Two polyomaviruses, BK virus (BKV) and JC virus (JCV), are ubiquitous in the human population, generally infecting children asymptomatically and then persisting in renal tissue. It is generally thought that reactivation leads to productive infection for both viruses, with progeny shed in the urine. Several studies have shown that the rate of JC viruria increases with the age of the host, but a systematic approach to examine the shedding of BKV has not been developed. To elucidate the relationship between BK viruria and host age, we obtained urine from donors (healthy volunteers or nonimmunocompromised patients) who were divided into nine age groups, each containing 50 members. A high-sensitivity PCR was used to detect BKV and JCV DNA from urinary samples, and the specificity of amplification was confirmed by sequencing or restriction analysis of the amplified fragments. The rate of BK viruria was relatively low in subjects aged <30 years but gradually increased with age in subjects aged >30 years. However, BK viruria was less frequent than JC viruria in adults. The detected BKV isolates were classified into subtypes, and detection rates for individual subtypes were compared among age groups; this analysis showed that viruria of subtypes I (the most prevalent subtype) and IV (the second most prevalent subtype) occurred more frequently in older subjects. Therefore, our results reveal new aspects of BK viruria in nonimmunocompromised individuals.Humans are infected with two polyomaviruses, JC virus (JCV) and BK virus (BKV), and serological surveys have shown that both viruses are ubiquitous in the human population, generally infecting children asymptomatically (18) and then persisting in renal tissue (4, 7). Both viruses are usually nonpathogenic for nonimmunocompromised individuals, but they cause clinically significant diseases in immunocompromised patients. Thus, BKV causes BKV-associated nephropathy in organ transplant patients (e.g., renal transplant patients) (8), while JCV causes progressive multifocal leukoencephalopathy, typically in patients infected with human immunodeficiency virus (2).Renal JCV and BKV in nonimmunocompromised individuals are not latent but replicate frequently, excreting progeny viruses in urine. The incidence of JC viruria is known to increase with age and reaches nearly 70% at 80 to 89 years old (12, 13); in contrast, the shedding of BKV has not been studied systematically (15), although it is likely that BK viruria is also age dependent. To establish the relationship between BK viruria and host age, we collected urine samples from nonimmunocompromised individuals (healthy volunteers and general patients, all of whom were Japanese). The urine donors were divided into nine groups based on age (0 to 9, 10 to 19, 20 to 29, 30 to 39, 40 to 49, 50 to 59, 60 to 69, 70 to 79, and 80 to 89 years old), with each group having 50 members. A high-sensitivity PCR was used to detect BKV DNA from urinary samples, and the specificity of amplification was confirmed by sequencing of the amplified frag...

In Fischer rats infected with Japanese encephalitis virus (JEV) at 13 days after birth and sacrificed 12 weeks later, the major pathological changes resembled those found in Parkinson's disease. Specifically there was neuronal loss with gliosis which was confined mainly to the zona compacta of the substantia nigra, with a notable absence of lesions in the cerebral cortex and cerebellum. Changes were bilateral being most severe in the central part of the zona compacta. Immunohistochemical studies with anti-tyrosine hydroxylase (TH) demonstrated that the number of TH-positive neurons was significantly decreased in the substantia nigra compared to controls, while comparable numbers of TH-positive neurons were found in the basal ganglia in both JEVtreated rats and age-matched controls. JEV-infected rats showed marked bradykinesia, with significant behavioral improvement being observed following administration of L-DOPA. Immunohistochemical studies failed to detect JEV antigens in any region of the rat brain and the JEV genome was undetectable in the substantia nigra and the cerebral cortex using the reverse transcription-polymerase chain reaction (RT ± PCR). The findings suggest that JEV infection of rats under the conditions described may serve as a model of virus induced Parkinson's Disease.

We established small interfering RNA (siRNA) directed against poly(ADP-ribose) polymerase 1 (PARP-1) that effectively reduces the expression of PARP-1 in two human cell lines. Established siRNA against PARP-1 significantly suppressed human immunodeficiency virus type 1 (HIV-1) replication, as well as the activation of the integrated HIV-1 long terminal repeat promoter. These results indicate that PARP-1 is required for efficient HIV-1 replication in human cells. We propose that PARP-1 may serve as a cellular target for RNA interference-mediated gene silencing to inhibit HIV-1 replication.

This report concerns a carrier cell culture (designated JCI) infected persistently with JC virus (JCV). Immunostaining with an anti-JCV antiserum revealed that JCI was a carrier culture in which only a small fraction of the cells (approximately 1.5%) produced the virus. The JCV titre was increased strikingly by incubating confluent JCI cells for 4-6 days in medium containing a low concentration of fetal bovine serum (2%). Viral genomes cloned from the persistently infected JCI cells were heterogeneous with respect to size, but most clones had an alteration of the same regulatory region (designated CR-JCI). Transfection experiments with a chimeric JCV DNA (Mad-1/CR-JCI), in which the regulatory region was CR-JCI and the other region was derived from an infectious JCV (Mad-1) DNA, showed that CR-JCI was less efficient in inducing viral growth than the regulatory regions of IMR-32-adapted JCVs. The transfected cells could be readily subcultured, and they continued to produce JCV. It is concluded that a decrease in the activity of the JCV regulatory region is of importance for the maintenance of the carrier state of JCI cells.

An immunochromatography (IC) kit for human adenovirus (HAdV) was evaluated with 138 patient nasopharyngeal samples. The samples were collected at a sentinel clinic in Japan from January through June 2003. Patients were diagnosed by clinical manifestation of pharyngoconjunctival fever (n ‫؍‬ 38) or exudative tonsillitis (n ‫؍‬ 100). The IC kit was positive for 84% (116 of 138) of patients diagnosed at bedside. The remaining extract solution of the IC kit test was transferred into maintenance medium and tested via laboratory diagnoses. The IC kit had 95% sensitivity (116 of 122 patients) with HAdV isolation (isolation) as the standard and 91% sensitivity (116 of 128 patients) with PCR as the standard. All of the IC kit-positive samples were isolation and PCR positive. Similarly, all the isolation-positive samples were PCR positive. Twenty-two IC kit-negative samples were evaluated by real-time PCR. Six samples were IC kit negative and isolation positive and contained 3.8 ؋ 10 7 to 2.5 ؋ 10 9 copies of the HAdV genome/ml. Five samples that were only PCR positive contained 3.0 ؋ 10 4 to 3.8 ؋ 10 5 copies of the HAdV genome/ml, but one sample was real-time PCR negative. We conclude that the IC kit is a useful bedside diagnostic tool for HAdV infections because it has 95% sensitivity (compared to isolation), but a negative result does not always rule out HAdV infection.