Discovery of Unusual Ajmaline-Macroline Type Bisindole Alkaloids from Alstonia macrophylla by Building Blocks-Based Molecular Networking

Three unusual ajmaline-macroline type bisindole alkaloids, alsmaphylines A-C, together with their postulated biogenetic precursors, were isolated from the stem barks and leaves of Alstonia macrophylla via the building blocks-based molecular network (BBMN) strategy. Alsmaphyline A represents a rare ajmaline-macroline type bisindole alkaloid with an S-shape polycyclic ring system. Alsmaphylines B and C are two novel ajmaline-macroline type bisindole alkaloids with N-1-C-21' linkages, and the former possesses an unconventional stacked conformation due to the presence of intramolecular noncovalent interactions. The chemical structures including absolute configurations of alsmaphylines A-C were established by comprehensive spectroscopic analyses, electronic circular dichroism (ECD) calculations, and single-crystal X-ray crystallography. In addition, a plausible biosynthetic pathway of these bisindole alkaloids as well as their ability to promote the protein synthesis on HT22 cells were discussed.

Five New Phenylpropanoyl Phloroglucinol Derivatives from Leptospermum scoparium

Leptosperols C-G (1-5), five new phenylpropanoyl phloroglucinol derivatives were isolated from the leaves of Leptospermum scoparium. Compounds 1-3 are phenylpropanoyl phloroglucinol-sesquiterpene adducts with new carbon skeletons. Their structures with absolute configurations were elucidated by detailed spectroscopic analyses, single-crystal X-ray diffraction, and electronic circular dichroism (ECD) calculation. Compounds 2 and 3 exhibited moderate anti-inflammatory activity in zebrafish acute inflammatory models.

Stilbenes from the leaves of Cajanus cajan and their in vitro anti-inflammatory activities

Eighteen stilbenes (1-18), including six previously undescribed ones (1-6), with diverse modification patterns were isolated from the leaves of edible and medicinal plant Cajanus cajan. Among the new isolates, compounds 1-3 were initially obtained as three racemic mixtures, which were further resolved into three pairs of optically pure enantiomers, respectively, by chiral HPLC. Besides, compounds 8, 10, 11, and 18 were obtained from C. cajan for the first time. The chemical structures and absolute configurations of the new stilbenes were elucidated unambiguously on the basis of extensive spectroscopic analyses, single crystal X-ray crystallographic study, and quantum chemical electronic circular dichroism (ECD) calculations. In addition, the in vitro anti-inflammatory activities of all isolated stilbenes were evaluated. Compounds 2, 9, 10, 11, and 14 exerted moderate suppression of nitric oxide (NO) secretion in lipopolysaccharide (LPS)-induced RAW264.7 cells without exhibiting substantial cytotoxicity.

Angiogenesis-Inhibitory Piperidine Alkaloids from the Leaves of Microcos paniculata

Eight new 2,6-disubstituted piperidin-3-ol alkaloids (1-8), featuring a C₁₀ unsaturated alkyl side chain, together with three previously reported analogues (9-11) were isolated from the leaves of medicinal plant Microcos paniculata. Their structures and absolute configurations were elucidated unambiguously by means of 1D and 2D NMR spectroscopic data analysis, modified Mosher's method, Snatzke's method, and quantum chemical electronic circular dichroism (ECD) calculations, as well as single-crystal X-ray crystallography. The isolates were evaluated for their antiangiogenic effects on human umbilical vein endothelial cells (HUVECs). Compound 2 displayed an inhibitory effect on tube formation of HUVECs in a concentration-dependent manner.

Securinine Promotes Neuronal Development and Exhibits Antidepressant-like Effects via mTOR Activation

Impaired differentiation of newborn neurons or abnormalities at the synapses resulted from stress maladaptation could be the key etiology of depression. Recent studies have shown that mTOR, a crucial factor for neuronal differentiation and synapse development, acts as a common factor that mediates the rapid antidepression effects of several new-class antidepressants. In this study, the antidepressant-like activity of securinine, an alkaloid that has central nervous system stimulation ability, was investigated. Both securinine and its enantiomer virosecurinine exhibited potent in vitro activity on neuronal differentiation and synapse development in Neuro-2a cells and cultured hippocampal neurons, and this activity was dependent on the activation of the AKT-mTOR-S6K pathway. Interestingly, only securinine but not virosecurinine showed mTOR stimulation and antidepressant-like activity in mice. Importantly, a single dose of securinine was capable of alleviating the behavioral deficits induced by both acute and chronic stress models within 30 min of administration, suggesting that securinine has rapid onset of action. Moreover, neither a single dose nor a 3 week treatment of securinine had adverse effects on exploratory locomotion of mice. Together, this study identifies that securinine is a potent agent in promoting neuronal differentiation and synapse formation and shows rapid antidepressant-like activity, without inducing abnormal locomotion, via mTOR activation.

Quassinoids from the Roots of Eurycoma longifolia and Their Anti-Proliferation Activities

A phytochemical investigation on the roots of medicinal plant Eurycoma longifolia resulted in the isolation of 10 new highly oxygenated C₂₀ quassinoids longifolactones G‒P (1–10), along with four known ones (11–14). Their chemical structures and absolute configurations were unambiguously elucidated on the basis of comprehensive spectroscopic analysis and X-ray crystallographic data. Notably, compound 1 is a rare pentacyclic C₂₀ quassinoid featuring a densely functionalized 2,5-dioxatricyclo[5.2.2.0^4,8]undecane core. Compound 4 represents the first example of quassinoids containing a 14,15-epoxy functionality, and 7 features an unusual α-oriented hydroxyl group at C-14. All isolated compounds were evaluated for their anti-proliferation activities on human leukemia cells. Among the isolates, compounds 5, 12, 13, and 14 potently inhibited the in vitro proliferation of K562 and HL-60 cells with IC₅₀ values ranging from 2.90 to 8.20 μM.

