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Biomedical subjects

H Tamura

Publications and source records attributed to H Tamura.

At least 271 records · Page 15Linked to original sources
PubMed1993

A case of hematophagic histiocytosis associated with acute renal failure.

The present report describes a rare case of hematophagic histiocytosis associated with acute renal failure. A 32-year-old woman was referred to us from a local hospital because of progressive deterioration of renal function, jaundice and a bleeding tendency. The physical findings at admission revealed hyperemic conjunctivae, gingival bleeding, hepatomegaly, and generalized myalgia. Laboratory data indicated a decrease in platelet count, azotemia and hyperbilirubinemia. Marked elevation of serum triglycerides and ferritin was also noted. Histiocyte proliferation with phagocytosis of erythrocytes and platelets was observed in a bone marrow aspirate. A renal biopsy specimen exhibited lesions generally observed in acute tubular necrosis: degeneration and necrosis of tubular epithelial cells; round cell infiltration and edema in the interstitium; and unremarkable glomeruli. The serum titer to coxsackievirus B1 rose from < 4x at admission to 16x after recovery from the illness, suggesting that this virus may have been the causal organism of the accompanying infection. The patient's symptoms improved rapidly with supportive therapy, and complete restoration of renal function was achieved in 20 days. The morphological characteristics of the bone marrow aspirate and the clinical course were compatible with hematophagic histiocytosis.

Acute Kidney Injury↗
PubMed1993

[Comparative study in graft patency of individual and sequential grafting as coronary bypass].

We analyzed the graft patency rates of the individual saphenous vein graft (SVG) group and those of the sequential SVG group. In the individual SVG group, 184 SVGs were anastomosed to 184 coronary arteries. Twenty-six SVGs were used sequentially to 52 coronary arteries in the sequential group. The patency rates of all the SVGs in both groups showed no significant differences. The patency of left anterior descending (LAD), left circumflex (LCX), right coronary artery (RCA) and diagonal branch (Dx) was 96%, 67%, 90% and 63% respectively in the individual SVG group. In the sequential SVG group, the patency rates of LCX (95%) were much higher than those (67%) of the individual SVG group (p < 0.05). The patency rates of side-to-side anastomoses (SSAs) were 92% and those of the distal end-to-side anastomoses (ESAs) were 96% in the sequential SVG group. There were no significant differences between SSAs and ESAs. While, the patency rates of SSAs-Dx, ESAs-Dx, SSAs-LCX and ESAs-LCX were 89%, 100%, 100%, and 93% respectively in the sequential SVG group. There were no significant differences between two groups. These results showed that the sequential grafting is useful and effective for LCX coronary arteries in coronary artery bypass surgery. In conclusion, it seems that in LCX coronary arteries, the patency rates obtained by the sequential SVG technique are better than those obtained by using the individual SVG technique.

Coronary Artery Bypass↗
PubMed1993

[Clinical preeminence of single aortic cross-clamping for proximal anastomoses in coronary artery bypass surgery].

We evaluated the preeminence of the construction of proximal anastomoses during single aortic cross-clamping periods in coronary artery bypass surgery. Twenty-six patients were divided into two groups; single aortic cross-clamping (SAX) group: 13 patients, partial aortic clamping (PAC) group: 13 patients. In this study, these two groups were compared in terms of aortic cross-clamping time (AXT), total extracorporeal circulation (ECC) time (TECCT), ECC weaning time (WT), amount of cardioplegic solution, total levels of serum CPK and CPK-MB, and graft patency. The results were analyzed by ANOVA and chi-square test. AXT was longer in the SAX group compared with the PAC group (78.2 +/- 5 versus 63.2 +/- 4 min; p < 0.05). TECCT (120.4 +/- 6 versus 109 +/- 5 min) and WT (37.4 +/- 2 versus 41 +/- 2 min) were not significant between the two groups. The total amount of cardioplegic solution was greater in the SAX group compared with the PAC group (1100 +/- 60 versus 927 +/- 43 ml; p < 0.05). The levels of serum CPK and CPK-MB were a little lower in the SAX group, but there were no significant differences between the SAX group and the PCA group. The graft patency of both two groups were excellent. From these results, SAX is not critical in the routine of coronary artery bypass surgery. Clinically, the SAX technique allows us to select more suitable areas of the ascending aorta for placement of all the proximal grafts if the ascending aorta is short.(ABSTRACT TRUNCATED AT 250 WORDS)

