Palladium-catalyzed alkylation of unactivated C(sp3)–H bonds with primary alkyl iodides at room temperature: facile synthesis of β-alkyl α-amino acids

Practical synthesis of β-alkyl α-amino acidsviaC(sp³)–H alkylation at room temperature.

Matrine-induced apoptosis of human nasopharyngeal carcinoma cells via in vitro vascular endothelial growth factor-A/extracellular signal-regulated kinase1/2 pathway inactivation

Matrine, a main active extract from Sophora flavescens Ait, has been demonstrated to exert anticancer effects on various cancer cell lines, such as malignant melanoma, breast cancer, and lung cancer. However, it is currently unclear whether matrine could also elicit an inhibitory effect on growth of nasopharyngeal carcinoma (NPC), let alone the possible molecular mechanisms. Therefore, in a previous study, we investigated matrine-induced proliferation inhibition and apoptosis in NPC cells. It was shown that proliferation of human NPC cells (CNE1 and CNE2) was significantly diminished by matrine in a dose- and time-dependent manner, and apoptosis was induced in both 2 NPC cells, particularly in CNE2 cells. Moreover, the increased apoptosis rate in matrine-treated CNE2 cells confirmed the proapoptotic activity of matrine. We further found that matrine treatment dose- and time-dependently reduced the levels of vascular endothelial growth factor-A (VEGF-A), and inactivated extracellular signal-regulated kinase1/2 (ERK1/2), followed by increased expression of downstream target caspase-3. Overall, we conclude that matrine could induce apoptosis of human NPC cells via VEGF-A/ERK1/2 pathway, which supports the potential use of matrine in clinically treating NPC.

Surface characterization and osteoblast response to a functionally graded hydroxyapatite/fluoro-hydroxyapatite/titanium oxide coating on titanium surface by sol-gel method

OBJECTIVES

To improve efficacy of current titanium and its alloys, in bioactivity and speed of osseointegration, of orthopaedic implants.

MATERIALS AND METHODS

A novel triple-layered functional graded coating, consisting of a porous hydroxyapatite (HA) outermost layer, fluoro-HA (FHA) intermediate layer and titanium oxide (TiO2 ) innermost layer, was created on a titanium substrate by a multistep sol-gel method. X-ray diffraction analysis showed TiO2 anatase and apatite crystallization in the coating.

RESULTS

Morphological analysis performed by scanning electron microscopy showed excellent bonding between coating and substrate, with a thickness of ~2 μm. Scratch testing found favourable adhesion strength of the composite coating. In addition, optical microscope images suggested good biocompatibility. Considering thet in vitro cell response, osteoblasts on the coating exhibited higher cell proliferation and ALP activity compared to pure titanium and HA coating, and demonstrated excellent coating bioactivity.

CONCLUSIONS

Current results indicated that the novel TiO2 /FHA/HA coating has promising clinical applications in orthopaedic and dental implantation.

Neither cytochrome P450 family genes nor neuroendocrine factors could independently predict the SSRIs treatment in the Chinese Han population

OBJECTIVE

This study was intended to explore the relationship between the genetic polymorphisms of the 8 single nucleotide polymorphisms (SNPs) at CYP genes, neuroendocrine factors and the response to selective serotonin reuptake inhibitors (SSRIs) in Chinese Han depressive patients.

METHOD

This was a 6-week randomized controlled trial consisting of 290 Chinese Han depressive patients treated with SSRIs. 8 SNPs of CYP450 genes and 7 neuroendocrine factors were detected. Allele and genotype frequencies were compared between responders and non-responders. The relationships between neuroendocrine factors and treatment response were also analyzed.

RESULTS

No significant differences were found in clinical features between 2 groups at the baseline. No statistical correlation was found between either the genotype or allele frequencies of SNPs in CYP1A2, CYP2C19, or CYP2D6 gene and the -efficacy of SSRIs. There were strong linkage disequilibria between rs4986894, rs1853205, and rs12767583 of CYP2C19 genes, and rs2472299, rs2472300 of CYP1A2 genes. No associations were found between the above haplotypes and the antidepressant response. No neuroendocrine factor was a significant predictor for a response to SSRI antidepressants independently. The combination of neuroendocrine factors, however, predicted the response by 76.1%.

CONCLUSION

There were no significant associations between the 6 SNPs of CYP gene polymorphisms and SSRI response. Neither cytochrome P450 family genes nor neuroendocrine factors independently predict the patients' response to the antidepressants separately. A combination of neuroendocrine factors, however, does have the potential to predict the response.

