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Biomedical subjects

Y Okamura

Publications and source records attributed to Y Okamura.

At least 145 records · Page 8Linked to original sources
PubMed1990

[A case of disseminated breast cancer successfully treated with medroxyprogesterone acetate].

We reported the successful treatment of disseminated breast cancer with medroxyprogesterone acetate (MPA). The patient was a 52-year-old female with brain and bone metastasis developed 1 year after surgery. The primary tumor was ER-positive, and she had been treated previously with adjuvant therapy consisting of UFT and tamoxifen. Brain metastasis was surgically removed, but the following combination chemotherapy (epirubicin and vindesine) failed to result in further improvement. Then MPA (1,200 mg/day) was administered as the second-line therapy. After 6 months, multiple bone lesions showed remarkable calcification (PR) and disappeared completely (CR) 13 months later. But the patient was forced to discontinue MPA because of uncontrollable hyperglycemia. At this writing, CR was still being continued and the patient was enjoying favorable quality of life without any treatment. We confirmed that MPA was effective as the second-line treatment for disseminated breast cancer.

Adenocarcinoma↗
PubMed1990

[A case report of Ebstein's anomaly treated with Carpentier's procedure].

A 42-year-old male patient was admitted with congestive heart failure. Echocardiogram and cardiac angiogram revealed Ebstein's anomaly and severe tricuspid valve incompetence. He underwent Carpentier's procedure for the treatment of Ebstein's anomaly. Carpentier's procedure consists of the following two new points; (1) the right atrium and atrialized ventricle is plicated longitudinally; (2) the anterior leaflet and the posterior leaflet of tricuspid valve are transposed with a clockwise rotation to the level of the normal tricuspid anulus. Compared with Hardy's procedure (transverse plication), longitudinal plication preserves the cavity and the function of the right ventricle and excludes atrialized chamber. In our case, there is a trivial residual regurgitation of tricuspid valve postoperatively, but the patient's clinical status has improved remarkably. We conclude that Carpentier's procedure is an effective operation for Ebstein's anomaly.

Adult↗
PubMed1990

[A case report of definitive repair for pulmonary atresia and intact ventricular septum associated with aortic valve regurgitation].

A successful definitive repair for a 10-year-old girl with pulmonary atresia and intact ventricular septum (PA.IVS) associated with aortic valve regurgitation is described. The Fontan type repair was not indicated in this case because of the left ventricular dysfunction due to aortic valve regurgitation and inadequate size of the pulmonary artery. Therefore, right ventricular outflow tract reconstruction, Glen shunt and aortic valve replacement were performed despite severe hypoplastic right ventricle (RVEDVI; 33% of normal) and restrictive tricuspid valve (TVD; 48% of normal). Postoperatively, good result was obtained. There is general agreement that biventricular repair could be safely performed using Glenn shunt, when RVEDVI is above 40% of normal and TVD is above 50% of normal in a patient with PA.IVS. Moreover recently including our case, several successful repairs for PA.IVS with more hypoplastic right ventricle and tricuspid valve have been reported. So it is suggested that the right ventricular outflow tract reconstruction and Glenn shunt can be reliably applied for PA.IVS with more hypoplastic right ventricle and more restrictive tricuspid valve. To our knowledge, this is the first successful report of definitive repair (right ventricular outflow tract reconstruction, Glenn shunt and AVR) for PA.IVS associated with AR.

Aortic Valve↗
PubMed1990

[A long-term follow-up study of intra-arterial infusion chemotherapy in locally advanced breast cancer].

Long-term follow-up results were reported for 61 patients with locally advanced breast cancer treated by intraarterial infusion chemotherapy (IA), compared with those for 96 patients who received no such treatment. The results were as follows. (1) The response rate of the primary lesions to IA was 53.6%, and the post-surgical survival of responders (CR, PR) was significantly better than those of non-responders (NC). (2) Excellent loco-regional control was also achieved in the IA-group. The local recurrence rate was only 16.2%. (3) However, there was no difference between survival rates of each group. The author confirmed that IA was an effective initial treatment for locally advanced breast cancer in terms of loco-regional control, but definite conclusions can be made only after randomized study.