Anastomosis, Surgical↗
PubMed1993

[Application of the concept of fuzzy logistic controller for treatment of hypertension during anesthesia].

The concept of Zadeh's fuzzy logistic controller was applied to control hypertension during anesthesia, and its clinical usefulness was examined in patients undergoing elective surgery. Arterial blood pressure was determined by use of an automatic blood pressure device. Nicardipine was used as hypotensive drug. Based on the fuzzy control rules, we developed state-action diagram so as to maintain systolic blood pressure at around 130 mmHg. Nicardipine was infused by using a digitally controlled infusion pump, and its infusion rate was changed according to this diagram. Although acute hypertension associated with endotracheal intubation was not significantly attenuated, hypertension associated with either skin incision or endotracheal extubation, where blood pressure increased slowly, was successfully controlled with our system. These results suggest that the application of the concept of fuzzy logistic controller is useful for treatment of hypertension during anesthesia, especially when blood pressure increases slowly.

Anesthesia↗
PubMed1993

[Surgical treatment of cardiac cachexia with mitral valve disease: the effect of preoperative IVH and left atrial plication on postoperative respiratory condition].

Twenty-four patients with cardiac cachexia associated with mitral valve disease were evaluated from the point of postoperative respiratory management. Our previous study suggested that preoperative intravenous hyperalimentation (IVH) had just a effect on postoperative respiratory management, but another study suggested that left atrial plication (LAP) for giant left atrium might improve the postoperative respiratory function. Therefore, four groups could be identified: (1) IVH group (17 patients), (2) No-IVH group (7 patients), (3) LAP group (6 patients), (4) No-LAP group (18 patients). The hospital mortality was 18% in IVH group and was not related to the postoperative respiratory distress. On the contrary, the mortality in No-IVH group was 57%, related to the postoperative respiratory distress. The mortality of LAP group was 67%, and was related to the respiratory distress except one patient. In No-LAP group which had undertaken preoperative IVH, the mortality was 17%. As a result, preoperative IVH therapy may consider to be a favorite procedure in order to get the good postoperative respiratory condition, but LAP itself would be suspicious for this purpose.

Adult↗
PubMed1993

[Prosthetic valve endocarditis after double valve replacement].

This is a report of a patient who underwent re-AVR due to prosthetic valve endocarditis after double valve replacement (MVR, AVR). A 54-year-old female was admitted to other hospital on April 14, 1990, because of high fever, progressive anemia, and cardiomegaly. The patient was hospitalized to our department urgently with the diagnosis of prosthetic valve endocarditis. Arterial blood culture grew methicillin-resistant Staphylococcus epidermidis. Echocardiography showed a vegetation at the disc of the mechanical valve in the mitral position, but we could not find any vegetation or thrombus there at the reoperation, and the aortic mechanical valve seemed to be intact. Signs of inflammation continued to be positive after reoperation. On the 33rd hospital day, a diastolic murmur was heard, and emergency cardiac catheterization was done. Detachment of the prosthetic aortic valve and rupture of the sinus of Valsalva due to mycotic aneurysm, and the dissection of the aorta had occurred. We performed re-AVR and replacement of the ascending aorta. The patient died of multiple organ failure following drug-induced hepatic failure. It is suggestive that we missed the prosthetic aortic valve endocarditis during the reoperation. Our thoughts and introspections on the echocardiographic diagnosis of the prosthetic valve endocarditis after double valve replacement were discussed.

