The phosphatidylinositol 3-kinase
(PI3K) signaling pathway plays
important roles in cell proliferation, growth, and survival. Hyperactivated
PI3K is frequently found in a wide variety of human cancers, validating
it as a promising target for cancer therapy. We determined the crystal
structure of the human PI3Kα–PI103 complex to unravel
molecular interactions. Based on the structure, substitution at the
R1 position of the phenol portion of PI103 was demonstrated
to improve binding affinity via forming a new H-bond with Lys802 at
the bottom of the ATP catalytic site. Interestingly, the crystal structure
of the PI3Kα–9d complex revealed that the
flexibility of Lys802 can also induce additional space at the catalytic
site for further modification. Thus, these crystal structures provide
a molecular basis for the strong and specific interactions and demonstrate
the important role of Lys802 in the design of novel PI3Kα inhibitors.
PI3K; PI103; crystal structure; drug
design; cancer therapy
Mycosis fungoides (MF) is a cutaneous T-cell lymphoma (CTCL) characterized by neoplastic skin-homing T cells. To better understand the immunopathogenesis of MF, we analyzed the functional ability of peripheral blood mononuclear cells (PBMC) from early and late MF/CTCL patients to express cytokine genes. In late stage MF/CTCL, patients were separated into those with blood involvement (+B) and without blood involvement (−B).
We analyzed TH1 (interleukin 2 (IL-2), IFN-γ), TH2 (IL-4, IL-5, IL-10, IL-13), and TH17 (IL-17) cytokine gene expression from activated PBMCs from normal (n = 12), psoriasis (n = 6), early MF/CTCL (n = 11), and late MF/CTCL+B (n = 4) and MF/CTCL-B (n = 3) by quantitative real-time PCR.
PBMCs from early MF/CTCL and psoriasis showed higher induction of IL-2, IL-4, and IFN-γ genes than those from normal and late MF/CTCL-B and MF/CTCL+B (P < 0.05) in descending order. PBMCs from late MF/CTCL-B exhibited generally the highest level of IL-5, IL-10, IL-13, and IL-17 expression compared with the other groups. PBMCs from early MF/CTCL and late MF/CTCL−B had similarly elevated IL-13 and IL-17. Of all groups, PBMCs from late MF/CTCL+B had the lowest levels of IL-2 (P < 0.05), IL-4, IFN-γ, IL-13, and IL-17.
The different pattern of cytokine gene expression suggests a change in immune function in MF/CTCL from early MF/CTCL to late MF/CTCL−B to late MF/CTCL+B. These stages are consistent with localized disease associated with an anti-tumor immune response and late MF/CTCL associated with a loss of immune function mediated by malignant T cells that share regulatory T cell – like properties.
Precise regulation of mtDNA transcription and oxidative phosphorylation (OXPHOS) is crucial for human health. As a component of mitochondrial contact site and cristae organizing system (MICOS), Mic60 plays a central role in mitochondrial morphology. However, it remains unclear whether Mic60 affects mitochondrial transcription. Here, we report that Mic60 interacts with mitochondrial transcription factors TFAM and TFB2M. Furthermore, we found that Mic60 knockdown compromises mitochondrial transcription and OXPHOS activities. Importantly, Mic60 deficiency decreased TFAM binding and mitochondrial RNA polymerase (POLRMT) recruitment to the mtDNA promoters. In addition, through mtDNA immunoprecipitation (mIP)-chromatin conformation capture (3C) assays, we found that Mic60 interacted with mtDNA and was involved in the architecture of mtDNA D-loop region. Taken together, our findings reveal a previously unrecognized important role of Mic60 in mtDNA transcription.
MicroRNAs (miRNAs) have become the focus of most recent efforts in cancer research. However, there have been inconsistencies in the literature regarding the suitability of circulating miRNAs for early detection of gastrointestinal cancers. This study aims to assess the diagnostic performance of circulating miRNAs in detection of gastrointestinal cancer through a meta-analysis.
Eligible studies were selected by conducting a systematic literature search of public databases. The sensitivity and specificity were used to plot the summary receiver operator characteristic (SROC) curve and calculate the area under the SROC curve (AUC). The between-study heterogeneity was evaluated by Q test and I2 statistics. Subgroup analyses and meta-regression were further performed to explore the potential sources of heterogeneity. All analyses were performed using the STATA 12.0 software.
