Total synthesis and stereochemical reassignment of tasiamide B

The first total synthesis of tasiamide B, an octapeptide bearing 4‐amino‐3‐hydroxy‐5‐phenylpentanoic acid unit isolated from the marine cyanobacteria Symploca sp. is described. A simple and efficient way was found to avoid the pyroglutamylation of N^α‐Me‐Gln and led to a reassignment of the N^α‐Me‐L ‐Phe of tasiamide B to be N^α‐Me‐D ‐Phe, which was also supported by 1D and 2D NMR. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd.     

Sunlight triggers cutaneous lupus through a CSF-1-dependent mechanism in MRL-Fas(lpr) mice

Sunlight (UVB) triggers cutaneous lupus erythematosus (CLE) and systemic lupus through an unknown mechanism. We tested the hypothesis that UVB triggers CLE through a CSF-1-dependent, macrophage (M?)-mediated mechanism in MRL-Fas(lpr) mice. By constructing mutant MRL-Fas(lpr) strains expressing varying levels of CSF-1 (high, intermediate, none), and use of an ex vivo gene transfer to deliver CSF-1 intradermally, we determined that CSF-1 induces CLE in lupus-susceptible MRL-Fas(lpr) mice, but not in lupus-resistant BALB/c mice. UVB incites an increase in M?s, apoptosis in the skin, and CLE in MRL-Fas(lpr), but not in CSF-1-deficient MRL-Fas(lpr) mice. Furthermore, UVB did not induce CLE in BALB/c mice. Probing further, UVB stimulates CSF-1 expression by keratinocytes leading to recruitment and activation of M?s that, in turn, release mediators, which induce apoptosis in keratinocytes. Thus, sunlight triggers a CSF-1-dependent, M?-mediated destructive inflammation in the skin leading to CLE in lupus-susceptible MRL-Fas(lpr) but not lupus-resistant BALB/c mice. Taken together, CSF-1 is envisioned as the match and lupus susceptibility as the tinder leading to CLE.     

Consumption of Meals Prepared at Home and Risk of Type 2 Diabetes: An Analysis of Two Prospective Cohort Studies

BackgroundThere has been a trend towards increased dining out in many countries. Consuming food prepared out of the home has been linked to poor diet quality, weight gain, and diabetes risk, but whether having meals prepared at home (MPAH) is associated with risk of type 2 diabetes (T2D) remains unknown.ConclusionsIn two large prospective cohort studies, frequent consumption of MPAH is associated with a lower risk of developing T2D, and this association is partly attributable to less weight gain linked with this dining behavior.     

口腔及肠道菌群与冠心病关系的研究进展

冠心病是由多种病理因素引起的复杂疾病,严重威胁人类健康,其机制尚未完全阐明。近年来,研究表明冠心病与口腔和肠道菌群密切相关。菌群失调导致的炎症反应、氧化应激反应、脂质代谢失调和氧化三甲胺累积是参与冠心病发生的主要风险因素。此外,口腔菌群与肠道菌群相关,参与冠心病的发生与发展。中医治疗疾病的优势在于辨证论治,而证型的判断缺乏客观标准。多项研究应用口腔菌群或肠道菌群分析了疾病的中医证型。本文系统地阐述了口腔菌群和肠道菌群在冠心病发病机制中的作用,阐述了不同中医证型冠心病菌群分析的研究进展,为临床开展此类研究提供参考。     

cDNA cloning and expression analysis of the juvenile hormone acid methyltransferase from seabuckthorn carpenterworm,Holcocerus hippophaecolus (Lepidoptera: Cossidae)

In this study, we report the cDNA cloning and sequence determination of Hh‐JHAMT from the seabuckthorn carpenterworm, Holcocerus hippophaecolus, by using rapid amplification of cDNA ends. The full‐length cDNA of putative Hh‐JHAMT was 1659 bp and contained a highly conserved Motif I, SAM motif I, which showed that Hh‐JHAMT like enzyme was a member of SAM‐dependent MTases. Moreover, putative Hh‐JHAMT had high homology to the other members of the JHAMT peptide family: 59% with Spodoptera litura, 54% with Bombyx mori and 54% with Helicoverpa armigera. Multiple alignments and phylogenetic analysis revealed that Hh‐JHAMT was closely related to JHAMT from Lepidoptera. Real‐time quantitative PCR experiments showed that Hh‐JHAMT mRNA expression was highest in the corpora allata (CA) complex, and was also detected at high levels during earlier larval and adult stages. The JHAMT mRNA level gradually declined during larval development, and the lowest amount of expression was observed in the pupal stage, while it increased to a higher level during adult stages. The pattern of Hh‐JHAMT expression was similar to the mode of JH biosynthesis. These results provided information concerning molecular characteristics of Hh‐JHAMT, whose expression profile suggests that the Hh‐JHAMT gene might be changed with larval development, metamorphosis and adult reproduction of the H. hippophaecolus.     

