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1.  The effectiveness and cost-effectiveness of telephone triage of patients requesting same day consultations in general practice: study protocol for a cluster randomised controlled trial comparing nurse-led and GP-led management systems (ESTEEM) 
Trials  2013;14:4.
Background
Recent years have seen an increase in primary care workload, especially following the introduction of a new General Medical Services contract in 2004. Telephone triage and telephone consultation with patients seeking health care represent initiatives aimed at improving access to care. Some evidence suggests that such approaches may be feasible but conclusions regarding GP workload, cost, and patients’ experience of care, safety, and health status are equivocal. The ESTEEM trial aims to assess the clinical- and cost-effectiveness of nurse-led computer-supported telephone triage and GP-led telephone triage, compared to usual care, for patients requesting same-day consultations in general practice.
Methods/design
ESTEEM is a pragmatic, multi-centre cluster randomised clinical trial with patients randomised at practice level to usual care, computer decision-supported nurse triage, or GP-led triage. Following triage of 350–550 patients per practice we anticipate estimating and comparing total primary care workload (volume and time), the economic cost to the NHS, and patient experience of care, safety, and health status in the 4-week period following the index same-day consultation request across the three trial conditions.
We will recruit all patients seeking a non-emergency same-day appointment in primary care. Patients aged 12.0–15.9 years and temporary residents will be excluded from the study.
The primary outcome is the number of healthcare contacts taking place in the 4-week period following (and including) the index same-day consultation request. A range of secondary outcomes will be examined including patient flow, primary care NHS resource use, patients’ experience of care, safety, and health status.
The estimated sample size required is 3,751 patients (11,253 total) in each of the three trial conditions, to detect a mean difference of 0.36 consultations per patient in the four week follow-up period between either intervention group and usual care 90% power, 5% alpha, and an estimated intracluster correlation coefficient ICC of 0.05. The primary analysis will be based on the intention-to-treat principle and take the form of a random effects regression analysis taking account of the hierarchical nature of the study design. Statistical models will allow for adjustment for practice level minimisation variables and patient-level baseline covariates shown to differ at baseline.
Trial registration
Current Controlled Trials ISCRTN20687662
doi:10.1186/1745-6215-14-4
PMCID: PMC3574027  PMID: 23286331
Primary care; Telephone triage; Decision support; General practitioner; Nurse; Workload; Satisfaction; Cost-effectiveness; Cluster randomised controlled trial
2.  Psilocybin occasioned mystical-type experiences: Immediate and persisting dose-related effects 
Psychopharmacology  2011;218(4):649-665.
Rationale
This dose-effect study extends previous observations showing that psilocybin can occasion mystical-type experiences having persisting positive effects on attitudes, mood, and behavior.
Objectives
This double-blind study evaluated psilocybin (0, 5, 10, 20, 30 mg/70 kg, p.o.) administered under supportive conditions.
Methods
Participants were 18 adults (17 hallucinogen-naïve). Five 8-hour sessions were conducted individually for each participant at 1-month intervals. Participants were randomized to receive the four active doses in either ascending or descending order (9 participants each). Placebo was scheduled quasi-randomly. During sessions volunteers used eyeshades and were instructed to direct their attention inward. Volunteers completed questionnaires assessing effects immediately after and 1 month after each session, and at 14 months follow-up.
Results
Psilocybin produced acute perceptual and subjective effects including, at 20 and/or 30 mg/70 kg, extreme anxiety/fear (39% of volunteers) and/or mystical-type experience (72% of volunteers). One month after sessions at the two highest doses, volunteers rated the psilocybin experience as having substantial personal and spiritual significance, and attributed to the experience sustained positive changes in attitudes, mood, and behavior, with the ascending dose sequence showing greater positive effects. At 14 months, ratings were undiminished and were consistent with changes rated by community observers. Both the acute and persisting effects of psilocybin were generally a monotonically increasing function of dose, with the lowest dose showing significant effects.
Conclusions
Under supportive conditions, 20 and 30 mg/70 kg psilocybin occasioned mystical-type experiences having persisting positive effects on attitudes, mood and behavior. Implications for therapeutic trials are discussed.
doi:10.1007/s00213-011-2358-5
PMCID: PMC3308357  PMID: 21674151
psilocybin; dose-effects; hallucinogen; entheogen; psychedelic; mystical experience; fear; spiritual; religion; positive psychology; humans
3.  Successful Interruption of Transmission of Onchocerca volvulus in the Escuintla-Guatemala Focus, Guatemala 
Background
Elimination of onchocerciasis (river blindness) through mass administration of ivermectin in the six countries in Latin America where it is endemic is considered feasible due to the relatively small size and geographic isolation of endemic foci. We evaluated whether transmission of onchocerciasis has been interrupted in the endemic focus of Escuintla-Guatemala in Guatemala, based on World Health Organization criteria for the certification of elimination of onchocerciasis.
Methodology/Principal Findings
We conducted evaluations of ocular morbidity and past exposure to Onchocerca volvulus in the human population, while potential vectors (Simulium ochraceum) were captured and tested for O. volvulus DNA; all of the evaluations were carried out in potentially endemic communities (PEC; those with a history of actual or suspected transmission or those currently under semiannual mass treatment with ivermectin) within the focus. The prevalence of microfilariae in the anterior segment of the eye in 329 individuals (≥7 years old, resident in the PEC for at least 5 years) was 0% (one-sided 95% confidence interval [CI] 0–0.9%). The prevalence of antibodies to a recombinant O. volvulus antigen (Ov-16) in 6,432 school children (aged 6 to 12 years old) was 0% (one-sided 95% IC 0–0.05%). Out of a total of 14,099 S. ochraceum tested for O. volvulus DNA, none was positive (95% CI 0–0.01%). The seasonal transmission potential was, therefore, 0 infective stage larvae per person per season.
