Refractive Index Measurement Using SOI Photodiode with SP Antenna toward SOI CMOS-Compatible Integrated Optical Biosensor

This paper proposes a new optical biosensor composed of a silicon-on-insulator (SOI) p-n junction photodiode (PD) with a surface plasmon (SP) antenna. When the phase-matching condition between two lateral wavelengths of the diffracted light from the SP antenna and the waveguiding mode in the SOI PD is satisfied, we observe sharp peaks in the spectroscopic light sensitivity. Since the peak wavelength depends on the RI change around the SP antenna corresponding to the phase-matching condition, the SOI PDs with an SP antenna can be applied to the optical biosensor. The RI detection limit is evaluated in the measurements with bulk solutions, and 1.11 × 10^-5 RIU (refractive index unit) can be obtained, which is comparable to that of a surface plasmon resonance (SPR) sensor, which is well known as a representative optical biosensor. In addition, the response for intermolecular bonds is estimated by the electromagnetic simulations using the finite-difference time-domain (FDTD) method to clarify its ability to detect biomolecular interactions. The results of this paper will provide new ground for high-throughput label-free biosensing, since a large number of SOI PDs with an SP antenna can be easily integrated on a single chip via an SOI complementary metal-oxide-semiconductor (CMOS) fabrication process.

Utility of periodic medical questionnaires and examinations for immune-related adverse event screening: A prospective observational study

Background

Immune checkpoint inhibitors (ICIs) are associated with immune-related adverse events (irAEs) specific to the immunity-boosting activity of the drugs and may necessitate discontinuation of treatment depending on their severity. IrAEs may be difficult to diagnose in their early stages as they can occur in any organ. The present, prospective, observational study is the first to attempt to assess the utility of periodic medical questionnaires and laboratory, radiological, and physiological examinations in diagnosing irAEs.

Methods

We analyzed 51 patients who received immunotherapy for metastatic renal or urothelial carcinoma at Tokyo Metropolitan Tama Medical Center between 2016 and 2020. A medical questionnaire consisting of 41 questions and laboratory tests were administered to the patients on the day of each ICI administration and 1 week afterwards. A significant complaint was defined as a complaint not addressed in the questionnaire immediately prior to the first ICI administration.

Results

Fifty-one patients with metastatic renal or urothelial carcinoma were enrolled. The mean age was 72.1 years (range: 54–88 years). The male: female ratio was 32: 19. Of the total cohort, 26 (51%) patients had renal carcinoma, and 25 (49%) had urothelial carcinoma. The median follow-up time was 2.6 (range: 0.4–40.7) months. Thirty-three patients (65%) experienced irAEs.

Conclusions

In our cohort, periodic medical questionnaires and examinations were effective for early diagnosis and prompt treatment of irAEs. Although periodic examinations led to a high irAE diagnosis rate, the attendant medical cost was high. Further study is needed to find ways of addressing this issue.

Kdm5a promotes B cell activation in systemic lupus erythematosus via downregulation of A20 by histone modification

Systemic lupus erythematosus (SLE) is a classic autoimmune connective tissue disease, which leads to multiple organ system injury. Tumor necrosis factor-induced protein 3 (TNFAIP3), generally called A20, has been documented to go together with the development of SLE. However, the role and mechanism of A20 in the progression of SLE are still unrevealed. In our study, A20 was downregulated in B cells from SLE patients and B cell responsiveness was significantly elevated in SLE patients. Overexpression of A20 restrained the proliferation and induced the apoptosis of B cells. Additionally, trimethylation of histone H3 Lysine 4 (H3K4me3) was decreased in the A20 promoter of SLE B cells. Lysine demethylase 5 A (Kdm5a) was significantly increased in B cells from SLE patients and negatively correlated with A20 expression. Further, Kdm5a knockdown increased the H3K4me3 level and A20 expression. More importantly, Kdm5a promoted the proliferation and inhibited the apoptosis of B cells in SLE via downregulation of A20. In general, Kdm5a promoted the proliferation and inhibited the apoptosis of B cells in SLE via downregulation of A20 by decreasing H3K4me3 enrichment level in the A20 promoter, suggesting a novel mechanism underlying SLE progression, and providing a promising therapeutic target for SLE. AVAILABILITY OF DATA AND MATERIALS: All data generated or analyzed during this study are included in this published article and its additional files.

Cerebral metastasis during remission after immunotherapy for metastatic urothelial carcinoma: A case report

Central nervous system (CNS) metastasis of urothelial carcinoma (UC) is rare. Immune checkpoint inhibitors, which were developed for the treatment of patients with advanced cancer, have limited efficacy against CNS metastases due to the unique immune microenvironment of the brain. The brain is an immune-privileged organ and is protected by the blood-brain barrier. However, the management of CNS metastases of UC is crucial to improving the prognosis. The present report describes two cases of cerebral metastasis occurring in the context of systemic disease control using immunotherapy. To the best of our knowledge, the present report is the first to describe a CNS metastasis during remission induced by immunotherapy.

