Increase in the frequency of community-acquired methicillin-resistant Staphylococcus aureus clones among inpatients of acute care hospitals in the Kyoto and Shiga regions, Japan.

BACKGROUND: Specific epidemic clones of hospital-acquired methicillin-resistant Staphylococcus aureus (HA-MRSA) are responsible for the worldwide spread of MRSA. However, in recent years, the isolation of community-acquired MRSA (CA-MRSA) clones has been increasing. We investigated the latest molecular epidemiology trends of HA-MRSA and CA-MRSA clones in the Kyoto and Shiga regions, Japan. MATERIALS AND METHODS: All nonduplicate MRSA isolates obtained from the clinical specimens of inpatients at four acute care hospitals in the Kyoto and Shiga regions between 2014 and 2019 were typed using the PCR-based open reading frame typing (POT) method. CA-MRSA and HA-MRSA were classified according to the POT1 values. We performed whole-genome sequencing analysis for representative isolates displaying common POT types. RESULTS: A total of 2413 isolates were included in the study, comprising 1730 nosocomial and 683 nonnosocomial isolates. The rates of HA-MRSA decreased from 50.2% in 2014 to 19.0% in 2019, while those of CA-MRSA increased from 44.7% to 76.4% (p < 0.001). Isolates belonging to the most common 10 POT types (CA-MRSA, n = 6; HA-MRSA, n = 4) accounted for 42% of the isolates studied and were obtained from 3 or more hospitals. Whole-genome sequencing analysis showed that the common CA-MRSA isolates with POT types 106-137-80, 106-9-80, 106-9-2, and 106-137-2, those with POT types 106-183-37 and 106-129-5, and HA-MRSA isolates with POT types 93-191-103, 93-157-127, 93-137-103, and 93-223-111 belonged to ST8-SCCmecIV, ST1-SCCmecIV, and ST764-SCCmecII, respectively. CONCLUSION: A recent clonal shift from HA-MRSA to CA-MRSA occurred, and specific regional clones were prevalent among inpatients in the Kyoto and Shiga regions.

Association of Alcohol Consumption With Fat Deposition in a Community-Based Sample of Japanese Men: The Shiga Epidemiological Study of Subclinical Atherosclerosis (SESSA).

BACKGROUND: Excessive alcohol intake has been shown to be associated with cardiovascular disease via metabolic pathways. However, the relationship between alcohol intake and obesity has not been fully elucidated. We aimed to examine the association of alcohol consumption with fat deposition and anthropometric measures. METHODS: From 2006-2008, we conducted a cross-sectional study in a population-based sample of Japanese men aged 40 through 79 years. Areas of abdominal visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) were calculated using computed tomography imaging. Based on a questionnaire, we classified participants into five groups according to weekly alcohol consumption, excluding former drinkers: non-drinkers (0 g/week), 0.1-160.9, 161-321.9, 322-482.9, and ≥483 g/week. Multivariable linear regression was used to estimate adjusted means of obesity indices for each group. RESULTS: We analyzed 998 men (mean age and body mass index [BMI], 63.8 years and 23.6 kg/m2, respectively). Higher weekly alcohol consumption was strongly and significantly associated with higher abdominal VAT area, percentage of VAT, and VAT-to-SAT ratio (all P for trend <0.001), and also with waist circumferences and waist-to-hip ratio (P for trend = 0.042 and 0.007, respectively). These associations remained significant after further adjustment for BMI, whereas alcohol consumption had no significant association with abdominal SAT area. CONCLUSIONS: Higher alcohol consumption was associated with higher VAT area, VAT%, and VAT-to-SAT ratio, independent of confounders, including BMI, in general Japanese men. These results suggest that alcohol consumption may have a potential adverse effect on visceral fat deposition.

Effect of blood decrease on micafungin disposition in rats.

Micafungin (MCFG) is a novel echinocandin-class antifungal agent that extensively undergoes metabolic removal in the liver. In the present study, the influence of decreased blood volume on pharmacokinetic disposition of MCFG was examined using a rat model prepared by phlebotomy. In phlebotomized rats, hematocrit level and plasma albumin concentration were decreased by 50 and 15%, respectively. Regarding the pharmacokinetic parameters of MCFG, there were no significant differences in the total body clearance (CL(tot)) and elimination rate constant (k (e)) between control and phlebotomized rat groups. A slight increase was observed in the apparent volume of distribution at steady-state (Vd(ss)), but the degree of change was minimal. These findings demonstrate that the elimination capacity for MCFG is only slightly affected by severe anemia and moderate hypoalbuminemia, and provide experimental evidence for the preceding clinical studies suggesting that neither hematocrit level nor serum albumin concentration is a contributory factor for the metabolic clearance of MCFG.

