Temporal fluctuation of infection with different Trypanosoma cruzi genotypes in the wild rodent Octodon degus

We identified and followed-up for two years Octodon degus rodents infected with Trypanosoma cruzi genotypes by using xenodiagnosis with two vector species (Mepraia spinolai and Triatoma infestans), polymerase chain reaction DNA-based detection of insect dejections, Southern blot analysis, and minicircle hybridization with genotype-specific probes. Results show temporal fluctuations of infection with four parasite lineages (TCI, TCII, TCV, and TCVI) in one co-infected O. degus. Results are discussed in the context of parasitemia level and infection control in mammal hosts.

European rabbits (Oryctolagus cuniculus) are naturally infected with different Trypanosoma cruzi genotypes

Trypanosoma cruzi, the etiologic agent of Chagas disease, presents a complex life cycle, cycling between reduviid vectors and wild and domestic mammals. The European rabbit is an introduced species in America, but its role as reservoir in the wild transmission cycle of Chagas disease remains unknown. We used polymerase chain reaction, Southern blot, and hybridization tests to detect infection and characterize genotypes in rabbits from a hyperendemic area of Chagas disease in Chile. Results show 38% of infection with different genotypes. We provide evidence that rabbits are naturally infected with T. cruzi, which may have important epidemiologic consequences for the wild transmission cycle.

[A pilot study on a quality improvement plan with systematic nutritional screening in patients admitted to a regional hospital]

OBJECTIVE

A pilot study to assess the feasibility of implementing a hospital protocol for systematic nutritional screening of admitted patients.

METHOD

Descriptive cross-sectional study. Patients admitted to the Orthopedic Surgery Department of the Regional Hospital of Alcañiz were systematically included within the first 48 hours of hospitalization, from February to September of 2007. The screening methods used were the Nutritional Risk Index (NRI), the CONUT Nutritional Control system, and an indicator based on SENPE recommendations. The need for nutritional support was defined as the presence of any of the following instances: moderate to severe hyponutrition according to the NRI or CONUT methods, or hyponutrition according to the adapted SENPE recommendations.

RESULTS

36.4% of the patients assessed need nutritional support. The rate of hyponutrition according to CONUT is 13.6%, by SENPE criteria is 27.3%, and by the NRI 29.5%. The inter-method agreement is statistically significant and clinically acceptable: Kappa between NRI and CONUT 0.547, between NRI and SENPE 0.609, and between CONUT and SENPE 0.593.

CONCLUSIONS

The implementation of a structured protocol for collecting the anthropometrical and biochemical parameters implicating a multidisciplinary hospital team enables identifying those patients in whom appropriate nutritional support may improve their prognosis during hospital stay.

Systematization and distribution of the middle cerebral artery on the brain surface in pampas fox (Pseudalopex gymnocercus)

The present study has analysed 30 pampas fox brains (Pseudalopex gymnocercus), injected with latex, aiming to systematize and describe the distribution and vascularization territories of the middle cerebral artery. After being originated from the rostral branch of the internal carotid artery this vessel formed the following collateral branches: rostral choroidal artery, rostral and caudal central branches and cortical branches. Before crossing the lateral rhinal sulcus, the common trunk of the middle cerebral artery frequently bifurcated in a rostral and a caudal branch. In a smaller amount, the common trunk did not show any bifurcation, ramifying in arborescence. The vascular territory of the pampas fox middle cerebral artery included the lateral cerebral fossa, the lateral third of the olfactory trigone, the two rostral thirds of the piriform lobe, the lateral olfactory tract and most of the convex surface of the cerebral hemisphere, except for the more rostromedial areas of the frontal lobe bordering the endomarginal sulcus in the parietal and occipital lobes as well as the transverse fissure at the caudal pole of the cerebral hemisphere.

Susceptibility of Mepraia spinolai and Triatoma infestans to different Trypanosoma cruzi strains from naturally infected rodent hosts

Trypanosoma cruzi is the causative agent of Chagas disease, a zoonosis involving domestic and sylvatic mammalian reservoirs. Since scarce information has been published about the susceptibility of T. cruzi lineages to other triatomine species besides Triatoma infestans, we evaluate the susceptibility of T. infestans and Mepraia spinolai to different T. cruzi lineages, originated from naturally infected Octodon degus rodents as mammal host. Xenodiagnosis-PCR methods to detect T. cruzi positive rodents and genotyping to differentiate T. cruzi lineages (TcI, TcIIb, TcIId and TcIIe) identified singly and mixed T. cruzi infections. More infections and nearly all mixed infections were identified using the wild vector M. spinolai than T. infestans.