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Biomedical subjects

M Nitta

Publications and source records attributed to M Nitta.

At least 127 records · Page 7Linked to original sources
PubMed1988

Diagnostic accuracy of continuous wave Doppler echocardiography in severe aortic stenosis in the elderly.

Forty-four male patients (mean age 63.6 years) with aortic stenosis (AS) were evaluated by conventional hemodynamic methods and continuous wave (CW) Doppler echocardiography. The relationship between Doppler mean gradients and direct mean pressure gradients in all patients was significant, with an r value of 0.88. Sixteen of 17 patients with a mean Doppler gradient greater than or equal to 40 mmHg had severe AS (AVA less than or equal to 1.0 cm2). Twenty-seven patients had a Doppler gradient less than 40 mmHg, and 8 of these patients had severe AS (AVA less than or equal to 1.0 cm2). The sensitivity and specificity of a Doppler gradient greater than or equal to 40 mmHg in detecting severe AS were, therefore, 67% and 95%, respectively. Thirty-three percent (8/24) of patients with severe AS and low Doppler gradients (less than 40 mmHg) had evidence of poor left ventricular function, evidenced by a lower cardiac output, a higher heart rate and an abnormal PEP/LVET ratio compared to the other patients. Thus, the presence of a low stroke volume less than or equal to 60 ml/beat and PEP/LVET x HR greater than 26 is of value in identifying patients where the Doppler is likely to significantly underestimate the degree of aortic stenosis.

Adult↗
PubMed1988

DIDMOAD (diabetes insipidus, diabetes mellitus, optic atrophy and deafness) syndrome associated with myocardial disease.

A 30 year old man with DIDMOAD (diabetes insipidus, diabetes mellitus, optic atrophy and deafness) syndrome associated with myocardial disease is reported. Echocardiographic study revealed a marked symmetric left ventricular hypertrophy. Histology of the endomyocardial biopsy specimen from the right ventricle showed severe glycogen deposition in the myocytes. This case may indicate that DIDMOAD syndrome is a hereditary systemic disease affecting multiple organs, including the myocardium.

Adult↗
PubMed1988

[Combined cell killing effects of anticancer drugs and hyperthermia in vitro].

Using an in vitro colony forming assay system, cytotoxic effects of anticancer drugs, adriamycin (ADM) and peplomycin (PEP), and the combined effect of hyperthermia and anticancer drugs on cultivated KK-47 cells were investigated. From the response curves obtained at 42 and 43 degrees C hyperthermia, 20% growth inhibition time (IT20) at 42 and 43 degrees C hyperthermia and 50% growth inhibition time (IT50) at 43 degrees C were calculated. The IT20 and IT50 hyperthermia were combined with a 2-hour treatment of each of the anticancer drugs. When the hyperthermia was combined with various concentrations of ADM ranging from 0.005 to 0.1 microgram/ml, enhanced cell killing effects were obtained at the concentrations of less than 0.02 microgram/ml of ADM, whereas, there was no increase in cell killing effect at the concentrations of more than 0.05 microgram/ml of ADM. The combination of hyperthermia with PEP considerably enhanced the cell killing effects with an increase of PEP concentration.

Bleomycin↗
PubMed1988

[A case of bilateral testicular tumors showing remarkable regression of huge metastatic tumors after VAB-6 combined chemotherapy].

A case of bilateral testicular seminomas with abdominal huge metastatic tumors is presented. The patient is a 23-year-old male. An abdominal huge mass was found incidentally by a physician. CT scan and ultrasonography revealed the presence of the tumor in the left retroperitoneal space and biopsy specimen of the abdominal tumor was diagnosed as seminoma. On March 7, 1985, he was referred to our clinic. Bilateral testicular tumors were detected on palpation and ultrasonography. Bilateral orchiectomy was performed. Histological diagnosis was pure seminoma. After four sessions of VAB-6 combined chemotherapy, the abdominal tumor, 14.1 x 12.3 cm in size, decreased to 5.7 x 4.4 cm ( a regression rate of 85.5%). Retroperitoneal lymph-node dissection was undertaken, but the abdominal tumor could not be resected completely. Histological examination of the resected tumor revealed complete necrosis of the tumor tissue. After the operation, one session of the chemotherapy and irradiation were added. A total of 109 cases of bilateral testicular germ cell tumors in Japan was reviewed.

