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Biomedical subjects

S Tamai

Publications and source records attributed to S Tamai.

At least 55 records · Page 3Linked to original sources
PubMed2000

Close association between high serum ALT and more rapid recurrence of hepatocellular carcinoma in hepatectomized patients with HCV-associated liver cirrhosis and hepatocellular carcinoma.

We investigated whether or not a high serum alanine aminotransferase (ALT) level is associated with a more rapid recurrence of hepatocellular carcinoma (HCC) in hepatectomized patients with hepatitis C virus (HCV)-associated liver cirrhosis (LC) (HCV-LC) and HCC. Thirty-three hepatectomized patients with HCV-LC and HCC of a single nodule who had no histologic evidence of portal or hepatic vein invasion and who had been followed up for more than 3 years were included in the study. They were subdivided into two groups according to their serum ALT levels, ALT being a well-known marker of inflammatory necrosis in the liver. Seventeen patients whose serum ALT levels showed several peaks or plateaus above 80 international units (IU) were designated as the high ALT group, and 16 patients whose serum ALT levels showed a sustained low level below 80 IU until the first recurrence were designated as the low ALT group, and the interval between hepatectomy and the first recurrence was observed. In the high ALT group, HCC recurred within 3 years in 70.6% of the patients. In contrast, it recurred in only 18.8% of the low ALT group within the same period (p < 0.05). There was a significant difference (p = 0.0201) between the two groups in the cumulative nonrecurrence rate. The mean interval in recurrent patients between hepatectomy and the first recurrence in the high ALT group (23.6 +/- 2.8 months; mean +/- SE) was significantly (p < 0.02) shorter than that in the low ALT group (49.3 +/- 9.7 months). The expected interval between hepatectomy and recurrence was as short as 2.8 +/- 0.5 years (mean +/- SE) in the high ALT group, compared with 5.8 +/- 0.7 years in the low ALT group (p < 0.05). These results showed that the recurrence of HCC was accelerated in the high ALT group, suggesting that suppression of the rise in ALT level after hepatectomy by treatment with anti-inflammatory drugs may prolong the interval until recurrence by about 2 years in hepatectomized patients with HCC and HCV-LC.

Aged↗
PubMed2000

In vivo osteogenic capability of cultured allogeneic bone in porous hydroxyapatite: immunosuppressive and osteogenic potential of FK506 in vivo.

Fischer or ACI rat marrow cells were obtained from femoral shafts and were cultured to confluence in Eagle's minimal essential medium (EMEM) supplemented with 15% fetal bovine serum. After trypsinization, the cells were subcultured on porous hydroxyapatite (HA; Interpore 500) blocks in the presence of beta-glycerophosphate and 10 nM dexamethasone (Dex). After 2 weeks of subculture, a mineralized bone matrix with osteogenic cells developed on the HA pore surfaces. ACI or Fischer cultured bone tissue/HA constructs were implanted subcutaneously into the backs of Fischer rats and the immunosuppressant FK506 was given to the rats for 4 weeks. Implants were harvested 4 weeks and 8 weeks after insertion. At 4 weeks, the ACI constructs (allografts) showed high levels of osteogenic parameters (alkaline phosphatase [ALP] activity and osteocalcin content) and bone formation was observed together with active osteoblasts without obvious accumulation of inflammatory cells. At 8 weeks, active osteoblasts and progressive bone formation were still observed, while osteogenic parameters remained high and osteocalcin messenger RNA (mRNA) was detected. Without FK506 administration, the allografts showed neither bone formation nor osteocalcin mRNA and there were only trace levels of the osteogenic parameters. In the case of Fischer constructs (isografts), extensive bone formation was detected and all the osteogenic parameters were higher with FK506 than without FK506 at both 4 weeks and 8 weeks. These results indicate that cultured bone tissue/HA constructs possess a high osteogenic potential, even as allografts, and that FK506 not only has an immunosuppressive action, but also promotes bone formation.

Alkaline Phosphatase↗
PubMed2000

Treatment of extrinsic flexion deformity of the toes associated with previous removal of a vascularized fibular graft.

