POS0760 HIGH LEVELS OF PROTEINS, CELL COUNTS, AND IL-6 IN CEREBROSPINAL FLUID IN PATIENTS WITH NEUROPSYCHIATRIC SYSTEMIC LUPUS ERYTHEMATOSUS ARE ASSOCIATED WITH DAMAGE ACCRUAL OF NON-NEUROPSYCHIATRIC DOMAINS AS WELL AS THAT OF NEUROPSYCHIATRIC DOMAINS

Background

Neuropsychiatric systemic lupus erythematosus (NPSLE) is one of severe organ manifestations and directly associated with neuropsychiatric damages, such as cerebral vascular accident, cognitive impairment, or seizures. However, factors associated with damage accrual of neuropsychiatric and non-neuropsychiatric domains in NPSLE patients remain unknown.

Objectives

The aim of this study was to identify factors associated with damage accrual in patients with NPSLE.

Methods

We reviewed all patients with SLE who had attended our hospital between January 2010 to December 2020 retrospectively and identified those with NPSLE. We analyzed clinical characteristics and laboratory data including cerebrospinal fluid (CSF) in association with the Systemic Lupus International Collaborating Clinics/American College of Rheumatology (SLICC/ACR) damage index (SDI) progression after the onset of NPSLE.

Results

461 patients with SLE were reviewed. Among them, 37 (8.0%) were diagnosed with NPSLE. Thirty-six patients were included in the analysis after excluding one patient with insufficient information. Seventeen (47.2%) patients were diagnosed with NPSLE at the same time with SLE diagnosis and 19 patients were diagnosed at relapse. At NPSLE onset, the mean age was 33.7 years, 35 were female, and the mean SLEDAI-2K was 21.8. Eighteen (50.0%) patients had active lupus nephritis simultaneously at the onset of NPSLE. The most frequent NPSLE types according to the 1999 ACR classification were lupus headache in 10 patients, followed by cerebrovascular disease in 7, seizure disorders in 6, acute confusional state, psychosis and mononeuropathy in 3, and aseptic meningitis in 2. All patients were treated with glucocorticoids, and the mean initial dose of prednisolone was 52.3 mg/day with steroid pulse therapy in 19 patients. Thirty (83.3%) patients were treated with concomitant immunosuppressive treatments. During the observation period with the mean of 10.0 years, 17 (47.2%) patients developed at least one point of SDI. Among them, 9 patients (25.0%) had neuropsychiatric damage progression including cerebrovascular accident in 6, seizures requiring drug treatment for more than 6 months in 2, and cognitive impairment in 1. Non-neuropsychiatric damage was also increased such musculoskeletal in 5, ocular in 3, cardiovascular in 2, renal, gastrointestinal, premature gonadal failure, diabetes, and malignancy in each one case. Neither neuropsychiatric nor overall damage progression were associated with SLEDAI-2K, anti-cardiolipin antibodies positivity, abnormal electroencephalogram, abnormal single photon-emission computed tomography at NPSLE onset or kinds of immunosuppressive treatments. In 21 patients who underwent CSF examination, the high level of CSF IL-6 was associated with neuropsychiatric damage progression (p=0.032). Also, high levels of CSF protein (p=0.030), cell counts (p=0.007), and IL-6 (p=0.032) were associated with overall SDI progression.

Conclusion

CSF IL-6 concentrations are associated with neuropsychiatric damage progression, and high CSF protein, cell counts and IL-6 at onset in patients with NPSLE can predict overall damage accrual.

References

[1]Liang MH, Corzillius M, Bae SC, et al. The American College of Rheumatology nomenclature and case definitions for neuropsychiatric lupus syndromes. Arthritis Rheum 1999; 42: 599–608.

[2]Gladman D, Ginzler E, Goldsmith C, et al. The development and initial validation of the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index for systemic lupus erythematosus. Arthritis Rheum 1996; 39: 363–369.

Disclosure of Interests

None declared

POS1436 CLINICAL CHARACTERISTICS AND RISK FACTORS OF INVASIVE FUNGAL INFECTION DURING IMMUNOSUPPRESSIVE INDUCTION THERAPY IN PATIENTS WITH CONNECTIVE TISSUE DISEASE

Background

Invasive fungal infection (IFI) is a life-threatening complication among immunosuppressed patients. Whereas intensive immunosuppressive therapy during remission induction phase in patients with connective tissue disease is a major risk of IFI, little is known about the clinical characteristics and risk factors of IFI.

Objectives

This study aims to reveal prevalence, clinical characteristics, and associated risk factors of IFI during immunosuppressive induction therapy in patients with connective tissue disease.

Methods

We reviewed consecutive patients with connective tissue diseases who underwent immunosuppressive remission induction therapy in Keio University Hospital Rheumatology Department from January 2012 to August 2020. Patients with 0.5mg/kg or more equivalent dose of daily prednisone use were included for IFI, diagnosed according to the definition of invasive fungal diseases from EORTC/MSG 2008. Infections caused by Pneumocystis jirovecii were not included.

Results

Among 2701 hospitalized cases, 627 patients had undergone induction or re-induction therapy. Total of 24(3.8%) patients were diagnosed as IFI, of whom there were 8 proven cases and 16 probable cases; 14 aspergillosis, 5 candidiasis, 2 cryptococcosis, 1 phaeohyphomycosis, and 2 cases with unknown pathogen. Median duration from the start of immunosuppressive therapy to the onset of IFI was 95 days (interquartile range, 36,249 days; range, 13-1397 days) and the mean dose of daily prednisolone was 0.53±0.29 mg/kg at the onset of IFI. Total of 11 patients died; 6 patients (25.0%) due to IFI and 5 patients (20.8%) due to the exacerbation of underlying disease. Univariable analysis comparing the IFI and non-IFI groups, age (65.8±3.7 vs. 56.1±0.7; P=0.01), initial prednisolone dose (0.87±0.01 vs 0.95±0.04 mg/kg; P=0.037), the history of methylprednisolone (mPSL) pulse therapy (54.2% vs. 20.0%; P<0.001), tumor necrosis factor (TNF) inhibitor use (8.3% vs. 1.1%; P=0.039), 2 or more immunosuppressant or biologic use (33.3% vs. 12.9%; P=0.010), HbA1c 6.5% or higher (58.3% vs. 28.9%; P=0.003), lowest serum IgG during the clinical course (599.4±62.1 vs 787.7±12.4 mg/dl; P=0.003), and cytomegalovirus reactivation defined by pp65 antigen 6 or higher (33.3% vs. 11.2%; P=0.004) were significantly different, respectively. Sex, body mass index, presence of interstitial lung disease, and the use of cyclophosphamide, rituximab, or interleukin-6 inhibitors were not significantly different. Multivariable analysis revealed older age (for each 10-year increase: OR 1.40, 95% CI 1.03-1.91; P=0.023), the history of methylprednisolone pulse therapy (OR 2.60, 95% CI 1.06-6.77; P=0.049), TNF inhibitor use (OR 11.2, 95% CI 1.70-74.0; P=0.012), and serum IgG less than 550 mg/dl (OR 2.59, 95% CI 1.03-6.55; P=0.041) as the independent risk factors of IFI.

