Measles virus (MV) is a member of the Morbillivirus genus in the Paramyxoviridae family. Human signaling lymphocyte activation molecule (SLAM) acts as a cellular receptor for MV. SLAM is expressed on immature thymocytes, activated lymphocytes, macrophages and mature dendritic cells. This distribution of SLAM is in accord with lymphotropism and immunosuppressive nature of MV. Canine distemper and rinderpest viruses, other members of the Morbillivirus genus, also use SLAM as receptors. Laboratory-adapted MV strains often use ubiquitously expressed CD46 as an alternative receptor through the amino acid change(s) in the receptor-binding hemagglutinin. Furthermore, MV can infect various cultured cells, albeit with very low efficiency, via SLAM- and CD46-independent pathway, which may also account for MV infection of SLAM^– cells in vivo.

Herpes gladiatorum (HG) plagues the sport of wrestling, especially in high school wrestlers and summer camps they attend. This study evaluated the usage of valacyclovir to prevent acquisition of primary HG, due to herpes simplex virus type 1 (HSV-1), in high school wrestlers at a 28-day wrestling camp. At the beginning and end of camp, IgM and IgG anti-HSV-1 antibodies were collected. Out of 332 male wrestlers, aged 13-20, who entered camp, 94 elected to participate in blood sampling. Sixty-four were on antiviral medication. Among the 94 wrestlers, 28 (29.8%) had positive IgG anti-HSV-1 titers. Of this group, 66 of 94, were HSV-1 IgG seronegative. At the end of camp, 55 of these original seronegative individuals elected to participate in blood sampling and none had detectable IgM anti-HSV-1 and -2 antibodies. Compared to previous years without antiviral usage, introducing prophylactic valacyclovir reduced clinical HG outbreaks by 87% at this 28-day wrestling camp. Due to the high prevalence of this virus in high school wrestlers, serological testing should be done at the beginning of each season. HSV-1 seropositive individuals should consider being on antiviral medication throughout the season to minimize the risk of transmitting the virus to other wrestlers.

We aimed to compare the rate of nasal carriage of Staphylococcus aureus (NCSA) between type 2 diabetic patients and non-diabetic ones and also to reveal the associated risk factors. Type 2 diabetic subjects were selected from outpatient diabetes clinics and control subjects were selected from outpatient internal medicine clinics in the same hospital. The subjects were divided into 3 groups. Group I included 68 subjects on insulin therapy and dietetic treatment, Group II included 80 subjects on oral anti-diabetic agents and dietetic treatment and Group III included 150 age- and sex-matched non-diabetic subjects. The rates of NCSA for Group I, II and III subjects were found to be 24 (35.3%), 11 (13.8%), and 16 (10.7%), respectively. Whereas there was no significant difference in NCSA positivity between Group II and Group III, a significant difference was found between Groups I and III (P < 0.01). Univariate analysis revealed that the following were significant risk factors for NCSA in our diabetic patients: insulin use, hospital admission within the last 6 months, being diabetic for more than 6 years, fasting glucose level above 111 mg/dl and antibiotic usage within the last 6 months. Furthermore, insulin use (odds ratio 3.32) and antibiotic usage within the last 6 months (odds ratio 5.75) were defined as significant risk factors for NCSA in diabetic subjects by the logistic regression method. Our results suggested that the rate of NCSA was significantly higher in type 2 diabetic patients who used insulin or antibiotics within the last 6 months.

Salmonella enterica strains isolated in Okinawa between 1995 and 2005 were analyzed with respect to their serovars and antimicrobial susceptibility, and pulsed-field gel electrophoresis (PFGE) was used to examine their digestion patterns. A total of 1,071 isolates, including 610 from humans, 358 from animal rectal swabs and 103 from meat obtained at grocery stores, were examined. The first 3 most frequent serovars in human isolates were Enteritidis, Weltevreden and Bareilly, together accounting for 65% of the isolates. In isolates from the rectal swabs of laying hens, the predominant serovars were Albany, Saintpaul and Aarhus, accounting for 82% of the isolates. In broilers, 123 of 124 isolates belonged to serovar Infantis, which reflected the high ratio of this serovar in the chicken sold at grocery stores. An antibiogram of human isolates was different from that of broilers and chicken. Chromosomal DNAs of S. Infantis isolated from humans and from the rectal swab of broilers and chickens were examined by PFGE using the restriction enzymes XbaI and BlnI. The digestion patterns of human isolates were not coincident with those of the isolates from the rectal swab of broilers and chicken-meat samples.