[Two new pyranonaphthoquinones from Mansoa alliacea]

Mansoa alliacea,commonly known as garlic vine,is native to the tropical rain forests of South America and widely cultivated in South China. As a popular folk medicine with various biological activities,however,this plant remains to be fully elucidated in terms of its phytochemical constituents. In this study,two new pyranonaphthoquinones were isolated from the 95% ethanol extract of the leaves and twigs of M. alliacea by various chromatographic approaches including silica gel,octadecyl silica( ODS),Sephadex LH-20,and preparative high-performance liquid chromatography( PHPLC). Their structures were determined to be 8,9-dimethoxy-α-lapachone( 1) and 7-hydroxy-8,9-dimethoxy-α-lapachone( 2) by comprehensive spectroscopic analyses and therefore respectively named as mansonin A( 1) and mansonin B( 2).

Discovery of Neuritogenic Securinega Alkaloids from Flueggea suffruticosa by a Building Blocks-Based Molecular Network Strategy

A combined strategy of building blocks recognition and molecular network construction, termed the building blocks-based molecular network (BBMN), was first presented to facilitate the efficient discovery of novel natural products. By mapping the BBMN of the total alkaloid fraction of Flueggea suffruticosa, three Securinega alkaloids (SEAs) with unusual chemical architectures, suffranidines A-C (1-3), were discovered and isolated. Compound 1 characterizes an unprecedented 8/5/6/5/6/6/6/6-fused octacyclic scaffold with a unique cage-shaped 3-azatricyclo[6.4.0.0^3,11 ]dodecane core. Compounds 2 and 3 are highly modified SEA dimers that incorporate additional C6 motifs. A hypothetical biosynthetic pathway for 1-3 was proposed. In addition, 1 significantly induced neuronal differentiation and neurite extension by upregulating eukaryotic elongation factor 2 (eEF2)-mediated protein synthesis.

Cajanusoids A-D, Unusual Atropisomeric Stilbene Dimers with PTP1B Inhibitory Activities from the Leaves of Cajanus cajan

Four novel stilbene dimers (1-4), together with their biosynthetically related stilbene monomers (5 and 6), were isolated from the leaves of Cajanus cajan. Their structures with absolute configurations were determined by comprehensive analysis of spectroscopic data and electronic circular dichroism calculations. Compounds 1 and 2 are two novel dimeric stilbenes with an unusual coupling pattern that resulted in a rare configurationally stable Csp²-Csp³ chiral axis with both point and axial chirality in their molecules. Due to their unique inherent structural features, both of them naturally occur as equilibrating mixtures of unequally populated atropo-diastereomers and their respective enantiomers. Compounds 3 and 4 are two pairs of novel dimeric stilbene atropisomers featuring a rotationally hindered central biaryl axis. Notably, 3 contains a rare arylbenzoquinone core and 4 is a symmetric dimer with a C₂ symmetry axis. The hypothetical biosynthetic pathway of 1-4 was also proposed herein. All the new compounds exhibited significant protein tyrosine phosphatase-1B (PTP1B) inhibition effects. In addition, the preliminary mode of action for the most potent compound 3 was investigated by molecular docking and binding free energy calculation.

Alkaloid constituents from the fruits of Flueggea virosa

Three new indole alkaloids, flueindolines A-C (1-3), along with nine known alkaloids (4-12), were isolated from the fruits of Flueggea virosa (Roxb. ex Willd.) Voigt. Compounds 1 and 2 are two new fused tricyclic indole alkaloids possessing an unusual pyrido[1, 2-a]indole framework, and 3 presents a rare spiro (pyrrolizidinyl-oxindole) backbone. Their structures with absolute configurations were elucidated by means of comprehensive spectroscopic analysis, chemical calculation, as well as X-ray crystallography. Chiral resolution and absolute configuration determination of the known compounds 4, 10, and 11 were reported for the first time. The hypothetical biogenetical pathways of 1-3 were herein also proposed.

[A new flavonostilbene glycoside from roots of Polygonum multiflorum]

Polygonflavanol B(1), a new flavonostilbene glycoside, was isolated from the roots of Polygonum multiforum(Polygonaceae) by various column chromatography methods including macroporous resin HP-20, silica gel, Sephadex LH-20, and preparative HPLC. The structure with absolute configuration of the new compound was identified by its physicochemical properties, spectroscopic data, ECD calculation, and chemical method.

Heterologous Biosynthesis of Type II Polyketide Products Using E. coli

The heterologous biosynthesis of complex natural products has enabled access to polyketide, nonribosomal peptide, isoprenoid, and other compounds with wide-spanning societal value. Though several surrogate host systems exist, Escherichia coli is often a preferred choice due to its rapid growth kinetics and extensive molecular biology protocols. However, a persistent challenge to the utilization of E. coli has been the successful in vivo reconstitution of type II polyketide synthase (PKS) systems. In particular, gene expression of the ketosynthase (KS) components of the minimal PKS has consistently yielded insoluble protein products. In the following report, two type II PKS systems were functionally reconstituted in E. coli. The approach to do so relied upon the utilization of the native transcriptional coupling between the dimeric KS subunits, leading to soluble recombinant protein products and successful polyketide biosynthesis. Resulting strains produced 10 mg/L TW95c and 25 mg/L dehydrorabelomycin. Hence, the strategy offers a new option in the biosynthetic engineering efforts for the heterologous production of type II polyketide products using E. coli.

Dimeric Diarylheptanoids with Neuroprotective Activities from Rhizomes of Alpinia officinarum

Two novel dimeric diarylheptanoids, alpinidinoids A [(±)-1] and B (2), with two unusual coupling patterns, together with a new naturally occurring diarylheptanoid dimer possessing a rare pyridine ring linkage (alpinidinoid C, 3), were isolated from the rhizomes of Alpinia officinarum. Their structures including absolute configurations were determined by extensive spectroscopic methods and theoretical calculations. All isolates were examined for their neuroprotective activities against oxygen-glucose deprivation and reoxygenation (OGD/R) damage in primary cortical neurons. Remarkably, the dextrorotatory enantiomer of alpinidinoid A [(+)-1] significantly ameliorated OGD/R-induced neuronal apoptosis, which was dependent on the activation of the AKT/mTOR signaling pathway.

Absolute Configurations and Stereochemical Inversion Mechanism of Epimeric Securinega Alkaloids from Flueggea suffruticosa

Three pairs of Securinega alkaloid epimers with a piperidin-2-yl moiety (1-6) were isolated from Flueggea suffruticosa, and their structures including absolute configurations were definitely characterized. An interconvertible C-2' epimerization process within each pair of epimers was observed. The following comprehensive experimental and theoretical investigations demonstrated an unusual stereochemical inversion mechanism of an N-substituted carbon stereogenic center, which was evidenced to be a protic solvent mediated process involving a tandem 1,4-elimination/1,4-addition as the key step.

