Risk factors for fracture by same-level falls among workers across sectors: a cross-sectional study of national open database of the occupational injuries in Japan.

OBJECTIVES: The hospitalisation rate for work-related injuries among older workers is double that of younger workers; however, the risk factors for same-level fall fractures sustained during industrial accidents remain unclear. This study aimed to estimate the influence of worker age, time of day and weather conditions on the risk of same-level fall fractures in all industrial sectors in Japan. STUDY DESIGN: This was a cross-sectional study. METHODS: This study used the population-based national open database of worker death and injury reports in Japan. In total, 34,580 reports of occupational same-level falls between 2012 and 2016 were used in this study. Multiple logistic regression analysis was performed. RESULTS: In primary industries, workers aged ≥55 years had a 1.684 times greater risk of fracture (95% confidence interval [CI]: 1.167-2.430) compared with workers aged ≤54 years. In tertiary industries, relative to the odds ratio (OR) of injuries recorded at 0:00-2:59 a.m., the ORs recorded at 6:00-8:59 p.m., 6:00-8:59 a.m., 9:00-11:59 p.m. and 0:00-2:59 p.m. were 1.516 (95% CI: 1.202, 1.912), 1.502 (95% CI: 1.203-1.876), 1.348 (95% CI: 1.043-1.741) and 1.295 (95% CI: 1.039-1.614), respectively. The risk of fracture increased with a 1-day increase in the number of snowfall days were per month in secondary (OR = 1.056, 95% CI: 1.011-1.103) and tertiary (OR = 1.034, 95% CI: 1.009-1.061) industries. The risk of fracture decreased with every 1-degree increase in the lowest temperature in primary (OR = 0.967, 95% CI: 0.935-0.999) and tertiary (OR = 0.993, 95% CI: 0.988-0.999) industries. CONCLUSIONS: With the increasing number of older workers and changing environmental conditions, the risk of falls in the tertiary sector industries is increasing, particularly just before and just after shift change hours. These risks may be associated with environmental obstacles during work migration. It is also important to consider the weather-associated risks of fracture.

Effect of coordinator-based osteoporosis intervention on quality of life in patients with fragility fractures: a prospective randomized trial.

We examined the effects of the coordinator-based intervention on quality of life (QOL) in the aftermath of a fragility fracture, as well as factors predictive of post-fracture QOL. The coordinator-based interventions mitigated the decrease in QOL. Secondary fracture after primary fracture, however, was a significant predictor of lower QOL. PURPOSE: This study aimed to determine the effects of the coordinator-based intervention on QOL in the aftermath of a fragility fracture, as well as factors predictive of post-fracture QOL, in an Asian population. METHODS: Patients with new fractures in the intervention group received the coordinator-based intervention by a designated nurse certified as a coordinator, within 3 months of injury. QOL was evaluated using the Japanese version of the EuroQol 5 Dimension 5 Level (EQ-5D-5L) scale  before the fracture (through patient recollections) and at 0.5, 1, and 2 years after the primary fracture. RESULTS: Data for 141 patients were analyzed: 70 in the liaison intervention (LI) group and 71 in the non-LI group. Significant intervention effects on QOL were observed at 6 months after the fracture; the QOL score was 0.079 points higher in the LI group than in the non-LI group (p=0.019). Further, the LI group reported significantly less pain/discomfort at 2 years after the fracture, compared to the non-LI group (p=0.037). In addition, secondary fractures were found to significantly prevent improvement and maintenance of QOL during the recovery period (p=0.015). CONCLUSION: Short-term intervention effects were observable 6 months after the primary fracture, with the LI group mitigated the decrease in QOL. Few patients in the LI group reported pain/discomfort 2 years after the fracture, but there is uncertainty regarding its clinical significance. Secondary fracture after initial injury was a significant predictor of lower QOL after a fracture.

Efficiency of coordinator-based osteoporosis intervention in fragility fracture patients: a prospective randomized trial.

