Biomedical subjects

K Nakane

Publications and source records attributed to K Nakane.

At least 19 recordsLinked to original sources

PubMed2002

Variation in CO2 assimilation rate induced by simulated dew waters with different sources of hydroxyl radical (*OH) on the needle surfaces of Japanese red pine (Pinus densifora Sieb. et Zucc.).

The hydroxyl radical (*OH) is generated in polluted dew on the needle surfaces of Japanese red pine (Pinus densiflora Sieb. et Zucc.). This free radical, which is a potent oxidant, is assumed to be a cause of ecophysiological disorders of declining trees on the urban-facing side of Mt. Gokurakuji, western Japan. Mists of *OH-generating N(III) (HNO2 and NO2-) and HOOH + Fe + oxalate solutions (50 and 100 microM, pH 5.1-5.4) simulating the dew water were applied to the foliage of pine seedlings grown in open-top chambers in the early morning. Needles treated with 100 microM N(III) tended to have a greater maximum CO2 assimilation rate (Amax), a greater stomatal conductance (g(s)) and a greater needle nitrogen content (Nneedle), suggesting that N(III) mist acts as a fertilizer rather than as a phytotoxin. On the other hand, needles treated with 100 microM HOOH + Fe + oxalate solution showed the smallest Amax, g(s), and Nneedle, suggesting that the combination of HOOH + Fe + oxalate caused a decrease in needle productivity. The effects of HOOH + Fe + oxalate mist on pine needles were very similar to the symptoms of declining trees at Mt. Gokurakuji.

Carbon Dioxide↗

PubMed2001

Measurement of ethylene emission from Japanese red pine (Pinus densiflora) under field conditions in NOx-polluted areas.

Emission of ethylene from the needles of Japanese red pine, Pinus densiflora, was measured in air-polluted areas in Hiroshima, Japan. We applied a suitable protocol to determine the rate of ethylene emission from the excised needles. The influence of excision of needles on ethylene emission was not detected during the first 4 h of incubation at 20 degrees C. Ethylene emissions were low in the unpolluted (clean) areas regardless of the altitude or season. The emission of stress ethylene increased with the atmospheric NO2 concentration, suggesting that atmospheric NOx or related substances induced the higher ethylene emission in the polluted areas (near urban and industrial areas). In all cases, 1-year-old needles emitted significantly larger amounts of ethylene than the current needles. Ethylene emission did not increase evenly in the polluted areas, but the frequency of trees emitting high ethylene increased. Therefore, threshold rates for the baseline ethylene emission were proposed.

Air Pollutants↗

PubMed2001

Clinical significance of TT virus in chronic hepatitis C.

BACKGROUND AND AIMS: Much is still unknown about the clinical significance of TT virus (TTV), which has been reported as a candidate for non A-G hepatitis virus. The aim of this study was to clarify the clinical significance of TTV in patients coinfected with TTV and hepatitis C virus (HCV). METHODS: The 95 subjects studied had chronic hepatitis C (CHC), and underwent interferon (IFN) therapy. TT Virus DNA was detected by using polymerase chain reaction. The nucleotide sequences were determined by using a dideoxy chain termination method. A phylogenetic tree was drawn up by using the neighbor-joining method. RESULTS: TT Virus DNA was detected in 37.9% of patients with the use of an open reading frame 1 (ORF1) primer, and in 88.4% of patients by using a 5' untranslated region (5' UTR) primer. Using both sets of primers, no differences were found between TTV-DNA-positive and -negative subjects with CHC in the clinical findings. Serum TTV DNA was eradicated in 30.6% of patients with the ORF1 primer, and in 19.1% of patients with the 5' UTR primer at 6 months after the cessation of IFN therapy. The levels of TTV DNA before IFN therapy were significantly lower in the viral eradication group than in non-eradication group. The changes in alanine aminotransferase (ALT) concentrations were significantly correlated with changes in HCV-RNA in CHC patients with TTV. Moreover, there was no correlation between the changes in TTV DNA and the course of ALT. CONCLUSION: Hepatocellular injury in patients with chronic hepatitis who are coinfected with HCV and TTV appears to primarily be caused by HCV and is less attributable to TTV.