Conclusions/Significance
Based on these evaluations, transmission of onchocerciasis in the Escuintla-Guatemala focus has been successfully interrupted. Although this is the second onchocerciasis focus in Latin America to have demonstrated interruption of transmission, it is the first focus with a well-documented history of intense transmission to have eliminated O. volvulus.
Author Summary
Brought to the Americas from Africa by the slave trade, onchocerciasis is present in six countries in Latin America. The disease is caused by a round worm and is transmitted to humans by the bite of an infected black fly. Once in a human, the adult worms produce larvae that circulate through the body, causing itching or even blindness. Ivermectin, a drug that kills the larvae, is delivered by public health authorities in countries where the disease is present. If the larvae are killed, then the disease cannot be transmitted to more people. People living in the Escuintla-Guatemala focus, a region in Guatemala where the disease was common, have been taking ivermectin for many years. The Ministry of Health of Guatemala believes that onchocerciasis is no longer being transmitted in the area. To prove that there is no more transmission of the disease, the authors examined the eyes of residents of the area to see if they could find any evidence of the worms. They also conducted analyses of blood in school children to see if they had ever been exposed to the worm, and they caught thousands of black flies and tested them to see if they were infected. These evaluations found no evidence of transmission of the disease in the Escuintla-Guatemala focus. As a result, local public health authorities can stop giving ivermectin and invest their human resources in other important diseases.
doi:10.1371/journal.pntd.0000404
PMCID: PMC2656640  PMID: 19333366
4.  PHASE: a randomised, controlled trial of supervised self-help cognitive behavioural therapy in primary care. 
BACKGROUND: Common mental health problems account for up to 40% of all general practitioner (GP) consultations. Patients have limited access to evidence-based psychological therapies. Cognitive behavioural therapy self-help strategies offer one potential solution. AIM: To determine differences in clinical outcome, patient satisfaction and costs, between a cognitive behavioural-based self-help package facilitated by practice nurses compared to ordinary care by GPs for mild to moderate anxiety and depression. DESIGN OF STUDY: Randomised controlled trial. SETTING: Seventeen primary healthcare teams. METHOD: Patients presenting to their GP with mild to moderate anxiety and/or depression were recruited to the study and randomised to receive either a self-help intervention facilitated by practice nurses or ordinary care. The self-help intervention consisted of up to three appointments: two 1 week apart and a third 3 months later. There were no restrictions on ordinary care. RESULTS: Intention-to-treat analysis showed that patients treated with practice nurse-supported cognitive behavioural therapy self-help attained similar clinical outcomes for similar costs and were more satisfied than patients treated by GPs with ordinary care. On-treatment analysis showed patients receiving the facilitated cognitive behavioural therapy self-help were more likely to be below clinical threshold at 1 month compared to the ordinary care group (odds ratio [OR] = 3.65, 95% confidence interval [CI] = 1.87 to 4.37). This difference was less well marked at 3 months (OR = 1.36, 95% CI = 0.52 to 3.56). CONCLUSION: Facilitated cognitive behavioural self-help may provide a short-term cost-effective clinical benefit for patients with mild to moderate anxiety and depression. This has the potential to help primary care provide a choice of effective psychological as well as pharmacological treatments for mental health problems.
PMCID: PMC1314708  PMID: 14601351
5.  Glomerular vascular cell adhesion molecule-1 expression in renal vasculitis. 
Journal of Clinical Pathology  1996;49(3):238-242.
AIMS: To study the expression of cell adhesion molecules in the renal biopsy specimens of patients with systemic vasculitis and Henoch-Schönlein purpura (HSP); to correlate this with the severity of glomerular inflammation. METHODS: Renal biopsy specimens obtained from eight patients with untreated systemic vasculitis (four with Wegener's granulomatosis and four with microscopic polyarteritis), eight with HSP and nine controls (four with normal histopathology and five with thin glomerular basement membrane disease) were stained using the alkaline phosphatase anti-alkaline phosphatase method with monoclonal antibodies directed against intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and E-selectin. RESULTS: Biopsy specimens of normal kidneys expressed ICAM-1 in glomerular endocapillary cells, Bowman's capsule epithelium, interstitial cells and interstitial vascular endothelium, and VCAM-1 in Bowman's capsule epithelium, proximal tubular epithelium and interstitial vascular endothelium. No staining with antibody directed against E-selectin was seen in any of the biopsy specimens. Biopsy specimens of patients with a vasculitic glomerulonephritis (segmental necrotising glomerulonephritis) expressed VCAM-1 in glomerular endocapillary cells (four of eight patients with systemic vasculitis; two of eight patients with HSP). In patients with a systemic vasculitis glomerular VCAM-1 expression was associated with a more severe renal lesoin (44, 50, 60, and 65% of glomeruli involved) than in those not showing glomerular VCAM-1 expression (3, 3, 11, and 39% of glomeruli involved). CONCLUSION: Expression of VCAM-1 by glomerular endocapillary cells in renal biopsy specimens raises the possibility that recruitment of VLA-4 bearing leucocytes may contribute to glomerular injury in Wegener's granulomatosis and microscopic polyarteritis.
