Investigations of Phlebotomus perniciosus sand flies in rural Spain reveal strongly aggregated and gender-specific spatial distributions and advocate use of light-attraction traps

The spatial and temporal distribution of Phlebotomus perniciosus (Diptera: Psychodidae) (Newstead, 1911), the sand fly vector of pathogens of public and animal health importance, was investigated in a high sand fly density rural area in Spain using light-attraction and sticky-interception traps. Traps were placed inside animal buildings and outside at increasing distance from animals. A total of 8506 sand flies were collected, 87% with light traps. Species frequency differed between trap types. The abundance of P. perniciosus decreased exponentially with increasing distance to animals and, while females were most common in the animal enclosure, males predominated in adjoining storage places. Increasing CO₂ concentration had an additional positive effect on female abundance only. Both male and female density increased with rising temperature, and there was some indication that females were more active than males at higher relative humidity. The study confirms that P. perniciosus aggregates around animal premises, although male and female distributions differ and should be analysed separately to account for biological and behavioural differences. This provides further evidence that light traps offer an accurate estimation of the relative spatial and temporal abundance of P. perniciosus, conferring an added value for the study of this species and the risk of pathogen transmission.

Epidemiological and genetic studies suggest a common Leishmania infantum transmission cycle in wildlife, dogs and humans associated to vector abundance in Southeast Spain

Leishmania infantum infection was investigated in 202 wild carnivores, rodents and lagomorphs in Southeast Spain using a real-time PCR (rtPCR) in skin and organ samples, mostly spleen. Lesions compatible with leishmaniosis were not observed in any of the animals. Prevalence defined as the percentage of rtPCR-positive animals was 32% overall, and 45% in foxes (n = 69), 30% in rabbits (n = 80) and stone martens (n = 10), 19% in wood mice (n = 16), 0% in black rats (n = 10) and ranged between 0% and 100% in other minoritarian species including badgers, wild cats, wolves, raccoons, genets and hares. Most infected rabbits were rtPCR-positive in skin and not in spleen samples and the opposite was the case for foxes (p < 0.05). L. infantum prevalence was lowest in spring following months of non-exposure to phlebotomine sand fly vectors, and spatially matched recently estimated Phlebotomus perniciosus vector abundance and the prevalence of subclinical infection in dogs and humans. Prevalence increased with altitude and was greater in drier and less windy South and West compared to the coastal Southeast of the study area (p < 0.05). Genetic diversity of L. infantum from foxes, investigated by PCR-restriction fragment length polymorphisms of kinetoplast DNA, revealed B genotype in all animals, which is frequent in people and dogs in the Iberian Peninsula and Morocco. The study provides further evidence that subclinical L. infantum infection is widespread in wildlife with prevalence depending on environmental factors and that parasite tissue tropism may vary according to host species. Moreover, it suggests that sylvatic and domestic transmission cycles are closely interconnected.

Association between preterm birth and its subtypes and maternal sociodemographic characteristics during the post-transitional phase in a developing country with a very high human development index

OBJECTIVES

Chile is a post-transitional country evolving towards a stationary population pyramid, which may be associated with increasing preterm birth (PTB) rates. This study aimed to compare maternal sociodemographic characteristics between the start of the post-transition phase (1994) and an established stage (2013) and to evaluate associations between these characteristics and PTB.

STUDY DESIGN

An observational analytic design was conducted using national birth records (n = 4,956,311).

METHODS

Variables analysed in the 20 birth cohorts from 1994 to 2013 were: length of gestation (preterm <37 weeks) subdivided by gestational age (extreme, moderate/severe and late); maternal age (≤19, 20-35 and >35 years); education level (<8, 8-12 and >12 years of education); employment; marital status; area of residence; and type of birth (singleton, twins, and triplets or higher order). The prevalence of PTB was expressed as a percentage, and associations between PTB and predictor variables were analysed using logistic regression models.

