Fracture healing on non-union fracture model promoted by non-thermal atmospheric-pressure plasma

Non-thermal atmospheric-pressure plasma (NTAPP) is attracting widespread interest for use in medical applications. The tissue repair capacity of NTAPP has been reported in various fields; however, little is known about its effect on fracture healing. Non-union or delayed union after a fracture is a clinical challenge. In this study, we aimed to investigate how NTAPP irradiation promotes fracture healing in a non-union fracture model and its underlying mechanism, in vitro and in vivo. For the in vivo study, we created normal and non-union fracture models in LEW/SsNSlc rats to investigate the effects of NTAPP. To create a fracture, a transverse osteotomy was performed in the middle of the femoral shaft. To induce the non-union fracture model, the periosteum surrounding the fracture site was cauterized after a normal fracture model was created. The normal fracture model showed no significant difference in bone healing between the control and NTAPP-treated groups. The non-union fracture model demonstrated that the NTAPP-treated group showed consistent improvement in fracture healing. Histological and biomechanical assessments confirmed the fracture healing. The in vitro study using pre-osteoblastic MC3T3-E1 cells demonstrated that NTAPP irradiation under specific conditions did not reduce cell proliferation but did enhance osteoblastic differentiation. Overall, these results suggest that NTAPP is a novel approach to the treatment of bone fractures.

Comparison of cost, surgical time, and clinical results between arthroscopic transosseous rotator cuff repair with lateral cortical augmentation and arthroscopic transosseous equivalent suture bridge: A propensity score-matched analysis

BACKGROUND

To reduce the healthcare burden, the clinical results of arthroscopic rotator cuff repair and the cost of the implants used have recently been focused upon. This study compared implant cost, surgical time, short-term clinical results, and cuff repair integrity 2 years postoperatively between arthroscopic transosseous rotator cuff repair using lateral cortical augmentation (TOA) and arthroscopic transosseous-equivalent suture bridge (TOE).

METHODS

This study included 220 patients with rotator cuff repairs performed by a single surgeon between December 2013 and December 2018. Overall, 70 TOA and 68 TOE cases met the inclusion criteria. The same surgeon performed the procedures at two different hospitals, and the techniques differed between the facilities. A total of 42 TOA patients were matched with 42 TOE patients. The patients were matched using a propensity score analysis by gender, age, and cuff tear size. The minimum follow-up period was 2 years. Implant cost and surgical time were compared between the two methods. The range of motion, clinical outcomes, and visual analog scale were evaluated. Magnetic resonance imaging was performed to examine cuff repair integrity 2 years postoperatively.

RESULTS

The follow-up rate was 81% (112/138 patients). Implant cost was significantly lower with TOA ($1,396 vs. $2,165; p < 0.001) than with TOE. The average surgical time in the TOA method was significantly shorter than that in the TOE method (82 vs. 109 min; p = 0.001). At a minimum 2-year follow-up, the mean active elevation, abduction, and clinical outcomes improved with both methods, although no improvements in external and internal rotations were observed with either method. There were no significant differences in the postoperative variables and retear rate (TOA, 12%; TOE, 19%; p = 0.548) between the two methods.

CONCLUSIONS

TOA and TOE achieved comparable clinical results; however, TOA was more cost-effective and had a shorter surgical time than TOE.

LEVEL OF EVIDENCE

Level Ⅲ, retrospective matched control study.

Comparison of short-term clinical outcomes and radiographic changes in Grammont reverse shoulder arthroplasty between the French and Japanese populations: A propensity score-matched analysis

BACKGROUND

Although Grammont-style reverse total shoulder arthroplasty (RSA) showed excellent clinical results in Europe, its utility for Asian populations remains unclear. This study aimed to compare the French and Japanese populations in terms of range of motion (ROM), functional outcomes, and scapular notching rates in patients who underwent standard Grammont-style RSA. We hypothesized that RSA for the Japanese population may not provide as good ROM and functional results at the final follow-up as that for the French population.

METHODS

A total of 25 Japanese patients undergoing RSA were propensity score matched to 25 French patients undergoing RSA. The patients were matched for four different covariates using a propensity score analysis. The minimum follow-up period was 2 years. We investigated differences between the populations with respect to body size and shoulder joint ROM and Constant score (CS) measured preoperatively and at the final follow-up. Scapular notching was examined using radiographs at the final follow-up.

RESULTS

The average height and weight of the French and Japanese patients were 164 cm and 70 kg and 152 cm and 56 kg, respectively. Anterior elevation (AE), external rotation (ER) at the side, internal rotation (IR), and CS total changed from 101° to 145°, 17° to 15°, 4.5 points to 5.5 points, and 36 points to 72 points, respectively, in the French population and from 63° to 119°, 8.5° to 13°, 4.6 points to 4 points, and 28 points to 58 points, respectively, in the Japanese population. AE improved in both the groups; ER and IR remained unchanged before and after surgery. The frequency of scapular notching (>grade 1) was higher in the Japanese population (56%) than in the French population (20%) (p = 0.019).

CONCLUSIONS

Grammont-style RSA improved AE and CS in both the populations, but AE and CS were significantly higher in the French population than in the Japanese population at the final follow-up. Scapular notching frequently occurs in the Japanese population.

Impact of constrained humeral liner on impingement-free range of motion and impingement type in reverse shoulder arthroplasty using a computer simulation

BACKGROUND

Dislocation is a major complication of reverse total shoulder arthroplasty (RSA). The humeral liner may be changed to a constrained type when stability does not improve by increasing glenosphere size or lateralization with implants, and patients, particularly women with obesity, have risks of periprosthetic instability that may be secondary to hinge adduction on the thorax, but there are few reports on its impact on the range of motion (ROM). This study aimed to determine the influence of humeral liner constraint on impingement-free ROM and impingement type using an RSA computer simulation model.

