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Keizo Yamaguchi

Publications and source records attributed to Keizo Yamaguchi.

At least 55 records · Page 3Linked to original sources
PubMed2005

Sepsis caused by food-borne infection with Escherichia coli.

We report a case of sepsis caused by Escherichia coli (E. coli) of serotype O-143. A 78-year-old man developed symptoms of gastroenteritis after ingesting raw meat on noodles. He rapidly developed respiratory failure. Blood culture grew E. coli. The sepsis seemed to have directly spread from a food-borne infection. The development of primary sepsis after ingesting E. coli is very rare. We suspect that bacterial translocation played a major role. Serotype O-143 is recognized in enteroinvasive E. coli (EIEC) as well as in Shigella dysenteriae. The pathogen in the present case is suspected of being EIEC although the isolated E. coli strain was negative for the inv and ipa genes.

Aged↗
PubMed2005

[In vitro susceptibilites to levofloxacin and various antibacterial agents of 11,475 clinical isolates obtained from 52 centers in 2002].

The susceptibilities of bacteria to fluoroquinolones (FQs), especially levofloxacin, and other antimicrobial agents were investigated using 11,475 clinical isolates collected in Japan during 2002. Methicillin susceptible staphylococci, Streptococcus pyogenes, Streptococcus pneumoniae, Moraxella catarrhalis, the family of Enterobactericeae, Haemophilus influenzae and Acinetobacter spp. exhibited stable and high susceptibilities to FQs. The rate of FQs-resistant MRSA was 80 approximately 90%, being markedly higher than that of FQs-resistant MSSA. The FQs-resistance rate of MRCNS was also higher than that of MSCNS, however, it was lower than that of MRSA. No FQs-resistant clinical isolates of Salmonella spp. were detected in any of the surveys. Thirteen of Escherichai coli 696 isolates, 8 of Klebsiella pneumoniae 630 isolates and 33 of Proteus mirabilis 373 isolates produced extended-spectrum beta-lactamase (ESBL), furthermore 6 of 13 in E. coli, 1 of 8 in K. pneumoniae and 14 of 31 ESBL-producing isolates, and in P. mirabilis were FQs resistant. Attention should be focused in the future on the emergence of ESBL in relation to FQs resistance. The rate of FQs-resistant P. aeruginosa isolated from urinary tract infection (UTI) was 40 approximately 60%, while 15 approximately 25% of isolates from respiratory tract infection (RTI) were resistant. IMP-1 type metallo beta-lactamase producing organisms were found in 49 of P. aeruginosa 1,095 isolates, 7 of S. marcescens 586 isolates and 4 of Acinetobacter spp. 474 isolates, respectively. Glycopeptide-resistant enterococci or S. aureus was not found.

Anti-Bacterial Agents↗
PubMed2005

[Evaluation of Dipstick 'Eiken' Legionella for detection of Legionella pneumophila serogroup 1 urinary antigen using the immunochromatographical method].

Dipstick 'Eiken' Legionella is a reagent for detection of Legionella pneumophila serogroup 1 antigen in urine using the immunochromatographical method. The reagent was evaluated using the reference and clinical isolated strains and clinical specimens. BinaxNOW Legionella and Legionella antigen [Mitsubishi] were evaluated simultaneously. Using four of L. pneumophila serogroup 1 strains, the minimal detectable concentration of Dipstick 'Eiken' Legionella was 5.0 x 10(4) to 2.0 x 10(5) colony forming unit/ml, it was approximate four times high in comparison with other two kits. And no positive reaction was obtained from 45 of non-L. pneumophila serogroup 1 strains. When Dipstick 'Eiken' Legionella was compared with BinaxNOW Legionella among 50 urine samples obtained from patients with pneumonia and 50 urine from healthy adults, the sensitivity was 94.7%, the specificity was 100.0% and the agreement was 99.0%. Dipstick 'Eiken' Legionella is found to be useful diagnostic reagent for Legionella infection in clinical laboratories.

Antigens, Bacterial↗
PubMed2005

[Comparative studies on activities of antimicrobial agents against causative organisms isolated from patients with urinary tract infections (2003). I. Susceptibility distribution].

