Comparison of short-term outcomes of robotic and laparoscopic transabdominal peritoneal repair for unilateral inguinal hernia: a propensity-score matched analysis

PURPOSE

This study aimed to compare perioperative outcomes of robotic and laparoscopic transabdominal peritoneal repair (TAPP) for unilateral inguinal hernia.

METHODS

This single institutional retrospective cohort study used de-identified data of patients who underwent robotic TAPP (R-TAPP) or laparoscopic TAPP (L-TAPP) for unilateral inguinal hernia between January 1, 2016 and October 31, 2021. Two cohorts were propensity matched, and data were analyzed. The learning curve was evaluated in the R-TAPP group.

RESULTS

Among 938 patients analyzed, 704 were included. After propensity-score matching, 80 patients were included in each group. The difference in operative time between R-TAPP and L-TAPP groups was 10 min (99.5 and 89.5 min, p = 0.087); however, console/laparoscopic time was similar (67 and 66 min, p = 0.71). The dissection time for medial-type hernia in the R-TAPP group was marginally shorter than that in the L-TAPP group (17 and 27 min, p = 0.056); however, there was no difference for lateral-type hernia (38.5 and 40 min p = 0.37). Perioperative variables, including estimated blood loss, postoperative hospital stay, and postoperative pain, had no significant difference, and chronic pain, which needed medication or intervention, was not observed in each group. The number of cases needed to achieve plateau performance was 7-10 in the R-TAPP group.

CONCLUSION

This study suggests that R-TAPP was safely introduced, and its perioperative outcomes were not inferior to those of L-TAPP. A shorter dissection time for medial-type hernia might be due to the robot's advantages, and a fast-learning curve could help with the early standardization of the procedure.

POS0441 DEVELOPMENT OF RHEUMATOID ARTHRITIS AMONG ANTI-CITRULLINATED PROTEIN ANTIBODIES POSITIVE ASYMPTOMATIC INDIVIDUALS: A PROSPECTIVE OBSERVATIONAL STUDY

Background:

In the idividuals with genetic and enviromental risk factors, immune events at mucosal surfaces occur and may precede systemic autoimmunity. Anti-citrullinated protein antibodies (ACPA) are present in the serum for an average of 3-5 years prior to the onset of rheumatoid arthritis (RA) during an asymptomatic period. In ACPA-positivite individuals, the additional presence of RA-related risk factors appears to add significant power for the development of RA. To date, there have been few reports in which clinical courses of ACPA-positive asymptomatic individuals were investigated prospectively.

Objectives:

To observe the clinical time course of ACPA-positive healthy population for the development of RA.

Methods:

Healthy volunteers without joint pain or stiffness, who attended the comprehensive health screening of our hospital, were enrolled in this prospective observational study. The serum ACPA levels were quantified by Ig-G anti-cyclic citrullinated peptide enzyme-linked immunosorbent assay with levels > 4.4 U/mL considered positive. ACPA-positive subjects were followed by rheumatologists of our department clinically or a questionnaire sent by mail for screening to detect arthritis.

Results:

5,971 healthy individuals without joint symptons were included. Ninty-two (1.5%) were positive for ACPA. Of these, 19 (20.7%) developed RA and two were suspected as RA by mail questionnaire. Their average age were 58-years, and women were 68%. The average duration between the date of serum sampling and diagnosis was 10.7 months. ACPA-positive individuals who developed to RA had higher serum ACPA and Ig-M rheumatoid factor levels than ACPA-positive individuals who did not (P value by Mann-Whitney U test: 0.002, 0.005, respectively).

Conclusion:

Among ACPA-positive asymptomatic individuals, 20% developed RA. The higher titer of ACPA and Ig-M rheumatoid factor levels are risk factors for devoloping RA.