METHODS

A virtual simulation model was created using 3D measurement software for conducting a simulation study. This study included 25 patients with rotator cuff tears and rotator cuff tear arthropathy. Impingement-free ROM and impingement patterns were measured during flexion, extension, abduction, adduction, external rotation, and internal rotation. Twenty-five cases with a total of 4 patterns of 2 multiplied by 2, making a total of 100 simulations: glenosphere (38 mm normal type vs. lateralized type) and humeral liner constraint (normal type vs. constrained type). There were 4 combinations: normal glenosphere and normal humeral liner, normal glenosphere and constrained humeral liner, lateralized glenosphere and normal humeral liner, and lateralized glenosphere and constrained humeral liner.

RESULTS

Significant differences were found in all impingement-free ROM in 1-way analysis of variance (abduction: P = .01, adduction: P < .01, flexion: P = .01, extension: P = .02, external rotation: P < .01, and internal rotation: P < .01). Tukey's post hoc tests showed that the impingement-free ROM was reduced during abduction, external rotation, and internal rotation with the combination of the normal glenosphere and constrained humeral liner compared with the other combinations, and improved by glenoid lateralization compared with the combination of the lateralized glenosphere and constrained humeral liner. In the impingement pattern, the Pearson χ2 test showed significantly greater proportion of impingement of the humeral liner into the superior part of the glenoid neck in abduction occurring in the combination of the normal glenosphere and constrained humeral liner group compared with the other groups (P < .01). Bonferroni post hoc tests revealed that the combination of the normal glenosphere and constrained humeral liner was significantly different from that of the lateralized glenosphere and constrained humeral liner (P < .01). Using constrained liners resulted in early impingement on the superior part of the glenoid neck in the normal glenosphere, whereas glenoid lateralization increased impingement-free ROM.

CONCLUSION

This RSA computer simulation model demonstrated that constrained humeral liners led to decreased impingement-free ROM. However, using the lateralized glenosphere improved abduction ROM.

Bone mineral density around cementless short stems after reverse shoulder arthroplasty: changes over time and its relationship to stem positioning

Background

There are numerous reports of bone adaptation observed on plain radiography studies after the use of cementless short stems in reverse shoulder arthroplasty. However, reports on changes in bone mineral density (BMD) around the stem using dual-energy X-ray absorptiometry (DEXA) are prominently absent. In the present study, we measured BMD around the stem using DEXA and investigated changes over time from postoperative year 1 to year 2. Additionally, the relationship between BMD changes, filling ratio, and stem alignment was examined.

Methods

Forty-seven patients with short cementless stems who could be assessed via DEXA at 1-2 years postoperatively were included. After dividing the zones around the stem into 5, the BMD in each zone was measured, in addition to BMD changes and amount of change from postoperative year 1 to year 2. The relationship between filling ratio and stem alignment on postoperative plain radiography was assessed.

Results

A significant decrease in BMD in zone 3 was observed between postoperative year 1 and year 2 (P = .02). Regarding filling ratio and stem alignment, a negative correlation between valgus stem alignment and BMD change observed in zone 1 (r = -0.470, P < .01). In addition, stem valgus greater than 6° correlated with a significant decrease in BMD in zone 1. (P = .01). No significant differences were found in the other zones. Furthermore, there was no correlation between filling ratio and BMD change.

Conclusion

In reverse shoulder arthroplasty cementless short stems, changes that that occurred between postoperative year 1 to year 2 demonstrated a decrease in BMD in zone 3. In addition, a decrease in BMD in zone 1 was observed with a stem alignment of valgus 6° or higher, suggesting that stem alignment within valgus 6° is required to prevent a decrease in BMD.

Reliability and validity of a new deltoid muscle area measurement method after reverse shoulder arthroplasty

Background

Accurate deltoid muscle assessment after reverse shoulder arthroplasty (RSA) is difficult using magnetic resonance imaging due to metal artifacts. We hypothesized that measuring the deltoid muscle area (DA) in the middle part of the deltoid's total length postoperatively would reduce metal artifacts and allow for an accurate assessment. This study aimed to assess the reliability and reproducibility of magnetic resonance imaging and evaluate its impact on postoperative outcomes.

Methods

The DA in the middle part of the muscle's total length was measured twice by four examiners using pre and postoperative magnetic resonance imaging in 60 patients who underwent RSA (22 men, 38 women; mean age: 77.4 years). The DA at the greater tuberosity was measured preoperatively, and its correlation with the middle part of the deltoid's total length was evaluated. The Constant-Murley Score was measured at 2 years postoperatively, and its correlation with the DA in the middle part of the deltoid's total length pre- and postoperatively was assessed.

Results

Intraclass correlation coefficients for intraobserver measurements of preoperative and postoperative DA in the middle part of the deltoid's total length were almost perfect, with mean values of 0.98 and 0.97, respectively. The intraclass correlation coefficients for interobserver reliability regarding the first and second DA measurements in the middle part of the deltoid's total length were 0.95 and 0.95 (preoperatively) and 0.89 and 0.90 (postoperatively). The Constant-Murley Score was assessed at 2 years postoperatively in 51 patients. Muscle strength was weakly and moderately correlated with preoperative DA (r = 0.33, P = .02) and postoperative DA (r = 0.49, P < .01), respectively.

Conclusion

DA measurement in the middle part of the deltoid's total length after RSA was not affected by metal artifacts and had excellent reproducibility. This measurement method positively correlated with postoperative muscle strength, suggesting its usefulness for predicting postoperative muscle strength.

Parathyroid Hormone Inhibits Fatty Infiltration and Muscle Atrophy After Rotator Cuff Tear by Browning of Fibroadipogenic Progenitors in a Rodent Model

BACKGROUND

Progressive fatty infiltration and muscle atrophy after rotator cuff tears lead to tendon repair failure and poor outcomes. Fibro-adipogenic progenitors (FAPs) are involved in fatty infiltration and muscle homeostasis of skeletal muscle. Inducing FAP differentiation into brown adipocyte-like "beige adipocytes" suppresses fatty infiltration and muscle atrophy.

HYPOTHESIS

Parathyroid hormone (PTH) suppresses fatty infiltration and muscle atrophy after rotator cuff tears in a rat model by browning of FAPs.

STUDY DESIGN

Controlled laboratory study.

