Quantitative evaluation model of variable diagnosis for chest X-ray images using deep learning

The purpose of this study is to demonstrate the use of a deep learning model in quantitatively evaluating clinical findings typically subject to uncertain evaluations by physicians, using binary test results based on routine protocols. A chest X-ray is the most commonly used diagnostic tool for the detection of a wide range of diseases and is generally performed as a part of regular medical checkups. However, when it comes to findings that can be classified as within the normal range but are not considered disease-related, the thresholds of physicians' findings can vary to some extent, therefore it is necessary to define a new evaluation method and quantify it. The implementation of such methods is difficult and expensive in terms of time and labor. In this study, a total of 83,005 chest X-ray images were used to diagnose the common findings of pleural thickening and scoliosis. A novel method for quantitatively evaluating the probability that a physician would judge the images to have these findings was established. The proposed method successfully quantified the variation in physicians' findings using a deep learning model trained only on binary annotation data. It was also demonstrated that the developed method could be applied to both transfer learning using convolutional neural networks for general image analysis and a newly learned deep learning model based on vector quantization variational autoencoders with high correlations ranging from 0.89 to 0.97.

Interaction between type 2 diabetes polygenic risk and physical activity on cardiovascular outcomes

AIM

The beneficial effects of exercise on reducing the risk of cardiovascular disease are established. However, the potential interaction between genetic risk for type 2 diabetes and physical activity on cardiovascular outcomes remains elusive. We aimed to investigate the effect of type 2 diabetes genetic risk-physical activity interaction on cardiovascular outcomes in individuals with diabetes.

METHODS

Using the UK Biobank cohort, we investigated the effect of type 2 diabetes genetic risk-physical activity interaction on 3-point and 4-point major adverse cardiovascular events (MACE), in 25,701 diabetic participants. We used a polygenic risk score for type 2 diabetes (PRS_T2D) as a measure of genetic risk for type 2 diabetes.

RESULTS

We observed significant interaction between PRS_T2D and physical activity on cardiovascular outcomes (3-point MACE: P trend for interaction = 0.0081; 4-point MACE: P trend for interaction = 0.0037). Among participants whose PRS_T2D was in the first or second quartile, but not in the third or fourth quartile, each 10 metabolic equivalents (METs) hours per week of physical activity decreased the risk of 3-point or 4-point MACE. Furthermore, restricted cubic spline analysis indicated that intense physical activity (>80 METs hours per week, which was self-reported by 12.7% of participants) increased the risk of cardiovascular outcomes among participants whose PRS_T2D was in the fourth quartile. Subgroup analysis suggested that negative impact of intense physical activity was observed only in non-insulin users.

CONCLUSIONS

The beneficial effect of physical activity on cardiovascular outcomes were disappeared among those with high genetic risk for type 2 diabetes.

Anti-neurofascin 155 Antibody-positive Neuropathy in a Human Immunodeficiency Virus-infected Patient

Human immunodeficiency virus (HIV)-associated neuropathy is a common complication of HIV infection and has several clinical subtypes. HIV-associated chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is a demyelinating neuropathy whose clinical features are known to differ from those of CIDP in the HIV-uninfected population. We herein report a case of CIDP in an HIV-infected patient who was finally diagnosed with anti-neurofascin 155 (NF155) antibody-positive neuropathy. The clinical features, including clinical findings and therapeutic responses, were typical of paranodal antibody-mediated neuropathy. To our knowledge, this is the first case of anti-NF155 antibody-associated neuropathy in an HIV-infected patient.

NFIA in adipocytes reciprocally regulates mitochondrial and inflammatory gene program to improve glucose homeostasis

Adipose tissue is central to regulation of energy homeostasis. Adaptive thermogenesis, which relies on mitochondrial oxidative phosphorylation (Ox-Phos), dissipates energy to counteract obesity. On the other hand, chronic inflammation in adipose tissue is linked to type 2 diabetes and obesity. Here, we show that nuclear factor I-A (NFIA), a transcriptional regulator of brown and beige adipocytes, improves glucose homeostasis by upregulation of Ox-Phos and reciprocal downregulation of inflammation. Mice with transgenic expression of NFIA in adipocytes exhibited improved glucose tolerance and limited weight gain. NFIA up-regulates Ox-Phos and brown-fat-specific genes by enhancer activation that involves facilitated genomic binding of PPARγ. In contrast, NFIA in adipocytes, but not in macrophages, down-regulates proinflammatory cytokine genes to ameliorate adipose tissue inflammation. NFIA binds to regulatory region of the Ccl2 gene, which encodes proinflammatory cytokine MCP-1 (monocyte chemoattractant protein-1), to down-regulate its transcription. CCL2 expression was negatively correlated with NFIA expression in human adipose tissue. These results reveal the beneficial effect of NFIA on glucose and body weight homeostasis and also highlight previously unappreciated role of NFIA in suppressing adipose tissue inflammation.

Waning cellular immune responses and predictive factors in maintaining cellular immunity against SARS-CoV-2 six months after BNT162b2 mRNA vaccination

Several clinical trials have shown that the humoral response produced by anti-spike antibodies elicited by coronavirus disease 2019 (COVID-19) vaccines gradually declines. The kinetics, durability and influence of epidemiological and clinical factors on cellular immunity have not been fully elucidated. We analyzed cellular immune responses elicited by BNT162b2 mRNA vaccines in 321 health care workers using whole blood interferon-gamma (IFN-γ) release assays. IFN-γ, induced by CD4 + and CD8 + T cells stimulated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike epitopes (Ag2), levels were highest at 3 weeks after the second vaccination (6 W) and decreased by 37.4% at 3 months (4 M) and 60.0% at 6 months (7 M), the decline of which seemed slower than that of anti-spike antibody levels. Multiple regression analysis revealed that the levels of IFN-γ induced by Ag2 at 7 M were significantly correlated with age, dyslipidemia, focal adverse reactions to full vaccination, lymphocyte and monocyte counts in whole blood, Ag2 levels before the second vaccination, and Ag2 levels at 6 W. We clarified the dynamics and predictive factors for the long-lasting effects of cellular immune responses. The results emphasize the need for a booster vaccine from the perspective of SARS-CoV-2 vaccine-elicited cellular immunity.

