Comparison of the effects of cefazolin and ceftriaxone on canine chondrocyte culture.

Cephalosporins (CEFs) are antibiotics frequently used to treat bone infections and septic arthritis. The effects of CEFs on chondrocytes have not been studied until now. Cefazolin (cef1) and ceftriaxone (cef3), first-and third-generation CEFs, were selected to investigate their direct effects on normal and osteoarthritic (OA) primary canine chondrocytes, which were either nonstimulated or stimulated with the pro-inflammatory cytokine IL-1ß. In our results, treatment with CEFs increased the negative effects on both conditioned normal and OA chondrocytes, especially when applied to IL-1ß-stimulated cells (inflammatory stimulus). CEFs significantly decreased cell viability and induced apoptotic cell death in both normal and OA chondrocytes; moreover, treatment with cef1 caused necrotic cell death in OA chondrocytes. Cef3 treatment could increase s-GAG synthesis in normal cells preincubated with IL-1ß, while cef1 had no significant effect. The expression of TNF was clearly downregulated after cef3 treatments, whereas it was upregulated after cef1 treatments. However, cef3 induced stronger downregulation of TIMP1 and the extracellular matrix component genes COL2A1 and ACAN. In conclusion, these results suggest both the cytotoxic effects of CEFs and their adverse effects on chondrogenic marker genes at the transcriptional level, which provide additional insight into the clinical application of cef1 and cef3.

Feline (Felis catus) Skull and Pelvic Morphology and Morphometry: Gender-Related Difference?

This study demonstrates sexual dimorphism of feline bones, based on a morphometric analysis of 38 dried feline skulls and pelvic bones (20 males, 18 females). A total of 44 parameters (skull = 12, mandible = 10, pelvis = 22) were measured using a digital vernier calliper. In morphological observation of these bones, there were three hallmarks indicating a remarkable difference between sexes: the coronoid process of the mandible (accuracy rate = 88.2%); and the os coxae - caudal ventral iliac spine (accuracy rate = 94.4%), and the angle of the ischiatic arch (accuracy rate = 74.3%). In addition, based on morphometric characteristics, six parameters were found to be significantly different (P < 0.05) between males and females, consisting of one in the mandible and five in the pelvis, but no parameters in the skull. Effective equations to discriminate gender were generated through a stepwise discriminant analysis from feline mandible and pelvic bones. Our findings showed that an equation from the pelvic bones, Y = [-16.066*T/O] + [2.559*IC/PS] + [13.357*TTL/ISA] - [4.478], appeared to be more applicable with a 97.3% accuracy rate, while a function from the mandible gave a 64.9% accuracy rate. In conclusion, we suggest that an equation from feline pelvic measurements and three hallmarks, one on the mandible and two on the os coxae, can be used for sex estimation.

Gender-Related Differences in Pelvic Morphometrics of the Retriever Dog Breed.

This study presents the results from a morphometric analysis of 52 dry Retriever dog pelvic bones (30 male, 22 female). A total of 20 parameters were measured using an osteometric board and digital vernier caliper. Six parameters were found to be significantly higher (P < 0.05) in males than in females, while one parameter was significantly higher (P < 0.05) in females than in males. However, none of the measured parameters demonstrated clear cut-off values with no intersect between males and females. Therefore, we generated a stepwise discriminant analysis from all 20 parameters in order to develop a possible working equation to discriminate gender from a dog pelvic bone. Stepwise discriminant analysis was used to create a discrimination function: Y = [82.1*PS/AII] - [50.72*LIS/LI] - [23.09*OTD/SP] + [7.69*SP/IE] + [6.52*IC/OW] + [7.67*ISA/OW] + [20.77*AII/PS] + [504.71*OW/ISA] - [90.84*PS/ISA] - [148.95], which showed an accuracy rate of 86.27%. This is the first study presenting an equation/function for use in discriminating gender from a dog's pelvic measurements. The results can be used in veterinary forensic anthropology and also show that a dog's pelvis presents sexual dimorphisms, as in humans.

Two fluoroquinolones and their combinations with hyaluronan: comparison of effects on canine chondrocyte culture.

Fluoroquinolones (FQs) are frequently used for septic arthritis. Increased antibacterial activity has been associated with mammalian cell cytotoxicity that may increase the risk of developing osteoarthritis. This study compared the direct effects of two different FQs, enrofloxacin (Enro) and marbofloxacin (Mar), on normal primary canine chondrocytes and inflammatory-stimulated chondrocytes, in addition to their administration in combination with hyaluronan (HA). Cell viability, cell apoptosis, s-GAG production, and expression patterns of inflammatory, extracellular matrix (ECM) component and protease genes were measured. Enro co-culturing with HA could modify s-GAG synthesis compared with the negative control group. Co-treatment with both FQs and HA significantly decreased cell viability and induced more total apoptotic cell death compared with the negative control and pre-IL-1ß-stimulated group. Enro regulated IL-1ß-stimulated cells to overexpress IL-1ß, TNF, and MMP3, whereas Mar induced upregulation of PTGS2 and NFKB1 and enhanced the expression of ECM component genes HAS1, COL2A1, and ACAN as well as TIMP1 and MMP9. Simultaneous use of HA with Enro can effectively reduce the expression of IL-1ß, TNF, and MMP3 in pre-IL-1ß-stimulated chondrocytes. These results suggest the beneficial effects of HA in reducing the adverse effects of Enro treatment at the transcriptional level.

The effect of nitric oxide inhibition and temporal expression patterns of the mRNA and protein products of nitric oxide synthase genes during in vitro development of bovine pre-implantation embryos.

This study was conducted to determine the effect of Nitric oxide (NO) inhibition in bovine in vitro development and expression analysis of the three Nitric oxide synthase (NOS) isoforms: endothelial (eNOS), neuronal (nNOS) and inducible (iNOS), mRNA and protein in bovine oocytes and embryos. Selective inhibitor of NOS, N-omega-nitro-l-arginine methyl ester (l-NAME) was applied at different doses (0, 0.1, 1 and 10 mm) in maturation (experiment 1A), culture medium (experiment 1B) and in both maturation and culture media (experiment 1C). No significant differences were observed in cleavage and blastocyst rates when oocytes were matured in the presence of l-NAME as long as the inhibitor was omitted during fertilization and culture. However, significantly lower blastocyst rates were observed when l-NAME was present at higher level (10 mm) in culture medium alone and in both maturation and culture media. In experiment 2, mRNA isolated from triplicate pools of oocytes and embryos (n = 15-20) was subjected to quantitative real time reverse transcription polymerase chain reaction to investigate the expression of eNOS, iNOS and nNOS mRNA in normal IVP bovine oocytes and embryos. While eNOS and iNOS transcripts were detected at higher level in oocytes (immature and mature), two-cell and four-cell stage embryos, the nNOS was detected only in immature oocyte, two-cell and morula stages. In experiment 3, eNOS and iNOS protein expression analysis was performed in IVP oocytes and embryos and both proteins were detected in the cytoplasm and the nuclei (weak) of oocytes and embryos. These data provide the first evidence for the role of NO production and the presence of mRNA and protein products of NOS isoforms during bovine embryogenesis.