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Keiko Hasegawa

Publications and source records attributed to Keiko Hasegawa.

At least 19 recordsLinked to original sources

High prevalence of type b beta-lactamase-non-producing ampicillin-resistant Haemophilus influenzae in meningitis: the situation in Japan where Hib vaccine has not been introduced.

OBJECTIVES: To study yearly changes in resistance and to identify ftsI mutations in beta-lactamase-non-producing ampicillin-resistant (BLNAR) and TEM-1 beta-lactamase-producing amoxicillin/clavulanic acid-resistant (BLPACR) isolates of Haemophilus influenzae from patients with meningitis. METHODS: Between January 2000 and December 2004, we received 621 isolates of H. influenzae from 285 member institutions of the Nationwide Surveillance Study Group for Bacterial Meningitis. All isolates were analysed by PCR to identify resistance genes and tested for susceptibility to beta-lactams. The ftsI gene was sequenced in all BLNAR and BLPACR isolates. RESULTS: All but four isolates were of serotype b. The isolates could be divided into six classes, namely beta-lactamase-non-producing ampicillin-susceptible (25.0%), TEM-1 beta-lactamase-producing ampicillin-resistant (11.0%), beta-lactamase-non-producing low-level ampicillin-resistant with N526K or R517H substitution in the ftsI gene (30.4%), BLNAR with an S385T substitution together with either N526K or R517H substitution in ftsI (22.2%), BLPACR-I with either a N526K or R517H substitution in ftsI (9.5%) and BLPACR-II with an S385T substitution together with either a N526K or R517H substitution in ftsI (1.9%). The prevalence of BLNAR has increased rapidly, from 5.8% in 2000 to 34.5% in 2004. All BLNAR and BLPACR-II strains were classified into nine subgroups on the basis of substitution patterns in the ftsI gene. The MICs of cephalosporin antibiotics for H. influenzae transformants into which the ftsI genes from BLNAR strains of each of the nine subgroups were introduced increased to varying degrees depending on the mutations. CONCLUSIONS: The results suggest that introduction of H. influenzae type b (Hib) vaccination into infants and children is necessary for the prevention of severe Hib infections in Japan.

Amino Acid Substitution↗

[Trends in pediatric bacterial meningitis in Japan (2003-2004)].

We surveyed the epidemiology of pediatric bacterial meningitis between January 2003 and December 2004 in Japan, with the following results: Bacterial meningitis cases numbered 233 (132 boys, 98 girls, and 3 unidentified), equivalent to 1.13-1.6 children of 1000 hospitalized in pediatrics per year. The age distribution for the infections was the highest under 1 year of age, decreasing with increasing age. Haemophilus influenzae was the most common pathogen, followed by Streptococcus pneumoniae, group B streptococcus, and Escherichia coli. The relationship between causactive pathogens and age distribution was as follows: group B. streptococcus and E. coli were major pathogens below 4 months of age and H. influenzae and S. pneumoniae were major pathogens above 4 months of age. Susceptibility tests at each facility demonstrated that 65.0% of H. influenzae isolates and 83.0% of S. pneumoniae isolates in 2004 were drug-resistant. Ampicillin and cephem antibiotics are currently effective against GBS, E. coli and Listeria so a combination of ampicillin and cephem antibiotics is used first line at many facilities for patients below 4 months of age. A combination of carbapenem which showed effective against PRSP and cephem which showed effective against H. influenzae is the first choice in childhood bacterial meningitis for patients above 4 months of age.

Ampicillin↗

Simultaneous detection of pathogens in clinical samples from patients with community-acquired pneumonia by real-time PCR with pathogen-specific molecular beacon probes.

In this study, real-time PCR with pathogen-specific molecular beacons (MB) and primers was evaluated for prediction of community-acquired pneumonia (CAP) causative agents, detecting six main CAP agents, Streptococcus pneumoniae, Haemophilus influenzae, Mycoplasma pneumoniae, Chlamydophila pneumoniae, Legionella pneumophila, and Streptococcus pyogenes, simultaneously. The PCR assay was evaluated for fresh clinical specimens from infants and children (n = 389) and from adults (n = 40). The MB probes and primers are both pathogen specific, namely, the lytA gene for S. pneumoniae, the mip gene for L. pneumophila, and 16S rRNA genes for the remaining four organisms. DNA extraction of clinical specimens was performed with a commercially available EXTRAGEN II kit, and amplification was performed with Stratagene Mx3000P. The limit of detection for these pathogens ranged from 2 copies to 18 copies. The whole process from DNA extraction to the analysis was finished in less than 2 h. The obtained sensitivity and specificity of this real-time PCR study relative to those of conventional cultures were as follows: 96.2% and 93.2% for S. pneumoniae, 95.8% and 95.4% for H. influenzae, 100% and 100% for S. pyogenes, and 100% and 95.4% for M. pneumoniae, respectively. The sensitivity and specificity for M. pneumoniae relative to those of a serologic assay were 90.2% and 97.9%, respectively. In six clinical samples of C. pneumoniae, the real-time PCR gave positive predictable values, and in those cases, elevation of the titer value was also observed. In conclusion, we demonstrated that a real-time PCR assay with pathogen-specific MB is useful in identifying CAP causative agents rapidly and in examining the clinical course of empirical chemotherapy in a timely manner, supporting conventional culture methods.

