Search PubMed⌕ Search

Biomedical subjects

T Sawa

Publications and source records attributed to T Sawa.

At least 127 records · Page 7Linked to original sources

The effect of the partial pressure of oxygen on blood glucose concentration examined using glucose oxidase with ferricyan ion.

Glucose oxidase with ferricyan ion (GOD-F) is widely applied in clinical settings as a glucose sensor. However, blood oxygen concentration affects this blood glucose value because oxygen, at increased concentrations, consumes blood glucose, which cannot then be measured by this sensor. We investigated the effect of PO2 on blood glucose concentration in 48 patients who were breathing high concentrations of oxygen. Arterial and pulmonary arterial blood glucose values were analyzed using the GOD-F method and, as a control, the hexokinase method. The respective PO2 values were also measured. The blood glucose concentrations measured by the GOD-F method show a significant linear relation with that measured by the hexokinase method in both arterial (y = -24.4 + 1.01x, r = 0.99) and pulmonary arterial blood (y = -3.4 + 1.01x, r = 0.96). The difference of intercepts is statistically significant, but because of the relatively large limits of agreement indicating any hidden extraneous variabilities, the error of the GOD-F method could not be assessed just by the difference. The equation defining the effect of PO2 on the percent change between blood glucose measured by the GOD-F method and that measured by the hexokinase method is -19.8/(1 + 203900/PO2(2.68) (r = 0.62). This formula generally follows our measured materials and introduces the relationship among blood glucose value, PO2, and the error of the GOD-F method. We hesitate to suggest that the arterial blood glucose concentration when measured by the GOD-F method could be underestimated by as much as 20% in patients with high arterial oxygen pressure.(ABSTRACT TRUNCATED AT 250 WORDS)

Anesthesiology↗

Aldecalmycin, a new antimicrobial antibiotic from Streptomyces. I. Taxonomy, fermentation, isolation, physico-chemical and biological properties.

A new antibiotic, aldecalmycin, has been discovered in the culture broth of Streptomyces sp. MJ147-72F6. Aldecalmycin was purified by solvent extraction, Diaion HP-20 chromatography, silica gel chromatography, Sephadex LH-20 chromatography, HPLC and centrifugal partition chromatography. The 1H and 13C NMR spectra of aldecalmycin showed the presence of keto-enol tautomers. Aldecalmycin is equipotent in inhibiting the growth of sensitive and methicillin-resistant Staphylococcus aureus (MRSA).

Anti-Bacterial Agents↗

Aldecalmycin, a new antimicrobial antibiotic from Streptomyces. II. Structure elucidation by NMR studies.

A new antibiotic, aldecalmycin (1) was isolated from the culture broth of Streptomyces sp. MJ147-72F6. The 1H and 13C NMR spectra of 1 were complicated due to the presence of a beta-ketoaldehyde moiety. Therefore, 1 was converted into an ethylene ketal derivative (2) and into a dihydroaldecalmycin (3). These derivatives gave assignable NMR spectra. The planar structure was elucidated by using 1H-1H COSY, 2D-HOHAHA, 1H-13C COSY and HMBC spectra of 2. The conformation of the decalin ring was elucidated by using ID-HOHAHA, NOE difference and NOESY spectra of 3. The geometry of double bond in the side chain was determined by NOE difference and NOESY spectra of 3.

Anti-Bacterial Agents↗

Biosynthesis of antitumor antibiotic, cytogenin.

The biosynthesis of antitumor antibiotic cytogenin, 3-hydroxymethyl-6-methoxy-8-hydroxy-isocoumarin, was studied by feeding 14C- or 13C-labeled compounds to culture of the producing organism, Streptoverticillium eurocidicum MI43-37F11. 14C-Acetate and 14C-methionine were efficiently incorporated into cytogenin as precursors. 13C NMR studies proved that the carbon skeleton of cytogenin is derived from pentaketide intermediate due to head-to-tail condensation of five acetate units and methyl group of 6-OCH3 is derived from methionine. It was suggested that 3-hydroxymethyl and/or 6-methoxy group of cytogenin were metabolized by hydroxylation and/or methylation from three intermediates.

Acetates↗

Antitumor effect of piericidin B1 N-oxide.

Piericidin B1 N-oxide was isolated from a culture broth of Streptomyces sp. as a novel inhibitor of phosphatidylinositol (PI) turnover. Piericidin B1 N-oxide specifically inhibited orthophosphate labeling of PI induced by epidermal growth factor (EGF) without affecting the formation of phosphatidic acid (PA). Like piericidins A1 and B1, piericidin B1 N-oxide inhibited ATP synthesis in A431 cells; however, the effect of piericidin B1 N-oxide on PI synthesis was stronger than that of piericidins A1 and B1. At the concentration inhibiting PI synthesis, piericidin B1 N-oxide showed no inhibitory effect on DNA, RNA, or protein synthesis. We also demonstrated that piericidin B1 N-oxide reversibly inhibited the growth of A431 cells in situ and suppressed the growth of Ehrlich carcinoma in vivo when administered to mice by intraperitoneal (ip) injection.