We examined the effectiveness of coordinators' interventions to prevent secondary fractures in patients with fragility fractures. These coordinator-based interventions improved bone density assessment implementation and treatment rates, and enhanced treatment persistence rates in the early stages following fractures. INTRODUCTION: This study aimed to determine the efficiency of coordinator-based osteoporosis intervention in fragility fracture patients during a 2-year period. METHODS: A prospective intervention randomized control study was conducted at seven medical facilities from January 2015 to March 2017. Postmenopausal women and men over 50 years old with fragility fractures were randomly divided into the coordinator intervention (LI; 70 patients) and without intervention (non-LI; 71 patients) groups. The osteoporosis treatment rate, osteoporosis treatment persistence rate, fall rate, fracture incidence rate, and bone density measurement rate 3 months, 6 months, 1 year, and 2 years after registration were compared between the two groups. Non-parametric tests were used to analyze data at each inspection period. RESULTS: The osteoporosis treatment initiation rate was significantly higher in the LI group than in the non-LI group (85.7% vs. 71.8%; p = 0.04). The LI group had significantly higher bone density assessment implementation rates than the non-LI group at the time of registration (90.0% vs. 69.0%; p = 0.00) and 6 months after registration (50.0% vs. 29.6%; p = 0.01), but not 1 or 2 years after registration. In addition, no significant differences in fall or fracture incidence rates were found between the two groups. CONCLUSION: The coordinator-based interventions for fragility fractures improved bone density assessment implementation and treatment rates and enhanced treatment persistence rates in the early stages following bone fractures. The findings suggest that liaison intervention may help both fracture and osteoporosis physicians for the evaluation of osteoporosis and initiation and continuation of osteoporosis medication.

Reducing glucocorticoid dosage improves serum osteocalcin in patients with rheumatoid arthritis-results from the TOMORROW study.

UNLABELLED: Decreasing the daily dose of glucocorticoids improved bone metabolic marker levels in patients with rheumatoid arthritis. However, changes in disease activity did not influence bone metabolism. Bone metabolism might thus remain uncontrolled even if disease activity is under good control. Decreasing glucocorticoid dosage appears important for improving bone metabolism. INTRODUCTION: Patients with rheumatoid arthritis (RA) develop osteoporosis more frequently than healthy individuals. Bone resorption is increased and bone formation is inhibited in patients with RA, and glucocorticoid negatively affects bone metabolism. We aimed to investigate factors influencing bone metabolic markers in patients with RA. METHODS: We started the 10-year prospective cohort Total Management of Risk Factors in Rheumatoid Arthritis Patients to Lower Morbidity and Mortality (TOMORROW) study in 2010. We compared changes in urinary cross-linked N-telopeptide of type I collagen (uNTx) and serum osteocalcin (OC), as markers of bone resorption and formation, respectively, in 202 RA patients and age- and sex-matched volunteers between 2010 and 2011. We also investigated factors influencing ΔuNTx and ΔOC in the RA group using multivariate analysis. RESULTS: Values of ΔuNTx were significantly lower in patients with RA than in healthy controls (-0.51 vs. 7.41 nmol bone collagen equivalents (BCE)/mmol creatinine (Cr); p = 0.0013), whereas ΔOC values were significantly higher in RA patients (0.94 vs. 0.37 ng/ml; p = 0.0065). Changes in prednisolone dosage correlated negatively with ΔOC (ß = -0.229, p = 0.001), whereas changes in disease activity score, bisphosphonate therapy, and period of biologics therapy did not correlate significantly with ΔOC. No significant correlation was seen between ΔuNTx and change in prednisolone dosage. CONCLUSIONS: Decreased glucocorticoid dosage improved bone metabolic markers in RA, but disease activity, bisphosphonate therapy, and period of biologics therapy did not influence levels of bone metabolic markers. Decreasing glucocorticoid dosage appears important for improving bone metabolic marker profiles in patients with RA.

Perioperative haemostatic management of haemophilic mice using normal mouse plasma.

