Principal role of dihydropteroate synthase mutations in mediating resistance to sulfadoxine-pyrimethamine in single-drug and combination therapy of uncomplicated malaria in Uganda.

Antimalarial resistance to sulfadoxine-pyrimethamine (SP) is mediated by mutations in the dihydrofolate reductase (dhfr) and dihydropteroate synthase (dhps) genes. However, the relative importance of different mutations is incompletely understood and has not been studied with combination therapy. Samples from 812 patients treated for uncomplicated malaria in Kampala, Uganda were tested for the presence of mutations commonly found in Africa. The dhps Glu-540 mutation was the strongest independent predictor of treatment failure. The dhfr Arg-59 mutation was only predictive of treatment failure in the presence of the dhps Glu-540 mutation. Comparing combination regimens with SP monotherapy, the addition of chloroquine to SP did not improve efficacy, the addition of artesunate lowered the risk of treatment failure only for infections with both the dhfr Arg-59 and dhps Glu-540 mutations, and the addition of amodiaquine lowered this risk for all dhfr/dhps mutation patterns. The dhps Glu-540 mutation played a principal role and the dhfr Arg-59 mutation a secondary role in mediating resistance to SP alone and in combination

Glucose-6-phosphate dehydrogenase status and risk of hemolysis in Plasmodium falciparum-infected African children receiving single-dose primaquine.

Glucose-6-phosphate dehydrogenase (G6PD) enzyme function and genotype were determined in Ugandan children with uncomplicated falciparum malaria enrolled in a primaquine trial after exclusion of severe G6PD deficiency by fluorescent spot test. G6PD A- heterozygotes and hemizygotes/homozygotes experienced dose-dependent lower hemoglobin concentrations after treatment. No severe anemia was observed

THIDIAZURON IMPROVES ADVENTITIOUS BUD AND SHOOT REGENERATION IN RECALCITRANT SWEETPOTATO

Induction of adventitious buds and shoots from intact leaves and stem internode segments of two recalcitrant Ugandan sweetpotato ( Ipomoea batatas L.) cultivars was investigated in vitro on Murashige and Skoog (MS) medium, supplemented with 3 different levels (0.5, 2.0 and 4.0 \u3bcM) of Thidiazuron (TDZ). Shoots were regenerated in all TDZ concentrations in cvs. Kyebandula and Bwanjule. The inclusion of 0.25 \u3bcM \u3b1-Naphthalene acetic acid (NAA) in MS medium, containing TDZ (0.5 \u3bcM), improved shoot regeneration frequency from 12.1 to 22.6% for cv. Kyebandula stems and from 21.61 to 42.9% for cv. Bwanjule stems. However, there was about 10% reduction in adventitious bud induction frequency for both cultivars, when NAA was included in the medium. The highest frequency (66.7%) of adventitious bud induction was achieved from stem explants of cv. Kyebandula. The conversion of adventitious buds into shoots was improved when TDZ was reduced or completely removed in subsequent stages of culture. The number of explants forming shoots was significantly (P<0.001) higher when stem explants were cultured for 7 days on TDZ-supplemented MS medium before transfer to TDZfree MS medium supplemented with NAA. Stem internode pieces from position 3 were the best (70.0%) in adventitious bud formation. However, most buds (76.2%) were not converted to shoots. The most important application of the de novo regeneration protocol developed in this study is in genetic transformation for improvement of sweetpotato productivity.L\u2019 induction des bourgeons adventices et des pousses \ue0 partir des feuilles intacts et des tiges des segments internodes de deux patates douces ( Ipomoea batatas L.) Ugandaises recalcitrantes \ue9tait \ue9tudi\ue9e en milieu in vitro sur le m\ue9dia Murashige et Skoog (MS) suppl\ue9ment\ue9 avec 3 niveaux diff\ue9rents (0.5, 2.0 et 4.0 \u3bcM) de Thidiazuron (TDZ). Les pousses \ue9taient r\ue9g\ue9n\ue9r\ue9es dans toutes les concentrations TDZ dans les cvs. Kyebandula et Bwanjule. L\u2019inclusion de 0.25 \u3bcM \u3b1-Naphthal\ue8ne d\u2019 acide ac\ue9tique (NAA) dans le m\ue9dia MS contenant le TDZ (0.5 \u3bcM) a am\ue9lior\ue9 la fr\ue9quence de la r\ue9n\ue9g\ue9n\ue9ration des pousses de 12.1 \ue0 22.6% pour les pousses cv. Kyebandula et de 21.61 \ue0 42.9% pur les pousses cv. Bwanjule. Cependant, il y a eu environ 10% de r\ue9duction en termes de la fr\ue9quence d\u2019induction des bourgeons adventices pour les deux cultivars lorsque NAA \ue9tait inclu dans le m\ue9dia. La fr\ue9quence la plus \ue9lev\ue9e (66.7%) d\u2019induction des bourgeons adventices \ue9tait r\ue9alis\ue9e des explants des tiges de cv. Kyebandula. La conversion des bourgeons adventices en pousses \ue9tait am\ue9lior\ue9e lorsque TDZ \ue9tait r\ue9duit ou compl\ue8tement enlev\ue9 des \ue9tapes de cultures subs\ue9quentes. Le nombre d\u2019explants formant les pousses \ue9tait significativement (P<0.001) sup\ue9rieur lorsque les explants des tiges \ue9taient cultiv\ue9s pendant 7 jours sur le m\ue9dia MS suppl\ue9ment\ue9 par TDZ avant le transfert dans le m\ue9dia MS sans TDZ avec pour suppl\ue9ment NAA. Les morceaux de tiges internodes de la position 3 \ue9taient le meilleur (70.0%) en formation de bourgeons adventices. Cependant, plus de bourgeons (76.2%) n\u2019\ue9taient pas converties en pousses. L\u2019application la plus importante du protocol de la r\ue9g\ue9n\ue9ration de novo d\ue9v\ue9lopp\ue9e dans cette \ue9tude reside dans la transformation g\ue9n\ue9tique pour l\u2019am\ue9lioration de la productivit\ue9 de la patate douce

