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Biomedical subjects

S Tamai

Publications and source records attributed to S Tamai.

At least 271 records · Page 15Linked to original sources
PubMed1992

[A histopathological study on the femoral head necrosis in spontaneously hypertensive rats (SHR)].

The histopathological study was conducted in the femoral head of spontaneously hypertensive rats (SHR), which had frequently manifested osteonecrosis and a delay in the ossification at the femoral epiphysis. In order to elucidate the course of necrosis and its repair process, the bone dynamic of the femoral head was investigated with bone fluorochrome labelling technique. Femoral epiphyses in the SHR were classified into five groups, according to their histopathological changes in relation to osteonecrosis, its repair process and the delay in ossification. Changes in the growing rate of the growth plate at the femoral head and neck were measured quantitatively. As a result, the articular cartilage remained viable and overgrowing, while the epiphyseal plates were affected by the necrosis and there was early physeal maturation occurred. It is concluded that SHR appear to be a useful experimental model for Perthes' disease.

Animals↗
PubMed1991

In vitro uptake of bromodeoxyuridine by human hepatocellular carcinoma and its relation to histopathologic findings and biologic behavior.

The in vitro uptake of bromodeoxyuridine (BrdU) by hepatocellular carcinoma (HCC) cells was studied in 30 hepatectomized patients. Labeling of the nuclei by BrdU expressed as labeling index (LI) was 5.6 +/- 3.2% (mean +/- standard deviation), with a considerable variation from case to case. The mean LI in Grade III to IV cancers (less differentiated, by Edmondson and Steiner's classification, 11.1 +/- 2.1%) was significantly larger (P less than 0.001) than that in Grade I to II cancers (more differentiated, 4.5 +/- 2.0%). Capsule formation was found in all 17 patients except one (94%) with a low DNA synthetic HCC (LI less than 6.0%) compared with seven of 13 (54%) with a high DNA synthetic HCC (LI greater than or equal to 6.0%, P less than 0.02). The 2-year survival rate after surgery was significantly higher (P less than 0.02), and intrahepatic metastasis was significantly less (P less than 0.05) in the former group than in the latter. The BrdU LI of HCC tumors showed a strong correlation with histopathologic findings and the biologic behavior of HCC.

Adult↗
PubMed1991

Ultrastructural lipid and glycoconjugate cytochemistry of membranous lipodystrophy (Nasu-Hakola disease).

In order to assess the lipid and glycoconjugate characteristics of membranous lipodystrophy, a 29-year-old male with this disease was studied using an ultrastructural cytochemical approach. The specific membranocystic lesions of the disease are composed of cystic spaces and the lining membranes. The membranes were observed to have a two-layered character: microtubular structures in the layer adjacent to the spaces and a central amorphous zone. Lipid staining and the lipase digestion test revealed triglycerides localized not only in the cystic spaces but also in the microtubular structures. Lectin histochemical examination of carbohydrate components demonstrated that Maclura pomifera agglutinin bound strongly to the membranes, while Griffonia simplicifolia I, G. simplicifolia II, Concanavalia ensiformis and Triticum vulgaris agglutinin reacted weakly. Our results indicate the presence of triglycerides and carbohydrates with mainly alpha-D-galactose residues in the distinctive membranocystic lesions, in particular in the microtubular structures.

Adult↗
PubMed1991

Continuous local intra-arterial infusion of antithrombotic agents for replantation (comparison with intravenous infusion).

The success rate of replantation of amputated digits and limbs appears to be improved by local continuous intra-arterial infusion of urokinases, heparin and PGE1 at a daily dose of 240,000 I.U., 10,000 U, and 40 micrograms, respectively, for ten days, in comparison to intravenous infusion of the drugs. The purpose of this study was to investigate the difference between the haematological effects of intra-arterial and intravenous infusion. Accordingly coagulation and fibrinolytic enzyme levels were examined before, and at 4 and 12 hours after the start of infusion and on the 3rd and 10th postoperative days. Intra-arterial infusion was advantageous over intravenous infusion probably because the effect of general metabolism on drug levels was small, drugs exhibited immediate action and efficacy was localised. No particular side effects were demonstrated.

Blood Coagulation Factors↗
PubMed1991

The sliding venous flap for covering skin defects with poor blood supply on the lateral aspects of fingers.

