Identification of inhibitors against p90 ribosomal S6 kinase 2 (RSK2) through structure-based virtual screening with the inhibitor-constrained refined homology model

P90 ribosomal S6 kinase 2 (RSK2), which was shown to be overexpressed in human cancers, is a serine/threonine kinase and a potential target for cancer treatment. RSK2 comprises two terminal kinase domains (NTKD and CTKD) that can be inhibited by binding with different types of inhibitors at the ATP binding sites. In the absence of a crystal structure of RSK2, we constructed a model for the 3D structure of the RSK2 NTKD by homology modeling and stepwise constrained refinement with the reported inhibitors using a molecular docking method. Structure-based virtual screening was subsequently performed against a library containing commercially available compounds using the refined model. This resulted in the identification of seven novel RSK2 inhibitors with IC₅₀ values ranging from 2.4 to 14.45 μM.

Preclinical pharmacology of TP1, a novel potent triple reuptake inhibitor with antidepressant properties

Triple reuptake inhibitors (TRIs) that block the dopamine transporter (DAT), norepinephrine transporter (NET), and serotonin transporter (SERT) are being developed as a new class of antidepressant that may have better efficacy and fewer side effects compared with traditional antidepressants. The purpose of this study was to characterize a new chemical entity, 4-[2-(dimethylamino)-1-(1-hydroxycyclohexyl)ethyl] phenyl 4-methoxybenzoate hydrochloride (TP1). TP1 was designed as a prodrug of desvenlafaxine. Competitive radioligand binding assays were performed using cells expressing the human dopamine (DA) transporter (hDAT), the human serotonin (5-HT) transporter (hSERT), and the human norepinephrine (NE) transporter (hNET) with K(i) values for TP1 of 190 nM, 2076 nM, and 1023 nM, respectively. Uptake assays were performed with IC(50) values for TP1 of 712 nM, 521 nM, and 628 nM, respectively. TP1 (0.06 mmol/kg, orally) rapidly penetrated rat brain and hypothalamus, translated into desvenlafaxine within 1 h, and demonstrated higher bioavailability and better pharmacokinetic properties than desvenlafaxine succinate (DVS). TP1 (0.06 mmol/kg, orally) significantly increased extracellular levels of DA, NE, and 5-HT compared with baseline in the rat hypothalamus by microdialysis assay. In dose-response assays, oral administration of TP1 reduced the time of immobility in a dose-dependent manner during tail suspension test and forced swimming test (FST). This antidepressant-like effect manifests in the absence of significant increases in motor activity even at doses of up to 32 mg/kg. The ability of TP1 to inhibit the reuptake of three biogenic amines closely linked to the etiology of depression may result in a therapeutic profile different from antidepressants that inhibit the reuptake of serotonin and/or NE.

First-trimester placental protein 13, PAPP-A, uterine artery Doppler and maternal characteristics in the prediction of pre-eclampsia

OBJECTIVE

To test the hypothesis that a combination of PP13, PAPP-A and first-trimester uterine artery Doppler would improve the prediction of pre-eclampsia.

METHODS

This is a prospective cohort study of pregnant women followed from the first-trimester to delivery. PP13 and PAPP-A were determined by immunoassay of maternal serum at 11-14 weeks', when uterine artery Doppler measurements were assessed. Cases identified with any form of pre-eclampsia were compared with a control group without pre-eclampsia. The sensitivity of each marker or their combinations in predicting pre-eclampsia for different fixed false positive rates was calculated from the ROC curves.

RESULTS

Forty two women were diagnosed with pre-eclampsia and 410 women with pregnancies not complicated by pre-eclampsia were used as controls. For a fixed false positive rate (FPR) of 20%, PP13, PAPP-A and mean uterine artery pulsatility index identified 49%, 58% and 62% respectively, of women who developed any form of pre-eclampsia. PP13 was best in predicting early onset pre-eclampsia with a sensitivity of 79% at a 20% FPR. Combinations of the three first-trimester assessments did not improve the prediction of pre-eclampsia in later pregnancy.

CONCLUSION

First-trimester PP13, PAPP-A and uterine artery PI are reasonable, individual predictors of women at risk to develop pre-eclampsia. Combinations of these assessments do not further improve the prediction of pre-eclampsia.