BACKGROUND: Complications from vascularized fibular bone-grafting are infrequent. We saw six patients who had a painful flexion deformity of the great and lesser toes after a free vascularized fibular graft had been obtained from the ipsilateral leg. In this report, we discuss our management of these patients. METHODS: Painful flexion deformity of the toes that had developed in six adults after removal of a free vascularized fibular graft was treated by cutting of the flexor hallucis longus alone in three patients, by lengthening of the flexor hallucis longus alone in one, and by cutting of both the flexor hallucis longus and the flexor digitorum longus in two. RESULTS: After an average duration of follow-up of six years and eleven months, the flexion deformity of the great and lesser toes had decreased or disappeared, leading to improved or full extension of the digits. Preoperative and postoperative measurements of muscle strength for plantar flexion of the interphalangeal joints did not change appreciably. CONCLUSIONS: Cutting or lengthening of the flexor hallucis longus behind the ankle provides an adequate release of digital flexion deformities that occur after removal of a vascularized fibular bone graft.

Adult↗
PubMed2000

Effect of alcohol intake on the levels of plasma homocysteine in healthy males.

Hyperhomocysteinemia in chronic alcoholics has been reported, but it remains unclear whether relatively low alcohol intake compared with the previous reports affects the plasma homocysteine level. To investigate this issue, we performed two studies, a population-based study and an alcohol withdrawal study. An analysis of plasma homocysteine levels in a population of 236 healthy males showed no significant association between alcohol consumption and other tested parameters. In the withdrawal study, the subjects with a history of daily alcohol consumption (81.8 +/- 33.0 g/d, mean +/- SD, 40-150g/d, range) abstained from alcohol for 4 wk. After withdrawal, the levels of serum gamma-glutamyl transpeptidase, aspartate aminotransferase, triglycerides, and high-density lipoprotein cholesterol significantly decreased, but the plasma homocysteine level did not change. These results suggest that alcohol intake, at least as far as the amount of beverages our study subjects consumed, has no effect on the plasma homocysteine level in healthy males.

Adult↗
PubMed1999

Association between high serum alanine aminotransferase levels and more rapid development and higher rate of incidence of hepatocellular carcinoma in patients with hepatitis C virus-associated cirrhosis.

BACKGROUND: Many studies have demonstrated in animal experiments that persistent inflammation may accelerate the development of carcinoma. In this article, the question of whether the persistent elevation of serum alanine aminotransferase (ALT) levels (which represents the inflammatory necrosis of hepatocytes) correlates with the development of hepatocellular carcinoma (HCC) was studied in patients with early stage hepatitis C virus (HCV)-associated cirrhosis. METHODS: Sixty-nine consecutive patients with biopsy proven HCV-associated cirrhosis (mostly Child's Stage A) who had been followed for >5 years for the development of HCC were studied. They were subdivided into 3 groups according to their serum ALT levels: Group A was comprised of 28 patients whose annual average serum ALT level was persistently high (>/= 80 IU) (high ALT group), Group B was comprised of 28 patients whose annual average serum ALT level was persistently low (< 80 IU) (low ALT group), and Group C was comprised of 13 unclassified patients. The patients had been studied prospectively with frequent ultrasonography and magnetic resonance imaging or computed tomography for > 5 years. RESULTS: In the high ALT group HCC developed in 71.4% of patients compared with 25.0% in the low ALT group over the observation period (P < 0.005). The 5-year rate of incidence of HCC in the high ALT group was as high as 53.6% compared with only 7.1% in the low ALT group (P < 0.001). The expected interval between the diagnosis of cirrhosis and the development of HCC was 6.0 +/- 0.7 years (mean +/- standard error) in the high ALT group and 12.7 +/- 1.2 years in the low ALT group (P < 0.001). CONCLUSIONS: The results of the current study demonstrated that the development of HCC was more rapid in the high ALT group with HCV-associated cirrhosis.

Aged↗
PubMed1999

Overexpression of matrix metalloproteinase (MMP)-9 correlates with metastatic potency of spontaneous and 4-hydroxyaminoquinoline 1-oxide (4-HAQO)-induced transplantable osteosarcomas in rats.