Reproducibility of CSF quantitative culture methods for estimating rate of clearance in cryptococcal meningitis.

Quantitative cerebrospinal fluid (CSF) cultures provide a measure of disease severity in cryptococcal meningitis. The fungal clearance rate by quantitative cultures has become a primary endpoint for phase II clinical trials. This study determined the inter-assay accuracy of three different quantitative culture methodologies. Among 91 participants with meningitis symptoms in Kampala, Uganda, during August-November 2013, 305 CSF samples were prospectively collected from patients at multiple time points during treatment. Samples were simultaneously cultured by three methods: (1) St. George's 100 mcl input volume of CSF with five 1:10 serial dilutions, (2) AIDS Clinical Trials Group (ACTG) method using 1000, 100, 10 mcl input volumes, and two 1:100 dilutions with 100 and 10 mcl input volume per dilution on seven agar plates; and (3) 10 mcl calibrated loop of undiluted and 1:100 diluted CSF (loop). Quantitative culture values did not statistically differ between St. George-ACTG methods (P= .09) but did for St. George-10 mcl loop (P< .001). Repeated measures pairwise correlation between any of the methods was high (r≥0.88). For detecting sterility, the ACTG-method had the highest negative predictive value of 97% (91% St. George, 60% loop), but the ACTG-method had occasional (∼10%) difficulties in quantification due to colony clumping. For CSF clearance rate, St. George-ACTG methods did not differ overall (mean -0.05 ± 0.07 log10CFU/ml/day;P= .14) on a group level; however, individual-level clearance varied. The St. George and ACTG quantitative CSF culture methods produced comparable but not identical results. Quantitative cultures can inform treatment management strategies

TRANSIENT EXPRESSION OF \u3b2-GLUCURONIDASE IN RECALCITRANT UGANDAN SWEETPOTATO AND PUTATIVE TRANSFORMATION WITH TWO CRY GENES