Genotypic resistance profile of hepatitis B virus (HBV) in a large cohort of nucleos(t)ide analogue-experienced Chinese patients with chronic HBV infection

The study investigated the hepatitis B virus (HBV) genotypic resistance profile in 1803 nucleos(t)ide analogue (NA)-experienced Chinese patients with chronic HBV infection. Serum HBV DNA was extracted, and the reverse transcriptase region was analysed by a high-sensitive direct PCR sequencing and verified by clonal sequencing if necessary. Drug-resistant mutations were detected in 560 of the 1803 patients, including 214 of 490 patients who received lamivudine (LAM), 35 of 428 patients who received adefovir (ADV), five of 18 patients who received telbivudine and 306 of 794 patients who received various sequential/combined NA therapies. ADV-resistant mutations were detected in 36 of 381 patients who received LAM and then switched-to ADV in contrast to one of 82 patients who received ADV add-on LAM. Entecavir (ETV)-resistant mutations were detected not only in LAM- and ETV-treated patients but also in LAM-treated ETV-naïve patients. Double mutations rtM204I and rtL180M were detected more frequently in genotype C than in genotype B virus, and patients infected with this mutant had higher alanine transaminase levels than those infected with mutant containing the rtM204I substitution alone. Multidrug-resistant HBV strains were identified in eight patients, including two novel strains with mutational patterns rtL180M + A181V + S202G + M204V + N236T and rtL180M + S202G + M204V + N236T. The results provide new information on HBV genotypic resistance profiles in a large cohort of Chinese patients with chronic HBV infection and may have important clinical implication for HBV drug resistance management in China.

Selective Rapid Thermal Cvd of Germanium

Selective depositions of germanium thin films have been investigated in a cold-wall, lamp heated rapid thermal processor. Films were deposited at low pressures (1 Torr-8 Torr) using the thermal decomposition of germane. Selectivity was maintained throughout the temperature range investigated, 350°C-600°C. Growth rates as high as 800 Å/min were obtained at 425°C where deposition is controlled by the surface reactions, making germanium compatible with the throughput requirements of single wafer manufacturing. Three dimensional growth was seen at temperatures above 450°C resulting in a rough surface morphology. Smooth films were deposited below 450°C with the films characterized by two dimensional growth. In this work, germanium is considered as a potential material to fabricate MOS transistors with raised source and drain junctions (UPMOS). Kelvin structures were fabricated to study the effect of the intermediate germanium layer between aluminum and silicon on contact resistance. It is shown that contact resistivity is improved by approximately 17% using an Al/p-Ge/p+-Si structure. In this work, it is also shown that titanium germanide formation can be used as a means of reducing the resistivity of the Ge buffer layer.

First-trimester serum analytes, biophysical tests and the association with pathological morphometry in the placenta of pregnancies with preeclampsia and fetal growth restriction

OBJECTIVE

We test the hypothesis that first-trimester serum analytes, 4-D power Doppler placental vascular indices and uterine artery Doppler (UAD) predicts abnormal placental morphometry in pregnancies with preeclampsia (PE) and fetal growth restriction (FGR).

STUDY DESIGN

Maternal serum analytes (PAPP-A, hCG, ADAM12s, and PP13), bilateral UADs, and placental vascular indices were measured at 11-14 weeks in a nested-case control study within a prospective cohort of women followed from the first-trimester to delivery. Vascularization index (VI), flow index (FI), and vascularization flow index (VFI) were obtained from 4-D power Doppler histograms. Serum analytes were measured using immunofluorometric assays and values converted to multiples of the median (MoM) for gestational age. Morphometric analysis was performed on placentas from pregnancies complicated by PE (n = 13), gestational hypertension (HBP, n = 7) and FGR (defined as fetal weight <10th percentile with abnormal umbilical artery Doppler: n = 7); and 20 uncomplicated pregnancies. Two pregnancies had both FGR and PE. Each placenta was weighed and random samples taken, and fixed in formalin within 1 h of delivery. Hematoxylin & Eosin stained slides were analyzed by design-based stereology to quantify linear dimensions, surface areas and volumes of placental components. Paired t-test and ANOVA with adjustments for multiple comparisons were used.

RESULTS

The surface areas of terminal and intermediate villi as well as the volume of terminal villi were significantly smaller in placentas from pregnancies complicated by FGR and PE. Compared with the control group the mean PAPP-A (MoM) was lower in the pregnancies with abnormal placenta morphometry (1.1 ± 0.5 versus 0.7 ± 0.5, P = 0.03). The morphometric indices were lower in those pregnancies with low PAPP-A and IUGR compared with preeclampsia.

