Diurnal temperature range as a key predictor of plants' elevation ranges globally

A prominent hypothesis in ecology is that larger species ranges are found in more variable climates because species develop broader environmental tolerances, predicting a positive range size-temperature variability relationship. However, this overlooks the extreme temperatures that variable climates impose on species, with upper or lower thermal limits more likely to be exceeded. Accordingly, we propose the 'temperature range squeeze' hypothesis, predicting a negative range size-temperature variability relationship. We test these contrasting predictions by relating 88,000 elevation range sizes of vascular plants in 44 mountains to short- and long-term temperature variation. Consistent with our hypothesis, we find that species' range size is negatively correlated with diurnal temperature range. Accurate predictions of short-term temperature variation will become increasingly important for extinction risk assessment in the future.

Antifungal mechanism of volatile compounds emitted by Actinomycetota Paenarthrobacter ureafaciens from a disease-suppressive soil on Saccharomyces cerevisiae

Increasing evidence suggests that in disease-suppressive soils, microbial volatile compounds (mVCs) released from bacteria may inhibit the growth of plant-pathogenic fungi. However, the antifungal activities and molecular responses of fungi to different mVCs remain largely undescribed. In this study, we first evaluated the responses of pathogenic fungi to treatment with mVCs from Paenarthrobacter ureafaciens. Then, we utilized the well-characterized fungal model organism Saccharomyces cerevisiae to study the potential mechanistic effects of the mVCs. Our data showed that exposure to P. ureafaciens mVCs leads to reduced growth of several pathogenic fungi, and in yeast cells, mVC exposure prompts the accumulation of reactive oxygen species. Further experiments with S. cerevisiae deletion mutants indicated that Slt2/Mpk1 and Hog1 MAPKs play major roles in the yeast response to P. ureafaciens mVCs. Transcriptomic analysis revealed that exposure to mVCs was associated with 1,030 differentially expressed genes (DEGs) in yeast. According to gene ontology and Kyoto Encyclopedia of Genes and Genomes analyses, many of these DEGs are involved in mitochondrial dysfunction, cell integrity, mitophagy, cellular metabolism, and iron uptake. Genes encoding antimicrobial proteins were also significantly altered in the yeast after exposure to mVCs. These findings suggest that oxidative damage and mitochondrial dysfunction are major contributors to the fungal toxicity of mVCs. Furthermore, our data showed that cell wall, antioxidant, and antimicrobial defenses are induced in yeast exposed to mVCs. Thus, our findings expand upon previous research by delineating the transcriptional responses of the fungal model. IMPORTANCE Since the use of bacteria-emitted volatile compounds in phytopathogen control is of considerable interest, it is important to understand the molecular mechanisms by which fungi may adapt to microbial volatile compounds (mVCs). Paenarthrobacter ureafaciens is an isolated bacterium from disease-suppressive soil that belongs to the Actinomycetota phylum. P. ureafaciens mVCs showed a potent antifungal effect on phytopathogens, which may contribute to disease suppression in soil. However, our knowledge about the antifungal mechanism of mVCs is limited. This study has proven that mVCs are toxic to fungi due to oxidative stress and mitochondrial dysfunction. To deal with mVC toxicity, antioxidants and physical defenses are required. Furthermore, iron uptake and CAP proteins are required for antimicrobial defense, which is necessary for fungi to deal with the thread from mVCs. This study provides essential foundational knowledge regarding the molecular responses of fungi to inhibitory mVCs.

GAD65 as a potential marker for cognitive performance in an adult population with prediabetes

BACKGROUND

Diabetes mellitus (DM) is a well-known risk factor for cognitive dysfunction in aged populations. However, there are inconsistent reports about impaired fasting glucose or prediabetes as an independent risk factor for cognitive function. Glutamic acid decarboxylase 65 (GAD65) is the key enzyme responsible for γ-aminobutyric acid synthesis in the central nervous system. Antibodies against GAD65 (GAD65Abs) are not only detected in approximately 80% of early-onset type 1 DM, but also linked to several neurological disorders.

AIM

This study aims to investigate the association between GAD65Ab titer levels and cognitive performance. In addition, we assessed the effect of GAD65Ab on cognitive function in adults with normal fasting glucose, prediabetes and DM.

METHODS

A total of 328 subjects aged 49.10 ± 5.72 years were enrolled from the Third Health and Nutrition Examination Survey dataset. Cognitive performance was assessed by three computerized neurobehavioral tests, including the serial digit learning test, simple reaction time test (SRTT) and symbol-digit substitution test (SDST).

RESULTS

Subjects with higher GAD65Ab titers had significantly poorer cognitive function in the SRTT and SDST (P < 0.05). Additionally, GAD65Ab was associated with cognitive decline in non-diabetic adults after adjusting for a number of relevant variables (P < 0.05 in both SRTT and SDST).

CONCLUSIONS

These results indicate that GAD65Ab may be a potential marker for cognitive impairment in non-diabetic adults.

Quantum thermodynamics from the nonequilibrium dynamics of open systems: Energy, heat capacity, and the third law

In a series of papers, we intend to take the perspective of open quantum systems and examine from their nonequilibrium dynamics the conditions when the physical quantities, their relations, and the laws of thermodynamics become well defined and viable for quantum many-body systems. We first describe how an open-system nonequilibrium dynamics (ONEq) approach is different from the closed combined system +  environment in a global thermal state (CGTs) setup. Only after the open system equilibrates will it be amenable to conventional thermodynamics descriptions, thus quantum thermodynamics (QTD) comes at the end rather than assumed in the beginning. The linkage between the two comes from the reduced density matrix of ONEq in that stage having the same form as that of the system in the CGTs. We see the open-system approach having the advantage of dealing with nonequilibrium processes as many experiments in the near future will call for. Because it spells out the conditions of QTD's existence, it can also aid us in addressing the basic issues in quantum thermodynamics from first principles in a systematic way. We then study one broad class of open quantum systems where the full nonequilibrium dynamics can be solved exactly, that of the quantum Brownian motion of N strongly coupled harmonic oscillators, interacting strongly with a scalar-field environment. In this paper, we focus on the internal energy, heat capacity, and the third law. We show for this class of physical models, amongst other findings, the extensive property of the internal energy, the positivity of the heat capacity, and the validity of the third law from the perspective of the behavior of the heat capacity toward zero temperature. These conclusions obtained from exact solutions and quantitative analysis clearly disprove claims of negative specific heat in such systems and dispel allegations that in such systems the validity of the third law of thermodynamics relies on quantum entanglement. They are conceptually and factually unrelated issues. Entropy and entanglement will be the main theme of our second paper on this subject matter.