In the present experiment, the expression of matrix metalloproteinase (MMP)-2 and MMP-9, key proteins in the MMP family, and the tissue inhibitors of metalloproteinase (TIMP)-1 and TIMP-2, antagonistic proteins against MMP-2 and MMP-9, respectively, were investigated by Northern blot analysis in rat transplantable osteosarcomas with high and low metastatic potencies. Two transplantable osteosarcomas, one induced with the carcinogen, 4-hydroxyaminoquinoline 1-oxide (4-HAQO) (COS, chemical carcinogen-induced osteosarcoma), and the other, a spontaneous lesion (SOS, spontaneous osteosarcoma), were repeatedly transplanted from lung nodules to generate lines with high metastatic potency, C-SLM (chemical carcinogen-induced osteosarcoma, selected lung metastatic lesions) and S-SLM (spontaneous osteosarcoma, selected lung metastatic lesions), respectively. MMP-9 was overexpressed in both S-SLM and C-SLM, and TIMP-2 in the case of S-SLM. Neither MMP-2 nor TIMP-1 was overexpressed in either of the transplantable osteosarcomas with high metastatic potentials. The active form MMP-9, studied by zymography, increased in S-SLM and C-SLM but not in SOS and COS. MMP-9 mRNA expression was highly correlated with the gelatinolytic activity of active form MMP-9 (r = 0.85, P < 0.0001) and with the activation ratio of MMP-9 (r = 0.83, P < 0.0001). However, the active form MMP-2 was not detectable in all cases. These results suggest that overexpression of MMP-9 mRNA is one of the essential factors in the acquisition of metastatic potential in rat transplantable osteosarcomas.

4-Hydroxyaminoquinoline-1-oxide↗
PubMed1999

Al2O3 doped apatite-wollastonite containing glass ceramic provokes osteogenic differentiation of marrow stromal stem cells.

Fresh marrow cells were obtained from femora of Fischer rats and cultured in a medium containing 15% fetal calf serum (FCS) until confluence. After trypsinization, cells were subcultured at a cell density of 100 x 10(3)/35-mm well in the presence of FCS, beta-glycerophosphate, and ascorbic acid phosphate on four different culture substrata. The period of subculture was 2 weeks; the substrata used were the culture dish, apatite-wollastonite containing glass ceramic (AW), hydroxyapatite coated AW (HA/AW), and Al2O3 doped AW (Al/AW). The HA coating was attained by the incubation of AW in simulated physiological solution. The glass matrix of AW and HA/AW contained MgO, CaO, P2O5, and SiO2; Al/AW contained Al2O3 in addition to these components. The subculture on Al/AW substratum showed many alkaline phosphatase (ALP) positive nodules and the highest ALP activity. On a Northern blot analysis the housekeeping gene of beta-actin mRNA was evenly detected from the cells cultured on all substrata; however, bone-specific osteocalcin mRNA was only detected from the cells on Al/AW. These results indicate that Al/AW provokes the osteoblastic differentiation of marrow stromal stem cells.

Alkaline Phosphatase↗
PubMed1999

Postoperative complications in patients of esophageal cancer after neoadjuvant chemotherapy.

We examined the effects of neoadjuvant chemotherapy on surgery by evaluating postoperative complications in 50 patients who had undergone neoadjuvant chemotherapy (Group A) and in 108 patients who had undergone surgery without neoadjuvant chemotherapy (Group B). Toxicity of grade 3 by chemotherapy were WBC in 3 patients (6%), alopecia in 3 patients (6%), and anorexia in 22 patients (44%). There were 4 patients with anastomotic leakage (8%) (all in minor), 5 patients with infection of wound (10%), 6 patients with arrhythmia (12%), no patients with postoperative bleeding, 2 patients with respiratory complications (4%), and no patients who died due to complications in Group A. In Group B, there were 13 patients with anastomotic leakage (13%) (all in minor), 12 patients with infection of the wound (11%), 11 patients with arrhythmia (10%), 2 patients with postoperative bleeding (2%), 8 patients with respiratory complications (7%), and 2 patients who died due to complications (2%). There was no significant difference in the incidence of postoperative complications between the patients who had undergone surgery after neoadjuvant chemotherapy, such as CDDP + 5FU therapy and FAP therapy, and the patients who had undergone surgery without neoadjuvant chemotherapy, in patients who had been diagnosed as being able to undergo relative non-curative resection or better, who had Ccr 60 ml/min or more and no severe complication, and whose stomach could be used for reconstruction of the esophagus, on the condition that surgery would be performed on NC patients at the end of first-course treatment.

