Biomedical subjects

S Teramoto

Publications and source records attributed to S Teramoto.

At least 217 records · Page 12Linked to original sources

PubMed1994

Age-related changes in the antioxidant screen of the distal lung in mice.

We studied the influence of age on glutathione (GSH) content in the distal lung and the lung tissue of mice. From 1 to 28 months of age, the quantity of GSH and glutathione disulfide (GSSG) in bronchoalveolar lavage (BAL) fluid and in the lung tissue were determined. The GSH content in BAL fluid, which reflects the antioxidant screen of the distal lung, decreased with advancing age. The ratio of GSSG to GSH increased in later life, suggesting increase of oxidation of the epithelial lining fluid in old mice. The GSH content in the lung tissue also decreased with aging. Therefore the lower respiratory tract may be less able to defend against external attack, including attack by oxygen-derived active molecules, in senescent mice. The decrease of the antioxidant screen of the distal lung may be associated with impaired lung defense in relation to oxidant-antioxidant balance in aged mice.

Aging↗

PubMed1994

The effect of myocardial preservation technique on supraventricular tachycardia following aortic valve replacement.

We studied 100 patients who underwent an isolated aortic valve replacement (AVR) between 1974 and 1991. The patients were divided into the following two groups and compared: group A, which consisted of 40 patients operated on before 1978 who underwent continuous left coronary perfusion with blood; and group B, which consisted of 60 patients operated on after 1979 in whom St. Thomas solution was used in combination with topical cardiac cooling. Moreover, we divided the group B patients into two subgroups: group B1, who underwent AVR before 1986 during which we administered St. Thomas solution with ice slush every 30 min; and group B2, who had AVR after 1986 in which we used St. Thomas solution with a cold saline (4 degrees C) solution and treated with a small amount of slushed ice very 15 min. The incidence of supraventricular tachycardias was 15% in group A, 50% in group B1, and 15% in group B2. The severity of preoperative New York Heart Association (NYHA) functional class, the type of valve lesions, cardiothoracic ratio, left ventricular function, aortic clamp time, bypass time, and use of drugs did not correlate with the incidence of supraventricular tachycardias in either group A or B. In group B2 patients, we paid a lot of attention to cooling the right atrium as well as the left ventricle by immersing the whole heart using a 4 degrees C saline solution, which led to a remarkable reduction of the incidence of supraventricular tachycardia. This fact indicates that right atrial preservation is one of the most important factors for reducing the incidence of supraventricular tachycardia.

Aortic Valve↗

PubMed1994

[An evaluation of pathogens in patients with bronchopulmonary infection by transtracheal aspiration: December 1978-March 1993].

We performed transtracheal aspiration (TTA) in 1165 patients, who were suspected to have bronchopulmonary infection, from December 1978 to March 1993. We isolated pathogens from TTA in 806 patients (69.2%). We isolated H. influenzae (62 cases), S. pneumoniae (39 cases) and M. catarrhalis (24 cases) in patients with acute bronchitis, S. pneumoniae (65 cases), alpha-Streptococcus sp. (52 cases), H. influenzae (32 cases) and S. aureus (29 cases) in patients with pneumonia or lung abscess and H. influenzae (174 cases), S. pneumoniae (84 cases), P. aeruginosa (81 cases) and M. catarrhalis (42 cases) in patients with chronic lower respiratory tract infection. Anaerobic bacteria isolated from TTA included Peptostreptococcus sp. (19 cases), Bacteroides sp. (19 cases) and others. Mycoplasma pneumoniae was isolated from TTA in 8 patients with pneumonia without other organisms. Virus isolated from TTA included Rhinovirus (6 cases) and others. These results suggest that various pathogens affect the pathogenesis of bronchopulmonary infection. Therefore, we must diagnose the bronchopulmonary infection by the correct methods such as TTA.

Adult↗

PubMed1994

[A clinical study of respiratory infections due to mucoid Pseudomonas aeruginosa diagnosed by transtracheal aspiration].