The mamushi (Gloydius blomhoffii) snakes that inhabit Japan, Korea, and China produce venoms with similar serological characters to each other. Individual domestic standard mamushi antivenoms have been used for national quality control (potency testing) of mamushi antivenom products in these countries, because of the lack of an international standard material authorized by the World Health Organization. This precludes comparison of the results of product potency testing among countries. We established a regional reference antivenom for these three Asian countries. This collaborative study indicated that the regional reference mamushi antivenom has an anti-lethal titer of 33,000 U/vial and anti-hemorrhagic titer of 36,000 U/vial. This reference can be used routinely for quality control, including national control of mamushi antivenom products.

Hepatitis G virus/GB virus-C (HGV/GBV-C) is a newly identified Flavivirus. Its clinical significance in chronic hepatitis B and C remains controversial. Infection with HGV/GBV-C was surveyed in 500 blood donors, 130 patients with chronic hepatitis B and 173 with hepatitis C, with chronic liver disease, cirrhosis, and/or hepatocellular carcinoma (HCC). HGV/GBV-C RNA was detected by reverse transcription-polymerase chain reaction. An antibody to HGV/GBV-C’s second envelope protein (anti-E2 Ab) was detected using an enzyme immunoassay. The prevalence of HGV/GBV-C RNA was 3.4% and the exposure rate 10.2% in blood donors. The prevalence of HGV/GBV-C RNA in patients with chronic hepatitis B and hepatitis C was 7.7 and 17.3%, respectively (P = 0.002). The prevalence of the HGV/GBV-C infection in hepatitis B carriers increased with the severity of chronic liver disease and risk of HCC. The age and duration of hepatitis B virus infection were the more important contributing factors. Clinical and virological characteristics were comparable between those with and without coinfection of HGV/GBV-C and hepatitis C. The seroconversion rate was high. Coinfection of HGV/GBV-C with hepatitis B or C does not affect disease severity, but accelerates the progression of chronic liver disease and the development of HCC.

In an epidemiological investigation of trench fever in Japan, we compared the seroprevalence of Bartonella quintana in homeless people and in the general population. In homeless rescue outreach programs held in Tokyo from May 2001 to March 2003, 151 blood samples were taken from non-hospitalized homeless people. The prevalence of IgM and IgG antibodies against B. quintana in these people was compared with that in 200 healthy blood donors using a commercially available indirect fluorescent antibody test. Although IgG titers of > or = 1:128 were found in 57% (86/151) of homeless people and 51% (101/200) of blood donors, high titers of > or = to 1:1,024 were encountered only in homeless people (11%, 16/151). Attempts to isolate B. quintana from the blood of homeless people were unsuccessful, but polymerase chain reaction based detection, using Bartonella genus specific primers, demonstrated the presence of B. quintana DNA in the blood of 10 homeless people. Our data suggest that urban trench fever is endemic among the Japanese homeless population.

Recently, the instance of β-lactamase-negative ampicillin (AMP)-resistant (BLNAR) strains of Haemophilus influenzae has exhibited a marked increase in Japan. Our group determined the MICs of 160 clinical isolates of H. influenzae at a university hospital in Okinawa, the southernmost part of Japan, and found that 27 strains were BLNAR, while 24 strains were β-lactamase-producing. Among the latter, 2 strains were resistant to AMP/clavulanic acid. BLNAR strains were shown to be more resistant to cephems than non-BLNAR strains. The competitive affinity assay using biotinylated AMP for penicillin-binding protein (PBP) showed that the binding of cefotiam to PBP 3A/3B of BLNAR strain C2163 was lower than that of the AMP-susceptible strain, while bindings to other PBPs were not changed. The sequences of ftsI, the gene encoding transpeptidase domain of PBP 3A and/or PBP 3B, were determined, and it was found that sequences of the ftsI gene of BLNAR strains were heterogeneous mutations. Deduced amino acid sequence analyses of BLNAR strains showed that three residues (Asn-526, Val-547, and Asn-569) were replaced with Lys, Ile, and Ser, respectively. In addition, some BLNAR strains had an additional three residues (Met-377, Ser-385, and Leu-389) in ftsI replaced with Ile, Thr, and Phe, respectively. Furthermore, changes from Asp-350 to Asn-350 and from Ser-357 to Asn-357 were also found in most BLNAR strains. These substitutions were located around the penicillin binding sites of PBP3. Multiple substitutions in the amino acid sequence seemed to be closely related with extended resistance against β-lactams, including third-generation cephems. Randomly amplified polymorphism DNA fingerprinting of clinical isolates of BLNAR strains showed genetic heterogeneity of the strains, suggesting that the prevalence of BLNAR in this region was a result of the emergence of multiple clones of this phenotype.

