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T Fukumoto

Publications and source records attributed to T Fukumoto.

At least 163 records · Page 9Linked to original sources
PubMed1994

Correlation of ultrasound-measured common carotid artery stiffness with pathological findings.

To quantitatively and noninvasively evaluate common carotid atherosclerosis in a series of patients, we measured the stiffness parameter beta, which represents the mechanical properties of the vessel. beta was calculated from the relationship between blood pressure and the diameter of the artery as measured by an ultrasonic, phase-locked, echotracking system. Increases in the severity grade of atherosclerosis as subsequently determined at autopsy were correlated with increased beta values in 60 common carotid arteries (r = .68). Patients with beta values greater than 13 had a pathological diagnosis of atherosclerosis in the common carotid artery. The sensitivity of this discrimination ratio was 80%, and the specificity was 80% as well. Thus, beta shows promise as a useful diagnostic indicator for detecting asymptomatic common carotid atherosclerosis.

Adult↗
PubMed1994

Pathogenesis of late airway changes in long-term surviving lung allografts.

Late airway changes are frequently observed in long-term surviving rat lung allografts. In this present study, we investigate this problem using the mixed lymphocyte reaction, graft-versus-host assay (popliteal lymph node assay), skin grafting from the donor strain to the lung allograft recipient, and histology to evaluate this problem. The results show that spleen cells from recipient rats with long-term surviving lung allografts possessed alloreactivity in mixed lymphocyte reaction against both donor and third-party ACI antigens. Suppressor cell activity was not detected in spleen cells from these recipient rats. The popliteal lymph node assay showed that the response to recipient spleen cells was detectable but weaker than that of naive spleen cells from the same strain. Mean survival time of skin grafts from the donor strain to long-term allograft survivors was significantly longer than that between donor and recipient strains. Chest roentgenograms revealed opacification of long-term surviving lung allografts at 2 to 3 wk after skin transplantation that was coincident with the rejection of the skin grafts, and histologic examination of the lung allografts revealed changes compatible with acute rejection. We conclude that alloreactivity can be demonstrated in rats with long-term surviving lung allografts and suggest that late airway changes in these lungs are immunologically mediated.

Animals↗
PubMed1994

Effects of irradiation, glucocorticoid and FK506 on cell-surface antigen expression by rat thymocytes: a three-colour flow cytofluorometric analysis.

The expression of T-cell antigen receptor (TCR) alpha beta was investigated in rat CD4- CD8- thymocytes during thymic reconstitution after the exposure of animals to irradiation or glucocorticoid. The effect of the immunosuppressant FK506 on the expression of TCR alpha beta in rat CD4- CD8- thymocytes was also examined. The percentage of CD4- CD8- thymocytes constituted 2.6% of total thymocytes and that of CD4- CD8- TCR alpha beta high cells constituted 12.6% of CD4- CD8- thymocytes in normal adult Lewis rats. The percentage of CD4- CD8- TCR alpha beta high cells increased during thymic reconstitution after irradiation, and maximally constituted 28.6% of CD4- CD8- thymocytes on day 7. Similar results were obtained during thymic reconstitution after glucocorticoid treatment. In contrast, continuous treatment with FK506 for 7 days markedly decreased not only the percentages of CD4+ CD8- TCR alpha beta high and CD4- CD8+ TCR alpha beta high thymocytes, but also that of CD4- CD8- TCR alpha beta high thymocytes. These results indicate that rat CD4- CD8- thymocytes contain a subpopulation of mature (TCR alpha beta high) cells. The possible implications of the existence of this subpopulation with regard to thymocyte differentiation and maturation are discussed.

Animals↗
PubMed1994

Effects of FK506 on surface antigen expression by regenerating thymocytes after sublethal irradiation in the rat.