Eleven New Triterpenoid Glycosides from the Roots of Ilex asprella

Asprellosides A-K, nine new ursane-type triterpenoid glycosides (1-9), and two new oleanane-type triterpenoid glycosides (10 and 11), including six rare sulfated triterpenoid glycosides, were isolated from the roots of Ilex asprella. Their structures were determined on the basis of comprehensive spectroscopic analysis and chemical methods. Among these compounds, asprelloside B (2) and asprelloside C (3) are the first examples of triterpenoid glycosides bearing a rare 3,4-O-disulfo-xylopyranosyl residue. All the saponins isolated showed no significant effects against respiratory syncytial virus (RSV) and lipopolysaccharide-induced nitric oxide production in Raw264.7 macrophages.

Flueggeacosines A-C, Dimeric Securinine-Type Alkaloid Analogues with Neuronal Differentiation Activity from Flueggea suffruticosa

Flueggeacosines A-C (1-3), three dimeric securinine-type alkaloid analogues with unprecedented skeletons, were isolated from Flueggea suffruticosa. Compounds 1 and 2 are the first examples of C-3-C-15' connected dimeric securinine-type alkaloids. Compound 3 is an unprecedented heterodimer of securinine-type and benzoquinolizidine alkaloids. Biosynthetic pathways for 1-3 were proposed on the basis of the coexisting alkaloid monomers as the precursors. Compound 2 exhibited significant activity in promoting neuronal differentiation of Neuro-2a cells.

Sex-specific relevance of diabetes to occlusive vascular and other mortality: a collaborative meta-analysis of individual data from 980 793 adults from 68 prospective studies

BACKGROUND

Several studies have shown that diabetes confers a higher relative risk of vascular mortality among women than among men, but whether this increased relative risk in women exists across age groups and within defined levels of other risk factors is uncertain. We aimed to determine whether differences in established risk factors, such as blood pressure, BMI, smoking, and cholesterol, explain the higher relative risks of vascular mortality among women than among men.

METHODS

In our meta-analysis, we obtained individual participant-level data from studies included in the Prospective Studies Collaboration and the Asia Pacific Cohort Studies Collaboration that had obtained baseline information on age, sex, diabetes, total cholesterol, blood pressure, tobacco use, height, and weight. Data on causes of death were obtained from medical death certificates. We used Cox regression models to assess the relevance of diabetes (any type) to occlusive vascular mortality (ischaemic heart disease, ischaemic stroke, or other atherosclerotic deaths) by age, sex, and other major vascular risk factors, and to assess whether the associations of blood pressure, total cholesterol, and body-mass index (BMI) to occlusive vascular mortality are modified by diabetes.

RESULTS

Individual participant-level data were analysed from 980 793 adults. During 9·8 million person-years of follow-up, among participants aged between 35 and 89 years, 19 686 (25·6%) of 76 965 deaths were attributed to occlusive vascular disease. After controlling for major vascular risk factors, diabetes roughly doubled occlusive vascular mortality risk among men (death rate ratio [RR] 2·10, 95% CI 1·97-2·24) and tripled risk among women (3·00, 2·71-3·33; χ2 test for heterogeneity p<0·0001). For both sexes combined, the occlusive vascular death RRs were higher in younger individuals (aged 35-59 years: 2·60, 2·30-2·94) than in older individuals (aged 70-89 years: 2·01, 1·85-2·19; p=0·0001 for trend across age groups), and, across age groups, the death RRs were higher among women than among men. Therefore, women aged 35-59 years had the highest death RR across all age and sex groups (5·55, 4·15-7·44). However, since underlying confounder-adjusted occlusive vascular mortality rates at any age were higher in men than in women, the adjusted absolute excess occlusive vascular mortality associated with diabetes was similar for men and women. At ages 35-59 years, the excess absolute risk was 0·05% (95% CI 0·03-0·07) per year in women compared with 0·08% (0·05-0·10) per year in men; the corresponding excess at ages 70-89 years was 1·08% (0·84-1·32) per year in women and 0·91% (0·77-1·05) per year in men. Total cholesterol, blood pressure, and BMI each showed continuous log-linear associations with occlusive vascular mortality that were similar among individuals with and without diabetes across both sexes.

INTERPRETATION

Independent of other major vascular risk factors, diabetes substantially increased vascular risk in both men and women. Lifestyle changes to reduce smoking and obesity and use of cost-effective drugs that target major vascular risks (eg, statins and antihypertensive drugs) are important in both men and women with diabetes, but might not reduce the relative excess risk of occlusive vascular disease in women with diabetes, which remains unexplained.

FUNDING

UK Medical Research Council, British Heart Foundation, Cancer Research UK, European Union BIOMED programme, and National Institute on Aging (US National Institutes of Health).

Evaluation of Diarylheptanoid-Terpene Adduct Enantiomers from Alpinia officinarum for Neuroprotective Activities

Two pairs of new diarylheptanoid-monoterpene adduct enantiomers, (±)-alpininoids A and B [(±)-1 and (±)-2], as well as three pairs of new diarylheptanoid-sesquiterpene adduct enantiomers, (±)-alpininoids C-E [(±)-3-(±)-5], together with four known diarylheptanoids (6-9) were isolated from the rhizomes of Alpinia officinarum. Their structures with absolute configurations were elucidated on the basis of comprehensive spectroscopic analyses and computational calculation methods. The skeletons of these cyclohexene-containing hybrid natural products were hypothesized to be generated via a crucial Diels-Alder cycloaddition between the diarylheptanoids (7 and 8) and terpenes, of which 1 represents a new carbon skeleton. All isolated compounds were evaluated for their neuroprotective effects against MPP⁺ (1-methyl-4-phenylpyridinium)-induced cortical neuron injury. At a concentration of 16 μM, (+)-1 significantly increased cell viability when compared with MPP⁺ treatment alone.

Cajanusflavanols A-C, Three Pairs of Flavonostilbene Enantiomers from Cajanus cajan

Three pairs of new flavonostilbene enantiomers, cajanusflavanols A-C (1-3), along with their putative biogenetic precursors 4-6, were isolated from Cajanus cajan. Compound 1 possesses an unprecedented carbon skeleton featuring a unique highly functionalized cyclopenta[1,2,3-de]isobenzopyran-1-one tricyclic core. Compounds 2 and 3 are the first examples of methylene-unit-linked flavonostilbenes. Their structures with absolute configurations were elucidated by spectroscopic analyses, X-ray diffraction, and computational calculations. Compounds 1 and 2 exhibited significant in vitro anti-inflammatory activities.

Direct Visualization and Control of Atomic Mobility at {100} Surfaces of Ceria in the Environmental Transmission Electron Microscope

Ceria is one of the world's most prominent material for applications in heterogeneous catalysis, as catalyst support or catalyst itself. Despite an exhaustive literature on the structure of reactive facets of CeO₂ in line with its catalytic mechanisms, the temporal evolution of the atomic surface structure exposed to realistic redox conditions remains elusive. Here, we provide a direct visualization of the atomic mobility of cerium atoms on {100} surfaces of CeO₂ nanocubes at room temperature in high vacuum, O₂, and CO₂ atmospheres in an environmental transmission electron microscope. Through quantification of the cationic mobility, we demonstrate the control of the surface dynamics under exposure to O₂ and CO₂ atmospheres, providing opportunities for a better understanding of the intimate catalytic mechanisms.

[A cross-sectional survey of receiving no methadone maintenance treatment in HIV infected injecting drug users in Dehong Dai and Jingpo autonomous prefecture, Yunnan province]

Objective: To understand the current status of receiving no methadone maintenance treatment (MMT) and influencing factors in HIV infected injecting drug users (IDUs) in Dehong Dai and Jingpo autonomous prefectures, Yunnan province. Methods: Data of survival of IDUs with AIDS in Dehong were collected from " Chinese National Comprehensive HIV/AIDS and Care Information System" in December, 2014. Results: There were 987 IDUs who should receive MMT, the majority of them were males (94.6%, 934/987), aged 35-44 years (53.0%, 523/987) and farmers (77.2%, 762/987). Among the 987 IDUs, 60.2% (592/987) received no MMT. Multivariate logistic regression analysis showed that being female (OR=2.66, 95%CI: 1.21-5.87), in Jingpo ethnic group (OR=3.05, 95% CI: 1.97-4.71) were the major risk factors for receiving no MMT; not being farmers (OR=0.46, 95%CI: 0.31-0.70), in Dai ethnic group (OR=0.53, 95%CI: 0.36-0.79), diagnosed HIV infection history ≥10 years (OR=0.60, 95%CI: 0.45-0.81) were the major protective factors for receiving no MMT. The reasons for receiving no MMT included long distance journey (289, 48.8%), fear of exposure (124, 20.9%), poor daily medication compliance (59, 10.0%), fear of side effects (47, 7.9%), others (73, 12.3%). Conclusions: The proportion of receiving no MMT in IDUs with AIDS in Dehong was high. Being female and farmer, in Jingpo ethnic group, low educational level, short diagnosed HIV infection history were influencing factors for receiving no MMT. The effective intervention measures should be taken to further improve MMT coverage according to the different characteristics of the patients.

Design and Synthesis of Dimeric Securinine Analogues with Neuritogenic Activities

Neurite outgrowth is crucial during neuronal development and regeneration, and strategies that aim at promoting neuritogenesis are beneficial for reconstructing synaptic connections after neuronal degeneration and injury. Using a bivalent analogue strategy as a successful approach, the current study identifies a series of novel dimeric securinine analogues as potent neurite outgrowth enhancers. Compounds 13, 14, 17-19, and 21-23, with different lengths of carbon chain of N,N-dialkyl substituting diacid amide linker between two securinine molecules at C-15 position, exhibited notable positive effects on both neuronal differentiation and neurite extension of neuronal cells. Compound 14, one of the most active compounds, was used as a representative compound for mechanistic studies. Its action on neurite outgrowth was through phosphorylation/activation of multiple signaling molecules including Ca²⁺/calmodulin-dependent protein kinase II (CaMKII), extracellular signal-regulated kinase (ERK) and Akt. These findings collectively identify a new group of beneficial compounds for neuritogenesis, and may provide insights on drug discovery of neural repair and regeneration.

Technical note: Isolation and characterization of porcine mammary epithelial cells

Within the mammary gland, functional synthesis of milk is performed by its epithelial (alveolar) cells. The availability of a stable mammary epithelial cell line is essential for biochemical studies to elucidate cellular and molecular mechanisms responsible for nutritional regulation of lactation. Therefore, porcine mammary epithelial cells (PMEC) were isolated from mammary glands of a 9-mo-old nonpregnant and nonlactating gilt and cultured to establish a nonimmortalized cell line. These cells were characterized by expression of cytokeratin-18 (an intermediate filament specific for epithelial cells), β-casein (a specific marker for mammary epithelial cells), and α-lactalbumin. In culture, the PMEC doubled in number every 24 h and maintained a cobblestone morphology, typical for cultured epithelial cells, for at least 15 passages. Addition of 0.2 to 2 μg/mL prolactin to culture medium for 3 d induced the production of β-casein and α-lactalbumin by PMEC in a dose-dependent manner. Thus, we have successfully developed a useful PMEC line for future studies of cellular and molecular regulation of milk synthesis by mammary epithelial cells of the sow.

Chlorpyrifos-induced hormesis in insecticide-resistant and -susceptible Plutella xylostella under normal and high temperatures

Hormesis induced by insecticides at the dosage lower than what ostensibly directly causes death on insects was studied. This paper reports the effects of the in vivo application of varied concentrations of chlorpyrifos (CPF) on Plutella xylostella (DBM). The insecticide concentrations applied included 0.000025-2.5 mg l-1, which are far lower than LC1 (7.2 mg l-1), for the CPF-susceptable (Si) DBM, and 250 mg l-1 which is far below LC1 (1286 mg l-1), for the CPF-resistant (Rc) DBM, as well as LC10- and LC50-doses for both strains. Significant hormesis was found with the 'hermetic-CPFs', i.e., 0.0025 mg l-1 for Si DBM and 2.5 mg l-1 for Rc DBM, at the normal or high temperature either in a 24 h or under a long-term treatment. These doses of CPF significantly stimulated the development and increased the fecundity of Si and Rc DBM at 25°C with approximately 23.5-29.8% activity increase on acetylcholinesterase (AChE) and 30.5-91.3% increase on glutathione S-transferases (GSTs) at 25 or 38°C in 4-24 h. The enzymatic activities were significantly reduced by LC50-CPF at 25°C in vivo, but the inhibition was relieved significantly, if the insects were first subjected to a hormetic-CPF pretreatment. It was remarkable that the average rates of enzymatic activity increase were 67.5-76.6% for AChE and 366-546% for GSTs. Consequently, it was concluded that the hormesis on Si and Rc DBM could be induced by CPF doses far below LC1 at normal or high temperature in short- or long-term treatment. These findings might help to improve the current insect control practices in the field.

Two New Oxindole Alkaloid Glycosides from the Leaves of Nauclea officinalis

Two new oxindole alkaloid glycosides, nauclealomide A and (3S,7R)-javaniside, were isolated from the leaves of Nauclea officinalis. Their structures and absolute configurations were elucidated by means of NMR, HRESIMS, X-ray diffraction, acid hydrolysis and quantum chemical CD calculation. Nauclealomide A is a novel monoterpenoid oxindole alkaloid possessing a rare tetrahydro-2H-1,3-oxazine ring.

Two New Oxindole Alkaloid Glycosides from the Leaves of Nauclea officinalis

Two new oxindole alkaloid glycosides, nauclealomide A and (3 S,7 R)-javaniside, were isolated from the leaves of Nauclea officinalis. Their structures and absolute configurations were elucidated by means of NMR, HRESIMS, X-ray diffraction, acid hydrolysis and quantum chemical CD calculation. Nauclealomide A is a novel monoterpenoid oxindole alkaloid possessing a rare tetrahydro-2 H–1,3-oxazine ring.

Securinega alkaloids from the fruits of Flueggea suffruticosa

Phytochemical investigation on the fruits of Flueggea suffruticosa resulted in the isolation of three new Securinega alkaloids, secu'amamine H (1), 15β-methoxy-14,15-dihydrosecurinine (3), and securinol E (7), as well as eight known ones (2, 4-6, and 8-11). Their structures were elucidated by means of spectroscopic techniques (1D and 2D NMR, MS, UV, and IR). The absolute configurations of the new compounds were established by single-crystal X-ray diffraction and CD analyses.

Suffrutines A and B: a pair of Z/E isomeric indolizidine alkaloids from the roots of Flueggea suffruticosa

Suffrutines A (1) and B (2), a pair of novel photochemical Z/E isomeric indolizidine alkaloids, with a unique and highly conjugated C20 skeleton, were isolated from the roots of Flueggea suffruticosa. The structures were elucidated by extensive analysis of NMR spectra and single-crystal X-ray diffraction. The light-induced isomerization and hypothetical biogenetic pathway to 1 and 2, as well as their activity for regulating the morphology of Neuro-2a cells are also discussed.

Chemical constituents from the roots and stems of Erycibe obtusifolia and their in vitro antiviral activity

Three new quinic acid derivatives, 4-O-caffeoyl-3-O-sinapoylquinic acid methyl ester (1), 5-O-caffeoyl-4-O-syringoylquinic acid methyl ester (2), and 4-O-caffeoyl-3-O-syringoylquinic acid methyl ester (3), as well as four new coumarin glycosides, 7-O-(3-O-sinapoyl-β-D-glucopyranosyl)-6-methoxycoumarin (12), 7-O-(6-O-sinapoyl-β-D-glucopyranosyl)-6-methoxycoumarin (13), 7-O-(2-O-sinapoyl-β-D-glucopyranosyl)-6-methoxycoumarin (14), and 7-O-(6-O-syringoyl-β-D-glucopyranosyl)-6-methoxycoumarin (15), together with eight known compounds (4-11) were isolated from the roots and stems of Erycibe obtusifolia. Their structures were elucidated on the basis of spectroscopic analysis and chemical evidence. All the compounds were screened for their in vitro antiviral activity against respiratory syncytial virus with a cytopathic effect reduction assay. Among them, the di-O-caffeoyl quinates 8-11 displayed a potent in vitro anti-respiratory syncytial virus effect.

Morphology variation and optical properties of ZnO nanostructures grown using bio-template

ZnO nanostructures of different morphologies were grown by immersing eggshell membranes into Zn(NO3)2 ethanol solution with different pH values and subsequently sintered at 500 degrees C. Effects of the solution pH value, immersing time and Mg incorporation on the nanostructure morphology and photoluminescence were studied. ZnO nanostructure morphology was very sensitive to pH value of the solution, immersing time and layer of the templates. Different morphologies of nanofibers, nanotubes, hexagonal nanosheets and hexagonal nanosheets with tips were grown. All nanostructures had strong green emission at 520 nm and weak ultraviolet emission at 377 nm. The green emission weakened in the interwoven nanofibers while the ultraviolet emission enhanced in the hexagonal nanosheets. Incorporation of Mg ions in the solution with a pH of 7 would result in combination of the interwoven nanofibers and enhance the green emission greatly. UV emission at 355 nm from ZnMgO alloys was observed in Mg incorporated nanofibers.

Removal of phosphorus and nitrogen from domestic wastewater using a mineralized refuse-based bioreactor

Municipal solid waste used for landfill becomes stabilized, or aged, some years after placement, and can be safely excavated; the term 'mineralized refuse' is used in this study. The adsorptions of phosphorus, and the nitrification of the mineralized refuse and clay, were investigated by batch incubation. The variation of phosphorus adsorption in the mineralized refuse was fitted to the Freundlich adsorption isotherm equation, giving a maximum phosphorus adsorption capacity of 2310 mg kg(-1). Based on the Langmuir isotherm equation, maximum phosphorus adsorption capacity was calculated to be 1976 mg kg(-1), almost twice that of the clay. The equations for both the mineralized refuse and clay were fitted to zero-order kinetics (R2 > 0.98, P < 0.01, n = 11), giving concentrations of phosphorus as phosphates less than 250 mg L(-1). The K value for the mineralized refuse was about 3.5 times higher than for the clay. The production of nitrogen as nitrates in both the mineralized refuse and the clay after 120 h incubation yielded a first-order reaction kinetics value of 100 mg kg(-1) NH4(+)-N from the initial concentration. The calculated net nitrification as nitrates for the mineralized refuse was 6.3 times higher than for the clay. Domestic wastewater was then treated in a mineralized refuse-based bioreactor for 30 days. The removal rates of COD(cr), total nitrogen and total phosphorus were 73.77 +/- 8.10%, 61.01 +/- 6.75%, and 69.14 +/- 9.25%, respectively. Large accumulations of nitrates occurred in the mineralized refuse-based bioreactor. For the full-scale design, a high column of mineralized refuse is recommended for the denitrification.

