Search PubMed⌕ Search

Biomedical subjects

K Maekawa

Publications and source records attributed to K Maekawa.

At least 37 records · Page 2Linked to original sources

Impaired secretion of parathyroid hormone is coherent to diabetic hemodialyzed patients.

Diabetic bone disease is characterized by low bone turnover resulting from impaired secretion of parathyroid hormone (PTH). However, it was suggested that the difference in duration of hemodialysis (HD) therapy and age of patients between HD patients with and without diabetes mellitus (DM) may be responsible for a significant reduction in serum intact PTH (iPTH) level in HD patients with DM. The present study showed that although such major factors affecting PTH secretion as age, sex, HD duration, and serum calcium, phosphate, and magnesium levels did not differ significantly between HD patients with and without DM, serum iPTH levels were still significantly lower in HD patients with than without DM. Among biochemical markers for bone metabolism, serum levels of intact osteocalcin (iOC) and deoxypyridinoline (DPD) were significantly lower in HD patients with than without DM, whereas serum bone-specific alkaline phosphatase, pyridinoline, and beta-crosslaps did not differ significantly between the two groups of patients. In summary, our findings indicate that PTH secretion may be significantly impaired in HD patients with DM compared with those without DM, and serum iOC and DPD are bone markers sensitive enough to detect low bone turnover in HD patients with DM.

Aged↗

Changes in body fat mass in male hemodialysis patients: a comparison between diabetics and nondiabetics.

Nutritional status is an important factor that affects morbidity and mortality of hemodialysis patients. We investigated 1-year changes in body fat mass of male patients undergoing hemodialysis (duration, 4.9 +/- 2.5 years). Fat mass of 217 male patients (age 60 +/- 13 years) was measured by dual x-ray absorptiometry twice in a 1-year interval. The patients consisted of 70 with diabetes mellitus and 147 without diabetes. At the second measurement compared with the first, a significant decrease in fat mass was observed in diabetic patients (12.1 +/- 4.4 kg versus 11.0 +/- 4.7 kg; P < 0.01); there were no significant changes in fat mass in nondiabetic patients (12.2 +/- 5.0 kg versus 11.9 +/- 4.9 kg; P = 0.15). Significant differences in percent fat mass changes per year were seen between diabetic and nondiabetic patients (P < 0.05). Protein catabolic rates of diabetic patients were significantly lower than those of nondiabetic patients (0.86 +/- 0.18 g/kg/d versus 0.93 +/- 0.19 g/kg/d; P < 0.05). In all patients, there was a significant correlation between protein catabolic rates and percent fat mass changes per year (r = 0.15; P < 0.05). These results showed that body fat mass was decreased significantly in 1 year in male diabetic patients with maintenance hemodialysis, suggesting poorer nutritional status in these patients. Poor protein intake may be one of the risk factors for the decrease in fat mass. Dual x-ray absorptiometry assessment of fat mass changes is suggested as a useful method to examine clinically the nutritional status of hemodialysis patients.

Absorptiometry, Photon↗

Evaluation of posttreatment response of hepatocellular carcinoma with contrast-enhanced coded phase-inversion harmonic US: comparison with dynamic CT.

PURPOSE: To assess the reliability of contrast material-enhanced real-time gray-scale ultrasonography (US) in evaluating posttreatment response of hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Fifty HCC nodules were examined with contrast-enhanced coded phase-inversion harmonic US before and after treatment. Intratumoral vascularity was assessed with continuous imaging in the early arterial phase and with interval-delay scanning to depict tumor parenchymal flow during the blood pool phase. Vascular findings at US were compared with those at dynamic computed tomography (CT). RESULTS: In 50 HCC nodules before treatment, positive enhancement of tumor vessels and tumor parenchymal flow (stain) were observed in 47 (94%) and 46 (92%), respectively. Either tumor vessel or stain was visualized with coded harmonic US in 49 of 50 nodules. Eighty-one coded harmonic US studies were performed in 49 posttreatment HCC nodules. Compared with dynamic CT, the sensitivity, specificity, and accuracy of coded harmonic US in helping to detect positive enhancement in pretreatment HCC were 98% (49 of 50), 100% (50 of 50), and 98% (49 of 50), respectively. After treatment, positive enhancement of tumor vascularity was observed in 39 (48%) of 81 posttreatment studies, and no enhancement was observed in others (52%). Coded harmonic US demonstrated partial and no enhancement of tumor vascularity in four and one nodule, respectively; after transcatheter arterial embolization with iodized oil, evaluation of tumor vascularity with dynamic CT was difficult because of the presence of oil. CONCLUSION: With enhancement, coded harmonic US depicted tumor vascularity by showing tumor vessels in a real-time fashion at continuous imaging and tumor parenchymal flow at interval-delay scanning.

