Serum concentrations of selected endogenous estrogen and estrogen metabolites in pre- and post-menopausal Chinese women with osteoarthritis

The purpose of this study was to investigate whether serum levels of selected endogenous estrogens and their metabolites are involved in the pathogenesis of osteoarthritis in pre- and post-menopausal women with osteoarthritis. Sixty-four patients with osteoarthritis (OA) of the knee, 48 patients with rheumatoid arthritis (RA) of the knee, and 48 healthy women were included in this study. Serum concentrations of estradiol and estrogen metabolites, such as 2- hydroxyestrone, 2-hydroxyestradiol, and 16α-hydroxyestrone, were measured by high performance liquid chromatography-mass spectrometry. Our results show that the serum concentrations of free estradiol and total 2-hydroxyestrone were significantly lower in pre-menopausal women with OA compared to the levels detected in the control groups (RA and healthy women). While serum concentrations of free and total estradiol in post-menopausal women with OA was significantly decreased compared to those of the control groups, the level of total 2-hydroxyestradiol significantly increased in postmenopausal women. Furthermore, the total 2-hydroxyestrone concentration positively correlated with the total estradiol level in pre-menopausal women with OA. In addition, the total 2- hydroxyestradiol level positively correlated with free and total estradiol levels in post-menopausal women with OA. In conclusion, estradiol and estrogen metabolites, including 2-hydroxyestrone and 2-hydroxyestradiol, were found in the sera of pre- and post-menopausal women with OA. Except for free and total estradiol deficiency, a decreased serum level of total 2- hydroxyestrone in pre-menopausal women and an increased total 2-hydroxyestradiol level in post-menopausal women with OA may also correlate with the pathogenesis of female OA.

Disclosure of HIV-positive serostatus to sexual partners and associated factors in southern China

In light of an increased push for disclosure of HIV-positive serostatus to sexual partners (partner disclosure, PD) in China as reflected by national and local policies, the objective of this study was to determine the proportion and evaluate associated factors of PD among people living with HIV/AIDS (PLWHA) in HIV/AIDS high-risk areas in southern China. Of the 946 HIV-positive individuals, the proportion of those who disclosed positive serostatus results to their sexual partners was 90.2% (625/693). Variables independently associated with non-disclosure included testing in Guangxi province (adjusted relative ratio [ARR] = 0.33), becoming infected with HIV via injecting drug use (IDU) transmission (ARR = 0.32), having not reported discussing disclosure with health department staff during post-test counselling (ARR = 0.41) and having a sexual relationship of ≤2 years' duration (ARR = 0.31). This study also identified a relatively larger differential between the proportion of disclosure to regular partners and the proportion of disclosure to casual partners (94.8% versus 13.0%) in comparison with other studies. Findings from this study may aid policies for future consideration.

The influence of complete coronary revascularization on long-term outcomes in patients with multivessel coronary heart disease undergoing successful percutaneous coronary intervention

The influence of complete revascularization (CR) compared with incomplete revascularization (ICR) on long-term outcomes was assessed in patients with multivessel coronary heart disease undergoing successful percutaneous coronary intervention (PCI). A retrospective analysis of the clinical data, lesion type and PCI data was carried out in 324 patients with multivessel coronary heart disease (CR group, 99 patients; ICR group, 225 patients). Major adverse cardiac events (MACE) were recorded at follow-up (mean +/- SD follow-up interval, 18 +/- 7.1 months). There were no significant differences in clinical characteristics between the two groups at follow-up, although the CR group showed a non-significant tendency to a higher incidence of non-fatal myocardial infarction, cardiac death, repeated revascularization and MACE compared with the ICR group. In conclusion, the long-term prognosis for ICR was not inferior to that for CR in patients with multivessel coronary heart disease undergoing successful PCI.