A Comparative Study of Periodontal Health Status between International and Domestic University Students in Japan

BACKGROUND

In our previous study, international university students showed a significantly higher dental caries morbidity rate than domestic students. On the other hand, the periodontal health status of international university students has not been clarified yet. In this study, we compared the periodontal health status of international and domestic university students in Japan.

METHODS

We conducted a retrospective review of the clinical data of the university students that visited a dental clinic in the division for health service promotion at a university in Tokyo for screening between April 2017 and March 2019. Bleeding on probing (BOP), calculus deposition and probing pocket depth (PPD) were investigated.

RESULTS

The records of 231 university students (79 international and 152 domestic university students) were analyzed; 84.8% of international students were from Asian countries (n = 67). The international university students showed a higher percentage of BOP than domestic students (49.4% and 34.2%, respectively: p < 0.05) and they showed more extensive calculus deposition (calculus grading score [CGS]) than domestic university students (1.68 and 1.43, respectively: p < 0.01), despite no significant difference in PPD.

CONCLUSIONS

The current study shows that international university students have poorer periodontal health than domestic students in Japan, even though the result might include many uncertainties and possible biases. To prevent severe periodontitis in the future, regular checkups and thorough oral health care are essential for the university students, especially those from foreign countries.

Nutrient infusion evoked magnetic resonance imaging signal in the human hypothalamus

BACKGROUND

The hypothalamus receives ingested nutrient information via ascending gut-related projections and plays a significant role in the regulation of food intake. Human neuroimaging studies have observed changes in the activity or connectivity of the hypothalamus in response to nutrient ingestion. However, previous neuroimaging studies have not yet assessed differences in temporal changes of hypothalamic responses to various nutrients in humans. Thus a repeated measures functional magnetic resonance imaging (fMRI) study using 30-min scans was designed to examine differences in hypothalamic responses to various nutrients.

METHODS

In this study, 18 healthy adults (mean age, 22.4 years; standard deviation, 4.8; age range, 19-39 years; 11 males and seven females) underwent fMRI sessions. On the day of each session, one of the four solutions (200 ml of monosodium glutamate, glucose, safflower oil emulsion, or saline) was administered to participants while fMRI scanning.

RESULTS

Infused amino acid and glucose, but not lipid emulsion, increased lateral hypothalamic responses as compared to a saline infusion ([x, y, z] = [4, -4, -10], z = 2.96). In addition, only hypothalamic responses to saline, but not those to the infusion of other nutrients, elicited a subjective sensation of hunger.

CONCLUSION

These findings suggest that lateral hypothalamic responses to ingested nutrients may mediate homeostatic sensations in humans.

The association between adverse reactions and immune response against SARS-CoV-2 spike protein after vaccination with BNT162b2 among healthcare workers in a single healthcare system: a prospective observational cohort study

Adverse reactions after vaccination with COVID-19 mRNA vaccines are common; however, the association between adverse reactions and humoral responses is uncertain. To determine whether humoral immune responses after BNT162b2 vaccine administration were associated with local and systemic adverse reactions, we conducted a prospective observational cohort study in a single tertiary referral center. Healthcare workers who received the first dose of BNT162b2 vaccine were recruited. SARS-CoV-2 anti-spike IgG antibody titers were measured three weeks after the second dose and information about adverse reactions after vaccination was collected. Among the 887 participants, 641 (72.3%) were women. The median age was 38 (range, 22–74) years. All but one showed anti-spike IgG levels well above the cutoff, with a median level of 13,600 arbitrary units/mL. Overall, 800 (92.2%) participants reported some reactions after the first dose and 822 (96.3%) after the second dose. Significantly more participants reported systemic reactions after the second dose than after the first dose (P < .01), and 625 (73.6%) reported that reactions were stronger after the second dose. Factors positively associated with elevation of anti-spike IgG levels were history of asthma (24% higher if present, P = .01) and stronger reactions after the second dose (19% higher if experienced, P = .02). The majority of participants showed good humoral responses and reported some adverse reactions after vaccination. Anti-spike IgG levels were significantly higher if adverse reactions after the second dose were stronger than those after the first dose. These findings may help inform current and future vaccine recipients.

Systemic Disorders Closely Associated with Malocclusion in Late Adolescence: A Review and Perspective

Oral diseases such as dental caries and periodontal disease are reported to be associated with various systemic diseases such as heart disease, respiratory disease, diabetes, rheumatism, and metabolic syndrome, thus increasing the importance of prevention and early treatment [...].

Interpretations of SARS-CoV-2 IgM and IgG antibody titers in the seroepidemiological study of asymptomatic healthy volunteers

Introduction

The usefulness of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody tests in asymptomatic individuals has not been well validated, although they have satisfied sensitivity and specificity in symptomatic patients. In this study, we investigated the significance of IgM and IgG antibody titers against SARS-CoV-2 in the serum of asymptomatic healthy subjects.

Methods

From June 2020, we recruited 10,039 participants to the project named the University of Tokyo COVID-19 Antibody Titer Survey (UT-CATS), and measured iFlash-SARS-CoV-2 IgM and IgG (YHLO IgM and IgG) titers in the collected serum. For the samples with increased IgM or IgG titers, we performed additional measurements using Elecsys Anti-SARS-CoV-2 Ig (Roche total Ig) and Architect SARS-CoV-2 IgG (Abbott IgG) and investigated the reactivity to N, S1, and receptor binding domain (RBD) proteins.

Results

After setting the cutoff value at 5 AU/mL, 61 (0.61%) were positive for YHLO IgM and 104 (1.04%) for YHLO IgG. Few samples with elevated YHLO IgM showed reactivity to S1 or RBD proteins, and IgG titers did not increase during the follow-up in any samples. The samples with elevated YHLO IgG consisted of two groups: one reacted to S1 or RBD proteins and the other did not, which was reflected in the results of Roche total Ig.

