Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99


Any time

2019 ( 13 )

2018 ( 12 )

2017 ( 12 )

2016 ( 17 )

Custom range...

Search Results: 1 - 10 of 6873 matches for " Nelson Kalema "
All listed articles are free for downloading (OA Articles)
Page 1 /6873
Display every page Item
Oral Antimicrobial Rinse to Reduce Mycobacterial Culture Contamination among Tuberculosis Suspects in Uganda: A Prospective Study
Nelson Kalema, Saskia Den Boon, Adithya Cattamanchi, J. Lucian Davis, Alfred Andama, Winceslaus Katagira, Charles Everett, Nicholas Walter, Patrick Byanyima, Sylvia Kaswabuli, William Worodria, Laurence Huang
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0038888
Abstract: Rationale Contamination by bacterial or fungal organisms reduces the effectiveness of mycobacterial culture for diagnosis of pulmonary tuberculosis (TB). We evaluated the effect of an anti-microbial and an anti-fungal oral rinse prior to expectoration on culture-contamination rates. Methods We enrolled a consecutive random sample of adults with cough for ≥2 weeks and suspected TB admitted to Mulago Hospital (Kampala, Uganda) between October 2008 and June 2009. We randomly assigned patients to oral rinse (60 seconds with chlorhexidine followed by 60 seconds with nystatin) vs. no oral rinse prior to initial sputum collection. Uganda National Tuberculosis Reference Laboratory technicians blinded to the method of sputum collection (with or without oral rinse) processed all sputum specimens for smear microscopy (direct Ziehl-Neelsen) and mycobacterial culture (Lowenstein-Jensen media). Results Of 220 patients enrolled, 177 (80%) were HIV-seropositive (median CD4-count 37 cells/uL, IQR 13–171 cells/uL). Baseline characteristics were similar between patients in the oral-rinse (N = 110) and no oral-rinse (N = 110) groups. The proportion of contaminated cultures was significantly lower in the oral-rinse group compared to the no oral-rinse group (4% vs. 15%, risk difference ?11%, 95% CI ?18 to ?3%, p = 0.005). Oral rinse significantly reduced the proportion of contaminated cultures among HIV-infected patients (3% vs. 18%, risk difference ?14%, 95% CI ?23 to ?6%, p = 0.002) but not HIV-uninfected (6% vs. 4%, risk difference 2%, 95% CI ?12 to +15%, p = 0.81) patients. However, the proportion of smear-positive specimens (25% vs. 35%, p = 0.10) and culture-positive specimens (48% vs. 56%, p = 0.24) were lower in the oral-rinse compared to the no oral-rinse group, although the differences were not statistically significant. Conclusions Oral rinse prior to sputum expectoration is a promising strategy to reduce mycobacterial culture contamination in areas with high HIV prevalence, if strategies can be devised to reduce the adverse impact of oral rinse on smear- and culture-positivity.
Impact of Xpert MTB/RIF Testing on Tuberculosis Management and Outcomes in Hospitalized Patients in Uganda
Christina Yoon, Adithya Cattamanchi, J. Lucian Davis, William Worodria, Saskia den Boon, Nelson Kalema, Winceslaus Katagira, Sylvia Kaswabuli, Cecily Miller, Alfred Andama, Heidi Albert, Pamela Nabeta, Christen Gray, Irene Ayakaka, Laurence Huang
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0048599
