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This study was undertaken in order to analyse the immuno-regulatory mechanism of non-responsiveness to hepatitis B (HB) vaccine in healthy individuals. We have reported already that peripheral mononuclear cells (MNC) isolated from anti-HBs sero-positive subjects after booster injection are able to make anti-HBs in vitro by stimulation with pokeweed mitogen (PWM) plus HBsAg. In contrast, under the same conditions, non-responder (NR) MNC failed to produce anti-HBs in vitro, even after an additional injection, although an amount of immunoglobulin was synthesized corresponding with the responder controls. Co-culture experiments carried out with T-cell fractions (T) and non-T-cell fractions (NT) from NR and controls showed: (i) by Week 2 after the last vaccination, NT from NR could hardly be activated to produce anti-HBs; however, by Week 4 significant synthesis of anti-HBs was induced by the stimulation of responder T; (ii) in experiments using responder NT and T from NR, seven out of eight and five out of nine co-cultures were found to make anti-HBs by Weeks 2 and 4, respectively; (iii) T from NR, as well as their culture supernatants, specifically suppressed anti-HBs production of responder MNC, especially by Week 4 after the last vaccination. From these results, it is predicted that the early stage of non-responsiveness in NR is mainly due to a defect of the B-cell repertoire, while that of the late stage is caused by the existence of HBsAg-specific suppressor T cells.

Azithromycin (AZM) is one of 15-membered rings macrolide antibiotics with wide spectrum of antimicrobial efficacy for Gram-positive and -negative bacteria and also atypical bacteria. So far, there had been no reports of the prospective studies evaluating efficacy and safety of AZM infusion in patients with mild or moderate community-acquired pneumonia (CAP). This study was conducted to evaluate prospectively the efficacy and safety of AZM in patients with mild or moderate CAP. AZM 500 mg was intravenously administered once daily, and the clinical efficacy were evaluated by clinical symptoms, peripheral blood laboratory findings and chest X-rays. Sixty-four patients were firstly registered, and eventually 61 and 62 patients were enrolled for the evaluation of clinical efficacy and safety of AZM, respectively. The efficacy of AZM in 61 patients evaluated was 88.5%. In addition, the efficacies of AZM in each pneumonia severity index by A-DROP system by the Japanese Respiratory Society (JRS) guideline in CAP were 85.2% in mild and 91.2% in moderate. Furthermore, the efficacy of AZM in each differentiation between suspicion of bacterial pneumonia and that of atypical pneumonia by JRS guideline in CAP were 91.7% in suspicion of atypical pneumonia, and its efficacy was high than that of bacterial pneumonia. Nineteen patients (20 cases; 15 with liver dysfunction, 4 with diarrhea, 1 with vascular pain) out of 62 patients were reported to have possible adverse effects of AZM. All of the patients with these adverse effects demonstrated mild dysfunction and continued AZM treatment, and these dysfunctions normalized soon after cessation of AZM. In conclusion, AZM is effective drug for patients with mild or moderate CAP, and we believe that it may be one of effective choice in the treatment of CAP patients who need hospitalization.

Levofloxacin (LVFX) is one of respiratory quinolones with wide spectrum of antimicrobial efficacy for Gram-positive and -negative bacteria and also atypical bacteria, and 500 mg of intravenous LVFX infusion has recently been able to use once daily based on pharmacokinetics-pharmacodynamics in Japan. So far, there had been no reports of the prospective studies evaluating efficacy and safety of LVFX in patients with nursing and healthcare-associated pneumonia (NHCAP). This study was conducted to evaluate prospectively the efficacy and safety of LVFX in patients with NHCAP categories B and C (other antibacterial agents were allowed to use with LVFX) according to Japanese guideline for NHCAP by the Japanese Respiratory Society (JRS). LVFX 500 mg was intravenously administered once daily, and the clinical efficacy and safety were evaluated by clinical symptoms, peripheral blood laboratory findings and chest X-rays. Sixty-two patients (average age was 81.2 years old, female/male was 22/40) were firstly registered and evaluated for the safety of LVFX, and eventually 54 patients were enrolled for the evaluation of clinical efficacy of LVFX. The percentage of these 54 patients aged over 65 years old was 96.3%, NHCAP category B/C was 33/21. The efficacy of LVFX in all 54 patients evaluated was 85.2% (categories B/C of NHCAP was 81.8/90.5%). In addition, the efficacies of LVFX in each pneumonia severity category by A-DROP system by JRS in NHCAP patients were 100% in mild, 86.7% in moderate, 77.8% in severe/very severe. Nine patients (2 with liver dysfunction, 6 with renal dysfunction and 1 with thrombocytopenia) out of 62 patients were reported to have possible adverse effects of LVFX. All of the patients with liver and renal dysfunctions after starting LVFX administration demonstrated mild dysfunctions and continued LVFX treatment, and these dysfunctions normalized soon after cessation of LVFX. LVFX was changed to other antibacterial agent in one patient with thrombocytopenia, and also thrombocytopenia was normalized thereafter. In conclusion, LVFX is effective and relatively safe for categories B and C in patients with NHCAP.

This paper reports a series of studies leading to the discovery of a submarine hydrothermal field (called Nakayama Field) at an arc seamount (12∞43￠ N, 143∞32￠ E) in the southernmost part of the Mariana Trough, western Pacific Ocean. We first detected hydrothermal plumes characterized by water column anomalies of temperature, light transmission, Mn, Fe, Al, O2, CH4, and d13C of CH4 above the summit caldera of the seamount. Then deep-tow camera surveys confirmed the existence of hydrothermal activity inside the caldera, and an ROV dive finally discovered white smoker-type fluid venting associated with vent fauna. A high concentration of aluminum in the plume and white smoker-type emissions imply acidic hydrothermal activity similar to that observed at the DESMOS Caldera in the eastern Manus Basin, Papua New Guinea. Anomalously low d13C (CH4) of .38‰ of a vent fluid sample compared to other arc hydrothermal systems along the Izu- Bonin and Mariana Arcs suggests an incorporation of biogenic methane based on a subsurface microbial ecosystem.

Moxifloxacin (MFLX) is a respiratory quinolone, and is effective against not only Gram-positive and negative bacteria but also anaerobes. There has been no prospective studies evaluating the efficacy and safety of MFLX in patients with nursing and healthcare-associated pneumonia (NHCAP). Therefore, we assessed the efficacy and safety of MFLX in patients with NHCAP. NHCAP patients with mild and moderate severity assessed by the A-DROP system in community-acquired pneumonia guideline proposed by Japan Respiratory Society visited our hospitals from April 2011 to March 2012. Clinical symptoms, chest X-ray films and/or computed tomography, peripheral white and red blood cell and platelet counts, serum CRP, AST, ALT, BUN, creatinine were evaluated. Forty patients were eventually evaluated, and average age was 74.1 years old, male/female were 21/19, 92.5% (37/40) of them had one or more comorbidities. Median duration of MFLX administration was 7.1 days (4-15 days). The efficacy of MFLX in all patients was 87.5% (35/40). The efficacies in each age group were 87.9% (aged over 65 years old), 85.7% (aged under 64 years old), and in each pneumonia severity group by the A-DROP system were 91.7% (mild), 85.7% (moderate). Diarrhea and swelling of the breast were observed in one patient (2.5%) after starting MFLX administration. Mild elevated transaminases were observed in three patients (7.5%), and mild renal dysfunction was observed in two patients (5.0%). All abnormally increased levels of transaminases and serum creatinine were recovered after a cessation of MFLX. MFLX is effective and safe in patients with NHCAP.