Conclusions

In SARS-CoV-2 seroepidemiological studies of asymptomatic participants, sufficient attention should be given to the interpretation of the results of YHLO IgM and IgG, and the combined use of YHLO IgG and Roche total Ig might be more reliable.

Changing trends in lipid profile and biomarkers of renal function and bone metabolism before and after switching from tenofovir disoproxil fumarate to tenofovir alafenamide: a prospective observational study

Background

Antiretrovirals, including tenofovir, can suppress human immunodeficiency virus (HIV) infection but cannot completely eradicate it. Patients with HIV infection are administered antiretroviral drugs over a long term; thus, managing consequent adverse drug reactions, such as renal dysfunction and bone mineral loss, is important. Currently, highly sensitive biomarkers that can detect adverse drug reactions early have not been well studied.

Methods

This single-center, prospective, observational study explored changes in the biomarkers of renal function, bone metabolism, and lipid profile before and after switching from tenofovir disoproxil fumarate (TDF) to tenofovir alafenamide (TAF) in patients with HIV infection.

Results

All 31 enrolled patients had been treated with antiretrovirals for more than 5 years. The rate of proteinuria decreased significantly after starting TAF-containing antiretroviral regimen. The urinary liver-type fatty acid binding protein (L-FABP)/creatinine ratio was significantly decreased at 3 and 6 months after switching to TAF compared with that before switching to TAF (− 0.5 μg/g Cr at 3 months, and − 0.8 μg/g Cr at 6 months; p < 005 for both at 3 and 6 months). The urinary N-terminal telopeptide (NTx)/creatinine ratio decreased over the study period, and the ratios were significantly different between 3 and 6 months (− 11 nmol/mmol Cr at 3 months, − 15.2 nmol/mmol Cr at 6 months; p = 0.0069 at 3 months, p < 0.0001 at 6 months). Low density lipoprotein-cholesterol level significantly increased at 3 (+ 26 mg/dL) and 6 months (+ 13 mg/dL) compared with that at the baseline (p < 0.0001).

Conclusions

Switching from TDF to TAF decreased the levels of renal and bone biomarkers, such as urinary L-FABP and NTx, but increased low density lipoprotein-cholesterol levels. Future studies should evaluate if these biomarkers, such as urinary L-FABP and NTx, truly detect serious adverse drug reactions early.

Awareness of Malocclusion Is Closely Associated with Allergic Rhinitis, Asthma, and Arrhythmia in Late Adolescents

Background: Oral infectious diseases are typified by dental caries and periodontal diseases and are known to be associated with various systemic diseases. However, clear associations between occlusal disorders and systemic diseases have not yet been established. We investigated the association between an awareness of malocclusion and common diseases in late adolescence. Methods: We retrospectively reviewed the data of mandatory medical questionnaires that are a legal requirement of the freshman medical checkup. We collected the data of all the students who completed the questionnaires between April 2017 and 2019. The data were analyzed using the χ² test and multivariate analysis was performed with a binomial logistic regression model. Results: The subjects were 9098 students aged 17–19 (mean age 18.3 years). The rate of awareness of malocclusion was 2.14% (195 out of 9098 eligible subjects; 160 males and 35 females). These students had significantly greater rates of allergic rhinitis, asthma, and arrhythmia (p < 0.001). Multivariate analysis revealed significant rates of allergic rhinitis (odds ratio [OR] 2.184, 95% confidence interval [CI]: 1.468–3.250, p < 0.001), asthma (OR 1.843, 95%CI: 1.153–2.945, p = 0.011), and arrhythmia (OR 2.809, 95%CI: 1.083–7.288, p = 0.034) among students with an awareness of malocclusion. Conclusion: We identified close associations between an awareness of malocclusion and systemic diseases including allergic rhinitis, asthma, and arrhythmia in the late adolescent population. These results reinforce the associations between malocclusion and allergic rhinitis and asthma, as well as providing novel insight into the association of malocclusion and arrhythmia. However, further research is necessary to confirm the associations and explore the mechanisms underlying these associations.

Close Associations of Gum Bleeding with Systemic Diseases in Late Adolescence

BACKGROUND

Though it is well known that periodontal diseases are associated with various systemic diseases in adults, the associations in late adolescents have not been adequately elucidated. We investigated the association between gum bleeding (a major symptom of periodontal diseases) and common systemic diseases in late adolescents: allergic, respiratory, and otorhinolaryngologic diseases.

METHODS

We conducted a retrospective review of the mandatory medical questionnaires administered as a part of legally required freshman medical checkup between April 2017 and April 2019 at the University of Tokyo. Among the total of 9376 sets of responses, 9098 sets from students aged less than 20 were analyzed. An χ2 test and univariate and multivariate binomial logistic regression analyses were performed using SAS ver. 9.4. A value of p < 0.05 was accepted as significant.

RESULTS

According to the questionnaire data, 3321 students (36.5%; 2780 males and 541 females) responded that they experienced gum bleeding whenever they brushed their teeth. These students had significantly higher incidence rates of otitis media/externa and asthma/cough-variant asthma (p = 0.001 and p = 0.006, respectively). The results of the multivariate analysis showed significant rates of the following complications among these students: (1) otitis media/externa (odds ratio (OR) 1.691; 95% confidence interval (CI): 1.193-2.396; p = 0.003), (2) asthma/cough-variant asthma (OR 1.303; 95% CI: 1.091-1.556; p = 0.003), and (3) male gender (OR 1.536; 95% CI: 1.337-1.765; p < 0.001).

CONCLUSIONS

Gum bleeding was closely associated with otitis media/externa and asthma in late adolescents. Our study reinforces new evidence about the association between periodontal diseases and asthma, and it reveals a novel and close association between gum bleeding and otitis media/externa.