Selective neuronal differentiation of neural stem cells induced by nanosecond microplasma agitation

An essential step for therapeutic and research applications of stem cells is their ability to differentiate into specific cell types. Neuronal cells are of great interest for medical treatment of neurodegenerative diseases and traumatic injuries of central nervous system (CNS), but efforts to produce these cells have been met with only modest success. In an attempt of finding new approaches, atmospheric-pressure room-temperature microplasma jets (MPJs) are shown to effectively direct in vitro differentiation of neural stem cells (NSCs) predominantly into neuronal lineage. Murine neural stem cells (C17.2-NSCs) treated with MPJs exhibit rapid proliferation and differentiation with longer neurites and cell bodies eventually forming neuronal networks. MPJs regulate ~75% of NSCs to differentiate into neurons, which is a higher efficiency compared to common protein- and growth factors-based differentiation. NSCs exposure to quantized and transient (~150 ns) micro-plasma bullets up-regulates expression of different cell lineage markers as β-Tubulin III (for neurons) and O4 (for oligodendrocytes), while the expression of GFAP (for astrocytes) remains unchanged, as evidenced by quantitative PCR, immunofluorescence microscopy and Western Blot assay. It is shown that the plasma-increased nitric oxide (NO) production is a factor in the fate choice and differentiation of NSCs followed by axonal growth. The differentiated NSC cells matured and produced mostly cholinergic and motor neuronal progeny. It is also demonstrated that exposure of primary rat NSCs to the microplasma leads to quite similar differentiation effects. This suggests that the observed effect may potentially be generic and applicable to other types of neural progenitor cells. The application of this new in vitro strategy to selectively differentiate NSCs into neurons represents a step towards reproducible and efficient production of the desired NSC derivatives.

Recruitment of trimeric proliferating cell nuclear antigen by G1-phase cyclin-dependent kinases following DNA damage with platinum-based antitumour agents

BACKGROUND

In cycling tumour cells, the binary cyclin-dependent kinase Cdk4/cyclin D or Cdk2/cyclin E complex is inhibited by p21 following DNA damage to induce G1 cell-cycle arrest. However, it is not known whether other proteins are also recruited within Cdk complexes, or their role, and this was investigated.

METHODS

Ovarian A2780 tumour cells were exposed to the platinum-based antitumour agent 1R,2R-diaminocyclohexane(trans-diacetato)(dichloro)platinum(IV) (DAP), which preferentially induces G1 arrest in a p21-dependent manner. The Cdk complexes were analysed by gel filtration chromatography, immunoblot and mass spectrometry.

RESULTS

The active forms of Cdk4 and Cdk2 complexes in control tumour cells have a molecular size of ~140 kDa, which increased to ~290 kDa when inhibited following G1 checkpoint activation by DAP. Proteomic analysis identified Cdk, cyclin, p21 and proliferating cell nuclear antigen (PCNA) in the inhibited complex, and biochemical studies provided unequivocal evidence that the increase in ~150 kDa of the inhibited complex is consistent with p21-dependent recruitment of PCNA as a trimer, likely bound to three molecules of p21. Although p21 alone was sufficient to inhibit the Cdk complex, PCNA was critical for stabilising p21.

CONCLUSION

G1 Cdk complexes inhibited by p21 also recruit PCNA, which inhibits degradation and, thereby, prolongs activity of p21 within the complex.

Fast energy relaxation of hot carriers near the Dirac point of graphene

We investigate energy relaxation of hot carriers in monolayer and bilayer graphene devices, demonstrating that the relaxation rate increases significantly as the Dirac point is approached from either the conduction or valence band. This counterintuitive behavior appears consistent with ideas of charge puddling under disorder, suggesting that it becomes very difficult to excite carriers out of these localized regions. These results therefore demonstrate how the peculiar properties of graphene extend also to the behavior of its nonequilibrium carriers.

Topographical distribution pattern of cervical intraepithelial neoplasia across the cervix

OBJECTIVE

The distribution of cervical intraepithelial neoplasia (CIN) lesions across the cervix was determined.

METHODS

A total of 575 women whose pathological diagnosis after cervical conization was confirmed as CIN were studied; 146 had low-grade CIN and 429 had high-grade CIN. CIN lesion location on the cervix was recorded using 12-h clock face notation.

RESULTS

In both groups, 12 o'clock was the most common and 2 o'clock the least common lesion location. The most severe lesions were most often located at 8 o'clock and 7 o'clock, in the low- and high-grade groups, respectively. The 2 o'clock site was the least frequent site for the most severe lesion in both groups. Lesions were found more frequently on the posterior lip of the cervix than on the anterior lip, and on the right side of the cervix than on the left side, in both groups.

CONCLUSIONS

The distribution of CIN lesions is not randomly distributed across the cervix. The 12, 8 and 7 o'clock sites, and the posterior lip and right side of the cervix, should be targeted during colposcopy-directed biopsy of patients with CIN lesions as this may improve diagnostic accuracy.

Rasgrp2 regulates the permissiveness of NIH3T3 cells to a herpes simplex virus 1 mutant with inactivated ICP34.5 gene

We have previously reported that mtHSV, a herpes simplex virus 1 (HSV-1) mutant with an inactivated gene for β-galactosidase, can efficiently lyse tumor but not normal cells. However, the mechanism of this selective oncolytic activity is so far unclear. In this study, using the phage display screening we identified the cellular protein binding to HSV-1 mutant (mtHSV) as (Ras guanyl releasing protein 2) Rasgrp2 which regulates the Ras signaling pathway. Rasgrp2 was found to bind directly to purified mtHSV as well as to mtHSV present within infected HeLa cells where it aggregated on the cell membrane. NIH3T3 cells were found nonpermissive to mtHSV but they became permissive following transformation with the Rasgrp2 gene. This effect was linked to the activation of the Ras-PKR signaling pathway. These observations indicate a key role of Rasgrp2 in the mtHSV infection of NIH3T3 cells and are important for the potential use of mtHSV in cancer therapy.