Intense haemostatic interventions are required to avoid bleeding complications when surgical procedures are performed on haemophilia patients. The objective of this study was to establish an appropriate protocol for perioperative haemostatic management of haemophilic mice. We assessed the prophylactic haemostatic effects of normal mouse plasma (NMP) on haemophilia B (HB) mice for both a skin flap procedure and a laparotomy. When 500 µL of NMP was administered to the mice, plasma factor IX (FIX:C) levels peaked at 15.1% immediately after intravenous (IV) administration, at 6.1% 2 h after intraperitoneal (IP) administration and at 2.7% 6 h after subcutaneous administration. Administering 500 µL of NMP via IP or IV 30 min in advance enabled the skin flap procedure to be performed safely without any complications. After the laparotomy procedure, several mice in the IP administration group exhibited lethal bleeding, but all mice survived in the IV administration group. Anti-mouse FIX inhibitors did not develop, even after repetitive administrations of NMP. However, human FIX concentrates, especially plasma-derived concentrates, elicited the anti-human FIX inhibitors. The results show that administering 500 µL of NMP via IV or IP 30 min in advance enables surgical procedures to be safely performed on HB mice, and that IV administration is more desirable than IP if the procedure requires opening of the abdominal wall.

TNF-α modulates expression of the circadian clock gene Per2 in rheumatoid synovial cells.

OBJECTIVES: To study the effect of tumour necrosis factor (TNF)-α, responsible for the inflammation and circadian rhythm of rheumatoid arthritis (RA), on the expression of circadian clock genes in primary cultured human rheumatoid synovial cells. METHOD: The expression of circadian clock genes, including circadian locomotor output cycles kaput (Clock), brain and muscle Arnt-like protein-1 (Bmal1), period (Per)1/2, and cryptochrome (Cry)1/2, and the proline and acidic amino acid-rich basic leucine zipper (PAR bZip) genes, a transcriptional activator of Per2, including D site of albumin promoter binding protein (Dbp), hepatic leukaemia factor (Hlf), and thyrotroph embryonic factor (Tef), and a transcriptional repressor of Per2, E4-binding protein 4 (E4bp4), in TNF-α-stimulated synovial cells was determined by real-time polymerase chain reaction (PCR). The D-box motifs in the Per2 promoter were mutated by site-directed mutagenesis, and the promoter activity of the Per2 gene was examined using the luciferase assay. RESULTS: TNF-α enhanced the mRNA expression of Bmal1 and Cry1 but did not affect that of Clock, Per1, or Cry2. However, TNF-α inhibited the mRNA expression of the Per2 gene, as well as Dbp, Hlf, and Tef, but enhanced the mRNA expression of E4bp4. Furthermore, TNF-α inhibited the transcriptional activity of the wild-type Per2 gene in a manner dependent on the D-box 1 and D-box 2 motifs in the Per2 promoter. CONCLUSIONS: TNF-α modulates the expression of the Per2 gene through the D-box binding proteins DBP, HLF, TEF, and E4BP4, in rheumatoid synovial cells, and thereby may contribute to the pathogenesis of RA.

Enzastaurin has anti-tumour effects in lung cancers with overexpressed JAK pathway molecules.

BACKGROUND: Enzastaurin, an oral serine-threonine kinase inhibitor, was initially developed as an ATP-competitive selective inhibitor against protein kinase Cß. However, the mechanism by which enzastaurin contributes to tumourigenesis remains unclear. METHODS: We analysed the anti-tumour effects of enzastaurin in 22 lung cancer cell lines to ascertain the potential for enzastaurin-based treatment of lung cancer. To identify molecules or signalling pathways associated with this sensitivity, we conducted a gene, receptor tyrosine kinases phosphorylation and microRNA expression profiling study on the same set of cell lines. RESULTS: We identified eight genes by pathway analysis of molecules having gene-drug sensitivity correlation, and used them to build a support vector machine algorithm model by which sensitive cell lines were distinguished from resistant cell lines. Pathway analysis revealed that the JAK/STAT signalling pathway was one of the main ones involved in sensitivity to enzastaurin. Overexpression of JAK1 was observed in the sensitive cells by western blotting. Simultaneous administration of enzastaurin and JAK inhibitor inhibited enzastaurin-induced cell growth-inhibitory effect. Furthermore, lentiviral-mediated JAK1-overexpressing cells were more sensitive to enzastaurin than control cells. CONCLUSION: Our results suggested that the JAK1 pathway may be used as a single predictive biomarker for enzastaurin treatment. The anti-tumour effect of enzastaurin should be evaluated in lung cancer with overexpressed JAK pathway molecules.