Conclusion

Patients with connective tissue disease with older age, lower serum IgG, mPSL pulse therapy, or TNF inhibitor use are at higher risk of IFI. Further studies are needed to determine the benefit of prophylactic anti-fungal treatment in such patients.

References

[1]De Pauw B, Walsh TJ, Donnelly JP, et al. Revised definitions of invasive fungal disease from the European Organization for Research and Treatment of Cancer/Invasive Fungal Infections Cooperative Group and the National Institute of Allergy and Infectious Diseases Mycoses Study Group (EORTC/MSG) Consensus Group. Clin Infect Dis. 2008;46(12):1813-1821.

Disclosure of Interests:

None declared

POS0459 APTAMER-BASED PROTEOMIC SCREENING IN IDENTIFICATION OF PATHOGENIC SIGNAL PATHWAY AND URINARY BIOMARKERS ASSOCIATED WITH HISTOLOGICAL FINDINGS IN LUPUS NEPHRITIS

Background

The current gold standard for the diagnosis and classification, assessment of the severity of lupus nephritis (LN) is a renal biopsy. On the other hand, since the procedure is highly invasive, there is a pressing need to identify biomarkers for predicting the presence and its histological severity of LN. In addition, the background pathogenesis of each histological findings is not clearly understood.

Objectives

The purpose of this study was to elucidate the urine biomarkers for predicting the presence and the severity of histological findings of LN, and to search the pathogenic signal pathway.

Methods

Urine samples from 24 biopsy-proven active LN patients were initially screened for the levels of 1305 distinct human proteins using an aptamer-based-targeted proteomic assay. We developed histological scoring system based on ISN/RPS lesion definitions and classification, NIH activity and chronicity score. Two experienced evaluators assessed the histological scores. Cluster analysis and pathway analysis were performed.

Results

A total of 24 LN patients were included: 20 (83%) had a proliferative histological class (III or IV +/-V), 4 (17%) pure membranous (V). Through cluster analysis, several histological subgroups were extracted according to correlation with each histological finding, and proteins which corelated with each histological scores were analyzed. We focused on two subgroups: one in which including active glomerular histological findings (endocapillary hypercellularity, karyorrhexis, neutrophil infiltration, subendothelial deposits) and the other in which including interstitial histological findings (interstitial inflammation, interstitial fibrosis, tubular atrophy). Histological scores in the former group showed strong positive correlation with protein group which contained 59 proteins (Group A), including CCL21, CXCL10, VCAM1. Histological scores in the latter group corelated with another protein group which contained 85 proteins (Group B), including MCP-1, CCL11. Ingenuity Pathway Analysis showed 16 pathways (PDGF Signaling, Granulocyte Adhesion and Diapedesis, etc) were upregulated in Group A and 11 pathways (IL-17 signaling, Fibrosis signaling pathway, etc) upregulated in Group B. Among group A and group B urine proteins, those showed strong correlation between respective histological findings were validated with ELISA assays.

Conclusion

An aptamer-based-targeted proteomic assay screening by combining with renal histological scoring system suggested several urine proteins can predict the severity and the presence of major renal histological findings, and suggested to be related with the pathogenesis in patients with LN.

Disclosure of Interests

Kazuoto Hiramoto: None declared, Shuntaro Saito: None declared, Hironari Hanaoka: None declared, Katsuya Suzuki: None declared, Jun Kikuchi: None declared, Hiroyuki Fukui: None declared, Ryo Takano Employee of: Mitsubishi Tanabe Pharma Corporation Sohyaku, Fumihiko Miyoshi Employee of: Mitsubishi Tanabe Pharma Corporation Sohyaku, Noriyasu Seki Employee of: Mitsubishi Tanabe Pharma Corporation Sohyaku, Kunio Sugahara Employee of: Mitsubishi Tanabe Pharma Corporation Sohyaku, Yuko Kaneko: None declared, Tsutomu Takeuchi: None declared.

POS1183 RISK FACTORS FOR CYTOMEGALOVIRUS INFECTION IN PATIENTS WITH RHEUMATIC DISEASE; SINGLE-CENTER PROSPECTIVE COHORT STUDY

Background

Cytomegalovirus (CMV) infection is one of serious opportunistic infections for immunosuppressed patients, therefore, identifying patients at risk for CMV infection is of importance. However, no prospective study about CMV infection in systemic rheumatic disease has been reported.

Objectives

To identify risk factors relevant with CMV infection in patients with systemic rheumatic disease during intensive remission induction therapy.

Methods

Consecutive systemic rheumatic disease cases who started intensive immunosuppressive therapy from February 2017 until February 2019 were enrolled. Serum CMV-IgG was measured before the induction therapy, and subsequently, CMV pp65 antigen was monitored weekly. Patients were divided into 2 groups according to the presence or absence of CMV infection, and risk factors for CMV infection were analyzed.

Results

157 patients consisting of 136 CMV-IgG positive and 21 CMV-IgG negative patients were enrolled in the study. Mean age was 60.8 ± 17.4 y/o, and female was 70.7%. The underlying diseases were following; vasculitides 54, systemic lupus erythematosus 27, polymyositis/dermatomyositis 25, rheumatoid arthritis 14, IgG4-related disease 13, mixed connected tissue disease 6, Behçet disease 5, adult-onset Still’s disease 4, and others 9. The initial dose of glucocorticoid (GC) was 48.4 ± 11.5 mg/day (0.91 ± 0.16 mg/kg/day) as prednisolone (PSL) with additional methylprednisolone (mPSL) pulse therapy being conducted in 44 (28.0%). Concomitant immunosuppressive therapies were intravenous cyclophosphamide (IVCY) in 55, calcineurin inhibitor 27, mycophenolate mofetil 16, hydroxychloroquine 5, and methotrexate 4. Concomitant biological agents were rituximab 12, tocilizumab 6, infliximab 2, golimumab 1, and abatacept 1. CMV infection occurred in 52 patients (33.1%), and all of them were CMV-IgG positive before induction therapy (38.2% in the CMV-IgG positive patients). Univariable analysis revealed initial PSL dose >0.91 mg/kg/day (odds ratio [OR] 5.2, p<0.01), IVCY (OR 3.4, p<0.01), diabetes mellitus (OR 5.2, p<0.01), and a history of malignancy (OR 2.9, p=0.02) were independent risk factors for CMV infection. CMV antiviral drugs were administered in 22 patients (42.3%). At the first detection of CMV pp65 antigen, PSL dose ≥37.5 mg/day (OR 5294.8, p<0.01), CMV pp65 antigen-positive cells ≥2 cells/2 slides (OR 16.0, p = 0.04), and serum albumin levels <3.0 g/dL (OR 26.3, p=0.01) were associated with subsequent CMV antiviral drug administration.

Conclusion

CMV infection occurred only in CMV-IgG positive patients with systemic rheumatic diseases who were undergoing intensive remission induction therapy. CMV infection was related with treatment regimen and comorbidities, and the necessity of CMV antiviral treatment was predicted with prednisolone dose, the number of CMV pp65 antigen positive cells, and albumin levels at the first detection of CMV pp65 antigen.

