Relationships Between Adipokine Profiles, Physique Index, and Severity of Bronchiolitis in Infancy.

INTRODUCTION: Relationships between adipokines, adiposity and severity of acute viral bronchiolitis in infancy have not been elucidated. MATERIALS AND METHODS: We investigated the relationships between three serum adipokines (leptin, adiponectin and TNF-α), physique index (Kaup index) and clinical severity in 13 bronchiolitis infants. Seven healthy infants were enrolled as the control group. We used Modified Pulmonary Index Score (MPIS) to evaluate bronchiolitis severity. RESULTS: No significant differences in adipokine levels were found between groups. In bronchiolitis infants, Kaup index negatively correlated with MPIS (r = -0.614, p = 0.03). A positive correlation was observed between the serum leptin/adiponectin ratio and MPIS (r = 0.618, p = 0.03), although correlations were not observed between respective serum adipokines levels and MPIS. Serum leptin and adiponectin had significantly negative correlations with age (r = 0.815, p = 0.001 and r = 0.566, p = 0.04, respectively), but not Kaup index. CONCLUSION: The severity of viral bronchiolitis in infancy may be related to the adipokine profile, but not adiposity.

Clinical and virological characteristics of rotavirus gastroenteritis and prevalence of strains in Tochigi, Japan.

AIM: Rotavirus infection is a serious gastrointestinal infection that is usually prevalent during winter months and often seen in infants and young children. Studies on genotypes of prevalent rotavirus strains are important for preventing infection, developing vaccines, and its evaluation. The purpose of this study was to make an investigation of a rotavirus infection in the Nasu Region of Tochigi, Japan and to compare findings to those of other regions. MATERIALS AND METHODS: We examined the clinical findings in 147 patients who attended the Department of Pediatrics at International University of Health and Welfare Hospital in the Nasu-shiobara City, Tochigi Prefecture, Japan during April 1, 2008 to March 31, 2010. RESULTS: We analyzed the clinical findings of 37 patients with a fecal sample positive for rotavirus antigen. Furthermore, viral genotypes were determined using rotavirus-positive samples from 27 of these 37 patients. The genotypes were determined as G1P [8] in 5 samples, G3P [8] in 5 samples, G9P [8] in 3 samples, and G6P [9] in 2 samples. We were able to analyze the phylogenetic trees of these genotypes. CONCLUSION: Of particular note, we detected G6P [9] which were extremely rare in humans but common in cattle. Studies on changes in prevalent strains after vaccine introduction need to be conducted.

Detection and full genomic analysis of G6P[9] human rotavirus in Japan.

A rare genotype G6P[9] was identified in two human group A rotavirus strains designated as KF14 and KF17, that were detected in stool specimens from children with diarrhea in Japan. VP7 gene sequences of these two strains were identical and genetically closely related to G6 human rotavirus strains reported in European countries and the United States. To our knowledge, this is the first report of detection of a G6 human rotavirus in Japan. For further genetic analysis to elucidate the origin of the G6 rotavirus, nearly full-length sequences of all 11 RNA segments were determined for the KF17 strain. The complete genomic constellation of KF17 was determined as G6-P[9]-I2-R2-C2-M2-A3-N2-T3-E3-H3, a novel genotype constellation for human rotavirus. Phylogenetic analysis indicated that VP6, VP1-3, and NSP2 genes of KF17 clustered with bovine-like G6 human strains and some animal strains into sub-lineages distinct from those of common DS-1-like G2 human rotaviruses. On the other hand, KF17 genes encoding VP4, NSP1, and NSP3-5 showed high sequence identities to the human G3P[9] strain AU-1, and clustered with AU-1 and some feline strains within the same lineage. These findings suggested that the G6P[9] human rotavirus detected in Japan may have occurred through reassortment among uncommon bovine-like human rotaviruses and human/feline AU-1-like rotaviruses.

Development of rapid diagnostic reagents for measles.