Antineoplastic Agents↗
PubMed1989

Histochemical demonstration of O-glycosidically linked, type 3 based ABH antigens in human pancreas using lectin staining and glycosidase digestion procedures.

Histochemical analyses of the chemical structures of sugar sequences with or without blood group specificity were carried out by combined stepwise digestion of tissue sections with exo- and endoglycosidases and subsequent lectin stainings in formalin-fixed, paraffin-embedded human pancreas. In acinar cells from blood group A or AB secretor individuals, sequential digestion with alpha-N-acetylgalactosaminidase and alpha-L-fucosidase imparted reactivity with peanut agglutinin (PNA) in cells reactive with Dolichos biflorus agglutinin as well as those with Ulex europaeus agglutinin I(UEA-I). Simple fucosidase digestion imparted the PNA reactivity only in UEA-I reactive cells. Sequential digestion with alpha-galactosidase and fucosidase likewise liberated the PNA binding sites in Griffonia simplicifolia agglutinin I-B4 reactive cells from blood group B and AB secretors. Sialidase digestion liberated the PNA binding sites not only in acinar cells but also intercalated duct cells, islet cells of Langerhans and endothelial cells. The PNA reactivity obtained by these enzyme digestions was eliminted by endo-alpha-N-acetylgalactosaminidase (endo-GalNAcdase) digestion. Preexisting PNA affinity in acinar cells from non-secretors was also susceptible to endo-GalNAcdase treatment. Following the endo-GalNAcdase digestion, fucosidase or sialidase digestion recovered the PNA reactivity in acinar cells from nonsecretors. These results show that ABH determinants carried on O-glycosidically linked type 3 chain (D-galactose-(beta 1-3)-N-acetyl-D-galactosamine alpha 1-serine or threonine) are secreted in pancreatic acinar cells and suggest that product coded by the secretor gene is required for the complete conversion of type 3 precursor chains into H determinants.

ABO Blood-Group System↗
PubMed1989

A comparative study of the estrogen receptor ratio in myometrium and uterine leiomyomas.

Estrogen receptor (ER) content in myoma and myometrium was determined by radio-receptor assay (RRA), and ER staining was performed by immunocytochemical staining, i.e. the peroxidase-antiperoxidase (PAP) method, in uterine samples from eight patients with uterine leiomyoma. ER content in myoma tended to be hither than that in myometrium, but the difference was not significant. The distribution pattern of ER staining was thought to be an important criterion. When the data were compared on the basis of the number of cells in the site where the largest number of positive cells aggregated, the number for myoma was significantly higher than that for myometrium (P less than 0.05). These results suggest that myoma contains more ER positive cells to obtain estrogen effects than myometrium.

Female↗
PubMed1989

Further studies on the effect of cyclosporin A on the course of Paragonimus infection in rats.

Paragonimus ohirai-infected rats were treated with cyclosporin A (CyA) at different times during the course of infection. CyA (5 x 80 mg/kg) affected the worm recovery, growth and maturation rates of P. ohirai with respect to control values. This tendency was most remarkable in animals treated 15 days and more after infection with CyA (groups B, +15 to +19 days; C, +25 to +29; D, +35 to +39 and E, +45 to +49). In group A (0 to +4), however, the drug did not affect markedly the growth and maturation of worms, although it significantly lowered worm recovery rates. CyA administration also affected normal migration of P. ohirai in the highly susceptible host (rat), when the drug was administered during the peritoneal and/or liver phase of infection. Thus, in this P. ohirai/rat model, CyA significantly reduced worm recovery rates, and affected the growth, maturation and migration of the worms depending on the time of administration.

