Search PubMed⌕ Search

Biomedical subjects

S Nakae

Publications and source records attributed to S Nakae.

At least 73 records · Page 4Linked to original sources

The cochlea of the spontaneously diabetic mouse. II. Electron microscopic observations of non-obese diabetic mice.

We used transmission electron microscopy to examine the cochlea of non-obese diabetic mice as animal models for human type I or non-insulin-dependent diabetes mellitus. Pathological changes were observed in the organ of Corti of the basal turn and in the stria vascularis of each turn. Major findings in the stria vascularis were protrusion or condensation of marginal cells, swelling of intermediate cells, and widening of the intercellular spaces. Principal findings in the organ of Corti involved degenerative changes of the outer and inner hair cells and replacement of hair cells by supporting cells. No prominent pathological changes were observed in the capillaries. The possible mechanism of diabetic involvement in cochlear pathology is discussed.

Animals↗

The cochlea of the spontaneously diabetic mouse. I. Electron microscopic observation of KK mice.

We examined the cochleae of the spontaneously diabetic KK mice by using transmission electron microscopy. At the age of 3 months, the mice started to show evidence for glycosuria and hyperglycemia, and tissue sections showed beginning cochlear pathology. The pathological changes present were found to be limited to the stria vascularis: protrusions of marginal cells, swellings of intermediate cells and widening of intercellular spaces were the main findings seen. These changes progressed with age, but were not observed in age-matched non-diabetic 57BL/6 mice. The possible mechanism of diabetes causing cochlear pathology is discussed.

Animals↗

[Mitotic activity of cancer cells and survival of gastric cancer patients].

An in vivo stathmokinetic method was used to analyze the mitotic activity of cancer cells from 43 gastric cancer patients. The mitotic activity was distributed between mitotic index (MI) 40.0% and MI 127.0%. The patients were classified into 3 groups; low mitotic activity (L-MA) group (MI less than 70.0%), middle mitotic activity (M-MA) group (70.0%) less than or equal to MI) 90% and high mitotic activity (H-HA) group (MI greater than 90.0%). Survival curve and average survival period were examined and compared with each of 3 mitotic activity groups. The survival curve of L-MA group was better than that of M-MA group (generalized Wilcoxon test, Z = 1.815, p less than 0.1), and the latter was significantly better than that that of H-MA group (generalized Wilcoxon test, z = 2.048, p less than 0.05). Average survival period (mean +/- S.D.) of dead patients from cancer recurrence was 24.0 months in L-MA group (n = 1), 16.1 +/- 2.4 months in M-MA group (n = 9) and 7.4 +/- 2.4 months in H-HA group (n-13). Patients with gastric cancer of high mitotic activity died earlier than patients with that of low mitotic activity in the identical histologic type, identical degree of cancer invasion and the identical stage of cancer. The results suggested that the mitotic activity of cancer cells was utilized as a new prognostic parameter of gastric cancer.

Adenocarcinoma, Mucinous↗

Assessment of left ventricular function before and after Fontan's operation for the correction of tricuspid atresia. Changes in left ventricular function determined by left ventricular volume change.

Functional change in the left ventricle was studied in the light of changes in the left ventricular (LV) volume preload before and after Fontan's operation. Six cases with tricuspid atresia (TA) were studied, and they had either types Ib or IIb. The preoperative LV end-diastolic volume index (LVEDVI) was 123 +/- 44 ml/m2, which corresponds to 166% +/- 45% of normal values. This suggests that in TA the preload of the LV volume is increased because of its peculiar hemodynamic situation. After Fontan's operation, the LVEDV decreased by 24.6% to 119.6 +/- 87.7 ml (P = 0.01), which corresponds to 120% +/- 50.9% of normal values. Presenting a striking contrast to the decrease in LVEDV, the postoperative reduction in LV end-systolic volume (LVESV) was approximately 8%. Preoperative and postoperative values for LVESV were 67.1 +/- 50.8 ml and 62 +/- 45.6 ml, thus, the systolic volume was decreased. Because of the small change in LVESV, the ejection fraction (EF) of the left ventricle significantly decreased from 0.61 +/- 0.1 preoperatively to 0.48 +/- 0.1 postoperatively. The cardiac index (CI) remained in the range of 1.9-2.5 l/min/m2 with a mean of 2.2 +/- 0.2 l/min/m2 at 1 month after operation. But, later, improvement in EF was observed in one case, in which the CI increased from 2.5 to 3.2 l/min/m2.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Freeze-replica observations of guinea pig middle ear muscles.

The histological characteristics of the middle ear muscles, Musculus tensor tympani and M. Stapedius, of the guinea pig were studied using freeze-fracturing technique. No gap junction was observed but the tight junction was found in the tensor tympani muscle, possibly between muscle cells. No distinct difference was found between the size distributions of the apertures and caveolae on the fracture face of the sarcolemma of the two kinds of muscles.

Animals↗

Dynamics of right heart flow in patients after Fontan procedure.

In seven patients who underwent Fontan procedures but in whom no valves were inserted, dynamics of right heart flow were evaluated with the use of a catheter-tipped velocity transducer, pulsed Doppler echocardiography, and angiocardiography. Right atrial (RA) contraction caused a forward flow to the pulmonary artery (PA) and a backward flow to the inferior vena cava (IVC). Backward flow to the superior vena cava (SVC) was minimal. As the right atrium relaxed, a rapid forward flow occurred at the IVC and SVC that filled the atrium and a small amount of pulmonary regurgitant flow was observed. Subsequently, a forward flow was observed at the IVC, SVC, and PA during RA diastole. Angiographically determined RA stroke volume (SV) was less than 40% of the left ventricular (LV) SV in three patients in whom the postoperative increase in atrial "a" wave pressure (delta p) was greater than 8 mm Hg, while it was similar to or greater than LVSV in four patients in whom delta p was 6 mm Hg or less. In all patients LV end-diastolic volume was 107 +/- 27(SD)% of normal but LV ejection fraction was 0.53 +/- 0.07, resulting in the reduced cardiac output (2.8 +/- 0.7 l/min/m2). There was no correlation between the RASV or RA ejection fraction and cardiac output. These data show that the RA contraction causes a forward flow to the PA and that pulmonary regurgitation is not significant after Fontan procedure even when valves are not inserted. Also, the postoperative increase in the RA afterload may depress RA function.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

[A clinicopathological study on hematogenous recurrence of colo-rectal cancer--with special reference to prediction and prevention of the recurrence].

Hematogenous recurrence was investigated in 325 cases of colo-rectal cancer. Hematogenous recurrence was confirmed in 34 cases including 25 liver, 5 lung, 2 bone, one brain and one skin recurrence. Most of the cases (28 cases, 82.4%) revealed a single or multiple hematogenous recurrences without showing additional other types of recurrence. Histological examination of cancer lesions indicated that patients with the findings consisting of moderate and/or high grade of vein invasion (v2-3), subserosal and extramural vein invasion with node metastasis showed high recurrent rate. One and two year survival rate of the patients treated with MF-MF' adjuvant chemotherapy was greater those the patients with F-F' chemotherapy or those without chemotherapy. However, 3-, 4- and 5- year survival rate did not show significant difference among 3 therapeutic groups. The analysis of survival curves also indicated no significant difference among 3 therapeutic groups. These results may suggest that hematogenous recurrence is derived from pre- and/or intra-operative micrometastasis or transplantation of cancer cells, that patients with the above mentioned histological evidence must be clinically treated as a high risk group for recurrence and that MF-MF' adjuvant chemotherapy can be effective in lowering the recurrence rate during the first one or two years after operation.

Antineoplastic Agents↗