Child, Preschool↗

Assessment of real-time PCR for diagnosis of Mycoplasma pneumoniae pneumonia in pediatric patients.

We developed a real-time PCR to detect Mycoplasma pneumoniae with a primer set designed for the 16S rRNA gene. Clinical samples (n=937) were collected from children with community-acquired pneumonia between April 2002 and March 2004 at 12 Japanese medical institutions. Sensitivity of real-time PCR was calculated as 10 colony-forming units per reaction tube using a pMP01 plasmid carrying a 225-bp target DNA fragment of the 16S rRNA gene in M. pneumoniae M129, a standard strain. Results, obtained within 2 h, were compared with those of conventional culture and serologic methods. Of all cases tested, 151 (16.4%) and 129 (13.8%) were positive for M. pneumoniae by real-time PCR and by culture, respectively. Among the 151 cases, almost all of those tested serologically by passive agglutination showed a rise in M. pneumoniae antibody titre between acute and convalescent sera. We conclude that this real-time PCR can identify M. pneumoniae rapidly and fulfills the need for rapid identification, high sensitivity, and high specificity.

Adolescent↗

[Blood lactate concentrations as predictors of outcome in serious hemorrhagic shock patients].

BACKGROUND: There is no useful predictor of treatment preventing progress from hemorrhagic shock to systemic inflammatory response syndrome or disseminated intravascular coagulation. Recent reports have shown that blood lactate levels could be related to outcome of critically ill patients including those with septic shock. METHODS: We retrospectively investigated the relation between blood lactate concentrations and outcomes of 19 patients with Hb < or = 5 g x dl(-1) caused by preoperative or intraoperative bleeding. RESULTS: There were 15 survivors and 4 nonsurvivors from hemorrhagic shock. No significant difference was found in the highest intraoperative blood lactate concentrations between survivors and nonsurvivors. However, survivors had significantly lower blood lactate concentrations immediately after operation and after recovery from shock. CONCLUSIONS: Blood lactate concentrations and especially their time courses have a strong relation with survival from hemorrhagic shock and can be reliable clinical predictors of therapy.

Adolescent↗

[Aggravation of congestive heart failure after cesarean section in a patient with undiscovered hyperthyroidism].

A 27-year-old woman with toxicity of pregnancy and congestive heart failure underwent an emergency cesarean section. In spite of antihypertensive drugs, blood pressure and heart rate were high preoperatively. She coughed many times and SpO2 was 88%. Circulatory state became stable without antihypertensive drugs under combined spinal-epidural anesthesia and continuous intravenous infusion of propofol intraoperatively. After surgery, blood pressure and heart rate became elevated again and congestive heart failure became worse. She was diagnosed as hyperthyroidism by postoperative laboratory examination. If we had discovered her hyperthyroidism, her symptoms of congestive heart failure would not have become worse. We should be more careful about hyperthyroidism in pregnancy because it is not rare.

Adult↗

Antibiotic susceptibility according to genotype of penicillin-binding protein and macrolide resistance genes, and serotype of Streptococcus pneumoniae isolates from community-acquired pneumonia in children.

