Mitsuru Yanai

Nihon University, Edo, Tōkyō, Japan

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Publications (40)40.13 Total impact

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    ABSTRACT: Background/Aims: We examined sex differences in prevalence, progression, and improvement in early-stage chronic kidney disease (CKD). Methods: We analyzed data from 533 participants who took 4 consecutive annual CKD detection tests. Results: Urine albumin-creatinine ratio (ACR), estimated glomerular filtration rate (eGFR), and hemoglobin (Hb) at baseline in men with and without CKD and in women with and without CKD were 8.3±6.1, 149.2±310.4, 10.2±5.8, and 96.7±246.8 mg/g Cr; 83.4±14.7, 63.8±18.8, 79.9±13.0, and 69.4±20.0 mL/min/1.73 m(2); and 14.8±1.2, 14.3±1.4, 13.0±1.0, and 13.0±1.2 mg/dL, respectively. ACR levels decreased significantly over time in men and women with CKD and they increased significantly over time in men and women without CKD. eGFR levels in men and women with CKD did not significantly change over time, but they decreased significantly over time in men and women without CKD. CKD prevalence and progression rate were not significantly different between sexes. Among the CKD participants, significantly more women had a "cured" status at 3 years (39.1% vs. 19.4%, P<0.01). Most whose eGFR increased to >60 mL/min/1.73 m(2) at 3 years had values just below those at baseline. Regression analysis showed that change in eGFR correlated significantly with ACR in men with CKD (change in eGFR = -1.707+0.022×ACR, P<0.001, r(2)=0.201) and with Hb and ACR in women with CKD (change in eGFR = 48.870-3.803×Hb + 0.018×ACR, P<0.05, r(2)=0.134). Conclusions: These results suggest that the slight decrease of Hb within a normal range and mild anemia can be managed in women with early-stage CKD. The key baseline for eGFR is 60 mL/min/1.73 m(2). © 2014 S. Karger AG, Basel.
    Kidney and Blood Pressure Research 08/2014; 39(4):279-288. · 1.60 Impact Factor
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    ABSTRACT: A recent report has dealt with geriatric nephrology, including epidemiology and pathophysiology of chronic kidney disease (CKD), attempting to get nephrologists to pay more attention to elderly CKD patients. The aims of this article are to summarize the morphological and functional properties of the aging kidney, and to better understand nephrology care for elderly CKD patients. The kidneys are affected by the aging process, which results in numerous effects on the renal system. In addition, the elderly population is hetereogenous - some have a decline in GFR explained by diseases that complicate aging such as arteriosclerosis with hypertension, whereas in the most of healthy adults the decline in GFR is much more modest and not inevitable. The values for normal estimated glomerular filtration rate (eGFR) in aging population have important implications for the diagnosis of CKD in the elderly. However, the MDRD equation underestimates mean eGFR by 25% and the CKD-EPI equation underestimates mean GFR by 16%. This bias may lead to misclassifying healthy older persons as having CKD. It is also still unknown whether and how age influences the predictive role of other risk factors for end-stage renal disease (ESRD) and death in referred as well as unreferred patients. The risk of ESRD was reported to be higher than the risk of death without ESRD for ages <60 years, and independent of eGFR. Proteinuria significantly increased the risk of ESRD with advancing age. In older patients on nephrology care, the risk of ESRD prevailed over mortality even when eGFR was not severely impaired. Proteinuria increases the risk of ESRD, while the predictive role of other modifiable risk factors was unchanged compared with younger patients. The decision to initiate renal replacement therapy in the elderly is complicated by more challenges than in younger patients. Calorie restriction and Klotho deficiency may be a candidate therapeutic target for attenuating kidney aging. © 2014 S. Karger AG, Basel.
    Kidney and Blood Pressure Research 03/2014; 38(1):109-120. · 1.60 Impact Factor
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    ABSTRACT: Patients and healthcare workers in a Japanese haemodialysis clinic were investigated for nasal carriage of meticillin-resistant Staphylococcus aureus (MRSA). MRSA carriage was found in 10 (8.9%) of 112 patients in the first year and four (3.9%) of 103 patients in the second year. All isolated MRSA samples carried staphylococcal cassette chromosome mec type II or III and classified as clonal complex 5, which were common as healthcare-associated strains. Pulsed-field gel electrophoresis indicated horizontal transmission limited to two pairs of patients in one session. One of 54 healthcare workers carried MRSA genetically unrelated to patients' strains. Infection control measures based on the US Centers for Disease Control and Prevention's recommendation showed limited spread of MRSA in a haemodialysis room.
