CYTOMETRY AND KARYOMETRY IN TRYPANOSOMA-CRUZI

A total of 991 Trypanosoma cruzi cells, from four laboratory stocks, including the three differentiation forms, had their cellular outlines, nuclei and kinetoplasts measured at 9000 x magnification. Data on the identifiable cell cycle stages were used to search for intraspecific and biological cycle heterogeneity.Cellular areas (CA) in the interphasic differentiation forms produced ratios of 1.07 for culture epimastigotes (E), 1 for blood trypomastigotes (T), and 0.86 for tissue forms (A). Homogeneity in terms of nuclear (NA) and kinetoplast (KA) areas prevailed among the stocks, with differences of at most 6%, for modal NA of strains CL and Y. NA of T-form was larger than the basic NA of early G1 A-form. T-form kinetoplast volume was 3-fold that of A-form K-DNA nucleoids.One of the two recently divided kinetoplasts in mitotic E-form did not correlate with CA, indicating that mitochondrial division was unequal. The KA of CL strain T-form did not correlate with NA, suggesting a mitochondrial disfunction in this thermosensitive strain.The CL strain T-form was more heterogeneous than the Y strain for all characters, showing greater frequency of large values, even reaching the G2 levels. This heterogeneity was interpreted as functional, consequent to the thermosensitivity of the CL strain. Precocious bursting of CL strain host cells would lead to the polymorphic T-forms. Post-S phase trypomastigotes could start division soon after penetration of host cells.

HIERARCHICAL VERSUS NONHIERARCHICAL PATTERNS OF GENETIC DISTANCES AMONG POPULATIONS - A SIMULATION STUDY

A simulation study was made of the effects of mixing two evolutionary forces (natural selection and random genetic drift), combined in a single data matrix of gene frequencies, on the resulting genetic distances among populations. Twenty-one, kinds of simulated gene frequencies surfaces, for 15 populations linearly distributed over geographic space, were used to construct 21 data matrices, combining different proportions of two types of surfaces (gradients and random surfaces). These matrices were analysed by Unweighted Pair-Group Method - Arithmetic Averages (UPGMA), clustering and Principal Coordinate Analysis. The results obtained show that ordination is more accurate than UPGMA in revealing the spatial patterns in the genetic distances, in comparison with results obtained using the Mantel test comparing directly genetic and geographic distances.

Drosophila melanogaster P transposable elements: mechanisms of transposition and regulation

The molecular mechanisms that control P element transposition and determine its tissue specificity remain incompletely understood, although much information has been compiled about this element in the last decade. This review summarizes the currently available information about P element transposition, P-M hybrid dysgenesis and P cytotype features, P element-encoded repressors, and regulation of transposition.

Níveis de cloreto de sódio em rações para frangos de corte

A trial was carried out using 1,000 day-old chicks to evaluate levels of NaCl (0.30, 0.45, 0.60, 0.75 and 0.90%) in diets. Water and feeding with 20.1 and 18.2% CP, 2, 900 and 2,950 kcal/kg ME respectively for initial and finishing phases were offered ad libitum. High levels of NaCl (0.60, 0.75 and 0.90%) increased the water intake and water:feed ratio during the first 21 days (P<0.05). Whitin the period of 21-42 days only water intake increased (P<0.05). Body weight, feed and water intake, mortality were higher (P<0.05)for males. High levels of NaCl (0.60, 0.75 and 0.90%) increased (P<0.05) body weight, water intake, water:feed ratio and moist litter during the trial. The supplementation of high levels of NaCl increased performance, bur implied in higher litter moisture.

Ocular alterations in dogs naturally infected by Leishmania (Leishmania) chagasi

Ocular conditions, anti-Leishmania antibodies and total protein of the aqueous humor were studied in dogs naturally infected by Leishmania ( Leishmania) chagasi. Fifty dogs were analyzed and assigned into two groups of 25 animals each. All animals were submitted to routine ophthalmic exam. Results showed that 76% of the affected animals presented ocular signs, being uveitis the predominant. The mean of total protein in the aqueous humor of animals with uveitis was higher ( P < 0.05) when compared to the mean of animals with other ocular signs or no clinical sign. The anti- Leishmania chagasi antibody values in plasma were superior to those found in the aqueous humor (P < 0.05).