For the treatment of skin defects with poor blood supply on the lateral aspects of the fingers, particularly the radial side of the index finger and the ulnar side of the little finger which have been difficult to cover conventionally, we have developed the sliding venous flap. The flap can be moved by using the "sag" obtained from the dissected dorsal veins of the same finger. We have applied this technique in six cases with excellent results. The indications are limited to cases with only slight crushing of the dorsum of the finger. We consider this technique safe and effective in covering skin defects with poor blood supply on the lateral aspects of fingers.

Adolescent↗
PubMed1991

Increased uptake of bromodeoxyuridine by hepatocytes from early stage of primary biliary cirrhosis.

The relationship between DNA synthesis activities of hepatocytes in biopsied specimens and liver volume was studied in various stages of primary biliary cirrhosis using an in vitro bromodeoxyuridine (a thymidine analogue)-anti-bromodeoxyuridine reaction and computed tomography. The mean bromodeoxyuridine (+/- SE) labeling index for 10 patients in an early histological stage (stage I, 4, and stage II, 6, 3.4% +/- 0.4%) of primary biliary cirrhosis was 17 times that for 6 control subjects (0.2% +/- 0.1%, P less than 0.001), and was significantly higher than that for 19 female patients with chronic aggressive hepatitis (0.9% +/- 0.2%, P less than 0.001), 14 compensated cirrhotic patients of viral origin (all female, 1.1% +/- 0.3%, P less than 0.01), and 5 patients with stage III primary biliary cirrhosis (0.5% +/- 0.1%, P less than 0.001). The mean (+/- SE) liver volume in the early stage of primary biliary cirrhosis (1225 +/- 40 cm3) was about 1.5 times that in control subjects (835 +/- 42 cm3, P less than 0.001). These results suggest that liver volume has already become large in the early stage of primary biliary cirrhosis perhaps because of markedly increased DNA synthesis in hepatocytes.

Adult↗
PubMed1991

Bonding osteogenesis in coralline hydroxyapatite combined with bone marrow cells.

Coralline hydroxyapatite ceramics alone (control) and the ceramics combined with rat marrow cells were implanted subcutaneously in the backs of syngeneic Fischer rats and harvested at 1,2,3,4,6,8 and 24 wk after surgery. None of the control ceramics (without marrow) showed bone formation. However, ceramics combined with marrow cells showed consistent new bone formation in the pore regions. Histometrical results revealed increased new bone formation over time. Undecalcified sections of the ceramics studied by fluorochrome labelling showed that the osteogenesis began directly on the surface of the ceramic and proceeded centripetally towards the centre of the pores (bonding osteogenesis). SEM-EPMA analysis of the bone-ceramic interface also revealed direct bonding of bone to the ceramic surface.

Animals↗
PubMed1991

Arthroscopic meniscal repair with fibrin glue.

Since 1984 we have arthroscopically repaired 40 meniscal tears in 32 patients using fibrin glue in our operative technique. This technique was reported initially in 1985 (Ishimura M, Samma M, Habata T, Fujisawa Y. The use of fibrin glue for fresh knee injury. Cent Jpn Orthop Traumat 1985; 28:1404-8), with a more detailed study published in 1987 [Ishimura M, Samma M, Fujisawa Y, et al. Arthroscopic repair of the meniscus tears with fibrin glue. Arthroscopy (Jpn) 1987;12:31-6]. During the follow-up period, which ranged from 10 months to 6 years and 7 months (mean: 3 years and 8 months), only two patients complained of meniscal symptoms and underwent arthroscopic partial meniscectomy. Twenty patients with 25 repairs underwent repeat arthroscopy at an average of 5.7 months (range: 2 months-1 year and 2 months) after the initial repair. Twenty repairs were rated as good, four as fair, and one as poor by arthroscopic evaluation criteria. At present, the most appropriate use of this arthroscopic meniscal gluing technique is in tears in the posterior segment, which are difficult to suture without arthrotomy. Even a long tear with a stable reduced position can be expected to show good healing. When reduction of the tear is not stable, additional sutures should be used.

Adolescent↗
PubMed1991

Metastatic potential of malignant fibrous histiocytoma of myxoid or giant-cell subtype in rats.

We have previously reported on the induction of rat malignant fibrous histiocytomas by 4-hydroxiaminoquinoline 1-oxide. The present study describes cell number- and time-related formation of metastatic lung nodules after i.v. injection of cell suspensions containing various numbers (10(3) to 10(5)/ml) of myxoid or giant-cell subtype malignant fibrous histiocytoma cells. The metastatic potential of the myxoid subtype of rat malignant fibrous histiocytoma was significantly enhanced by i.v. injection of tumor cells selected from metastatic lung nodules and was further increased by repeating the selection procedure more than 7 times. In contrast, the growth activity of subcutaneous transplants of tumor fragments obtained from metastatic lung nodules derived from myxoid subtype did not differ from that of parent malignant fibrous histiocytomas.

