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K Mashita

Publications and source records attributed to K Mashita.

At least 19 recordsLinked to original sources
PubMed1995

[Bacteriological and clinical evaluation tazobactam/piperacillin in infectious diseases in surgical field].

We carried out bacteriological and clinical studies on tazobactam/piperacillin (TAZ/PIPC), a combination drug of piperacillin with the new beta-lactamase inhibitor tazobactam, in various infectious diseases in surgical field such as intra-abdominal infections (peritonitis and intra-abdominal abscess), hepatobiliary infections (cholecystitis, cholangitis and hepatic abscess) and secondary infections in wound, etc. The total number of cases treated with the combination drug was 164. Of these cases, 141 cases were assessable for clinical responses including 60 cases with intra-abdominal infections, 38 cases with hepatobiliary infections, and 43 cases with secondary infections. Clinical efficacy rates of the drug were 83.3% in cases with intra-abdominal infections, 86.8% in cases with hepatobiliary infections, and 95.3% in those with secondary infections, hence the overall efficacy rate was 87.9%. In the cases from which beta-lactamase producing strains were isolated, clinical efficacy rates were 84.8% in cases with intra-abdominal infections, 84.6% in those with hepatobiliary infections, and 96.2% in those with secondary infections, hence the overall efficacy rate was 88.9%. Bacteriological efficacy rates were 92.9% in cases with Gram-positive bacterial infections, 64.3% in those with Gram-negative bacterial infections, and 100% in those with anaerobic bacterial infections. Bacteriological efficacy rates were 84.2% in cases with single bacterial infections and 56.5% in those with multi-bacterial infections, and the overall bacteriological efficacy rate was 69.0%. In the cases of infections with beta-lactamase producing strains, bacteriological efficacy rates were 80.0% in cases with Gram-positive bacterial infections, 75.0% in those with Gram-negative bacterial infections, and 100% in those with anaerobic bacterial infections. They were 82.6% in cases with single bacterial infections and 57.9% in those with multi-bacterial infections; the overall bacteriological efficacy rate was 67.2%. The bacterial eradication rate was 79.9% against all the isolates, and it was 79.2% against beta-lactamase producing isolates. In addition, we compared the sensitivity distribution of the isolates to TAZ/PIPC with those to control drugs piperacillin (PIPC), cefotiam (CTM), ceftazidime (CAZ), sulbactam/cefoperazone (SBT/CPZ). The MIC50 and MIC90 values of TAZ/PIPC against all strains were 3.13 micrograms/ml and 50 micrograms/ml, respectively. MIC50 values show that TAZ/PIPC was two times less effective than CAZ and SBT/CPZ but four times more effective than CTM; furthermore, from the MIC90 values, TAZ/PIPC was four times more effective than PIPC, CTM and CAZ. The MIC50 and MIC90 values of TAZ/PIPC against beta-lactamase producing strains were 3.13 micrograms/ml and 50 micrograms/ml, respectively.(ABSTRACT TRUNCATED AT 400 WORDS)

Abdominal Abscess↗
PubMed1994

[Bacteria isolated from intraabdominal infection and their susceptibilities to antimicrobial agents].

Bacteria isolated from intraabdominal infections during the period from July 1982 to June 1993 were investigated with regard to their classifications according to a joint research by 9 university hospitals in Japan. The following results were obtained. 1. A total of 971 strains were isolated from 684 out of 597 patients with peritonitis, and 287 strains out of 971 were isolated from postoperative peritonitis. 2. The most predominant organism isolated from patients with acute peritonitis was Escherichia coli (28%), followed by Bacteroides fragilis group (17%), Gram-positive anaerobic cocci (16%), Enterococcus spp. (9%) and Klebsiella spp. (8%). 3. Against E. coli, cefmenoxime, cefuzonam, cefozopran, aztreonam and carumonam showed MIC50 less than 0.05 micrograms/ml. Against B. fragilis group, erthromycin, clindamycin, imipenem, lincomycin and latamoxef showed MIC50 less than 0.78 micrograms/ml. 4. The most predominant organism isolated from patients with postoperative peritonitis was Enterococcus spp. (20%) and followed by Pseudomonas spp. (14%), and Staphylococcus spp. (13%), E. coli (9%), Enterobacter spp. (8%) and Klebsiella spp. (8%). We suggest that cefazolin, cefmetazole, flomoxef, cefmenoxime, cefuzonam, and latamoxef are the first choice agents in empiric therapy for the treatment of acute peritonitis.

