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Biomedical subjects

T Takata

Publications and source records attributed to T Takata.

At least 127 records · Page 7Linked to original sources
PubMed1995

[A case of myotonic dystrophy with impairment of smooth pursuit eye movement].

We reported a 36-year-old woman of myotonic dystrophy with impairment of smooth pursuit eye movement. The patient, whose mother was also affected, had psychomotor retardation from childhood. DNA analysis by Southern hybridization technique showed large DNA fragment (14/8.6 kb). Oculomotor limitation and gaze nystagmus were not observed, and saccadic eye movements were normal. In electrooculography, smooth pursuit eye movements were impaired toward both directions, and interrupted by saccades. The caloric test elicited a satisfactory response, but the visual suppression test produced no suppression. CT scan displayed paraventricular low density area, and MRI showed the multiple foci of high signal intensity in the white matter on T2-weighted images. No changes were detected on CT or MRI in the brainstem and cerebellum. The lesions in the brain are considered to be correlated with smooth pursuit impairment.

Adult↗
PubMed1994

Lactate threshold is not an onset of insufficient oxygen supply to the working muscle in patients with chronic heart failure.

It has been argued that the lactate threshold (LT) serves as an index to reflect circulatory insufficiency in transporting oxygen during submaximal exercise in patients with chronic heart failure (CHF). We examined whether or not the LT was related to an insufficient oxygen supply in patients with CHF. Sixty-nine patients were divided by NYHA classification. All underwent invasive cardiopulmonary exercise testing. The rate of increase in oxygen delivery (O2D) versus VO2 (delta O2D/delta VO2) was significantly lowered when work rate exceeded LT, that is, 1.32 +/- 0.35 to 1.05 +/- 0.37 (p < 0.01), 1.22 +/- 0.40 to 0.98 +/- 0.40 (p < 0.05), and 1.04 +/- 0.26 to 0.78 +/- 0.39 (p < 0.05) in NYHA classes I, II, and III, respectively. However, the rate of increase in leg O2D versus leg VO2 (delta LO2D/delta LVO2) did not change, that is, 1.25 +/- 0.20 to 1.29 +/- 0.20 (NS), 1.27 +/- 0.23 to 1.21 +/- 0.28 (NS), and 1.19 +/- 0.24 to 1.15 +/- 0.17 (NS) in classes I, II, and III, respectively. Leg venous PO2 was significantly different among three groups, that is, 23.7 +/- 3.4 mmHg, 23.2 +/- 2.8 mmHg, and 20.1 +/- 2.3 mmHg (p < 0.001), respectively. Thus, the oxygen supply to the working muscle did not become insufficient when work rate exceeded LT, and the LT occurred at different levels of leg PO2. It was concluded that the LT was not a result of anaerobiosis in patients with CHF.

Anaerobic Threshold↗
PubMed1994

Effect of polylactic acid on osteoinduction of demineralized bone: preliminary study of the usefulness of polylactic acid as a carrier of bone morphogenetic protein.

To evaluate the usefulness of polylactic acid (PLA), a bioabsorbable and plastic polymer, as a carrier of bone morphogenetic protein (BMP), a preliminary study has been carried out to investigate any negative effect of PLA on osteoinduction of demineralized bone (DB). PLA (10,600 mol. wt) was mixed with DB particles (1-1.5 mm square) prepared from rat femurs and laid subcutaneously on the intercostal muscle of 4-week-old Wistar rats. The PLA/DB pellets were harvested at 2, 4, 8 and 24 weeks after the operation, and prepared for light microscopic examination. Histological examination revealed cartilage formation at 2 weeks and new bone formation at 4 weeks. Extensive bone and marrow formation were observed at 24 weeks. PLA was gradually absorbed and completely disappeared at 24 weeks to be replaced by connective tissue. These results demonstrate that PLA does not have a negative influence on the osteoinductive activity and that PLA could well be a promising bioabsorbable carrier of BMP.

Animals↗
PubMed1994

Prognostic value of argyrophilic nucleolar organizer regions (AgNOR) count in adenoid cystic carcinoma of salivary glands.