Aneurysm, Infected↗
PubMed1992

A new sensitive microplate assay of plasma endotoxin.

We have developed a microplate method for determining endotoxin in platelet-rich plasma-using Endospecy, an endotoxin-specific chromogenic Limulus test reagent. Nonspecific activators and inhibitors of the test were eliminated by exposing samples (5 microliters) to the alkali reagent consisting of KOH, CaCl2, Triton X-100, ethyleniminepolymer and N,N-bis(2-hydroxyethyl)glycine. The recoveries of various endotoxins were almost complete and not enhanced by dilution. The dose-response curve was linear over endotoxin concentrations of 2-400 pg/ml with good precision (C.V. less than 5.0%). Normal human plasmas (n = 30) contained less than 5.0 pg/ml of endotoxin in reference to that of Escherichia coli 0111: B4. All plasma samples with high concentration of endotoxin by a conventional method showed high values by the microplate assay as well. Since it does not require centrifugation, the new treatment allows the whole reactions to proceed on the same microplate. This permits us to apply the Limulus test to an automated assay system, making plasma endotoxin determination simpler and more rapid than a conventional test tube method.

Detergents↗
PubMed1992

G test, a new direct method for diagnosis of Candida infection: comparison with assays for beta-glucan and mannan antigen in a rabbit model of systemic candidiasis.

An indirect method to measure beta-glucan, a major structural component of yeast cell walls, is available, but has the disadvantage of requiring the combined use of two assays. Recent reports describe the fungal index, which measures the difference between the conventional limulus test, in which factors C and G react with endotoxin and beta-glucan, and a new endotoxin-specific test, in which only factor C reacts with endotoxin. The G test was developed as a direct method to measure beta-glucan, and contains only factor G reacting with beta-glucan alone. In this study, the G test was examined in sera of rabbits with experimental systemic candidiasis, and compared with the fungal index and mannan assay. The G test showed positive in all rabbits with systemic candidiasis faster and with higher titers than with the fungal index. Three rabbits with fulminant systemic candidiasis showed higher levels of reactivity with the G test and the fungal index than two rabbits with mild reactions. Mannan was positive by at least one serum in four of five rabbits by the latex agglutination test, and there was a good correlation between these assays. The G test is a good serodiagnostic method for the detection of candidiasis.

Animals↗
PubMed1992

Determination of plasma (1-->3)-beta-D-glucan: a new diagnostic aid to deep mycosis.

We present additional evidence that plasma from patients with deep-seated mycoses contains (1-->3)-beta-D-glucan. Digestion of such samples with endo-(1-->3)-beta-D-glucanase completely abolished the ability of the plasma to activate factor-G, a horseshoe crab coagulation enzyme that is extremely sensitive to this polysaccharide. Measurement of plasma (1-->3)-beta-D-glucan is a promising method for the diagnosis of deep-seated mycoses and for monitoring the response of these infections to antifungal therapy.

Amino Acid Sequence↗
PubMed1992

Molecular cloning of a rat liver cDNA encoding the 16 kDa subunit of vacuolar H(+)-ATPases: organellar and tissue distribution of 16 kDa proteolipids.

A cDNA (T3-L) encoding the 16 kDa subunit of vacuolar H(+)-ATPase was cloned from a cDNA library of rat liver. A polypeptide of 155 amino acids with a molecular mass of 15,807 Da (pI = 9.5) having four hydrophobic stretches was predicted. T3-L polypeptide was 92% and 100% identical with the 16 kDa proteolipid of bovine chromaffin granule and that of mouse, respectively. Antisera raised against the NH2-terminal of the T3-L polypeptide reacted positively with the membrane ghosts of rat liver tritosomes and the partially purified H(+)-ATPase thereof. Western blotting of subcellular fractions with the antisera showed high abundance of 16 kDa protein in the lysosomes, although a significant amount was also detected in the Golgi apparatus. Western blotting of rat tissues revealed high levels of 16 kDa proteolipid in the brain and the kidney. Northern blots with T3-L similarly showed considerably high expression of T3-L mRNA in the brain and the kidney. Southern hybridization of rat genomic DNA with T3-L showed at most three distinct bands, regardless of the stringency of hybridization and whether hybridization was performed with its subfragments. This suggests the possibility of multiple (at least three) homologous/identical genes encoding 16 kDa proteolipid. The possible presence and significance of isoforms of 16 kDa proteolipid in rats are discussed.