Novel operative technique of advancement urethral meatoplasty utilizing buccal mucosa for Vulvar Paget's disease with urethral invasion: two case reports

BACKGROUND

Vulvar Paget's disease (VPD) is a rare malignant disorder originating in the external genitalia. It occasionally invades into urethral or vaginal mucosa of female, making surgical treatment more complicating. In case of urethral invasion of Paget's cells, systematic mapping biopsy of urethral mucosa is the standard of care to determine the range of surgical resection. Resection of urethral mucosa and simple skin grafting often result in urethral stricture after surgery, which severely deteriorates patient's quality of life.

CASE PRESENTATION

We applied a new technique of advancement urethral meatoplasty using buccal mucosa, in two Japanese cases of VPD with urethral invasion. After broad resection of vulvar skin together with the urethral mucosa, buccal mucosa was implanted between advanced urethral mucosa and skin graft. In both cases, we could prevent urethral stricture one year and two years after surgery, respectively.

CONCLUSION

This technique prevented urethral stricture after surgery and could be a useful technique as part of urethroplasty for VPD.

Submucosal urothelial bladder cancer: A case report

Bladder tumors can be broadly divided into those of epithelial or mesodermal origin. Furthermore, 90% of bladder tumors arise from the epithelium of the bladder, and most cases of bladder cancer are histologically urothelial carcinomas. Mesodermal tumors are exceptionally rare and often benign. Of the mesenchymal tumors of the bladder, leiomyomas are the most common, and their prognosis depends on their histology. The present report describes a case of submucosal urothelial cancer in a patient with no past history of bladder cancer. To the best of our knowledge, there are no previous reports of urothelial cancer occurring in the submucosa. The present report was the first to document a case of submucosal urothelial cancer, whose diagnosis was made possible only by transurethral resection of bladder tumor. Although the precise pathomechanism of the present case was unclear, two hypotheses were considered. First, the urothelial cancer developed within a diverticulum, then the entrance of the diverticulum closed, sealing in the cancer. Second, the bladder cancer stemmed from aberrant urothelium in the submucosal tissue. If submucosal urothelial bladder carcinoma develops within the diverticular environment, its prognosis can be as poor as that of invasive bladder cancer due to the features of the diverticular environment. Even in a patient with a submucosal bladder tumor but no previous history of bladder cancer, bladder cancer should be considered in the differential diagnosis.

THU0231 IL-2 DRIVES THE CONVERSION OF T FOLLICULAR HELPER TO T FOLLICULAR REGULATORY CELLS THROUGH EPIGENETIC MODIFICATION IN SYSTEMIC LUPUS ERYTHEMATOSUS

Background:

Systemic lupus erythematosus (SLE) is a complex polygenic autoimmune disease characterized by immune-system aberrations. Among several types of immune cells, T follicular helper (Tfh) cells promote autoantibody production, whereas T follicular regulatory (Tfr) cells suppress Tfh-mediated antibody responses.(1)

Objectives:

To identify the characteristics of Tfr cells and to elucidate the mechanisms of conversion of Tfh cells to Tfr cells, we probed the phenotype of T helper cells in patients with SLE and underlying epigenetic modifications by cytokine-induced signal transducer and activators of transcription (STAT) family factors.

Methods:

Peripheral blood mononuclear cells from SLE patients (n=44) and healthy donors (HD; n=26) were analyzed by flow cytometry. Memory Tfh cells were sorted and cultured under stimulation with T cell receptor and various cytokines. Expression of characteristic markers and phosphorylation of STATs (p-STATs) were analyzed by flow cytometry and quantitation PCR. Histone modifications were evaluated by chromatin immunoprecipitation.

Results:

The proportion of CXCR5+FoxP3+Tfr cells in CD4+T cells tended to increase (2.1% vs 1.7%, p=0.17); however, that of CD4+CD45RA-FoxP3hiactivated Tfr cells in Tfr cells was decreased (4.8% vs 7.1%, p<0.05), while CD4+CD45RA-FoxP3lownon-suppressive Tfr cells was increased (50.1% vs 38.2%, p<0.01) in SLE compared to HD. The percentage of PD-1hiactivated Tfh cells was significantly higher in SLE compared to HD (15.7% vs 5.9%, p<0.01). Furthermore, active patients had a higher ratio of activated Tfh/Tfr cells compared to inactive patients. In vitro study showed that IL-2, but not other cytokines such as TGF-β1, IL-12, IL-27, and IL-35, induced the conversion of memory Tfh cells to functional Tfr cells characterized by CXCR5+Bcl6+Foxp3hipSTAT3+pSTAT5+cells. The loci ofFOXP3at STAT binding sites were marked by bivalent histone modifications. After IL-2 stimulation, STAT5 directly bound on FOXP3 gene loci accompanied by suppressing H3K27me3. Finally, we found that serum level of IL-2 was decreased in SLE and that stimulation with IL-2 suppressed the generation of CD38+CD27+B cells by ex vivo coculture assay using Tfh cells and B cells isolated from human blood.