Disclosure of Interests

None declared

POS0257 COMPARISON OF SARS-CoV-2 VACCINE RESPONSE IN PATIENTS WITH INFLAMMATORY RHEUMATIC DISEASE; mRNA-1273 VACCINE INDUCES HIGHER HUMORAL IMMUNOGENICITY THAN BNT162b2

Background

The SARS-CoV-2 messenger RNA (mRNA) vaccines BNT162b2 (Pfizer-BioNTech) and mRNA-1273 (Moderna) have benefitted all countries amid the coronavirus disease 2019 (COVID-19) crisis. Whereas both of them have shown efficacy in preventing COVID-19 illness in healthy participants, there is paucity of data about immunogenicity and safety of mRNA COVID-19 vaccines in patients with autoimmune, inflammatory rheumatic disease. Recent observational studies evaluated mainly BNT162b2, suggesting that glucocorticoids, immunosuppressive agents impair SARS-CoV-2 vaccine responses. However, difference in immune reactions and safety between BNT162b2 and mRNA-1273 have not been clarified in patients with inflammatory rheumatic diseases.

Objectives

To assess humoral and T cell immune responses and safety profiles after two doses of different mRNA vaccine against SARS-CoV-2; BNT162b2 and mRNA-1273.

Methods

We enrolled consecutive, previously uninfected patients with inflammatory rheumatic diseases receiving mRNA vaccine including BNT162b2 and mRNA-1273. Healthy participants receiving BNT162b2 were also recruited as control. Blood samples were obtained 3weeks, 2 months, 3 months, 4 months, and 6 months after second dose of vaccines. We measured titres of neutralizing antibodies against SARS-CoV-2 and calculated seroconversion rates to evaluate humoral responses. We also assessed T-cell immunity responses by using interferon releasing assay against SARS-CoV-2 in a part of the patients. Answers to questionnaires about adverse reactions were obtained from participants.

Results

A total of 974 patients with inflammatory rheumatic diseases and healthy 630 control participants were enrolled. Among them, 796 patients received BNT162b2, 178 patients received mRNA-1273, and all control participants received BNT162b2. Seroconversion rates and neutralizing antibody titres 3 weeks after vaccination were significantly higher in patients with mRNA-1273 and healthy participants with BNT162b2 compared with patients with BNT162b2; seroconversion rates, 97.2% vs 99.5% vs 83.3%, p<0.001; titers of neutralizing antibodies, 29.4±33.9 IU/mL vs 23.9±14.2 IU/mL vs 10.8±16.5 IU/mL, p<0.001, respectively. On another front, T cell reaction against SARS-CoV-2 was similar in both patients with mRNA-1273 and BNT162b2; interferon gamma levels for antigen 1, 1.2±2.1 IU/mL vs 0.8±2.5 IU/mL, p=0.23; and for antigen 2, 1.4±1.9 IU/mL vs 1.0±2.1 IU/mL, p=0.11, respectively. Regarding adverse reaction of each mRNA vaccine, the frequency of systemic adverse reactions including fever and general fatigue are also significantly higher in patients with mRNA-1273 and healthy controls than patients with BNT162b2; fever, 48.0% vs 44.9% vs 10.2%, p<0.001; general fatigue, 70.4% vs 61.8% vs 31.2%, p<0.001, respectively). In longitudinal measurement, neutralizing antibody titres in patients with BNT162b2 were decreased more rapidly than those in healthy controls; 3.3±3.2 IU/mL in patients with BNT162b2 at 4 months and 3.2±4.7 IU/mL in healthy controls with BNT162b2 at 6 months. We identified age, glucocorticoid dose (prednisolone > 7.5mg), use of immunosuppressants including methotrexate, mycophenolate, cyclophosphamide, and tacrolimus are associated with rapid attenuation of humoral responses in patients with BNT162b2.

Conclusion

Our results demonstrated a significant higher humoral immunogenicity and frequency of systemic adverse reaction of the SARS-CoV-2 mRNA-1273 (Moderna) compared with the BNT162b2 (Pfizer-BioNTech) in inflammatory rheumatic disease patients. Glucocorticoid and immunosuppressive agents impaired induction and sustention of neutralizing antibody, and earlier third booster vaccination may be required within 4 months, especially for those receiving BNT162b2.

References

[1]Steensels D, Pierlet N, Penders J et al. JAMA. 2021;326(15):1533–1535.

[2]Friedman MA, Curtis JR and Winthrop KL. Ann Rheum Dis 2021;80:1255–1265.

Disclosure of Interests

None declared

A positive direct Coombs’ test in the absence of hemolytic anemia predicts high disease activity and poor renal response in systemic lupus erythematosus

We determined the clinical utility of the direct Coombs’ test in the absence of hemolytic anemia as an indicator of disease activity and therapeutic response in systemic lupus erythematosus (SLE). SLE patients without hemolytic anemia who visited our hospital from January 2016 to November 2016 were retrospectively evaluated with a direct Coombs’ test. Clinical features, including SLE disease activity index (SLEDAI), treatment and laboratory findings were analyzed. For patients with lupus nephritis, we additionally evaluated the cumulative complete renal response rate over one year after induction therapy. Among 182 patients evaluated, 10 (5.8%) patients had a positive direct Coombs’ test in the absence of hemolytic anemia. They had a higher SLEDAI ( p < 0.01), higher circulating immune complex levels ( p = 0.01), higher anti-DNA titers ( p < 0.01) and a lower complete renal response rate ( p = 0.03) compared with those who were negative. Multivariate analysis indicated that SLEDAI was an independent factor correlated with the direct Coombs’ test without hemolytic anemia (odds ratio 2.4, 95% confidence interval 1.66–4.98, p < 0.01). A positive direct Coombs’ test in the absence of hemolytic anemia may therefore represent a useful biomarker for assessing disease activity and therapeutic response.

Phase II study of medroxyprogesterone acetate plus metformin as a fertility-sparing treatment for atypical endometrial hyperplasia and endometrial cancer

BACKGROUND

Metformin, widely used in the treatment of type 2 diabetes mellitus, reduces the risk of cancer and relapse after treatment. Fertility-sparing treatment for endometrial cancer (EC) with progestin is associated with a high chance of disease regression, and the high relapse rate continues to be a problem. We assessed the efficacy of metformin in preventing recurrence after medroxyprogesterone acetate (MPA) as fertility-sparing treatment for atypical endometrial hyperplasia (AEH) and EC.

PATIENTS AND METHODS

This phase II study enrolled 17 patients with AEH and 19 patients with EC limited to the endometrium (age, 20-40 years). MPA (400 mg/day) and metformin (750-2250 mg/day) were administered for 24-36 weeks to achieve a complete response (CR). Metformin was administered until conception, even after MPA discontinuation. The primary end point was relapse-free survival (RFS) after remission. We analyzed all efficacy end points in the full analysis set.

