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Phase 1/2a Trial of Plasmodium vivax Malaria Vaccine Candidate VMP001/AS01B in Malaria-Naive Adults: Safety, Immunogenicity, and Efficacy. - PLoS neglected tropical diseases
A vaccine to prevent infection and disease caused by Plasmodium vivax is needed both to reduce the morbidity caused by this parasite and as a key component in efforts to eradicate malaria worldwide. Vivax malaria protein 1 (VMP001), a novel chimeric protein that incorporates the amino- and carboxy- terminal regions of the circumsporozoite protein (CSP) and a truncated repeat region that contains repeat sequences from both the VK210 (type 1) and the VK247 (type 2) parasites, was developed as a vaccine candidate for global use.We conducted a first-in-human Phase 1 dose escalation vaccine study with controlled human malaria infection (CHMI) of VMP001 formulated in the GSK Adjuvant System AS01B. A total of 30 volunteers divided into 3 groups (10 per group) were given 3 intramuscular injections of 15Î¼g, 30Î¼g, or 60Î¼g respectively of VMP001, all formulated in 500Î¼L of AS01B at each immunization. All vaccinated volunteers participated in a P. vivax CHMI 14 days following the third immunization. Six non-vaccinated subjects served as infectivity controls.The vaccine was shown to be well tolerated and immunogenic. All volunteers generated robust humoral and cellular immune responses to the vaccine antigen. Vaccination did not induce sterile protection; however, a small but significant delay in time to parasitemia was seen in 59% of vaccinated subjects compared to the control group. An association was identified between levels of anti-type 1 repeat antibodies and prepatent period.This trial was the first to assess the efficacy of a P. vivax CSP vaccine candidate by CHMI. The association of type 1 repeat-specific antibody responses with delay in the prepatency period suggests that augmenting the immune responses to this domain may improve strain-specific vaccine efficacy. The availability of a P. vivax CHMI model will accelerate the process of P. vivax vaccine development, allowing better selection of candidate vaccines for advancement to field trials.
Antidepressant treatment and risk of dementia: a population-based, retrospective case-control study. - The Journal of clinical psychiatry
We investigated the relationship between antidepressant use and the risk of subsequent dementia development.A population-based retrospective case-control analysis was conducted using the Taiwan National Health Insurance Research Database. From patients enrolled in the National Health Insurance program between 2005 and 2011, we identified 2 subsets: 5,394 cases, who had major depression in 1997-2004 and subsequently were diagnosed with dementia (ICD-9-CM code 290) in 2005-2011, and 5,232 controls, who had major depression in 2005-2011 but no dementia history. The proportional distributions of antidepressant use and comorbidities in the dementia case and nondementia control groups were compared. Univariable and multivariable logistic regression analyses were used to estimate the odds ratios (ORs) and 95% CIs for the association between dementia and antidepressant use.The dementia patients were more likely to have diabetes, hypertension, stroke, and head injury. The adjusted OR for dementia was 0.24 (95% CI, 0.22-0.27) in patients using tricyclics . By contrast, the use of selective serotonin reuptake inhibitors (SSRIs) (OR = 2.48; 95% CI, 2.27-2.71), monoamine oxidase inhibitors (MAOIs) (OR = 1.86; 95% CI, 1.47-2.36), heterocyclic antidepressants (OR = 1.44; 95% CI, 1.32-1.57), and other antidepressants (OR = 2.05; 95% CI, 1.85-2.27) was associated with an increased risk of dementia. Furthermore, as the cumulative dose was increased, tricyclic antidepressants reduced the risk of dementia, whereas SSRIs, MAOIs, heterocyclic antidepressants, and other antidepressants increased the risk of dementia.The incidence of dementia in patients is associated with antidepressant medication use. Treatment with tricyclic antidepressants was associated with a reduced risk of dementia, whereas treatment with SSRIs, MAOIs, heterocyclic antidepressants, and other antidepressants was associated with an increased risk of dementia.Â© Copyright 2016 Physicians Postgraduate Press, Inc.
The pharmacokinetics of intraosseous atropine in hypovolemic swine. - American journal of disaster medicine
Compare the pharmacokinetics of atropine administered via the intravenous (IV), intramuscular (IM), and intraosseous (IO) routes in a normovolemic and hypovolemic swine model.Prospective, between subjects, experimental study.Vivarium.Yorkshire-cross swine (N = 36).Atropine was administered via IV, IM, or IO routes to normovolemic and hypovolemic swine. Blood samples were drawn at regular intervals after atropine administration and analyzed for plasma atropine concentration. Pharmacokinetic parameters were obtained from modeling the plasma concentrations.Pharmacokinetic parameters, maximum concentration (Cmax) and time to maximum concentration (Tmax).The IV and IO groups in both the normovolemic and hypovolemic models reached peak plasma concentration immediately and had a very rapid distribution phase with no apparent absorption phase for the IO groups. Peak plasma concentration and time to reach peak concentration were both significantly lower for the IM groups. There was a significant increase in absorption time with IM administration in the hypovolemic model compared to the normovolemic model.The IO route is an effective method of administering atropine and is comparable to the IV route even under conditions of significant hemorrhage. Therapeutic levels of atropine may be delayed and possibly difficult to obtain via IM injection in the presence of hypovolemic shock.