Conclusion:

Our findings indicated that the regulatory function of Tfr cells is impaired due to the low ability of IL-2 production and that IL-2 restores the function of Tfr cells through conversion of Tfh cells to Tfr cells in SLE. Thus, the reinstatement of the balance between Tfh and Tfr cells will provide important therapeutic approaches for SLE.

References:

[1]Deng J, Wei Y, Fonseca VR, et al. T follicular helper cells and T follicular regulatory cells in rheumatic diseases. Nat Rev Rheumatol. 2019; 15 (8): 475-90.

Disclosure of Interests: :

He Hao: None declared, Shingo Nakayamada Grant/research support from: Mitsubishi-Tanabe, Takeda, Novartis and MSD, Speakers bureau: Bristol-Myers, Sanofi, Abbvie, Eisai, Eli Lilly, Chugai, Asahi-kasei and Pfizer, Yamagata Kaoru: None declared, Naoaki Ohkubo: None declared, Shigeru Iwata: None declared, Yoshiya Tanaka Grant/research support from: Asahi-kasei, Astellas, Mitsubishi-Tanabe, Chugai, Takeda, Sanofi, Bristol-Myers, UCB, Daiichi-Sankyo, Eisai, Pfizer, and Ono, Consultant of: Abbvie, Astellas, Bristol-Myers Squibb, Eli Lilly, Pfizer, Speakers bureau: Daiichi-Sankyo, Astellas, Chugai, Eli Lilly, Pfizer, AbbVie, YL Biologics, Bristol-Myers, Takeda, Mitsubishi-Tanabe, Novartis, Eisai, Janssen, Sanofi, UCB, and Teijin

FRI0102 SERUM TNFΑ LEVELS AT 24 HOURS AFTER FIRST ADMINISTRATION OF CERTOLIZUMAB PEGOL PREDICT EFFECTIVENESS AT WEEK 12 IN PATIENTS WITH RHEUMATOID ARTHRITIS FROM TSUBAME STUDY (UMIN ID:0002381)

Background:

To increase the remission rate of rheumatoid arthritis (RA), it is necessary to determine the efficacy of the tumor necrosis factor (TNF) inhibitor as early as possible. Moreover, the response to certolizumab pegol (CZP) at 12 weeks has been reported to predict its long-term efficacy.

Objectives:

As part of a prospective single-center observational study (TSUBAME study), we prospectively enrolled patients to be treated with CZP in our institution to evaluate its effectiveness and safety starting at 24 hours after the first dose in clinical settings, while recording blood CZP concentrations and biomarkers over time to examine their correlation with clinical effects.

Methods:

One hundred patients with RA and inadequate response to MTX who received CZP were enrolled in the TSUBAME study. The changes in serum TNFα, IL-6, and CZP levels at 24 hours after first administration of CZP were measured, and the correlation between serum biomarkers and clinical response was determined.

Results:

At 24 hours after CZP initiation, significant improvement was observed in the disease activity (baseline and 24 h: 5.4 ± 1.3, 5.0 ± 1.3, respectively, p < 0.01), which was maintained until week 12. (baseline and 12 w: 5.4 ± 1.3, 3.3 ± 1.4, respectively, p < 0.01). Serum TNFα and IL-6 levels significantly decreased at 24 hours after first administration of CZP compared to baseline. No correlation was found between TNFα and IL-6 levels at baseline and the clinical response. According to univariate analysis, low serum TNFα and IL-6 levels and high CZP levels at 24 hours were associated with DAS28 (ESR) remission at 12 weeks. According to multivariate analysis, low serum TNFα levels at 24 hours were significantly associated with DAS28 (ESR) remission at 12 weeks (OR 0.05, 95%CI 0.01, 0.75, p = 0.03). Based on these findings, an ROC curve was created using remission according to the DAS28 (ESR) at week 12 as a dependent variable and TNFα concentration at 24 hours as an independent variable, resulting in a cut-off value of 0.76 pg/ml. From this result, the TNFα concentration at 24 hours was divided into 2 groups according to this cut-off, and the rates of remission according to the DAS28 (ESR) at week 12 were compared. In the group with TNFα concentration at 24 hours below the cut-off value, the rate of remission according to the DAS28 (ESR) at week 12 was significantly higher than in the group with TNFα concentration at 24 hours above the cut-off value (below the cut-off: above the cut-off = 56.3%: 21.6%, p < 0.001). Between the group that achieved remission according to the DAS28(ESR) and the group that did not achieve remission at week 12, there was almost no difference in the distribution of TNFα concentrations at baseline; however, the distribution of TNFα concentrations at 24 hours was lower in the group that achieved remission.