Sweetpotato ( Ipomoea batatas Lam.) has high potential to contain hunger, malnutrition and poverty in sub-Saharan Africa (SSA), since it gives early yield with few inputs. However, productivity of the crop in Africa is very low due to various challenges, such as severe viral diseases and increasing attacks by sweetpotato weevils, Cylas puncticollis and C. brunneus . Effective resistance to weevils has not been identified in the sweetpotato gene pool. On the other hand, the weevil-resistance genes, cry7Aa1 and cry3Ca1 were assembled into a plasmid vector for use in genetic transformation of African sweetpotato cultivars. The parameters for efficient transfer of these genes and the conditions for de novo regeneration optimised in preliminary studies were used in the genetic transformation of Ugandan landrace \u2018Kyebandula\u2019 with Agrobacterium tumefaciens EHA 105 harbouring the plasmid pCIP84, which contains cry7Aa1, cry3Ca1 and nptII in its T-DNA. Fifty-four percent of the explants formed adventitious buds. With a mean of 7 buds formed per explant, 6.0% explants formed shoots with a mean of one shoot per explant for those explants that formed shoots on medium containing 50 mg L-1 kanamycin as a selection agent. PCR analysis using primers for cry7Aa1 showed that the transformation efficiency could be as high as 2%. These data highlight the potential of genetic transformation in transferring resistance genes and pave way for enhancement of food security through production of adapted sweetpotato weevil resistant cultivars.La patate douce ( Ipomoea batatas Lam.) a un potentiel de contenir la faim, la malnutrition et la pauvret\ue9 en Afrique Sub Saharienne \ue9tant donn\ue9 sa pr\ue9cocit\ue9 et son grand rendement avec peu d\u2019intrants. Par ailleurs, sa productivit\ue9 est trop basse due aux diverses contraintes li\ue9es aux maladies virales et attaques sans cesse croissante des charan\ue7ons Cylas puncticollis and C. brunneus . Une r\ue9sistance efficace au charan\ue7on n\u2019a pas encore \ue9t\ue9 identifi\ue9e dans la collection des g\ue8nes de la patate douce. D\u2019autre part, les g\ue8nes de r\ue9sistance aux charan\ue7ons, cry7Aa1 et cry3Ca1 \ue9taient assembl\ue9es un vecteur de plasmide pour utilisation dans la transformation g\ue9n\ue9tique des cultivars de patate douces africaines. Les param\ue8tres pour transfert d\u2019efficacit\ue9 de ces g\ue8nes et les conditions de r\ue9g\ue9n\ue9ration de novo optimis\ue9es dans des \ue9tudes pr\ue9liminaires \ue9taient utilis\ue9es dans la transformation g\ue9n\ue9tique du landrace ougandais \u2018Kyebandula\u2019avec l\u2019 Agrobacterium tumefaciens EHA 105 portant le plasmide pCIP84, contenant les cry7Aa1, cry3Ca1 et nptII dans son T-ADN. Cinquante quatre pourcent des explants ont form\ue9 des bourgeons adventices. Avec une moyenne de 7 bourgeons par explant, 6.0% d\u2019explants ont form\ue9 des tiges avec une moyenne d\u2019une tige par explant pour ces explants qui ont form\ue9 des tiges sur le media contenant 50 mg L-1 de kanamycine comme agent de s\ue9lection. L\u2019analyse par PCR utilisant des primers pour cry7Aa1 a montr\ue9 que la transformation efficace pourrait \ueatre aussi \ue9lev\ue9e que 2%. Ces donn\ue9es soulignent le potentiel de transformation g\ue9n\ue9tique dans le transfert des g\ue8nes de r\ue9sistance et un moyen d\u2019am\ue9liorer la s\ue9curit\ue9 alimentaire \ue0 travers la production des cultivars de r\ue9sistance adapt\ue9e aux charan\ue7ons de la patate douce

Expression of a barley cystatin gene in maize enhances resistance against phytophagous mites by altering their cysteine-proteases

Phytocystatins are inhibitors of cysteine-proteases from plants putatively involved in plant defence based on their capability of inhibit heterologous enzymes. We have previously characterised the whole cystatin gene family members from barley (HvCPI-1 to HvCPI-13). The aim of this study was to assess the effects of barley cystatins on two phytophagous spider mites, Tetranychus urticae and Brevipalpus chilensis. The determination of proteolytic activity profile in both mite species showed the presence of the cysteine-proteases, putative targets of cystatins, among other enzymatic activities. All barley cystatins, except HvCPI-1 and HvCPI-7, inhibited in vitro mite cathepsin L- and/or cathepsin B-like activities, HvCPI-6 being the strongest inhibitor for both mite species. Transgenic maize plants expressing HvCPI-6 protein were generated and the functional integrity of the cystatin transgene was confirmed by in vitro inhibitory effect observed against T. urticae and B. chilensis protein extracts. Feeding experiments impaired on transgenic lines performed with T. urticae impaired mite development and reproductive performance. Besides, a significant reduction of cathepsin L-like and/or cathepsin B-like activities was observed when the spider mite fed on maize plants expressing HvCPI-6 cystatin. These findings reveal the potential of barley cystatins as acaricide proteins to protect plants against two important mite pests