The bacterial strains isolated from 565 patients diagnosed as having urinary tract infections (UTIs) in 14 institutions in Japan were collected between August 2003 and July 2004. The susceptibilities of them to many kinds of antimicrobial agents were investigated. Of them, 701 strains were estimated as prophlogistic bacteria and used for the investigation. The strains consisted of 258 Gram-positive bacterial strains (36.8%) and 443 Gram-negative bacterial strains (63.2%). Against Staphylococcus aureus, vancomycin (VCM) showed the strongest activity and prevented the growth of all strains with 2 microg/mL. Against Streptococcus agalactiae, ampicillin (ABPC), cefozopran (CZOP), imipenem (IPM), and clarithromycin (CAM) showed a strong activity and the MIC90 was 0.125 microg/mL or less. Against Enterococcus faecalis, VCM, ABPC, and IPM showed a strong antibacterial activity. The antibacterial activity of cephems to Escherichia coli was generally good, and especially CZOP and cefpirome (CPR) showed the strongest activity (MIC90: < or = 0.125 microg/mL). Quinolone resistant E. coli [MIC of ciprofloxacin (CPFX): > or =4 microg/mL] was detected at frequency of 15.7%, which was higher than that in the last year. Against Klebsiella pneumoniae, meropenem (MEPM) showed the strongest activity and next, the antibacterial activity of CRMN and CZOP was good. The antibacterial activity of the other cephems, however, significantly decreased, compared with that evaluated in last year. Against Serratia marcescens, MEPM had the strongest antibacterial activity. Against Proteus mirabilis, MEPM and CRMN showed the strongest activity and prevented the growth of all strains with 0.125 microg/mL or less. Nest, cefmenoxime (CMX), ceftazidime (CAZ), cefixime (CFIX), cefpodoxime (CPDX), CPR, CZOP, and cefditoren (CDTR) showed a strong activity. The antibacterial activity of the drugs to Pseudomonas aeruginosa was generally low, and MIC90 of all the drugs was ranged from 32 to < or = 256 microg/mL except IPM and amikacin (AMK) having 16 microg/mL. The antibacterial activity of CZOP was relatively good (MIC50: 2 microg/mL).

Drug Resistance, Microbial↗
PubMed2005

[Comparative studies on activities of antimicrobial agents against causative organisms isolated from patients with urinary tract infections (2003). II. Background of patients].

Seven hundred and nineteen bacterial strains isolated from 565 patients diagnosed as having urinary tract infections (UTIs) in 14 institutions in Japan were collected between August 2002 and July 2003. The frequency of bacteria isolation divided with patient clinical background was compared. The clinical background investigated included sex, age, type of infections, timing of antibiotics administration, and presence or absence of surgery affecting a decrease in defense against infection. The bacterial strains were divided with the age and sex of the patients and the types of infections. In males, the number of patients aged less than 50 years was few and the complicated UTIs without indwelling catheter was observed most frequently. Number of patients aged 20-39 years was greater in female than male. In all of ages except 0-9 and 70-79 years, the ratio of the uncomplicated UTIs was high, accounting for 44.4-91.7% of all types of infections. In the present time, the bacteria most frequently isolated were Escherichia coli, Pseudomonas aeruginosa and Enterococcus faecalis also were relatively frequently isolated. E. coli was most frequently isolated from the uncomplicated UTIs, and P. aeruginosa and E. faecalis were frequently isolated from the complicated UTIs with indwelling catheter. With respect to the relation of these results to the age of the patients, in the uncomplicated UTIs, the isolation frequency of E. coli was the highest in all age groups, accounting for 40% or higher. In the complicated UTIs without indwelling catheter, the isolation frequency of E. coli decreased with aging of the patients but still was the highest in all age groups. In the complicated UTIs with indwelling catheter, the isolation frequency of E. coli was lower than in the uncomplicated UTIs in all age groups and P. aeruginosa and E. faecalis were more frequently isolated. In comparison of causative bacteria in UTIs between before and after the administration of antibiotics, P. aeruginosa increased after the administration in any types of UTIs. In comparison of causative bacteria in UTIs with or without surgery, E. coli was more frequently isolated in the patients without surgery, while P. aeruginosa and E. faecalis were more frequently isolated in the patients with surgery in any UTIs.

