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W J Bellini

Publications and source records attributed to W J Bellini.

At least 19 recordsLinked to original sources
PubMed2004

Subacute sclerosing panencephalitis in the differential diagnosis of encephalitis.

The authors describe five cases of subacute sclerosing panencephalitis (SSPE) identified through the California Encephalitis Project that emphasize the importance of considering SSPE in the differential diagnosis of encephalitis, particularly among pediatric patients. SSPE was not suspected in the differential diagnosis of three of the cases until results of measles testing were known. The diagnosis of SSPE is often not considered by clinicians because of its rarity in the United States and the nonspecific clinical manifestations at onset.

Adolescent↗
PubMed2004

Negative impact of clinical misdiagnosis of measles on health workers' confidence in measles vaccine.

We conducted a survey to determine the accuracy of the clinical diagnosis of measles in Zimbabwe. Between December 1996 and February 1997, we collected blood samples and clinical and demographic information from a sample of 105 children with a clinical diagnosis of measles. A clinical case of measles was defined as a person with a history of fever, rash for three or more days, and either cough, coryza, or conjunctivitis. A laboratory-confirmed case of measles or rubella had IgM antibodies against measles virus or rubella virus respectively. A total of 91% of children met the clinical case definition. Among those who met the clinical case definition for measles, 72% were IgM-positive for measles virus only, 23% were IgM-positive for rubella virus only, 3% were IgM-positive for both measles and rubella viruses, and 2% were IgM-negative for both viruses. This study demonstrates the importance of considering selective laboratory confirmation of measles in periods of high disease incidence when the effectiveness of the vaccine is questioned.

Adolescent↗
PubMed2001

Induction of cytokine mRNA in peripheral blood mononuclear cells of infants after the first dose of measles vaccine.

To better characterize the cytokine response to measles virus vaccine, we examined the levels of IL-2, IL-4, IL-5, IL-10, IL-12 and gamma-interferon (gamma-IFN) in measles virus-stimulated peripheral blood mononuclear cells from 18 donors before and 2 weeks after vaccination. Donors were grouped as seropositive or seronegative on the basis of measles-specific IgM antibody present at 2 weeks postvaccination. After vaccination, similar levels of upregulation of IL-2 and gamma-IFN mRNA were observed in the two groups. The majority of donors in both groups did not exhibit an increase in measles specific IL-4 or IL-10 mRNA after vaccination. IL-12 mRNA was not induced by measles virus in any of the donors. A statistically significant upregulation of IL-5 mRNA was observed among seropositive (9/13) compared with seronegative (1/5) donors after vaccination (P=0.09, one tailed Fisher's test). The observed measles specific induction of IL-5 mRNA is suggestive of a possible association between IL-5 production and an antibody response to measles virus.

Antibodies, Viral↗
PubMed2001

Molecular characterization of the polymerase gene and genomic termini of Nipah virus.

In 1998, Nipah virus (NV) emerged in peninsular Malaysia, causing fatal encephalitis in humans and a respiratory disease in swine. NV is most closely related to Hendra virus (HV), a paramyxovirus that was identified in Australia in 1994, and it has been proposed that HV and NV represent a new genus within the family Paramyxoviridae. This report describes the analysis of the sequences of the polymerase gene (L) and genomic termini of NV as well as a comparison of the full-length, genomic sequences of HV and NV. The L gene of NV is predicted to be 2244 amino acids in size and contains the six domains found within the L proteins of all nonsegmented, negative-stranded (NNS) RNA viruses. However, the GDNQ motif found in most NNS RNA viruses was replaced by GDNE in both NV and HV. The 3' and 5' termini of the NV genome are nearly identical to the genomic termini of HV and share sequence homology with the genomic termini of other members of the subfamily Paramyxovirinae. At 18,246 nucleotides, the genome of NV is 12 nucleotides longer than the genome of HV and they have the largest genomes within the family Paramyxoviridae. The comparison of the structures of the genomes of HV and NV is now complete and this information will help to establish the taxonomic position of these novel viruses within the family Paramyxoviridae.

Amino Acid Sequence↗
PubMed2001

Genomic characterization of wild-type measles viruses that circulated in different states in Brazil during the 1997 measles epidemic.