Change in blood tacrolimus concentration by fluctuation of renal function in a bone marrow transplant patient.

The authors report a case showing a marked change in blood tacrolimus concentration due to modification of renal function in a bone marrow transplant recipient. Blood tacrolimus concentration was well controlled after transplantation, but an approximately threefold increase in the concentration was observed on day 10 even though the dosage was unchanged. Although there were no pronounced changes in hepatic enzyme activities in serum, marked elevations of renal function test values were noted; concentrations of serum creatinine (SCr) and blood urea nitrogen (BUN) were increased by more than 300% from the original levels. The tacrolimus concentration was gradually decreased by the dose reduction, but the dose-adjusted tacrolimus blood concentration (C/D) was increased contrary to the decreased tacrolimus concentration. The C/D of tacrolimus also began to decline from several days after the recovery of Scr and BUN levels and returned to the basal level. Our finding suggests that renal function has a significant effect on the pharmacokinetic disposition of tacrolimus, although this agent is almost completely eliminated by hepatic metabolism. Careful attention should be paid to alteration in tacrolimus blood concentration, especially when renal function fluctuates during post-transplant immunosuppressive therapy.

[Evaluation of a Two-day Hospital On-site Training Program for Community Pharmacists: Approach to Facilitate Collaboration among Community Healthcare Professionals].

　The importance of community-based care systems has increased due to the highly aging population and diversity of disease. To enhance the cooperation among healthcare professionals in community-based care systems, a two-day on-site training program for community pharmacists based on a multidisciplinary team approach was conducted at the Medical Science Hospital of Shiga University from April 2015 to March 2017. There were two professional courses in this training program: the palliative care course and nutrition support course. Both courses consisted of common pharmaceutical care training as follows: regional cooperation among healthcare professionals, pharmacist's clinical activities in the ward, pressure ulcer care, infection control, and aseptic technique for parenteral solutions. Each course was limited to 2 participants. A questionnaire was given to participants in the training program. Seventy-five pharmacists participated in the training and all of them answered the questionnaire. According to the questionnaire, 86% of participants felt that 2 days was an appropriate term for the training program. Positive answers regarding the content of each program and overall satisfaction were given by 100% and 99% of the participants, respectively. In the categorical classification of free comments regarding the expected change in pharmacy practice after the training, both "support for patients under nutritional treatment" and "cooperation with other medical staff" were answered by 24 participants. These results suggested that the 2-day on-site training for community pharmacists facilitated cooperation among healthcare professionals in the community.

Mendelian randomization analysis in three Japanese populations supports a causal role of alcohol consumption in lowering low-density lipid cholesterol levels and particle numbers.

BACKGROUND AND AIMS: While alcohol consumption is known to increase plasma high-density lipoprotein (HDL) cholesterol levels, its relationship with low-density lipoprotein (LDL) cholesterol levels is unclear. Aldehyde dehydrogenase 2 (ALDH2) is a rate-controlling enzyme in alcohol metabolism, but a large number of Japanese people have the inactive allele. Here, we conducted a Mendelian randomization analysis using the ALDH2 genotype to clarify a causal role of alcohol on circulating cholesterol levels and lipoprotein particle numbers. METHODS: This study was conducted in three independent general Japanese populations (men, n = 2289; women, n = 1940; mean age 63.3 ± 11.2 years). Alcohol consumption was assessed using a questionnaire. Lipoprotein particle numbers were determined by nuclear magnetic resonance spectroscopy. RESULTS: Alcohol consumption increased linearly in proportion to the number of subjects carrying the enzymatically active *1 allele in men (p < 0.001). The *1 allele was also positively associated with HDL cholesterol level (adjusted mean ± standard error, *1*1: 60 ± 0.5, *1*2: 56 ± 0.6, *2*2: 55 ± 1.3 mg/dl, p < 0.001) and inversely associated with LDL cholesterol level (116 ± 0.9, 124 ± 1.1, 130 ± 2.6 mg/dl, p < 0.001). The *1 allele was also positively associated with HDL particle numbers (per-allele: 2.60 ± 0.32 µmol/l, p < 0.001) and inversely associated with LDL particle numbers (-67.8 ± 19.6 nmol/l, p = 0.001). Additional Mendelian randomization analysis failed to clarify the involvement of cholesteryl ester transfer protein in alcohol-related changes in lipoprotein cholesterol levels. No significant association was observed in women, presumably due to their small amount of alcohol intake. CONCLUSIONS: Alcohol consumption has a causal role in not only increasing HDL cholesterol levels but also decreasing LDL cholesterol levels and particle numbers.

