Peripheral Dopamine Suppression and Elevated Cystatin C in Early Diabetic Nephropathy in Spontaneously Diabetic Rats.

Intrarenal dopamine plays a protective role against the development of diabetic nephropathy during the early stages of the disease. In streptozotocin-induced diabetic mice with a renal-specific catechol-O-methyl transferase knockout, intrarenal dopamine was found to suppress glomerular hyperfiltration, reduce oxidative stress and inflammation, and inhibit fibrosis. However, while dopamine activation in streptozotocin-induced diabetic models has been shown to provide renal protection, the role of dopamine in models of naturally induced diabetes mellitus is still unclear. In the present study, we administered 10 mg/kg p.o. benserazide, a peripheral decarboxylase inhibitor, to Spontaneously Diabetic Torii rats daily, in order to investigate the activation of the renal dopaminergic system during diabetic nephropathy progression. Our findings show that peripheral dopamine decreased urinary 8-iso-prostaglandin F2a and suppressed increases in plasma cystatin C levels. This study demonstrates that a reduction in peripheral dopamine can exacerbate renal dysfunction, even in the early stages of diabetic nephropathy characterized by glomerular hyperfiltration, thereby clarifying the pivotal role of endogenous peripheral dopamine in modulating oxidative stress and kidney performance.

A method for measuring serum levels of melanin-associated indole metabolites using LC-MS/MS and its application to malignant melanoma.

BACKGROUND AND AIMS: With the development of novel therapies for advanced malignant melanoma (MM), biomarkers that can accurately reflect the progression of MM are needed. Serum levels of melanin-related indole metabolites such as 5-hydroxy-6-methoxyindole-2-carboxylic acid (5H6MI2C) and 6-hydroxy-5-methoxyindole-2-carboxylic acid (6H5MI2C) are potential biomarkers for MM. Here, we describe the development of a mass spectrometry (MS)-based assay to determine serum levels of 5H6MI2C and 6H5MI2C. MATERIALS AND METHODS: We developed a stable isotope dilution-selective reaction monitoring-MS protocol using liquid chromatography tandem mass spectrometry (LC-MS/MS) to measure human serum 5H6MI2C and 6H5MI2C levels. Analytical evaluations of the method were performed and the method was applied to serum samples from MM patients (n = 81). RESULTS: The method established in this study showed high reproducibility and linearity. This novel method also found that serum 6H5MI2C levels were significantly elevated in patients with metastatic MM compared to those with non-metastatic MM. Unfortunately, 5H6MI2C did not show a comparable significant difference. CONCLUSION: We successfully established measurement methods for serum 5H6MI2C and 6H5MI2C levels using LC-MS/MS. Serum 6H5MI2C levels offer a potential marker for MM.

Association between vascular endothelial dysfunction and stroke incidence in the general Japanese population: Results from the tohoku medical megabank community-based cohort study.

Background: Flow-mediated dilation (FMD) measures vascular endothelial function by evaluating the vasodilatory response of blood vessels to increased blood flow. Nevertheless, the association between FMD and stroke incidence in a general population remains unclear. This study investigated the association between vascular endothelial function and stroke incidence in the general Japanese population. Methods: Based on cohort data from the Tohoku Medical Megabank Community-based Cohort Study, participants aged ≥18 years were recruited from Iwate Prefecture, with the final sample comprising 2952 subjects. Results: The FMD level was 0.5%-27.1%, with a median of 5.0% (interquartile, 4.2%-11.3%). The mean follow-up period was 5.5 ± 1.8 years (range, 0.6-6.9 years). After dividing the participants into two subgroups according to the median FMD value, a multivariate Cox regression analysis adjusting for gender, age, smoking, alcohol consumption, systolic blood pressure, low-density lipoprotein cholesterol, estimated glomerular filtration rate, N-terminal pro-brain natriuretic peptide, high-sensitivity cardiac troponin T and hemoglobin A1c revealed that a lower FMD value was strongly associated with incidences of total stroke (hazard ratio[HR] = 2.13, 95% confidence interval[CI] = 1.48-3.07, p < 0.001), ischemic stroke (HR = 3.33, 95%CI = 2.00-5.52, p < 0.001), nonlacunar stroke (HR = 2.77, 95%CI = 1.49-5.16, p = 0.001), and lacunar stroke (HR = 5.12, 95%CI = 1.74-16.05, p = 0.003). Conclusions: This study showed that a low FMD value might reflect vascular endothelial dysfunction and then was associated with ischemic stroke incidence in the general Japanese population, suggesting that FMD can be used as a tool to identify future stroke risk.