A total of 107 studies from 42 articles were included for the meta-analysis according to the inclusion criteria. The overall analysis of all gastrointestinal cancers showed that circulating miRNAs have a relatively good diagnostic performance in gastrointestinal cancers, with a sensitivity of 0.75, a specificity of 0.81 and an AUC of 0.85. In addition, subgroup analyses based on different type of miRNA assay suggested that single-miRNA assay displayed a relatively low diagnostic performance with the AUC values of 0.84 for gastric cancer (GC) and 0.79 for colorectal cancer (CRC), while multiple-miRNAs assay significantly improved the diagnosing accuracy with AUC rising to 0.92 for GC and 0.89 for CRC. Another interesting finding was that plasma-based miRNA assay reach a higher accuracy compared with serum-based one for GC, while opposite conclusion was drawn for CRC.
In conclusion, circulating miRNAs, particularly the combination of multiple miRNAs, may present as promising biomarkers for the diagnosis of gastrointestinal cancers. Further large-scale prospective studies are necessary to validate their potential applicability in human cancer diagnosis.
Mothers are important to all humans. Research has established that maternal information affects individuals' cognition, emotion, and behavior. We measured event-related potentials (ERPs) to examine attentional and evaluative processing of maternal stimuli while participants completed a Go/No-go Association Task that paired mother or others words with good or bad evaluative words. Behavioral data showed that participants responded faster to mother words paired with good than the mother words paired with bad but showed no difference in response to these others across conditions, reflecting a positive evaluation of mother. ERPs showed larger P200 and N200 in response to mother than in response to others, suggesting that mother attracted more attention than others. In the subsequent time window, mother in the mother + bad condition elicited a later and larger late positive potential (LPP) than it did in the mother + good condition, but this was not true for others, also suggesting a positive evaluation of mother. These results suggest that people differentiate mother from others during initial attentional stage, and evaluative mother positively during later stage.
Combination antiretroviral therapy (cART) containing rilpivirine plus 2 NRTIs are effective antiretroviral (ARV) regimens for ARV-naive HIV-infected patients who had baseline plasma HIV RNA load (PVL) <5 log10 copies/mL and as switch therapy for those with viral suppression. In this study, we aimed to assess the short-term safety of rilpivirine-containing regimens among HIV-infected patients who initiated or switched to rilpivirine plus two NRTIs in Taiwan.
Materials and Methods
Between January and June 2014, medical records of all HIV-infected patients who initiated or switched to rilpivirine plus two NRTIs, during the follow-up were reviewed to assess the tolerance and adverse effects. Using a standardized data collection form, we recorded data of PVL and CD4 count, serologies for hepatitis B and C virus (HBV and HCV, respectively), haemogram, aminotransferases, bilirubin and serum creatinine before starting rilpivirine-containing regimens at four weeks and every 12 weeks thereafter.
During the study period, medical records of 246 patients initiated their first ARV therapy with rilpivirine-containing regimens (n=90) or switched to rilpivirine-containing regimen from other regimens (156). Of the 246 patients, 73.4% were men who have sex with men and 9.1% and 25.6% tested positive for HBsAg and anti-HCV antibody, respectively. Baseline CD4 was 395 cells/mm3 (range, 2-1581) and PVL, 2.76 log10 copies/mL (range, <1.3>7.0 log10 copies/mL). As of 10 July, 23 patients (9.3%) stopped rilpivirine-containing regimens due to gastrointestinal upset (n=4), skin rash (2), depression (2), poor sleep (3), anaemia (4, all being with zidovudine/lamivudine), nail hyperpigmentation (1), presence of transmitted drug resistance (4), and elevated aminotransferase levels (1). The proportion of the patients with aminotransferases of fivefold or higher than the upper limit of normal (ULN) was 1.7% and 1.5% for AST and ALT, respectively, before starting rilpivirine-containing regimens; the respective value was 1.4% and 2.4% after 12 weeks of cART.
Rilpivirine-containing regimens were generally well tolerated and less than 10% of the patients had to stop rilpivirine due to various reasons. Despite a higher prevalence of chronic HBV or HCV infection, rilpivirine-containing regimens did not cause significant changes of aminotransferases from baseline.
The incidence of recent hepatitis C virus infection (HCV) infection has been noted to be increasing among men who have sex with men (MSM), especially those with HIV infection, in several resource-rich settings. In Taiwan, the incidence of recent HCV infection increased from 0 in 1994–2000, 2.29 in 2001–2005 to 10.13 per 1000 person-years of follow-up (PYFU) in 2006–2010. In this study, we aimed to estimate the incidence rate of recent HCV infection among those individuals who sought voluntary counselling and testing (VCT) service at a University Hospital.
Between May 2006 and December 2013, 18,246 tests for HIV antibody were performed among 12,143 individuals at the VCT services. A total of 2157 clients without HIV or HCV infection at baseline were included for estimation of incidence rate of recent HCV infection. Antibodies to HCV were determined with a third-generation enzyme immunoassay. A nested case-control study with four matched controls without HCV seroconversion for one HCV seroconverter was conducted to investigate the factors associated with recent HCV infection. Phylogenetic analysis was performed among the HCV strains obtained from VCT clients and patients coinfected with HIV and HCV between 2006 and 2013.