Dasatinib Is an Effective Treatment for Angioimmunoblastic T-cell Lymphoma

Recurrent hotspot (p.Gly17Val) mutations in RHOA encoding a small GTPase, together with loss-of-function mutations in TET2 encoding an epigenetic regulator, are genetic hallmarks of angioimmunoblastic T-cell lymphoma (AITL). Mice expressing the p.Gly17Val RHOA mutant on a Tet2-null background succumbed to AITL-like T-cell lymphomas due to deregulated T-cell receptor (TCR) signaling. Using these mice to investigate therapeutics for AITL, we found that dasatinib, a multikinase inhibitor prolonged their survival through inhibition of hyperactivated TCR signaling. A phase I clinical trial study of dasatinib monotherapy in 5 patients with relapsed/refractory AITL was performed. Dasatinib was started at a dose of 100 mg/body once a day and continued until days 10-78 (median day 58). All the evaluable patients achieved partial responses. Our findings suggest that AITL is highly dependent on TCR signaling and that dasatinib could be a promising candidate drug for AITL treatment. SIGNIFICANCE: Deregulated T-cell receptor signaling is a critical molecular event in angioimmunoblastic T-cell lymphoma and can be targeted with dasatinib.

Diagnostic accuracy of urine dipstick for proteinuria category in Japanese workers

BACKGROUND

Urine dipstick tests are often used to evaluate proteinuria during health checkups. We examined the dipstick's accuracy in assessing the proteinuria levels among Japanese workers.

METHODS

We assessed subjects aged ≥ 18 years who had a health checkup at the University of Tokyo in 2016 or 2017 (n = 5383). Proteinuria was stratified by urine protein-to-creatinine ratio (PCR): A1, < 150 mg/gCre; A2, 150-499 mg/gCre; and A3, ≥ 500 mg/gCre. The accuracy of a dipstick result of ± or higher to detect a PCR level of ≥ A2 was examined. We compared changes in dipstick results and PCR level in 136 subjects evaluated twice with a median interval of 119 days.

RESULTS

The subjects' mean age was 40 years, and half were women. The dipstick results were - in 94.9%, ± in 4.1%, and ≥ 1 + in 1.0%. The PCR level was A1, A2, A3 in 98.6%, 1.2%, and 0.2% of the subjects, respectively. The sensitivity, specificity, and positive and negative predictive values of a ± or higher dipstick result to detect A2 or higher were 66.2%, 95.6%, 17.5%, and 99.5%, respectively. Among the 136 subjects examined twice, 134 (98.5%) had no change in PCR level (A1 in all cases) despite a decrease or increase in dipstick results.

CONCLUSION

Urine dipstick results of ± or above had a high specificity but low sensitivity and positive predictive value to detect PCR proteinuria of A2 or higher. Confirmation by quantitative protein measurement should be recommended for individuals at high risk of chronic kidney disease.

Pleural thickening on screening chest X-rays: a single institutional study

Although pleural thickening is a common finding on routine chest X-rays, its radiological and clinical features remain poorly characterized. Our investigation of 28,727 chest X-rays obtained from annual health examinations confirmed that pleural thickening was the most common abnormal radiological finding. In most cases (92.2%), pleural thickening involved the apex of the lung, particularly on the right side; thus, it was defined as a pulmonary apical cap. Pleural thickening was more common in males than in females and in current smokers or ex-smokers than in never smokers. The prevalence increased with age, ranging from 1.8% in teenagers to 9.8% in adults aged 60 years and older. Moreover, pleural thickening was clearly associated with greater height and lower body weight and body mass index, suggesting that a tall, thin body shape may predispose to pleural thickening. These observations allowed us to speculate about the causative mechanisms of pleural thickening that are attributable to disproportionate perfusion, ventilation, or mechanical forces in the lungs.

The incidence and risk factors of asymptomatic primary spontaneous pneumothorax detected during health check-ups

BACKGROUND

Patients with primary spontaneous pneumothorax (PSP) usually complain of sudden-onset dyspnea and pleuritic chest pain. However, asymptomatic PSP has been incidentally detected on chest X-rays. In this study, we analyzed the incidence, characteristics, risk factors, and prognosis of asymptomatic PSP detected during regular medical check-ups in university students.

METHODS

In this study, 101,709 chest X-rays were performed during medical check-ups for students at the University of Tokyo between April 2011 and March 2016. Among them, 43 cases of asymptomatic PSP (0.042%) were detected. We calculated the lung collapse rate of pneumothorax using Kircher's method. We also analyzed risk factors associated with asymptomatic PSP using characteristics inspected in medical check-ups.

RESULTS

The incidence of asymptomatic PSP was significantly higher in men than in women (0.050% vs 0.018%). Multivariate analysis revealed an association of younger age, greater height, lower body mass index, and greater height growth per year with an increased risk of asymptomatic PSP in male students. Mild lung collapse (<10%) was present in 22 of 43 students with asymptomatic PSP; among these, eight students eventually underwent an invasive therapy.

CONCLUSIONS

The prevalence of asymptomatic PSP among university students was as high as 0.042%. In addition to known risk factors for conventional PSP, greater height growth was a risk factor for asymptomatic PSP. Careful follow-up is very important because a considerable number of patients with mild lung collapse eventually require an invasive medical procedure.

Abstract 249: Dose-response Relationship Between the Risk of Vasovagal Syncope and Body Mass Index

Vasovagal syncope (VVS) is the most common type of syncope with associated fatigue, nausea, abdominal discomfort, and dizziness. VVS usually resolves uneventfully, but sometimes leads to head trauma or other injuries. Blood tests are the most commonly performed medical tests, and prevention of VVS associated with blood sample collection is important from a medical or public health perspective.

We investigated the association between body mass index (BMI), systolic blood pressure (SBP), estimated circulating blood volume (CBV), and the risk of VVS in healthy young adults undergoing blood tests, and attempted to quantify potential dose-response relations and identify high-risk populations.