Conclusion:

CZP was effective where serum TNFα was strongly neutralized within 24 hours. These results suggest that low serum TNFα levels at 24 hours after first administration of CZP may predict the effectiveness of CZP. To increase the remission rate in RA, it is necessary to determine the effectiveness of the molecular targeted drugs used at an early point, in addition to how rapid the onset of action is. CZP is extremely fast-acting, and its effectiveness can be predicted as early as 24 hours after the first dose, suggesting that it may be possible to determine the effectiveness early.

Acknowledgments:

The authors thank Ms. M. Hirahara for providing excellent technical assistance.

Disclosure of Interests:

Yusuke Miyazaki Grant/research support from: Astellas Pharma Inc and UCB S.A., Kazuhisa Nakano: None declared, Shingo Nakayamada Grant/research support from: Mitsubishi-Tanabe, Takeda, Novartis and MSD, Speakers bureau: Bristol-Myers, Sanofi, Abbvie, Eisai, Eli Lilly, Chugai, Asahi-kasei and Pfizer, Satoshi Kubo: None declared, Shigeru Iwata: None declared, Kentaro Hanami: None declared, Shunsuke Fukuyo: None declared, Ippei Miyagawa: None declared, Ayako Yamaguchi: None declared, Akio Kawabe: None declared, SAITO KAZUYOSHI: None declared, Yoshiya Tanaka Grant/research support from: Asahi-kasei, Astellas, Mitsubishi-Tanabe, Chugai, Takeda, Sanofi, Bristol-Myers, UCB, Daiichi-Sankyo, Eisai, Pfizer, and Ono, Consultant of: Abbvie, Astellas, Bristol-Myers Squibb, Eli Lilly, Pfizer, Speakers bureau: Daiichi-Sankyo, Astellas, Chugai, Eli Lilly, Pfizer, AbbVie, YL Biologics, Bristol-Myers, Takeda, Mitsubishi-Tanabe, Novartis, Eisai, Janssen, Sanofi, UCB, and Teijin

P107 Predictors of increased d-dimer level at follow-up period after transcatheter aortic valve implantation.Is oral anticoagulation therapy better?

Background

Recently, there are some reports that hypo-attenuated leaflet thickening (HALT) following transcatheter aortic valve implantation (TAVI) is incidentally detected by multi-slice computed tomography. It is believed that valve thrombosis causes HALT, because oral anticoagulation therapy (OAC) is effective for HALT regression. Furthermore, it is reported that d-dimer level increases in patients with HALT, and might be a key biomarker to detect HALT.

Purpose

We sought to investigate the predictors related to increased d-dimer level at 6 months after follow-up TAVI.

Methods

We enrolled 124 consecutive patients who underwent successful TAVI between 2016 and 2018. Study patients were classified into two groups according to antithrombotic therapy resume (OAC therapy or anti-platelet therapy).We set the primary endpoint as the d-dimer levels at 6 months after TAVI. To evaluate the risks of the primary endpoint, we employed a multivariable linear regression model, setting the primary endpoint as an objective variable and patient and clinical backgrounds as explanatory variables. Furthermore, we set the secondary endpoint as one-year bleeding event.

Results

The median age of patients was 83 years old (quartile 80-87). Patients who had taken OAC at 6 months follow-up after TAVI were 29.8%. The median d-dimer level at 6 months after TAVI was 1.3 (1.0-2.2) µg/ml, and OAC group had statistically lower d-dimer level at 6 months follow-up than those in non-OAC group (p = 0.020). Uni-variable liner regression model demonstrated that increased d-dimer level at follow-up had significant relationship with large effective orifice area (EOA) (p = 0.002) and low left ventricular ejection fraction (LVEF) (p = 0.048) after TAVI. Furthermore, large EOA (p = 0.003) and OAC therapy (p = 0.027) were independently associated with increased d-dimer level in multivariate analysis. Kaplan-Meier estimates revealed that there were no significant difference regarding one-year bleeding event between OAC group and non-OAC group (long-rank p = 0.167).

Conclusions

This study suggests that large EOA after TAVI is associated with increased d-dimer levels at 6 months after TAVI, and OAC therapy might have a potential to decrease d-dimer level after TAVI without increase of bleeding events.

Abstract P107 Figure: One-year bleeding event

P3693Self-expandable transcatheter aortic valve implantation is associated with frequent periprocedural stroke detected by diffusion-weighted magnetic resonance imaging -Insight from propensity score match

Background

Little evidence is available regarding the risk of peri-procedural stroke detected by diffusion-weighted magnetic resonance imaging (DW-MRI) after transcatheter aortic valve implantation (TAVI). Our purpose was to evaluate stroke risk after TAVI using DW-MRI by enrolling consecutive patients who underwent transfemoral TAVI and post-procedural DW-MRI.

