249 research outputs found

    Intra- and interspecific polymorphisms ofLeishmania donovani andL. tropica minicircle DNA

    Get PDF
    A pair of degenerate polymerase chain reaction (PCR) primers (LEI-1, TCG GAT CC[C,T] [G,C]TG GGT AGG GGC GT; LEI-2, ACG GAT CC[G,C] [G,C][A,C]C TAT [A,T]TT ACA CC) defining a 0.15-kb segment ofLeishmania minicircle DNA was constructed. These primers amplified not only inter- but also intraspecifically polymorphic sequences. Individual sequences revealed a higher intraspecific than interspecific divergence. It is concluded that individual sequences are of limited relevance for species determination. In contrast, when a data base of 19 different sequences was analyzed in a dendrographic plot, an accurate species differentiation was feasible

    Narrow-band imaging versus white light for the detection of proximal colon serrated lesions: a randomized, controlled trial

    Get PDF
    Background The value of narrow-band imaging (NBI) for detecting serrated lesions is unknown. Objective To assess NBI for the detection of proximal colon serrated lesions. Design Randomized, controlled trial. Setting Two academic hospital outpatient units. Patients Eight hundred outpatients 50 years of age and older with intact colons undergoing routine screening, surveillance, or diagnostic examinations. Interventions Randomization to colon inspection in NBI versus white-light colonoscopy. Main Outcome Measurements The number of serrated lesions (sessile serrated polyps plus hyperplastic polyps) proximal to the sigmoid colon. Results The mean inspection times for the whole colon and proximal colon were the same for the NBI and white-light groups. There were 204 proximal colon lesions in the NBI group and 158 in the white light group (P = .085). Detection of conventional adenomas was comparable in the 2 groups. Limitations Lack of blinding, endoscopic estimation of polyp location. Conclusion NBI may increase the detection of proximal colon serrated lesions, but the result in this trial did not reach significance. Additional study of this issue is warranted. (Clinical trial registration number: NCT01572428.

    Chronic non-specific low back pain - sub-groups or a single mechanism?

    Get PDF
    Copyright 2008 Wand and O'Connell; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Background: Low back pain is a substantial health problem and has subsequently attracted a considerable amount of research. Clinical trials evaluating the efficacy of a variety of interventions for chronic non-specific low back pain indicate limited effectiveness for most commonly applied interventions and approaches. Discussion: Many clinicians challenge the results of clinical trials as they feel that this lack of effectiveness is at odds with their clinical experience of managing patients with back pain. A common explanation for this discrepancy is the perceived heterogeneity of patients with chronic non-specific low back pain. It is felt that the effects of treatment may be diluted by the application of a single intervention to a complex, heterogeneous group with diverse treatment needs. This argument presupposes that current treatment is effective when applied to the correct patient. An alternative perspective is that the clinical trials are correct and current treatments have limited efficacy. Preoccupation with sub-grouping may stifle engagement with this view and it is important that the sub-grouping paradigm is closely examined. This paper argues that there are numerous problems with the sub-grouping approach and that it may not be an important reason for the disappointing results of clinical trials. We propose instead that current treatment may be ineffective because it has been misdirected. Recent evidence that demonstrates changes within the brain in chronic low back pain sufferers raises the possibility that persistent back pain may be a problem of cortical reorganisation and degeneration. This perspective offers interesting insights into the chronic low back pain experience and suggests alternative models of intervention. Summary: The disappointing results of clinical research are commonly explained by the failure of researchers to adequately attend to sub-grouping of the chronic non-specific low back pain population. Alternatively, current approaches may be ineffective and clinicians and researchers may need to radically rethink the nature of the problem and how it should best be managed

    National malaria prevalence in Cambodia: microscopy versus polymerase chain reaction estimates

    Get PDF
    Accurate information regarding malaria prevalence at national level is required to design and assess malaria control/elimination efforts. Although many comparisons of microscopy and polymerase chain reaction (PCR)-based methods have been conducted, there is little published literature covering such comparisons in southeast Asia especially at the national level. Both microscopic examination and PCR detection were performed on blood films and dried blood spots samples collected from 8,067 individuals enrolled in a nationwide, stratified, multistage, cluster sampling malaria prevalence survey conducted in Cambodia in 2007. The overall malaria prevalence and prevalence rates of Plasmodium falciparum, Plasmodium vivax, and Plasmodium malariae infections estimated by microscopy (N = 8,067) were 2.74% (95% confidence interval [CI]: 2.39-3.12%), 1.81% (95% CI: 1.53-2.13%), 1.14% (95% CI: 0.92-1.40%), and 0.01% (95% CI: 0.003-0.07%), respectively. The overall malaria prevalence based on PCR detection (N = 7,718) was almost 2.5-fold higher (6.31%, 95% CI: 5.76-6.89%, P < 0.00001). This difference was significantly more pronounced for P. falciparum (4.40%, 95% CI: 3.95-4.90%, P < 0.00001) compared with P. vivax (1.89%, 95% CI: 1.60-2.22%, P < 0.001) and P. malariae infections (0.22%, 95% CI: 0.13-0.35%, P < 0.0001). The significant proportion of microscopy-negative but PCR-positive individuals (289/7,491, 3.85%) suggest microscopic examination frequently underestimated malaria infections and that active case detection based on microscopy may miss a significant reservoir of infection, especially in low-transmission settings