The objective of this research was to determine the relationship between YMDD mutations and the genotypes of hepatitis B virus (HBV) during lamivudine treatment. HBV genotypes were determined by nested PCR with 6 pairs of HBV genotype-specific primers (A to F) in serum specimens from 142 hepatitis B patients receiving lamivudine antiviral therapy. YMDD mutations were detected by fluorescent hybridization bioprobe PCR and melting curve assay (FH-PCR-MC). Among 142 serum specimens, 13 samples were genotype B (9.2%), 125 samples were genotype C (88%), 4 samples were genotype D (2.8%), and 80 YMDD mutations were found. The YMDD mutation rates were 69.2 and 54.4% in genotype B and genotype C, respectively. There was no significant difference in the YMDD mutation rate between genotypes B and C. Nine genotype B sera with YMDD mutations were found, including 2 YIDD mutations and 7 YVDD (M + V) mutations. Sixty-eight genotype C sera with YMDD mutations were found, including 34 mutations I (M + I) and 17 mutations V (M + V). There was a significant difference in the YMDD mutation types between genotypes B and C. Our results suggested that the YMDD mutation rate was 56.3% in patients treated with lamivudine for 2 - 4 years. YIDD was the main mutation type. The YMDD mutation rate showed no significant difference between HBV types B and C (P > 0.05), while the YMDD mutation types showed a significant difference between HBV types B and C in Northern China (χ² = 4.6, P < 0.05).

The facultative intracellular bacterium, Francisella tularensis, is an etiological agent of tularemia and is also considered to be a potential biological threat agent due to its extreme infectivity. We established a real-time PCR assay using the LightCycler (LC) system to detect a Francisella-specific sequence of the outer membrane protein (fopA) gene. Twenty-five F. tularensis strains including 16 Japanese isolates were subjected to this LC-PCR assay, and were tested positive, whereas Francisella philomiragia and other bacteria species did not show any specific fluorescent signal. A linear response was observed using F. tularensis genomic DNAs of between 20 fg and 2 ng, corresponding to 1.2 to 1.2×10⁵ bacteria. The newly established real-time PCR allows the detection of the F. tularensis genome specifically, sensitively, and rapidly. This assay may contribute to the standardization of the laboratory diagnosis of tularemia.

Thoracic actinomycosis is a rare disease in children. Diagnosis is typically delayed, since the presentation can be very similar to that of malignant tumors, tuberculosis and fungal infections. We here present the case of a 9-year-old girl who was treated for tuberculosis at the first presentation, for non-Hodgkin’s lymphoma at the second presentation, and for chronic granulomatous disease at the third presentation before actinomycosis was finally diagnosed by culture.

The genomic structure of the iap region in Listeria monocytogenes (serovar 4b), isolated from chicken imported into Japan, was compared with those from Japanese strains. The isolate was similar to the Japanese strains in a comparatively new, rare group. Such strains might be imported from foreign countries.

Ureaplasma urealyticum genital infection may lead to severe clinical implications if left undiagnosed and untreated. The present study was conducted to evaluate the diagnostic efficiency of a polymerase chain reaction (PCR) assay and to determine the prevalence of U. urealyticum in Indian adults with symptoms of genital discharge. Cervical swabs, vaginal swabs and male urethral swabs from 100 patients attending an sexually transmitted disease clinic at a tertiary care hospital in Delhi were screened prospectively for infection with U. urealyticum. The prevalence of U. urealyticum was found to be 32% by culture and 45% by PCR. U. urealyticum was recovered from 8 (47%) and 37 (45%) symptomatic men and women, respectively. The agreement between PCR and culture was 93.75%. PCR improved the test sensitivity by 13% compared to culture. The results confirm the need to use a sensitive and reliable molecular method to prevent the underdiagnosis of ureaplasma infection and to facilitate better clinical management of this infection in India.