Biomedical subjects

N Furuta

Publications and source records attributed to N Furuta.

At least 19 recordsLinked to original sources

PubMed2006

Morphological features of cartilage observed during mandibular distraction in rabbits.

Ossification during distraction osteogenesis can be classified as intramembranous or endochondral. It is not known whether cartilage in the distraction gap is transformed into new bone. The aim of this study was to investigate the morphological features of ossification in the transition of cartilage to bone during mandibular distraction osteogenesis in a rabbit model. A cortical osteotomy was performed and custom-made devices were applied. Immediately after surgery, the devices were lengthened by 0.25 mm every 12h for up 10 days, during which time four rabbits were killed at 0, 5 and 10 days and examined using histological staining and immunohistochemical methods. Apoptotic cells were identified by an in-situ detection assay for nuclear DNA fragmentation using a modified TUNEL procedure, with several sections analyzed using software for histomorphometric analysis. The results showed that the amount of cartilage in the distraction gap was significantly decreased. The cartilage had ossified in two ways, termed endochondral ossification and transchondroid bone formation.

Alkaline Phosphatase↗

PubMed2006

A simple method for bone positioning of mandibular segments.

A simple bone-positioning technique is reported, using a combination of bone plates and a flexible tube filled with acrylic polymer. The flexible tube is solidified by injection of acrylic monomer. This technique is applicable for bone positioning after mandibular resection as well as positioning of the proximal segment after sagittal split ramus osteotomy. This technique has the advantages of greater simplicity and flexibility compared to previously reported methods of bone positioning.

Acrylic Resins↗

PubMed2001

Application of high-surface-area ZrO2 in preconcentration and determination of 18 elements by on-line flow injection with inductively coupled plasma atomic emission spectrometry.

A flow-injection analysis (FIA) system incorporating a micro-column of ZrO2 has been used for the development of an on-line multi-element method for the simultaneous preconcentration and determination of Al, Bi, Cd, Co, Cr, Cu, Fe, Ga, In, Mn, Mo, Ni, Pb, Tl, V, Sb, Sn, and Zn by inductively coupled plasma atomic emission spectrometry (ICP-AES). The conditions for quantitative and reproducible preconcentration, elution, and subsequent on-line ICP-AES determination were established. A sample (pH 8) is pumped through the column at 3 mL min(-1) and sequentially eluted directly into the ICP-AES with 3 mol L(-1) HNO3. With a sample volume of 100 mL and an elution volume of 1 mL signal enhancement 100 times better than for conventional continuous aspirating systems was obtained for the elements studied. The reproducibility (RSD %) of the method at the 10 ng mL(-1) level in the eluate is acceptable - less than 8% for five replicates. Recoveries between 95.4% and 99.9% were obtained for the elements analysed. ZrO2, with a specific surface area of 57 m2 g(-1) and a capacity of approximately 5 mg g(-1) for the elements studied, was synthesized by hydrolysis of ZrCl4. The preconcentration system was evaluated for several simple synthetic matrices, standard water samples and synthetic seawater. The effect of foreign ions on the efficiency of preconcentration of the elements studied was investigated. The application of a micro-column filled with high-surface-area ZrO2 and flow injection inductively coupled plasma atomic emission spectrometry enables preconcentration and simultaneous determination of 18 elements at low concentrations (ng L(-1)) in different water samples.

Chlorides↗

PubMed2001

[Pulmonary infarction caused by the spontaneous migration of the vena caval tumor thrombus of right renal cell carcinoma: a case report].

A 70-year-old male with right renal mass incidentally found by annual check-up using ultrasound, was referred to Department of Urology, Jikei University Affiliated Kashiwa Hospital. He was diagnosed as having right renal cell carcinoma with vena caval tumor thrombus extending above the diaphragm (T3c) preoperatively. The day before the scheduled day of operation, right pulmonary infarction caused by spontaneous migration of vena caval tumor thrombus of right renal cell carcinoma developed. Although arterial blood gas findings were poor, he only had low grade chest pain without shock. Therefore, we successfully performed right radical nephrectomy and thrombectomy of right pulmonary artery the next day. He was discharged 42 days postoperatively, but, he died from acute heart failure 9 months after the operation.

