Stage progression and neurological symptoms in Trypanosoma brucei rhodesiense sleeping sickness: role of the CNS inflammatory response

Background: Human African trypanosomiasis progresses from an early (hemolymphatic) stage, through CNS invasion to the late (meningoencephalitic) stage. In experimental infections disease progression is associated with neuroinflammatory responses and neurological symptoms, but this concept requires evaluation in African trypanosomiasis patients, where correct diagnosis of the disease stage is of critical therapeutic importance. Methodology/Principal Findings: This was a retrospective study on a cohort of 115 T.b.rhodesiense HAT patients recruited in Eastern Uganda. Paired plasma and CSF samples allowed the measurement of peripheral and CNS immunoglobulin and of CSF cytokine synthesis. Cytokine and immunoglobulin expression were evaluated in relation to disease duration, stage progression and neurological symptoms. Neurological symptoms were not related to stage progression (with the exception of moderate coma). Increases in CNS immunoglobulin, IL-10 and TNF-α synthesis were associated with stage progression and were mirrored by a reduction in TGF-β levels in the CSF. There were no significant associations between CNS immunoglobulin and cytokine production and neurological signs of disease with the exception of moderate coma cases. Within the study group we identified diagnostically early stage cases with no CSF pleocytosis but intrathecal immunoglobulin synthesis and diagnostically late stage cases with marginal CSF pleocytosis and no detectable trypanosomes in the CSF. Conclusions: Our results demonstrate that there is not a direct linkage between stage progression, neurological signs of infection and neuroinflammatory responses in rhodesiense HAT. Neurological signs are observed in both early and late stages, and while intrathecal immunoglobulin synthesis is associated with neurological signs, these are also observed in cases lacking a CNS inflammatory response. While there is an increase in inflammatory cytokine production with stage progression, this is paralleled by increases in CSF IL-10. As stage diagnostics, the CSF immunoglobulins and cytokines studied do not have sufficient sensitivity to be of clinical value

AGB subpopulations in the nearby globular cluster NGC 6397

It has been well established that Galactic Globular clusters (GCs) harbour more than one stellar population, distinguishable by the anti-correlations of light element abundances (C-N, Na-O, and Mg-Al). These studies have been extended recently to the asymptotic giant branch (AGB). Here we investigate the AGB of NGC 6397 for the first time. We have performed an abundance analysis of high-resolution spectra of 47 RGB and 8 AGB stars, deriving Fe, Na, O, Mg and Al abundances. We find that NGC 6397 shows no evidence of a deficit in Na-rich AGB stars, as reported for some other GCs - the subpopulation ratios of the AGB and RGB in NGC 6397 are identical, within uncertainties. This agrees with expectations from stellar theory. This GC acts as a control for our earlier work on the AGB of M 4 (with contrasting results), since the same tools and methods were used.Comment: 10 pages, 7 figures, 8 tables (2 online-only). Accepted for publication in MNRA

Central Nervous System Parasitosis and Neuroinflammation Ameliorated by Systemic IL-10 Administration in Trypanosoma brucei-Infected Mice

Peer reviewedPublisher PD

Productivity, Survival, and Movements of Female Moose in a Low-density Population, Northwest Territories, Canada