Decrease in oral bioavailability of ciclosporin by intravenous pulse of methylprednisolone succinate in rats.

We examined the effects of high-dose methylprednisolone on the bioavailability of orally administered ciclosporin in rats. To emulate the clinical protocol of methylprednisolone pulse therapy, methylprednisolone sodium succinate (MPS), a prodrug of methylprednisolone, was intravenously administered as repeated doses (66.3 mg kg(-1)) for 3 days. The area under the blood ciclosporin concentration versus time curve after oral administration was significantly reduced by 60% by pulse treatment with MPS. Based on our previous finding that the total body clearance of ciclosporin was reduced by about 20% by the same methylprednisolone pulse protocol, the extent of reduction in the oral bioavailability of ciclosporin was estimated to be approximately 50%, indicating a drug interaction between high-dose methylprednisolone and orally administered ciclosporin, which affected the absorption process. In rats treated with MPS, an in-situ efflux experiment using rhodamine-123 demonstrated that the reverse transport function of P-glycoprotein (P-gp) in the small intestine was significantly enhanced, although there was no significant increase in the intestinal microsomal activity of triazolam alpha- and 4-hydroxylation, metabolic probes for CYP3A. In addition, a significant decrease was observed in the amount of secreted bile acids serving as an enhancer of gastrointestinal absorption of ciclosporin in MPS treatment. To directly estimate the absorptive capacity, an in-situ absorption test was conducted using a closed-loop of small intestine in control and MPS-treated rats. Intestinal absorption of ciclosporin was significantly decreased, not only in the absence of bile flow but also by treatment with MPS, which well reflected the change in the in-vivo pharmacokinetic behaviour of ciclosporin after methylprednisolone pulsing. These results demonstrate that bioavailability of ciclosporin is markedly reduced by MPS pulse treatment, and the mechanism of this interaction was confirmed to involve enhancement of small-intestinal P-gp function and decrease in bile secretion.

Influence of intravenous methylprednisolone pulse treatment on the disposition of ciclosporin and hepatic CYP3A activity in rats.

We examined the effects of high-dose methylprednisolone (MP) on the disposition of ciclosporin (CsA) and hepatic microsomal CYP3A activity using rats. Methylprednisolone sodium succinate (MPS), a prodrug of MP, was intravenously administered as repeated doses (66.3 mg kg(-1)) for 3 days or as a single dose. In MP-treated rats, a significant increase was observed in the total body clearance (CL(tot)) and elimination rate constant (Ke) of intravenously administered CsA. The enzyme activities of triazolam hydroxylations and erythromycin N-demethylation in hepatic microsomes were also enhanced by about 50% by MP treatment, suggesting that the alteration in the CsA pharmacokinetics was due to significant induction of the hepatic CYP3A responsible for the metabolic conversion of CsA. In contrast, no significant changes in the values of CL(tot) and Ke were found following a single treatment with MP. On the other hand, MP inhibited the CYP3A-mediated triazolam hydroxylations in a concentration-dependent manner. The difference between the in-vivo and in-vitro inhibitory behaviours of MP was attributed to the rapid elimination of MP after biotransformation from MPS because the plasma MP concentration decreased with a half-life of 15 min immediately after reaching a level close to the inhibition constant for the triazolam 4-hydroxylation reaction (32.4 microM). Although there is a general consideration that MP cannot act as an enzyme inducer at maintenance doses, the present results strongly suggest that high-dose MP is likely to interact pharmacokinetically with CsA by inducing hepatic CYP3A. These results may provide basic explanations for the clinical experience that blood CsA levels are reduced during MP pulse therapy.

Reduced elimination clearance of micafungin in rats with cholestatic hyperbilirubinemia.