Abstract: Rationale The clinical impact of Xpert MTB/RIF for tuberculosis (TB) diagnosis in high HIV-prevalence settings is unknown. Objective To determine the diagnostic accuracy and impact of Xpert MTB/RIF among high-risk TB suspects. Methods We prospectively enrolled consecutive, hospitalized, Ugandan TB suspects in two phases: baseline phase in which Xpert MTB/RIF results were not reported to clinicians and an implementation phase in which results were reported. We determined the diagnostic accuracy of Xpert MTB/RIF in reference to culture (solid and liquid) and compared patient outcomes by study phase. Results 477 patients were included (baseline phase 287, implementation phase 190). Xpert MTB/RIF had high sensitivity (187/237, 79%, 95% CI: 73–84%) and specificity (190/199, 96%, 95% CI: 92–98%) for culture-positive TB overall, but sensitivity was lower (34/81, 42%, 95% CI: 31–54%) among smear-negative TB cases. Xpert MTB/RIF reduced median days-to-TB detection for all TB cases (1 [IQR 0–26] vs. 0 [IQR 0–1], p<0.001), and for smear-negative TB (35 [IQR 22–55] vs. 22 [IQR 0–33], p = 0.001). However, median days-to-TB treatment was similar for all TB cases (1 [IQR 0–5] vs. 0 [IQR 0–2], p = 0.06) and for smear-negative TB (7 [IQR 3–53] vs. 6 [IQR 1–61], p = 0.78). Two-month mortality was also similar between study phases among 252 TB cases (17% vs. 14%, difference +3%, 95% CI: ?21% to +27%, p = 0.80), and among 87 smear-negative TB cases (28% vs. 22%, difference +6%, 95% CI: ?34 to +46%, p = 0.77). Conclusions Xpert MTB/RIF facilitated more accurate and earlier TB diagnosis, leading to a higher proportion of TB suspects with a confirmed TB diagnosis prior to hospital discharge in a high HIV/low MDR TB prevalence setting. However, our study did not detect a decrease in two-month mortality following implementation of Xpert MTB/RIF possibly because of insufficient powering, differences in empiric TB treatment rates, and disease severity between study phases.
Larvicidal Activity of Aquatic Carnivorous Plants on Anopheles Mosquito Larval Stages
Jasper Ogwal-Okeng,James Kalema,Mary Namaganda,Aloysius Lubega,Moses Zziwa,Godfrey S. Bbosa
Research Journal of Biological Sciences , 2012, DOI: 10.3923/rjbsci.2011.436.439
Abstract: Malaria is still a major killer disease in tropical Africa, contributing 10% to the overall disease burden. The Plasmodium parasites are mainly transmitted by the mosquitoes Anopheles gambiae and A. funestus in Uganda. Approaches for malaria vector control include denial of breeding ground near human dwellings, use of insecticide treated nets and chemical spraying. Chemical approaches raise challenges of vector resistance, non-target specificity and ecological and human health concerns. In view of these draw backs, this research explored the effects of carnivorous plants of the genera; Aldrovanda vesiculosa (A. vesiculosa) and Utricularia reflexa (U. reflexa) against the fourth instar larvae of Anopheles mosquito. A. vesiculosa and U. reflexa are aquatic carnivorous plants that derive some or most of their nutrients from trapping and consuming animals or protozoans, typically insects and other arthropods. Aldrovanda and Utricularia grow in water and have bladder traps that suck in prey by generating an internal vacuum. Some of the prey may include mosquito larvae from the breeding sites. The plants were collected from the wild and allowed to grow in the laboratory. Larvicidal bioassays were done to determine their effectiveness to ingest and reduce the population of mosquito larvae in the laboratory. The carnivorous plants remarkably reduced the larvae population in 5 days. All the 20 larvae in each of the control vessels remained alive and active during the test period. It was concluded that aquatic carnivorous plants are potential biological agents for ecologically sound and sustainable strategy for controlling malaria in Uganda.
