Canine transmissible venereal tumour: a review

Canine transmissible venereal tumour (CTVT) is a contagious venereal tumour of dogs, commonly observed in dogs that are in close contact with one another, or in stray and wild dogs that exhibit unrestrained sexual activity. CTVT represents a unique, naturally transmissible, contagious tumour, where the mutated tumour cell itself is the causative agent and perpetuates as a parasitic allograft in the host. Clinical history, signalment and cytological features are often obvious for establishing a diagnosis though biopsy and histological examination may be needed in atypical cases. Most cases are curable with three intravenous injections of vincristine sulphate at weekly intervals. The role of stray and wild dogs makes the disease difficult to control and necessitates sustained animal birth control in stray dogs along with prompt therapy of the affected dogs. This review captures the manifold developments in different areas embracing this fascinating tumour, including its biology, diagnosis and therapeutic alternatives.     

HTLV-III gag protein is processed in yeast cells by the virus pol-protease

The gag-pol gene of HTLV-III (human T-lymphotropic virus), the virus linked to AIDS (acquired immune deficiency syndrome), was expressed in yeast, and processing of the gag precursor into proteins of the same size as those in the virion was observed. Processing of the gag gene in yeast cells mimics the process that naturally occurs in mammalian cells during maturation of virions. Therefore it was possible to perform mutational analysis of the virus genome to localize the gene that codes for the protease function to the amino terminal coding region of the pol gene. Since this region overlaps the gag gene, it is likely that ribosomal frameshifting occurs from gag to pol. Antibodies in all of the AIDS patients' sera tested recognized the yeast synthesized gag proteins, although the sera showed differences in relative reactivity to the individual gag proteins and the precursor. This yeast system should be valuable not only for production of viral proteins for diagnostic or vaccine purposes but also for analysis of the genetics and biochemistry of viral gene functions--parameters that are difficult to study otherwise with this virus.     

Association studies of lung function in mice

Chronic obstructive pulmonary disease (COPD) is the fourth leading cause of death worldwide and an accelerating decline of lung function is the earliest and a major indicator of the onset of COPD. Therefore it has become necessary to understand the genetic basis of this complex physiological trait in order to determine the potential susceptibility factors of this disease. REINHARD et al (2005) performed the genome wide linkage analysis study with inbred mice having extremely divergent lung function (C3H/HeJ versus JF1/Msf) and identified multiple Quantitative Trait Loci (QTLs) on mouse chromosomes (mCh) 5, 15, 17, and 19 with Logarithm of odd (LOD) scores > or = 4. Significant linkages to total lung capacity (TLC) were detected on mCh 15 and 17, to dead space volume (VD) and lung compliance (C(L)) on mCh 5 and 15, to C(L) on mCh 19, and to diffusing capacity for CO (D(co)) on mCh 15 and 17. Several of the mouse chromosomal regions identified were syntenic to human chromosomal regions identified with linkage to FEV1 (forced expiratory volume-1 second), FVC (forced vital capacity), or FEV1/FVC in separate studies. Using a systematic approach of expression QTL (e-QTL) strategy and exon-wise sequencing of suggested candidate genes followed by predicted protein structure and property, GANGULY et al (2007) recently proposed four candidate genes for lung function in mice. They are superoxide dismutase 3, extracellular [SOD3; mCh 5: V(D)], trefoil factor 2 (TFF2; mCh 17: TLC and D(co)), ectonucleotide pyrophosphatase/phosphodiesterase 2 (ENPP2; mCh 15:TLC and C(L)), and relaxin 1 (RLN1; mCh 19; CL and CL/TLC). As a part of functional validation, gene-targeted Sod3-/- mice were detected with increased conducting airway volume (V(D)/TLC) compared with strain-matched control Sod3+/+ mice, consistent with the QTL on mCh 5. Findings with gene-targeted mice suggested that SOD3 is a contributing factor defining the complex trait of conducting airway volume. The human variation in these genes needs further study both in lung development and in the development of lung disease as a part of translational approach.     

Multiple molecular forms of inhibin in buffalo (Bubalus bubalis) ovarian follicular fluid

Inhibin is a heterodimeric glycoprotein hormone involved in the regulation of FSH release from the anterior pituitary gland and it has been characterized from various animals. Although, multiple molecular forms of inhibin have been reported from different species, however, the molecular nature of inhibin has not been studied in buffaloes. In the present study, attempts were made to identify inhibin in buffalo ovarian follicular fluid. Buffalo ovaries were obtained from the local abattoir and follicular fluid was aspirated from surface follicle (with diameter ?5 mm). A combination of techniques (viz., gel filtration, SDS-PAGE, Western blot etc.) was employed for identification and isolation of inhibin(s). Inhibin bands were detected at 129 and 63 kDa by Western blot analysis in non-reducing conditions. In reduced SDS-PAGE, 63 kDa fraction produced a single band while 129 kDa fraction resolved into four components of 63, 43, 29 and 20 kDa. Out of them only 29, 63 and the native 129 kDa fractions produced bands on Western blot analysis. In total five fractions (63, 54, 39, 29, 25 kDa) were obtained by trypsin digestion of 129 kDa form. However, only 63 and 29 kDa fractions showed immunoreactivity. In this study, for the first time, we have identified two major forms of inhibin (129 and 63 kDa) with little proteolytic cleavage/processing of the large precursor in the buffalo follicular fluid.     

Dietary supplementation with Withania somnifera root powder ameliorates experimentally induced Infectious Bursal Disease in chicken

Tropical Animal Health and Production - Infectious Bursal Disease (IBD) is an economically important, immunosuppressive viral disease of chicken. Withania somnifera, a well-known Indian medicinal...     

Hematological and biochemical studies of stephanofilarial dermatitis in naturally infected cattle of West Bengal, India

This experimental study was conducted to assess the alterations in hematobiochemical values of cattle infected with stephanofilarial microfilariae. Hematological studies of infected cattle revealed significant (P < 0.05) decrease in Hb%, PCV and TEC values whereas TLC values were significantly (P < 0.05) increased. There was insignificant increase in lymphocyte concentration (%), significant (P < 0.05) increase in eosinophil concentration (%) and insignificant decrease in neutrophil concentration (%) in infected cattle in relation to control animal. Biochemical studies revealed that the values of glucose, alkaline phosphatase, AST and ALT were significantly (P < 0.05) increased in infected cattle than control cattle. However, the value of total serum protein was not affected.     

Role of iron and iron chelation therapy in oxygen free radical mediated tissue injury in an ascending mouse model of chronic pyelonephritis

The contribution of iron towards the free radical generation leading to renal tissue damage was assessed using a non-obstructive ascending mouse model for chronic pyelonephritis. The parameters studied include luminol dependent chemiluminescence (LDCL), histopathology and some biochemical investigations. We found that iron enhanced the renal tissue damage and led to renal scarring, an end point in chronic renal inflammation, irrespective of the bacterial strain studied. In addition a role of iron chelation therapy as a treatment for chronic renal inflammation is also suggested.