Aged↗

PubMed2000

Speciation of selenium compounds with ion-pair reversed-phase liquid chromatography using inductively coupled plasma mass spectrometry as element-specific detection.

For selenium speciation analysis, the hyphenation of chromatographic separation with element-specific detection has proved a useful technique. A powerful separation system, which is capable of resolving several biologically and environmentally important selenium compounds in a single column, is greatly needed. However, that has been difficult to achieve. In this paper eight selenium compounds, namely, selenite [Se(IV)], selenate [Se(VI)], selenocystine (SeCys), selenourea (SeUr), selenomethionine (SeMet), selenoethionine (SeEt), selenocystamine (SeCM) and trimethylselenonium ion (TMSe+), were separated by using mixed ion-pair reagents containing 2.5 mM sodium 1-butanesulfonate and 8 mM tetramethylammonium hydroxide as a mobile phase. The separation of these anionic, cationic and neutral organic selenium compounds on a LiChrosorb RP18 reversed-phase column took only 18 min at a flow-rate of 1.0 ml/min with isocratic elution, and baseline separation among the six organic Se compounds was achieved. Inductively coupled plasma mass spectrometry (ICP-MS) was employed as element-specific detection. A comparison of ICP-MS signal intensity obtained with a Barbington-type nebulizer and with an ultrasonic nebulizer (USN) was made. Different signal enhancement factors were observed for the various selenium compounds when a USN was used. The speciation technique was successfully applied to the study on chemical forms of selenium in a selenium nutritional supplement. Selenomethionine was found to be the predominant constituent of selenium in the supplement.

Chromatography, High Pressure Liquid↗

PubMed2000

[Clinical efficacy of cefpirome sulfate against Bacteroides species, Prevotella species and Porphyromonas species. Society of Anaerobic Bacterial Infections in the fields of obstetrics and gynecology in Gifu].

The injectable cephalosporin cefpirome (CPR) was launched in Japan in 1993. It has widely been used in the various infectious diseases. We therefore studied the clinical and bacteriological efficacy of CPR against infections caused by Bacteroides species, Prevotella species and Porphyromonas species frequently isolated from the obstetric and gynecologic infections. Thirteen institutions were involved in this study which ran from March 1994 to January 1999. The administration dosage of CPR was 2 to 4 gram per day administered by drip infusion or intravenous infusion. The duration of treatment was from 3 to 15 days. The evaluations were performed before and after the treatment. CPR was administered to 194 patients with obstetric and gynecologic infections, and 146 of 194 cases were acceptable for the evaluation of drug efficacy. Bacteroides species were identified in 102 patients. Clinical efficacy in 146 cases was excellent in 12 patients, good in 110, fair in 9 and poor in 15 patients. The eradication rate for Bacteroides species could be in 37 cases out of 54 evaluable cases; Prevotella species in 38 out of 49; and Porphyromonas species in 5 out of 5. The overall assessment of bacteriological efficacy was "eradicated" in 91 cases out of 133 (68.4%). Adverse reactions including abnormal findings in laboratory tests were seen in 8 patients (4.76%). Based on these results, CPR promises efficacy and safety in the treatment of obstetric and gynecologic infections due to Bacteroides species.

Adult↗

PubMed2000

[A case of Sipple syndrome whose bilateral pheochromocytomas were resected separately after a 3-year interval].