During the study period, 2157 clients received a total of 8260 tests. The HCV seroprevalence at baseline was 0.3%. Of the 2150 HCV-negative clients who contributed 5074.99 PYFU, 17 developed HCV seroconversion (incidence rate, 3.35 per 1000 PYFU; 95% CI, 1.76–4.94); the rate increased from 2.28 per 1000 PYFU (95% CI, 0.05–4.51) in 2006–2009, to 3.33 per 1000 PYFU (95% CI, 0.86–5.80) in 2010–2011, to 4.94 per 1000 PYFU (95% CI, 0.99–8.99) in 2012–2013. In case-control study, HCV seroconverters were more likely to have HIV-infected partners, recent syphilis and a Rapid Plasma Reagin (RPR) titre of 4 or greater. In multivariate analysis, having HIV-infected partners remained as the only independent associated factors with HCV seroconversion (AOR, 6.931; 95% CI, 1.064–45.163). Phylogenetic analysis revealed transmission pairs and clusters, with most clustered sequences derived from MSM.
Similar to the observation among HIV-infected patients who are not IDUs, increasing trends of recent HCV infection also occur among the individuals who sought VCT services in Taiwan. Having HIV-infected partners is independently associated with recent HCV seroconversion.
Wide inter-patient variation of plasma efavirenz (EFV) concentrations has been observed, and a substantial proportion of HIV-positive patients may have unnecessarily higher plasma EFV concentrations than recommended while receiving EFV-containing combination antiretroviral therapy (cART) at the currently recommended daily dose of 600 mg. A lower daily dose (400 mg) of EFV has recently been demonstrated to be as efficacious as the recommended 600 mg when combined with tenofovir/mtricitabine in a multinational clinical trial, with a lower incidence of adverse effects. We aimed to use a therapeutic drug monitoring (TDM)-guided strategy to optimize the EFV dose in HIV-positive Taiwanese patients.
Materials and Methods
The plasma EFV concentrations at 12 hours (C12) after taking the previous dose were determined among HIV-positive adults who had received EFV-containing cART with viral suppression (plasma HIV RNA load (PVL) <200 copies/mL). For those with EFV C12 >2.0 mg/L, EFV (Stocrit, MSD) was reduced to half a tablet daily. Determinations of EFV C12 were repeated 4–12 weeks after switch using high-performance liquid chromatography. CYP2B6 G516T polymorphisms were determined using polymerase-chain-reaction restriction fragment-length polymorphism.
Between April 2013 and June 2014, 111 patients (95.5% male; mean age, 39 years; 96.4% with PVL <40 copies/ml; 26.4% HBsAg-positive and 7.5% anti-HCV-positive) with plasma C12 efavirenz >2.0 mg/L were switched to a reduced dose (1/2# hs) of EFV; 45.5% of them had CYP2B6 G516T or TT genotypes; and 32.4% weighed 60 kg or less. The mean baseline EFV C12 before switch was 3.65 mg/L (interquartile range (IQR), 2.62–4.17) for 111 patients, which decreased to 1.96 mg/L (IQR, 1.53–2.33) for 64 patients who had completed follow-up of C12 EFV 4 weeks after switch, with a reduction of 49.4% (IQR, 38.9–57.0%). As of 10 July, 2014, all of the 38 patients (100%) who had completed at least one follow-up of PVL achieved undetectable PVL (<40 copies/ml) following switch to a reduced dose of EFV after a mean observation of 13 weeks (IQR, 7–15 weeks).
Switch to cART containing a half tablet of EFV (1/2#) in HIV-positive Taiwanese patients with higher plasma EFV concentrations who had achieved viral suppression could maintain successful viral suppression with the guidance of TDM.
The total case number of persons who are newly diagnosed with HIV continues to increase in Taiwan and men who have sex with men (MSM) have re-emerged as the leading risk group for HIV transmission. In this study, we aimed to estimate the incidence rate of HIV infection among those individuals who sought voluntary counselling and testing (VCT) service at a university hospital.
Between 1 April, 2006 and 31 December, 2013, 18,246 tests for HIV antibody were performed among 12143 individuals at the VCT service. A total of 2157 individuals who tested negative for anti-HIV antibody had subsequent follow-up tests at the same VCT service, which composed the study population for estimation of incidence rate of recent HIV infection. The BED assays were used to identify recent HIV infections that occurred within the previous six months before seeking VCT service.
