Emerging new avian reovirus variants from cases of enteric disorders and arthritis/tenosynovitis in Brazilian poultry flocks.

1. The objective of this study was to characterise circulating Brazilian avian reovirus (ARV) strains by genetic analysis of the σC protein encoded by segment 1 of the viral genome and compare these with those of viral strains used for immunising commercial poultry.2. The analysis detected the presence of ARV genomes by quantitative reverse transcriptase PCR (RT-qPCR) in the enteric samples and the joint tissues (JT) of birds with signs of viral arthritis/tenosynovitis. Nucleotide sequencing used 16 strains (three commercial vaccines, 10 from enteric tissues and three from JT). The results indicated high variability in the amino acid sequences of 13 wild strains, showing between 40% and 75% similarity compared with the vaccine strains (S1133 and 2177).3. The sequences were grouped into three well-defined clusters in a phylogenetic tree, two of these clusters together with previous Brazilian σC ARV sequences, and one cluster (VII) that was novel for Brazilian strains. Antigenic analysis showed that there were amino acids within putative epitopes located on the surface of the receptor-binding region of the σC protein with a high degree of variability.4. The study confirmed the presence of ARV genetic variants circulating in commercial birds in Brazil, and according to the antigenic prediction, the possibility of antigenic variants appears to be high.

Comparison of different stomatal conductance algorithms for ozone flux modelling.

A multiplicative and a semi-mechanistic, BWB-type [Ball, J.T., Woodrow, I.E., Berry, J.A., 1987. A model predicting stomatal conductance and its contribution to the control of photosynthesis under different environmental conditions. In: Biggens, J. (Ed.), Progress in Photosynthesis Research, vol. IV. Martinus Nijhoff, Dordrecht, pp. 221-224.] algorithm for calculating stomatal conductance (g(s)) at the leaf level have been parameterised for two crop and two tree species to test their use in regional scale ozone deposition modelling. The algorithms were tested against measured, site-specific data for durum wheat, grapevine, beech and birch of different European provenances. A direct comparison of both algorithms showed a similar performance in predicting hourly means and daily time-courses of g(s), whereas the multiplicative algorithm outperformed the BWB-type algorithm in modelling seasonal time-courses due to the inclusion of a phenology function. The re-parameterisation of the algorithms for local conditions in order to validate ozone deposition modelling on a European scale reveals the higher input requirements of the BWB-type algorithm as compared to the multiplicative algorithm because of the need of the former to model net photosynthesis (A(n)).

Growth response to ozone of annual species from Mediterranean pastures.

Ozone (O3) phytotoxicity has been reported on a wide range of plant species. However, scarce information has been provided regarding the sensitivity of semi-natural grassland species, especially those from dehesa Mediterranean grasslands, in spite of their great biological diversity and the high O3 levels recorded in the region. A screening study was carried out in open-top chambers (OTCs) to assess the O3-sensitivity of representative therophytes of these ecosystems based on the response of selected growth-related parameters. Three O3 treatments and 3 OTCs per treatment were used. Legume species were very sensitive to O3, because 78% of the tested species showed detrimental effects on their total biomass relative growth rate (RGR) following their exposure to O3. The Trifolium genus was particularly sensitive showing O3-induced adverse effects on most of the assessed parameters. Gramineae plants were less sensitive than Leguminosae species because detrimental effects on total biomass RGR were only observed in 14% of the assessed species. No relationship was found between relative growth rates when growing in clean air and O3 susceptibility. The implications of these effects on the performance of dehesa acidic grasslands and on the definition of ozone critical levels for the protection of semi-natural vegetation are discussed.

Síndrome de Peutz Jeghers

Se presenta el caso de un hombre joven son Síndrome de Peutz Jeghers quien presentó hemorragia digestiva alta manejada endoscópicamente e intusucepción intestinal que requirió manejo quirúrgico. Se revisa el tema

Pólipos gástricos. Revisión de 5 años Hospital General Universitario de La Samaritana

Presentamos en esta revisión la prevalencia de los pólipos gástricos en la Unidad de Gastroenterología y Endoscopia Digestiva del Hospital General Universitario la Samaritana (HGUS). Se analizaron las características de los mismos y los hallazgos histológicos, al igual que su manejo

Placebo-controlled study of lisinopril in congestive heart failure: a multicentre study.

A double-blind randomised, parallel, placebo-controlled study was performed in patients with congestive heart failure, at 13 centres in 10 countries, to assess the efficacy and safety of lisinopril, a new angiotensin-converting enzyme inhibitor. After a 2-week run-in period, 130 patients receiving digoxin and/or diuretics were randomised to 12 weeks of treatment with lisinopril 5 mg daily (87 patients) or with placebo (43 patients), with an option to increase lisinopril dosage to 10 or 20 mg. Patients treated with lisinopril improved significantly more than placebo-treated patients (p less than 0.05) for all clinical parameters except oedema and paroxysmal nocturnal dyspnoea. Left ventricular ejection fraction rose by 8% in lisinopril patients compared to 2% in the placebo group, while the cardiothoracic ratio and echocardiographic end systolic diameter fell in the lisinopril group (p less than 0.01) but not in the placebo group. Exercise duration was greater in the lisinopril group at all timepoints, and the increase in exercise duration at 12 weeks was greater by more than 2 min in the lisinopril group as compared to the placebo group (p less than 0.01). Changes in clinical and noninvasive parameters such as the New York Heart Association status, were well correlated with changes in exercise duration. Four patients in the lisinopril group and three in the placebo group died in this study, and there were 31 adverse clinical experiences in the 87 lisinopril-treated patients compared to 13 in the 43 placebo-treated patients. We conclude that lisinopril in doses of 2.5-20 mg/day is well tolerated and effective in patients with heart failure who are receiving digitalis and diuretics.

Biological populations obeying difference equations: the effects of stochastic perturbation.

We consider the effects of stochastic perturbation in various components of a finite difference model arising in population biology. In particular, we examine how fluctuation in the net reproductive rate can effect the population dynamics of the system. Computer simulation and some elementary analyses bear out the result that, in the mean, the stochastic dynamics will behave like the deterministic dynamics. This study also answers a currently unanswered conjecture published by the first author in 1977.