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1.
Cureus ; 14(11): e31083, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36479403

RESUMEN

Tumors of the craniocervical junction (CCJ) are complicated pathologies with high patient mortality or low quality of life. In the pediatric population, these tumors are less prevalent, with various symptomatic presentations that include motor and neurological manifestations. Three of the most common neoplasms at the CCJ in children are meningiomas, schwannomas, and chordomas. In this review, we will characterize the tissue biomarkers, clinical presentation, treatment methods, and surgical outcomes for these pediatric tumors at the CCJ. A comprehensive literature review was used using the PubMed Database. Keywords used were "craniocervical junction", "pediatric", "meningiomas", schwannomas", and "meningiomas". Articles that were not related to the CCJ, included only adult cases, and non-English studies were filtered. Our search yielded a total of 11 studies, with a total of 239 pediatric patients with tumors at the CCJ. These studies were broken down as five for meningiomas, one for schwannomas, and eight for chordomas. In conclusion, resection of pediatric neoplasms at the CCJ is challenging due to anatomical limitations and the size of the patient. Within the CCJ, chordomas were the most prevalent tumor type, with schwannomas being the least prevalent. Literature findings indicate that genetic mutations of the NF2 gene associated with neurofibromatosis type II, as well as incomplete tumor resection, are predictors of poor outcomes. Further developments of monoclonal antibody chemotherapy and endoscopic approaches could expand treatment options for aggressive pediatric neoplasms at the skull base.

2.
Surg Neurol Int ; 12: 170, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34084598

RESUMEN

BACKGROUND: Odontoid process fractures are one of the most common spine fractures, especially in patients over age 70. There is still much controversy over the ideal candidate for anterior odontoid screw fixation (AOSF), with outcomes affected by characteristics such as fracture morphology, nonideal body habitus, and osteoporosis. Therefore, this systematic review seeks to discuss the optimal criteria, indications, and adverse postoperative considerations when deciding to pursue AOSF. METHODS: This investigation was conducted from experiential recall and article selection performed using the PubMed electronic bibliographic databases. The search yielded 124 articles that were assessed and filtered for relevance. Following the screening of titles and abstracts, 48 articles were deemed significant for final selection. RESULTS: AOSF is often utilized to treat Type IIB odontoid fractures, which has been shown to preserve atlantoaxial motion, limit soft-tissue injuries/blood loss/vertebral artery injury/reduce operative time, provide adequate osteosynthesis, incur immediate spinal stabilization, and allow motion preservation of C1 and C2. However, this technique is limited by patient characteristics such as fracture morphology, transverse ligament rupture, remote injuries, short neck or inability to extend neck, barrel chested, and severe spinal kyphosis, in addition to adverse postoperative outcomes such as dysphagia and vocal cord paralysis. CONCLUSION: Due to the fact that odontoid fractures have a significant morbidity in elderly population, treatment with AOSF is generally recommended for this population with higher risk for nonoperative fusion. Considerations should be made to achieve fracture stability and fusion, while lowering the risk for operative and postoperative complications.

3.
Neurosurg Focus ; 50(6): E10, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34062502

RESUMEN

OBJECTIVE: Spinal fusions are among the most common and effective spinal surgical practices; however, the current model presents some cost and safety concerns within the patient population. Therefore, enhanced biomaterials have been presented to be an innovative yet underutilized tool to supplement the success of spinal fusion surgery. Herein, the authors discuss these biomaterials, their compositions, clinical outcomes, and cost analysis through a systematic review of the literature to date. METHODS: This systematic review was conducted using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) criteria and guidelines. Article selection was performed using the PubMed electronic bibliographic databases. The search yielded 1168 articles that were assessed and filtered for relevance by the four authors. Following the screening of titles and abstracts, 62 articles were deemed significant enough for final selection. RESULTS: To date, silicon nitride, bioactive glass, amino peptide bone grafts, and tantalum are all biomaterials that could have significant roles in supporting spinal fusion. Their unique compositions allow them to be biocompatible in the spine, and their mechanisms of action stimulate osteoblast formation and support fusion success. Moreover, these biomaterials also present positive clinical and cost outcomes that support their application in spinal procedures. However, further studies with longer follow-ups are necessary to fully understand these biomaterials prior to their incorporation in mainstream spinal practice. CONCLUSIONS: The combination of their positive clinical outcomes, biocompatibility, and cost-effectiveness makes these biomaterials valuable, innovative, and effective treatment modalities that could revolutionize the current model of spinal fusion.


