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Biomedical subjects

T Kawashiro

Publications and source records attributed to T Kawashiro.

At least 73 records · Page 4Linked to original sources

[Standard values and normal limits for arterial blood gases in healthy elderly Japanese subjects].

We studied the standard values and normal limits for arterial blood gases in healthy elderly Japanese subjects. The criteria for inclusion were; 1) older than 60 years and able to walk independently, 2) non-smoker, 3) no respiratory symptoms, 4) no thoracic deformity, 5) no clinical signs of chest disease, 6) no abnormal findings in chest X ray, and 7) no cardiac disease or obesity. The number of subjects was 78. The oldest subject was a 96-year-old female. Arterial punctures were performed with the subjects in a recumbent position. PaO2 ranged from 79 to 106 Torr, with a mean value of 89.8 Torr. PaCO2 ranged from 32 to 48 Torr with a mean value of 39.6 Torr. Maximum values of alveolar-arterial O2 tension difference and arterial-alveolar N2 tension difference were 20.2 Torr and 11.6 Torr, respectively. The regression equation for PaO2 with respect to age was; PaO2 = 99.32-0.126 x (age), and its residual standard deviation was 6.06 Torr. These values were not different from those obtained in healthy young Japanese subjects.

Aged↗

[Uneven ventilation-perfusion ratio distribution during acute exacerbation of chronic pulmonary diseases].

We studied ventilation-perfusion ratio (VA/Q) unevenness in terms of alveolar-arterial gas tension difference (AaDO2 and aADN2) and of multiple inert gas elimination technique during the chronic stable periods and the acute exacerbation periods of seven cases with chronic pulmonary diseases. Three had idiopathic pulmonary fibrosis, 2 had pulmonary emphysema, 1 had bronchiolitis and the other had a sequelae of pulmonary tuberculosis. Sulfur hexafluoride and cyclopropane dissolved in saline were infused into a peripheral vein at a constant rate and these 2 gases were used as the indicator gases to make analysis of two compartmental VA/Q. During exacerbation all cases showed lower PaO2 than in the stable period. All cases except idiopathic pulmonary fibrosis showed higher PaCO2. Five cases also had higher AaDO2 and aADN2. One case with pulmonary emphysema and one with bronchiolitis actually had lower AaDO2 and aADN2 values during acute exacerbation than during the chronic stable period. We introduced the difference between the logarithm of higher VA/Q and lower VA/Q values (log [(VA/Q)H/(VA/Q)L)] as an index of VA/Q unevenness. Two compartmental VA/Q analysis revealed greater VA/Q differences in all cases during acute exacerbation. This included cases who showed lower AaDO2 and aADN2 values in the acute exacerbation period. In conclusion, worsened VA/Q distribution, during the acute exacerbation period, was elucidated quantitatively using the multiple inert gas elimination technique.

Adult↗

[Usefulness of vitamin A binding protein as a marker for capillary endothelial permeability].

We performed a preliminary study to assess the usefulness of Vitamin A binding protein (VABP) as a gamma-camera marker for capillary endothelial permeability. We used a guinea pig model of endotoxin (LPS) induced acute lung injury. We calculated the concentration ratio of either 125I-albumin or 125I-VABP in lung tissue to that in plasma (tissue plasma ratio; T/P) as a parameter of capillary endothelial permeability. 99mTc-diethylene triamine pentaacetic acid (DTPA) was used as a marker for pulmonary interstitial volume. We estimated wet to dry lung weight ratio as a parameter of lung water accumulation (W/D). LPS increased the T/P of 125I-albumin and W/D, suggesting the development of permeability edema. The T/P for 125I-VABP was also increased, indicating that 125I-VABP can be used to detect elevated capillary endothelial permeability. In both groups, LPS and saline, the T/P was higher for 125I-VABP than for 125I-albumin. These data suggest that the pulmonary capillary endothelium is more permeable to VABP than albumin.

Animals↗

Distribution of ventilation and of diffusing capacity to perfusion in the lung.

We developed a method for estimating the distribution of ventilation (VA) and of diffusing capacity (G) to perfusion (Q) in the lungs. We used O2, CO2 and CO together with six inert gases of widely differing solubility and assumed that mass transfer efficiency of each gas in a gas exchange unit is limited by both VA/Q and G/Q ratios. The underlying lung model comprised 20 units along both the VA/Q and G/Q axes. Using numerical analysis, we transformed the data into a virtually continuous distribution of Q in the VA/Q-G/Q field. We tested the precision of the numerical procedure by examining the recovery of various artificial distributions, and found that distributions with up to two modes could be recovered with reasonable accuracy. Analytical results from 15 patients with interstitial pneumonia of unknown etiology (IPF) revealed the following features. (1) In an early disease stage, most of the lung was operating in the range of normal VA/Q, without a significant contribution of diffusion limitation. (2) An advanced stage of the disease exhibited a widening of VA/Q distribution and either broad unimodal or bimodal distribution of G/Q, extending to G/Q below 10(-3) ml (STPD)/(ml.Torr) with diffusion-limited O2 exchange. (3) Severe diffusion limitation causing disequilibrium of inert gas across the blood-gas barrier was observed in three (far advanced fibrosis; active interstitial inflammation) out of 15 patients. These findings suggest that inhomogeneity of G/Q does exist and may play an appreciable role in causing impairment of gas exchange in patients with interstitial pneumonia.

Animals↗

[A case of Legionnaires' disease cured with a combination of erythromycin and steroid therapy].