Adult↗
PubMed1988

Progression of aortic stenosis in the elderly detected by noninvasive methods.

One hundred eighty consecutive male patients, mean age of 64.6 years, who were referred to cardiac catheterization for the evaluation of aortic stenosis (AS), were studied using a noninvasive scoring system. The system is based upon 7 variables including: 1) LVH by ECG, 2) aortic valve calcium by chest x-ray, 3) loudness of A2, 4) Q to peak of murmur, 5) T time of the carotid pulse, 6) LV ejection time and 7) LVH by echocardiography. The scoring system has a range from 0 to 16, and a score greater than or equal to 5 indicates severe AS (valve area less than or equal to 1.0 cm2). Eighteen patients had hemodynamic studies on two occasions. In 3 years progression of stenosis was evident by an increase in the mean aortic valve gradient from 23 +/- 3.4 mmHg to 44 +/- 4.2 mmHg (p less than 0.005). The aortic valve area decreased from 1.4 +/- 0.1 cm2 to 0.76 +/- 0.07 cm2 (p less than 0.005). Noninvasive scores increased in these patients from 2.1 +/- 0.5 to 7.6 +/- 1.0 (p less than 0.005). Fifty-one patients had repeated noninvasive studies. Twenty-two patients, who had mild AS at the initial evaluation, attained a score of greater than or equal to 5 in 3 years, indicating probable progression to severe AS. The mean initial score was 2.3 +/- 0.4, and the score at the end of the mean follow-up period of 3 years was 8.0 +/- 0.6 (p less than 0.005).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1987

Noninvasive evaluation of the severity of aortic stenosis in adults.

A noninvasive point score system for the evaluation of severity of aortic stenosis (AS) was employed in a prospective study of 153 patients (mean age 64.8 +/- 0.8 years) referred from invasive studies or for the evaluation of a systolic murmur. Seven variables were recorded and scored as follows: LVH by ECG (0-2); aortic valve calcium by chest x-ray film (0-2); loudness of A2 (0-2); Q-peak of murmur (0-3); T-time of carotid pulse (0-3); ejection time (0-3); and LVH by echo (0-1). Range of the total score was 0-16. All patients had the aortic valve area (AVA) determined by cardiac catheterization. Data analysis revealed that the relation between the total score and the AVA was curvilinear with a score greater than or equal to 5 correctly identifying 100/107 (93 percent) of patients with a valve area of less than or equal to 1.0 cm2. If the patients with an AVA of less than or equal to 1.0 cm2 were considered severe and patients with a total score less than 5 were considered mild-moderate, the sensitivity, specificity, and predictive accuracy for a score greater than or equal to 5 were 93 percent, 96 percent, and 98 percent, respectively. The relation between the score and aortic valve gradient (AVG) was linear with a score of greater than or equal to 5 correctly identifying 84/88 (95 percent) with an AVG greater than or equal to 40 mm Hg. If the patients with a pressure gradient over 40 mm Hg were considered severe, the sensitivity, specificity, and predictive accuracy for a score greater than or equal to 5 were 95 percent, 72 percent, and 82 percent, respectively. It is concluded that a point score system employing seven noninvasive variables is simple and accurate in identifying patients with severe AS and would be a valuable addition to a Doppler determined gradient.

Adult↗
PubMed1987

Progression of aortic stenosis in adult men. Detection by noninvasive methods.