Evaluation of a novel sample preparation method for identifying Aspergillus fumigatus using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry: Combining Yatalase and silica beads treatment.

Aspergillus spp. belong to filamentous fungi and sometimes cause invasive aspergillosis which has high mortality. Filamentous fungi are generally identified morphologically. However, morphologic identification is time consuming and requires advanced skills. It is difficult to train technicians and ensure a high level of quality. Therefore, an identification technique that is both accurate and relatively easy to learn is needed. In the present study, we focused on the effects of Yatalase and silica beads, which enable the efficient extraction of proteins via cell wall disruption of Aspergillus spp., and aimed to establish a novel sample preparation method using Yatalase and silica beads to enhance the efficiency of Aspergillus spp. identification with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The sample preparation method using the combination of Yatalase and silica beads showed higher accuracy for the identification of Aspergillus spp. compared with Yatalase or silica beads alone. The Yatalase/silica beads method also resulted in significantly higher identification scores compared with the conventional method for the identification of Aspergillus fumigatus (n = 33). These findings indicate that our novel Yatalase/silica beads method provides more reliable identification of A. fumigatus than does the conventional method.

Human Plasma Xanthine Oxidoreductase Activity in Cardiovascular Disease: Evidence from a Population-Based Study.

Xanthine oxidoreductase (XOR) and its products contribute to the development of chronic inflammation and oxidative stress. Excessive XOR activity is believed to promote inflammatory responses and atherosclerotic plaque formation, which are major cardiovascular risk factors. The mechanisms of XOR activity in the development and progression of cardiovascular disease (CVD), coupled with the complexity of the relationship between XOR activity and the biological effects of uric acid; reactive oxygen species; and nitric oxide, which are the major products of XOR activity, have long been debated, but have not yet been clearly elucidated. Recently, a system for measuring highly sensitive XOR activity in human plasma was established, and there has been progress in the research on the mechanisms of XOR activity. In addition, there are accumulating findings about the relationship between XOR activity and CVD. In this narrative review, we summarize existing knowledge regarding plasma XOR activity and its relationship with CVD and discuss future perspectives.

Association between Plasma Xanthine Oxidoreductase Activity and the Renal Function in a General Japanese Population: The Tohoku Medical Megabank Community-Based Cohort Study.