METHODS

PTH was administered subcutaneously for 4 or 8 weeks to a rotator cuff tear model in rats. After treatment, fatty infiltration of supraspinatus muscles was assessed using Oil Red O staining and muscle atrophy using wet muscle weight and muscle fiber cross-sectional area. Costaining of platelet-derived growth factor receptor α (FAP marker) and uncoupling protein 1 (browning marker) was performed to confirm FAP browning by PTH. Mouse-isolated FAPs were cultured with PTH and evaluated for browning-related gene expression and adipogenic differentiation using BODIPY staining. Myogenic differentiation of C2C12 myoblasts was evaluated using coculture of PTH-treated browning FAPs with C2C12.

RESULTS

PTH inhibited fatty infiltration after rotator cuff tear at 8 weeks. Rotator cuff wet muscle loss of PTH-treated rats was inhibited at 4 and 8 weeks. Furthermore, PTH-treated rats demonstrated larger myofiber cross-sectional area than did untreated rats at 4 and 8 weeks. Costaining indicated colocalization of platelet-derived growth factor receptor α and uncoupling protein 1 and promoted PTH-induced FAP browning. PTH increased the expression of browning-related genes in FAPs and suppressed fat droplet accumulation in vitro. Coculture with PTH-treated FAPs promoted C2C12 cell differentiation into myotubes.

CONCLUSION

PTH induced FAP-derived beige adipocytes by upregulating browning-related gene expression, and the browning effect of PTH on FAPs inhibited fatty infiltration and muscle atrophy in the rat rotator cuff tear model. PTH might have potential as a therapeutic drug for fatty infiltration and muscle atrophy after rotator cuff tears.

CLINICAL RELEVANCE

PTH may expand treatment options for rotator cuff tears by reducing fatty infiltration and muscle atrophy after rotator cuff tears by browning of FAPs.

Assessment of Prevalence and Risk Factors for Central Sensitization Related to Shoulder Osteoarthritis and Rotator Cuff Tears Using the Central Sensitization Inventory: A Cross-Sectional Study in Shoulder Surgery Patients

Shoulder disorders occasionally cause intractable pain. Central sensitization (CS) may be involved in such pain. Identifying risk factors associated with CS is crucial for effective pain control. This study aimed to determine the effects of shoulder osteoarthritis and rotator cuff tears (RCT) on CS and associated factors. This study included patients evaluated for CS using the Central Sensitization Inventory (CSI) before surgery for shoulder osteoarthritis, RCT, or cuff tear arthropathy. Patients with a CSI score of 40 or higher were defined as having CS. The relationships between glenohumeral osteoarthritis (GHOA), RCT size, and CS were statistically analyzed. Multiple regression analysis was performed to examine the factors affecting CSI scores. Subjects included 167 patients: 131 patients had RCT without GHOA, 23 had GHOA with RCT, and 13 had GHOA without RCT. The GHOA group had a significantly higher CSI score (27.5 [10.8-40.5] vs. 18.0 [10.0-27.5]) and CS prevalence (27.8% vs. 8.4%) than the RCT without GHOA group. There was no significant correlation between RCT size and CSI scores. Multiple regression analysis showed that female sex, severe pain, and long pain duration were associated with higher CSI scores. Considering the risk factors for CS might be helpful in shoulder treatment.

Deep learning-based screening tool for rotator cuff tears on shoulder radiography

BACKGROUND

Early diagnosis of rotator cuff tears is essential for appropriate and timely treatment. Although radiography is the most used technique in clinical practice, it is difficult to accurately rule out rotator cuff tears as an initial imaging diagnostic modality. Deep learning-based artificial intelligence has recently been applied in medicine, especially diagnostic imaging. This study aimed to develop a deep learning algorithm as a screening tool for rotator cuff tears based on radiography.

METHODS

We used 2803 shoulder radiographs of the true anteroposterior view to develop the deep learning algorithm. Radiographs were labeled 0 and 1 as intact or low-grade partial-thickness rotator cuff tears and high-grade partial or full-thickness rotator cuff tears, respectively. The diagnosis of rotator cuff tears was determined based on arthroscopic findings. The diagnostic performance of the deep learning algorithm was assessed by calculating the area under the curve (AUC), sensitivity, negative predictive value (NPV), and negative likelihood ratio (LR-) of test datasets with a cutoff value of expected high sensitivity determination based on validation datasets. Furthermore, the diagnostic performance for each rotator cuff tear size was evaluated.

RESULTS

The AUC, sensitivity, NPV, and LR- with expected high sensitivity determination were 0.82, 84/92 (91.3%), 102/110 (92.7%), and 0.16, respectively. The sensitivity, NPV, and LR- for full-thickness rotator cuff tears were 69/73 (94.5%), 102/106 (96.2%), and 0.10, respectively, while the diagnostic performance for partial-thickness rotator cuff tears was low at 15/19 (78.9%), NPV of 102/106 (96.2%) and LR- of 0.39.

CONCLUSIONS

Our algorithm had a high diagnostic performance for full-thickness rotator cuff tears. The deep learning algorithm based on shoulder radiography helps screen rotator cuff tears by setting an appropriate cutoff value.

LEVEL OF EVIDENCE

Level III: Diagnostic Study.

Intra-articular fibromembranous septum after intra-articular distal radial fracture: Arthroscopic excision and factors associated with formation of the septum

BACKGROUND

Intra-articular fibromembranous septum in the radiocarpal joint can cause wrist contracture after distal radial fracture, but the mechanism underlying the formation of the septum is unknown. This study examined the clinical outcomes in patients treated with arthroscopic excision of the septum and the factors associated with formation of the septum in patients with and without a septum.

METHODS

Fifty-three patients (22 with septum and 31 without septum) treated for intra-articular distal radial fracture with arthroscopy using a volar locking plate and secondary removal of the plate were included. Clinical outcomes and radiological assessments were analyzed.

RESULTS

In patients with a septum, the range of wrist flexion and total wrist arc before the second operation were significantly more limited than in those without a septum (p < 0.01 and p = 0.03, respectively). The improvement rate (improvement in wrist arc divided by the wrist arc of the healthy side) after arthroscopic excision of the septum and plate removal was greater in patients with a septum than in those without a septum (6.1% vs. 2.0%, p = 0.08). The significant factors affecting formation of the septum were the residual articular gap and the height of the midradial ridge on computed tomography images.