    The Journal of hospital infection 02/2013; · 3.01 Impact Factor
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    ABSTRACT: Innate immunity is generally impaired in chronic renal failure (CRF). Mannose-binding lectin (MBL) has an important role in first-line host defense against pathogens via the lectin pathway. We recently reported that functional MBL was significantly lower in CRF patients than in healthy subjects. In this study, we aimed to determine whether functional MBL would be improved following hemodialysis (HD) therapy. This study included 22 patients with end-stage renal disease (ESRD) on maintenance HD. Functional MBL was measured every 6 months for 1 year after HD using an enzyme-linked immunosorbent assay. Median serum functional MBL levels of ESRD patients were significantly higher after 6 and 12 months than at the start of HD therapy (p < 0.05 and p < 0.01, respectively). Furthermore, median functional MBL levels at 12 months were significantly higher than those at 6 months (p < 0.05). We found significant increases in serum functional MBL levels in patients on HD. Our results indicated that HD tailored to remove uremic toxins could improve functional MBL levels in these patients.
    Journal of Innate Immunity 02/2012; 4(3):293-300. · 4.46 Impact Factor
  • American Journal of Kidney Diseases - AMER J KIDNEY DIS. 01/2011; 57(4).
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    ABSTRACT: Mannose-binding lectin (MBL) plays an important role in first-line host defence against pathogens via the lectin pathway. The binding affinity for ligands is greatly increased by oligomerization, although the basic triplet does not bind solid phase mannan and cannot activate complement. Besides, MBL is a positive acute-phase protein. In this study, we examined the relationship between oligomer and functional serum MBL in chronic renal failure patients who were either uraemic [Pre-haemodialysis (pre-HD) patients], or who were receiving maintenance haemodialysis treatment (HD patients). This study included a total of 20 Pre-HD patients, 130 HD patients and 28 healthy subjects. The oligomer and functional serum MBL levels were measured using enzyme-linked immunosorbent assays established previously. The median serum functional MBL levels were significantly reduced in both Pre-HD and HD patients compared with healthy subjects (P<0·05 for both). Furthermore, the median functional MBL level in Pre-HD patients was significantly lower than that in HD patients (P<0·05). The median serum oligomer MBL levels in both Pre-HD and HD patients were significantly higher compared with healthy subjects (P<0·05 for both). Furthermore, the median oligomer MBL level in HD patients was significantly (P<0·05) higher than that in Pre-HD patients. The ratios of median serum functional MBL levels to oligomer MBL levels were significantly reduced in both Pre-HD and HD patients compared with healthy subjects (P<0·05 for both). We found significant reductions in the ratios of serum functional MBL levels to oligomer MBL levels in HD and Pre-HD patients compared with healthy subjects.
    European Journal of Clinical Investigation 10/2010; 40(10):865-73. · 3.37 Impact Factor
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    ABSTRACT: A patient on continuous cyclic peritoneal dialysis for chronic kidney disease due to type 2 diabetes mellitus developed peritoneal dialysis-associated peritonitis induced by Pasteurella multocida that was isolated from a sample of dialysis effluent. The route of infection was unknown for this case; however, P. multocida was also isolated from a culture of a pharyngeal swab obtained from the patient's cat. There was no evidence that the cat had bitten and ruptured the peritoneal dialysis tubing or bags. Pulsed-field gel electrophoresis (PFGE) showed that the P. multocida isolated from the patient was completely identical to the strain isolated from the domestic cat. As there is a rise in the pet-keeping population, an increase in zoonoses is to be expected. It is necessary to be carefully informed of hygiene rules in keeping pets because a pet may transmit zoonoses, even on casual contact.