Disclosure of Interests:

None declared

Early detection of Niemann-pick disease type C with cataplexy and orexin levels: continuous observation with and without Miglustat

Study objectives

Niemann-Pick type C (NPC) is an autosomal recessive and congenital neurological disorder characterized by the accumulation of cholesterol and glycosphingolipids. Symptoms include hepatosplenomegaly, vertical supranuclear saccadic palsy, ataxia, dystonia, and dementia. Some cases frequently display narcolepsy-like symptoms, including cataplexy which was reported in 26% of all NPC patients and was more often recorded among late-infantile onset (50%) and juvenile onset (38%) patients. In this current study, we examined CSF orexin levels in the 10 patients of NPC with and without cataplexy, which supports previous findings.

Methods

Ten patients with NPC were included in the study (5 males and 5 females). NPC diagnosis was biochemically confirmed in all 10 patients, from which 8 patients with NPC1 gene were identified. We compared CSF orexin levels among NPC, narcoleptic and idiopathic hypersomnia patients.

Results

Six NPC patients with cataplexy had low or intermediate orexin levels. In 4 cases without cataplexy, their orexin levels were normal. In 5 cases with Miglustat treatment, their symptoms stabilized or improved. For cases without Miglustat treatment, their conditions worsened generally. The CSF orexin levels of NPC patients were significantly higher than those of patients with narcolepsy-cataplexy and lower than those of patients with idiopathic hypersomnia, which was considered as the control group with normal CSF orexin levels.

Discussion

Our study indicates that orexin level measurements can be an early alert of potential NPC. Low or intermediate orexin levels could further decrease due to reduction in the neuronal function in the orexin system, accelerating the patients’ NPC pathophysiology. However with Miglustat treatment, the orexin levels stabilized or improved, along with other general symptoms. Although the circuitry is unclear, this supports that orexin system is indeed involved in narcolepsy-cataplexy in NPC patients.

Conclusion

The NPC patients with cataplexy had low or intermediate orexin levels. In the cases without cataplexy, their orexin levels were normal. Our study suggests that orexin measurements can serve as an early alert for potential NPC; furthermore, they could be a marker of therapy monitoring during a treatment.

AB0904 PERSISTENCE AND REASONS FOR DISCONTINUATION OF DENOSUMAB IN PATIENTS WITH RHEUMATOID ARTHRITIS

Background:

Denosumab, a fully human monoclonal antibody to receptor activator of nuclear factor kappa B ligand, which inhibits osteoclast differentiation, activation and survival, not only increases bone mineral density but also inhibits the progression of bone erosion in patients with rheumatoid arthritis (RA)1-3). Therefore, denosumab have been preferably prescribed for patients with RA recently. The persistence with denosumab, which is administered subcutaneously once every 6 months, was reported higher than with oral bisphosphonates4), and in the prospective cohort studies, the persistence rate for one year was reported to be 82-95%5-6). However, there have been no report about the persistence in patients with RA treated with denosumab, moreover the reasons for discontinuation of denosumab.

Objectives:

The aims of this single center retrospective cohort study were 1) to assess the persistence with denosumab in a routine clinical setting and 2) to identify the reasons of discontinuation in patients with RA. And we also reviewed the clinical outcomes of osteonecrosis of the jaw in patients with RA during denosumab treatment.

Methods:

The present study is based on databases from our hospital, which include age, gender, date of injection of denosumab, as well as information on patients’ characteristics. Patients were included in this study when denosumab were newly started at our department during the period from June 1, 2013 and September 30, 2017. In this study, persistence was defined as patients with an interval between injections of no longer than 6 months plus 8 weeks. Patients were followed until censoring (death, transferring to another hospital) or the end of the study (August 3, 2018).

We investigated reasons for the discontinuation of denosumab. Major reasons for the discontinuation of denosumab were classified as adverse event, anxiety over adverse events, patient’s transfer or request, doctor’s careless lack of refilling an injection, and other reason.

We identified patients who had been diagnosed as osteonecrosis of the jaw, and demographic, pharmacological, and clinical data were collected from medical records.