CONCLUSION

First-trimester PAPP-A levels are associated with abnormal placental morphometry at delivery in pregnancies with PE and IUGR. These findings may explain the association between adverse pregnancy outcomes and first-trimester PAPP-A.

Effects of caesarean section on maternal health in low risk nulliparous women: a prospective matched cohort study in Shanghai, China

BACKGROUND

Rates of caesarean section are progressively increasing in many parts of the world. As a result of psychosocial factors there has been an increasing tendency for pregnant women without justifiable medical indications for caesarean section to ask for this procedure in China. A critical examination of this issue in relation to maternal outcomes is important. At present there are no clinical trials to help assess the risks and benefits of caesarean section in low risk women. To fill the gap left by trials, this indication-matched cohort study was carried out to examine prospectively the outcomes of caesarean section on women with no absolute obstetric indication compared with similar women who had vaginal delivery.

METHODS

An indication-matched cohort study was undertaken to compare maternal outcomes following caesarean section with those undergoing vaginal delivery, in which the two groups were matched for non-absolute indications. 301 nulliparous women with caesarean section were matched successfully with 301 women who delivered vaginally in the Maternal and Children's Hospitals (MCHs) in Shanghai, China. Logistic regression model or binomial regression model was used to estimate the relative risk (RR) directly. Adjusted RRs were calculated adjusting for propensity score and medical indications.

RESULTS

The incidence of total complications was 2.2 times higher in the caesarean section group during hospitalization post-partum, compared with the vaginal delivery group (RR = 2.2; 95% CI: 1.1-4.4). The risk of haemorrhage from the start of labour until 2 hours post-partum was significantly higher in the caesarean group (RR = 5.6; 95% CI: 1.2-26.9). The risk of chronic abdominal pain was significantly higher for the caesarean section group (RR = 3.6; 95% CI: 1.2-10.9) than for the vaginal delivery group within 12 months post-partum. The two groups had similar incidences of anaemia and complicating infections such as wound complications or urinary tract infection.

CONCLUSIONS

In nulliparous women who were at low risk, caesarean section was associated with a higher rate of post-partum morbidity. Those requesting the surgical procedure with no conventional medical indication, should be advised of the potential risks.

Hepatitis B virus genotype and basal core promoter/precore mutations are associated with hepatitis B-related acute-on-chronic liver failure without pre-existing liver cirrhosis

The study was undertaken to investigate the features and clinical implications of hepatitis B virus (HBV) genotypes, basal core promoter (BCP) and precore (PC) mutations in hepatitis B-related acute-on-chronic liver failure (HB-ACLF). Samples from 75 patients with HB-ACLF and without pre-existing liver cirrhosis and 328 age-matched patients with chronic hepatitis B (CHB) were analyzed. HBV genotype and BCP/PC mutations were determined by direct sequencing. Mutations at 8 sites of the BCP/PC region were compared between the two groups of patients. A significantly higher ratio of genotype B to C was found in patients with HB-ACLF than in patients with CHB (30.7-69.3% vs 16.5-82.6%, P < 0.01). Single mutations including T1753V (C/A/G), A1762T, G1764A, G1896A and G1899A and triple mutations T1753V/A1762T/G1764A and A1762T/G1764A/C1766T (or T1768A) were more frequently detected in patients with HB-ACLF than in patients with CHB. Correspondingly, BCP/PC wild-type sequences were absent in patients with HB-ACLF in contrast to 27.1% in patients with CHB. The BCP/PC mutations were found to be associated with increased HBeAg negativity, higher alanine aminotransferase level and lower viral load. Patients with HB-ACLF infected with the PC mutant virus had a higher mortality. The findings suggest that patients with CHB infected with genotype B with BCP/PC mutations were more likely to develop HB-ACLF than those with genotype C with wild-type BCP/PC regions, and patients with HB-ACLF with the PC mutation had increased risk of a fatal outcome.

Marginal and mixed-effects models in the analysis of human papillomavirus natural history data

Human papillomavirus (HPV) natural history has several characteristics that, at least from a statistical perspective, are not often encountered elsewhere in infectious disease and cancer research. There are, for example, multiple HPV types, and infection by each HPV type may be considered separate events. Although concurrent infections are common, the prevalence, incidence, and duration/persistence of each individual HPV can be separately measured. However, repeated measures involving the same subject tend to be correlated. The probability of detecting any given HPV type, for example, is greater among individuals who are currently positive for at least one other HPV type. Serial testing for HPV over time represents a second form of repeated measures. Statistical inferences that fail to take these correlations into account would be invalid. However, methods that do not use all the data would be inefficient. Marginal and mixed-effects models can address these issues but are not frequently used in HPV research. The current study provides an overview of these methods and then uses HPV data from a cohort of HIV-positive women to illustrate how they may be applied, and compare their results. The findings show the greater efficiency of these models compared with standard logistic regression and Cox models. Because mixed-effects models estimate subject-specific associations, they sometimes gave much higher effect estimates than marginal models, which estimate population-averaged associations. Overall, the results show that marginal and mixed-effects models are efficient for studying HPV natural history, but also highlight the importance of understanding how these models differ.

