Using molecular data for epidemiological inference: assessing the prevalence of Trypanosoma brucei rhodesiense in Tsetse in Serengeti, Tanzania

Background: Measuring the prevalence of transmissible Trypanosoma brucei rhodesiense in tsetse populations is essential for understanding transmission dynamics, assessing human disease risk and monitoring spatio-temporal trends and the impact of control interventions. Although an important epidemiological variable, identifying flies which carry transmissible infections is difficult, with challenges including low prevalence, presence of other trypanosome species in the same fly, and concurrent detection of immature non-transmissible infections. Diagnostic tests to measure the prevalence of T. b. rhodesiense in tsetse are applied and interpreted inconsistently, and discrepancies between studies suggest this value is not consistently estimated even to within an order of magnitude. Methodology/Principal Findings: Three approaches were used to estimate the prevalence of transmissible Trypanosoma brucei s.l. and T. b. rhodesiense in Glossina swynnertoni and G. pallidipes in Serengeti National Park, Tanzania: (i) dissection/microscopy; (ii) PCR on infected tsetse midguts; and (iii) inference from a mathematical model. Using dissection/microscopy the prevalence of transmissible T. brucei s.l. was 0% (95% CI 0–0.085) for G. swynnertoni and 0% (0–0.18) G. pallidipes; using PCR the prevalence of transmissible T. b. rhodesiense was 0.010% (0–0.054) and 0.0089% (0–0.059) respectively, and by model inference 0.0064% and 0.00085% respectively. Conclusions/Significance: The zero prevalence result by dissection/microscopy (likely really greater than zero given the results of other approaches) is not unusual by this technique, often ascribed to poor sensitivity. The application of additional techniques confirmed the very low prevalence of T. brucei suggesting the zero prevalence result was attributable to insufficient sample size (despite examination of 6000 tsetse). Given the prohibitively high sample sizes required to obtain meaningful results by dissection/microscopy, PCR-based approaches offer the current best option for assessing trypanosome prevalence in tsetse but inconsistencies in relating PCR results to transmissibility highlight the need for a consensus approach to generate meaningful and comparable data

Transmembrane helix dynamics of bacterial chemoreceptors supports a piston model of signalling.

Transmembrane α-helices play a key role in many receptors, transmitting a signal from one side to the other of the lipid bilayer membrane. Bacterial chemoreceptors are one of the best studied such systems, with a wealth of biophysical and mutational data indicating a key role for the TM2 helix in signalling. In particular, aromatic (Trp and Tyr) and basic (Arg) residues help to lock α-helices into a membrane. Mutants in TM2 of E. coli Tar and related chemoreceptors involving these residues implicate changes in helix location and/or orientation in signalling. We have investigated the detailed structural basis of this via high throughput coarse-grained molecular dynamics (CG-MD) of Tar TM2 and its mutants in lipid bilayers. We focus on the position (shift) and orientation (tilt, rotation) of TM2 relative to the bilayer and how these are perturbed in mutants relative to the wildtype. The simulations reveal a clear correlation between small (ca. 1.5 Å) shift in position of TM2 along the bilayer normal and downstream changes in signalling activity. Weaker correlations are seen with helix tilt, and little/none between signalling and helix twist. This analysis of relatively subtle changes was only possible because the high throughput simulation method allowed us to run large (n = 100) ensembles for substantial numbers of different helix sequences, amounting to ca. 2000 simulations in total. Overall, this analysis supports a swinging-piston model of transmembrane signalling by Tar and related chemoreceptors

Changes in Seizure Frequency and Test-Retest Scores on the Wechsler Adult Intelligence Scale