We examined whether the pharmacokinetic disposition of micafungin (MCFG), an echinocandin class antifungal agent, is altered in hyperbilirubinemia using a rat model prepared by bile duct ligation (BDL). Serum bilirubin levels were increased depending upon the duration of BDL. The elimination rate constant and total body clearance (CL(tot)) of MCFG were reduced by 24% and 16%, respectively, after BDL for 1 h, but there was no significant change in the apparent volume of distribution at steady-state. The degree of reduction in the CL(tot) was much greater 7 days after BDL as compared with that 1 h after BDL (44% vs. 16%). However, the proportion of the biliary clearance in the CL(tot) was about 10%. This is similar to the extent of decrease in the CL(tot) by occlusion of the bile duct, demonstrating that decreased biliary excretion of MCFG makes only a minor contribution to its pharmacokinetic change. These findings suggest that the metabolic capacity of MCFG is markedly impaired in hepatic hypofunction secondary to hyperbilirubinemia, providing a fundamental explanation for the previous clinical report that there is a significant correlation between dose-adjusted plasma MCFG concentration and serum bilirubin levels.

Impact of plasma exchange on pharmacokinetic disposition of micafungin.

Change in the pharmacokinetic disposition of an antifungal agent micafungin (MCFG) by 8-hour plasma exchange (PE) with 3200 mL replacement was examined in a stem cell transplant recipient. On pharmacokinetic analysis of the time course of the serum concentrations of MCFG, it was determined that PE shortened the elimination half-life of MCFG from 16.5 hours to 6.3 hours. Total clearance (CL(tot)) was increased from 0.366 L/h to 0.932 L/h by PE. PE-dependent clearance (CL(pe)) accounted for approximately two-thirds of CL(tot), and PE was found to contribute to the removal of nearly 40% of the total body store of MCFG. It was confirmed that a significant amount of MCFG was excluded into apheresed plasma waste. In addition, adsorption of MCFG onto plasma-separating membrane was strongly suggested, because the CL(pe) exceeded the rate of plasma apheresis and MCFG concentrations in apheresed plasma were lower than those in circulating blood collected at the same time. The marked elimination of MCFG during PE can be explained by its low volume of distribution and high affinity for serum proteins. Judging from these findings as well as those of other reports, MCFG can be considered one of the drugs most susceptible to removal by PE. Our findings suggest that an increment in the regular dose of MCFG would be required at the next administration after PE.

Pharmacokinetic behavior of micafungin in rats with carbon tetrachloride-induced acute hepatic failure.

We examined the pharmacokinetic behavior of micafungin, a novel antifungal agent, in rats receiving carbon tetrachloride (CCl4) at a single dose of 2.5 ml/kg. There was no significant change in the total clearance (CL(tot)) in CCl4-treated rats, while the steady-state volume of distribution (Vd(ss)) was significantly increased by CCl4 treatment. Alteration in the serum unbound fraction of micafungin after CCl4 treatment was unlikely in light of the serum albumin, bilirubin, creatinine, and urea nitrogen. The increased Vd(ss) was attributable to augmentation in the accessibility of micafungin to peripheral tissue without impairment of the intrinsic clearance, because slight enhancement of the tissue distribution of micafungin was confirmed following CCl4 treatment.

Sensitive and simultaneous determination of HIV protease inhibitors in rat biological samples by liquid chromatography-mass spectrometry.

A sensitive and simultaneous liquid chromatographic-mass spectrometric (LC/MS) method for the determination of current four HIV protease inhibitors (PIs), indinavir (IDV), saquinavir (SQV), nelfinavir (NFV) and amprenavir (APV) in rat plasma and liver dialysate by a microdialysis method was described. An isocratic LC/MS method in combination with atmospheric pressure chemical ionization was developed for the determination of these four PIs in biological samples in the same run. The analytes including an internal standard were extracted from 100 microL of plasma or 150 microL of liver dialysate samples by salting-out with 100 microL of ice-cold 2 M K(3)PO(4) followed by ether extraction. The separation of analytes was carried out on a reversed-phase semi-micro column using 50% of acetonitrile containing 1% acetic acid as mobile phase at a flow rate of 0.2mL/min(-1). The separation was completed within 5 min. Precision, recovery and limits of detection indicated that the method was suitable for the quantitative determination of these PIs in rat plasma or liver dialysate. This simple, sensitive and highly specific LC/MS method is suitable for pharmacokinetic studies and therapeutic drug monitoring in AIDS patients who receive double protease therapy.