RESULTS

The body mass index was ≥25 kg/m(2) in 27 patients (mean, 31 kg/m(2); range, 19-51 kg/m(2)), and the homeostasis model assessment for insulin resistance index was ≥2.5 in 24 patients (mean, 4.7; range, 0.7-21). Two patients showed progression at 12 weeks [6%; 95% confidence interval (CI) 2-18]. At 36 weeks, 29 (81%; 95% CI 65-90) patients achieved CR, and 5 (14%; 95% CI 6-29) patients achieved partial response. During a median follow-up of 38 months (range, 9-66 months) after remission, relapse was confirmed in three of the patients who had achieved CR (relapse rate, 10%). The 3-year estimated RFS rate was 89%. No patients experienced severe toxicity.

CONCLUSIONS

Metformin inhibited disease relapse after MPA therapy. The combination of metformin and MPA in EC treatment should be studied further.

TRIAL REGISTRATION NUMBER

UMIN 000002210.

Vascular endothelial growth factor as a predictive marker for POEMS syndrome treatment response: retrospective cohort study

OBJECTIVE

POEMS (polyneuropathy, organomegaly, endocrinopathy, M-protein and skin changes) syndrome is a rare multisystem disease characterised by plasma cell dyscrasia and overproduction of vascular endothelial growth factor (VEGF). VEGF is assumed to be useful in monitoring disease activity, because VEGF levels usually decrease after treatment. However, there is no study to investigate whether the extent of decrease in VEGF correlates with clinical outcome. We tested the predictive efficacy of serum VEGF levels in POEMS syndrome.

METHOD

This was an institutional review board approved retrospective observational cohort study of 20 patients with POEMS monitored regularly for more than 12 months (median follow-up, 87 months) after treatment onset using our prospectively accumulated database of POEMS from 1999 to 2015. Patients were treated by autologous peripheral blood stem cell transplantation or thalidomide administration. Serum VEGF was measured by ELISA. Outcome measures included clinical and laboratory findings and relapse-free survival.

RESULTS

Serum VEGF levels decreased rapidly after treatment, and stabilised by 6 months post treatment. Patients with normalised serum VEGF levels (<1040 pg/mL) at 6 months showed prolonged relapse-free survival (HR=12.81, 95% CI 2.691 to 90.96; p=0.0001) and greater later clinical improvement. The rate of serum VEGF reduction over the first 6 months post treatment correlated with increased grip strength, serum albumin levels, and compound muscle action potential amplitudes at 12 months.

CONCLUSIONS

Serum VEGF level at 6 months post treatment is a predicative biomarker for disease activity and prognosis in POEMS syndrome. Serum VEGF could be used as a surrogate endpoint for relapse-free survival or clinical or laboratory improvement of POEMS syndrome for clinical trials.

Overexpression of CXCR4 on circulating B cells in patients with active systemic lupus erythematosus

OBJECTIVES

To evaluate the roles of circulating B cells in the pathogenic process of systemic lupus erythematosus (SLE) by measuring the expression of chemokines and their receptors.

METHODS

Peripheral-blood mononuclear cells were obtained from 17 active, 21 inactive SLE patients, and 13 healthy controls. The expression of CXCR4, CXCR5, and CCR7 on CD19+ B cells was determined by flow cytometry, serum concentration of CXCL12 was measured by enzyme-linked immunosorbent assay, and the chemotactic responsiveness of B cells toward CXCL12 was evaluated. B or plasma cells expressing CXCR4 in renal biopsy specimens were detected using immnofluorescent staining.

RESULTS

Flow cytometric analysis revealed that expression level of CXCR4 on circulating B cells was significantly higher in patients with active disease than in those with inactive disease or controls. Serum CXCL12 concentration was not different between these groups. In addition, the migratory ability of B cells toward CXCL12 was enhanced in active SLE patients. Finally, CXCR4-expressing B cells were more frequently observed in the renal biopsy specimens of lupus nephritis.

CONCLUSIONS

Up-regulated CXCR4 expression on circulating B cells in active SLE may enhance their chemotactic response toward CXCL12, which may promote infiltration of these cells into inflamed renal tissue and contribute to the development of SLE.

Anti-signal recognition particle antibody in patients without inflammatory myopathy: a survey of 6180 patients with connective tissue diseases

OBJECTIVES

To clarify the prevalence of anti-signal recognition particle (anti-SRP) antibody in connective tissue diseases (CTDs) and investigate the clinical characteristics of patients without inflammatory myopathy.

METHOD

Sera from 6180 patients with CTD were examined by immunoprecipitation (IPP) assays, and the records of patients positive for anti-SRP antibody were reviewed retrospectively. The antibody against the 54-kDa protein of SRP (SRP54) was quantified by enzyme-linked immunosorbent assay (ELISA) in patients with anti-SRP antibody.

RESULTS

Of the 28 patients positive for anti-SRP antibody, nine (32.1%) did not have inflammatory myopathy. The clinical diagnoses and characteristics of those patients varied considerably. In patients with inflammatory myopathy, the index of anti-SRP54 was much higher than in those without myopathy (1.15 vs. 0.46; p = 0.036).

CONCLUSIONS

The prevalence of anti-SRP antibody was 0.5% in a cohort of Japanese patients with CTD, and one-third of them did not have inflammatory myopathy. Sera from patients with inflammatory myopathy recognized SRP54 more strongly than in those without myopathy.

Efficacy and safety of the dipeptidyl peptidase-4 inhibitor sitagliptin compared with α-glucosidase inhibitor in Japanese patients with type 2 diabetes inadequately controlled on sulfonylurea alone (SUCCESS-2): a multicenter, randomized, open-label, non-inferiority trial

We assessed the efficacy and safety of sitagliptin compared with α-glucosidase inhibitor (αGI) in 120 of Japanese patients with type 2 diabetes mellitus (T2DM) inadequately controlled on stable ≤2 mg/day glimepiride alone [mean hemoglobin A1c (HbA1c) 7.7%] by the randomized, active-controlled, non-inferiority trial. Patients were randomly assigned to receive additional sitagliptin or αGI for 24 weeks. The primary endpoint was change in HbA1c from baseline to week 12. After 12 weeks, sitagliptin reduced HbA1c by -0.44% (p < 0.001) relative to αGI. At 24 weeks, the reduction was almost identical between the groups (-0.091%, p = 0.47). Gastrointestinal disorders were more common with αGI than with sitagliptin, but only minor hypoglycaemia occurred in both groups at similar frequency. These data suggested that sitagliptin was not inferior to αGI for reduction of HbA1c in Japanese T2DM patients receiving glimepiride alone, and well tolerated with minimum risk of gastrointestinal symptoms and hypoglycaemia.