Eudesmin attenuates Helicobacter pylori-induced epithelial autophagy and apoptosis and leads to eradication of H. pylori infection

Eudesmin has been proven to possess anti-inflammatory effects. In the present study, the effects of eudesmin on Helicobacter pylori (H. pylori)-mediated autophagy, apoptosis, immune response and inflammation were determined in human gastric adenocarcinoma (AGS) cells in vitro and in C57BL/6 mice in vivo. Detection of the production of interleukin (IL)-8, IL-1β and immunoglobulin M (IgM) was performed using ELISA. Identification of the activation of apoptosis-associated caspase-3, -8 and -9 proteins, Bcl-2-associated X protein (Bax) and BH3 interacting domain death agonist (Bid) protein, was determined through western blot analysis. Autophagy microtubule-associated protein 1A/1B-light chain 3, isoform B (LC-3B) expression was measured using immunostaining. The results of the present study demonstrated that eudesmin inhibited the growth of H. pylori, with increased inhibition activity against antibiotic resistant strains compared with the reference strain. In addition, H. pylori-induced IL-8 secretion, LC-3B expression and apoptosis-associated protein (caspase-3, -8 and -9, Bax and Bid) activation in AGS cells was suppressed by eudesmin. Furthermore, eudesmin suppressed IL-1β and IgM production in H. pylori-infected C57BL/6 mice in vivo. In conclusion, eudesmin may be developed as a promising therapeutic agent to prevent and/or treat H. pylori-associated gastric inflammation.

Anti-Proliferative Activity of Triterpenoids and Sterols Isolated from Alstonia scholaris against Non-Small-Cell Lung Carcinoma Cells

(1) Background: In China and South Asia, Alstonia scholaris (Apocynaceae) is an important medicinal plant that has been historically used in traditional ethnopharmacy to treat infectious diseases. Although various pharmacological activities have been reported, the anti-lung cancer components of A. scholaris have not yet been identified. The objective of this study is to evaluate the active components of the leaf extract of A. scholaris, and assess the anti-proliferation effects of isolated compounds against non-small-cell lung carcinoma cells; (2) Methods: NMR was used to identify the chemical constitutes isolated from the leaf extract of A. scholaris. The anti-proliferative activity of compounds against non-small-cell lung carcinoma cells was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay; (3) Results: Eight triterpenoids and five sterols were isolated from the hexane portion of A. scholaris, and structurally identified as: (1) ursolic acid, (2) oleanolic acid, (3) betulinic acid, (4) betulin, (5) 2β,3β,28-lup-20(29)-ene-triol, (6) lupeol, (7) β-amyrin, (8) α-amyrin, (9) poriferasterol, (10) epicampesterol, (11) β-sitosterol, (12) 6β-hydroxy-4-stigmasten-3-one, and (13) ergosta-7,22-diene-3β,5α,6β-triol. Compound 5 was isolated from a plant source for the first time. In addition, compounds 9, 10, 12, and 13 were also isolated from A. scholaris for the first time. Ursolic acid, betulinic acid, betulin, and 2β,3β,28-lup-20(29)-ene-triol showed anti-proliferative activity against NSCLC, with IC50 of 39.8, 40.1, 240.5 and 172.6 μM, respectively.; (4) Conclusion: These findings reflect that pentacyclic triterpenoids are the anti-lung cancer chemicals in A. scholaris. The ability of ursolic acid, betulinic acid, betulin, and 2β,3β,28-lup-20(29)-ene-triol to inhibit the proliferative activity of NSCLC can constitute a valuable group of therapeutic agents in the future.

Fatsia polycarpa Triterpenoids and Acetylated Derivatives Thereof Inhibit Tumor Necrosis Factor-α-Induced Inflammation

Fatsia polycarpa Hayata is an evergreen shrub endemic to Taiwan and used locally to treat several inflammatory disorders. The crude extract of F. polycarpa has been proven to exhibit an anti-inflammatory effect in vitro and in vivo; however, which constituents of the extract confer the anti-inflammatory function remains unclear. Fatsicarpain D (Fat D) and fatsicarpain F (Fat F) are oleanane-type triterpenoids and two of the feature constituents of the F polycarpa extract. Ester substitution on C-3 has been proposed to enhance the activities of triterpenoids. Thus, this study compared and characterized the anti-inflammatory activities of Fat D, Fat F, and the C-3-acetylated derivatives thereof. These compounds were toxic to RAW 264.7 cells, but not to FL83B cells. The compounds dose-dependently inhibited tumor necrosis factor-α (TNF-α)-induced expression of inducible nitric oxide synthase in FL83B cells, with the IC50 values being Fat D 8.5 μM, acetylated Fat D 10.4 μM, acetylated Fat F 10.7 μM, and Fat F 27.4 μM, respectively. Thus, acetylation of C-3 improved the activity of Fat F. Moreover, the compounds suppressed TNF-α-induced expression of nuclear factor-κB (NF-κB) p65 subunit and protein tyrosine phosphatase-1B. Furthermore, they inhibited TNF-α-mediated activation of the inhibitor kappa B kinase (IKK), and that of the mitogen-activated protein kinases (MAPKs) extracellular-signal-regulated kinase (ERK), and c-Jun N-terminal kinase (JNK), but promoted the activation of MAPK p38, which was found to be anti-inflammatory in certain cell types. Thus, Fat D and Fat F exhibited obvious anti-inflammatory activities in vitro and inhibited ERK, JNK, and the IKK/NF-κB pathway.

The Pleiotropic Antibacterial Mechanisms of Ursolic Acid against Methicillin-Resistant Staphylococcus aureus (MRSA)

(1) BACKGROUND: Several triterpenoids were found to act synergistically with classes of antibiotic, indicating that plant-derived chemicals have potential to be used as therapeutics to enhance the activity of antibiotics against multidrug-resistant pathogens. However, the mode of action of triterpenoids against bacterial pathogens remains unclear. The objective of this study is to evaluate the interaction between ursolic acid against methicillin-resistant Staphylococcus aureus (MRSA); (2) METHODS: The ability of ursolic acid to damage mammalian and bacterial membranes was examined. The proteomic response of methicillin-resistant S. aureus in ursolic acid treatment was investigated using two-dimensional (2D) proteomic analysis; (3) RESULTS: Ursolic acid caused the loss of staphylococcal membrane integrity without hemolytic activity. The comparison of the protein pattern of ursolic acid-treated and normal MRSA cells revealed that ursolic acid affected a variety of proteins involved in the translation process with translational accuracy, ribonuclease and chaperon subunits, glycolysis and oxidative responses; (4) CONCLUSION: The mode of action of ursolic acid appears to be the influence on the integrity of the bacterial membrane initially, followed by inhibition of protein synthesis and the metabolic pathway. These findings reflect that the pleiotropic effects of ursolic acid against MRSA make it a promising antibacterial agent in pharmaceutical research.

Characterization of Genomic Inheritance of Intergeneric Hybrids between Ascocenda and Phalaenopsis Cultivars by GISH, PCR-RFLP and RFLP

Background

The intergeneric hybrids between Ascocenda John De Biase ‘Blue’ and Phalaenopsis Chih Shang's Stripes have been generated to introduce the blue color into the Phalaenopsis germplasm in prior study. In order to confirm the inheritance in hybrid progenies, genomic in situ hybridization (GISH) and restriction fragment length polymorphism (RFLP) analysis were conducted to confirm the intergeneric hybridization status.

Methods/Results

GISH analysis showed the presence of both maternal and paternal chromosomes in the cells of the putative hybrids indicating that the putative hybrid seedlings were intergeneric hybrids of the two parents. Furthermore, twenty-seven putative hybrids were randomly selected for DNA analysis, and the external transcribed spacer (ETS) regions of nrDNA were analyzed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and RFLP analyses to identify the putative hybrids. RFLP analysis showed that the examined seedlings were intergeneric hybrids of the two parents. However, PCR-RFLP analysis showed bias to maternal genotype.

