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Biomedical subjects

T Matsuda

Publications and source records attributed to T Matsuda.

At least 1,351 records · Page 75Linked to original sources
PubMed1987

The in vitro response of osteoblasts to bioactive glass.

Osteoblasts from neonate rat calvaria migrated in culture from the endocranial surface of parietal bones onto fragments of bone-bonding 45S5 glass or non-bone-bonding quartz glass. These organ culture units were maintained for up to 4 wk. No significant production of extracellular matrix (ECM) was seen on the quartz glass samples. However, osteoblasts colonized the 45S5 samples in multilayers and produced abundant ECM as seen by light (LM), scanning electron (SEM) and transmission electron (TEM) microscopy. The interface developed on 45S5 glass was designated as either Type I (non-collagen-bonding) or Type II (showing direct interdigitation of collagen with the calcium phosphate-rich glass surface). It was concluded that, since this in vitro method is capable of reproducing some aspects of the known in vivo behaviour of 45S5, such techniques may be developed as a means of batch-testing bioactive biomaterials and investigating bone cell/biomaterial interactions.

Animals↗
PubMed1987

Antibody response to haptenic sugar antigen: immunodominancy of protein-bound lactose formed by amino-carbonyl reaction.

Several reducing sugars with structural analogy (glucose, galactose, lactose, melibiose, maltose and cellobiose) were bound to a carrier protein ovalbumin by amino-carbonyl reaction, and the non-enzymatically glycosylated proteins were injected into mice (BALB/c, C57BL/6, DBA/2 and C3H/He strains) with Freund's adjuvant. Antibody responses to the haptenic sugar antigens were analyzed quantitatively by enzyme-linked immunosorbent-assay using each sugar-bovine serum albumin complex. The haptenic sugar antigen from lactose induced a markedly higher response of specific antibody as compared with the haptenic sugar antigens from the other sugars. The antibody raised against the lactose adduct reacted well with lactulose (4-o-beta-D-galactopyranosyl-D-fructose) or alpha-N-acetyl-epsilon-N-deoxylactulosyl-L-lysine. The results suggested that immunogenicity of haptenic sugar antigens was remarkably different in sugar chemical structure, and that the lactose adduct formed by lactose-protein amino-carbonyl reaction could be an immunodominant antigenic determinant.

Amino Acids↗
PubMed1987

Mast cells in the ovarian bursa of the golden hamster.

In the golden hamster, the number and maturity of mast cells were determined in serial sections of the ovarian bursa stained with either toluidine blue and acid fuchsin or alcian blue and safranin. The number of mast cells in connective tissue within 250 microns of the bursal mesothelium significantly decreased on Day 4 compared to the numbers between Days 1, 2, and 3 of the estrous cycle. The number of mast cells in connective tissue within 50 microns of the bursal mesothelium significantly decreased from Day 1 to 2 of the cycle, but did not vary between Days 2 and 4 of the cycle. Mast cells in this zone accounted for approximately 40-50% of the mast cells located within 250 microns of the bursal mesothelium throughout the cycle. If the tissue volume is taken into consideration, mast cells occurred in concentrations several times higher in connective tissue close to the bursal mesothelium than in connective tissue more distant from the mesothelium. Mast cells were occasionally located in the layer of bursal mesothelium, and some of them appeared to discharge granules into the bursal cavity. All mast cells encountered in the hamster bursa were mature cells, which stained reddish-orange with safranin. These results suggest that mast cells in the golden hamster ovarian bursa may act on the submesothelial connective tissue, bursal cavity, or ovary. The possible biological significance of their proximity to the bursal mesothelium is discussed.

Animals↗
PubMed1987

Early coverage of deep hand burns with groin flaps.

Deep burns of the hands require skin flap coverage in order to protect the exposed vital structures. The groin flap is a safe and effective method of obtaining early closure of these defects. We have used groin flaps to cover deep hand burn defects in nine patients. In each case, groin flaps effectively covered the various defects, such as the volar aspect of the wrist, dorsum of the hand, first web space, thumb, and fingers.

Adult↗
PubMed1987

The effect of burn wound size on resting energy expenditure.