Adult↗

PubMed2000

Iatrogenic GB virus C/hepatitis G virus infection in an area endemic for hepatitis C virus.

GB virus C/hepatitis G virus (GBV-C/HGV) is reported to be transmitted by blood products. This study reports infection with GBV-C/HGV from Area-O of town T, an area of high prevalence of antibody to hepatitis C virus (anti-HCV). Four hundred and thirty-five inhabitants of Area-O in town T were examined. Three hundred and forty-three inhabitants of Area-H in town T (where differences of age or sex are not markedly different to Area-O) were studied as controls. We investigated the virus markers and conducted a survey of life history in both areas. The seroprevalence of anti-HCV and GBV-C/HGV markers in Area-O was 17.7% and 11.7%, significantly higher than in Area-H (1.5% and 4.4%). The prevalence of GBV-C/HGV markers was significantly higher in the anti-HCV-positive group than in the sero-negative group. Anti-HCV- or GBV-C/HGV positive subjects tended to have a history of intravenous medications at hospital C in town T, suggesting iatrogenic infection through insufficient sterilization of needles and/or syringes.

Adult↗

PubMed1999

GB virus C infection: clinical significance.

GB virus C (GBV-C) RNA positivity rates were examined in serum specimens from 231 patients with liver disease (23 patients with hepatitis B, 175 patients with hepatitis C, five patients with hepatitis B virus plus hepatitis C virus coinfection, and 28 patients with non-A, non-B, non-C hepatitis) to clarify the clinical significance of this virus. GBV-C RNA was detected in none of 12 patients with fulminant hepatitis, one of two patients with acute hepatitis positive for hepatitis B surface antigen and one of four patients with acute non-A, non-B, non-C hepatitis. Pathogenetic involvement of GBV-C was suspected in some patients in the latter group. Among patients with the non-B, non-C type of chronic disease, one of seven with cirrhosis (14%) and none with chronic hepatitis or hepatocellular carcinoma were GBV-C-positive. In chronic hepatitis C patients who had received interferon treatment, no difference was found in clinical findings, alanine aminotransferase (ALT) concentrations, histology or response to interferon between 11 patients who were GBV-C RNA-positive and 101 patients who were GBV-C RNA-negative. Moreover, changes in ALT after interferon therapy showed no relation to positivity for GBV-C RNA. On the basis of these findings, GBV-C appears to be an unlikely cause of initiation or progression of chronic hepatic diseases.

Adult↗

PubMed1999

Primary biliary cirrhosis associated with membranous glomerulonephritis.

A 33-year-old woman was admitted to our department for evaluation of liver dysfunction and proteinuria. A liver biopsy specimen showed ductular proliferation and moderate portal fibrosis indicating stage II primary biliary cirrhosis. A renal biopsy specimen showed mild to moderate mesangial cell proliferation without crescent formation or interstitial nephritis. Immunofluorescent staining revealed deposition of immunoglobulin G (IgG), third component of complement (C3), and Clq on glomerular basement membranes. The findings indicated stage I membranous glomerulonephritis. Administration of ursodesoxycholic acid together with prednisolone, azathioprine, and dipyridamole decreased proteinuria and improved cholestatic liver dysfunction.

Adult↗

PubMed1998

Giant hepatic biloma following transcatheter oily chemoembolization in a patient with hepatic metastases from malignant pheochromocytoma.