One hundred seventy-one patients with aortic stenosis (AS) who had hemodynamic studies were evaluated by a scoring system of the seven following noninvasive variables which our laboratory had developed to estimate the severity of AS: left ventricular hypertrophy (LVH) by ECG; visible aortic valve calcification by chest x-ray examination; loudness of A2; Q to peak of systolic murmur; T-time of the carotid pulse; LV ejection time; and LVH by M-mode echocardiography. The range of the severity score is 0 to 16, and a score greater than or equal to 5 has been shown correctly to identify 93 percent of patients with severe AS (valve area less than or equal to 1.0 cm2). The present study has applied this method to the detection of progression of AS. Eleven patients (mean age, 60.4 years) were studied who had hemodynamic studies performed two to nine years apart (mean, three years). Progression of stenosis occurred in all, with an increase in mean aortic valve gradient from 23 +/- 4.7 mm Hg to 46 +/- 6.5 mm Hg (p less than 0.005). Aortic valve area decreased from 1.5 +/- 0.18 cm2 to 0.88 +/- 0.10 cm2 (p less than 0.005). Noninvasive scores increased in these patients from 0.7 +/- 0.5 to 7.1 +/- 2.3 (p less than 0.005). Thirty-five patients (mean age, 62.4 years) had repeat noninvasive studies one to six years apart (mean 3 years). Twenty-two (63 percent) had an increase in the noninvasive score of greater than or equal to 3 points, and 20 (57 percent) attained a score of greater than or equal to 5, indicating probable severe AS. The mean initial severity score was 2.2 +/- 0.3, and at the end of a mean follow-up of three years, the score was 8.3 +/- 0.6 (p less than 0.005). It is concluded that in the elderly male, progression of AS over a three-year period occurs in about 60 percent of patients, and progression can be detected by simple, noninvasive methods.

Adult↗
PubMed1987

Transmission characteristics of pulse waves in the intracranial cavity of dogs.

Systems analysis of intracranial pressure pulse waveforms was carried out in six dogs under conditions of normocapnia and intracranial normotension to determine how the pressure pulse is transmitted through the intracranial cavity. Since the intracranial cavity can be regarded as a system, systems analysis was applied to it. The pressure pulse wave of the common carotid artery was used as the input signal and the epidural pressure pulse wave as the output signal. An attempt was made to randomize the input signal using a cardiac pacemaker or an aorta balloon. The transfer function of the system was estimated numerically from the autocorrelation function of the input signal and the cross-correlation function of the input and output signals by means of the least-squares method. Some characteristics of pressure transmission through the system were observed. The gain curve of the system decreased between 1 and 7 Hz, then suddenly increased to form a marked peak at about 10 to 15 Hz, where the phase curve also changed from positive to negative. These results suggest that the lower frequencies of the pulse wave were suppressed during transmission through the intracranial cavity, whereas the greatest acceleration in transmission occurred at about 10 to 15 Hz. In addition, resonance was evident in the intracranial cavity under normal intracranial conditions. This is the first report of such resonance.

Animals↗
PubMed1987

[Wilms' tumor in an adult patient: a case report].

A case of Wilms' tumor in an adult patient is presented. The tumor in adults is rather rare and has an unfavorable prognosis. A 39-year-old man bruised his left flank while skiing in February, 1983. He noticed severe left flank pain. The pain subsided after a week of rest. However, he complained of left abdominal mass and dull pain again, and consulted our outpatient clinic on May 21, 1983. Left transperitoneal nephrectomy was performed under a diagnosis of left injured renal tumor. Histological diagnosis was nephroblastoma. A combined chemotherapy of actinomycin D (ACD) and vincristine (VCR) was started after operation. A total of 10 mg of ACD and 14 mg of VCR was administered by the end of 1983. In March 1984, however, a local recurrence and pulmonary metastases of the tumor were detected by CT and chest films. Local RF-hyperthermia combined with irradiation, alpha-interferon or chemotherapy using cisplatin and adriamycin was given. The patient died of profound cachexia in December, 1984 after gradual deterioration of general conditions.

Adult↗
PubMed1987

[Combined treatment of irradiation and 8 MHz radiofrequency hyperthermia with chemoembolization in advanced renal tumor].

A combined treatment of irradiation and 8 MHz radiofrequency hyperthermia after chemoembolization, using 20 mg of microencapsulated mitomycin C (MMC.mc), was undertaken in a patient with an advanced left renal tumor. The patient, a 70-year-old man, noticed a gross hematuria in February, 1984. CT showed a left renal tumor, 88 X 70 mm in size. Histological examination revealed clear cell carcinoma of the left kidney. The tumor was unresectable because of an invasion into the surrounding tissues. Chemoembolization was performed before the combined treatment of irradiation and hyperthermia. He received 23.2 Gy of irradiation and 10 sessions of hyperthermia. Intratumoral temperature reached 42.6 degrees C during the heating. After treatment, there was a tumor regression rate of 58%, as well as pain relief, and an improvement in his appetite loss. He died 8 months after this treatment. An autopsy specimen revealed bionecrotic tumor cells among the prominent necrotic and fibrotic tissues.