Immunohistochemical evaluation of Ki-67 and PCNA in canine mammary neoplasias: Correlation with prognostic factors and clinical outcome

E-cadherin is a cell-cell adhesion molecule and low e-cadherin expression is related to invasiveness and may indicate a bad prognosis in mammary neoplasms. The expression of cell proliferation markers PCNA and especially Ki-67, has also proved to have a strong prognostic value in this tumor class. The expression of these markers was related to the clinical-pathological characteristics of 73 surgically removed mammary tumors in female dogs by immunohistochemistry. There was no statistical correlation between these markers and death by neoplasm, survival time and disease-free interval. However, the loss of e-cadherin expression and marked Ki-67 expression (p=0.016) were considered statistically significant for the diagnosis (p=0.032). When evaluated as independent factors, there was evidence of the relationship between the loss of e-cadherin expression and high PCNA expression with changes in the body status (divided into obese, normal and cachectic) of female dogs (p=0.030); there was also evidence of the relationship between pseudopregnancy and e-cadherin alone (p=0.021) and for ulceration and PCNA alone (p=0.035). The significant correlation between the markers expression and these well known prognostic factors used individually or in combination suggests their prognostic value in canine mammary tumors.

Mummified papyraceous fetuses in the abdominal cavity of an elderly female dog with pyometra

This paper reports on a rare case of fetal papyraceous mummification after asymptomatic uterine rupture in an elderly female dog with pyometra. The patient had a history of mating six months before the examination but no apparent signs of gestation or parturition. Exploratory laparotomy was used to identify a rupture of the left uterine horn and the presence of cystic endometrial hyperplasia and pyometra. Two mummified papyraceous fetuses were observed in the abdominal cavity and had adhered to the spleen, pancreas, intestine and omentum. Ovariehysterectomy and corrective surgery were performed. The patient had remained healthy after uterine rupture until a new estrous cycle and the development of pyometra. Bitches that are 10 years old or more are predisposed to implantation failure, pregnancy or parturition problems and they should not be breed to avoid complications.

Immunohistochemical and molecular expression of laminin-332 gamma-2 chain in canine mammary tumors

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Distribution of 45S and 5S rDNA sites in 23 species of Eleocharis (Cyperaceae)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Analysis of Escherichia coli isolated from bovine mastitic milk

Rangel P. & Marin J.M. 2009. Analysis of Escherichia coli isolated from bovine mastitic milk. Pesquisa Veterinaria Brasileira 29(5): 363-368. Departamento de Morfologia, Estomatologia e Fisiologia, Faculdade de Odontologia de Ribeirao Preto, Universidade de São Paulo, Avenida do Cafe s/n, Campus USP, Ribeirao Preto, SP 14040-904, Brazil. E-mail: jmmarin@forp.usp.brMastitis has been recognized for some time as the most costly disease in dairy herds. From February to November 2004, 670 samples of bovine mastitic milk from which 231 Escherichia coli strains were isolated, were collected from two Brazilian states. The strains were screened for the presence of Shiga toxin-producing (stx 1 and stx 2) and intimin (eae) genes. Twenty (8.6%) strains were detected by PCR to harbor the Shiga toxin genes (8 the stx 1 gene, 12 the stx 2 gene and none both of them). Two (0.8%) of the Escherichia coli strains studied were eae positive non Shiga toxin-producing. The strains were also examined for resistance to 12 antimicrobial agents. The predominantly observed resistance was to tetracycline (92.2%), streptomycin (90.4%), nalidixic acid (88.3%), amikacin (86.5%) and cephalothin (84.8%). Multidrug resistance was found among 152 isolates (65.8%).

Trypanosoma vivax infection dynamics in a cattle herd maintained in a transition area between Pantanal lowlands and highlands of Mato Grosso do Sul, Brazil

Trypanosoma vivax outbreaks in beef cattle in the Pantanal region of Mato Grosso do Sul state, Brazil, causes relevant economical impact due to weight loss, abortion and mortality. Cattle moved from the Pantanal to adjacent areas of this ecosystem for breeding and fattening is a common feature. Therefore an epidemiological study on breeding cows in the transition area between Pantanal lowland and adjacent highlands of Mato Grosso do Sul was performed to determine the T. vivax infection dynamics and outbreak risk. Three experimental groups were formed: Group 1 consisted of cows parasitologically negative by the Woo test and in the enzyme-linked immunosorbent assay for T. vivax antibody detection (Tv-ELISA-Ab); Group 2 parasitologically negative and positive in the Tv-ELISA-Ab; and in Group 3 cows were parasitologically positive and with positive reactions in the Tv-ELISA-Ab. During 24 months, the cows' dislodgment between the above established groups was monitored by Woo test and Tv-ELISA-Ab exams. The tabanid population was also monitored and the highest number occurred during the rainy season. Although parasitemias were detected only in the first four samplings of the experimental period, the cows could be considered as trypanotolerant, because no clinical signs were observed. Despite the higher T. vivax incidence during the dry season, no disease symptoms were seen. Even though T. vivax epidemiological situation in the herd was characterized as endemic with seasonal variation, the probability of outbreaks was null within the conditions of the study.

