Experimental infection of Leishmania (Mundinia) martiniquensis in BALB/c mice and Syrian golden hamsters.

Our objective was to investigate clinical progression, presence of parasites and DNAs, parasite loads, and histological alterations in BALB/c mice and Syrian golden hamsters after intraperitoneal inoculation with Leishmania (Mundinia) martiniquensis promastigotes with a goal to choosing an appropriate animal model for visceral leishmaniasis. Infections were monitored for 16 weeks. Infected BALB/c mice were asymptomatic during the infection course. Parasite DNAs were detected in the liver at week 8 of infection, followed by clearance in most animals at week 16; whereas in the spleen, parasite DNAs were detected until week 16. These results are correlated to those obtained measuring parasite loads in both organs. No parasite DNA and no alteration in the bone marrow were observed indicating that no dissemination occurred. These results suggest the control of visceralization of L. martiniquensis by BALB/c mice. In hamsters, weight loss, cachexia, and fatigue were observed after week 11. Leishmania martiniquensis parasites were observed in tissue smears of the liver, spleen, and bone marrow by week 16. Parasite loads correlated with those from the presence of parasites and DNAs in the examined tissues. Alterations in the liver with nuclear destruction and cytoplasmic degeneration of infected hepatocytes, presence of inflammatory infiltrates, necrosis of hepatocytes, and changes in splenic architecture and reduction and deformation of white pulp in the spleen were noted. These results indicate a chronic form of visceral leishmaniasis indicating that the hamster is a suitable animal model for the study of pathological features of chronic visceral leishmaniasis caused by L. martiniquensis.

Ex vivo and in vivo characterization of cold preserved cartilage for cell transplantation.

Due to the inconvenient and invasive nature of chondrocyte transplantation, preserved cartilage has been recognized as an alternative source of chondrocytes for implantation. However, there are major concerns, in particular, the viability and quality of the chondrocytes. This study investigated the biochemistry and molecular characterization of chondrocytes isolated from preserved cartilage for purposes of transplantation. Ex vivo characterization was accomplished by storing human cartilage at either 4 or -80 °C in a preservation medium. Microscopic evaluation of the preserved cartilage was conducted after 1, 2, 3 and 6 weeks. The chondrocytes were isolated from the preserved cartilage and investigated for proliferation capacity and chondrogenic phenotype. Transplantation of chondrocytes from preserved cartilage into rabbit knees was performed for purposes of in vivo evaluation. The serum cartilage degradation biomarker (WF6 epitopes) was evaluated during the transplantation procedure. Human cartilage preserved for 1 week in a 10 % DMSO chondrogenic medium at 4 °C gave the highest chondrocyte viability. The isolated chondrocytes showed a high proliferative capacity and retained chondrogenic gene expression. Microscopic assessment of the implanted rabbit knees showed tissue regeneration and integration with the host cartilage. A decreased level of the serum biomarker after transplantation was evidence of in vivo repair by the implanted chondrocytes. These results suggest that cartilage preservation for 1 week in a 10 % DMSO chondrogenic medium at 4 °C can maintain proliferation capacity and the chondrogenic phenotype of human chondrocytes. These results can potentially be applied to in vivo allogeneic chondrocyte transplantation. Allogeneic chondrocytes from preserved cartilage would be expected to maintain their chondrogenic phenotype and to result in a high rate of success in transplanted grafts.

Inhibition of 5-alpha reductase attenuates cardiac oxidative damage in obese and aging male rats via the enhancement of antioxidants and the p53 protein suppression.

In aging and metabolic syndrome oxidative stress is a causative factor in the cardiovascular pathology. Upregulation of 5-⍺ reductase is associated with cardiac hypertrophy but how inhibition of 5-⍺ reductase affects cardiometabolic function during oxidative damage under those conditions is unclear. Our hypothesis was that Finasteride (Fin), a 5-⍺ reductase inhibitor, promotes an antioxidant response, leading to an improvement in cardiac function in obese and aging rats. Male rats were divided into 3 groups including normal diet (ND) fed rats, ND-fed rats treated with d-galactose (D-gal) to induce aging, and high-fat diet (HFD) fed rats to induce obesity. Rats received their assigned diet or D-gal for 18 weeks. At week 13, rats in each group were divided into 2 subgroups and received either a vehicle or Fin (5 mg/kg/day, oral gavage). Cardiometabolic and molecular parameters were subsequently investigated. Both D-gal and HFD successfully induced cardiometabolic dysfunction, oxidative stress, mitochondrial dysfunction, and DNA fragmentation. Fin treatment did not affect metabolic disturbances; however, it reduced cardiac sympathovagal imbalance, cardiac dysfunction through the inhibition of oxidative stress and promoted antioxidants, resulting in reduced p53 protein levels and DNA fragmentation. Surprisingly, Fin induced insulin resistance in ND-fed rats. Fin effectively improved cardiac function in both models by enhancing antioxidant levels, suppressing oxidative stress and DNA fragmentation. However, Fin treatment did not confer any beneficial effects on metabolic status. Fin administration effectively improved cardiac sympathovagal balance and cardiac function in rats with oxidative damage induced by either D-gal or HFD.

Sequence analysis of porcine kobuvirus VP1 region detected in pigs in Japan and Thailand.

Porcine kobuvirus is a new candidate species of the genus Kobuvirus in the family Picornaviridae, and information is still limited. The identification of porcine kobuvirus has been performed by the sequence analyses of the 3D region of the viruses. Therefore, the purpose of this study was to characterize the molecular properties of VP1 nucleotide sequences of the porcine kobuviruses isolated from porcine stool samples in Japan during 2009 and Thailand between 2006 and 2008. In addition, previous identification of a unique porcine kobuvirus; Japanese H023/2009/JP, which is a bovine kobuvirus-like strain based on sequence analysis of the 3D region, was also included in this study. All of the strains were amplified by the VP1-specific primer pair: the amplicons were subjected to direct sequencing and compared with the VP1 nucleotide sequences of reference strains. The VP1 sequences of strains from the GenBank database revealed high nucleotide sequence identity at 84.3-100%. On the other hand, the nucleotide identities among the 15 porcine kobuvirus strains analyzed in this study ranged from 78.8 to 99.8%. The results revealed that diversity of the strains in this study were higher than those of the strains in previous studies. Furthermore, it was found that the VP1 region of the bovine kobuvirus-like strain, H023/2009/JP, clustered with nine porcine kobuvirus strains that were isolated in Thailand and Japan. Since this strain was previously found to be closely related to bovine kobuviruses in the 3D gene region, it may be a natural recombinant.