Aged↗
PubMed1993

The inhibitory effect of noradrenaline on thyrotrophin-stimulated 3,5,3'-tri-iodothyronine and thyroxine release is mediated through a Ca(2+)-dependent process in the thyroid gland of the mouse.

We examined the effect of noradrenaline on the release of 3,5,3'-tri-iodothyronine (T3) and thyroxine (T4) from perifused mouse thyroid. Noradrenaline suppressed the thyrotrophin (TSH)-stimulated release of T3 and T4. The addition of prazosin, which is a specific alpha 1 antagonist, or the depletion of Ca2+ from the perifusion buffer completely abolished the inhibitory effect of noradrenaline on TSH-stimulated T3 and T4 release. Noradrenaline did not inhibit TSH-stimulated cyclic adenosine 3',5'-monophosphate (cAMP) release in the presence of 3-isobutyl-1-methylxanthine (IBMX), which inhibits both cAMP-specific and calmodulin-sensitive phosphodiesterases. Noradrenaline significantly suppressed the TSH-stimulated release of T3 and T4 in the presence of IBMX. These results suggest that the inhibitory effect of noradrenaline on TSH-stimulated T3 and T4 release is not mediated through a cAMP-dependent process or the activation of a calmodulin-sensitive phosphodiesterase, and that this inhibition is mediated through a Ca(2+)-dependent process regulated by the alpha 1-adrenergic system in the mouse thyroid.

1-Methyl-3-isobutylxanthine↗
PubMed1992

The operative risk factors of cholelithiasis in the elderly.

A total 725 patients with cholelithiasis were divided into three groups according to age, and the risk factors and morbidity rates compared. Group 1 consisted of those aged younger than 49 years, group 2 of those aged between 50 to 69 years, and group 3 of those aged over 70 years. In group 3, the incidence of calculi in the common bile duct was significantly higher than in the other two groups (p less than 0.05), and therefore, choledochotomy accompanying cholecystectomy was performed more often in this group (p less than 0.01). The rate of complications related to calculi and the presence of underlying disease were also higher in this group than in the two younger groups (p less than 0.05), as were preoperative abnormal liver or renal function tests, anemia and hypoproteinemia (p less than 0.05). The rate of positive bile cultures in group 3 was 75.6 per cent which was again significantly higher than in groups 1 and 2 (p less than 0.01). Postoperative complications appeared in 14.3 per cent of the group 3 patients, which was not statistically higher than in group 2 (9.7 per cent), but the percentages of both groups 2 and 3 were high compared to the 4.3 per cent of group 1 (p less than 0.01). The rates of complications directly attributable to the surgical procedures were 2.0 per cent in group 1, 4.8 per cent in group 2, and 5.1 per cent in group 3 with no significant differences between the three groups. There was no increase in the technical problems associated with the surgical procedures performed on the elderly patients and thus, if the operative risks are precisely evaluated and treated cautiously elderly patients should tolerate surgery for cholelithiasis well.

Aged↗
PubMed1992

[Postoperative infection control in patients with hepatic, biliary tract, and pancreatic cancers].

Postoperative infection occurs more frequently in patients with malignant disease than in patients with benign disease. Postoperative infection control in patients with hepatic cancer, biliary tract cancer and pancreatic cancer is studied. Although in patients with jaundice due to malignancy the rate of positive bacterial culture of the bile collected at the time of PTCD was low, the rate of positive bile culture increased after 10 to 14 days of PTCD. The predominant strain was Enterococcus spp., followed by Klebsiella spp., Enterobacter spp. and E. coli in that order. These bacteria isolated from the bile were considered to be causative organisms of postoperative infection. Prophylactic antibiotics after the operation for jaundice due to malignancy should be chosen based on the results of bile culture. In patients undergoing hepatectomy, which is considered to be an aseptic operation, gram positive cocci such as S. aureus was the most frequently encountered organism. On the other hand, in patients undergoing hepatectomy and intestinal anastomosis, enteric bacteria were frequently isolated from the infectious foci. In this study there were 6 cases of methicillin-resistant S. aureus (MRSA) postoperative infection, 3 cases after pancreatoduodenectomy, and 3 cases after hepatectomy. Even after an aseptic operation, postoperative MRSA infection is likely to occur in patients undergoing a more invasive operation, so hospital infection control should be again emphasized.

Bacteria↗
PubMed1992

[Penetration of levofloxacin in bile].