Amino Acid Sequence↗
PubMed1992

Mass production of sphingomyelinase of Bacillus cereus by a protein-hyperproducing strain, Bacillus brevis 47, and its purification.

Sphingomyelinase (sphingomyelin cholinephosphohydrolase) [EC 3.1.4.12] of Bacillus cereus was overproduced in a protein-hyperproducing strain, B. brevis 47, by cloning the gene into an expression vector pNU211, which has been developed to express a foreign gene utilizing a promoter and a signal sequence of an outer cell wall protein gene. From 1 liter of culture, about 10 mg of protein was purified to near-homogeneity by two steps of column chromatography; this is almost 500 times higher production compared to the conventional preparation from the original strain, B. cereus IAM 1208. The N-terminal amino acid sequence of the secreted enzyme was identical to that of the authentic enzyme, indicating that the signal sequence for secretion of B. cereus was processed properly in B. brevis 47.

Amino Acid Sequence↗
PubMed1992

Molecular analysis of immunoglobulin heavy chain genes coding for idiotypic and anti-idiotypic antibodies involved in B-B cellular interaction.

We recently reported that a unique B cell clone (B19-1d), specific for a cross-reactive idiotype (CRI) on MOPC104E myeloma protein (M104E), enhances Igh-restricted CRI+ antibody production. In this paper, we report the nucleotide sequences of immunoglobulin heavy chain variable regions (VH) of both M104E and B19-1d-derived hybridoma (HB19) antibodies. The sequence data revealed that both belong to the J558 germ line VH gene subfamily. Strikingly, not only the VH region, but also the leader sequences of M104E and HB19 are very similar to each other at 88% (VH) and 91% (leader) homology, but they use different D and J segments. The VH region sequence similarity is highest among the germ line VH gene sequences of the BALB/c J558 subfamily so far screened. Southern hybridization data, using 5'-noncoding regions of either M104E or HB19 genomic VH gene clones as probes, revealed that both VH genes are conserved in the M104E CRI producer strains of mice. Moreover, these probes show the restriction length polymorphism pattern of mouse VH genes in various strains. That the HB19 VH gene locates to the 5' upper arm of the M104E VH gene on the chromosome was suggested by Southern blot hybridization. Immunoglobulin VH gene restriction of idiotypic and antiidiotypic B-B cellular interaction is discussed from a molecular point of view.

Amino Acid Sequence↗
PubMed1992

T-independent polyclonal activation of B cells in vitro by immunoglobulin binding substance (IBS) from the granary weevil.

Experiments are described for T-independent polyclonal activation of B cells in vitro by the immunoglobulin binding substance (IBS) from the granary weevil. The affinity-chromatographically purified IBS was used. IBS is a heat-, alkali- and acid-stable glucopeptide which is characterized by non-specific immunoglobulin binding to the Fab fragment. The purified IBS consists of three polymer homologues whose molecular weights are 12-14,000, 25-30,000 and more than 150,000 Da. IBS did not stimulate DNA synthesis by murine T cells, macrophages or plasma cells whereas it did stimulate that by mature B cells without any help from T cells or macrophages. IBS also stimulated both in vitro IgG production by spleen cells and in vitro sensitization of spleen cells by sheep red cells (SRBC). IBS was found to stimulate DNA synthesis by B cells mediated by binding to surface immunoglobulins of B cells. IBS is thought to be a useful amplifier for inducing human hybridomas and a valuable tool for examining mature B cells, both diagnostically and experimentally.