Photobiomodulation therapy for repeated closed head injury in rats

Repeated traumatic brain injury, leads to cumulative neuronal injury and neurological impairments. There are currently no effective treatments to prevent these consequences. Growing interest is building in the use of transcranial photobiomodulation (PBM) therapy to treat traumatic brain injury. Here, we examined PBM in a repeated closed head injury (rCHI) rat model. Rats were administered a total of three closed head injuries, with each injury separated by 5 days. PBM treatment was initiated 2 hours after the first injury and administered daily for a total of 15 days. We found that PBM‐treated rCHI rats had a significant reduction in motor ability, anxiety and cognitive deficits compared to CHI group. PBM group showed an increase of synaptic proteins and surviving neurons, along with a reduction in reactive gliosis and neuronal injury. These findings highlight the complexity of gliosis and neuronal injury following rCHI and suggest that PBM may be a viable treatment option to mitigate these effects and their detrimental consequences.     

安徽省冬小麦施肥现状与肥料利用效率

冬小麦是安徽省重要的粮食作物。合理施肥是冬小麦获得高产的重要措施,明确当前安徽省冬小麦施肥现状和存在的问题对于指导冬小麦科学施肥具有重要意义。本研究以安徽省冬小麦为对象,于2018年对全省冬小麦主产区1591户农户进行调查,调查内容包括肥料品种、肥料用量、施肥方式、种植面积和产量水平。根据调查结果统计分析安徽省冬小麦种植过程中的施肥现状及存在问题,并以全省冬小麦平均产量和平均施肥量为基准,采用Cate-Nelson方法(十字交叉法)评估安徽省冬小麦产量与氮、磷和钾肥施用的关系,以探索安徽省冬小麦进一步增产增效的主要施肥途径。结果表明:安徽省冬小麦平均产量为5185 kg·hm^-2,氮、磷和钾肥平均施用量分别为206、80和78 kg·hm^-2。其中旱茬麦氮、磷和钾肥平均施用水平比稻茬麦分别高14、16和3 kg·hm^-2。总体上,安徽省冬小麦种植中化肥平均用量趋于合理化,但是在施肥方式、养分运筹和肥料品种上还存在不合理现象。Cate-Nelson方法结果表明,全省冬小麦氮、磷、钾肥施用量中,仅有23.8%、21.2%和2...     

Suppression of plant wilt diseases by nonpathogenic Fusarium oxysporum Fo47 combined with actinomycete strains

In order to build integrated strains with superior growth-promoting and disease-suppression effects, the biological control efficacy of Fo47 solid agents combined with actinomycetes strains toward Fusarium oxysporum and Verticillium dahliae were investigated in experiments on watermelon, cotton and eggplant. Five actinomycetes strains were prepared by solid fermentation. The count of viable solid agents, initially with propagules at 10⁷–10¹¹ CFU/g, slowly decreased after being stored one year at room temperature. After being inoculated into sterile soil for 50 days, the viable count of strain Fo47 remained at a stable level. The suppressive effects of Fo47 combined with strain QLP12 on Fusarium wilt on watermelon and cotton, and Verticillium wilt on eggplant, reaching 58.47%, 50.73% and 58.82%, respectively. This was significantly better than the single strain Fo47 alone, and growth of these treated plants and the colonisation rate of Fo47 were increased substantially as well. These results indicate that solid integrated agents with a high viability count and superior stability in soil could increase disease suppression and promote plant growth by synergy with different strains. The increased suppression obtained by Fo47 combined with actinomycete strains was not due to a simple addition of different mechanisms of biocontrol agents. By being intelligently integrated, these combinations increase disease suppression and provide the best biocontrol effect.     

Epidemic Plasmid Carrying bla CTX-M-15 in Klebsiella penumoniae in China

Objective

To investigate the local epidemiology of Klebsiella penumoniae carrying bla _CTX-M-15 in southern China and to characterize the genetic environment of bla _CTX-M-15.

Methods

PCR and DNA sequencing were used to detect and characterize the genetic contexts of bla _CTX-M-15. The clonal relatedness of isolates carrying bla _CTX-M-15 was determined by pulse-field gel electrophoresis. Conjugative plasmids carrying bla _CTX-M-15 were obtained by mating and were further subject to restriction analysis and replicon typing.

Results

A total of 47CTX-M-15 ESBL-producing isolates of K. pneumoniae were collected from nine hospitals in China from October 2007 to October 2008. Isolates were clustered into various clonal groups. The local spread of bla _CTX-M-15 was mainly mediated by one major conjugative plasmid as determined by S1-PFGE and restriction analysis. A 90-kb plasmid belonging to incompatible group FII was the major carrier of bla _CTX-M-15 in K. pneumoniae. Except bla _TEM-1, the resistance genes such as bla _SHV, bla _DHA-1, bla _OXA-1, qnrB, qnrS, aac(3)-II, and aac(6′)-Ib were not found in the plasmid. In the comparing of conjugative gene sequence, it is 100% identical with the plasmid pKF3–94, which was found in K. pneumonia from Zhejiang province of china previously.

Conclusions

bla _CTX-M-15 was prevalent in K. pneumonia of southern China. The dissemination of bla _CTX-M-15 appeared to be due to the horizontal transfer of a 90-kb epidemic plasmid.