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1.
Astrobiology ; 22(S1): S238-S241, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-34904891

RESUMEN

The National Aeronautics and Space Administration-European Space Agency (NASA-ESA) Mars Sample Return (MSR) campaign involves the collection of samples on Mars by the Perseverance (Mars 2020) rover and their return to Earth. To accomplish this, the Orbiting Sample container (OS) will be sent to Mars to accommodate the collected samples then launched from Mars and returned to Earth, where the samples will be removed for examination in the Sample Return Facility (SRF). Crucial to this entire sequence will be establishment of the required level of cleanliness inside the OS. In February 2021, the NASA Headquarters' Mars Sample Return Program and Office of Planetary Protection assembled an MSR OS Tiger Team (OSTT) to discuss the appropriate cleanliness level options of the interior of the OS. The team's remit was primarily focused on evaluating the trade-offs between Planetary Protection cleanliness levels 4a and 4b. These cleanliness levels are determined by the Committee on Space Research (COSPAR) planetary protection regulations, where 4a requires <300 bacterial spores/m2 and <3 x 105 bacterial spores on the spacecraft (in this case, the interior of the OS) and 4b mandates the more stringent requirement of <30 bacterial spores on the spacecraft. This report documents the consensus opinion submitted by the OSTT that recommended the interior of the OS be cleaned to a 4a requirement with any feasible added effort toward 4b. This report provides, as well, the rationale for that decision.


Asunto(s)
Marte , Vuelo Espacial , Medio Ambiente Extraterrestre , Planetas , Nave Espacial , Estados Unidos , United States National Aeronautics and Space Administration
2.
MMWR Morb Mortal Wkly Rep ; 65(21): 543-6, 2016 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-27254248

RESUMEN

Zika virus is a single-stranded RNA virus in the genus Flavivirus and is closely related to dengue, West Nile, Japanese encephalitis, and yellow fever viruses (1,2). Among flaviviruses, Zika and dengue virus share similar symptoms of infection, transmission cycles, and geographic distribution. Diagnostic testing for Zika virus infection can be accomplished using both molecular and serologic methods. For persons with suspected Zika virus disease, a positive real-time reverse transcription-polymerase chain reaction (rRT-PCR) result confirms Zika virus infection, but a negative rRT-PCR result does not exclude infection (3-7). In these cases, immunoglobulin (Ig) M and neutralizing antibody testing can identify additional recent Zika virus infections (6,7). However, Zika virus antibody test results can be difficult to interpret because of cross-reactivity with other flaviviruses, which can preclude identification of the specific infecting virus, especially when the person previously was infected with or vaccinated against a related flavivirus (8). This is important because the results of Zika and dengue virus testing will guide clinical management. Pregnant women with laboratory evidence of Zika virus infection should be evaluated and managed for possible adverse pregnancy outcomes and be reported to the U.S. Zika Pregnancy Registry or the Puerto Rico Zika Active Pregnancy Surveillance System for clinical follow-up (9,10). All patients with clinically suspected dengue should have proper management to reduce the risk for hemorrhage and shock (11). If serologic testing indicates recent flavivirus infection that could be caused by either Zika or dengue virus, patients should be clinically managed for both infections because they might have been infected with either virus.


Asunto(s)
Anticuerpos Antivirales/aislamiento & purificación , Pruebas Diagnósticas de Rutina , Guías de Práctica Clínica como Asunto , Infección por el Virus Zika/diagnóstico , Virus Zika/inmunología , Centers for Disease Control and Prevention, U.S. , Dengue/diagnóstico , Dengue/terapia , Femenino , Humanos , Embarazo , Estados Unidos , Infección por el Virus Zika/terapia
3.
Emerg Infect Dis ; 18(2): 248-55, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22304936

RESUMEN

Nipah virus (NiV) is a highly pathogenic paramyxovirus that causes fatal encephalitis in humans. The initial outbreak of NiV infection occurred in Malaysia and Singapore in 1998-1999; relatively small, sporadic outbreaks among humans have occurred in Bangladesh since 2001. We characterized the complete genomic sequences of identical NiV isolates from 2 patients in 2008 and partial genomic sequences of throat swab samples from 3 patients in 2010, all from Bangladesh. All sequences from patients in Bangladesh comprised a distinct genetic group. However, the detection of 3 genetically distinct sequences from patients in the districts of Faridpur and Gopalganj indicated multiple co-circulating lineages in a localized region over a short time (January-March 2010). Sequence comparisons between the open reading frames of all available NiV genes led us to propose a standardized protocol for genotyping NiV; this protcol provides a simple and accurate way to classify current and future NiV sequences.


