PubMed Health⌕ Search

Biomedical subjects

I Nagai

Publications and source records attributed to I Nagai.

At least 19 recordsLinked to original sources
PubMed1992

Lung traction causes an increase in plasma prostacyclin concentration and decrease in mean arterial blood pressure.

The effects of lung traction on arterial blood pressure and plasma prostacyclin concentrations were studied in five patients undergoing partial pneumonectomy or lobectomy. After manual traction of a lung segment, mean arterial blood pressure decreased from 77 +/- 5 mm Hg (mean +/- SEM, before lung traction) to 59 +/- 5 mm Hg. The concentrations of 6-keto prostaglandin F1 alpha (a stable breakdown product of prostacyclin) increased significantly from 46 +/- 6 pg/mL (mean +/- SEM, before thoracotomy) to 593 +/- 91 pg/mL. Four of five patients showed facial flushing and palmar erythema. Arterial blood pressure returned to pretraction value, and both the facial flushing and palmar erythema disappeared within 30 min after lung traction. These results suggest that traction of the lung stimulates release and/or production of prostacyclin, which results in facial flushing, palmar erythema, and decrease in arterial blood pressure.

Adolescent↗
PubMed1992

[Clinical and histological effects of preoperative chemotherapy for squamous cell carcinoma of the tongue].

According to the effect of preoperative chemotherapy for tongue cancer, if the operation method is modified, the modality of treatment for tongue cancer will contribute to preserve the tongue in terms of function and aesthetics as well as improve the quality of life. A clinicopathologic study on 81 patients with tongue cancer was conducted to elucidate the relationship between clinical and histological effects of preoperative chemotherapy with a single agent and multiple-drug regimens, in order to determine the safe surgical margins in the resection of squamous cell carcinoma of the tongue. Fifty patients were treated with bleomycin alone, sixteen with bleomycin and methotrexate and another fifteen with bleomycin, OK-432 and cisplatin. Multiple-drug regimens resulted in greater response rates than the single agent, but there was not always agreement in the relationship between the tumor regression rate and the histological effects of chemotherapy. The histological effects, including the residual aspects of the tumor cell population, were associated with the grade of histological malignancy according to the mode of tumor cell invasion, mitotic index of tumor cell, the tumor differentiation, the degree of stromal lymphocyte infiltration and cellular atypism. These data indicate that special consideration should be also given to the degree of histological malignancy for biopsied specimen, in addition to the tumor regression rate, in determining safe surgical margins and in the modality of treatment of tongue cancer.

Adult↗
PubMed1991

[A case of tracheal benign mixed tumor].

A 44-year-old male was admitted because of dyspnea. Bronchoscopy revealed a tumor obstructing 85% of the tracheal lumen, at the site of the membranous portion, 3 cm below the vocal cords. The tumor was removed by sleeve tracheal resection with end to end anastomosis. Histological findings showed benign mixed tumor (pleomorphic adenoma) arising from the tracheal wall. Postoperative course was uneventful. Only 5 tracheal mixed tumors have been found in the Japanese literatures. Therapeutic approach to this tracheal tumor is discussed in this paper.

Adult↗
PubMed1991

[A case of neurofibromatosis 2 combined with a vagal neurilemmoma in the mediastinum].

A 39-year-old man was referred to our hospital for further evaluation of an abnormal mediastinal shadow on chest X-ray film. CT scan of the chest showed a cyst-like tumor in the mediastinum. CT scan of the brain to investigate the impairment of hearing revealed bilateral cerebropontine angle tumors. Histological examination of both tumors revealed neurilemmoma. Neurofibromatosis 2 combined with a vagal neurilemmoma in the mediastinum is very rare.

Adult↗
PubMed1991

[A case of squamous cell carcinoma of the thymus and thymic cyst].

A 57-year-old man was referred to our hospital for further evaluation of an abnormal mediastinal shadow detected on chest X-ray film. Chest CT showed a solid mass and a cyst. Operation revealed a squamous cell carcinoma of the thymus adjacent to a thymic cyst. Histologic examination demonstrated the clear separation of the squamous cell carcinoma and the thymic cyst by interstitial tissue. Cases of squamous cell carcinoma of the thymus combined with thymic cyst are very rare.

Carcinoma, Squamous Cell↗
PubMed1991

[A case of intrathyroidal thymoma presenting as a thyroid mass].

Intrathyroidal thymoma is a rare tumor that occurs in the thyroid gland. The present report describes a 62-year-old female patient with this tumor, who was treated with subtotal thyroidectomy with a wedge resection of the trachea followed by radiotherapy. She is now free from disease for 4 years after the operation. This tumor shows expansive growth, frequent invasion to the surrounding tissue, but relatively infrequent lymph node involvement. If this tumor is resected surgically, the prognosis is favorable.