Numerous formulas have been used to estimate the calorie requirements of hypermetabolic burned patients. With the recent development of instrumentation for indirect calorimetric measurements, questions have been raised concerning the validity and accuracy of the early equations. Because metabolic rate decreases during the course of wound healing, we attempted to determine the magnitude of hypermetabolism and the accuracy of the Curreri formula in patients with various wound sizes. Twenty-eight patients with a mean initial burn size of 29% body surface area (BSA) had measurements of resting energy expenditure (REE) at regular intervals during their postburn course. Concomitantly, basal energy expenditure (BEE) was calculated from the Harris-Benedict equation; and the predicted energy needs were calculated using the Curreri formula adjusted for current wound size (ACEE). Three significantly different burn size (%BSA) groups were identified: Group 1, 1-10%; Group 2, 11-30%; and Group 3, 31-60% BSA. The measured REE was 27, 35, and 50% greater than the BEE in Groups 1, 2, and 3, respectively (p less than 0.001). The ACEE underestimated REE by 7% in Group 1, and overestimated REE by 13 and 35% in Groups 2 and 3, respectively (p less than 0.001). Resting energy expenditure should be measured at regular intervals in individuals with open burn wounds greater than 10% BSA in order to adjust nutritional support appropriately.

Adult↗
PubMed1987

Effects of a new antibiotic, isohematinic acid, on the resistance of mice to experimental infections.

Isohematinic acid, an antibiotic newly isolated from the culture broth of Actinoplanes philippinensis SANK 61681, was assessed for its ability to enhance nonspecific resistance to bacterial infections against Escherichia coli and Pseudomonas aeruginosa in mice. This agent, as well as BM 12,531 (Azimexon), was found to prolong the survival of normal mice infected with E. coli and also of compromised mice infected with either E. coli or P. aeruginosa, whose defense system had been deteriorated by treatment with carboquone, an alkylating agent. Like BM 12,531, isohematinic acid administered to normal mice significantly increased the nitroblue tetrazolium reducing potency of polymorphonuclear leucocytes (PMN), indicating that the microbicidal activity of PMN was enhanced by these agents. In addition, in the compromised mice these agents were able to restore the number of peripheral blood leucocytes, which had been reduced to about 30% of the normal level by carboquone. These results suggest that isohematinic acid, like BM 12,531, enhances nonspecific resistance to these bacterial infections by stimulating the microbicidal activity of PMN and inducing leucocytosis.

Adjuvants, Immunologic↗
PubMed1987

Measurement of aortic blood flow with MR imaging: comparative study with Doppler US.

An innovative magnetic resonance imaging technique was applied to the measurement of blood flow in the abdominal aorta. The technique combines selective excitation and visualization from an orthogonal view. The distance that fluid has moved is directly visualized. The blood flow velocity at every 50 msec throughout the cardiac cycle was measured in a short time (about 4 minutes) using electrocardiographic gating and repeated excitations in each cycle. Measurements were compared with those obtained by Doppler ultrasound (US) as a reference. The pulsatile change of flow velocity in the cycle correlated well with the Doppler US recording. Two flow velocity indexes, peak flow velocity and the velocity integral, also showed good correlation (r = .98 for both). This method is applicable for clinical use and is useful for measurement of high flow rates, as found in arteries.

Adult↗
PubMed1987

Inhibition of hypertension and salt intake by oral taurine treatment in hypertensive rats.

Effects of oral treatment with taurine on fluid intakes produced by renin were assessed in spontaneously hypertensive rats of the Okamoto strain (SHR). Renin injected into the preoptic area increased water intake and evoked salt (2.7% NaCl solution) intake, and angiotensin II injected into this area increased water intake, but not salt intake, in both SHR and control normotensive Wistar-Kyoto rats (WKY). The salt intake elicited by renin, but not water intake produced by renin or angiotensin II, was potentiated in SHR. These effects of renin and angiotensin II on fluid intakes were antagonized by previous administration of taurine or gamma-aminobutyric acid into the cerebral ventricles in both strains. When SHR received water containing 3% taurine from 32 to 105 days of age, development of hypertension was inhibited. Renin administered into the preoptic area at 105 days of age caused an increase in salt intake, but the increase was markedly inhibited by the oral administration of taurine as well. These results show that salt appetite produced by centrally administered renin is exaggerated in SHR and that development of hypertension as well as renin-induced salt appetite in SHR is inhibited by dietary taurine.

Administration, Oral↗
PubMed1987

Antidiuretic effects of morphine microinjected into the hypothalamic supraoptic and paraventricular nuclei in a water-loaded and ethanol-anesthetized rat.