Decreased chaperone activity of alpha-crystallins in naphthalene-induced cataract possibly results from C-terminal truncation

Naphthalene-induced cataract has been extensively used to test potential anticataract drugs. Because the morphology as well as the toxic manifestations of naphthalene-induced cataract are reported to be similar to that of age-related cataract, naphthalene cataractogenesis in rats has been used as a valuable animal model to study the aetiology of age-related cataract in humans. This study aimed to determine whether the molecular chaperone activity of the alpha-crystallins was altered in naphthalene-induced cataract, and to clarify the possible mechanism for these changes. The data showed that the chaperone activity of the alpha-crystallins decreased in naphthalene-induced cataract. By mass spectrometry, C-terminal truncation of 16 amino acids and other post-translational modifications such as acetylation, phosphorylation, oxidation and carbamylation of the alpha-crystallins were detected. Furthermore, the results suggested that, at the proteomics level, naphthalene-induced cataract is a valuable animal model for the study of age-related cataract in humans.

Thermoelectric properties of graphene nanoribbons, junctions and superlattices

Using model interaction Hamiltonians for both electrons and phonons and Green's function formalism for ballistic transport, we have studied the thermal conductance and the thermoelectric properties of graphene nanoribbons (GNR), GNR junctions and periodic superlattices. Among our findings we have established the role that interfaces play in determining the thermoelectric response of GNR systems both across single junctions and in periodic superlattices. In general, increasing the number of interfaces in a single GNR system increases the peak ZT values that are thus maximized in a periodic superlattice. Moreover, we proved that the thermoelectric behavior is largely controlled by the width of the narrower component of the junction. Finally, we have demonstrated that chevron-type GNRs recently synthesized should display superior thermoelectric properties.

Thymidine kinase 1 is a potential marker for prognosis and monitoring the response to treatment of patients with breast, lung, and esophageal cancer and non-Hodgkin's lymphoma

Thymidine kinase 1 (TK1) is converting thymidine to thymidine monophosphate, and is related to DNA replication and cell proliferation. The use of the TK1 protein levels as a proliferation marker in malignancies is here summarized. TK1 protein in serum (STK1p) and TK1 expression in tissues were determined by a chemoluminescent dot blot assay and by immunohistochemistry staining, respectively. The expression of TK1 in tumor tissues correlated to pathological stages and clinical grades of carcinomas (ca) of esophagus, lung and in premalignancy of breast ductal ca. STK1p could monitor the out-come of tumor therapy by being correlated to remission [breast ca, non-Hodgkin's lymphoma], relapse [breast ca] and to survival [non-Hodgkin's lymphoma] of patients. In a health screening study of 12,641 persons, STK1p seemed to predict the risk of development of neoplasia related diseases at early stage.

Delayed treatment effects of xanthine oxidase inhibition on systolic overload-induced left ventricular hypertrophy and dysfunction

The nonpurine selective xanthine oxidase (XO) inhibitor febuxostat attenuates development of left ventricular (LV) hypertrophy and dysfunction in mice when treatment is initiated within 1 hour of transverse aortic constriction (TAC). This study investigated whether a 7-day delay of treatment with the XO inhibitors febuxostat or allopurinol would reverse TAC-induced changes after onset of heart failure (HF). Neither treatment significantly affected TAC-induced LV hypertrophy; only febuxostat caused a modest improvement in LV function (∼10% increase in LV ejection fraction). However, the purine analog allopurinol tended to increase mortality compared with vehicle or febuxostat in HF mice.

Treatment with peginterferon versus interferon in Chinese patients with chronic hepatitis C

Higher sustained virological response (SVR) rates after treating with peginterferon than after treating with interferon have been obtained in some randomized clinical trials (RCTs) in Chinese patients with chronic hepatitis C (CHC). However, the numbers of patients included in these clinical trials were too small to draw a clear conclusion. Therefore, a new meta-analysis including a large number of patients was needed to compare peginterferon with interferon in the treatment of Chinese CHC patients. A search of Medline, the China National Knowledge Infrastructure, the Wanfang Database, and the China Biomedical Database for relevant articles published between 1966 and 2009 was performed. RCTs comparing the use of peginterferon and interferon for the treatment of Chinese patients with CHC were assessed. Of the 236 studies screened, 18 RCTs including 1,148 patients (659 treated with peginterferon therapy and 489 treated with interferon therapy) were analyzed. The total SVR rates obtained in patients treated with peginterferon were significantly higher than those obtained in patients treated with interferon (64% vs. 40%; relative risk, 1.56; 95% confidence interval: 1.28-1.91; p < 0.01), but the difference between the peginterferon α-2b and interferon α-2b treatments was not significant. Withdrawal rates were similar between patients treated with peginterferon and interferon. Chinese patients with CHC have a greater likelihood of achieving an SVR with peginterferon α-2a.

