Dioxygen Activation by Gold(I)-Distorted Porphyrin Dinuclear Complexes.

Interactions between gold-based materials and dioxygen (O2) have motivated researchers to understand reaction mechanisms for O2 activation by homo- and heterogeneous gold catalysts. In this work, gold(I) porphyrin dinuclear complexes were synthesized with a saddle-distorted porphyrin ligand. The gold(I) porphyrin complexes showed unprecedented O2 activation in the presence of protic solvents to form gold(III) tetradentate porphyrin complexes. Mechanistic insights into the O2 activation by the gold(I) center were elucidated by spectroscopic measurements and theoretical calculations, revealing that dissociation of halides on the gold(I) center by alcohol solvents and hydrogen bonding of an N-H proton in the distorted porphyrin with dioxygen played important roles in establishing the unique reactivities of gold(I) complexes.

Isomer-Selective Conversion of Au Clusters by Au(I) Thiolate Insertion.

Isomer-selective conversion is a challenging goal in the rational design of Au clusters. Herein, we demonstrate the isomer-selective conversion of Au18(ScC6)14 (ScC6 = cyclohexanethiolate) into Au24(SR)x(ScC6)20-x in high yields by reactions with gold(I) thiolate (AuSR) complexes. Electrospray ionization mass spectrometry indicated that even numbers of AuSR units are inserted into Au18(SR)x(ScC6)14-x to generate Au24(SR)x(ScC6)20-x through intermediates Au20(SR)x(ScC6)16-x or Au22(SR)x(ScC6)18-x. These results suggest that the number of constituent atoms in surface Au(I)SR oligomers only increases, while the number of electrons in an Au core is maintained. UV-vis analysis revealed the generation of one of two Au24(SR)x(ScC6)20-x isomers in the reactions of Au18(ScC6)14 with AuSR complexes, in contrast to the formation of both isomers by reactions with thiols. When the structures of Au18(SR)14 are compared with those of the Au24(SR)20 isomers, the partial structure in the Au cores is preserved in the isomer-selective conversion with AuSR complexes, regardless of the structures of the thiolate moiety.

Control over Ligand-Exchange Positions of Thiolate-Protected Gold Nanoclusters Using Steric Repulsion of Protecting Ligands.

Organic ligands on gold nanoclusters play important roles in regulating the structures of gold cores. However, the impact of the number and positions of the protecting ligands on gold-core structures remains unclear. We isolated thiolate-protected Au25 cluster anions, [Au25(SC2Ph)17(Por)1]- and [Au25(SC2Ph)16(Por)2]- (SC2Ph = 2-phenylethanethiolate), obtained by ligand exchange of [Au25(SC2Ph)18]- with one or two porphyrinthiolate (Por) ligands as mixtures of regioisomers. The ratio of two regioisomers in [Au25(SC2Ph)17(Por)1]- as measured by 1H NMR spectroscopy revealed that the selectivity could be controlled by the steric hindrance of the incoming thiols. Extended X-ray absorption fine structure studies of a series of porphyrin-coordinated gold nanoclusters clarified that the Au13 icosahedral core in the Au25 cluster was distorted through steric repulsion between porphyrin thiolates and phenylethanethiolates. This paper reveals interesting insights into the importance of the steric structures of protecting ligands for control over core structures in gold nanoclusters.

A Mechanistic Dichotomy in Two-Electron Reduction of Dioxygen Catalyzed by N,N'-Dimethylated Porphyrin Isomers.

Selective two-electron reduction of dioxygen (O2 ) to hydrogen peroxide (H2 O2 ) has been achieved by two saddle-distorted N,N'-dimethylated porphyrin isomers, an N21,N'22-dimethylated porphyrin (anti-Me2 P) and an N21,N'23-dimethylated porphyrin (syn-Me2 P) as catalysts and ferrocene derivatives as electron donors in the presence of protic acids in acetonitrile. The higher catalytic performance in an oxygen reduction reaction (ORR) was achieved by anti-Me2 P with higher turnover number (TON=250 for 30 min) than that by syn-Me2 P (TON=218 for 60 min). The reactive intermediates in the catalytic ORR were confirmed to be the corresponding isophlorins (anti-Me2 Iph or syn-Me2 Iph) by spectroscopic measurements. The rate-determining step in the catalytic ORRs was concluded to be proton-coupled electron-transfer reduction of O2 with isophlorins based on kinetic analysis. The ORR rate by anti-Me2 Iph was accelerated by external protons, judging from the dependence of the observed initial rates on acid concentrations. In contrast, no acceleration of the ORR rate with syn-Me2 Iph by external protons was observed. The different mechanisms in the O2 reduction by the two isomers should be derived from that of the arrangement of hydrogen bonding of a O2 with inner NH protons of the isophlorins.

