Molecular characterization of bovine foamy virus and its association with bovine leukemia virus infection in Vietnamese cattle.

The detection of bovine foamy virus (BFV) in Vietnamese cattle was performed using conventional PCR targeting pol and gag genes. Out of 243 tested samples, ten (4.1%) and eight (3.3%) samples were positive for BFV gag and pol DNA, respectively. The prevalence of bovine leukemia virus (BLV) estimated by detection of proviral DNA using nested PCR targeting env gene was 26.7% (65/243). The results of nucleotide sequence alignment and the phylogenetic analysis suggested that Vietnamese BFV strains showed high homology to isolates belonging to either European or non-European clades. There was no significant correlation between BLV and BFV. This study provides information regarding BFV infection and confirms the existence of two BFV clades among Vietnamese cattle for the first time.

Genomic characterization and distribution of bovine foamy virus in Japan.

Bovine foamy virus (BFV) is distributed through worldwide cattle herds. Although the biological features of BFV are not well understood, appearance of clinical manifestation by superinfection with other microorganisms is inferred. In Japan, reports of genomic characterizations and epidemiology of this virus are limited. In this study, we performed whole genomic sequencing of BFV strains Ibaraki and No.43, which were isolated in this country. Additionally, we investigated BFV in geographically distant four daily farms in Japan, to estimate the distribution of BFV and its correlation to bovine leukemia virus (BLV). BFV was distributed throughout Japan; the average positive rate was 12.7%. The nucleotide sequence identities of the isolates were 99.6% when compared with BFV strain isolated in the USA. The phylogenetic tree using env gene sequence showed strains Ibaraki, No.43 and Kagoshima were sorted in the same cluster including the USA and Chinese strains, while Hokkaido strain was in the other cluster including European strains. Although no clear correlation between BFV and BLV could be found, BFV and BLV infections were likely to increase with ages. Our data on epidemiology and characteristics of BFV will provide important information to reveal biological features of BFV.

Detection and genotyping of bovine leukemia virus (BLV) in Vietnamese cattle.

Bovine leukemia virus (BLV) belongs to the genus, Deltaretrovirus of the family, Retroviridae and it is the causative agent of enzootic bovine leukosis. The prevalence of BLV in three provinces in the Red River Delta Region in the North of Vietnam, Hanoi, Vinhphuc and Bacninh was studied from April 2017 to June 2018. A total of 275 blood samples collected from cattle were used for serum isolation and DNA extraction. Of these samples, 266 sera were subjected to ELISA test for detecting antibody against BLV gp51 protein and 152 DNA samples were used to detect the 444 bp fragment corresponding to a part of the gp51 region of the env by nested PCR. The results showed that 16.5% (n=44) and 21.1% (n=32) of samples were positive for BLV gp51 antibody and BLV proviral DNA, respectively. Phylogenetic analysis of the partial (423 bp) and complete (913 bp) BLV env-gp51 gene indicated that Vietnamese strains were clustered into genotypes 1, 6 and 10 (G1, G6 and G10). Of those genotypes, G1 genotype was dominant; G6 strains were designated as G6e and G6f subgenotypes; the existence of genotype 10 was confirmed for the first time in Vietnam. The present study provides important information regarding the prevalence of BLV infection and genetic characteristics of BLV strains identified in Vietnam, contributing to promote the establishment of disease control and eradication strategies in Vietnam.

Contrast-enhanced computed tomography findings of canine primary renal tumors including renal cell carcinoma, lymphoma, and hemangiosarcoma.