INTRODUCTION: Xanthine oxidoreductase (XOR) has been identified as a critical source of reactive oxygen species in various pathophysiological conditions, including hypertension, endothelial dysfunction, and atherosclerosis. This study investigated the association between XOR and renal function in a general Japanese population. METHODS: The Iwate Tohoku Medical Megabank Organization pooled individual participant data from a community-based cohort study in Iwate prefecture. Chronic kidney disease (CKD) was estimated using the estimated glomerular filtration rate of cystatin C (eGFRcys). Individuals with a history of hyperuricemia or severe renal dysfunction (eGFRcys <15 mL/min/1.73 m2 or undergoing dialysis) were excluded from the study. We performed a multinominal multivariate logistic analysis adjusted for age, blood pressure, uric acid, glycated hemoglobin A1c, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol to associate XOR activity and renal function. RESULTS: The present study included 4,248 participants (male/female: 1,373/2,875, age: 62.9 ± 11.7 years). When participants were divided according to XOR quartiles, blood pressure, body mass index, uric acid, low-density lipoprotein cholesterol, and glycated hemoglobin A1c were highest in the highest XOR quartile (all p < 0.001). The XOR activity was significantly higher in the subgroup with CKD stage G3 and G4 (G1 vs. G2 vs. G3-G4: 44.8 ± 40.5 vs. 52.0 ± 42.9 vs. 54.1 ± 43.9 pmol/h/mL, p = 0.02). The higher XOR activity was significantly associated with an increase of CKD stage: the odd ratios (95% confidence intervals) per 1 pmol/h/mL increase in XOR activity with CKD stage G1 as a reference were 1.37 (1.13-1.73) in G2 and 1.51 (1.30-1.84) in G3-G4. CONCLUSION: The present study concluded that high XOR activity was associated with the severity of CKD in a general Japanese population, suggesting that upregulated XOR activity may be involved in advanced renal dysfunction.

Clinical and electrocardiographic characteristics in patients with fulminant myocarditis.

Background: The purpose of this study was to evaluate clinical and electrocardiographic characteristics in patients with fulminant myocarditis. Methods: A total of 72 patients were divided into three groups: pericarditis (control: n = 25), acute myocarditis (n = 27), and fulminant myocarditis (n = 20). Patients' characteristics and electrocardiograms on admission were retrospectively analyzed in the three groups. Results: BNP levels in the fulminant group were significantly higher than those in the other two groups. ST elevation was observed at lead aVR in the fulminant myocarditis group, whereas ST depression was observed at lead aVR in the other groups (p = .001). The maximum degree of ST elevation among the three groups was similar. However, the number of ST-elevation leads in the fulminant myocarditis group was significantly lower than that in the other groups (p = .004). The voltage of R wave in lead V5 in the fulminant myocarditis group was significantly lower than that in the other groups (p = .005). Moreover, in the Cabrera sequence, the prevalence of ST elevation in the inferior leads, aVR, and V3-V6 in the fulminant myocarditis group was significantly or nearly significantly lower than that in the other groups. Conclusions: In fulminant myocarditis, ST-segment elevation was observed in lead aVR, and contrarily, the number and extent of ST-segment elevation and R wave voltage were smaller than those in the other groups. These results suggest that the number of myocytes with maintained action potential may be reduced following progressive myocardial damage and interstitial edema due to severe inflammation.

Vitamin D Metabolite Ratio in Pregnant Women with Low Blood Vitamin D Concentrations Is Associated with Neonatal Anthropometric Data.

Existing evidence on the correlation between maternal vitamin D concentrations and birth outcomes is conflicting. Investigation of these associations requires accurate assessment of vitamin D status, especially in individuals with low 25-hydroxyvitamin D (25(OH)D) concentrations. This study examined the correlations between birth outcomes and the maternal vitamin D metabolite ratio (VMR) 1 (defined as the ratio of 24,25(OH)2D3 to 25(OH)D) and VMR2 (defined as the ratio of 3-epi-25(OH)D3 to 25(OH)D) using data from the Japan Environment and Children's Study at Chiba Regional Center. A total of 297 mother-neonate pairs were analyzed. Using liquid chromatography-tandem mass spectrometry, we measured 25(OH)D2, 25(OH)D3, 24,25(OH)2D3, and 3-epi-25(OH)D3 concentrations in maternal serum samples. These data were analyzed in relation to birth anthropometric data using multivariable linear regression. Of the study participants, 85.2% showed insufficient vitamin D concentrations. VMR1 was strongly correlated with 25(OH)D concentrations, whereas VMR2 showed a weak correlation. Only VMR2 was associated with all anthropometric data. VMR2 in pregnant women with low vitamin D blood concentrations is a useful marker for neonatal anthropometric data and is independent of 25(OH)D. Accurate measurement of vitamin D metabolites could help better understand the effects of vitamin D on birth outcomes.