Conclusions

Both GISH and RFLP analyses are effective detection technology to identify the intergeneric hybridization status of putative hybrids. Furthermore, the use of PCR-RFLP analysis to identify the inheritance of putative hybrids should be carefully evaluated.

Comparative transcriptome analysis of Gastrodia elata (Orchidaceae) in response to fungus symbiosis to identify gastrodin biosynthesis-related genes

BACKGROUND

Gastrodia elata Blume (Orchidaceae) is an important Chinese medicine with several functional components. In the life cycle of G. elata, the orchid develops a symbiotic relationship with two compatible mycorrhizal fungi Mycena spp. and Armillaria mellea during seed germination to form vegetative propagation corm and vegetative growth to develop tubers, respectively. Gastrodin (p-hydroxymethylphenol-beta-D-glucoside) is the most important functional component in G. elata, and gastrodin significantly increases from vegetative propagation corms to tubers. To address the gene regulation mechanism in gastrodin biosynthesis in G. elata, a comparative analysis of de novo transcriptome sequencing among the vegetative propagation corms and tubers of G. elata and A. mellea was conducted using deep sequencing.

RESULTS

Transcriptome comparison between the vegetative propagation corms and juvenile tubers of G. elata revealed 703 differentially expressed unigenes, of which 298 and 405 unigenes were, respectively up-regulated (fold-change ≥ 2, q-value < 0.05, the trimmed mean of M-values (TMM)-normalized fragments per kilobase of transcript per Million mapped reads (FPKM) > 10) and down-regulated (fold-change ≤ 0.5, q-value <0.05, TMM-normalized FPKM > 10) in juvenile tubers. After Gene Ontology (GO) annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, 112 up-regulated unigenes with KEGG Ortholog identifiers (KOids) or enzyme commission (EC) numbers were assigned to 159 isogroups involved in seventy-eight different pathways, and 132 down-regulated unigenes with KOids or EC numbers were assigned to 168 isogroups, involved in eighty different pathways. The analysis of the isogroup genes from all pathways revealed that the two unigenes TRINITY_DN54282_c0_g1 (putative monooxygenases) and TRINITY_DN50323_c0_g1 (putative glycosyltransferases) might participate in hydroxylation and glucosylation in the gastrodin biosynthetic pathway.

CONCLUSIONS

The gene expression of the two unique unigenes encoding monooxygenase and glycosyltransferase significantly increases from vegetative propagation corms to tubers, and the molecular basis of gastrodin biosynthesis in the tubers of G. elata is proposed.

Cinnamtannin D1 from Rhododendron formosanum Induces Autophagy via the Inhibition of Akt/mTOR and Activation of ERK1/2 in Non-Small-Cell Lung Carcinoma Cells

In our previous study, ursolic acid present in the leaves of Rhododendron formosanum was found to possess antineoplastic activity. We further isolated and unveiled a natural product, cinnamtannin D1 (CNT D1), an A-type procyanidin trimer in R. formosanum also exhibiting anticancer efficacy that induced G1 arrest (83.26 ± 3.11% for 175 μM CNT D1 vs 69.28 ± 1.15% for control, p < 0.01) and autophagy in non-small-cell lung carcinoma (NSCLC) cells. We found that CNT D1-mediated autophagy was via the noncanonical pathway, being beclin-1-independent but Atg5 (autophagy-related genes 5)-dependent. Inhibition of autophagy with a specific inhibitor enhanced cell death, suggesting a cytoprotective function for autophagy in CNT D1-treated NSCLC cells. Moreover, CNT D1 inhibited the Akt/mammalian target of the rapamycin (mTOR) pathway and activated the extracellular signal-regulated kinases 1/2 (ERK1/2) pathway, resulting in induction of autophagy.

Biogeography of the Phalaenopsis amabilis species complex inferred from nuclear and plastid DNAs

BACKGROUND

Phalaenopsis is one of the important commercial orchids in the world. Members of the P. amabilis species complex represent invaluable germplasm for the breeding program. However, the phylogeny of the P. amabilis species complex is still uncertain. The Phalaenopsis amabilis species complex (Orchidaceae) consists of subspecies amabilis, moluccana, and rosenstromii of P. amabilis, as well as P. aphrodite ssp. aphrodite, P. ap. ssp. formosana, and P. sanderiana. The aims of this study were to reconstruct the phylogeny and biogeographcial patterns of the species complex using Neighbor Joining (NJ), Maxinum Parsimony (MP), Bayesian Evolutionary Analysis Sampling Trees (BEAST) and Reconstruct Ancestral State in Phylogenies (RASP) analyses based on sequences of internal transcribed spacers 1 and 2 from the nuclear ribosomal DNA and the trnH-psbA spacer from the plastid DNA.

RESULTS

A pattern of vicariance, dispersal, and vicariance + dispersal among disjunctly distributed taxa was uncovered based on RASP analysis. Although two subspecies of P. aphrodite could not be differentiated from each other in dispersal state, they were distinct from P. amabilis and P. sanderiana. Within P. amabilis, three subspecies were separated phylogenetically, in agreement with the vicariance or vicariance + dispersal scenario, with geographic subdivision along Huxley's, Wallace's and Lydekker's Lines. Molecular dating revealed such subdivisions among taxa of P. amabilis complex dating back to the late Pleistocene. Population-dynamic analyses using a Bayesian skyline plot suggested that the species complex experienced an in situ range expansion and population concentration during the late Last Glacial Maximum (LGM).

CONCLUSIONS

Taxa of the P. amabilis complex with disjunct distributions were differentiated due to vicariance or vicariance + dispersal, with events likely occurring in the late Pleistocene. Demographic growth associated with the climatic oscillations in the Würm glacial period followed the species splits. Nevertheless, a subsequent population slowdown occurred in the late LGM due to extinction of regional populations. The reduction of suitable habitats resulted in geographic fragmenttation of the remaining taxa.

Structure Elucidation of Procyanidins Isolated from Rhododendron formosanum and Their Anti-Oxidative and Anti-Bacterial Activities

Rhododendron formosanum is an endemic species distributed in the central mountains of Taiwan. In this study, the biological activities of major procyanidins isolated from the leaf extract of R. formosanum were investigated. Four compounds, including two procyanidin dimers, procyanidin A1 (1) and B3 (2), and two procyanidin trimmers, procyanidin C4 (4) and cinnamtannin D1 (5), were isolated and identified on the basis of spectroscopic data. The structure of a new procyanidin dimer, rhodonidin A (3), was elucidated by 2D-NMR, CD spectrum and MS. The procyanidin trimmers and rhodonidin A are reported for the first time in Ericaceae. The biological activities of these procyanidins were evaluated using anti-bacterial and anti-oxidative assays. Only the new compound 3 demonstrated strong anti-bacterial activity against Staphylococcus aureus at an MIC value of 4 μg/mL. All compounds showed pronounced antioxidant activities and the activities are enhanced as the amount of OH groups in procyanidins increased. In conclusion, the pleiotropic effects of procyanidins isolated from the leaves of R. formosanum can be a source of promising compounds for the development of future pharmacological applications.

