179 research outputs found
A new application of the SFDA-staining method to assessment of the freezing tolerance in leaves of alpine plants
For the first time, this study used 5- (6-) sulfofluorescein diacetate (SFDA), a fluorescent product in plant cells converted by esterase activity to fluorescein-5- (and 6-) sulfonic acid (FSA), to assess the freezing tolerance of leaf cells. We were able to readily distinguish living and dead cells, and detect differences in freezing tolerance among five alpine plants using the SFDA-staining method. We also compared this method with two conventional methods, the electrolyte leakage test and fluorescein diacetate (FDA) staining method. The electrolyte leakage test often over- or underestimated freezing injury. With the uninjured control samples, the FDA-staining method failed to stain all leaf cells, while the SFDA-staining method stained almost 100%. From these results, we concluded that SFDA-staining is a more convenient, accurate and reproducible method for analyses of freezing tolerance
Sh3bp2 Gain-Of-Function Mutation Ameliorates Lupus Phenotypes in B6.MRL-Faslpr Mice
SH3 domain-binding protein 2 (SH3BP2) is an adaptor protein that is predominantly expressed in immune cells, and it regulates intracellular signaling. We had previously reported that a gain-of-function mutation in SH3BP2 exacerbates inflammation and bone loss in murine arthritis models. Here, we explored the involvement of SH3BP2 in a lupus model. Sh3bp2 gain-of-function (P416R knock-in; Sh3bp2KI/+) mice and lupus-prone B6.MRL-Faslpr mice were crossed to yield double-mutant (Sh3bp2KI/+Faslpr/lpr) mice. We monitored survival rates and proteinuria up to 48 weeks of age and assessed renal damage and serum anti-double-stranded DNA antibody levels. Additionally, we analyzed B and T cell subsets in lymphoid tissues by flow cytometry and determined the expression of apoptosis-related molecules in lymph nodes. Sh3bp2 gain-of-function mutation alleviated the poor survival rate, proteinuria, and glomerulosclerosis and significantly reduced serum anti-dsDNA antibody levels in Sh3bp2KI/+Faslpr/lpr mice. Additionally, B220+CD4-CD8- T cell population in lymph nodes was decreased in Sh3bp2KI/+Faslpr/lpr mice, which is possibly associated with the observed increase in cleaved caspase-3 and tumor necrosis factor levels. Sh3bp2 gain-of-function mutation ameliorated clinical and immunological phenotypes in lupus-prone mice. Our findings offer better insight into the unique immunopathological roles of SH3BP2 in autoimmune diseases
AI for Exercise-Induced Pulmonary Hypertension
Background: Stress echocardiography is an emerging tool used to detect exercise-induced pulmonary hypertension (EIPH). However, facilities that can perform stress echocardiography are limited by issues such as cost and equipment.
Objective: We evaluated the usefulness of a deep learning (DL) approach based on a chest X-ray (CXR) to predict EIPH in 6-min walk stress echocardiography.
Methods: The study enrolled 142 patients with scleroderma or mixed connective tissue disease with scleroderma features who performed a 6-min walk stress echocardiographic test. EIPH was defined by abnormal cardiac output (CO) responses that involved an increase in mean pulmonary artery pressure (mPAP). We used the previously developed AI model to predict PH and calculated PH probability in this cohort.
Results: EIPH defined as ΔmPAP/ΔCO >3.3 and exercise mPAP >25 mmHg was observed in 52 patients, while non-EIPH was observed in 90 patients. The patients with EIPH had a higher mPAP at rest than those without EIPH. The probability of PH based on the DL model was significantly higher in patients with EIPH than in those without EIPH. Multivariate analysis showed that gender, mean PAP at rest, and the probability of PH based on the DL model were independent predictors of EIPH. A model based on baseline parameters (age, gender, and mPAP at rest) was improved by adding the probability of PH predicted by the DL model (AUC: from 0.65 to 0.74; p = 0.046).
Conclusion: Applying the DL model based on a CXR may have a potential for detection of EIPH in the clinical setting
Deep learning approach for analyzing chest x-rays to predict cardiac events in heart failure
Background: A deep learning (DL) model based on a chest x-ray was reported to predict elevated pulmonary artery wedge pressure (PAWP) as heart failure (HF).