Images
PMCID: PMC500406  PMID: 8675737
7.  Effects of discrimination by sex and race on the early careers of British medical graduates during 1981-7. 
BMJ : British Medical Journal  1990;301(6758):961-964.
OBJECTIVE--To examine the possible effects of discrimination by sex and race on the career patterns of doctors up to six years after qualifying. DESIGN--Postal questionnaire follow up survey. PARTICIPANTS--1572 Doctors who graduated from five British medical schools in 1981, 1983, and 1985, including 587 women and 131 doctors from ethnic minorities. MAIN OUTCOME MEASURES--Reported success rates of applications for training posts. RESULTS--Comparison of the career patterns of women and men yielded no evidence of discrimination against women in competition for posts. In contrast, there were striking differences in career patterns between graduates of native European origin and those of ethnic minority origin. Graduates from ethnic minorities reported lower success rates and more difficulty in obtaining house officer posts, registrar posts, and places in vocational training schemes in general practice. Most of this discrimination seemed to occur at the stage of shortlisting for interview. Graduates from ethnic minorities were more likely than graduates of native European origin to have experienced spells of unemployment while seeking work. They were also more likely to have changed their original choice of career because of difficulty in obtaining suitable training posts or unfavourable career prospects. CONCLUSIONS--Discrimination against ethnic minorities occurs in the competition for training posts among graduates from British medical schools. There was no evidence of discrimination against women graduates. Shortlisting procedures based on objective scoring systems may help to ensure equality of opportunity in future.
PMCID: PMC1664175  PMID: 2249025
8.  Multimeric Stability of Human C-reactive Protein in Archived Specimens 
PLoS ONE  2013;8(3):e58094.
Background
C-reactive protein (CRP) is a marker of inflammation and a risk predictor of cardiovascular disease. Current CRP assays are focused on the quantification of the CRP levels as pentamers. However, CRP can be present as other multimeric forms. There will be a market need to measure the CRP multimeric structure in addition to the levels in human populations. To meet this need, we investigated whether the long-term archived samples could be used instead of freshly collected samples.
Methodology/Principal Findings
The specimens of serum, plasma and tissues were collected from transgenic rats expressing the human CRP. These samples were stored at 4°C, −20°C and −80°C for different periods. Non-denaturing Western blot analysis was used to observe the influence of storage conditions to multimeric structures of human CRP. Our results showed that there was no difference on multimeric structures of human CRP between samples stored at 4°C, −20°C and −80°C, between samples stored at −80°C for twenty-four hours and three months, and between plasma and serum.
Conclusions/Significance
This study implicated that archived samples stored at these conditions in those large longitudinal studies could be used for investigating the multimeric structures of CRP. Our report may speed up these researches and save labors and budget by enabling them to use currently available archived samples rather than freshly collected samples.
doi:10.1371/journal.pone.0058094
PMCID: PMC3597618
9.  Sexual Health Information Networks: What are Urban African American Youth Learning? 
Research in human development  2012;9(1):54-77.
This qualitative study examined sexual health information networks among urban African American youth living in low-income communities. The authors identified sources, message content, and utility of messages about sex and sexual health in a sample of 15–17-year olds (N = 81). Youth received sexual health information from a variety of sources. Messages from parents and sex education had high utility, whereas messages from the Internet and religion had low utility. Four information network patterns were identified, suggesting considerable variation in how youth are socialized regarding sex. Findings suggest that sexual information networks have the potential to affect sexual health and development.
doi:10.1080/15427609.2012.654432
PMCID: PMC3322617  PMID: 22505842
10.  Exploratory Studies in Sensory Reinforcement in Male Rats: Effects of Methamphetamine 
Understanding sensory reinforcement and the effects of stimulant drugs on sensory reinforcers is potentially important for understanding their influence on addiction processes. Experiment 1 explored the reinforcing properties of a visual stimulus and the effects of methamphetamine (METH) on responding maintained by a visual reinforcer (VRF) in male rats. Snout poke responses to the active alternative produced the VRF according to variable interval (VI) schedules of reinforcement, and responses to an inactive alternative had no programmed effect. Experiment 2 explored the effects of METH on choice between the VRF and a water reinforcer (H2ORF) using concurrent VI schedules in male rats. In Experiment 1, response-contingent onset of the VRF produced an increase in both the relative frequency and absolute rate of active responding. The rate of both active and inactive responding declined across the 40-min test sessions. METH did not differentially enhance active responding for the VRF. Instead, METH nondifferentially increased the rate of responding and attenuated the within-session decline of responding. In Experiment 2, METH differentially increased the rate of responding for the VRF relative to the H2ORF. The results of these exploratory experiments indicate that the reinforcing effects of the VRF were weak and transient. In addition, METH treatment increased responding, and the specificity of the enhancement of METH was dependent upon the testing conditions. Potential explanations of these differences, such as novelty and reinforcer type, are discussed.