We examined 18,888 students entering the University of Tokyo between 2011 and 2016, who had a normal electrocardiogram, no structural heart disease, and no previous syncopal loss of consciousness. VVS was defined as syncope occurring before, during, or immediately after blood collection, with symptoms including weakness, pallor, cold sweats, nausea, vomiting, a lower systolic blood pressure or pulse rate compared with baseline, and need for assistance from a physician without any sequelae. Occurrence of VVS was confirmed by medical staff. CBV was calculated according to Nadler’s method.

The subjects had a mean age of 19±1 years and 19% (n=3522) were women. Mean BMI, SBP, and CBV were 21.0±2.9 kg/m2, 121±12 mmHg, and 4.4±0.4 L for men, and were 19.8±2.3 kg/m2, 108±11 mmHg, and 3.3±0.3 L for women, respectively.

VVS was diagnosed in 0.63% of the subjects (n=119) (19% women). By dose-response analysis, lower BMI showed a non-linear association with a significantly higher risk of VVS in men (p for non-linearity<0.001). Compared with a BMI of 22 kg/m2, the risk of VVS increased markedly at a BMI of 20 (OR 1.52; 95%CI 1.02-2.27) and increased further at a BMI of 18.5 (2.35; 1.41-3.92). Similarly, compared with the median SBP (120 mmHg), lower SBP showed a non-linear association with a higher risk of VVS (110 mmHg: OR 1.46, 95%CI 1.11-1.91; 100 mmHg: 2.51, 1.57-4.02; and 90 mmHg: 4.41, 1.91-10.2) (p for non-linearity=0.04). There was a negative linear correlation between CBV and VVS (P for non-linearity=0.43) in men. Lower CBV was associated with a higher risk of VVS. However, there were no significant correlations of these parameters in women. Also, there were no significant association between VVS risk and other covariates.

We demonstrated that lower BMI and SBP showed a J-curve association with the risk of VVS in men. Low BMI, SBP, and CBV are useful predictors for primary prevention of VVS. Providing advice on preventive methods such as counter-pressure maneuvers might be beneficial for high-risk persons, especially those who are “underweight” or have “hypotension”.

Catheter-related bloodstream infection caused by Kodamaea ohmeri: A case report and literature review

Kodamaea ohmeri is a rare yeast pathogen that has recently emerged as an important cause of fungemia in immunocompromised patients. However, appropriate therapy for this infection remains unclear. We report a case of catheter-related blood stream infection caused by K. ohmeri in a 58-year-old patient who improved after removal of the central venous catheter and administration of micafungin. Considering the antibiotic susceptibility of this pathogen and reviewing literature, echinocandins may be the first choice for an empiric therapy for this pathogen.

Scedosporium prolificans Endocarditis: Case Report and Literature Review

Scedosporium prolificans, a hyaline filamentous fungus, is widely distributed in the environment and is currently an emerging human pathogen, especially among immunocompromised patients. However, S. prolificans endocarditis is rare. We herein report a case of S. prolificans endocarditis in a 64-year-old patient with breast cancer in complete remission for 30 years after chemotherapy and radiation treatment who was not cured. Susceptibility testing showed resistance to all antifungal drugs, except echinocandin. A review of the literature revealed 10 cases of S. prolificans endocarditis; of these, only one involved an immunocompetent host with no risk factors and only two patients survived. In order to improve the mortality rate, it is necessary to establish rapid diagnostic methods and efficient therapeutic approaches.

A pathologically proven case of adult-onset HIV-related lymphocytic interstitial pneumonia with acute exacerbation treated with steroid and antiretroviral therapy

Lymphocytic interstitial pneumonia (LIP) is a rare opportunistic illness in human immunodeficiency virus (HIV)-infected adults, although it is relatively common among HIV-infected children. Most adult cases have been reported in African and Afro-Caribbean patients and few cases have been reported from Asia. Acute exacerbation of HIV-related LIP has not been well described. Here we report a pathologically proven case of acute exacerbation of adult-onset HIV-related LIP. The patient was an African immigrant living in Japan who presented with chronic dyspnea and diffuse bilateral pulmonary infiltrates. His clinical, radiological, and pathological findings were consistent with those of LIP. After a diagnostic surgical lung biopsy, his hypoxemia and pulmonary infiltrates exacerbated rapidly over a few days, although his condition had not progressed during the previous year. LIP may be an important differential diagnosis among adult patients in Asian countries, especially patients of non-Asian ethnicity.

Detection of the G17V RHOA mutation in angioimmunoblastic T-cell lymphoma and related lymphomas using quantitative allele-specific PCR

Angioimmunoblastic T-cell lymphoma (AITL) and peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS) are subtypes of T-cell lymphoma. Due to low tumor cell content and substantial reactive cell infiltration, these lymphomas are sometimes mistaken for other types of lymphomas or even non-neoplastic diseases. In addition, a significant proportion of PTCL-NOS cases reportedly exhibit features of AITL (AITL-like PTCL-NOS). Thus disagreement is common in distinguishing between AITL and PTCL-NOS. Using whole-exome and subsequent targeted sequencing, we recently identified G17V RHOA mutations in 60–70% of AITL and AITL-like PTCL-NOS cases but not in other hematologic cancers, including other T-cell malignancies. Here, we establish a sensitive detection method for the G17V RHOA mutation using a quantitative allele-specific polymerase chain reaction (qAS-PCR) assay. Mutated allele frequencies deduced from this approach were highly correlated with those determined by deep sequencing. This method could serve as a novel diagnostic tool for 60–70% of AITL and AITL-like PTCL-NOS.

Hypouricemic effect and safety of febuxostat used for prevention of tumor lysis syndrome

Purpose

We evaluated the efficacy and safety of febuxostat, a non-purine xanthine oxidase inhibitor, used for prevention of hyperuricemia associated with tumor lysis syndrome (TLS).