    Therapeutic apheresis and dialysis: official peer-reviewed journal of the International Society for Apheresis, the Japanese Society for Apheresis, the Japanese Society for Dialysis Therapy 06/2010; 14(3):373-6. · 1.53 Impact Factor
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    ABSTRACT: The International Kidney Evaluation Association Japan evaluated chronic kidney disease (CKD) in Japan, using a Japanese version of the US National Kidney Foundation's Kidney Early Evaluation Program (KEEP). The screening criteria for the first 1065 participants were presence of diabetes or hypertension, or family history of diabetes, hypertension, or kidney disease. Mean age was 59.7+/-16.1 years; 501 participants were men, 564 women. Of participants, 26.9% had diabetes, 59.2% had hypertension (with an additional 21.5% diagnosed after the program), 16.9% had history of diabetes and hypertension together, and 30.6% had neither, but had family history of diabetes, hypertension, or kidney disease. CKD (stages 1-4) prevalence was 26.7%, defined by albumin-creatinine ratio and estimated glomerular filtration rate. CKD prevalence was 35.0% among diabetic participants, 34.8% among hypertensive participants, and 37.1% among participants with cardiovascular disease (CVD). The following baseline conditions were significantly associated with discovered CKD: diabetes, odds ratio 1.71 (95% confidence interval 1.28-2.30); hypertension, 3.42 (2.15-5.44); CVD, 1.88 (1.37-2.57). CKD prevalence was high compared with the general Japanese population. KEEP Japan seems to define a high-risk population with evidence of CKD based on the targeted nature of the program.
    Kidney international. Supplement 03/2010;
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    ABSTRACT: We had encountered a 74-year-old woman on hemodialysis therapy suffering from liver abscess of Actinomyces israelii. Percutaneous drainage of the abscess before starting antimicrobial therapy followed by correct microbiological identification and susceptibility test led us to determine long treatment with ampicillin and to a successful outcome. Periodontitis was thought to be a possible entry of actinomyces. Hepatic actinomycosis should be recognized as one of the important infectious diseases among patients of end-stage renal disease.
    Internal Medicine 01/2010; 49(18):2017-20. · 0.97 Impact Factor
  • American Journal of Kidney Diseases - AMER J KIDNEY DIS. 01/2010; 55(4).
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    ABSTRACT: We assessed the usefulness of reporting direct blood Gram stain results compared with the results of positive blood cultures in 482 episodes and monitored impact on selection of antimicrobial treatment. We found that the reporting groups "Staphylococcus spp," "Pseudomonas spp and related organisms," and "yeasts" identified in this way matched perfectly with later culture identification. When the report indicated Staphylococcus spp or Pseudomonas spp and related organisms, physicians started or changed antimicrobials suitable for these bacteria more frequently than when "other streptococci" and "family Enterobacteriaceae" were reported (P < .05). Incorrect recognition of Acinetobacter spp as Enterobacteriaceae family is still the most challenging problem in this context. Gram stain results that definitively identify Staphylococcus spp, Pseudomonas spp and related organisms, and yeasts reliably can be rapidly provided by clinical laboratories; this information has a significant impact on early selection of effective antimicrobials. Further investigation is needed to assess the clinical impact of reporting Gram stain results in bacteremia.
    American Journal of Clinical Pathology 07/2009; 132(1):18-25. · 2.88 Impact Factor
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    ABSTRACT: The MB fraction of creatine kinase (CK-MB) has long been used as a cardiac marker. It is known that the CK-MB immunoinhibition method lacks selectivity and accuracy, because the appearance of macro CK type 2, corresponding to mitochondrial creatine kinase (MtCK) in some patient serum may render CK-MB activity measured by conventional method abnormally high. Thus, to improve the specificity and accuracy of the CK-MB assay, we developed two types of monoclonal anti-MtCK antibodies against sarcomeric MtCK and ubiquitous MtCK, and present herein the performance of a new method using these antibodies. The performance of our test for detecting CK-MB activity was compared with other methods, and the range of CK-MB activities in normal human serum was investigated. The two types of monoclonal antibodies developed by us were isoenzyme-specific to sMtCK or uMtCK. The correlation coefficients of our method and conventional method to electrophoresis were 0.973 and 0.873, respectively. The mean CK-MB activity in normal human serum by our method and the conventional method was 2.4 and 11.7 U/L, respectively. Thus, our data indicated that about 80% of CK-MB activity, determined using the conventional method, seems to correspond to the MtCK activity. Our method is novel in offering higher accuracy of measuring true CK-MB contents in human serum as compared to the conventional method. The possibility of accurately estimating CK-MB activity by our method which can inhibit MtCKs in healthy person and patient serum is likely to bring a break-through in clinical diagnostics.