Polymorphisms of PXK are associated with autoantibody production, but not disease risk, of systemic lupus erythematosus in Chinese mainland population

Systemic lupus erythematosus (SLE) is a complex immune disease. The genetic variation in the PXK gene was found to associate with SLE in Caucasian populations. However, the association of rs6445975 with SLE has not been extensively studied in a Chinese mainland population. A total of 288 SLE patients and 357 controls were recruited. Unlabeled probe-based high-resolution melting analysis (HRMA) was used in genotyping. HRMA with unlabeled probe successfully distinguished all genotypes. Neither genotype nor allele frequencies of SNP rs6445975 showed statistically significant differences between SLE patients and controls. The association of SNP rs6445975 with the diagnostic criteria of SLE was also examined. No obvious association was observed between rs6445975 and the incidence of clinical symptoms. However, the minor allele (G) of rs6445975 was found to significantly associate with increased abnormalities of anti-Smith (p = 0.004, odds ratio (OR) = 1.95, 95% confidence interval (CI) = 1.22-3.09), anti-Ro (p = 0.015, OR = 1.69, 95% CI = 1.10-2.58), anti-La (p = 0.008, OR = 1.86, 95% CI = 1.17-2.93) and C3C4 (p = 0.007, OR = 1.79, 95% CI = 1.17-2.74). Polymorphisms of rs6445975 in the PXK gene were associated with autoantibody production, but not disease risk, of systemic lupus erythematosus in a Chinese population.

Overexpression of C-MYC oncogene in prostate cancer predicts biochemical recurrence

Alterations of chromosome 8, including amplification at 8q24 harboring the C-MYC oncogene, have been noted as one of the most common chromosomal abnormalities in prostate cancer (CaP) progression. However, the frequency of C-MYC alterations in CaP has remained uncertain. A recent study, using a new anti-MYC antibody, described prevalent upregulation of nuclear C-MYC protein expression as an early oncogenic alteration in CaP. Further, we have recently reported regulation of C-MYC expression by ERG and a significant correlation between C-MYC overexpression and TMPRSS2-ERG fusion in early stage CaP. These emerging data suggest that increased C-MYC expression may be a critical and early oncogenic event driving CaP progression. In this study, we assessed whether C-MYC mRNA overexpression in primary prostate tumors was predictive of more aggressive tumor or disease progression. Our approach was to quantitatively determine C-MYC mRNA expression levels in laser capture micro-dissected tumor cells and matched benign epithelial cells in a radical prostatectomy cohort with long follow-up data available. On the basis of our results, we conclude that elevated C-MYC expression in primary prostate tumor is biologically relevant and may be a predictor of future biochemical recurrence.

An investigation of cancer incidence in a First Nations community in Alberta, Canada, 1995–2006

Objective

To determine colorectal and overall cancer incidence as part of a three-pronged investigation in response to the concerns of a First Nations community in Alberta, Canada, located close to sulfur-rich natural gas installations, and to determine whether the incidence of cancers observed in this reserve was higher than expected.

Methods

A population dataset with information identifying First Nations status and band affiliation was linked to the Alberta Cancer Registry to determine cancer incidence cases between 1995 and 2006 for on- and off-reserve study populations. Using indirect standardized incidence ratios, observed cancer incidence cases for the study populations were compared with cases expected based on three separate reference populations.

Results

Observed colorectal and overall cancer incidence cases within the First Nations community were not higher than expected. Cervical cancer incidence cases, however, were higher than expected for on- and off-reserve populations; public health measures designed to address this risk have been implemented and on-going surveillance of cancer incidence in the community will be maintained.