The penetration into bile of a new pyridonecarboxylic acid derivative, levofloxacin (LVFX), was studied in a closs-over method with ofloxacin (OFLX) as the control drug in 6 post-operative patients. The lengths of time to the maximum concentrations in bile and the total areas under the curves were both almost the same for these 2 compounds, although the maximum bile concentration of LVFX was slightly lower than that of OFLX. A stability test for LVFX in human bile revealed that over 95.4% of the initial amount was recovered up to 24 hours after commencement of incubation at a room temperature, thus the stability in bile was similar to that in water. The penetration of LVFX which possesses twice as strong antibacterial activities as OFLX was similar to that of OFLX, suggesting that LVFX is useful against bile duct infections.

Aged↗
PubMed1992

[Identification and antibiotic prophylaxis of high-risk patients in biliary tract surgery].

A prospective randomized trial has compared 3 policies of antibiotic prophylaxis in biliary surgery. Patients considered to be high-risked against postoperative infection were randomly allocated to 2 groups: in group CTM-H, patients were given cefotiam; in group CMX-H, patients were given cefmenoxime. Patients free of risk factors (group CTM-L) were all given cefotiam. The high-risk factors adopted in this trial were; emergency surgery, presence of jaundice or cirrhosis, malignant disease, diabetes mellitus, age over 70, recent biliary tract infection, choledocholithiasis, and previous biliary surgery. Postoperative infection occurred in 2.1% (4/190) in the CTM-L group, which was lower compared to 15.5% (11/71) of the CMT-H group (p less than 0.01), and 11.3% (8/71) of the CTM-H group (p less than 0.01). The rates of bacterial isolation from intraoperative bile culture and wound swab were significantly high in the two high-risk groups compared to the low-risk group, but is was not different within the two high-risk groups. These findings suggest that while cefotiam is appropriate for prophylaxis for the low-risk patients, the utmost care should be taken in the high-risk patients to prevent intraoperative contamination along with prophylactic antibiotic therapy which covers the bacteria isolated from the bile.

Adolescent↗
PubMed1991

A bacteriological study of perforated duodenal ulcers.

Peritoneal fluid sampling and bacteriological examination were performed in 63 patients with perforated duodenal ulcers, and the results compared with those in 175 patients with other perforations. Bacterial culture was positive in 100 per cent of the patients whose perforations occurred in the colon, whereas it was positive in only 44.4 per cent of those with duodenal perforations, being negative in many cases when the interval from perforation to surgery was short. A mixed contamination with both aerobes and anaerobes was usually found in the cases of lower digestive tract perforation, and the isolates from duodenal perforations were uniquely aerobes in most cases. It is suggested that bacteria play a minor role in the pathogenesis of early stage duodenal perforation, which supports the technique of primary closure without indwelling drainage tubes during early stage operations following sufficient peritoneal lavage. Moreover, if the stomach is empty at the time of perforation and the peritonitis is localized, even conservative therapy seems possible, provided it is begun shortly after the perforation.

Adolescent↗
PubMed1991

The relationship between juxtapapillary duodenal diverticula and the presence of bacteria in the bile.

A total of 432 patients with gallstone disease were studied with respect to the existence of juxtapapillary duodenal diverticula and their relationship to the presence of bacteria in the bile. A total of 63 patients were found to have diverticula with an incidence of 14.6 per cent, being significantly higher in the elderly group aged 60 years or older (p less than 0.01), and no sex difference was noted. Among the patients with diverticula, positive bacterial cultures of bile were recognized at a significantly higher frequency, being found in 49 of the 63 patients (77.8 per cent; p less than 0.01), and the probability of bilirubinate stones was also higher, being found in 35 of 37 patients (94.6 per cent; p less than 0.01). The presence of a diverticulum bore significant relation to a higher positive bile bacterial culture (p less than 0.05), dilation of the common bile duct (p less than 0.05), and elevation of the bile duct pressure (p less than 0.05), even when the conditions were divided into cholecystolithiasis or choledocholithiasis. It was suggested that the presence of a diverticulum affected the flow in the bile duct by narrowing it from the outside and chronically stimulating the papilla, inducing biliary tract infection and/or the formation of gallstones. As the surgical procedures for juxtapapillary duodenal diverticula, including its indications, have not been established, long term follow up investigations seem necessary.

Adult↗
PubMed1991

Alpha 1-adrenergic regulation of thyrotropin-stimulated release of 3, 5, 3' -triiodothyronine and thyroxine from perifused mouse thyroid.