Circulating anti-double-stranded DNA antibody-secreting cells in patients with systemic lupus erythematosus: a novel biomarker for disease activity

Antibodies against double-stranded DNA (dsDNA) are widely used to diagnose systemic lupus erythematosus (SLE) and evaluate its activity in patients. This study was undertaken to examine the clinical utility of circulating anti-dsDNA antibody-secreting cells for evaluating SLE patients. Anti-dsDNA antibody-secreting cells quantified using an enzyme-linked immunospot assay were detected in the spleen, bone marrow and peripheral blood from MRL/ lpr but not in control BALB/c mice. Circulating anti-dsDNA antibody-secreting cells were detected in 29 (22%) of 130 patients with SLE, but in none of 49 with non-SLE connective-tissue disease or 18 healthy controls. The presence of circulating anti-dsDNA antibody-secreting cells was associated with persistent proteinuria, high SLE disease activity index and systemic lupus activity measures, and a high serum anti-dsDNA antibody titre measured with an enzyme-linked immunosorbent assay. The positive predictive value for active disease was 48% for circulating anti-dsDNA antibody-secreting cells versus 17% for serum anti-dsDNA antibodies. A prospective cohort of patients with circulating anti-dsDNA antibodies and inactive SLE showed that the cumulative disease flare-free rate was significantly lower in patients with than without circulating anti-dsDNA antibody-secreting cells ( p < 0.001). Circulating anti-dsDNA antibody-secreting cells are a useful biomarker for assessing disease activity in SLE patients.

Ultrastructural Cytochemical and Ultrastructural Morphological Differences Between Human Multinucleated Giant Cells Elicited by Wear Particles from Hip Prostheses and Artificial Ligaments at the Knee

The authors investigated the ultrastructural cytochemical features of multinucleated and mononuclear cells in periprosthetic tissues associated with bone resorption (osteolysis) and those in tissues adjoining failed artificial ligaments having no relation to bone resorption. Clinical specimens of granulation tissue of each type, respectively numbering 4 and 3, were stained for tartrate-resistant acid phosphatase (TRAP) reactions and examined by light and electron microscopy. Both periprosthetic granulation tissues and those adjoining artificial ligaments contained TRAP-positive multinucleated and mononuclear cells. Near joint prostheses, multinucleated cells, including some giant cells, showed TRAP activity and cytoplasmic features resembling osteoclasts, while others had features consistent with foreign-body giant cells, and still others showed degenerative changes. Near artificial ligaments, TRAP-positive multinucleated cells lacked osteoclastic features. At both sites, TRAP-positive multinucleated cells had phagocytised wear particles. TRAP-positive mononuclear cells at both sites also showed phagocytic cytoplasmic features, but not osteoclastic cytoplasmic features. Human mononuclear phagocytes and multinucleated giant cells induced by wear particles possess TRAP activity. Those multinucleated giant cells at sites of osteolysis developed osteoclastic cytoplasmic features and have a phagocytic function.

Similarities Between Giant Cell Tumor of Bone, Giant Cell Tumor of Tendon Sheath, and Pigmented Villonodular Synovitis Concerning Ultrastructural Cytochemical Features of Multinucleated Giant Cells and Mononuclear Stromal Cells

The authors investigated ultrastructural cytochemical features of multinucleated and mononuclear stromal cells in giant cell tumor of bone (GCTB), giant cell tumor of tendon sheath (GCTTS), and pigmented villonodular synovitis (PVNS). Specimens of each tumor, respectively numbering 4, 4, and 3, were stained for tartrate-resistant acid phosphatase (TRAP) reactions and examined with an electron microscope. In GCTB and GCTTS, multinucleated cells, including some relatively small giant cells, showed TRAP activity and cytoplasmic features characteristic of osteoclasts, and also sometimes abundant rough endoplasmic reticulum and siderosomes. A few giant cells with macrophage-like features and slight TRAP activity were demonstrated in GCCTS and PVNS. In each tumor type, mononuclear cells showing TRAP activity shared cytoplasmic features with osteoclast-like multinucleated giant cells, while some others had macrophage-like features, and still others were poorly differentiated; a few mononuclear cells showed cell-to-cell contact. Ultrastructural similarities of TRAP-positive mononuclear cells in the three tumor types, and those between TRAP-positive multinucleated cells in GCTB and GCTTS, suggest a common cell lineage capable of multinucleated giant cell formation in the 3 tumors, despite differing histogenesis.

Paravertebral neurinoma associated with aggressive intravertebral extension

Neurinomas are relatively common benign tumors thought to arise from nerve sheath cells. Although intraosseous neurinomas may destroy the bone, extraosseous neurinomas with extensive destruction and invasion of bone are considered rare. We present two unusual cases of a benign extraosseous neurinoma that extensively invaded the vertebral body through the nutrient canal.

Pulmonary vein and left atrial invasion by lung cancer: assessment by breath-hold gadolinium-enhanced three-dimensional MR angiography

PURPOSE

The purpose of this work was to evaluate the ability of breath-hold gadolinium-enhanced three-dimensional (3D) MR angiography to assess the invasion of the pulmonary vein and the left atrium by lung cancer.

METHOD

Gadolinium-enhanced 3D MR angiography was performed in 20 consecutive patients with lung cancer.

RESULTS

At two sites with left atrial invasion shown by MR angiography, associated partial resection of the left atrium was performed. At five sites with invasion of the proximal pulmonary vein within 1.5 cm from the left atrium on MR, partial resection of the left atrium was performed at one site, and the pulmonary vein was resected at the intrapericardial portion at three sites. At two sites with invasion of the proximal pulmonary vein 1.5 cm more distal to the left atrium, the pulmonary vein was resected at the extrapericardial portion.

CONCLUSION

Breath-hold gadolinium-enhanced 3D MR angiography is suitable for assessing invasion of the pulmonary vein and the left atrium by lung cancer.

Low-dose cisplatin and 5-fluorouracil in combination can repress increased gene expression of cellular resistance determinants to themselves

The synergistic mechanism of cisplatin (CDDP) and 5-fluorouracil (5-FU) in combination remains unclear, despite its substantial antitumor activity, which has been demonstrated clinically. To clarify the mechanism(s), we determined the sensitivity or resistance factors to either drug in seven gastrointestinal cancer cell lines and then analyzed the altered gene expression after different exposures to CDDP and 5-FU. At the basal gene expression level, glutathione S-transferase pi (GSTpi) expression correlated with the observed resistance to CDDP, whereas dihydropyrimidine dehydrogenase (DPD) and multidrug resistance-associated protein (MRP) expression was related to 5-FU resistance. GSTpi, DPD, and MRP expression increased in response to the respective drug, but they also increased in response to the other drug as well. Additionally, 5-FU revealed a drastically increased thymidylate synthase (TS) gene expression in 5-FU-resistant cells. However, the increasing actions of CDDP and 5-FU on GSTpi, DPD, MRP, and TS expression varied according to the exposure time, concentration, and schedule. A low concentration of CDDP (1 microg/ml, 30 min) followed by 5-FU (0.5 microg/ml, 72 h) was found to cause a less increased expression of DPD, MRP, GSTpi, and TS than either drug alone, thus resulting in synergistic cytotoxicity in 5-FU-resistant COLO201 and CDDP-resistant HCC-48 cells. The sequential combination of CDDP and 5-FU inhibited the growth of human normal renal proximal tubule cells by less than 20%. Low concentrations of CDDP followed by continuous exposure to 5-FU can repress increased gene expression related to both drug resistances, thereby being synergistically cytotoxic in human gastrointestinal cancer cells.