First Report of Powdery Mildew Caused by Leveillula taurica on Cynanchum kashgaricum in China

Cynanchum kashgaricum Liou f., belonging to the family Apocynaceae, is an endemic herbaceous perennial and extremely endangered plant species, only found in the wild in desert regions of Xinjiang, China (3), and is valuable for sand stabilization. In August 2010, a previously unknown and widespread powdery mildew disease was observed on C. kashgaricum growing in the Taklimakan Desert in Xinjiang, China. Disease symptoms included the appearance of a white mycelial coating on the upper surfaces of leaves, while the corresponding abaxial surfaces of infected leaves became chlorotic. As the disease progressed, the infected leaves turned yellow and necrotic. In this survey, the incidence of affected C. kashgaricum plants was 60%. On the basis of microscopic examination, the morphology of the fungus can be described as follows: the primary conidia of the fungus were lanceolate or clavate, with a pointed apex and rounded base, measuring 40.4 to 82.5 × 11.1 to 24.6 μm, with an irregular surface covered by warts; the secondary conidia varied in shape from subcylindrical to cylindrical, with rounded ends, and had lateral borders that were parallel to each other with rounded or truncate bases, measuring 40.5 to 73.5 × 11.2 to 23.9 μm. The ascomata were nearly gregarious and globe-shaped, of dust-colored appearance, and 113 to 267 μm in diameter; they were immersed in dense mycelial tomentum with numerous asci (usually 10 to 18 per ascoma). Numerous, well-developed appendages were present on the lower half of the ascomata; these appendages were irregularly branched and their length was 0.15 to 0.3 times the diameter of the ascomata. The asci were stalked, long or wide ellipsoidal in shape, and 93 to 140 × 27.6 to 52.9 μm. The asci usually contained two ellipsoidal ascospores 24.5 to 49.5 × 18.3 to 29.5 μm. On the basis of morphologic characteristics, the fungus was identified as Leveillula taurica (2). A voucher specimen of the fungus under the identifier HMTU09021 was deposited in the Mycological Herbarium of Tarim University (HMTU). To verify the identity of the fungus, the internal transcribed spacer (ITS) rDNA was amplified and sequenced, and the sequences were deposited as GenBank Accession No. JN861731. Comparison with sequences in the GenBank database revealed that the ITS sequence showed 100% homology with the sequence of L. taurica on Capsicum annuum (Accession No. GQ167201) and Lepidium latifolium (Accession No. AB044349). Thus, the pathogen was identified as L. taurica on the basis of the anamorphic and teleomorphic morphological characters and the ITS sequence. To our knowledge, while L. taurica infection in plants of the family Apocynaceae has been reported around the world (1), in east Asia only a single report of C. glaucum infection in this genus has occurred, in Afghanistan (1). This is the first report of L. taurica infection of C. kashgaricum. Outbreaks of this powdery mildew could not only threaten growth of the endangered plant but also accelerate local ecological deterioration. References: (1) K. Amano. Host Range and Geographical Distribution of the Powdery Mildew Fungi, 2nd ed. Japan Scientific Societies Press, Tokyo, Japan, 1986. (2) U. Braun. A Monograph of the Erysiphales (Powdery Mildews). Nova Hedwigia Beiheft 89:1, 1987. (3) F. Ying et al. Acta Bot. Boreali-Occidentalia Sin. 23:263, 2003.

Decolourization of the azo dye Orange G in aqueous solution via a heterogeneous Fenton-like reaction catalysed by goethite

Decolourization of the azo dye Orange G (OG) was investigated by using goethite/H2O2 as a heterogeneous Fenton-like reagent. Five principle operational parameters, namely pH, ion strength, concentrations ofgoethite (alpha-FeOOH) and hydrogen peroxide (H2O2), and reaction temperature, were taken into account to investigate how these controlling factors mediated OG decolourization. Goethite surfaces catalysed a Fenton-like reaction responsible for decolourizing OG following pseudo-first-order kinetics (R2 > 0.964). This process was effective but seriously impacted by the medium pH and the dosages of both alpha-FeOOH and H2O2. The decolourization efficiencies of OG increased with the decrease of solution pH and NaCl (chloride ion) concentration and/or the increase of H2O2. The acidic aqueous medium conditions were likely favourable due to the surface adsorption of the negatively charged OG leading to the promotion of decolourizing OG. The apparent activation energy (E) for this reaction was 42.18 kJ mol(-1), a relatively low value. This is consistent with the OG decolourization being enhanced with the reaction temperature increase.

Development and use of EST-SSR markers for assessing genetic diversity in the brown planthopper (Nilaparvata lugens Stål)

To assess genetic diversity in populations of the brown planthopper (Nilaparvata lugens Stål) (Homoptera: Delphacidae), we have developed and applied microsatellite, or simple sequence repeat (SSR), markers from expressed sequence tags (ESTs). We found that the brown planthopper clusters of ESTs were rich in SSRs with unique frequencies and distributions of SSR motifs. Three hundred and fifty-one EST-SSR markers were developed and yielded clear bands from samples of four brown planthopper populations. High cross-species transferability of these markers was detected in the closely related planthopper N. muiri. The newly developed EST-SSR markers provided sufficient resolution to distinguish within and among biotypes. Analyses based on SSR data revealed host resistance-based genetic differentiation among different brown planthopper populations; the genetic diversity of populations feeding on susceptible rice varieties was lower than that of populations feeding on resistant rice varieties. This is the first large-scale development of brown planthopper SSR markers, which will be useful for future molecular genetics and genomics studies of this serious agricultural pest.