Test-retest performance on the Wechsler Adult Intelligence Scale (WAIS) of two groups of adult epilepsy patients are presented and compared. In one group, Seizures Improved (SI) group, seizure frequency had decreased during the test-retest interval, and in the other group, Seizures Unimproved (SU) group, the number of seizures had either increased or stayed the same over the test-retest interval. The SI group showed a significant test-retest improvement on WAIS Verbal IQ, Performance 1Q, and Full Scale IQ, as well as on eight of 11 WAIS subtests. In comparison, the SU group showed significant increases only on the Performance IQ and Object Assembly subtest. Furthermore, differences between the two groups were observed in the pattern of test-retest changes seen on the Performance measures relative to the Verbal measures. The results suggest that change in seizure frequency is one of the factors associated with test-retest changes in the intellectual functioning of epilepsy patients. RÉSUMÉ Les rÉsultats obtenus À I‘Échelle de WAIS (Wechsler Adults Intelligence Scale) a partir d'une passation I (test) et d'une passation II (retest) chez deux groupes d'Épileptiques adultes sont prÉsentÉs et compares: (a) Dans un groupe la frequence des crises a diminue dur-ant I'intervalle “test-retest” (c'est a dire dans I'inter-valle separant la passation I (test) de la passation II (retest): Groupe des crises ameliorees (SI: seizures improved), (b) Dans l'autre groupe le nombre des crises au contraire a augmente ou bien est reste iden-tique au cours de I'intervalle “test-retest”: Groupe des crises non ameliorees (SU: seizures unimproved). Le groupe des “crises ameliorees” montre une amelioration significative tant sur le plan du QIV (quotient de I'echelle verbale), que du QIP (quotient de I'echelle performance) et du QIG (quotient global), ainsi que de 8 des subtests parmi les onze que contien I'echelle. En comparaison le groupe des “crises non ameliorees” ne montre une amelioration significative qu'au niveau du QIP et en particulier sur le subtest d'assemblage d'ob-jets (celui-ci faisant partie de I'echelle performance). De plus, on observe entre les deux groupes des differences du “type” des modifications entrainees par la situation “test-retest”, sur les rÉsultats obtenus a I'echelle performance et ceux obtensus a I'echelle verbale. Ces rÉsultats permettent de suggerer que, dans le fonctionnement intellectuel des sujets epileptiques, les changements dans la frequence des crises sont un des facteurs a mettre en correlation avec les changements observes a partir de la situation “test-retest”. RESUMEN Se compararon dos grupos de adultos con epilepsia por medio del rendimiento en dos tests de WAIS. En un grupo, la frecuencia de los ataques habia disminuido en el intervalo entre el primer test y el segundo [grupo con mejoria (SI)], mientras que en el otro el mimero de crisis no habia variado o habia au-mentado [grupo sin mejoria (SU)]. El grupo SI mostro una mejoria en laescala verbal CI, en la realizacion CI, en la escala total de CI y en los subtests WAIS. En comparacion, el grupo SU solo mostro un aumento significativo en la realizacion CI y en el subtest de Reunion de Objetos. Ademas, se observaron diferen-cias entre los dos grupos en lo que respecta a la prim-era y a la segunda prueba en la realizacion de las medidas verbales. Los resultados sugieren que los cambios en la frecuencia de los ataques juegan un papel en lo que respecta a funciÓn intelectual cuando se compara el primer WAIS con el segundo. ZUSAMMENFASSUNG Test und Retest Ergebnisse im WAIS von 2 Gruppen erwachsener Epileptiker werden dargestellt und ver-glichen. In einer Gruppe hatte die Anfallshaufigkeit wahrend des Test-Retest-Intervalls abgenommen– verbesserte Gruppe (SI)–und in einer anderen Gruppe war die Anfallshaufigkeit entweder gestiegen oder gleich geblieben wahrend des Test-Retest-Intervalls– unveranderte Gruppe (SU). Die SI-Gruppe zeigte signifikante Verbesserung zwischen Test und Retest im Verbal-IQ des WAIS, im Handlungsteil und im Gesamt-IQ ebenso wie in 8 von 11 WAIS Subtests. Im Vergleich hierzu zeigte die SU-Gruppe signifikante Verbesserung nur im Handlungs-IQ und im Objekte-zuordnungs-Subtest. Weiterhin wurden Unterschiede zwischen den beiden Gruppen im Muster der Test-Retest-Veranderungen im Verhaltnis des Handlung-steils zum Verbalteil bemerkt. Die Ergebnisse lassen vermuten, dalJ die Veranderung der Anfallshaufigkeit einer der Faktoren ist, der hinsichtlich der in-tellektuellen Funktion anfallskranker Patienten Bezie-hungen zu den Veranderungen des Test-Retest-Ergeb-nis aufweist.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65457/1/j.1528-1157.1981.tb04334.x.pd