Asunto(s)
Enfermedades de la Columna Vertebral , Fusión Vertebral , Humanos , Compuestos de Silicona , Tantalio
4.
Neurol Med Chir (Tokyo) ; 61(6): 347-355, 2021 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-33967179

RESUMEN

Epilepsy is a chronic condition that affects about 50 million individuals worldwide. While its challenges are profound, there are increasing instances where antiepileptic drugs (AEDs) fail to provide relief to epileptic manifestations. For these pharmacoresistant cases, epilepsy surgery often is an effective route for treatment. However, the complexity and challenges associated with presurgical evaluations have prevented more widespread utilization of epilepsy surgery in pharmacoresistant cases. While preliminary work-ups and non-invasive diagnostic imaging have allowed for limited identification of the epileptogenic zone (EZ), there is yet to be an established pre-determined algorithm for surgical evaluation of patients with epilepsy. However, two modalities are currently being used for localization of the EZ and in determining candidates for surgery: stereoelectroencephalography (SEEG) and subdural electrodes (SDEs). SDE has been used in the United States for decades; however, SEEG now provides a less invasive option for mapping brain regions. We seek to address which intracranial monitoring technique is superior. Through a review of the outcomes of various clinical studies, SEEG was found to have greater safety and efficiency benefits than SDE, such as lower morbidity rates, lower prevalence of neurological deficits, and shorter recovery times. Moreover, SEEG was also found to have further functional benefits by allowing for deeper targeting of cerebral tissue along with bilateral hemispheric monitoring. This has led to increased rates of seizure freedom and control among SEEG patients. Nevertheless, further studies on the limitations and advancements of SEEG and SDE are still required to provide a more comprehensive understanding regarding their application.


Asunto(s)
Epilepsia , Preparaciones Farmacéuticas , Electrodos Implantados , Electroencefalografía , Epilepsia/tratamiento farmacológico , Epilepsia/cirugía , Humanos , Técnicas Estereotáxicas
5.
Arch Dis Child ; 106(7): 636-640, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33441316

RESUMEN

Estimates for the UK suggest that alcohol consumption during pregnancy and prevalence of fetal alcohol spectrum disorder (FASD)-the most common neurodevelopmental condition-are high. Considering the significant health and social impacts of FASD, there is a public health imperative to prioritise prevention, interventions and support. In this article, we outline the current state of play regarding FASD knowledge and research in the UK, which is characterised by a lack of evidence, a lack of dedicated funding and services, and consequently little policy formulation and strategic direction. We highlight progress made to date, as well as current knowledge and service gaps to propose a way forward for UK research.


Asunto(s)
Consumo de Bebidas Alcohólicas/efectos adversos , Trastornos del Espectro Alcohólico Fetal/epidemiología , Proyectos de Investigación/legislación & jurisprudencia , Adulto , Consumo de Bebidas Alcohólicas/epidemiología , Concienciación , Femenino , Trastornos del Espectro Alcohólico Fetal/diagnóstico , Trastornos del Espectro Alcohólico Fetal/prevención & control , Humanos , Lactante , Recién Nacido , Conocimiento , Trastornos del Neurodesarrollo/epidemiología , Trastornos del Neurodesarrollo/prevención & control , Embarazo , Prevalencia , Salud Pública/estadística & datos numéricos , Proyectos de Investigación/estadística & datos numéricos , Cambio Social , Reino Unido/epidemiología
6.
Child Abuse Negl ; 116(Pt 2): 104779, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33143870

RESUMEN

BACKGROUND: There is consensus in child sexual abuse (CSA) literature that intrafamilial child sexual abuse (IFCSA) has a tremendous impact on children and families while simultaneously creating challenges for practitioners. COVID-19 impacted countries worldwide and generated a global crisis resulting in impacts on daily life, however, it's effect on IFCSA is unknown. OBJECTIVE: This study aimed to compare professional perspectives and experiences working with IFCSA with respect to the context of the COVID-19 pandemic within the United States and Israel. PARTICIPANTS AND SETTING: Participants were therapeutic, child welfare and legal professionals, who provided services to children involved in IFCSA. METHODS: This qualitative cross-cultural comparative study analyzes professional experiences of IFCSA during COVID-19 based on an open-ended questionnaire answered online, with 37 responses from the US and 23 responses from Israel. RESULTS: Findings reveal mostly negative changes in the dynamics of IFCSA families during COVID-19, including financial, environmental, and emotional hardships, as well as some positive changes in the relationships among family members. In terms of professional interventions, concerns were raised that COVID-19 has been detrimental to the disclosure of IFCSA, with plummeting child abuse reports. Further, risk and benefits of transferring to internet based or telephonic therapeutic interventions were shared. CONCLUSIONS: Governmental and community efforts are needed to develop a safety net of protective factors to reduce IFCSA risks and increase resiliency during the COVID-19 pandemic and future global crises. Moreover, enhanced strategies to accessing and supporting families remotely such as using technology could improve identification and response to IFCSA.


