685 research outputs found

    Intrarectal quinine for treating Plasmodium falciparum malaria: a systematic review

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    BACKGROUND: In children with malaria caused by Plasmodium falciparum, quinine administered rectally may be easier to use and less painful than intramuscular or intravenous administration. The objective of this review was to compare the effectiveness of intrarectal with intravenous or intramuscular quinine for treating falciparum malaria. METHODS: All randomized and quasi-randomized controlled trials comparing intrarectal with intramuscular or intravenous quinine for treating people with falciparum malaria located through the following sources were included: Cochrane Infectious Diseases Group Specialized Register, CENTRAL, MEDLINE, EMBASE, LILACS and CINAHL. Trial quality was assessed and data, including adverse event data, were extracted. Dichotomous data were analysed using odds ratios and continuous data using weighted mean difference. RESULTS: Eight randomized controlled trials (1,247 children) fulfilled the inclusion criteria. The same principal investigator led seven of the trials. Five compared intrarectal with intravenous quinine, and six compared intrarectal with intramuscular treatment. No statistically significant difference was detected for death, parasite clearance by 48 hours and seven days, parasite and fever clearance time, coma recovery time, duration of hospitalization and time before drinking began. One trial (898 children) reported that intrarectal was less painful than intramuscular administration. CONCLUSION: No difference in the effect on parasites and clinical illness was detected for the use of intrarectal quinine compared with other routes, but most trials were small. Pain during application may be less with intrarectal quinine. Further larger trials, in patients with severe malaria and in adults, are required before the intrarectal route could be recommended

    Precision Pointing Control System (PPCS) system design and analysis

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    The precision pointing control system (PPCS) is an integrated system for precision attitude determination and orientation of gimbaled experiment platforms. The PPCS concept configures the system to perform orientation of up to six independent gimbaled experiment platforms to design goal accuracy of 0.001 degrees, and to operate in conjunction with a three-axis stabilized earth-oriented spacecraft in orbits ranging from low altitude (200-2500 n.m., sun synchronous) to 24 hour geosynchronous, with a design goal life of 3 to 5 years. The system comprises two complementary functions: (1) attitude determination where the attitude of a defined set of body-fixed reference axes is determined relative to a known set of reference axes fixed in inertial space; and (2) pointing control where gimbal orientation is controlled, open-loop (without use of payload error/feedback) with respect to a defined set of body-fixed reference axes to produce pointing to a desired target

    A new approach for the limit to tree height using a liquid nanolayer model

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    Liquids in contact with solids are submitted to intermolecular forces inferring density gradients at the walls. The van der Waals forces make liquid heterogeneous, the stress tensor is not any more spherical as in homogeneous bulks and it is possible to obtain stable thin liquid films wetting vertical walls up to altitudes that incompressible fluid models are not forecasting. Application to micro tubes of xylem enables to understand why the ascent of sap is possible for very high trees like sequoias or giant eucalyptus.Comment: In the conclusion is a complementary comment to the Continuum Mechanics and Thermodynamics paper. 21 pages, 4 figures. Continuum Mechanics and Thermodynamics 20, 5 (2008) to appea

    Height and timing of growth spurt during puberty in young people living with vertically acquired HIV in Europe and Thailand.

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    OBJECTIVE: The aim of this study was to describe growth during puberty in young people with vertically acquired HIV. DESIGN: Pooled data from 12 paediatric HIV cohorts in Europe and Thailand. METHODS: One thousand and ninety-four children initiating a nonnucleoside reverse transcriptase inhibitor or boosted protease inhibitor based regimen aged 1-10 years were included. Super Imposition by Translation And Rotation (SITAR) models described growth from age 8 years using three parameters (average height, timing and shape of the growth spurt), dependent on age and height-for-age z-score (HAZ) (WHO references) at antiretroviral therapy (ART) initiation. Multivariate regression explored characteristics associated with these three parameters. RESULTS: At ART initiation, median age and HAZ was 6.4 [interquartile range (IQR): 2.8, 9.0] years and -1.2 (IQR: -2.3 to -0.2), respectively. Median follow-up was 9.1 (IQR: 6.9, 11.4) years. In girls, older age and lower HAZ at ART initiation were independently associated with a growth spurt which occurred 0.41 (95% confidence interval 0.20-0.62) years later in children starting ART age 6 to 10 years compared with 1 to 2 years and 1.50 (1.21-1.78) years later in those starting with HAZ less than -3 compared with HAZ at least -1. Later growth spurts in girls resulted in continued height growth into later adolescence. In boys starting ART with HAZ less than -1, growth spurts were later in children starting ART in the oldest age group, but for HAZ at least -1, there was no association with age. Girls and boys who initiated ART with HAZ at least -1 maintained a similar height to the WHO reference mean. CONCLUSION: Stunting at ART initiation was associated with later growth spurts in girls. Children with HAZ at least -1 at ART initiation grew in height at the level expected in HIV negative children of a comparable age