New bioactive chromanes from Litchi chinensis

Seven new δ-tocotrienols, designated litchtocotrienols A-G (1-7), together with one glorious macrocyclic analogue, macrolitchtocotrienol A (8), and one new meroditerpene chromane, cyclolitchtocotrienol A (9), were isolated from the leaves of Litchi chinensis. Their structures were mainly determined by extensive spectroscopic analysis, and their biological activities were evaluated by cytotoxicity against human gastric adenocarcinoma cell lines (AGS, ATCC CRL-1739) and hepatoma carcinoma cell line (HepG2 2.2.1.5). The structure-activity relationship of the isolated compounds was also discussed.

Evidence of purifying selection and co-evolution at the fold-back arm of the novel precursor microRNA159 gene in Phalaenopsis Species (Orchidaceae)

BACKGROUND

MicroRNAs (miRNAs) are small, endogenously transcribed, non-protein-coding RNAs that play important roles in regulation of gene expression in animals and plants. Here, selective constraints on the novel precursor microRNA159 (pre-miR159) gene were investigated in 42 Phalaenopsis species (Orchidaceae).

METHODS/RESULTS

A novel precursor microRNA159 gene was isolated from 42 Phalaenopsis species using a new microRNA-PCR (miR-PCR) approach. Sequencing of pre-miR159 genes revealed differences from the canonical pre-miR159 gene in Phalaenopsis species and other plants. Results demonstrated that the 5' and 3' fold-back arms and the terminal loop of the novel pre-miR159 gene have undergone purifying selection and selective constraint for stabilizing the secondary hairpin structure. Two conserved motifs within the 5' fold-back arm had the highest purifying selective pressure within the novel pre-miR159 gene. Evidence of sequence co-evolution between the 5' and 3' fold-back regions was observed.

CONCLUSIONS

Functional selective pressure might arise from the constraint of forming a hairpin structure and demonstrate co-evolution of sequences between the 5' and 3' fold-back regions of the novel pre-miR159 gene in Phalaenopsis species.

Adaptive divergence with gene flow in incipient speciation of Miscanthus floridulus/sinensis complex (Poaceae)

Young incipient species provide ideal materials for untangling the process of ecological speciation in the presence of gene flow. The Miscanthus floridulus/sinensis complex exhibits diverse phenotypic and ecological differences despite recent divergence (approximately 1.59 million years ago). To elucidate the process of genetic differentiation during early stages of ecological speciation, we analyzed genomic divergence in the Miscanthus complex using 72 randomly selected genes from a newly assembled transcriptome. In this study, rampant gene flow was detected between species, estimated as M = 3.36 × 10(-9) to 1.20 × 10(-6) , resulting in contradicting phylogenies across loci. Nevertheless, beast analyses revealed the species identity and the effects of extrinsic cohesive forces that counteracted the non-stop introgression. As expected, early in speciation with gene flow, only 3-13 loci were highly diverged; two to five outliers (approximately 2.78-6.94% of the genome) were characterized by strong linkage disequilibrium, and asymmetrically distributed among ecotypes, indicating footprints of diversifying selection. In conclusion, ecological speciation of incipient species of Miscanthus probably followed the parapatric model, whereas allopatric speciation cannot be completely ruled out, especially between the geographically isolated northern and southern M. sinensis, for which no significant gene flow across oceanic barriers was detected. Divergence between local ecotypes in early-stage speciation began at a few genomic regions under the influence of natural selection and divergence hitchhiking that overcame gene flow.

Synthesis and antiviral effects of isosteviol-derived analogues against the hepatitis B virus

Among several isosteviol-derived analogues, NC-8 (ent-16-oxobeyeran-19-N-methylureido) showed inhibitory potency against the hepatitis B virus (HBV) in HepG2 2.2.15 cells. Its anti-HBV mechanism was then next investigated in a human hepatoma cell culture system. Results showed that it specifically inhibited viral gene expression and reduced the level of encapsidated viral DNA intermediates in Huh7 cells that expressed replicating HBV. It also potently attenuated all viral promoter activity in HBV-expressing Huh7 cells, but not in cells lacking HBV expression. By examining its antiviral mechanism in cellular signaling pathways, NC-8 was found to inhibit the activity of the nuclear factor (NF)-κB element-containing promoter, but only slightly enhanced activities of activator protein (AP)-1- and interferon-sensitive response element (ISRE)-containing promoters in HBV-expressing cells. NC-8 also significantly eliminated NF-κB (p65/p50) and Toll-like receptor (TLR)2 proteins, but increased the IκBα protein level in a dose-dependent manner in HBV-transfected Huh7 cells, while these protein levels were apparently unchanged in non-transfected cells. Meanwhile, NC-8-treated nuclear extracts that co-expressed HBV inhibited the binding of NF-κB to the CS1 site of HBV major surface gene and specifically attenuated CS1-containing promoter activity. Taken together, this study suggests that the antiviral mechanism of NC-8 appears to be mediated by disturbing replication and gene expression of HBV and by inhibiting the host TLR2/NF-κB signaling pathway.

Chemical constituents of Rhododendron formosanum show pronounced growth inhibitory effect on non-small-cell lung carcinoma cells

The aim of the present study was to investigate whether Rhododendron formosanum Hemsl. (Ericaceae), an endemic species in Taiwan, exhibits antineoplastic potential against non-small-cell lung carcinoma (NSCLC). R. formosanum was successively extracted with methanol and then separated into dichloromethane (RFL-DCM), ethyl acetate (RFL-EA), n-butanol (RFL-BuOH), and water (RFL-H2O) fractions. Among these extracts, RFL-EA exhibited the most effective antineoplastic effect. This study also demonstrated that fractions 2 and 3 from the RFL-EA extract (RFL-EA-2, RFL-EA-3) possessed the strongest antineoplastic potential against NSCLC cells. The major phytochemical constituents of RFL-EA-2 and RFL-EA-3 were ursolic acid, oleanolic acid, and betulinic acid. This study indicated that ursolic acid demonstrated the most efficient antineoplastic effects on NSCLC cells. Ursolic acid inhibited growth of NSCLC cells in a dose- and time-dependent manner and stimulated apoptosis. Apoptosis was substantiated by activation of caspase-3 and -9, and a decrease in Bcl-2 and an elevation of the Bax were also observed following ursolic acid treatment. Ursolic acid activated AMP-activated protein kinase (AMPK) and then inhibited the mammalian target of rapamycin (mTOR), which controls protein synthesis and cell growth. Moreover, ursolic acid decreased the expression and/or activity of lipogenic enzymes, such as acetyl-CoA carboxylase (ACC) and fatty acid synthase (FASN) via AMPK activation. Collectively, these data provide insight into the chemical constituents and anticancer activity of R. formosanum against NSCLC cells, which are worthy of continued study.

