医用有机化学课程中的案例教学

“医用有机化学”是医学院各专业一年级学生的必修课,该课程难度较高,核心内容与临床实践相关性较低,容易使学生产生畏难情绪。我们在教学中通过引入真实临床案例,使学生认识到有机化学知识与临床的相关性,进而激发医学生们对课程学习的热情。

Meta-analysis of tau genetic polymorphism and sporadic progressive supranuclear palsy susceptibility

OBJECTIVE： To quantitatively evaluate the association between tau genetic polymorphism （H1 and H2） and susceptibility to sporadic progressive supranuclear palsy （PSP）. DATA SOURCES： Relevant Medical Subject Heading terms and text words were used to identify articles from MEDLINE （1966/2010-07）, EMBASE （1984/2010-07）, and Chinese National Knowledge Infrastructure （1979/2010）, as well as references of the retrieved articles. STUDY SELECTION： The selected articles met the following criteria： sporadic PSP case group and healthy control group, as well as genotype frequency （H1/H1 and H1/H2 ＋ H2/H2） in cases and controls. Genotype distribution in the control groups was tested using the Hardy-Weinberg Equilibrium （HWE）. Articles irrelevant to HWE were excluded, and a forest plot was performed to combine all selected articles with Review Manager （Version 5.0）. MAIN OUTCOME MEASURES： The summary odds ratios arid corresponding 95% confidence intervals （95%CI） for tau polymorphism （H1/H1 and H1/H2 ＋ H2/H2） between sporadic PSP case and healthy control groups were estimated using the fixed effects model to assess whether tau genetic polymorphism is associated with sporadic PSP susceptibility. RESULTS： According to inclusion and exclusion criteria, a total of 16 articles, which included 1 337 sporadic PSP cases and 2 073 controls, were used in the study. Two articles were excluded because of deviation from HWE in the control groups. The combined result, based on all studies, showed a significant difference in genotype distribution between cases and controls： H1H1 vs. H1H2 ＋ H2H2 （odds ratio （OR） = 4.98, 95%C1： 3.97-6.23, P 〈 0.01）. Stratifying for geographic distribution of PSP, sporadic PSP cases exhibited a significantly higher frequency of H1H1 genotypes than controls in the United States （OR = 4.07, 95%C/： 3.16-5.25, P 〈 0.01） and Europe （OR = 8.60, 95%C1： 5.05-14.64, P〈 0.01）. CONCLUSION： Tau genetic polymorphism is associated with sporadic PSP susceptibility, and geographic distribution might play a role in tau genetic polymorphism and sporadic PSP susceptibility.

Computer-aided molecular design and optimization of potent inhibitors disrupting APC-Asef interaction

Colorectal cancer(CRC)is the second leading cause of cancer mortality worldwide.At initial diagnosis,approximately 20%of patients are diagnosed with metastatic CRC(mCRC).Although the APC-Asef interaction is a well-established target for mCRC therapy,the discovery and development of effective and safe drugs for mCRC patients remains an urgent and challenging endeavor.In this study,we identified a novel structural scaffold based on MAI inhibitors,the first-in-class APC-Asef inhibitors we reported previously.ONIOM model-driven optimizations of the N-terminal cap and experimental evaluations of inhibitory activity were performed,and 24-fold greater potency was obtained with the best inhibitor compared to the parental compound.In addition,the cocrystal structure validated that the two-layerπ-πstacking interactions were essential for inhibitor stabilization in the bound state.Furthermore,in vitro and in vivo studies have demonstrated that novel inhibitors suppressed lung metastasis in CRC by disrupting the APC-Asef interaction.These results provide an intrinsic structural basis to further explore drug-like molecules for APC-Asef-mediated CRC therapy.