    Clinico-epidemiological profile and diagnostic procedures of pediatric tuberculosis in a tertiary care hospital of western Nepal-a case-series analysis

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    <p>Abstract</p> <p>Background</p> <p>Changing epidemiology and diagnostic difficulties of paediatric tuberculosis (TB) are being increasingly reported. Our aim was to describe clinico-epidemiological profile and diagnostic procedures used for paediatric TB.</p> <p>Methods</p> <p>A retrospective case-series analysis was carried out in a tertiary care teaching hospital of western Nepal. All pediatric TB (age 0-14 years) patients registered in DOTS clinic during the time period from March, 2003 to July, 2008 were included. Medical case files were reviewed for information on demography, clinical findings, investigations and final diagnosis. Analysis was done on SPSS package. Results were expressed as rates and proportions. Chi square test was used to test for statistical significance.</p> <p>Results</p> <p>About 17.2% (162/941) of TB patients were children. Common symptoms were cough, fever and lymph node swelling. The types of TB were <b/>pulmonary TB (46.3%, 75/162), followed by extra-pulmonary TB (41.4%, 67/162). Twelve patients (7.4%) had disseminated TB. Distribution of types of TB according to gender was similar. PTB was common in younger age than EPTB which was statistically significant. EPTB was mainly localized to lymph node (38, 50.7%), and abdomen (9, 12%). Five main investigations namely Mantoux test, BCG test, chest radiograph, erythrocyte sedimentation rate (ESR) and fine needle aspiration cytology (FNAC) or biopsy were carried out to diagnose TB.</p> <p>Conclusions</p> <p>Paediatric TB in both pulmonary and extrapulmonary forms is a common occurrence in our setting. Age incidence according to type of TB was significant. Diagnosis was based on a combination of epidemiological and clinical suspicion supported by results of various investigations.</p

    The Influence of pCO2 and Temperature on Gene Expression of Carbon and Nitrogen Pathways in Trichodesmium IMS101

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    Growth, protein amount, and activity levels of metabolic pathways in Trichodesmium are influenced by environmental changes such as elevated pCO2 and temperature. This study examines changes in the expression of essential metabolic genes in Trichodesmium grown under a matrix of pCO2 (400 and 900 µatm) and temperature (25 and 31°C). Using RT-qPCR, we studied 21 genes related to four metabolic functional groups: CO2 concentrating mechanism (bicA1, bicA2, ccmM, ccmK2, ccmK3, ndhF4, ndhD4, ndhL, chpX), energy metabolism (atpB, sod, prx, glcD), nitrogen metabolism (glnA, hetR, nifH), and inorganic carbon fixation and photosynthesis (rbcL, rca, psaB, psaC, psbA). nifH and most photosynthetic genes exhibited relatively high abundance and their expression was influenced by both environmental parameters. A two to three orders of magnitude increase was observed for glnA and hetR only when both pCO2 and temperature were elevated. CO2 concentrating mechanism genes were not affected by pCO2 and temperature and their expression levels were markedly lower than that of the nitrogen metabolism and photosynthetic genes. Many of the CO2 concentrating mechanism genes were co-expressed throughout the day. Our results demonstrate that in Trichodesmium, CO2 concentrating mechanism genes are constitutively expressed. Co-expression of genes from different functional groups were frequently observed during the first half of the photoperiod when oxygenic photosynthesis and N2 fixation take place, pointing at the tight and complex regulation of gene expression in Trichodesmium. Here we provide new data linking environmental changes of pCO2 and temperature to gene expression in Trichodesmium. Although gene expression indicates an active metabolic pathway, there is often an uncoupling between transcription and enzyme activity, such that transcript level cannot usually be directly extrapolated to metabolic activity

    Infection control, genetic assessment of drug resistance and drug susceptibility testing in the current management of multidrug/extensively-resistant tuberculosis (M/XDR-TB) in Europe: A tuberculosis network European Trialsgroup (TBNET) study