Measles diagnosis has thus far been based on clinical symptoms in daily clinical practice. However, atypical cases are not uncommon; a simple and rapid method of measles diagnosis is clinically required. Lateral flow-based rapid diagnosis reagents are widely used for point-of-care testing in Japanese clinics, because it does not require special skills and facilities. We have developed a rapid diagnostic reagent for measles that employs the lateral flow method. The lower limit of detection of this reagent was almost the same for recombinant proteins of wild-type and vaccine strain, at 5.1 x 10(3) copies/test. This lower limit of detection and the specificity of this reagent suggest its efficacy for the diagnosis of measles infection.

Assay of Chlamydia pneumoniae-specific IgM antibodies by ELISA method--reduction of non-specific reaction and resetting of serological criteria by measuring IgM antibodies--.

In the present study, we tried to reduce the non-specific reactions for measuring anti-Chlamydia pneumoniae IgM antibodies by the ELISA kit of HITAZYME C. pneumoniae Ab-IgM (HITAZYME IgM) by using a new absorbent. We also tried to reset the IgM cut-off index (ID) of HITAZYME IgM by testing serum samples from healthy children and healthy adults with no respiratory symptoms. The results suggest that the use of the new absorbent (anti-human IgG antibodies) may reduce the non-specific reactions by rheumatoid factor and anti-nuclear antibodies, and that the setting of the higher cut-off ID (2.00), calculated as the mean ID+3SD of the serum samples from healthy children and healthy adults, respectively, would improve the specificity of IgM during the measurement by HITAZYME IgM.

Rapid detection of human immunodeficiency virus type 1 group M by a reverse transcription-loop-mediated isothermal amplification assay.

A rapid one-step reverse transcription-loop-mediated isothermal amplification (RT-LAMP) assay targeting the pol-integrase gene was developed to detect human immunodeficiency virus type 1 (HIV-1) group M. This HIV-1 RT-LAMP assay is simple and rapid, and amplification can be completed within 35min under isothermal conditions at 60 degrees C. The 100% detection limit of HIV-1 RT-LAMP was determined using a standard strain (WHO HIV-1 [97/656]) in octuplicate and found to be 120 copies/ml. The RT-LAMP assay was evaluated for use for clinical diagnosis using plasma samples collected from 57 HIV-1-infected and 40 uninfected individuals in Cameroon, where highly divergent HIV-1 strains are prevalent. Of the 57 samples from infected individuals, 56 harbored group-M HIV-1 strains, such as subtypes A, B, G, F2, and circulating recombinant forms (CRFs) _01, _02, _09, _11, _13; all were RT-LAMP positive. One sample harboring group-O HIV-1 and the 40 HIV-1-uninfected samples were RT-LAMP negative. These findings indicate that HIV-1 RT-LAMP can detect HIV-1 group-M RNA from plasma samples rapidly and with high sensitivity and specificity. These data also suggest that this RT-LAMP assay can be useful for confirming HIV diagnosis, particularly in resource-limited settings.

[Safety and efficacy in two-dose vaccination using measles and rubella combined (MR) vaccine].

Measles and rubella combined (MR) vaccine and two-dose-vaccination have been used in Japan since 2006. only children undergoing monovalent measles and rubella vaccination undergo a second vaccination. We intend to administer MR vaccine twice to Japanese children from 2011, so studied the safety and efficacy of two-dose MR vaccination. Subjects were 75 pre school children undergoing MR vaccine manufactured by Biken at one year old in a clinical trial. Children were observed for adverse events for 28 days after the second MR vaccination. Efficacy was determined by measuring antibodies for measles and rubella before and after (six to eight weeks later) the second vaccination. Results showed that fever frequency decreased significantly from 27.3% to 14.9% (p < 0.05), and eruption decreased from 12.2% to 6.8% from the first to the second vaccination, whereas, the frequency of redness and swelling at the inoculation site increased from 7.3% to 10.8% and 2.9% to 8.1%. Differences are not statistically significant. Measles antibody titer determined by NT assay and rubella antibody titer measured by HI assay increased significantly from prevaccination to postvaccination (p < 0.0001). Measles antibodies measured by NT and EIA assays and rubella antibody measured by HI assay turned positive in all subjects after the second MR vaccination. In conclusion, two-dose MR vaccination should be safe and effective in eliminating measles and rubella in Japan.

HIV-2 amino acid substitutions in Gag and Env proteins occurring simultaneously with viral load upsurge in a drug-naïve patient.

It has been reported that the peptides of human immunodeficiency virus type 2 (HIV-2) most frequently recognized by cytotoxic T lymphocytes are firstly in Gag and secondly in Env proteins. In the present case study, we attempted to observe amino acid substitutions in Gag and Env proteins and related parameters possibly associated with an increase in HIV-2 load. A sudden, eightfold, increase in HIV-2 load occurred in a drug-naïve patient with human leukocyte antigen-B*5801 during the last phase of a longitudinal observation period from months 29 to 40. The genetic diversity of Gag and Env increased gradually prior to the HIV-2 load increase. The proportions of synonymous substitutions in both Gag and Env were greater than the proportions of nonsynonymous substitutions at every sampling point for 40 months, and the net charge of the V3-loop increased from months 29 to 40. Three amino acid substitutions (V2861 in Gag, K303T and N337 K/R in Env) were observed from months 29 to 40. Only one amino acid substitution (V286I) was observed with an increase in HIV-2 load in the Gag region where the clustering of epitopes was reported. These results suggest that the sites encompassing these three substituted positions are candidates for HIV-2 epitopes, although further careful examinations will be required.

A case of meningoencephalitis associated with G1P[8] rotavirus infection in a Japanese child.

We report the case of a 2-y, 11-month-old boy with G1P[8] rotavirus infection accompanied by acute meningoencephalitis. Substitutions in both the VP4 and VP7 genes were found in the identified strain. A commonly circulating G1P[8] rotavirus with such mutations might be associated with the pathogenesis of CNS complications, including meningoencephalitis.

Current problems of measles control in Japan and Western Pacific Region.

Measles is still the leading cause of childhood death and is a vaccine-preventable disease globally. Even countries in which measles had been eradicated still remain at risk of importation from countries that have not yet eliminated the disease. Although two dose of immunization program with combined measles and rubella (MR) vaccine has been started since April 2006, there are still estimated 5-10 thousands measles cases annually in Japan. We introduced the Vero/hSLAM cell line for routine isolation of wild measles viruses in the WHO laboratory network. Vero/hSLAM cells express both CD46 and SLAM receptors and are highly sensitive to both vaccine and wild measles virus strains. Although Vero/hSLAM cell lines require an expensive antibiotics (G418) to maintain the transfection necessary for expression of the human SLAM receptor, we are trying to establish more simple, rapid and reliable diagnostic assays for measles virus infection.

Emergence of antiretroviral therapy resistance-associated primary mutations among drug-naive HIV-1-infected individuals in rural western Cameroon.

The prevalence of antiretroviral therapy (ART) resistance-associated mutations among HIV-1 strains in western Cameroon was evaluated by genotypically analyzing strains isolated from drug-naive individuals. Proviral DNA was extracted from 54 blood samples and amplified by polymerase chain reaction of protease, reverse transcriptase, integrase, and envelope genes. At least 4 clones per sample were analyzed. Of 54 HIV-1 strains, 45 (83.3%) had a concordant subtype or circulating recombinant form (CRF) designation: 40 CRF02_AG, 2 subtype A1, 2 G, and 1 F2. The remaining 9 (16.7%) had a discordant subtype: 6 subtype A1/CRF02_AG, 2 D/CRF02, and 1 G/CRF02. Protease inhibitor-associated primary resistance mutations were found in 4 (7.4%) cases: M46L with full clones in 1 case, and M46I, M46L, and V82A as minor populations in 1 case each. Reverse transcriptase inhibitor-associated primary resistance mutations were found in 5 (9.8%) samples: Y188C in 2 cases, and L100I, M184V, and V75I in 1 case each, although all of these mutations were found as minor populations. This is one of the first reports of the emergence of primary ART resistance mutations among drug-naive, non-B subtype HIV-1-infected individuals in Cameroon. Follow-up studies should be conducted to assess whether these drug-resistant mutants found as minor populations might impact future ART.