Effects of morphine microinjected into the hypothalamic supraoptic (SON) and paraventricular (PVN) nuclei, which contain neurons producing and releasing antidiuretic hormone (vasopressin), on the outflow and the osmotic pressure of urine and other visceral functions were investigated in a rat which was loaded with water and anesthetized with ethanol. The opioid drug, having predominantly mu-agonist activity, when microinjected into the SON or PVN induced potent antidiuretic effects in dose-dependent and time-dependent manners with no significant effects on the other visceral functions. The approx. ED50 values for morphine were 19 and 9 nmol when it was microinjected into the SON and PVN, respectively. The antidiuretic effects showed slow onset and long duration, with a minimal outflow at approx. 50 min after microinjection and a return to approx. 50% of the initial control value by 1.5 hr. The morphine-induced effects were inhibited by pretreatment with naloxone or atropine, but not inhibited by pretreatment with alpha- or beta-adrenoceptor antagonists, suggesting that the antidiuretic effects were mediated through an opioid receptor having low sensitivity to naloxone and also possibly mediated through a muscarinic receptor which was stimulated probably by the ACh released by morphine.

Anesthesia↗
PubMed1987

Successful delivery in a female with thrombotic thrombocytopenic purpura.

A 28-year-old female, who suffered from thrombotic thrombocytopenic purpura (TTP) in the 14th week of her first pregnancy, recovered after a plasma exchange followed by an induced abortion. From six months after the abortion, she no longer required plasma infusions every 3-4 weeks to prevent a relapse of TTP manifested as thrombocytopenia, and complete remission continued until her next pregnancy. In her second pregnancy, she had an immediate relapse of TTP and responded to plasma infusion until the 24th week. However, the TTP gradually became resistant to plasma infusion, and developed into toxemia with edema, hypertension and proteinuria in the 27th week. Although the TTP was alleviated by the infusion of large amounts of plasma, the placenta failed as the result of numerous white infarcts. She delivered a 948 g live baby by cesarean section in the 33rd week. The baby had transient thrombocytopenia but did not suffer from TTP. The mother required plasma infusions every 3-4 weeks for about five months, and she has continued in remission.

Adult↗
PubMed1987

[Clinical studies with a new non-ionic contrast medium (iopamidol) in intravenous pyelography in aged patients].

Iopamidol (IOPAMIRON 300) was examined for excretory urography on 21 patients, between 70 and 94 years old, with reference to visualization, safety and urinary excretion. The results about visualization and safety were compared with those obtained with 60% Urografin. Iopamidol was demonstrated visualization nearly equivalent to that with Urografin, and 19% better pyelogram. Especially, calix showed a clearer contrast than those obtained with Urografin. None of the 21 old patients experienced any side effects or adverse reactions. No abnormalities were noted in serum chemistries. Iopamidol was not quickly excreted into the urine, only 19% during the first 2 hours, in elder patients.

Aged↗
PubMed1987

Effects of Bay k 8644 and nifedipine on isolated dog cerebral, coronary and mesenteric arteries.

Vasoconstrictor effects of Bay k 8644, a dihydropyridine Ca++ agonist, and vasorelaxant effects of nifedipine were investigated in helical strips of dog cerebral (basilar, posterior cerebral and middle cerebral) and peripheral (coronary and mesenteric) arteries. The addition of Bay k 8644 produced a dose-dependent contraction in the absence of any contractile agent in the basilar artery with a pD2 value of 8.53. Similar sensitivity to Bay k 8644 was observed in the posterior cerebral, middle cerebral or coronary artery. Bay k 8644 was much less effective in producing a contraction in the mesenteric artery. An elevation of the concentration of extracellular K+ eliminated the difference between the responses to Bay k 8644 in the basilar and mesenteric artery. Contractile responses of the basilar artery to Bay k 8644 were antagonized competitively by nifedipine (pA2 = 8.17), but non-competitively by diltiazem. The pA2 values for nifedipine antagonism of Bay k 8644 responses with the elevated K+ were the same between the basilar and mesenteric arteries. Increased sensitivity to exogenously added K+ also was observed in cerebral and coronary arteries when compared with the mesenteric artery. The addition of nifedipine to an unstimulated strip produced a dose-dependent relaxation in cerebral and coronary arteries, but not in the mesenteric artery. When the cerebral and peripheral arteries were contracted with K+ to the same magnitude, nifedipine produced similar relaxations among these arteries. Nifedipine was less efficacious in antagonizing the contractile response to Bay k 8644 compared with the contractile response to K+ in cerebral arteries. These results suggest that 1) the voltage-dependent Ca++ channels in the cerebral and coronary arteries are in different states of activation from those in the mesenteric artery, 2) Bay k 8644 contracts the cerebral and coronary arteries by acting primarily on the same site, presumably dihydropyridine receptors of the voltage-dependent Ca++ channels at which nifedipine acts, 3) the dihydropyridine receptors were the same between the basilar and mesenteric arteries and 4) there may be a difference in the state of the Ca++ channel in the arteries between the stimulation with Bay k 8644 and K+-depolarization.

3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethy↗