Adenosine Triphosphate↗

Changes in muscle and liver lactate concentrations after endotoxin infusion in rats.

The interstitial lactate concentration in rat skeletal muscle and liver was measured using a microdialysis method during the early stage of endotoxemia and during lactic acid infusion. The lactate concentration in the muscle and liver interstitium never exceeded the blood lactate concentration throughout the 180 min period after endotoxin administration. The present findings also showed that the muscle and liver interstitial lactate concentration gradually increased in endotoxin-infused animals compared to that in lactic-acid infused animals, although the blood lactate concentration in lactic acid-infused animals was the same as that in endotoxin-infused animals. These findings suggest that the skeletal muscle and liver may consume lactate in an endotoxemic condition. However, the capacity of lactate consumption in the skeletal muscle might gradually decrease after endotoxin administration, although that in liver might be well preserved.

Animals↗

A new surgical technique (left upper abdominal evisceration) for advanced carcinoma of the gastric stump.

In spite of recent advances in the early diagnosis of gastric cancer by mass screening, gastric stump cancers following gastrectomy are still diagnosed at a highly advanced stage, and the surgical results remain very poor. Involvement of the fourth level lymph node stations, local peritoneal carcinomatosis and tumor growth invading the neighboring organs are frequently observed in advanced stump cancers. With the aim of achieving complete resection of these tumors, left upper abdominal evisceration (LUAE) + R4 gastrectomy was performed in 29 patients (Group B) with stump cancer as a radical surgical procedure. The survival of these patients was compared with that of 74 patients (Group A) who underwent total gastrectomy with or without pancreaticosplenectomy. Duration of surgery blood loss, and incidence of postoperative complications were similar with the two methods. When the survival rates were compared, the 5-year-survival rate in stage IV cases was higher for Group B than for Group A. LUAE + R4 gastrectomy is a rational technique for the surgical treatment of stage IV gastric stump cancer.

Adrenalectomy↗

Effect of urea concentration on the base-specific separation of oligodeoxynucleotides in capillary affinity gel electrophoresis.

Base-specific separations of oligodeoxynucleotides were achieved with high resolution by electrophoresis, using a urea-gel capillary, in which poly(9-vinyladenine) (PVAd) was utilized as an affinity ligand. The migration behaviour and the plate number of oligodeoxynucleotides were investigated as a function of urea concentration between 2 and 10 M in capillary gel electrophoresis (CGE) as well as capillary affinity gel electrophoresis (CAGE). The migration time in CGE separation increases as urea concentration increases. An increase in the viscosity of the gel buffer medium as well as a change in the conformation of oligodeoxynucleotides is found to be a predominant factor for an increase in the migration time. The migration time and the plate number of oligothymidylic acids, which interact with PVAd in CAGE, is manipulated by differing urea concentration, which leads to the change in the dissociation process of a specific hydrogen bonding between oligothymidylic acids and PVAd. The migration time of oligodeoxyadenylic acids, which do not interact with PVAd in CAGE, increases with an increase in urea concentration as in CGE separation. The plate number of oligodeoxyadenylic acid was not affected by the urea concentration.

Adenine↗

Extravascular lung water measured with 99mTc-RBC and 99mTc-DTPA is increased in left-sided heart failure.

Extravascular lung water (EVLW) was quantitatively measured in 81 patients consisting of 10 subjects with normal cardiac function and 71 patients with left-sided heart diseases, using 99mTc-RBC as a non-diffusible indicator and 99mTc-DTPA as a diffusible indicator in the equilibrium phase. EVLW averaged 3.0 +/- 1.4 (ml/kg, mean +/- SD) in subjects with normal cardiac function (n = 10), 4.3 +/- 1.7 in New York Heart Association functional class I patients (n = 30), 4.8 +/- 2.4 in NYHA functional class II patients (n = 33) and 9.4 +/- 5.4 in NYHA functional class III (n = 8) patients. EVLW was greater in NYHA class III than in normal controls or NYHA classes I or II (p < 0.01). Lung thermal volume (LTV) was also measured in 31 of the 81 patients using a double indicator dilution technique with sodium and heat. LTV averaged 6.0 +/- 1.2 (ml/kg) in normal subjects (n = 4), 8.6 +/- 2.0 in NYHA functional class I patients (n = 11), 9.7 +/- 3.0 in NYHA functional class II patients (n = 13), and 15.9 +/- 8.2 in NYHA functional class III patients (n = 3). The correlation between EVLW and LTV was significant (EVLW = 0.79 x LTV - 72.8, r = 0.80, p < 0.01). There were significant differences in EVLW/LTV ratio between NYHA class III (0.93 +/- 0.16) and NYHA class I (0.62 +/- 0.22). Thus, it was shown that EVLW was increased in left-sided heart failure and that LTV overestimated the EVLW.

Aged↗

Thallium-201 myocardial SPECT findings at rest in sarcoidosis.