Does Al4H14— cluster anion exist? High-level ab initio study

A comprehensive ab initio investigation using coupled cluster theory with the aug-cc-pVnZ, n = D,T basis sets is carried out to identify distinct structures of the Al4H14— cluster anion and to evaluate its fragmentation stability. Both thermodynamic and mechanistic aspects of the fragmentation reactions are studied. The observation of this so far the most hydrogenated aluminum tetramer was reported in the recent mass spectrometry study of Li et al. (2010) J Chem Phys 132:241103–241104. The four Al4H14— anion structures found are chain-like with the multiple-coordinate Al center and can be viewed approximately as comprising Al2H7— and Al2H7 moieties. Locating computationally some of the Al4H14— minima on the correlated ab initio potential energy surfaces required the triple-zeta quality basis set to describe adequately the Al multi-coordinate bonding. For the two most stable Al4H14— isomers, the mechanism of their low-barrier interconversion is described. The dissociation of Al4H14— into the Al2H7— and Al2H7 units is predicted to require 20-22 (10-13) kcal mol-1 in terms of ΔH (ΔG) estimated at T = 298.15 K and p = 1 atm. However, Al4H14— is found to be a metastable species in the gas phase: the H2 loss from the radical moiety of its most favorable isomer is exothermic by 18 kcal mol-1 in terms of ΔH (298.15 K) and by 25 kcal mol-1 in terms of ΔG(298.15 K), with the enthalpic/free energy barrier involved being less than 1 kcal mol-1. By contrast with alane Al4H14—, only a weakly bound complex between Ga4H12— and H2 has been identified for the gallium analogue using the relativistic effective core potential

Decision making in interhospital transport of critically ill patients: national questionnaire survey among critical care physicians

Objective: This study assessed the relative importance of clinical and transport-related factors in physicians' decision-making regarding the interhospital transport of critically ill patients. Methods: The medical heads of all 95 ICUs in The Netherlands were surveyed with a questionnaire using 16 case vignettes to evaluate preferences for transportability; 78 physicians (82%) participated. The vignettes varied in eight factors with regard to severity of illness and transport conditions. Their relative weights were calculated for each level of the factors by conjoint analysis and expressed in beta. The reference value (beta = 0) was defined as the optimal conditions for critical care transport; a negative beta indicated preference against transportability. Results: The type of escorting personnel (paramedic only: beta = 3.1) and transport facilities (standard ambulance beta = 1.21) had the greatest negative effect on preference for transportability. Determinants reflecting severity of illness were of relative minor importance (dose of noradrenaline beta = 0.6, arterial oxygenation beta = 0.8, level of peep beta = 0.6). Age, cardiac arrhythmia, and the indication for transport had no significant effect. Conclusions: Escorting personnel and transport facilities in interhospital transport were considered as most important by intensive care physicians in determining transportability. When these factors are optimal, even severely critically ill patients are considered able to undergo transport. Further clinical research should tailor transport conditions to optimize the use of expensive resources in those inevitable road trip

Strong expression of TGF-beta in human host tissues around subcutaneous Dirofilaria repens