An investigation of cancer incidence in a First Nations community in Alberta, Canada, 1995-2006

OBJECTIVE

To determine colorectal and overall cancer incidence as part of a three-pronged investigation in response to the concerns of a First Nations community in Alberta, Canada, located close to sulfur-rich natural gas installations, and to determine whether the incidence of cancers observed in this reserve was higher than expected.

METHODS

A population dataset with information identifying First Nations status and band affiliation was linked to the Alberta Cancer Registry to determine cancer incidence cases between 1995 and 2006 for on- and off-reserve study populations. Using indirect standardized incidence ratios, observed cancer incidence cases for the study populations were compared with cases expected based on three separate reference populations.

RESULTS

Observed colorectal and overall cancer incidence cases within the First Nations community were not higher than expected. Cervical cancer incidence cases, however, were higher than expected for on- and off-reserve populations; public health measures designed to address this risk have been implemented and on-going surveillance of cancer incidence in the community will be maintained.

Utility of the carboxylesterase inhibitor bis-para-nitrophenylphosphate (BNPP) in the plasma unbound fraction determination for a hydrolytically unstable amide derivative and agonist of the TGR5 receptor

The potent, functional agonist of the bile acid Takeda G-protein-coupled receptor 5 (TGR5), (S)-1-(6-fluoro-2-methyl-3,4-dihydroquinolin-1(2H)-yl)-2-(isoquinolin-5-yloxy)ethanone (3), represents a useful tool to probe in vivo TGR5 pharmacology. Rapid degradation of 3 in both rat and mouse plasma, however, hindered the conduct of in vivo pharmacokinetic/pharmacodynamic investigations (including plasma-free fraction (f(u plasma)) determination) in rodent models of pharmacology. Studies were therefore initiated to understand the biochemical basis for plasma instability so that appropriate methodology could be implemented in in vivo pharmacology studies to prevent the breakdown of 3. Compound 3 underwent amide bond cleavage in both rat and mouse plasma with half-lives (T(1/2)) of 39 + or - 7 and 9.9 + or - 0.1 min. bis(p-nitrophenyl) phosphate (BNPP), a specific inhibitor of carboxylesterases, was found to inhibit hydrolytic cleavage in a time- and concentration-dependent manner, which suggested the involvement of carboxylesterases in the metabolism of 3. In contrast with the findings in rodents, 3 was resistant to hydrolytic cleavage in both dog and human plasma. The instability of 3 was also observed in rat and mouse liver microsomes. beta-Nicotinamide adenine dinucleotide phosphate, reduced form (NADPH)-dependent metabolism of 3 occurred more rapidly (T(1/2) approximately 2.22-6.4 min) compared with the metabolic component observed in the absence of the co-factor (T(1/2) approximately 89-130 min). Oxidative metabolism dominated the NADPH-dependent decline of 3, whereas NADPH-independent metabolism of 3 proceeded via simple amide bond hydrolysis. Compound 3 was highly bound (approximately 95%) to both dog and human plasmas. Rat and mouse plasma, pre-treated with BNPP to inhibit carboxylesterases activity, were used to determine the f(u plasma) of 3. A BNPP concentration of 500 microM was determined to be optimal for these studies. Higher BNPP concentrations (1000 microM) appeared to displace 3 from its plasma protein-binding sites in preclinical species and human. Under the conditions of carboxylesterases-inhibited rat and mouse plasma, the level of protein binding displayed by 3 was similar to those observed in dog and human. In conclusion, a novel system has been devised to measure f(u plasma) for a plasma-labile compound. The BNPP methodology can be potentially applied to stabilize hydrolytic cleavage of structurally diverse carboxylesterase substrates in the plasma (and other tissue), thereby allowing the characterization of pharmacology studies on plasma-labile compounds if and when they emerge as hits in exploratory drug-discovery programmes.

