Picomolar inhibitor of reverse transcriptase featuring significantly improved metabolic stability

Considering the undesirable metabolic stability of our recently identified NNRTI 5 (t1/2 = 96 min) in human liver microsomes, we directed our efforts to improve its metabolic stability by introducing a new favorable hydroxymethyl side chain to the C-5 position of pyrimidine. This strategy provided a series of novel methylol-biphenyl-diarylpyrimidines with excellent anti-HIV-1 activity. The best compound 9g was endowed with remarkably improved metabolic stability in human liver microsomes (t1/2 = 2754 min), which was about 29-fold longer than that of 5 (t1/2 = 96 min). This compound conferred picomolar inhibition of WT HIV-1 (EC50 = 0.9 nmol/L) and low nanomolar activity against five clinically drug-resistant mutant strains. It maintained particularly low cytotoxicity (CC50 = 264 μmol/L) and good selectivity (SI = 256,438). Molecular docking studies revealed that compound 9g exhibited a more stable conformation than 5 due to the newly constructed hydrogen bond of the hydroxymethyl group with E138. Also, compound 9g was characterized by good safety profiles. It displayed no apparent inhibition of CYP enzymes and hERG. The acute toxicity assay did not cause death and pathological damage in mice at a single dose of 2 g/kg. These findings paved the way for the discovery and development of new-generation anti-HIV-1 drugs.

Analysis of heart rate variability in patients with acute stroke / 中国医师进修杂志

[Abstact] Objective To investigate the characteristics of heart rate variability (HRV) of ambulatory electrocardiogram in patients with acute stroke, and evaluate the predictive value of HRV in stroke prognosis. Methods Eighty-three patients acute stroke (study group) and 83 cases of healthy subjects (control group) from October 2016 to October 2017 in Dalian Municipal Central Hospital Affiliated of Dalian Medical University were selected. The 24 h ambulatory electrocardiogram was performed to determine HRV in 2 groups, including standard deviation of NN intervals (SDNN), standard deviation of the 5 min mean cycle lengths (SDANN), root-mean-square successive difference (RMSSD) and percentage value of NN50 count (PNN50). Results The SDNN, SDANN, RMSSD and PNN50 in study group were significantly lower than those in control group: (80.83 ± 10.52) ms vs. (148.11 ± 22.59) ms, (79.98 ± 8.89) ms vs. (129.35 ± 5.34) ms, (19.28 ± 4.25) ms vs. (39.57 ± 2.38) ms and (5.91 ± 2.12) % vs. (19.35 ± 12.15) %, and there were statistical differences (P＜0.05). Among the 83 patients with acute stroke, there were no statistical differences in SDNN, SDANN, RMSSD and PNN50 between ischemic stroke (54 cases) and hemorrhagic stroke (29 cases) (P＞0.05). The SDNN, SDANN, RMSSD and PNN50 in right stroke (43 cases) were significantly lower than those in left stroke (40 cases): (75.18 ± 2.32) ms vs. (88.12 ± 3.58) ms, (73.36 ± 2.18) ms vs. (85.69 ± 7.29) ms, (17.57 ± 1.67) ms vs. (20.58 ± 4.23) ms and (4.39 ± 1.57) % vs. (8.61 ± 1.12) %, and there were statistical differences (P＜0.05). Patients were followed up for 1 year, 24 died and 59 survived. The SDNN, SDANN, RMSSD and PNN50 in dead patients were significantly lower than those in survived patients: (92.35 ± 4.58) ms vs. (154.37 ± 4.65) ms, (76.23 ± 4.03) ms vs. (143.95 ± 4.34) ms, (7.43 ± 2.12) ms vs. (31.65 ± 1.52) ms and (2.35 ± 0.46) % vs. (11.65 ± 0.48) % , and there were statistical differences (P＜0.05). Conclusions The autonomic nervous function of patients with acute stroke is seriously unbalanced, with increased sympathetic excitability and decreased vagus excitability. The decrease of HRV can easily induce cardiac events and seriously affect the prognosis.

Saikosaponin-b regulates the proliferation and apoptosis of HepG2 cells by targeting the MACC1/c-Met/Akt signaling pathway / 中国药理学与毒理学杂志

OBJECTIVE Metastasis-associated in colon cancer-1 (MACC1) is an oncogene that has been newly identified. It promotes tumor proliferation and invasion via the MET pathway. Our study investigated the effects of Saikosaponin-b(SS-b) on the proliferation and apoptosis of HepG2 cells and its regulation on MACC1/c-Met/Akt signaling pathway. METHODS HepG2 cells were treated with SS-b (10-800 g·L-1) for 48 h in vitro. The CCK-8 assay was used to assess cell proliferation, and cell apoptosis was determined by Hoechst33258 staining, AnnexinⅤ/PI staining and caspase 3 assay. RT-PCR was used to examine the expression of MACC1, c- MET and hepatocyte growth factor (HGF) mRNA. MACC1 protein was detected by Western blot and immunohistochemistry. The protein expressions of p-c-MET, c-MET, p-AKT, AKT, p-BAD, BAD were measured by Western blot. RESULTS SS-b inhibited the growth of HepG2 cells in dose-dependent way and induced cell apoptosis significantly. HepG2 cells showed karyopyknosis, fragmentation and fluorescence highlight in SS-b treatment group. FCM results showed that apoptosis rate of HepG2 cells increased with SS- b concentration. The immunofluores?cence results showed that the MACC1 expression decreased significantly in HepG2 cells treated with SS-b. The expression levels of MACC1, c-MET and HGF mRNA in HepG2 cells were significantly inhibited by SS-b. SS-b also significantly decreased the protein expressions of MACC1, p-c-MET and p-AKT while increased the expression of p-BAD and caspase 3 in HepG2 cells(P<0.05). CONCLUSION SS-b inhibited the proliferation and induced the apoptosis of HepG2 cells by targeting the MACC1/c-Met/Akt signaling pathway.

Research advances on microchimerism / 中国实验血液学杂志

The microchimerism is a status of the microcell or DNA of an individual in another one with genetic differences. Taking an overall view about the discovery and research of the microchimerism, it was found that although the study of the microchimerism emphasizes the formation, origin, distribution, type, relationship to disease and several other aspects, the objects of the study are always the microchimerism that obtained naturally. As it is known to all, the microchimerism can also be produced in some clinical treatment, such as in the transplant and transfusion, but compared with the microchimerism gained naturally, obviously, the study for the iatrogenic microchimerism formed in the treatment is not elaborate enough. The curative effect of micro transplantation, a new technique for leukemia treatment, is obvious, but its mechanism is unclear, whether that is related to microchimerism still needs further research. This review summarizes the study history and perspective of the microchimerism so as to provide some ideas for studying the action mechanism of microchimerism in micro transplantation.

Estrogen reduced myocardial damage by regulating Gαs-cAMP pathway in isoprenaline injured rats / 生理学报

The aim of the present study is to explore the mechanism of estrogen on regulating cardiac function disorder by adjusting the stimulating adenylate cyclase G α protein (Gαs)-cycle adenosine monophosphate (cAMP) signal pathway. Adult female rats were randomly divided into five groups: sham group, ovariectomized group (OVX), OVX and 17β-estradiol given group (OVX+E₂), OVX and isoprenaline injected group (OVX+ISO), OVX and 17β-estradiol, isoprenaline injected group (OVX+E₂+ISO). Rats were ovariectomized, and two weeks later, OVX+E₂group was injected with E₂, OVX+ISO group was injected with ISO, OVX+E₂+ISO group was injected with E₂and ISO. Another four weeks later, the hemodynamic parameters were monitored by carotid artery intubation: left ventricular systolic pressure (LVSP), left ventricular end-diastolic pressure (LVEDP), maximal differentials of left ventricular developed pressure (+dp/dt(max)), and minimal differentials of left ventricular developed pressure (-dp/dt(max)). Brain natriuretic peptide (BNP) and cAMP concentration in plasma were determined; Gα(s) protein expression in myocardium was determined. The results showed that the hemodynamic parameters, the concentration of BNP and cAMP in plasma had no significant changes after ovariectomy compared with sham group. But after isoprenaline injection in ovariectomized rats, LVSP and +dp/dt(max) declined (P < 0.01), LVEDP and -dp/dt(max) elevated (P < 0.01); plasma BNP concentration increased (P < 0.01); plasma cAMP concentration decreased (P < 0.01), compared with OVX group. Further estrogen supplements improved the heart function treated by isoprenaline: LVSP and +dp/dt(max) elevated (P < 0.01), LVEDP and -dp/dtmax declined (P < 0.05, P < 0.01); the plasma BNP concentration decreased (P < 0.01); the plasma cAMP concentration increased (P < 0.01). Estrogen had no significant influence on Gαs protein expression. The results suggest that estrogen can alleviate myocardial injury and regulate cardiac function disorder by increasing cAMP level, finally improved the excessive suppression of myocardium.

Evaluation of the value of ultrasound elastography in differential diagnosis of benign and malignant thyroid solid nodules / 中国地方病学杂志

Objective To evaluate the value of ultrasound elastography score and strain ratio index in the differential diagnosis of thyroid solid nodules. Methods Eighty-six thyroid solid nodules of 69 patients were divided into 2 groups based on their pathologic results: benign nodules group and malignant nodules group.Compared with pathological results, each thyroid solid nodules' elastographic scores and strain ratio index were respectively analyzed. The sensitivity, specificity and accuracy of elasticity score and strain ratio index were calctlated.The receiver operator characteristic (ROC) curves were drawn according to the results, to choose the best cut-off value.Results There were 67 nodules in benign nodules group and 19 nodules in malignant nodules group. The diameter of benign nodules was (2.05 ± 0.21)cm, malignant nodules was (1.62 ± 0.12)cm. There were no significant differences in the elasticity score and strain ratio index between benign and malignant nodules(t= - 1.736, P ＞ 0.05). Malignant lesions had a higher score and strain ratio index(median 3, 3.97, respectively) than benign ones(median 2, 1.66,respectively, Z = - 5.290, - 5.450, all P ＜ 0.05). If the cut-off value of the elastographic scores was equal or more than 3, the sensitivity, specificity and accuracy were 84.2%(16/19) ,86.6%(58/67) and 86.0%(74/86), respectively,with an area under ROC curve of 0.854. If the cut-off value of the strain ratio index was equal or more than 2.50,the sensitivity, specificity and accuracy were 89.4%(17/19),86.6%(58/67) and 87.2%(75/86), respectively, with an area under ROC curve of 0.911. Conclusion Elasticity score and strain ratio index are helpful in differentiating benign and malignant lesions of thyroid with high clinical value.

Effect of Qianjin Fubao on changes of behavior and estradiol level in chronic stress model rats / 中国中药杂志

<p><b>OBJECTIVE</b>To investigate the effect of Qianjin Fubao (QJFB) on behavior and estradiol level in femal chronic stress model rats.</p><p><b>METHOD</b>Twenty four female Wistar rats (2 month old) were evenly randomized into normal control, animal model and QJFB (0.7 g x kg(-1) x d(-1)) group. The QIFB group and the stress group were exposed to a chronic unpredictable stress for 21 days. Rats of the QJFB group received perfusion of Qianjin Fubao, and rats of stress and control group were perfused with normal saline. The behavior of three groups were determined with the method of Open-field before and after right stress respectively. Serum level of estradiol was detected with radioim munoassay.</p><p><b>RESULT</b>The behavioral score and the serum level of estradiol of the stressed group were significantly lower than those of the control group after stress (P < 0.05). There were no significant differences of behavioral score and the serum level of estradiol between QJFB group and control group.</p><p><b>CONCLUSION</b>The chronic unpredictable stress can induce the stressful change of behavior, and QJFB may recover the rats'abnormal behavior and improve the serum level of estradiol. QJFB may have protective effect on stress.</p>

Identification of a lens-specific cis-acting element within the basal promoter of the human lens intrinsic membrane protein MP19 gene (LIM2) / 生物工程学报

Using overlapping and mutant oligonucleotides as probes, gel mobility assays and competition experiments identified a sequence from -47 to -32 bp upstream of the LIM2 CAP site, which a lens protein complex bound with high affinity which appeared to bind only to the "sense" strand of the double-stranded DNA molecule. This sequence consisted of a string of four guanine residues followed by seven other nucleotides (AACCTAA) and followed by another four guanines, i.e. GGGGAACCTAAGGGG, called the Hsu element. Promoter-CAT constructs containing this sequence or mutations of the sequence indicated that the Hsu element is located within the basal promoter, and is essential for expression of the LIM2 gene. The trans factors binding to the Hsu element are present throughout development, and appear to be lens-specific. Since the LIM2 gene promoter does not contain a classic TATA box, the Hsu element may serve as the site for binding the RNA polymerase complex.