Adult↗

Hepatocellular carcinoma: depiction of tumor parenchymal flow with intermittent harmonic power Doppler US during the early arterial phase in dual-display mode.

PURPOSE: To assess the effectiveness of contrast material-enhanced intermittent harmonic Doppler ultrasonography (US) in depicting tumor vessels and tumor parenchymal flow (stain) in hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Fifty-eight patients with 65 HCC nodules were examined by using intermittent harmonic power Doppler US and digital subtraction harmonic B-mode US, both with intravenous administration of SH U 508A. Vascular findings at early arterial phase harmonic US were classified as positive enhancement or nonenhancement, depending on the tumor vascularity relative to the surrounding liver parenchyma. These results were compared with those of three-phase helical dynamic computed tomography (CT). RESULTS: For hypervascular HCCs, there was excellent depiction of tumor vessels and tumor stain with the two intermittent harmonic US methods. The sensitivity and specificity for depiction of tumor vascularity were 93% (41 of 44 nodules) and 100% (21 of 21), respectively, with intermittent harmonic power Doppler US and 86% (38 of 44) and 100% (21 of 21), respectively, with subtraction US, as compared with these values at dynamic CT. Attenuation was an important factor in the depictability of tumor vascularity at harmonic US. CONCLUSION: Contrast-enhanced intermittent harmonic US enables noninvasive demonstration of tumor vessels and especially tumor stain in HCC.

Adult↗

Randomized controlled evaluation of non-surgical treatments for temporomandibular joint anterior disk displacement without reduction.

The common methods for treating anterior disk displacement without reduction (ADDwor) are not based on randomized controlled clinical trials. Our study evaluated non-surgical treatments in 69 MRI-confirmed ADDwor subjects (m/f = 6/63). Subjects were randomly assigned to a control group and one of two treatment groups. Outcomes included maximum mouth opening, visual analogue scale of pain, and daily activity limitation. Calibrated examiners collected data at the initial interview and at 0, 2, 4, and 8 weeks of treatment. At the eight-week point, within-group improvements were present for all variables, for all groups. Between-group differences were not highly evident, with only mean daily activity limitation for the self-care/NSAID group being significantly lower than that of the occlusal appliance/jaw mobilization + self-care/NSAID group at the two- and four-week time-points. These results suggest that ADDwor subjects will improve with only minimal treatment intervention, and no significant difference was evident for the treatments tested and the control condition.

Activities of Daily Living↗

Initial symptoms of acute radiation syndrome in the JCO criticality accident in Tokai-mura.

A criticality accident occurred on September 30, 1999, at the uranium conversion plant in Tokai-mura (Tokai-village), Ibaraki Prefecture, Japan. When the criticality occurred, three workers saw a "blue-white glow," and a radiation monitor alarm was sounded. They were severely exposed to neutron and gamma-ray irradiation, and subsequently developed acute radiation syndrome (ARS). One worker reported vomiting within minutes and loss of consciousness for 10-20 seconds. This worker also had diarrhea an hour after the exposure. The other worker started to vomit almost an hour after the exposure. The three workers, including their supervisor, who had no symptoms at the time, were brought to the National Mito Hospital by ambulance. Because of the detection of gamma-rays from their body surface by preliminary surveys and decreased numbers of lymphocytes in peripheral blood, they were transferred to the National Institute of Radiological Sciences (NIRS), which has been designated as a hospital responsible for radiation emergencies. Dose estimations for the three workers were performed by prodromal symptoms, serial changes of lymphocyte numbers, chromosomal analysis, and 24Na activity. The results obtained from these methods were fairly consistent. Most of the data, such as the dose rate of radiation, its distribution, and the quality needed to evaluate the average dose, were not available when the decision for hematopoitic stem cell transplantation had to be made. Therefore, prodromal symptoms may be important in making decisions for therapeutic strategies, such as stem-cell transplantation in heavily exposed victims.