Results:

One hundred and seventy-five patients were identified. Kaplan–Meier analysis showed a slow decline of persistence after initiating denosumab therapy, dropping to 80.4 and 61.9 % after 1 and 2 years of follow-up. When analyzing the reason of discontinuation as adverse events, the persistence rate of denosumab was at 89.4, and 79.4% at 1, and 2 years of follow-up, respectively.

During 2-year period, 72 patients discontinued denosumab. A total of 27 adverse events occurred, of which five events were osteonecrosis of the jaw. The other reasons for adverse event included death in four, fracture in three, and so on. Six patients discontinued due to anxiety over dental adverse event. Thirteen patients were in doctor’s careless lack of refilling an injection

All five patients who were diagnosed as osteonecrosis of the jaw had received the treatment with prednisolone, and four were treated with biologic drugs. All patients stopped denosumab and switched to other drugs including teriparatide. All patients underwent surgical curettages of necrotic bone and cured.

Conclusion:

Persistence of denosumab in patients with RA is comparable to that in postmenopausal women with osteoporosis. Dental screening and care should be important to continue denosumab treatment.

References:

[1]Cohen SB.Arthritis Rheum. 2008;58:1299–1309.

[2]Takeuchi T.Ann Rheum Dis. 2019;78:899–907.

[3]Ebina K.Osteoporos Int. 2018;29:1627–1636.

[4]Hadji P.Osteoporos Int. 2016;27:2967–2978.

[5]Silverman SL.Arch Osteoporos. 2018;13:85. doi:10.1007/s11657-018-0491-z

[6]Hadji P.Osteoporos Int. 2015;26:2479–2489.

Disclosure of Interests:

Shinichi Mizuki Speakers bureau: AbbVie, Asahi Kasei, Chugai, Eli Lilly, Janssen, Mitsubishi Tanabe, Ono, Tatsuya Kai: None declared, Koji Mishima: None declared, Hiroko Ikeuchi: None declared, Kensuke Oryoji: None declared

0757 Increasing Number of Cases Who Had Both Hypersomnolence Disorders and Developmental Disorders With Orexin Measurements

Introduction

Recently, attention has been paid to the relationship between developmental disorders such as attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD), and sleep disorders. We meet many developmental disorder patients who complaint hypersomnolence. Among these patients, cases with coexistence of central hypersomnia and developmental disorders, or developmental disorder alone were increased. Therefore, we first investigated patients with the complaint of hypersomnolence, who were also suspected developmental disorders. Furthermore, we have been measuring CSF orexin in 17 cases suspected of both disorders to investigate orexin levels of these patients.

Methods

86patients who complained of EDS with suspicion of developmental disorders had been examined. In order to diagnose hypersomnolence disorders, PSG and MSLT were performed. Psychological examinations were performed for diagnosing developmental disorders.We have been measuring for CSF orexin in 17 cases suspected both hypersomnolence and developmental disorders. We examined the onset of hypersomnolence and the clinical history of these ADHD or ASD cases for more details.

Results

In 86 examined cases, developmental disorders coexisted in 30 cases. Among 30 cases, ADHD were 18, ASD were 6 and both diagnosed were 6 cases. Among them, 20 cases diagnosed as having coexistence of hypersomnia (8: narcolepsy, 12: IHS) and developmental disorders (ADHD:12, ASD:4, ADHD/ASD:4). In 17 cases with orexin measurements, 10 cases coexisted ADHD and 4 cases coexisted ASD. Two cases diagnosed as both ADHD and ASD. In 10 ADHD cases, 3 cases had low orexin levels, and 7 cases had normal orexin levels. Other 7 ASD cases had normal orexin levels.