OBJECTIVES: Antibiotic susceptibilities, genes mediating beta-lactam and macrolide resistance, and serotypes were analysed for strains of Streptococcus pneumoniae. METHODS: A total of 392 strains of S. pneumoniae were isolated from paediatric patients with community-acquired pneumonia between May 2002 and 2004. All strains were classified into six genotype patterns according to the mutations found in the pbp1a, pbp2x and pbp2b genes identified by PCR. These results are represented by adding 'g', indicating genotypic identification. RESULTS: Thirty-nine per cent of the isolates showed mutations in either one or two PBP genes (gPISP, where PISP stands for penicillin-intermediate resistant S. pneumoniae) and 52.3% had mutations in three genes (gPRSP, where PRSP stands for penicillin-resistant S. pneumoniae). The majority of the strains had a macrolide resistance gene: mefA, (30.6%); ermB, (48.5%); or both mefA and ermB, (7.7%). The most frequent serotypes of these strains were: 6B (23.2%), 23F (17.6%), 19F (17.3%), 14 (10.5%) and 6A (8.2%). Serotypes of the seven-valent conjugate vaccine covered 70.9% of all isolates, and 89.8% of gPRSP. Serotypes of the strains with cefotaxime MICs of > or =2 mg/L were almost all of a vaccine type. CONCLUSIONS: The results suggest that introduction of conjugate vaccines into infants and children is necessary for the prevention of pneumococcal infections in Japan.

Aminoacyltransferases↗

Ultrasonographic findings of facial dysmorphism in Wolf-Hirschhorn syndrome.

Wolf-Hirschhorn syndrome has characteristic craniofacial dysmorphism with severe fetal growth restriction. We present a case that revealed facial dysmorphism characteristic of Wolf-Hirschhorn syndrome with two- and three-dimensional ultrasonography. The facial dysmorphic features in the present case were dolichocephaly; high forehead; large rectangular nose continuing to the eyebrows; hypertelorism; short philtrum; carp-shaped mouth; microretrognathia; and large, simply modeled, low-set ears. Chromosome analysis of amniotic fluid cells was 46,XX,del(4)(p15.2), confirming the ultrasonographic result. Examination with two- and three-dimensional ultrasonography is useful to observe the face of fetuses with severe intrauterine growth restriction to diagnose multiple congenital anomaly syndromes.

Abnormalities, Multiple↗

Elimination of CD4(+)CD25(+) T cell accelerates the development of glomerulonephritis during the preactive phase in autoimmune-prone female NZB x NZW F mice.

The role of CD4(+)CD25+ T cell in glomerulonephritis (GN) development during the preactive phase was investigated in autoimmune-prone female NZB x NZW F1 (B/WF1) mice. The administration of anti-mouse CD25+ T-cell monoclonal antibody (PC61.5) 3 days after birth induced the development of GN with an increase in IgG2a antinuclear antibody, productions of IL-6 and IFN-gamma, whereas TGF-beta1 production decreased, compared to untreated control mice. The present study results suggest that CD4(+)CD25+ T cells may, at least in part, downregulate the development of GN during the preactive phase in B/WF1 mice.

Acute Disease↗

Prenatal diagnosis and management for a large fetal cardiac tumor complicated with hydrops fetalis.

Fetal cardiac tumor is a rare disease, and its prognosis varies in relation to the complications such as arrhythmia and out-flow obstruction. Hydrops fetalis is one of severe complications that result in an unfavorable outcome. A case is presented herein of a large fetal cardiac tumor diagnosed at 28 weeks gestation. At 30 weeks gestation, the fetus complicated with hydrops fetalis because of impaired cardiac function. Increased peak systolic velocity in the ascending aorta and marked reversed flow in the ductus venosus were observed. Oral digoxin therapy was administered to the mother as a cardiotonic agent and the hydropic condition was immediately diminished. After normal delivery, the cardiac tumor gradually decreased in size and the infant developed normally, but required an antiarrhythmic drug. The case indicates that the in utero digoxin therapy could be a choice for hydrops fetalis caused by cardiac tumor.

Adult↗

In vitro activity of tebipenem, a new oral carbapenem antibiotic, against penicillin-nonsusceptible Streptococcus pneumoniae.