A 48-year-old woman developed hepatic metastases from malignant pheochromocytoma resected 8 years previously. Angiography revealed multiple tumor stains in the liver. Transcatheter oily chemoembolization using styrenomaleic acid neocarzinostatin and iodized oil was performed. The patient complained of severe right upper quadrant pain immediately following the transcatheter oily chemoembolization. Necrotizing cholecystitis developed on the 4th day post-transcatheter oily chemoembolization, hepatic infarction on the 12th day, and a biloma on the 19th day. Despite the administration of antibiotics and percutaneous transhepatic drainage, neither the volume of drainage nor the size of the biloma decreased. Biliary reconstruction was performed using a metallic stent, which decreased the size of the biloma.

Adrenal Gland Neoplasms↗

PubMed1997

Kinetic assay of serum and urine for urea with use of urease and leucine dehydrogenase.

We describe a new kinetic assay for determining urea in serum or urine with use of urease (EC 3.5.1.5) and leucine dehydrogenase (EC 1.4.1.9). The latter enzyme is suitable for the kinetic assay of NH4+ because its Km value for NH4+ at pH 8.75 is large (approximately 500 mmol/L). Interference from endogenous NH4+ in serum or urine is obviated by subtraction of the assayed endogenous NH4+ value in a sample blank. For serum, within-assay CVs (n = 10) were 0.39-0.58%; day-to-day CVs (n = 10) were 1.56-2.30%. In urine, within-assay CVs (n = 10) were 0.86-1.15%. Analytical recovery of urea (0.893-71.4 mmol/L) added to patients' sera (urea 6.14 mmol/L) was 99.2-105.2%. The calibration curve for serum was linear through zero for urea concentrations up to 142.9 mmol/L and for urine up to 714.3 mmol/L. No influences of added ammonium ion, bilirubin, hemoglobin, ascorbic acid, or Intralipid were observed. The regression equations for this method (y) and conventional methods (x = Determiner-LUN for serum assays, Serotec UUR-R for urine) were: y = 1.016x - 0.12 mmol/L (r = 0.999, S(y/x) = 0.34 mmol/L, n = 100) for sera, and y = 1.070x - 12.6 mmol/L (r = 0.998, S(y/x) = 7.41 mmol/L, n = 100) for urine.

Amino Acid Oxidoreductases↗

PubMed1996

[A case of sarcoidosis with cranial mononeuritis multiplex and peripheral polyneuropathy].

A 67-year-old woman with sarcoidosis, cranial mononeuritis multiplex and peripheral neuropathy was reported. The initial presentation of her sarcoidosis was a subcutaneous nodule of left knee joint on June, 1990. The number of subcutaneous nodules increased. Sarcoidosis was diagnosed by biopsy of the subcutaneous nodule. Paresthesia of the face and limbs appeared from November, 1991 and one month later, left abducens palsy and hearing disturbances were added. Alternate day therapy of 20mg prednisolone was effective in improvement of symptoms. The case of sarcoidosis with cranial mononeuritis multiplex and peripheral polyneuropathy was rarely found in 6 to 25% of patients with sarcoid neuropathy in the previous reports. Angiotensin-converting enzyme (ACE) in cerebro-spinal fluid not only raised on exacerbation also lowered with improvement of symptoms after steroid therapy. The ACE, which had a selective activity in the central nervous system, seemed to contribute to the index of treatment for sarcoidosis.

Aged↗

PubMed1995

Relationship between susceptibility to apoptosis and Fas expression in peripheral blood T cells from uremic patients: a possible mechanism for lymphopenia in chronic renal failure.

Chronic renal failure (CRF) is often complicated by lymphopenia, which may be partly responsible for immune deficiency. We hypothesized that lymphopenia in CRF might result from apoptosis of T cells in vivo. To elucidate the involvement of Fas antigen which mediates apoptosis, we analyzed Fas expression on peripheral blood T cells in uremic non-dialyzed (non-HD) patients and hemodialysis (HD) patients. T cells from both uremic groups expressed Fas with higher intensity than control T cells. When two uremic groups were compared, Fas intensity on T cells was significantly higher in non-HD patients than in patients on HD. Moreover, uremic T cells were shown to undergo accelerated apoptosis when cultured in vitro, in correlation with Fas expression. Our results suggest that T cells in CRF may undergo apoptosis by the Fas system and that hemodialysis treatment has beneficial effects in the light of the inhibition of T cell apoptosis.