Estimating local need for mental healthcare to inform fair resource allocation in the NHS in England: cross-sectional analysis of national administrative data linked at person level.

BACKGROUND: Equitable access to mental healthcare is a priority for many countries. The National Health Service in England uses a weighted capitation formula to ensure that the geographical distribution of resources reflects need. AIMS: To produce a revised formula for estimating local need for secondary mental health, learning disability (intellectual disability) and psychological therapies services for adults in England. METHOD: We used demographic records for 43 751 535 adults registered with a primary care practitioner in England linked with service use, ethnicity, physical health diagnoses and type of household, from multiple data-sets. Using linear regression, we estimated the individual cost of care in 2015 as a function of individual- and area-level need and supply variables in 2013 and 2014. We sterilised the effects of the supply variables to obtain individual-need estimates. We aggregated these by general practitioner practice, age and gender to derive weights for the national capitation formula. RESULTS: Higher costs were associated with: being 30-50 years old, compared with 20-24; being Irish, Black African, Black Caribbean or of mixed ethnicity, compared with White British; having been admitted for specific physical health conditions, including drug poisoning; living alone, in a care home or in a communal environment; and living in areas with a higher percentage of out-of-work benefit recipients and higher prevalence of severe mental illness. Longer distance from a provider was associated with lower cost. CONCLUSIONS: The resulting needs weights were higher in more deprived areas and informed the distribution of some 12% (£9 bn in 2019/20) of the health budget allocated to local organisations for 2019/20 to 2023/24.

Visualization by P-flow: gradient- and feature-based optical flow and vector fields extracted from image analysis.

We proposed a method for extracting the optical flow suitable for visualization, pseudo-flow (P-flow), from a natural movie [Exp. Brain Res.237, 3321 (2019)EXBRAP0014-481910.1007/s00221-019-05674-0]. The P-flow algorithm comprises two stages: (1) extraction of a local motion vector field from two successive frames and (2) tracking of vectors between two successive frame pairs. In this study, we show that while P-flow takes a feature (vector) tracking approach, it is also classified as a gradient-based approach that satisfies the brightness constancy constraint. We also incorporate interpolation and a corner detector to address the shortcomings associated with the two approaches.

Clinical feasibility of resting full-cycle ratio as a unique non-hyperemic index of invasive functional lesion assessment.

The resting full-cycle ratio (RFR) is a new physiologic index to assess myocardial ischemia. RFR and fractional flow reserve (FFR), the conventionally used index, have not been directly compared in evaluating the entire cardiac cycle. Accordingly, we aimed to compare the diagnostic performance of RFR directly with FFR and clarify the clinical feasibility of RFR as a unique non-hyperemic index in evaluating the cardiac cycle. The diagnostic performance of RFR was compared with FFR using an automated online calculation software. A total of 156 consecutive patients with 220 intermediate lesions were enrolled. RFR showed significant correlation with FFR (r = 0.774, p < 0.001). RFR systole and RFR diastole did also with FFR (r = 0.918, p < 0.001, and r = 0.733, p < 0.001, respectively). With FFR < 0.80 as a reference standard, RFR showed good diagnostic accuracy (DA: 80.5%), similar DA between RFR systole and RFR diastole (79.6% and 87.5%, p = 0.58, respectively), and good DA in any lesion locations, especially in non-left anterior descending coronary artery (LAD) lesions (73.7% and 87.6% for LAD vs. non-LAD, p < 0.05, respectively). RFR is a feasible and reliable non-hyperemic index regardless of the difference in cardiac cycle in evaluating physiological lesion severity in daily practice.

Earliest pulmonary vein potential-guided cryoballoon ablation for atrial fibrillation.