Adolescent↗
PubMed2005

[Comparative studies on activities of antimicrobial agents against causative organisms isolated from patients with urinary tract infections (2003). III. Secular changes in susceptibility].

The bacteria (Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Klebsiella spp. and Pseudomonas aeruginosa) isolated from 565 patients diagnosed as urinary tract infections (UTIs) in 14 institutions in Japan were collected between August 2003 and July 2004. The susceptibilities of these bacteria to various antimicrobial agents were examined. The bacteria were divided into 2 groups consisting of uncomplicated UTIs and complicated UTIs (with and without indwelling catheter) based on their isolation origins. The results were compared with those obtained between 1994 and 2002. The drug sensitivity of S. aureus in this year was similar to those in up to the previous years and S. aureus showed the best susceptibility to vancomycin. The drug sensitivity of E. faecalis in this year also was similar to those in up to the previous years. The drug sensitivity of E. coli in this year was generally good except penicillins and was similar to those in up to the previous years. Among cephems, cefozopran (CZOP) and cefpirome (CPR) showed the highest potency activity (MIC90: < or = 0.125 microg/mL). An antibacterial activity of cefotiam (CTM) was stable for 10 years and was fine (MIC0: < or = 0.5 microg/mL). The sensitivity of E. coli to carbapenems and carumonam (CRMN) also was good like to CZOP. The sensitivity of the complicated UTIs group to quinolones, however, has decreased after 2000 and it was suggested that the resistance to the drug has developed. Kiebsiella spp. showed a decrease in the susceptibility to some of cephems. The drugs indicating a big decrease in the sensitivity were cefazolin, CTM, cefaclor, and cefpodoxime. Imipenem, carbapenems, also indicated a decrease in the sensitivity. The susceptibility of the strain to the other drugs was similar to that in up to the previous years. Among them, CZOP maintained good susceptibility (MIC90: > or = 0.125 microg/mL against uncomplicated UTIs, 0.25 microg/mL against complicated UTIs) like meropenem. The drug sensitivity of P. aeruginosa was generally low and was not much different from that in up to the previous years.

Anti-Infective Agents↗
PubMed2005

[Nationwide surveillance of parenteral antibiotics containing meropenem activities against clinically isolated strains in 2004].

The antibacterial activity of meropenem (MEPM) and other parenteral antibiotics against clinical isolates of 907 strains of Gram-positive bacteria, 1790 strains of Gram-negative bacteria, and 192 strains of anaerobic bacteria obtained from 30 medical institutions during 2004 was measured. The results were as follows; 1. MIC90 of MEPM for almost all of enterobacteriaceae and Haemophilus influenzae were 4-fold to 32-fold lower than those of other carbapenems. MEPM was more active than other carbapenem antibiotics against Gram-negative bacteria, especially against enterobacteriaceae and H. influenzae. MEPM were active against most of the species tested in Gram-positive and anaerobic bacteria, except for multi-drug resistant strains including methicillin-resistant Staphylococcus aureus. 2. As for Pseudomonas aeruginosa, imipenem (IPM) showed high cross-resistant rate againt meropenem-resistant P. aeruginosa (87.9%). MEPM showed low cross-resistant rate both againt IPM-resistant P. aeruginosa (49.2%) and ciprofloxacin-resistant P. aeruginosa (38.0%). 3. The proportion of extended-spectrum beta-lactamase (ESBL) strains was 3.1% (4 strains) in Escherichia coli, 8.0% (2 strains) in Citrobacter koseri, 2.5% (3 strains) in Klebsiella pneumoniae, 2.5% (2 strains) in Enterobacter cloacae, 0.9% (1 strains) in Serratia marcescens, and 2.2% (2 strains) in Proteus mirabilis. The proportion of metallo-beta-lactamase strains was 1.6% (5 strains) in P. aeruginosa. 4. Of all species tested, Peptostreptococcus spp. was the only species, which MIC90 of MEPM was more than 4-fold higher than that in our previous study using clinical isolates during 2002 (0.25 microg/ml --> 1 microg/ml). Therefore, there is almost no siginificant decrease in susceptibility of clinical isolates to meropenem. In conclusion, the results from this surveillance study suggest that MEPM retains its potent and broad antibacterial activity and therefore is a clinically useful carbapenem at present, 9 years after available for commercial use.