Pyrosequencing the midgut transcriptome of the brown planthopper, Nilaparvata lugens

The brown planthopper, Nilaparvata lugens, is a serious pest threatening rice production across the world. To identify the main features of the gene expression and the key components of the midgut of N. lugens responsible for nutrition, xenobiotic metabolism and the immune response, we used pyrosequencing to sample the transcriptome. More than 190,000 clean sequences were generated, which led to about 30,000 unique sequences. Sequence analysis indicated that genes with abundant transcripts in the midgut of N. lugens were mainly sugar hydrolyases and transporters, proteases and detoxification-related proteins. Based on the sequence information, we cloned the candidate sucrase gene; this enzyme is likely to interact with the perimicrovillar membrane through its highly hydrophobic C-terminal region. Many proteases were identified, which supported the hypothesis that N. lugens uses the proteolysis system for digestion. Scores of detoxification genes were newly identified, including cytochrome P450s, glutathione S-transferases, caroxylesterases. A wealth of new transcripts possibly participating in the immune response were described as well. The gene encoding a peptidoglycan recognition protein was cloned. Unlike in Acyrthosiphon pisum, the immunodeficiency pathway may be present in N. lugens. This is the first global analysis of midgut transcriptome from N. lugens.

Reliability analysis of the resting state can sensitively and specifically identify the presence of Parkinson disease

Parkinson disease (PD) is characterized by a number of motor and behavioral abnormalities that could be considered deficits of a "no task" or "resting" state, including resting motor findings and defects in emerging from a resting state (e.g., resting tremor, elevated resting tone, abulia, akinesia, apathy). PET imaging, and recently, the MRI technique of continuous arterial spin labeling (CASL) have shown evidence of changes in metabolic patterns in individuals with PD. The purpose of this study was to learn if the presence of PD could be "predicted" based on resting fluctuations of the BOLD signal. Participants were 15 healthy controls, 14 subjects with PD, and 1 subject who presented as a control but later developed PD. The amplitude of the low frequency fluctuation (ALFF) was used as an index of brain activity level in the resting state. Participants with PD using this index showed a reliable decrease in activity in a number of regions, including the supplementary motor cortex, the mesial prefrontal cortex, the right middle frontal gyrus, and the left cerebellum (lobule VII/VIII) as well as increased activity in the right cerebellum (lobule IV/V). Using a cross validation approach we term "Reliability Mapping of Regional Differences" (RMRD) to analyze our sample, we were able to reliably distinguish participants with PD from controls with 92% sensitivity and 87% specificity. Our "pre-diagnostic" subject segregated in our analysis with the PD group. These results suggest that resting fMRI should be considered for development as a biomarker and analytical tool for evaluation of PD.

Sequence variation and genetic diversity in the giant panda

About 336-444 bp mitochondrial D-loop region and tRNA gene were sequenced for 40 individuals of the giant panda which were collected from Mabian, Meigu, Yuexi, Baoxing, Pingwu, Qingchuan, Nanping and Baishuijiang, respectively. 9 haplotypes were found in 21 founders. The results showed that the giant panda has low genetic variations, and that there is no notable genetic isolation among geographical populations. The ancestor of the living giant panda population perhaps appeared in the late Pleistocene, and unfortunately, might have suffered bottleneck attacks. Afterwards, its genetic diversity seemed to recover to some extent.

Apathy, depression, and motor symptoms have distinct and separable resting activity patterns in idiopathic Parkinson disease

Apathy and depression are heterogeneous syndromes with symptoms that overlap clinically. This clinical overlap leads to problems with classification and diagnosis in clinical populations. No functional imaging study has attempted to separate brain regions altered in apathy from those altered in depression in a clinical population. Parkinson disease (PD) is a disorder in which apathy and depression co-exist in a single population. We evaluate the relationship between apathy, depression, and motor severity of disease in PD, focusing on the relationship between these factors and the amplitude of the low frequency fluctuation (ALFF) in the resting state. We first evaluated if the resting ALFF signal is a reliable measure for our clinical question. For this, we develop and introduce a cross validation approach we term the "Regional Mapping of Reliable Differences" (RMRD) method to evaluate reliability of regions of interest deemed "significant" by standard voxel-wise techniques. Using this approach, we show that the apathy score in this sample is best predicted by ALFF signal in the left supplementary motor cortex, the right orbitofrontal cortex, and the right middle frontal cortex, whereas depression score is best predicted by ALFF signal in the right subgenual cingulate. Disease severity was best predicted by ALFF signal in the right putamen. A number of additional regions are also statistically (but not reliably) correlated with our neuropsychological measures and disease severity. Our results support the use of resting fMRI as a means to evaluate neuropsychiatric states and motor disease progression in Parkinson disease, and the clinical and epidemiologic observation that apathy and depression are distinct pathological entities. Our finding that "significance" and "reliability" are dissociated properties of regions of interest identified as significant using standard voxel-wise techniques suggests that including reliability analyses may add useful scientific information in neurobehavioral research.