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    Aim Europe has the highest documented caseload and greatest increase in multidrug and extensively drug-resistant tuberculosis (M/XDR-TB) of all World Health Organization (WHO) regions. This survey examines how recommendations for M/XDR-TB management are being implemented. Methods TBNET is a pan-European clinical research collaboration for tuberculosis. An email survey of TBNET members collected data in relation to infection control, access to molecular tests and basic microbiology with drug sensitivity testing. Results 68/105 responses gave valid information and were from countries within the WHO European Region. Inpatient beds matched demand, but single rooms with negative pressure were only available in low incidence countries; ultraviolet decontamination was used in 5 sites, all with &gt;10 patients with M/XDR-TB per year. Molecular tests for mutations associated with rifampicin resistance were widely available (88%), even in lower income and especially in high incidence countries. Molecular tests for other first line and second line drugs were less accessible (76 and 52% respectively). A third of physicians considered that drug susceptibility results were delayed by &gt; 2 months. Conclusion Infection control for inpatients with M/XDR-TB remains a problem in high incidence countries. Rifampicin resistance is readily detected, but tests to plan regimens tailored to the drug susceptibilities of the strain of Mycobacterium tuberculosis are significantly delayed, allowing for further drug resistance to develop

    An Evaluation of the Fe-N Phase Diagram Considering Long-Range Order of N Atoms in γ'-Fe4N1-x and ε-Fe2N1-z

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    The chemical potential of nitrogen was described as a function of nitrogen content for the Fe-N phases α-Fe[N], γ'-Fe4N1-x, and ε-Fe2N1-z. For α-Fe[N], an ideal, random distribution of the nitrogen atoms over the octahedral interstices of the bcc iron lattice was assumed; for γ'-Fe4N1-x and ε-Fe2N1-z, the occurrence of a long-range ordered distribution of the nitrogen atoms over the octahedral interstices of the close packed iron sublattices (fcc and hcp, respectively) was taken into account. The theoretical expressions were fitted to nitrogen-absorption isotherm data for the three Fe-N phases. The α/α + γ', α + γ'/γ', γ'/γ' + ε, and γ' + ε/ε phase boundaries in the Fe-N phase diagram were calculated from combining the quantitative descriptions for the absorption isotherms with the known composition of NH3/H2 gas mixtures in equilibrium with coexisting α and γ' phases and in equilibrium with coexisting γ' and ε phases. Comparison of the present phase boundaries with experimental data and previously calculated phase boundaries showed a major improvement as compared to the previously calculated Fe-N phase diagrams, where long-range order for the nitrogen atoms in the γ' and ε phases was not accounted for

    Engineering the fatty acid synthesis pathway in Synechococcus elongatus PCC 7942 improves omega-3 fatty acid production

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    Background: The microbial production of fatty acids has received great attention in the last few years as feedstock for the production of renewable energy. The main advantage of using cyanobacteria over other organisms is their ability to capture energy from sunlight and to transform CO2 into products of interest by photosynthesis, such as fatty acids. Fatty acid synthesis is a ubiquitous and well-characterized pathway in most bacteria. However, the activity of the enzymes involved in this pathway in cyanobacteria remains poorly explored. Results: To characterize the function of some enzymes involved in the saturated fatty acid synthesis in cyanobacteria, we genetically engineered Synechococcus elongatus PCC 7942 by overexpressing or deleting genes encoding enzymes of the fatty acid synthase system and tested the lipid profile of the mutants. These modifications were in turn used to improve alpha-linolenic acid production in this cyanobacterium. The mutant resulting from fabF overexpression and fadD deletion, combined with the overexpression of desA and desB desaturase genes from Synechococcus sp. PCC 7002, produced the highest levels of this omega-3 fatty acid. Conclusions: The fatty acid composition of S. elongatus PCC 7942 can be significantly modified by genetically engineering the expression of genes coding for the enzymes involved in the first reactions of fatty acid synthesis pathway. Variations in fatty acid composition of S. elongatus PCC 7942 mutants did not follow the pattern observed in Escherichia coli derivatives. Some of these modifications can be used to improve omega-3 fatty acid production. This work provides new insights into the saturated fatty acid synthesis pathway and new strategies that might be used to manipulate the fatty acid content of cyanobacteria.Work in the FDLC laboratory was financed by the Spanish Ministry of Economy and Competitivity (MINECO) Grant BFU2014-55534-C2-1-P. MSM. was recipientof a Ph.D. fellowship (BES-2012-057387) from MINECO
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