Methods

Records of adult patients with newly diagnosed or relapsed hematologic malignancies who received febuxostat within 7 days before initiation of chemotherapy were retrieved retrospectively at a single institute. The changes in serum uric acid levels from before and 7 days after initiation of febuxostat were evaluated and compared with the historical control group of patients who received allopurinol. We also evaluated non-hematological adverse events during the study period.

Results

A total of 78 patients’ records were analyzed, 38 in the febuxostat group and 39 in the allopurinol group. There were no significant differences in the incidence of treatment failure, defined as development of clinical TLS or receiving rasburicase, between the febuxostat and allopurinol group (5.2% vs 5.1%, P>0.99). The mean serum uric acid levels were significantly decreased, compared to the baseline (5.6 ± 2.1 mg/dL), at 7 days after initiation of febuxostat (3.1 ± 1.5 mg/dL, last observation carried forward, P<0.001). There were no statistically significant differences in the percent change in the serum uric acid levels between the 40 mg/day febuxostat and the 300 mg/day allopurinol groups (P = 0.57). Grade 3–4 liver dysfunctions were observed in both the febuxostat and allopurinol groups, without significant differences in incidence between the two groups (2.6% vs 5.1%, P>0.99). Neither gout flare nor skin rash occurred in any patients.

Conclusions

Febuxostat is feasible for prevention of hyperuricemia associated with TLS.

Clostridium difficile flagellin stimulates toll-like receptor 5, and toxin B promotes flagellin-induced chemokine production via TLR5

AIMS

Clostridium difficile is an important pathogen in nosocomial infections. Although C. difficile toxins are considered to be major virulence factors, pathogenesis of C. difficile associated diseases remains to be determined. In this study, we investigated whether C. difficile flagellin is involved in the pathogenesis of C. difficile-associated diseases.

MAIN METHODS

C. difficile flagellin was extracted from bacterial body by using a combination of ultracentrifugation and low speed centrifugation. Extracted C. difficile flagellin was added to HEK293T cells transiently transfected with pUNO-mcs (empty vector) or pUNO-hTLR5, and NF-kappaB activation was compared by a dual-luciferase assay. The amount of C. difficile flagellin-induced inflammatory mediators such as interleukin-8 and CCL20 was measured by ELISA assay in the culture media of intestinal epithelial cell lines, HT29 cells and Caco-2 cells. Flagellin induced phosphorylation of p38 mitogen-activated protein kinase was examined by Western blotting analysis in Caco-2 cells. The amount of C. difficile flagellin-induced inflammatory mediators in the presence, or absence of C. difficile toxin B was also measured by ELISA assay.

KEY FINDINGS

C. difficile flagellin induced activation of NF-kappaB in HEK293T cells via toll-like receptor 5. C. difficile flagellin also induced activation of p38 mitogen-activated protein kinase, and promoted the production of interleukin-8 and CCL20 in intestinal epithelial cells via toll-like receptor 5. Pretreatment with toxin B enhanced flagellin-induced cytokine productions.

SIGNIFICANCE

Our results indicate that toxin B promotes flagellin-induced activation of intestinal epithelial cells, and that C. difficile flagellin may play a role in the occurrence of C. difficile-associated diseases.

Relation Between Blood Pressure Estimated by Pulse Wave Velocity and Directly Measured Arterial Pressure

Hypertension is the strongest risk factor in cardiac and cerebrovascular diseases among the Japanese. Even daily variations in blood pressure may become a risk, and repeated blood pressure measurement is recommended. Conventional Ambulatory Blood Pressure Monitoring (ABPM), however,may cause discomfort to examinees because they have to have their arms compressed and carry the monitor itself. The number of ABPMmeasurements is limited to about 1 every 15–30 minutes. We therefore attempted, working with medical and engineering teams, to develop a wearable blood pressure sensor that would place less burden on examinees, be less influenced by physical movement, and be usable for continuous blood pressure measurement. We then examined the clinical practicality of the sensor. We modified the existing Moens-Korteweg blood-pressure equation and developed a new systolic blood pressure calculation system that used electrocardiography and ear-lobe pulse waves because the ear lobe would receive little influence from physical movement. We chose three clinical cases from among intensive care unit subjects. We not only estimated their blood pressure using the systemwe developed but also measured arterial pressure directly with an intravascular catheter to see how estimated blood pressure followed actual changes in blood pressure and to evaluate the accuracy of estimated blood pressure. When systolic blood pressure estimated by using the pulse wave velocity method was compared with direct blood pressure measurement, we found that the method captured trends in blood pressure variations correctly. The difference was within ±10 mmHgfor all of the cases. In a comparison using the Bland-Altman method for the three clinical cases, the average difference was –0.4 mmHg, –1.0 mmHg, and –1.7 mmHg and standard deviation was 4.2 mmHg, 4.8 mmHg, and 4.3 mmHg, respectively, which indicated good agreement. Introducing such wearable blood pressure sensors into daily medical practice gets detailed information on continuous blood pressure variation while examinees move freely and the resulting information is used for better quality control of adult diseases. It is also expected that wearable blood pressure sensors can be used in emergency medical cases, in intensive care, and at remote sites.

Chronic hepatitis B in patients coinfected with human immunodeficiency virus in Japan: a retrospective multicenter analysis

A nationwide survey in Japan revealed that about 6 % of human immunodeficiency virus (HIV)-positive patients are coinfected with hepatitis B virus (HBV). To further analyze the features of liver disease in HIV/HBV-coinfected patients, we analyzed 252 patients from six hospitals in the HIV/AIDS (acquired immunodeficiency syndrome) Network of Japan. The mean age was 39.5 years, and the proportion of male patients was very high (243 of 252; 96 %). The main transmission route was male homosexual contact (186 of 252; 74 %), followed by heterosexual contact. The HBV genotype was determined in 77 patients. Among them, genotype A HBV was the most frequent (58 of 77; 75 %) and was detected almost exclusively in homosexual patients. Acute hepatitis B was documented in 21 patients (8 %). Three of the 252 HIV/HBV-coinfected patients developed advanced liver disease with the complication of ascites, hepatic encephalopathy, or hepatocellular carcinoma. A comparison between patients not treated and those treated with antiretroviral drugs including anti-HBV drugs revealed that the baseline liver function was worse in treated patients. However, the serum albumin levels and platelet counts in both groups increased after treatment and were similar. Liver disease-associated death was not observed. Here, we characterize the clinical features of liver disease in HIV/HBV-coinfected patients in Japan for the first time. The findings suggest that antiretroviral therapy with anti-HBV drugs may retard the progression of a liver disease and prevent liver disease-associated death in such patients.