Somatic cell cryopreservation and protoplast regeneration of important disease-resistant wild riceOryza meyeriana Baill

Oryza meyeriana Baill is one of the three wild rice species found in Chiia.O. mcyeriana possesses valuable characteristics but is reluctant in cell culturein vitro. In a series of experiments, callus with no regeneration ability was induced from young panicle ofO. meyeriana. The callus was subcultured and propagated. Embryogenic cell clones were obtained after cryopreswation. Suspension cultures were established and protoplasts were isolated and regenerated into plants. Results of artificial inoculation ofXanthomonas campestris pv.Oryzae showed that the strong resistance did not change in the regenerated plants. The development of protoplast-to-plant system is an important progress towards utilization ofO. meyeriana via cellular engineering. The experiments demonstrated that cryopreservation of plant calli was a new way to obtain embryogenic cell line.

First Report of Powdery Mildew of Hexinia polydichotoma Caused by Leveillula lactucae-serriolae in China

Hexinia polydichotoma (Ostenf) H.L. Yang (synonym Chondrilla polydichotoma Ostenf.) is an indigenous sand-binding plant that is widely distributed only in the desert regions of Northwest China. During the summer of 2007, severe outbreaks of a previously unknown powdery mildew were observed in the Taklimakan Desert in Xinjiang, China. Almost 95% of the plants surveyed were affected in this area. The upper surfaces of the stem were covered with white mycelia and the corresponding abaxial surfaces of infected leaves were chlorotic. Affected young, green stems also showed extended chlorosis. As the disease progressed, the infected stems turned yellow and necrotic. Heavy infection resulted in death of the plants. The primary conidia of the fungus were lanceolate with apical pointed, rarely cylindrical or subcylindrical with attenuated apex. They measured 53 to 73 × 15 to 21 μm and had a surface with a net of irregular rides and warts. Subcylindrical or subclavate secondary conidia with rounded ends measuring 50 to 77 × 13 to 20 μm were observed. The ascomata are subgregarious to scattered, globose, and 165 to 200 μm in diameter that are immersed in the dense mycelial tomentum. Numerous and well-developed appendages on the lower half of the ascomata are irregularly branched and can be as long as up to the ascomata diameter. The appendages measure 79 to 106 × 5 to 10 μm and are aseptate, thin walled, and smooth. Asci are numerous (usually more than 20 per ascoma), stalked, clavate-ovoid to nearly cylindrical, and contain two spores (rarely one or three). Ascospores are ellipsoid, hyaline, and measure 25 to 35 × 14 to 20 μm. On the basis of these characteristics, the fungus was identified as Leveillula lactucae-serriolae (2). A voucher specimen was deposited in the Herbarium of Martin Luther University, Halle, Germany (Accession No. HAL 2439F). To confirm the identification, the internal transcribed spacer (ITS) rDNA was amplified and sequenced, and deposited in GenBank (Accession No. HQ821500). Comparison with sequences available in the GenBank database revealed that the ITS sequence shares 99% similarity with that of L. lactucaeserriolae on Lactuca serriola from Iran (Accession No. AB044375.1) (1). Thus, the pathogen was identified as L. lactucae-serriolae based on the host plant species, anamorph morphology, and ITS sequence. Pathogenicity was confirmed through inoculation by gently pressing a diseased stem onto the stem of healthy H. polydichotoma plants. Five inoculated plants were kept under a plastic humid chamber, whereas the same number of noninoculated plants served as the control. The plants were placed under natural conditions (25 to 28°C) with 80 to 90% humidity. At 15 days after inoculation, typical symptoms of powdery mildew developed on the inoculated plants. No symptoms were seen on the control plants. To our knowledge, this is the first report of L. lactucaeserriolae in China and the first record of L. lactucae-serriolae on H. polydichotoma in the world ( http://nt.ars-grin.gov/fungaldatabases/index.cfm ). Because the plant is becoming widely cultivated in the Taklimakan Desert for use in sand-binding, the powdery mildew poses a serious threat to desertification control. References: (1) S. A. Khodaparast et al. Mycol Res. 105:909. 2001. (2) S. A. Khodaparast et al. Mycoscience 43:459, 2002.

Antioxidant network expression abrogates oxidative posttranslational modifications in mice

Antioxidant enzymatic pathways form a critical network that detoxifies ROS in response to myocardial stress or injury. Genetic alteration of the expression levels of individual enzymes has yielded mixed results with regard to attenuating in vivo myocardial ischemia-reperfusion injury, an extreme oxidative stress. We hypothesized that overexpression of an antioxidant network (AON) composed of SOD1, SOD3, and glutathione peroxidase (GSHPx)-1 would reduce myocardial ischemia-reperfusion injury by limiting ROS-mediated lipid peroxidation and oxidative posttranslational modification (OPTM) of proteins. Both ex vivo and in vivo myocardial ischemia models were used to evaluate the effect of AON expression. After ischemia-reperfusion injury, infarct size was significantly reduced both ex vivo and in vivo, ROS formation, measured by dihydroethidium staining, was markedly decreased, ROS-mediated lipid peroxidation, measured by malondialdehyde production, was significantly limited, and OPTM of total myocardial proteins, including fatty acid-binding protein and sarco(endo)plasmic reticulum Ca(²+)-ATPase (SERCA)2a, was markedly reduced in AON mice, which overexpress SOD1, SOD3, and GSHPx-1, compared with wild-type mice. These data demonstrate that concomitant SOD1, SOD3, and GSHPX-1 expression confers marked protection against myocardial ischemia-reperfusion injury, reducing ROS, ROS-mediated lipid peroxidation, and OPTM of critical cardiac proteins, including cardiac fatty acid-binding protein and SERCA2a.