doi:10.1037/a0025701
PMCID: PMC3591505  PMID: 21942261
novelty; drug abuse; operant conditioning; rats; learning
11.  Space Fortress game training and executive control in older adults: A pilot intervention 
We investigated the feasibility of using the Space Fortress (SF) game, a complex video game originally developed to study complex skill acquisition in young adults, to improve executive control processes in cognitively healthy older adults. The study protocol consisted of 36 one-hour game play sessions over 3 months with cognitive evaluations before and after, and a follow-up evaluation at 6 months. Sixty participants were randomized to one of three conditions: Emphasis Change (EC) – elders were instructed to concentrate on playing the entire game but place particular emphasis on a specific aspect of game play in each particular game; Active Control (AC) – game play with standard instructions; Passive Control (PC) – evaluation sessions without game play. Primary outcome measures were obtained from five tasks, presumably tapping executive control processes. A total of 54 older adults completed the study protocol. One measure of executive control, WAIS-III letter–number sequencing, showed improvement in performance from pre- to post-evaluations in the EC condition, but not in the other two conditions. These initial findings are modest but encouraging. Future SF interventions need to carefully consider increasing the duration and or the intensity of the intervention by providing at-home game training, reducing the motor demands of the game, and selecting appropriate outcome measures.
doi:10.1080/13825585.2011.613450
PMCID: PMC3591462  PMID: 21988726
Aging; Cognition; Intervention; Executive control; Video games
12.  Asparagine Synthetase Chemotherapy 
Annual review of biochemistry  2006;75:629-654.
Modern clinical treatments of childhood acute lymphoblastic leukemia (ALL) employ enzyme-based methods for depletion of blood asparagine in combination with standard chemotherapeutic agents. Significant side effects can arise in these protocols and, in many cases, patients develop drug-resistant forms of the disease that may be correlated with up-regulation of the enzyme glutamine-dependent asparagine synthetase (ASNS). Though the precise molecular mechanisms that result in the appearance of drug resistance are the subject of active study, potent ASNS inhibitors may have clinical utility in treating asparaginase-resistant forms of childhood ALL. This review provides an overview of recent developments in our understanding of (a) the structure and catalytic mechanism of ASNS, and (b) the role that ASNS may play in the onset of drug-resistant childhood ALL. In addition, the first successful, mechanism-based efforts to prepare and characterize nanomolar ASNS inhibitors are discussed, together with the implications of these studies for future efforts to develop useful drugs.
doi:10.1146/annurev.biochem.75.103004.142520
PMCID: PMC3587692  PMID: 16756505
amino acids; asparaginase resistance; drug discovery; enzyme inhibitors; leukemia
13.  The mechanobiology of mitral valve function, degeneration, and repair 
In degenerative valve disease, the highly organized mitral valve leaflet matrix stratification is progressively destroyed and replaced with proteoglycan rich, mechanically inadequate tissue. This is driven by the actions of originally quiescent valve interstitial cells that become active contractile and migratory myofibroblasts. While treatment for myxomatous mitral valve disease in humans ranges from repair to total replacement, therapies in dogs focus on treating the consequences of the resulting mitral regurgitation. The fundamental gap in our understanding is how the resident valve cells respond to altered mechanical signals to drive tissue remodeling. Despite the pathological similarities and high clinical occurrence, surprisingly little mechanistic insight has been gleaned from the dog. This review presents what is known about mitral valve mechanobiology from clinical, in vivo, and in vitro data. There are a number of experimental strategies already available to pursue this significant opportunity, but success requires the collaboration between veterinary clinicians, scientists, and engineers.
doi:10.1016/j.jvc.2012.01.002
PMCID: PMC3586284  PMID: 22366572
Strain; Stress; Myxomatous; Biomechanics; Myofibroblast
14.  Does Litter Size Variation Affect Models of Terrestrial Carnivore Extinction Risk and Management? 
PLoS ONE  2013;8(2):e58060.
Background
Individual variation in both survival and reproduction has the potential to influence extinction risk. Especially for rare or threatened species, reliable population models should adequately incorporate demographic uncertainty. Here, we focus on an important form of demographic stochasticity: variation in litter sizes. We use terrestrial carnivores as an example taxon, as they are frequently threatened or of economic importance. Since data on intraspecific litter size variation are often sparse, it is unclear what probability distribution should be used to describe the pattern of litter size variation for multiparous carnivores.
Methodology/Principal Findings
We used litter size data on 32 terrestrial carnivore species to test the fit of 12 probability distributions. The influence of these distributions on quasi-extinction probabilities and the probability of successful disease control was then examined for three canid species – the island fox Urocyon littoralis, the red fox Vulpes vulpes, and the African wild dog Lycaon pictus. Best fitting probability distributions differed among the carnivores examined. However, the discretised normal distribution provided the best fit for the majority of species, because variation among litter-sizes was often small. Importantly, however, the outcomes of demographic models were generally robust to the distribution used.
Conclusion/Significance
These results provide reassurance for those using demographic modelling for the management of less studied carnivores in which litter size variation is estimated using data from species with similar reproductive attributes.
doi:10.1371/journal.pone.0058060
PMCID: PMC3585178  PMID: 23469140
15.  Clinical and Biological Relevance of Genomic Heterogeneity in Chronic Lymphocytic Leukemia 
PLoS ONE  2013;8(2):e57356.
Background
Chronic lymphocytic leukemia (CLL) is typically regarded as an indolent B-cell malignancy. However, there is wide variability with regards to need for therapy, time to progressive disease, and treatment response. This clinical variability is due, in part, to biological heterogeneity between individual patients’ leukemias. While much has been learned about this biological variation using genomic approaches, it is unclear whether such efforts have sufficiently evaluated biological and clinical heterogeneity in CLL.