Cell sheet engineering: a unique nanotechnology for scaffold-free tissue reconstruction with clinical applications in regenerative medicine.

Cell sheet technology (CST) is based on the use of thermoresponsive polymers, poly(N-isopropylacrylamide) (PIPAAm). The surface of PIPAAms is formulated in such a way as to make its typical thickness <100 nm. In this review, we first focus on how the methods of PIPAAm-grafted surface preparations and functionalization are important to be able to harvest a functional cell sheet, to be further transplanted. Then, we present aspects of tissue mimics and three-dimensional reconstruction of a tissue in vitro. Finally, we give an overview of clinical applications and clinically relevant animal experimentations of the technology, such as cardiomyopathy, visual acuity, periodonty, oesophageal ulcerations and type 1 diabetes.

Incidence and risk factors of falling in ambulatory patients with rheumatoid arthritis: a prospective 1-year study.

UNLABELLED: A prospective 1-year study showed that fall incidence was 50% in women with rheumatoid arthritis. Multivariate analysis identified swollen joint count, use of antihypertensives or diuretics, one-leg standing time, and sway area measured by stabilometer as significant parameters associated with falls. INTRODUCTION: Patients with rheumatoid arthritis (RA) may be at increased risk of falling because they frequently experience muscle weakness and stiff or painful joints. The aim of this study was to use a prospective design to determine the incidence of falls and their risk factors in women with RA. METHODS: Eighty-four women aged 50 and over who had RA were enrolled. The mean age was 64.1 years. We evaluated postural stability, physical performance related to falls, disease activity, muscle volume, and bone density. The occurrence of falls was assessed every month for 1 year. Among 84 patients, 80 completed a 1-year observation. RESULTS: Forty patients (50.0%) reported one or more falls, and two of them (5.0%) had fractures during the follow-up period. The fall group had more swollen joints and took more antihypertensives and/or diuretics. The fall group also had lower postural stability and tended to have reduced physical performance. The one-leg standing time was shorter, and the step-up-and-down test score was lower in the fall group. The sway area was larger in the fall group. DISCUSSION: Multiple logistic regression analysis identified that number of swollen joints, use of antihypertensives or diuretics, shorter time standing on one foot, and the sway area were the most significant parameters associated with falls. CONCLUSION: We concluded that fall rates in RA patients were higher than in the general population and that balance impairment or side effects of drugs may play a role in increasing the risk of falls.

Measurement of human trabecular bone by novel ultrasonic bone densitometry based on fast and slow waves.

SUMMARY: Two longitudinal transmitted waves, fast and slow waves, were observed by employing a new quantitative ultrasound (QUS) method. The trabecular bone measurements generated by this method reflect three-dimensional structural information, and the new QUS parameters were able to identify vertebral fractures. INTRODUCTION: The aims were to identify new quantitative ultrasound (QUS) parameters that based on new QUS method reflecting not only bone volume but also the microstructures of trabecular bone ex vivo and to observe how much they predict fracture risk in vivo. METHODS: Ex vivo measurement: Three human femoral heads were used for the experiment. Attenuation of the slow wave, attenuation of the fast wave, speed of the slow wave, speed of the fast wave (SOFW), bone mass density of trabecular bone, and elastic modulus of the trabecular bone (EMTb) of each specimen were obtained using a new QUS method and compared with three-dimensional structural parameters measured by micro-computed tomography. In vivo measurement: Eighty-nine volunteers were enrolled, and the bone status in the distal radius was measured using a new QUS method. These parameters were compared with data evaluated by peripheral quantitative computed tomography and dual X-ray absorptiometry. RESULTS: Ex vivo measurement: SOFW and EMTb showed correlations with the parameter of trabecular anisotropy. In vivo measurement: The new QUS parameters were able to identify vertebral fractures. CONCLUSION: The newly developed QUS technique reflects the three-dimensional structure and is a promising method to evaluate fracture risk.

