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Studies have shown that pneumococcal vaccination reduces the incidence of Streptococcus pneumoniae infections but does not change the prevalence of S. pneumoniae nasopharyngeal colonization. To comprehensively and longitudinally assess the epidemiology of S. pneumoniae after the introduction of pneumococcal vaccination, we monitored the prevalence and antimicrobial susceptibility of S. pneumoniae, irrespective of its serotypes or pathogenicity, by analyzing specimens collected from a large number of patients at Jikei University Hospitals from 2009 to 2017. A total of 5763 S. pneumoniae isolates were identified out of 375,435 specimens from various sources of patients in different age groups. The prevalence of S. pneumoniae isolated only from patients5 years old was significantly reduced with the widespread use of pneumococcal vaccines, although this reduction differed by areas where patients resided. The incidence of pneumococcal infections, including bacteremia and otitis media, clearly decreased among patients5 years old after the introduction of pneumococcal vaccination, while the prevalence of S. pneumoniae isolated from blood specimens of patients 15-64 years old increased, suggesting the involvement of non-vaccine serotypes in the incidence of invasive pneumococcal infections. The antimicrobial susceptibility of S. pneumoniae improved after the introduction of pneumococcal vaccination. Our results show that pneumococcal vaccination has a suppressive effect on the prevalence of S. pneumoniae and the incidence of pneumococcal infections, at least for children5 years old, in association with an improvement in the antimicrobial susceptibility of S. pneumoniae. However, further measures will be needed to control invasive pneumococcal infections caused by non-vaccine serotypes.

Exhaled gas analysis is a non-invasive test ideal for continuous monitoring of biological metabolic information. We analyzed the exhaled gas of patients with inflammatory diseases for trace gas components that could serve as biomarkers that enable early detection of inflammatory diseases and assessment of treatment efficacy. Furthermore, we examined the clinical potential of this method. We enrolled 34 patients with inflammatory disease (male/female = 14/20, aged 20–89 years) and 69 healthy participants as controls (male/female ratio = 49/20 aged 30–70 years). Volatile components from exhaled gas were collected and analyzed by a gas chromatography-mass spectrometry system, and the data were examined for gender differences, age, correlation with inflammatory markers (white blood cell count, C-reactive protein, erythrocyte sedimentation rate), and changes in markers before and after treatment. The data was tested for statistical significance through discriminant analysis by Volcano plot, Analysis of variance test, principal component analysis, and cluster analysis comparing healthy and patient groups. There were no significant differences in the trace components of exhaled gas by gender or age. However, we found difference in some components of the exhaled gas between healthy and untreated patients. In addition, after treatment, gas patterns including the patient-specific components changed to a state closer to the inflammation-free status. We identified trace components in the exhaled gas of patients with inflammatory diseases and found that some of these regressed after treatment.

Research has previously shown that ultraviolet light C (UV-C) can inactivate unexpected infection. However, this type of potential disinfection is dramatically reduced for the shadow area such as under desk or medical equipment. Because the UV-C reflectance ratio is low on the general wall surfaces. We compared Stucco against the other materials to investigate whether we could improve disinfection for the shadow area. The reflectance ratios of UV-C irradiation of each material were examined, with particular attention to the rates for the author’s Modified Stucco. To evaluate the disinfection effects of the UV-C reflective lighting, colonies of E. coli and of Staphylococcus hominis were cultured in an agar media and counted over a certain time period after applying UV-C irradiation from a sterilizing lamp onto the investigation materials. The author’s Modified Stucco, produced reflectance ratios that was 11 times that of white wallpaper. This demonstrated that the UV-C reflected on the Stucco wall having optimum components and their compositions inhibited the number of E. coli and S. hominis, resulting in significantly disinfection effects on white wallpapers. The space with Modified Stucco and then irradiated by a UV-C may give a strong disinfection effect.

Haemophilus influenzae and Streptococcus pneumoniae are often the cause of serious diseases such as meningitis. We designed a nested PCR assay to identify these pathogens from cerebrospinal fluid samples. The first-step PCR was able to detect eubacterial rRNA genes with a unified set of universal primers. In the second-step PCR, the identification primers, HI I and II and SP I and II, could detect H. influenzae and S. pneumoniae respectively through amplification of the rRNA spacer between the 16S and 23S rRNA genes. We suggest that the two-step PCR assay can be used as a novel method for the immediate and retrospective diagnosis of bacterial meningitis caused by H. influenzae and S. pneumoniae.

Chimeric oligonucleotides consisting of 21 bases of ribonucleic acid (RNA) with six bases of deoxyribonucleic acid (DNA) at the 3′-hydroxyl terminus (chimeric RNA–DNA primer) and the recombinant thermostable DNA polymerase derived from Thermus thermophilus (rTth DNA polymerase) were utilized to efficiently amplify DNA fragments using the conventional polymerase chain reaction (PCR). The reaction required the use of both DNA polymerase and reverse transcriptase during each thermal cycle to form a double-stranded DNA in which one terminus was an RNA : DNA hybrid. Due to the ability of rTth DNA polymerase to function as both the DNA polymerase and reverse transcriptase, a chimeric RNA–DNA primer was shown to serve as a primer in the conventional PCR procedure. We further demonstrate the advantages of using these PCR products to identify microorganisms using surface plasmon resonance (SPR) technology. This detection system was able to distinguish Shiga toxin-producing Escherichia coli O157 : H7 strains from other bacteria such as Salmonella typhimurium and S. enteritidis.