Anti-Infective Agents↗
PubMed2004

[Dengue fever].

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Acetaminophen↗
PubMed2004

Evaluation of a rapid antigen detection test for Neisseria gonorrhoeae in urine sediment for diagnosis of gonococcal urethritis in males.

We evaluated a rapid antigen detection method with an immunochromatographic assay for Neisseria gonorrhoeae (NOW Gonorrhea Test) by using urine samples from patients with urethritis to diagnose gonococcal infection in males. Among 58 male patients who underwent urethral swab culture, 34 cases (58.6%) were found to have N. gonorrhoeae infection. The sensitivity and specificity of the NOW Test compared with the results of standard culture were 94.1% (32/34) and 95.8% (23/24), respectively. The predictive values of positive NOW and negative NOW were 96.9% (32/33) and 92.0% (23/25), respectively. The detection limit of this assay was determined as 5 x 10(4) cfu/ml using N. gonorrhoeae suspension as an antigen. In contrast to standard cultures, gonococcal antigens in specimens were still detectable by this method up to 45 h of storage at either room temperature or 4 degrees C. Considering the rapidity and ease of this method, our results suggest that the NOW method might be a useful and reliable diagnostic screening tool for gonococcal urethritis.

Antigens, Bacterial↗
PubMed2004

Multiplex PCR for the simultaneous detection of Chlamydia pneumoniae, Mycoplasma pneumoniae and Legionella pneumophila in community-acquired pneumonia.

A multiplex polymerase chain reaction (PCR) was developed for the simultaneous detection of Chlamydia pneumoniae, Mycoplasma pneumoniae and Legionella pneumophila. Oligonucleotide primers for the amplification of the DNA of these three organisms were optimized for use in combination in the same reaction. PCR products were detected by the Micro-Chip Electrophoresis Analysis System. Clinical samples were obtained from 208 community-acquired pneumonia (CAP) patients who were participants in a multicenter CAP surveillance study performed at seven medical schools and their affiliate hospitals in Japan. No significant differences in the sensitivity of each primer set were observed when tested in both the multiplex and monoplex PCR assays. Our multiplex PCR was able to reliably detect 10 copies/100 microl of each of the three pathogen DNAs. Of the panel of 208 samples, 14 of 15 C. pneumoniae, 10 of 10 M. pneumoniae, eight of eight L. pneumophila and 165 of 176 negative samples were correctly identified. Eleven cases who were the multiplex PCR positive and conventional method negative were observed. The PCR findings were of possible significance in at least four of these patients. Our multiplex PCR assay could potentially be used as a diagnostic and epidemiological tool. Further prospective studies are needed to establish its clinical usefulness.

Adolescent↗
PubMed2004

Protective effect of ethyl-3-(3-dimethyl aminopropyl)urea dihydrochloride (EDU) against LPS-induced death in mice.

Evaluation of anti-adhesive gels and bioresorbable films in animal models of intra-abdominal infection has shown that a product of the cross-linking reaction between hyaluronic acid (HA) and CM-cellulose, 1-ethyl-3-(3-dimethyl aminopropyl)urea dihydrochloride (EDU), has immunomodulatory properties. The effects of EDU were evaluated by using an endotoxin-induced shock mouse model. Pre-treatment of mice with EDU (50 mg kg(-1)) in DMSO resulted in a significant reduction in mortality following injection of LPS, compared to vehicle (DMSO) pre-treatment alone. Serum levels of TNF-alpha, IL1beta and IFN-gamma in EDU-treated mice were significantly lower than those in vehicle-treated mice. Nitric oxide (NO) concentrations in the sera of mice after inoculation with LPS were significantly lower in the EDU-treated group than in the vehicle-treated group at various time-points. In contrast, EDU pre-treatment was associated with an enhanced IL10 response after LPS injection, compared to vehicle pre-treatment alone. In vitro studies revealed that IL10 production by RAW 264.7 macrophages, elicited by LPS, was increased significantly when EDU was added to the culture medium. These results suggest that the protective effect of EDU during LPS-induced shock in mice is the result of inhibition of proinflammatory cytokines and NO production and an enhanced IL10 response.