Asunto(s)
COVID-19 , Abuso Sexual Infantil , Adulto , Anciano , Niño , Abuso Sexual Infantil/psicología , Revelación , Relaciones Familiares , Femenino , Personal de Salud/psicología , Humanos , Israel , Masculino , Persona de Mediana Edad , Pandemias , Investigación Cualitativa , SARS-CoV-2 , Encuestas y Cuestionarios , Estados Unidos
7.
Appl Environ Microbiol ; 86(18)2020 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-32680869

RESUMEN

Hand hygiene interventions are critical for reducing farmworker hand contamination and preventing the spread of produce-associated illness. Hand hygiene effectiveness may be produce-commodity specific, which could influence implementation strategies. This study's goal was to determine if produce commodity influences the ability of handwashing with soap and water or two-step alcohol-based hand sanitizer (ABHS) interventions to reduce soil and bacteria on farmworker hands. Farmworkers (n = 326) harvested produce (cantaloupe, jalapeño, and tomato) for 30 to 90 minutes before engaging in handwashing, two-step ABHS (jalapeño and cantaloupe), or no hand hygiene. Hands were rinsed to measure amounts of soil (absorbance at 600 nm) and indicator bacteria (coliforms, Enterococcus sp., generic Escherichia coli, and Bacteroidales universal [AllBac] and human-specific [BFD] 16S rRNA gene markers). Without hand hygiene, bacterial concentrations (0.88 to 5.1 log10 CFU/hand) on hands significantly differed by the produce commodity harvested. Moderate significant correlations (ρ = -0.41 to 0.56) between soil load and bacterial concentrations were observed. There were significant produce-commodity-specific differences in the ability of handwashing and two-step ABHS interventions to reduce soil (P < 0.0001), coliforms (P = 0.002), and Enterococcus sp. (P = 0.003), but not the Bacteroidales markers AllBac (P = 0.4) or BFD (P = 0.3). Contamination on hands of farmworkers who harvested cantaloupe was more difficult to remove. Overall, we found that a two-step ABHS intervention was similar to handwashing with soap and water at reducing bacteria on farmworker hands. In summary, produce commodity type should be considered when developing hand hygiene interventions on farms.IMPORTANCE This study demonstrated that the type of produce commodity handled influences the ability of handwashing with soap and water or a two-step alcohol-based hand sanitizer (ABHS) intervention to reduce soil and bacterial hand contamination. Handwashing with soap and water, as recommended by the FDA's Produce Safety Rule, when tested in three agricultural environments, does not always reduce bacterial loads. Consistent with past results, we found that the two-step ABHS method performed similarly to handwashing with soap and water but also does not always reduce bacterial loads in these contexts. Given the ease of use of the two-step ABHS method, which may increase compliance, the two-step ABHS method should be further evaluated and possibly considered for implementation in the agricultural environment. Taken together, these results provide important information on hand hygiene effectiveness in three agricultural contexts.


Asunto(s)
Carga Bacteriana/efectos de los fármacos , Producción de Cultivos , Productos Agrícolas/clasificación , Desinfección de las Manos/instrumentación , Desinfectantes para las Manos/administración & dosificación , Mano/microbiología , Suelo , Capsicum/crecimiento & desarrollo , Cucumis melo/crecimiento & desarrollo , Etanol/química , Agricultores , Desinfectantes para las Manos/química , Humanos , Solanum lycopersicum/crecimiento & desarrollo , México
8.
Child Abuse Negl ; 105: 104317, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-31843211

RESUMEN

BACKGROUND: Early intervention efforts designed for youth with problematic sexual behavior (PSB) have strong promise. Prompt identification of youth with PSB is critical to ensuring early intervention and effective response. OBJECTIVE: The current study explored the complexities of how PSB of youth is identified in the community. SETTING: A qualitative semi-structured interview approach was utilized to explore the perceptions and experiences of community members involved in cases of youth with PSB. PARTICIPANTS: Participants included 100 community members from eight geographically diverse locations in the United States. METHOD: Themes involving identification of PSB were classified by qualitative analyses, beginning with thematic analysis followed by focused coding. RESULTS: Results indicated multiple pathways for the identification of youth with PSB involving a variety of professionals and agencies. Victim disclosure and witnessing the PSB were the most common identification pathways, with caregivers and school personnel the most common initial identifiers. