Distribution pattern of entry holes of the tree-killing bark beetle Polygraphus proximus.

Bark beetles attack their hosts at uniform intervals to avoid intraspecific competition in the phloem. Bark texture and phloem thickness also affect bark beetle attacks, and the bark characteristics are not spatially homogeneous; therefore, the distribution patterns of entry holes can demonstrate an aggregated distribution. Polygraphus proximus Blandford (Coleoptera: Scolytinae) is a non-aggressive phloephagous bark beetle that feeds on Far Eastern firs. They have caused mass mortality in Russia and Japan. However, the distribution pattern of entry holes of P. proximus and spatial relationships with bark characteristics have not been studied. Thus, we investigated the distribution pattern of entry holes of P. proximus. The distribution of entry holes was significantly uniform in most cases. As the attack density increased, an aggregated distribution pattern within a short distance (< 4.0 cm) was observed. The rough bark had a significantly higher number of entry holes than the remaining bark. The distribution pattern of entry holes demonstrated a significantly aggregated spatial association with rough bark. Finally, rough bark around knots had significantly thicker phloem than the remaining barks. These suggest that P. proximus may preferentially attack rough bark to reproduce in the thicker phloem under a rough bark surface.

Minimal biofilm eradication concentration of antimicrobial agents against nontypeable Haemophilus influenzae isolated from middle ear fluids of intractable acute otitis media.

Nontypeable Haemophilus influenzae (NTHi) makes the clinical course of acute otitis media (AOM) intractable by forming a biofilm that may hamper the clearance of the bacteria from middle ear cavity. In this study, we evaluated the minimum biofilm eradication concentration (MBEC) of antimicrobial agents against biofilm-forming NTHi strains. Twelve NTHi strains isolated from middle ear fluids of Japanese children with intractable AOM before antimicrobial treatment were evaluated for MBEC of fluoroquinolones in comparison with those of ß-lactams and macrolides. AMPC and CDTR required much higher concentration, i.e., high MBECs, to suppress the biofilm formation of NTHi. In contrast, fluoroquinolones followed by macrolides showed lower MBECs. MBEC would be a good parameter to infer the efficacies of antimicrobials against NTHi in biofilm.

PspA family distribution, antimicrobial resistance and serotype of Streptococcus pneumoniae isolated from upper respiratory tract infections in Japan.

BACKGROUND: The protection against pneumococcal infections provided by currently available pneumococcal polysaccharide conjugate vaccines are restricted to the limited number of the serotypes included in the vaccine. In the present study, we evaluated the distribution of the pneumococcal capsular type and surface protein A (PspA) family of pneumococcal isolates from upper respiratory tract infections in Japan. METHODS: A total of 251 S. pneumoniae isolates from patients seeking treatment for upper respiratory tract infections were characterized for PspA family, antibiotic resistance and capsular type. RESULTS: Among the 251 pneumococci studied, the majority (49.4%) was identified as belonging to PspA family 2, while most of the remaining isolates (44.6%) belonged to family 1. There were no significant differences between the distributions of PspA1 versus PspA2 isolates based on the age or gender of the patient, source of the isolates or the isolates' susceptibilities to penicillin G. In contrast, the frequency of the mefA gene presence and of serotypes 15B and 19F were statistically more common among PspA2 strains. CONCLUSION: The vast majority of pneumococci isolated from the middle ear fluids, nasal discharges/sinus aspirates or pharyngeal secretions represented PspA families 1 and 2. Capsular serotypes were generally not exclusively associated with certain PspA families, although some capsular types showed a much higher proportion of either PspA1 or PspA2. A PspA-containing vaccine would potentially provide high coverage against pneumococcal infectious diseases because it would be cross-protective versus invasive disease with the majority of pneumococci infecting children and adults.

Evaluation of a rapid immunochromatographic ODK-0901 test for detection of pneumococcal antigen in middle ear fluids and nasopharyngeal secretions.