We performed a clinical study of 20 cases (33 episodes) of respiratory infections due to mucoid Pseudomonas aeruginosa by transtracheal aspiration (TTA) in the recent 10 years. There was only one pneumonia without underlying chronic lower respiratory infection (CLRTI) case positive for mucoid P. aeruginosa and others were all CLRTI among 33 TTA trials. In contrast, nonmucoid P. aeruginosa was recovered from 9 cases of respiratory infections without underlying CLRTI among 46 TTA trials. Monomicrobial infection of mucoid P. aeruginosa was 69.7%, and polymicrobial infection containing mucoid P. aeruginosa was 30.3%, and Haemophilus influenzae was the most frequent microorganism recovered with mucoid P. aeruginosa. The recovery rate of mucoid P. aeruginosa among P. aeruginosa-colonized cases was 56.3% in diffuse panbronchiolitis, and that was 42.9% and 40.0% in bronchiectasis and chronic bronchitis, respectively. Mortality due to pneumonia with nonmucoid P. aeruginosa was 46.1%, but there was no fatal pneumonia case with mucoid P. aeruginosa. In CLRTI, laboratory data were not remarkably different between mucoid and non-mocoid P. aeruginosa-colonized cases. Thus, these results suggest that mucoid P. aeruginosa is a more important organism in persistent infections in the lower respiratory tract compared with nonmucoid P. aeruginosa, and further investigations is required on the mechanism and clinical role of this infection.

Adult↗

PubMed1994

[The role of viral infection in adults with bronchopulmonary infections].

We isolated the virus from the respiratory specimens of 16 patients (7.9%) when we investigated the bronchopulmonary infections of 203 adult patients by the viral isolation method for the diagnosis of the viral infection and transtracheal aspiration (TTA) for taking directly the specimen from the lower respiratory tract. The bronchopulmonary infections, isolated the virus, consisted of acute bronchitis (3 cases), pneumonia (8 cases) and the acute exacerbation of chronic lower respiratory infection (5 cases). The positive viral isolation consisted of Rhinovirus (11 strains), Herpes simplex virus I (3 strains), Parainfluenza virus III (1 strain) and Respiratory syncytial virus (1 stain). There were 9 transtracheal aspirates, 8 pharyngeal swabs and 5 nasal washings in the positive viral specimens. We experienced 5 cases who had the same virus isolated from both the upper respiratory tract and the lower respiratory tract. H. influenzae, P. aeruginosa and other bacteria were found in 14 of the 16 TTA cultures. These results suggest that the role of the viral infection is important either independently or relating the bacterial infection in the adult bronchopulmonary infections.

Adult↗

PubMed1994

Mechanical interdependence in relation to age: effects of lung volume on airway resistance in rats.

Elastic recoil has been reported to decrease with increasing age in human subjects. In the current study, we hypothesized that aging influences mechanical interdependence, which affects the magnitude of agonist-induced airway constriction. To examine this hypothesis, we compared the effects of changing lung volume on airway resistance (Raw) under baseline conditions and during methacholine-induced constriction in adult (14 mo old, 624 +/- 14 g; n = 11) and aged (29 mo old, 629 +/- 9 g; n = 11) Sprague-Dawley rats. With use of alveolar capsules, Raw was directly measured under baseline conditions at different levels of end-expiratory transpulmonary pressure (PL; 3-11 cmH2O). Then aerosolized methacholine was delivered (125 mg/ml), and measurements were performed at different levels of PL (3 and 11 cmH2O). From measured tracheal flow and tracheal and alveolar pressures in open-chest animals during mechanical ventilation (6 ml/kg tidal volume, 1 Hz frequency), we calculated dynamic lung elastance and resistance of lung, tissue, and airway. In the baseline conditions, we found that increasing lung volume decreased Raw similarly in both groups but that lung elastance was reduced in the aged group at PL > or = 7 cmH2O. The shape constant obtained from the pressure-volume curve in the aged rats was significantly greater than that in the adult rats. During induced constriction, higher lung volume significantly lowered Raw in the adult group, whereas Raw was not significantly reduced by increasing PL in the aged group. These observations suggest that increasing age may affect the mechanical properties of the airway and/or airway-parenchymal interdependence.

Aging↗

PubMed1994

Effect of chronic tobacco smoke exposure on the function of alveolar macrophages in mice.