4-Hydroxyaminoquinoline-1-oxide↗
PubMed1991

An investigation of venous pressure and oxygen tension in human extremities: an experimental study of survival in pedicled venous flaps.

The pedicled venous flap is used at various sites, such as the finger, forearm, and leg. The authors previously reported that the reasons for the viability of such flaps, based on the digital dorsal vein and used for repairing digital skin defects in the earlier study, were high venous pressure or oxygen tension, as well as the possible effects of plasmatic imbibition and outflow through the draining vein. To investigate the importance of venous pressure and oxygen tension in the survival of these flaps at other sites in the body, measurements were made comparing these parameters in the digital vein, cephalic vein, and greater saphenous vein, which are all used clinically as draining veins in pedicled venous flaps. Although measurements in other sites were consistently lower than in the digital dorsal vein, since these other venous flaps are nevertheless viable in the clinical situation, their viability may not be due only to relatively high venous pressure and oxygen tension. The authors intend to carry out further comparative studies on plasmatic imbibition in the flap and outflow through the draining vein.

Adolescent↗
PubMed1991

Combined therapy with antithrombotic agents and radical scavengers for reperfusion injury of flaps.

The usefulness of combining antithrombotic agents and radical scavengers in the treatment of reperfusion injury (an almost ideal approach) was substantiated using an ischemic flap model. The cause(s) of reperfusion injury was hypothesized on the basis of differences in effects between antithrombotic agents and radical scavengers in the experimental groups. Flap specimens were also obtained regularly for histologic examination. The experiment was conducted in nine rabbit groups. For continuous treatment with intraarterial antithrombotic agents, both heparin and urokinase were continuously injected at respective administration rates of 20 U/kg/hr and 200 IU/kg/hr for seven consecutive days immediately before reperfusion. For intraarterial radical scavenger treatment, a solution of both 30,000 U/kg SOD and 30,000 U/kg catalase in 5 ml of a lactated Ringer's solution was injected over a period of about 30 min immediately before reperfusion. The ischemic time of the flaps was 10 hr for Group I and 12 hr for Group II. Each group was comprised of subgroups a, b, c, and d: a = control; b = continuous intraarterial antithrombotic agent injection; c = intraarterial lactated Ringer's solution alone; and d = intraarterial radical scavenger injection. For Group II, an additional subgroup e was established, which received continuous injection of both intraarterial antithrombotic agents and injected intraarterial radical scavenger. In the 10-hr ischemic treatment group, an effect was obtained by continuous intraarterial antithrombotic agents alone. In the 12-hr ischemic treatment group, a significant improvement in flap-take ratio was obtained using intraarterial radical scavenger, in combination with antithrombotic agents. Observation of the flaps that survived in subgroups Ib and IIe revealed skin thinning, vascular wall thickening, and muscular tissue degeneration, although the skin architecture was well preserved.

Animals↗
PubMed1991

Comparison between sevoflurane and halothane for paediatric ambulatory anaesthesia.

We have compared the rapidity and quality of recovery after sevoflurane anaesthesia with those after halothane anaesthesia. Thirty unpremedicated paediatric outpatients undergoing pulsed-dye laser therapy for port-wine stains were allocated randomly to receive either halothane or sevoflurane anaesthesia. Each group received 60% nitrous oxide and 1.0-1.5 MAC of volatile agent in oxygen for approximately 40 min. Patients receiving sevoflurane exhibited more rapid emergence and a significantly shorter postoperative recovery time compared with those receiving halothane. No major adverse effects were encountered in each group. These results suggest that sevoflurane anaesthesia is preferable to halothane anaesthesia for paediatric ambulatory patients.

Ambulatory Surgical Procedures↗
PubMed1991

Evidence of sex difference in DNA synthesis in hepatocellular carcinoma.

To clarify sex differences in DNA synthesis in hepatocellular carcinoma (HCC), bromodeoxyuridine labeling indices (BrdU LI) of HCC cells included in tumor biopsy specimens from 12 consecutive male patients and from 5 consecutive female patients all with liver cirrhosis and HCC were examined using an in vitro labeling technique. The mean BrdU LI +/- SE of HCC from male patients (7.7 +/- 0.8%) was significantly (P less than 0.05) higher than that from female patients (4.4 +/- 1.0%). While 7 of the 12 male HCC patients belonged to the high DNA synthesis group (BrdU LI greater than or equal to 7.0%), none of the 5 female HCC patients showed high DNA synthesis (P less than 0.05). We conclude that DNA synthesis in HCC was higher in males than in females.