Animals↗
PubMed1989

Histochemical analysis of the chemical structure of blood group-related carbohydrate chains in serous cells of human submandibular glands using lectin staining and glycosidase digestion.

Using lectin staining methods in combination with exo- and endo-glycosidase digestion procedures, we analyzed the chemical structure of different types of blood group-related substances in serous cells of formalin-fixed, paraffin-embedded human submandibular glands. Serous cells produced only H antigen; A and B antigens were not present, and the expression of H antigen is dependent on the secretor status of the tissue donor. Although reactivity with Ulex europaeus agglutinin I (UEA-I) was not markedly reduced by alpha-L-fucosidase digestion, an affinity for peanut agglutinin (PNA) was seen after fucosidase digestion in the cells from secretors. In those from nonsecretors, no PNA reactivity appeared after enzyme digestion. On the other hand, sialidase digestion elicited PNA reactivity in serous cells irrespective of the donor's secretor status. PNA reactivity observed after fucosidase or sialidase digestion was susceptible to endo-alpha-N-acetylgalactosaminidase (endo-GalNAc-dase) digestion. SBA reactivity in UEA-I-negative cells from secretors, or in cells from fetuses and newborn infants, was markedly reduced by beta-galactosidase digestion. After galactosidase digestion, reactivity with Griffonia simplicifolia agglutinin II (GSA-II) appeared in the corresponding cells. This GSA-II reactivity was almost completely eliminated by subsequent beta-N-acetylhexosaminidase digestion. Whereas PNA reactivity in these cells was not reduced by beta-galactosidase treatment, it was significantly diminished by endo-GalNAc-dase digestion. These results suggest that at least two kinds of precursor disaccharides are produced in submandibular serous cells, i.e., SBA-reactive D-galactose-(beta 1-3,4)-N-acetyl-D-glucosamine and PNA-reactive D-galactose-(beta 1-3)-N-acetyl-D-galactosamine alpha 1-serine or threonine (O-glycosidically linked Type 3 chain or T antigen). Final fucosylation and synthesis of these two types of precursor chain appear to be under the control of the secretor gene.

ABO Blood-Group System↗
PubMed1989

Hypothalamic neurons from a developmental aspect.

The development of hypothalamic neurons was examined in vivo and in transplanted grafts in rats. The neurons appeared in vivo in distinctive chronotopical schedules showing such morphological characteristics as synaptocrine or hemocrine neurons. These phenotypical properties seemed to be primed already by day 12.5 of gestation in rats, because the grafted hypothalamic primordia from 12.5-day-old embryonal rats differentiated neurons, which express these neuronal properties in the third ventricle of adult female rats. The synaptocrine neurons projected to other neurons, suggesting the establishment of synaptic contacts, and the hemocrine neurons projected to vasculatures developed in the grafts, suggesting the accomplishment of neurovascular associations.

Animals↗
PubMed1989

[Establishment of primary culture of cells derived from human uterine endometrium].

A culture of cells derived from the endometrium was established to study in vitro the effects of hormone on the endometrium. Endometrial tissue was cut into small pieces and suspended in trypsin and collagenase-containing medium. The primary cell culture was obtained by six passages. The following observations appeared to indicate that the cultured cells consisted of endometrial epithelium-derived adenocytes, endometrial stromal cells and fibroblasts: 1. The epithelium-derived adenocytes and the endometrial stromal cells were positive and the fibroblasts were negative for staining with keratin by the enzyme-labelled antibody method. 2. Transmission electron microscopic observation revealed microvilli on the surface of the adenocytes, abundant free ribosomes in the cytoplasm, and nucleoli in distinct nuclei whose margin was deeply stained. Junction complexes among the cells were also observed. There were no microvilli on the surface of the endometrial stromal cell. Filaments, mitochondria and secreting granules were distinctly seen in the cytoplasm. The adenocytes on the margin of the nucleus itself were more deeply stained, and the margin was notched. The fibroblasts were spindle-shaped, and there no basement membrane structure laterally along the surface of the fibroblast. There were no intercellular junction complexes but there were filaments in the intercellular borders and in the cytoplasm. Chromatin in the large oval nuclei was dispersed.