Screening for vaginal shedding of cytomegalovirus in healthy pregnant women using real-time PCR: correlation of CMV in the vagina and adverse outcome of pregnancy.

The impact of cytomegalovirus (CMV) infection of the genital tract during pregnancy on adverse pregnancy outcomes is not understood fully. A real-time PCR assay was used to determine vaginal shedding of CMV in 993 healthy pregnant Japanese women and the results were compared with the outcome of pregnancy. CMV DNA was detected in 76 (7.7%) of the women. The outcome of pregnancy could be determined finally in 848 women, of whom 60 (7.1%) were CMV positive. The carriers of CMV had an increased miscarriage rate (RR 6.96, 95% CI 2.04-23.84, P < 0.01). These findings suggest that latent genital tract CMV infection predisposes to adverse pregnancy outcomes.

Human cytomegalovirus genetic variability in strains isolated from Japanese children during 1983-2003.

The genetic variability of 74 human cytomegalovirus (HCMV) clinical isolates from 60 Japanese infants and children during 1983-2003 was investigated, and the relevance to their clinical course was studied. The patients consisted of 10 asymptomatic congenitally infected babies, 45 infected perinatally or postnatally resulting in HCMV mononucleosis/hepatitis and 5 immunocompromised hosts. The hypervariable region of the HCMV genome, that is the a sequence and UL144 region was analyzed using the polymerase chain reaction (PCR) and unrooted phylogenetic trees. HCMV glycoprotein B (gB) polymorphism was also studied. Unrooted phylogenetic trees of a sequence and UL144 allowed the isolates to be grouped to 5 and 3 clades, respectively. Three gB genotypes were also determined. However, there was no correlation between specific genotypes of these three genes and clinical forms, except for congenital infection which fell into one of three clades of the UL144 gene. In addition, the variability of the three genes had no correlation with each other. This implies that study of a single gene is insufficient for investigating the molecular epidemiology of HCMV. This study provides basic data on the genetic variability of HCMV in an Asian population and should help to determine the strains for vaccine candidates.

Chronological changes of incidence and prognosis of children with asymptomatic congenital cytomegalovirus infection in Sapporo, Japan.

BACKGROUND: Chronological changes of the incidence of congenital cytomegalovirus (CMV) infection and the longitudinal prognosis in children with asymptomatic congenital infection were investigated. METHODS: Congenital CMV infection, as demonstrated by isolation of the virus within the first week of life, was diagnosed in infants born in Sapporo, Japan, during the 26-year period between 1977 and 2002. RESULTS: Congenital infection was diagnosed in 37 (0.31%) of 11,938 infants. Thirty-two infants were (86.5%) asymptomatic and 5 (13.5%) were symptomatic at birth. CONCLUSIONS: Although a decrease in the total incidence of congenital CMV infection has been seen in recent years, screening of congenital infection at birth seems to be necessary to detect late-onset neurodevelopmental sequelae.

Etiological agents of lower respiratory tract infections in Japanese children.

