气相色谱高温液晶固定液的合成和性能研究——Ⅲ.双-(对烷氧基苄叉)-4,4''-二氨基二苯乙烷薛夫碱类液晶

合成了十种文题所述液晶,其通式为: (其中R为CH_3、C_2H_5……C_(10)H_(21)) 测定了它们的元素分析、红外光谱、液晶相态和温度范围。应用为高温液晶固定液,对蒽油的组分分析和蒽、菲的分离,已取得较好结果。     

雄激素受体对从前列腺癌LNCaP细胞分选出的CK5 +CK8 +细胞的作用及其调控机制

目的:探讨雄激素受体（AR）对从前列腺癌LNCaP细胞中分选出的CK5 +CK8 +细胞的作用及其调控机制。 方法:采用流式细胞术从LNCaP细胞中分选CK5 +CK8 +细胞,使用慢病毒载体携带AR基因转入CK5 +CK8 +细胞。实验...     

菟丝子生品及3种炮制品中总黄酮含量的比较研究

目的：建立菟丝子总黄酮含量测定方法,并比较生品及3种炮制品的总黄酮含量。方法：采用紫外分光光度法,以金丝桃苷为对照品,建立菟丝子总黄酮的含量测定方法,并用此方法测定生品及3种炮制品的总黄酮含量。结果：建立了菟丝子总黄酮的含量测定方法,用此方法测定菟丝子生品中的总黄酮含量为1.68%,清炒品为2.26%,酒炙品为2.27%,盐炙品为2.22%。结论：本方法简便、准确,适合于菟丝子总黄酮含量的测定,菟丝子炮制后的总黄酮含量较生品有了显著升高,其中酒炙品升高最多。     

Hepatitis B virus infection contributes to oxidative stress in a population exposed to aflatoxin B1 and high-risk for hepatocellular carcinoma

Biomarkers of hepatitis B virus (HBV) infection, aflatoxin B1 (AFB1) exposure and oxidative stress were detected in 71 hepatocellular carcinoma (HCC) patients and 694 controls from southern China. Plasma level of AFB1-albumin-adducts (AAA) and protein carbonyl content (PCC) were significantly higher in the 71 HCC cases than in any age/gender matched HBV sero-status groups (p<0.001). HCC patients positive for the p53-249 G-T mutation had a marginally higher level of PCC than those negative for the mutation (p=0.077). HBV infection had a prominent influence on the association between AFB1 exposure and oxidative stress biomarkers in the controls. Our study indicates a significant contribution from HBV infection to oxidative stress in a population with AFB1 exposure which might substantially increase risk for HCC in this region.     

Recombinant TFPI-2 enhances macrophage apoptosis through upregulation of Fas/FasL

Tissue factor pathway inhibitor-2 (TFPI-2) is a Kunitz-type serine proteinase inhibitor with inhibitory activity toward activated factor XI, plasma kallikrein, plasmin, certain matrix metalloproteinases, and the tissue factor-activated factor VII complex. In addition, TFPI-2 has other functions such as promoting cell migration and inducing apoptosis. In the present study, we investigated if TFPI-2 induced apoptosis in cultured U937-derived macrophages and the possible signal pathways that involved in the apoptotic process. Apoptotic DNA fragment detection and caspase-3,9 activity measurements indicated that rTFPI-2 promoted U937-derived macrophage apoptosis. Hoechst 33342 assay and flow cytometry further showed that rTFPI-2 induced apoptosis in cultured macrophages in a dose-dependent manner. Because death receptors of the TNF family such as Fas are the best-understood death pathways that recruit Fas-associated death domain (FADD) and procaspase-8 to the receptor in macrophages, we investigated the expression of Fas and its ligand (FasL) and downstream signal caspase-8 by Western blot analysis. The results indicated that the process of apoptosis triggered by rTFPI-2 was, at least in part, actively conducted by U937-derived macrophages possibly through Fas/FasL signal pathway. In brief, rTFPI-2 may have the potential usefulness in inducing macrophages apoptosis, which suggest TFPI-2 might have antiatherogenic effects.     