A 23-year-old woman who had undergone total thyroidectomy and parabronchial lymphadenectomy at the Department of Otolaryngology in our hospital was suspected to have a thyroid carcinoma. Histological examination revealed a medullary carcinoma of the thyroid and normal parathyroid glands. Because a computed tomographic scan after surgery revealed a tumor of the left adrenal gland, the patient was examined at our department two months after the thyroidectomy, 1994. Endocrinic examinations and 123I-MIBG scintigraphy revealed a left adrenal pheochromocytoma of Sipple syndrome. She then underwent left adrenalectomy. Histological diagnosis was pheochromocytoma of the left adrenal gland. Three years after the surgery, a right adrenal tumor was detected by computed tomography. Although results of endocrine examinations were normal, 131I-MIBG scintigraphy showed a hot spot in the right adrenal gland. Right adrenal pheochromocytoma was diagnosed 3 years after surgery for a contralateral adrenal pheochromocytoma. Although surgery was recommended, the patient consented to right adrenalectomy, 1 year later after marriage and before becoming pregnant. Histological examination of the resected specimen revealed pheochromocytoma of the right adrenal gland.

Adrenal Gland Neoplasms↗

PubMed2000

[A case of patent urachus in an adult male].

A 31-year-old man was referred to our hospital for evaluation of urachal rest. The history of his present illness dated back to birth, when the umbilicus was projected and urinary discharge was noted. At that time, the symptom of discharge had spontaneously subsided. At the age of 22, however, the patient again experienced discharge from the umbilicus. Although he did not seek treatment, after six years this symptom disappeared. Around this time, however, pyuria was revealed during medical examination, and abdominal ultrasonography (US) suggested the presence of urachal rest. At the time of hospitalization, physical examination revealed that the patient's right testis was not palpable. He was diagnosed with patent urachus with hemilateral aplasia and monorchism by US, computed tomography, magnetic resonance imaging and cystoscopy. The patient subsequently underwent radical operation. Patent urachus in adults is very rare, and only a few cases have been reported. To our knowledge, only one previously reported case involved a recurrence after spontaneous healing. Further, this is the first report of a patient with patent urachus with hemilateral aplasia and monorchism. Radical operation is generally recommended, based on the fact that very few cases heal conservatively.

Adult↗

PubMed2000

[Clinical statistics on patients and operations during a 20-year period (1978-1997) at Department of Urology, Jikei University School of Medicine].

A statistical analysis was made of diseases, patients, and operations at our department in the four affiliated hospitals of Jikei University School of Medicine from 1978 through 1997. Our findings were as follows. Newly diagnosed urogenital malignancies, except testicular tumors, have been increasing in the last two decades among both outpatients and inpatients. Urogenital infections, including tuberculosis, have gradually been decreasing in the last two decades. The treatment of urinary stone diseases was markedly altered by the induction of extracorponeal shock wave lithotripsy.

Female Urogenital Diseases↗

PubMed1999

Diagnosis of pheochromocytoma using [123I]-compared with [131I]-metaiodobenzylguanidine scintigraphy.

BACKGROUND: Patient with pheochromocytoma (PCT) cannot be cured without operation, therefore, preoperative determination of the localization of PCT should be performed accurately. [131I]-Metaiodobenzylguanidine (MIBG) scintigraphy is a gold standard for the diagnosis of PCT. However, [123I]-MIBG is also found to accumulate in PCT. In order to clarify the usefulness of [123I]-MIBG scintigraphy for the local detection of PCT, we compared the distribution of [123I]- and [131I]-MIBG in patients with or without PCT. METHODS: [131I]- and [123I]-MIBG scintigraphy was performed in 29 and 16 patients, respectively. In the former group, 14 patients had PCT, 12 had hypertension without any adrenal disorder and three had other diseases. In the latter group, eight patients had PCT, two had hypertension without any adrenal disorder and six had other diseases. The sensitivity, specificity and accuracy of [123I]-compared with [131I]-MIBG scintigraphy were compared. RESULTS: The sensitivity of [131I]- and [123I]-MIBG scintigraphy was 85.7 and 90%, respectively. The specificity of each test was 100%. The accuracy of [131I]- and [123I]-MIBG scintigraphy was 93.1 and 95%, respectively. The quality of images obtained using [123I]-MIBG was better than with [131I]-MIBG, because [123I]-MIBG generated a higher dose of gamma-rays with a higher specificity than [131I]-MIBG. In addition, normal adrenal grands were visualized in 50% of patients tested with [123I]-MIBG scintigraphy. CONCLUSIONS: These results indicate that [123I]-MIBG scintigraphy is a valuable tool for the local detection of PCT, as is [131I]-MIBG scintigraphy. Furthermore, it is possible that [123I]-MIBG can be used as an alternative to [131I]-MIBG for the detection of PCT. Our study was not a prospective study and the background of the patients was not matched. Further prospective studies are needed in order to determine the efficacy of [123I]-MIBG scintigraphy for the diagnosis of PCT.