During the 6.5-year study period, 647 individuals were diagnosed as being HIV-positive, with an overall HIV seroprevalence of 3.55% (95% CI 3.27–3.82). The overall incidence rate of HIV infection was estimated 4.13 per 100 person-years of follow-up (95% CI 3.67–4.69 per 100 person-years of follow-up). MSM had an estimated 10-fold higher seroprevalence and seroincidence of HIV than heterosexuals. Of 647 clients testing positive for HIV, 603 clients were MSM (93.2%) and 477 patients (70.8%) subsequently sought HIV care at the hospital; 226 (47.4%) were diagnosed as having recent HIV infections by the BED assay, while 244 (51.2%) long-term infection and 7 without data by the BED assay. Of those patients, 173 (75.6%) and 178 patients (73.0%) with recent HIV infection and long-term infection had data of transmitted drug resistance mutations, respectively. The prevalence of transmitted drug resistance mutations to any class of antiretroviral therapy was 9.0% and 10.6% (p=0.68), respectively, of the HIV-1 strains from the patients with recent HIV infection and long-term infection, respectively.
The seroincidence rate of HIV among persons seeking VCT was estimated 4.13 per 100 person-years of follow-up. The prevalence of transmitted drug resistance to any class of antiretroviral agents was similar between those who were recently infected with HIV and those who had long-term infection in Taiwan.
This retrospective study aimed to investigate that if switch of combination antiretroviral therapy (cART) would result in viral suppression (<40 copies/mL) at 48 weeks for patients with persistent low-level viremia after having received cART for six months or more at two hospitals designated for HIV care in Taiwan.
Materials and Methods
Between January 2001 and January 2013, patients were enrolled if plasma HIV RNA load (PVL) were >20 to <1000 copies/mL detected for six months or more [1, 2]. Using a standardized data collection form, we recorded data of PVL and CD4 count before cART and at the detection of low-level viremia, serologies for hepatitis B and C virus, risk factors, duration of cART exposure, years of HIV diagnosed and ever experiencing treatment failure. The strategy of switch is based on the clinical guidelines of BHIVA, which suggest change of cART from non-nucleoside reverse-transcriptase inhibitors (nNRTIs) or unboosted protease inhibitor (PI) to boosted PI, newer boosted PI or ARV of different mechanism .
In this study, 165 patients were enrolled, 119 patients (72.1%) did not switch (Group 1), and 46 patients (27.9%) switched previous regimens to ARV of different mechanism (Group 2). The two groups differed significantly in the proportion of injecting drug users (IDU) (Group 1 vs Group 2, 10.9 vs 26.1%) and median PVL (67 vs 159 copies/mL), and the proportion of PVL<200 copies/mL (84.0% vs 58.7%) when low-level viremia was first detected. In Group 1, 39 (32.8%) continued two nucleoside reverse-transcriptase inhibitors (NRTIs) plus nNRTI; 29 (24.4%) 2 NRTIs plus PI, 47 (39.5%) 2 NRTIs plus boosted PI, and 4 (3.3%) 2 NRTIs plus integrase inhibitor (II). In Group 2, two (4.3%) switched to 2 NRTIs plus PI, 38 (82.6%) 2 NRTIs plus boosted PI, three (6.5%) 2 NRTIs plus II and three (6.5%) boosted PI plus II. In multivariate analysis, IDUs (adjusted odds ratio [AOR], 6.757; 95% CI 2.427–18.868) and PVL of 200–999 copies/mL at enrollment (AOR, 4.902; 95% CI 1.992–12.048) were more likely to be switched. At 48 weeks, patients in Group 2 were more likely to achieve PVL<40 copies/mL than Group 1 (82.6% vs 63.0%, p=0.016), while no difference was observed in achieving PVL <200 copies/mL between the two groups (95.7% vs 92.4%, p=0.729).
According to the clinical guidelines of BHIVA, patients with low-level viremia who switched to cART consisting of 2 NRTIs plus boosted PI or newer mechanisms were more likely to re-establish viral suppression to <40 copies/mL at week 48.