The effect of methoxamine, a specific alpha 1-adrenergic agonist, on the release of T3, T4 and cAMP from perifused mouse thyroid was studied to clarify the role of the alpha 1-adrenergic receptor in the regulation of thyroid hormone secretion. TSH-stimulated T3 and T4 release was inhibited significantly by methoxamine. With regard to cAMP release, methoxamine inhibited TSH-stimulated cAMP release in the presence of 4-(3-butoxy-4-methoxybenzyl)-2-imidazolidinone but did not inhibit TSH-stimulated cAMP release in the presence of 3-isobutyl-1-methylxanthine. Methoxamine did significantly suppress TSH-stimulated release of T3 and T4 in the presence of each phosphodiesterase inhibitor. Depletion of Ca2+ in the perifusion buffer abolished completely the inhibitory effect of methoxamine on TSH-stimulated T3 and T4 release. The present study suggests that activation of the alpha 1-adrenergic receptor inhibits TSH-stimulated T3 and T4 secretion through a Ca(2+)-dependent mechanism in the mouse thyroid gland.

1-Methyl-3-isobutylxanthine↗
PubMed1991

Inhibitory effects of ionophore A23187 on the release of thyroid hormone and colloid reabsorption in mouse thyroid glands.

The effect of the ionophore A23187 on a. the release of thyroid hormone from perifused mouse thyroid glands and b. the morphological changes in follicular epithelial cells was evaluated. A23187 at a concentration of 5 mumol/l significantly inhibited both the TSH- and the forskolin-stimulated release of T3 and T4. In the presence of 3-isobutyl-1-methylxanthine or (4-(3-butoxy-4-methoxybenzyl)-2-imidazolidinone) RO 20-1724, A23187 did not affect the forskolin-stimulated release of cAMP, but did inhibit the release of T3 and T4 stimulated by forskolin. Light and electron microscopic evaluation of the follicular epithelial cells of mouse thyroid tissues following 1-h stimulation with forskolin showed numerous pseudopods engulfing luminal colloid of various size and the presence of reabsorbed colloid droplets in the apical cytoplasm. Quantitative electron microscopic analysis revealed that the addition of the ionophore A23187 reduced the number of reabsorbed colloid droplets to one eighth in follicular epithelial cells. These observations suggest that the increase in intracellular Ca2+ induced by the ionophore A23187 inhibits the TSH-stimulated thyroid hormone release independently of the cAMP level, and that the suppression of thyroid hormone release may be due to an inhibition of colloid reabsorption.

1-Methyl-3-isobutylxanthine↗
PubMed1991

Human recombinant interleukin 1 inhibits TSH-stimulated morphological changes in thyroid follicles cultured as semi-organs.

To study the effects of human recombinant interleukin-1 on thyrocytes, we cultured thyroid follicles as semi-organs, each consisting of approximately 10-20 follicles, in the presence or absence of IL-1 alpha or beta. Semi-organ culture reproduces the in vivo environment well. After culture for 2 or 4 days, the follicles were incubated with TSH (10 U/l) for 4 h and fixed for light and electron microscopical examinations. Regardless of the presence or absence of IL-1, follicular structure, polarity, and luminal colloid did not change during culture. In thyroid epithelial cells cultured without IL-1, TSH markedly induced elongation of microvilli and formation of reabsorbed colloid droplets. On the other hand, both IL-1 alpha and beta inhibited these TSH-stimulated changes. The degree of inhibition correlated with the concentration of exposure to IL-1. We conclude that IL-1 inhibits TSH-stimulated morphological changes in thyroid follicles cultured as semi-organs, depending on the concentration of IL-1.

Animals↗
PubMed1991

[Clinical study on fleroxacin in surgical infections].

We conducted clinical studies on fleroxacin (FLRX), a new pyridone carboxylic acid derivative, for the treatment of periproctal abscess, secondary infections (due to wounds, burns or surgical operations), mastitis or areolitis and others with once daily dose of 200 mg or 300 mg. We obtained the following results. Clinical efficacy was evaluated in total 27 cases including periproctal abscess 11, secondary infection 8, mastitis or areolitis 6, phlegmon 1 and infected atheroma 1. Clinical efficacies were rated as excellent in 14, good in 9, fair in 4 cases. The overall efficacy rate was 85.2%. Bacteriological studies identified 14 strains of aerobic Gram-positive organisms, 12 of aerobic Gram-negative organisms and 6 of anaerobic organisms. The overall bacteriological efficacies were: eradicated in 26 strains, unchanged 2 and unidentified 4, hence the eradication rate was 92.9%. As for side effects, anorexia and nausea were observed in one of the 27 cases. In clinical laboratory tests, slight elevations of GPT and BUN were observed in 1 case each. We consider FLRX to be a useful antimicrobial agent at once daily dose for surgical infections.