MRI artifacts of metallic stents derived from imaging sequencing and the ferromagnetic nature of materials

In vitro and in vivo studies were performed to assess the optimum materials and imaging methods for metallic stents by conducting an in vitro investigation of MRI artifacts arising during imaging by several representative imaging methods using various types of stents and by clarifying the differences occurring with different metals and imaging sequences. We also examined the use of MRCP and MRA in evaluating luminal patency within stented biliary tracts and blood vessels in vivo. In vitro study showed either no artifacts or very slight artifacts created by titanium stents, however, marked image distortion was created by a stainless steel stent. Using SE instead of GRE sequences can minimize these artifacts. Echo planar imaging (EPI) produced severe susceptibility artifacts, resulting in unsatisfactory images. In vitro and in vivo studies indicated that MRCP was an effective method for follow-up studies of bile duct stents, but that MRA is quite limited as a method of follow-up study for currently available vascular stents.

Regulatory network of mitomycin C action in human colon cancer cells

A network composed of activation and inactivation pathways to regulate mitomycin C (MMC) action is suggested to exist in human cancer cells. COLO201 colon cancer cells were stably transfected with human NQO1 cDNA that encodes NAD(P)H:quinone oxidoreductase (DT-diaphorase, DTD), and a clonal cell line with about 57-fold elevated DTD activity was obtained. Northern analysis revealed that expression of the NADPH:cytochrome P450 reductase (P450 reductase) gene was decreased in the transfectant, COLO201/NQO1, associated with the increase of NQO1 expression. Biochemical characterization of the cells showed a significant increase of the glutathione (GSH) content concomitantly with the decrease of the P450 reductase activity. As a result of these coordinated modulations, sensitivity of COLO201/NQO1 to MMC was not increased as compared to the parent cells. Analyses of inhibition by specific inhibitors of DTD, P450 reductase and glutathione S-transferase (GST) in 5 human colon cancer cell lines including the transfectant showed that DTD and P450 reductase play significant roles in MMC activation in cells with sufficiently high DTD activity and with marginal DTD activity, respectively. In contrast, GST appeared to participate in MMC inactivation in cells with a high level of GST activity. These results indicated that DTD, P450 reductase, GSH and GST may act together compensatively or competitively, depending on their levels in cells, to determine the cellular sensitivity to MMC.

[Breath-hold MR cholangiopancreatography with 2D and 3D-FASE sequence at 0.5 tesla: evaluation based on measurements of signal intensity ratio and contrast-to-noise ratio]

Single-slice 2D-FASE (more than 2 cm) and 3D-FASE images proved to be reliable techniques by which to create high-resolution MRCP images at 0.5 T. In particular, 3D-FASE sequence can provided MIP and its thin source images with sufficient SIR and CNR of the images, which are useful to evaluate detailed structures. Using 3D-FASE sequence, even the non-dilated pancreatobiliary system can frequently be demonstrated because each source image retains satisfactory SIR and CNR of the images due to 3D acquisition and is not affected by motion artifacts of any kind. The most important problem for 3D-FASE sequence is that view-to view amplitude modulation errors may persist, though gradient moment errors can be reduced because of no actual motion during acquisition, resulting in degraded the MIP images due to the different positions of the source images in a few patients with inconstant respiration.

Diagnosis of anomalous pancreaticobiliary junction: value of magnetic resonance cholangiopancreatography

BACKGROUND

Anomalous pancreaticobiliary junction (a long common channel), with or without congenital choledochal cyst, is frequently associated with biliary tract carcinoma. We assessed the diagnostic value of magnetic resonance cholangiopancreatography (MRCP) for patients with anomalous pancreaticobiliary junction (PBJ).

METHODS

In 159 adult patients with pancreatobiliary disease, breath-hold (1 to 18 seconds) MRCP was performed according to a half-Fourier acquisition single-shot turbo spin-echo sequence. In all patients the length of the common channel demonstrated by MRCP was compared with that demonstrated by endoscopic retrograde cholangiopancreatography. In 11 patients with anomalous PBJ (the common channel > or = 15 mm on endoscopic retrograde cholangiopancreatography), the diagnostic accuracy of MRCP for associated biliary diseases was evaluated.

RESULTS

No complications were encountered in performing MRCP. On MRCP, the length of the common channel was calculated to be 15 mm or longer in nine (82%) of 11 patients with anomalous PBJ. In patients with normal PBJ, MRCP identified PBJ with the channel measuring 0 mm in length. MRCP allowed detailed visualization of congenital choledochal cyst (all seven patients) but failed to depict carcinoma (one patient) and mucosal hyperplasia (five patients) of the gallbladder.

CONCLUSIONS

MRCP is a noninvasive and accurate imaging method for diagnosing anomalous PBJ and congenital choledochal cyst.

Diagnosis of anomalous pancreaticobiliary junction: value of magnetic resonance cholangiopancreatography

BACKGROUND

Anomalous pancreaticobiliary junction (a long common channel), with or without congenital choledochal cyst, is frequently associated with biliary tract carcinoma. We assessed the diagnostic value of magnetic resonance cholangiopancreatography (MRCP) for patients with anomalous pancreaticobiliary junction (PBJ).

METHODS

In 159 adult patients with pancreatobiliary disease, breath-hold (1 to 18 seconds) MRCP was performed according to a half-Fourier acquisition single-shot turbo spin-echo sequence. In all patients the length of the common channel demonstrated by MRCP was compared with that demonstrated by endoscopic retrograde cholangiopancreatography. In 11 patients with anomalous PBJ (the common channel > or = 15 mm on endoscopic retrograde cholangiopancreatography), the diagnostic accuracy of MRCP for associated biliary diseases was evaluated.

RESULTS

No complications were encountered in performing MRCP. On MRCP, the length of the common channel was calculated to be 15 mm or longer in nine (82%) of 11 patients with anomalous PBJ. In patients with normal PBJ, MRCP identified PBJ with the channel measuring 0 mm in length. MRCP allowed detailed visualization of congenital choledochal cyst (all seven patients) but failed to depict carcinoma (one patient) and mucosal hyperplasia (five patients) of the gallbladder.

CONCLUSIONS

MRCP is a noninvasive and accurate imaging method for diagnosing anomalous PBJ and congenital choledochal cyst.

Improvement of MR cholangiopancreatography at .5 T: three-dimensional half-averaged single-shot fast spin echo with multi-breath-hold technique

The purpose of this study was to determine the advantage of a three-dimensional (3D) single-shot fast-spin-echo (SSFSE) sequence to obtain MR cholangiopancreatography (MRCP) with a .5-T MR unit by comparison with a two-dimensional (2D) SSFSE sequence. MRCP with 2D-SSFSE and with 3D-SSFSE with 128 echo train lengths was performed on 15 volunteers and 38 patients with pancreatobiliary disease using a .5-T MR unit. For maximum intensity projection (MIP) reconstruction, the section thickness of source images was 4 mm in the 2D-SSFSE and 3 mm in the 3D-SSFSE. 3D volume data in 3D-SSFSE were obtained using repeated short breath-hold of 2 seconds for every repetition time throughout the examination. The image quality, duct conspicuity, signal-intensity ratio (SIR), and contrast-to-noise ratio (CNR) were evaluated. In 23 of the patients who underwent both MRCP and direct cholangiopancreatography (endoscopic retrograde cholangiopancreatography [ERCP]/percutaneous transhepatic cholangiography [PTC]), a comparison between these two modalities was also conducted. The image quality of the MIP image with 3D-SSFSE (49 of 53, 92.5% graded excellent or good) was superior to that with 2D-SSFSE (31 of 53, 58.4%). Duct conspicuity, SIR, and CNR were significantly higher with 3D-SSFSE than with 2D-SSFSE. 3D-SSFSE also showed a stronger relationship with the ERCP/PTC findings compared to 2D-SSFSE. 3D-SSFSE provided satisfactory quality, SIR, and CNR of MRCP images, even when a .5-T MR unit was used, because the breath-hold technique used during 3D data sampling minimized all types of motion effects.

