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Tatsuji Komatsu

Nagasaki Medical Center

Publishes on Liver Diseases and Immunity, Liver Disease Diagnosis and Treatment, Hepatitis C virus research. 65 papers and 2.5k citations.

65Publications
2.5kTotal Citations

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Anti-gp210 and anti-centromere antibodies are different risk factors for the progression of primary biliary cirrhosis
Cited by 361Open Access

UNLABELLED: The predictive role of antinuclear antibodies (ANAs) remains elusive in the long-term outcome of primary biliary cirrhosis (PBC). The progression of PBC was evaluated in association with ANAs using stepwise Cox proportional hazard regression and an unconditional stepwise logistic regression model based on the data of 276 biopsy-proven, definite PBC patients who have been registered to the National Hospital Organization Study Group for Liver Disease in Japan (NHOSLJ). When death of hepatic failure/liver transplantation (LT) was defined as an end-point, positive anti-gp210 antibodies (Hazard ratio (HR) = 6.742, 95% confidence interval (CI): 2.408, 18.877), the late stage (Scheuer's stage 3, 4) (HR = 4.285, 95% CI:1.682,10.913) and male sex (HR = 3.266, 95% CI: 1.321,8.075) were significant risk factors at the time of initial liver biopsy. When clinical progression to death of hepatic failure/LT (i.e., hepatic failure type progression) or to the development of esophageal varices or hepatocellular carcinoma without developing jaundice (Total bilirubin < 1.5 mg/dL) (i.e., portal hypertension type progression) was defined as an end-point in the early stage (Scheuer's stage 1, 2) PBC patients, positive anti-gp210 antibodies was a significant risk factor for hepatic failure type progression [odds ratio (OR) = 33.777, 95% CI: 5.930, 636.745], whereas positive anti-centromere antibodies was a significant risk factor for portal hypertension type progression (OR = 4.202, 95% CI: 1.307, 14.763). Histologically, positive anti-gp210 antibodies was most significantly associated with more severe interface hepatitis and lobular inflammation, whereas positive anticentromere antibodies was most significantly associated with more severe ductular reaction. CONCLUSION: These results indicate 2 different progression types in PBC, hepatic failure type and portal hypertension type progression, which may be represented by positive-anti-gp210 and positive-anticentromere antibodies, respectively.

A novel costimulatory factor for gamma interferon induction found in the livers of mice causes endotoxic shock
Haruki Okamura, Kumiko Nagata, Tatsuji Komatsu et al.|Infection and Immunity|1995
Cited by 342Open Access

Administration of monoclonal anti-CD3 antibody to mice treated with Propionibacterium acnes induced secretion of a high level of gamma interferon (IFN-gamma) into the circulation system, while it induced no significant release in untreated mice. In order to analyze this high-level induction of IFN-gamma in these bacterium-treated mice, we investigated the factors that might be involved. An activity that induces IFN-gamma in T cells was observed in the liver extracts of mice treated with P. acnes and subsequently challenged with lipopolysaccharide. Here, we purified an IFN-gamma-inducing factor from the liver extract to homogeneity and characterized it. Its molecular mass was 18 to 19 kDa, and its pI was 4.9. The amino acid sequence of the NH2-terminal portion was determined and shown to have no similarities to any protein in the EMBL, GenBank, and PIR data bases. The same molecule was also demonstrated in the serum factor that was previously reported to have an IFN-gamma-inducing activity and to have an apparent molecular mass of 75 kDa. Moreover, the activity of this serum factor was recovered in the fraction containing the 18- to 19-kDa protein under reducing conditions and was shown to have the same NH2-terminal amino acid sequence as that of the factor from the liver extract. In addition to the ability to induce IFN-gamma, this protein augmented T-cell proliferation and NK activity in the spleen cells. Thus, several of its biological activities were apparently similar to those of interleukin-12. These results indicated that this novel protein, which exhibited marked costimulatory activity on IFN-gamma production in vitro, was elevated vivo in response to P. acnes treatment. This factor, probably released from the producing cells by lipopolysaccharide stimuli, may be involved in the high-level induction of IFN-gamma in the P. acnes-treated mice.

Real impact of liver cirrhosis on the development of hepatocellular carcinoma in various liver diseases—meta‐analytic assessment
Kazuo Tarao, Akito Nozaki, Takaaki Ikeda et al.|Cancer Medicine|2019
Cited by 200Open Access

BACKGROUND: It is well known that the incidence of developing hepatocelluler carcinoma (HCC) is increased in liver cirrhosis of different etiologies. However, comparison of HCC incidence in various liver diseases has not yet been estimated. We surveyed this comparison. METHODS: The PubMed database was examined (1989-2017) for studies published in English language regarding the prospective follow-up results for the development of HCC in various liver diseases. A meta-analysis was performed for each liver disease. RESULTS: The annual incidence (%) of HCC in the non-cirrhotic stage and cirrhotic stage, and the ratio of HCC incidence in the cirrhotic stage/non-cirrhotic stage were as follows. (a) hepatitis B virus liver disease: 0.37%→3.23% (8.73-fold), (b) hepatitis C virus liver diseases: 0.68%→4.81% (7.07-fold), (c) primary biliary cholangitis (0.26%→1.79%, 6.88-fold), (d) autoimmune hepatitis (0.19%→0.53%, 2.79-fold), and (e) NASH (0.03%→1.35%, 45.00-fold). Regarding primary hemochromatosis and alcoholic liver diseases, only follow-up studies in the cirrhotic stage were presented, 1.20% and 2.06%, respectively. CONCLUSIONS: When the liver diseases advance to cirrhosis, the incidence of HCC is markedly increased. The development of HCC must be closely monitored by ultrasonography, magnetic resonance imaging, and computed tomography, irrespective of the different kinds of liver diseases.

Gastrointestinal Cancer Stage at Diagnosis Before and During the COVID-19 Pandemic in Japan
Kento Kuzuu, Noboru Misawa, Keiichi Ashikari et al.|JAMA Network Open|2021
Cited by 143Open Access

Importance: The COVID-19 pandemic has delayed medical consultations, possibly leading to the diagnosis of gastrointestinal cancer at advanced stages. Objective: To evaluate stage at diagnosis among patients with gastrointestinal cancer in Japan before and during the COVID-19 pandemic. Design, Setting, and Participants: This retrospective cohort study included patients in a hospital-based cancer registry who were diagnosed with gastrointestinal cancer (ie, esophageal, gastric, colorectal, pancreatic, liver, and biliary tract cancers) between January 2016 and December 2020 at 2 tertiary Japanese hospitals. Exposures: The pre-COVID-19 period was defined as January 2017 to February 2020, and the COVID-19 period was defined as March 2020 to December 2020. Main Outcome and Measure: Monthly numbers of patients with newly diagnosed cancer were aggregated, classified by stage, and compared. Results: The study evaluated 5167 patients, including 4218 patients (2825 [67.0%] men; mean [SD] age, 71.3 [10.9] years) in the pre-COVID-19 period and 949 patients (607 [64.0%] men; mean [SD] age, 71.8 [10.7] years) in the COVID-19 period. Comparing the pre-COVID-19 period with the COVID-19 period, significant decreases were observed in the mean (SD) number of patients with newly diagnosed gastric cancer (30.63 [6.62] patients/month vs 22.40 [5.85] patients/month; -26.87% change; P < .001) and colorectal cancer (41.61 [6.81] patients/month vs 36.00 [6.72] patients/month; -13.47% change; P = .03). Significant decreases were also observed in the mean (SD) number of cases of stage I gastric cancer (21.55 [5.66] cases/month vs 13.90 [5.99] cases/month; -35.51% change; P < .001), stage 0 colorectal cancer (10.58 [3.36] cases/month vs 7.10 [4.10] cases/month; -32.89% change; P = .008), and stage I colorectal cancer (10.16 [3.14] cases/month vs 6.70 [2.91] cases/month; -34.04% change; P = .003). No significant increases were observed for esophageal, gastric, pancreatic, liver, or biliary tract cancers. A significant decrease was observed in the mean (SD) number of cases per month of stage II colorectal cancer (7.42 [3.06] cases/month vs 4.80 [1.75] cases/month; -35.32% change; P = .01); a significant increase was observed for the mean (SD) number of cases per month of stage III colorectal cancer (7.18 [2.85] cases/month vs 12.10 [2.42] cases/month; 68.42% change; P < .001). Conclusions and Relevance: In this cohort study of patients in a hospital-based cancer registry form Japan, significantly fewer patients were diagnosed with stage I gastric and colorectal cancers during the COVID-19 pandemic. Thus, the number of screening-detected cancers might have decreased, and colorectal cancer may have been diagnosed at more advanced stages.