Conclusion

ADHD has a higher rate of central hypersomnia (12/18) compared with ASD and the rate of narcolepsy was also high (5/12). While patients in ASD was diagnosed as IHS (3/6), narcolepsy cases were not observed. It became clear that the majority of patients had developmental disorder or had a tendency for developmental disorder before the onset of hypersomnolence.Although it is possible that ADHD/ASD symptoms may be exacerbated by orexin dysfunctions, ADHD/ASD may not newly occur. There were cases with low orexin levels, but it seems that narcolepsy happened to coexist with developmental disorders.

Support

a

P13.01 TERTpromoter methylation is significantly associated withTERTupregulation and tumor progression in pituitary adenomas

BACKGROUND

Activation of telomerase plays a critical role in tumor development. Somatic alterations in the promoter of the telomerase reverse transcriptase (TERT) gene are a major mechanism of upregulating telomerase. Several mechanisms have been associated with TERT abnormalities, including TERT promoter mutations or methylation. Mutations in the TERT promoter have been observed in a subset of brain tumors, especially in adult gliomas. In pituitary adenomas (PAs), however, TERT abnormalities are not fully understood. The present study aimed to investigate not only mutational but also methylation status changes in the TERT promoter in PAs and to analyze their correlations with clinical variables.

MATERIAL AND METHODS

We retrospectively studied 70 PAs consisting of 53 primary and 17 recurrent samples. Clinical data, including age at surgery, sex, tumor size, tumor subtype, resection rate, presence or absence of postoperative irradiation, and progression-free survival (PFS), were obtained from medical records. First, we investigated TERT promoter hotspot mutations via Sanger sequencing. Next, we quantified the methylation status of the TERT promoter using methylation-sensitive high-resolution melting analysis (MS-HRM). Finally, we investigated TERT mRNA expression levels using real-time quantitative PCR. Fisher’s exact test was applied to evaluate the statistical significance between TERT promoter methylation status and tumor recurrence. PFS was calculated using Kaplan-Meier estimates and compared between methylated with ummethylated PAs with the log-rank test. The correlation between TERT promoter methylation status and mRNA levels was analyzed with the Mann-Whitney U-test. PFS was analyzed using multivariate analysis with the Cox proportional hazards model and included the following variables: age, sex, tumor size, tumor subtype, resection rate, radiation therapy, and methylation status.

RESULTS

TERT promoter hotspot mutations were not observed in any PA sample. Nineteen percent of PAs exhibitedTERT promoter methylation, which was significantly predominant in recurrent PA samples. PFS was significantly shorter in the methylated cases than in the unmethylated cases. Higher TERT expression levels were correlated with methylation status.

CONCLUSION

We found that TERT promoter methylation upregulated TERT expression and was associated with shorter PFS in PAs. Our results suggest thatTERT promoter methylation may be a potential biomarker for predicting tumor recurrence in PAs.

P14.113 The role of maintenance high-dose methotrexate chemotherapy in elderly primary CNS lymphoma patients with complete response to induction immunochemotherapy

BACKGROUND

The addition of high-dose methotrexate (HD-MTX)-based chemotherapy to whole brain irradiation (WBRT) has improved the prognosis of primary central nervous system lymphoma (PCNSL). However, the high neurotoxicity rates observed, especially in the elderly, raised interest in chemotherapy-only treatments. Withholding radiotherapy substantially decreases the risk of neurotoxicity, however, disease control may be compromised. Therefore, developing a novel treatment for the elderly PCNSL patients (ePCNSL) is crucial. In the elderly who cannot tolerate WBRT as a consolidation, maintenance treatment may serve as a feasible approach after an initial response. We treated ePCNSL with induction immunochemotherapy with rituximab (RIT) and HD-MTX, maintenance chemotherapy with HD-MTX and deferred WBRT. Here, we retrospectively investigated the prognosis for ePCNSL that became CR after the induction chemotherapy.

