Seroprevalence of Trypanosoma cruzi in stray and pet dogs in Grenada, West Indies.

American trypanosomiasis (Chagas disease) caused by the protozoan parasite Trypanosoma cruzi is endemic to parts of South America and the Caribbean. Infected dogs are important in the epidemiology of the parasite as they can play a role in the transmission of the parasite to humans. A total of 399 dog sera (242 stray and 157 pet dogs) were examined for T. cruzi infection; using a qualitative immunochromatographic dipstick test, based on recombinant antigens specific for American trypanosomiasis (Trypanosoma detect rapid test; InBios international, Inc., Seattle, Washington). Overall seroprevalence for T. cruzi was estimated at 10.5% (95% confidence interval: 7.5% to 13.5%); with stray dogs being significantly more affected (p<0.05, χ2). Results from this study indicate that dogs in Grenada are moderately exposed to T. cruzi compared to other areas in the region.

Spirocercosis in owned and stray dogs in Grenada.

The aim of this retrospective study was to estimate the prevalence of Spirocerca lupi and its associated lesions in owned and stray dogs in Grenada. During 2001-2011 necropsies were carried out on 1022 owned and 450 stray dogs at the pathology diagnostic laboratory, School of Veterinary Medicine, St. George's University, Grenada. Lesions due to S. lupi characterized by focal to multifocal granulomatous esophagitis with aneurysms, mineralized plaques and nodules in the adjacent thoracic aorta were found in 90 (8.8%; 95% confidence interval, 7.1-10.5%) of owned dogs and 64 (14.2%; 95% CI, 11.2-17.6%) of stray dogs. Stray dogs were significantly more affected by spirocercosis than owned dogs (p=0.0022). Of the 90 owned dogs with spirocercosis, 3 dogs had aberrant migration to the thoracic vertebral column with resultant spondylitis; 1 dog each had aberrant migration involving the stomach and the lung. Two dogs had ruptured aorta with hemothorax. Among the 64 stray dogs with spirocercosis, one dog had an esophageal granuloma that transformed into a fibroblastic osteosarcoma; spondylitis due to aberrant migration of S. lupi and hypertrophic osteopathy. We report spirocercosis for the first time in the dogs from a tropical island of Grenada.

Effect of some saturated and unsaturated fatty acids on prostaglandin biosynthesis in washed human blood platelets from (1-14 C)arachidonic acid.

The effects of some saturated (lauric, palmitic and stearic) an unsaturated (linoleic, gamma-linolenic, alpha-linolenic and oleic) fatty acids at 0.1. 0.25 and 0.5 mM concentrations on the in vitro metabolization of (1-14 C) arachidonic acid by washed human blood platelets have been studied. Effects of these fatty acids were studied with intact as well as lysed platelet preparations. With intact platelet preparations it was found that (i) all unsaturated fatty acids enhanced the biosynthesis of TxB2, PGE2, PGD2 and PGF2 alpha, (ii) unsaturated fatty acids reduced the formation of HHT and HETE with the exception of oleic acid which showed very little effect, (iii) unsaturated fatty acids reduced the formation of MDA, whereas palmitic and stearic acids increased its formation and (iv) all unsaturated fatty acids reduced the synthesis of prostaglandin endoperoxides. These results support our previous observations where effects of fatty acids were examined at higher concentrations (10). At 0.1 mM FA concentration, inconsistent results were obtained. With lysed platelet preparations all cyclooxygenase products were reduced in presence of unsaturated fatty acids, whereas HETE formation was reduced only in presence of linoleic and gamma-linolenic acids. Electron micrographs of washed platelet suspensions were obtained with untreated platelet preparations and platelet preparations treated with 0.25 and 0.5 mM linoleic acid concentrations. The results are discussed in the light of a possible soap-like effect of FA salt on platelets.

Influence of EDTA and its metal complexes on lactic acid fermentation.

A comparative study of the influence of EDTA and its metal complexes with Fe, Co, and Ce on lactic acid fermentation by Lactobacillus delbrueckii was done. It was observed that EDTA alone and its complex with Ce could increase the yield of lactic acid up to 1--2%, while complexes of EDTA with Fe and Co enhanced the yield up to 4--5%.

Lactic acid production from molasses by Lactobacillus bulgaricus AU in presence of U, Th, Zr, and Tl.

The influence of uranium, thorium, zirconium, and thallium (I) on fermentation production of lactic acid from molasses by Lacstobacillus bulgaricus AU was studied. It was found that thorium, at lower experimental concentration, and zirconium, at higher experimental concentration, stimulate the acid-producing activity of the bacteria, while uranium and thallium reduce. it.

Influence of mutagenic chemicals on fermentative production of lactic acid by Lactobacillus delbrueckii.

The influence of ammonium fluoride, caffeine, alloxan, and hydrogen peroxide on the fermentative production of lactic acid by Lactobacillus delbrueckii 9649 was studied. It has been found that hydrogen peroxide has an inhibitory effect, while caffeine and alloxan stimulate the fermentation process. The presence of ammonium fluoride does not have any marked influence on the fermentation process.

Fermentative production of lactic acid in presence of some trace elements.

An attempt was made to study the activity of Lactobacillus delbrueckii under the influence of certain trace elements, viz. Tl, U, Th, and Zr. From the results, it was inferred that Tl has comparatively more stimulating effect on the acid-producing activity of the bacteria than U, Th, and Zr.

The influence of mutagenic chemicals on lactic acid fermentation by Lactobacillus bulgaricus AU.

Lactic acid fermentation from molasses by L. bulgaricus AU in the presence of caffeine and ammonium fluoride was studied. It was found that caffeine had a stimulating effect only at lower concentration (0.001%-0.002%), while at high concentration the acid-producing activity of the bacteria was considerably depressed. Ammonium fluoride, at a concentration of 0.001%-0.005%, had a stimulating effect on the activity of the bacteria, maximum activity was observed at a concentration of 0.003%.

Lactic acid production from molasses by mixed population of lactobacilli.

The production of lactic acid from molasses by mixed populations of (1) Lactobacillus bulgaricus AU (isolated from curd) and L. casei (supplied by NCL, Poona-8, India) and (2) L. bulgaricus, L. delbrueckii (supplied by NCL, Poona-8, India), and L. casei was studied. It has been found that association of L. bulgaricus with L. casei slightly enhances the yield of lactic acid, while the mixed population of L. bulgaricus, L. delbrueckii, and L. casei is as effective as L. bulgaricus alone.