A retrospective study was performed on 34 patients with adenoid cystic carcinoma (ACC) to see if quantification of argyrophilic nucleolar organizer regions (AgNOR) was correlated with their prognosis. Mean follow-up period was 113 months. According to detailed clinical data that included tumor recurrences, metastases and patient survival conditions, two groups were classified. Group 1 consisted of 20 live patients without metastases, of whom 16 were free of disease, while group 2 comprised 14 patients with metastases among whom 12 died of tumor. The silver staining technique was applied to paraffin embedded specimens. In each case, 300 nuclei were randomly examined and the mean AgNOR per nucleus was calculated. All patients from group 2 had mean AgNOR counts greater than 4, whereas 65% of patients from group 1 had mean AgNOR counts less than 4. In addition, statistical analysis showed that the pooled mean AgNOR count in group 2 was significantly higher than in group 1 (P < 0.01). The present results suggest that silver staining technique promises to be a useful supplementary method for prognostic evaluation of salivary ACC, and may be performed before planning the treatment.

Adult↗
PubMed1994

Thermal- and photo-polymerization of (meth) acrylates containing a spiro ortho ester moiety and the properties of poly[(meth)acrylate]s.

The syntheses and polymerizations of acrylate (ASOE) and methacrylate (MASOE) containing spiro ortho ester moieties were carried out and the properties of the polymers obtained were investigated. The ring-opening reaction of the spiro ortho ester groups proceeded well during heat polymerization (HC) with the ionic initiators (BSS and HPSS). However, a small amount of unreacted carbon-carbon double bond was observed in the polymers obtained. Not only vinyl polymerization but also a small amount of ring-opening reaction took place during polymerization with radical initiators (BPO, AIBN, DTB and CQ). The poly-(MASOE)s obtained by HC with BSS, BSS/AIBN and BSS/BPO were plastic like polymers. Low volume shrinkage was observed during HC and UVLC of ASOE and MASOE with ionic initiators. These shrinkages were smaller than those of conventional methacrylate.

Acrylates↗
PubMed1994

[Amebic empyema, a case report].

A 49-year-old man was admitted to our hospital for dyspnea. Chest X-ray examination showed a massive right pleural effusion. Using intrathoracic tube drainage, a large quantity of chocolate-like pleural effusion was removed. Laboratory data demonstrated severe anemia and hypoproteinemia, and TPHA was positive. Antiameba antibody in blood was high, and a liver abscess was demonstrated on abdominal CT scan. Amebic liver abscess and amebic empyema were thus diagnosed. With pleural tube drainage and percutaneous liver abscess drainage, metronidazole (1.5 g/day) was administered. After administering this drug, the high temperature normalized and the patient's general condition improved significantly. Recently, amebic infections have been reported in increased numbers, especially in male homosexuals and immunocompromised patients. Henceforth amebic infection should be considered when pleural effusion and empyema are suspected.

Empyema, Pleural↗
PubMed1994

Oral wound healing concepts in periodontology.

The goal of periodontal treatments is the complete restoration of the structure and function of damaged periodontal tissues. Although it is very difficult to attain this goal, recent advances in periodontal wound healing concepts encourage hope of reaching it. Through reconsideration of the general concepts of wound healing and a review of the key and current literature on periodontal tissue regeneration, it is currently promised that this goal will be accomplished possibly by 1) spontaneous inherent tissue regeneration elicited by the elimination of causal factors; 2) guided tissue regeneration by the selective guidance of periodontal ligament cell proliferation; and 3) inductive tissue regeneration through recent advances in cellular biology.

Guided Tissue Regeneration, Periodontal↗
PubMed1993

Verruciform xanthoma of the oral mucosa: a clinicopathological study with immunohistochemical findings relating to pathogenesis.

Verruciform xanthoma is an uncommon benign lesion with unknown aetiology and pathogenesis. In this study, we report ten cases of verruciform xanthoma and document their clinical and histopathological findings. An immunohistochemical investigation was performed using antibodies to macrophage, leukocyte common antigen, T lymphocytes, B lymphocytes, S-100 protein, lysozyme and alpha-1-antichymotrypsin. Our results were similar to the other reported cases. Eighty percent of our cases were found on the gingiva. Candidal hyphae were found in the superficial parakeratotic layers in five cases. The clinical diagnosis of the lesion ranged between papilloma and squamous cell carcinoma. It is important for clinicians to take into consideration the possibility of verruciform xanthoma in the differential diagnosis of papillary and granular lesions of oral mucosa. Immunohistochemically, all foam cells were strongly stained with antimacrophage antibodies. T lymphocytes were the predominant infiltrating lymphocytes in the lesion. Langerhans cells in the epithelia were fewer than those in corresponding normal tissue. Our immunohistochemical findings suggest that verruciform xanthoma is may be a local immunological disorder, with a cell mediated mechanism.