Why and when workplace ostracism inhibits organizational citizenship behaviors: An organizational identification perspective. - The Journal of applied psychology
Why and when do employees respond to workplace ostracism by withholding their engagement in citizenship behavior? Beyond perspectives proposed in past studies, we offer a new account based on a social identity perspective and propose that workplace ostracism decreases citizenship behavior by undermining employees' identification with the organization. We also theorize that perceived job mobility influences the extent to which employees identify with the organization when being ostracized. These hypotheses were examined in two time-lagged studies conducted in China. The proposed hypotheses were supported by results in Study 1, and findings were generally replicated in Study 2, where effects of other known mediators (i.e., organization-based self-esteem, job engagement, and felt obligation toward the organization) and moderators (i.e., collectivism, power distance, and future orientation) suggested by previous perspectives were controlled. Results of Study 2 provided further support of the hypothesized directional effect of workplace ostracism on citizenship behavior via organizational identification. Our studies support the identification perspective in understanding workplace ostracism and also strengthen the application of this perspective in understanding workplace aggression broadly. (PsycINFO Database Record(c) 2016 APA, all rights reserved).
Risk of type 2 diabetes mellitus in female breast cancer patients treated with morphine: A retrospective population-based time-dependent cohort study. - Diabetes research and clinical practice
We aimed to examine whether morphine treatment is associated with type 2 diabetes mellitus (T2DM) in female breast cancer patients.We conducted a retrospective cohort analysis of the Longitudinal Health Insurance Database for Catastrophic Illness Patients in Taiwan. A total of 31,112 women with breast cancer without T2DM history during the period 2000-2005 were identified, divided into morphine and non-morphine users (8071 and 23,041 patients, respectively), and the hazard ratios of newly diagnosed T2DM during the period 2005-2010 were calculated. We used a Cox proportional hazard model with time-dependent exposure covariates to estimate the risk of T2DM. The dosage of morphine was counted as defined daily dose and its effect was assessed by multivariable Cox proportional hazard regression controlling age, Charlson comorbidity index, outpatient department visits, antipsychotics, and breast cancer drugs.Morphine users were 1.24 times more likely to suffer from T2DM than non-morphine users (95% CI=1.04-1.49). Risk increased slightly with the morphine dosage, in patients aged 35-49 years, and with tamoxifen, aromatase inhibitors, and antipsychotics treatment.The incidence of T2DM is associated with morphine treatment in female breast cancer patients. A higher risk was observed in patients aged 35-49 years using higher dose of morphine, and may be increased by tamoxifen and aromatase inhibitors.Copyright Â© 2015 Elsevier Ireland Ltd. All rights reserved.
Increased osteoporosis risk in dermatomyositis or polymyositis independent of the treatments: a population-based cohort study with propensity score. - Endocrine
We investigated the relationship between dermatomyositis/polymyositis (DM/PM) and the risk of subsequent osteoporosis development. A population-based retrospective cohort analysis was conducted using the National Health Insurance Research Database and the Catastrophic Illness Patients Database of Taiwan. We included 1179 patients and 4716 patients from 1999 to 2008 as the DM/PM cohort and the comparison cohort, respectively, and calculated the incidence rates of newly diagnosed osteoporosis. We used Cox proportional hazards models stratified on matched pair to assess the effect of DM/PM. The Kaplan-Meier method was applied to estimate the cumulative osteoporosis incidence curves. Patients with DM/PM were 2.99 times more likely to experience osteoporosis than those without DM/PM. The risk for osteoporosis in DM/PM patients was higher than comparisons in different propensity score quartiles. DM/PM cohort, no matter treated with or without corticosteroids and immunosuppressant, had a higher risk than the comparison cohort. The incidence of osteoporosis in Taiwan is associated with a priori DM/PM history. This risk was independent of the corticosteroids and immunosuppressant treatment.