No studies have evaluated both the time-to-isolation (TTI) and the sequence of pulmonary vein (PV) potentials in cryoballoon ablation (CBA) for atrial fibrillation (AF). This study aimed to prospectively evaluate the acute results of pulmonary vein isolation (PVI) using a novel CBA technique-the earliest potential (EP) of PV-guided CBA-in paroxysmal AF. We pressed a balloon against the earliest PV potential site during PVI when TTI could not be achieved within 60 s (EP-guided CBA group). We compared 32 patients consecutively treated by EP-guided CBA to 32 patients treated without pressing the balloon against the EP site (conventional CBA group). The cryoapplication protocol was the same, except with regard to the pressing of the balloon. All 256 PVs (EP-guided CBA group, 128 PVs; conventional CBA group, 128 PVs) were isolated successfully. The TTI observation rate was similar in both groups. Compared with conventional CBA, EP-guided CBA was associated with a lower non-success rate of TTI ≤ 90 s (9% vs. 26%; P = 0.040) and shorter left atrial dwell time (38 ± 9 vs. 46 ± 19 min; P = 0.036), total procedure time (76 ± 15 vs. 87 ± 23 min; P = 0.043), and fluoroscopy time (23 ± 8 vs. 30 ± 11 min; P = 0.006). This novel EP-guided CBA approach may help facilitate the ablation procedure.

Dioxygen/Hydrogen Peroxide Interconversion Using Redox Couples of Saddle-Distorted Porphyrins and Isophlorins.

Interconversion between dioxygen (O2) and hydrogen peroxide (H2O2) has attracted much interest because of the growing importance of H2O2 as an energy source. There are many reports on O2 conversions to H2O2; however, no example has been reported on O2/H2O2 interconversion. Herein, we describe successful achievement of a reversible O2/H2O2 conversion based on an N21, N23-dimethylated saddle-distorted porphyrin and the corresponding two-electron-reduced porphyrin (isophlorin) for the first time. The isophlorin could react with O2 to afford the corresponding porphyrin and H2O2; conversely, the porphyrin also reacted with excess H2O2 to reproduce the corresponding isophlorin and O2. The isophlorin-O2/porphyrin-H2O2 interconversion was repeatedly proceeded by alternate bubbling of Ar or O2, although no reversible conversion was observed in the case of an N21, N22-dimethylated porphyrin as a structural isomer. Such a drastic change of the reversibility was derived from the directions of inner N H protons in hydrogen-bond formation of the isophlorin core with O2 as well as those of the lone pairs of the inner nitrogen atoms of the porphyrin core to form hydrogen bonds with H2O2. The intriguing isophlorin-O2/porphyrin-H2O2 interconversion was accomplished by introducing methyl groups at the inner nitrogen atoms to minimize the difference of the Gibbs free energy between isophlorin-O2/porphyrin-H2O2 states and the Gibbs activation energy of the interconversion. On the basis of the kinetic and thermodynamic analysis on the isophlorin-O2/porphyrin-H2O2 interconversion using 1H NMR and UV-vis spectroscopies and DFT calculations, we propose the formation of a two-point hydrogen-bonding adduct between the N21, N23-dimethylated porphyrin and H2O2 as an intermediate.

Vection induced by low-level motion extracted from complex animation films.

This study examined the contributions of low-, mid- and high-level visual motion information to vection. We compared the vection experiences induced by hand-drawn and computer-generated animation clips to those induced by versions of these movies that contained only their pure optic flow. While the original movies were found to induce longer and stronger vection experiences than the pure optic flow, vection onsets were not significantly altered by removing the mid- and high-level information. We conclude that low-level visual motion information appears to be important for vection induction, whereas mid- and higher-level display information appears to be important for sustaining and strengthening this vection after its initial induction.

Thioredoxin-1 maintains mechanistic target of rapamycin (mTOR) function during oxidative stress in cardiomyocytes.

Thioredoxin 1 (Trx1) is a 12-kDa oxidoreductase that catalyzes thiol-disulfide exchange reactions to reduce proteins with disulfide bonds. As such, Trx1 helps protect the heart against stresses, such as ischemia and pressure overload. Mechanistic target of rapamycin (mTOR) is a serine/threonine kinase that regulates cell growth, metabolism, and survival. We have shown previously that mTOR activity is increased in response to myocardial ischemia-reperfusion injury. However, whether Trx1 interacts with mTOR to preserve heart function remains unknown. Using a substrate-trapping mutant of Trx1 (Trx1C35S), we show here that mTOR is a direct interacting partner of Trx1 in the heart. In response to H2O2 treatment in cardiomyocytes, mTOR exhibited a high molecular weight shift in non-reducing SDS-PAGE in a 2-mercaptoethanol-sensitive manner, suggesting that mTOR is oxidized and forms disulfide bonds with itself or other proteins. The mTOR oxidation was accompanied by reduced phosphorylation of endogenous substrates, such as S6 kinase (S6K) and 4E-binding protein 1 (4E-BP1) in cardiomyocytes. Immune complex kinase assays disclosed that H2O2 treatment diminished mTOR kinase activity, indicating that mTOR is inhibited by oxidation. Of note, Trx1 overexpression attenuated both H2O2-mediated mTOR oxidation and inhibition, whereas Trx1 knockdown increased mTOR oxidation and inhibition. Moreover, Trx1 normalized H2O2-induced down-regulation of metabolic genes and stimulation of cell death, and an mTOR inhibitor abolished Trx1-mediated rescue of gene expression. H2O2-induced oxidation and inhibition of mTOR were attenuated when Cys-1483 of mTOR was mutated to phenylalanine. These results suggest that Trx1 protects cardiomyocytes against stress by reducing mTOR at Cys-1483, thereby preserving the activity of mTOR and inhibiting cell death.