RESULTS

Education level, age >35 years, maternal employment, unmarried status, twin delivery and urban residency rates increased between 1994 and 2013. According to the adjusted models, age >35 years and delivery of more than two foetuses were risk factors for all PTB subtypes. Maternal employment was a risk factor for moderate/severe, late and total PTB, and a low level of education was a risk factor for late and total PTB. On the other hand, age ≤19 years was protective against all PTB subtypes.

CONCLUSIONS

All maternal characteristics changed between 1994 and 2013. Furthermore, the prevalence of PTB increased for all predictor variables studied over this period.

Datos morfométricos de Trypanosoma evansi en carpinchos (Hydrochaeris hydrochaeris) de Chaco, Argentina

El objetivo del trabajo fue verificar la existencia de variaciones morfométricas de Trypanosoma evansi en Hydrochaeris hydrochaeris criados en cautiverio en Chaco, Argentina. Para ello se efectuaron mediciones de variables biométricas de 52 ejemplares de T. evansi provenientes de carpinchos. Se reconocieron dos variaciones morfométricas del parásito, delgadas y rechonchas. Las dimensiones de ambas formas se compararon con los resultados obtenidos en T. evansi de carpinchos del amazonas peruano. Los resultados revelaron diferencias significativas en todas las variables sometidas a estudio (p&lt;0,05). Se concluye que al parasitar a H. hydrochaeris, T. evansi presenta dimensiones morfométricas diferentes a las halladas en Perú, variando inclusive en el mismo animal.

Use of serum levels of high sensitivity troponin T, galectin-3 and C-terminal propeptide of type I procollagen at long term follow-up in heart failure patients with reduced ejection fraction: Comparison with soluble AXL and BNP

BACKGROUND

Prognostic biomarkers are needed to improve the management of the heart failure (HF) epidemic, being the brain natriuretic peptides the most valuable. Here we evaluate 3 biomarkers, high sensitivity troponin T (hs-TnT), galectin-3 (Gal-3) and C-terminal propeptide of type I procollagen (CICP), compare them with a recently described new candidate (sAXL), and analyze their relationship with BNP.

METHODS

HF patients with reduced ejection fraction (n=192) were included in this prospective observational study, with measurements of candidate biomarkers, functional, clinical and echocardiographic variables. A Cox regression model was used to determine predictors for clinical events, i.e. all-cause mortality and heart transplantation.

RESULTS

Hs-TnT circulating values were correlated to clinical characteristics indicative of more advanced HF. When analyzing the event-free survival at a mean follow-up of 3.6years, patients in the higher quartile of either BNP, hs-TnT, CICP and sAXL had increased risk of suffering a clinical event, but not Gal-3. Combination of high sAXL and BNP values had greater predictive value (HR 6.8) than high BNP alone (HR 4.9). In a multivariate Cox regression analysis, BNP, sAXL and NYHA class were independent risk factors for clinical events.

CONCLUSIONS

In this HF cohort, hs-TnT is a good HF marker and has a very significant prognostic value. The prognostic value of CICP and sAXL was of less significance. However, hs-TnT did not add predictive value to BNP, while sAXL did. This suggests that elevated troponin has a common origin with BNP, while sAXL could represent an independent pathological mechanism.

Data on clinical characteristics of a heart failure patients' cohort with reduced ejection fraction and analysis of the circulating values of five different heart failure biomarkers; high sensitivity troponin T, galectin-3, C-terminal propeptide of type I procollagen, soluble AXL and BNP