3-Iodobenzylguanidine↗

PubMed1999

[Clinical studies on inverted papilloma of the urinary tract].

BACKGROUND: Inverted papilloma of the urinary tract is believed to be a benign neoplasm based on its histologic morphology and clinical behavior. In recent years, however, several investigators have warned against too optimistic an approach, emphasizing the possibility of malignant cellular transformation within the lesion, or its eventual association with other urothelial tumors such as transitional cell carcinoma or carcinoma in situ. We here report on 35 clinicopathologically diagnosed cases of inverted papilloma, and present the clinical significance attributed to these lesions in view of the current literature. PATIENTS AND METHODS: From 1976 to 1997, 35 cases of inverted papilloma of the urinary tract were treated at our hospital. This report presents the clinical features of these cases, the results of prognosis research, an investigation of the cases in which inverted papilloma and transitional cell carcinoma were found to co-exist, and a discussion of the recurrent cases of inverted papilloma found in previous literature. RESULTS: The patients ranged from 24 to 77 years of age, with a mean of 54 years, and included 4 women and 31 men. The most frequently occurring symptom was grosshematuria, and more than 90% of the 35 cases occurred in the bladder. In 2 of the 35 cases, transitional cell carcinoma coexisted with the inverted papilloma, at a different location in the bladder in one case and within the same neoplasm in the ureter in the other case. Clinical courses after treatment were followed in 29 of the 35 cases, with a follow-up period of from 8 months to 19 years (mean follow-up, 5 years and 4 months). Of these 29 cases, 2 showed recurrence, one at 16 and one at 30 months after the initial resection. Many previous reports show that the association of inverted papilloma and transitional cell carcinoma is stronger in the upper urinary tract and recurrence of inverted papilloma almost always happens with 2 years. CONCLUSION: This study suggests that some cases of urinary inverted papilloma show recurrence or malignant potential. Our results indicate that all cases of urinary inverted papilloma should be treated and followed as cases of low-grade transitional cell carcinomas. Consequently, all cases must be followed for two years or more after the initial operation.

Adult↗

PubMed1998

Isotope dilution analysis of Se in human blood serum by using high-power nitrogen microwave-induced plasma mass spectrometry coupled with a hydride generation technique.

To establish a method for sensitive, accurate, and precise determination of Se in real samples, isotope dilution analysis using high-power nitrogen microwave-induced plasma mass spectrometry (N2 MIP-IDMS) was conducted. In this study, freeze-dried human blood serum (Standard Reference Material, NIES No. 4) provided by NIES (National Institute for Environmental Studies) was used as a real sample. The measured isotopes of Se were 78Se and 80Se which are the major isotopes of Se. The appropriate amount of a Se spike solution was theoretically calculated by using an error multiplication factor (F) and was confirmed experimentally for the isotope dilution analysis. The mass discrimination effect was corrected for by using a standard Se solution for the measurement of Se isotope ratios in the spiked sample. However, the sensitivity for the detection of Se was not so good and the precision of the determination was not improved (2-3%) by N2 MIP-IDMS with use of the conventional nebulizer. Therefore, a hydride generation system was connected to N2 MIP-IDMS as a sample introduction system (HG-N2 MIP-IDMS) in order to establish a more sensitive detection and a more precise determination of Se. A detection limit (3 sigma) of 10 pg mL-1 could be achieved, and the RSD was less than 1% at the concentration level of 5.0-10.0 ng mL-1 by HG-N2 MIP-IDMS. The analytical results were found to be in a good agreement with those obtained by the standard addition method using conventional Ar ICPMS.