Objectives: The aim of this study was to (1) investigate the role of probability of elevated PAWP for the prediction of clinical outcomes in association with other parameters, and (2) to evaluate whether probability of elevated PAWP based on DL added prognostic information to other conventional clinical prognostic factors in HF.
Methods: We evaluated 192 patients hospitalized with HF. We used a previously developed AI model to predict HF and calculated probability of elevated PAWP. Readmission following HF and cardiac mortality were the primary endpoints.
Results: Probability of elevated PAWP was associated with diastolic function by echocardiography. During a median follow-up period of 58 months, 57 individuals either died or were readmitted. Probability of elevated PAWP appeared to be associated with worse clinical outcomes. After adjustment for readmission score and laboratory data in a Cox proportional-hazards model, probability of elevated PAWP at pre-discharge was associated with event free survival, independent of elevated left atrial pressure (LAP) based on echocardiographic guidelines (p < 0.001). In sequential Cox models, a model based on clinical data was improved by elevated LAP (p = 0.005), and increased further by probability of elevated PAWP (p < 0.001). In contrast, the addition of pulmonary congestion interpreted by a doctor did not statistically improve the ability of a model containing clinical variables (compared p = 0.086).
Conclusions: This study showed the potential of using a DL model on a chest x-ray to predict PAWP and its ability to add prognostic information to other conventional clinical prognostic factors in HF. The results may help to enhance the accuracy of prediction models used to evaluate the risk of clinical outcomes in HF, potentially resulting in more informed clinical decision-making and better care for patients
Autoimmunity to citrullinated type II collagen in rheumatoid arthritis
The production of autoantibodies to citrullinated type II collagen and the citrullination of type II collagen were analyzed in rheumatoid arthritis. Autoantibodies to citrullinated type II collagen were detected in 78.5% of serum samples from 130 rheumatoid arthritis patients. Autoantibodies to native noncitrullinated type II collagen were detected in 14.6% of serum samples, all of which were positive for anti-citrullinated type II collagen antibodies. Serum samples were also positive for anti-citrullinated type II collagen antibodies in 1 of 31 systemic lupus erythematosus patients and 2 of 55 patients with osteoarthritis of the knee. In contrast, sera samples from 24 systemic sclerosis patients, 21 dermatomyositis/polymyositis patients, 21 ankylosing spondylitis patients, and 18 psoriatic arthritis patients were all negative for anti-citrullinated type II collagen antibodies. Anti-citrullinated type II collagen antibodies and fragments of citrullinated type II collagen were found in the synovial fluid obtained from affected knee joints of 15 rheumatoid arthritis patients. Moreover, anti-citrullinated type II collagen antibodies were isolated from the synovium of affected knee joints in 8 rheumatoid arthritis patients using antigen/antibody immunocomplex dissociation buffer but not by using standard buffers. These findings indicate that autoantibodies that react with citrullinated type II collagen are specifically produced and that immunocomplexes composed of fragments of citrullinated type II collagen and autoantibodies are deposited in the inflamed articular synovium in rheumatoid arthritis patients. Assaying for the presence of anti-citrullinated type II collagen antibodies may therefore be useful for diagnosing rheumatoid arthritis, and the deposition of these immunocomplexes in the articular synovium may be involved in pathogenesis
Short-term outcomes of mirogabalin in patients with peripheral neuropathic pain: a retrospective study
Background
Mirogabalin, which is approved for the treatment of peripheral neuropathic pain in Japan, is a ligand for the α2δ subunit of voltage-gated calcium channels. Both pregabalin and mirogabalin act as nonselective ligands at the α2δ-1 and α2δ-2 subunits. Mirogabalin has a unique binding profile and long duration of action. Pregabalin has been reported to produce intolerable adverse effects in some patients. This study investigated outcomes associated with mirogabalin administration in patients with peripheral neuropathic pain who ceased treatment with pregabalin.