In this article, the full description of a heart failure with reduced ejection fraction (HF_REF) cohort of 192 patients is provided. Tables with the baseline demographic, prior history, ECG parameters, echocardiographic parameters, laboratory values and pharmacological treatment of these patients are included. Also, the quartile values of the analyzed circulating biomarkers: high sensitivity Troponin T (hs-TnT), galectin-3 (Gal-3), C-terminal propeptide of type I procollagen (CICP), soluble AXL (sAXL) and Brain Natriuretic Peptide (BNP) are given. The main demographic and clinical features of the patients’ subgroups that have hs-TnT, Gal-3, CICP or BNP above the third quartile are described. Tables with Pearson correlation analysis of the HF_REF patients’ biomarker levels are included. And Pearson correlation analysis of the HF_REF patients’ hs-TnT, Gal-3, CICP levels with patients’ biochemical parameters, blood count and inflammation parameters are also described. These data are related to the research articles (AXL receptor tyrosine kinase is increased in patients with heart failure (M. Batlle, P. Recarte-Pelz, E. Roig, M.A. Castel, M. Cardona, M. Farrero, et al., 2014) [1] and Use of serum levels of high sensitivity troponin T, galectin-3 and C-terminal propeptide of type I procollagen at long term follow-up in Heart Failure patients with reduced ejection fraction: comparison with soluble AXL and BNP (M. Batlle, B. Campos, M. Farrero, M. Cardona, B. González, M.A. Castel, et al., 2016) [2].

Nota. Efecto de la historia térmica en la gelificación de pasta fresca de jurel (T. murphyi) tipo surimi Note. Effect of thermal history on the gelation of horse mackerel (T. murphyi) raw paste surimi-type

Fresh paste from horse mackerel ( T. murphyi) surimi-type, was processed during setting using (2%) KCI. The paste was subjected to different heating and cooling cycles. The salt produced an improve ment in kamaboko-type gel formation. The heating and cooling cycles enhanced the setting process and improved textural quality of the resulting gel, mainly when the heating before cooling was slow. The setting process was characterized by several physical parameters: storage module ( G'), using an oscillatory rheological technique, and apparent Young module ( E), by means of mechanical compres sion tests. The enthalpic changes for gelification of the paste were determined using differential scan ning calorimetry.

Effect of Kappa-Carrageenan on the Gelation of Horse Mackerel (T. Murphyi) Raw Paste Surimi-Type

Gelation of fresh (unfrozen) raw surimi-type paste (RS paste) from horse mackerel ( T. murphyi) was studied in the presence of-carrageenan (0.5, 1, 2% C) and KCl (0.5-2%) as a substitute for NaCl. Gelation was traced by measuring the storage modulus (G) during heating-cooling cycles. Variations in G during the heating stage of the mixed system RS-C characterised the presence of a phase separation in this stage due to C solubilitation (at about 50°C) as well as to RS gelation (35-80°C) in the mixture. It was also observed that when C was added as a single ingredient, it inhibited RS gelation as a function of its concentration (2%). Nevertheless, during the cooling stage, the final G value for the RS-2% C mixed system was greatly increased. This reinforcing would be caused by further (cold) C gelation in the mixture. It is theorised that C might act by forming ‘packed’ microgels within the RS protein gel network, which is favoured upon application of a moderate (40°C, 60min) thermal treatment rather than when an extreme (90°C, 20min) treatment is applied. On the other hand, although KCl enhanced gelation of the 2% C solution, addition of this salt to the RS-2% C mixture did not improve its gelation. Rheological information was complemented with observation of the resulting structures by scanning electronic microscopy (SEM).

Calculation of Coincidence Summing Correction Factors for an HPGe detector using GEANT4

The aim of this paper was to calculate the True Coincidence Summing Correction Factors (TSCFs) for an HPGe coaxial detector in order to correct the summing effect as a result of the presence of (88)Y and (60)Co in a multigamma source used to obtain a calibration efficiency curve. Results were obtained for three volumetric sources using the Monte Carlo toolkit, GEANT4. The first part of this paper deals with modeling the detector in order to obtain a simulated full energy peak efficiency curve. A quantitative comparison between the measured and simulated values was made across the entire energy range under study. The True Summing Correction Factors were calculated for (88)Y and (60)Co using the full peak efficiencies obtained with GEANT4. This methodology was subsequently applied to (134)Cs, and presented a complex decay scheme.