Methods
To study the extent of genomic variability in CLL and the biological and clinical attributes of genomic classification in CLL, we evaluated 893 unique CLL samples from fifteen publicly available gene expression profiling datasets. We used unsupervised approaches to divide the data into subgroups, evaluated the biological pathways and genetic aberrations that were associated with the subgroups, and compared prognostic and clinical outcome data between the subgroups.
Results
Using an unsupervised approach, we determined that approximately 600 CLL samples are needed to define the spectrum of diversity in CLL genomic expression. We identified seven genomically-defined CLL subgroups that have distinct biological properties, are associated with specific chromosomal deletions and amplifications, and have marked differences in molecular prognostic markers and clinical outcomes.
Conclusions
Our results indicate that investigations focusing on small numbers of patient samples likely provide a biased outlook on CLL biology. These findings may have important implications in identifying patients who should be treated with specific targeted therapies, which could have efficacy against CLL cells that rely on specific biological pathways.
doi:10.1371/journal.pone.0057356
PMCID: PMC3585365  PMID: 23468975
16.  Mouse Models of Multiple Sclerosis: Experimental Autoimmune Encephalomyelitis and Theiler’s Virus-Induced Demyelinating Disease 
Experimental autoimmune encephalomyelitis (EAE) and Theiler’s Murine Encephalitis Virus-Induced Demyelinating Disease (TMEV-IDD) are two clinically relevant murine models of multiple sclerosis (MS). Like MS, both are characterized by mononuclear cell infiltration into the CNS and demyelination. EAE is induced by either the administration of myelin protein or peptide in adjuvant or by the adoptive transfer of encephalitogenic T cell blasts into naïve recipients. The relative merits of each of these protocols are compared. Depending on the type of question being asked, different mouse strains and peptides are used. Different disease courses are observed with different strains and different peptides in active EAE. These variations are also addressed. Additionally, issues relevant to clinical grading of EAE in mice are discussed. In addition to EAE induction, useful references for other disease indicators such as DTH, in vitro proliferation, and immunohistochemistry are provided. TMEV-IDD is a useful model for understanding the possible viral etiology of MS. This section provides detailed information on the preparation of viral stocks and subsequent intracerebral infection of mice. Additionally, virus plaque assay and clinical disease assessment are discussed. Recently, recombinant TMEV strains have been created for the study of molecular mimicry which incorporate various 30 amino acid myelin epitopes within the leader region of TMEV.
doi:10.1007/978-1-60761-720-4_19
PMCID: PMC3583382  PMID: 22933080
Multiple sclerosis; Experimental autoimmune encephalomyelitis; EAE; Emulsion; Active induction; Adoptive transfer; T cell blasts; Encephalitogenic; Neurodegeneration; Theiler’s murine encephalomyelitis virus-induced demyelinating disease; PLP; MOG; Myelin; MBP; VP2; VP3; Relapsing–remitting; Epitope spreading
17.  Silencing of Human Phosphatidylethanolamine-Binding Protein 4 Enhances Rituximab-Induced Death and Chemosensitization in B-Cell Lymphoma 
PLoS ONE  2013;8(2):e56829.
Rituximab is the first line drug to treat non Hodgkin’s lymphoma (B-NHL) alone or in combination with chemotherapy. However, 30–40% of B-NHL patients are unresponsive to rituximab or resistant after therapy. Human phosphatidylethanolamine-binding protein 4 (hPEBP4) is a novel member of PEBP family and functions as an anti-apoptotic molecule. In this study, we found hPEBP4 to be expressed in up to 90% of B-cell lymphoma patients, but in only 16.7% of normal lymph nodes. Interestingly, hPEBP4 overexpression inhibited rituximab-mediated complement dependent cytotoxicity (R-CDC) and antibody-dependent cell-mediated cytotoxicity (ADCC) in B-NHL cells while downregulation of hPEBP4 augmented the therapeutic efficacy of rituximab both in vitro and in vivo. Furthermore, hPEBP4 silencing sensitized the primary B-acute lymphocytic leukemia (B-ALL) cells to R-CDC. During rituximab-mediated complement dependent cytotoxicity, hPEBP4 was recruited to the cell membrane in a PE-binding domain dependent manner and inhibited R-CDC induced calcium flux and reactive oxygen species (ROS) generation. These events contributed to the decrease of cell death induced by R-CDC in B-cell lymphomas. Meanwhile, hPEBP4 knockdown potentiated the chemosensitization of the rituximab in B-cell lymphoma cells by regulating the expression of Bcl-xl, Cycline E, p21waf/cip1 and p53 and the activation of caspase-3 and caspase-9. Considering that hPEBP4 conferred cellular resistance to rituximab treatment and was preferentially expressed in lymphoma tissue, it could be a potential valuable target for adjuvant therapy for B-cell lymphoma.
doi:10.1371/journal.pone.0056829
PMCID: PMC3581549  PMID: 23451095
18.  Genetic Determinants of Trabecular and Cortical Volumetric Bone Mineral Densities and Bone Microstructure 
PLoS Genetics  2013;9(2):e1003247.