Autointoxication mechanism ofOryza sativa : III. Effect of temperature on phytotoxin production during rice straw decomposition in soil

The phytotoxicity produced during decomposition of rice straw in soil was evaluated under both constant and changing temperature conditions. Bioassay tests showed that the aqueous extract from a soilstraw mixture after incubation at constant temperature was more than twice as phytotoxic as the extract from soil incubated alone. The phytotoxicity was highest at 20-25 ° C. Temperatures above 25 ° C enhanced rice straw decomposition and also degraded the phytotoxic substances more rapidly. After incubation of soil mixtures under changing temperature regimes in a phytotron, the phytotoxicy of the soil aqueous extracts increased in the following order: soil alone < soil + fertilizer < soil + straw < soil + straw + fertilizer. Growth inhibition of lettuce or rice seedlings was also at the highest at the temperature range of 25-30 ° C irrespective of the direction of temperature changes from either low to high or vice versa. Five phytotoxic phenolics,p-hydroxybenzoic, vanillic,p-coumaric, syringic, and ferulic acids, were obtained from both the aqueous extract and residue of the incubated soil samples and were quantitatively estimated by chromatography. The amount of phytotoxins found in various soil mixtures followed the same increasing order as that found by the seed bioassay test. Although no definite distribution pattern of the phenolics in the incubated soil samples can be attributed to temperature variations, the amount of the phenolics was likely higher in the samples incubated at 25 ° C than at either 15 ° C or 35 ° C. The quantity of toxins released during decomposition of rice straw in soil reached highest levels six weeks after incubation and gradually disappeared after twelve weeks.

The role of pentacyclic triterpenoids in the allelopathic effects of Alstonia scholaris

Alstonia scholaris is a tropical evergreen tree native to South and Southeast Asia. Alstonia forests frequently lack understory species. However, potential mechanisms-particularly the allelochemicals involved-remain unclear. In the present study, we identified allelochemicals of A. scholaris, and clarified the role of allelopathic substances from A. scholaris in interactions with neighboring plants. We showed that the leaves, litter, and soil from A. scholaris inhibited growth of Bidens pilosa-a weed found growing abundantly near A. scholaris forests. The allelochemicals were identified as pentacyclic triterpenoids, including betulinic acid, oleanolic acid, and ursolic acid by using (1)H and (13)C-NMR spectroscopy. The half-maximal inhibitory concentration (IC50) for radicle growth of B. pilosa and Lactuca sativa ranged from 78.8 μM to 735.2 μM, and ursolic acid inhibited seed germination of B. pilosa. The triterpenoid concentrations in the leaves, litter, and soil were quantified with liquid chromatography-electrospray ionization/tandem mass spectrometry. Ursolic acid was present in forest soil at a concentration of 3,095 μg/g, i.e., exceeding the IC50. In the field, ursolic acid accumulated abundantly in the soil in A. scholaris forests, and suppressed weed growth during summer and winter. Our results indicate that A. scholaris pentacyclic triterpenoids influence the growth of neighboring weeds by inhibiting seed germination, radicle growth, and functioning of photosystem II.

Allelopathic dominance ofMiscanthus transmorrisonensis in an alpine grassland community in Taiwan

A study site located at 2600 m elevation in Tartarchia Anpu, Nantou county, Taiwan, exhibits a unique grassland community composed of two principal species,Miscanthus transmorrisonensis andYushinia niitakayamensis, and 35 other species. The relative frequencies of the two species are 12% and 11%, while their relative coverages are 25% and 19.5%, respectively. The values for the remaining 35 species are lower than4% each, while species diversity of the community is -3.04839, indicating great diversity. To elucidate the mechanism of dominance ofM. transmorrisonensis, allelopathic evaluation of the plant was conducted. Aqueous extracts of M.Transmorrisonensis plant parts with two ecotypes were bioassayed. The extracts showed significant phytotoxic effects on seed germination and radicle growth of four tested plants: rye grass, lettuce, and two varieties of Chinese cabbage. In addition, rhizosphere soils underMiscanthus also exhibited significant phytotoxicity, indicating that allelopathic interaction was involved. Some responsible phytotoxic phenolics, namely, p-coumaric, ferulic, vanillic, protocatechuic, o-hydroxyphenylacetic, andm-hydroxyphenylacetic acids, and 4-hydroxycoumarin and phloridzin were identified. Allelopathy thus can play an important role in regulating plant diversity in the field.

Biological activity of oleanane triterpene derivatives obtained by chemical derivatization

Nine new derivatives of oleanane triterpenoids isolated from Fatsia polycarpa Hayata were synthesized through chemical transformations. Acetylation was effected by reaction with acetic anhydride in pyridine to afford compounds 1–5, while compound 6 was obtained using 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDC·HCl) in CH₂Cl₂. The others derivatives 7–9 were obtained in reactions of the corresponding triterpenoids with EDC·HCl, 4-N,N-dimethylaminopyridine hydrochloride and 4-N,N-dimethylaminopyridine in CH₂Cl₂. The structures of 1–9 were elucidated from extensive spectroscopic and HRESIMS data, while the structure of 9 was further confirmed by X-ray diffraction analysis. The cytotoxic, anti-hepatitis B virus (HBV), antibacterial, hypoglycaemic and Wnt signaling activities of these derivatives were evaluated in vitro.

Associations between serum total bilirubin levels and functional dependence in the elderly

BACKGROUND

Many studies support the role of bilirubin as a cytoprotector in chronic inflammatory diseases, such as stroke and atherosclerosis.

AIM

To investigate the relationship between serum total bilirubin levels and functional dependence in older adults.

METHODS

Data from the National Health and Nutrition Examination Survey (1999-2002) pertaining to 2235 old adults were analysed. All participants had given a household interview, providing information of five major domains on self-reported functional status (activities of daily living, instrumental activities of daily living, leisure and social activities, lower extremity mobility and general physical activities), had completed serum total bilirubin measurement, and a questionnaire regarding personal health. Poor performance was defined as experiencing difficulty with one or more items in a given domain. Functional dependence was defined as having three or more poor performances in the five major domains. Multiple logistic regression was performed together with quartile-based stratified odds ratio (OR) comparison and trend tests.

RESULTS

The OR of functional dependence for each standard deviation increment in the serum total bilirubin level was 0.56 (P = 0.002). After additional adjustment, the inverse association remained essentially unchanged. In quartile-based analysis, participants with higher quartiles of serum total bilirubin tended to have lower ORs of functional dependence. The trends of lower likelihood of functional dependence across increasing quartiles of the serum total bilirubin level were statistically significant (P < 0.05 for all trends).

CONCLUSIONS

Higher serum total bilirubin levels were associated with lower likelihood of functional dependence in older adults.

Autotoxicity mechanism of Oryza sativa: transcriptome response in rice roots exposed to ferulic acid

Background

Autotoxicity plays an important role in regulating crop yield and quality. To help characterize the autotoxicity mechanism of rice, we performed a large-scale, transcriptomic analysis of the rice root response to ferulic acid, an autotoxin from rice straw.

Results

Root growth rate was decreased and reactive oxygen species, calcium content and lipoxygenase activity were increased with increasing ferulic acid concentration in roots. Transcriptome analysis revealed more transcripts responsive to short ferulic-acid exposure (1- and 3-h treatments, 1,204 genes) than long exposure (24 h, 176 genes). Induced genes were involved in cell wall formation, chemical detoxification, secondary metabolism, signal transduction, and abiotic stress response. Genes associated with signaling and biosynthesis for ethylene and jasmonic acid were upregulated with ferulic acid. Ferulic acid upregulated ATP-binding cassette and amino acid/auxin permease transporters as well as genes encoding signaling components such as leucine-rich repeat VIII and receptor-like cytoplasmic kinases VII protein kinases, APETALA2/ethylene response factor, WRKY, MYB and Zinc-finger protein expressed in inflorescence meristem transcription factors.