THE ROLE OF INTERDEPENDENCE IN THE MICRO-FOUNDATIONS OF ORGANIZATION DESIGN: TASK, GOAL, AND KNOWLEDGE INTERDEPENDENCE

Interdependence is a core concept in organization design, yet one that has remained consistently understudied. Current notions of interdependence remain rooted in seminal works, produced at a time when managers’ near-perfect understanding of the task at hand drove the organization design process. In this context, task interdependence was rightly assumed to be exogenously determined by characteristics of the work and the technology. We no longer live in that world, yet our view of interdependence has remained exceedingly task-centric and our treatment of interdependence overly deterministic. As organizations face increasingly unpredictable workstreams and workers co-design the organization alongside managers, our field requires a more comprehensive toolbox that incorporates aspects of agent-based interdependence. In this paper, we synthesize research in organization design, organizational behavior, and other related literatures to examine three types of interdependence that characterize organizations’ workflows: task, goal, and knowledge interdependence. We offer clear definitions for each construct, analyze how each arises endogenously in the design process, explore their interrelations, and pose questions to guide future research

Technical report on the environmental monitoring of the cage area at the Source of the Nile (SON) Fish Farm for Quarter 4: October – December 2017

The monitoring of water quality and biotic communities at Source of the Nile (SON) fish farm area, for quarter 4 (October – December) was undertaken in December 2017. The activity aimed at assessing possible changes in the water environment at SON cage area. The following parameters were assessed: water physico-chemicals and nutrients, algae, zooplankton, benthic macro invertebrates, and fish communities. Total depth was above 5.0 m (range: 5.63 – 9.74 m) at all sampled points and decreased towards the downstream of cages. Water transparency ranged from 1.26 – 1.48 in the cage area and 1.08 to 1.34 m away from the cages. Within the cage area, Dissolved Oxygen ranged from 5.7 – 6.4 mg/L at the surface, and 5.1 – 6.4 mg/L at the bottom, while in the non-cage areas, the range was 5.5 – 7.5 mg/L at the surface and 2.6 – 7.0 mg/L at the bottom. Temperature ranged from 27.0 – 28.0 o C at the surface and 25.5 – 27.5 o C at the bottom waters for all sites, and were within the optimal range (25 – 32 o C). pH in both surface and bottom waters was above 7.0 (range: 7.5 – 9.2) at all sites. Conductivity within cage area ranged from 100.5 – 102.6 μScm-1 in surface water and 101.8 – 112.1 μScm-1 in bottom water. In the non-cage areas conductivity ranged from 11.0 – 104.4 μScm-1 in surface water and 100.2 – 110.0 μScm-1 at the bottom. Ammonium nitrogen concentration during December was less than 0.02 mg/L at all sites (0.007 – 0.018 mg/L within the cage sites, and 0.012 – 0.019 mg/L in the non-cage sites). Nitrite nitrogen ranged from 0.002 – 0.169 mg/L in the cage area, and 0.003 – 0.057 mg/L in the non-cage areas. Similar to previous records of June and September 2017, nitrate nitrogen concentration generally increased towards the downstream site, being lowest at RPT (0.041 mg/L) and highest at DSC (0.204 mg/L). Soluble reactive phosphorus was less than 0.005 mg/L at all sites, and varied within narrow margin (range: 0.003 – 0.0048 mg/L in cage sites, and 0.0032 – 0.0047 mg/L in non-cage sites). The TP concentration ranged from 0.085 – 0.107 mg/L in the cages, and 0.090 – 0.118 mg/L in the non-cage sites and was higher than recorded in September (0.038 – 0.044 mg/L in the cages and 0.04 to 0.109 mg/L away from cages). Total nitrogen concentration was in the range of 0.138 – 0.553 mg/L within cage area and 0.421 – 0.513 mg/L in non-cage areas. The concentration of TSS ranged from 0.76 – 4.33 mg/L in the cage area and 0.57 – 2.76 mg/L in the non-cage areas. The phytoplankton community was composed of blue-green algae, green algae and diatoms, dominated by blue-green algae. The abundance of algae was higher in the non-cage areas (mean:7.20 ± 2.14 mm3L-1, Range: 