An asthma patient with steroid-resistant decrease in peak expiratory flow after the Great East Japan earthquake showing spontaneous recovery after 1 month

People living in Japan were affected in various ways after the Great East Japan earthquake of March 11, 2011. A 52-year-old female asthma patient not directly affected by the disaster experienced a decrease in peak expiratory flow (PEF) immediately after the earthquake. Despite increasing the inhaled and oral corticosteroid doses, her PEF did not recover. One month later, her PEF level abruptly returned to normal with minimal medications, which were previously ineffective, and the asthma-related symptoms vanished. The stabilization of her state of mind and actual social state seemed to be a part of the reason for the patient's recovery.

Chlamydophilal antigens induce foam cell formation via c-Jun NH2-terminal kinase

Chlamydophila pneumoniae is known to be associated with atherosclerosis. Recent studies have reported that components of Chlamydophila pneumoniae (chlamydophilal antigens) induce foam cell formation in macrophages. However, the mechanism of foam cell formation induced by chlamydophilal antigens has yet to be elucidated. In this paper, we first found that mitogen-activated protein kinases including extracellular signal-regulated kinase, p38 and c-Jun NH2 terminal kinase are phosphorylated after stimulation by chlamydophilal antigens. We then showed that chlamydophilal antigens induce foam cell formation mainly via c-Jun NH2 terminal kinase. Finally, we demonstrated that foam cell formation and phosphorylation of mitogen-activated protein kinases induced by chlamydophilal antigens are mainly recognized through Toll-like receptor 2. These results collectively indicated that chlamydophilal antigens induce foam cell formation mainly via Toll-like receptor 2 and c-Jun NH2 terminal kinase.

Macrophage tolerance induced by stimulation with Toll-like receptor 7/8 ligands

The engagement of Toll-like receptors (TLRs) results in resistance to subsequent challenge with respective ligands in macrophages. Studies have shown that stimulation by ligands for TLR2, TLR4, TLR5 and TLR9 induces this state of hypo-responsiveness (homo-tolerance) towards subsequent stimulation with the same ligands. However, whether homo-tolerance is induced by the ligands of TLR7/8 has not been previously determined. We found that ligands for TLR7/8, namely ss-RNA from HIV and an imidazoquinoline compound, R848, induced macrophage tolerance, as judged by the production of the chemokine MIP-1beta. IRAK-1 phosphorylation was also inhibited in the tolerant cells after subsequent stimulation with R848, although no significant differences were observed in the protein levels of TLR7 between tolerant and non-tolerant cells. These results indicate that macrophage tolerance induced by TLR7/8 ligands is regulated at least at the level of IRAK-1 activation.

Relationship between the initial dose of micafungin and its efficacy in patients with candidemia

Micafungin, the first licensed echinocandin in Japan, has shown excellent in vitro and in vivo activity against all Candida species. However, the appropriate dose for the initial treatment of candidemia remains to be determined. In this study, we retrospectively examined the relationship between the clinical outcome of candidemia and the initial dose of micafungin. Patients were divided into two groups according to the initial dose of micafungin administered: group I (<2.25 mg/kg/day) and group II (>or=2.25 mg/kg/day). Micafungin produced an excellent 30-day clinical response in patients with candidemia, including Candida parapsilosis; the overall 30-day clinical response was 86%. The administration of higher doses of micafungin accelerated the clinical response and duration until the clinical response in group II was significantly shorter than that in group I (P = 0.021). However, no significant differences were observed in the 30-day mortality attributable to the fungal infection between the two groups. Considering these results, we recommend the administration of 2.25 mg/kg/day or more of micafungin in the initial treatment of patients with candidemia.

Bacterial flagellin inhibits T cell receptor-mediated activation of T cells by inducing suppressor of cytokine signalling-1 (SOCS-1)

Flagellin, the structural component of bacterial flagella, is secreted by pathogenic and commensal bacteria, and is recognized by Toll-like receptor (TLR) 5. Flagellin is a common bacterial antigen present on most motile bacteria and is speculated to contribute to the activation of CD4+ T cells in the intestine. However, molecular mechanisms by which flagellin regulate T cell activation remains to be determined. Using Jurkat T cells or human primary T cell, we showed that flagellin stimulation induced tyrosine phosphorylation of TLR5 and activation of both mitogen-activated protein kinases and nuclear factor kappaB. In addition, stimulation by flagellin did not induce nuclear factor of activated T cells (NFAT) activation, while stimulation via the T cell receptor (TCR) leads to activation of NFAT. However, TCR-mediated NFAT activation and tyrosine phosphorylation of zeta-associated protein 70 (Zap-70) were inhibited in cells pre-stimulated by flagellin. Furthermore, flagellin stimulation induced suppressor of cytokine signalling-1 (SOCS-1), which formed a complex with Zap-70 after stimulation via TCR, and inhibition of SOCS-1 expression by SOCS-1-specific small interfering RNA reinstated TCR-mediated activation of NFAT in cells pre-stimulated with flagellin. These results collectively indicate that bacterial flagellin inhibits TCR-mediated activation of T cells by inducing SOCS-1.