Methods

We prospectively enrolled 113 consecutive patients who underwent transfemoral TAVI and post-procedural DW-MRI. We used balloon-expandable valves as first-line therapy and selected self-expandable valves only for patients with narrow sinotubular junctions or annuli. We set the primary endpoint as the number of high intensity areas (HIA) detected by DW-MRI regardless of the size of the area. To evaluate the risks of the primary endpoint, we employed a multivariable linear regression model, setting the primary endpoint as an objective variable and patient and clinical backgrounds as explanatory variables. In addition, the relationship between valve type and the number of HIAs on DW-MRI was also confirmed by the propensity score matching analysis to evaluate the robustness of the result, using a multivariable linear regression model with the protocol described in the previous manuscript. Shortly, the propensity score was calculated with a logistic regression model by setting the treatment as the response variable and baseline characteristics and procedural information that were significantly different between 2 groups (balloon expandable and self-expandable) as explanatory variables, which included age, estimated glomerular filtration rate, oversizing rate, and BAV before THV deployment.

Results

Median patient age was 84 years, and 36.3% were men. Ninety-three patients underwent balloon-expandable TAVI and 20 underwent self-expandable TAVI. Symptomatic stroke occurred in 6 (5.3%) whereas asymptomatic stroke occurred in 59 (52.2%) patients. The incidence of symptomatic and total stroke was higher in patients who underwent self-expandable TAVI than those who underwent balloon-expandable TAVI (30.0% vs 0.0%, p<0.001 and 90.0% vs 50.5%, p=0.001, respectively). A multivariable linear regression model demonstrated an increased primary endpoint when self-expandable TAVI was performed (p<0.001). The other covariates had no significant relationship to the primary endpoint. Akaike information criterion-based stepwise statistical model selection revealed that valve type was the only explanatory variable for the best predictive model. This result was also confirmed with the propensity score matching analysis (estimate, 2.359; 95% CI, 0.426–4.292; p=0.019) after adjustments of propensity score, in which 28 patients were matched (n=14 in each group).

Conclusions

Self-expandable valves were associated with increased numbers of HIA on DW-MRI after TAVI in patients with severe aortic stenosis.

Continuous cell culture monitoring using a compact microplate reader with a silicone optical technology-based spatial filter

Continuous cell monitoring is very important for the maintenance and control of cell multiplication and differentiation. This paper presents a compact microplate reader that is able to continuously measure a 24-well microplate (6 × 4 wells) using the optical absorption measurement method. The 24-channel plate reader consisted of a spatial filter, light emitting diode light source, and color sensors and was similarly sized with the cell culture microwell plates. A spatial filter was previously fabricated by our group using silicone optical technology (SOT). This SOT-based spatial filter has an excellent noise reduction effect. Light reflection at the optical path interface can be absorbed and only forward light can be transmitted; accordingly, a larger S/N ratio than that of conventional optical systems is expected. The fabricated 24-channel plate reader permits real-time cell monitoring during cultivation on the clean bench and in cell culture conditions by incorporating the SOT spatial filter. Using the device, it was possible to continuously evaluate the concentration and pH of reagents in the 24 wells in real time. Moreover, cell activity and protein production were detectable using the device. These results suggest that the newly fabricated device is a promising tool for the evaluation of cell behaviors for cell management.

Efficacy and safety of anti-CD20 antibody rituximab for patients with refractory systemic lupus erythematosus

Objective

We examined the efficacy and safety of rituximab in patients with refractory systemic lupus erythematosus (SLE).

Methods

The study enrolled 63 SLE patients who were treated with rituximab between 2002 and 2015. The participants underwent a battery of tests before treatment and at one year. Treatment ranged from two to four times at 500 or 1000 mg.

Results

Baseline characteristics were males:females = 6:57, age 33.9 years, and disease duration 87.2 months. The primary endpoint: The rate of major clinical response (MCR) was 60% while the partial clinical response (PCR) was 25%. Thirty of 36 (83%) patients with lupus nephritis (WHO II: 2, III: 5, IV: 22, V: 4, IV+V: 2, not assessed: 1) and 22 of 24 patients (92%) with neuropsychiatric SLE, who could be followed at one year, showed changes from BILAG A or B score to C or D score at one year. Multivariate analysis identified high anti-dsDNA antibody and shorter disease duration as significant determinants of MCR at one year. Repeat examination was conducted at five years. Primary failure was recorded in 8.8% and secondary failure in 32.4% (time to relapse: 24.4 months). Rituximab was well tolerated although 65 adverse events, mostly infections, were recorded within one year.

Conclusion

Rituximab is potentially efficacious for the treatment of patients with refractory SLE.