Alopecia↗
PubMed1999

Treatment with a gonadotropin-releasing-hormone analog and attainment of full height potential in a male monozygotic twin with gonadotropin-releasing hormone-dependent precocious puberty.

UNLABELLED: We report on a pair of male monozygotic twins, one unaffected and the other affected with gonadotropin-releasing hormone (GnRH)-dependent precocious puberty, and discuss the role of treatment with a GnRH analog in the attainment of full height potential in GnRH-dependent precocious puberty. At 1.6 years of age, the affected twin was studied for tall stature (+3.8 SD), and was diagnosed as having GnRH-dependent precocious puberty due to a hypothalamic hamartoma of the tuber cinereum. He was treated with oral cyproterone acetate (110-170 mg/m(2) daily) from 1.8 through 5. 0 years of age, with oral cyproterone acetate and intranasal buserelin acetate (700-900 microg/m(2) daily) from 5.0 through 7.5 years, and with intranasal buserelin acetate alone (1100- 1400 microg/m(2) daily) from 7.5 through 12.6 years. He attained a final height of 171.0 cm at 14.9 years of age (+0.10 SD) and his twin 170. 0 cm at 15.3 years of age (-0.10 SD), with their target height being 174.5 +/- 9.0 cm. CONCLUSION: This study indicates that GnRH analog treatment may preserve near full height potential in some patients with GnRH-dependent precocious puberty.

Administration, Inhalation↗
PubMed1999

Neurohistology of the sinus tarsi and sinus tarsi syndrome.

The purpose of this study was to clarify the neural anatomy of the sinus tarsi. The nerve endings of the synovium in the sinus tarsi were examined. The synovial membrane in the sinus tarsi was excised in 20 patients with sinus tarsi syndrome (20 feet) and in 2 feet from subjects without symptoms (controls). In 15 of the 20 patients and the two controls, the excised synovial membrane was studied histologically with staining by a modified Gairns gold chloride method. Numerous neural elements were observed in the sinus tarsi in all examined synovium. There were abundant free nerve endings and three types of mechanoreceptors: Pacinian corpuscles, Golgi corpuscles, and Ruffini corpuscles. Macroscopic observation and histological examination, using hematoxylin and eosin, in the other 5 patients revealed chronic synovitis in the sinus tarsi. Our findings suggest that the sinus tarsi is not only a talocalcaneal joint space but a source of nociceptive and proprioceptive information on the movement of the foot and ankle. Sinus tarsi syndrome may result from disorders of nociception and proprioception in the foot.

Adolescent↗
PubMed1999

Sleep complaints among the elderly: results from a survey in a psychogeriatric outpatient clinic in Brazil.

BACKGROUND: Sleep complaints are frequent in old age. These difficulties are often associated with health-related problems, drug consumption, and the presence of mental disorders. Nonetheless, only sparse information is available on the clinical characteristics of elderly persons with insomnia. AIMS: (a) To evaluate the prevalence of sleep problems among the elderly assessed in a psychogeriatric outpatient clinic; (b) to evaluate the association between the use of sleep tablets and sleep difficulties in this sample of patients. METHODS: One hundred eighteen consecutive subjects were recruited from a psychogeriatric outpatient service in São Paulo, Brazil. Their sleep pattern was systematically assessed with the "sleep inventory," a questionnaire consisting of 31 items that evaluate a number of sleep-related features. Clinical diagnoses followed the ICD-10 clinical descriptions and diagnostic guidelines. The number of drugs consumed by patients was also recorded. RESULTS: Sleep complaints were highly prevalent (59.3%), with early-morning awakening and nightmares being more frequent among patients with a depressive disorder. The use of sleep tablets was reported by 37.3% of subjects, and was associated with subjective sleep difficulties (odds ratio [OR] = 7.13, p = .008), difficulties falling asleep (OR = 7.33, p = .021), and frequent awakening during the night (OR = 7.10, p = .040) in a logistic regression analysis. CONCLUSION: Sleep dissatisfaction is frequent among psychogeriatric outpatients. Subjects taking hypnotic drugs have more sleep-related complaints than those who do not. The clinical use of hypnotics may not be very effective for the treatment of sleep-related problems in the elderly. There is an urgent need for systematic prospective controlled studies to assess the efficacy and safety of the various forms of treatment of insomnia in old age.