CONCLUSIONS

Intra-articular fibromembranous septum after surgically treated intra-articular distal radial fracture affects limited range of motion and secondary arthroscopic excision of the septum improves the wrist range of motion. Anatomical reduction and maintenance of the articular fragment, as well as anatomical characteristics might be causes of septum formation.

Results of the 𝚵− atomic X-ray measurement in J-PARC E07

Ξ− atomic X-ray spectroscopy is one of the most useful methods for investigation of the Ξ-nucleus strong interaction. A serious problem in the measurement is the significant background coming from in-flight Ξ− decay. For the first Ξ− atomic X-ray spectroscopy experiment, a novel method of identifying stopped Ξ− events using nuclear emulsion was developed to reject background photons from in-flight Ξ− decay. We succeeded in reducing the background to 1/170 by this method employing coincidence measurements using the nuclear emulsion and X-ray detectors.

Endoscopic resection of tendon xanthoma in the elbow of a patient with cerebrotendinous xanthomatosis

We describe the case of a 44-year-old woman with cerebrotendinous xanthomatosis (CTX) who had a tendon xanthoma on the right olecranon. The patient successfully underwent endoscopic resection. There were no signs of recurrence on MRI 2 years postoperatively. There were no complications related to the surgery, and the patient is completely satisfied with the treatment outcomes. CTX, a genetic metabolic disorder, is associated with the development of tendon xanthomas. Endoscopic resection of tendon xanthoma in the elbow of patients with CTX is a less invasive method than open resection.

Observation of Coulomb-Assisted Nuclear Bound State of Ξ^{-}-^{14}N System

In an emulsion-counter hybrid experiment performed at J-PARC, a Ξ^{-} absorption event was observed which decayed into twin single-Λ hypernuclei. Kinematic calculations enabled a unique identification of the reaction process as Ξ^{-}+^{14}N→_{Λ}^{10}Be+_{Λ}^{5}He. For the binding energy of the Ξ^{-} hyperon in the Ξ^{-}-^{14}N system a value of 1.27±0.21  MeV was deduced. The energy level of Ξ^{-} is likely a nuclear 1p state which indicates a weak ΞN-ΛΛ coupling.

Downward Terrestrial Gamma-Ray Flash Observed in a Winter Thunderstorm

During a winter thunderstorm on 24 November 2017, a strong burst of gamma rays with energies up to ∼10  MeV was detected coincident with a lightning discharge, by scintillation detectors installed at the Kashiwazaki-Kariwa Nuclear Power Station at sea level in Japan. The burst had a subsecond duration, which is suggestive of photoneutron production. The leading part of the burst was resolved into four intense gamma-ray bunches, each coincident with a low-frequency radio pulse. These bunches were separated by 0.7-1.5 ms, with a duration of ≪1  ms each. Thus, the present burst may be considered as a "downward" terrestrial gamma-ray flash (TGF), which is analogous to upgoing TGFs observed from space. Although the scintillation detectors were heavily saturated by these bunches, the total dose associated with them was successfully measured by ionization chambers, employed by nine monitoring posts surrounding the power plant. From this information and Monte Carlo simulations, the present downward TGF is suggested to have taken place at an altitude of 2500±500  m, involving 8_{-4}^{+8}×10^{18} avalanche electrons with energies above 1 MeV. This number is comparable to those in upgoing TGFs.

Abstract P1-11-07: Risk analysis for chemotherapy induced nausea and vomiting (CINV) in patients receiving FEC100 treatment

BACKGROUND:

Anthracycline-containing regimens are standard treatment options in adjuvant and neoadjuvant chemotherapy in breast cancer. Chemotherapy-induced nausea and vomiting (CINV) is experienced frequently in patients receiving these regimens, but the risk factors for CINV are unknown.

OBJECTIVE:

The aim of this study was to investigate risk factors for CINV in anthracycline-containing regimens retrospectively.

METHODS:

Data were collected from the JONIE study, which was conducted in order to estimate the efficacy of zoledronic acid in a neoadjuvant setting from March 2010 to June 2012 (UMIN000003261). A total of 180 patients were recruited, and we used CINV data from the first cycle of FEC100 treatment and patient backgrounds. As the protocol regulation allowed the use of antiemetic drugs,in the first cycle of the FEC100 regimen, patients received various types of antiemetic agents, which we classified into four groups: Dexamethasone (DEX)+5-HT3 receptor antagonist (5-HT3)+neurokinin-1 receptor antagonist (NK1) (DEX+5-HT3+NK1) group; Dexamethasone (DEX)+5-HT3 receptor antagonist (5-HT3) (DEX+5HT3) group; Dexamethasone (DEX)+5-HT3 receptor antagonist (5-HT3)+dopamine receptor antagonist (DRA) (DEX+5HT3+DRA) group; and Dexamethasone (DEX)+5-HT3 receptor antagonist (5-HT3)+neurokinin-1 receptor antagonist (NK1)+ dopamine receptor antagonist (DRA) (DEX+5-HT3+NK1+DRA) group. Risk factors were selected from patient backgrounds and the combinations of antiemetic drugs. In patient backgrounds, the body mass index (BMI) was stratified into 3 categories: Less than 18.5 (underweight group); equal to or more than 18.5 but less than 25 (standard BMI group); and equal to or more than 25 (overweight group). The risks for CINV were analyzed by univariate and multivariate analyses. P values of less than 0.05 were defined as significant.

RESULTS:

In a univariate analysis of nausea, the body mass index (BMI) was the only significant factor (P&lt;0.05). On the other hand, BMI and the combination of antiemetic drugs were significant factors in vomiting. (P&lt;0.05 and 0.005, respectively). In a multivariate analysis of nausea, the P value for BMI was 0.02. The odds ratio for the underweight group was 7.745 (confidence interval: 2.171 to 27.634) compared with the standard BMI group. In a multivariate analysis of vomiting, BMI and the combination of antiemetic drugs were significant risk factors (P=0.025 and 0.023, respectively). The odds ratio for the underweight group was 3.481 (confidence interval: 1.183 to 10.241)compared with the standard BMI group. Furthermore, the odds ratios in the DEX+5-HT3+DRA and DEX+5HT3 groups were 5.005 (confidence interval: 1.543 to 16.239) and 4.178 (confidence interval: 1.428 to 12.222), respectively, compared with the DEX+5-HT3+NK1 group, which was consistent with the CINV guidelines in 2011.