Sequential change in quality of life for patients with incident clinical fractures: a prospective study.

UNLABELLED: Health-related quality of life in elderly women with sustained incident fractures was assessed prospectively for 1 year, using the EuroQol standard. Loss of QOL was more severe in patients after hip or vertebral fractures than those with wrist fracture. QOL was not completely restored in patients suffering from hip fracture. INTRODUCTION: Osteoporosis-related fractures decrease mobility, social interaction, and emotional well-being. All of these characteristics determine health-related quality of life (HR-QOL). In this study, we assessed HR-QOL in elderly women following incident clinical fractures. METHODS: Thirty-seven patients with hip fractures (mean age 76.1 years), 35 with vertebral fractures (mean age 72.6 years), and 50 with wrist fractures (mean age 68.6 years) were enrolled. HR-QOL was prospectively measured using EuroQol (EQ-5D) before the fracture, 2 weeks, 3 months, 6 months, and 1 year after the fracture. RESULTS: During the observation period, reduction of EQ-5D values was greatest in the hip fracture group. In the wrist fracture group, EQ-5D values at 6 months after the fracture showed recovery; however, in the hip and vertebral fracture groups, recovery was significantly lower than before the fracture. One year after the fracture, EQ-5D values were not significantly different from prefracture values in the vertebral and wrist fracture groups, but remained significantly lower in the hip fracture group. CONCLUSIONS: Loss of QOL was more severe in patients after hip or vertebral fractures than in patients with wrist fracture. HR-QOL was not completely restored in patients suffering from hip fracture.

Recent trends in the incidence and lifetime risk of hip fracture in Tottori, Japan.

SUMMARY: Hip fracture incidence from 2004 to 2006 in the Tottori prefecture of Japan was investigated and compared with previously reported rates. The age- and gender-specific incidence of hip fracture in the Tottori prefecture has not plateaued, as has been reported for populations in Northern Europe or North America. INTRODUCTION: Recent data from Northern Europe and North America indicate that the incidence of hip fracture has plateaued, whereas most reports from Asia indicate that the incidence is increasing. The aims of this study were to investigate the recent incidence of hip fracture in the Tottori prefecture, Japan, and to compare it with previous reports. METHODS: All hip fractures in patients aged 35 years and older occurring between 2004 and 2006 were surveyed in all of the hospitals from the Tottori prefecture. The age- and gender-specific incidence rates were then calculated. Using these and previously reported data, the estimated number of hip fracture patients was determined using the age- and gender-specific incidence rates in each year from 1986 to 2006. RESULTS: The survey identified 851, 906, and 1,059 patients aged 35 years and older, in 2004, 2005, and 2006 respectively. The residual lifetime risk of hip fracture for individuals at 50 years of age was estimated to be 5.6% for men and 20.0% for women. The estimated number of patients from 1986 to 2006 showed a significant increase over time for both genders. CONCLUSIONS: The age- and gender-specific incidence of hip fracture in the Tottori prefecture, Japan has not plateaued for either gender.

High prevalence of vitamin K and D deficiency and decreased BMD in inflammatory bowel disease.

SUMMARY: Vitamin K and D deficiency and decreased bone mineral density (BMD) were highly prevalent in patients with inflammatory bowel disease (IBD), especially Crohn's disease (CD). Dietary intakes of these vitamins, however, were above the Japanese adequate intakes in IBD patients, suggesting that malabsorption is the basis for hypovitaminosis K and D and decreased BMD. INTRODUCTION: We have studied the possible involvement of vitamin K and D deficiency in the pathogenesis of decreased BMD in IBD. METHODS: Seventy patients with IBD were evaluated for their BMD; plasma levels of vitamin K; phylloquinone (PK), menaquinone-7 (MK-7), and 25OH-D; serum PTH, protein induced by vitamin K absence (PIVKA-II), and undercarboxylated osteocalcin (ucOC) levels; and their food intake. RESULTS: Compared with ulcerative colitis (UC) patients, CD patients had significantly lower plasma vitamin K and 25OH-D concentrations; significantly higher serum levels of PTH, PIVKA-II, and ucOC; and significantly lower BMD scores at almost all measurement sites. More IBD patients were vitamin K deficient in bone than in liver. Multiple regression analyses revealed that low plasma concentrations of vitamin K and 25OH-D were independent risk factors for low BMD and that they were associated with the patients' fat intake, but not with their intake of these vitamins. CONCLUSION: IBD patients have high prevalence of decreased BMD and vitamin K and D deficiency probably caused by malabsorption of these vitamins.