Animals↗
PubMed2004

Legionella-induced acute lung injury in the setting of hyperoxia: protective role of tumour necrosis factor-alpha.

Among the main characteristics of Legionella pneumophila pneumonia are acute lung injury and severe hypoxemia. Although high oxygen supplementation is a valuable supportive therapy in these patients, oxygen itself is known to be a risk factor for acute lung injury. The effects of hyperoxia on lung injury of mice with Legionella pneumonia were examined. Hyperoxia treatment reduced survival of the infected mice in an oxygen concentration- and exposure time-dependent manner. The enhanced lethality was associated with an increase in total lung weight and apoptosis markers, but not with bacterial burden in the lungs. Hyperoxia decreased the levels of the antioxidant glutathione (GSH) in infected lungs. Exogenous tumour necrosis factor-alpha (TNF-alpha) improved the survival of infected mice kept under hyperoxia. TNF-alpha effects were associated with restoration of total lung weight and histone DNA and GSH levels on day 2, whereas the lung bacterial burden did not differ significantly. Moreover, upregulation of GSH by TNF-alpha was observed in the lungs of mice without infection. These results demonstrate that hyperoxia exacerbates L. pneumophila pneumonia. The data suggest that TNF-alpha may be a potential therapeutic candidate for these individuals, not only through modulating host antibacterial systems, but also by mediating induction of the antioxidant GSH.

Animals↗
PubMed2004

Relation of cigarette smoking and alcohol use to colorectal adenomas by subsite: the self-defense forces health study.

While smoking has consistently been shown to be related to increased risk of colorectal adenomas, few studies have addressed the association between smoking and site-specific colorectal adenomas. The reported association between alcohol use and colorectal adenomas has been inconsistent. We evaluated risks of adenomas at the proximal colon, distal colon, and rectum in relation to cigarette smoking and alcohol use, and their interaction. Subjects were 754 cases with histologically proven colorectal adenomas and 1547 controls with normal colonoscopy among male officials of the Self-Defense Forces (SDF) undergoing total colonoscopy at two SDF hospitals. Statistical adjustment was made for hospital, rank, body mass index, physical activity, and either smoking or alcohol drinking. Cigarette smoking was significantly associated with an increased risk of adenomas, regardless of the location of the adenomas, but the increased risk associated with smoking was more pronounced for rectal adenomas. Alcohol use was associated with moderately increased risks of distal colon and rectal adenomas, but not of proximal colon adenomas. Cigarette smoking, but not alcohol drinking, was associated with greater increases in the risk of large adenomas and of multiple adenomas across the colorectum. There was no measurable interaction of cigarette smoking and alcohol drinking on colorectal adenomas. The findings corroborate an increased risk of colorectal adenomas associated with smoking and a weak association between alcohol use and colorectal adenomas. Further studies are needed to confirm whether smoking is more strongly related to rectal adenomas, large adenomas, or multiple adenomas.

Adenoma↗
PubMed2004

Pharmacodynamics of S-3578, a novel cephem, in murine lung and systemic infection models.

S-3578 is a novel beta-lactam with enhanced activity against drug-resistant gram-positive cocci such as methicillin-resistant Staphylococcus aureus (MRSA). We used murine penicillin-resistant Streptococcus pneumoniae lung infection and neutropenic murine systemic MRSA infection models to determine the pharmacokinetic (PK)-pharmacodynamic (PD) parameter that best correlated with efficacy. Pharmacokinetic studies revealed that the maximum concentration in serum/dose values for S-3578 and cefepime in plasma in the lung infection model were 1.21 to 1.54 and 0.97 to 1.29, respectively; those for S-3578 in plasma in the systemic infection model were 0.78 to 1.02. The area under the concentration-time curve (AUC)/dose values for S-3578 and cefepime in plasma in the lung infection model were 0.98 to 1.13 and 0.77 to 1.04, respectively, and those for S-3578 in plasma in the systemic infection model were 1.03 to 1.11. The half-lives of S-3578 and cefepime in plasma in the lung infection model were 0.29 to 0.38 and 0.29 to 0.34, respectively, and those of S-3578 in plasma in the systemic infection model were 0.40 to 0.61. The time above the MIC was the PK-PD parameter that best correlated with efficacy in the murine lung infection model (R(2) = 84 and 92% for S-3578 and cefepime in plasma, respectively). There was a twofold increase in the dose of S-3578 in the systemic infection model compared to that in the pneumonia model, yet the AUCs were the same. This may be due to the different MICs for the two pathogens.