Liposome formulated with TAT-modified cholesterol for enhancing the brain delivery

Delivery of drugs to the brain is a major challenge due to the presence of the blood-brain barrier (BBB). The cell penetrating peptide TAT, which appears to enter cells with alacrity, can pass through the BBB efficiently. With this in mind, a novel TAT-modified liposome (TAT-LIP) was developed for overcoming the ineffective delivery of normal drug formulation to the brain. Targeting liposomal formulations are always composed of modified phospholipids as an anchor. However, cholesterol, another liposomal component, which was more stable and cheaper, has not been fully investigated as an alternative anchor. In this study, TAT was covalently conjugated with the cholesterol to prepare the liposome. The cellular uptake by brain capillary endothelial cells (BCECs) of rats and the mechanism of TAT-LIP pathway of endocytosis was explored. The blood brain barrier model in vitro was established to evaluate the transendothelial ability crossing the BBB and its transport mechanism. The biodistribution of each formulation was further identified. The results showed that the positive charge of the TAT-LIP played an important role in enhancing its brain delivery. The absorptive endocytosis might be one of the mechanisms of TAT-LIP crossing the BBB. In conclusion, the experimental data in vitro and in vivo indicated that the TAT-LIP was a promising brain drug delivery system due to its high delivery efficiency across the BBB.     

Development and characterization of 27 SNP markers in the <Emphasis Type="Italic">Mauremys mutica</Emphasis> transcriptome

Asian yellow pond turtle (Mauremys mutica) is listed as an endangered species on the IUCN Red List and recorded in the CITES Appendix II. The wild populations of M. mutica are extremely rare in China, while the main living resources are captive populations. The development of the molecular markers is very important for population identification, population conservation and scientific management of M. mutica. In this study, 27 novel SNP markers for M. mutica were discovered and validated. The observed and expected heterozygosities ranged from 0.0361 to 0.9277 and 0.0588 to 0.5004, respectively. Seven loci showed significant deviation from HWE and no significant linkage disequilibrium was found. These markers would be used in genetic studies helping conservation and management of M. mutica.     

Melatonin modulates the GABAergic response in cultured rat hippocampal neurons

In the present study, we investigated the effect of melatonin on the GABA-induced current (I(GABA) and GABAergic miniature inhibitory postsynaptic currents (mIPSCs) in cultured rat hippocampal neurons using the whole-cell patch-clamp technique. We found that melatonin rapidly and reversibly enhanced I(GABA) in a dose-dependent manner, with an EC50 of 949 μM. Melatonin markedly enhanced the peak amplitude of a subsaturating I(GABA) but not that of a saturating I(GABA). Interestingly, melatonin was effective only when GABA and melatonin were applied together. Furthermore, the effect of melatonin on I(GABA) was voltage-independent and did not change the ion selectivity of the GABA(A) receptor. The melatonin enhancement on I(GABA) can not be blocked by luzindole, a melatonin receptor antagonist, indicating that melatonin-induced I(GABA) enhancement was not via activation of its own membrane receptors. However, this enhancement may be mediated via high-affinity benzodiazepine sites as it was inhibited by the classical benzodiazepine antagonist flumazenil, suggesting an allosteric modulation of melatonin by binding to the sites of GABA(A) receptors. In addition, melatonin increased both amplitude and frequency of GABAergic mIPSCs, indicating that melatonin enhances GABAergic inhibitory transmission. Hence, our observation that melatonin has an enhancing effect on the GABAergic system may implicate a potential pathway for the neuroprotective effects of melatonin.     

Chemical Genetics Identifies Small-Molecule Modulators of Neuritogenesis Involving Neuregulin-1/ErbB4 Signaling

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Aberrant Effective Connectivity of the Ventral Putamen in Boys With Attention-Deficit/Hyperactivity Disorder

ObjectiveThe connectivity alterations in the putamen were found in revealing the neural correlates of attention-deficit/hyperactivity disorder (ADHD), but whether the effective connectivity of the putamen is atypical in ADHD remains unclear. Investigating this abnormality contributes to describing the neural circuit of ADHD at the level of macrostructural organization. MethodsData were acquired from thirty-two boys with ADHD and fifty-two matched typically developing controls (TDC) from Peking University (Peking) dataset deposited at the Neuroimaging Informatics Tools and Resources Clearinghouse (NITRC) platform. We examined the effective connectivity of the putamen using Granger causality analysis (GCA) and then determined whether these connections could differentiate ADHD from TDC. ResultsCompared with TDC, the ADHD group showed decreased effective connectivity from the left ventral rostral putamen (VRP) to left calcarine (CAL), right medial part of the superior frontal gyrus, left orbital part of superior frontal gyrus and left middle occipital gyrus (MOG). Increased effective connectivity from the left inferior occipital gyrus and right lingual gyrus to left VRP was also found in ADHD. The result of the classification accuracy showed that 72.3% of participants were correctly classified using support vector machine. Moreover, GCA values from the left VRP to left CAL and left MOG were significantly correlated with hyper/impulsive scores of patients with ADHD. ConclusionThe findings may help extend our understanding of the ADHD-related neural loops.