New cholinesterase inhibiting bisbenzylisoquinoline alkaloids from Abuta grandifolia

The phytochemical study of the stem bark and wood of Abuta grandifolia (Mart.) Sandwith led to the identification of four bisbenzylisoquinoline alkaloids (BBIQs), namely (R,S)-2 N-norberbamunine (1), (R,R)-isochondodendrine (2), (S-S)-O4″-methyl, Nb-nor-O6'-demethyl-(+)-curine (3), and (S-S)-O4″-methyl, O6'-demethyl-(+)-curine (4), together with the aporphine alkaloid R-nornuciferine (5), all obtained by countercurrent distribution separation (CCD) and identified on the basis of their spectroscopic data. Alkaloids 3 and 4 were new. All the isolated compounds were tested for acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activities. 1 was the most active against AChE, whereas 3 and 4 were the most potent against BChE. Interestingly, all tested alkaloids are more potent against BChE than against AChE. This selectivity of cholinesterase (ChE) inhibition could be important in order to speculate on their potential therapeutic relevance.     

Identification of virulence factors by multiplex PCR in Escherichia coli isolated from calves in Minas Gerais, Brazil

In this study, multiplex PCR was employed to investigate the virulence factors of Escherichia coli strains isolated from 60-day-old calves. Faecal samples were collected from 54 calves at 12 dairy farms in the state of Minas Gerais, Brazil. A total of 156 isolates were obtained after culture and microbiological isolation and were tested by multiplex PCR for the presence of genes encoding toxins (Stx1, Stx2 and STa) and adherence factors (intimin, F41 and F5). Seventy of 156 isolates were positive for at least one virulence factor: ten (14.3?%) from diarrhoeic animals and 60 (85.7?%) from healthy calves. The virulence markers identified were: Stx1 (82.8?%), eae (24.3?%), F41 (11.4?%), F5 (10?%), STa (4.28?%) and Stx2 (4?%). In diarrhoeic animals, Stx1 (70?%) and F41 (30?%) were identified, while Stx1 (83.3?%), eae (28.3?%), F41 (8.3?%), F5 (11.6?%), STa (5?%) and Stx2 (1.6?%) were detected in isolates from healthy calves. Mixed infections with pathotypes Shiga toxin-producing E. coli (STEC)/enteropathogenic E. coli, STEC/enterohaemorrhagic E. coli and STEC/other (eae/F5, Stx1/STa) were detected in five healthy calves. Pathogenic E. coli were identified in 59.26?% of all calves and on 75?% of the dairy farms studied, not only in diarrhoeic (five of six) but also in healthy calves (27 of 48), which demonstrates the importance of this agent in the aetiology of diarrhoea in calves in the state of Minas Gerais.     

Effect of a climate change scenario on <Emphasis Type="Italic">Fusarium equiseti</Emphasis> leaf spot on wild rocket and radish under phytotron simulation

This study was undertaken by simulating the effects of increasing the temperature and CO₂ values on the incidence and severity of F. equiseti on wild rocket (Diplotaxis tenuifolia) and radish (Raphanus sativus), under phytotron conditions. Two sets of 3 trials were carried out in which eight different temperature and CO₂ combinations were tested:1) 400–450 ppm CO₂, 18–22 °C; 2) 800–850 ppm CO₂, 18–22 °C; 3) 400–450 ppm CO₂, 22–26 °C, 4) 800–850 ppm CO₂, 22–26 °C, 5) 400–450 ppm CO₂, 26–30 °C; 6) 800–850 ppm CO₂, 26–30 °C; 7) 400–450 ppm CO₂, 14–18 °C; 8) 800–850 ppm CO₂, 14–18 °C. The temperature and CO₂ levels were significant factors of influence on disease incidence (DI) and severity (DS) in all the trials, and their combination significantly influenced the DI and DS of F. equiseti leaf spot on both hosts. Disease incidence and severity increased on wild rocket at 850 ppm of CO_2, in comparison to 450 ppm, in each tested temperature range. The highest CO₂ value on radish, for all the tested temperature regimes, caused an increase in DI and DS, which resulted statistically significant at the highest tested temperature range. The results obtained in this study add more concern to the possible negative effects of the spread of F. equiseti on vegetables in Italy as well as in other areas suffering from increased temperatures as a consequence of climate changes.     