Despite the marked reduction in the incidence of measles in Brazil, a measles epidemic occurred in this country in 1997. The measles cases observed during this epidemic began to reappear in large numbers in São Paulo, and spread to Rio de Janeiro and other Brazilian states. In the present study molecular biology techniques were used for the detection and genomic characterization of measles viruses from clinical samples such as urine and nasopharyngeal secretions collected in the states of Rio de Janeiro, Minas Gerais and Paraná, during the 1997 epidemic. RT-PCR and nucleotide sequence analysis of part of the carboxyl-terminal region of the nucleoprotein gene of measles viruses obtained directly from clinical samples or from infected cell cultures during this epidemic classified all as wild-type of genotype D6. As the genotype D6 was identified in different Brazilian states, this study demonstrated that this genotype was circulating in Brazil during the 1997 epidemic.

Adult↗
PubMed2001

Comparative detection of measles and rubella IgM and IgG derived from filter paper blood and serum samples.

We compared the use of serum and filter paper blood spots as specimen sources for the detection of measles- and rubella-specific IgM and IgG. We collected capillary blood into microtainer tubes and onto filter paper spots from 60 children and 60 healthy adults. The blood was collected from 12-15-month-old children approximately 3 weeks after primary vaccination with measles, mumps, rubella vaccine, and the sample-pairs were tested for measles-specific IgM and IgG antibodies by using a capture antibody EIA and an indirect EIA, respectively. We tested sample-pairs from a subset of participants for rubella- specific IgM and IgG antibodies by using commercially available capture IgM (Captia) and indirect IgG (Wampole) assays. The concordance of results from serum and filter paper blood spots was high for all assays: 98% for measles IgM, 93% for measles IgG, 94% for rubella IgM, and 93% for rubella IgG, and increased to between 96-100% for all four assays when indeterminate samples were excluded. The correlation coefficients for EIA signals were 0.99 and 0.77 for measles IgM and IgG, respectively, and 0.92 and 0.94 for rubella IgM and IgG, respectively. The cut-off values used for filter paper samples were the same as those used for serum samples for all tests except for the rubella IgM assay. The use of filter paper blood spots is a promising future option for the detection of measles- and rubella-specific antibodies.

Adult↗
PubMed2001

Genetic characterization of contemporary wild-type measles viruses from Vietnam and the People's Republic of China: identification of two genotypes within clade H.

Genetic characterization was conducted on 17 wild-type measles viruses isolated near Hanoi, Vietnam, during 1998 as well as on eight viruses isolated in the Hunan, Hainan, Shandong, and Anhui provinces of the People's Republic of China during 1995, 1998, and 1999. Previous studies had shown that, compared to wild-type measles viruses found in other parts of the world, wild-type viruses from China were genetically distinct and comprised a new clade of viruses, clade H. In this study, sequence analyses of the nucleotides coding for the COOH terminal 150 amino acids of the nucleoprotein (N) and the entire hemagglutinin (H) protein indicated that although all of the viruses from Vietnam were members of clade H, they were clearly distinct from the Chinese viruses. With the exception of MVi/Beijing.China/94/1, the Vietnamese viruses differed from all of the Chinese viruses by at least 3.5 and 2.5% at the nucleotide level for the N and H genes, respectively. These data suggest that clade H should be divided into two genotypes with the Chinese viruses placed in genotype H1 and the Vietnamese viruses in genotype H2. Sequence analysis of measles viruses imported into the United States from either China or Vietnam demonstrated that this designation of genotypes will be helpful in future measles surveillance activities.

China↗
PubMed2001

Molecular biology of Hendra and Nipah viruses.

The structure and genetic organization of Hendra and Nipah viruses places them in the subfamily Paramyxovirinae. However, low homology with other subfamily members and several novel biological and molecular features such as genome length and F(0 )cleavage site suggest classification in a new genus within the Paramyxovirinae.

Amino Acid Sequence↗
PubMed2000

Molecular characterization of Nipah virus, a newly emergent paramyxovirus.

Recently, a new paramyxovirus, now known as Nipah virus (NV), emerged in Malaysia and Singapore, causing fatal encephalitis in humans and a respiratory syndrome in pigs. Initial studies had indicated that NV is antigenically and genetically related to Hendra virus (HV). We generated the sequences of the N, P/C/V, M, F, and G genes of NV and compared these sequences with those of HV and other members of the family Paramyxoviridae. The intergenic regions of NV were identical to those of HV, and the gene start and stop sequences of NV were nearly identical to those of HV. The open reading frames (ORFs) for the V and C proteins within the P gene were found in NV, but the ORF encoding a potential short basic protein found in the P gene of HV was not conserved in NV. The N, P, C, V, M, F, and G ORFs in NV have nucleotide homologies ranging from 88% to 70% and predicted amino acid homologies ranging from 92% to 67% in comparison with HV. The predicted fusion cleavage sequence of the F protein of NV had a single amino acid substitution (K to R) in comparison with HV. Phylogenetic analysis demonstrated that although HV and NV are closely related, they are clearly distinct from any of the established genera within the Paramyxoviridae and should be considered a new genus.