The in vitro activity of tebipenem (TBM), a new oral carbapenem antibiotic, against Streptococcus pneumoniae clinical isolates (n = 202) was compared with those of 15 reference agents. The isolates were classified into five genotypic classes after PCR identification of abnormal pbp1a, pbp2x, and pbp2b genes: (i) penicillin-susceptible S. pneumoniae (PSSP) isolates with no abnormal pbp genes (n = 34; 16.8%), (ii) genotypic penicillin-intermediate S. pneumoniae (gPISP) isolates with only an abnormal pbp2x gene [gPISP (2x)] (n = 48; 23.8%), (iii) gPISP isolates with abnormal pbp1a and pbp2x genes (n = 32; 15.8%), (iv) gPISP isolates with abnormal pbp2x and pbp2b genes (n = 16; 7.9%), and (v) genotypic penicillin-resistant S. pneumoniae (gPRSP) isolates with three abnormal pbp genes (n = 72; 35.6%). The majority of the strains tested had mefA (n = 59; 29.2%) or ermB (n = 91; 45%) gene-mediating macrolide resistance. For these isolates the MIC at which 90% of isolates are inhibited was significantly lower for TBM than for the reference oral antibiotics, as follows: 0.002 microg/ml for PSSP, 0.004 mug/ml for gPISP (2x), 0.016 microg/ml for gPISP (isolates with abnormal pbp1a and pbp2x genes and isolates with abnormal pbp2x and pbp2b genes), and 0.063 microg/ml for gPRSP. In addition, TBM showed excellent bactericidal activity against gPRSP isolates, which exhibited a 3-log(10) decrease within 2 h when they were incubated with a concentration greater than or equal to the MIC. Inhibition of cell wall synthesis toward the long axis and subsequent cell lysis were observed by scanning electron microscopy after a short-term exposure to TBM, unlike the effects seen with cephalosporins. These data suggest that TBM has potent activity against multidrug-resistant S. pneumoniae, the causative pathogen of community-acquired respiratory tract infections.

Administration, Oral↗

Emergence of macrolide-resistant Mycoplasma pneumoniae with a 23S rRNA gene mutation.

A total of 195 Mycoplasma pneumoniae strains were isolated from 2,462 clinical specimens collected between April 2002 and March 2004 from pediatric outpatients with respiratory tract infections. Susceptibilities to six macrolide antibiotics (ML), telithromycin, minocycline, levofloxacin, and sitafloxacin were determined by the microdilution method using PPLO broth. A total of 183 M. pneumoniae isolates were susceptible to all agents and had excellent MIC90s in the following order: 0.00195 microg/ml for azithromycin and telithromycin, 0.0078 microg/ml for clarithromycin, 0.0156 microg/ml for erythromycin, 0.0625 microg/ml for sitafloxacin, 0.5 microg/ml for minocycline, and 1 microg/ml for levofloxacin. Notably, 12 ML-resistant M. pneumoniae strains were isolated from patients with pneumonia (10 strains) or acute bronchitis (2 strains). These strains showed resistance to ML with MICs of >or=1 microg/ml, except to rokitamycin. Transition mutations of A2063G or A2064G, which correspond to A2058 and A2059 in Escherichia coli, in domain V on the 23S rRNA gene in 11 ML-resistant strains were identified. By pulsed-field gel electrophoresis typing, these strains were classified into groups I and IIb [corrected] as described previously (A. Cousin-Allery, A. Charron, B. D. Barbeyrac, G. Fremy, J. S. Jensen, H. Renaudin, and C. Bebear, Epidemiol. Infect. 124:103-111, 2000). These findings suggest that excessive usage of MLs acts as a trigger to select mutations on the corresponding 23S rRNA gene with the resultant occurrence of ML-resistant M. pneumoniae. Monitoring ML susceptibilities for M. pneumoniae is necessary in the future.

Adolescent↗

Application of PCR for Mycoplasma pneumoniae detection in children with community-acquired pneumonia.

Between April 2002 and March 2003, to detect Mycoplasma pneumoniae by polymerase chain reaction (PCR), a primer set designed for the 16S rRNA gene was used to examine clinical samples from 369 children with community-acquired pneumonia. Samples were collected from 12 Japanese institutions participating in a study group concerning acute respiratory infectious diseases. The sensitivity of primers--2 CFU per reaction tube, using M. pneumoniae M129, a standard strain--was calculated to represent 1.1 x 10(3) M. pneumoniae organisms adherent to the tip of the swab used to collect clinical samples. Results for PCR were obtained within 2.6 h. Cases identified by PCR, cultures, and serologic tests were 68 (18.4%), 53 (14.4%), and 76 (20.6%) respectively. Among 57 PCR-positive patients tested serologically, 56 showed a significant elevation or rise in antibody titer. PCR positivity was high among patients prescribed beta-lactam antibiotics (86.7%) or no antibiotic (87.0%) before PCR analysis, but was low among patients receiving macrolides, new quinolones, or tetracyclines (37.5%). We concluded that the PCR constructed by us had a high probability for confirming a diagnosis of M. pneumoniae pneumonia and for guiding antibiotic choice for patients not yet treated.

Adolescent↗

[Molecular epidemiology of Haemophilus influenzae strains isolated from patients with meningitis during 1999 to 2003].

