24 research outputs found

    DENSITIES OF DISTRIBUTIONS OF SOLUTIONS TO DELAY STOCHASTIC DIFFERENTIAL EQUATIONS WITH DISCONTINUOUS INITIAL DATA ( PART II)

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    In the present work we have gone a step forward towards integration by part of higher order Malliavin derivatives by formulating and extending some formulas and results on Malliavin calculus and ordinary stochastic differential equations to include delay stochastic differential equations as well as ordinary SDE’s. Here we have also stated clearly what we mean by the Malliavin derivatives and densities of distributions of the solutions process for delay stochastic differential equations which we are considering

    Responses of Periwinkle (Catharanthus roseus) to soil and foliar applications of Haza (Haplophyllum tuberculatum).

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    This study aimed to investigate the responses of Periwinkle plants to soil and foliar applications of Haza plant in two separate tests under the conditions of the nursery at Shambat, Khartoum North, Sudan. The foliar treatments were for boiled water extracts of hand crushed Haza shoots in concentrations: 0.0, 5, 10, 15 and 20 g/l, while the soil dressing test was for powder of dry shoots of Haza applied in doses of: 0.0, 5, 10, 15 and 20 g per plant. The Periwinkle transplants were planted in 18 inch plastic pots containing River Nile sedimentary soil. The study was arranged in complete randomized design and each treatment was replicated 7 times. Data were collected 4 months after applications. The results showed substantial increments in vegetative and reproductive growth parameters coupled with high alkaloids content from soil dressing with 10 g/plant Haza treatment or the foliar application of the 10 g/l Haza extract. These findings elucidated the bio-stimulating potential of Haza applications for enhanced vegetative and reproductive growth beside alkaloids content of Periwinkle. This stimulating potential may be of value for trials on organic production of other horticultural crops

    Enhancing predicted fluoride varnish efficacy and post-treatment compliance by means of calcium-containing gummy bears

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    Objectives This study determined whether consumption of calcium-containing gummies prior to fluoride varnish application enhances plaque fluoride retention and compliance with post-varnish application instructions. Methods The present study followed a multi-center, parallel, randomized, and laboratory analyst-blind design. Following IRB approval, parent consent and child assent, 44 subjects (7–12 years), were randomized to either gummy or no-gummy study groups. A baseline plaque sample was obtained after a wash-out period. Fluoride varnish (5% NaF) was applied; subjects in the gummy group received two calcium-containing gummies prior to varnish application. Subjects were given two questionnaires to complete (subject and parent) to investigate adherence to post-treatment instructions. Three days later, a second plaque sample was obtained. Plaque was analyzed for plaque fluid and solid fluoride concentrations. Fluoride data were analyzed using Wilcoxon Rank Sum tests, questionnaire data using Pearson chi-square tests. Results Plaque fluid fluoride did not change pre- to post-treatment in the gummy group (mean ± sd: 8.8 ± 5.7 μmol/l vs. 10.0 ± 6.3 μmol/l; p = 0.265) or in the no-gummy group (8.1 ± 4.4 μmol/l vs. 16.1 ± 20.0 μmol/l; p = 0.058). Groups were not different for plaque fluid fluoride pre-treatment (p = 1.000), post-treatment (p = 0.904), or change (p = 0.904). Plaque solid fluoride did not change pre- to post-treatment in the gummy group (0.89 ± 1.10 μmol/g vs. 1.37 ± 1.77 μmol/g; p = 0.073) or in the no-gummy group (0.68 ± 0.77 μmol/g vs. 2.01 ± 5.00 μmol/g; p = 0.190). Groups were not different for plaque solid fluoride pre-treatment (p = 1.000), post-treatment (p = 0.466), or change (p = 0.874). No significant differences were found between groups for questionnaire responses. Conclusion This study failed to demonstrate an effect of calcium-containing gummies in enhancing plaque fluoride retention

    Outbreak of Peritonitis in a Continuous Ambulatory Peritoneal Dialysis Population Following the Use of Contaminated Peritoneal Dialysis Fluids