To determine the effects of FK506 on the intrathymic maturation of T cells, we analyzed changes in surface antigen expression by regenerating thymocytes after sublethal irradiation. Two-color flow cytofluorometric analysis of the regenerating thymocytes revealed that FK506 had few effects on the maturation of rat thymocytes from CD4-8- to CD4+8+, and from TCR alpha beta- MHC class I- to TCR alpha beta low MHC class I+ (TCR alpha beta, alpha and beta chains of the T cell antigen receptor). However, defects in the maturation of CD4+8+ cells to CD4+8- cells and of TCR alpha beta low MHC class I+ cells to TCR alpha beta high MHC class I+ cells were observed after FK506 administration. Furthermore, three-color analysis also detected a maturational defect of CD4-8+ TCR alpha beta high cells. Immunohistochemical analysis using MoAbs specific for MHC and TCR alpha beta revealed marked atrophy of the thymus medulla, suggesting disturbances in thymocyte regeneration and maturation. These results suggest that the maturation of CD4-8- TCR alpha beta- MHC class I- cells to CD4+8+ TCR alpha beta low MHC class I+ cells may be FK506 resistant, whereas FK506 may interfere with the maturation of CD4+8+ TCR alpha beta low MHC class I+ thymocytes not only to CD4+8- TCR alpha beta high MHC class I+ cells but also to CD4-8+ TCR alpha beta high MHC class I+ cells. We also demonstrated the possibility of enrichment of CD4-8- cells after sublethal irradiation and the existence of small subpopulations of CD4+8- TCR alpha beta- and CD4-8+ TCR alpha beta- cells which might mature to CD4+8+ cells in rat thymus.

Animals↗
PubMed1994

The effects of FK506 and dexamethasone on rat thymocyte differentiation.

We investigated the effects of FK506 and glucocorticoids (GC) on rat thymocytes using flow cytofluorometry. Rats were treated with GC (0.1 mg/body, by single injection), with FK506 (1 mg/kg/day, for 7 days), or with FK506 and GC. GC alone significantly decreased the percentage of CD4+8+ thymocytes and increased the percentages of CD4-8-, CD4+8- and CD4-8+ thymocytes on day 7. FK decreased the percentage of CD4+8- and CD4-8+ thymocytes and increased the percentage of CD4+8+ thymocytes on days 5 to 14. FK and GC induced a significant decrease in the number of CD4+8+ thymocytes greater than that seen with GC alone on day 7. The absolute number of TCR alpha beta high MHC class Ihigh thymocytes after FK and GC was significantly lower than that of the control group, and was slightly lower than that after FK alone on day 14. These results suggest that combined treatment with FK506 and GC acts complexly to decrease rat CD4+8+ thymocytes and prevents thymocyte differentiation and maturation.

Animals↗
PubMed1994

[Antibacterial activities of new quinolones against fresh clinical isolates].

In order to investigate antibacterial activities of new quinolones (NQs) against a number of clinical isolates obtained in our laboratory during a period from February, 1993 to January, 1994, minimum inhibitory concentrations (MICs) were determined using most of the NQs available in the market as of December, 1993. The obtained results are summarized as follows: 1. Noticeable differences were observed among the antibacterial activities of 8 different NQs tested against Gram-positive bacteria, i.e., there were large differences in their MIC distributions. Some differences were also observed among different NQs in ratios of NQ-resistant strains among Staphylococcus spp. From these results, it seems necessary to further study tolerance mechanisms of these Gram-positive bacteria toward different NQs and also to examine possible differences in antibacterial activities among different NQs against Gram-positive bacteria in clinical settings. 2. MIC distributions against Gram-negative bacteria were also different among the 8 NQs tested. Though elevated MICs were observed against NQ-resistant Gram-negative bacteria in many cases, and somewhat higher, though not exceedingly high, MIC values than those against NQ-sensitive bacteria were found in other cases, patterns of MIC values against different NQ-resistant Gram-negative bacteria were similar for all of the 8 NQs tested. This may explain the fact that most of NQ-resistant Gram-negative bacteria showed similar resistant patterns to the 8 NQs tested. 3. Among the NQ-resistant bacteria, were found Haemophilus influenzae and Neisseria gonorrhoeae strains. Ratios of resistant strains were approximately 10% or lower for the former and approximately 20% for the latter. 4. With MICs of ampicillin and cefaclor used as control, it appears that benzylpenicillin (PCG)-insensitive or PCG-resistant Streptococcus pneumoniae (PISP or PRSP) and CEPs-resistant Escherichia coli are increasing.

4-Quinolones↗
PubMed1994

[Antibacterial activities of cefetamet against clinically isolated strains from community acquired respiratory tract infections (II)].