Choristoma↗
PubMed1990

A case of middle lobe syndrome occurring in two sisters.

We report herein a rare case of middle lobe syndrome, occurring in two sisters. Since selective aspirations of sputum under bronchoscopic guidance proved ineffective, a middle lobectomy was performed in both cases. Histological findings of the resected specimens showed overgrowth of the bronchial glands, lymphocytic infiltration around the alveoli and glandular metaplasia of the alveoli in both cases. Based on the allergic diathesis, we suggest that in these 2 sisters, middle lobe syndrome was caused by chronic inflammation.

Child↗
PubMed1990

Absence of role for plasmids in resistance to multiple disinfectants in three strains of bacteria.

Three chlorhexidine-resistant strains, two of Achromobacter xylosoxidans, one of Pseudomonas cepacia, were isolated from clinical sources. The three strains showed cross-resistance to benzethonium chloride, benzalkonium chloride and alkyldiaminoethylglycine. Resistance persisted after treatment of the strains with acridine orange (12.5 mg-25 mg l-1). Conjugation to appropriate recipients of Escherichia coli was unsuccessful and plasmid DNA could not be detected. These results suggest that plasmids do not play a role in resistance to multiple disinfectants in the strains of bacteria studied.

Alcaligenes↗
PubMed1990

[A case of pulmonary metastasis from adenoid cystic carcinoma of the trachea].

A 33-year-old woman with adenoid cystic carcinoma of the trachea was treated by resection of the upper and mid-trachea, plus total laryngectomy, subtotal thyroidectomy, partial resection of the cervical esophageal muscle layer and mediastinal tracheostomy. This tumor invaded directly into the thyroid gland, the larynx, the recurrent laryngeal nerve and the cervical esophagus. Three years after the operation, metastases developed in the right lung (S10, S2) and partial resection of the lung was performed. This patient is now free from disease. Aggressive surgical resection is important for the improvement of survival in this condition, although this tumor shows low grade malignancy and is slowly growing.

Adult↗
PubMed1990

[Surgical treatment of upper mediastinum involvement following thyroid cancer surgery].

Four cases with mediastinal nodal involvements after surgery for thyroid cancer were treated by tumor extirpation and mediastinal lymph nodes dissection. The removal were performed via the median sternotomy in three cases and partial resection of the clavicle in one case. The transsternal approach made it possible to remove the tumor with mediastinal lymph nodes safely and easily. It is generally sufficient to carry out dissection as far as the brachiocephalic vein. However, mediastinal nodal involvements extending below the brachiocephalic vein were seen in one of 4 cases. All patients are alive, including 2 cases with lung metastases. Initial aggressive surgical treatment of mediastinal recurrence is important for preventing the obstruction of the trachea or large vessels.

Adult↗
PubMed1989

[Clinical analysis of 26 cases of multiple primary cancer].

Of 412 head and neck cancers in the Department of oral Surgery, Sapporo Medical College from 1976 to 1987, 26 cases (6.3%) were multiple primary cancers. One of these cases was triple cancer. The ages of these 26 cases ranged from 42 to 81 (average 61 year-old) with 20 males and 6 females (3.3:1). As to the interval between the first and second cancer, five cases (20%) were synchronous and twenty cases (80%) were metachronous in our series. Of the five synchronous, three were found by careful examination at the time of admission to our department. The stomach and head and neck cancers were frequently observed as the first cancer of metachronous cases. Second primary cancers occurred in the head and neck region were 64% and those in other regions were 36%. On the other hand, digestive cancer was predominant in the additional cancer to the index cancer (66.7%). These numbers emphasize that patients with head and neck cancers are in a cancer-prone group that develops digestive cancers. These findings have important implications in follow up policy.

Adenocarcinoma↗
PubMed1989

[Immunohistochemical localization of laminin and its relation to the grade of histological malignancy in oral cancer].

The immunohistochemical localization of Laminin has been investigated with a monoclonal antibody in biopsy specimens from 27 patients with an invasive squamous cell carcinoma of the oral cavity. In normal mucosa, laminin was found distributed in a linear pattern in the epithelial-stromal junction, around the blood vessels, the nerve fibres, and the skeletal muscle bundles. In the cancerous tissues a variety in the linear staining around the cancer cell nests was seen. Extreme attenuation or complete loss of the linear staining of laminin was demonstrated in 8/27 specimens, and these tumors histologically showed a high grade of malignancy with H.E. staining.

