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H Tazawa

Publications and source records attributed to H Tazawa.

At least 91 records · Page 5Linked to original sources
PubMed1989

[Total replacement of the urinary bladder using an ileal pouch bladder].

We have used the continent ileal bladder as a bladder replacement after radical cystectomy. The ileal bladder is an ileal pouch which is anastomosed to the urethral stumps. The ureters are implanted by a free end ureteroileostomy. The long term results with 26 patients who underwent this procedure are reported. In the early postoperative period, urodynamic and radiographic studies revealed small capacity and high intravesical pressure of the ileal bladder. However, it became a low pressure reservoir with increased capacity gradually. The average bladder capacity was about 250 ml and average residual urine was 30 ml. Most of the patients were continent in the daytime if the voiding intervals were less than 3 hours at night, some patients were incontinent. Urinary leakage was the most frequent complication. VUR and hydronephrosis were still the problems to be solved. The ileal pouch bladder is a valuable procedure in properly selected cases.

Adult↗
PubMed1989

[A case of acute retinal necrosis syndrome caused by herpes simplex virus type 1].

A case of bilateral acute retinal necrosis syndrome accompanied by viral meningitis in a 46 year-old male is reported. The characteristic scattered yellowish-white retinal exudates and retinal detachment appeared in both eyes within 2 weeks, and after treatment with intravenous acyclovir and gamma-globulin, and encircling, scleral buckling, pars plana vitrectomy, 100% SF6 tamponade procedures, the retinal detachment was repaired and the yellowish-white retinal exudates disappeared. On virological examination, the complement fixation titer for herpes simplex virus (HSV) in serum increased more than eightfold in pair serum, and the quotient of antibody for HSV type 1 (HSV-1) IgG was high. HSV-1 was isolated and cultured from the subretinal fluid. From these results, it is concluded that HSV-1 infection was the cause of the meningitis and acute retinal necrosis in this case.

Acute Disease↗
PubMed1989

[Microbiological and pharmacokinetic studies on flomoxef in ophthalmologic field].

Microbiological and pharmacokinetic studies were carried out on flomoxef (FMOX, 6315-S), a new oxacephem parenteral antibiotic, in the ophthalmologic field. The results obtained are summarized as follows. FMOX has a broad antimicrobial activity spectrum against Gram-positive and Gram-negative bacteria. The MIC distribution against Staphylococcus aureus isolated from clinical cases was less than or equal to 0.20 - greater than or equal to 100 micrograms/ml with the peak value of 0.39 micrograms/ml. Concentrations of FMOX in aqueous humor and ocular tissues were determined after intravenous injection of 50 mg/kg to rabbits. FMOX showed a peak level of 2.2 micrograms/ml in the aqueous humor at 1/2 hour after administration with the ratio to serum level of 3.4%. Levels of FMOX in external and internal ocular tissues were 12.7 - 76.5 micrograms/g, less than 0.8 - 34.4 micrograms/g (ml) at 1/2 hour after administration, respectively. From these results, we concluded that FMOX may be expected to be a useful and valuable agent against infections in the ophthalmologic field.

Animals↗
PubMed1988

The analysis of PO2 difference between air space and arterialized blood in chicken eggs with respect to widely altered shell conductance.

The gas exchange of chicken eggs takes place by molecular diffusion. The diffusion barrier between ambient atmosphere and erythrocyte hemoglobin of the gas exchanger (the vascularized chorioallantoic membrane) is conveniently divided into two parts by the air space in the fibrous shell membranes; i.e., the outer barrier (mainly the porous eggshell) and the inner barrier (the chorioallantoic membrane and the chemical reaction with hemoglobin). In contrast to the alveolar-arterial Po2 difference in vertebrate lungs, the difference of Po2 between the air space and the arterialized blood in the allantoic vein (delta PAo2.Pao2) is large in chick embryos. The present study analyzed the delta PAo2.Pao2 in relation to the diffusing capacity of the chorioallantoic membrane (inner barrier) and physiological shunt in the allantoic circulation with respect to widely altered diffusive conductance of the shell (outer barrier). The shell diffusive conductance (Go2) was altered of the beginning of incubation, and the O2 consumption (Mo2) was measured on day 16. The Mo2 increased hyperbolically with increasing Go2, reached a maximum at control values of Go2 and decreased with further increases in Go2. From Go2 and Mo2, the air space Po2 was determined. The delta PAo2.Pao2 was increased in eggs with augmented Go2 (from about 50 torr in control eggs to 70 torr in conductance-increased eggs). The diffusing capacity and allantoic shunt which produce a given delta PAo2.Pao2 were estimated employing a microcomputer performing the Bohr integration procedure so that a calculated Pao2 agreed with the measured Pao2. The allantoic shunt is not more than 20%; 10% is likely. The diffusing capacity becomes maximum in intact control eggs and is decreased at both lowered and augmented Go2. At lowered Go2, diffusion limitation is responsible for about 90% of delta Pao2.Pao2 even in the presence of a 10% shunt. The diffusion limitation to blood oxygenation decreases as Go2 increases, but it is still predominant at augmented Go2. In control eggs, the resistance of the inner barrier to O2 diffusion is about 1.7-fold that of the shell (outer barrier) which agrees with the previous reports.