A case of refractory lupus nephritis complicated by psoriasis vulgaris that was controlled with secukinumab

It has been reported that T helper 17 cells are involved in the pathogenesis of systemic lupus erythematosus, but there is no report on interleukin-17-targeted therapy. We report a case of a 62-year-old female who presented with psoriasis vulgaris and refractory lupus nephritis. Because her conditions were resistant to conventional treatment, and flow cytometry confirmed the proliferation of activated T helper 17 cells in peripheral blood, and examination of a renal biopsy tissue sample confirmed infiltration of numerous interleukin-17-positive lymphocytes to the renal interstitium, administration of the anti-interleukin-17A antibody secukinumab was initiated. After starting secukinumab the clinical and biological features were improved.

B-cell subsets, signaling and their roles in secretion of autoantibodies

B cells play a pivotal role in the pathogenesis of autoimmune diseases. In patients with systemic lupus erythematosus (SLE), the percentages of plasmablasts and IgD−CD27− double-negative memory B cells in peripheral blood are significantly increased, while IgD+CD27+ IgM memory B cells are significantly decreased compared to healthy donors. The phenotypic change is significantly associated with disease activity and concentration of autoantibodies. Treatment of B-cell depletion using rituximab results in the reconstitution of peripheral B cells in SLE patients with subsequent improvement in disease activity. Numerous studies have described abnormalities in B-cell receptor (BCR)-mediated signaling in B cells of SLE patients. Since differences in BCR signaling are considered to dictate the survival or death of naïve and memory B cells, aberrant BCR signal can lead to abnormality of B-cell subsets in SLE patients. Although Syk and Btk function as key molecules in BCR signaling, their pathological role in SLE remains unclear. We found that Syk and Btk do not only transduce activation signal through BCR, but also mediate crosstalk between BCR and Toll-like receptor (TLR) as well as BCR and JAK-STAT pathways in human B cells in vitro. In addition, pronounced Syk and Btk phosphorylation was observed in B cells of patients with active SLE compared to those of healthy individuals. The results suggest the involvement of Syk and Btk activation in abnormalities of BCR-mediated signaling and B-cell phenotypes during the pathological process of SLE and that Syk, Btk and JAK are potential therapeutic targets in SLE.

Ultrafast spin-switching of a ferrimagnetic alloy at room temperature traced by resonant magneto-optical Kerr effect using a seeded free electron laser

Ultrafast magnetization reversal of a ferrimagnetic metallic alloy GdFeCo was investigated by time-resolved resonant magneto-optical Kerr effect measurements using a seeded free electron laser. The GdFeCo alloy was pumped by a linearly polarized optical laser pulse, and the following temporal evolution of the magnetization of Fe in GdFeCo was element-selectively traced by a probe free electron laser pulse with a photon energy tuned to the Fe M-edge. The results have been measured using rotating analyzer ellipsometry method and confirmed magnetization switching caused by ultrafast heating.

Increased Syk phosphorylation leads to overexpression of TRAF6 in peripheral B cells of patients with systemic lupus erythematosus

OBJECTIVE

Activation of B cells is a hallmark of systemic lupus erythematosus (SLE). Syk and TRAF6 are key signaling molecules in B-cell activation through BCR and CD40/TLR, respectively. Nevertheless, whether expression of Syk and TRAF6 is altered in SLE B cells remains unknown.

METHODS

Phosphorylation and/or expression of Syk and TRAF6 were analyzed by flow cytometry in peripheral blood mononuclear cells isolated from SLE patients.

RESULTS

Pronounced phosphorylation and expression of Syk were noted in B cells from SLE patients compared with healthy donors. Levels of Syk phosphorylation correlated with the disease activity score. TRAF6 was significantly over-expressed in B cells of SLE patients as compared with healthy donors, and significant correlation of levels of TRAF6 expression and Syk phosphorylation was observed in SLE patients. Levels of TRAF6 expression were more pronounced in CD27+ memory B cells than in CD27-naïve B cells. In vitro treatment of SLE B cells with a Syk inhibitor (BAY61-3606) reduced Syk phosphorylation as well as TRAF6 expression.

CONCLUSION

Our results suggest that the activated Syk-mediated TRAF6 pathway leads to aberrant activation of B cells in SLE, and also highlight Syk as a potential target for B-cell-mediated processes in SLE.

Diaphyseal osteosarcomas have distinct clinical features from metaphyseal osteosarcomas

AIMS

The aim of this study was to clarify the clinical features and outcomes of diaphyseal osteosarcoma.

METHODS

Patients with newly-diagnosed high-grade osteosarcoma occurring in the long bone were eligible for this retrospective study. Clinicopathological information was collected from our database and compared with 36 diaphyseal, 405 proximal and 519 distal metaphyseal, and 14 whole bone osteosarcoma patients. Additionally, case-control study matching by age, gender, site, and metastatic status at diagnosis with 1:3 ratio of 36 diaphyseal to 108 metaphyseal osteosarcomas patients was also conducted.