Nasal neuroendocrine carcinoma in a free-living Japanese raccoon dog (Nyctereutes procyonoides viverrinus).

Neuroendocrine carcinoma was diagnosed in the left nasal cavity of a free-living Japanese raccoon dog (Nyctereutes procyonoides viverrinus). Microscopically, the tumour consisted of sheets of anaplastic cells separated by narrow zones of fibrovascular stroma. The neoplastic cells had varying numbers of cytoplasmic granules stained by the Grimelius method. Immunohistochemically, the neoplastic cells were variably labelled for cytokeratin AE1/AE3, vimentin, chromogranin A and S-100. Ultrastructurally, some of the neoplastic cells had cytoplasmic membrane-bound dense-core granules of approximate diameter 140-240nm. The tumour had infiltrated the cerebrum and metastasized to the pituitary gland, mandibular and pulmonary lymph nodes, lungs, thyroid gland and adrenal glands.

Differential expression of MUC16 in human oral mucosal epithelium and cultivated epithelial sheets.

Cultivated oral mucosal epithelial sheet transplantation is a new surgical strategy to treat severe ocular surface disorders such as chemical burns, ocular cicatricial pemphigoid, and Stevens-Johnson syndrome. MUC16 is thought to be the most important membrane-associated mucin on the ocular surface because it forms a protective barrier on the epithelial cell surface. In this study, we studied MUC16 expression in mRNA and protein levels and compared the expression patterns between cultivated oral mucosal epithelial cell sheet and oral mucosal tissue. Specimens (5x5 mm) of oral mucosal tissue harvested from healthy volunteers were used. The oral mucosal epithelial cells were cultured on temperature-responsive culture dishes to generate stratified cell sheets. Cultivated oral mucosal epithelial cells formed three- to five-cell thick stratified sheets for 2 weeks. Scanning electron micrographs revealed that the apical surfaces of the oral mucosal tissue and the oral mucosal sheets were covered with dense microvilli/microplicae. Real-time PCR showed significantly more MUC16 transcripts in the cultivated oral mucosal sheets and corneal epithelial sheets than in the oral mucosal tissue (P=0.023 and 0.008, respectively, Mann-Whitney rank sum test). These findings were confirmed by immunohistochemical examination using an MUC16 antibody to the protein. MUC16 protein was localized to the apical cells of the oral mucosal sheets, but the human oral mucosal tissue did not express MUC16 protein in any cell layers. In this study, interestingly, the expression of membrane-associated mucin MUC16 differs between human oral mucosal epithelia and cultivated epithelial sheets. MUC16 expressed in the oral mucosal sheets may contribute to ocular surface reconstruction after oral mucosal sheet transplantation.

Cementum-periodontal ligament complex regeneration using the cell sheet technique.