Conclusions

The results of a transcriptome analysis suggest the molecular mechanisms of plants in response to FA, including toxicity, detoxicification and signaling machinery. FA may have a significant effect on inhibiting rice root elongation through modulating ET and JA hormone homeostasis. FA-induced gene expression of AAAP transporters may contribute to detoxicification of the autotoxin. Moreover, the WRKY and Myb TFs and LRR-VIII and SD-2b kinases might regulate downstream genes under FA stress but not general allelochemical stress. This comprehensive description of gene expression information could greatly facilitate our understanding of the mechanisms of autotoxicity in plants.

Characterization of 21 microsatellite markers from cogongrass, Imperata cylindrica (Poaceae), a weed species distributed worldwide

PREMISE OF THE STUDY

Microsatellite loci were developed from Imperata cylindrica, a traditional medicinal herb in Asia and among the top 10 worst invasive weeds in the world, to aid in the identification of the limits of asexual clonal individuals.

METHODS AND RESULTS

A total of 21 microsatellite markers, including 18 polymorphic and three monomorphic loci, were developed from I. cylindrica using a magnetic bead enrichment protocol. The primers amplified dinucleotide, trinucleotide, and complex repeats. The number of alleles ranged from one to 19 per locus, with an observed heterozygosity ranging from 0.09 to 1.00. Several loci deviated significantly from the within-population Hardy-Weinberg equilibrium as a result of asexual clonal reproduction.

CONCLUSIONS

These polymorphic markers should be useful tools in further studies on the identification of the range of clonal reproduction units and the selection and classification of the medicinal cultivar.

Intraspecific karyotypic polymorphism is highly concordant with allozyme variation in Lysimachia mauritiana (Primulaceae: Myrsinoideae) in Taiwan: implications for the colonization history and dispersal patterns of coastal plants

BACKGROUND AND AIMS

Investigating intraspecific karyotypic and genetic variations jointly can provide unique insights into how historical, ecological and cytogenetic factors influence microevolution. A coastal herb, Lysimachia mauritiana, exhibits extensive karyotypic polymorphism and displays a complex cytogeographic pattern across the Ryukyus. To explore whether a similar degree of chromosomal variation exists south of the Ryukyus, and in an attempt to ascertain the mechanisms that may have generated the patterns, comprehensive sampling was conducted in Taiwan.

METHODS

Karyotypes were analysed at mitotic metaphase for 550 individuals from 42 populations throughout Taiwan Proper and its adjacent islands. In addition, genetic variation was estimated using 12 allozymes (21 loci) of 314 individuals sampled from 12 localities.

KEY RESULTS

Four chromosome numbers and eight cytotypes, including four endemic cytotypes, were detected. Cytotype distributions were highly structured geographically, with single cytotypes present in most populations and four major cytotypes dominating the north, east and south of Taiwan and the Penghu Archipelago. Allozyme variation was very low and F-statistics indicated an extremely high level of population differentiation, implying limited gene flow among populations. Cluster analysis of allozyme variation uncovered four geographic groups, each corresponding perfectly to the four dominant cytotypes. The geographic structure of cytotype distribution and allozyme variation probably resulted from severe genetic drift triggered by genetic bottlenecks, suggesting that Taiwanese populations were likely to be derived from four independent founder events. In the few localities with multiple cytotypes, cytogeographic patterns and inferences of chromosomal evolution revealed a trend of northward dispersal, consistent with the course of the Kuroshio Current that has been influential in shaping the coastal biota of the region.

CONCLUSIONS

The data elucidate the patterns of colonization and the effects of the Kuroshio Current on the distribution of L. mauritiana in Taiwan. These inferences are highly relevant to other coastal plant species in the region and will stimulate further studies.

Introgression between cultivars and wild populations of Momordica charantia L. (Cucurbitaceae) in Taiwan

The landrace strains of Momordica charantia are widely cultivated vegetables throughout the tropics and subtropics, but not in Taiwan, a continental island in Southeast Asia, until a few hundred years ago. In contrast, the related wild populations with smaller fruit sizes are native to Taiwan. Because of the introduction of cultivars for agricultural purposes, these two accessions currently exhibit a sympatric or parapatric distribution in Taiwan. In this study, the cultivars and wild samples from Taiwan, India, and Korea were collected for testing of their hybridization and evolutionary patterns. The cpDNA marker showed a clear distinction between accessions of cultivars and wild populations of Taiwan and a long divergence time. In contrast, an analysis of eight selectively neutral nuclear microsatellite loci did not reveal a difference between the genetic structures of these two accessions. A relatively short divergence time and frequent but asymmetric gene flows were estimated based on the isolation-with-migration model. Historical and current introgression from cultivars to wild populations of Taiwan was also inferred using MIGRATE-n and BayesAss analyses. Our results showed that these two accessions shared abundant common ancestral polymorphisms, and the timing of the divergence and colonization of the Taiwanese wild populations is consistent with the geohistory of the Taiwan Strait land bridge of the Last Glacial Maximum (LGM). Long-term and recurrent introgression between accessions indicated the asymmetric capacity to receive foreign genes from other accessions. The modern introduction of cultivars of M. charantia during the colonization of Taiwan by the Han Chinese ethnic group enhanced the rate of gene replacement in the native populations and resulted in the loss of native genes.

Associating emergency room visits with first and prolonged extreme temperature event in Taiwan: A population-based cohort study

The present study evaluated emergency room visit (ERV) risks for all causes and cardiopulmonary diseases associated with temperature and long-lasting extreme temperatures from 2000 to 2009 in four major cities in Taiwan. The city-specific daily average temperatures at the high 95th, 97th, and 99th percentiles, and the low 10th, 5th, and 1st percentiles were defined as extreme heat and cold. A distributed lag non-linear model was used to estimate the cumulative relative risk (RR) of ERV for morbidities associated with temperatures (0 to 3-day lags), extreme heat and cold lasting for 2 to 9 days or longer, and with the annual first extreme heat or cold event after controlling for covariates. Low temperatures were associated with slightly higher ERV risks than high temperatures for circulatory diseases. After accounting for 4-day cumulative temperature effect, the ERV risks for all causes and respiratory diseases were found to be associated with extreme cold at the 5th percentile lasting for >8 days and 1st percentile lasting for >3 days. The annual first extreme cold event of 5th percentile or lower temperatures was also significantly associated with ERV, with RRs ranging from 1.09 to 1.12 for all causes and from 1.15 to 1.26 for respiratory diseases. The annual first extreme heat event of 99th percentile temperature was associated with higher ERV for all causes and circulatory diseases. Annual first extreme temperature event and intensified prolonged extreme cold events are associated with increased ERVs in Taiwan.