Adult↗
PubMed1993

New periodontal ligament formation on a synthetic hydroxyapatite surface.

The aim of this study was to investigate whether a new connective tissue attachment can occur on a surface of hydroxyapatite (HA) when periodontal ligament (PDL)-derived cells with the ability to form new connective tissue attachment are allowed to populate the surface of HA. Six maxillary canines from 3 cats were used for this experiment. Under anesthesia, fenestration of the buccal alveolar bone was performed over the canine root and a cavity was prepared on the root surface. A synthetic HA block was inlaid and cemented into the root cavity. A Teflon membrane was then placed to cover the access opening of the alveolar bone to guide PDL-derived cell proliferation into the surface of the HA block. Finally, the gingival tissue flap was replaced and sutured. Six months after the operation, histologic evaluation was done by serial sections. In 4 of the 6 canines, PDL-derived cells successfully populated the HA surfaces and a layer of cementum-like tissue was formed on the HA blocks. A PDL-like connective tissue layer was seen between the cementum-like layer covering the exposed HA surface and the newly formed alveolar bone sealing the bone fenestration. Collagen fibers in the PDL-like tissue inserted their ends into the newly formed bone and the cementum-like tissue. The present findings demonstrated that PDL-derived cells can form a new connective tissue attachment on HA.

Animals↗
PubMed1993

Jaw cysts with orthokeratinization: analysis of 12 cases.

The clinico-pathologic, immunohistochemical and radiological features of 12 jaw cysts with a prominent orthokeratinized epithelial lining were studied and compared with those of typical odontogenic keratocysts and dentigerous cysts. They differed significantly from odontogenic keratocysts in terms of biologic behavior and histopathologic findings. Although immunohistochemical staining of the epithelial linings for cytokeratins, EMA, CEA and involucrin has not shed any light on the histogenesis of these lesions, staining patterns for these markers were significantly different from those of odontogenic keratocysts and non-keratinized dentigerous cysts. Radiologically, nine cases appeared as dentigerous cysts; two cases, one with sebaceous differentiation, as non-dentigerous unilocular cysts, and the remaining one was exceptional as it showed multiple epidermal cysts with prominent dermal appendages histologically. It is suggested that most of the orthokeratinized jaw cysts may belong to clinico-pathological entities different from odontogenic keratocysts with the majority representing dentigerous cysts with orthokeratinization. The possibility of the existence of rare central dermoid or epidermoid cysts is also to be considered.

Adolescent↗
PubMed1993

Proliferative activity of salivary gland pleomorphic adenomas and myoepitheliomas as evaluated by the proliferating cell nuclear antigen (PCNA) labeling index (LI).

Thirteen examples of pleomorphic adenoma (PA) and 4 of myoepithelioma (Me, 2 plasmacytoid cell type, 2 mixed cell type) were examined with respect to their proliferative activity on the basis of proliferating cell nuclear antigen (PCNA) immunohistochemistry. In PA, PCNA labeling index (LI) in tubular/trabecular/solid areas was significantly higher than that in myxomatous or chondroid areas. Although the mean value of LI in PA and Me was not statistically different (PA; 3.02 +/- 1.03%, Me; 3.19 +/- 1.76%), the Me of mixed cell type composed of epithelial, spindle or clear neoplastic myoepithelial cells had significantly higher LI, indicating the possibility of more rapid growth than PA. The small difference in the mean value of PCNA LI between PA and the mixed cell type of Me, however, suggests that enucleation with a margin of normal uninvolved tissue remains the recommended treatment for Me, as well as for PA.

Adenoma, Pleomorphic↗
PubMed1993

Non-calcifying Pindborg tumor with Langerhans cells.