Adult↗
PubMed1989

[Clinical evaluation of perioperative myocardial infarction as a complication of valve replacement].

Perioperative myocardial infarction (PMI) is a well-known complication of coronary artery surgery, but rarely encountered in valvular surgery. We have experienced 6 cases of valve replacement with PMI, using blood cardioplegia since 1979. Those patients (5 men, one woman; mean age 47 +/- 8 years) had no previous angina, and preoperative CAG revealed no significant stenosis. Three patients were reoperative cases. A diagnosis of PMI was established by the following criteria; an abnormal increase in maxCPK-MB (greater than 150 IU/l), new Q waves at ECG, positive 99mTc-PYP scan (grade 3-4). The area of PMI was inferior in 4 patients, posterior in one, and anterior infarction was seen in only one case. Three cases required IABP, but all 6 cases showed good exercise capacity by Treadmill exercise test in late stage. Several factors are thought to be the cause of PMI at valvular surgery; such as coronary air embolism, perioperative coronary spasm, inappropriate topical hypothermia, etc. Prognosis is not necessarily poor, however much attention should be paid to prevent PMI in valve replacement.

Adult↗
PubMed1989

[Changes in autonomic nerve function during the normal menstrual cycle measured by the coefficient of variation of R-R intervals].

The purpose of this study was to determine if there is a change in autonomic nerve function during the menstrual cycle. The subjects were 20 females (average age 26.1 years +/- 4.6) with a normal menstrual cycle. The coefficient of variation of R-R intervals (CV R.R) was measured to investigate autonomic function in the menstrual, follicular, ovulatory, luteal, and premenstrual phases. Average CV R-R for all phases was 5.2 +/- 1.9%. And the CV R-R tended to be lower in those in their 30s than in those in their 20s. And no noticeable difference was seen in the CV R-R among the 5 phases of the menstrual cycle. On the other hand, the CV R-R of 11 females with premenstrual syndrome was low in the ovulatory, luteal and premenstrual phases. These results, which provide basic data for clinical use, suggest the following. (1) The age of subjects should be taken into consideration. (2) Changes in the CV R-R during the menstrual cycle are negligible. (3) However, in those showing symptoms associated with the menstrual cycle such as premenstrual syndrome, changes during the menstrual cycle should be taken into account. At the same time psychological changes in the subjects were evaluated by the following tests: Cornell Medical Index, Taylor's manifest anxiety scale, and Zung's self-rating depression scale. The results of these tests did not vary significantly during the menstrual cycle.

Adult↗
PubMed1989

[Clinical study of blood cardioplegia--for aerobic metabolism during aortic cross-clamping].