Stability and nonlinear optical properties of ZnO nanoparticles

Photoluminescence (PL) of ZnO nanoparticles of different surface states and sizes grown by several methods has been measured. The origin of luminescence and dependence of the luminescence spectrum shape and intensity on 325 nm excitation laser power are studied. Strong ultraviolet emission at 3.26 eV, weak violet emission around 3.12 eV and weak green emission at 2.40 eV have been observed in 16 nm nanoparticles capped by octylamine grown by non-hydrolytic method. The nanoparticles are stable under high power laser radiation and their PL intensity increases nonlinearly with an increasing laser power. As the nanoparticle size decreases to 12 nm, high power laser produces nonradiative centers which may quench the luminescence in a degree. Nanoparticles of 8 nm capped by PVP and uncapped nanoparticles of 14 nm are unstable and their luminescence depends on the excitation laser power. High power laser can quench O vacancy emission and enhance ultraviolet emission in PVP capped nanoparticles while vacancy emission can not be quenched in uncapped nanoparticles.

Growth and properties of ZnO/Zn(1-x)MgxO core/shell nanoparticles

ZnO/Zn(0.9)Mg(0.1)O core/shell nanoparticles have been grown by employing metal cupferronate complex as precursors in organic solvents. ZnO cores are grown by quickly injecting their precursor at 250 degrees C while the shells are performed by slowly injecting their precursors at different temperatures. The grown nanoparticles are characterized by X-ray diffraction, photoluminescence microscopy, and transmission electron microscopy. The effects of the shell growth temperatures and precursor injecting rate are studied. Zn(0.9)Mg(0.1)O shells can epitaxially grow on ZnO cores when the shell growth temperature is lowered to 200 degrees C and the shell precursor is supplied slowly at a rate of 0.1 mmol/h. Increaseing shell supply rate or shell growth temperature results in homogenous growth of Zn(0.9)Mg(0.1)O nanoparticles. The shell growth can dramatically enhance core emission and cause a red shift on the core band edge emission.

Growth and properties of Zn(1-x)CdxO and Zn(1-x)CdxO/ZnO core/shell nanoparticles

Octylamine capped Zn(1-x)CdxO alloys and Zn(1-x)CdxO/ZnO core/shell nanoparticles have been grown by the thermal decomposing of zinc and cadmium cupferronates in organic solvents. Zn(1-x)CdxO alloys incorprated with different concentration of Cd have been grown by quickly injecting of their precursors at 200 degrees C. Zn(1-x)CdxO/ZnO core/shell nanoparticles are performed by slowly injecting of shell precursors at 180 degrees C. The prepared nanoparticles are characterized by X-ray diffraction, absorption spectrometer, Mirco-Raman spectrometer and transmission electron microscopy. The band gap of ZnCdO alloys shrinks linearly and the crystal lattice expands with an increase of Cd concentration. The growth of ZnO shells on ZnCdO cores enhances the core luminescence dramatically and results in a red shift in the absorption and emission of Zn(1-x)CdxO cores.

Polycomb protein EZH2 regulates E2F1-dependent apoptosis through epigenetically modulating Bim expression

Deregulation of the pRB/E2F pathway, which occurs frequently in human malignancy, is often associated with inappropriate proliferation and/or apoptosis. While the role of E2F1 in apoptosis induction has been well-established, it remains unclear how this pro-apoptotic activity is regulated in cancer. Here we describe EZH2, an oncogenic polycomb histone methyltransferase and an E2F1 target, as an important regulator of E2F1-dependent apoptosis. We show that E2F1 induces EZH2 expression, which in turn antagonizes the induction of E2F1 pro-apoptotic target Bim expression. RNAi-mediated gene depletion of EZH2 enhances E2F1-dependent Bim expression, thereby promoting the pro-apoptotic activity of E2F1. Hence, the concomitant induction of EZH2 and Bim by E2F1 constitutes a fail-safe mechanism to allow tumor cells with aberrant E2F1 activity to evade apoptosis. These findings reveal a novel mechanism by which the apoptotic activity of E2F1 is restrained in human cancer and also provide the first evidence that EZH2 directly regulates apoptotic process in cancer cells.

Optical coherence tomography for noninvasive diagnosis of epithelial cancers

We summarize our recent progress in the development of the optical coherence tomography (OCT) systems suitable for clinical diagnosis and the preliminary results for in vivo diagnosis of epithelial cancers (e.g., bladder cancers). The endoscopic spectral-domain OCT system allows simultaneous, real-time, cross-sectional OCT images of tissue structure and functions (i.e., local Doppler blood flow) of biological tissue for enhanced diagnosis. A new approach to use spectral demodulation of elastic scattering is discussed for potential cancer grading. The transverse and axial resolutions of the OCT scopes are 12 microm and 10 microm, respectively. Results of the preliminary clinical studies show that unlike animal carcinogenesis models, bladder cancers in humans are more complicated in terms of epithelial backscattering changes: some lesions exhibit enhanced backscattering; some show reduced scattering owing to complex surface condition changes such as asperities or invaginations induced by tumorigenesis (e.g., papillary transitional cell cancers). Nevertheless, promising results can be provided by incorporating other diagnostic parameters such as changes in local vasculature and urothelial heterogeneity.

Cloning and sequence analysis of thermostable direct hemolysin-related hemolysin gene of Vibrio parahaemolyticus

OBJECTIVE

To establish a method for cloning thermostable direct hemolysin-related hemolysin (trh) gene of Vibrio parahaemolyticus (Vp).