BACKGROUND AND OBJECTIVE: In the present study we evaluated if a multilayered human periodontal ligament cell sheet could reconstruct the physiological architecture of a periodontal ligament-cementum complex. MATERIAL AND METHODS: Human periodontal ligament cells were isolated and then cultured in dishes coated with a temperature-responsive polymer to allow cell detachment as a cell sheet. In the control group, human periodontal ligament cells were cultured in Dulbecco's modified Eagle's minimal essential medium containing 10% fetal bovine serum and 1% antibiotics. In the experimental group, human periodontal ligament cells were cultured in Dulbecco's modified Eagle's minimal essential medium and osteodifferentiation medium containing dexamethasone, ascorbic acid and beta-glycerophosphate. After 3 wk, scanning electron microscopy was carried out, in addition to staining for alkaline phosphatase activity and for calcium (using the Von Kossa stain). Then human periodontal ligament cell sheets were multilayered and placed onto dentin blocks. The constructs were transplanted subcutaneously into the back of immunodeficient rats. At 1 and 6 wk after transplantation, the animals were killed. Demineralized tissue sections were stained using hematoxylin and eosin, and Azan, and then analyzed. RESULTS: After 3 wk of culture in osteodifferentiation medium, human periodontal ligament cells produced mineral-like nodules and also showed positive staining for alkaline phosphatase, calcium (Von Kossa) and mRNA expression of type I collagen. By contrast, in the control group only weak alkaline phosphatase staining was observed, the Von Kossa stain was negative and there was no mRNA expression of type I collagen. Six weeks after transplantation with human periodontal ligament cells cultured in osteodifferentiation medium, most of the dentin surfaces showed a newly immature cementum-like tissue formation and periodontal ligament with perpendicular orientation inserted into the newly deposited cementum-like tissue. CONCLUSION: This study suggests that the multilayered temperature-responsive culture system can be used as a novel strategy for periodontal regeneration. The human periodontal ligament cell sheet technique may be applicable for regeneration of the clinical periodontal ligament-cementum complex.

Mesothelial cells from tunica vaginalis, a practical source for mesothelial transplantation.

Transplantation of mesothelial cells is used to repair peritoneum that is damaged by surgery, peritonitis, and peritoneal dialysis. The largest obstacle for clinical application of mesothelial cell transplantation is the lack of a reliable source of mesothelial cells. So far, they are isolated from omentum, mesentery, parietal wall and ascites. Procedures used to obtain mesothelial cells from the omentum or mesentery are invasive, however, especially in pre-operative situations. Sufficient amounts of ascites for aspiration can not be obtained under physiological conditions. We have developed a novel method of isolating mesothelial cells from the tunica vaginalis. The tunica vaginalis originates from the peritoneum and descends into the scrotum along with the testis during fetal development. This region provides a source of mesothelial cells that is convenient to approach and free from abdominal complications. Transplantation of autologous mesothelial cells that were isolated from tunica vaginalis was effective in preventing post-operative adhesions. In this review, we summarize mesothelial cell transplantation trials and describe the method of isolating mesothelial cells form the tunica vaginalis. Mesothelial cell transplantation might be widely accepted for clinical use in the near future.

Vascularized Tissue-Engineered Model for Studying Drug Resistance in Neuroblastoma.

Neuroblastoma is a vascularized pediatric tumor derived from neural crest stem cells that displays vasculogenic mimicry and can express a number of stemness markers, such as SOX2 and NANOG. Tumor relapse is the major cause of succumbing to this disease, and properties attributed to cancer stem-like cells (CSLC), such as drug-resistance and cell plasticity, seem to be the key mechanisms. However, the lack of controllable models that recapitulate the features of human neuroblastoma limits our understanding of the process and impedes the development of new therapies. In response to these limitations, we engineered a perfusable, vascularized in vitro model of three-dimensional human neuroblastoma to study the effects of retinoid therapy on tumor vasculature and drug-resistance. METHODS: The in vitro model of neuroblastoma was generated using cell-sheet engineering and cultured in a perfusion bioreactor. Firstly, we stacked three cell sheets containing SKNBE(2) neuroblastoma cells and HUVEC. Then, a vascular bed made of fibrin, collagen I and HUVEC cells was placed onto a collagen-gel base with 8 microchannels. After gelling, the stacked cell sheets were placed on the vascular bed and cultured in the perfusion bioreactor (perfusion rate: 0.5 mL/min) for 4 days. Neuroblastoma models were treated with 10µM isotretionin in single daily doses for 5 days. RESULTS: The bioengineered model recapitulated vasculogenic mimicry (vessel-like structure formation and tumor-derived endothelial cells-TECs), and contained CSLC expressing SOX2 and NANOG. Treatment with Isotretinoin destabilized vascular networks but failed to target vasculogenic mimicry and augmented populations of CSLCs expressing high levels of SOX2. Our results suggest that CSLCs can transdifferentiate into drug resistant CD31+-TECs, and reveal the presence of an intermediate state STEC (stem tumor-derived endothelial cell) expressing both SOX2 and CD31. CONCLUSION: Our results reveal some roles of SOX2 in drug resistance and tumor relapse, and suggest that SOX2 could be a therapeutic target in neuroblastoma.

