Biomedical subjects

I Nagata

Publications and source records attributed to I Nagata.

At least 199 records · Page 11Linked to original sources

PubMed1993

Osteocalcin levels in maternal and cord blood.

OBJECTIVE: To measure osteocalcin levels in fetal and maternal blood. METHODS: Osteocalcin was measured by radioimmunoassay in paired maternal and umbilical venous and arterial blood obtained at term deliveries. RESULTS: Umbilical venous osteocalcin levels (mean +/- standard deviation) were significantly higher than arterial levels (10.28 +/- 4.99 versus 3.85 +/- 2.27 micrograms/L). Umbilical venous but not arterial levels of osteocalcin were significantly higher than maternal values (2.54 +/- 1.19 micrograms/L). CONCLUSION: Higher osteocalcin levels in umbilical venous blood than in umbilical arterial blood suggest that the placenta may be the main source of osteocalcin in late fetal life.

Female↗

PubMed1993

[A case of endodermal sinus tumor in the basal ganglia associated with Down's syndrome].

A case of Down's syndrome accompanied by endodermal sinus tumor of the left basal ganglia is reported. She was referred to us because of right hemiparesis. A CT scan showed a calcified mass in the left basal ganglia, which was well enhanced on contrast CT. Emergency removal of the tumor was performed because of its rapid growth, intratumoral hemorrhage, and acute hydrocephalus. The histological diagnosis established after surgery was endodermal sinus tumor. Alphafetoprotein-positive cells were seen in the resected tumor by light microscopy. Postoperative irradiation was very effective, and the high level of serum alphafetoprotein decreased during the course of irradiation. The residual tumor, enhanced on contrast CT, was treated by administration of cisplatin and etoposide after irradiation. Cases of malignant tumors other than leukemia, which are associated with Down's syndrome, are extremely rate. To our knowledge, including three cases of germ cell tumor, there have been only nine cases of brain tumors associated with Down's syndrome reported previously.

Adolescent↗

PubMed1993

[Interleukin-6 production in endometriosis].

The purpose of this study was to assess whether endometriotic implants of endometriosis could produce Interleukin (IL)-6. IL-6 was measured by means of an enzyme-linked immunosorbent assay (ELISA) in 21 patients with endometriosis of stage IV according to R-AFS classification of endometriosis. The tissues obtained from endometriotic implants were incubated for 24 hours and all their supernatants (n = 8) were positive for IL-6 and the mean level of IL-6 was approximately 30pg/ml per 1mg tissue dry weight. The level of IL-6 in the supernatant did not correlate with the serum estradiol level or with positivity against autoimmune antibodies in patients with endometriosis before surgery. The cultured stromal cells obtained from endometriotic implants were immunohistochemically positive for rabbit antihuman IL-6 polyclonal antibodies. IL-1 alpha (0.5ng/ml) and lipopolysaccharide (LPS) (10 micrograms/ml) caused a 50% and a 130% increase respectively, in IL-6 production in untreated cells (p < 0.01) of 24-hour culture (n = 3). On the other hand, estradiol, progesterone and danazol apparently had no effect on IL-6 production. The serum IL-6 levels of patients with myoma uteri (n = 10) were significantly (p < 0.05) enhanced after surgery, while those of patients with endometriosis (n = 14) declined after surgery. The anti IL-6 antibodies between 10ng/ml and 100ng/ml inhibited cell growth 20% (p < 0.05), while IL-1 alpha (0.5ng/ml) inhibited cell growth 50% (p < 0.01) in a 5 day cell culture (n = 6).(ABSTRACT TRUNCATED AT 250 WORDS)

Autoantibodies↗

PubMed1993

[Antitumor effect of PSK and its combined effect with CDDP on ovarian serous adenocarcinoma-bearing nude mice].