METHODS

After enrichment by PCR, the trh gene, along with the plasmid DNA of pGEX-3X, was digested with two enzymes followed by linkage of the gene and the plasmid, the product of which was transferred into E.coli DH5alpha. Identification of the recombinant plasmid was performed by means of PCR, digestion and sequence analysis.

RESULTS

A fragment about 600 bp was identified in the PCR product of Vp14-91, which was also seen in the product of PCR and enzyme digestion of the recombinant fragment. Sequence analysis demonstrated a homology of 99.1% between the trh gene and the reference gene available in the GenBank.

CONCLUSION

trh gene has been successfully cloned with its sequence analyzed, which prepares the ground for developing gene probe and protective vaccine against Vp.

Detection of DNA strand breaks, DNA-protein crosslinks, and telomerase activity in nickel-transformed BALB/c-3T3 cells

Although nickel compounds are known carcinogens, the underlying carcinogenic mechanisms are not fully understood. The objective of this research was to determine if the genotoxic lesions of DNA strand breaks and DNA-protein crosslinks are present in nickel-transformed BALB/c-3T3 cells, and to further elucidate the potential carcinogenesis of insoluble and soluble nickel compounds through telomerase activity in nickel-transformed BALB/c-3T3 cell lines. DNA strand breaks, DNA-protein crosslinks and telomerase activity were investigated by single cell gel electrophoresis (comet assay), (125)I-postlabelling techniques, and the TRAP-silver staining assay, respectively. Results showed that both DNA strand breaks and DNA-protein crosslinks were present in nickel-transformed BALB/c-3T3 cells. However, the highest levels of DNA strand breaks and DNA-protein crosslinks were found in insoluble crystalline NiS-transformed cells and high levels of DNA strand breaks and DNA-protein crosslinks were also found in the transformed cells induced by two water-soluble NiCl(2) and NiSO(4) at moderate concentrations of cytotoxicity. These data suggest that these two genetic endpoints are useful biomarkers and are associated with cell transformation and carcinogensis of insoluble and soluble nickel compounds. Also, we found that the crystalline NiS- and NiCl(2)-transformed cells possessed a high telomerase activity. A weak telomerase was found in NiSO(4)-transformed cells. The results seem to indicate that in addition to crystalline NiS, some water-soluble nickel compounds such as NiCl(2) are also highly carcinogenic. These results may partly explain the cell transformation and relative carcinogenic potency of insoluble crystalline NiS, soluble NiCl(2), and NiSO(4).

CEP-1347/KT-7515, an inhibitor of SAPK/JNK pathway activation, promotes survival and blocks multiple events associated with Abeta-induced cortical neuron apoptosis

Although the mechanism of neuronal death in Alzheimer's disease (AD) has yet to be elucidated, a putative role for c-jun in this process has emerged. Thus, it was of interest to delineate signal transduction pathway(s) which regulate the transcriptional activity of c-jun, and relate these to alternate gene inductions and biochemical processes associated with beta-amyloid (Abeta) treatment. In this regard, the survival promoting activity of CEP-1347, an inhibitor of the stress-activated/c-jun N-terminal (SAPK/JNK) kinase pathway, was evaluated against Abeta-induced cortical neuron death in vitro. Moreover, CEP-1347 was used as a pharmacologic probe to associate multiple biochemical events with Abeta-induced activation of the SAPK/JNK pathway. CEP-1347 promoted survival and blocked Abeta-induced activation of JNK kinase (MKK4, also known as MEK-4, JNKK and SEK1) as well as other downstream events associated with JNK pathway activation. CEP-1347 also blocked Abeta-induction of cyclin D1 and DP5 genes and blocked Abeta-induced increases in cytoplasmic cytochrome c, caspase 3-like activity and calpain activation. The critical time window for cell death blockade by CEP-1347 resided within the peak of Abeta-induced MKK4 activation, thus defining this point as the most upstream event correlated to its survival-promoting activity. Together, these data link the SAPK/JNK pathway and multiple biochemical events associated with Abeta-induced neuronal death and further delineate the point of CEP-1347 interception within this signal transduction cascade.

Diagnostic yield of repeated smear microscopy examinations among patients suspected of pulmonary TB in Shandong province of China

OBJECTIVES

To analyse the yield of five repeated smear microscopy examinations for the diagnosis of smear-positive pulmonary tuberculosis (TB).

METHODS

Patients with respiratory symptoms and abnormal chest X-rays provided five spontaneous sputum samples for acid-fast bacilli (AFB) smear microscopy in one of nine county laboratories.

RESULTS

Of 9302 patients with respiratory symptoms and abnormal X-rays, 6437 (69%) had at least one smear-positive sputum. Of these, 84.5% were diagnosed on the first smear, 96.7% on the first two smears, and 99.9% on the first three sputum smears. The fourth and fifth sputum smears yielded only seven additional cases (0.1%).

CONCLUSIONS

Smear microscopy examination of two spontaneous sputum specimens is the most efficient, and three sputum smear examinations provide a diagnosis in almost all cases.

[Study on taxol release in the two-liquid-phase cultures of Taxus cuspidata]

Effects of rare earth compound (ammonium sulphate), organic solvents(oleic acid and dibutylphthalate) and the integrated function of the rare earth compound and organic solvents were studied on taxol release in the Taxus cuspidata suspension cultures. And then effects of different organic solvents(paraffin, organic acid, alcohol and ester), their volumetric fraction and phase toxicity were studied on taxol release in the two-liquid-phase cultures of Taxus cuspidata. The results showed that the addition of the rare earth compound or the organic solvents could strengthen obviously taxol release, especially the organic solvents. But the addition of the rare earth compound could not strengthen further taxol release in the twoliquid-phase cultures of Taxus cuspidata. Therefore the organic solvents were very good permeabilizing reagents, which could enhance obviously secondary metabolite in the twoliquid-phase cultures of plant cells. Release percentage of taxol was increased into more than 75% from 40% of the control.