Association between total type I collagen N-terminal propeptide and coronary artery disease risk score in the general Japanese population.

Background: Bone metabolic dysregulation plays an important role in the pathogenesis of atherosclerosis; however, whether its markers contribute to coronary artery disease (CAD) risk in the general population remains unclear. Therefore, this study aimed to analyze the association between bone metabolic markers and CAD risk score in the general Japanese population. Methods: The Iwate Medical Megabank Organization collected individual participant data during a community-based cohort study in the Iwate prefecture (n = 5,095, age = 58.9 ± 12.4 years). Participants with osteoporosis, chronic kidney disease, malignant disease, or primary wasting disease were excluded from the study. The present study measured the levels of circulating bone metabolic markers, including total type I collagen N-terminal propeptide (TP1NP), bone-type alkaline phosphatase, cross-linked N-telopeptide of type 1 collagen (NTX), and intact parathyroid hormone. CAD risk and atherosclerosis were evaluated using the Suita score and brachial-ankle pulse wave velocity (baPWV) measurement, respectively. Results: Among the bone metabolic markers, TP1NP was strongly associated with a high Suita score (≥56 points) (OR = 0.77, 95% CI = 0.69-0.82, P < 0.001). When participants were divided into quartiles of TP1NP levels, the subgroup with the lowest TP1NP level was associated with a high Suita score (≥56 points) and high baPWV (>1,400 cm/s). Conclusions: This study demonstrated that TP1NP levels decreased in participants with high Suita scores and high baPWV, suggesting that TP1NP downregulation may indicate future CAD risk and atherosclerosis progression in the general Japanese population.

Association between Social Isolation and Total Mortality after the Great East Japan Earthquake in Iwate Prefecture: Findings from the TMM CommCohort Study.

This study aimed to investigate whether social isolation is associated with mortality, together with the effect of the Great East Japan Earthquake on mortality, due to the social isolation of community residents living in the affected areas, using data from the Tohoku Medical Megabank Project Community-Based Cohort Study. A total of 22,933 participants (8059 men and 14,874 women), who were free from cancer and cardiovascular disease, were followed up with death as an endpoint for five years. Social isolation was assessed using the Lubben Social Network Scale (cut-off, 11/12). Using Cox proportional hazards models, hazard ratios (HRs) of total mortality and 95% confidence intervals (CIs) associated with social isolation (no isolation as the reference) were estimated. The latter was significantly associated with an increased risk of total mortality (1.38 (1.04-1.83) in men and 1.49 (1.02-2.19) in women). Moreover, among those with social isolation, the risk of mortality was significantly higher, especially for women with house damage and men who had experienced a death in the family. The disaster may have raised the risk of mortality due to social isolation.

Association between high-sensitivity cardiac troponin T levels and incident stroke in the elderly Japanese population: Results from the Tohoku Medical Megabank Community-based Cohort Study.

Elevated levels of circulating high-sensitivity cardiac troponin T (hs-cTnT) are associated with cardiovascular disease. This study aimed to examine whether hs-cTnT levels are associated with incident stroke in the elderly population. The Iwate Tohoku Medical Megabank Organization pooled participant data for a community-based cohort study (n = 15,063, 69.6 ± 3.4 years), with a mean follow-up period of 5.23 years for all-cause death and incident stroke. The follow-up revealed 316 incident strokes, including atherothrombotic (n = 98), cardioembolic (n = 54), lacunar (n = 63), hemorrhagic (n = 101), and 178 all-cause deaths. Participants were classified into quartiles according to hs-cTnT levels (Q1 ≦ 4 ng/L, Q2: 5-6 ng/L, Q3: 7-9 ng/L, and Q4 > 9 ng/L). After adjusting for sex, age, smoking, drinking, systolic blood pressure, estimated glomerular filtration rate, N-terminal pro-brain natriuretic peptide, hemoglobin A1c, and lipid profile, a Cox proportional hazard model showed that higher hs-cTnT levels were associated with ischemic stroke (Q1 vs. Q4, hazard ratio [HR] = 2.24, 95 % confidence interval [CI] = 1.12-4.51, p = 0.023). The incident of total stroke was not associated with hs-cTnT levels (Q1 vs. Q4, HR 1.39, 95 % CI = 0.89-1.74, p = 0.145). Numerical differences were highest regarding incident lacunar stroke subtypes; however, this association was not statistically significant. Higher hs-cTnT concentrations were associated with ischemic stroke in the elderly Japanese population.