Influence of adherent and effective antiretroviral therapy use on human papillomavirus infection and squamous intraepithelial lesions in human immunodeficiency virus-positive women

BACKGROUND

The impact of highly active antiretroviral therapy (HAART) on the natural history of human papillomavirus (HPV) remains uncertain following conflicting reports. Prior studies, however, did not consider patients' adherence to their regimens or HAART effectiveness (viral suppression).

METHODS

Human immunodeficiency virus (HIV)-positive women (N = 286) who initiated HAART during follow-up in a prospective cohort were assessed semiannually for HPV infection (by polymerase chain reaction) and squamous intraepithelial lesions (SILs). Adherence was defined as use of HAART as prescribed > or = 95% of the time, and effective HAART was defined as suppression of HIV replication. The prevalence, incident detection, and clearance of HPV infection and/or SILs before versus after HAART initiation were compared (using women as their own comparison group).

RESULTS

HAART initiation among adherent women was associated with a significant reduction in prevalence (odds ratio, 0.60 [95% confidence interval {CI}, 0.44-0.81]; P = .001), incident detection of oncogenic HPV infection (hazard ratio [HR], 0.49 [95% CI, 0.30-0.82]; P = .006), and decreased prevalence and more rapid clearance of oncogenic HPV-positive SILs (HR, 2.35 [95% CI, 1.07-5.18]; P = .03). Effects were smaller among nonadherent women. The associations of HPV infection and/or SILs with HAART effectiveness were fairly similar to those with HAART adherence.

CONCLUSION

Effective and adherent HAART use is associated with a significantly reduced burden of HPV infection and SILs; this may help explain why rates of cervical cancer have not increased during the HAART era, despite greater longevity.

Marijuana use is not associated with cervical human papillomavirus natural history or cervical neoplasia in HIV-seropositive or HIV-seronegative women

Marijuana use was recently reported to have a positive cross-sectional association with human papillomavirus (HPV)-related head and neck cancer. Laboratory data suggest that marijuana could have an immunomodulatory effect. Little is known, however, regarding the effects of marijuana use on cervical HPV or neoplasia. Therefore, we studied the natural history (i.e., prevalence, incident detection, clearance/persistence) of cervical HPV and cervical neoplasia (i.e., squamous intraepithelial lesions; SIL) in a large prospective cohort of 2,584 HIV-seropositive and 915 HIV-seronegative women. Marijuana use was classified as ever/never, current/not current, and by frequency and duration of use. No positive associations were observed between use of marijuana, and either cervical HPV infection or SIL. The findings were similar among HIV-seropositive and HIV-seronegative women, and in tobacco smokers and nonsmokers. These data suggest that marijuana use does not increase the burden of cervical HPV infection or SIL.

Outcomes for Patients With ST-Elevation Myocardial Infarction in Hospitals With and Without Onsite Coronary Artery Bypass Graft Surgery

Background— The benefit of primary percutaneous coronary interventions (P-PCI) for patients with ST-elevation myocardial infarction (STEMI) has been well documented. However, controversy still exists as to whether PCI should be expanded to hospitals without coronary artery bypass graft surgery.

Methods and Results— Patients who were discharged after PCI for STEMI between January 1, 2003, and December 12, 2006, in P-PCI centers (hospitals with no coronary artery bypass graft surgery, and PCI only for patients with STEMI) were propensity matched with patients in full service centers, and mortality and subsequent revascularization rates were compared. For patients undergoing PCI, there were no differences for in-hospital/30-day mortality (2.3% for P-PCI centers versus 1.9% for full service centers [ P =0.40]), emergency coronary artery bypass graft surgery immediately after PCI (0.06% versus 0.35%, P =0.06), 3-year mortality (7.1% versus 5.9%, P =0.07), or 3-year subsequent revascularization (23.8% versus 21.5%, P =0.52). P-PCI centers had a lower same/next day coronary artery bypass graft rate (0.23% versus 0.69%, P =0.046) and higher repeat target vessel PCI rates (12.1% versus 9.0%, P =0.003). For patients with STEMI who did not undergo PCI, P-PCI centers had higher in-hospital mortality (28.5% versus 22.3%; adjusted odds ratio, 1.38; 95% CI, 1.10 to 1.75).