Most previous genetic epidemiology studies within the field of osteoporosis have focused on the genetics of the complex trait areal bone mineral density (aBMD), not being able to differentiate genetic determinants of cortical volumetric BMD (vBMD), trabecular vBMD, and bone microstructural traits. The objective of this study was to separately identify genetic determinants of these bone traits as analysed by peripheral quantitative computed tomography (pQCT). Separate GWA meta-analyses for cortical and trabecular vBMDs were performed. The cortical vBMD GWA meta-analysis (n = 5,878) followed by replication (n = 1,052) identified genetic variants in four separate loci reaching genome-wide significance (RANKL, rs1021188, p = 3.6×10−14; LOC285735, rs271170, p = 2.7×10−12; OPG, rs7839059, p = 1.2×10−10; and ESR1/C6orf97, rs6909279, p = 1.1×10−9). The trabecular vBMD GWA meta-analysis (n = 2,500) followed by replication (n = 1,022) identified one locus reaching genome-wide significance (FMN2/GREM2, rs9287237, p = 1.9×10−9). High-resolution pQCT analyses, giving information about bone microstructure, were available in a subset of the GOOD cohort (n = 729). rs1021188 was significantly associated with cortical porosity while rs9287237 was significantly associated with trabecular bone fraction. The genetic variant in the FMN2/GREM2 locus was associated with fracture risk in the MrOS Sweden cohort (HR per extra T allele 0.75, 95% confidence interval 0.60–0.93) and GREM2 expression in human osteoblasts. In conclusion, five genetic loci associated with trabecular or cortical vBMD were identified. Two of these (FMN2/GREM2 and LOC285735) are novel bone-related loci, while the other three have previously been reported to be associated with aBMD. The genetic variants associated with cortical and trabecular bone parameters differed, underscoring the complexity of the genetics of bone parameters. We propose that a genetic variant in the RANKL locus influences cortical vBMD, at least partly, via effects on cortical porosity, and that a genetic variant in the FMN2/GREM2 locus influences GREM2 expression in osteoblasts and thereby trabecular number and thickness as well as fracture risk.
Author Summary
Osteoporosis is a common highly heritable skeletal disease characterized by reduced bone mineral density (BMD) and deteriorated bone microstructure, resulting in an increased risk of fracture. Most previous genetic epidemiology studies have focused on the genetics of the complex trait BMD, not being able to separate genetic determinants of the trabecular and cortical bone compartments and bone microstructure. The trabecular and cortical BMDs can be analysed separately by computed tomography. Therefore, we performed separate genome-wide association studies for trabecular and cortical BMDs, demonstrating that the genetic determinants of cortical and trabecular BMDs differ. Genetic variants in the RANKL, LOC285735, OPG, and ESR1 loci were associated with cortical BMD, while a genetic variant in the FMN2/GREM2 locus was associated with trabecular BMD. Two of these are novel bone-related loci. Follow-up analyses of bone microstructure demonstrated that a genetic variant in the RANKL locus is associated with cortical porosity and that the FMN2/GREM2 locus is associated with trabecular number and thickness. We propose that a genetic variant in the RANKL locus influences cortical BMD via effects on cortical porosity, and that a genetic variant in the FMN2/GREM2 locus influences trabecular BMD and fracture risk via effects on both trabecular number and thickness.
doi:10.1371/journal.pgen.1003247
PMCID: PMC3578773  PMID: 23437003
19.  Gene profiling reveals a role for stress hormones in the molecular and behavioral response to food restriction 
Biological Psychiatry  2012;71(4):358-365.
Background
Food restriction is known to enhance learning and motivation. The neural mechanisms underlying these responses likely involve alterations in gene expression in brain regions mediating the motivation to feed.
Methods
Analysis of gene expression profiles in male C57BL6/J mice using whole-genome microarrays was completed in the medial prefrontal cortex, nucleus accumbens, ventral tegmental area, and the hypothalamus following a five day food restriction. Quantitative PCR was used to validate these findings and determine the time-course of expression changes. Plasma levels of the stress hormone corticosterone (CORT) were measured by ELISA. Expression changes were measured in adrenalectomized animals that underwent food restriction, as well as in animals receiving daily injections of CORT. Progressive ratio responding for food, a measure of motivated behavior, was assessed after CORT treatment in restricted and fed animals.
Results
Brief food restriction results in an upregulation of peripheral stress responsive genes in the mammalian brain. Time-course analysis demonstrated rapid and persistent expression changes in all four brain regions under study. Administration of CORT to non-restricted animals was sufficient to induce a subset of the genes, and alterations in gene expression after food restriction were dependent on intact adrenal glands. CORT can increase the motivation to work for food only in the restricted state.
Conclusions
These data demonstrate a central role for CORT in mediating both molecular and behavioral responses to food restriction. The stress hormone-induced alterations in gene expression described here may be relevant for both adaptive and pathological responses to stress.