Aged↗
PubMed1991

Intramedullary multiple hematomas in siblings with congenital alpha-2-plasmin inhibitor deficiency: orthopedic surgery with protection by tranexamic acid.

Congenital alpha 2-plasmin inhibitor deficiency is very rare, but causes bleeding problems similar to hemophilia. Three young Japanese sisters affected with congenital alpha 2-plasmin inhibitor deficiency have been reported by us earlier. Recently we encountered a particular form of intramedullary multiple hematomas in the long bones in all of them which was not reported previously. In 2 of the sisters orthopedic operations were successfully performed by using an antiplasmin reagent: tranexamic acid. In this paper we describe the characteristics of the hematomas and the hemostatic management with tranexamic acid.

Adolescent↗
PubMed1991

Biphasic changes in hypothalamo-pituitary-adrenal function during the early recovery period after major abdominal surgery.

Regulatory mechanisms of the hypothalamo-pituitary-adrenal (H-P-A) axis during and after major abdominal surgery were studied in a group of patients who underwent upper abdominal surgery. We first examined the general profile of the changes of the H-P-A axis from the day before surgery to the seventh day after surgery. On the day of surgery, plasma levels of CRH, ACTH, and cortisol were all significantly elevated after skin incision (phase I). During the next 2 days, plasma cortisol levels remained significantly elevated, and the both plasma CRH and ACTH levels were suppressed below the control levels obtained on the day before surgery (phase II). Several additional studies, carried out to analyze the mechanism that maintains the high plasma cortisol levels, revealed the following features of the H-P-A axis during phase II. Plasma free cortisol levels in this phase were higher than those during the preoperative period. The exogenously administered hydrocortisone clearance rate in phase II did not differ from that observed on the day before surgery. Dexamethasone administration resulted in a decrease in plasma cortisol levels similar to that observed preoperatively. Conversely, the ACTH-stimulated cortisol increase was significantly greater in phase II than that observed preoperatively. These results suggest that during and after major surgical stress, the H-P-A axis undergoes a biphasic change in the pattern of the stress response and during the second phase, not the continuous hypothalamo-pituitary drive but the increased adrenal responsiveness to ACTH is responsible at least in part for maintaining the elevated plasma cortisol level.

Abdomen↗
PubMed1991

Self-association of telomeric short oligodeoxyribonucleotides containing a dG cluster.

Oligonucleotides containing a dG cluster, d(TmGnTm), are models of single-stranded parts of telomeric deoxyribonucleic acid and substitutes for poly(dG). Electrophoretic and spectroscopic analyses of the oligomers indicate that the oligomers can form two alternative structures, single- and quadruple-stranded helices, in solution at room temperature. The transformation of the single-strandef form into the quadruple-stranded form or vice versa is undetectable in 0.1 M NaCl at 4.3 x 10(-5) M strand concentration at room temperature. However, at a 50-fold higher strand concentration, the single-stranded oligomer is gradually converted into the quadruplex. An increase in ionic strength stabilizes the single-stranded structure, so it seems to inhibit the formation of the quadruplex. The quadruplex, [d(TTGGGGTT)]4, is resistant to denaturation in 7 M urea, in which the Watson-Crick type d(TTGGGGTT).d(AACCCCAA) duplex dissociates. An increase in the number of T residues facilitates the dissociation of the quadruplex by heating. Thus the number of T residues surrounding the dG cluster might control the rigidity of the quadruplex structure.

Animals↗
PubMed1991

Tarsal tunnel syndrome. Causes and results of operative treatment.

From 1975 to 1988, operative treatment was performed on 50 feet in 45 patients with tarsal tunnel syndrome. The causes of this syndrome were correlated with operative findings and included ganglia in 18, and a bony prominence from talocalcaneal coalition in 15. Five feet had sustained an injury, tumours were found in three and there was no obvious cause in nine. In most cases in need of operative treatment, there was a space-occupying lesion. Classifying the results according to causes, those with coalition or a tumour fared better, and idiopathic and traumatic cases had a worse outcome. In cases with a definite lesion, an excellent result can be expected from surgical treatment carried out soon after onset of the condition.

Adolescent↗