A preliminary investigation of tuberculosis and other diseases in African buffalo (Syncerus caffer) in Queen Elizabeth National Park, Uganda
G. Kalema-Zikusoka,R.G. Bengis,A.L. Michel,M.H. Woodford
Onderstepoort Journal of Veterinary Research , 2010, DOI: 10.4102/ojvr.v72i2.210
Abstract: A survey to determine the prevalence of bovine tuberculosis caused by Mycobacterium bovis and certain other infectious diseases was conducted on 42 free-ranging African buffaloes, (Syncerus caffer) from May to June 1997 in the Queen Elizabeth National Park, Uganda. Using the gamma interferon test, exposure to M. bovis was detected in 21.6 % of the buffaloes. One dead buffalo and an emaciated warthog (Phacochoerus aethiopicus) that was euthanased, were necropsied; both had miliary granulomas from which M. bovis was isolated. None of the buffaloes sampled in Sector A of the park, which has no cattle interface, tested positive for bovine tuberculosis (BTB) exposure. The prevalence and distribution of BTB does not appear to have changed significantly since the 1960s, but this may be due to fluxes in the buffalo population. Serological testing for foot-and-mouth disease (FMD) demonstrated positive exposure of 57.1% of the buffaloes sampled, with types A, O and SAT 1-3, which is the first known report of FMD antibodies to A and O types in free ranging African buffaloes. Foot-and-mouth disease virus types SAT 1 and SAT 3 were isolated from buffalo probang samples. Two percent of the buffaloes had been exposed to brucellosis. None of the buffaloes tested had antibodies to rinderpest, leptospirosis or Q fever.
Oceans, Ice & Snow and CO2 Rise, Swing and Seasonal Fluctuation  [PDF]
Michael D. Nelson, David B. Nelson
International Journal of Geosciences (IJG) , 2016, DOI: 10.4236/ijg.2016.710092
Abstract: Carbon dioxide rise, swing and spread (seasonal fluctuations) are addressed in this study. Actual CO2 concentrations were used rather than dry values. The dry values are artificially higher because water vapor must be removed in order for the NDIR instrument to work and is not factored back into the reported numbers. Articles addressing these observations express opinions that are divergent and often conflicting. This investigation resolves many of those inconsistencies. The data were obtained from many measuring stations at various latitudes since 1972 and then graphical compared to changes in sea temperatures, fossil fuel emissions, humidity, and seasonal ice and snow changes. In analyzing the data, various parameters were addressed including: variability, R squared curve values, correlations between curves, residence times, absorption percentages, and Troposphere effects. Mass balance calculations were also made to corroborate viability. The CO2 “rise” over a 33-year period from a slight ocean temperature increase (0.7°F) contributed 2.3 percent of the total rise while fossil fuel emissions contributed 1.5 percent. The overwhelming majority (60 ppmv, 96%+) was caused by other factors including ocean and land biology as well potential errors in fundamental hypotheses. With respect to “spread” (seasonal CO2 fluctuations) at the Polar Circles, graphical analysis with high correlations supported by mass balance calculations confirm that ice and snow are the primary cause and explain why the concentrations are the highest at these cold locations. The global variations in “swing” remain uncertain.
Ciprofloxacin Cardiotoxicity and Hepatotoxicity in Humans and Animals  [PDF]
Elias Adikwu, Nelson Brambaifa
Pharmacology & Pharmacy (PP) , 2012, DOI: 10.4236/pp.2012.32028