Aged↗
PubMed1999

Delay in administration of CDDP until completion of AGM-1470 treatment enhances antimetastatic and antitumor effects.

The efficacy of cis-diammine dichloroplatinum (CDDP) therapy in combination with continuous administration of angiogenesis inhibitor o-(chloroacetyl-carbamoyl) fumagillol (AGM-1470) was evaluated experimentally using a transplantable rat osteosarcoma line previously established in our laboratory. AGM-1470 (2.5 mg/kg body weight/week) was administered by Alzet osmotic pumps for 2 weeks starting from 7 days after tumor inplantation and CDDP (1.25 mg/kg) was given on days 21 and 24. The number of lung metastatic nodules was counted and the wet weights of the primary tumors were measured 5 weeks after tumor inplantation. Values with administration of CDDP 3 days after discontinuation of AGM-1470 were significantly lower than when the two agents were coadministered (P < 0.05). This animal model should facilitate optimization of the timing of combination therapy.

Animals↗
PubMed1999

Clear cell change in colorectal adenomas: its incidence and histological characteristics.

AIMS: The aim of our investigation was to clarify the histological characteristics and biological significance of clear cell change in colorectal adenomas. METHODS ANID RESULTS: We found three cases (0.086%) of tubular adenomas with clear cell change in a review of 3486 cases of colorectal adenoma. These three cases occurred in male patients and were located in the left-sided colon. To investigate the nature and biological significance of the clear cells, we conducted histochemical staining (periodic acid-Schiff (PAS) with or without diastase digestion, alcian blue pH 2.5) and immunohistochemical staining (using antibodies against carcinoembryonic antigen (CEA), alpha-fetoprotein, p53 protein and Ki67 antigen) and also mitotic counts. Histologically, the changed area was characterized by pyknotic and randomly arranged nuclei with PAS-negative clear and vacuolated cytoplasm. Immunoreactivity for CEA was diffuse and strong in the clear cells, but not in the tumour cells in the ordinary portion of the adenomas. The Ki67 labelling index and the mitotic activity were both higher in the clear cell portion than in the ordinary portion. CONCLUSIONS: This is the first study to indicate the incidence of clear cell change among colorectal adenomas. It has confirmed high proliferative activity within the clear cell portion of colorectal adenomas.

Adenoma↗
PubMed1999

Osteocutaneous radial forearm flap for hand reconstruction.

We treated 5 patients (4 men and 1 woman) with bone and soft tissue defects or total thumb loss using an osteocutaneous radial forearm flap. Their ages at the time of surgery ranged from 27 to 65 years (mean, 53 years). Preoperative conditions were traumatic loss of the thumb in 3 cases and severe injuries with soft tissue and bone defects in 2. The length of the donated radius ranged from 2 to 7 cm (mean, 4.7 cm). In 4 patients the radial forearm flap was transposed, including the lateral antebrachial cutaneous nerve as a sensory flap. Simultaneous iliac bone grafting to the donor site was also performed in 4 of the cases. The follow-up period ranged from 44 to 87 months (mean, 64 months). All flaps survived over their full extent. Radiographic bone union was attained after 2 to 3 months (mean, 2.5 months). Two-point discrimination over the 4 sensory flaps ranged from 8 to 15 mm (mean, 10.8 mm). No radius fractures occurred. No patients showed signs of vascular insufficiency from sacrifice of the radial artery. The radial forearm flap provides thin skin of good texture together with bone for a 1-stage reconstruction. For patients with skin and bone defects of the hand, a radial forearm osteocutaneous flap is recommended. This flap is also recommended for patients with traumatic thumb loss, if the dorsalis pedis artery is absent, or if the patient declines using tissue from the foot.