A rare case of calcifying epithelial odontogenic tumor (CEOT) devoid of calcification is reported with histochemical, immunohistochemical and electron microscopic studies. The tumor occurred intraosseously in the left maxillary canine and premolar region of a 58-year-old man. The tumor chiefly consisted of scattered small islands of epithelial cells in an abundant fibro-myxoid connective tissue stroma. Among the nests, there were many spherical bodies of eosinophilic substance for which non-AA amyloid and non-keratin or basal lamina-like natures were demonstrated histochemically and immunohistochemically. In some nests, there were a few, occasionally several, cells positive for S-100 protein. Ultrastructurally, Langerhans cells with indented nuclei and Birbeck's granules were seen among tumor cells. The prognostic significance of the paucity of calcification and the presence of Langerhans cells in CEOT of which this is only the second description is discussed.

Calcinosis↗
PubMed1993

Magnetometric evaluation of the effects of gallium arsenide on the clearance and relaxation of iron particles.

Intratracheal instillation of GaAs suspension has been histopathologically shown to induce a diffuse pulmonary response. In the present study, magnetometry was used to evaluate the effects of intratracheally instilled GaAs on the behavior of externally magnetized iron particles instilled in rabbit lung. Magnetometric evaluation of the effects of GaAs in rabbits dosed with 30 mg or 300 mg/animal showed significant decreased relaxation of iron particles at 1, 3, 7, 14, 21 and 28 days following instillation compared with the controls. Relaxation indicates a rapid decrease of remanent magnetic field following magnetization of the lungs due to random rotation of phagocytized iron particles in macrophages. Clearance of the iron particles was measured by serial determinations of the remanent magnetic field at the end of magnetization estimated from relaxation curves. Clearance was significantly impaired in rabbits exposed to both doses of GaAs at 14, 21 and 28 days after instillation. Dose-effect relationships were observed in both cases. Histological examination of lungs instilled with these doses indicated active phagocytosis of GaAs and iron particles by alveolar macrophages.

Animals↗
PubMed1993

[TV-assisted thoracoscopic surgery with a lung forceps combined with thoracoscope under local anesthesia for spontaneous pneumothorax with a persistent air leak--a single access port approach].

TV-assisted thoracoscopic surgery was performed under local anesthesia by through a single access port to control a continuing air leak in spontaneous pneumotorax. A 75-year-old man was admitted with severe dyspnea and right-sided chest pain. The chest X-ray film showed right lung collapse. A right spontaneous pneumothorax was diagnosed and was treated by chest tube drainage. However, the lung did not re-expand because of a continuing air leak and subcutaneous emphysema developed. TV-assisted thoracoscopic surgery was performed under local anesthesia to treat the persistent air leak on day 12. By endoscopy, the ruptured bulla was double-ligated with an Endoloop through a single access port using lung forceps combined with endoscope. The air leak subsequently ceased and the lung re-expanded. This method is minimally invasive and is very suitable for controlling a continuing air-leak causing spontaneous pneumothorax in a patient.

Aged↗
PubMed1993

[Local resection of pulmonary lesions by Nd-YAG laser without suturing].

Local excision of 67 pulmonary lesions in 5 patients was performed with the Nd-YAG laser. There were 2 women and 3 men with an average age of 68 years. The patients consisted of three cases of metastatic lung cancer (65 lesions), one hamartoma (One lesion) and one organized pneumonitis (one lesion). The lesion was first enucleated by a contact method using an Nd-YAG laser scalpel, then the crater of the resected lesion in the normal lung tissue was coagulated with a defocused laser beam. The craters of 52 of the 67 resected lesions which were shallow seated in the lung were left open, but the other 15 resected lesions were closed with sutures. Total blood loss was less than 100 ml. There was no bleeding or air leakage (30 cm water pressure) during the post operative days in 4 of the 5 patients, but one patients (one lesion) had to be treated by bronchoscopic endobronchial embolization against a persistent air leak. This lesion was 2.5 cm in diameter and 4 cm deep in the lung on CT. The other lesions were also measured by CT. The tumor size was 1.4 +/- 0.7 cm and the depth was 2.4 +/- 1.0 cm. The Nd-YAG laser is very suitable for local resection of peripheral lung lesions without suturing.

Aged↗