Animals↗
PubMed1988

A blood-gas nomogram of the chick fetus: blood flow distribution between the chorioallantois and fetus.

This paper presents equations for quantifying the relationships between the O2 and CO2 concentrations and tensions in the blood of the 18-day chick fetus. A blood-gas nomogram showing these relationships is presented. Starting with the reported chorioallantoic artery and vein gas tensions and using the blood-gas equations, the range of embryonic arterial and venous gas tensions as well as the distribution of the cardiac output and the degree of mixing between the chorioallantoic and embryonic circulations are explored. It is concluded that at least 65% of the blood in the chorioallantoic artery consists of blood of embryonic mixed venous composition. A model of the blood flow distribution is proposed in which chorioallantoic and embryonic flows are equal, with 70% of the blood returning from the tissues of the embryo going to the chorioallantois and vice versa.

Allantois↗
PubMed1988

Gas exchange and development of chicken embryos with widely altered shell conductance from the beginning of incubation.

The O2 uptake of chicken embryos confined in the eggshell (MO2) is governed by a shell diffusive conductance (GO2) and PO2 difference between ambience and air space, suggesting that a relation between GO2 and air space PO2 (PAO2) is hyperbolic at constant MO2. Upon wide alteration of GO2 from the beginning of incubation, the MO2 was measured on day 16 of incubation and the relation between GO2 and PAO2 examined. The MO2 increased hyperbolically with increasing GO2, reached maximum at control conductances and decreased with further increase in GO2. From these changes in MO2 with GO2, an equation was derived predicting PAO2 as a quadratic function of inverse gO2 (mass-specific conductance, i.e., GO2 standardized by fresh egg mass), and the relation between air space PO2 and shell conductance was no longer hyperbolic. The arterialized blood PO2 (PaO2) of the allantoic vein measured individually was also expressed by a quadratic equation of inverse gO2. While for widely altered conductance the MO2 was little related to PaO2, the mass (embryo)-specific O2 uptake increased with PaO2. The excess water loss associated with increased conductance was involved in changes in these variables.

Animals↗
PubMed1988

Short-term effects of altered shell conductance on oxygen uptake and hematological variables of late chicken embryos.

The preceding report on the O2 uptake (MO2) of chicken embryos whose shell conductance (GO2) was altered from the beginning of incubation showed that the MO2 was decreased despite increased GO2 [Okuda, A. and H. Tazawa (1988) Respir. Physiol. 74: 187-198]. This was attributed to an excess water loss which reduced the growth of the embryos. The present study was designed to investigate the short-term effects of altered GO2, obviating the effect of excess water loss, on the MO2 and simultaneously on the hematological variables of embryos on days 16-17 and days 18-19 of incubation. The MO2 measured 5 h after increasing the GO2 was neither decreased nor increased significantly. The diffusing capacity of the chorio-allantoic membrane, which was estimated using the Bohr integration procedure, decreased as the GO2 was increased. When the GO2 was decreased, on the other hand, the decrease in MO2 was not so large as expected from the decrease in GO2, for both 16- and 18-day-old embryos. The effect of reduced GO2 on MO2 was more prominent in 18-day-old embryos than 16-day-old embryos. One-day-long hypoxia due to decreased GO2 induced erythropoiesis in 18-19-day embryos, but did not do so in 16-17-day embryos. The increase in hematocrit value of the latter group of embryos was attributed to an increase in cell volume due to concurrent hypercapnia.

Allantois↗
PubMed1988

Cooling rates of living and killed chicken and quail eggs in air and in helium-oxygen gas mixture.

1. In a helium atmosphere, heat is dissipated from a surface 3.5 times faster than it is in air. Eggs in a helium-oxygen atmosphere cool only 1.4 times faster than they cool in air. This signifies that internal resistance to heat flow is a significant factor in the cooling rates of eggs. 2. Heat flow occurs inside an egg in two ways: by conduction through the tissues and in flowing blood. Killing an embryo stops the latter, but not the former. Eggs cool more slowly after they have been killed, signifying that blood flow can be an important component in an egg's internal flows of heat. 3. Blood flow should be a relatively more important component of heat flow in large eggs than in small eggs. The difference in conductance between living and killed eggs is larger in 60 g chicken eggs than it is in 10 g quail eggs.

Animals↗
PubMed1987

Comparative model analysis of central shunts in vertebrate cardiovascular systems.

The incomplete double circulation of air-breathing fishes and lungfishes, amphibians, reptiles and embryonic birds and mammals has been analyzed using a simplified mode comprising the intra- and extracardiac shunts and compartments for the gas exchange (gills, lungs, skin, etc.) as well as systemic tissue gas exchange. The intracardiac shunting is defined and given common symbols for all species of animals analyzed. Two types of equations, fluid-flow and mass-flow equations, are derived for each model, which are solved to give shunting rate as a function of blood O2 content of the principal cardiac compartments and vessels. The model analysis not only offers possibility for an overall average evaluation of central shunts, but also suggests which blood samples must be determined for evaluation of the shunt patterns.