CONCLUSIONS:

This study revealed that BMI was the most important risk factor for nausea, and that BMI and the combination of antiemetic drugs were risk factors for vomiting. Underweight-patients tend to have CINV in anthracycline-containing regimen. The DEX+5-HT3+NK1 group was the best antiemetic drug combination. These result show that following the CINV guideline treatment is mandatory in order to prevent CINV.

Citation Format: Hayashi M, Nakazawa K, Hasegawa Y, Horiguchi J, Miura D, Ishikawa T, Takao S, Kim SJ, Yamagami K, Miyashita M, Konishi M, Shigeoka Y, Suzuki M, Taguchi T, Kubota T, Tanino Y, Yamada K, Kimura K, Akazawa K, Kohno N. Risk analysis for chemotherapy induced nausea and vomiting (CINV) in patients receiving FEC100 treatment [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-11-07.

Spheroid culture enhances osteogenic potential of periodontal ligament mesenchymal stem cells

OBJECTIVE AND BACKGROUND

Human periodontal ligament mesenchymal stem cells (hPDLMSCs) are reported to be responsible for homeostasis and regeneration of periodontal tissue. Although hPDLMSCs are commonly cultured in monolayers, monolayer cultures have been reported as inferior to 3-dimensional cultures such as spheroids, which are spherical clusters of cells formed by self-assembly. The aim of this study was to examine the osteogenic phenotype of spheroids of hPDLMSCs, compared with monolayer cultures of hPDLMSC, in vitro and in vivo.

MATERIAL AND METHODS

Spheroids were formed using microwell chips that were tagged with polyethylene glycol. Mesenchymal stem cell (MSC) markers in hPDLMSC spheroids were examined by flow cytometer. Real-time polymerase chain reaction analysis was examined to measure the expressions of stemness markers and osteogenesis-related genes in monolayer and spheroid-cultured hPDLMSCs. Immunofluorescence analysis was performed to confirm protein expressions of stemness markers in PDLMSC spheroids. Nodule formation assay, alkaline phosphatase (ALP) activity assay and transplantation assay in a mouse calvarial defect model were performed to confirm the osteogenic potential of hPDLMSC spheroids. To elucidate the mechanism of spheroid culture enhanced osteogenesis in hPDLMSCs with osteoinductive medium (OIM), a small interfering RNA (siRNA) assay targeted with secreted frizzled-related protein 3 (SFRP3) was examined. The levels of SFRP3 expression in monolayer and spheroid-cultured hPDLMSCs with OIM were measured by real-time polymerase chain reaction and western blotting analysis. ALP gene expression and ALP activity were examined in SFRP3-deficient hPDLMSC spheroids.

RESULTS

The hPDLMSC spheroids expressed MSC markers, which were similar to hPDLMSCs grown in monolayer cultures. Intriguingly, the protein and mRNA expressions of transcription factors that regulate "stemness" were significantly increased in hPDLMSC spheroids, compared with hPDLMSCs in monolayer cultures. Nodule formation by hPDLMSCs was significantly increased in spheroid cultures grown with OIM, compared with monolayer-cultured hPDLMSCs. ALP activity and expression of osteogenesis-related genes were also significantly enhanced in hPDLMSC spheroids, compared with monolayer cultures. Treatment with hPDLMSC spheroids significantly enhanced new bone formation in a murine calvarial defect model, compared with hPDLMSCs in monolayer culture. Finally, to elucidate mechanisms by which spheroid culture enhances ALP activation in hPDLMSCs grown with OIM, an siRNA assay was used to manipulate expression of SFRP3, a Wnt signaling antagonist. Knockdown of SFRP3 suppressed ALP gene expression in hPDLMSCs grown in OIM; further, it suppressed ALP activity in spheroid culture. These data suggest that the enhancement of osteogenic potential in hPDLMSC spheroids is regulated through SFRP3-mediated ALP activation.

CONCLUSION

Spheroid cultures of hPDLMSCs may be a novel and useful tool in regenerative medicine.

Mass Preparation of Primary Porcine Hepatocytes and the Design of a Hybrid Artificial Liver Module using Spheroid Culture for a Clinical Trial

To isolate a large number of porcine hepatocytes, we originally developed a mass preparation method that combined the usual collagenase perfusion method of a whole liver with a collagenase redigestion method of tissue fragments after liver perfusion. Using a pig of 10kg, collagenase perfusion only resulted in a yield of 63 ± 78 x 108 total cells with a viability of 69.2 ± 25.3 %, but our combined method had a yield of 167 ± 31 x 108 total cells with a viability of 87.9 ± 4.4 % (mean ± SD). Also, the combined method was applied to two pigs of 10kg body weight at the same time, and isolated 387 ± 89 x 108 hepatocytes with a viability of 87.1 ± 6.9 % and a purity of 93.6 ± 2.8 % in 11 experiments.

We designed a large multi-capillary polyurethane foam (MC-PUF) packed-bed module containing 1 x 1010 porcine hepatocytes on a clinical trial scale. The porcine hepatocytes in the module formed spherical multicellular aggregates (spheroids) of 200 – 500 μm diameter. Most hepatocytes forming spheroids were viable judged by fluorescein diacetate and ethidium bromide staining. The activities of ammonia removal, albumin secretion and oxygen consumption of the large MC-PUF module were the same as for a small MC-PUF module containing 2 x 108 porcine hepatocytes, and were maintained for at least 9 days of culture. These results show that a large MC-PUF module is successfully scaled up 50 times.

In conclusion, we succeeded in developing a mass preparation method of porcine hepatocytes and a large hybrid artificial liver module on a clinical trial scale.

Development of a Hybrid Artificial Liver using a Polyurethane Foam/Hepatocyte-Spheroid Packed-Bed Module

Primary dog hepatocytes spontaneously formed spheroids in the pores of polyurethane foam (PUF) within 1–2 days of stationary culture. The spheroids, about 100–150 μm in diameter, partly attached to the surface and immobilized inside these pores.