Pigeonpea genomics initiative (PGI): an international effort to improve crop productivity of pigeonpea (Cajanus cajan L.)

Pigeonpea (Cajanus cajan), an important food legume crop in the semi-arid regions of the world and the second most important pulse crop in India, has an average crop productivity of 780 kg/ha. The relatively low crop yields may be attributed to non-availability of improved cultivars, poor crop husbandry and exposure to a number of biotic and abiotic stresses in pigeonpea growing regions. Narrow genetic diversity in cultivated germplasm has further hampered the effective utilization of conventional breeding as well as development and utilization of genomic tools, resulting in pigeonpea being often referred to as an 'orphan crop legume'. To enable genomics-assisted breeding in this crop, the pigeonpea genomics initiative (PGI) was initiated in late 2006 with funding from Indian Council of Agricultural Research under the umbrella of Indo-US agricultural knowledge initiative, which was further expanded with financial support from the US National Science Foundation's Plant Genome Research Program and the Generation Challenge Program. As a result of the PGI, the last 3 years have witnessed significant progress in development of both genetic as well as genomic resources in this crop through effective collaborations and coordination of genomics activities across several institutes and countries. For instance, 25 mapping populations segregating for a number of biotic and abiotic stresses have been developed or are under development. An 11X-genome coverage bacterial artificial chromosome (BAC) library comprising of 69,120 clones have been developed of which 50,000 clones were end sequenced to generate 87,590 BAC-end sequences (BESs). About 10,000 expressed sequence tags (ESTs) from Sanger sequencing and ca. 2 million short ESTs by 454/FLX sequencing have been generated. A variety of molecular markers have been developed from BESs, microsatellite or simple sequence repeat (SSR)-enriched libraries and mining of ESTs and genomic amplicon sequencing. Of about 21,000 SSRs identified, 6,698 SSRs are under analysis along with 670 orthologous genes using a GoldenGate SNP (single nucleotide polymorphism) genotyping platform, with large scale SNP discovery using Solexa, a next generation sequencing technology, is in progress. Similarly a diversity array technology array comprising of ca. 15,000 features has been developed. In addition, >600 unique nucleotide binding site (NBS) domain containing members of the NBS-leucine rich repeat disease resistance homologs were cloned in pigeonpea; 960 BACs containing these sequences were identified by filter hybridization, BES physical maps developed using high information content fingerprinting. To enrich the genomic resources further, sequenced soybean genome is being analyzed to establish the anchor points between pigeonpea and soybean genomes. In addition, Solexa sequencing is being used to explore the feasibility of generating whole genome sequence. In summary, the collaborative efforts of several research groups under the umbrella of PGI are making significant progress in improving molecular tools in pigeonpea and should significantly benefit pigeonpea genetics and breeding. As these efforts come to fruition, and expanded (depending on funding), pigeonpea would move from an 'orphan legume crop' to one where genomics-assisted breeding approaches for a sustainable crop improvement are routine.

Effect of synthetic cannabinoid HU210 on memory deficits and neuropathology in Alzheimer's disease mouse model

Cannabinoids have been shown to increase neurogenesis in adult brain, as well as protect neurons from excitotoxicity, calcium influx, inflammation, and ischemia. Recent studies have shown that synthetic cannabinoids can alleviate water maze impairments in rats treated with intracranial amyloid beta protein (Abeta); however it is unknown whether this effect is due to the cannabinoids' anti-inflammatory properties or whether it affects Abeta processing. Here we investigate whether cannabinoids have any effect on Alzheimer's disease in vivo. We found that HU210, a potent synthetic cannabinoid, did not improve water maze performance or a contextual fear conditioning task in an APP23/PS45 double transgenic mouse model of AD. HU210 had no effect on APP processing and Abeta generation, as well as neuritic plaque formation in the brains of AD transgenic mice. Our study showed that synthetic cannabinoid HU210 had no beneficial effects on AD neuropathology and behavioral deficits of AD model mice, which advises caution of such drug's application in AD therapies.

Poly-GLP-1, a novel long-lasting glucagon-like peptide-1 polymer, ameliorates hyperglycaemia by improving insulin sensitivity and increasing pancreatic beta-cell proliferation

AIM

The clinical value of glucagon-like peptide-1 (GLP-1) is restricted because of its short half-life. To overcome this limitation, a new polymer of GLP-1 was developed by prodrug strategy, termed Poly-GLP-1, and its pharmacological properties were investigated.

METHODS

The in vitro release kinetics of GLP-1 from Poly-GLP-1 was analysed by Western blot. Plasma GLP-1 levels following a single administration of Poly-GLP-1 were determined by enzyme-linked immunosorbent assay. The in vitro effects of Poly-GLP-1 were evaluated using isolated pancreatic islets. The acute effects on glycaemic control and food intake were investigated in C57BL/6J mice s.c. administered with Poly-GLP-1. The chronic effects of Poly-GLP-1 on glycaemic control were further assessed in C57BL/6J and db/db mice treated twice daily for 6 weeks.