Animals↗
PubMed1987

A case of recurrent malignant pheochromocytoma complicated by watery diarrhea, hypokalemia, achlorhydria syndrome.

A patient is reported who had undergone right adrenalectomy for pheochromocytoma and 15 yr later developed a recurrence in the same site complicated by the watery diarrhea, hypokalemia, achlorhydria syndrome. This tumor was histologically defined as a composite malignant pheochromocytoma-ganglioneuroblastoma (well differentiated type). Vasoactive intestinal polypeptide and catecholamine concentrations were elevated in both plasma and the tumor. The tumor somatostatin content also was high. The tumor was immunohistochemically determined to contain both vasoactive intestinal polypeptide and somatostatin.

Achlorhydria↗
PubMed1987

[Clinical study of cefotetan in complicated urinary tract infections].

Clinical effectiveness and safety of Cefotetan were evaluated in 28 patients with complicated urinary tract infections. The results were excellent in 12 patients (42.9%), moderate in 10 patients (35.7%) and poor in 6 patients (21.6%), and the effectiveness rate was 78.6%. Bacteriologically, 24 (75%) out of 32 strains were eradicated. Subjective side effects, nausea and abdominal discomfort, were observed in one patient. Abnormal laboratory findings were observed in 6 patients, eosinophilia in 3 patients and slight elevation of transaminase in 3 patients.

Adult↗
PubMed1987

Temperature and metabolism of chick embryos and hatchlings after prolonged cooling.

Is a new quasiequilibrium state of metabolism and egg temperature reached after chick embryos and hatchlings are exposed to prolonged cooling? During the last half of the incubation period the chicken egg maintains a temperature above that of the ambient air temperature of 38 degrees C. This difference increases from about 0.2 degree C at 11 days to 2 degrees C just before hatching and to 3 degrees C by 7 days posthatching. When eggs or hatchlings are then exposed to room air at 28 degrees C, a new quasiequilibrium state is reached in 5 hr (defined as a change in egg temperature of less than 0.1 degree C X hr-1). The new difference between egg and ambient temperature varies from about 0.1 degree C at 11 days to 1.2 degrees C just before hatching, but increases in the hatchling from 6 degrees C right after hatching to 10 degrees C 5 days later. During the quasiequilibrium state at 24 degrees C the metabolic rate is maintained at about 40% of the control value up to hatching time, but thereafter rapidly increases to 70-95% by day 1. In a few cases emergence from the shell was not necessary for increases in quasiequilibrium temperature and metabolic rate.

Animals↗
PubMed1986

Tolerance of chick embryos to low temperatures in reference to the heart rate.

Ten-day-old embryos were exposed to 28, 18 and 8 degrees C environments and their electrocardiograms (ECG) monitored. Embryos in 28 and 18 degrees C environments maintained a constant heart rate averaging 97 and 25 beats/min, respectively, followed by arrhythmias and cardiac arrest at 101 and 59 hr. Embryos in an 8 degrees C environment went into cardiac arrest after 2-4 hr, but recovered 20 hr later upon rewarming to 38 degrees C. Six to 20-day-old embryos exposed to 8 degrees C were examined for tolerance time after cardiac arrest. The younger the embryo the longer its tolerance to prolonged cardiac arrest.

Acclimatization↗
PubMed1986

The problems of digitalis therapy from the viewpoint of serum concentration with special reference to the sampling time, to the overlapping range of serum concentration where intoxicated and non-intoxicated patients are located and to atrial fibrillation.

Clinical studies were carried out during digoxin maintenance therapy to clarify three questions concerning digitalis therapy: optimal time for blood sample collection for serum digoxin concentration (SDC), the overlapping range of SDC levels in which some patients may be intoxicated while others are not, and both resistance and sensitivity of atrial fibrillation (AF) to digitalis. The SDC curve after a single dose of digoxin or beta-methyldigoxin shows the appropriate sampling time to be at least 12 hours after the administration. The optimal time is 24 hours. The overlapping SDC range was 1.7-2.7 ng/ml. There were significant differences in CTR and ventricular rates in AF between intoxicated and non-intoxicated groups. This suggests that susceptibility to digitalis increases with the severity of underlying heart disease. Precipitating factors such as CTR should be taken into consideration, if the SDC is in the overlapping level. Digitalis resistance occurs in 6.7% of 105 patients with AF, and more frequently in hypertensive heart disease than others. Digitalis sensitivity occurs more often in the elderly and in patients with dilated cardiomyopathy. But it is not necessary to attain higher therapeutic levels for AF than for sinus rhythm. Clearly optimal digitalis therapy for AF can be best accomplished when precise clinical findings, SDC and EKG recordings are carefully monitored and used to correct treatment.

Adult↗