MATERIAL AND METHODS

Newly diagnosed ePCNSL (median age: 74 years) received biweekly RIT/ HD-MTX (375 mg/m2/dose; 3.5g/m2/dose) for 6 cycles (induction) followed by monthly RIT/MTX for 2 cycles (consolidation) and then were treated differently according to the radiological response. With CR patients, HD-MTX was continued with every 3 months (maintenance) for 2 years. Patients who did not obtain consent for maintenance therapy were followed up.

RESULTS

Of the 42 ePCNSL (median age 74 years), 26 had CR after induction and consolidation, of which 18 cases were carried out maintenance (M +) and 8 cases were followed up (M-). The median age was 74 and 76, respectively. Median progression-free survival (mPFS) was 73 months in the M+ group and 24.6 months in the M- group. Median overall survival (mOS) is 92.5 months versus 27.6 months, respectively. Both mPFS (P= 0.025) and mOS (P =0.0003) were significantly prolonged by maintenance therapy. In addition, ePCNSL with tumors involvement of deep brain structure had a poor prognosis.

CONCLUSION

It was suggested that maintenance treatment with HD-MTX may improve the prognosis for ePCNSL that reached complete response after induction therapy.

Evaluation of circadian phenotypes utilizing fibroblasts from patients with circadian rhythm sleep disorders

We evaluated the circadian phenotypes of patients with delayed sleep-wake phase disorder (DSWPD) and non-24-hour sleep-wake rhythm disorder (N24SWD), two different circadian rhythm sleep disorders (CRSDs) by measuring clock gene expression rhythms in fibroblast cells derived from individual patients. Bmal1-luciferase (Bmal1-luc) expression rhythms were measured in the primary fibroblast cells derived from skin biopsy samples of patients with DSWPD and N24SWD, as well as control subjects. The period length of the Bmal1-luc rhythm (in vitro period) was distributed normally and was 22.80±0.47 (mean±s.d.) h in control-derived fibroblasts. The in vitro periods in DSWPD-derived fibroblasts and N24SWD-derived fibroblasts were 22.67±0.67 h and 23.18±0.70 h, respectively. The N24SWD group showed a significantly longer in vitro period than did the control or DSWPD group. Furthermore, in vitro period was associated with response to chronotherapy in the N24SWD group. Longer in vitro periods were observed in the non-responders (mean±s.d.: 23.59±0.89 h) compared with the responders (mean±s.d.: 22.97±0.47 h) in the N24SWD group. Our results indicate that prolonged circadian periods contribute to the onset and poor treatment outcome of N24SWD. In vitro rhythm assays could be useful for predicting circadian phenotypes and clinical prognosis in patients with CRSDs.

A novel measurement method for the morphology of the mandibular ramus using homologous modelling

OBJECTIVES

It is important to assess the mandibular morphology when orthognathic surgery, especially mandibular ramus osteotomy, is performed. Several studies on three-dimensional (3D) facial asymmetry have reported differences in linear and angle measurements between the deviated and contralateral sides in asymmetric mandibles. However, methods used in these studies cannot analyse the 3D morphology of the ramus. In this study, we aimed to evaluate the differences in mandibular ramus between the deviated and contralateral sides in asymmetric mandibles using traditional measurements as well as 3D shape analysis.

METHODS

15 Japanese females with jaw deformities treated by orthodontic surgery were enrolled. 3D CT images were reconstructed, and 14 landmarks were identified on the model surface. Ten linear and four angle measurements were calculated using these landmarks. Homologous ramus models were constructed for each sample, and after converting all homologous models to the right side, 30 homologous models of the ramus were analysed using principal component analysis.