Amino Acid Sequence↗
PubMed2000

Nipah virus: a recently emergent deadly paramyxovirus.

A paramyxovirus virus termed Nipah virus has been identified as the etiologic agent of an outbreak of severe encephalitis in people with close contact exposure to pigs in Malaysia and Singapore. The outbreak was first noted in late September 1998 and by mid-June 1999, more than 265 encephalitis cases, including 105 deaths, had been reported in Malaysia, and 11 cases of encephalitis or respiratory illness with one death had been reported in Singapore. Electron microscopic, serologic, and genetic studies indicate that this virus belongs to the family Paramyxoviridae and is most closely related to the recently discovered Hendra virus. We suggest that these two viruses are representative of a new genus within the family Paramyxoviridae. Like Hendra virus, Nipah virus is unusual among the paramyxoviruses in its ability to infect and cause potentially fatal disease in a number of host species, including humans.

Animals↗
PubMed2000

Clinical isolates of measles virus use CD46 as a cellular receptor.

Laboratory strains of measles viruses (MV), such as Edmonston and Halle, use the complement regulatory protein CD46 as a cell surface receptor. The receptor usage of clinical isolates of MV, however, remains unclear. Receptor usage by primary patient isolates of MV was compared to isolates that had been passaged on a variety of tissue culture cell lines. All of the isolates could infect cells in a CD46-dependent manner, but their tropism was restricted according to cell type (e.g., lymphocytes versus fibroblasts). The results indicate that patient isolates that have not been adapted to tissue culture cell lines use CD46 as a receptor. In addition, passaging primary MV patient isolates in B95-8 cells selected variants that had alternate receptor usage compared to the original isolate. Thus, changes in receptor usage by MV are dependent upon the cell type used for isolation. Furthermore, our results confirm the relevance of the CD46 receptor to natural measles infection.

Animals↗
PubMed2000

Measles eradication: is it in our future?

Measles eradication would avert the current annual 1 million deaths and save the $1.5 billion in treatment and prevention costs due to measles in perpetuity. The authors evaluate the biological feasibility of eradicating measles according to 4 criteria: (1) the role of humans in maintaining transmission, (2) the availability of accurate diagnostic tests, (3) the existence of effective vaccines, and (4) the need to demonstrate elimination of measles from a large geographic area. Recent successes in interrupting measles transmission in the United States, most other countries in the Western Hemisphere, and selected countries in other regions provide evidence for the feasibility of global eradication. Potential impediments to eradication include (1) lack of political will in some industrialized countries, (2) transmission among adults, (3) increasing urbanization and population density, (4) the HIV epidemic, (5) waning immunity and the possibility of transmission from subclinical cases, and (6) risk of unsafe injections. Despite these challenges, a compelling case can be made in favor of measles eradication, and the authors believe that it is in our future. The question is when.

Adult↗
PubMed1999

Induction of intercellular adhesion molecule 1 gene expression by measles virus in human umbilical vein endothelial cells.

The expression of intercellular adhesion molecule 1 (ICAM-1) by endothelial cells is important for the regulation of adhesion and transendothelial migration of a variety of leukocytes that express the integrins lymphocyte function-associated antigen 1 (LFA-1) and/or Mac-1. Here, we demonstrate strain-specific differences in the ability of measles virus (MV) to induce ICAM-1 expression. The vaccine strain Moraten (Mor) rapidly induced high levels of ICAM-1 mRNA and protein expression, whereas the vaccine strain CAM-70 and the Edmonston wild type (Ed-wt) strain were far less effective, even when they were used at very high multiplicities of infection (MOIs). Strain-specific differences in the induction were not a consequence of differences in the ability to infect ECs. Furthermore, induction of ICAM-1 by Mor was not dependent on de novo expression of MV or cellular proteins. Dual-immunofluorescence analysis indicated that there was no association between the expression of either MV nucleocapsid or hemagglutinin protein and the induction of ICAM-1 expression. Some human umbilical vein endothelial cells (HUVECs) that expressed high nucleocapsid protein in response to either Mor or CAM-70 failed to express elevated ICAM-1, whereas some HUVECs that were incubated with Mor expressed high ICAM-1 prior to expression of MV nucleocapsid protein. Strain-specific differences in the ability of Mor and CAM-70 to induce ICAM-1 correlated with their ability to activate the latent transcription factor NF-kappaB. These studies suggest a preexisting component of MV particles that leads to strain-specific differences in the activation of NF-kappaB and the induction of ICAM-1 gene expression.