Panton-Valentine leukocidin (PVL) secreted by Staphylococcus aureus is known to cause severe skin, soft tissue and lung infections. To assess the prevalence and genetic characteristics of PVL-positive S. aureus in our hospital, we investigated 86 S. aureus isolates isolated from skin and soft tissue pus between September 2011 and May 2012 at Daisan Hospital, the Jikei University School of Medicine (Tokyo, Japan). All isolates were investigated for the mecA gene and PVL gene by PCR amplification. The MRSA isolates confirmed were genotyped using SCCmec typing. PVL-gene positive isolates confirmed by the PVL-RPLA (reverse passive latex agglutination) assay were characterized by agr typing and multilocus sequence typing (MLST). Overall 6 (3 MSSA isolates and 3 MRSA isolates) PVL-positive strains (7.0%) were detected. The PVL prevalence was 11.1% in MRSA and 5.1% in MSSA. PVL-positive strains were isolated from young adults (range: 8-47 years) outpatient. Patients infected with PVL-positive MRSA were significantly younger than those infected with PVL-negative MRSA(32 and 68 years, respectively; P = 0.009, t-test). The 6 PVL positive strains were assigned by the MLST to 6 STs that were prevalent among PVL-positive strains. The SCCmec type of the PVL-positive MRSA were classified into 2 types (type IV or V) that were generally characteristic of CA-MRSA. Our data are consistent with some previous reports showing that PVL gene is found in certain ST strains. The PVL-positive strain must be taken into account when S. aureus is isolated from young adult SSTI.

Streptococcus pneumoniae is one of the important human pathogens in clinical microbiology. A polymerase chain reaction assay was designed to detect and identify S. pneumoniae through amplification of the ribosomal DNA spacer regions between the pneumococcal 16S-23S ribosomal RNA genes. Thirty-two Streptococcus and non-Streptococcus strains were tested to verify the specificity of the assay, and only S. pneumoniae strains gave a positive reaction. This method is a powerful technique for the rapid identification of S. pneumoniae.

Three patients who were carriers of hepatitis B virus (HBV) and had hematologic malignancies, experienced fulminant hepatic failure after withdrawal of chemotherapy. Before treatment, each patient had inactive HBV infection with undetectable viral DNA polymerase; two patients were negative for hepatitis B e antigen. After chemotherapy, DNA polymerase increased and HBV variants with mutations in the precore region prevailed in their sera. These results implicate precore mutants thriving after chemotherapy and restored immune responses of patients in the pathogenesis of severe hepatic failure.

We describe two cases of fungal granulomatous interstitial nephritis (GIN) presenting as acute kidney injury (AKI). Increased serum creatinine was detected in Patient 1 after chemotherapy for pharyngeal cancer and in Patient 2 after steroid pulse therapy for bronchial asthma. Renal histology of both patients revealed GIN. Polymerase chain reaction (PCR)-based detection of fungal DNA sequences from kidney tissue demonstrated Trichosporon laibachii and Candida albicans, respectively. When AKI occurs in an immunocompromised host, differential diagnosis of fungal interstitial nephritis should be considered. Furthermore, PCR-based detection of fungal DNA sequences from renal specimens can be useful for rapid diagnosis.

The aims of this study were to assess the long-term efficacy of lamivudine (LAM) plus adefovir dipivoxil (ADV) combination therapy in patients with chronic hepatitis B resistant to LAM, to identify predictive factors of complete viral response (HBV-DNA

There are cases of hepatitis involving occult hepatitis B virus (HBV) infection in which, even though the HB surface antigen (HBsAg) is negative, HBV-DNA is detected by a polymerase chain reaction (PCR). We conducted a sequence analysis of the entire HBV region in a case of non-B non-C chronic hepatitis in a 46-year-old female. A diagnosis of non-B non-C chronic hepatitis was made. Although HBV markers, such as HBs antibody (anti-HBs), anti-HBc, HBeAg and anti-HBe, were negative, HBV-DNA was positive. Nested PCR was performed to amplify the precore region of HBV-DNA and all remaining regions by long nested PCR. Sequence analysis of the two obtained bands was conducted by direct sequencing. Compared with the control strains, the ATG (Methionine) start codon in the X region had mutated to GTG (Valine). It is assumed that a mutation at the start codon in the X region may be the reason why HBV markers are negative in some cases of hepatitis that involve occult HBV infection.

We designed a polymerase chain reaction (PCR) assay for rapid detection of prokaryotic 16S-23S spacer regions. This PCR assay consisted of nested DNA amplifications. The first-step PCR was able to detect the general presence of eubacteriales with a unified set of universal primers. The universal primers were selected from highly conserved regions in 16S and 23S ribosomal RNA (rRNA) genes and amplified DNAs from all 62 different species of bacteria tested. In the second-step PCR, the identification primers could detect four important bacterial species through amplification of the rRNA spacer regions between the 16S-23S rRNA genes. For Staphylococcus aureus, intraspecies variation in spacer amplification products was observed with S. aureus specific primers. We suggest that the nested PCR assay could be used as a novel method for the identification and typing in epidemiological studies of S. aureus.

We attempted the rapid detection method of Legionella pneumophila by the asymmetric PCR and the fluorescence polarization. Eleven extracted DNAs from L. pneumophila serogroup 1 to approximately 6, L. bozemanii, L. dumoffii, L. gormanii, L. micdadei, and Pseudomonas aeruginosa were amplified by asymmetric PCR, and the polarization of those products were measured. Only the polarization of L. pneumophila serogroup 1 to approximately 6 rose within a few minutes after the beginning of measurement. The sensitivity to L. pneumophila using this method was 10(3) cells.