RESULTS

Firstly, eight principal components explained >80% of the total variance. Differences between the deviated and contralateral sides in measurements and scores of the eight principal components were tested. Significant difference at the 5% level between the deviated and contralateral sides was observed in five linear measurements, three angle measurements and the third principal component. The variance of the deviated side was significantly larger in the diameter between the mandibular notch and coronoid process, horizontal dilated angle of the mandibular ramus and vertical dilated angle of the mandibular ramus. The variance of the contralateral side was significantly larger in the height of mandibular ramus, height of posterior of mandibular ramus, condylar width, height of condylar head and mandibular angle. The squared multiple correlation coefficient adjusted for the degrees of freedom was 0.815. The third principal component showed the difference between the deviated and contralateral sides. Shape variation represented by the third principal component visually indicated that the contralateral side was larger and had inwardly directed coronoid process and the deviated side had a mandibular angle that was turned inwards to a greater extent.

CONCLUSIONS

In conclusion, we successfully created a homologous model of the mandibular ramus and demonstrated the effectiveness of this model in the 3D comparison of the ramus morphology between the contralateral and deviated sides in asymmetric mandibles.

Factors associated with an unfavourable outcome after Salter innominate osteotomy in patients with unilateral developmental dysplasia of the hip: does occult dysplasia of the contralateral hip affect the outcome?

Salter innominate osteotomy is an effective reconstructive procedure for the treatment of developmental dysplasia of the hip (DDH), but some children have a poor outcome at skeletal maturity. In order to investigate factors associated with an unfavourable outcome, we assessed the development of the contralateral hip. We retrospectively reviewed 46 patients who underwent a unilateral Salter osteotomy at between five and seven years of age, with a mean follow-up of 10.3 years (7 to 20). The patients were divided into three groups according to the centre-edge angle (CEA) of the contralateral hip at skeletal maturity: normal (> 25°, 22 patients), borderline (20° to 25°, 17 patients) and dysplastic (< 20°, 7 patients). The CEA of the affected hip was measured pre-operatively, at eight to nine years of age, at 11 to 12 years of age and at skeletal maturity. The CEA of the affected hip was significantly smaller in the borderline and dysplastic groups at 11 and 12 years of age (p = 0.012) and at skeletal maturity (p = 0.017) than in the normal group. Severin group III was seen in two (11.8%) and four hips (57.1%) of the borderline and dysplastic groups, respectively (p < 0.001). Limited individual development of the acetabulum was associated with an unfavourable outcome following Salter osteotomy.

Early and late fracture following extensive limb lengthening in patients with achondroplasia and hypochondroplasia

Two types of fracture, early and late, have been reported following limb lengthening in patients with achondroplasia (ACH) and hypochondroplasia (HCH). We reviewed 25 patients with these conditions who underwent 72 segmental limb lengthening procedures involving the femur and/or tibia, between 2003 and 2011. Gender, age at surgery, lengthened segment, body mass index, the shape of the callus, the amount and percentage of lengthening and the healing index were evaluated to determine predictive factors for the occurrence of early (within three weeks after removal of the fixation pins) and late fracture (> three weeks after removal of the pins). The Mann‑Whitney U test and Pearson's chi-squared test for univariate analysis and stepwise regression model for multivariate analysis were used to identify the predictive factor for each fracture. Only one patient (two tibiae) was excluded from the analysis due to excessively slow formation of the regenerate, which required supplementary measures. A total of 24 patients with 70 limbs were included in the study. There were 11 early fractures in eight patients. The shape of the callus (lateral or central callus) was the only statistical variable related to the occurrence of early fracture in univariate and multivariate analyses. Late fracture was observed in six limbs and the mean time between removal of the fixation pins and fracture was 18.3 weeks (3.3 to 38.4). Lengthening of the tibia, larger healing index, and lateral or central callus were related to the occurrence of a late fracture in univariate analysis. A multivariate analysis demonstrated that the shape of the callus was the strongest predictor for late fracture (odds ratio: 19.3, 95% confidence interval: 2.91 to 128). Lateral or central callus had a significantly larger risk of fracture than fusiform, cylindrical, or concave callus. Radiological monitoring of the shape of the callus during distraction is important to prevent early and late fracture of lengthened limbs in patients with ACH or HCH. In patients with thin callus formation, some measures to stimulate bone formation should be considered as early as possible.