Bradykinin-related peptides (BRPs) are significant components of the defensive skin secretions of many anuran amphibians, and these secretions represent the source of the most diverse spectrum of such peptides so far encountered in nature. Of the many families of bioactive peptides that have been identified from this source, the BRPs uniquely appear to represent homologues of counterparts that have specific distributions and receptor targets within discrete vertebrate taxa, ranging from fishes through mammals. Their broad spectra of actions, including pain and inflammation induction and smooth muscle effects, make these peptides ideal weapons in predator deterrence. Here, we describe a novel 12-mer BRP (RVALPPGFTPLR-RVAL-(L1, T6, L8)-bradykinin) from the skin secretion of the Fujian large-headed frog (Limnonectes fujianensis). The C-terminal 9 residues of this BRP (-LPPGFTPLR) exhibit three amino acid substitutions (L/R at Position 1, T/S at Position 6 and L/F at Position 8) when compared to canonical mammalian bradykinin (BK), but are identical to the kinin sequence present within the cloned kininogen-2 from the Chinese soft-shelled turtle (Pelodiscus sinensis) and differ from that encoded by kininogen-2 of the Tibetan ground tit (Pseudopodoces humilis) at just a single site (F/L at Position 8). These data would imply that the novel BRP is an amphibian defensive agent against predation by sympatric turtles and also that the primary structure of the avian BK, ornithokinin (RPPGFTPLR), is not invariant within this taxon. Synthetic RVAL-(L1, T6, L8)-bradykinin was found to be an antagonist of BK-induced rat tail artery smooth muscle relaxation acting via the B2-receptor.
amphibian; skin secretion; molecular cloning; bradykinin; smooth muscle
Considering the characterization of vitamin D deficiency as a risk factor of ectopic fat deposition, the association of serum 25-hydroxy vitamin D3 [25(OH)D3] levels with non-alcoholic fatty liver disease (NAFLD) was evaluated in Chinese men with normal body mass index (BMI) and enzyme markers of liver function.
A total of 514 participants (22 to 79 years old) with normal BMI and liver enzymes were identified for analysis. Abdominal ultrasound was performed to diagnose NAFLD, and the fatty liver index (FLI) was calculated to quantify liver steatosis. Serum 25(OH)D3 levels were determined by an electrochemiluminescence immunoassay.
Among the entire study population, the mean levels of serum 25(OH)D3 were 15.32±5.77 ng/mL. However, when serum 25(OH)D3 levels were compared between non-NAFLD subjects (n=438) and NAFLD subjects (n=76), the latter showed significantly lower levels (15.65±5.89 ng/mL vs 13.46±4.65 ng/mL, P=0.002). In addition, serum 25(OH)D3 levels were found to be significantly correlated with FLI after adjustment for age and BMI (r=−0.108, P=0.014). Logistic regression showed that serum 25(OH)D3 levels were independently correlated with NAFLD (OR: 0.937, 95% CI: 0.884–0.993, P=0.028). Furthermore, stepwise regression analysis revealed that serum 25(OH)D3 levels were inversely associated with FLI (β=−0.055, P=0.040).
The present study demonstrated that serum 25(OH)D3 levels were inversely associated with NAFLD, even in subjects with normal total body fat, suggesting a potential role of lower levels of vitamin D in the occurrence and development of NAFLD.
25-hydroxy vitamin D3; non-alcoholic fatty liver disease; fatty liver index
With the widespread use of combination antiretroviral therapy (cART), life expectancy of HIV-infected patients has significantly prolonged. An increasing number of HIV-infected patients are aging and concurrent use of medications are not uncommon for management of metabolic complications and cardiovascular diseases related to aging and prolonged exposure to cART.
We reviewed medical records of all HIV-infected patients aged 40 years or older who had been followed at a university hospital for HIV care in Taiwan between January and December 2013. A standardized case record form was used to collect information on demographics and clinical characteristics, comorbidity, cART, and concurrent medications.
During the study period, 610 patients aged 40 to 49 years (mean, 44.1) and 310 aged 50 years or older (mean, 58.8) sought HIV care at this hospital. Compared with patients aged 40 to 49 years, those aged 50 years or older were significantly more likely to be female (15.9% vs 3.8%); to have received cART (97.7% vs 94.8%) and a lower plasma HIV RNA load (1.6 vs 1.7 log10 copies/ml); and to have diabetes mellitus (18.4% vs 4.6%), hypertension (31.0% vs 10.8%), hyperlipidemia (29.4% vs 11.6%), coronary artery disease (6.8% vs 0.5%), and an estimated glomerular filtration rate <60 ml/min/1.73 m2 (11.5% vs 2.7%); and were significantly less likely to have syphilis. Other than HIV infection, patients aged 50 years or older were more likely to have been receiving two or more concurrent medications than those aged 40 to 49 years (22.9% vs 6.4%).
Our findings show a significant proportion of the HIV-infected patients aged 50 years or older have multiple comorbidities that may increase the risk for cardiovascular and renal complications. Issues of poly-pharmacy among the HIV-infected patients who are aging should be addressed to ensure adherence and minimize drug-drug interactions.