A total of 535 Haemophilus influenzae strains from 226 Japanese institutions participating in the Nationwide Surveillance Study Group for Bacterial Meningitis were sent to our laboratory during 1999 to 2003. All strains were analyzed by PCR to identify the beta-lactam resistance genes, and their susceptibilities to beta-lactam agents were determined. These strains were classified into 6 genotype patterns and MIC90 values for ampicillin (ABPC): (i) beta-lactamase nonproducing, ABPC susceptible (BLNAS) strains and lacked all resistance genes (27.7% of isolates; MIC90, 0.5 microg/ml); (ii) beta-lactamase producing, ABPC resistant (BLPAR) strains (12.9%, 16 microg/ml); (iii) beta-lactamase nonproducing, ABPC resistant (Low-BLNAR) strains with a Asn526Lys amino acid substitution in ftsI gene encoding PBP3 (31.2%, 2 microg/ml); (iv) beta-lactamase nonproducing, ABPC resistant (BLNAR) strains with Ser385Thr and Asn526Lys substitutions in ftsI (17.2%, 8 microg/ml); (v) amoxicillin/clavlanic acid resistant (BLPACR I) strains, having beta-lactamase gene and a Asn526Lys amino acid substitution in ftsI (9.2%, 32 microg/ml); and (vi) amoxicillin/clavlanic acid resistant (BLPACR II), having beta-lactamase gene and ftsI substitutions as for BLNAR strains (1.9%, 64 microg/ml). All but 4 strains were serotype b. The prevalence of BLNAR strains has increased exponentially: 0% (n = 0/41) in 1999, 5.8% (n = 4/69) in 2000, 14.1% (n = 19/139) in 2001, 20.1% (n = 32/159) in 2002, and 29.1% (n = 37/127) in 2003. The MIC90s of BLNAR isolates except for ABPC were as follows: piperacillin, 0.125 microg/ml; ceftriaxone, 0.25 microg/ml; meropenem, 0.5 microg/ml; cefotaxime, 1 microg/ml; panipenem, 2 microg/ml; cefozopran, 16 microg/ml; and cefotiam, 64 microg/ml. To prevent such resistance from increasing, expedited vaccination, correct identification of the BLNAR molecularly, and the proper selection of proper antibiotics based on PK/PD must be taken.

Adult↗

[The trend of childhood bacterial meningitis in Japan (2000-2002)].

We surveyed the epidemiology of bacterial meningitis in pediatrics between July 2000 and December 2002 in Japan and obtained the following results.: The number of cases of bacterial meningitis was 316 (182 boys and 134 girls), which was equivalent to 1.1-1.7 children out of 1,000 hospitalized those in pediatrics per year. The age-distribution for the infections was the highest under 1 year of age and it decreased as the age increased. Haemophilus influenzae was the most common pathogen causing the infections, followed by Streptococcus pneumoniae, group B streptococcus, and Escherichia coli. Relationship between causing pathogens and age-distribution was as follows: group B streptococcus and E. coli were major pathogens under 4 months of age and H. influenzae and S. pneumoniae were major pathogens over 4 months of age. Susceptibility tests performed at each facility demonstrated that 53.7% of H. influenzae isolates and 67.7% of S. pneumoniae isolates in 2003 were drug-resistant. As ampicillin and cephem antibiotics are effective against GBS, E. coli and Listeria at present, then the combination of ampicillin and cephem antibiotics was used as first line antibiotics in many facilities under 4 month of age and a combination of carbapenem which showed effective against PRSP and cephem which showed effective against H. influenzae is first choice against childhood bacterial meningitis over 4 month of age.

Age Distribution↗

Antibiotic susceptibility in relation to penicillin-binding protein genes and serotype distribution of Streptococcus pneumoniae strains responsible for meningitis in Japan, 1999 to 2002.

