Biomedical subjects
Publications and source records attributed to S Tamai.
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Increase in intestinal blood flow was observed in a patient with postprandial hypotension. Simultaneous measurement of hemodynamic parameters and plasma levels of gut hormones revealed that the release of various vasoactive substances and resulting vasodilation of abdominal organs were responsible for the vasomotor changes of early dumping syndrome.
In vitro and in vivo experiments were carried out to study mechanical effects of the cushioned plate fixation in which a cushion was placed between a metal plate and bone. The cushioned plate fixation was found to be flexible in the physiological stress range and to reduce the stick slip between bone and the plate. A blood-soaked compression test indicated that the cushion moderates the stress shielding effect which occurs in the vicinity of the rigid plate, this being consistent with the result of in vivo experiments.
The clinical significance of symptomatic talocalcaneal coalition was described subjectively, objectively, and identified roentgenographically after examining 67 feet of 42 patients between 1977 and 1987. Computed tomographic examinations, conducted on 29 of 42 patients, were useful in recognizing the extent of coalition, the condition of union, and the postoperative results. Tarsal tunnel syndrome was present in 23 feet with the coalition. Thirty-one feet (24 patients) were treated conservatively and 36 feet (29 patients) surgically. Of the surgically treated feet, the coalition was excised in 33 and talocalcaneal fusion was performed in three. Follow-up examinations were performed at an average of 5.3 years (range, 2.25-11.2 years). In the excision group, the results were excellent in 24 feet, good in seven, and fair in two. The results were good in three feet treated by arthrodesis.
The L-myc DNA-restriction fragment length polymorphism, revealed by EcoRI, has been studied in both a lung cancer case-control framework and a cohort of 40 non-diseased unrelated individuals. No association was found between the L-myc allelic frequencies and disease status, tumor stage or lung cancer histology. A strong association was, however, observed between the L-myc allelic frequencies and ethnic origin (black or white) of the subjects. Among American whites the allelic distribution at the L-myc proto-oncogene locus was almost identical to that previously reported for Japanese subjects. Among the American black population there was a significantly higher frequency of the presence of the polymorphic EcoRI restriction site in the second intron of the L-myc proto-oncogene. These data emphasize the importance of conducting epidemiologic studies that control for ethnic factors and indicate that L-myc EcoRI allelotypes do not appear to be predictive of lung cancer risk or disease status in American blacks and whites.
We examined the adrenocorticotropic hormone-releasing activities of several human interleukin-1 beta analogues that have markedly reduced pyrogenic activities in rats. Among the analogues tested, [Gly4]-, [Leu93]- and [1-148]-interleukin-1 beta increased the plasma adrenocorticotropic hormone level to almost that induced by authentic human interleukin-1 beta. Modifications of the N-terminus of the authentic molecule, i.e., [7-153]- and [Des-Ala1, Asp4]-interleukin-1 beta, significantly reduced the hormone-releasing activity. These data suggest that the adrenocorticotropic hormone-releasing activity of human interleukin-1 beta resides in the N-terminal structure of the authentic peptide and can be separated from its pyrogenic activity.
To investigate the bone formation ability of porous hydroxyapatite (HA) and tricalcium phosphate (TCP), ceramic discs were implanted with or without rat marrow cells into subcutaneous sites in syngeneic rats. The discs of HA and TCP had identical microstructures: pore size was 190-230 microns, porosity was 50-60%, and they were fully interconnected. Implants without marrow cells (discs themselves) did not show bone formation, whereas implants with marrow cells showed bone formation in the pores of the ceramics. The bone formation of both HA and TCP occurred initially on the surface of the ceramic and progressed towards the center of the pore. The de novo bone was quantitated from decalcified serial sections of the implants. One month after implantation with marrow cells, the percentage fractions of the pore area filled with bone for implanted HA and TCP were 16.9 and 15.1, respectively. At 2 months after implantation with marrow cells, the fractions of bone were 34.3 and 30.9, respectively. These results indicate that both HA and TCP ceramics can show comparable osteogenic ability in the presence of marrow cells.
Synovial osteochondromatosis of the hand is uncommon, except for tenosynovial chondromatosis of the digits. It is even more rare in the wrist joint. A patient with synovial osteochondromatosis of the distal radioulnar joint that involved the triangular fibrocartilage complex is described. At operation, synovectomy, excision of osteochondral bodies, and removal of the entire triangular fibrocartilage complex was done. The triangular fibrocartilage complex was reconstructed using part of the extensor carpi ulnaris tendon. One year after operation, the patient had regained almost full range of motion and is without pain.