Effect of glycyrrhizin on CYP2C19 and CYP3A4 activity in healthy volunteers with different CYP2C19 genotypes

The objective of this study was to investigate the interaction between glycyrrhizin and omeprazole and observe the effects of glycyrrhizin on CYP2C19 and CYP3A4 activities in healthy Chinese male volunteers with different CYP2C19 genotypes. Eighteen healthy subjects (six CYP2C19*1/*1, five CYP2C19*1/*2, one CYP2C19*1/*3, five CYP2C19*2/*2 and one CYP2C19*2/*3) were enrolled in a two-phase randomized crossover trial. In each phase, all subjects received placebo or glycyrrhizin salt tablet 150 mg twice daily for 14 consecutive days. The pharmacokinetics of omeprazole (20 mg orally on day 15) was determined for up to 12 h following administration by high-performance liquid chromatography. After 14-day treatment of glycyrrhizin, plasma omeprazole significantly decreased, and those of omeprazole sulfone significantly increased. However, plasma concenetrations of 5-hydroxyomeprazole did not significantly change. The ratio of AUC(0-infinity) of omeprazole to omeprazole sulfone decreased by 43.93% + or - 13.56% (p = 0.009) in CYP2C19*1/*1, 44.85% + or - 14.84% (p = 0.002) in CYP2C19*1/*2 or *3 and 36.16% + or - 7.52% (p < 0.001) in CYP2C19*2/*2 or *3 while those of omeprazole to 5-hydroxyomeprazole did not change significantly in all three genotypes. No significant differences in glycyrrhizin response were found among CYP2C19 genotypes. Glycyrrhizin induces CYP3A4-catalyzed sulfoxidation of omeprazole and leads to decreased omeprazole plasma concentrations, but has no significant impact on CYP2C19-dependent hydroxylation of omeprazole.

Alterations in the proteome of the NHERF1 knockout mouse jejunal brush border membrane vesicles

Na/H exchanger regulatory factor 1 (NHERF1) is a scaffold protein made up of two PDZ domains and an ERM binding domain. It is in the brush border of multiple epithelial cells where it modulates 1) Na absorption by regulating NHE3 complexes and cytoskeletal association, 2) Cl secretion through trafficking of CFTR, and 3) Na-coupled phosphate absorption through membrane retention of NaPi2a. To further understand the role of NHERF1 in regulation of small intestinal Na absorptive cell function, with emphasis on apical membrane transport regulation, quantitative proteomic analysis was performed on brush border membrane vesicles (BBMV) prepared from wild-type (WT) and homozygous NHERF1 knockout mouse jejunal villus Na absorptive cells. Jejunal architecture appeared normal in NHERF1 null; however, there was increased proliferative activity, as indicated by increased crypt BrdU staining. LC-MS/MS analysis using iTRAQ to compare WT and NHERF1 null BBMV identified 463 proteins present in both WT and NHERF1 null BBMV of simultaneously prepared and studied samples. Seventeen proteins had an altered amount of expression between WT and NHERF1 null in two or more separate preparations, and 149 total proteins were altered in at least one BBMV preparation. The classes of the majority of proteins altered included transport proteins, signaling and trafficking proteins, and proteins involved in proliferation and cell division. Affected proteins also included tight junction and adherens junction proteins, cytoskeletal proteins, as well as metabolic and BB digestive enzymes. Changes in abundance of several proteins were confirmed by immunoblotting [increased CEACAM1, decreased ezrin (p-ezrin), NHERF3, PLCβ3, E-cadherin, p120, β-catenin]. The changes in the jejunal BBMV proteome of NHERF1 null mice are consistent with a more complex role of NHERF1 than just forming signaling complexes and anchoring proteins to the apical membrane and include at least alterations in proteins involved in transport, signaling, and proliferation.

Laboratory and field assessments of prey-mediated effects of transgenic Bt rice on Ummeliata insecticeps (Araneida: Linyphiidae)

One major concern regarding the release of Bt rice is its potential impact through tritrophic interactions on nontarget arthropods, especially natural enemies. We studied the effects of two Bt transgenic rice varieties, TT9- 3 and KMD1, expressing Cry1Ab/Cry1Ac and Cry1Ab, respectively, on a predatory ground spider [Ummeliata insecticeps (Bösenberg et Strand)] supplied with Bt rice-fed brown planthopper [Nilaparvata lugens (Stål)] nymphs. Although immunoassays confirmed that U. insecticeps ingested Bt insecticidal protein when supplied with Bt rice-fed N. lugens, no negative effects were found on its survival and development. Furthermore, the fecundity of U. insecticeps fed prey reared on Bt rice was not significantly different from that of those fed prey reared on non-Bt rice. A 3-yr field trial indicated that Bt rice did not significantly affect the population density of U. insecticeps in comparison with non-Bt rice. In conclusion, the Bt rice lines tested in this study had no adverse effects on the survival, developmental time, or fecundity of U. insecticeps in the laboratory or on population dynamics in the field.