We evaluated the effect of chronic tobacco smoke exposure on the function of the alveolar macrophage (AM) in mice. Tumor necrosis factor-alpha production of the AM triggered by lipopolysaccharides was smaller in smoke-exposed mice as compared to control mice but did not reach statistical significance (27.3 +/- 4.0 vs. 34.8 +/- 4.9 U/ml). The percentage of AM which did not phagocytize latex particles in the smoke-exposed mice was significantly larger than that in control mice (33.9 +/- 2.3 vs. 20.8 +/- 2.1%; p < 0.05). Ia antigen expression of the AM was significantly larger in smoke-exposed mice (cytotoxicity index: 0.180 +/- 0.033 vs. 0.038 +/- 0.0118; p < 0.01). The asialo-GM1 antigen expression was similar in both groups (0.949 +/- 0.007 vs. 0.961 +/- 0.011). Although the precise mechanisms of these functional changes of the AM by tobacco smoke exposure are not clear, they may have some immunological effects on the alveolar space.

Animals↗

PubMed1994

A novel model of senile lung: senescence-accelerated mouse (SAM).

Senescence-accelerated mouse (SAM) has been characterized as a unique animal model to investigate spontaneous aging as well as age-related disorders. However, little is known about the properties of the lung. We examined age-related morphologic and functional changes of the lung in SAM P2, as the senescence-prone strain, and in SAM R1, as the senescence-resistant strain. On morphologic examination, the earlier (starting at 6 mo) and more severe change in airspace size (mean linear intercept: MLI) was observed in SAM P2 (MLI [micron]; 3 mo: 72.1 +/- 2.4; 6 mo: 80.8 +/- 2.9; 12 mo: 91.1 +/- 3.1; 18 mo: 143.4 +/- 6.6), compared with SAM R1 (MLI [micron]; 3 mo: 68.9 +/- 1.8; 6 mo: 70.8 +/- 2.6; 12 mo: 76.1 +/- 2.8; 18 mo: 101.2 +/- 4.7). The destructive index was not remarkably changed through life in both strains, suggesting that the alveolar wall was relatively intact in SAM. On functional examination, the left-sided shift of the pressure-volume (P-V) curves observed in SAM P2 at an early stage of aging (starting at 9 mo) compared with SAM R1. The shape constant (K) obtained from the P-V curve was increased with aging in SAM P2 (K; 3 mo: 0.124 +/- 0.004; 9 mo: 0.142 +/- 0.003; 18 mo: 0.183 +/- 0.008), and also increased at a late stage of aging in SAM R1 (K; 3 mo: 0.123 +/- 0.005; 9 mo: 0.135 +/- 0.004; 18 mo: 0.148 +/- 0.007). This study demonstrates that SAM P2 manifested most of the characteristic changes in senile lung.(ABSTRACT TRUNCATED AT 250 WORDS)

Aging↗

PubMed1994

Correlation between the layer of an intimal tear and the progression of aortic dissection.

Thoracic aortas isolated from dogs were evaluated to determine the correlation between the depth of an intimal tear and the progression of aortic dissection. Thoracic aortas obtained from 99 adult mongrel dogs were used. An intimal tear (aortic pocket) was created on the aortic wall and the aorta was connected in series to a closed circuit (150 mmHg/100 mmHg and 60 beats/min). The progression of the dissection was most notable in the aortic pocket prepared in the first one-third of the external media (87.5%). There was no correlation however between the width of the pocket and the progression of dissection. Examinations of samples from surgical patients have shown that dissection usually progresses at the same site. This has been attributed to the diseased media. Our results demonstrated that dissection occurred almost always at the same site without any medial changes suggesting that whether dissection develops or not likely depends upon whether the intimal tear reaches the first one-third of the external media or not.

Aortic Dissection↗

PubMed1994

Assessment of myocardial function during mechanical left ventricular support using serial echocardiography: a case report.

A 40-year-old man with valvular heart disease was successfully treated using a left ventricular assist device (LVAD) after open heart surgery. Echocardiography revealed left ventricular ejection fraction (LV-EF) at LVAD on/off: 23.4%/14.6% on the 4th, 23.8%/23.8% on the 5th, and 23.8%/26.8% on the 6th postoperative day (POD), respectively. The patient was weaned from LVAD on the 8th POD and discharged from the hospital on the 58th POD. The LV-EF improved to 54% 6 months after surgery and increased from 57% to 64% in response to exercise stress testing 1 year after surgery.

Adult↗

PubMed1994

An experimental hemodynamic study of the pelvic collateral circulation.