Behavioral research has established that humans implicitly tend to hold a positive view toward themselves. In this study, we employed the event-related potential (ERP) technique to explore neural manifestations of positive implicit self-esteem using the Go/Nogo association task (GNAT). Participants generated a response (Go) or withheld a response (Nogo) to self or others words and good or bad attributes. Behavioral data showed that participants responded faster to the self paired with good than the self paired with bad, whereas the opposite proved true for others, reflecting the positive nature of implicit self-esteem. ERP results showed an augmented N200 over the frontal areas in Nogo responses relative to Go responses. Moreover, the positive implicit self-positivity bias delayed the onset time of the N200 wave difference between Nogo and Go trials, suggesting that positive implicit self-esteem is manifested on neural activity about 270 ms after the presentation of self-relevant stimuli. These findings provide neural evidence for the positivity and automaticity of implicit self-esteem.
Purpose: Abnormal global DNA methylation levels are associated with many diseases. In this study, we examined long interspersed nuclear elements-1 (LINE-1) methylation as a biomarker for abnormal global DNA methylation and aldosterone-producing adenoma (APA). Methods: Tissues from 25 APA and 6 normal adrenal glands (NAs) were analyzed for LINE-1 methylation by real-time methylation-specific polymerase chain reaction. The estimated LINE-1 methylation level was then tested for correlation with the clinicopathologic parameters of APA patients. Results: The methylation index (MI) level for LINE-1 was 0.91 in NA samples and 0.77 in APA samples (P < 0.001). For the APA samples, there were no statistical correlations between the MI level and various clinicopathologic parameters such as gender (P = 0.07). Conclusion : LINE-1 methylation is significantly lower in APA samples than in NA samples. LINE-1 methylation is not correlated with the clinical characteristics of APA.
Long interspersed nuclear elements-1; global DNA methylation; aldosterone-producing adenoma
The first amphibian skin antimicrobial peptide (AMP) to be identified was named bombinin, reflecting its origin from the skin of the European yellow-bellied toad (Bombina variegata). Bombinins and their related peptides, the bombinin Hs, were subsequently reported from other bombinid toads. Molecular cloning of bombinin-encoding cDNAs from skin found that bombinins and bombinin Hs were coencoded on the same precursor proteins. Here, we report the molecular cloning of two novel cDNAs from a skin secretion-derived cDNA library of B. variegata whose open-reading frames each encode a novel bombinin (GIGGALLNVGKVALKGLAKGLAEHFANamide) and a C-terminally located single copy of a novel nonapeptide (FLGLLGGLLamide or FLGLIGSLLamide). These novel nonapeptides were named feleucin-BV1 and feleucin-BV2, respectively. The novel bombinin exhibited 89% identity to homologues from the toads, B. microdeladigitora and B. maxima. The feleucins exhibited no identity with any amphibian AMP archived in databases. Synthetic feleucins exhibited a weak activity against Staphylococcus aureus (128–256 mg/L) but feleucin-BV1 exhibited a synergistic action with the novel bombinin. The present report clearly demonstrates that the skin secretions of bombinid toads continue to represent a source of peptides of novel structure that could provide templates for the design of therapeutics.
The roles of oxidative stress on nuclear factor (NF)-κB activity and cardiomyocyte apoptosis during heart failure were examined using the antioxidant N-acetylcysteine (NAC). Heart failure was established in Japanese white rabbits with intravenous injections of doxorubicin, with ten rabbits serving as a control group. Of the rabbits with heart failure, 12 were not treated (HF group) and 13 received NAC (NAC group). Cardiac function was assessed using echocardiography and hemodynamic analysis. Myocardial cell apoptosis, apoptosis-related protein expression, NF-κBp65 expression and activity, total anti-oxidative capacity (tAOC), 8-iso-prostaglandin F2α (8-iso-PGF2α) expression and glutathione (GSH) expression levels were determined. In the HF group, reduced tAOC, GSH levels and Bcl-2/Bax ratios as well as increased 8-iso-PGF2α levels and apoptosis were observed (all P<0.05), which were effects that were attenuated by the treatment with NAC. NF-κBp65 and iNOS levels were significantly higher and the P-IκB-α levels were significantly lower in the HF group; expression of all three proteins returned to pre-HF levels following treatment with NAC. Myocardial cell apoptosis was positively correlated with left ventricular end-diastolic pressure (LVEDP), NF-κBp65 expression and 8-iso-PGF2α levels, but negatively correlated with the maximal and minimal rates of increase in left ventricular pressure (+dp/dtmax and −dp/dtmin, respectively) and the Bcl-2/Bax ratio (all P<0.001). The 8-iso-PGF2α levels were positively correlated with LVEDP and negatively correlated with +dp/dtmax and −dp/dtmin (all P<0.001). The present study demonstrated that NAC increased the antioxidant capacity, decreased the NF-κB activation and reduced myocardial cell apoptosis in an in vivo heart failure model.