Buprenorphine-elicited alteration of adenylate cyclase activity in human embryonic kidney 293 cells coexpressing Îº-, Î¼-opioid and nociceptin receptors. - Journal of cellular and molecular medicine
Buprenorphine, a maintenance drug for heroin addicts, exerts its pharmacological function via Îº- (KOP), Î¼-opioid (MOP) and nociceptin/opioid receptor-like 1 (NOP) receptors. Previously, we investigated its effects in an in vitro model expressing human MOP and NOP receptors individually or simultaneously (MOP, NOP, and MOP+NOP) in human embryonic kidney 293 cells. Here, we expanded this cell model by expressing human KOP, MOP and NOP receptors individually or simultaneously (KOP, KOP+MOP, KOP+NOP and KOP+MOP+NOP). Radioligand binding with tritium-labelled diprenorphine confirmed the expression of KOP receptors. Immunoblotting and immunocytochemistry indicated that the expressed KOP, MOP and NOP receptors are N-linked glycoproteins and colocalized in cytoplasmic compartments. Acute application of the opioid receptor agonists- U-69593, DAMGO and nociceptin- inhibited adenylate cyclase (AC) activity in cells expressing KOP, MOP and NOP receptors respectively. Buprenorphine, when applied acutely, inhibited AC activity to ~90% in cells expressing KOP+MOP+NOP receptors. Chronic exposure to buprenorphine induced concentration-dependent AC superactivation in cells expressing KOP+NOP receptors, and the level of this superactivation was even higher in KOP+MOP+NOP-expressing cells. Our study demonstrated that MOP receptor could enhance AC regulation in the presence of coexpressed KOP and NOP receptors, and NOP receptor is essential for concentration-dependent AC superactivation elicited by chronic buprenorphine exposure.Â© 2015 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.
Ad35.CS.01-RTS,S/AS01 Heterologous Prime Boost Vaccine Efficacy against Sporozoite Challenge in Healthy Malaria-NaÃ¯ve Adults. - PloS one
In an observer blind, phase 2 trial, 55 adults were randomized to receive one dose of Ad35.CS.01 vaccine followed by two doses of RTS,S/AS01 (ARR-group) or three doses of RTS,S/AS01 (RRR-group) at months 0, 1, 2 followed by controlled human malaria infection.ARR and RRR vaccine regimens were well tolerated. Efficacy of ARR and RRR groups after controlled human malaria infection was 44% (95% confidence interval 21%-60%) and 52% (25%-70%), respectively. The RRR-group had greater anti-CS specific IgG titers than did the ARR-group. There were higher numbers of CS-specific CD4 T-cells expressing > 2 cytokine/activation markers and more ex vivo IFN-Î³ enzyme-linked immunospots in the ARR-group than the RRR-group. Protected subjects had higher CS-specific IgG titers than non-protected subjects (geometric mean titer, 120.8 vs 51.8 EU/ml, respectively; P = .001).An increase in vaccine efficacy of ARR-group over RRR-group was not achieved. Future strategies to improve upon RTS,S-induced protection may need to utilize alternative highly immunogenic prime-boost regimens and/or additional target antigens.ClinicalTrials.gov NCT01366534.
Depression and risk of venous thromboembolism: a population-based retrospective cohort study. - Psychosomatic medicine
This study investigated the relationship between depression and the risk of subsequent venous thromboembolism (VTE) development.We conducted a population-based retrospective cohort analysis by using data for the period of 2000 to 2011 from the Longitudinal Health Insurance Database 2000 of Taiwan. A depression cohort comprising 35,274 patients and a nondepression cohort comprising 70,548 patients matched according to sex, age, and index year with no history of VTE were evaluated. Cox proportional hazard regression analysis was used to assess the effects of depression and comorbidities, and the Kaplan-Meier method was applied to estimate the cumulative VTE incidence curves.Compared with individuals without depression, depressed patients had a 1.38-fold greater risk (95% confidence interval = 1.09-1.73) of developing VTE. This risk was significantly higher in male and younger (â‰¤49 years) patients. In addition, patients with comorbidities such as hypertension, diabetes, heart failure, and cancer had a higher risk of depression-associated VTE that was attenuated, although nonsignificantly, by antidepressant use.The incidence of VTE in Taiwan is higher in depressed patients than in nondepressed patients. Moreover, men, people 49 years or younger, and patients with comorbidities have a significantly greater risk of VTE after depression.
Job insecurity and organizational citizenship behavior: exploring curvilinear and moderated relationships. - The Journal of applied psychology
This article examined a curvilinear relationship between job insecurity and organizational citizenship behavior (OCB). Drawing from social exchange theory and research on personal control, we developed and tested an explanation for employees' reactions to job insecurity based on their conceptualization of their social exchange relationship with the organization at different levels of job insecurity. Using data from 244 Chinese employees and 102 supervisory ratings of OCB, we found support for a U-shaped relationship between job insecurity and OCB. Moreover, 2 factors--psychological capital and subordinate-supervisor guanxi--moderated the curvilinear relationship, such that the curvilinear relationship is more pronounced among those with lower psychological capital or less positive subordinate-supervisor guanxi.PsycINFO Database Record (c) 2015 APA, all rights reserved.
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