Apoptosis↗

PubMed1994

Evaluation of regional cerebral blood flow changes on perifocal brain tissue SPECT before and after removal of arteriovenous malformations.

In fifteen cases of arteriovenous malformation (AVM), serial examinations of regional cerebral blood flow (rCBF) using single photon emission computed tomography (SPECT) and N-isopropyl-(123I)p-iodoamphetamine were performed. On SPECT images, the nidus was visualized as a focal rCBF defect in all cases preoperatively and seven of these cases had abnormal decreased perfusion areas in the tissues adjacent to the nidus. In five cases, the postoperative SPECT images on the day after surgery revealed an abnormal increased perfusion area adjacent to the nidus and in one case the increased perfusion was accompanied by a massive intracerebral haemorrhage detected by brain computed tomography (CT). In seven cases, postoperative SPECT images showed widespread abnormal decreased perfusion areas in the surrounding tissues and brain CT revealed either intracerebral haemorrhage or significant cerebral oedema. In the other three cases, no remarkable rCBF changes were found in comparison with the pre-operative study. There was a tendency for the preoperative abnormal decreased perfusion area adjacent to the nidus to correlate with the postoperative hyperperfusion and for the postoperative abnormal decreased perfusion area to reflect brain damage.

Adolescent↗

PubMed1994

Determination of Kt/V and protein catabolic rate using pre- and postdialysis blood urea nitrogen concentrations.

We developed a new urea kinetic method for simultaneous determination of the Kt/V and protein catabolic rate (PCR) only from blood urea nitrogen (BUN) concentrations before and after a single dialysis session. Using this method, the parameters were calculated within 1.5 s even when a hand-held computer with a low central processing capacity is used. The total amount of urea eliminated during three dialysis sessions in 1 week is assumed to be equal to urea volume (Gw) generated over a 1-week period (Tw): [formula: see text]. Here, G is the generation rate, K is the dialyzer urea clearance, T is the dialysis time and C1, C2 and C3 are BUN during the respective dialysis session. If this equation and the equation expressing the urea kinetics during a single dialysis session are solved together, we have a solution for Kt/V and G. The thus-obtained Kt/V and G are corrected using the change in body weight. The corrected Kt/V showed a good correspondence with the parameter calculated with the classical method, and the midweek PCR derived from G determined by the present method being equivalent to the PCR averaged for a 1-week period determined by the classical methods.

Blood Urea Nitrogen↗

PubMed1994

[Early detection of hepatocellular carcinoma with lectin reactive alpha-fetoprotein].

Lens culimaris agglutinin A-reactive alpha-fetoprotein (AFP L3) and erythroagglutinating phytohemagglutin-reactive alpha-fetoprotein (AFP P4 + P5) were determined by a sensitive method using lectin-affinity electrophoresis coupled with antibody-affinity blotting, and the usefulness of this method for early detection of hepatocellular carcinoma (HCC) was examined. For 72 operated cases of the HCC group including 28 cases of small liver cancer, the AFP value was 124 +/- 198ng/ml (Mean +/- SD); the lectin fraction values for L3 and P4 + P5 were 12.2 +/- 17.9 and 17.9 +/- 17.9%, respectively, which were significantly higher compared with the chronic hepatitis (CH).cirrhosis (LC) group and showed an increasing tendency with an increase in tumor diameter. The cut-off values for distinguishing HCC from CH.LC, determined with the receiver-operating characteristic (ROC) plots, were 10.0 and 15.0% for the L3 and P4 + P5 fractions, respectively, and the positive rates in the patient with HCC were 33.3 and 48.6% for AFP L3 and AFP P4 + P5, respectively, and 59.7% with a combination assay. For small liver cancer, the positive rate was 17.9% with protein induced by vitamin K absence-II (PIVKA-II) and 46.4% with combination assay of AFP L3 and AFP P4 + P5. Also, for HCC below AFP 50ng/ml, a positive rate of 45.0% was obtained. In the CH.LC group, all cases were negative for AFP L3 and 2 of 44 cases (4.5%) were false-positive for AFP P4 + P5.