Amylases↗

Brief note and evaluation of acute-radiation syndrome and treatment of a Tokai-mura criticality accident patient.

Patient A who was exposed to a critical dose of radiation developed skin lesions throughout the body surface, gastrointestinal disorder with massive diarrhea and prominent bleeding, which caused severe loss in body fluids. Gastrointestinal bleeding due to the deteriorated intestinal mucosa was considered to be one of the major causes of death, although infection did not develop, possibly because of SDD and aseptic intensive care, until terminal stages. Patient A ultimately developed respiratory and renal failure in addition to skin exudate and gastrointestinal bleeding, and died of multiple organ failure on the 83rd day after exposure. The extreme unevenness of the dose distribution and the neutron versus y-ray component made the clinical manifestation very complicated. Initially, the mean absorbed dose was calculated as 16-20 GyEq for Patient A, mainly based on neutron-activated 24Na in the blood. However, a very recent calculation showed that the absorbed skin dose was highest at the upper-right abdomen reaching 61.8 Gy (27.0 as neutron plus 34.8 Gy as y-ray). The dorsal side was calculated to have received one eighth of the value of the abdominal side, and much smaller neutron component. His absorbed-dose distribution throughout the body was very inhomogeneous because of the closeness of the standing point to the mixing tank. Despite prolonged survival because of intensive care with massive fluids and blood transfusion, peripheral blood stem-cell transplantation, cultured skin-cell grafts, and the administration of cytokines for marrow, the patient was not saved. Restoration of the bone marrow function, prevention of skin fibrosis, radiation lung damage, and repair of gastrointestinal mucosa, and final recovery of the patient were elusive. Abundant personnel and resources were also a prerequisite to allow for the comprehensive and collective intensive care. A further understanding of the effects of high-dose radiation as well as the basic and clinical development of regeneration medicine are important issues for the future.

Adult↗

Effects of sarin on the nervous system in rescue team staff members and police officers 3 years after the Tokyo subway sarin attack.

Although the clinical manifestations of acute sarin poisoning have been reported in detail, no comprehensive study of the chronic physical and psychiatric effects of acute sarin poisoning has been carried out. To clarify the chronic effects of sarin on the nervous system, a cross-sectional epidemiologic study was conducted 3 years after the Tokyo subway sarin attack. Subjects consisted of the rescue team staff members and police officers who had worked at the disaster site. Subjects consisted of 56 male exposed subjects and 52 referent subjects matched for age and occupation. A neurobehavioral test, stabilometry, and measurement of vibration perception thresholds were performed, as well as psychometric tests to assess traumatic stress symptoms. The exposed group performed less well in the backward digit span test than the referent group in a dose-effect manner. This result was the same after controlling for possible confounding factors and was independent of traumatic stress symptoms. In other tests of memory function, except for the Benton visual retention test (mean correct answers), effects related to exposure were also suggested, although they were not statistically significant. In contrast, the dose-effect relationships observed in the neurobehavioral tests (psychomotor function) were unclear. None of the stabilometry and vibration perception threshold parameters had any relation to exposure. Our findings suggest the chronic decline of memory function 2 years and 10 months to 3 years and 9 months after exposure to sarin in the Tokyo subway attack, and further study is needed.

Adult↗

Contrast-enhanced subtraction harmonic sonography for evaluating treatment response in patients with hepatocellular carcinoma.

OBJECTIVE: Our objective was to assess the usefulness of contrast-enhanced subtraction harmonic sonography in evaluating the treatment response of patients with hepatocellular carcinoma. SUBJECTS AND METHODS: Thirty-two hepatocellular carcinoma lesions in 26 patients (age range, 44-85 years; mean age, 66 years) were examined with Levovist-enhanced intermittent harmonic imaging before and after therapy. A Toshiba Powervision 8000 was used. A subtraction image was obtained by digitally subtracting the last-frame harmonic image from the first-frame image when multishot mode was preset. Results of contrast-enhanced CT were compared with the results of subtraction harmonic imaging. RESULTS: Before therapy, an enhancement pattern of tumor vascularity was seen for 93.8% (30/32) of hepatocellular carcinoma nodules on subtraction harmonic imaging. After therapy, subtraction harmonic imaging showed 46.7% (14/30) enhancement (incomplete tumor necrosis) and 53.3% (16/30) no enhancement (complete tumor necrosis). When dynamic CT was the gold standard, the sensitivity, specificity, and accuracy of subtraction harmonic imaging were 93.3%, 100%, and 96.7%, respectively. Intratumoral flow signals in hepatocellular carcinoma after therapy on harmonic imaging were used as a guide to target additional percutaneous therapy. CONCLUSION: Digital subtraction contrast-enhanced harmonic imaging can depict tumor vascularity in hepatocellular carcinoma after therapy sensitively and accurately. Because it is easy to perform and provides real-time needle insertion guidance, it may be preferable to perform after localized therapy to monitor treatment response, which will reduce unnecessary CT scanning.