RESULTS

Pro-GLP-1 dose dependently increased insulin secretion and decreased glucose, but did not exhibit the insulinotropic action in isolated pancreatic islets without plasma. The glucose-lowering actions of Poly-GLP-1 (3 nmol/kg) remained no less than 12 h after a single injection. Poly-GLP-1 caused a durable restoration of glycaemic control, food intake and body weight gain in db/db mice following 6-week administration. The chronic treatment with Poly-GLP-1 improved glucose tolerance and insulin sensitivity and increased beta-cell mass and proliferation in db/db mice. There was little effect on normal mice treated in the same manner.

CONCLUSIONS

Our results indicated that Poly-GLP-1, a novel GLP-1 polymer, has long-lasting and potent effects on glycaemic control in vivo, and these beneficial effects may be because of improvement of insulin sensitivity and promotion of islet growth and function.

The first SSR-based genetic linkage map for cultivated groundnut (Arachis hypogaea L.)

Molecular markers and genetic linkage maps are pre-requisites for molecular breeding in any crop species. In case of peanut or groundnut (Arachis hypogaea L.), an amphidiploid (4X) species, not a single genetic map is, however, available based on a mapping population derived from cultivated genotypes. In order to develop a genetic linkage map for tetraploid cultivated groundnut, a total of 1,145 microsatellite or simple sequence repeat (SSR) markers available in public domain as well as unpublished markers from several sources were screened on two genotypes, TAG 24 and ICGV 86031 that are parents of a recombinant inbred line mapping population. As a result, 144 (12.6%) polymorphic markers were identified and these amplified a total of 150 loci. A total of 135 SSR loci could be mapped into 22 linkage groups (LGs). While six LGs had only two SSR loci, the other LGs contained 3 (LG_AhXV) to 15 (LG_AhVIII) loci. As the mapping population used for developing the genetic map segregates for drought tolerance traits, phenotyping data obtained for transpiration, transpiration efficiency, specific leaf area and SPAD chlorophyll meter reading (SCMR) for 2 years were analyzed together with genotyping data. Although, 2-5 QTLs for each trait mentioned above were identified, the phenotypic variation explained by these QTLs was in the range of 3.5-14.1%. In addition, alignment of two linkage groups (LGs) (LG_AhIII and LG_AhVI) of the developed genetic map was shown with available genetic maps of AA diploid genome of groundnut and Lotus and Medicago. The present study reports the construction of the first genetic map for cultivated groundnut and demonstrates its utility for molecular mapping of QTLs controlling drought tolerance related traits as well as establishing relationships with diploid AA genome of groundnut and model legume genome species. Therefore, the map should be useful for the community for a variety of applications.

Effect of dexamethasone on acute respiratory distress syndrome induced by the H5N1 virus in mice

Glucocorticoids are widely used in the treatment of different inflammatory diseases. The present study was performed to investigate the effect of dexamethasone (DEX) on acute respiratory distress syndrome (ARDS) induced by the H5N1 viral infection in mice. BALB/c mice, 6-8 weeks old, were divided into three groups with 80 mice in each. The infected group and the DEX-treated infected group were inoculated intranasally with 1 x 10(2) 50% mouse infectious dose of A/Chicken/Hebei/108/2002 (H5N1) viruses, with daily intraperitoneal injections of PBS, or 2.5 mg.kg(-1) DEX at days 3-14 post inoculation, respectively. The control group received noninfectious allantoic fluid and a daily intraperitoneal injection of PBS. In H5N1-infected mice, DEX treatment did not improve the mortality (17 out of 20 versus 16 out of 20 deaths in the DEX-treated infected group versus the infected group), and did not alleviate clinical signs, including weight loss, decreased food intake and inactivity. There was no significant amelioration of the hypoxaemia and ARDS-associated pathological changes in DEX-treated infected mice, as assessed by blood gas analysis and histological score. Furthermore, DEX therapy did not inhibit inflammatory cellular infiltration and cytokine release (interleukin-6 and tumour necrosis factor-alpha) in bronchoalveolar lavage fluid induced by the H5N1 infection. In conclusion, dexamethasone treatment (2.5 mg.kg(-1)) from days 3-14 post inoculation has no beneficial effect on acute respiratory distress syndrome caused by the H5N1 infection in mice.

Aldosterone and angiotensin II synergistically stimulate migration in vascular smooth muscle cells through c-Src-regulated redox-sensitive RhoA pathways

OBJECTIVE

Synergistic interactions between aldosterone (Aldo) and angiotensin II (Ang II) have been implicated in vascular inflammation, fibrosis, and remodeling. Molecular mechanisms underlying this are unclear. We tested the hypothesis that c-Src activation, through receptor tyrosine kinase transactivation, is critically involved in synergistic interactions between Aldo and Ang II and that it is upstream of promigratory signaling pathways in vascular smooth muscle cells (VSMCs).

METHODS AND RESULTS

VSMCs from WKY rats were studied. At low concentrations (10(-10) mol/L) Aldo and Ang II alone did not influence c-Src activation, whereas in combination they rapidly increased phosphorylation (P<0.01), an effect blocked by eplerenone (Aldo receptor antagonist) and irbesartan (AT1R blocker). This synergism was attenuated by AG1478 and AG1296 (inhibitors of EGFR and PDGFR, respectively), but not by AG1024 (IGFR inhibitor). Aldo and Ang II costimulation induced c-Src-dependent activation of NAD(P)H oxidase and c-Src-independent activation of ERK1/2 (P<0.05), without effect on ERK5, p38MAPK, or JNK. Aldo/Ang II synergistically activated RhoA/Rho kinase and VSMC migration, effects blocked by PP2, apocynin, and fasudil, inhibitors of c-Src, NADPH oxidase, and Rho kinase, respectively.