Discovery of a potent and highly selective inhibitor of SIRT6 against pancreatic cancer metastasis in vivo

Pancreatic cancer,one of the most aggressive malignancies,has no effective treatment due to the lack of targets and drugs related to tumour metastasis.SIRT6 can promote the migration of pancreatic cancer and could be a potential target for antimetastasis of pancreatic cancer.However,highly selective and potency SIRT6 inhibitor that can be used in vivo is yet to be discovered.Here,we developed a noveSIRT6 allosteric inhibitor,compound 11e,with maximal inhibitory potency and an IC_(50) value of 0.98±0.13μmol/L.Moreover,compound 11e exhibited significant selectivity against other histone deacetylases(HADC1-11 and SIRT1-3)at concentrations up to 100μmol/L.The allosteric site and the molecular mechanism of inhibition were extensively elucidated by cocrystal complex structure and dynamic structural analyses.Importantly,we confirmed the antimetastatic function of such inhibitors in four pancreatic cancer cell lines as well as in two mouse models of pancreatic cancer liver metastasis.To our knowledge,this is the first study to reveal the in vivo effects of SIRT6 inhibitors on liver metastatic pancreatic cancer.It not only provides a promising lead compound for subsequent inhibitor developmentargeting SIRT6 but also provides a potential approach to address the challenge of metastasis in pancreatic cancer.

MiR319-targeted OsTCP21 and OsGAmyb regulate tillering and grain yield in rice

Multiple genes and microRNAs(miRNAs)improve grain yield by promoting tillering.MiR319s are known to regulate several aspects of plant development;however,whether miR319s are essential for tillering regulation remains unclear.Here,we report that miR319 is highly expressed in the basal part of rice plant at different development stages.The miR319 knockdown line Short Tandem Target Mimic 319(STTM319)showed higher tiller bud length in seedlings under low nitrogen(N)condition and higher tiller bud number under high N condition compared with the miR319a-overexpression line.Through targets prediction,we identified OsTCP21 and OsGAmyb as downstream targets of miR319.Moreover,OsTCP21 and OsGAmyb overexpression lines and STTM319 had increased tiller bud length and biomass,whereas both were decreased in OsTCP21 and OsGAmyb knockout lines and OE319a.These data suggest that miR319 regulates rice tiller bud development and tillering through targeting OsTCP21 and OsGAmyb.Notably,the tiller number and grain yield increased in STTM319 and overexpression lines of OsTCP21 and OsGAmyb but decreased in OE319a and knockout lines of OsTCP21 and OsGAmyb.Taken together,our findings indicate that miR319s negatively affect tiller number and grain yield by targeting OsTCP21 and OsGAmyb,revealing a novel function for miR319 in rice.

Targeting a cryptic allosteric site of SIRT6 with small-molecule inhibitors that inhibit the migration of pancreatic cancer cells

SIRT6 belongs to the conserved NAD^(+)-dependent deacetylase superfamily and mediates multiple biological and pathological processes.Targeting SIRT6 by allosteric modulators represents a novel direction for therapeutics,which can overcome the selectivity problem caused by the structural similarity of orthosteric sites among deacetylases.Here,developing a reversed allosteric strategy Allo Reverse,we identified a cryptic allosteric site,Pocket Z,which was only induced by the bi-directional allosteric signal triggered upon orthosteric binding of NAD^(+).Based on Pocket Z,we discovered an SIRT6 allosteric inhibitor named JYQ-42.JYQ-42 selectively targets SIRT6 among other histone deacetylases and effectively inhibits SIRT6 deacetylation,with an IC50 of 2.33μmol/L.JYQ-42 significantly suppresses SIRT6-mediated cancer cell migration and pro-inflammatory cytokine production.JYQ-42,to our knowledge,is the most potent and selective allosteric SIRT6 inhibitor.This study provides a novel strategy for allosteric drug design and will help in the challenging development of therapeutic agents that can selectively bind SIRT6.

Copper-sulfide cluster assembled architecture via in situ reaction

A new copper-thiolate cluster assembled framework[Cu2(μ4-SCH3)Cl]n(1),has been solvothermally synthesized through in situ reaction viz.,in situ ligand generation and metal reduction.Compound 1 represents the first 3 D framework based on Atlas-sphere functionalized by singleμ2-Cl groups.DOS calculation reveals the interaction of electronic structures.It is found that the HOMO is mainly distributed on Cl,Cu and S bonding orbitals,while the LUMO is dominated by Cu-Cl antibonding orbitals.