To investigate the etiology of pediatric community-acquired pneumonia and bronchitis, we conducted a prospective, population-based study covering the total population < 15 years of age in 16 municipalities in Hokkaido, Japan, during the period of April 2000 to March 2001. Chest radiographs were available for all cases (n = 921; 398 as pneumonia and 523 as bronchitis) and paired sera for serologic assays were available for more than half of the cases. The following specimens were also collected: nasopharyngeal swabs for viral, bacteriological, mycoplasmal and chlamydial studies, blood for serology and blood culture. The children were then followed-up on days 3, 7 and 14. Specific infecting organisms were identified in a total of 853 (92.6%) out of 921 patients (398 cases of pneumonia and 523 cases of bronchitis) including 205 with mixed infection as follows: Mycoplasma pneumoniae, 252 (274%) patients; respiratory syncytial (RS) virus, 188 (20.4%); influenza A virus, 110 (11.9%); Streptococcus pneumoniae, 95 (10.3%); Haemophilus influenzae, 90 (9.8%); Haemophilus parainfluenzae, 35 (3.8%); Staphylococcus aureus, 29 (3.1%); adenovirus, 27 (2.9%); Moraxella catarrhalis, 12 (1.3%); Pseudomonas aeruginosa , 7 (0.8%); Chlamydia pneumoniae, 6 (0.7%); and other agents, 2 (0.2%). Mycoplasma infections were seen even in patients less than 5 years and RS and influenza A virus infections in patients more than 5 years of age. The importance of M. pneumoniae and RS virus in the etiology of lower respiratory infections in Japanese children was confirmed.

Current problems of perinatal Chlamydia trachomatis infections.

Chlamydia trachomatis has been recognized as a pathogen of trachoma, nongonococcal urethritis, salpingitis, endocervicitis, pelvic inflammatory disease, inclusion conjunctivitis of neonates, follicular conjunctivitis of adults, infantile pneumonia and associated conditions. Chlamydial infections during pregnancy may also cause a variety of perinatal complications. Different antigenic strains of C. trachomatis from endocervical, nasopharyngeal and conjunctival origins have been associated with different clinical conditions. Control programs emphasizing early diagnosis, targeted screening, and effective treatment will lead to an eventual decline in the incidence of perinatal chlamydial infection. This review focuses on current problems of perinatal C. trachomatis infections in the aspects of microbiological and immunological pathogenesis.

Mycoplasma pneumoniae infection and its genotypical characterization in children of Hokkaido, Japan.

To investigate the etiology of Mycoplasma pneumoniae infections we conducted a prospective study covering the total pediatric population in Hokkaido, Japan. Paired sera for serologic assays were available for more than half of the cases (n = 921; 398 as pneumonia and 523 as bronchitis). The nasopharyngeal swabs were also collected for isolation and PCR study. The types of P1 gene from clinical isolates of M. pneumoniae obtained from two different areas of Hokkaido, Sapporo and Kushiro, were determined by PCR-RFLP assay. M. pneumoniae was identified in 174 (43.7%) out of 398 patients with pneumonia and was identified in 78 (14.9%) out of 523 (86.2%) patients with bronchitis. P1 genes of 14 clinical isolates of M. pneumoniae were classified into 13 group II and 1 group I. Two clinical isolates were unclassified by PCR-RFLP assay. Mycoplasma infections were seen even in patients less than 5 years of age. Generation of antigenic variation by DNA recombination may occur in clinical isolates.

Human cytomegalovirus infection during pregnancy and detection of specific T cells by intracellular cytokine staining.

OBJECTIVE: The flow cytometric assay was evaluated as a tool for real-time monitoring of human cytomegalovirus (HCMV)-specific cellular immunity in pregnant women. METHODS: We screened for HCMV infection in pregnant women in Sapporo, Japan, during the year 2000, by serologic assays, virus isolation from urine, and PCR to detect DNA in cervical swabs. The frequencies of HCMV-specific CD4+ T cells in pregnant women with serum anti-HCMV IgG antibody were detected by intracellular cytokine (ICC), interferon-gamma (IFN-gamma) and tumor necrosis factor-alpha (TNF-alpha) staining. RESULTS: The levels of intracellular cytokines in pregnant women with serum anti-HCMV IgG antibody were significantly higher than those in women without anti-HCMV IgG antibody (P = 0.011 for IFN-gamma and P = 0.023 for TNF-alpha) but lower than those in non-pregnant women with serum anti-HCMV IgG antibody. Frequencies of HCMV-specific CD4+ T cells were higher in infants with symptomatic congenital infection than in infants with asymptomatic perinatal infection. CONCLUSIONS: This ICC assay may reflect immunologic activity against HCMV infection in pregnant women with immunosuppressive conditions.