Phylogeny and Immunoreactivity of Norovirus GII.P16-GII.2, Japan, 2016-17.

During the 2016-17 winter season in Japan, human norovirus GII.P16-GII.2 strains (2016 strains) caused large outbreaks of acute gastroenteritis. Phylogenetic analyses suggested that the 2016 strains derived from the GII.2 strains detected during 2010-12. Immunochromatography between 2016 strains and the pre-2016 GII.2 strains showed similar reactivity.

Formation and Isolation of a Four-Electron-Reduced Porphyrin Derivative by Reduction of a Stable 20π Isophlorin.

The two-electron reduction of a diprotonated dodecaphenylporphyrin derivative by Na2 S2 O4 gave a corresponding isophlorin (Iph) selectively. Formation of Iph was confirmed by spectroscopic measurements and the isolation of tetramethylated Iph. Further reduction of Iph proceeded to form an unprecedented four-electron-reduced porphyrin (IphH2 ), which was fully characterized by spectroscopic and X-ray crystallographic analysis. IphH2 , with a unique conformation, could be oxidized to reproduce the starting porphyrin, resulting in a proton-coupled four-electron reversible redox system.

Thermodynamics and Photodynamics of a Monoprotonated Porphyrin Directly Stabilized by Hydrogen Bonding with Polar Protic Solvents.

Addition of 1 equiv of TFA to an acetone solution containing dodecaphenylporphyrin (H2 DPP) in the presence of 10 % MeOH (v/v) resulted in selective formation of a monoprotonated form (H3 DPP+ ), in sharp contrast to protonation of H2 DPP directly affording a diprotonated form (H4 DPP2+ ) in acetone in the absence of MeOH. The crucial role of MeOH for selective H3 DPP+ formation was interpreted as hydrogen-bonding stabilization of H3 DPP+ , since a MeOH molecule was found to form hydrogen bonds with an NH proton of H3 DPP+ in the crystal. The selectivity of H3 DPP+ formation was evaluated by the formation yield of H3 DPP+ , which increased when elevating the portion of MeOH (0-10 %) in acetone with saturation behavior, suggesting that H3 DPP+ is stabilized by hydrogen bonding with MeOH even in solution, together with the thermodynamic parameters determined from a van't Hoff plot based on the spectroscopic titration. Femto- and nanosecond laser flash photolysis allowed us to elucidate the photodynamics of H3 DPP+ in intermolecular photoinduced electron transfer (ET) from ferrocene derivatives as one-electron donors to the triplet excited state of H3 DPP+ as an electron acceptor. The second-order rate constants of the ET reactions were evaluated in light of the Marcus theory of ET. The reorganization energy of ET was determined to be 1.87 eV, which is slightly larger than that of H4 DPP2+ in acetonitrile (1.69 eV), due to larger structural change upon ET than that of H4 DPP2+ .

[Evaluation of Norovirus Detection Method Based on a Newly Developed Bioluminescent Enzyme Immunoassay (BLEIA) System].

