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Abstract Background Late embryogenesis abundant (LEA) proteins play an important role in dehydration process of seed maturation. The seeds of Panax notoginseng (Burkill) F. H. Chen are typically characterized with the recalcitrance and are highly sensitive to dehydration. However, it is not very well known about the role of LEA proteins in response to dehydration stress in P. notoginseng seeds. We will perform a genome-wide analysis of the LEA gene family and their transcriptional responses to dehydration stress in recalcitrant P. notoginseng seeds. Results In this study, 61 LEA genes were identified from the P. notoginseng genome, and they were renamed as PnoLEA. The PnoLEA genes were classified into seven subfamilies based on the phylogenetic relationships, gene structure and conserved domains. The PnoLEA genes family showed relatively few introns and was highly conserved. Unexpectedly, the LEA_6 subfamily was not found, and the LEA_2 subfamily contained 46 (75.4%) members. Within 19 pairs of fragment duplication events, among them 17 pairs were LEA_2 subfamily. In addition, the expression of the PnoLEA genes was obviously induced under dehydration stress, but the germination rate of P. notoginseng seeds decreased as the dehydration time prolonged. Conclusions We found that the lack of the LEA_6 subfamily, the expansion of the LEA_2 subfamily and low transcriptional levels of most PnoLEA genes might be implicated in the recalcitrant formation of P. notoginseng seeds. LEA proteins are essential in the response to dehydration stress in recalcitrant seeds, but the protective effect of LEA protein is not efficient. These results could improve our understanding of the function of LEA proteins in the response of dehydration stress and their contributions to the formation of seed recalcitrance.

Soil microbial fuel cells (SMFCs) are an innovative device for soil-powered biosensors. However, the traditional SMFC sensors relied on anodic biosensing which might be unstable for long-term and continuous monitoring of toxic pollutants. Here, a carbon-felt-based cathodic SMFC biosensor was developed and applied for soil-powered long-term sensing of heavy metal ions. The SMFC-based biosensor generated output voltage about 400 mV with the external load of 1000 Ω. Upon the injection of metal ions, the voltage of the SMFC was increased sharply and quickly reached a stable output within 2~5 min. The metal ions of Cd2+, Zn2+, Pb2+, or Hg2+ ranging from 0.5 to 30 mg/L could be quantified by using this SMFC biosensor. As the anode was immersed in the deep soil, this SMFC-based biosensor was able to monitor efficiently for four months under repeated metal ions detection without significant decrease on the output voltage. This finding demonstrated the clear potential of the cathodic SMFC biosensor, which can be further implemented as a low-cost self-powered biosensor.

Electroslag casting with parallel fixed-movable dual electrodes is a new method for achieving better quality of castings in complex mold cavities. In this work, a mathematical model, y=kx2+(k+1)x, was established to describe the ideal correlation between the current ratio (y) and the cross-sectional area ratio (x) of the dual electrodes, where k is the filling ratio. Investigation was conducted on the electroslag casting process with dual electrodes of various cross-sectional areas, but at a constant k value. The experimental results indicated that the ideal correlation was obtained at the stable casting stage, and the fitting results were consistent with the experimental results at certain k values. The experimental findings show that better castings can be obtained when the current ratio is greater than 1.536 and the cross-sectional area ratio is greater than 0.5.

INTRODUCTION: X-ray repair cross-complementing protein 3 (XRCC3) is an essential gene involved in the double-strand break repair pathway. Published evidence has shown controversial results about the relationship between XRCC3 Thr241Met polymorphism and clinical outcomes of non-small cell lung cancer (NSCLC) patients receiving platinum-based chemotherapy. METHODS: A systematic review and meta-analysis was performed to evaluate the predictive value of XRCC3 Thr241Met polymorphism on clinical outcomes of advanced NSCLC receiving platinum-based chemotherapy. Response to chemotherapy, overall survival (OS) and progression-free survival (PFS) were analyzed. RESULTS: A number of 11 eligible studies were identified according to the inclusion criteria. Carriers of the variant XRCC3 241Met allele were significantly associated with good response to platinum-based chemotherapy (ThrMet/MetMet vs. ThrThr: OR = 1.509, 95% CI: 1.099-2.072, Pheterogeneity = 0.618). The XRCC3 Thr241Met polymorphism was not associated with OS (MetMet vs. ThrThr, HR = 0.939, 95% CI:0.651-1.356, Pheterogeneity = 0.112) or PFS (MetMet vs. ThrThr, HR = 0.960, 95% CI: 0.539-1.710, Pheterogeneity = 0.198). Additionally, no evidence of publication bias was observed. CONCLUSIONS: This systematic review and meta-analysis shows that carriers of the XRCC3 241Met allele are associated with good response to platinum-based chemotherapy in advanced NSCLC, while the XRCC3 Thr241Met polymorphism is not associated with OS or PFS.