Development of a sensitive liquid chromatography-tandem mass spectrometry method for quantification of human plasma arginine vasopressin.

BACKGROUND AND AIMS: Direct measurement of arginine vasopressin (AVP) via immunoassays is not widely conducted, mainly because of technical constraints. Liquid chromatography-tandem mass spectrometry (LC/MS/MS) has been widely used as the gold standard in clinical chemistry. Here, we aimed to develop an MS-based assay to determine human plasma AVP and compare the results with those obtained using a conventional immunoassay. MATERIALS AND METHODS: We developed a protocol using triple quadrupole MS coupled with LC for the measurement of human plasma AVP. Analytical evaluations of the method were performed, and the results obtained using LC/MS/MS and radioimmunoassay (RIA) were compared. RESULTS: The lower limit of quantification (LLOQ) for plasma AVP obtained using LC/MS/MS and RIA were 0.2 and 0.4 pg/mL, respectively. Although there was a weak overall correlation between the results obtained using the two different methods, the RIA results did not agree with the LC/MS/MS results, particularly at low concentrations. CONCLUSIONS: AVP detection through RIA is not satisfactory compared with that using LC/MS/MS. Diagnostic values of direct AVP measurements must be evaluated based on the results obtained via sensitive and accurate MS-based methods rather than those obtained through RIA.

Complement factor B regulates cellular senescence and is associated with poor prognosis in pancreatic cancer.

BACKGROUND: The interplay between cancer cells and stromal components, including soluble mediators released from cancer cells, contributes to the progression of pancreatic ductal adenocarcinoma (PDAC). Here, we set out to identify key secreted proteins involved in PDAC progression. METHODS: We performed secretome analyses of culture media of mouse pancreatic intraepithelial neoplasia (PanIN) and PDAC cells using Stable Isotope Labeling by Amino acid in Cell culture (SILAC) with click chemistry and liquid chromatography-mass spectrometry (LC-MS/MS). The results obtained were verified in primary PDAC tissue samples and cell line models. RESULTS: Complement factor B (CFB) was identified as one of the robustly upregulated proteins, and found to exhibit elevated expression in PDAC cells compared to PanIN cells. Endogenous CFB knockdown by a specific siRNA dramatically decreased the proliferation of PDAC cells, PANC-1 and MIA PaCa-II. CFB knockdown induced increases in the number of senescence-associated-ß-galactosidase (SA-ß-gal) positive cells exhibiting p21 expression upregulation, which promotes cellular senescence with cyclinD1 accumulation. Furthermore, CFB knockdown facilitated downregulation of proliferating cell nuclear antigen and led to cell cycle arrest in the G1 phase in PDAC cells. Using immunohistochemistry, we found that high stromal CFB expression was associated with unfavorable clinical outcomes with hematogenous dissemination after surgery in human PDAC patients. Despite the presence of enriched CD8+ tumor infiltrating lymphocytes in the PDAC tumor microenvironments, patients with a high stromal CFB expression exhibited a significantly poorer prognosis compared to those with a low stromal CFB expression. Immunofluorescence staining revealed a correlation between stromal CFB expression in the tumor microenvironment and an enrichment of immunosuppressive regulatory T-cells (Tregs), myeloid-derived suppressor cells (MDSCs) and tumor-associated macrophages (TAMs). We also found that high stromal CFB expression showed a positive correlation with high CD8+/Foxp3+ Tregs populations in PDAC tissues. CONCLUSIONS: Our data indicate that CFB, a key secreted protein, promotes proliferation by preventing cellular senescence and is associated with immunological tumor promotion in PDAC. These findings suggest that CFB may be a potential target for the treatment of PDAC.