Concentração plasmática de diclofenaco sódico em cães, submetidos à fonoforese

The aim of this study was to evaluate the plasma concentration of diclofenac sodium (DS) in dogs submitted to diclofenaco phonophoresis and to evaluate if phonophoresis induces greater absorption of this drug in dogs. Five dogs were used in eight different groups at different times: One group received oral administration of 40mg of DS per dog and seven groups received topical application of emulgel DS. The topical application area was 20cm(2). A continuous ultrasound frequency of 1MHz and intensity of 0.4W cm(-2) was used. Blood collections were performed before the treatment (T0), and 1h (T1) and 4h (T2) after ultrasound application for all groups. DS concentrations in plasma were measured by high performance liquid choramatohraphy (HPLC). There was significant increase of DS plasma concentration only at T1 in the oral administration group. It was not possible to detect any concentration of DS in the plasma of dogs after topical application of DS, even after DS phonophoresis. The facilitation of transdermal penetration by ultrasound has not been verified under the protocol specified in this research.

Potencial mirmecológico na vetoração mecânica de helmintos em gatis

Vector potential of ants in mechanic dissemination of helminthes in a cat rescue center was analyzed in this study. Ants walking over cat's food and feces were collected and conditioned in distilled water. Cat feces were collected too. Ants were identified and the water where they were conditioned was observed on optic microscope. It was made the simple sedimentation technique to analyze feces. The results show that ants species Pheidole and Paratrechina can be potential vectors of nematode eggs, mainly Ascaridida, Toxocaridae.

Anticorpos para Leptospira spp., Toxoplasma gondii e Neospora caninum em cães errantes albergados em canil privado

The serological profile of 300 mongrel dogs of various ages and gender were investigated. Animals were captured in the streets and afterwards directed to a private kennel in Avare city (SP) to search for leptospirosis, toxoplasmosis, and neosporosis. Blood samples were obtained from jugular or cephalic vein for the obtention of sera. The microscopic agglutination test (MAT) was used to leptospirosis. MAT detect the prevalence of 9.3%. The most frequent reactant serovars were Bratislava (35.7%), Cynopteri (17.9%), Autumnalis (14.3%), and Copenhageni (10.7%), besides 7.1% to others serovars: Icterohaemorrhagiae, Canicola, and Hardjo. The modified agglutination test used for the diagnosis of toxoplasmosis showed 26% of positive animals, with titers varying from 16 to 256, with 16 in 3.3%, 64 in 13.7%, and 256 in 9% of the samples. To canine neosporosis, it was used the indirect fluorescent antibody test, and two animals (0.7%) demonstrated antibodies with titers 25 and 100. The results show the participation of the animals in the epidemiological chain of the researched diseases.

Variability of esterase patterns in adult flies of the saltans species group of Drosophila (subgenus Sophophora)

Esterases are known for their involvement in several physiological processes and high degree of polymorphism, in many organisms. Such polymorphism has been used to characterize species and species groups and to study genetic changes occurred in their evolutionary history. In the present study, the esterase patterns of 19 strains from 10 species representative of the five subgroups of the saltans species group were analyzed using polyacrylamide gel electrophoresis and alpha- and beta- naphthyl acetates as substrates. Fifty-one esterase bands were detected and classified as 31 alpha-esterases, 18 beta-esterases and two alpha/beta-esterases. on the basis of the inhibition patterns using Malathion and eserine sulfate, 34 bands were classified as carboxylesterases, 14 as acethylesterases and three as cholinesterases. Ten gene loci were tentatively established on the basis of data on band position in the gel, substrate preference and inhibition pattern. Twenty bands were species-specific, the remaining being shared by species from the same or different subgroups. Bands detected exclusively in males and bands with a different frequency or degree of expression between sexes were also detected. In the gels prepared for analysis of gene expression in the body parts (head, thorax and abdomen), the degree of expression of the beta-esterases was higher in the thorax, while the alpha-esterases were expressed predominantly in the abdomen and thorax. A global view of the data available at present on the esterases of the species from the saltans group and their degree of polymorphism are presented, as well as the possibility of using some beta-esterases, because of their characteristics in the gels, as markers for species identification.