Aged↗

[Female carrier of Duchenne muscular dystrophy presenting with secondary dilated cardiomyopathy: a case report].

A 48-year-old female carrier of Duchenne muscular dystrophy had developed congestive heart failure but had no skeletal muscle symptoms. She was admitted to our hospital complaining of palpitation in December 1998. Her three sons had Duchenne muscular dystrophy. Neurological examination was unremarkable with no evidence of muscle weakness. Serum creatine kinase level was slightly increased. Echocardiography showed severe left ventricular dysfunction. Coronary angiography showed no abnormalities. Left ventriculography showed generalized hypokinesis and left ventricular ejection fraction was 28%. Dystrophin immunostaining of the skeletal muscle biopsy specimen showed a mosaic pattern. The dystrophin negative fibers were scattered among positive fibers. Cardiomyopathy is the only clinical manifestation of dystrophin gene mutation in carriers. Beta-blocker therapy(carvedilol 5 mg/day) was effective in this patient.

Cardiomyopathy, Dilated↗

[A case of lung cancer in which FDG-PET was useful for preoperative diagnosis].

The patient was 48-year-old woman. The patient was referred to our hospital due to detection of an abnormal shadow on a chest X-ray image during a health checkup. The results of a CT scan morphologically suggested a benign tumor, but a diagnosis could not be made even after bronchoscopic cytology. FDG-PET revealed accumulation at the tumor site suggestive of malignancy, and an operation was performed. Prompt pathological examination showed that the tumor was adenocarcinoma, and right lower lobectomy and lymphnode dissection were performed. FDG-PET is thought to be useful for diagnosis in cases of lung tumor in which a preoperative diagnosis can not be established.

Adenocarcinoma↗

[Ergocalciferol Reference Standard (Control 001) of National Institute of Health Sciences].

The raw material of ergocalciferol was examined for the preparation of "Ergocalciferol Reference Standard (Control 001)". Analytical data obtained were: melting point, 114.8 degrees C; UV and infrared spectra, the same as those of JP Ergocalciferol Reference Standard (Control 971); specific absorbance, E1ca1% = 471(265 nm); optical rotation, [alpha]D20 = +102.4 degrees; thin-layer chromatography, no impurities were detected until 100 micrograms; high-performance liquid chromatography (HPLC), total amount of impurities estimated to be less than 0.1%. Based on the above results, the raw material was authorized as the Japanese Pharmacopoeia Ergocalciferol Reference Standard (Control 001).

Chemical Phenomena↗

[Alprostadil Reference Standard (Control 001) of National Institute of Health Sciences].

The raw material of Alprostadil was examined for the preparation of "Alprostadil Reference Standard (Control 001)". Analytical data obtained were: IR spectrum, same as that of the Alprostadil Reference Standard (Control 923); thin-layer chromatography, no impurities were detected until 20 micrograms; high-performance liquid chromatography (HPLC), total amount of impurities estimated to be less than 0.2%. Based on the above results, the raw material was authorized as the Japanese Pharmacopoeia Alprostadil Reference Standard (Control 001).

Alprostadil↗

[Cholecalciferol Reference Standard (Control 001) of National Institute of Health Sciences].

The raw material of cholecalciferol was examined for the preparation of "Cholecalciferol Reference Standard (Control 001)". Analytical data obtained were: melting point, 83.2 degrees C; UV and infrared spectra, the same as those of JP Cholecalciferol Reference Standard (Control 971), respectively; specific absorbance at 265 nm, E1ca1% = 478; optical rotation, [alpha]D20 = +108.6 degrees; thin-layer chromatography, no impurities were detected until 100 micrograms; high-performance liquid chromatography (HPLC), total amount of impurities estimated to be less than 0.05%. Based on the above results, the raw material was authorized as the Japanese Pharmacopoeia Cholecalciferol Reference Standard (Control 001).

