Evaluation of Oxidative Stress and Histiocytic Behaviour of Canine TVT using Alpha Antitrypsin

Background: There is scanty literature on evaluation of oxidative stress and alpha antitrypsin marker expression in canine TVT to know its histiocytic behaviour. Since venereal transmissible tumor is one of most important tumor affecting large population of canine, thus, study was conducted to investigate the above based on clinicopathology. Methods: The study was conducted on dogs suffering from transmissible venereal tumor (TVT) for evaluation of clinicopathological alterations, oxidative stress and expression pattern of alpha antitrypsin. Ten bitches and five male dogs with tumour masses seen on the external genitalia were used for the study. Detailed alterations due to TVT with respect to haematobiochemistry, oxidative stress, pathomorphology, proliferation and expression pattern of alpha antitrypsin were assessed. Result: Grossly tumors on the genital area were either pedunculated or sessile and of various shape such as cauliflower, filiform and irregular. Hematological alterations such as normocytic normochromic type of anaemia, thrombocytopenia, neutropenia and lymphocytopenia in TVT cases indicated immunosuppression. Significant alterations in liver enzymes, hypercalcemia and hypoglycaemia were also observed in TVT affected dogs. Increased level of MDA and decreased in concentration of antioxidant enzymes indicated association of oxidative stress in proliferation of tumor and reduction in number of T lymphocytes. Cytological examination revealed characteristic punctuate basophilia and vacuolation in tumour cells. Histopathological examination showed characteristic round cells with a little fibrous septa in a sheet like manner. AgNOR staining indicated moderate proliferative capacity as evidenced by scattered AgNOR dots. TVT cells showed moderate type of immunoreactivity with alpha anti-trypsin confirming its histiocytic origin upon immunohistochemistry.

Comparative Cytogenetics in Four Leptodactylus Species (Amphibia, Anura, Leptodactylidae): Evidence of Inner Chromosomal Diversification in Highly Conserved Karyotypes

With 82 species currently described, the genus <i>Leptodactylus</i> is the most diverse and representative one in the family Leptodactylidae. Concerning chromosomal organization, this genus represents an interesting and underexplored group since data from molecular cytogenetics are incipient, and little is known about the organization and distribution of repetitive DNA elements in the karyotypes. In this sense, this study aimed at providing a comparative analysis in 4 <i>Leptodactylus</i> species (<i>L. macrosternum, L. pentadactylus, L. fuscus,</i> and <i>Leptodactylus</i> cf<i>. podicipinus</i>), combining conventional cytogenetics (Giemsa staining, C-banding, and AgNOR staining) and mapping of molecular markers (18S rDNA, telomeric and microsatellite probes), to investigate mechanisms underlying their karyotype differentiation process. The results showed that all species had karyotypes with 2n = 22 and FN = 44, except for <i>Leptodactylus</i> cf. <i>podicipinus</i> which presented FN = 36. The 18S rDNA was observed in pair 8 of all analyzed species (corresponding to pair 4 in <i>L. pentadactylus</i>), coinciding with the secondary constrictions and AgNOR staining. FISH with microsatellite DNA probes demonstrated species-specific patterns, as well as an association of these repetitive sequences with constitutive heterochromatin blocks and ribosomal DNA clusters, revealing the dynamics of microsatellites in the genome of the analyzed species. In summary, our data demonstrate an ongoing process of genomic divergence inside species with almost similar karyotype, driven most likely by a series of pericentric inversions, followed by differential accumulation of repetitive sequences.

Silver Dots – A Screening and Prognostic Aid in Oral Health

Proper histopathological grading and typing of a tumour plays a significant role in evaluating and assessing the clinical management and prognosis of the tumour. Microscopically sometimes it is difficult in categorizing a tumour into benign or malignant as histopathology does not depict all the features which are of diagnostic and prognostic value. The present study aims :To evaluate the proliferative index of the oral epithelial cells taken from a buccal smear. Materials and method : A total of 90 subjects were included with 30 subjects in each category of normal, smokers and tobacco chewers. The smears were collected from buccal mucosa and applied on the glass slides followed by fixation with alcohol for 30 min and staining of the slides with AgNOR staining as proposed by Bukhari et al (2007). Results: The AgNOR number where more in smokers when compared to normal subjects and was statistically significant. Similarly in chewers it was also comparatively higher when compared to normal and statistically significant. But the AgNOR counts between smoker and tobacco chewer, showed a mean difference of 0.6 and was not statistically significant.