RESULTS

Five-year overall survival and metastasis-free survival of the three groups including diaphyseal, metaphyseal, and whole bone osteosarcoma patients showed significant difference (P = .029 and P = .013, respectively), although there is no difference for the survivals between proximal and distal metaphyseal osteosarcoma patients. Case-control study showed that patients with diaphyseal osteosarcomas had a significantly larger tumour (mean 13.5 cm vs 10 cm, P = .026), and demonstrated higher pathologic fracture rate (28% vs 12%, P = .033), superior 5-year metastasis-free survival (74% vs 40%, P = .0068), and slightly better 5-year overall survival (68% vs 46%, P = .074). Prognostic factor analysis showed that a pathologic fracture significantly decreased the survival of the patients with diaphyseal osteosarcoma.

CONCLUSIONS

The current study showed that diaphyseal osteosarcoma has distinct clinical features from metaphyseal osteosarcoma having an increased risk of pathologic fractures but with favorable survival outcome.

Regulation of somatostatin receptor 4-mediated cytostatic effects by CD26 in malignant pleural mesothelioma

Background:

Malignant pleural mesothelioma (MPM) is an aggressive neoplasm arising from mesothelial lining of pleura. CD26 molecules preferentially expressed on epithelioid type of MPM. This study investigates the molecular mechanisms of CD26 regulating MPM cells in vitro and in vivo.

Methods:

Biochemical and cell biological approaches were used for identifying a novel molecular target of MPM. Its contribution to tumour expansion has been also assessed using animal models. The clinical samples of MPM were also assessed for its expression.

Results:

We identify that cytostatic effects in MPM are mediated by somatostatin (SST) receptor 4 (SSTR4), being inhibited by the interaction of CD26 molecules. We also indicates that SSTR4-mediated cytostatic effects are regulated by SHP-2 PTP, and that this inhibitory effect by SST agonist is enhanced via lipid raft clustering of associated molecules following crosslinking of anti-CD26 antibody. Finally, using an in vivo xenograft model, we demonstrate that the anti-tumour effect of anti-CD26 mAb is enhanced when combined with SSTR4 agonist treatment, and that SSTR4 is highly coexpressed with CD26 on epithelioid or biphasic types of MPM tissues obtained from patients' surgical specimens.

Conclusions:

Combination therapy with humanised anti-CD26 mAb and SSTR4 agonist may therefore potentiate anti-tumour effect on MPM.

Selective loss of parvalbumin-positive GABAergic interneurons in the cerebral cortex of maternally stressed Gad1-heterozygous mouse offspring

Exposure to maternal stress (MS) and mutations in GAD1, which encodes the γ-aminobutyric acid (GABA) synthesizing enzyme glutamate decarboxylase (GAD) 67, are both risk factors for psychiatric disorders. However, the relationship between these risk factors remains unclear. Interestingly, the critical period of MS for psychiatric disorders in offspring corresponds to the period of GABAergic neuron neurogenesis and migration in the fetal brain, that is, in the late stage of gestation. Indeed, decrement of parvalbumin (PV)-positive GABAergic interneurons in the medial prefrontal cortex (mPFC) and hippocampus (HIP) has often been observed in schizophrenia patients. In the present study, we used GAD67-green fluorescent protein (GFP) knock-in mice (that is, mice in which the Gad1 gene is heterozygously deleted; GAD67(+/GFP)) that underwent prenatal stress from embryonic day 15.0 to 17.5 and monitored PV-positive GABAergic neurons to address the interaction between Gad1 disruption and stress. Administration of 5-bromo-2-deoxyuridine revealed that neurogenesis of GFP-positive GABAergic neurons, but not cortical plate cells, was significantly diminished in fetal brains during MS. Differential expression of glucocorticoid receptors by different progenitor cell types may underlie this differential outcome. Postnatally, the density of PV-positive, but not PV-negative, GABAergic neurons was significantly decreased in the mPFC, HIP and somatosensory cortex but not in the motor cortex of GAD67(+/GFP) mice. By contrast, these findings were not observed in wild-type (GAD67(+/+)) offspring. These results suggest that prenatal stress, in addition to heterozygous deletion of Gad1, could specifically disturb the proliferation of neurons destined to be PV-positive GABAergic interneurons.