Abscess↗
PubMed1990

Interferon-gamma reduces actin filaments and inhibits thyroid-stimulating hormone-induced formation of microvilli and pseudopods in mouse monolayer thyrocytes.

To study the role of interferon-gamma (IFN gamma), which is released from activated lymphocytes in the development of lymphocytic thyroiditis, we investigated the effects of IFN gamma on the morphology of mouse thyrocytes, using scanning electron microscopy. Thyrocytes were cultured in monolayers for 5-7 days and incubated with TSH (10 mU/ml) for 1 h before fixation. IFN gamma (200 U/ml) was added to the culture medium for 1 h to 5 days before TSH stimulation. Coculture of thyrocytes with IFN gamma for more than 24 h inhibited TSH-induced morphological changes in the thyrocytes; IFN gamma inhibited the increase in the number of and elongation of microvilli and the appearance of pseudopods. IFN gamma also reduced the number of actin filaments in thyrocytes, as confirmed by immunofluorescence photometry. These results suggest that IFN gamma inhibits the morphological response of thyrocytes to TSH stimulation by the reduction of actin filaments.

Actins↗
PubMed1989

Postoperative infection prophylaxis for upper gastrointestinal tract surgery--a prospective and comparative randomized study of cefoxitin and ceftizoxime.

A prospective and randomized clinical study was conducted in order to compare cefoxitin (CFX) and ceftizoxime (CZX) as prophylactic antibiotics. Two hundred and three consecutive cases of elective upper gastrointestinal tract surgery, performed at our institute between January, 1983, and March, 1986, were entered in the trial. The patients were assigned randomly, before surgery, to the CFX or to the CZX group. Two grams of the assigned antibiotic was first administered during surgery and then continued at a dose of 1 gram, every 8 hrs for a total of 4 days. One patient was withdrawn from the study due to an allergic reaction. Both groups were comparable in sex, age, underlying disease, diagnosis, operation, and preoperative laboratory data. There were 18 infections related to the operation in the CFX group, while there were only 3 in the CZX group (p less than 0.001). The number of unrelated infections in each group was 6 and 6 respectively (NS). No special differences were found between the two groups regarding the kinds of microorganisms isolated, and no significant differences were seen in the adverse effects of either antibiotic. Our study demonstrated that ceftizoxime was more efficient than cefoxitin in preventing postoperative infection, following upper gastrointestinal tract surgery.

Adult↗
PubMed1989

[Postoperative enterocolitis and current status of MRSA enterocolitis--the result of a questionnaire survey in Japan].

There is a trend of increase in the number of Staphylococcus aureus infection recently, and postoperative enterocolitis due to methicillin resistant strains is appearing. Because of this, a nation wide questionnaire survey on postoperative enterocolitis was conducted to clarify the status since 1980. Of the 875 major surgical institutes to which we sent the questionnaire, 370 (42.3%) replied and 67 case reports were obtained from 25 institutes. Twenty published reports were added to this and a total of 87 cases were evaluable. The number of postoperative enterocolitis increased after the year 1985, and those resulting from MRSA infection were more frequent in the northern half of Japan including the Kanto area. It was more frequent in males and the mean age was 57.9. Their onset was sudden, beginning with diarrhea and/or fever between the second and fifth postoperative days. In most of the cases, the cephalosporin group of antibiotics, especially of the third generation, were administered preceding the enterocolitis. Six of cases (24%) did not survive, and in some of the institutes they were considered to be hospital infections, as they appeared consecutively between a short period of time.

Adult↗
PubMed1989

Inhibitory effect of lithium on the release of thyroid hormones from thyrotropin-stimulated mouse thyroids in a perifusion system.

We studied the effect of lithium on the release of T3, T4, and cAMP from perifused mouse thyroids and on cAMP content in thyroid pieces. Lithium significantly inhibited T3 and T4 release from TSH-stimulated mouse thyroids. This inhibitory effect on thyroid hormone release was dependent on the concentration of lithium. Under continuous stimulation with TSH and 3-isobutyl-1-methylxanthine, both cAMP release and cAMP content were significantly decreased by lithium. In addition, we studied the effect of lithium on (Bu)2cAMP-stimulated thyroid hormone release. T3 and T4 release was stimulated by (Bu)2cAMP in a similar way to TSH. Lithium significantly inhibited (Bu)2 cAMP-stimulated T3 and T4 release from perifused mouse thyroids. These results suggest that lithium inhibits the action of TSH in the thyroid gland by both suppression of cAMP production and inhibition at a step beyond cAMP generation.

1-Methyl-3-isobutylxanthine↗