Antibacterial activities of cefetamet (CEMT) against clinically isolated strains from patients with community acquired respiratory tract infections were compared to those of other oral beta-lactam antibiotics in the period from January to March 1994. The following results were obtained. 1. CEMT showed strong antibacterial activities against three major pathogens causing community acquired respiratory tract infections, Streptococcus pyogenes, Streptococcus pneumoniae, and Haemophilus influenzae. However, antibacterial activities of CEMT against benzylpenicillin (PCG)-insensitive S. pneumoniae (PISP) and PCG-resistant S. pneumoniae (PRSP) were slightly weaker than of those of some the reference antibiotics. 2. No MIC value changes of CEMT were observed from year to year against Moraxella subgenus Branhamella catarrhalis and Klebsiella pneumoniae.

Bacteria↗
PubMed1994

[A case of hepatic atrophy by irradiation].

A 44-year-old woman was treated with 60Co irradiation (total dose, 6000 rads) focused on the right side porta hepatis under the diagnosis of cholangiocarcinoma in 1975. Seventeen years after the treatment, she was admitted to our institution because of dull pain at right hypochondriac region. Abdominal CT demonstrated an extreme hepatic atrophy and tumor mass in the right lobe of the liver. In November, 1991 right tri-segmentectomy was performed under the diagnosis of hepatocellular carcinoma. Laparotomy revealed the extreme atrophy of the right lobe and associated hypertrophy of the left lobe of the liver. In this case radiation hepatitis occurred after irradiation to the liver and it was followed by the extreme hepatic atrophy as a long term effect of high dose irradiation on the liver.

Adult↗
PubMed1994

[Antimicrobial activities of ciprofloxacin against recently obtained clinical isolates].

In order to evaluate antimicrobial activity of ciprofloxacin (CPFX), minimum inhibitory concentrations (MICs) of CPFX and other drugs were determined against clinical isolates that were obtained in our laboratory from January to December of 1991, and of 1993. The results are summarized as follows: 1. CPFX-resistant strains were on the increase in various strains, compared to those in the early 1980s. However, many of CPFX-resistant strains were multi-drug resistant including beta-lactams. In addition, they showed cross resistance to other fluoroquinolone agents. 2. MIC distribution of other drugs suggested that there were increased frequencies of benzylpenicillin (PCG)-insensitive Streptococcus pneumoniae (PISP) and CEPs-resistant Escherichia coli. However, MIC distribution of CPFX to these resistant strains were in a relatively low range. 3. When isolates of 1991 were compared to those of 1993, we confirmed that CPFX-resistant strains decreased among certain bacteria such as Staphylococcus aureus. Also we confirmed that fewer CPFX-resistant strains were found among bacteria that may be highly related to infections encountered in daily medical care.

Bacteria↗
PubMed1994

[Antimicrobial activities of fosfomycin against Streptococcus pneumoniae and Haemophilus influenzae recently observed in sinusitis patient].

In order to examine antimicrobial activities of fosfomycin (FOM), the minimum inhibitory concentrations (MICs) of FOM and those of control drugs were determined against Streptococcus pneumoniae and Haemophilus influenzae isolated from sinusitis patients from September to November, 1993, and the following results were obtained. 1. Among 50 S. pneumoniae strains tested, there were 10 strains (20.0%) of benzylpenicillin (PCG)-insensitive S. pneumoniae (PISP) and 2 strains (4.0%) of PCG-resistant S. pneumoniae (PRSP); but the MIC distributions of FOM among the PISPs and the PRSPs were almost identical to those among the PCG-susceptible S. pneumoniae (PSSP). 2. There were 12 strains (24.0%) of beta-lactamase producing strains among 50 strains of H. influenzae tested, but the FOM's MIC distribution among these strains was almost identical to that among beta-lactamase non-producing strains. 3. The results obtained on the MIC90s of FOM against S. pneumoniae and H. influenzae suggest that the nebulization treatment with FOM nasal preparation satisfies the condition "above the MIC".

Drug Resistance, Microbial↗
PubMed1994

[Correlation between respiratory or circulatory state and postoperative extravascular lung water volume in patients undergoing surgery for esophageal carcinoma of the thorax].