In veterinary medicine, abdominal ultrasonography is used to rank the differential diagnosis of renal lesions. However, a conventional sonographic examination may show nonspecific findings. The purpose of this study was to assess the computed tomography (CT) findings of canine renal tumors, including renal cell carcinoma (RCC), lymphoma, and hemangiosarcoma (HSA). In this retrospective study, the following CT parameters were recorded for each dog: 1) extent of renal involvement of tumors, 2) enhancement pattern, 3) number of renal tumors, 4) renal tumor vessel enhancement in the corticomedullary phase, 5) presence of lymphadenopathy and lung metastasis, and 6) attenuation values of the renal tumors on the pre- and post-contrast corticomedullary, nephrographic, and excretory phase images. Fifteen dogs met the inclusion criteria, of which nine had RCCs, four had lymphomas, and two had HSAs. RCCs tended to show heterogeneous enhancement and unilateral renal involvement, and vessel enhancement was detected in the corticomedullary phase in dogs with RCC. Conversely, renal lymphomas showed homogeneous enhancement, bilateral renal involvement, and multiple masses; in these dogs, no vessel enhancement was detected in the corticomedullary phase, and the incidence of lymphadenopathy was low. However, in dogs with lymphadenopathy, the renal lymphoma was associated with regionally severe lymphadenopathy. Finally, renal HSAs tended to show heterogeneous enhancement with a non-enhanced area and unilateral renal involvement; in these dogs, vessel enhancement was detected in the nephrographic phase, with the enhancement expanding around the vessel. These findings had no significant differences. Further studies with a larger sample size are required to examine the association between CT and histopathological findings.

Contrast-enhanced computed tomography may be helpful for characterizing and staging canine gastric tumors.

In humans, computed tomography (CT) is a widely performed technique for the diagnosis and staging of gastric tumors. The purpose of this retrospective case series study was to describe CT findings in a group of dogs with confirmed gastric tumors. For each included dog, the following CT parameters were recorded: gastric tumor location, tumor shape, gastric involvement pattern, tumor enhancement pattern in early and late phases, presence and location of lymphadenopathy, gastric tumor attenuation values, attenuation values of enlarged lymph nodes, maximum short-axis diameter (mm) of enlarged lymph node, maximum long-axis diameter (mm) of enlarged lymph node, and short-axis diameter to long-axis diameter ratio (short axis/long axis). A total of 16 dogs met inclusion criteria and had the following final diagnoses: five lymphoma, six adenocarcinoma, three inflammatory polyps, and two leiomyoma. In the early- and delayed-phase postcontrast images, the mean CT attenuation value for lymphoma was lower than that of other gastric tumors. Lymphadenopathy was widespread in lymphomas and regional in adenocarcinomas. Lymphadenopathy was not detected in leiomyomas. Lymph node measurements in lymphoma were larger than lymph node measurements in adenocarcinoma. Although there were overlapping findings for the different types of gastric tumors, contrast-enhanced CT provided helpful information for characterizing gastric tumors based on the following criteria: early and late enhancement patterns, the site of origin of the mass lesion, and extent of local invasion and distant metastases. Lymphoma should be considered for canine gastric tumors with low mean attenuation values during early- and delayed-phase postcontrast images, and widespread, bulky, and rounded lymphadenopathy.

Seminal plasma induces programmed cell death in cultured peripheral blood mononuclear cells.

Immunosuppressive properties of seminal plasma inhibit the recovery of infectious HIV from semen, and led to the view early in the pandemic that semen HIV was transmitted principally by infected semen cells. More recent studies have revealed significant titers of HIV RNA in seminal plasma, however, even from men receiving successful antiviral therapy. Thus, studies of infectious HIV in seminal plasma are important to understanding sexual transmission and response to therapy. The present studies were undertaken to determine whether seminal plasma immunosuppression is mediated by the induction of programmed cell death (PCD). Peripheral blood mononuclear cells (PBMCs) were cultured without or with phytohemagglutinin and seminal plasma from normal donors, or men postvasectomy, or seminal vesicle protein collected at surgery. PBMC survival was measured at 3, 6, and 18 hr of culture; cells were examined for evidence of PCD by uptake of the fluorescent dye YO-PRO, and for fragmented nuclear DNA by the TUNEL assay. Approximately 90% of PBMCs cultured with seminal plasma from intact or vasectomized men were lost during 18 hr of culture; seminal vesicle protein did not induce cell loss. PCD assays were positive for PBMCs exposed to the seminal plasma, and negative for PBMCs cultured with seminal vesicle protein. Serum was not required for PCD induction. A 3-hr pulse with seminal plasma was sufficient to initiate PCD. These findings indicate that PCD induction accounts for the cytotoxic properties of semen, that the PCD is not the result of semen amine oxidases, and either that substances produced by seminal vesicles only at ejaculation, or by the prostate, are responsible for PCD induction.