The antibiotic susceptibilities, genotypes of penicillin (PEN)-binding protein genes (pbp), and serotype distributions of Streptococcus pneumoniae isolates from meningitis patients were investigated by a nationwide surveillance group in Japan between 1999 and 2002. We analyzed 146 isolates from children (</=17 years old) and 73 from adults (>/=18 years old). Isolates with or without abnormal pbp1a, pbp2x, or pbp2b genes identified by PCR were classified into six genotype patterns and 90% MIC (MIC(90)) values for PEN: (i) strains with three normal genes (17.2% of isolates; MIC(90), 0.031 micro g/ml); (ii) strains with abnormal pbp2x (22.1%, 0.063 micro g/ml); (iii) strains with abnormal pbp2b (1.0%, 0.125 micro g/ml); (iv) strains with abnormal pbp2x and pbp2b (7.4%, 0.25 micro g/ml); (v) strains with abnormal pbp1a and pbp2x (12.7%, 0.25 micro g/ml); and (vi) strains with three abnormal PBP genes (39.7%, 4 micro g/ml), which are termed genotypic PEN-resistant S. pneumoniae (gPRSP). Panipenem, a carbapenem, showed an excellent MIC(90) (0.125 micro g/ml) against gPRSP, followed by meropenem and vancomycin (0.5 micro g/ml), cefotaxime and ceftriaxone (1 micro g/ml), and ampicillin (4 micro g/ml). Strains of gPRSP were significantly more prevalent in children (45.2%) than in adults (27.4%). The most frequent serotypes were 6B, 19F, 23F, 6A, and 14 in children and 23F, 22, 3, 10, 6B, and 19F in adults. Serotypes 6B, 6A, 19F, 23F, and 14 predominated among gPRSP. In children, 7- and 11-valent pneumococcal conjugate vaccines would cover 76.2 and 81.3% of isolates, respectively, although coverage would be lower in adults (43.9 and 56.0%, respectively). These findings suggest the need for early introduction of pneumococcal conjugate vaccines and continuous bacteriological surveillance for meningitis.

Adolescent↗

Rapidly increasing prevalence of beta-lactamase-nonproducing, ampicillin-resistant Haemophilus influenzae type b in patients with meningitis.

A total of 395 Haemophilus influenzae strains from 226 Japanese institutions participating in the Nationwide Surveillance Study Group for Bacterial Meningitis were received from 1999 to 2002. All strains were analyzed by PCR to identify the resistance genes, and their susceptibilities to beta-lactam agents were determined. Of these strains, 29.1% were beta-lactamase nonproducing and ampicillin (AMP) susceptible (BLNAS) and lacked all resistance genes; 15.4% were beta-lactamase producing and AMP resistant and had the bla(TEM-1) gene; 30.6% were beta-lactamase nonproducing and AMP resistant (low-BLNAR) and had a Lys-526 or His-517 amino acid substitution in ftsI encoding PBP 3; 13.9% were beta-lactamase nonproducing and AMP resistant (BLNAR) and had an additional substitution of Thr-385 in ftsI; 9.1% were amoxicillin-clavulanic acid resistant (BLPACR I) and had the bla(TEM-1) gene and a Lys-526 or His-517 amino acid substitution in ftsI; and 1.8% showed resistance similar to that of the BLPACR I group (BLPACR II) but had bla(TEM-1) gene and ftsI substitutions, as was the case for the BLNAR strains. All but three strains were serotype b. The prevalence of BLNAR strains has increased rapidly: 0% in 1999, 5.8% in 2000, 14.1% in 2001, and 21.3% in 2002. The MICs at which 90% of BLNAR isolates were inhibited were as follows: AMP, 16 micro g/ml; cefotaxime, 1 micro g/ml; ceftriaxone, 0.25 micro g/ml; and meropenem, 0.5 micro g/ml. All of these values were higher than those for the BLNAS counterpart strains. The relatively wide distributions of the beta-lactam MICs for BLNAR strains presumably reflect variations in ftsI gene mutations. Pulsed-field gel electrophoresis suggested the rapid spread of specific H. influenzae type b strains throughout Japan. Expedited vaccination, rapid identification, and judicious antibiotic use could slow their spread.

Age Factors↗

Ultrastructure of goblet-cell metaplasia from Clara cell in the allergic asthmatic airway inflammation in a mouse model of asthma in vivo.

Mucus overproduction from goblet cells, a characteristic feature of the allergic asthmatic inflammation induced by ovalbumin (OVA) in mice, was examined morphologically. In OVA-untreated (normal) mice, there were no goblet cells in intrapulmonary bronchus and bronchiole. However, goblet cells with or without hyperplasia in the mucosa of inflamed bronchus-bronchiole were recognized in the allergic asthmatic mice. The non-ciliated epithelium containing electron lucent granules (mucus) showed many similarities to Clara cells, which have characteristic secretory granules and many mitochondria, except for the less-developed smooth endoplasmic reticulum seen in normal mice. Ciliated Clara cells with or without mucus were rarely recognized. In addition, mucus was found in neither ciliated nor basal epithelium. The present study suggests that goblet-cell metaplasia in the bronchus and bronchiole of inflamed mucosa may be derived, at least in part, from Clara cells.

Animals↗