Changes in the index of sweat ion concentration with increasing sweat during passive heat stress in humans

To investigate the pattern changes in the index of sweat ion concentration at skin surface with increasing sweat during passive heat stress in humans, we measured conductivity of the perfused water with sweat as the index of sweat ion concentration and sweat rate, continuously at the chest skin surface. Eight healthy subjects (22.4 +/-1.0 years) were passively heated by lower-leg immersion in a hot water bath of 42 degrees C for 50 min in an ambient temperature of 28 degrees C and relative humidity of 50%. The internal temperature (Tor) thresholds of sweat rate and index of sweat ion concentration were almost similar. Concomitant onset for the index of sweat ion concentration and sweat rate occurred but two types of linear regression lines were identified in the relationship between the index of sweat ion concentration and sweat rate at a boundary sweat rate value of 0.30 +/- 0.08 mg cm(-2) min(-1). The slope of the regression line at low levels of sweat (slope 0.02 +/- 0.01 V mg(-1) cm(-2) min(-1)) was significantly gradual compared with that at moderate levels of sweat (slope 0.30 +/- 0.08 V mg(-1) cm(-2) min(-1)) (P<0.05). These results suggest that at low levels of sweat the index of sweat ion concentration responds gradually with respect to sweat rate, which may be due to the ion reabsorption capacity of the sweat duct, and then the index of sweat ion concentration increased steeply with sweat rate.

Involvement of IRAK-M in peptidoglycan-induced tolerance in macrophages

The molecular mechanisms by which pathogen-associated molecular patterns recognized by TLR2, such as peptidoglycan (PGN), induce homotolerance are largely unknown. It was recently reported that IRAK-M negatively regulates TLR signaling. In this study, we elucidate the molecular mechanisms of tolerance induced by PGN, with a focus on the role of IRAK-M. We demonstrate that pretreatment of macrophage RAW264.7 cells with a high concentration (30 microg/ml) of PGN for 16 h effectively induces tolerance against following stimulation with 30 microg/ml of PGN; while pretreatment with a low concentration (1 microg/ml) of PGN does not. IRAK-M is induced in cells treated with the high concentration of PGN 4-24 h after PGN stimulation, but not in cells treated with the low concentration of PGN up to 24 h after stimulation. Phosphorylation of MAPKs and IkappaBalpha is inhibited after the second PGN stimulation in tolerant cells. Kinase activity of IRAK-1 and association between IRAK-1 and MyD88 are also suppressed in PGN-induced tolerant cells. Furthermore, down-regulation of IRAK-M expression by small interfering RNAs specific for IRAK-M reinstates the production of TNF-alpha after PGN restimulation. These results suggest that induction of IRAK-M and inhibition of kinase activity of IRAK-1 are crucial to PGN-induced tolerance in macrophages.

A patient with E. coli-induced pyelonephritis and sepsis who transiently exhibited symptoms associated with primary biliary cirrhosis

A 28-year-old woman had chief complaints of headache and a 40 degrees C fever. At this time, findings indicative of inflammation including elevated CRP and increased WBC were observed, and E. coli was detected on blood and urine culture. As a result, the patient was diagnosed with pyelonephritis and sepsis. Furthermore, markedly increased hepatobiliary enzymes and elevated anti-mitochondrial antibody were confirmed. The administration of antimicrobial agents resulted in improvement of the pyelonephritis and sepsis and normalization of hepatobiliary enzyme and anti-mitochondrial antibody levels. It has been documented that the incidence of urinary tract infection is high among patients with primary biliary cirrhosis (PBC). The findings obtained from the present patient are of considerable interest in elucidating the mechanism of onset in PBC.

Raf1 plays a pivotal role in lipopolysaccharide-induced activation of dendritic cells

Activation of extracellular-regulated kinases 1/2 (ERK) is involved in lipopolysaccharide (LPS)-induced cellular responses such as the increased production of proinflammatory cytokines. However, mitogen-activated protein kinases (MAPKs) such as p38 are also activated by LPS and have been postulated to be important in the control of these end points. Therefore, establishing the relative contribution of MAPKs in each cell type is important, as is elucidating the molecular mechanisms by which these MAPKs are activated in LPS-induced signaling cascades. We demonstrated in DC2.4 dendritic cells that ERK regulates tyrosine phosphorylation of phosphatidyl-inositol-3-kinase (PI3-K) and the production of TNF-alpha. We also demonstrated that Raf1 is phosphorylated and involved in the production of TNF-alpha and tyrosine phosphorylation of PI3-K via ERK. Raf1 also regulates the activation of NF-kappaB. We propose that Raf1 plays a pivotal role in LPS-induced activation of the dendritic cells.

Janus kinase 2 is involved in lipopolysaccharide-induced activation of macrophages

The mechanisms by which lipopolysaccharide (LPS) is recognized, and how such recognition leads to innate immune responses, are poorly understood. Stimulation with LPS induces the activation of a variety of proteins, including mitogen-activated protein kinases (MAPKs) and NF-kappaB. Activation of protein tyrosine kinases (PTKs) is also necessary for a number of biological responses to LPS. We used a murine macrophage-like cell line, RAW264.7, to demonstrate that Janus kinase (JAK)2 is tyrosine phosphorylated immediately after LPS stimulation. Anti-Toll-like receptor (TLR)4 neutralization antibody inhibits the phosphorylation of JAK2 and the c-Jun NH2-terminal protein kinase (JNK). Both the JAK inhibitor AG490 and the kinase-deficient JAK2 protein reduce the phosphorylation of JNK and phosphatidylinositol 3-kinase (PI3K) via LPS stimulation. Pharmacological inhibition of the kinase activity of PI3K with LY-294002 decreases the phosphorylation of JNK. Finally, we show that JAK2 is involved in the production of IL-1beta and IL-6. PI3K and JNK are also important for the production of IL-1beta. These results suggest that LPS induces tyrosine phosphorylation of JAK2 via TLR4 and that JAK2 regulates phosphorylation of JNK mainly through activation of PI3K. Phosphorylation of JAK2 via LPS stimulation is important for the production of IL-1beta via the PI3K/JNK cascade. Thus JAK2 plays a pivotal role in LPS-induced signaling in macrophages.