Ciprofloxacin is generally well tolerated; the most common adverse effects include gastro intestinal tract, central nervous system and hematological system effects. Recently rising cases of Ciprofloxacin associated toxicity have been reported. Experiment using animal models and clinical experience showed that Ciprofloxacin induced cardiotoxicity is marked by increase QT and QTC interval and prolonged action potential duration. This increases the risk of arrhythmia (tosarde de pointes). Ciprofloxacin induced cardiotoxic effect could be associated with blocking cardiac voltage—gated potassium channels particularly the rapid component (IKr) of the delayed rectifier potassium current. Drug interaction with inhibitors of Cytochrome P450 (CYP) mediated metabolism could be one of the underlying mechanisms. Several cases of Ciprofloxacin induced hepatoxicity have been also reported. These were characterized by extensive hepatocellular necrosis, mixed inflammatory infiltrate and abundant esinophils in the liver. Elevated liver enzymes which include serum aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, and gramma-glutamyltranferase

Modification of the Newtonian Dynamics in ΛFRW-Cosmology an Alternative Approach to Dark Matter and Dark Energy  [PDF]
Nelson Falcón
Journal of Modern Physics (JMP) , 2013, DOI: 10.4236/jmp.2013.48A003

Modified Newtonian Dynamics (MoND) is an empirically motivated modification of Newtonian gravity at largest scales, to explain rotation curves of galaxies, as an alternative to nonbaryonic dark matter. But MoND theories can hardly connect to the formalism of relativistic cosmology type Friedmann-Robertson-Walker. Presently work intends the existence of one scalar potential, with non gravitational origin, that would solve these problems. This potential Yukawa type inverse is build starting from a specular reflection of the potential of Yukawa: null in very near solar system, slightly attractiveness in ranges of interstellar distances, very attractiveness in distance ranges comparable to galaxies cluster and repulsive to cosmic scales. The consequences of this potential are discussed, through Cosmological Model Tipe Friedmann-Roberston-Walker with cosmological term in function of the distance (lambda like function of r). In the cosmological model so raised the critical density of matter is consistent with the observed density does not include dark matter, MoND theory is deduced for interstellar scales and consequently would explain rotation curves. Also it is shown that Yukawa type inverse does not alter the predictions of the Cosmic Microwave Background neither the primordial nucleosynthesis in early universe; and can be explain the large-scale structure formation.

A Homeowner-Based Methodology for Economic Analysis of Energy-Efficiency Measures in Residences  [PDF]
Nelson Fumo, Roy Crawford
Open Journal of Energy Efficiency (OJEE) , 2013, DOI: 10.4236/ojee.2013.22013

Residential energy-efficiency measures, besides energy savings, provide opportunities for improvement of thermal comfort, air quality, lighting quality, and operation. However, all these benefits sometimes are not enough to convince a homeowner to pay the incremental cost associated with the energy-efficiency measure. The objective of this work is to develop a methodology for the economic evaluation of residential energy-efficiency measures that can simplify the economic analysis for the homeowner while taking into consideration all factors associated with the purchase, ownership, and selling of the house with the energy-efficiency measure. The methodology accounts for direct and indirect economic parameters associated to an energy-efficiency measure; direct parameters such as the mortgage interest and fuel price escalation rate, and indirect parameters such as savings account interest and marginal income tax rate. The methodology also considers different cases based on the service life of the energy-efficiency measure and loss of efficiency through a derating factor. To estimate the market value, the methodology uses the future energy cost savings instead of the cost of the EEM. Results from the methodology offer to homeowner annual net savings and net assets. The annual net savings gives the homeowner a measure of the annual positive cash flow that can be obtained from an energy-efficiency project; but more important, the net assets offer a measure of the added net wealth. To simplify and increase the use of the methodology by homeowners, the methodology has been implemented in an Excel tool that can be downloaded from the TxAIRE’s website.

Multiple Endemic Solutions in an Epidemic Hepatitis B Model without Vertical Transmission  [PDF]
Nelson Owuor Onyango
Applied Mathematics (AM) , 2014, DOI: 10.4236/am.2014.516242

This paper examines the dynamics of Hepatitis B via a Susceptible Exposed Infectious Recovered (SEIR) type epidemic model. Previous studies have shown that Hepatitis B is characterized by multiple endemic solutions, a matter which may be of concern in developing control strategies. We identify the possible causes of multiple endemic solutions in a Hepatitis B model and conclude that the dependance of the probability of carriage development  (q(Λ)) on the force of infection (Λ) is the main reason for multiple endemicity. Other factors such as a large proportion of infants that are not vaccinated (ω) may also enhance the possibility of multiple endemicity. The role of carriers may also play a key role in the possibility of such complex dynamics, i.e., when infectiousness of carriers-(α) is high, the probability of existence of multiple endemic equilibrium solutions is increased. In our arguments, the traditional reproduction number R0< 1 which we define here by a function G(0) < 1 does not imply stability of disease-free equilibrium.

Uniformly Bounded Set-Valued Composition Operators in the Spaces of Functions of Bounded Variation in the Sense of Riesz  [PDF]
Wadie Aziz, Nelson Merentes
International Journal of Modern Nonlinear Theory and Application (IJMNTA) , 2015, DOI: 10.4236/ijmnta.2015.44017
Abstract: We show that the lateral regularizations of the generator of any uniformly bounded set-valued composition Nemytskij operator acting in the spaces of functions of bounded variation in the sense of Riesz, with nonempty bounded closed and convex values, are an affine function.
Page 1 /6873
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.