doi:10.1016/j.biopsych.2011.06.028
PMCID: PMC3237832  PMID: 21855858
transcription; neural plasticity; starvation; obesity; motivation; stress hormones
20.  Genetic Modification of the Association of Paraquat and Parkinson’s Disease 
Paraquat is one of the most widely used herbicides worldwide. It produces a Parkinson’s disease (PD) model in rodents through redox cycling and oxidative stress (OS) and is associated with PD risk in humans. Glutathione transferases provide cellular protection against OS and could potentially modulate paraquat toxicity. We investigated PD risk associated with paraquat use in individuals with homozygous deletions of the genes encoding glutathione S-transferase M1 (GSTM1) or T1 (GSTT1). Eighty-seven PD subjects and 343 matched controls were recruited from the Agricultural Health Study, a study of licensed pesticide applicators and spouses in Iowa and North Carolina. PD was confirmed by in-person examination. Paraquat use and covariates were determined by interview. We genotyped subjects for homozygous deletions of GSTM1 (GSTM1*0) and GSTT1 (GSTT1*0) and tested interaction between paraquat use and genotype using logistic regression. Two hundred and twenty-three (52%) subjects had GSTM1*0, 95 (22%) had GSTT1*0, and 73 (17%; all men) used paraquat. After adjustment for potential confounders, there was no interaction with GSTM1. In contrast, GSTT1 genotype significantly modified the association between paraquat and PD. In men with functional GSTT1, the odds ratio (OR) for association of PD with paraquat use was 1.5 (95% confidence interval [CI]: 0.6–3.6); in men with GSTT1*0, the OR was 11.1 (95% CI: 3.0–44.6; P interaction: 0.027). Although replication is needed, our results suggest that PD risk from paraquat exposure might be particularly high in individuals lacking GSTT1. GSTT1*0 is common and could potentially identify a large subpopulation at high risk of PD from oxidative stressors such as paraquat.
doi:10.1002/mds.25216
PMCID: PMC3572192  PMID: 23045187
Parkinson’s disease; paraquat; glutathione transferase; pesticide; gene-environment interaction
21.  Sialoadhesin Ligand Expression Identifies a Subset of CD4+Foxp3− T Cells with a Distinct Activation and Glycosylation Profile 
Sialoadhesin (Sn) is a sialic acid–binding Ig-like lectin expressed selectively on macrophage subsets. In a model of experimental autoimmune encephalomyelitis, Sn interacted with sialylated ligands expressed selectively on CD4+Foxp3+ regulatory T cells (Tregs) and inhibited their proliferation. In this study, we examined the induction of Sn ligands (SnL) on all splenic CD4+ T cells following in vitro activation. Most CD4+ Tregs strongly upregulated SnL, whereas only a small subset of ∼20% CD4+Foxp3− T cells (effector T cells [Teffs]) upregulated SnL. SnL+ Teffs displayed higher levels of activation markers CD25 and CD69, exhibited increased proliferation, and produced higher amounts of IL-2 and IFN-γ than corresponding SnL− Teffs. Coculture of activated Teffs with Sn+ macrophages or Sn+ Chinese hamster ovary cells resulted in increased cell death, suggesting a regulatory role for Sn–SnL interactions. The key importance of α2,3-sialylation in SnL expression was demonstrated by increased binding of α2,3-linkage–specific Maackia amurensis lectin, increased expression of α2,3-sialyltransferase ST3GalVI, and loss of SnL following treatment with an α2,3-linkage–specific sialidase. The induction of SnL on activated CD4+ T cells was dependent on N-glycan rather than O-glycan biosynthesis and independent of the mucin-like molecules CD43 and P-selectin glycoprotein ligand-1, previously implicated in Sn interactions. Induction of ligands on CD4+Foxp3− Teffs was also observed in vivo using the New Zealand Black × New Zealand White F1 murine model of spontaneous lupus and SnL levels on Teffs correlated strongly with the degree of proteinuria. Collectively, these data indicate that SnL is a novel marker of activated CD4+ Teffs that are implicated in the pathogenesis of autoimmune diseases.
doi:10.4049/jimmunol.1201172
PMCID: PMC3586974  PMID: 23408841
22.  A Microarray Platform-Independent Classification Tool for Cell of Origin Class Allows Comparative Analysis of Gene Expression in Diffuse Large B-cell Lymphoma 
PLoS ONE  2013;8(2):e55895.
Cell of origin classification of diffuse large B-cell lymphoma (DLBCL) identifies subsets with biological and clinical significance. Despite the established nature of the classification existing studies display variability in classifier implementation, and a comparative analysis across multiple data sets is lacking. Here we describe the validation of a cell of origin classifier for DLBCL, based on balanced voting between 4 machine-learning tools: the DLBCL automatic classifier (DAC). This shows superior survival separation for assigned Activated B-cell (ABC) and Germinal Center B-cell (GCB) DLBCL classes relative to a range of other classifiers. DAC is effective on data derived from multiple microarray platforms and formalin fixed paraffin embedded samples and is parsimonious, using 20 classifier genes. We use DAC to perform a comparative analysis of gene expression in 10 data sets (2030 cases). We generate ranked meta-profiles of genes showing consistent class-association using ≥6 data sets as a cut-off: ABC (414 genes) and GCB (415 genes). The transcription factor ZBTB32 emerges as the most consistent and differentially expressed gene in ABC-DLBCL while other transcription factors such as ARID3A, BATF, and TCF4 are also amongst the 24 genes associated with this class in all datasets. Analysis of enrichment of 12323 gene signatures against meta-profiles and all data sets individually confirms consistent associations with signatures of molecular pathways, chromosomal cytobands, and transcription factor binding sites. We provide DAC as an open access Windows application, and the accompanying meta-analyses as a resource.
doi:10.1371/journal.pone.0055895
PMCID: PMC3570548  PMID: 23424639
23.  Double-blind, placebo-controlled, two-period, crossover trial to examine the pharmacokinetics of lisdexamfetamine dimesylate in healthy older adults 
Background
Pharmacokinetic and safety data on stimulants in older adults are limited. The objective of this study was to characterize the pharmacokinetics of lisdexamfetamine dimesylate (LDX), a d-amphetamine prodrug, in older adults.