Methods
We retrospectively assessed peripheral neuropathic pain using the neuropathic pain screening questionnaire (NeP score) in 187 patients (58 men, 129 women) who were treated with mirogabalin. All patients had switched from pregabalin to mirogabalin due to lack of efficacy or adverse events. Differences in the treatment course (i.e., numeric rating scale (NRS) scores) were compared using one-way analysis of variance with Bonferroni post hoc tests.
Results
The mean age of the patients was 72.3 years (range, 30–94 years), and the mean duration of disease was 37 months (range, 3–252 months). After treatment with mirogabalin for 1 week, NRS scores significantly decreased compared with baseline and continued to decrease over time. After 8 weeks, NRS scores improved by ≥ 30% from baseline in 113 patients (69.3%). Twenty-four patients (12.8%) stopped mirogabalin treatment due to adverse events. Somnolence (26.7%), dizziness (12.3%), edema (5.9%), and weight gain (0.5%) were noted as adverse events of mirogabalin.
Conclusions
The results of this investigation indicate that mirogabalin is safe and effective for reducing peripheral neuropathic pain
Intraductal Lipid-Rich Carcinoma of the Breast with a Component of Glycogen-Rich Carcinoma
We report a rare case of intraductal lipid-rich carcinoma of the breast with a component of glycogen-rich carcinoma. An impalpable tumor that was revealed by mammography and magnetic resonance imaging was excised. Histologic examination showed vacuolated neoplastic cells in the mammary ducts, and electron microscopy confirmed lipid droplets in the cytoplasm. The coexistence of glycogen-rich carcinoma was shown. Lipid-rich carcinoma that is coexistent with glycogen-rich carcinoma is rare, and most lipid-rich carcinomas are invasive. Intraductal lipid-rich carcinoma is difficult to detect without echography or mammography
Citizen science "Thundercloud Project" -- multi-point radiation measurements of gamma-ray glows from accelerated electrons in thunderstorms
38th International Cosmic Ray Conference (ICRC2023), 26 July - 3 August, 2023, Nagoya, JapanIt has been a long-standing question whether cosmic rays promote the triggering of lightning and how cosmic-ray air showers interact with the electric field of thunderclouds. The strong electric field in the thunderclouds accelerates electrons to the relativistic regime, of which seed electrons are thought to be supplied from cosmic-ray air shower. Such relativistic electrons emit bremsstrahlung photons in gamma rays, which have been detected by on-ground measurements called gamma-ray glows. Low-altitude winter thunderstorm in Japan provides an ideal environment for observations of gamma-ray glows. We newly launched the citizen science ``Thundercloud Project" to construct a multi-point radiation mapping campaign for glows from winter thunderstorms around Kanazawa, Japan. We developed a new handy radiation monitor and shipped about 60 detectors to citizen supporters. The radiation data are stored in the microSD cards in the detectors, and a part of them is remotely sent to the web server so that researchers and supporters can watch the real-time data. In addition, an automatic alert is sent to public Twitter from the server when a glow is detected. The purpose of this project is (1) to characterize the methodological condition of electron acceleration, (2) to investigate whether accelerated relativistic electrons can enhance the chance of the initiation of lightning discharges, and (3) to find a new way of the citizen science to join in the cutting edge science in the physics field. Here we report this growing citizen science project and examples of successful gamma-ray glow observations. Our first scientific result from this citizen science project was published in Tsurumi et al., GRL 2023, where we reported lightning discharges started in or near the electron acceleration site of a gamma-ray glow