Association between the social isolation and depressive symptoms after the great East Japan earthquake: findings from the baseline survey of the TMM CommCohort study.

BACKGROUND: Social isolation and mental health issues have become a severe problem in disaster areas in the Great East Japan Earthquake. This study examined whether the combination of the house damage and social isolation or the combination of the death of family members and social isolation is associated with depressive symptoms among survivors using the baseline study data of the Tohoku Medical Megabank Project Community-Based Cohort Study (TMM CommCohort Study). METHODS: We used cross-sectional data from a baseline survey of 48,958 participants (18,423 males, 30,535 females; aged 60.1 ± 11.2 years) to examine the association between social isolation measured by the Lubben social network scale 6 (LSNS-6) and depressive symptoms measured by the Center for Epidemiological Studies-Depressive Scale (CES-D). The presence of social isolation and depressive symptoms was defined by an LSNS-6 score of < 12 and a CES-D score of ≥16, respectively. We performed a logistic regression analysis to determine the multivariable-adjusted odds ratio (95% confidence interval) [AOR (95% CI)] for depressive symptoms according to sex in the social isolation in comparison to without social isolation, and the associations of the combination of the house damage or the death of family members and social isolation and depressive symptoms. RESULTS: Social isolation was significantly associated with depressive symptoms (males: OR = 1.87; 95% CI = 1.72-2.04, females: OR = 2.13; 95% CI = 2.00-2.26). Both males and females respondents with severe house damage and social isolation had a greater risk of depressive symptoms in comparison to those with an undamaged house and without social isolation (males: OR = 3.40; 95% CI = 2.73-4.24, females: OR = 2.92; 95% CI = 2.46-3.46). The risk of depressive symptoms was also higher in both males and females respondents with the death of family members and social isolation in comparison to those without the death of family members and without social isolation (males: OR = 2.18; 95% CI = 1.90-2.50, females: OR = 2.60; 95% CI = 2.35-2.88). CONCLUSION: The findings suggested that a combination of social isolation and severe house damage and the death of family members caused by a large-scale natural disaster was associated with a higher risk of depressive symptoms although the interaction was not statistically significant.

Effect of humidity during sample preparation on bacterial identification using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is a highly reliable and efficient technology for the identification of microbial pathogens. We previously found that 40% humidity was the optimal condition for the preparation of samples (co-crystallization of the sample and matrix) for serum peptidomic analysis via MALDI-TOF MS profiling. This optimum temperature was applied to obtain the highest reproducibility and throughput and greatest number of peaks. We therefore hypothesized that humidity control was also essential for MALDI-TOF MS bacterial identification. In this study, we constructed a simple sample preparation device that enables humidity control and used it for co-crystallization of the sample and matrix. Identification scores for five Gram-negative bacteria and six Gram-positive bacteria were determined using the MALDI BioTyper® system at three humidity ranges (10-20%, 30-40%, and 50-60%). As a result, higher identification scores were obtained at 30-40% humidity than at 10-20% or 50-60% humidity. At 30-40% humidity, 517/550 (94.0%) isolates scored greater than 2.0, indicating the success of species-level identification. Similarly, 537/550 (97.6%) isolates scored greater than 1.7, indicating the success of genus-level identification. Thus, 30-40% humidity generated optimal MALDI-TOF MS identification scores and the highest percentage of correct identifications. These results could lead to further improvements in the accuracy of MALDI-TOF MS bacterial identification.

Plasma Xanthine Oxidoreductase Activity Is Associated with a High Risk of Cardiovascular Disease in a General Japanese Population.