N-acetylcysteine; nuclear factor κ B; heart failure; apoptosis; reactive oxygen species
D-alanylation of the lipoteichoic acid on Gram-positive cell wall is dependent on
dlt gene-encoded proteins DltA, DltB, DltC and DltD. The D-alanyl carrier protein ligase DltA, as a remote homolog of acyl-(coenzyme A) (CoA) synthetase, cycles through two active conformations for the catalysis of adenylation and subsequent thiolation of D-alanine (D-Ala). The crystal structure of DltA in the absence of any substrate was observed to have a noticeably more disordered pocket for ATP which would explain why DltA has relatively low affinity for ATP in the absence of any D-alanyl carrier. We have previously enabled the thiolation of D-alanine in the presence of CoA as the mimic of D-alanyl carrier protein DltC which carries a 4’-phosphopantetheine group on a serine residue. Here we show that the resulting Michaelis constants in the presence of saturating CoA for both ATP and D-alanine were reduced more than 10 fold as compared to the values obtained in the absence of CoA. The presence of CoA also made DltA ~100-fold more selective on D-alanine over L-alanine. The CoA-enhanced substrate recognition further implies that the ATP and D-alanine substrates of the adenylation reaction are incorporated when the DltA enzyme cycles through its thiolation conformation.
Mitochondria are perhaps the most sophisticated and dynamic responsive sensing systems in eukaryotic cells. The role of mitochondria goes beyond their capacity to create molecular fuel and includes the generation of reactive oxygen species, the regulation of calcium, and the activation of cell death. In endothelial cells, mitochondria have a profound impact on cellular function under both healthy and diseased conditions. In this review, we summarize the basic functions of mitochondria in endothelial cells and discuss the roles of mitochondria in endothelial dysfunction and vascular diseases, including atherosclerosis, diabetic vascular dysfunction, pulmonary artery hypertension, and hypertension. Finally, the potential therapeutic strategies to improve mitochondrial function in endothelial cells and vascular diseases are also discussed, with a focus on mitochondrial-targeted antioxidants and calorie restriction.
mitochondria; endothelial cell; atherosclerosis; diabetes mellitus; pulmonary artery hypertension; hypertension; antioxidants; caloric restriction
Zinc-α2-glycoprotein (ZAG) has been proposed to play a role in the pathogenesis of insulin resistance. Previous studies in humans and in rodents have produced conflicting results regarding the link between ZAG and insulin resistance. The objective of this study was to examine the relationships between ZAG and insulin resistance in cross-sectional and interventional studies.
RESEARCH DESIGN AND METHODS
Serum ZAG (determined with ELISA) was compared with various parameters related to insulin resistance in subjects with normal glucose tolerance, impaired glucose tolerance (IGT), and newly diagnosed type 2 diabetes mellitus (T2DM), and in women with or without polycystic ovary syndrome (PCOS). Euglycemic-hyperinsulinemic clamps were performed in healthy and PCOS women. Real-time RT-PCR and Western blotting were used to assess mRNA and protein expression of ZAG. The effect of a glucagon-like peptide-1 agonist on ZAG was studied in a 12-week liraglutide treatment trial.
Circulating ZAG was lower in patients with IGT and newly diagnosed T2DM than in controls. Circulating ZAG correlated positively with HDL cholesterol and adiponectin, and correlated inversely with BMI, waist-to-hip ratio, body fat percentage, triglycerides, fasting blood glucose, fasting insulin, HbA1c, and homeostasis model assessment of insulin resistance (HOMA-IR). On multivariate analysis, ZAG was independently associated with BMI, HOMA-IR, and adiponectin. ZAG mRNA and protein were decreased in adipose tissue of T2DM patients. Moreover, circulating ZAG levels were lower in women with PCOS than in women with high insulin sensitivity. Liraglutide treatment for 12 weeks significantly increased circulating ZAG levels.
We conclude that ZAG may be an adipokine associated with insulin resistance.
Pediatric emergency care medicine is an important field of health care. This study aimed to investigate the 10-year pediatric emergency care in children aged 0-17 years old in Taiwan.
Systematic random samples from the National Health Insurance Research Database of Taiwan in the period 2000-2009 were analyzed. Children recorded as undergoing emergency care were enrolled and divided into different age groups. The frequency of emergency visits, age, cost per visit, seasonality, number of hospitalizations, and diagnosis were analyzed.