Although the antitumor effect of PSK can be increased by potentiating the immune functions of PSK in tumor-bearing hosts, the mechanisms of its action are not fully understood. In this study, we examined the antitumor effect and CDDP combined effect of oral administration of PSK on nude mice bearing a human ovarian cancer cell line (KF cells). 1. PSK was observed to have a significant antitumor effect in tumor-bearing nude mice and subsequently to bring about an increase in the survival rate and prolongation of the life span. 2. The antitumor effect of CDDP was (but not significantly) enhanced by oral administration of PSK and the prolongation of the life span of the tumor-bearing nude mice was obtained. 3. Six weeks after tumor inoculation, no significant natural killer (NK) cell activity in spleen cells from untreated nude mice was observed. However, when PSK (100 mg/kg but not 500 mg/kg) was given every other day, significant NK activity was induced. 4. The serum immunosuppressive acid protein (IAP) value in nude mice treated with PSK alone was significantly higher than that in nude mice treated with a combination of PSK (100 mg/kg) and CDDP. These results suggest that CDDP prevents the increase in serum IAP that occurs when PSK is used and that consequently combinations of PSK and CDDP result in augmentation of antitumor effects.

Animals↗

PubMed1992

[The effect of nicardipine on angiogenesis in vitro].

We studied the effect of nicardipine, a calcium channel blocker, on the morphological change of endothelial cells in vitro. Cultured endothelial cells derived from bovine carotid artery make tubular structures between collagen gel layers. Tube formation of endothelial cells was suppressed by culture with 10(-9)-10(-5) M of nicardipine in a dose dependent manner. Migration of endothelial cells was also suppressed by the same dose of nicardipine. However, proliferation of endothelial cells was not enhanced. These findings suggest that nicardipine acts as an inhibitor of angiogenesis in vitro by inhibiting the migration of endothelial cells.

Animals↗

PubMed1992

Adjuvant effects of antineoplastic prostaglandins to cisplatin in nude mice bearing human ovarian cancer cells.

Effects of antineoplastic prostaglandins (PG) on human ovarian cancer cell growth were examined by using HR cells derived from ascites of a patient with serous cystadenocarcinoma of the ovary. With regard to inhibition of cancer cell proliferation in vitro, the effects of delta 7-PGA1 was most marked, followed by that of delta 12-PGJ2, PGJ2 and PGD2. When antineoplastic prostaglandins were administered to nude mice bearing HR cells, tumor growth in groups treated with PGJ2 and delta 12-PGJ2 alone was significantly inhibited 63 days after tumor inoculation, compared to that in an untreated group. Consequently, a significant prolongation of median survival was obtained with delta 12-PGJ2, compared to that in untreated groups and in groups with cisplatin alone. In addition, when prostaglandins were administered together with cisplatin, adjuvant inhibitory effects on the tumor growth were obtained 35, 56 and 63 days after tumor inoculation. Subsequently a significant prolongation of median survival was observed when cisplatin was combined with PGD2 or delta 7-PGA1, compared to the results in groups treated with PGD2 alone, delta 7-PGA1 alone or cisplatin alone. Combination of PGJ2 or delta 12-PGJ2 and cisplatin resulted in a significant decrease of hematocrit and body weight 63 days after tumor inoculation, suggesting a deterioration of the median survival. These results suggest that combination of PGD2 or delta 7-PGA1 with cisplatin may be of clinical use for ovarian cancer resistant to cisplatin.

Animals↗

PubMed1992

Modulation of human lymphocyte response to phytohemagglutinin by antineoplastic prostaglandins.

The effects of antineoplstic prostaglandins (PGs) (PGE1, PGE2, PGA1, PGA2, delta 7-PGA1, PGD2, PGJ2 and delta 12-PGJ2) on human peripheral blood lymphocyte (PBL) responses to phytohemagglutinin (PHA) were studied in vitro. All PGs used in this study alone had no mitogenic effect on the PBL. The PBL response to PHA was significantly stimulated at low concentrations (10(-7) and 10(-8) M) of the PGE series while the high concentration (10(-5) M) markedly inhibited the PHA response. PGA1 and PGA2, metabolites of the PGE series, and also delta 7-PGA1 stimulated the PHA response in a dose-dependent manner between 10(-6) and 10(-8) M, and showed a significant stimulatory effect at 10(-6) M while significantly inhibiting the PHA response at 10(-5) M. Similarly, 10(-6) and 10(-7) M (but not 10(-8) M) of PGD2 stimulated significantly the PHA response. PGJ2 and delta 12-PGJ2, which are metabolites of PGD2, also stimulated the PHA response in a dose-dependent manner between 10(-6) and 10(-8) M, and had a significant stimulatory effect at 10(-6) and 10(-7) M. The degree of the stimulatory effect was most marked with the PGD2 series among the antineoplastic PGs examined in this study. On the other hand, PGs (PGF1 alpha and PGF2 alpha) having no antineoplastic effect did not show such effects on the PHA response. These results suggest that antineoplastic PGs may have immunoregulatory effects through negative and positive feedback.