Iliac arteries were occluded in adult mongrel dogs to investigate pelvic hemodynamics. When the unilateral common iliac artery was occluded, the blood flow making a "stopover" within the pelvis was found to be significantly less than that of anatomical hemodynamics even under a resting condition. The blood flow decreased more significantly under exercise loading than under a resting condition, which demonstrates the presence of the "steal" phenomenon. This only occurs in the collateral circulation in the pelvis formed by two arterial systems which are related in a series. In deciding the appropriacy of reconstruction for the internal iliac artery in patients with aorto-iliac occlusive disease, this "steal" phenomenon should be kept in mind. In most cases, ischemic symptoms in pelvic organs may be due to a simple decrease of the blood flow supplied to the pelvis, or due to the "steal" phenomenon. If the pelvic region is in the state of ischemia owing to the "steal" phenomenon, reconstruction of the blood vessels flowing into the pelvis is not required.

Animals↗

PubMed1994

[Diffuse aspiration bronchiolitis (DAB) produced in animals by repeated HCl microaspiration].

We recently reported that diffuse aspiration bronchiolitis (DAB) was detected in 1% of autopsied lungs of aged cases of pneumonia. We hypothesized whether repeated HCl micro-aspiration (RHMA) is involved in DAB and established an animal model by administering HCl intratracheally to rats every two days for 2 weeks. Saline was given to control animals in the same fashion. Then, we performed bronchio-alveolar lavage (BAL) or excised lungs for histologic examination. There was no difference in BAL cell counts, TNF alpha-production, elastase-like activity or albumin levels between the HCl and control groups. Histologically, DAB-like findings were observed in the HCl-treated animals. These data suggest that RHMA might be involved in DAB, while neither TNF alpha-production nor elastase-like activity may play a significant role in inducing DAB.

Animals↗

PubMed1994

[Improvement of post-operative activities of daily living in an aged patient with vanishing lung].

A 71-year-old male was admitted to our hospital due to progressive dyspnea. The right lung of this patient was replaced by multiple bulous lesions including giant bullae. He had severe deterioration of lung function and gas exchange. He did not complete the pre-operative examinations for thoracic surgery, but improvement in ventilatory function was expected after bullectomy. After multiple bullectomy, this case showed marked improvements in lung function and gas exchange, subsequently his dyspnea improved, as did his activities of daily living. These lung functional improvement may have resulted not only from the mechanical advantage of diaphragmatic motion due to removal of space-occupying lesion of the lung, but also from the reduction of tough fibrous adhesion between the lung and the parietal pleura which had impaired smooth lung movement. Thorough evaluation of operative indications in necessary before surgery in aged patients with lung diseases.

Activities of Daily Living↗

PubMed1994

Reduced fertility in females of the hereditary polydactyly rat.

The present studies assessed reproductive capacity of hereditary polydactyly(pd/pd) female rats that had genetically caused polydactyly in both fore- and hindlimbs. During an 8- or 10-day period of vaginal estrous cycle observation, persistent estrus was found in 30 to 39% of the pd/pd females. Although mating indices were comparable between polydactylous (pd/pd) and phenotypically normal (pd/+ or +/+) females, fertility indices were significantly decreased in pd/pd females. All impregnated pd/pd females delivered normally but had a significant decrease in the numbers of corpora lutea and pups delivered as compared with pd/+ or +/+ females. Examination of oviductal ova at 2 days after copulation revealed ovulation in only 75% of the pd/pd females and also a slight decrease in the numbers of ovulatory corpora lutea and oviductal ova in these females. In the nonovulating persistent estrus pd/pd females, the ovaries were polycystic. These results demonstrate a reduction in reproductive ability of pd/pd females.

Animals↗

PubMed1994

[Surgical treatment of pulmonary aspergillosis].

There is controversy about the optimal treatment for pulmonary aspergillosis. Eight patients with pulmonary aspergilloma underwent surgical treatment. Three patients had tuberculosis, one Sjögren syndrome, one aortitis syndrome, one malignant lymphoma. Lobectomy was performed in five patients, segmentectomy in three patients. All patients are alive and have no recurrence. We have obtained excellent results from surgery and advocate early surgery for localized lesions to prevent life-threatening hemoptysis. This will allow patients to continue with further treatment for the underlying disease. We encountered a granulocytopenic patient with rapidly progressive aspergillus infection resulting in occlusion of main pulmonary artery leading to death. Surgical intervention could not prevent this fatal outcome. The selection of the patients with diffuse lesions should be made carefully.