Since the incidence of penicillin-resistant Streptococcus pneumoniae has been increasing at an astonishing rate throughout the world, the need for accurate and rapid identification of pneumococci has become increasingly important to determine the appropriate antimicrobial treatment. We have evaluated an immunochromatographic test (ODK-0901) that detects pneumococcal antigens using 264 middle ear fluids (MEFs) and 268 nasopharyngeal secretions (NPSs). A sample was defined to contain S. pneumoniae when optochin and bile sensitive alpha hemolytic streptococcal colonies were isolated by culture. The sensitivity and specificity of the ODK-0901 test were 81.4% and 80.5%, respectively, for MEFs from patients with acute otitis media (AOM). In addition, the sensitivity and specificity were 75.2% and 88.8%, respectively, for NPSs from patients with acute rhinosinusitis. The ODK-0901 test may provide a rapid and highly sensitive evaluation of the presence of S. pneumoniae and thus may be a promising method of identifying pneumococci in MEFs and NPSs.

Haemophilus influenzae and Haemophilus haemolyticus in tonsillar cultures of adults with acute pharyngotonsillitis.

OBJECTIVE: The aim of this study was to evaluate the clinical implication of Haemophilus haemolyticus, one of the closest relative of Haemophilus influenzae, on acute pharyngotonsillitis. METHODS: We applied polymerase chain reaction (PCR) for 16S ribosomal DNA (rDNA) and IgA protease gene (iga) to distinguish H. haemolyticus and H. influenzae. RESULTS: Among the 199 Haemophilus spp. isolated from 214 patients with acute pharyngotonsillitis, 52 (24.3%) H. influenzae strains and 23 (10.7%) H. haemolyticus strains were identified by polymerase chain reaction (PCR) for 16S rDNA and IgA protease gene (iga). All H. haemolyticus strains showed hemolysis on horse blood agar and there were no other Haemophilus spp., nonhemolytic H. haemolyticus and H. influenzae variant strains that had absent iga gene. H. hemolyticus showed close genetic relationship with H. influenzae evaluated by pulsed field gel electrophoresis (PFGE). The cases of acute pharyngotonsillitis showing WBC=7000/mm(3) or CRP=8 mg/dl were frequently found among cases with H. influenzae rather than cases with H. haemolyticus. CONCLUSION: H. haemolyticus is a pharyngeal commensal that is isolated frequently from adults with acute pharyngotonsillitis.

Nontypeable Haemophilus influenzae isolated from intractable acute otitis media internalized into cultured human epithelial cells.

OBJECTIVES: The aim of this study is to examine the internalization of nontypeable Haemophilus influenzae (NTHi) into human epithelial cells. METHODS: Bactericidal assay was applied to examine the effects of antibiotics against cell-adherent NTHi using HEp-2 cells. A trans-well chamber assay was applied to examine the internalization and penetration of NTHi using Detroit562 cells. RESULTS: The adherence of NTHi to HEp-2 cells was noted after 2h of incubation. Azithromycin had a strong bactericidal effect against both cell-associated and non-adherent NTHi, while ceftriaxone did not show bactericidal effects on NTHi adhered to the HEp-2 cells. Three (60.0%) out of five NTHi isolates from the nasopharynx of children with intractable acute otitis media (AOM) internalized into and subsequently penetrated through the epithelial cells at various degrees. Azithromycin had a strong bactericidal effect against the cell-internalized NTHi, while ceftriaxone was bactericidal only against extracellular NTHi. CONCLUSION: The potential of NTHi as the intracellular pathogen may contribute to the persistent existence of this pathogen that result in the prolonged and intractable clinical course of AOM. Azithromycin may be a therapeutically significant antibiotic for patients with prolonged respiratory tract infections due to NTHi.

Distribution of fibronectin-binding protein genes (prtF1 and prtF2) and streptococcal pyrogenic exotoxin genes (spe) among Streptococcus pyogenes in Japan.

Two hundred and seventy-two strains of Streptococcus pyogenes isolated from patients with invasive and noninvasive infections in Japan were evaluated for the prevalence of fibronectin-binding protein genes (prtF1 and prtF2). The possible associations of the genes with streptococcal pyrogenic exotoxin genes, macrolide resistance genes, and emm types were also evaluated. Overall, about 50% of S. pyogenes isolates carried fibronectin-binding protein genes. The prevalence of the prtF1 gene was significantly higher among isolates from noninvasive infections (71.4%) than among isolates from invasive infections (30.8%; P = 0.0037). Strains possessing both the prtF1 and prtF2 genes were more likely to be isolates from noninvasive infections than isolates from invasive infections (50.6% vs 15.4%; P = 0.019). S. pyogenes isolates with streptococcus pyrogenic exotoxin genes (speA and speZ) were more common among isolates without fibronectin-binding protein genes. The speC gene was more frequently identified among isolates with fibronectin-binding protein genes (P = 0.05). Strains belonging to emm75 or emm12 types more frequently harbored macrolide resistance genes than other emm types (P = 0.0094 and P = 0.043, respectively). Strains carrying more than one repeat at the RD2 region of the prtF1 gene and the FBRD region of the prtF2 gene were more prevalent among strains with macrolide resistance genes than among strains negative for macrolide resistance genes. These genes (i.e., the prtF1, prtF2, and spe genes) may enable host-bacteria interaction, and internalization in the host cell, but may not enable infection complications such as invasive diseases.