Antineoplastic Agents↗

PubMed1992

Mother-to-infant transmission of hepatitis C virus.

Prospective studies of an infant of a mother infected with hepatitis C virus indicated that an HCV infection developed in the infant in early life. Perinatal transmission appeared to be the most likely explanation.

Female↗

PubMed1992

Insulin sensitivity during very-low-calorie diets assessed by minimal modeling.

The time course of plasma glucose, insulin, and C-peptide after intravenous glucose (300 mg/kg body wt) injection was analyzed with minimal model approach in nine normal females and seven obese females. Glucose tolerance, estimated by glucose assimilation coefficient (KG), was positively correlated with glucose effectiveness (SG), but not correlated with peripheral insulin sensitivity (SI) in obese females as well as normal females. These factors were estimated before and after weight loss with 1.8-MJ (420-kcal) very-low-calorie diets (VLCDs) or with 2.5-3.3-MJ (600-800-kcal) low-calorie diets in two obese subjects. KG and glucose effectiveness decreased after acute weight loss with VLCD, although insulin sensitivity increased. Weight loss with low calorie diets resulted in improvement of KG and glucose effectiveness. These results suggest that a significant amount of glucose is taken up through insulin-independent mechanisms during the intravenous glucose tolerance test (ivGTT) in these subjects. This insulin-independent glucose uptake may be an important determinant of the fate of glucose in obese females as well as normal females.

Blood Glucose↗

PubMed1992

The introduction of microvascular surgery to hepatic artery reconstruction in living-donor liver transplantation--its surgical advantages compared with conventional procedures.

Microvascular surgery for the reconstruction of the graft artery has been used since the 8th case in our series of 14 liver transplantations using living-related donors, and the clinical results have been compared between the first seven cases (the Loupe group) and the last seven cases (the Micro group). Seven arteries in 7 grafts were reconstructed with the use of loupe magnification in the Loupe group, while 8 arteries in 7 grafts were anastomosed with microscopic techniques in the Micro group. Statistically, there was no difference between the two groups in general background, including age, body weight and primary disease of the recipient, and in medical and surgical factors possibly relating to postoperative thrombosis of the hepatic artery. In two cases in the Loupe group, one or two additional reconstructions were necessary to obtain sufficient blood flow, while 8 arteries were anastomosed in the Micro group without any arterial complication in the postoperative period. There was no difference in time required for completing the arterial reconstruction (45.1 +/- 18.1 min in the Loupe versus 44.4 +/- 6.9 min in the Micro [mean +/- SEM]). Postoperative ultrasonic Doppler duplex study demonstrated a temporary decrease in the arterial flow in 2 cases of the Loupe group, and partial thrombosis of the artery was suspected. Additionally there were two episodes of hepatic artery thrombosis in 1 case of the Loupe group, in which emergent revision for thrombectomy and reanastomosis was performed at the first episode. This illustrated the higher incidence of arterial complications in the Loupe group compared with the Micro group (4 episodes/7 arteries in the Loupe versus 0/8 arteries in the Micro, P less than 0.05). In the present series there were no graft failures or arterial complications in the three deaths in the series. The clinical improvements achieved by microvascular surgery in living-donor liver transplantation suggest an alternative technical strategy for dealing with problematic arterial reconstruction in adult liver transplantation.

Child↗

PubMed1992

Leiomyosarcoma of the uterus: ultrasonography and serum lactate dehydrogenase level.