Animals↗
PubMed1999

The effect of timing of sample collection on the detection of measles-specific IgM in serum and oral fluid samples after primary measles vaccination.

This study compares the timing of the rise and decline of measles-specific IgM in serum samples and in oral fluid samples. Two hundred and eighty 9-month-old infants presenting for routine measles vaccination in Addis Ababa, Ethiopia, were enrolled. Paired serum and oral fluid samples were collected before and 1, 2, 3 or 4 weeks after measles vaccination. Samples were tested by using a modified antibody-capture enzyme immunoassay. For the 321 IgM-negative pre- and post-vaccination serum samples, 317 (99 %) of their corresponding oral fluid samples were IgM-negative. Among the 130 IgM-positive serum samples, 75% of their paired oral fluid samples were IgM-positive, with the percentage rising to 87% after oral fluid samples collected > or =3.5 weeks after vaccination were excluded. Among the post-vaccination serum samples, the percent IgM-positive peaked in week 3 and declined to 79% in week 4. For post-vaccination oral fluid samples, the percent IgM-positive peaked in weeks 2 and 3, and then declined to 43% in week 4. This modified antibody-capture enzyme immunoassay appears to detect vaccine-induced measles-specific IgM in the first 3 weeks after vaccination.

Female↗
PubMed1999

Measles virus infection in rhesus macaques: altered immune responses and comparison of the virulence of six different virus strains.

Measles remains a major cause of childhood mortality, with questions about virus virulence and pathogenesis still requiring answers. Rhesus macaques were infected with 5 different culture-adapted strains of measles virus, including 2 from patients with progressive vaccine-induced disease, and a sixth nonculture-adapted strain, Bilthoven. All caused infection detectable by reverse transcriptase-polymerase chain reaction and induction of antibody. Chicago-1 and Bilthoven induced viremias detectable by leukocyte cocultivation. Bilthoven induced Koplik's spots, conjunctivitis, and rash. Lymphopenia and depressed interleukin (IL)-2 production were followed by monocytosis and eosinophilia. All monkeys, including 41 involved in a primate facility outbreak, showed suppressed responses to phytohemagglutinin. As the rash resolved production of IL-2, IL-1beta, tumor necrosis factor-alpha, IL-6, and IL-5 mRNA increased. Monkeys are useful for studies of measles immunopathogenesis, but virus strains must be carefully chosen. Increased virulence of vaccine strains isolated from immunocompromised infants with fatal infections was not evident.

Animals↗
PubMed1999

Measles inclusion-body encephalitis caused by the vaccine strain of measles virus.

We report a case of measles inclusion-body encephalitis (MIBE) occurring in an apparently healthy 21-month-old boy 8.5 months after measles-mumps-rubella vaccination. He had no prior evidence of immune deficiency and no history of measles exposure or clinical disease. During hospitalization, a primary immunodeficiency characterized by a profoundly depressed CD8 cell count and dysgammaglobulinemia was demonstrated. A brain biopsy revealed histopathologic features consistent with MIBE, and measles antigens were detected by immunohistochemical staining. Electron microscopy revealed inclusions characteristic of paramyxovirus nucleocapsids within neurons, oligodendroglia, and astrocytes. The presence of measles virus in the brain tissue was confirmed by reverse transcription polymerase chain reaction. The nucleotide sequence in the nucleoprotein and fusion gene regions was identical to that of the Moraten and Schwarz vaccine strains; the fusion gene differed from known genotype A wild-type viruses.

Encephalitis, Viral↗
PubMed1999

Comparison of L proteins of vaccine and wild-type measles viruses.

The nucleotide sequences of the large (L) genes of ten measles virus (MV) strains were determined. These strains included the Moraten and Rubeovax vaccine strains and their Edmonston wild-type (wt) progenitor, two additional vaccine strains and five genotypically divergent wt isolates. The nucleotide and predicted amino acid sequences were compared with six previously sequenced L genes and the number and location of variable amino acid positions were characterized. The recent wt isolates demonstrated the greatest amount of variability found to date in the highly conserved L protein. Three full-length wt L proteins were expressed in mammalian cells and their ability to form a complex with the MV phosphoprotein was demonstrated. While no set of amino acid substitutions associated consistently with wt or vaccine strains was identified, these data will provide a basis for the analysis of the activity of L proteins from vaccine and wt viruses in a functional assay.

Amino Acid Sequence↗