From May 1958 to May 1987, 331 digits were replanted successfully with an overall survival rate of 86.2%. Complete success in replantation of amputated fingers requires an accurate anastomoses of both arteries and veins. However, anastomosis between arteries may not be possible in some patients. Since reports that a thumb amputated at the interphalangeal joint area could be successfully replanted by an arteriovenous shunt on the palmar side, we did arteriovenous shunts in four such cases. Two replantations were successful; necrosis developed in the other two patients.
In previous studies using rabbit ears, total venous perfusion flaps (TVPF) were used that did not contain in the experimental model any chosen arteries truly representative of clinical venous flaps. We discovered that the TVPF could survive even under conditions of poor blood circulation. In the present study, conditions of the recipient veins were investigated using flow-through veins in TVPFs of rabbit ears and human dorsal digital veins. The research suggested that conditions for TVPF survival are a high density of the venous network in the flap and the presence of venous oscillation, high oxygen tension, and effective blood flow in the recipient vein.
In free tissue transfer, the recipient arteries and veins are often damaged by injury, and their lumens are often narrowed due to thickening of the intima. These factors are considered paramount in the poor success rate of free tissue transfers. In the reported study, the authors examined the effects of continuous intraarterial infusion with heparin and urokinase in experimental epigastric flap transfer. By intraarterial infusion, the drug concentration at the target site could be significantly increased. The viability of an epigastric flap transferred to a recipient site with thickened arterial intima was significantly improved in a rabbit model by a seven-day continuous local intraarterial infusion of heparin at 10 U/kg/hr and urokinase at 100 IU/kg/hr, compared with control or intravenous infusion. Use of an anticoagulant with a fibrinolytic enzyme is considered to be the best choice for a successful outcome in flap transfer.
To assess the chronic effects of interleukin-1 (IL-1) and IL-2 on the hypothalamo-pituitary-adrenal axis in vivo, we administered recombinant human (rh) IL-1 alpha, rhIL-1 beta or rhIL-2 (2.0 micrograms/day) repetitively to adult male rats for 10 days. In rhIL-1 beta-treated rats, adrenocorticotropic hormone-like immunoreactivity (ACTH-LI) of the anterior pituitary appeared to increase first on day 3 followed by an increase of corticotropin-releasing hormone (CRH)-LI both in the hypothalamus and in the adrenal gland after day 7. At the end of the 10-day treatment, wet weights of the adrenal glands of rhIL-1 beta-treated rats increased significantly compared with those of control rats. Plasma ACTH levels in rhIL-1 beta-treated rats at the sampling time continued to be elevated throughout the experimental period. Under the same experimental design, rhIL-1 alpha increased plasma ACTH levels at the sampling time without changes in adrenal weight or in the peptide contents investigated. The same amount of rhIL-2 had no effect on these measured variables during the 10-day treatment. These data indicate that the repetitive administration of IL-1 beta resulted in chronic effects in the hypothalamo pituitary-adrenal axis to increase the activities in these organs during the treatment and, moreover, IL-1 possibly has a positive direct effect on the CRH-containing cells in the adrenal glands.
Methylprednisolone (MP) is frequently used in shock states, its antishock mechanisms, however, have not been clarified. Effect of MP 10 mg.kg-1 on granulocyte beta-adrenoceptor density was studied in two patients who required dopamine infusion postoperatively. The granulocyte beta-adrenoceptor density was calculated from the binding of [3H] dihydroalprenolol. Arterial blood pressure and cardiac output increased 1 hr after MP administrations. Beta-adrenoceptor densities were low in both cases prior to the administration of MP (16.1 and 24.6 fmol.mg-1 protein), which increased 11 hr after MP (31.2 and 35.8 fmol.mg-1 protein, respectively). The effects of MP to improve status of cardiovascular system in patients receiving catecholamine-infusion may be associated with the increase in the density of myocardial "down-regulated" beta-adrenoceptor.