Noroviruses (NoV) are a major cause of nonbacterial acute gastroenteritis. To efficiently control NoV infection, preventing the transmission of the virus from NoV-infected food-handlers to food may be crucial. At present, reverse-transcription real-time PCR (rRT-PCR) methods may be used as a sensitive method to detect NoV, but the method has the drawbacks of being expensive and time consuming. Other conventional immunological methods such as ELISA and immuno-chromatographic tests are more economical and easier to use than rRT-PCR, but these methods may not be highly sensitive. To overcome these problems, we have developed a novel bioluminescent enzyme immunoassay (BLEIA) system. The system is fully automated and this may enable the rapid, highly sensitive detection of NoV. To practically evaluate the BLEIA, we measured a number of fecal specimens from the patients with acute-gastroenteritis due to NoV infection or healthy adult volunteers in Japan. The performance of the BLEIA was compared with the Loop-Mediated Isothermal Amplification (LAMP) assay and rRT-PCR. The sensitivity, specificity, and correspondence rate of the BLEIA were 93.1% (135/145), 100% (87/87), and 95.7% (222/232), respectively, and those of the LAMP assay were 91.0% (132/145), 98.9% (86/87), and 94.0% (218/232), respectively. A good correlation (r = 0.72) was obtained between the virus loads measured using rRT-PCR and the cut-off index values of the BLEIA, and the sensitivity of the BLEIA was estimated to be 10(5)-10(6) copies/g stool samples. No cross-reactivity toward other closely related or enteric viruses was found. The results indicated that the BLEIA may be applicable for the conventional screening for NoV detection with a large number of fecal specimens from the patients and food-handlers.

[A review of the position adopted by patients when acquiring images of the base of the hamate hook].

The hamate bone, one of the carpal (wrist) bones, has a large uncinate process protruding from the palm side. In sports such as golf and tennis, the hamate bone can break if is subjected to a high external force, such as from the handle of a racquet or club. At our hospital we take X-ray images of the hamate bone from two directions: an axial image through the carpal tunnel and an image at the base of the hamate hook (conventional method). While the conventional method makes it easy to create images of the base of the hamate hook, the patient may suffer pain during image-taking because the hamate bone is pulled to cause radial flexion. We therefore investigated a method of imaging that would create three-dimensional computed tomography (3DCT) images of the base of the hamate hook in which the patient would only have to only rotate the wrist externally and elevate the fore-arm without any radial flexion. Our results suggest that it is possible to obtain images of the base of the hamate hook as clear as those acquired using the conventional method with the patient in a comfortable and painless position taking images at an external rotation angle of 50.3° and a forearm elevation angle of 20.3°.

Prognostic outcome of cervical laser ablation using a holmium yttrium-aluminum-garnet (Ho:YAG) laser for the treatment of cervical intraepithelial neoplasia: A single-center retrospective study.

Objective: Although cervical conization is considered a standard treatment for cervical intraepithelial neoplasia (CIN) 2/3, laser ablation can compensate for the disadvantages of the former. CO2, semiconductor, and holmium yttrium-aluminum-garnet (Ho:YAG) lasers are applied in ablation, but no previous studies have shown the effectiveness of any of these techniques. Here, we retrospectively analyzed the application of the Ho:YAG laser in our hospital to verify its efficacy, and discussed the methods for optimal recurrence detection. Methods: We evaluated the recurrence rates of the pathological condition in patients who underwent laser ablation with a Ho:YAG laser for CIN2/3 at our institution from June 2012 to November 2021. We defined the recurrence as histologically confirmed CIN2 or more advanced stage. Age, preoperative diagnosis, human papillomavirus (HPV) genotype, and postoperative high-risk HPV status were recorded to establish their association with recurrence rates. Results: We performed surgery in 607 patients and the 2-year recurrence rate after interventions was 5.6%. Five patients were diagnosed with invasive cancer at the time of recurrence. Older age significantly correlated with higher risk of recurrence, but preoperative CIN grade and preoperative HPV 16/18 status did not significantly affect it. The postoperative high-risk HPV test was 100% sensitive for detecting recurrence. Conclusions: Laser ablation with the Ho:YAG laser yields promising results. Together with postinterventional management, high-risk HPV test after laser ablation should be conducted after diagnostic conization.This study received the approval from the Ethics Committee of the NHO Tokyo Medical Center (Ethics Committee approval number: R22-067).

Tissue characteristics of residual lesion in patients with acute coronary syndrome caused by plaque rupture versus plaque erosion: a single-center, retrospective, observational study.