The lidocaine disappearance rate decreased to about 4 μg/105 viable cells/day for 10 days, while in the PUF/spheroid culture the rate was maintained at almost the initial level of 8 μg/105 viable cells/day for 10 days. Then, two scales of PUF packed-bed modules were designed. A small module (PUF volume; 14.5 cm3) was used for in vitro culture to investigate optimum culture conditions, and a large module (PUF volume; 300 cm3) was designed for dog experiments. Hepatocytes inoculated in these modules also formed spheroids and maintained almost the same activity of albumin secretion rate (111 μg/cm3 PUF/day in the small module and 87.7 μg/cm3 PUF/day in the large module). These results indicate that the PUF packed-bed module containing hepatocyte-spheroids is promising as a hybrid artificial liver

The Efficacy of Nafamostat Mesilate on the Performance of a Hybrid-artificial Liver using a Polyurethane foam/porcine Hepatocyte Spheroid Culture System in Human Plasma

Nafamostat mesilate (FUT) is a protease inhibitor of complement activation. The present study investigates whether FUT protects porcine hepatocytes from being injured by human plasma in a multi-capillary polyurethane foam packed-bed culture system (MC-PUF) such as the hybrid-artificial liver (PUF-HAL). Human plasmas with 1 mM of added ammonia were perfused using a small-scale PUF-HAL with porcine hepatocytes. FUT was continuously infused (10 μ g/ml, 50 μ g/ml,). The ammonia detoxification was maintained in human plasma for 24 hours and for 48 hours with FUT which suppressed the rapid increase of asparaginic acid aminotransferase (AST) and alanine aminotransferase (ALT). After 60 hours of perfusion, hepatocyte spheroids completely collapsed in the human plasma, but a small amount of hepatocyte spheroid was maintained by FUT. The effect of FUT was slightly greater at 50 μ g/ml than at 10 μ g/ml. Our results suggest that FUT has protective effects against porcine hepatocytes in human plasma, and our PUF-HAL using porcine hepatocytes can function in human plasma for about 48 hours with FUT.

Conditions Required for a Hybrid Artificial Liver Support System using a PUF/Hepatocyte-Spheroid Packed-Bed Module and it's use in Dogs with Liver Failure

We studied the effects of a hybrid artificial liver support system we developed on dogs with hepatic failure. The system consisted of a multi-channel polyurethane foam packed-bed culture module, including primary dog hepatocyte spheroids.

Blood ammonia was well metabolized by 20 g hepatocytes, but the other functions such as glucose concentration, total bile acid concentration, and survival time required 30 g hepatocytes to improve conditions. We found that we should use a culture substratum that easily forms spheroids, and that an artificial liver module should be used as soon as possible after spheroid formation by hepatocytes in the module.

Formation of a Sheet-Shaped Organoid Using Rat Primary Hepatocytes for Long-Term Maintenance of Liver-Specific Functions

In recent years, use of hepatocyte aggregates has led to development of a hybrid artificial liver support system (HALSS) that has high performance. However, in general, their thickness is 100 μm or more, and generation of a dead cell layer due to oxygen exhaustion inside the aggregates has been a universal problem. The present study proposes a novel organoid culture method with better performance than previous organoid culture methods by forming a sheet-shaped organoid (organoid-sheet) with a thickness of approximately 100 μm. The cell number of the organoid-sheet was maintained at approximately 75% of the initial number at 4 days of culture. On the other hand, that of a cylindrical organoid (cylindroid), which formed inside of a plasma separation hollow fiber with 285 μm inner diameter in our previous study, decreased to approximately 50% within 2 days. The ammonia removal rate of the cells in the organoid-sheet was higher than that of the cells in the cylindroid on the first day, but it decreased during the culture time. At day 15, the rate was reduced by almost 50% with respect to the value on the first day. The cells in the cylindroid displayed a lower ammonia removal rate. A significant difference was not observed between the albumin synthesis rates of the two cultures on the first day. However, over a period of time the cells in the organoid-sheet showed a higher albumin synthesis rate than cells in the cylindroid. As this novel organoid maintains these functions for at least 1 month, it is expected to be applied for the development of a HALSS with higher performance.

Differentiation Effects by the Combination of Spheroid Formation and Sodium Butyrate Treatment in Human Hepatoblastoma Cell Line (Hep G2): A Possible Cell Source for Hybrid Artificial Liver

The aim of this study was to investigate the feasibility of human hepatoblastoma cell line (Hep G2), which differentiates by spheroid formation, and treatment with sodium butyrate (SB) as a cell source for hybrid artificial liver (HAL). Hep G2 spontaneously formed spheroids in polyurethane foam (PUF) within 3 days of culture and restored weak ammonia removal activity. Treatment with SB, which is a histone deacetylase inhibitor, further increased the ammonia removal activity of Hep G2 spheroids in a concentration-dependent manner. The activation of ornithine transcarbamylase—a urea cycle enzyme—was significantly related to the upregulation of ammonia removal by spheroid formation, but scarcely contributed to the further upregulation following SB treatment. In contrast with ammonia removal, treatment with SB reduced the albumin secretion of Hep G2 spheroids in a concentration-dependent manner. In the PUF-HAL module in a circulation culture, the ammonia removal rate and albumin secretion rate (per unit volume of the module) of Hep G2 spheroids treated with 5 mM SB were almost the same as those of primary porcine hepatocyte spheroids. These results suggest that simultaneous use of spheroid formation and SB treatment in Hep G2 is beneficial in enhancing the functions of human hepatocytes with potential applications in regenerative medicine and drug screening.

On-ground detection of an electron-positron annihilation line from thunderclouds

Thunderclouds can produce bremsstrahlung gamma-ray emission, and sometimes even positrons. At 00:27:00 (UT) on 13 January 2012, an intense burst of gamma rays from a thundercloud was detected by the GROWTH experiment, located in Japan, facing the Sea of Japan. The event started with a sharp gamma-ray flash with a duration of <300 ms coincident with an intracloud discharge, followed by a decaying longer gamma-ray emission lasting for ∼60 s. The spectrum of this prolonged emission reached ∼10 MeV, and contained a distinct line emission at 508±3(stat.)±5(sys.) keV, to be identified with an electron-positron annihilation line. The line was narrow within the instrumental energy resolution (∼80keV), and contained 520±50 photons which amounted to ∼10% of the total signal photons of 5340±190 detected over 0.1-10 MeV. As a result, the line equivalent width reached 280±40 keV, which implies a nontrivial result. The result suggests that a downward positron beam produced both the continuum and the line photons.