The purpose of this study was to investigate the association between xanthine oxidoreductase (XOR) activity and a high risk of cardiovascular disease (CVD) in a general Japanese population. The Iwate Tohoku Medical Megabank Organization pooled individual participant data from a general population-based cohort study in Iwate prefecture. The cardiovascular risk was calculated using the Framingham Risk Score (FRS). A total of 1605 of the 1631 participants (98.4%) had detectable XOR activity. Multiple regression analysis demonstrated that XOR activity was independently associated with body mass index (ß = 0.26, p < 0.001), diabetes (ß = 0.09, p < 0.001), dyslipidemia (ß = 0.08, p = 0.001), and uric acid (ß = 0.13, p < 0.001). Multivariate analysis showed that the highest quartile of XOR activity was associated with a high risk for CVD (FRS ≥ 15) after adjustment for baseline characteristics (OR 2.93, 95% CI 1.16-7.40). The area under the receiver operating characteristic curves of the FRS with XOR activity was 0.81 (p = 0.008). XOR activity is associated with a high risk for CVD, suggesting that high XOR activity may indicate cardiovascular risk in a general Japanese population.

Study Profile of the Tohoku Medical Megabank Community-Based Cohort Study.

BACKGROUND: We established a community-based cohort study to assess the long-term impact of the Great East Japan Earthquake on disaster victims and gene-environment interactions on the incidence of major diseases, such as cancer and cardiovascular diseases. METHODS: We asked participants to join our cohort in the health check-up settings and assessment center based settings. Inclusion criteria were aged 20 years or over and living in Miyagi or Iwate Prefecture. We obtained information on lifestyle, effect of disaster, blood, and urine information (Type 1 survey), and some detailed measurements (Type 2 survey), such as carotid echography and calcaneal ultrasound bone mineral density. All participants agreed to measure genome information and to distribute their information widely. RESULTS: As a result, 87,865 gave their informed consent to join our study. Participation rate at health check-up site was about 70%. The participants in the Type 1 survey were more likely to have psychological distress than those in the Type 2 survey, and women were more likely to have psychological distress than men. Additionally, coastal residents were more likely to have higher degrees of psychological distress than inland residents, regardless of sex. CONCLUSION: This cohort comprised a large sample size and it contains information on the natural disaster, genome information, and metabolome information. This cohort also had several detailed measurements. Using this cohort enabled us to clarify the long-term effect of the disaster and also to establish personalized prevention based on genome, metabolome, and other omics information.

A genome-wide association study for highly sensitive cardiac troponin T levels identified a novel genetic variation near a RBAK-ZNF890P locus in the Japanese general population.

BACKGROUND: Cardiovascular disease (CVD) is a major cause of mortality worldwide. High-sensitivity cardiac troponin T (hs-cTnT) is released into the bloodstream due to cardiomyocyte damage and is associated with a high CVD risk. This study aimed to investigate hs-cTnT-related genetic variation and to examine whether this is an associated risk factor for CVD in the Japanese general population. METHODS: This was a genome-wide association study (GWAS) based on a cohort from the 2013 Tohoku Medical Megabank Project community study. The GWAS was performed using a HumanOmniExpressExome BeadChip array with 914,035 autosomal single-nucleotide polymorphisms. The Framingham Risk Score and the Suita score were used to evaluate the future risk of CVD. RESULTS: The GWAS identified 10 loci reaching suggestive significance in the discovery cohort. A replication analysis confirmed that one of the 10 loci, rs7798496, is associated with elevated hs-cTnT levels. The combined P value in the discovery and replication cohorts for the association between the rs7798496 and hs-cTnT levels was 3.4 × 10-8, which indicates that the novel variant reached genome-wide significance. The rs7798496 loci was located at an intergenic region between the retinoblastoma gene product (RB)-associated Krüppell-associated box (KRAB) zinc finger, zinc finger protein 890, and pseudogene (ZNF890P). Logistic regression analysis revealed that the presence of the rs7798496 T allele was strongly associated with a high risk for CVD. CONCLUSIONS: This study provides insights into a link between a novel genetic variant, T allele of rs7798269, and elevated hs-cTnT levels as a future risk for CVD in the general Japanese population.