From the roots of Patrinia scabra two new iridoids, 3-methylbutyric acid 7-hydroxy-7-hydroxymethyl-4-(3-methyl-butyryloxymethyl)-6-oxo-1,6,7,7a-tetrahydrocyclopenta[ c ]pyran-1-yl ester ( 1 ) and 6-hydroxy-7-methylhexahydrocyclopenta[ c ]pyran-3-one ( 2 ) have been isolated. Their structures were determined by means of NMR spectra and X-ray crystallographic analysis. [ABSTRACT FROM AUTHOR]

Three pyrrole alkaloids were isolated from Bolbostemma paniculatum . Their structures were elucidated as 4-(2-formyl-5-methoxymethylpyrrol-1-yl)butyric acid methyl ester ( 1 ), 2-(2-formyl-5-methoxymethylpyrrol-1-yl)-3-phenylpropionic acid methyl ester ( 2 ) and α -methyl pyrrole ketone ( 3 ) by spectroscopic techniques. Among them, 1 and 2 are new compounds. [ABSTRACT FROM AUTHOR]

Objective: To study the chemical constituents from Daphne odora var. atrocaulis., Method: The chemical constituents were isolated and repeatedly purified by silica gel column chromatography and the structures were elucidated by the NMR spectra and physicochemical properties., Result: Sixteen compounds were obtained and nine of them were identified as beta-sitosterol, 4-hydroxy ethylbenzoate, (2E),-2-propenoic acid,3-(3,4-dihydroxyphenyl)-decosylester, genkwanin, 2,4-dihydroxypyrimidine, daphnetin, daphnoretin, 5,7,4'-trihydroxyflavone-3ol, daucosterol., Conclusion: Seven compounds were obtained from D. odora var. atrocaulis. for the first time.

Objective: To study the chemical constituents in bark of Larix olgensis var. koreana., Method: The compounds were isolated with silica gel column chromatography and their structures were elucidated on the basis of spectral analysis (IR, EI-MS, 1H-NMR, 13C-NMR)., Result: Eight compounds were isolated and identified as isopimaric acid (I), beta-sitosterol (II), 24R,5alpha-stigmast-3,6-dione (III), larixol (IV), ferulic acid (V), lariciresinol (VI), secroisolariciresinol (VII) and isolariciresinol (VIII)., Conclusion: All the compounds were isolated from this plant for the first time.

Objective: To investigate the chemical constituents of the bulbs of Bolbostemma panicultum., Method: The compounds were isolated by column chromatography on silica gel, C18, Sephadex LH-20 separately and their structures were elucidated by chemical and spectroscopic technologies., Result: Eight compounds were isolated and identified as maltol(I), emodin(II), cucurbitacin B(III), cucurbitacin E(IV), stigmasta-7, 22, 25-triene-3-ol(V), stigmasta-7, 22, 25-triene-3-nonadecanoic acid ester(VI), stigmasta-7, 22, 25-triene-3-O-beta-D-glucopyranoside(VII), stigmasta-7, 22, 25-triene-3-O-beta-D-(6'-palmitoyl) glucopyranoside(VIII)., Conclusion: I-VIII were obtained from this plant for the first time; VI and VIII are new compounds.

Objective: To analyse the effects of buyang huanwu decoction (BYHWT) on differentially expressed genes during cerebral ischemia/reperfusion in rats with DNA microarray., Method: cDNA microarray chips containing 512 cDNAs were made by Biostar Genechip Inc. Sprague-Dawley rats were subjected to 2 h of middle cerebral artery occlusion (MCAO) with an filament. Saline or BYHWT was given p.o. after onset of cerebral ischemia and brains were removed after 24 h of recirculation for mRNAs isolation. A differential measurment of mRNAs from post-ischemic and BYHWT treated animals was performed with microarray., Result: Up-and down-regulated genes were 69 and 80 in ischemic group. Up-and down-regulated genes were 25 and 6 in BYHWT treated group., Conclusion: BYHWT regulates the differential expression genes after focal brain ischemia/reperfusion in rats, due to its mechanism of protecting cerebral ischemia/reperfusion injury.

Aim: To study the lignans from Patrinia scabra Bunge., Methods: The constituents were separated and purified by column chromatography with silical gel, RP-silical gel and Sephadex LH-20. Their structures were identified on the basis of spectral data (IR, MS, 1HNMR, 13CNMR, HMQC and HMBC)., Results and Conclusion: A new lignan was obtained and its structure was elucidated as 4-[1-ethoxyl-1-(4-hydroxy-3-methoxy)benzyl]methyl- 2-(4-hydroxy-3-methoxy)benzyl-3-hydroxymethyl-tetrahydro-furan (2), along with three known lignans, lariciresinol (1), isolariciresinol (3) and nortracheloside (4).