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    Introduction: Most cases of peritonitis during continuous ambulatory peritoneal dialysis (CAPD) are attributed to breaches of the aseptic technique. In this report, we describe an outbreak of CAPD related peritonitis that followed the use of potentially contaminated PD fluid. Outbreak report: CAPD was introduced in the adult nephrology unit at Soba University Hospital in December 2008 with fairly satisfactory functioning and results. In June 2009, we obtained a new supply of PD fluids and started using it. Soon afterwards, a mould was found inside a new unused dialysate bag. During the following days, six patients were diagnosed to have PD related peritonitis. All patients in the unit were immediately shifted to another brand of PD fluids. Enquiry revealed that this supply of PD fluid was stored in a warm and humid environment. We surveyed the 1469 bags in the hospital stock and found another three bags (0.2%) that contained visible mould by the naked eye. The four contaminated bags contained 2.5% dextrose and were from different batches. All of them had lost the negative vacuum between the inner bag and the outer plastic envelope, but had no obvious tears in the envelope and no obvious fluid leakage. Our peritonitis rate before the outbreak was one episode in 21.7 patient-months. This sharply rose to one episode in 2.5 patient-months during the month of the outbreak, and dropped down to one episode in 17.8 patient-months in the 6-months following the outbreak. Conclusion: Contamination of PD fluids can occur during handling and storage. Patients should meticulously examine each bag before usage. Any bag that has lost the vacuum between the inner bag and its outer envelope is potentially breached and should not be used. Keywords: Contamination; Fungal peritonitis; Outbreak; Penicillium spp.; Peritoneal dialysi

    Sero-molecular Epidemiology of Hepatitis E Virus in Blood Donors, Gezira State, Sudan: A Cross-sectional Study

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    Background: Hepatitis E virus (HEV) is a hepatotropic pathogen that causes significant morbidity and mortality in humans. It is an important causative agent of viral hepatitis outbreaks. This study investigates the serological and molecular prevalence of HEV in blood donors attending the Central Blood Bank in Wad Medani City in Gezira State, Sudan. Methods: The study adopted a cross-sectional descriptive design. A structured questionnaire was used to collect data concerning demographic information and risk factors associated with HEV transmission. All enrolled participants (N = 300) were screened for HEV IgG antibodies using commercial ELISA kits, then strong positive samples (N = 84) were selected and rescreened for HEV IgM and HEV RNA by RT PCR. SPSS version 24.0 was used for analysis. Results: Out of 300 male participants, 36.3% (109/300) were positive for HEV IgG. However, only one participant was IgM positive, while the HEV RNA was negative. The highest prevalence rates of the virus were 42 (44.6%) among the age group of 31–40 years, 20 (48.8%) in those who consumed food from outside, 13 (50%) in three to four multiple blood donations, and 5 (62.5%) in those who consumed water from the river source. A significant association of HEV IgG prevalence concerning the occupation of the participants being students or farmers was detected using univariate and multivariate analysis (P-value = 0.007). Conclusion: High prevalence of HEV IgG was demonstrated among the healthy blood donors in this study. Given the possibility of HEV transmission by transfusion from donors to recipients, we recommend that routine screening for HEV should be adopted by blood banks in Sudan

    High frequency of Plasmodium falciparum chloroquine resistance marker (pfcrt T76 mutation) in Yemen: An urgent need to re-examine malaria drug policy

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    <p>Abstract</p> <p>Background</p> <p>Malaria remains a significant health problem in Yemen with <it>Plasmodium falciparum </it>being the predominant species which is responsible for 90% of the malaria cases. Despite serious concerns regarding increasing drug resistance, chloroquine is still used for the prevention and treatment of malaria in Yemen. This study was carried out to determine the prevalence of choloroquine resistance (CQR) of <it>P. falciparum </it>isolated from Yemen based on the <it>pfcrt </it>T76 mutation.</p> <p>Methods</p> <p>A cross-sectional study was carried out among 511 participants from four governorates in Yemen. Blood samples were screened using microscopic and species-specific nested PCR based on the 18S rRNA gene to detect and identify <it>Plasmodium </it>species. Blood samples positive for <it>P. falciparum </it>were used for detecting the <it>pfcrt </it>T76 mutation using nested-PCR.</p> <p>Results</p> <p>The prevalence of <it>pfcrt </it>T76 mutation was 81.5% (66 of 81 isolates). Coastal areas/foothills had higher prevalence of <it>pfcrt </it>T76 mutation compared to highland areas (90.5% <it>vs </it>71.8%) (p = 0.031). The <it>pfcrt </it>T76 mutation had a significant association with parasitaemia (p = 0.045). Univariate analysis shows a significant association of <it>pfcrt </it>T76 mutation with people aged > 10 years (OR = 9, 95% CI = 2.3 - 36.2, p = 0.001), low household income (OR = 5, 95% CI = 1.3 - 19.5, p = 0.027), no insecticide spray (OR = 3.7, 95% CI = 1.16 - 11.86, p = 0.025) and not sleeping under insecticide treated nets (ITNs) (OR = 4.8, 95% CI = 1.38 - 16.78, p = 0.01). Logistic regression model confirmed age > 10 years and low household income as predictors of <it>pfcrt </it>T76 mutation in Yemen <it>P. falciparum </it>isolates.</p> <p>Conclusions</p> <p>The high prevalence of <it>pfcrt </it>T76 mutation in Yemen could be a predictive marker for the prevalence of <it>P. falciparum </it>CQR. This finding shows the necessity for an in-vivo therapeutic efficacy test for CQ.<it> P. falciparum </it>CQR should be addressed in the national strategy to control malaria.</p