CONCLUSIONS

Aldo/Ang II synergistically activate c-Src, an immediate signaling response, through EGFR and PDGFR, but not IGFR transactivation. This is associated with activation of redox-regulated RhoA/Rho kinase, which controls VSMC migration. Although Aldo and Ang II interact to stimulate ERK1/2, such effects are c-Src-independent. These findings indicate differential signaling in Aldo-Ang II crosstalk and highlight the importance of c-Src in redox-sensitive RhoA, but not ERK1/2 signaling. Blockade of Aldo/Ang II may be therapeutically useful in vascular remodeling associated with abnormal VSMC migration.

Topology preserving non-negative matrix factorization for face recognition

In this paper, a novel topology preserving non-negative matrix factorization (TPNMF) method is proposed for face recognition. We derive the TPNMF model from original NMF algorithm by preserving local topology structure. The TPNMF is based on minimizing the constraint gradient distance in the high-dimensional space. Compared with L(2) distance, the gradient distance is able to reveal latent manifold structure of face patterns. By using TPNMF decomposition, the high-dimensional face space is transformed into a local topology preserving subspace for face recognition. In comparison with PCA, LDA, and original NMF, which search only the Euclidean structure of face space, the proposed TPNMF finds an embedding that preserves local topology information, such as edges and texture. Theoretical analysis and derivation given also validate the property of TPNMF. Experimental results on three different databases, containing more than 12,000 face images under varying in lighting, facial expression, and pose, show that the proposed TPNMF approach provides a better representation of face patterns and achieves higher recognition rates than NMF.

Household CO and PM measured as part of a review of China's National Improved Stove Program

In 2001-2003, a team of researchers from the United States and China performed an independent, multidisciplinary review of China's National Improved Stove Program carried out since the 1980s. As part of a 3500-household survey, a subsample of 396 rural households were monitored for particulate matter less than 4 microm (PM(4)) in kitchens and living rooms over 24 h, of which 159 were measured in both summer and winter. Carbon monoxide was measured in a 40% subsample. The results of this indoor air quality (IAQ) component indicate that for nearly all household stove or fuel groupings, PM(4) levels were higher than - and sometimes more than twice as high as - the national PM(10) standard for indoor air (150 microg PM(10)/m(3)). If these results are typical, then a large fraction of China's rural population is now chronically exposed to levels of pollution far higher than those determined by the Chinese government to harm human health. Further, we observed highly diverse fuel usage patterns in these regions in China, supporting the observations in the household survey of multiple stoves being present in many kitchens. Improved stoves resulted in reduced PM(4) from biomass fuel combinations, but still not at levels that meet standards, and little improvement was observed in indoor pollution levels when other unimproved stoves were present in the same kitchen. As many households change fuels according to daily and seasonal factors, resulting in different seasonal concentrations in living rooms and kitchens, assessing health implications from fuel use requires longitudinal evaluation of fuel use and IAQ levels, combined with accurate time-activity information.

PRACTICAL IMPLICATIONS

Leaving aside the difficult issue of enforcement, it is uncertain whether Chinese household IAQ standards represent realistic objectives for current attainment given current patterns of energy consumption in rural China, which rely so heavily on unprocessed solid fuels. Even when used with chimneys, these fuels emit substantial pollution into the household environment. It is probable that low-emission technologies involving gaseous/liquid fuels or high combustion - efficiency biomass stoves need to be promoted in order to achieve these standards for the greater part of the population.

Upregulation of p27 and its inhibition of CDK2/cyclin E activity following DNA damage by a novel platinum agent are dependent on the expression of p21

The cisplatin analogue 1R,2R-diaminocyclohexane(trans-diacetato)(dichloro)platinum^IV (DAP) is a DNA-damaging agent that will be entering clinical trials for its potent cytotoxic effects against cisplatin-resistant tumour cells. This cytotoxicity may reside in its ability to selectively activate G1-phase checkpoint response by inhibiting CDKs via the p53/p21 pathway. We have now evaluated the role of another CDK inhibitor p27 as a contributor to DAP-mediated inhibition of G1-phase CDK2 activity. Our studies in ovarian A2780 tumour cells demonstrate that p27 levels induced by DAP are comparable to or greater than those seen for p21. The induction of p27 is not through a transcriptional mechanism, but rather is due to a four-fold increase in protein stabilisation through a mechanism dependent on p21. Moreover, DAP-induced p21 promoted the selective increase of p27 in the CDK2 complex, but not in CDK4 complex, and this selective increase contributed to inhibition of the CDK2 kinase activity. The inhibited complex contained either p27 or p21, but not both, with the relative levels of cyclin E associated with p27 and p21 indicating that about 25% of the inhibition of CDK2 activity was due to p27 and 75% due to p21. This study provides the first evidence that p27 upregulation is directly attributable to activation of the p53/p21 pathway by a DNA-damaging agent, and promulgates p53/p21/p27 axis as a significant component of checkpoint response.