Antihepatitis B virus constituents of Solanum erianthum

Eleven compounds were isolated from the methanolic extract of the leaves of Solanum erianthum D. Don, including five alpha-linolenic acid analogs, alpha-linolenic acid (1), 13S-hydroxy-9(Z),11(E)-octadecadienoic acid (2), 9S-hydroxy-10(E),12(Z), 15(Z)-octadectrienoic acid (3), 9(Z),11(E)-octadecadienoic acid (4), and octadecanoic acid (5); two benzofuran-type lactones, loliolide (6) and dihydroactinidiolide (7); two steroidal alkaloids, solasonine (8) and solamargine (9); a flavonol glycoside, camelliaside C (10); and a flavone, 5-methoxy-(3,4"-dihydro-3",4"-diacetoxy)-2",2'-dimethylpyrano-(7,8:5",6")-flavone (11). Among these isolated compounds, 9 showed the most potent activity against HBsAg, with an IC50 of 1.57 microM, followed by 8 (IC50 is 5.89 microM). In the testing against HBeAg, 11 was the only active compound with an IC50 of 36.11 microM. Compound 9 also revealed strong inhibition of DNA replication towards HBV and its IC50 was 2.17 microM. However, alpha-linolenic acid (1) showed a prominent selected index (SI), both in anti-HBsAg and inhibition of DNA replication with SI values of 7.75 and 7.18, respectively. This is the first report that unsaturated fatty acid 1, steroidal alkaloid glycoside 9 and flavone 11, all showed excellent activity against HBV. These results provide lead candidates in the development of anti-HBV drugs from natural sources.

Antihepatitis B Virus Constituents of Solanum Erianthum

Eleven compounds were isolated from the methanol extract of the leaves of Solanum erianthum D. Don, including five α-linolenic acid analogs, α-linolenic acid (1), 13 S-hydroxy-9( Z),11( E)-octadecadienoic acid (2), 9S-hydroxy-10( E),12( Z), 15( Z)-octadectrienoic acid (3), 9( Z),11( E)-octadecadienoic acid (4), and octadecanoic acid (5); two benzofuran-type lactones, loliolide (6) and dihydroactinidiolide (7); two steroidal alkaloids, solasonine (8) and solamargine (9); a flavonol glycoside, camelliaside C (10); and a flavone, 5-methoxy-(3″,4″-dihydro-3″,4″-diacetoxy)-2″,2″-dimethylpyrano-(7,8:5″,6″)-flavone (11). Among these isolated compounds, 9 showed the most potent activity against HBsAg, with an IC50 of 1.57 μM, followed by 8(IC50 is 5.89 μM). In the testing against HBeAg, 11 was the only active compound with an IC50 of 36.11 μM. Compound 9 also revealed strong inhibition of DNA replication towards HBV and its IC50 was 2.17 μM. However, α-linolenic acid (1) showed a prominent selected index (SI), both in anti-HBsAg and inhibition of DNA replication with SI values of 7.75 and 7.18, respectively. This is the first report that unsaturated fatty acid 1, steroidal alkaloid glycoside 9 and flavone 11, all showed excellent activity against HBV. These results provide lead candidates in the development of anti-HBV drugs from natural sources.

Oleanane-type triterpenoids from the leaves and twigs of Fatsia polycarpa

Seven new oleanane-type triterpenoids (1-7), named fatsicarpains A-G, and the known compounds 3α-hydroxyolean-11,13(18)-dien-28-oic acid (8) and 3α-hydroxyolean-11-en-28,13β-olide (9) were isolated from the leaves and twigs of Fatsia polycarpa on the basis of bioassay-guided fractionation. The structures of compounds 1-7 were elucidated through spectroscopic analyses and single-crystal X-ray crystallography of 1, 8, and 9. Cytotoxicity against HepG2 2.2.15 and AGS cells and antihepatitis B virus (HBV) and antibacterial activities of 1-9 were also evaluated in vitro.

Infections caused by Gordonia species at a medical centre in Taiwan, 1997 to 2008

The inability of conventional identification systems to accurately identify Gordonia spp. often results in the misdiagnosis of infections by these rare pathogens, which require genomic sequencing for precise identification. In the present study, we describe nine cases of the various types of infection caused by Gordonia spp. From 1997 to 2008, 66 isolates (from 30 patients) initially identified as Rhodoccus spp. by conventional biochemical methods, by the Bacteriology Laboratory of National Taiwan University Hospital, were retrospectively analysed to assess the accuracy of species identification. Fifteen of these isolates (from nine patients) were later found to be Gordonia spp. by two molecular methods: PCR-restriction fragment length polymorphism for heat shock protein gene (hsp65) and the 16S rRNA gene sequencing analysis. Gordonia sputi (n = 8) was the most common species, followed by Gordonia terrae (n = 7). Most of the isolates were isolated from blood (n = 11), followed by soft tissue (n = 2) and eye (n = 2). Five patients presented with bacteraemia and two of these had catheter-related bloodstream infection. Two patients had soft tissue infections and another two patients had infective keratitis and conjunctivitis. The random amplified polymorphic DNA patterns for isolates from different patients were different, indicating that they were genetically unrelated. Accurate identification with molecular methods is required if the role of Gordonia spp. in causing infection is to be recognized.

Cardiovascular mortality during heat and cold events: determinants of regional vulnerability in Taiwan

OBJECTIVES

To identify the vulnerable regions with underlying susceptibility and poor adaptive capability in response to cold and heat events in Taiwan, and to characterise the determinants associated with such an increasing risk to design better adaptive strategies in view of predicted weather changes in the future.

METHODS

The authors used spatial regression models to measure the relationships between the spatial characteristics of temperature, extracted factors from demographic and socio-economic parameters, and the mean cardiovascular mortality 2 weeks before and after cold or heat events from 1994 to 2003.

RESULTS

Metropolitan regions were found to have a substantially lower mortality than rural areas after cold and heat events. Events of cold, compared with heat, had greater impacts on the mortality ratio in most townships. A negative association was identified, using a spatial lag model, between the mortality after cold and heat events and urbanisation, and the availability of medical resources. A higher percentage of older people, vulnerable and aborigines might have contributed to the increasing vulnerability of townships during cold and heat events.

CONCLUSIONS

These data, using an island-wide spatial analysis, suggest that urban areas have a greater adaptive capability than rural areas, plausibly because people in urban areas have a higher socio-economic status and more medical resources. Social inequality across urban and rural townships is apparent and developing customised adaptation programmes for vulnerable regions to cope with heat and cold event should be prioritised.

Activation of p38 MAPK by damnacanthal mediates apoptosis in SKHep 1 cells through the DR5/TRAIL and TNFR1/TNF-α and p53 pathways

The effect of the natural compound damnacanthal from Morinda citrifolia on SKHep 1 cell growth regulation was investigated. Treatment of SKHep 1 cells with damnacanthal for 24h indicated a dose-dependent antiproliferative activity. Damnacanthal seems to be selective for tumor cell lines, since there is only minimal toxicity against normal hepatocyte cells (FL83B). This is first demonstration that damnacanthal-mediated apoptosis involves the sustained activation of the p38 MAPK pathway, leading to the transcription of the death receptor family genes encoding DR5/TRAIL and TNF-R1/TNF-α genes as well as the p53-regulated Bax gene. The damnacanthal-mediated expression of DR5/TRAIL and TNF-R1/TNF-α results in caspase 8 activation, leading to Bid cleavage. In turn, activated Bid, acting with p53-regulated Bax, leads to cytochrome c released from mitochondria into the cytoplasm. Combined activation of the death receptors and mitochondrial pathways results in activation of the downstream effecter caspase 3, leading to cleavage of PARP. TRAIL- and TNF-α-mediated damnacanthal-induced apoptosis could be suppressed by treatment with caspase inhibitors as well as soluble death receptors Fc:DR5 and Fc:TNF-R1 chimera. Taken together, this study provided first evidence demonstrating that TRAIL-, TNF-α-, and p53-mediated damnacanthal-induced apoptosis require the activation of p38 MAPK and mitochondrion-mediated caspase-dependent pathways.