A total of 764,598 children were enrolled. These children accounted for 25% of all emergency cases and their mean age was 6.1 years. Children aged 0-5 years formed the largest group, with male predominance (57.5%). The incidence of emergency visits was 29133 ± 3104 per 100,000 children per year (mean ± SD). Acute upper airway infection, fever, and acute gastrointestinal illness were the most common diagnoses among all non-hospitalized children. Some (4.51%) required subsequent hospitalization and their most common diagnoses were fluid/electrolyte disorder, upper/lower airway infection, and acute gastrointestinal illness. The group of children aged 12-17 years had cases of traumatic injury and childbirth.
In Taiwan, 25% of individuals seeking emergency care are children, mostly aged 0-5 years old. Costs and disease patterns vary among different age groups. Preventive measures targeting all children should focus on respiratory and gastrointestinal diseases, but should target different diseases for different age groups to improve child health.
Children; Emergency; Hospitalization; National health insurance research database
The defensive skin secretions of many amphibians are a rich source of bradykinins and bradykinin-related peptides (BRPs). Members of this peptide group are also common components of reptile and arthropod venoms due to their multiple biological functions that include induction of pain, effects on many smooth muscle types, and lowering systemic blood pressure. While most BRPs are bradykinin receptor agonists, some have curiously been found to be exquisite antagonists, such as the maximakinin gene-related peptide, kinestatin—a specific bradykinin B2-receptor antagonist from the skin of the giant fire-bellied toad, Bombina maxima. Here, we describe the identification, structural and functional characterization of a heptadecapeptide (DYTIRTRLHQGLSRKIV), named ranakinestatin-PPF, from the skin of the Chinese ranid frog, Pelophylax plancyi fukienensis, representing a prototype of a novel class of bradykinin B2-receptor specific antagonist. Using a preconstricted preparation of rat tail arterial smooth muscle, a single dose of 10−6 M of the peptide effectively inhibited the dose-dependent relaxation effect of bradykinin between 10−11 M and 10−5 M and subsequently, this effect was pharmacologically-characterized using specific bradykinin B1- (desArg-HOE140) and B2-receptor (HOE140) antagonists; the data from which demonstrated that the antagonism of the novel peptide was mediated through B2-receptors. Ranakinestatin—PPF—thus represents a prototype of an amphibian skin peptide family that functions as a bradykinin B2-receptor antagonist herein demonstrated using mammalian vascular smooth muscle.
Narcissism, characterized by grandiose self-image and entitled feelings to others, has been increasingly prevalent in the past decades. This study examined genetic and environmental bases of two dimensions of narcissism: intrapersonal grandiosity and interpersonal entitlement. A total of 304 pairs of twins from Beijing, China completed the Narcissistic Grandiosity Scale and the Psychological Entitlement Scale. Both grandiosity (23%) and entitlement (35%) were found to be moderately heritable, while simultaneously showing considerable non-shared environmental influences. Moreover, the genetic and environmental influences on the two dimensions were mostly unique (92–93%), with few genetic and environmental effects in common (7–8%). The two dimensions of narcissism, intrapersonal grandiosity and interpersonal entitlement, are heritable and largely independent of each other in terms of their genetic and environmental sources. These findings extend our understanding of the heritability of narcissism on the one hand. On the other hand, the study demonstrates the rationale for distinguishing between intrapersonal and interpersonal dimensions of narcissism, and possibly personality in general as well.
Implicit self-esteem has remained an active research topic in both the areas of implicit social cognition and self-esteem in recent decades. The purpose of this study is to explore the development of implicit self-esteem in adolescents. A total of 599 adolescents from junior and senior high schools in East China participated in the study. They ranged in age from 11 to 18 years with a mean age of 14.10 (SD = 2.16). The degree of implicit self-esteem was assessed using the Implicit Association Test (IAT) with the improved D score as the index. Participants also completed the Rosenberg Self-Esteem Scale (α = 0.77). For all surveyed ages, implicit self-esteem was positively biased, all ts>8.59, all ps<0.001. The simple correlation between implicit self-esteem and age was significant, r = −.25, p = 1.0×10−10. A regression with implicit self-esteem as the criterion variable, and age, gender, and age × gender interaction as predictors further revealed the significant negative linear relationship between age and implicit self-esteem, β = −0.19, t = −3.20, p = 0.001. However, explicit self-esteem manifested a reverse “U” shape throughout adolescence. Implicit self-esteem in adolescence manifests a declining trend with increasing age, suggesting that it is sensitive to developmental or age-related changes. This finding enriches our understanding of the development of implicit social cognition.
Key Clinical Message
Cockayne syndrome (CS) is a rare autosomal recessive genetic disease characterized by growth failure and progressive neurological degeneration. Here we report a mild form of CS patient who was homozygous for the C526T transition resulting in a new nonsense mutation, which converts Arg176 to a stop codon.
Cockayne syndrome; CSB gene; mutation