5.15 – 10.20 mm3L-1) than recorded in the cage areas (mean: 6.0 ± 0.71 mm3L-1, Range: 5.30 – 6.98 mm3L-1), similar to observations of September 2017 (5.6 mm3L-1 in the non-cage sites). At all sampled points, blue-green algae contributed >70% of total abundance. Total zooplankton abundance ranged from 982,213 – 1,310,830 ind.m-2 in the non-cage sites, and 740,601 – 1,503,130 ind.m-2 in the cage areas. Similar to observations of September 2017, the upper cage site (WIC3 and WIC4) presented lower zooplankton abundance (mean: 788,954 ± 68,381 ind.m-2) when compared to the lower cage site with mean abundance of 1,128,232 ± 530,186 ind.m-2. Like in the previous sampling periods, copepods were the numerically dominant group (92.69 – 97.22 % of total zooplankton abundance) at all sampled points, with no major differences between cage and non-cage areas. The high abundance of copepods was attributed to the abundance of the juvenile stages (copepodites and Nauplius larvae) which contributed 83.72 – 92.78% of the total zooplankton abundance and this was mainly due to the Nauplius larvae (66.4 – 83.2 %). Cladocera relative abundance ranged from 0.32 – 3.98% while that of rotifers ranged from 1.55 – 3.74%. The macro-benthic community comprised molluscs, annelids and arthropods. Taxa richness ranged from 5 – 11 taxa in the cage area, and 7 – 9 taxa in the non-cage areas. The abundance of benthic invertebrates within the cage area ranged from 1,134 – 2,416 ind.m-2 and this was higher than previously recorded in September (294 – 1,415 ind.m-2). In the non-cage sites abundance was in the range of 420 – 3,992 ind.m-2. Oligochaete annelids which are reported to be very tolerant to pollution contributed 0 - 28 % of the abundance of benthos at cage sites and 3 - 20% at the non-cage sites. Diptera made the greatest contribution at almost all sites, with the percent abundance being higher in non-cage sites (40 – 86%) than what was recorded in the cage sites (37 – 82%). Chironomus spp. and Chaoborus sp. were the main contributors to the observed Diptera abundance at all sites. Six fish species, including haplochromines (Nkejje) as a single species group, were recorded in the vicinity of the cages during December 2017. Five fish species were recorded from upstream the cage site, four species from within cage area, and two species from downstream the cages. Overall mean catch rates were 1.8 fish/net/night and 148.6g/net/night compared to 1.7 fish/net/night and 175.4g/net/night recorded in September 2017. By weight, catch rates in December 2017 were highest upstream the cage site (312.1g/net/night) and also by numbers (3.1 fish/net/night). Four species of haplochromines were recorded in the vicinity of the cages during the survey of December 2017 compared to six species recorded in September 2017. The overall catch rate for the haplochromines, in December 2017 was 1.7fish/net/night and 27.5g/net/night compared to 3.4 fish/net/night and 62.3g/net/night recorded in the previous survey of September 2017. Among the fish species examined during December 2017 survey, most of the haplochromine cichlids (88.9%) were mature but only 50% breeding. Only one specimen of L. niloticus was mature and breeding. All S. afrofischeri and S. victoriae specimens examined were mature and in breeding condition while M. kannume was immature. The diet of fishes encountered comprised mostly of fish and insects, which are known natural foods of the fish species. Infection by fish parasites during the survey of December 2017 was not noticed in any fish recorded from the experimental gillnets. The overall observation on concentrations of nutrients, levels of physico-chemical variables, and biotic communities indicated minimal impact of cages on water quality. The farm should therefore continue adhering to the best environmentally sustainable aquaculture practices, especially continuing with fallowing or rotation of cages to allow resident organisms maintain their natural population densities, distribution and community structure in the area; reducing excess uneaten feed and other suspended materials which would impact on nutrient status and biota; as well as wise use of any chemicals in the area