Dirofilaria repens and other Dirofilaria species are widely distributed parasitic nematodes of carnivores, which occasionally are transmitted to men, causing subcutaneous nodules. In humans, it usually occurs only as single male or female filariae without production of microfilariae. The non-productive living or dead Dirofilaria worms in subcutaneous biopsies from 15 human patients permitted us to study the role of the pleiotropic and immunoregulatory cytokine transforming growth factor beta (TGF-beta) independent from the influence of microfilariae. Antiserum against latent TGF-beta 1 was used for an immunohistological examination. In the infiltrates around female and male filariae, there occurred strongly TGF-beta-positive macrophages, mast cells, endothelial cells, fibrocytes, and giant cells adjacent to dead worms. In one nodule, secondary lymph follicles were observed with clearly TGF-beta-positive B cells in the mantle zone and weakly positive macrophages and B cells in the germinal centre. A network of CD35-positive follicular dendritic cells was observed in the germinal centre. All Dirofilaria contained Wolbachia endobacteria, which probably had attracted the numerous TGF-beta-negative neutrophils near to the worm. Wolbachia were phagocytosed by neutrophils adjacent to dead filariae. Macrophages and lymphocytes expressed the MHC class II molecule HLA-DR in small accumulations of immune cells in the outer zone of the infiltrate and the mantle zone and germinal centre of secondary lymph follicles. It is concluded that single non-productive Dirofilaria worms elicit a strong expression of TGF-beta. This result is in accordance with observations on Onchocerca volvulus from patients with the hyporeactive (generalised) form

Study of the reaction e^{+}e^{-} -->J/psi\pi^{+}\pi^{-} via initial-state radiation at BaBar

We study the process $e^+e^-\to J/\psi\pi^{+}\pi^{-}$ with initial-state-radiation events produced at the PEP-II asymmetric-energy collider. The data were recorded with the BaBar detector at center-of-mass energies 10.58 and 10.54 GeV, and correspond to an integrated luminosity of 454 $\mathrm{fb^{-1}}$. We investigate the $J/\psi \pi^{+}\pi^{-}$ mass distribution in the region from 3.5 to 5.5 $\mathrm{GeV/c^{2}}$. Below 3.7 $\mathrm{GeV/c^{2}}$ the $\psi(2S)$ signal dominates, and above 4 $\mathrm{GeV/c^{2}}$ there is a significant peak due to the Y(4260). A fit to the data in the range 3.74 -- 5.50 $\mathrm{GeV/c^{2}}$ yields a mass value $4244 \pm 5$ (stat) $\pm 4$ (syst)$\mathrm{MeV/c^{2}}$ and a width value $114 ^{+16}_{-15}$ (stat)$\pm 7$(syst)$\mathrm{MeV}$ for this state. We do not confirm the report from the Belle collaboration of a broad structure at 4.01 $\mathrm{GeV/c^{2}}$. In addition, we investigate the $\pi^{+}\pi^{-}$ system which results from Y(4260) decay

Genetic diversity and structure of Iberian Peninsula cowpeas compared to world-wide cowpea accessions using high density SNP markers

Cowpea (Vigna unguiculata L. Walp) is an important legume crop due to its high protein content, adaptation to heat and drought and capacity to fix nitrogen. Europe has a deficit of cowpea production. Knowledge of genetic diversity among cowpea landraces is important for the preservation of local varieties and is the basis to obtain improved varieties. The aims of this study were to explore diversity and the genetic structure of a set of Iberian Peninsula cowpea accessions in comparison to a worldwide collection and to infer possible dispersion routes of cultivated cowpea.This study was supported by EUROLEGUME project. This project has received funding from the European Union’s Seventh Framework Programme for research, technological development and demonstration under grant agreement no 613781. European Investment Funds by FEDER/COMPETE/ POCI – Operational Competitiveness and Internationalization Programme, under Project POCI-01-0145-FEDER-006958 and National Funds by FCT – Portuguese Foundation for Science and Technology, under the project UID/AGR/04033/2013. MMA was partially supported by the Feed the Future Innovation Lab for Climate Resilient Cowpea (USAID Cooperative Agreement AID-OAA-A-13-00070), which is directed by TJC. The funding entities had no role in the design of the study, collection, analysis and interpretation of data, or in writing the manuscript.info:eu-repo/semantics/publishedVersio