The Karyotype of Salvator merianae (Squamata, Teiidae): Analyses by Classical and Molecular Cytogenetic Techniques

In this study, we analyzed the karyotype of Salvator merianae (Teiidae) from the Brazilian semiarid region using different cytogenetic markers. Chromosomes were examined by classical (Giemsa and AgNOR staining) and molecular (FISH with ribosomal, telomeric, and microsatellite probes) cytogenetic approaches. S. merianae showed a diploid chromosome number of 2n = 38 (10 biarmed macrochromosomes + 28 microchromosomes). No sex-linked chromosome heteromorphisms were observed. Clusters of 18S/28S rDNA were localized in the terminal region of the long arm of pair 2. In addition to the typical telomeric signals, (TTAGGG)n repeats were detected in the pericentromeric region of some macrochromosome pairs, which might indicate the occurrence of chromosomal rearrangements via chromosome fusions. Hybridization signals of the microsatellite probes (GA)n, (GAA)n, and (GAG)n were uniformly distributed across all chromosomes, while (CA)n, (CAA)n, and (CAC)n produced brighter signals in the telomeric and pericentromeric regions of specific chromosome pairs. The comparison with previous studies demonstrates that, despite the wide distribution of S. merianae, the macrostructure organization of the karyotype remained unchanged, showing stability in diploid number and chromosome morphology.

C-banding and AgNOR-staining were still effective complementary methods to indentify chromosomal heteromorphisms and some structural abnormalities in prenatal diagnosis

Background In prenatal diagnosis, CMA has begun to emerge as a favorable alternative to karyotype analysis, but it could not identify balanced translocations, triploidies, inversion and heteromorphisms. Therefore, conventional cytogenetic and specific staining methods still play an important role in the work-up of chromosome anomaly. This study investigated the application of C-banding and AgNOR-staining techniques in prenatal diagnosis of chromosomal heteromorphisms and some structure abnormalities. Results Among the 2970 samples, the incidence of chromosomal heteromorphisms was 8.79% (261/2970). The most frequent was found to be chromosome Y (2.93%, 87/2970), followed by chromosome 1 (1.65 %, 49/2970), 9 (1.52 %, 45/2970), 22 (0.77 %, 23/2970) and 15 (0.64 %, 19/2970). We compared the incidence of chromosomal heteromorphisms between recurrent spontaneous abortion (RSA) group and control group. The frequency of autosomal hetermorphisms in RSA group was 7.63% higher than that in control group (5.78%), while the frequency of Y chromosomal heteromorphisms was 4.76% lower than that in control group (5.71%). Here we summarized 4 representative cases, inv (1) (p12q24), psu dic (4;17) (p16.3;p13.3), r(X)(p11; q21) and an isodicentric bisatellited chromosome to illustrate the application of C-banding or AgNOR-staining, CMA or NGS was performed to detect CNVs if necessary. Conclusions This study indicated that C-banding and AgNOR-staining were still effective complementary methods to identify chromosomal heteromorphisms and marker chromosomes or some structural rearrangements involving the centromere or acrocentric chromosomes. Our results suggested that there was no evidence for an association between chromosomal heteromorphisms and infertility or recurrent spontaneous abortions. Undoubtedly, sometimes we needed to combine the results of CMA or CNV-seq to comprehensively reflect the structure and aberration of chromosome segments. Thus, accurate karyotype reports and genetic counseling could be provided.

Karyotype Evolution and Distinct Evolutionary History of the W Chromosomes in Swallows (Aves, Passeriformes)

As in many other bird groups, data on karyotype organization and distribution of repetitive sequences are also lacking in species belonging to the family Hirundinidae. Thus, in the present study, we analyzed the karyotypes of 3 swallow species (Progne tapera, Progne chalybea, and Pygochelidon cyanoleuca) by Giemsa and AgNOR staining, C-banding, and FISH with 11 microsatellite sequences. The diploid chromosome number was 2n = 76 in all 3 species, and NORs were observed in 2 chromosome pairs each. The microsatellite distribution pattern was similar in both Progne species, whereas P. cyanoleuca presented a distinct organization. These repetitive DNA sequences were found in the centromeric, pericentromeric, and telomeric regions of the macrochromosomes, as well as in 2 interstitial blocks in the W chromosome. Most microchromosomes had mainly telomeric signals. The Z chromosome displayed 1 hybridization signal in P. tapera but none in the other species. In contrast, the W chromosome showed an accumulation of different microsatellite sequences. The swallow W chromosome is larger than that of most Passeriformes. The observed enlargement in chromosome size might be explained by these high amounts of repetitive sequences. In sum, our data highlight the significant role that microsatellite sequences may play in sex chromosome differentiation.