Miliary tuberculosis associated with cutaneous lesion has been rarely reported. We report a case of miliary tuberculosis in whom the cutaneous lesion was confirmed as tuberculosis by skin biopsy and bacterial examination. A 46-year-old man was admitted because of cough, fever, sore throat and abnormal shadow on the chest X-ray. Physical examination revealed an emaciated man with two ulcerous lesions overlying yellowed crust on the chest wall and fine crackles on the left side of the lung. Laboratory workup revealed a white blood cell count of 10,000 with 15% lymphocytes and positive CRP. Chest X-ray film showed the infiltration with cavity formation in left upper lung field and nodular dissemination. His tuberculin reaction was negative on admission. Sputum, urine and secrete from cutaneous lesion were positive for the acid-fast bacilli and the culture grew Mycobacterium tuberculosis. Examination of the skin biopsy specimen and bone marrow aspiration showed Langhans giant cells around necrotic lesion; therefore the diagnosis of miliary tuberculosis was made. After an initiation of antituberculosis therapy with combined regimen composed of streptomycin (SM), isoniazid (INH), ethambutol (EB) and rifampicin (RFP), this patient improved significantly. Although the case report of miliary tuberculosis tends to increase recently, the report of cutaneous lesion is relatively rare in association with miliary tuberculosis. We discussed this subject with reference to the literatures.
Choriocarcinoma is a potentially curable neoplasm. Although the presence of brain metastases worsens the ultimate prognosis, aggressive therapeutic intervention is sometimes justified for brain metastases of a potentially curable neoplasm. In the present clinical report, we present two cases of choriocarcinoma with brain metastasis manifesting neurological deterioration, and discuss treatment strategies. From the results of treatment, we conclude that surgical removal of the lesion, followed by chemotherapy combined with irradiation, should be the treatment of choice in patients with progressive neurological deterioration.
Japan Society of Clinical Pathology has formed a committee dealing with "lab. tests in primary care medicine". As the first step, they made "Essential Lab. Tests" which were composed of simple qualitative bed-side tests such as urinalysis, Complete blood count (CBC: Hb, Ht, WBC, RBC), CRP, or ESR (Erythrocyte sedimental rate), A/G ratio and biochemical tests if necessary (Table 1). We have performed "Essential Lab. Tests" on 1,026 outpatients who visited General Medicine Clinic for the first time. They consisted of 456 male (age 13-81), and 526 female (age 10-85). This report is the result of urinalysis from "Essential Lab. Tests" of 1,026 patients. 1) The result showed that overall positivity of the urinalysis was 21.3% (when more than one item of the qualitative tests was positive). 2) There was distinctive difference in the positivity of the urinalysis between the sex; i.e. protein and glucose were about twice frequently positive in male, where as occult blood and WBC (Esterase reaction) were 2-3 times more positive in female. 3) Urine protein shows positive in the individual 10-20 yrs old and more than 50 yrs old in both sexes. 4) Glucose was positive in over 40 yrs in male, and occult blood, 40-50 yrs or older in male. 5) WBC shows positive in all age groups in female and 50 yrs or older in male. 6) Positive WBC patients did not necessarily reflect urinary infection in female but nitrites roughly corresponded with urinary WBC in male of 50 yrs or older, meaning probable urinary infection associated with prostatic hypertrophy. 7) Abnormality of urinary sediment corresponded to the positive occult blood and WBC Erastase. 8) Urinalysis is an useful method of screening in primary care medicine.
From 1975 to 1980, total ankle arthroplasty was performed using a metal and polyethylene prosthesis on 30 ankles in 28 patients with painful arthritis. However, because loosening and sinking of the prosthesis were significant, a ceramic total prosthesis was designed in 1980 to be used without cement. Between 1980 and 1987, 39 ankles in 35 patients with osteoarthritis, rheumatoid arthritis, and hemophilic arthritis were replaced using the ceramic prosthesis. Out of 39 ankles, nine were replaced with cement and 30 without cement. The follow-up period for the cemented metal and ceramic cases ranged from 13.4 to 6.2 years, with an average of 8.1 years, and for uncemented ceramic cases from 1.2 to 6.4 years, with an average of 4.1 years. Based on a rating scale for ankle evaluation, 27% of the cemented cases and 67% of the uncemented cases are satisfactory. Five metal ankles and one ceramic ankle were reoperated upon, with one revision and five arthrodeses performed. Ceramic total ankle arthroplasty, performed without cement, has to date provided mostly excellent stable results.
We compared adrenocorticotropin-releasing activities of several interleukins in a homologous or heterologous in vivo system. Intravenous injection of rat interleukin-1 alpha significantly increased plasma adrenocorticotropin in conscious, freely-moving rats 30 min after the injection, and the effect was 10 times greater than that of human interleukin-1 alpha. Rat interleukin-2 affected plasma adrenocorticotropin in a much slower manner and increased its levels significantly 120 min after the injection. Human interleukin-2 had no effect on plasma adrenocorticotropin. Thus, species difference in the experimental system should be considered to assess the physiological significance of cytokines in the neuroendocrine system.