Moose (Alces alces andersoni) occur at low density (140-160 moose/1000 sq km) and are the most important game animal in much of the Mackenzie Valley, western Northwest Territories. Productivity and survival of 30 female moose (>=1.5 yr.) were studied from November 1985 through November 1988. Twenty-nine of these moose were radio-tracked for a total of 1039 relocations. Pregnancy rates were 96% for adult and 40% for yearling females. Most females returned to the same restricted area to calve each year. Mean newborn calf:female ratio and twinning rates were 1.2:1 and 31%, respectively. Mean annual female survival rate was 85%. Annual calf survival was high and stable (44±0.02%). Individual total home range size varied from 40 sq km to 942 sq km. Mean home range size for 29 moose was 174±31 sq km and 202±59 sq km for the 14 moose radio-tracked the entire three years of study. Fall home ranges were twice the size of winter and summer home ranges; seasonal ranges overlapped widely, indicating that these moose were non-migratory.Key words: moose, low density, productivity, movements, Mackenzie Valley, Northwest TerritoriesL'orignal (Alces alces andersoni) est présent à faible densité (140-160 orignaux/1000 km²) et constitue le gibier le plus important dans la plupart de la vallée du Mackenzie, à l'ouest des Territoires du Nord-Ouest. On a étudié la productivité et le taux de survie de 30 orignaux femelles (<= 1,5 ans) de novembre 1985 à novembre 1988. Vingt-neuf de ces orignaux ont été suivis par radio sur un total de 1039 déplacements. Les taux de gestation étaient de 96 p. cent pour les adultes et de 40 p. cent pour les femelles d'un an. La plupart des femelles retournaient chaque année mettre bas dans la même zone restreinte. Le rapport moyen mâle/femelle parmi les nouveau-nés était de 1,2 pour 1, et le pourcentage de jumeaux était de 30 p. cent. Le taux de survie annuel moyen des femelles était de 85 p. cent. Le taux de survie annuel des veaux était élevé et stable (44 ± 0,02 p. cent). Le territoire individuel total variait de 40 à 942 km². Le territoire moyen mesurait 174 ± 31 km² pour l'ensemble des 29 orignaux, et 202 ± 59 km² pour les 14 orignaux suivis par radio du début à la fin de la période triennale d'étude. Les territoires étaient deux fois plus étendus en automne qu'en hiver ou en été; les territoires saisonniers se recoupaient largement, ce qui indique que ces orignaux n'étaient pas migratoires.Mots clés: orignal, faible densité, productivité, mouvements, vallée du Mackenzie, Territoires du Nord-Ouest&nbsp

Evaluation of the airborne contamination levels in an intensive care unit over a 24 hour period

Airborne transmission of infectious microorganisms poses a critical threat to human health, particularly in the clinical setting where it is estimated that 10-33% of nosocomial infections are spread via the air. Within the clinical environment, microorganisms originating from the human respiratory tract or skin can become airborne by coughing and sneezing, and periods of increased activity such as bed and dressing changes, movement, staff rounds and visiting hours. Current knowledge of the clinical airborne microflora is limited and there is uncertainty surrounding the contribution of airborne microorganisms to the transmission of nosocomial infection. This study aims to establish an improved understanding of the variability in the dynamics and levels of airborne microbial contamination within an operational intensive care unit (ICU). Methods Environmental monitoring of airborne contamination levels was conducted in Glasgow Royal Infirmary ICU, in the open ward and in both occupied and unoccupied patient isolation rooms. Monitoring was performed using a sieve impactor air sampler, with 500 L air samples collected every 15 minutes over 10 hour (08:00-18:00 h) and 24 hour (08:00-08:00 h) periods. Samples were collected on tryptone soya agar (TSA) plates, and the bacterial contamination levels were recorded as CFU/m3 of air. An activity log was also collated over the 10 hour and 24 hour sampling periods in order to record any activity occurring in the ward/room that might contribute to spikes in airborne contamination levels. Results Results highlight the degree of variability in levels of airborne contamination over the course of both a working day and a 24 hour period in a hospital ICU. A high degree of variability was observed across the 24 hour period, with counts ranging from 12-510 CFU/m3 in one study in an occupied patient room. Peaks in airborne contamination showed a direct relation to an increase in room activity. Monitoring found contamination levels to be lower overall during the night, and in unoccupied isolation rooms, with an average value of 20 CFU/m3. The highest counts were observed in an isolation room occupied for 10 days by a patient with C. difficile infection which generated an average microbial load of 104 CFU/m3 and a peak value of 510 CFU/m3. Discussion This study has demonstrated the degree of airborne contamination that can occur in the ICU environment over a 24 hour period. Numerous factors were found to contribute to the microbial air contamination levels, including patient status, length of room occupation, time of day and room activity, and further work is required to establish the extent to which this airborne bioburden contributes to cross-infection of patients

An economic survey of New Zealand wheatgrowers : survey no. 2

This is survey number 2. No. 1 was know as "National wheatgrowers' survey"This Report is the second in an annual series of economic surveys of New Zealand wheatgrowing farms. These surveys have been undertaken by the Agricultural Economics Research Unit at Lincoln College on behalf of Wheat Growers Sub-Section of Federated Farmers of New Zealand Inc. Specific attention has been focused on the physical characteristics of wheatgrowing farms, the area of wheat and other crops sown, wheat yields, cultural practices and costs and returns for the 1977/78 wheat crop. An attempt has also been made to allocate plant and machinery overhead costs to the wheat enterprise on both an historical and current cost basis. The need for current and detailed information from the Survey involved two visits to the farms in the sample; one in the spring following drilling and the second in the autumn after harvest