Carcinoma, Hepatocellular↗

PubMed1993

[Myocardial metabolism during dynamic exercise].

The development of Webster catheterization has enabled us to make clinical measurement of coronary sinus blood flow and to estimate the kinetics in myocardial substrate uptake. In this study, exercise tolerance test using supine multistage bicycle ergometer test was performed and exercise-induced hemodynamic alteration was evaluated in 18 patients with ischemic heart disease (16 males and 2 females, average age 56.3 years). The change in substrate kinetics in myocardial metabolism was also examined in terms of two indexes; myocardial uptake rate and myocardial uptake. The following results were obtained. 1) The myocardial uptake rates of glutamate and free fatty acid were significantly decreased by exercise, while those of glucose and lactate showed no significant change. 2) The myocardial uptakes of glutamate, glucose and lactate were significantly increased by exercise, but that of free fatty acid did not change significantly. 3) A significant negative correlation (r = -0.52, p < 0.05) was observed between the change in myocardial glutamate uptake and the change in pulmonary artery wedge pressure induced by exercise, suggesting that patients with ischemic heart disease might fail in glutamate uptake induced by exercise. The difference in the kinetics of myocardial uptake rate and myocardial uptake for glutamate, alanine, glucose, free fatty acid and lactate is observed. This difference occurs from the decrease in uptake rate due to the increase in coronary sinus blood flow. Myocardial uptake, which directly reflects myocardial energy metabolism is regarded as a more useful index of myocardial metabolism than myocardial uptake rate.

Energy Metabolism↗

PubMed1993

[The administered activity of radionuclides in nuclear medicine--rational reduction of medical radiation exposure].

A survey of 104 hospitals was conducted to determine the administered activity of radionuclides. Eighty-five hospitals responded, and reported a total of 119,614 examinations in one year. The examinations included: bone scintigraphy, 26.4%; Thallium-201 (201Tl) myocardial scintigraphy, 15.5%; Gallium-67 (67Ga) scintigraphy, 13.3%; N-isopropyl-p-[123I]iodoamphetamine (IMP) brain perfusion scintigraphy, 7.0%. The administered activity was corrected by body weight only for children at more than 80% of the responding hospitals. The number of hospitals that reported over-administration of radionuclide varied according to the type of scintigraphy performed: bone, 76%; inflammatory (67Ga), 93%; myocardial (201Tl), 89.2%; brain (IMP), 8.5%. The administered activity of IMP was closer to the upper limits specified in the Recommendations on Standardization of Radionuclide Imaging by the Japan Radioisotope Association (1987), because IMP is very expensive and is supplied as single vials. The highest average effective dose was for myocardial scintigraphy, the second-highest for inflammatory scintigraphy, and the third-highest for bone scintigraphy. In 201Tl and 67Ga scintigraphy, the entire contents of the vial may be administered two days before the expiration date, because the ratio of (true patient administered activity) to (declared patient administered activity) is similar to the ratio of (radioactivity on the day of supply) to (radioactivity on the day of expiration). The factors that influence administered activity are throughput, price of the radionuclide, and whether the radionuclide is sold as a single vial. In order to decrease the effective dose, it is necessary to establish a close cooperation between medical personnel, the makers of radiopharmaceuticals, and manufacturers of gammacameras.

Humans↗

PubMed1992

[In vivo effects on human neutrophils by administration of rhG-CSF and clinical significance].