Vegetative propagation of Apuleia leiocarpa (Vogel) J. F. Macbr

Apuleia leiocarpa is an environmentally and economically significant Atlantic Forest species threat-ened by ongoing exploitation. The vegetative propagation of ...     

The current status of major tick borne diseases in Zambia

Tick-borne diseases occurring in Zambia are assuming more importance as they continue to be a major economic problem not only in Zambia, but in many parts of Eastern, Southern and Central Africa. The current control methods, which include the use of toxic acaricides to kill ticks, and the virulent sporozoite infection and treatment method have limitations. Recombinant vaccines, currently in their experimental stages, offer hope for the future. The use of acaricides is hampered by the development of acaricide resistance and live vaccines are dependent on cold chain facilities, which are a formidable obstacle in the poorly developed infrastructure in parts of Zambia where the vaccine is most needed. Amidst these drawbacks are the results of the recent research on parasites and vector recombinant vaccines which promise to circumvent these problems. The history, current status and attitudes regarding the control of these diseases, taking into account their complexity, are reviewed. The establishment of the well-designed Central Veterinary Research Institute (CVRI) and Japanese International Cooperation Agency (JICA) sponsored veterinary school, both have a potential for high quality research, with access to a wealth of specimens a veritable goldmine of research material. It is thus hoped that this review will stimulate the desire to maximize the value of the tick and tick-borne disease research in both Zambia and the international research community.     

Detection of pathogens in ovine and caprine abortion samples from Sardinia, Italy, by PCR.

During 2003-2005, 399 abortion samples (315 fetuses and 84 placentae) were collected from 107 ovine and caprine farms in northern Sardinia. Tissues from aborted fetuses and placentae were examined by PCR assay to detect DNA from Coxiella burnetii, Chlamydophila abortus, Salmonella enterica Serovar abortusovis, Toxoplasma gondii, and Neospora caninum. The DNA from at least 1 of these 5 infectious agents was amplified in 41% of ovine fetuses, while only 17% of the caprine fetuses yielded a positive amplification result for at least 1 of the 5 agents. Out of a total of 366 ovine aborted samples, T. gondii DNA was detected most frequently (18.1% of fetuses and 13.1% of placentae), followed by S. abortusovis (13% of fetuses and 14.4% of placentae), C. burnetii (10.9% of fetuses, of 9.2% placentae), C. abortus (2.4% of fetuses, 6.5% of placentae), and N. caninum (2% of placentae). In 33 fetuses and 9 placentae, the simultaneous presence of pathogens with different associations was detected. Out of a total of 31 caprine aborted samples, T. gondii was detected most frequently (13% of fetuses and 25% of placentae), followed by C. abortus (12.5% of placentae), C. burnetii (12.5% of placentae), and N. caninum (8.6%).     

Right auricle aneurysm in dogs can be detected with multidetector-row CT and presents with varying morphology

Right auricle aneurysm (RAA) has been reported to be a rare congenital or acquired condition in dogs, however published CT characteristics are limited to a small number of cases. The aim of this 13-year, single-center, retrospective, cross-sectional study was to describe the prevalence and appearance of RAA in a larger group of dogs. Reports of 10,886 dogs that underwent thoracic CT examination for various reasons were reviewed. Computed tomographic data of dogs with presumed RAA (based on published imaging characteristics) were retrieved from the archive. Oblique multiplanar reformatted images were used to record RAA site, shape, and dimensions (neck, maximum height and width). Patients’ sex, age, and body weight were evaluated for any association with the presence of RAA. Presumed RAA was detected in 23/10,886 dogs having thoracic CT in the selected period of time (prevalence 0.21%). Three RAA phenotypes were described: diffuse saccular dilation in 19 of 23 dogs, focal saccular dilation in three of 23 dogs, and fusiform in one of 23 dogs. The bodyweights of dogs with presumed RAA were significantly lower than those of the remaining 10836 dogs without RAA (median 8 kg [IQR 5; range 37.6] and median 16 kg [IQR 23; range 116.9] respectively; P < 0.003. Female sex was also significantly associated with RAA (P = 0.03). Findings indicated that RAA has a low prevalence in dogs, can be detected with CT, can be present in asymptomatic dogs, and can have varying appearances. In this sample of dogs, female sex and low body weight were significantly associated with RAA.