Population genetics of trypanosoma brucei rhodesiense: clonality and diversity within and between foci

African trypanosomes are unusual among pathogenic protozoa in that they can undergo their complete morphological life cycle in the tsetse fly vector with mating as a non-obligatory part of this development. Trypanosoma brucei rhodesiense, which infects humans and livestock in East and Southern Africa, has classically been described as a host-range variant of the non-human infective Trypanosoma brucei that occurs as stable clonal lineages. We have examined T. b. rhodesiense populations from East (Uganda) and Southern (Malawi) Africa using a panel of microsatellite markers, incorporating both spatial and temporal analyses. Our data demonstrate that Ugandan T. b. rhodesiense existed as clonal populations, with a small number of highly related genotypes and substantial linkage disequilibrium between pairs of loci. However, these populations were not stable as the dominant genotypes changed and the genetic diversity also reduced over time. Thus these populations do not conform to one of the criteria for strict clonality, namely stability of predominant genotypes over time, and our results show that, in a period in the mid 1990s, the previously predominant genotypes were not detected but were replaced by a novel clonal population with limited genetic relationship to the original population present between 1970 and 1990. In contrast, the Malawi T. b. rhodesiense population demonstrated significantly greater diversity and evidence for frequent genetic exchange. Therefore, the population genetics of T. b. rhodesiense is more complex than previously described. This has important implications for the spread of the single copy T. b. rhodesiense gene that allows human infectivity, and therefore the epidemiology of the human disease, as well as suggesting that these parasites represent an important organism to study the influence of optional recombination upon population genetic dynamics

ENVIRONMENTAL IMPACTS OF USING DESALINATED WATER IN CONCRETE PRODUCTION IN AREAS AFFECTED BY FRESHWATER SCARCITY

Up to 500 litres of water may be consumed at the batching plant per cubic meter of ready mix concrete, if water for washing mixing trucks and equipment is included. Demand for concrete is growing almost everywhere, regardless of local availability of freshwater. The use of freshwater for concrete production exacerbates stress on natural water resources. In water-stressed coastal countries such as Israel, desalinated seawater (DSW) is often used in the production of concrete. However, the environmental impacts of this practice have not yet been assessed. In this study the effect of using DSW on the water and carbon footprints of concrete was investigated using life cycle assessment. Water footprint results highlight the benefits of using DSW rather than freshwater to produce concrete in Israel. In contrast, because desalination is an energy intensive process, using DSW increases the greenhouse gas intensity of concrete. Nevertheless, this increase (0.27 kg CO2e/m3 concrete) is small, if compared to the life cycle greenhouse gas emissions of concrete. Our results show that using untreated seawater in the mix (transported by truck from the coast) in place of DSW, would be beneficial in terms of water and carbon footprints if the batching plant were located less than 13 km from the withdrawal point. However, use of untreated seawater increases steel reinforcement corrosion, resulting in loss of structural integrity of the reinforced concrete composite. Sustainability of replacing steel with non-corrosive materials should be explored as a way to reduce both water and carbon footprints of concrete

Increased aerobic capacity reduces susceptibility to acute high‐fat diet‐induced weight gain

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/134165/1/oby21564.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/134165/2/oby21564_am.pd

Immobilisation of platinum by Cupriavidus metallidurans

The metal resistant bacterium Cupriavidus metallidurans CH34, challenged with aqueous platinous and platinic chloride, rapidly immobilized platinum. XANES/EXAFS analysis of these reaction systems demonstrated that platinum binding shifted from chloride to carboxyl functional groups within the bacteria. Pt(IV) was more toxic than Pt(II), presumably due to the oxidative stress imparted by the platinic form. Platinum immobilisation increased with time and with increasing concentrations of platinum. From a bacterial perspective, intracellular platinum concentrations were two to three orders of magnitude greater than the fluid phase, and became saturated at almost molar concentrations in both reaction systems. TEM revealed that C. metallidurans was also able to precipitate nm-scale colloidal platinum, primarily along the cell envelope where energy generation/electron transport occurs. Cells enriched in platinum shed outer membrane vesicles that were enriched in metallic, colloidal platinum, likely representing an important detoxification strategy. The formation of organo-platinum compounds and membrane encapsulated nanophase platinum, supports a role for bacteria in the formation and transport of platinum in natural systems, forming dispersion halos important to metal exploration.Gordon Campbell, Lachlan MacLean, Frank Reith, Dale Brewe, Robert A. Gordon and Gordon Southa