Blood cardioplegia is considered to be superior in oxygenating potential, buffering potential, oncotic, and other physiologic effects. In clinical cases, however, it is unproven whether aerobic metabolism can be obtained by using blood cardioplegia during aortic cross-clamping. Aerobic metabolism during aortic cross-clamping was therefore evaluated in patients with valvular heart disease who underwent relatively long periods of ischemic arrest. Myocardial metabolism of oxygen, lactate and pyruvate was studied in 14 patients under 126 +/- 41.2 min of cardiac arrest, and intramyocardial carbon dioxide tension (PmCO2) was also monitored continuously in 23 patients who received 121 +/- 29.8 min of aortic cross-clamping. After aortic cross-clamping, 4 degrees C St. Thomas solution was infused for immediate cooling, followed by blood cardioplegia for replenishment every 20-25 min. Blood cardioplegia and myocardial temperature were maintained within 15-20 degrees C by using an automatic cardiac hypothermia control system. Myocardial oxygen extraction during the pre-ischemic period was 26.8 +/- 13.3%. At 15 and 30 min after reperfusion, it was 30.0 +/- 10.8% and 33.8 +/- 8.2%, respectively. During ischemic arrest, myocardial oxygen extraction decreased, but the infusion of blood cardioplegia kept it above 14.0 +/- 9.3% at all times. As for lactate metabolism, although some cases showed lactate production even before the aortic cross-clamping, lactate extraction was attained in some cases during blood cardioplegia perfusion. Changes in excess lactate and redox potential of lactate and pyruvate (delta Eh) showed that aerobic metabolism could be obtained in 13/32 (41%) infusions of blood cardioplegia. PmCO2 at the aortic cross-clamp was 47.0 +/- 27.7 mmHg, and gradually rose during the ischemic arrest, but only as far as 68.4 +/- 64.8 mmHg at the time of cross-clamp release. PmCO2 decreased with each infusion of blood cardioplegia, and the decrease lasted up to 10 minutes. Though PmCO2 began to rise thereafter, the effect of blood cardioplegia continued as long as 20-25 min after the infusion. In conclusion, blood cardioplegia provides aerobic metabolism during aortic cross-clamping even in clinical setting, provided that cardiac hypothermia and delivery of cardioplegic solution are maintained appropriately.

Aerobiosis↗
PubMed1989

[Long-term survival in patients with breast cancer after intra-arterial infusion chemotherapy].

Twenty two patients with locally advanced breast cancer survived for more than 5 years after intra-arterial infusion chemotherapy (IA). In this study, we compared these long-term-survivors with thirteen cases who died within 2 years. The results were as follows. (1) ER positive rate of the long-term-survivors (90%) was significantly higher than in short-term-survivors (25.0%). (2) There was no difference between the response rates of each group; 63.2% in long-term-survivors vs. 53.8% in short-term-survivors. (3) Adjuvant endocrine therapies were carried out in the former group, and their D.F.I. were considerably longer than in the latter group. (4) Common sites of recurrence in long-term-survivors were soft tissues and bones, compared with visceral in short-term-survivors. Post-recurrence survivals of the former were, also, longer than in the latter. From these results, we confirmed that preoperative IA and following adjuvant endocrine therapies induces favorable results in the treatment of hormone sensitive breast cancer.

Breast Neoplasms↗
PubMed1989

[Five cases of the double renal pelvis and ureter].

Five cases of the double renal pelvis and ureter were encountered among 340 cadavers for dissection practice. Number of minor calices and their surface area in these kidneys were calculated, and causal relationship to abnormal organogenesis was discussed. These 5 cases were formal exclusively in consist of males; 4 right sides and 1 left side, 2 complete duplications and 3 partial duplications. The 5 cases were divided into 2 groups by the number and surface area of minor calices in upper and lower pelvises as follows: 1) The number and surface area of minor calices in the upper pelvis and the lower pelvis were respectively equivalent to the mean value of those in one normal kidney (case 1). 2) The sum of the number and surface area of minor calices in the upper and those in the lower pelvises were equivalent to the mean value of those in one normal kidney (case 2-5). These cases give useful criteria for classification of the double renal pelvis and ureter.

Adult↗
PubMed1988

Double immunoelectron microscopic labelings of human chorionic gonadotropin and human placental lactogen in human chorionic villi.

Simultaneous immunoelectron microscopic localization of human chorionic gonadotropin (HCG) and human placental lactogen (HPL) was examined on the same ultrathin section of human chorionic villi by means of the double labeling technique. Using specific rabbit antisera against HCG and HPL followed by goat anti-rabbit IgG-coated colloidal gold of different sizes (15 nm and 5 nm), immunoreactions of HCG were concentrated on middle-sized secretory granules of 200-300 nm and large dense bodies of 500-1000 nm, while those of HPL were exclusively located on small secretory granules of 80-180 nm. The present experiment provides direct evidence for our previous data that HCG and HPL seem to be stored in different granular components in the syncytiotrophoblast.

Chorionic Gonadotropin↗