Dopamine D1-like receptor antagonist, SCH23390, exhibits a preventive effect on diabetes mellitus that occurs naturally in NOD mice.

Dopamine receptors have five isoforms, termed D1-D5. The D1 and D5 receptors form the D1-like group that couples with the Galphas class of G proteins, while D2, D3 and D4 form the D2-like group that couples with the Galphai class of G proteins. In our previous studies, a D1-like-R antagonist, SCH23390, inhibited DC-mediated Th17 differentiation and exhibited preventive and therapeutic effects on experimental autoimmune encephalomyelitis (EAE) in mice. We herein demonstrate in the current study that in the pancreas obtained from NOD mice, islet infiltrates appear to be composed of mononuclear cells positive for IL-23R, one of the specific markers for Th17. Thereafter, NOD mice were orally administered SCH23390 from week 6 to week 26. At week 26, 67% and 25% of mice developed diabetes in the control and the SCH23390 groups, respectively (p<0.05). A histological examination of SCH23390-treated mice exhibited a typical normal islet structure with no signs of periductal and perivascular infiltrates, whereas the islets from vehicle controls showed insulitis. In week 26, spleen cells were re-stimulated with anti-CD3 and anti-CD28 antibodies in vitro and exhibited an augmentation of IFNgamma induction and the suppression of IL-17 induction in the SCH23390-treated mice. These findings indicate that antagonizing D1-like-R suppresses IL-17 expression, thereby leading to a decreased occurrence of NOD.

Inhibitory effects of pasuchaca (Geranium dielsiaum) extract on alpha-glucosidase in mouse.

The methanolic extract of pasuchaca (Geranium dielsiaum) (PsEx) was found to suppress blood glucose elevation after oral administration of sucrose, maltose, and starch, but not after oral administration of glucose, in the mouse. In vitro examination of the inhibitory effect of PsEx on maltase activity revealed that PsEx strongly inhibited mouse small intestine maltase activity. Taken together, these results suggest that the inhibitory effect of PsEx on alpha-glucosidase activity might contribute to delay in carbohydrate digestion and subsequent lowering of the blood glucose level, thereby leading to prevention and cure of diabetes.

Absence of pretreatment markers that predict the emergence of YMDD mutants during lamivudine treatment--the results of a prospective multi-center study.

BACKGROUND/AIMS: The emergence of YMDD mutants in patients who are treated with lamivudine may determine the clinical prognosis. However, currently there are no clinical or virological factors that predict specifically the emergence of the mutants. METHODOLOGY: To define these factors, we analyzed 69 patients with chronic hepatitis B infection who were treated with lamivudine (LAM) and followed prospectively for at least 12 months. RESULTS: Of the 69 patients, 12 (17.4%) developed YMDD mutants up to 12 months after the start of LAM. The incidence of YMDD mutants was slightly higher in those who were younger, had higher HBV DNA titers, lower ALT levels, genotype C, and mutations in the core promoter before treatment. However, we could not find any significant factors that correlated with the appearance of the mutants. CONCLUSIONS: Currently, using conventional virological assays, it is difficult to predict the development of mutants before LAM treatment. Management of flare-ups of hepatitis, due to the appearance of mutants, should always be envisaged when LAM treatment is started.

Klebsiella pneumoniae liver abscess associated with septic spinal epidural abscess.