A 53-year-old male was admitted to Keio University Hospital with a pneumonia shadow in the left lung field and respiratory failure. Because there was progression of respiratory failure, mechanical ventilation was required to maintain appropriate oxygenation. Although erythromycin administration was started at the time of admission, a steroid (prednisolone 60 mg/day) was added a few days later to temporarily inhibit the acute inflammatory response in the lung parenchyma. This intensive therapy resulted in resolution of the patient's pneumonia and improvement of his respiratory failure. No pathogens were detected in the clinical specimens. Indirect immunofluorescence examination demonstrated a marked increase in titers against Legionella pneumophila serogroup 1, which was sufficient to confirm a diagnosis of Legionnaires' disease. The causative organism of this disease, a gram-negative short rod, is rarely cultured on conventional culture media. Two clinical subtypes are known based on clinical manifestations: 1) the Pontiac fever-type in which the predominant symptom is fever alone; and 2) the pneumonia-type which was observed in the epidemic in Philadelphia when the disease was first reported in 1976. The present case of Legionnaires' disease was the severe pneumonia-type which was successfully treated with a combination of erythromycin and a steroid.

Drug Therapy, Combination↗

[Changes in sound transmissibility through the canine thorax due to the experimental pleural effusion].

The authors studied the effects of pleural effusion on sound transmissibility through the canine thorax. In the supine position, dogs received sound ranging from 100 to 1000 Hz at the tracheostoma. Using the microphones attached to the dorsal and ventral part of the chest wall, the relative level of the transmitted sound wave was determined in reference to the amplitude of the sound wave at a tracheostom. Measurements of sound transmissibility were performed before and after injecting saline into the bilateral pleural space which was intended to be experimental pleural effusion. In the dorsal part, the experimental pleural effusion decreased sound transmissibility in the frequency range between 100 and 300 Hz. At 100 Hz, the pleural effusion of 5, 10, and 15 ml/kg/hemithorax caused a decrease in sound transmissibility by 3.7 +/- 3.7, 6.6 +/- 4.9, and 10.0 +/- 5.7 dB, respectively. In the ventral part, the reduction in sound transmissibility in the low frequency range due to the pleural effusion was small. In contrast, introduction of pleural effusion caused an increase in sound transmissibility by 5 to 9 dB in the frequency range above 500 Hz. We consider that these changes in sound transmission are implicated in the physical findings such as "aegophony" and reduction in vocal fremitus or vocal ausculation.

Animals↗

[Two cases of primary lung cancer with initial symptoms due to ocular metastases].

Two cases of primary lung cancer with initial symptoms due to metastasis to the eye or the orbit are reported. Case 1 had orbital metastasis, while case 2 had intraocular metastasis. It has been reported that the survival period is short after the metastasis was found. In our cases, the survived periods for case 1 and case 2 were 3.5 months and one month, respectively.

Adenocarcinoma↗

[Characteristics of impaired gas exchange in patients with chronic obstructive pulmonary disease].

Eleven patients with chronic obstructive pulmonary disease (COPD), placed in a supine position, were given a mixture of 0.1% CO and 21% O2 in N2 as inspired gas and normal saline containing the six inert gases including SF6, ethane, cyclopropane, halothane, diethyl ether and acetone via the antecubital vein. After the steady state was established, the expired gas was collected and both arterial and mixed venous blood were simultaneously sampled through the catheter inserted either into the femoral or pulmonary artery. Assuming that mass transfer efficiency of a given indicator gas at each gas exchange unit would be limited by the ratio of ventilation to perfusion (VA/Q) and by that of diffusive conductance to perfusion (G/Q), the data were analyzed by means of a lung model with 20 units along the VA/Q and G/Q axes, respectively. By application of the method of weighted least-squares combined with the idea of constrained optimization, the data were transformed into a virtually continuous distribution of Q against VA/Q and G/Q axes. Analytical results revealed that: 1) patients with advanced COPD show widening of VA/Q distribution accompanied with a significant contribution of either high VA/Q (emphysematous change) or low VA/Q area (peripheral airway involvement). and 2) their Q distributions along the G/Q axis are unimodal but have an area with a relatively low G/Q, indicating a small but appreciable contribution of diffusion limitation to their hypoxemia. In conclusion, the findings consistently suggest that inhomogeneity of G/Q may partly be responsible for the impaired gas exchange in the cases of COPD.

Humans↗

Estimation of the distribution profile of airway resistance in the lungs.

The distribution profile of resistance in a series lung model consisting of airways of 23 generations with alveoli was estimated in 10 healthy subjects and 7 subjects with chronic pulmonary emphysema. Forced oscillation was applied to the subjects at the mouth using a complex wave composed of sine waves at frequencies through the range 4 to 20 Hz in 1-Hz steps. The pleural pressure was measured with a catheter-tip micromanometer, which was installed in an esophageal balloon. The frequency dependency of the pulmonary impedance was analyzed using a penalty function method, and a stable estimate of the distribution profile of resistance in the lungs was thus obtained. The central airway resistance (defined as the resistance from generation 0 to generation 7) was estimated as 1.18 +/- 0.37 cm H2O/liter/sec in the healthy subjects and 1.03 +/- 1.13 cm H2O/liter/sec in the subjects with chronic pulmonary emphysema. The peripheral airway resistance (defined as the resistance from generation 8 to generation 23) was estimated as 0.06 +/- 0.03 cm H2O/liter/sec in the healthy subjects and 6.38 +/- 3.77 cm H2O/liter/sec in the subjects with chronic pulmonary emphysema.

Adult↗