Characteristics of captive Japanese black bears (Ursus thibetanus japonicus) semen collected by electroejaculation with different voltages for stimulation and frozen-thawed under different conditions.

The Japanese black bear (Ursus thibetanus japonicus) is an endangered species in some areas of Japan, and semen collection and cryopreservation are important means to preserve genetic resources and prevent extinction. The aim of the present study was to improve the methods for electroejaculation and cryopreservation in these bears. We collected the semen from captive mature Japanese black bears during the mating season by the electroejaculation method using maximum stimulus voltages of 10 V (n=9) and 7 V (n=15), and compared the characteristics of fresh semen after collection. None of the variables examined (i.e. total sperm count, motility, viability, morphology, and rate of urine contamination) were statistically different between the two electro-stimulus voltages. After the semen obtained was cryopreserved, the effects of three different diluents (egg yolk-TRIS-citrate-glucose, egg yolk-TRIS-citrate-fructose, and egg yolk-TRIS-citrate-fructose-lactose-raffinose; n=10) and two different incubation times (1-1 and 3-0 h of cooling-glycerol equilibration times; n=12) on frozen-thawed spermatozoa. None of the variables examined (i.e. motility, viability and morphology) were statistically different among the three diluents and between the two incubation times. The results indicate that, in the collection and cryopreservation of Japanese black bear semen: (1) a maximum voltage of 7 V may be enough to obtain ejaculates; (2) the three diluents examined were useful; and (3) glycerol equilibration time may be omitted with prior cooling for 3h.

Effects of vincristine in combination with methotrexate and other antitumor agents in human acute lymphoblastic leukemia cells in culture.

The effects of vincristine (VCR) in combination with methotrexate (MTX) and other antitumor agents were evaluated by cell growth inhibition assay using a human acute lymphoblastic leukemia cell line (MOLT-3). The data were analyzed with the aid of an isobologram using the concept of an envelope of additivity (G. G. Steel and M. J. Peckman, Int. J. Radiat. Oncol., 5:85-91, 1979). Simultaneous exposure of VCR and MTX produced subadditive or mutually protective interactions. Sequential exposure to VCR first followed immediately by MTX produced similar interactions. When the interval of VCR exposure first and then MTX was increased from 0 to 3, 8, and 24 h, the inhibition of cell growth moved from protection and subadditivity to additivity only. The reversed order of exposure to the 2 drugs produced an entirely different picture. Thus, when the interval of MTX exposure first followed by VCR increased from 0 to 3, 8, and 24 h, the inhibitory effects of the combination changed progressively from the area of subadditivity to the area of supraadditivity. When these data were evaluated using median effect plot analyses (T-C. Chou and P. Talalay. In: New Avenues in Developmental Cancer Chemotherapy, pp. 36-64. Orlando, FL: Academic Press, 1987), strongly synergistic interaction of this sequence at space intervals was confirmed. These data show that the synergistic effects were produced only when MTX was followed 8 or 24 h later by VCR. Other schedules were only additive or even antagonistic. Simultaneous exposure of VCR with daunorubicin, 1-beta-D-arabinofuranosylcytosine, or bleomycin also had subadditive and protective effects. VCR, followed by daunorubicin with the interval of 24 h and vice versa, was again subadditive and protective. VCR, followed by 1-beta-D-arabinofuranosylcytosine with the interval of 24 h and vice versa, was again subadditive or additive only. Simultaneous and continuous exposures of VCR with vinblastine or L-asparaginase were only marginally supraadditive.