Freeze Drying↗

PubMed1998

Impairment of autonomic function induced by posture change in postmenopausal women.

This study was designed to determine if there is a difference in autonomic regulation induced by posture change between postmenopausal and young women. To evaluate autonomic nervous system function, spectral analysis of heart rate variability (HRV) was done in postmenopausal women (n = 13, 46-59 years of age), age-matched men (n = 8, 45-55 years of age), and young women (n = 10, 20-37 years of age) for 3-min periods of controlled frequency breathing (15 breaths/min) in supine followed by sitting positions. In the supine position, the R-R interval variation in older persons decreased significantly compared with that during the follicular phase in young women. Furthermore, the high-frequency (HF) components of HRV, which reflect only parasympathetic activity, were lower in older subjects than in young women. Following a change of position from supine to sitting, the HF component did not change significantly in the postmenopausal women or the men, but the low/high frequency (LF/HF) component ratio, which reflects the balance of autonomic nerve activities, increased significantly in the men. These results suggest that cardiac parasympathetic tone may be reduced in older persons in comparison with young women. Furthermore, arterial baroreflex control of parasympathetic nerve activity caused by posture changes is impaired in the postmenopausal women and aged-matched men. The baroreflex control of the sympathetic component is maintained in the men but not in the postmenopausal women. These differences might result in part from changes in the level of female hormones.

Adult↗

PubMed1998

[Magnetic resonance images of hematospermia].

BACKGROUND: We performed MRI (magnetic resonance imaging) in the pelvic region of 70 cases with hematospermia and conducted a study on the abnormal MRI findings to which hematospermia could be attributed. METHODS: We conducted a study on the morphological anomaly and change in the signal intensity in the prostate gland and of the seminal vesicle as well as on the presence or absence of dilation in the plexus venous surrounding the deferent duct or the prostate gland out of the abnormal MRI findings. As for the seminal vesicle, the patients whose seminal vesicle was seen in higher intensity than the prostate gland in T1 weighted images were diagnosed as having hemorrhagic focus and the patients whose seminal vesicle was seen in low intensity both in T1 and T2 weighted images were diagnosed as having fibrosis caused by chronic inflammation. RESULTS: Abnormal MRI findings were seen in 40 out of the 70 cases (57%). Anomaly in the prostate gland was indicated in 6 (9%) cases. Abnormality in the seminal vesicle was indicated in 30 cases (43%) including hemorrhage of seminal vesicle in 25 cases, chronic inflammation in five cases and cyst of seminal vesicle in one case. CONCLUSION: In conducting an examination of the patients with hematospermia, MRI is the noninvasive and reproducible method and it is possible to identify the hemorrhagic region. Therefore, MRI is thought to be useful to identify the causal organs of hematospermia.

Adult↗

PubMed1997

Visual evoked potential and electroencephalogram of healthy females during the menstrual cycle.

Flash visual evoked potential (VEP) and electroencephalogram (EEG) changes during the menstrual cycle were studied using healthy females having regular menstruation, with 21 at the follicular phase (FP) and 23 at the luteal phase (LP). The following results were obtained. (1) The waveforms of Group Mean VEPs of both groups had approximately similar triphasic contours, consisting of 16 components of P 1-N 8 up to 500 msec of latency. (2) Latencies tended to be longer in LP. (3) Interpeak amplitudes tended to be larger in LP, and one VEP interpeak amplitude (P 5-N 7) of long latency component was significantly larger at LP after eliminating the effect of body height by ANCOVA for 2 CH. (4) Quantitative analysis of EEGs between FP and LP resulted in a tendency for increased alpha, and decreased beta power % at LP. Since estrogen increases the VEP amplitude, and decreases the VEP latency and the alpha activity of EEGs, the large VEP amplitude, the tendency for prolonged VEP latency, and the tendency for increased alpha power % at LP observed in this study indicate that the VEP amplitude at LP reflects the effect of estrogen, and that the VEP latency and EEGs at LP reflect the effect of progesterone.