Differences in the developmental origins of the periosteum may influence bone healing

BACKGROUND AND OBJECTIVE

The jaw bone, unlike most other bones, is derived from neural crest stem cells, so we hypothesized that it may have different characteristics to bones from other parts of the body, especially in the nature of its periosteum. The periosteum exhibits osteogenic potential and has received considerable attention as a grafting material for the repair of bone and joint defects.

MATERIAL AND METHODS

Gene expression profiles of jaw bone and periosteum were evaluated by DNA microarray and real-time polymerase chain reaction. Furthermore, we perforated an area 2 mm in diameter on mouse frontal and parietal bones. Bone regeneration of these calvarial defects was evaluated using microcomputed tomography and histological analysis.

RESULTS

The DNA microarray data revealed close homology between the gene expression profiles within the ilium and femur. The gene expression of Wnt-1, SOX10, nestin, and musashi-1 were significantly higher in the jaw bone than in other locations. Microcomputed tomography and histological analysis revealed that the jaw bone had superior bone regenerative abilities than other bones.

CONCLUSION

Jaw bone periosteum exhibits a unique gene expression profile that is associated with neural crest cells and has a positive influence on bone regeneration when used as a graft material to repair bone defects. A full investigation of the biological and mechanical properties of jaw bone as an alternative graft material for jaw reconstructive surgery is recommended.

Effect of ADAMTS-13 on cerebrovascular microthrombosis and neuronal injury after experimental subarachnoid hemorrhage

BACKGROUND

Microthrombosis and reactive inflammation contribute to neuronal injury after subarachnoid hemorrhage (SAH). ADAMTS-13 cleaves von Willebrand factor multimers, and inhibits thrombus formation and, seemingly, inflammatory reactions.

OBJECTIVE

To investigate the effect of ADAMTS-13 in experimental SAH.

METHODS

A total of 100 male C57/BL6 mice were randomly assigned to four groups: sham (n = 15), SAH (n = 27), vehicle (n = 25), and ADAMTS-13 (n = 23; 100 μL per 10 g of body weight of 100 μg of ADAMTS-13 per 1 mL of 0.9% NaCl; 20 min after SAH). Neurologic performance was assessed on days 1 and 2 after SAH. Animals were killed on day 2. The amounts of subarachnoid blood, microthrombi, apoptosis and degenerative neurons were compared. The degree of neuronal inflammation and vasospasm was also compared. In five mice each (SAH and ADAMTS-13 groups), bleeding time was assessed 2 h after SAH.

RESULTS

Systemic administration of ADAMTS-13 achieved significant amelioration of microthrombosis and improvement in neurologic performance. ADAMTS-13 reduced the amount of apoptotic and degenerative neurons. A tendency for decreased neuronal inflammation was observed. ADAMTS-13 did not show any significant effect on vasospasm. The degree of systemic inflammation was not changed by ADAMTS-13 administration. ADAMTS-13 neither increased the amount of subarachnoid blood nor prolonged the bleeding time.

CONCLUSIONS

ADAMTS-13 may reduce neuronal injury after SAH by reducing microthrombosis formation and neuronal inflammation, thereby providing a new option for mitigating the severity of neuronal injury after SAH.

Biodistribution of locally or systemically transplantedosteoblast-like cells

Objectives

In order to ensure safety of the cell-based therapy for bone regeneration, we examined in vivo biodistribution of locally or systemically transplanted osteoblast-like cells generated from bone marrow (BM) derived mononuclear cells.

Methods

BM cells obtained from a total of 13 Sprague-Dawley (SD) green fluorescent protein transgenic (GFP-Tg) rats were culture-expanded in an osteogenic differentiation medium for three weeks. Osteoblast-like cells were then locally transplanted with collagen scaffolds to the rat model of segmental bone defect. Donor cells were also intravenously infused to the normal Sprague-Dawley (SD) rats for systemic biodistribution. The flow cytometric and histological analyses were performed for cellular tracking after transplantation.