Adult↗

PubMed1994

[A case of multiple myeloma associated with a large subcutaneous mass in the frontal region].

A case of multiple myeloma having plasmacytoma in the frontal bone and clivus is reported. A 68-year-old female was referred to our hospital because of a subcutaneous mass in the frontal region. She was diagnosed as having multiple myeloma 7 years ago and had been treated with chemotherapy. On admission, severe anemia, hyperproteinemia and elevation of serum lambda type immunoglobulin G (IgG) were pointed out. Plain skull X-rays showed numerous punched out lesions with a large bone defect of the frontal bone. CT scan and MRI revealed a mass lesion in the clivus in addition to a large epidural tumor in the frontal region. The encapsulated frontal epidural tumor was totally resected and cranioplasty was performed with resin. Histological diagnosis was plasmacytoma of IgG lambda type. The postoperative course was uneventful, and chemotherapy was continued. There was no tumor recurrence in the frontal region and no neurological deterioration, but she died of DIC 15 months after the operation. Twenty seven cases in the literature of multiple myeloma forming cranial or intracranial plasmacytoma were briefly reviewed. Although the prognosis of such cases is poor, total resection of medullary plasmacytoma is warranted especially in multiple myeloma patients who don't have another extramedullary plasmacytoma or plasma cell leukemia.

Aged↗

PubMed1993

Prognosis of undetected intrapulmonary metastases in resected lung cancer.

BACKGROUND: Between 1975 and 1989, 839 patients with lung cancer underwent pulmonary resection at Okayama University Medical School; for this study data of the 42 (5.0%) who had intrapulmonary metastasis were analyzed. RESULTS: The 5-year survival rate for the 42 patients was 25.7%, which was significantly better than that of patients with Stage IV disease and extrapulmonary metastasis, none of whom survived for 3 years. The 2-year survival rate was found to be significantly better in patients with one-lobe metastasis (n = 37; 41.5%) than in those with two-lobe metastasis (n = 5; 20.0%). Adenocarcinoma was the most common tumor (66.8%), followed by squamous cell carcinoma (28.6%), but the prognosis differed little between these two histologic types. Intrapulmonary metastasis did not unfavorably affect the prognosis when the primary tumor was 3 cm or less in greatest dimension and there were no lymph node metastases (T1N0). CONCLUSION: In patients with lung cancer and one-lobe intrapulmonary metastasis, particularly in those with T1N0, a favorable prognosis can be expected after surgery.

Adenocarcinoma↗

PubMed1993

An experimental study on spinal cord ischemia during cross-clamping of the thoracic aorta: the monitoring of spinal cord ischemia with motor evoked potential by transcranial stimulation of the cerebral cortex in dogs.

The usefulness of spinal motor evoked potential by transcranial stimulation of the motor cortex (MEPT) in detecting spinal ischemia and predicting postoperative neurological dysfunction was evaluated using a model of spinal ischemia. Group 1 was comprised of 11 dogs used for measuring the basic wave form of spinal MEPT. The normal spinal MEPT response curve consists of two major peaks: peak I and peak II. The latency of peak I and peak II at T13-L1 was 6.0 +/- 0.6 and 7.1 +/- 0.6 msec, and the amplitude, 3.3 +/- 1.6 and 6.1 +/- 2.6 microV, respectively. Group 2 was comprised of six animals subjected to spinal ischemia, in which a time-related deterioration of the MEPT as well as evoked spinal cord potential (ESP) was demonstrated. The time taken until the loss of peak I and peak II was 19.2 +/- 5.3 and 21.7 +/- 6.2 min, respectively, while the time taken until the loss of ESP was 36.7 +/- 14.0 min. In group 3, comprised of seven animals, the aorta was unclamped and the animals were allowed to recover when the spinal MEPT had disappeared. Four had paraparesis immediately after the operation, two had a normal gait, one died, and one developed spastic paraplegia after 24 h. We concluded that the change in spinal MEPT during spinal ischemia occurred earlier than the change in ESP, and that the loss of MEPT suggested irreversible spinal cord damage.

Animals↗