Animals↗
PubMed2004

Role of a mutation at position 167 of CTX-M-19 in ceftazidime hydrolysis.

CTX-M-19 is a recently identified ceftazidime-hydrolyzing extended-spectrum beta-lactamase, which differs from the majority of CTX-M-type beta-lactamases that preferentially hydrolyze cefotaxime but not ceftazidime. To elucidate the mechanism of ceftazidime hydrolysis by CTX-M-19, the beta-lactam MICs of a CTX-M-19 producer, and the kinetic parameters of the enzyme were confirmed. We reconfirmed here that CTX-M-19 is also stable at a high enzyme concentration in the presence of bovine serum albumin (20 micro g/ml). Under this condition, we obtained more accurate kinetic parameters and determined that cefotaxime (k(cat)/K(m), 1.47 x 10(6) s(-1) M(-1)), cefoxitin (k(cat)/K(m), 62.2 s(-1) M(-1)), and aztreonam (k(cat)/K(m), 1.34 x 10(3) s(-1) M(-1)) are good substrates and that imipenem (k(+2)/K, 1.20 x 10(2) s(-1) M(-1)) is a poor substrate. However, CTX-M-18 and CTX-M-19 exhibited too high a K(m) value (2.7 to 5.6 mM) against ceftazidime to obtain their catalytic activity (k(cat)). Comparison of the MICs with the catalytic efficiency (k(cat)/K(m)) of these enzymes showed that some beta-lactams, including cefotaxime, ceftazidime, and aztreonam showed a similar correlation. Using the previously reported crystal structure of the Toho-1 beta-lactamase, which belongs to the CTX-M-type beta-lactamase group, we have suggested characteristic interactions between the enzymes and the beta-lactams ceftazidime, cefotaxime, and aztreonam by molecular modeling. Aminothiazole-bearing beta-lactams require a displacement of the aminothiazole moiety due to a severe steric interaction with the hydroxyl group of Ser167 in CTX-M-19, and the displacement affects the interaction between Ser130 and the acidic group such as carboxylate and sulfonate of beta-lactams.

Aztreonam↗
PubMed2004

Intraperitoneal injection of lipopolysaccharide induces dynamic migration of Gr-1high polymorphonuclear neutrophils in the murine abdominal cavity.

Intraperitoneal injection of lipopolysaccharide (LPS; 100 microg) in mice resulted in the disappearance of almost all proteose peptone-induced polymorphonuclear neutrophils (PMNs) with high-level fluorescence for the cell surface marker Gr-1 (Gr-1(high)) at 15 min postinjection, followed by doubling of their proportion at 30 min postinjection. High staining levels of 3'-acetyl-2'-carboxyl-6',7'-(dihyropyran-2'-one)-5 or 6-carboxyfluorescein diacethoxylmethyl ester-labeled PMNs injected into the peritoneal cavity were detected in mesenteric lymph nodes 15 min postinjection of LPS. Therefore, the time of decrease of Gr-1(high) PMNs coincided with that of the increase in cell accumulation in mesenteric lymph nodes. Since milk fat globule-EGF factor 8 (MFG-E8), which is secreted by macrophages, bound many PMNs exhibiting Gr-1(high) and Gr-1(medium) at 30 min postinjection of LPS, the staining level of annexin V on those cells was very low because its binding site is the same as the receptor for MFG-E8. At 60 min postinjection of LPS, the proportion of Gr-1(high) PMNs decreased, and almost all Gr-1(medium) PMNs tended to shift to the right compared with those at 30 min postinjection. The geomeans of Toll-like receptor 4 (TLR4) expression on PMNs at 15, 30, and 60 min postinjection of LPS were 63, 66, and 24%, respectively, compared with that on normal PMNs, indicating that the expression of TLR4 decreases in response to exposure to LPS. Our results suggest that LPS induced PMN death and that many PMNs expressing Gr-1(high) undergo apoptosis 180 min postinjection of LPS.

Abdominal Cavity↗