Methods
In this two-period crossover trial, healthy adults (n = 47) stratified by age (55–64, 65–74, and ≥ 75 years) and gender received randomized, double-blind, single doses of LDX 50 mg or placebo. Baseline creatinine clearance, d-amphetamine and intact LDX pharmacokinetics, and safety were assessed.
Results
Mean (±standard deviation) baseline creatinine clearance in participants aged 55–64, 65–74, and ≥ 75 years was 102.5 ± 26.1, 105.3 ± 23.1, and 94.9 ± 27.3 mL per minute, respectively. In the groups aged 55–64, 65–74, and ≥ 75 years, the mean maximum plasma d-amphetamine concentration in men was 44.2 ± 11.1, 47.7 ± 7.0, and 53.4 ± 19.4 ng/mL, respectively; area under the concentration time curve from time 0 extrapolated to infinity (AUC0–inf) was 915.0 ± 164.9, 1123.0 ± 227.0, and 1325.0 ± 464.4 nghour/mL; median time to reach peak plasma concentration was 4.5, 3.5, and 5.5 hours; in women, mean maximum plasma d-amphetamine concentration was 51.0 ± 6.7, 50.2 ± 6.8, and 64.3 ± 12.1 ng/mL, AUC0–inf was 1034.5 ± 154.6, 988.4 ± 80.5, and 1347.8 ± 198.9 ng hour/mL, and median time to reach peak plasma concentration was 3.5, 4.1, and 5.5 hours, respectively. d-Amphetamine clearance was unrelated to baseline creatinine clearance. Five participants aged 55–64 years reported treatment-emergent adverse events (versus one each aged 65–74 and ≥ 75 years), and as did six women (versus one man). No trends in blood pressure or pulse changes were seen with LDX according to age. In participants aged 55–64, 65–74, and ≥ 75 years, the mean change from time-matched baseline pulse ranged from –5.0 to 14.7, –4.3 to 9.5, and –3.0 to 14.7 beats per minute; for systolic blood pressure, from –3.9 to 18.5 mmHg, –2.1 to 14.5 mmHg, and –5.9 to 16.0 mmHg; for diastolic blood pressure from –2.5 to 8.3 mmHg, from –0.8 to 9.4 mmHg, and –0.6 to 9.5 mmHg. Vital sign changes were similar between men and women.
Conclusion
Clearance of d-amphetamine decreased with age and was unrelated to creatinine clearance. No trends in pulse or blood pressure changes with LDX were seen according to age. The safety profile of LDX was consistent with prior observations in younger adult study participants.
doi:10.2147/NDT.S38377
PMCID: PMC3575217  PMID: 23431065
lisdexamfetamine dimesylate; older adults; pharmacokinetics; attention-deficit; hyperactivity disorder; d-amphetamine
24.  A proposal for reducing the effect of one of many causes of publication bias 
Trials  2013;14:41.
In order to avoid publication bias, all trials should be registered at initiation and their results made easily accessible. However, some trial results are more difficult to publish than others. This report describes one such trial and highlights the need for a way of making results of trials widely available even if not presented in the traditional format. Until such time as it is required by law both to register all trials and enter their final results into the database, a lack of resources will mean that some trial results are never published. The scale of the problem of non-publication is unknown and for valid trial results any form of publication is better than none. Therefore it is essential that a quick and easy way is available to act as a safety net to catch trial results that would otherwise be lost.
doi:10.1186/1745-6215-14-41
PMCID: PMC3598957  PMID: 23402474
Publication bias; Randomized trial; Polycythaemia; Busulphan; Radioactive phosphorous; Venesection
25.  Knock-Down of PRAME Increases Retinoic Acid Signaling and Cytotoxic Drug Sensitivity of Hodgkin Lymphoma Cells 
PLoS ONE  2013;8(2):e55897.
The prognosis for patients with Hodgkin lymphoma (HL) has improved in recent decades. On the other hand, not all patients can be cured with the currently established therapy regimes and this therapy is associated with several adverse late effects. Therefore it is necessary to develop new therapy strategies. After treatment of L-540 HL cells with 5′-azacytidine (5AC), we observed increased expression of the preferentially expressed antigen in melanoma (PRAME). In addition, we detected an increased resistance of 5AC-treated cells against cytotoxic drugs. We analyzed the influence of PRAME on cell survival of HL cells by knocking down PRAME in the chemotherapy resistant cell line L-428, a cell line that express PRAME at a high level. After knock-down of PRAME using vector based RNA interference we observed increased sensitivity for cisplatin, etoposide and retinoic acid. DNA microarray analysis of HL cells after PRAME knock-down indicated regulation of several genes including down-regulation of known anti-apoptotic factors. Increased retinoic acid signaling in these cells was revealed by increased expression of the retinoic acid metabolizing cytochrome P450 (CYP26B1), a transcriptional target of retinoic acid signaling. Our data suggest that PRAME inhibits retinoic acid signaling in HL cells and that the knock-down of PRAME might be an interesting option for the development of new therapy strategies for patients with chemo-resistant HL.
doi:10.1371/journal.pone.0055897
PMCID: PMC3569423  PMID: 23409080

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