Basement Membrane↗
PubMed1986

Studies on the bacterial permeability of non-woven fabrics and cotton fabrics.

The permeability of cotton and non-woven fabrics to bacteria, air and water was studied. Non-woven fabrics, even when wet, showed low resistance to air, and high resistance to permeation of water and bacteria. Water-repellent cotton fabrics were resistant to permeation of water, air and bacteria, but these properties decreased on washing. Non-water-repellent cotton fabrics were poor bacterial barriers even when new.

Bacteria↗
PubMed1979

Effect of transverse tubule-disruption on 14C-caffeine influx in frog skeletal muscle.

Effect of transverse tubule-disruption (T-disruption) on 14C-caffeine influx was studied using small bundles, consisting of 40 to 50 fibers, of frog semitendinosus muscle. The peak tension of caffeine contracture was inhibited by about 69% at 5 mM caffeine and by about 31% at 7 mM caffeine by T-disruption. In addition, the amount of caffeine influx in a small bundle was inhibited by about 52% at 5 mM caffeine and by about 28% at 7 mM caffeine by T-disruption, corresponding to the inhibition of the peak tension of caffeine contracture by T-disruption. These findings support our previous suggestion that caffeine enters the muscle fibers through the surface membrane and transverse tubuler membrane (T-membrane), and that the T-membrane contributes to the entry of caffeine more greatly at 5 mM caffeine than at 7 mM caffeine. Moreover, at 5 mM caffeine it was noted that there is a slight difference between the extent of inhibition of the caffeine influx and that of the peak contracture tension. From these results, it could be concluded that the inhibition of peak tension of caffeine contracture by T-disruption is mainly due to the inhibition of caffeine influx which occurs through the T-membrane and is partly due to the functional disturbance of the sarcoplasmic reticulum which is probably induced by T-disruption.

Animals↗
PubMed1979

Effect of SCN on potassium contracture in twitch muscle fibers of the frog.

The effect of SCN on potassium contracture, especially the time course and the mechanical inactivation of the contracture, was investigated using frog twitch muscle fibers. SCN increased the magnitude and the rate of rise of the potassium contracture tension and prolonged its time course. These effects of SCN depended on the concentration of K+ in the external medium and on the duration of pretreatment of the fibers with SCN-Ringer solution. The potentiating effect of SCN on the potassium contracture tension was pronounced at lower and moderate concentrations of K+ and this effect attained a maximum within 1 min after the pretreatment. In the contracture induced by exposure of the fibers to K-SCN-solution without the pretreatment, the time course of the contracture, especially the retardation of the spontaneous relaxation, was marked at higher concentrations of K+. This retarding effect of SCN attained a maximum at more than 10 min after the pretreatment with SCN-Ringer solution. SCN shifted the mechanical inactivation curve of potassium contracture toward lower concentrations of K+, as in the case of the activation curve, and markedly increased the rate of the inactivation induced by conditioning with 15 mM K+. In addition, SCN delayed the recovery of potassium contracture from the mechanical inactivation induced by preceding K-SCN-contracture. On the basis of these results, the sites and the mechanism of action of SCN on potassium contracture are discussed.

Animals↗
PubMed1978

Caffeine contracture in transverse tubules-disrupted fiber and effect of anomalous anions on the contracture in frog twitch fiber.

Caffeine contracture in transverse tubules-disrupted (T-disrupted) muscle preparation and the effect of anomalous anions (SCN and NO3) on the contracture in single twitch fibers or thin bundles consisting of 2 or 3 fibers of frog were investigated. The magnitude and the rate of rise of caffeine contracture tension were decreased by T-disruption and the decrease was more marked at lower concentrations of caffeine. No seasonal difference between summer and winter frogs on the effect of T-disruption on caffeine contracture was observed. On the other hand, the magnitude and the rate of rise of caffeine contracture tension in the intact preparation was increased by anomalous anions, whereas the rate of spontaneous relaxation of the contracture was decreased. The effect of SCN on caffeine contracture appeared 5 min after the pre-exposure of muscle preparation of SCN-Ringer solution, with the maximal effect appearing after 10 min. The threshold curve of caffeine contracture was shifted toward the lower caffeine concentrations by anomalous anions and the extent of the shift in the curve was more pronounced with SCN than with NO2. In contrast, the potentiating effect of these anions on the caffeine contracture completely disappeared in T-disrupted muscle preparation. On the basis of these results, the caffeine pathway to the sarcoplasmic reticulum, and the sites and mechanism of the action of anomalous anions on caffeine contracture are discussed.

Animals↗