Role of the β1 integrin molecule in T-cell activation and migration

Abstract β1 integrins play crucial roles in a variety of cell processes such as adhesion, migration, proliferation, and differentiation of lymphocytes. To understand the molecular mechanisms of these various biological effects, it is particularly important to analyze cell signaling through the β1 integrins. Our previous study showed that PLC-γ, pp125FAK (focal adhesion kinase), pp105, paxillin, p59fyn, p56lck, and ERK1/2 are phosphorylated in their tyrosine residues upon engagement of β1 integrins. We identified pp105 as Cas (Crk-associated substrate)-related protein and successfully cloned its cDNA. pp105 is a Cas homologue predominantly expressed in the cells of lymphoid lineage, which led us to designate it Cas-L. Like p130Cas, Cas-L contains a single SH3 domain and multiple SH2-binding sites (YXXP motif), which are suggested to bind SH2 domains of Crk, Nck, and SHPTP2. Subsequent studies revealed that pp125FAK binds Cas-L on its SH3 domain and phosphorylates its tyrosine residues upon β1 integrin stimulation. Since Cas-L is preferentially expressed in lymphocytes, it is conceivable that Cas-L plays an important role in lymphocyte-specific signals. We have shown that Cas-L is involved in the T-cell receptor (TCR)/CD3 signaling pathway as well as the β1 integrin signaling pathway. Cas-L is transiently phosphorylated following CD3 crosslinking and tyrosine-phosphorylated Cas-L binds to Crk and C3G. Furthermore, a Cas-L mutant (Cas-LΔSH3), which lacks the binding site for FAK, is still tyrosine-phosphorylated upon CD3 crosslinking but not upon β1 integrin crosslinking, suggesting that FAK is not involved in CD3-dependent Cas-L phosphorylation. Finally, we have identified a crucial role of Cas-L in β1 integrin-mediated T-cell co-stimulation. We have found that this co-stimulatory pathway is impaired in the Jurkat T-cell line, and that the expression level of Cas-L is reduced in the Jurkat cells compared to peripheral T-cells. The transfection of Cas-L cDNA into Jurkat cells restored the β1 integrin-mediated co-stimulation, while the transfection of Cas-LΔSH3 mutant failed to do so, which contrasts with the case of CD3-mediated signaling. These results indicate that Cas-L plays a key role, through the association and phosphorylation by FAK, in β1 integrin-mediated T-cell co-stimulation. Moreover, tyrosine phosphorylation of Cas-L is critical for T-cell receptor and β1 integrin-induced T-lymphocyte migration. Taken together, Cas-L might be the bi-modal docking protein which assembles the signals through β1 integrins and TCR/CD3, and which participates in a variety of T-cell functions.

Effect of parathyroidectomy on subclinical cardiovascular disease in mild primary hyperparathyroidism

OBJECTIVE

We recently demonstrated that mild primary hyperparathyroidism (PHPT) is associated with increased carotid intima-media thickness (IMT) and stiffness, and increased aortic valve calcification. It is unclear whether parathyroidectomy (PTX) improves these abnormalities. The purpose of this study was to determine whether cardiovascular abnormalities in PHPT improve with PTX.

DESIGN

Forty-four patients with PHPT were studied using carotid ultrasound and transthoracic echocardiography before and after PTX. Carotid IMT, carotid plaque and stiffness, left ventricular mass index (LVMI), myocardial and valvular calcification, and diastolic function were measured before, 1- and 2-year post-PTX.

RESULTS

Two years after PTX, increased carotid stiffness tended to decline to the normal range (17%, P=0.056) while elevated carotid IMT did not improve. Carotid plaque number and thickness, LVMI and cardiac calcifications did not change after PTX, while some measures of diastolic function (isovolumic relaxation time (IVRT) and tissue Doppler peak early diastolic velocity) worsened within the normal range. Indices did improve in patients with cardiovascular abnormalities at baseline. Increased carotid stiffness improved by 28% (P=0.004), a decline likely to be of clinical significance. More limited improvements also occurred in elevated IMT (3%, P=0.017) and abnormal IVRT (13%, P<0.05), a measure of diastolic dysfunction.

CONCLUSIONS

In mild PHPT, PTX led to modest changes in some cardiovascular indices. Improvements were mainly evident in those with preexisting cardiovascular abnormalities, particularly elevated carotid stiffness. These findings are reassuring with regard to current international guidelines that do not include cardiovascular disease as a criterion for PTX.

Experimental evidence of reaction-driven miscible viscous fingering

An experimental demonstration of reaction-driven viscous fingering developing when a more viscous solution of a reactant A displaces a less viscous miscible solution of another reactant B is presented. In the absence of reaction, such a displacement of one fluid by another less mobile one is classically stable. However, a simple A+B→C reaction can destabilize this interface if the product C is either more or less viscous than both reactant solutions. Using the pH dependence of the viscosity of some polymer solutions, we provide experimental evidence of both scenarios. We demonstrate quantitatively that reactive viscous fingering results from the buildup in time of nonmonotonic viscosity profiles with patterns behind or ahead of the reaction zone, depending on whether the product is more or less viscous than the reactants. The experimental findings are backed up by numerical simulations.