Results

Locally transplanted donor cells remained within the vicinity of the transplantation site without migrating to other organs. Systemically administered large amounts of osteoblast-like cells were cleared from various organ tissues within three days of transplantation and did not show any adverse effects in the transplanted rats.

Conclusions

We demonstrated a precise assessment of donor cell biodistribution that further augments prospective utility of regenerative cell therapy.

Lin28a is a putative factor in regulating cancer stem cell-like properties in side population cells of oral squamous cell carcinoma

Cancer stem cells (CSCs) are among the target cells of cancer therapy because they are uniquely involved in both cancer progression and sensitivity to chemotherapeutic agents. We identified side population (SP) cells, which are known to be an enriched population of CSC, in five oral squamous cell carcinoma (OSCC) cells (SCC9, SCC25, TOSCC7, TOSCC17, and TOSCC23). The percentages of SP cells ranged from 0% to 3.3%, with TOSCC23 cells showing the highest percentages of SP cells (3.3% of the total cell population). The SP cells isolated from TOSCC23 cells also showed greater cell proliferation and invasion compared to non-SP (MP) cells. Therefore, our initial findings suggested that SP cells were enriched for CSC-like cells. Furthermore, DNA microarray analysis revealed that the expression of cell proliferation-related and anti-apoptotic genes was greater in SP cells compared to MP cells. We focused on Lin28a, which showed the highest expression (approximately 22-fold) among the upregulated genes. The overexpression of Lin28a in TOSCC23 cells increased their proliferation, colony formation, and invasion. These findings suggest that Lin28a is an appropriate CSC target molecule for OSCC treatment.

A new method for determining the optimal CT threshold for extracting the upper airway

OBJECTIVES

The purpose of this study was to evaluate the optimal upper threshold levels of a number of individuals and determine the most suitable upper threshold.

METHODS

A phantom model and ten patients were used in this study. The phantom was made of acrylic resin and urethane resin and had nine pillar-shaped air spaces. The subjects were ten female patients with jaw deformities who were not affected by respiratory disease. The optimal threshold levels were determined using the "calculation of CT value disparities" (CCTD) technique, which we devised. In other words, the mean CT values along two lines (air space and soft tissue) were calculated and the optimal threshold level was determined as the level that produced the maximum difference between the CT values measured inside and outside of the air-space border.

RESULTS

The optimal upper threshold levels of the nine phantom holes calculated using the CCTD technique in the front-on standing position and side-on standing position were -434 HU and -456 HU, respectively. The optimal upper threshold level of the ten patients calculated using the CCTD technique was -472 HU. The true threshold level of each patient was defined as the optimal threshold level calculated using the CCTD technique. The mean threshold level was defined as -472 HU. The absolute differences between the volume measurements obtained with these two measures were considered. Therefore, the no error values were -460 HU and -470 HU.

CONCLUSIONS

We consider that the most suitable upper threshold level for extracting the airway is from -460 HU to -470 HU.

Novel Compound Heterozygous Mutations in the Cathepsin K Gene in Japanese Female Siblings with Pyknodysostosis

We report on female siblings with pyknodysostosis who showed common clinical and radiographic features including disproportionate short stature, dental abnormalities, increased bone density, open fontanelle, and acroosteolysis. Sequence analysis of the cathepsin K (CTSK) gene demonstrated compound heterozygous mutations (935 C>T, A277V and 489 G>C, R122P) in the affected siblings and a heterozygous mutation in their parents. The former missense mutation has previously been reported in 6 unrelated patients, and the latter seemed to be a novel mutation. Atomic model assessment of the CTSK gene revealed that the R122P mutant could disrupt hydrogen bonds binding with chondroitin 4-sulfate leading to a decrease in the collagen-degrading activity of cathepsin K.