Adult↗
PubMed1999

Transfer of a pedicled venous flap containing perivenous areolar tissue and nerve: an experimental study.

In this paper, we evaluated experimentally the feasibility of transferring a pedicled venous flap with perivenous areolar tissue into an ectopic site and investigated the role of each vein, the perivenous areolar tissue and nerve in the viability of pedicled venous flaps. Three groups of flaps were created using a rabbit-ear model: Group 1 (n = 11), containing perivenous areolar tissue and a draining vein; Group 2 (n = 10), perivenous areolar tissue, a draining vein and nerve; Group 3 (n = 10), only perivenous areolar tissue. Macroscopic, angiographic and histological assessments were performed 14 days after transfer. The total survival areas including superficial necrosis of Groups 1, 2 and 3 were 52.7%, 82.5% and 0%, respectively. There were significant differences in mean survival area and mean total survival area including superficial necrosis between Group 1 and Group 2 (P < 0.05). In contrast, all flaps in Group 3 became necrotic. These data suggest that a preserved vein is the necessary condition, and additional arterial flow through the preserved nerve and a small vascular network within the areolar tissue may play an important role in flap survival.

Animals↗
PubMed1999

Choline acetyltransferase activity in collateral sprouting of peripheral nerve after surgical intervention: experimental study in rats.

The purpose of this study was to establish an assay of choline acetyltransferase (ChAT) activity to investigate the regeneration of injured peripheral nerve, repaired by end-to-end or end-to-side neurorrhaphy. Murine sciatic and peroneal nerves were exposed, and the peroneal nerve was transected at a site 5 mm from its ramification. For end-to-side neurorrhaphy, an epineurotomy producing a 5-x5-mm window was carried out on the tibial nerve, just above the level of gastrocnemius muscle ramification. The peroneal nerve stump was then sutured end-to-side to the tibial nerve window. For end-to-end neurorrhaphy, the peroneal stump was directly sutured end-to-end. ChAT activity was measured at a site distal to the peroneal stump at 1 to 3 months postoperatively, and the results were compared among four groups: 1) end-to-end neurorrhaphy group; 2) end-to-side neurorrhaphy group; 3) unrepaired group; and 4) positive controls. ChAT activity in the end-to-side neurorrhaphy yielded approximately two-thirds the value of the end-to-end neurorrhaphy, and more than half the value of positive controls at 3 months postoperatively. Histologic sections of the end-to-side and end-to-end sutured peroneal nerve demonstrated large numbers of myelinated axons and Schwann cells at the third postoperative month. All the results demonstrated that end-to-side neurorrhaphy is comparable to well-performed end-to-end neurorrhaphy, thus providing another option for surgical treatment of avulsion nerve injury and massive nerve defect.

Anastomosis, Surgical↗
PubMed1999

Free vascularized fibula grafts in surgery of the upper limb.

Twenty patients with intractable diseases in the upper extremity were treated using free vascularized fibula grafts. There were 13 men and seven women. Three patients had traumatic bone defects, five had post-traumatic nonunions, two had congenital pseudoarthroses, seven had defects after tumor resection, and three had other lesions. The reconstructed sites were the humerus in two patients, the radius and/or ulna in 17, and the metacarpal and phalangeal bones in one. The length of the bone defect ranged from 3 to 18 cm (mean: 8.4 cm). Follow-up periods ranged from 6 to 204 months. No patient required additional bone grafts. The mean period required to obtain radiographic bone union was 4.4 months. There were no cases with fractures of the grafted bone, but malunion occurred in four cases. The vascularized fibula graft is indicated in patients with large bone defects or intractable nonunions in the humerus, radius, and/or ulna.

Adolescent↗