    Scandinavian journal of clinical and laboratory investigation 06/2009; 69(6):687-95. · 1.38 Impact Factor
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    ABSTRACT: Seasonal variations in laboratory test results have been pointed out in dialysis patients. Although the mechanism for this phenomenon is not clear, this could result in changes in dialysis and medication prescriptions. We investigated the effect of the circannual rhythm on laboratory test parameters in chronic haemodialysis patients. Data of 38 laboratory test parameters were collected every month and analyzed for 150 stable haemodialysis patients, with non-linear sine wave regression and paired t test between data of peak and trough months. Serum urea nitrogen, unsaturated iron binding capacity, lactate dehydrogenase, alkaline phosphatase, amylase, and neutrophil count showed significant circannual rhythms with high amplitudes. Additionally, serum creatinine, uric acid, chloride, calcium, phosphate, magnesium, total cholesterol, total protein, leucocyte count, mean corpuscular haemoglobin level, mean corpuscular haemoglobin concentration, and platelet count showed significant circannual rhythms with little amplitudes. The circannual rhythm of laboratory test parameters could be attributed to seasonal variations in food intake. Awareness of these variations should be taken into account in the interpretation of laboratory results.
    Blood Purification 02/2008; 26(2):196-203. · 2.06 Impact Factor
  • Mitsuru Yanai, Yuki Uehara, Kazunari Kumasaka
    Therapeutic apheresis and dialysis: official peer-reviewed journal of the International Society for Apheresis, the Japanese Society for Apheresis, the Japanese Society for Dialysis Therapy 02/2007; 11(1). · 1.53 Impact Factor
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    ABSTRACT: Blood culture has long been recognized as the gold standard for the definitive diagnosis of bacterial and fungal infections. However, fewer blood cultures have been tested and their results have not been fully used in Japan. Clinical laboratory physicians should play an interventional role, such as recommending blood culture tests in patients with infectious disease or fever of unknown origin. In our hospital, clinical laboratory physicians act as on-call consultants. The yearly number of consultations is between 500 and 700, and consultations concerning infectious disease have increased up to 40% in the past 5 years. As a result, the number of blood cultures and the percentage of 2-set blood collections have increased in order to increase the positivity rate and determine whether the results obtained were contaminated. However, physicians sometimes misunderstand the results of blood culture, and they assume that the identified organism was causative, or that sepsis did not exist if the culture is negative. Clinical laboratory physicians should act as consultants more frequently, concerning the interpretation of blood culture results, and the choice of antimicrobial agents, because the inappropriate use of antimicrobial agents leads to higher mortality and higher medical costs. Finally, collaboration between clinical laboratory physicians and co-medical staff such as the infection control team, nurses and pharmacists is necessary.
    Rinsho byori. The Japanese journal of clinical pathology 11/2006; 54(10):1059-65.
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    ABSTRACT: Patients receiving hemodialysis are generally considered to be at increased risk of developing tuberculosis. In the current study, in order to evaluate the usefulness of serological tests in dialysis patients, serum antibodies for tuberculous glycolipids antigen (TBGL) and for lipoarabinomannan (LAM) were measured in hemodialysis patients. The present study included 243 hemodialysis patients. Serum antibodies for TBGL and LAM were measured. Tuberculin skin tests were carried out and chest X-rays evaluated at the same time. There were no patients with active tuberculosis at the time of blood sampling. Thirty-six patients (14.8%) and 25 patients (10.3%) were positive for anti-TBGL antibody and anti-LAM antibody, respectively. One hundred and fifty-five patients (63.8%) were positive for tuberculin skin testing and 123 patients (50.6%) had old pulmonary tuberculosis on their chest X-ray. There was no significant correlation between the results of anti-TBGL antibody and anti-LAM antibody. There were no relationships among the results of tuberculin skin test and the two serological tests. However, positivity of anti-TBGL antibody and anti-LAM antibody was significantly higher in patients with findings of old tuberculosis on the chest X-ray than those without findings. The current results show that these serological tests are positive more frequently in hemodialysis patients without any proof of active tuberculosis than in healthy subjects (2%) and careful interpretation is necessary for relevant results.