Adult↗

PubMed1996

Determination of different oxidation states of arsenic and selenium by inductively coupled plasma-atomic emission spectrometry with ion chromatography.

Recent regulation in Japan requires more sensitive trace analysis methods for the determination of arsenic and selenium and their oxidation states As(III) and (V), Se(IV) and (VI). The hydride generation (HG) technique is usually used in combination with AAS and ICP-AES to increase sensitivity. However, hydrochloric acid is mostly used to acidify the sample solution in HG. Isobaric interferences due to chlorine-related species cause mass spectral problems when the same solution is used for the determination of these elements by ICP-MS. In this study, different oxidation states of As and Se were determined by coupling ion chromatography (IC) to an ICP-AES instrument. An HG technique was used to introduce test samples into the ICP. Nitric acid was employed to acidify the samples for HG. The concentrations of acid and base were kept as low as possible to reduce contamination. The formation of As and Se hydrides could be achieved without HCl, if the concentrations of acid and alkaline solutions were optimized. However, HCl was necessary for additional reduction of Se(VI) to Se(IV).

Journal Article↗

PubMed1996

Sex differences in visual evoked potential and electroencephalogram of healthy adults.

Sex differences in flash visual evoked potentials (VEPs) and electroencephalograms (EEGs) were studied in 200 healthy adults (100 females and 100 males). Following results were obtained. (1) Waveforms of Group Mean VEPs of each sex had roughly triphasic contour, consisted of components P1 approximately N8, within 500 msec of latency. (2) Latencies of VEP components by t-test, (3) By analysis of covariance, sex differences in peak-to-peak amplitudes were still significant after eliminating effects of body height, body weight or age, but not those in latencies after eliminating the effect of body height. (4) Quantitative analysis of EEGs resulted in significantly smaller absolute amplitudes, and significantly larger theta, larger beta 1 and smaller alpha 2 power % in females. (5) Peak-to-peak amplitudes of later components in VEPs for 5CH (O1-->Cz) were significantly and positively correlated with EEG absolute amplitudes within each sex group. (6) There were few significant differences in VEP components between follicular phase and luteal phase in females. The sex differences in VEPs verified in this study may be attributed to genetically determined sex differences in neuroendocrinological systems.

Adult↗

PubMed1994

Renal gluconeogenesis in man: comparison with rats and rabbits.

To provide evidence on renal gluconeogenesis in humans and to compare with rats and rabbits, glucose production from several substrates was determined using cortical slices of the three species. In humans, the normal parts of kidney tissue were obtained from six cases of transitional cell carcinoma of the renal pelvis and four cases of renal cell carcinoma. Renal cortical slices were incubated aerobically with or without substrates, and the glucose contents were assayed photometrically. The specificity of human kidneys was evaluated by comparison with the results obtained from rats and rabbits. The rank order of renal gluconeogenesis from various substrates was as follows: Humans: pyruvate > oxaloacetic acid > lactic acid > fructose-1,6-diphosphate > L-glutamine. Rats: pyruvate > fructose-1,6-diphosphate > oxaloacetic acid > lactic acid > L-glutamine. Rabbits: fructose-1,6-diphosphate > pyruvate > oxaloacetic acid > lactic acid >> L-glutamine = 0. In general, the human kidney can produce glucose at the lowest rate among the three species. The substrate specificity of humans was more or less similar to that of rats. These results suggest the existence of a species difference in renal gluconeogenesis both in substrate specificities and quantitative activities.

Aged↗