Conclusions— No differences between P-PCI centers and full service centers were found in in-hospital/30-day mortality, the need for emergency surgery, 3-year mortality or subsequent revascularization, but P-PCI centers had higher repeat target vessel PCI rates and higher mortality rates for patients who did not undergo PCI. P-PCI centers should be monitored closely, including the monitoring of patients with STEMI who did not undergo PCI.

The anti-glioma effect of suicide gene therapy using BMSC expressing HSV/TK combined with overexpression of Cx43 in glioma cells

The disseminated neoplastic foci of malignant gliomas are essentially responsible for the limited efficacy of current available therapeutic modalities. Bone marrow-derived stem cells (BMSCs) have the ability to migrate into these tumors and even track infiltrating tumor cells, making them to be promising cellular vehicles for delivering therapeutic agents to glioma cells. The herpes simplex virus thymidine kinase (HSV-TK)/ganciclovir (GCV) suicide gene therapy with a potent bystander effect has been considered as one of the most promising therapeutic strategies for malignant gliomas. In this study, we evaluate the anti-glioma effect of suicide gene therapy using BMSCs expressing HSV-TK combined with overexpression of connexin 43 (Cx43), which can restore the gap junction of intercellular communication and may enhance the bystander effect of suicide gene therapy. To assess the potential of BMSCs to track glioma cells, a spheroid co-culture system in matrigel was used to show that some BMSCs migrated to C6 glioma cell microspheres. Transwell assay showed the tumor tropic property of BMSCs. In addition, BrdU-labeled BMSCs injected directly into the cerebral hemisphere opposite to the established C6 rat gliomas were capable of migrating into the xenograft gliomas. C6 cell growth was more intensively inhibited by HSV-TK/GCV treatment mediated by BMSCs, and could be further enhanced by combination with Cx43 transfection into glioma cells. The same result was observed in vivo by the growth of C6 gliomas and the survival analysis of rats bearing C6 glioma. In conclusion, Cx43 combined with HSV-TK/GCV gene therapy using BMSCs as vehicles was highly effective in a rat glioma model and therefore hold great potential as a novel approach for the gene therapy of human malignant gliomas.

Preoperative hepatic and regional arterial chemotherapy in the prevention of liver metastasis after colorectal cancer surgery

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Background: To investigate whether preoperative hepatic and regional arterial chemotherapy are able to prevent liver metastasis and improve overall survival in patients receiving curative colorectal cancer resection. Methods: Patients with Stage II or Stage III colorectal cancer (CRC) were randomly assigned to receive preoperative hepatic and regional arterial chemotherapy (PHRAC group, n=256) or surgery alone (control group, n=253). The primary endpoint was disease-free survival, whereas the secondary endpoints included liver metastasis-free survival and overall survival. Results: There were no significant differences in overall morbidity between PHRAC and Control groups. During the follow-up period (median, 42 months), the median liver metastasis time for patients with stage III CRC was significantly longer in the PHRAC group (16±3 months v.s. 8±1 months, P=0.01). In stage III patients, there was also significant difference between the two groups with regard to the incidence of liver metastasis (18.9% vs 27.3%, P=0.01), 5-year disease-free survival (70.2% vs 52.0%, P=0.0076), 5-year overall survival (80.3% vs 69.5%, P=0.020) and the median survival time (40.1± 4.6 months vs 36.3 ± 3.2 months, P=0.03). In the PHRAC arm, the risk ratio of recurrence was 0.63 (95% CI, 0.51–0.79, P=0.0001), of death was 0.50(95% CI, 0.32–0.67; P=0.005), and of liver metastasis was 0.70 (95% CI, 0.52–0.86; p=0.01). In contrast, PHRAC seemed to be no benefit for stage II patients. Toxicities, such as hepatic toxicity and leucocyte decreasing, were mild and could be cured with medicine. Conclusions: Preoperative hepatic and regional arterial chemotherapy, in combination with surgical resection, could be able to reduce and delay the occurrence of liver metastasis and therefore improve survival rate in patients with stage III colorectal cancer.

No significant financial relationships to disclose.