SH3BP2 Deficiency Ameliorates Murine Systemic Lupus Erythematosus
Background: The adaptor protein Src homology 3 domain-binding protein 2 (SH3BP2) is widely expressed in immune cells. It controls intracellular signaling pathways. The present study was undertaken to investigate the role of SH3BP2 in a murine systemic lupus erythematosus model. Methods: For the lupus model, we used Faslpr/lpr mice. Clinical and immunological phenotypes were compared between Faslpr/lpr and SH3BP2-deficient Faslpr/lpr mice. Splenomegaly and renal involvement were assessed. Lymphocyte subsets in the spleen were analyzed by flow cytometry. To examine the role of SH3BP2 in specific cells, B cell-specific SH3BP2-deficient lupus mice were analyzed; T cells and bone marrow-derived dendritic cells and macrophages were analyzed in vitro. Results: SH3BP2 deficiency significantly reduced lupus-like phenotypes, presented as splenomegaly, renal involvement, elevated serum anti-dsDNA antibody, and increased splenic B220+CD4−CD8− T cells. Notably, SH3BP2 deficiency in B cells did not rescue the lupus-like phenotypes. Furthermore, SH3BP2 deficiency did not substantially affect the characteristics of T cells and macrophages in vitro. Interestingly, SH3BP2 deficiency suppressed the differentiation of dendritic cells in vitro and reduced the number of dendritic cells in the spleen of the lupus-prone mice. Conclusions: SH3BP2 deficiency ameliorated lupus-like manifestations. Modulating SH3BP2 expression could thus provide a novel therapeutic approach to autoimmune diseases
妊娠を契機に血小板減少を来たし,子宮内胎児死亡に至った全身性エリテマトーデス及び抗リン脂質抗体症候群の一例
抗リン脂質抗体症候群は,抗リン脂質抗体が産生されることで血栓症を主体とする病態を引き起こす自己免疫疾患である.動静脈血栓症に加え,習慣性流産,早産,妊娠高血圧症候群,胎児発育遅延,胎児機能不全などの妊娠合併症を高率に引き起こすとされている.また患者のうち約半数は全身性エリテマトーデスが併存していると言われている.我々は妊娠を契機に血小板減少を来たし,子宮内胎児死亡に至った全身性エリテマトーデス及び抗リン脂質抗体症候群の症例を経験した. 患者は20歳代女性,未経妊未経産.5年前に全身性エリテマトーデス及び抗リン脂質抗体症候群と診断された.プレドニゾロンとタクロリムス,アザチオプリンによる免疫抑制療法及び低用量アスピリン療法を開始され,数年間に渡りプレドニゾロン5mg/ 日+タクロリムス3mg/ 日+アザチオプリン50mg/ 日で病態は安定していた.妊娠を契機にプレドニゾロン10mg/ 日の単独治療に切り替えたが,徐々に血小板減少が進行してきたため入院し,プレドニゾロン30mg/ 日への増量及びタクロリムス3mg/ 日を再開した.また血栓予防治療として,低用量アスピリンに加えヘパリン療法を開始した.しかし妊娠16週5日で子宮内胎児死亡が判明したため,血栓予防治療を中止し児の娩出に至った. 抗リン脂質抗体症候群合併妊娠は,周産期管理に慎重を要する例も存在することを念頭に置き,特にハイリスク症例に対しては妊娠成立前から産婦人科と連携して治療にあたる必要がある. Antiphospholipid syndrome is an autoimmune disease characterized by episodes of recurrent thrombosis. This syndrome is associated with not only recurrent arteriovenous thrombosis but also recurrent pregnancy loss, premature birth, pregnancyinduced hypertension, and fetal growth restriction. It has been reported that systemic lupus erythematosus coexists with antiphospholipid syndrome in as many as about 50% of patients. We report a case of intrauterine fetal death (IUFD) following thrombocytopenia in a patient with systemic lupus erythematosus and antiphospholipid syndrome. A woman in her 20s had difficulty conceiving and had been diagnosed as having systemic lupus erythematosus and antiphospholipid syndrome 5 years earlier. She was started on immunosuppressive therapy with prednisolone 5 mg/day, tacrolimus 3 mg/day, and azathioprine 50 mg/day, with low-dose aspirin therapy. Her disease was stable for several years. Thrombopenia gradually developed after treatment was changed to prednisolone 10 mg/day during pregnancy. She was admitted to hospital and treatment was started with prednisolone 30 mg/day, tacrolimus 3 mg/day, and heparin therapy in addition to low-dose aspirin therapy. However, IUFD was detected at a gestational age of 16 weeks 5 days, so we discontinued thromboprophylaxis treatment and administered a therapeutic abortion. In patients with antiphospholipid syndrome who need meticulous perinatal management, it is important to consult with the obstetrics and gynecology specialists before proceeding with a potentially high-risk pregnancy
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