Patients with acute coronary syndrome (ACS), frequently caused by plaque rupture (PR), often have vulnerable plaques in residual lesions as well as in culprit lesions. However, whether this occurs in patients with plaque erosion (PE) as well is unknown. We retrospectively analyzed the data of 88 patients with ACS who underwent both optimal coherence tomography (OCT) and intravascular ultrasound (IVUS). Based on plaque morphology of the culprit lesions identified using OCT, patients were classified into PE (n=23) and PR (n=35) groups. The tissue characteristics of residual lesions evaluated using integrated backscatter IVUS were compared between both groups after percutaneous coronary intervention. The PE group had a significantly lower percent lipid volume and a higher percent fibrous volume than the PR group (35.0±17.8% vs 49.2±13.4%, p<0.001; 63.2±17.1% vs 50.3±13.1%, p=0.002, respectively). Receiver operating characteristic curve analysis revealed that percent lipid volume in the residual lesions was a significant discriminant factor in estimating the plaque morphology of the culprit lesion (optimal cut-off value, <43.5%; sensitivity and specificity values were 73.9% and 68.6%, respectively). In conclusion, patients with PE had a significantly lower percent lipid volume and a significantly higher percent fibrous volume in the residual lesions than those with PR, suggesting that the nature of coronary plaques in patients with PE is different from that of those with PR.

Cardiac arrest and post-discharge mortality in patients with myocardial infarction: A large-scale nationwide registry analysis.

Background: Cardiac arrest is a serious complication of acute myocardial infarction. The implementation of contemporary approaches to acute myocardial infarction management, including urgent revascularization procedures, has led to significant improvements in short-term outcomes. However, the extent of post-discharge mortality in patients experiencing cardiac arrest during acute myocardial infarction remains uncertain. This study aimed to determine the post-discharge outcomes of patients with cardiac arrest. Methods: We analysed data from the J-PCI OUTCOME registry, a Japanese prospectively planed, observational, multicentre, national registry of percutaneous coronary intervention involving consecutive patients from 172 institutions who underwent percutaneous coronary intervention and were discharged. Patients who underwent percutaneous coronary intervention for acute myocardial infarction between January 2017 and December 2018 and survived for 30 days were included. Mortality in patients with and without cardiac arrest from 30 days to 1 year after percutaneous coronary intervention for acute myocardial infarction was compared. Results: Of the 26,909 patients who survived for 30 days after percutaneous coronary intervention for acute myocardial infarction, 1,567 (5.8%) had cardiac arrest at the onset of acute myocardial infarction. Patients with cardiac arrest were younger and more likely to be males than patients without cardiac arrest. The 1-year all-cause mortality was significantly higher in patients with cardiac arrest than in those without (11.9% vs. 2.8%, p < 0.001) for all age groups. Multivariable analysis showed that cardiac arrest was an independent predictor of all-cause long-term mortality (hazard ratio: 2.94; 95% confidence interval: 2.29-3.76). Conclusions: Patients with acute myocardial infarction and concomitant cardiac arrest have a worse prognosis for up to 1 year after percutaneous coronary intervention than patients without cardiac arrest.

Spontaneous onset of nonalcoholic steatohepatitis and hepatocellular carcinoma in a mouse model of metabolic syndrome.

Metabolic syndrome is a worldwide healthcare issue and a dominant risk factor for the development of incurable diseases that affect the entire body. The hepatic manifestations of this syndrome include nonalcoholic fatty liver disease (NAFLD) and its progressive variant nonalcoholic steatohepatitis (NASH). The basic pathogenesis of NAFLD/NASH remains controversial because it is difficult to clarify the disease process of NASH on the basis of metabolic syndrome alone. To determine the pathogenesis and effective treatment, an excellent animal model of NASH is required. Tsumura Suzuki obese diabetes (TSOD) male mice spontaneously develop diabetes mellitus, obesity, glucosuria, hyperglycemia, and hyperinsulinemia without any special treatments such as gene manipulation. In this study, we examined the histopathological characteristics of visceral fat and liver of 56 male TSOD mice aged 4-17 months and 9 male Tsumura Suzuki non-obesity (control) mice aged 6-12 months. In the visceral fat, enlargement of adipocytes and perivascular and pericapsular CD8-positive lymphoid aggregation were observed in 4-month-old mice. Abnormal expression of tumor necrosis factor-α, interleukin-6, and lipid peroxidation endo products was observed in macrophages. In the liver, microvesicular steatosis, hepatocellular ballooning, and Mallory bodies were observed in 4-month-old mice, with severity worsening with increasing time. These pathological findings in the liver mimic those seen in patients with NASH. Interestingly, small liver nodules with high cellularity and absence of portal tracts were frequently observed after 12 months. Most of them showed nuclear and structural atypia, and mimicked human hepatocellular carcinoma. The degree of steatosis in the non-tumor portions of the liver improved when the liver nodules developed. These findings were not observed in control mice. Here, we report that TSOD male mice spontaneously developed NAFLD without any special treatment, and that these mice are a valuable model for assessing NASH and NASH carcinogenesis owing to metabolic syndrome.