Mechanical and neural changes in plantar-flexor muscles after spinal cord injury in humans

STUDY DESIGN

Cross-sectional study.

OBJECTIVES

To determine the effect of injury duration on plantar-flexor elastic properties in individuals with chronic spinal cord injury (SCI) and spasticity.

SETTING

National Rehabilitation Center for Persons with Disabilities, Japan.

METHODS

A total of 16 chronic SCI patients (age, 33±9.3 years; injury localization, C6-T12; injury duration, 11-371 months) participated. Spasticity of the ankle plantar-flexors was assessed using the Modified Ashworth Scale (MAS). The calf circumference and muscle thickness of the medial gastrocnemius (MG), lateral gastrocnemius and soleus were assessed using tape measure and ultrasonography. In addition, the ankle was rotated from 10° plantar-flexion to 20° dorsiflexion at 5 deg s(-1) with a dynamometer, and the ankle angle and torque were recorded. After normalizing the data (the initial points of angle and torque were set to zero), we calculated the peak torque and energy. Furthermore, angle-torque data (before and after normalization) were fitted with a second- and fourth-order polynomial, and exponential (Sten-Knudsen) models, and stiffness indices (SISOP, SIFOP, SISK) and AngleSLACK (the angle at which plantar-flexor passive torque equals zero) were calculated. The stretch reflex gain and offset were determined from 0-10° dorsiflexion at 50, 90, 120 and 150 deg s(-1). After logarithmic transformation, Pearson's correlation coefficients were calculated.

RESULTS

MAS, calf circumference, MG thickness, peak torque and SIFOP significantly decreased with injury duration (r log-log=-0.63, -0.69, -0.63, -0.53 and -0.55, respectively, P<0.05). The peak torque and SIFOP maintained significant relationships even after excluding impacts from muscle morphology.

CONCLUSION

Plantar-flexor elasticity in chronic SCI patients decreased with increased injury duration.

Risk factors for early hemorrhagic complications after endovascular coiling of ruptured intracranial aneurysms

BACKGROUND AND PURPOSE

The risk factors of early hemorrhagic complications after endovascular coiling are not well-known. We identified the factors affecting early hemorrhagic complications, defined as any expansion or appearance of hemorrhage shown by head CT in the initial 48 hours after coiling.

MATERIALS AND METHODS

We retrospectively reviewed a series of 93 patients who underwent coiling for a ruptured saccular aneurysm between 2006 and 2012 at our hospital.

RESULTS

Five patients showed early hemorrhagic complications, and all involved an expansion of the existing intracerebral hematoma immediately after coiling. The associated risk factors were accompanying intracerebral hemorrhage at onset (P < .001), postoperative antiplatelet therapy (P < .001), and thromboembolic complications (P = .044). In the accompanying intracerebral hemorrhage group, the associated risk factors were postoperative antiplatelet therapy (P = .044) and earlier initiation of coiling (9.8 ± 6.5 versus 28.1 ± 24.0 hours, P = .023). Early hemorrhagic complications were significant risk factors for worse clinical outcome (modified Rankin Scale, 2.02 ± 2.21 versus 4.4 ± 2.30, P = .022). None of the 93 patients showed further hemorrhage after the initial 48 hours after coiling.

CONCLUSIONS

The accompanying intracerebral hemorrhage at onset, thromboembolic complications, postoperative antiplatelet therapy, and earlier initiation of coiling were the risk factors for early hemorrhagic complications.

Soft x-ray intensity profile measurements of electron cyclotron heated plasmas using semiconductor detector arrays in GAMMA 10 tandem mirror

Temporally and spatially resolved soft x-ray analyses of electron cyclotron heated plasmas are carried out by using semiconductor detector arrays in the GAMMA 10 tandem mirror. The detector array has 16-channel for the measurements of plasma x-ray profiles so as to make x-ray tomographic reconstructions. The characteristics of the detector array make it possible to obtain spatially resolved plasma electron temperatures down to a few tens eV and investigate various magnetohydrodynamic activities. High power electron cyclotron heating experiment for the central-cell region in GAMMA 10 has been started in order to reduce the electron drag by increasing the electron temperature.

Possible evidence for free precession of a strongly magnetized neutron star in the magnetar 4U 0142+61

Magnetars are a special type of neutron stars, considered to have extreme dipole magnetic fields reaching ∼ 10(11) T. The magnetar 4 U 0142+61, one of the prototypes of this class, was studied in broadband x rays (0.5-70 keV) with the Suzaku observatory. In hard x rays (15-40 keV), its 8.69 sec pulsations suffered slow phase modulations by ± 0.7 sec, with a period of ∼ 15 h. When this effect is interpreted as free precession of the neutron star, the object is inferred to deviate from spherical symmetry by ∼ 1.6 × 10(-4) in its moments of inertia. This deformation, when ascribed to magnetic pressure, suggests a strong toroidal magnetic field, ∼ 10(12) T, residing inside the object. This provides one of the first observational approaches towards toroidal magnetic fields of magnetars.

Self-organization of Ge(111)/Al/glass structures through layer exchange in metal-induced crystallization

Al-induced crystallization enabled the self-organization of high-quality Ge/Al/glass structures through layer exchange at a low temperature of 325 °C.

Glue embolization for gastroduodenal ulcer bleeding: contribution to hemodynamics and healing process

BACKGROUND

Although the morbidity of bowel ischemic events after glue embolization has been suggested, a causal relationship between glue and ischemia has not been clearly established.

PURPOSE

To evaluate the efficiency and safety of transcatheter arterial embolization with n-butyl cyanoacrylate (NBCA-TAE) for upper gastrointestinal hemorrhage (GIH).