Animals↗
PubMed1992

Activity-dependent potentiation and depression of visual cortical responses to optic nerve stimulation in kittens.

1. To see whether long-lasting changes in synaptic efficacy are induced in the developing visual cortex (VC), field potentials evoked by test stimulation given alternatively to each of the optic nerves (ONs) were recorded from VC of kittens ranging in age from 4 to 8 wk. In some experiments, field potentials were recorded simultaneously from the dorsal lateral geniculate nucleus (LGN) in addition to VC. 2. Tetanic stimulation was applied to one of the ONs for 1-60 min at 5 Hz. Homosynaptic potentiation of cortical responses, defined as an increase lasting > 2.5 h in the cortical field potential evoked by test stimulation of the ON that was tetanized, was induced without any changes in LGN responses in 3 of the 12 kittens tested. Heterosynaptic depression, defined as a decrease lasting > 0.5 h in the field potential evoked by stimulation of the ON that was not tetanized, was also induced in two of those three kittens. 3. To elucidate a role of inputs originating from spontaneous activity of retinal ganglion cells in induction of potentiation and depression in the cortex, tetrodotoxin (TTX) was injected into both eyes of 11 kittens. After we confirmed the suppression of retinal activity by TTX, tetanic stimulation was applied to ON. Homosynaptic potentiation of cortical responses was induced in 6 of the 11 kittens, and the ratio of the mean amplitude of posttetanic responses to that of pretetanic responses for the 11 kittens was on average larger than that for the 12 control kittens. Heterosynaptic depression was not observed in any of the 11 kittens. 4. To see a role of postsynaptic activity in induction of potentiation and depression, gamma-aminobutyric acid (GABA) was applied continuously to the VC by an infusion pump in 10 kittens. Tetanic stimulation was given to ON while cortical activities were suppressed by GABA. After recovery of cortical activities, homosynaptic depression was found to be induced in 3 of the 10 kittens, but homosynaptic potentiation was not observed at all. The ratio of amplitude of posttetanic to pretetanic responses at the tetanized side for the 10 kittens was on average smaller than that for the 11 TTX-injected kittens. 5. These results can be accounted for by the modified covariance model in which the relation of postsynaptic activity and direction of changes in synaptic efficacy is formulated.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1992

Digoxin-like immunoreactive substance in urine of patients with mucocutaneous lymph node syndrome (MCLS).

Levels of digoxin-like immunoreactive substance (DLIS) and dehydroepiandrosterone sulfate (DHEA) in urine from patients with mucocutaneous lymph node syndrome (MCLS) were measured by radioimmunoassay. Because DLIS of stored samples was often below the level of detection by conventional immunoassay, the authors used 80% ammonium sulfate and extraction with phosphate buffer and then 80% hot ethanol. To study the origin of raised levels of DLIS in urine, the synthesis of DLIS by cultured human umbilical vein endothelial cells (HUVEC) was tested in vitro. The correlation between DLIS and DHEA levels was not significant. Mean levels of urinary DLIS corrected for creatinine in the patients with MCLS were significantly higher than in both normal and diseased controls. The culture medium of HUVEC was found to contain DLIS activity. These results show that MCLS should be added to the clinical states associated with an increased urinary concentration of DLIS and that the endothelial cells are one source of DLIS in man.

Blood Proteins↗
PubMed1992

Enhancing effect of butorphanol on medetomidine-induced sedation in pigs.

Enhancing effect of an opiate agonist-antagonist butorphanol (0.2 mg/kg) on sedation induced by medetomidine (80 micrograms/kg) was evaluated in pigs. Butorphanol significantly enhanced the depth of medetomidine-induced sedation and prolonged the duration of that assessed by posture score and spontaneous movement of pigs. The combination of medetomidine and butorphanol produced excellent muscle relaxation and moderate surface analgesia which was enough for procedures with mild pain in pigs.

Animals↗