Aged↗
PubMed1987

[Malignant lymphoma from left renal capsule: report of case].

A 59-year-old woman was admitted to our clinic with the complaint of left flank pain. Excretory urogram showed left hydronephrosis. Computed tomographic (CT) scan and renal angiography showed a left renal capsular tumor. Histological specimen obtained by a sure cut needle suggested malignant lymphoma. She was treated with a combined treatment of 8 MHz radiofrequency hyperthermia in a total of 10 sessions and 5,440 rads irradiation for 5 weeks. After the treatment, CT scan showed 92% tumor regression. After that, a recurrent tumor in left shoulder muscle became manifest. She received combination chemotherapy with 3 courses of ABEP regimen (aclacinomycin, cytosine arabinoside, etoposide, prednisolone) and 7 courses of ACOPE regimen (adriamycin, cyclophosphamide, vincristine, prednisolone, etoposide) and complete remission was obtained.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1987

Conduction disturbances associated with mitral anular calcification.

To investigate the apparent association of mitral anular calcification (MAC) and electrocardiographic abnormalities, the relation between the location of two-dimensional (2D) echoquantified MAC and conduction disturbances was studied in 140 patients with MAC (MAC group) and 135 age- and sex-matched patients without MAC (control group). The MAC group was subclassified regarding the site and severity of calcium in the mitral anulus. The site of MAC was defined as Type I of MAC near the conduction system and Type II of MAC away from the conduction system. The severity of MAC was graded on 2D echocardiography as mild (localized within 1 segment) and moderate to severe (more than 1 segment). Seven patients with MAC, and only one control subject, had pacemakers in place. Conduction disturbances were present in 44 (31%) of 140 patients with MAC and in 37 (27%) of the 135 control patients (no significant difference). But there were more conduction disturbances in the patients with Type 1 MAC (53%) than in those with Type II MAC (26%) (p less than 0.01). Specifically, complete left bundle branch block and intraventricular conduction delay were more prevalent when MAC was near the conduction system. Intraventricular conduction delay also was more prevalent in the patients with Type I MAC than in the control group (Type I: 12% vs control: 4%; p less than 0.05). These data suggest that moderate to severe degrees of MAC located near the conduction system are associated with conduction disturbances, especially intraventricular conduction delay.

Aged↗
PubMed1986

Effects of an expanding supratentorial mass on the auditory brain-stem responses in baboons.

This study was carried out to investigate the effects of an expanding supratentorial mass on auditory brain-stem responses (ABRs). A balloon was inserted into the supratentorial epidural space of seven baboons (in two cases, in the right occipital area; in five cases, in the right temporal area). The balloons were inflated at a rate of 0.2 ml/minute to increase intracranial pressure (ICP). ICP (right frontal epidural pressure) and blood pressure (BP) were continuously recorded. Recordings of ABRs (vertex to mastoid on both sides) were made serially. Pupillary changes were also recorded. At 30 mmHg ICP, the amplitude of wave V on the right side was observed to be significantly attenuated (p less than 0.02). At 50 mm Hg ICP, the latency of wave V on the right side was significantly prolonged compared with that at 30 mm Hg ICP (p less than 0.02). At 70 mmHg ICP, significantly decreased amplitude of wave V on the left side was also observed (p less than 0.02, from the control), associated with significant increased latency of wave IV on the right side (p less than 0.01, from the control; p less than 0.05, from 50 mm Hg ICP). Finally, waves IV and V on both sides substantially disappeared at 100 mm Hg ICP. Anisocoria appeared in four animals at 30-50 mm Hg (mean +/- SD; 45 +/- 8.7) ICP. The amplitude of wave V was significantly decreased in these circumstances (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