Hideki Takami

Study for determination of the optimal cessation period of therapy with anti-platelet agents prior to invasive endoscopic procedures

BackgroundAnti-platelet agents are widely used for the treatment and prevention of thrombotic diseases. On the other hand, continuation of anti-platelet agents increases the risk of hemorrhagic complications in gastrointestinal endoscopy, and cessation of anti-platelet agents exposes the patient to the risk of thromboembolism. Only a few studies have actually studied the whether a cessation period is required prior to endoscopic procedures and if so, the optional duration of the period. The present study assessed the time course of primary hemostasis after the cessation of anti-platelet agents.MethodsEleven healthy men (age range, 19–29 years) were assigned to each of the following regimens: aspirin (ASA; 100 mg/day), ticlopidine (TP; 300 mg/day), and a combination of ASA (100 mg/day) and TP (300 mg/day) for 7 days. There was a washout period of more than 3 weeks between each regimen. A quantitative bleeding time test (QBT test) and platelet aggregation test were performed before the beginning of administration, on the last day of administration, and at 1, 3, and 5 days after cessation, and also at 7 days after cessation for the combination regimen.ResultsThe average bleeding time (BT) and total bleeding loss volume (Tv) of the 11 subjects after administration of the three regimens were significantly increased compared with those before administration. With the administration of ASA, increases of BT and Tv at 3 days after cessation were not significant. The Tv at 5 days after cessation of TP was not significantly increased. With the combination regimen, the BT and Tv at 7 days after cessation were not significantly increased.ConclusionsA 3-day cessation period for ASA, a 5-day cessation period for TP, and a 7-day cessation period for ASA + TP administration seem to be sufficient.

Long-term Survivors with Adult Acute Leukemia in Complete Remission: Complications and Return to Work

For addressing, and eventually being able to predict and prevent, both disease-related complications and changes in social status in long-term acute leukemia survivors, the follow-up is the most important factor after treatment. To this end, we assessed the complications following the attainment of complete remission in adult acute leukemia patients and the changes in social status of patients surviving more than 5 years after disease onset. In our study population of 42 survivors, 24 (57.1%) suffered from various combinations of 18 types of identified complications including posttransfusion hepatitis, diabetes mellitus, and idiopathic osteonecrosis. Regarding fertility, 9 live births were recorded in this cohort, from 2 female patients and the partner of a male patient. Of these 42 long-term survivors, at the time of this report 48.5% were working full- or part-time, 9.0% were unemployed, 30.3% were homemakers, and 12.2% were retired.

UDP/P2Y6 receptor signaling regulates IgE-dependent degranulation in human basophils

BACKGROUND P2Y purinergic receptors (P2YR) are G protein-coupled receptors that are stimulated by extracellular nucleotides. They mediate cellular effects by regulating cAMP production, protein kinase C activation, inositol trisphosphate generation, and Ca2+ release from intracellular stores. The P2Y6 receptor of this family is selectively stimulated by UDP, and selectively inhibited by MRS2578. In the present study, we examined the effect of UDP/P2Y6 receptor signaling on IgE-dependent degranulation in human basophils. METHODS Basophils were purified from human peripheral blood. The mRNA expression of genes encoding P2YR and ecto-nucleoside triphosphate diphosphohydrolase (ENTPDase) was measured by RT-PCR. Intracellular Ca2+ influx via UDP/P2Y6 receptor signaling in basophils was detected using a calcium probe. The effect of UDP/P2Y6 receptor signaling on IgE-dependent degranulation in basophils was confirmed by measuring CD63 expression by flow cytometry. Autocrine secretion of nucleotides was detected by HPLC analysis. RESULTS We showed that purified basophils express P2Y6 mRNA and that UDP increased intracellular Ca2+, which was reduced by MRS2578 treatment. UDP promoted IgE-dependent degranulation. Furthermore, MRS2578 inhibited IgE-dependent degranulation in basophils. HPLC analysis indicated that basophils spontaneously secrete UTP. In addition, basophils expressed the extracellular nucleotide hydrolases ENTPDase2, ENTPDase3, and ENTPDase8. CONCLUSIONS This study showed that UDP/P2Y6 receptor signaling is involved in the regulation of IgE-dependent degranulation in basophils, which might stimulate the P2Y6 receptor via the autocrine secretion of UTP. Thus, this receptor represents a potential target to regulate IgE-dependent degranulation in basophils during allergic diseases.

Effect of alcohol drinking and cigarette smoking on neutrophil functions in adults.

In recent years, the effects of smoking and excessive alcohol consumption on immune function have been studied, due to a high prevalence of infection or cancer in heavy drinkers, and the combination of smoking and drinking was considered to be a carcinogenic risk. However, the effect of smoking and drinking on systemic immune function has yet to be clearly understood. In this study, we investigated neutrophil functions (reactive oxygen species (ROS) productive activity, phagocytic ability and serum opsonic activity) and their relationship with alcohol consumption or amount of smoking. In total there were 731 male and female adult subjects who participated in the Iwaki Health Promotion Project in 2005. Multiple regression analysis showed a trend of increased ROS production in male subjects and a statistically significant decrease was observed in phagocytic activity caused by smoking in female subjects. In other words, oxidative stress caused by smoking in male subjects may be involved in ROS production from neutrophils. Decreased phagocytic activity of neutrophils caused by smoking suggests that host defense functions were impaired in female subjects. A relationship between neutrophil functions and the amount of alcohol consumption was not observed.

Genetic analyses of the fusion protein genes in human parainfluenza virus types 1 and 3 among patients with acute respiratory infections in Eastern Japan from 2011 to 2015

PURPOSE To genetically explorer the fusion protein gene (F) in human parainfluenza virus type 1 (HPIV1) and type 3 (HPIV3) strains, we analyzed them in the patients with acute respiratory infections (ARI) in Eastern Japan from 2011 to 2015. METHODOLOGY We constructed phylogenetic trees based on the HPIV and HPIV3 F gene using the maximum likelihood method and conducted p-distance, and selective pressure analyses. We also predicted the linear epitopes of the protein in the prototype strains. Furthermore, we mapped the amino acid substitutions of the proteins.Results/Key findings:Nineteen strains of HPIV1 and 53 strains of HPIV3 were detected among the clinical ARI cases. The phylogenetic trees indicated that the HPIV1 and HPIV3 strains were classified into clusters II and III, and cluster C, respectively. The p-distance values of the HPIV1 and HPIV3 F genes were <0.03. Two positive selection sites were inferred in the HPIV1 (aa8 and aa10), and one positive selection site was inferred in the HPIV3 (aa108); but over 10 negative selection sites were inferred. Four epitopes were predicted for the HPIV1 prototype strains, while five epitopes were predicted for the HPIV3 prototype strain. A positive selection site (aa108), or the HPIV3 F protein was involved in the predicted epitope. Additionally, we found that an amino acid substitution (R73K) in the LC76627 HPIV3 strain presumably may affect the resistance to neutralization by antibodies. CONCLUSION The F gene of the HPIV1 and HPIV3 were relatively well conserved in the Eastern part of Japan during the investigation period.Purpose. To genetically explore the fusion protein gene (F) in human parainfluenza virus type 1 (HPIV1) and type 3 (HPIV3) strains, we analysed them in patients with acute respiratory infections in Eastern Japan from 2011 to 2015. Methodology. We constructed phylogenetic trees based on the HPIV and HPIV3 F gene using the maximum likelihood method and conducted P‐distance and selective pressure analyses. We also predicted the linear epitopes of the protein in the prototype strains. Furthermore, we mapped the amino acid substitutions of the proteins. Results. Nineteen strains of HPIV1 and 53 strains of HPIV3 were detected among the clinical acute respiratory infection cases. The phylogenetic trees indicated that the HPIV1 and HPIV3 strains were classified into clusters II and III and cluster C, respectively. The P‐distance values of the HPIV1 and HPIV3 F genes were <0.03. Two positive selection sites were inferred in the HPIV1 (aa 8 and aa 10), and one positive selection site was inferred in the HPIV3 (aa 108), but over 10 negative selection sites were inferred. Four epitopes were predicted for the HPIV1 prototype strains, while five epitopes were predicted for the HPIV3 prototype strain. A positive selection site (aa 108) or the HPIV3 F protein was involved in the predicted epitope. Additionally, we found that an amino acid substitution (R73K) in the LC76627 HPIV3 strain presumably may affect the resistance to neutralization by antibodies. Conclusion. The F gene of HPIV1 and HPIV3 was relatively well conserved in the eastern part of Japan during the investigation period.

Synergistic disaggregation of platelets by the products of endothelial cells or their analogs.

It is known that some products of endothelial cells or their analogs can attenuate the platelet aggregation response and initiate the platelet disaggregation response. Since platelets are involved in the initiation of many clinically important occlusive vascular diseases, we hypothesized that the endothelial cell products act synergistically to disperse platelet aggregates. In this study we examined the synergistic platelet disaggregating effects among the products of endothelial cells. We used urokinase, prostaglandin I2 (PGI2), and sodium nitroprusside (SNP) (which is the chemical substitute as nitric oxide(NO)-donor) for endothelium-derived relaxing factor (EDRF). Platelet disaggregation rate was increased in a dose-dependent manner and decreased in a time-dependent manner, and the combined use of two or three agents had synergistic effects on platelet disaggregation. Furthermore, flow cytometric analysis showed decreases in the binding of fibrinogen to activated platelets by the addition of PGI2 or SNP. These data revealed that these products or their analogs could inactivate the activated platelets or aggregated platelets by detaching fibrinogen from platelets. In addition our data revealed that PGI2 and SNP can act synergistically with fibrinolytic agents. These findings suggest a potential strategy for improving the efficacy of thrombolytic therapy by a combination of these products or their substitutes.

The expression of TP53 mRNA splice variants relates to progression of cancer in human colorectal cancer

Background: The carcinogenesis of colon and rectum is caused by accumulation of genetic alternation or mutation. Recent works have shown significant biomarkers that include loss of heterozygosity, gene mutations or gene methylation of genomic DNA. Furthermore, it is also reported that the functional analysis of mRNAs and miRNAs are significance for clarification of cancer progress. In this study, we examined the expression of TP53 mutation, TP53 mRNA splice variants, TP53 protein and TP53-related miRNA in human colorectal cancer, and evaluated significance as the clinicopathological biomarker. Design: Tumors were collected from 30 patients diagnosed with primary advanced colorectal cancer. Both genomic DNA and total RNA were extracted with TRIzol reagent, and TP53 mutation was analyzed by direct sequence method. TP53 mRNA splice variants were analyzed by RT-PCR, TP53-related miRNA were analyzed by qRT-PCR, and TP53 protein was detected by immunohistochemistry. Statistical analysis was carried out by SPSS21. Results: TP53 alfa showed significantly low expression in TP53 mutation cancer. TP53 beta showed significantly low expression in TP53 mutation cancer. TP53 gamma showed significantly high expression in TP53 mutation cancer, and it also showed low expression in pTMN stage I + II as compared to pTMN stage III + IV.