    The changing form of Antarctic biodiversity

    Get PDF
    Antarctic biodiversity is much more extensive, ecologically diverse and biogeographically structured than previously thought. Understanding of how this diversity is distributed in marine and terrestrial systems, the mechanisms underlying its spatial variation, and the significance of the microbiota is growing rapidly. Broadly recognizable drivers of diversity variation include energy availability and historical refugia. The impacts of local human activities and global environmental change nonetheless pose challenges to the current and future understanding of Antarctic biodiversity. Life in the Antarctic and the Southern Ocean is surprisingly rich, and as much at risk from environmental change as it is elsewher

    Impact of a ring fitted cap on insertion time and adenoma detection: a randomized controlled trial

    Get PDF
    Background and Aims: Devices for flattening colon folds can improve polyp detection at colonoscopy. However, there are few data on the endoscopic ring fitted cap (EndoRings, EndoAid, Caesarea, Israel). We sought to compare adenoma detection with EndoRings with that of standard high-definition colonoscopy. Methods: A single-center randomized controlled trial of 562 patients (284 randomized to EndoRings and 278 to standard colonoscopy) at 2 outpatient endoscopy units in the Indiana University Hospital system. Adenoma detection was the primary outcome measured as adenoma detection rate (ADR) and adenomas per colonoscopy (APC). We also compared sessile serrated polyp detection rate (SSPDR), insertion times, withdrawal times, and ease of passage through the sigmoid colon. Results: EndoRings was superior to standard colonoscopy in terms of APC (1.46 vs 1.06, p=0.025) but there were no statistically significant differences in ADR or SSPDR. Mean withdrawal time (in patients with no polyps) was shorter and insertion time (all patients) was longer in the EndoRings arm by 1.8 minutes and 0.75 minutes, respectively. One provider had significantly higher detection with EndoRings and contributed substantially to the overall results. Conclusions: EndoRings can increase adenoma detection without significant increase in procedure time, but the effect varies between operators. EndoRings slows colonoscope insertion

    Economic impact of infections and antibiotics

    Get PDF
    In this chapter, we review several aspects with respect to the burden of infectious diseases, its impact in morbidity and mortality, and its economic burden. Furthermore, we referenced the actual situation with relation to the use of antimicrobial, the resistance problem and misuse of antibiotic, and the economic impact in the health systems

    Health Centre Surveys as a Potential Tool for Monitoring Malaria Epidemiology by Area and over Time

    Get PDF
    BACKGROUND: Presently, many malaria control programmes use health facility data to evaluate the impact of their interventions. Facility-based malaria data, although useful, have problems with completeness, validity and representativeness and reliance on routinely collected health facility data might undermine demonstration of the magnitude of the impact of the recent scaleups of malaria interventions. To determine whether carefully conducted health centre surveys can be reliable means of monitoring area specific malaria epidemiology, we have compared malaria specific indices obtained from surveys in health centres with indices obtained from cross-sectional surveys conducted in their catchment communities. METHODS: A series of age stratified, seasonal, cross-sectional surveys were conducted during the peak malaria transmission season in 2008 and during the following dry season in 2009 in six ecologically diverse areas in The Gambia. Participants were patients who attended the health centres plus a representative sample from the catchment villages of these health facilities. Parasitaemia, anaemia, attributable proportion of fever and anti-MSP1-(19) antibody seroprevalence were compared in the health facility attendees and community participants. RESULTS: A total of 16,230 subjects completed the study; approximately half participated in the health centre surveys and half in the wet season surveys. Data from both the health centre and community surveys showed that malaria endemicity in The Gambia is now low, heterogeneous and seasonal. In the wet season, parasitaemia, seroprevalence and fever prevalence were higher in subjects seen in the health centres than in the community surveys. Age patterns of parasitaemia, attributable proportions of fever and seroprevalence rates were similar in subjects who participated in the community and health centre surveys. CONCLUSION: Health centre surveys have potential as a surveillance tool for evaluating area specific malaria control activities and for monitoring changes in local malaria epidemiology over time

    Sterile Protection against Plasmodium knowlesi in Rhesus Monkeys from a Malaria Vaccine: Comparison of Heterologous Prime Boost Strategies

    Get PDF
    Using newer vaccine platforms which have been effective against malaria in rodent models, we tested five immunization regimens against Plasmodium knowlesi in rhesus monkeys. All vaccines included the same four P. knowlesi antigens: the pre-erythrocytic antigens CSP, SSP2, and erythrocytic antigens AMA1, MSP1. We used four vaccine platforms for prime or boost vaccinations: plasmids (DNA), alphavirus replicons (VRP), attenuated adenovirus serotype 5 (Ad), or attenuated poxvirus (Pox). These four platforms combined to produce five different prime/boost vaccine regimens: Pox alone, VRP/Pox, VRP/Ad, Ad/Pox, and DNA/Pox. Five rhesus monkeys were immunized with each regimen, and five Control monkeys received a mock vaccination. The time to complete vaccinations was 420 days. All monkeys were challenged twice with 100 P. knowlesi sporozoites given IV. The first challenge was given 12 days after the last vaccination, and the monkeys receiving the DNA/Pox vaccine were the best protected, with 3/5 monkeys sterilely protected and 1/5 monkeys that self-cured its parasitemia. There was no protection in monkeys that received Pox malaria vaccine alone without previous priming. The second sporozoite challenge was given 4 months after the first. All 4 monkeys that were protected in the first challenge developed malaria in the second challenge. DNA, VRP and Ad5 vaccines all primed monkeys for strong immune responses after the Pox boost. We discuss the high level but short duration of protection in this experiment and the possible benefits of the long interval between prime and boost
    corecore