Differentiation of equine induced pluripotent stem cells into mesenchymal lineage for therapeutic use.

In previous work, we established an equine induced pluripotent stem cell line (E-iPSCs) from equine adipose-derived stem cells (ASCs) using a lentiviral vector encoding four transcription factors: Oct4, Sox2, Klf4, and c-Myc. In the current study, we attempted to differentiate these established E-iPSCs into mesenchymal stem cells (MSCs) by serial passaging using MSC-defined media for stem cell expansion. Differentiation of the MSCs was confirmed by analyzing expression levels of the MSC surface markers CD44 and CD29, and the pluripotency markers Nanog and Oct4. Results indicated that the E-iPSC-derived MSCs (E-iPSC-MSCs) retained the characteristics of MSCs, including the ability to differentiate into chondrogenic, osteogenic, or myogenic lineages. E-iPSC-MSCs were rendered suitable for therapeutic use by inhibiting immune rejection through exposure to transforming growth factor beta 2 (TGF-ß2) in culture, which down-regulated the expression of major histocompatibility complex class I (MHC class I) proteins that cause immune rejection if they are incompatible with the MHC antigen of the recipient. We reported 16 cases of E-iPSC-MSC transplantations into injured horses with generally positive effects, such as reduced lameness and fraction lines. Our findings indicate that E-iPSC-MSCs can demonstrate MSC characteristics and be safely and practically used in the treatment of musculoskeletal injuries in horses.

Sertoli Cell Tumor (SCT) in a Captive Black Bear (Ursus americanus).

A black bear of 29-year-old (Ursus americanus) died unexpectedly in captivity without any gross lesions or clinical signs. We identified a firm, lobulated, yellowish tan, and well-circumscribed mass embedded inside the testicular tissue at the time of necropsy. The tumor sections exhibited soft necrotic and hemorrhagic areas beneath its capsule. Histologically, the tumor comprised Sertoli cells arranged in tubules and solid sheets supported by prominent fibrous connective tissues. The Sertoli cells were positive for vimentin and ER-ß expression, whereas it showed negative staining for inhibin-α, cytokeratin 19, and S-100. To the best of our knowledge, this is the rare case report of testicular Sertoli cell tumor in black bear.

Age- and gender-specific estimates of cumulative CT dose over 5 years using real radiation dose tracking data in children.

BACKGROUND: It is necessary to develop a mechanism to estimate and analyze cumulative radiation risks from multiple CT exams in various clinical scenarios in children. OBJECTIVE: To identify major contributors to high cumulative CT dose estimates using actual dose-length product values collected for 5 years in children. MATERIALS AND METHODS: Between August 2006 and July 2011 we reviewed 26,937 CT exams in 13,803 children. Among them, we included 931 children (median age 3.5 years, age range 0 days-15 years; M:F = 533:398) who had 5,339 CT exams. Each child underwent at least three CT scans and had accessible radiation dose reports. Dose-length product values were automatically extracted from DICOM files and we used recently updated conversion factors for age, gender, anatomical region and tube voltage to estimate CT radiation dose. We tracked the calculated CT dose estimates to obtain a 5-year cumulative value for each child. The study population was divided into three groups according to the cumulative CT dose estimates: high, ≥30 mSv; moderate, 10-30 mSv; and low, <10 mSv. We reviewed clinical data and CT protocols to identify major contributors to high and moderate cumulative CT dose estimates. RESULTS: Median cumulative CT dose estimate was 5.4 mSv (range 0.5-71.1 mSv), and median number of CT scans was 4 (range 3-36). High cumulative CT dose estimates were most common in children with malignant tumors (57.9%, 11/19). High frequency of CT scans was attributed to high cumulative CT dose estimates in children with ventriculoperitoneal shunt (35 in 1 child) and malignant tumors (range 18-49). Moreover, high-dose CT protocols, such as multiphase abdomen CT (median 4.7 mSv) contributed to high cumulative CT dose estimates even in children with a low number of CT scans. CONCLUSION: Disease group, number of CT scans, and high-dose CT protocols are major contributors to higher cumulative CT dose estimates in children.

Scintigraphic evaluation of TPLO and CTWO in canine osteoarthritis.

The objective of this study was to evaluate the bone uptake of the bone-seeking radionuclide (99m)technetium-methylene diphosphonate ((99m)Tc-MDP) in order to examine and compare the clinical efficacies of tibial plateau leveling osteotomy (TPLO) and cranial tibial wedge osteotomy (CTWO) for the correction of experimentally induced cranial cruciate ligament (CrCL) transected stifle. Fifteen healthy adult beagle dogs, weighing between 10 and 15 kg, were used for this study. Dogs were assigned to TPLO (n=5), CTWO (n=5) or a control sham group (n =5) and screened with both physical and complete orthopedic examinations. Left CrCLs were transected and two of the three groups were stabilized using TPLO and CTWO. Scintigraphic evaluation of the stifle was performed before TPLO or CTWO surgical repair of the left limb and again at 4, 8 and 12 weeks after surgery. Bone uptake values at 8 and 12 weeks for the TPLO and CTWO groups were not significantly different from their preoperative values, but these differed significantly from the control group at 4, 8 and 12 weeks (p<0.01). No significant differences were found between TPLO and CTWO values. In summary, the relative efficacy of CTWO approximately equals that of TPLO. Moreover, the results of this study confirmed that TPLO and CTWO inhibited the progression of osteoarthritis in CrCL-deficient dogs.

Mouse granulocyte-macrophage colony-stimulating factor enhances viability of porcine embryos in defined culture conditions.

The aim of this study was to determine the effects of mouse granulocyte-macrophage colony-stimulating factor (mGM-CSF) on development of porcine parthenotes and nuclear transferred embryos, and on their expression of implantation-related genes. In the presence of bovine serum albumin, mGM-CSF did not increase the percentage of oocytes that developed to the blastocyst stage and at day 7 did not increase cell numbers of embryos. Addition of 2 ng/ml GM-CSF to protein-free culture medium significantly increased the compaction and blastocoel formation of 1- to 2-cell parthenotes developing in vitro. However, total cell numbers were not increased when they were cultured in the presence of GM-CSF. Semi-quantitative reverse transcriptase polymerase chain reaction revealed that mGM-CSF enhances mRNA expression of the leukemia inhibitory factor receptor, but does not influence interleukin-6 or sodium/glucose co-transporter protein gene expression in blastocyst stage parthenotes. These results suggest that mGM-CSF may enhance viability of porcine embryos developing in vitro in a defined culture medium.