Derivatization-based quadruplex LC/ESI-MS/MS method for high throughput quantification of serum dehydroepiandrosterone sulfate.

The quantification of the circulating dehydroepiandrosterone sulfate (DHEAS) might be of diagnostic help for several diseases. For the DHEAS quantification, LC/ESI-MS/MS has the advantage of a high specificity compared with immunoassay, whereas LC/ESI-MS/MS has room to improve the analysis throughput. One of the promising solutions to enhance the analysis throughput is sample-multiplexing in the same injection, which can reduce the total LC/ESI-MS/MS run time. In this study, a quadruplex LC/ESI-MS/MS method was developed to quantify DHEAS in four different serum samples in a single run. After the four samples were separately deproteinized and derivatized with one of four Girard reagents (Girard reagent T, P and their isotopologs), the resulting samples were mixed, then injected into the LC/ESI-MS/MS. The applicability and advantage of the developed method were evaluated based on the analysis of nine batches of serum samples from healthy subjects (total 36 samples). The limit of quantitation was 0.050 µg/ml, which was sensitive enough for clinical laboratory use. The method was precise (intra- and inter-assay RSDs ≤ 3.6%), accurate (94.4-108.1%) and robust for the matrix effects. The analysis time was also shortened by about 60% for 36 samples by the introduced method compared with the conventional method.

Mass spectrometry-based microbiological testing for blood stream infection.

BACKGROUND: The most successful application of mass spectrometry (MS) in laboratory medicine is identification (ID) of microorganisms using matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) in blood stream infection. We describe MALDI-TOF MS-based bacterial ID with particular emphasis on the methods so far developed to directly identify microorganisms from positive blood culture bottles with MALDI-TOF MS including our own protocols. We touch upon the increasing roles of Liquid chromatography (LC) coupled with tandem mass spectrometry (MS/MS) as well. MAIN BODY: Because blood culture bottles contain a variety of nonbacterial proteins that may interfere with analysis and interpretation, appropriate pretreatments are prerequisites for successful ID. Pretreatments include purification of bacterial pellets and short-term subcultures to form microcolonies prior to MALDI-TOF MS analysis. Three commercial protocols are currently available: the Sepsityper® kit (Bruker Daltonics), the Vitek MS blood culture kit (bioMerieux, Inc.), and the rapid BACpro® II kit (Nittobo Medical Co., Tokyo). Because these commercially available kits are costly and bacterial ID rates using these kits are not satisfactory, particularly for Gram-positive bacteria, various home-brew protocols have been developed: 1. Stepwise differential sedimentation of blood cells and microorganisms, 2. Combination of centrifugation and lysis procedures, 3. Lysis-vacuum filtration, and 4. Centrifugation and membrane filtration technique (CMFT). We prospectively evaluated the performance of this CMFT protocol compared with that of Sepsityper® using 170 monomicrobial positive blood cultures. Although preliminary, the performance of the CMFT was significantly better than that of Sepsityper®, particularly for Gram-positive isolates. MALDI-TOF MS-based testing of polymicrobial blood specimens, however, is still challenging. Also, its contribution to assessment of susceptibility and resistance to antibiotics is still limited. For this purpose, liquid chromatography (LC) coupled with tandem mass spectrometry (MS/MS) should be more useful because this approach can identify as many as several thousand peptide sequences. CONCLUSION: MALDI-TOF MS is now an essential tool for rapid bacterial ID of pathogens that cause blood stream infection. For the purpose of assessment of susceptibility and resistance to antibiotics of the pathogens, the roles of liquid chromatography (LC) coupled with tandem mass spectrometry (MS/MS) will increase in the future.