternative pathway for degradation.