Reversible intracranial changes in eclampsia demonstrated by MRI and MRA

CT and MRI allow visualization of eclampsia changes in the brain. Once case with reversible changes is reported.

The effects of high dose of parathyroid hormone on fetal osteoclasts and their precursors in vivo: an ultrastructural-cytochemical study

BACKGROUND

It is not well known how the immediate precursors of osteoclast develop into osteoclasts in the fetus. This ultrastructural-cytochemical study was designed to clarify the formation process of the osteoclasts and their increased activities in the fetal mouse limb buds after administration of high dose parathyroid hormone (PTH).

METHODS

Twenty-four or forty-eight hours after the high doses of PTH were injected into amniotic fluid of the pregnant C3H mice, the femoral limb buds of embryos were dissected out. Tartrate-resistant acid phosphatase (TRAP) reactions were performed while preparing specimens for electron microscopy.

RESULTS

Both control and PTH-given preosteoclasts and osteoclasts exhibited TRAP-positivities in dense bodies and vesicles. As effects of PTH, a binucleated preosteoclast of tandem fashion was observed. More osteoclastic hyperactivities were observed in the diaphyseal bone marrow. An osteoclast with a large cytoplasm exhibited two sets of clear zones and ruffled borders. Some osteoclasts demonstrated prominent amoeboid figures, while other osteoclasts developed large cytoplasmic vacuoles, which contained pieces of calcified chondroid bars.

CONCLUSIONS

Our results revealed the progression of maturation from young preosteoclasts to osteoclasts. An existence of a peculiar binucleated preosteoclasts suggested one of the processes for multinucleation of the osteoclast. Quite remarkable osteoclastic hyperactivities were obviously the effects of high dose PTH. Our results also indicated the endophagocytic ability of the osteoclast. How PTH affected the osteoclasts and their precursors in the diaphyseal bone marrow can be speculated.

[Clinical application of magnetic resonance angiography for coronary arteries: correlation with conventional angiography and evaluation of imaging time]

Magnetic resonance angiography (MRA) of the coronary arteries is a particularly difficult task because of the small size of the vessels and cardio-respiratory motion. The authors describe a method of performing of ultrafast MRA of the coronary arteries with a standard MR system and body coil. Each image was obtained within a single breath hold by "segmented Turbo FLASH" sequences using an electrocardiography gate. Clinical application was performed in 20 patients with ischemic heart disease, and a comparison was made with conventional coronary angiography. The imaging time was shortened significantly by our methods. The diagnosis was made by at least two different images to avoid false positives. The results indicated a good correlation between MRA and conventional angiography.

[Experimental study of flow rates in microcatheters using various kinds of contrast materials: comparison of imaging capability by iodine delivery rates]

In order to establish the optimal injection technique for abdominal digital subtraction angiography (DSA), flow rate measurement was performed under various combinations of all the currently available iodinated contrast materials with two types of coaxial microcatheters. In vitro study was done utilizing a plastic model of the abdominal aorta with the tip of the catheter positioned at the presumed proper hepatic artery. A total of 20ml of contrast material was injected by a pressure injector at a rate of 3 ml/sec at 300 or 600 psi, and actual flow volume was measured. Imaging capability was evaluated by calculating iodine delivery rates (IDRs). IDRs were highest in iopamidol 300 mgI/ml and iomeperol 300 mgI/ml, nonionic monomeric contrast materials of medium concentration. The results suggest that the best quality DSA images with injection to the proper hepatic artery using a coaxial microcatheter can be obtained with nonionic monomeric contrast materials of medium concentration.

[Calcified false channel wall in aortic dissection]

Chest radiographs and computed tomographic images of 110 patients with chronic aortic dissection were retrospectively reviewed. Among these, calcification of false channel wall was observed in 12 cases (about 10%). Stanford type A dissection was noted in 5 cases and type B in 7 cases. Calcified false channel wall may closely simulate intimal calcification of atherosclerotic aneurysm on chest radiographs and sometimes even on CT. Careful observation of CT images with and without contrast enhancement is helpful to correctly identify the site of calcifications in the false channel wall, true channel wall, and intimal flap in the individual cases. In 3 cases calcification was present mainly in the false channel wall with no or only minimal calcification in the true channel wall. These cases may suggest that the endothelialized false channel lumen may develop atheromatous changes much more rapidly than the true lumen. According to advances in surgical and medical treatment of acute aortic dissection, radiologists may encounter cases of chronic aortic dissection with increasing frequency. Full recognition of this potential pitfall in the diagnosis of aortic dissection is important to avoid confusion.

Atelectasis as a complication of tracheobronchial stent therapy

Although insertion of expandable metallic stents in cases of tracheobronchial stenosis is effective as palliation for respiratory distress, the potential risk of creating obstructive atelectasis and aggravating symptoms of patients should be noted. The authors' experience in two cases is presented, and prevention of this potential complication is discussed.

In vitro characterization of lung cancers by the use of 1H nuclear magnetic resonance spectroscopy of tissue extracts and discriminant factor analysis

Using proton magnetic resonance spectroscopy (1H MRS) spectra were obtained in vitro from extracts of four types of lung cancer (squamous cell, adenocarcinoma, large cell, small cell) and normal lung. The hydrophilic phase of the chloroform/methanol-water extracts yielded several distinct peaks. Among them the peak areas for cholines, creatines, glycine, and alanine, and their ratios were calculated and used as parameters to characterize different lung tissues. The ratios, cholines/alanine and glycine/alanine, were significantly (P < 0.001 to P < 0.05) higher for the normal lung than lung cancers. Creatines/glycine and creatines/cholines generally provided good discrimination (P < 0.001 to P < 0.05) between any two types of lung cancer. When data were further analyzed by discriminant factor analysis, there was 81.5 to 90.7% accuracy in predicting between normal lung and each cancer type, or among the four types of lung cancer. These results suggested that 1H MRS might be useful as an adjunct modality in the differential diagnosis of lung cancers.

Hypophosphatemic osteomalacia in von Recklinghausen neurofibromatosis

Skeletal lesions are not uncommon in von Recklinghausen neurofibromatosis. Most of them are considered to be dysplastic in nature. Association of osteomalacia or rickets with neurofibromatosis has been documented only rarely. Reported herein is a 40-year-old woman with known von Recklinghausen neurofibromatosis who presented with bone pain, multiple pseudofractures, marked increase in osteoid by bone biopsy, and hypophosphatemia with renal phosphate wasting. Treatment with oral phosphate and vitamin D was effective. A survey of the literature revealed that 34 similar cases have been reported in the past. Although the exact pathogenetic mechanism remains to be determined, osteomalacia in neurofibromatosis appears to be distinct from more common dysplastic skeletal affections of this disease, being characterized by later onset in adulthood as a rule, renal phosphate loss with hypophosphatemia, multiple pseudofractures in typical cases, and response to treatment with pharmacological dose of vitamin D with or without phosphate supplement.