A 56-year-old Japanese man with hypertension presented with a 10 days history of high fever, right and left upper quadrant tenderness. An abdominal ultrasonography and computerized tomographic scan revealed a large collection in the right lobe of the liver that was consistent with an abscess. A drainage catheter was placed and purulent fluid was drained. Cultures of the fluid and blood were positive for a strain of ampicillin-resistant Klebsiella pneumoniae. Six days after admission, paraplegia and urinary retention were found. On the neurological examination, deep tendon reflexes of the lower extremities were absent bilaterally. Magnetic resonance imaging scan detected thoracic spinal epidural abscess and paraspinal abscess. He received the emergent decompressive laminectomy. Culture of surgical specimen grew ampicillin-resistant K. pneumoniae. The patient was treated with biapenem intravenously. Thereafter, clinical symptoms improved gradually and he was removed to the professional hospital to continue rehabilitation for gait disturbance on hospital day 147.

Genotyping of Streptococcus pneumoniae and Haemophilus influenzae isolated from paired middle ear fluid and nasopharynx by pulsed-field gel electrophoresis.

Twenty-eight isolates of Streptococcus pneumoniae and 30 isolates of Haemophilus influenzae from paired nasopharynx and middle ear fluids of 21 children with acute otitis media (AOM) were evaluated to determine genotypes by polymerase chain reaction and pulsed-field gel electrophoresis (PFGE). Among the 28 isolates of S. pneumonaie, 21 isolates (75.0%) possessed mutations in the pbp1a,pbp2x, and pbp2b genes, and 7 isolates (25%) had mutations in the pbp2x gene. Nineteen isolates (67.9%) expressed the mefE gene, and 5 isolates (17.9%) possessed the ermB gene. Among the 30 isolates of H. influenzae, 5 isolates (16.7%) had mutations in pbp3 genes, 3 isolates (10.0%) produced beta-lactamase, and 2 (6.7%) isolates possessed mutations both in the pbp3 gene and the beta-lactamase gene. Ten out of the 14 pairs (71.4%) of the restriction fragment patterns of S. pneumoniae from paired nasopharynx and middle ear fluids were indistinguishable following PFGE analysis. The same patterns were identified among 5 children of unrelated families. The restriction fragment patterns of H. influenzae isolated by PFGE were also indistinguishable in 13 out of the 15 pairs (86.7%) of nasopharynx and middle ear fluids. The genetic similarity between nasopharyngeal and middle ear isolates suggests that the causative bacteria migrate from the nasopharynx into the middle ear cavity via the Eustachian tube. Some resistant strains might be prevalent. In children with AOM, the nasopharynx could have been colonized by a virulent strain of bacteria that replaced the benign, commensal bacteria and then progressed to the middle ear, where they caused AOM.

[Roles of beta-catenin overexpression and adenomatous polyposis coli mutation in head and neck cancer].

Beta-catenin is an undercoat protein of cadherin, a cellular adhesion molecule. Beta-catenin also functions as a transcriptional activator downstream of the Wnt signaling pathway. Intracellular beta-catenin is regulated by the formation of a complex with APC (adenomatous polyposis coli) protein. The activation of this pathway by stabilization with beta-catenin has been shown to be an important step in the development of colorectal carcinoma, which is mainly caused by inactivating mutations in the APC tumor suppressor gene or by activating mutations in exon 3 of the beta-catenin gene. This study was conducted to clarify the contribution of beta-catenin accumulation and the mutation of the beta-catenin gene to the carcinogenesis of head and neck cancer. Beta-catenin accumulation was examined immunohistochemically in 49 frozen or formalin-fixed, paraffin-embedded samples of head and neck tumors. We also performed a direct sequence analysis of APC and beta-catenin to examine the cause of beta-catenin accumulation. Genomic DNA was extracted and purified from fresh tissue samples of head and neck cancers. We examined the APC mutation cluster region in 15 samples and analyzed beta-catenin exon 3 mutations in 31 cases. Twelve out of 49 (24.5%) cases exhibited beta-catenin accumulation in our histochemical study. The 5 year survival rate was 0% in the beta-catenin accumulation group, compared to 50% in the non-accumulation group, (p < 0.01). This finding strongly suggests that beta-catenin may play an important role in the carcinogenesis or progression of head and neck cancer. One of the 15 cases exhibited an APC missense mutation that led to the replacement of amino acids; this case died in 12 months. Regarding the beta-catein mutation, non of the 31 samples exhibited a gene mutation in beta-catenin exon 3. Thus, the rate of APC and beta-catenin mutation in head and neck cancer may be very low.