In 41 patients with sarcoidosis (diagnosed according to criteria recommended by the Committee on Diffuse Pulmonary Disease, Ministry of Health and Welfare, Japan 1988), thallium-201 (201Tl) myocardial SPECT was performed to investigate: (1) the ability of 201Tl SPECT to detect cardiac involvement of sarcoidosis with images recorded at rest and 2 hours later, and (2) the relationships between 201Tl myocardial SPECT findings and the activity of sarcoidosis or endomyocardial biopsy findings. As to the abnormal findings in 201Tl myocardial SPECT, (1) a low density area was seen in 13 of 41 cases (31.7%) and non-uniform uptake was found in 17 cases (41.5%), (2) the mean washout ratio (n = 39) was 16.5 +/- 7.4%, which is significantly (p < 0.05) lower than that found in normal subjects, 23.9 +/- 7.5% (n = 10). Of the 19 patients judged visually to be normal, 5 patients had a reduced mean washout ratio less than 12%. Thus, the incidence of abnormal findings including all types of abnormality, on 201Tl myocardial SPECT in sarcoidosis was 63.4% (26/41 cases). In studying the relationship between 201Tl myocardial SPECT findings and the activity of sarcoidosis (as measured by the serum ACE (angiotensin converting enzyme) or lysozyme level, or the presence of more than 30% symphocyte fraction in BALF (broncho-alveolar lavage fluid)), 20 (80%) of 25 cases with 201Tl abnormality were judged to be active sarcoidosis, while only 6 (37.5%) of 16 cases with normal findings on 201TI SPECT were judged to be active.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Blood sampling through a peripheral venous infusion line.

The usefulness of a blood sampling technique for the measurement of blood glucose concentration through a peripheral venous infusion line was investigated with patients under general anesthesia. An infusion line was connected through a T-connector to a venous catheter indwelled in a forearm vein, and lactated Ringer's solution was infused at a flow rate of 100 ml/hour. At an arbitrary time, 0.5 ml of blood sample was obtained through the T-connector after discarding 1.5 ml of blood, while a vein in another arm was punctured to obtain 0.5 ml of blood. As a result, the glucose concentration in the samples from the venous infusion line was strongly correlated with that obtained by direct puncture, and the regression line passed through the origin. This suggests that blood sample from a peripheral venous line can be used in place of samples obtained by direct puncture.

Journal Article↗

Effects of glucose load on brain extracellular lactate concentration in conscious rats using a microdialysis technique.

Changes in the brain lactate concentration in cerebral extracellular fluid (ECF) during intravenous infusion of glucose and local administration of glucose were investigated in adult, conscious, unrestrained rats, with a microdialysis probe in the posterior hippocampus. The rats were infused intravenously with either 25% sucrose solution or 25% glucose solution at a rate of 16.6 microliters.min-1.100 g-1 for three hours. The blood glucose concentration reached 17.0 +/- 2.6 mM at the end of the glucose infusion, and brain ECF glucose showed a parallel change with the blood glucose concentration and increased to 2.37 +/- 0.30 mM. However, blood and brain ECF glucose concentrations did not change in animals infused with the sucrose solution. On the other hand, the blood lactate concentration in the glucose-infused group also increased from 0.93 +/- 0.18 mM to 2.85 +/- 0.39 mM at the end of the glucose infusion, which was significantly higher than that measured in the sucrose-infused group. The blood lactate level in the glucose-infused group returned to the basal level by the end of the experiment. Brain ECF lactate concentrations increased from 1.21 +/- 0.06 mM to 1.69 +/- 0.11 mM in glucose-infused animals, but did not change in the sucrose-infused animals. The brain ECF lactate concentration showed a positive correlation with the brain ECF glucose concentration in glucose-infused animals. Another group of rats was administered glucose locally for 90 min after substitution of artificial cerebrospinal fluid.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Clinical features of neuroleptic malignant syndrome in basal ganglia disease. Spontaneous presentation in a patient with Hallervorden-Spatz disease in the absence of neuroleptic drugs.

Hallervorden-Spatz disease is a rare autosomal recessive disorder in which dopaminergic deficiency in the substantia nigra and its nigrostriatal projection has been identified. It is characterised by a slow but progressive course culminating in death. This case report describes a 13-year-old male, with a clinical diagnosis of Hallervorden-Spatz disease, who developed recurrent episodes of an acute illness, the features of which closely resembled those of the neuroleptic malignant syndrome. However, in this patient there had been no exposure to neuroleptic medication. The clinical events in this case suggest that dopaminergic hypoactivity, which is characteristic of Hallervorden-Spatz disease, can trigger episodes of neuroleptic malignant syndrome.

Acute Disease↗

Microbial glycosidation of some anthracycline antibiotics by an antibiotic-negative mutant of aclarubicin producer.

Microbial conversion of anthracyclinone monosaccharides using aclarubicin-negative mutant of Streptomyces galilaeus was found to produce anthracyclinone disaccharides which had either rhodinose or 2-deoxyfucose as an additional sugar. By this conversion we obtained twelve new anthracyclines from seven anthracyclines which had rhodosamine, N-monomethyldaunosamine or daunosamine at C-7 as a glycosidic sugar. All products had a reduced cytotoxic activity in comparison with those of parent compounds. However, some of them showed a therapeutically improved antitumor effects against L1210 leukemia in vivo.

Aclarubicin↗