Highly emissive multiexcitons in steady-state photoluminescence of individual "giant" CdSe/CdS Core/Shell nanocrystals

The development of nanocrystal quantum dots (NQDs) with suppressed nonradiative Auger recombination has been an important goal in colloidal nanostructure research motivated by the needs of prospective applications in lasing devices, light-emitting diodes, and photovoltaic cells. Here, we conduct single-nanocrystal spectroscopic studies of recently developed core-shell NQDs (so-called "giant" NQDs) that comprise a small CdSe core surrounded by a 16-monolayer-thick CdS shell. Using both continuous-wave and pulsed excitation, we observe strong emission features due both to neutral and charged biexcitons, as well as multiexcitons of higher order. The development of pronounced multiexcitonic peaks in steady-state photoluminescence of individual nanocrystals, as well as continuous growth of the emission intensity in the range of high pump levels, point toward a significant suppression of nonradiative Auger decay that normally renders multiexcitons nonemissive. The unusually high multiexciton emission efficiencies in these systems open interesting opportunities for studies of multiexciton phenomena using well-established methods of single-dot spectroscopy, as well as new exciting prospects for applications, that have previously been hampered by nonradiative Auger decay.

Modification of electronic properties of graphene with self-assembled monolayers

Integration of organic and inorganic electronic materials is one of the emerging approaches to achieve novel material functionalities. Here, we demonstrate a stable self-assembled monolayer of an alkylsilane grown at the surface of graphite and graphene. Detailed characterization of the system using scanning probe microscopy, X-ray photoelectron spectroscopy, and transport measurements reveals the monolayer structure and its effect on the electronic properties of graphene. The monolayer induces a strong surface doping with a high density of mobile holes (n > 10(13) cm(-2)). The ability to tune electronic properties of graphene via stable molecular self-assembly, including selective doping of steps, edges, and other defects, may have important implications in future graphene electronics.

Nuclear translocation of telomerase reverse transcriptase: a critical process in chemical induced hepatocellular carcinogenesis

Telomerase, a ribonuclearprotein complex, functions not only in cancer development but also in apoptosis, and senescence. As a catalytic subunit of telomerase, telomerase reverse transcriptase (TERT) has been confirmed to regulate telomerase activity in a rate-limiting manner. Although a lot of work has been done, the dynamic state of TERT protein and the relationship with telomerase have not been delineated systematically in cancer development. The purpose of this study was to do such an exploration. To investigate the role of TERT in the in vivo carcinogenesis, we performed immunofluorescence and Western blot analysis, respectively, to detect the alteration of TERT status as well as telomeric repeat amplification protocol (TRAP) assay to detect telomerase activity in diethyl nitrosoamine (DENA) induced rat hepatocellular carcinoma (HCC). The course of cancer development was divided into three main stages, which were inflammation ( <12 weeks), hepatocirrhosis (15 weeks), and hepatocarcinoma (18-21 weeks). In normal liver and its early inflammatory stage, concomitant with a weak positive TERT signal, which was detected exclusively in the cytoplasm, telomerase activity was very low at this stage. However, in late hepatocirrhosis and particularly cancer stage, high levels of TERT expression (P = 0.044 and P = 0.001, respectively) and telomerase activity (P = 0.02 and P = 0.01, respectively) were observed following TERT nuclear translocation. Our data suggest that TERT protein might regulate telomerase activity. TERT translocation from cytoplasm to the nucleus might be a turning point in cancer development. Therefore, TERT translocation might be more useful than TERT expression level and telomerase activity in predicting the progression of HCC.