Postoperative extravascular lung water index (EVLWI, ml/kg) was analyzed in 30 patients who underwent esophagectomy through right thoracotomy for esophageal carcinoma from the day of operation to 5th postoperative day, in order to clear the correlation between respiro-circulatory state and EVLWI. The results are as follows. 1. EVLWI on 1st postoperative day correlated significantly not only with blood loss during operation (p < 0.01, r = 0.65) but also with systemic vascular resistance index on 1st postoperative day (p < 0.05, r = -0.43). 2. EVLWI correlated with the respiratory index (RI) on the 2nd and 4th postoperative day (p < 0.01), suggesting that EVLWI is an important indicator in judging the respiratory state following esophagectomy. 3. EVLWI on 4th postoperative day correlated with accumulative fluid balance up to 4th postoperative day (p < 0.05, r = 0.41), however neither correlated with other hydrostatic parameters nor the COP-PCP gradient. Furthermore, EVLWI on 4th postoperative day correlated more significantly with oxygen consumption index (p < 0.05, r = 0.58) than that with accumulative fluid balance up to 4th postoperative day. According to those results, the increased systemic vascular permeability immediately after the surgery attributes to the increase of EVLWI on the 1st postoperative day. Whereas, the increased EVLWI on 4th postoperative day depends on not only the hydrostatical factors but also the increased pulmonary vascular permeability caused by the surgical maneuver to the lung during esophageal surgery.

Esophageal Neoplasms↗
PubMed1994

[Antibiotic activities of cefpirome against fresh clinical isolates resistant to multiple drugs].

Using multiple drug-resistant clinical isolates isolated since September 1992, minimum inhibitory concentrations (MICs) of cefpirome (CPR) were determined. Several control drugs were also used, and these MIC-determinations were made to determine the antibiotic activity of CPR. The obtained results are summarized as follows: 1. Antibiotic activities of CPR against methicillin-resistant Staphylococcus spp., Enterococcus faecalis, and benzylpenicillin-insensitive or resistant Streptococcus pneumoniae showed that expanded antibacterial spectrum of CPR and its enhanced antibiotic action against Gram-positive bacteria. We suggest that among the existing fourth-generation cephem antibiotics, CPR is "characteristically strong against Gram-positive bacteria". 2. Strong antibiotic activities of CPR were recognized against bacteria of family Enterobacteriaceae that were resistant to the third-generation cephems. The strong antibiotic activities appeared to be due to CPR's stability and decreased affinity for beta-lactamase. 3. Antibacterial spectrum of CPR was expanded against non-glucose fermented Gram-negative bacilli including Pseudomonas aeruginosa. It appears that this expansion of antibacterial spectrum is due to CPR's affinities for a wide range of penicillin-binding proteins as well as its improved permeability into tissues.

Cephalosporins↗
PubMed1994

[beta-lactamase activity in sputum of patients with community-acquired lower respiratory tract infections].

beta-Lactamase production and activities in sputa of patients with community-acquired lower respiratory tract infections (LRTI) were determined and following results were obtained: 1) Suspected causative organisms frequently isolated were H. influenzae and Streptococcus pneumoniae. Similar results were previously reported. 2) Various beta-lactamase producing indigenous bacteria were detected. In many cases these indigenous beta-lactamase producing strains were isolated even when suspected causative bacteria were not beta-lactamase producers. 3) beta-Lactamase activities were detected from 61.5% of the sputa tested. Remaining activities of antibiotics added to the sputa were highly correlated with detection of beta-lactamases produced by suspectedly causative and indigenous strains and with presence of beta-lactamase activities in the sputa. Sulbactam/cefoperazone was stable in sputa than other antibiotics tested. 4) We concluded that the beta-lactamase produced by indigenous strains can be one of the factors of indirect pathogenicity in the community-acquired LRTI.

Cefoperazone↗
PubMed1994

[Antimicrobial activities of cefuroxime against recent clinical isolates].