Promotive effect of diethylstilbestrol on urethan-induced mouse lung tumorigenesis

The effect of diethylstilbestrol (DES) on urethan-induced mouse lung tumorigenesis was assessed by a single intraperitoneal injecting of urethan (50 mg/kg) or/and multi intramuscular injecting of DES (5 or 50 mg/kg). All mice were sacrificed 18 weeks after administration, and the lung tumors were examined histopathologically. DES did not produce an elevated lung tumor response when administered alone, but it produced a statistically significant enhancement of incidence of tumors, average number of tumors, incidence of cancers and constituent ratio of malignant tumors when given in conjunction with urethan. The results indicated that DES may be a promoter in lung tumor formation.

Effects of metabolites of benzo(a)pyrene on unschedule DNA synthesis in BALB/3T3 cell line

In order to explore the damage from metabolites of benzo(a)pyrene on DNA of mammalian cells, the effects of four metabolites of benzo(a)pyrene (anti-BPDE, syn-BPDE, 3-OH-BP and 9-OH-BP) on synthesis of DNA and unschedule DNA synthesis (UDS) in BALB/3T3 cells were assayed, by methods of single-labeling and double-labeling. The results showed that all of the four agents were able to increase the synthesis of DNA, but only three of them (apart from syn-BPDE) induced UDS in BALB/3T3 cells. The above indicates that the metabolites of benzo(a)pyrene are able to damage DNA in BALB/3T3 cells, and that this effect may be relative to the sterical structure of metabolites of benzo(a)pyrene.

Absorptance behavior of optical coatings for high-average-power laser applications

A modified photothermal deformation technique is used to measure the absorptance behaviors of optical multilayered dielectric coatings for a high-power laser system. The surface thermal-lensing modification uses an enlarged probe beam to facilitate alignment of the laser beam and data acquisition. The coatings, both reflective and transmissive types, are made by a physical vapor-deposition process. Coating absorptances are observed to depend on the laser's exposure time and power density. Time-dependent absorptance defect models are proposed. Also, micrometer-sized sites of high absorptance and an area with physical damage can be found during the spatial scans. It is proposed that absorptance values reported for coatings in high-repetition-rate or cw-laser systems include time- and power-dependent behaviors in addition to other relevant irradiation parameters.

Immune responses in the epididymis: implications for immunocontraception

In recent years the need to develop vaccines against a variety of sexually transmitted diseases, the desire to treat male infertility and interest in developing alternative contraceptive methods have focused research interest on the immunology of the male reproductive tract. This paper reviews the current state of knowledge of immunity in the male tract. Both physical and immune mechanisms that operate to maintain the blood-testis barrier are discussed with regard to (i) their importance in preventing autoimmune responses against spermatozoa and (ii) how these can be overcome to induce specific immunity in the testis and efferent ducts. The role of both the systemic and mucosal arms of the humoral immune response are discussed both in terms of immune-mediated infertility and the induction of specific immunity. Finally some novel approaches to elicit immunity in the male reproductive tract are discussed.

Renal Vein Thrombosis and Selective Arterial or Venous Thrombolytic Therapy

Background: Renal vein thrombosis (RVT) complicating the nephrotic syndrome is associated with a poor prognosis. Methods/Results: RVT was diagnosed in 12 of 60 patients with a diagnosis of nephrotic syndrome suggested by computed tomography (CT) and subsequently confirmed by selective renal angiography. Fifty patients carried a diagnosis of primary glomerulonephritis with various pathological findings, and 10 patients had lupus nephritis. Renal vein and peripheral vein blood samples were collected in the 12 patients with RVT and were assayed for fibrin(ogen) degradation products (FDP), antithrombin III (AT III), VIIIR:AG, and fibrinogen. The results suggested a state of hypercoagulation. Of these 12 patients, 7 were given 200,000 units of urokinase (UK) over 60 minutes in divided doses selectively via the renal vein. Five patients were given 200,000 units UK selectively into the renal artery. All patients also received 2.5 mg/day warfarin and 75 mg/day persantine. Except for three patients with focal glomerulosclerosis, all patients received 40 mg/day prednisone. After 1 month, the CT scan and blood samples for FDP, AT III, VIIIR:AG, and fibrinogen were repeated. Patients receiving intra-arterial UK had complete resolution of their thrombi. Complete resolution was also suggested in 2 of the 7 patients receiving UK by renal vein, and there was partial resolution in the other five. The hyper-coagulation state decreased in all patients. Conclusions: We conclude that RVT is not an uncommon event in patients with nephrotic syndrome. The diagnosis can be supported reliably using abdominal CT scanning. Although a small number of patients were included in this nonrandomized study, it appeared that intra-arterial thrombolytic therapy yielded better results. The patients with minimal change disease have a good prognosis.

An animal model of septicemia-induced hypercatabolic acute renal failure

A rat model of hypercatabolic acute renal failure (ARF) was developed in order to further investigate the mechanism of this condition. Sprague Dawley rats were separated into three groups: a septicemic group, an ischemic ARF group, and a hypercatabolic ARF group. Septicemia was produced by the i.p. injection of 1 x 10(7) colony-forming units/mL of Escherichia coli. Ischemic ARF was induced by 60 minutes clamping of the left renal artery following a contralateral nephrectomy. Hypercatabolic ARF was produced by combining ischemic ARF with the i.p. injection of 1 x 10(7) colony-forming units/mL of Escherichia coli. The hypercatabolic ARF group exhibited septic clinical features after the surgical procedures. The blood urea nitrogen and the serum creatinine, potassium and carbon dioxide combining power of hypercatabolic ARF were significantly higher than other two groups 24 hours after surgery. In addition, the rats wit hypercatabolic ARF had a greater loss of body weight and a higher mortality rate compared to the other two groups. The features of this form of experimental ARF are similar to the clinical characteristics of hypercatabolic ARF. Consequently, this appears to be a useful model of hypercatabolic ARF.

Study on nutritional status of maintenance hemodialysis patients

The nutritional status of 75 maintenance hemodialysis (MHD) patients was evaluated according to the dietary intake analysis, anthropometric measurements, biochemical and immunological parameters in this study. Furthermore, some possible factors which would affect nutritional status of hemodialysis patients were discussed. The results showed that hemodialysis patients demonstrated a high incidence of malnutrition. The low intake of protein and calorie, metabolic acidosis and inadequate dialysis would worsen the malnutrition while erythropoietin treatment improve the nutritional status of hemodialysis patients. Based on these results, suggestions were proposed for the improvement of nutritional status of MHD.