MATERIAL AND METHODS

Between October 2006 and October 2012, 21 patients with upper GIH underwent NBCA-TAE, and endoscopic data were obtained within 30 days of follow-up. Shock index prior to and immediately after NBCA-TAE were compared to determine changes in hemodynamics. Days to Forrest type III, as assessed by follow-up endoscopy, was used as an indicator of the healing process. Other clinical outcomes included days for starting ingestion and for hospital discharge.

RESULTS

Sixteen gastric and five duodenal ulcers, classified into Forrest type I, were treated. Immediate hemostasis was achieved in all the patients, and no re-bleeding occurred within the follow-up period. Shock index significantly (P < 0.001) improved from before (0.99 ± 0.076) to immediately after NBCA-TAE (0.67 ± 0.038). Sequential mucosal healing processes were observed in all the patients, and the number of days to Forrest type III was 9.6 ± 7.1. The number of days for starting ingestion and hospital discharge was 9.0 ± 4.5 and 15 ± 7.7 days, respectively.

CONCLUSION

NBCA-TAE is an effective and safe method for the control of nonvariceal upper GIH, in terms of contribution to hemodynamics and healing process of the gastroduodenal mucosa.

Hardening and termination of long-duration γ rays detected prior to lightning

We report the first observation of 3-30 MeV prolonged gamma-ray emission that was abruptly terminated by lightning. The gamma-ray detection was made during winter thunderstorms on December 30, 2010, by the Gamma-Ray Observation of Winter Thunderclouds experiment carried out in a coastal area along the Sea of Japan. The gamma-ray flux lasted for less than 3 min, continuously hardening closer to the lightning occurrence. The hardening at energies of 3-10 MeV energies was most prominent. The gamma-ray flux abruptly ceased less than 800 ms before the lightning flash that occurred over 5 km away from the experimental site. In addition, we observed a clear difference in the duration of the 3-10 MeV gamma rays and those >10 MeV, suggesting that the area of >10 MeV gamma-ray emission is considerably smaller than that of the lower-energy gamma rays. This work may give a manifestation that a local region emitting prolonged gamma rays connects with a distant region to initiate lightning.

Formation of cylindrical multicellular aggregate (cylindroid) and expression of liver specific functions of primary rat hepatocytes

In our studies of the development of a hybrid artificial liver, we investigated the formation of cylindrical multicellular aggregate (cylindroid) of primary rat hepatocytes on a pressed sheet of polyurethane foam (pressed-PUF) as a culture substratum. Hepatocytes formed cylindroids by attaching to a pressed-PUF surface, peeling off from the surface and aggregating. The diameter and length of most cylindroids were approximately 200-500 mum and 500 mum-2 mm, respectively. The activities of liver specific functions (albumin secretion and ammonia metabolism) of hepatocyte cylindroids were equivalent to or higher than those of hepatocyte spheroids. These results suggest that hepatocyte cylindroids can maintain highly differentiated functions longer than hepatocyte spheroids, and that a PUF/cylindroid culture may be effective to develop of a hybrid artificial liver.

Formation of porcine hepatocyte spherical multicellular aggregates (spheroids) and analysis of drug metabolic functions

Porcine hepatocytes are used in the hybrid artificial liver support system that we are developing because of their high level of liver functions in vitro and because human hepatocytes can not be used in Japan for ethical reasons. Spherical multicellular aggregates or spheroids have been found to be effective in vitro for long-term maintenance of liver functions. Therefore, we formed spherical multicellular aggregates (spheroids) of primary porcine hepatocytes using a polyurethane foam (PUF) as a culture substratum and analyzed their drug metabolic functions in vitro. Primary porcine hepatocytes inoculated into the pores of a flat PUF plate (25 x 25 x 1 mm), spontaneously formed spheroids within the range of 100 to 150 mum in diameter 24 to 36 h after inoculation. The formed spheroids were attached to the bottom surface of the PUF pores, and their morphology and viability were maintained for more than 12 days. The P-450 activity in the spheroids of porcine hepatocytes was demonstrated by detecting production of monoethylglycinexylidide from lidocaine. In addition, the conjugation enzyme activity was demonstrated by detecting glucuronidation and sulfation of acetaminophen. These activities were maintained for 12 days at a level twice as high as in the monolayer culture. This result shows that the porcine hepatocyte spheroids formed by using PUF can maintain the drug metabolic functions important in a hybrid artificial liver device. Consequently, culturing porcine hepatocyte spheroids using PUF seems to be promising for development of a hybrid artificial liver.

Characterization of human-type monoclonal antibodies against reduced form of hemin binding protein 35 from Porphyromonas gingivalis

BACKGROUND AND OBJECTIVE

The gram-negative anaerobe Porphyromonas gingivalis has been implicated as an important pathogen in the development of adult periodontitis, and its colonization of subgingival sites is critical in the pathogenic process. We previously identified a 35 kDa surface protein (hemin binding protein 35; HBP35) from P. gingivalis that exhibited coaggregation activity, while additional analysis suggested that this protein possessed an ability to bind heme molecules. For development of passive immunotherapy for periodontal diseases, human-type monoclonal antibodies have been prepared using HBP35 as an antigen in TransChromo mice. In the present study, we focused on a single antibody, TCmAb-h13, which is known to inhibit heme binding to recombinant HBP35. The aim of our investigation was to clarify the redox-related function of HBP35 and consider the benefits of human-type monoclonal antibodies.

MATERIAL AND METHODS

To examine the antigen recognition capability of TCmAbs with immunoblotting and Biacore techniques, we used the native form as well as several Cys-to-Ser variants of recombinant HBP35.

RESULTS

We found that the redox state of recombinant HBP35 was dependent on two Cys residues, (48) C and (51) C, in the thioredoxin active center (WCGxCx). Furthermore, TCmAb-h13 recognized the reduced forms of recombinant HBP35, indicating its inhibitory effect on P. gingivalis growth.

CONCLUSION

Hemin binding protein 35 appears to be an important molecule involved in recognition of the redox state of environmental conditions. In addition, TCmAb-h13 had an inhibitory effect on heme binding to recombinant HBP35, thereby interfering with P. gingivalis growth.