    Therapeutic apheresis and dialysis: official peer-reviewed journal of the International Society for Apheresis, the Japanese Society for Apheresis, the Japanese Society for Dialysis Therapy 07/2006; 10(3):278-81. · 1.53 Impact Factor
  • Mitsuru Yanai, Yuki Uehara, Susumu Takahashi
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    ABSTRACT: As there is a high risk of indirect and direct transmission of infectious agents in chronic hemodialysis, infection control procedures should be established in dialysis units. This paper presents the findings of a questionnaire designed to survey the current status of infection control procedures in hemodialysis settings. Two hundred and forty-three hemodialysis units in Japan were surveyed. Nearly 90% of hemodialysis units reported compliance with each procedure recommended by the Center for Disease Control and Prevention in the United States, including use of disposable gloves, handling of non-disposable or non-single-use items, and routine serological testing of blood-borne viruses. However, more than 50% of units reported that they did not comply with recommendations concerning some procedures, such as places for preparing medications and their delivery, clean areas in the units, vaccination for hepatitis B, and additional measures for hepatitis B surface antigen (HBs-Ag) positive patients. Especially, the concept of universal precautions seemed to be misunderstood in units with a high prevalence of anti-hepatitis C antibody-positive (anti-HCV Ab-positive) patients. In conclusion, further intensive education and training will be necessary to establish infection control procedures.
    Therapeutic apheresis and dialysis: official peer-reviewed journal of the International Society for Apheresis, the Japanese Society for Apheresis, the Japanese Society for Dialysis Therapy 03/2006; 10(1):78-86. · 1.53 Impact Factor
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    ABSTRACT: ImmunoCard STAT! RSV (Meridian Bioscience, Inc, USA) is a rapid immunoassay method newly developed for detection of respiratory syncytial virus (RSV) by immunochromatography. We carried out an evaluation of the ImmunoCard STAT! RSV. One hundred fifty-nine nasal wash samples and nasopharyngeal aspirates from patients were used to evaluate three different kits, which are ImmunoCard STAT! RSV, RSV testpack (Abbott JAPAN) and Directigen EZ RSV (Nippon Becton, Dickinson and Company) . One hundred twenty-eight samples showed equivalent results. When nested reversed transcription-PCR (nested RT-PCR) results for 31 samples showing discrepancies among three kits, 10 samples were positive, and 21 samples were negative by nested RT-PCR. Compared to Nested RT-PCR results, ImmunoCard STAT! RSV showed a sensitivity of 90.5% (19/21) and a specificity of 80.0% (8/10), as well as RSV testpack showed a sensitivity of 10.0% (2/21) and a specificity of 100% (10/10), Directigen EZ RSV showed 95.2% (20/21) and 0.0% (0/ 10), respectively. Furthermore, the detection limits were also evaluated by using ACTT No. VR1540 for RSV A-2 strain, and ACTT No. VR1401 for Wash strain. The detection limit of ImmunoCard STAT! RSV was 5.15 x 10(6) TCID50/mL in subgroup A strain and was 7.58 x 10(5) TCID50/mL in subgroup B strain. This result was similar to RSV testpack, and was better than the detection limit of Directigen EZ RSV. It is concluded that ImmunoCard STAT! RSV is useful in detecting RSV in a clinical setting with equivalent performance to conventional other detecting kits.
    Kansenshogaku zasshi. The Journal of the Japanese Association for Infectious Diseases 05/2005; 79(4):276-83.
  • Mitsuru Yanai
    Nippon rinsho. Japanese journal of clinical medicine 12/2004; 62 Suppl 11:209-11.
  • Mitsuru Yanai
    Nippon rinsho. Japanese journal of clinical medicine 12/2004; 62 Suppl 11:227-9.