Hydration of fibrinogen, fibrin, and fibrin degradation product (FDP) as estimated by nuclear magnetic resonance (NMR) spectroscopy

The relaxation times (T1 and T2) of water proton in nuclear magnetic resonance (NMR) were measured with solutions containing bovine fibrinogen (Fbg), fibrin degradation products (FDP) and with fibrin-gel (Gel), at varying protein concentrations (0.7-70 mg/ml). Both T1 and T2 declined exponentially with increasing protein concentration. At a protein concentration of 35 mg/ml, the T1 of Fbg, Gel and FDP were 2.32, 2.12 and 2.82 s and the T2 values were 0.35, 0.17 and 0.70, respectively. The relaxation times for the control samples (0.2 M borate buffer) were 3.41 (T1) and 2.28 (T2). When the relaxation rates (the inverse of T1 and T2), R1 and R2 were plotted against the protein concentration, there were positive linear correlations between them. Using the slopes of the plots, the hydration value of each protein was calculated. The hydration value (g of H2O/g of protein) was 0.24 for Fbg, 0.34 for Gel and 0.14 for FDP.

The origin of the osteoclast

The origin of the osteoclast remains controversial even though investigations using light microscopy, tissue culture, electron microscopy, microcinematography, autoradiography, parabiosis, quail chick nuclear markers, giant lysosomal markers in beige mice, Y chromosomes, bone marrow cell culture, and monoclonal antibodies have been performed since its discovery. Concepts of the origin of the osteoclast have been changing. The classic concept was that the osteoclast originated from connective tissue cells. Others hypothesized that it originated from mature hematopoietic cells, particularly from monocyte or macrophage cells. A recent concept proposed an origin from hematopoietic stem cells. The hematopoietic stem cell was believed to differentiate into two cell lineages: one of monocytes and the other of preosteoclasts. The authors' concept, based on experimental observations as well as alternate interpretations stemming from experimental reports of other researchers, proposes an origin from local, nonhematopoietic, possibly perivascular mesenchymal cells. However, the relationship of the hematopoietic stem cells to perivascular mesenchymal cells in the periosteum at an early stage of enchondral ossification is still not well known. Therefore, the origin of the osteoclast also remains uncertain.

Histogenesis of alveolar soft part sarcoma. An immunohistochemical and biochemical study

In order to clarify the histogenesis of alveolar soft part sarcoma (ASPS), an immunohistochemical and biochemical study was performed on three cases. The immunohistochemical study indicated the presence of actin, desmin, vimentin, and Z-protein in all cases. On the other hand, intermediate filaments other than desmin and vimentin were not detected immunohistochemically. The presence of desmin and Z-protein strongly suggests the myogenic character of this tumor. As to whether ASPS shows striated muscle differentiation or smooth muscle differentiation, the immunohistochemical absence of myoglobin in the three cases suggests that the tumor does not differentiate in the direction of striated muscle. However, biochemical assay of subunits of enolase revealed significantly high amounts of beta-enolase, which is known as a marker for striated muscle, in all three cases. The determined values--735, 426, and 584 ng/mg of protein --are indicative of striated muscle differentiation. In addition, the immunohistochemical study of all cases revealed the presence of beta-enolase in tumor cells. These data definitely show the myogenic character and rhabdomyoblastic differentiation of ASPS.

Investigation of the origin of the osteoclast by use of transplantation on chick chorioallantoic membrane

In recent years, it has become generally accepted that osteoblasts and osteoclasts are derived from separate stem cell lines: the osteoblasts from mesenchymal cells, and the osteoclasts from cells of hematopoietic origin. Principal evidence for this belief comes from experimental approaches, such as autoradiography, parabiosis, quail-chick nuclear markers, lysosomal markers in beige mice, and so forth. However, the problem remains unsolved. For further investigation of osteoclast origin, three experimental designs were employed: (1) six-day quail limb buds were directly implanted into chick chorioallantoic membrane; (2) viable or devitalized Dunn osteosarcomas were implanted onto chorioallantoic membrane; and (3) six-day quail limb buds in diffusion chambers were implanted onto chorioallantoic membrane by use of exogenous parathyroid hormone (PTH) stimulation. In these experiments, osteoblasts and osteoclasts were identified from host (chorioallantoic membrane) and implant (quail limb bud). Limb buds within diffusion chambers formed osteoclasts in response to PTH despite no blood circulation or bone marrow formation. These data indicate that the mesenchyme (perichondrium) plays an important role. Either osteoclast mononuclear precursors have migrated from hematopoietic sources to the perichondrium before transplantation of the limb buds or mesenchymal cells of developing bone can form osteoclasts. Thus, the origin of the osteoclasts should still be considered an unsettled question.

Cellular differentiation of epithelioid sarcoma. An electron-microscopic, enzyme-histochemical, and immunohistochemical study

For the purpose of clarifying cellular differentiation of epithelioid sarcoma, studies based on various methods were performed. Enzyme histochemical studies showed that epithelioid sarcoma tumor cells have characteristics intermediate between epithelial cells and the large plump cells of synovial sarcoma-incomplete epithelial differentiation. For alkaline phosphatase and adenosine triphosphatase particularly, positive cells and negative cells coexisted, as in the large plump cells of synovial sarcoma. Immunohistochemical studies for alpha 1-antitrypsin, alpha 1-antichymotrypsin, vimentin, and keratin also showed that epithelioid sarcoma tumor cells are very similar to the large plump cells of synovial sarcoma and have incomplete epithelial differentiation. For example, the examinations of serial sections and double staining methods revealed that keratin-positive cells are always vimentin-positive in epithelioid sarcoma and in the monophasic area of synovial sarcoma. Electron-microscopically, bundles of intermediate filaments and filopodia toward the intercellular lumen were observed, as in the monophasic area of synovial sarcoma. The results of enzyme-histochemical and immunohistochemical studies of non-neoplastic synovial lining cells, performed here for the first time, are also discussed.

Alveolar soft part sarcoma. An elaboration of a three-dimensional configuration of the crystalloids by digital image processing

As an initial step to elucidate the nature of the unique characteristics of the crystalloids of alveolar soft part sarcoma, a three-dimensional model of the crystalloids was prepared by digital image analysis of electron micrographs by computer. It was revealed that occult periodicities are present at two intervals, 60 A and 380 A, in the filamentous structure of the crystalloid; and it was also revealed by the observation of each cross-section that two globular substances with a diameter of 60 A are arranged in a dumbbell pattern in each filamentous structure. The model prepared based on these data showed the double strands crossing each other at intervals of 380 A, each of which consists of successive arrangement of the globular substances with a diameter of 60 A. This structure is clearly similar to that of actin. The similarities and differences between these results and the well-known studies of the organization of naturally occurring actin bundles are discussed.