To evaluate the clinical effect by administration of recombinant human granulocyte-stimulating factor (rhG-CSF) post chemotherapy in non-Hodgkin malignant lymphoma (NHL), 17 patients with NHL were subjected to this study. Administration of rhG-CSF ameliorated the decrease in absolute neutrophil counts after the cytotoxic chemotherapies and activated neutrophil functions in active oxygen product and expressions of adhesion proteins. To consistent with these results, rhG-CSF administrations post cytotoxic chemotherapy were effective for reducing infection complications associated with neutropenia. Furthermore, administration of rhG-CSF increased peripheral hematopoietic progenitor cells, thus suggesting promising therapeutic potential for autografting. Recently, it has been reported that blood neutrophils may synthesize mRNA and proteins important in inflammation including various cytokines such as IL-1, IL-6, TNF-alpha and IFN-alpha, but, administration of rhG-CSF showed no obvious effect on the level of either IL-1, IL-6, TNF-alpha or IFN-alpha in sera, and furthermore, the in vitro stimulation by rhG-CSF induced no significant production of these cytokines and expressions of TNF-alpha and IFN-alpha mRNAs. Finally, we studied on anti-tumor effect of administration of rhG-CSF in CDF1 mice inoculated with syngeneic lymphoma cells. rhG-CSF infusion suppressed the liver metastasis and prolonged the overall survival, thus suggesting the hypothesis that use of rhG-CSF in some patients with NHL might control the disease through stimulating both production and functional activation of neutrophils.

Aged↗

PubMed1992

Quantitative measurement of regional cerebral blood flow using N-isopropyl-(iodine-123)p-iodoamphetamine and single-photon emission computed tomography.

We have developed a quantitative method of measuring regional cerebral blood flow (rCBF) by using N-isopropyl-(iodine-123)p-iodoamphetamine and single-photon emission computed tomography (SPECT). Twenty-five dynamic SPECT images (24 sec/scan) were collected immediately after tracer injection using a ring-type SPECT system and the accumulation curve (C(t)) was obtained. The time-activity curve corresponding to the arterial blood activity curve was used as B(t). The latter curve was calculated from the lung time-activity curve monitored during scanning and corrected by the actual activity obtained by one-point blood sampling 5 min after tracer injection. The octanol extraction ratio during scanning was considered to be constant and taken as the value measured 5 min after tracer injection (E). The uptake constant (K) per pixel was calculated by the least squares fitting method as the slope of the linear relationship in which C(t)/E x B(t) was plotted against E x integral of t(o)B(tau)d tau/E x B(t). Functional maps of rCBF values were obtained on a 64 x 64 matrix by calculating the uptake constant per pixel and the cross calibration factor (CF) between the SPECT system and a well counter (rCBF = K.CF x 100).

Adult↗

PubMed1992

[Utilization of an enzyme-sensor in clinical medicine].

The utilization and merit of an enzyme-sensor for measuring serum- or urine-components were reported. The enzyme sensor (enzyme-electrode) is an H2O2-electrode, O2-electrode or ion selective electrode connected with an enzyme-immobilized nylon tube. First, the principle of measurements with an enzyme sensor was reported. Secondly, and H2O2 electrode which had been planned and developed in our laboratory was introduced. The outline of our apparatus and the procedure of enzyme-immobilization onto a nylon tube wall were explained. Then the results obtained from quantitative analysis of serum- and urine-components were shown. For the analysis by our apparatus, 3-60 microliters of serum or urine was used and incubation time was approximately 5 min. The results obtained by our apparatus coincided with those obtained by other methods (r = 0.981-0.997). Thirdly, the usefulness of commercial instruments with an enzyme-sensor for determining glucose- or lactic acid-content was described. The results (glucose and lactic acid-contents) measured by desktop-size instruments showed a high lineality and good reproducibility (CV = 0.6-1.5% in glucose and 0-0.7% in lactic acid). A good correlation was observed among each instrument (r = 0.999). The results by card-size instruments, GLUTEST E or ExacTech, showed a lower reproducibility (CV = 4.1-6.5%) and correlation (r = 0.95-0.98) than those by desktop-size instruments.

Biosensing Techniques↗