Asunto(s)
Brotes de Enfermedades , Infecciones por Henipavirus/epidemiología , Virus Nipah/genética , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Bangladesh/epidemiología , Niño , Secuencia Conservada , Femenino , Variación Genética , Genoma Viral , Infecciones por Henipavirus/virología , Humanos , Datos de Secuencia Molecular , Tipificación Molecular , Virus Nipah/aislamiento & purificación , Filogenia , Análisis de Secuencia de ADN , Estudios Seroepidemiológicos , Proteínas Virales/química , Proteínas Virales/genética
4.
PLoS One ; 3(9): e3140, 2008 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-18769550

RESUMEN

BACKGROUND: The presence of measles virus (MV) RNA in bowel tissue from children with autism spectrum disorders (ASD) and gastrointestinal (GI) disturbances was reported in 1998. Subsequent investigations found no associations between MV exposure and ASD but did not test for the presence of MV RNA in bowel or focus on children with ASD and GI disturbances. Failure to replicate the original study design may contribute to continued public concern with respect to the safety of the measles, mumps, and rubella (MMR) vaccine. METHODOLOGY/PRINCIPAL FINDINGS: The objective of this case-control study was to determine whether children with GI disturbances and autism are more likely than children with GI disturbances alone to have MV RNA and/or inflammation in bowel tissues and if autism and/or GI episode onset relate temporally to receipt of MMR. The sample was an age-matched group of US children undergoing clinically-indicated ileocolonoscopy. Ileal and cecal tissues from 25 children with autism and GI disturbances and 13 children with GI disturbances alone (controls) were evaluated by real-time reverse transcription (RT)-PCR for presence of MV RNA in three laboratories blinded to diagnosis, including one wherein the original findings suggesting a link between MV and ASD were reported. The temporal order of onset of GI episodes and autism relative to timing of MMR administration was examined. We found no differences between case and control groups in the presence of MV RNA in ileum and cecum. Results were consistent across the three laboratory sites. GI symptom and autism onset were unrelated to MMR timing. Eighty-eight percent of ASD cases had behavioral regression. CONCLUSIONS/SIGNIFICANCE: This study provides strong evidence against association of autism with persistent MV RNA in the GI tract or MMR exposure. Autism with GI disturbances is associated with elevated rates of regression in language or other skills and may represent an endophenotype distinct from other ASD.


Asunto(s)
Trastorno Autístico/etiología , Enfermedades Gastrointestinales/etiología , Vacuna Antisarampión/efectos adversos , Trastorno Autístico/complicaciones , Conducta , Estudios de Casos y Controles , Niño , Preescolar , Salud de la Familia , Femenino , Enfermedades Gastrointestinales/complicaciones , Humanos , Intestinos/virología , Masculino , Pruebas Neuropsicológicas , ARN Viral/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
5.
J Gen Virol ; 89(Pt 5): 1300-1308, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18420809

RESUMEN

Nipah virus (NiV) is a recently emergent, highly pathogenic, zoonotic paramyxovirus of the genus Henipavirus. Like the phosphoprotein (P) gene of other paramyxoviruses, the P gene of NiV is predicted to encode three additional proteins, C, V and W. When the C, V and W proteins of NiV were tested for their ability to inhibit expression of the chloramphenicol acetyltransferase (CAT) reporter gene in plasmid-based, minigenome replication assays, each protein inhibited CAT expression in a dose-dependent manner. The C, V and W proteins of NiV also inhibited expression of CAT from a measles virus (MV) minigenome, but not from a human parainfluenzavirus 3 (hPIV3) minigenome. Interestingly, the C and V proteins of MV, which have previously been shown to inhibit MV minigenome replication, also inhibited NiV minigenome replication; however, they were not able to inhibit hPIV3 minigenome replication. In contrast, the C protein of hPIV3 inhibited minigenome replication of hPIV3, NiV and MV. Although there is very limited amino acid sequence similarity between the C, V and W proteins within the paramyxoviruses, the heterotypic inhibition of replication suggests that these proteins may share functional properties.


Asunto(s)
Virus Nipah/fisiología , Proteínas Virales/metabolismo , Replicación Viral/fisiología , Animales , Línea Celular , Cloranfenicol O-Acetiltransferasa/biosíntesis , Cloranfenicol O-Acetiltransferasa/genética , Cricetinae , Genes Reporteros , Genoma Viral , Virus del Sarampión/genética , Virus del Sarampión/fisiología , Virus Nipah/genética , Virus de la Parainfluenza 3 Humana/genética , Virus de la Parainfluenza 3 Humana/fisiología , Replicación Viral/genética
6.
Am J Hematol ; 82(12): 1071-5, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17696204