Between January 1, 1979, and September 30, 1990, a total of 1,886 patients in the National Defense Medical College Hospital, a self-referred population, had a hysterectomy because of signs and symptoms presumably resulting from uterine myomas. After hysterectomy with presumed benign disease, a histologic diagnosis of leiomyosarcoma was made in 7 patients (0.37%). Preoperative diagnosis of leiomyosarcoma was not made in any of the 7 patients. However, serum lactate dehydrogenase levels were abnormally elevated in 3 of them, and degenerative changes were found within the tumor by ultrasonography in 5 of them. Furthermore, increased lactate dehydrogenase levels and degenerative changes within the tumor were found in 3 of the patients whose tumors had 10 or more mitoses per 10 high-power fields. The prognosis for the leiomyosarcomas with increased mitotic rates is very poor. Therefore, a degenerative change within the uterine mass and an increased lactate dehydrogenase level, when present, should suggest the diagnosis of leiomyosarcoma.

Adult↗

PubMed1992

Effects of nicardipine on tube formation of bovine vascular endothelial cells in vitro.

BACKGROUND AND PURPOSE: The purpose of this study was to assess the effect of nicardipine, a Ca2+ channel blocker, on angiogenesis in vitro. METHODS: Bovine carotid artery endothelial cells were cultured between type I collagen gel layers with 10(-9) to 10(-5) M nicardipine. The morphological changes were monitored by phase-contrast microscopy and photographed. The total length of tubular structures was measured with an image analyzer system. Endothelial proliferation and migration assays were also performed with the same doses of nicardipine. RESULTS: Cultured endothelial cells form tubular structures between collagen gel layers. Tube formation of endothelial cells was suppressed by culture with 10(-9) to 10(-5) M nicardipine in a dose-dependent manner. Migration of endothelial cells was also suppressed by the same doses of nicardipine. However, proliferation of endothelial cells was not enhanced. CONCLUSIONS: Nicardipine acts as an inhibitor of angiogenesis in vitro by inhibiting the migration of endothelial cells. This result suggests that nicardipine may have therapeutic potential in angiogenic disorders such as tumor growth, atherogenesis, and diabetic retinopathy.

Animals↗

PubMed1992

Rapid morphological changes in bovine brain microvascular endothelial cells on extracellular matrices.

The morphological changes in endothelial cells derived from bovine brain microvasculature, carotid artery, and aorta during growth on extracellular matrices were compared. All cells formed tubular structures on a basement membrane. Ultrastructural studies showed that the tubular structures had lumens surrounded by many endothelial cells. On type I collagen gel, brain microvascular endothelial cells still formed tubular structures, but the other two cell types formed confluent monolayers. However, when a second layer of collagen gel was laid over these cells, tubular structures developed within 2-3 days. Brain microvascular endothelial cells form tubular structures more readily than endothelial cells derived from large vessels on both basement membrane and type I collagen gel.

Animals↗

PubMed1992

Pathogenic factors responsible for glucose intolerance in patients with NIDDM.

To define the pathogenic factors responsible for glucose intolerance in NIDDM, we estimated insulin secretory capacity, SI, and SG in 11 healthy, nondiabetic subjects and 9 NIDDM patients who had no SI impairment. All subjects studied were nonobese and normotensive. Each underwent a 75-g OGTT and a modified FSIGT: glucose was administered (300 mg/kg body weight), and insulin was infused (20 mU/kg over 5 min) from 20 to 25 min after the administration of glucose. SI and SG were estimated by Bergman's minimal-model method. The insulin response to oral glucose was significantly lower in NIDDM patients than in normal control subjects. First-phase insulin secretion expressed as the integrated area of plasma insulin above the basal level during the first 20 min was much smaller in NIDDM subjects (214 +/- 112 pM.min) than in control subjects (4643 +/- 885 pM.min, P < 0.01). SI was not statistically different in normal control subjects (1.27 +/- 0.18 x 10(-4) min-1.pM-1) versus diabetic patients (1.62 +/- 0.33 x 10(-4) min-1.pM-1). However, SG was significantly lower in diabetic subjects (1.11 +/- 0.17 x 10(-2) min-1) than in control subjects (2.35 +/- 0.26 x 10(-2) min-1, P < 0.01). These results suggest that impaired insulin secretion and decreased SG are the factors responsible for glucose intolerance of Japanese NIDDM patients with normal insulin sensitivity. Because SI and SG are the factors responsible for glucose intolerance of NIDDM patients with insulin resistance, it is conceivable that decreased SG is common in NIDDM patients regardless of their SI index.