Chemical Phenomena↗

[Betamethasone Sodium Phosphate Reference Standard (Control 001) of National Institute of Health Sciences].

The raw material of betamethasone sodium phosphate was examined for the preparation of the "Betamethasone Sodium Phosphate Reference Standard (Control 001)". The analytical data obtained were: melting point, 207.2 degrees C; pH, 8.1; optical rotation, [alpha]D20 = +104.4 degrees; UV spectrum, lambda max of 242 nm and specific absorbance in water at 242 nm = 272.9; IR spectrum, specific absorptions at 3386.9, 1721.7, 1663.3, 1620.4, 1605.0, 1094.3, 985.8, 889.8 cm-1; free phosphoric acid, 0.3%; thin-layer chromatography, one impurity was detected until 200 micrograms; high-performance liquid chromatography, total amount of impurities estimated to be less than 0.5%; water, 9.2%. Based on the above results, the raw material was authorized as the Betamethasone Sodium Phosphate Reference Standard (Control 001) of the National Institute of Health Sciences.

Betamethasone↗

[Hydrocortisone Sodium Phosphate Reference Standard (Control 001) of National Institute of Health Sciences].

The raw material of hydrocortisone sodium phosphate was examined for the preparation of the "Hydrocortisone Sodium Phosphate Reference Standard (Control 001)". The analytical data obtained were: pH, 8.3: optical rotation, [alpha]D20 = +126.2 degrees; UV spectrum, lambda max of 248 nm and specific absorbance in water at 248 nm = 338.6; IR spectrum, same as that of the Hydrocortisone Sodium Phosphate Reference Standard (Control 891); free phosphoric acid, 0.2%; free hydrocortisone, 0.01%; thin-layer chromatography, no impurity was detected until 200 micrograms; high-performance liquid chromatography, total amount of impurities estimated to be less than 0.2%; residual solvent, 0.0% (acetone) and 0.02% (ethanol); loss on drying, 1.5%. Based on the above results, the raw material was authorized as the Hydrocortisone Sodium Phosphate Reference Standard (Control 001) of the National Institute of Health Sciences.

Chromatography, High Pressure Liquid↗

[Beclometasone Dipropionate Reference Standard (Control 011) of National Institute of Health Sciences].

The raw material of beclometasone dipropionate was examined for the preparation of the "Beclometasone Dipropionate Reference Standard (Control 011)". The analytical data obtained were: melting point, 208.8 degrees C; optical rotation, [alpha]D20 = +91.7 degrees; IR spectrum, same as that of the Beclometasone Dipropionate Reference Standard (Control 865); thin-layer chromatography, one impurity was detected until 40 micrograms; high-performance liquid chromatography, total amount of impurities estimated to be less than 0.5%; loss on drying, 0.6%. Based on the above results, the raw material was authorized as the Beclometasone Dipropionate Reference Standard (Control 011) of the National Institute of Health Sciences.

Beclomethasone↗

[Dexamethasone Sodium Phosphate Reference Standard (Control 001) of National Institute of Health Sciences].

The raw material for dexamethasone sodium phosphate was examined for the preparation of the "Dexamethasone Sodium Phosphate Reference Standard (Control 001)". The analytical data obtained were: pH, 8.0; optical rotation, [alpha]D20 = +79.6 degrees; UV spectrum, lambda max of 242 nm and specific absorbance in water at 242 nm = 313.6; IR spectrum, same as that of the Dexamethasone Sodium Phosphate Reference Standard (Control 893); free phosphoric acid, 0.06%; free dexamethasone, 0.07%; thin-layer chromatography, no impurities were detected until 100 micrograms; high-performance liquid chromatography, total amount of impurities estimated to be less than 0.2%; residual solvent, 4.3% (ethanol); water, 7.3%. Based on the above results, the raw material was authorized as the Dexamethasone Sodium Phosphate Reference Standard (Control 001) of the National Institute of Health Sciences.

Chromatography, High Pressure Liquid↗