RESUMEN

High-dose melphalan with autologous stem cell support improves survival as part of initial therapy for myeloma. Previous studies of pre-transplant induction regimens have compared paraprotein response rates but not long-term outcomes after transplant. We reviewed the records of all patients with multiple myeloma who received an autologous stem cell transplant at the University of Pennsylvania Medical Center. We compared outcomes for 69 patients who received high-dose melphalan conditioning after January 1, 2003 as part of initial therapy for myeloma, including 41 patients who received anthracycline-based induction (VAD or DVD) and 28 patients who received thalidomide and dexamethasone induction. Baseline characteristics in these two groups were not different, though potentially clinically important differences were apparent in assignment to post-transplant consolidation and maintenance therapy. Despite similar response rates during induction therapy, thalidomide and dexamethasone induction was associated with better progression-free survival (hazard ratio 0.18, P = 0.011) after transplant. This effect persisted in multivariable regression models including baseline characteristics and post-transplant treatment. Overall survival was not different between the two groups. These results suggest that the use of thalidomide during induction therapy may lead to improved long-term outcomes after transplant. Future trials comparing induction therapies should examine progression-free and overall survival after transplant to confirm this benefit.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Melfalán/uso terapéutico , Mieloma Múltiple/tratamiento farmacológico , Trasplante de Células Madre , Adulto , Anciano , Dexametasona/administración & dosificación , Supervivencia sin Enfermedad , Doxorrubicina/administración & dosificación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mieloma Múltiple/mortalidad , Mieloma Múltiple/patología , Mieloma Múltiple/terapia , Estadificación de Neoplasias , Estudios Retrospectivos , Análisis de Supervivencia , Talidomida/administración & dosificación , Trasplante Autólogo , Vincristina/administración & dosificación
7.
J Clin Microbiol ; 45(9): 2902-8, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17652480

RESUMEN

The mumps virus is a negative-strand RNA virus in the family Paramyxoviridae. Mumps infection results in an acute illness with symptoms including fever, headache, and myalgia, followed by swelling of the salivary glands. Complications of mumps can include meningitis, deafness, pancreatitis, orchitis, and first-trimester abortion. Laboratory confirmation of mumps infection can be made by the detection of immunoglobulin M-specific antibodies to mumps virus in acute-phase serum samples, the isolation of mumps virus in cell culture, or by detection of the RNA of the mumps virus by reverse transcription (RT)-PCR. We developed and validated a multiplex real-time RT-PCR assay for rapid mumps diagnosis in a clinical setting. This assay used oligonucleotide primers and a TaqMan probe targeting the mumps SH gene, as well as primers and a probe that targeted the human RNase P gene to assess the presence of PCR inhibitors and as a measure of specimen quality. The test was specific, since it did not amplify a product from near-neighbor viruses, as well as sensitive and accurate. Real-time RT-PCR results showed 100% correlation with results from viral culture, the gold standard for mumps diagnostic testing. Assay efficiency was over 90% and displayed good precision after performing inter- and intraassay replicates. Thus, we have developed and validated a molecular method for rapidly diagnosing mumps infection that may be used to complement existing techniques.


Asunto(s)
Virus de la Parotiditis/aislamiento & purificación , Paperas/virología , ARN Viral/sangre , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Cartilla de ADN/genética , Humanos , Datos de Secuencia Molecular , Paperas/diagnóstico , Virus de la Parotiditis/genética , Reproducibilidad de los Resultados , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/normas , Ribonucleasa P/genética , Sensibilidad y Especificidad , Estadística como Asunto , Proteínas Virales/genética , Cultivo de Virus
8.
J Virol Methods ; 132(1-2): 166-73, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16274752

RESUMEN

Real-time RT-PCR assays targeting sequences in the measles virus (MV) nucleoprotein (N), fusion (F), and hemagglutinin (H) genes were developed for the detection of MV RNA in clinical specimens. Four primer and probe sets each for the N, F, and H genes were evaluated and reaction conditions optimized. Using dilution series of synthetic RNAs, the limits of detection were determined to be approximately 10 copies for each target RNA/reaction. The relationship between C(t) values and RNA concentration was linear within a range of 10-10(6) RNA copies/reaction, and intra- and inter-assay variability was low. The N gene-specific real-time assay detected MV RNA in 100% of clinical samples from confirmed measles cases compared to 41% by standard RT-PCR. The MV H and F gene-specific real-time assays detected MV RNA in 93% and 82% of these specimens, respectively. Real-time assays could detect RNA from strains representing each active genotype of MV and were also highly specific, as no false positives were identified when samples known to contain other respiratory viruses were tested. Real-time RT-PCR assays will be available to support routine measles laboratory surveillance, to facilitate research projects on pathogenesis that require sensitive and quantitative detection of MV RNA, and to aid in the investigation of serious disease sequelae resulting from natural measles infection or vaccination with measles-containing vaccines.


Asunto(s)
Virus del Sarampión/aislamiento & purificación , Sarampión/diagnóstico , Sarampión/virología , ARN Viral/análisis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Análisis de Varianza , Animales , Línea Celular , Cartilla de ADN , Haplorrinos , Hemaglutininas Virales/genética , Humanos , Virus del Sarampión/genética , Nasofaringe/virología , Proteínas de la Nucleocápside , Nucleoproteínas/genética , Faringe/virología , ARN Viral/genética , Sensibilidad y Especificidad , Orina/virología , Proteínas Virales de Fusión/genética , Proteínas Virales/genética
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