Solanum torvum inhibits Helicobacter pylori growth and mediates apoptosis in human gastric epithelial cells

Helicobacter pylori infection is associated with an increased risk for development of duodenal ulcers, gastric ulcers, gastric adenocarcinomas and gastric lymphomas. However, resistant strains have developed because of antibiotic treatment. In this study, the water, acetone, chloroform and methanol extracts of two Solancaceae plants, Solanum erianthum and Solanum torvum (ST), were tested for their anti-H. pylori activity. All of ST extracts were able to inhibit the growth of H. pylori and showed better activities against antibiotic strains than the reference strain. Among them, chloroform extract of ST (ST-C) possessed the strongest ability to inhibit H. pylori growth. Association assay was performed by the ST-C showing that ST-C was able to interrupt the association of bacteria to host cells. Furthermore, H. pylori-induced apoptosis could also be efficiently suppressed by the ST-C. It was able to interfere with the interaction between bacteria and host cells and also target H. pylori-induced gastric injury by suppressing apoptosis. Therefore, ST-C may offer a new approach for the treatment of H. pylori. Further studies on the elucidation of the molecular mechanisms of the growth inhibition on H. pylori by ST-C, and to identify active compounds in the plants are in progress.

The chondroprotective effects of ferulic acid on hydrogen peroxide-stimulated chondrocytes: inhibition of hydrogen peroxide-induced pro-inflammatory cytokines and metalloproteinase gene expression at the mRNA level

OBJECTIVE

The objective of the study is to evaluate the effect of ferulic acid (FA), an antioxidant from the Chinese herb Dong-Gui [Chinese angelica, Angelica sinensis (Oliv.) Diels], on the regulation of various genes in hydrogen peroxide-stimulated porcine chondrocytes at the mRNA level.

METHODS

The effect of FA and the effective concentration of FA on porcine chondrocytes was evaluated by the lactate dehydrogenase, WST-1, crystal violet assay, and a chemical luminescence assay. Gene expression in hydrogen peroxide-stimulated chondrocytes either pre- or post-treated with FA was evaluated by real-time PCR.

RESULTS

Chondrocytes pre-treated with 40 microM FA decreased the hydrogen peroxide-induced interleukin-1beta (IL-1beta), tumor necrosis factor-alpha (TNF-alpha), and MMP-1 and partially restored SOX9 gene expression. Post-treatment with 40 microM FA also decreased the expression of MMP-1 and MMP-13.

CONCLUSION

FA decreased the hydrogen peroxide-induced IL-1beta, TNF-alpha, MMP-1 and MMP-13 and increased SOX9 gene expression. These findings suggest that FA may prove to be important in the treatment of osteoarthritis. Further research is needed.

Genetic manipulation of stationary-phase genes to enhance recombinant protein production in Escherichia coli

Genetic manipulation of the host strain, by which cell physiology could be modulated, was exploited to enhance recombinant protein production in Escherichia coli. The effects of an inactivated stationary-phase gene (rmf or katF) on recombinant protein production in strains with two different expression systems (the pH-inducible and the lac promoters) were investigated. An improvement of recombinant protein production in the katF mutant at low growth rates was observed for both expression systems. A fourfold and a 30% increase in the volumetric recombinant protein activity were observed for the pH-inducible and the lac promoter system, respectively. The effect of the rmf mutation, on the other hand, depends on the expression system. A twofold increase in the volumetric recombinant protein activity was found for the pH-inducible promoter system, but there was no improvement for the lac promoter system. Improvement in culture performance for slow-growing cultures may have an impact on the design strategy of the host/vector system used in fed-batch cultures, where the specific growth rate is usually slow. The information may also be useful for developing optimal host/vector gene expression systems for recombinant protein production.

Patient-driven loop control for ambulation function restoration in a non-invasive functional electrical stimulation system

PURPOSE

In this study, a patient-driven loop control in a non-invasive functional electrical stimulation (FES) system was designed to restore ambulation function of patients with stroke with their residual capabilities.

METHOD

With this patient-driven loop control, patients use the electromyographic (EMG) signals from their voluntary controlled muscles in affected extremity to adjust stimulus parameters of the system. A special designed FES system generated electrical stimuli to excite the paralysed muscles through surface electrodes on the basis of the control command from the residual myoelectric signals. The EMG signals were also served as the trigger and the adjustment of stimulus parameters and thereby adding versatility of the FES system. One patient with hemiplegia was recruited to conduct clinical evaluation and treated by using the new closed-loop FES system.

RESULTS

The experimental results showed that hemiplegic could successfully control the system to restore their lost ambulation functions with the strategy of patient-driven loop control. It is revealed that the mean velocity, cadence, stride length, active ankle motion range and functional ambulation category have improved significantly from 0.22 + or - 0.17 m/s, 37.3 + or - 15.5 steps/min, 0.32 + or - 0.11 m, 10 degrees , level 2 to 0.46 + or - 0.23 m/s, 58.2 + or - 19.1 steps/min, 0.73 + or - 0.22 m, 35 degrees , level 4 respectively for the patient. A paired t-test indicated that differences in the EMG of the tibialis anterior and the gastrocnemius muscles between patient's disabled (affected-side) foot and normal (unaffected-side) foot are not significant (p > 0.05) after 12 weeks of training.

CONCLUSIONS

According to the experiment results, this patient-driven loop control can be beneficial for patient with hemiplegia to restore their ambulation functions such as dorsi-flexion and plantar-flexion. The control strategy of this study has the potential to be employed not only in the FES system but also in other assistive devices.

Diagnostic performance of an enzyme-linked immunospot assay for interferon-gamma in extrapulmonary tuberculosis varies between different sites of disease

OBJECTIVES

To evaluate diagnostic performance of an enzyme-linked immunospot assay for interferon-gamma (T SPOT-TB) in patients with suspected extrapulmonary tuberculosis (TB).

METHODS

From January 2007 to December 2008, patients with suspected extrapulmonary TB were prospectively enrolled from 2 tertiary care hospitals.

RESULTS

A total of 138 patients with suspected extrapulmonary TB were enrolled; 50 patients had positive culture for Mycobacterium tuberculosis and 39 patients had probable TB. The sites of infection were lymph node (n = 20), pleura (n = 19), bone/joint (n = 15), urinary tract (n = 7), peritoneum (n = 7), meninges (n = 6), disseminated (n = 5), intestine (n = 3), pericardium (n = 2), skin (n = 2), throat (n = 1), neck (n = 1), and genitalia (n = 1). The overall sensitivity and specificity were 79.8% (71/89) and 81.6% (40/49). The sensitivity ranged from 100% for tuberculous meningitis, tuberculous pericarditis, and intestinal TB, 95% for lymphadenitis, to 42.9% for tuberculous peritonitis. The sensitivity of the T SPOT-TB assay was 70.6% in immunocompromised patients and 85.5% in immunocompetent patients (p = 0.09).

CONCLUSIONS

The T SPOT-TB assay can be a useful tool for diagnosing extra-pulmonary TB in immunocompetent and immunocompromised patients, particularly for tuberculous meningitis, pericarditis, lymphadenitis, and intestinal TB.