    Host candidate gene polymorphisms and clearance of drug-resistant Plasmodium falciparum parasites

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    Resistance to anti-malarial drugs is a widespread problem for control programmes for this devastating disease. Molecular tests are available for many anti-malarial drugs and are useful tools for the surveillance of drug resistance. However, the correlation of treatment outcome and molecular tests with particular parasite markers is not perfect, due in part to individuals who are able to clear genotypically drug-resistant parasites. This study aimed to identify molecular markers in the human genome that correlate with the clearance of malaria parasites after drug treatment, despite the drug resistance profile of the protozoan as predicted by molecular approaches

    A systematic review and meta-analysis of evidence for correlation between molecular markers of parasite resistance and treatment outcome in falciparum malaria

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    <p>Abstract</p> <p>Background</p> <p>An assessment of the correlation between anti-malarial treatment outcome and molecular markers would improve the early detection and monitoring of drug resistance by <it>Plasmodium falciparum</it>. The purpose of this systematic review was to determine the risk of treatment failure associated with specific polymorphisms in the parasite genome or gene copy number.</p> <p>Methods</p> <p>Clinical studies of non-severe malaria reporting on target genetic markers (SNPs for <it>pfmdr1</it>, <it>pfcrt</it>, <it>dhfr</it>, <it>dhps</it>, gene copy number for <it>pfmdr1</it>) providing complete information on inclusion criteria, outcome, follow up and genotyping, were included. Three investigators independently extracted data from articles. Results were stratified by gene, codon, drug and duration of follow-up. For each study and aggregate data the random effect odds ratio (OR) with 95%CIs was estimated and presented as Forest plots. An OR with a lower 95<sup>th </sup>confidence interval > 1 was considered consistent with a failure being associated to a given gene mutation.</p> <p>Results</p> <p>92 studies were eligible among the selection from computerized search, with information on <it>pfcrt </it>(25/159 studies), <it>pfmdr1 </it>(29/236 studies), <it>dhfr </it>(18/373 studies), <it>dhps </it>(20/195 studies). The risk of therapeutic failure after chloroquine was increased by the presence of <it>pfcrt </it>K76T (Day 28, OR = 7.2 [95%CI: 4.5–11.5]), <it>pfmdr1 </it>N86Y was associated with both chloroquine (Day 28, OR = 1.8 [95%CI: 1.3–2.4]) and amodiaquine failures (OR = 5.4 [95%CI: 2.6–11.3, p < 0.001]). For sulphadoxine-pyrimethamine the <it>dhfr </it>single (S108N) (Day 28, OR = 3.5 [95%CI: 1.9–6.3]) and triple mutants (S108N, N51I, C59R) (Day 28, OR = 3.1 [95%CI: 2.0–4.9]) and <it>dhfr</it>-<it>dhps </it>quintuple mutants (Day 28, OR = 5.2 [95%CI: 3.2–8.8]) also increased the risk of treatment failure. Increased <it>pfmdr1 </it>copy number was correlated with treatment failure following mefloquine (OR = 8.6 [95%CI: 3.3–22.9]).</p> <p>Conclusion</p> <p>When applying the selection procedure for comparative analysis, few studies fulfilled all inclusion criteria compared to the large number of papers identified, but heterogeneity was limited. Genetic molecular markers were related to an increased risk of therapeutic failure. Guidelines are discussed and a checklist for further studies is proposed.</p
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