Adult↗

PubMed1992

Effect of AT877 on cerebral vasospasm after aneurysmal subarachnoid hemorrhage. Results of a prospective placebo-controlled double-blind trial.

With the cooperation of 60 neurosurgical centers in Japan, a prospective randomized placebo-controlled double-blind trial of a new calcium antagonist AT877 (hexahydro-1-(5-isoquinolinesulfonyl)-1H-1,4-diazepine hydrochloride, or fasudil hydrochloride) was undertaken to determine the drug's effect on delayed cerebral vasospasm in patients with a ruptured cerebral aneurysm. A total of 276 patients, who underwent surgery within 3 days after subarachnoid hemorrhage (SAH) of Hunt and Hess Grades I to IV, were entered into the study. Nine patients were excluded because of protocol violation. The remaining 267 patients received either 30 mg AT877 or a placebo (saline) by intravenous injection over 30 minutes, three times a day for 14 days following surgery. Demographic and clinical data were well matched between the two groups. It was found that AT877 reduced angiographically demonstrable vasospasm by 38% (from 61% in the placebo group to 38% in the AT877 group, p = 0.0023), low-density regions on computerized tomography associated with vasospasm by 58% (from 38% to 16%, p = 0.0013), and symptomatic vasospasm by 30% (from 50% to 35%, p = 0.0247). Furthermore, AT877 reduced the number of patients with a poor clinical outcome associated with vasospasm (moderate disability or worse on the Glasgow Outcome Scale at 1 month after SAH) by 54% (from 26% to 12%, p = 0.0152). There were no serious adverse events reported in the AT877 group. This is the first report of a placebo-controlled double-blind trial that has demonstrated a significant reduction in angiographically revealed vasospasm by intravenous drug therapy.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗

PubMed1992

Saphenous vein graft to the distal vertebral artery between C-1 and C-2 using a lateral-anterior approach. Technical note.

The authors present a modified surgical procedure for extracranial vertebral artery reconstruction. The use of the proposed technique results in access to the V3 segment of the vertebral artery between the C-1 and C-2 vertebrae through the retrojugular space without requiring bone rongeuring. A saphenous vein bypass graft was placed between the common carotid artery and the V3 segment of the vertebral artery in three patients with bilateral occlusive lesions of the proximal vertebral arteries.

Cervical Vertebrae↗

PubMed1992

[Cytokinetic effects of cisplatin on cisplatin-resistant ovarian cancer cell lines].

Cytokinetic effects of cisplatin on human ovarian cancer cell lines with natural cisplatin-resistance was examined by means of flow cytometry. These ovarian cancer cell lines derived from patients with clear cell carcinoma and serous cystadenocarcinoma were established and designated "KK" and "MH", respectively. Both KK and MH cells have shown resistance to cisplatin and IC50 of them were 0.95 microM and 3.28 microM, respectively. Cisplatin inhibited cell cycle progression at G2 +M phase up to IC50 of each cell from the analysis of cell cycle. Similar results had been obtained in the case of "KF" cell which was sensitive to cisplatin. Further studies of these cells should be performed to elucidate the mechanism of cisplatin resistance.

Adenocarcinoma↗

PubMed1992

[Rapid morphogenesis of brain microvascular endothelial cells in culture system].

Endothelial cells of bovine brain microvascular vessels (BBECs), carotid artery (BCECs) and aorta (BAECs) were cultured on type I collagen and Matrigel. BBECs make tubular structures and BCECs and BAECs grow and make confluent monolayer on type I collagen gel. But BCECs and BAECs make tubular structures when second layer was overlaid. BBECs, BCECs and BAECs make tubular structures on Matrigel. These morphological changes were not affected by basic fibroblast growth factor. These results suggest that BBECs have more potent angiogenic ability than BCECs and BAECs.

Animals↗