Antimicrobial activity of cefuroxime axetil (CXM-AX) was compared with those of other cephem antibiotics against clinically isolated strains obtained mainly from outpatients of our center in a period from January to September of 1990 and 1993. Minimum inhibitory concentrations were determined and the following results were obtained. 1. The results suggested that, compared with reports of studies conducted with clinical isolates in early 1980's, MIC80 of CXM were equal to or lower against Staphylococcus spp., Streptococcus pyogenes, Escherichia coli, Klebsiella spp., Proteus mirabilis, Haemophilus influenzae, Moraxella subgenus Branhamella catarrhalis, Neisseria gonorrhoeae, Peptostreptococcus spp., and Propionibacterium acnes, except for Streptococcus pneumoniae, MIC80 which was slightly higher. 2. MIC90 of comparator drugs reflected those of new resistant organisms recently appeared, such as benzylpenicillin (PCG)-insensitive S. pneumoniae (PISP), cephem-resistant E. coli and Klebsiella spp., new quinolone-resistant H. influenzae and N. gonorrhoeae. Methicillin-resistant Staphylococcus aureus (MRSA) was detected also from specimens of community acquired infections. From the nature of MRSA detected in those situations MRSA appeared to present a continuing problem. 3. MIC90 against strains obtained from patients with community acquired infections was a good index of increases of multidrug-resistant organisms in the past. Therefore, the determination of MIC90 is important in examining changes with time of sensitivities or resistances of clinically isolated strains to antimicrobial drugs. 4. Antimicrobial activities of CXM against recent clinical isolates showed the existence of problems as mentioned above. However, MIC of CXM as well as those of comparator drugs indicated that antimicrobial activities of CXM against Staphylococcus spp., Streptococcus spp., H. influenzae appeared to be relatively strong, and it is concluded that cefuroxime axetil still is one of the clinically useful oral antimicrobial drugs in the 1990's.

Bacteria↗
PubMed1993

Immunohistochemical analysis of rat liver using a monoclonal antibody (HAM8) against gap junction.

Four monoclonal antibodies were raised against crude gap junction fractions of rat liver to clarify the distribution of gap junctions during animal development and to analyze gap junction expression in vivo and the polarity of hepatocytes in vitro. Among the monoclonal antibodies obtained, HAM8 antibody recognized the 27-kDa rat liver gap junction protein connexin 32. This antibody recognized gap junctions at the contiguous faces of hepatocytes, and the antigen was also observed in exocrine pancreas and salivary gland but not in kidney, heart, esophagus, or thymus. HAM8 did not react with amphibian or fish liver, heart, esophagus, stomach, or intestine as assessed via the immunofluorescence method on frozen sections. A few hepatocytes and many hemopoietic cells were seen in rat fetal liver at 15 days of gestation. HAM8 antigen was expressed on some hepatocytes but not on any hemopoietic cells. As the fetus grew, the number of hepatocytes in the liver increased gradually, together with the amount of HAM8 antigen. The distribution of HAM8 antigen at 25 days after birth was similar to that in adult liver. When the expression of HAM8 antigen was examined in primary cultured hepatocytes using the immunofluorescence method, the antigen was observed clearly between the hepatocytes. However, most of the HAM8 antigen on the free surface of hepatocytes disappeared within 4 hr. HAM8 antigen was not expressed on AH-7974 rat hepatoma cells when they formed small islets in the rat peritoneal cavity or within the liver. When HAM8 IgG antibody was injected intravenously, the HAM8 signal was expressed in the liver.

Animals↗
PubMed1993

Effect on liver and splanchnic circulation of graded flow rates through portal-systemic bypass during acute portal occlusion.

Using graded flow rates through a passive portal-systemic bypass during 2-hr portal occlusion in dogs, splanchnic, hemodynamic, and metabolic changes and liver insults were evaluated to determine critical bypass flow. To exclude effects caused by reduced circulating blood volume, constant preocclusion levels of cardiac output were maintained throughout the study by increasing intravenous infusion rates. With the decrease in bypass flow rates during portal occlusion, portal pressure increased, superior mesenteric arterial flow decreased, and hepatic arterial flow rapidly increased and these parameters maintained their individual levels during occlusion. These hemodynamic parameters recovered to nearly normal levels 3 hr after release of the portal clamp. Metabolic acidosis progressed with decreasing bypass flow, but portal potassium and inorganic phosphorus levels showed a significant rise only when there was no bypass. Portal levels of creatine phosphokinase BB, beta-glucuronidase, and endotoxin did not show significant changes corresponding to bypass flow. The amounts of infusion required were 3 to 6 times the basal level (10 ml/kg/hr) during occlusion and 1.7 to 3 times after release in 30% or less bypass groups. Upon ceasing infusion 3 hr after release, dogs in the 10% or less bypass groups underwent circulatory insufficiency. Changes in total adenine nucleotide and energy charge ratio of the liver, postoperative changes in transaminase levels, and animal survival indicated that a 2-hr interruption of the portal flow, either sufficiently or insufficiently bypassed, caused only minimal insults of the liver.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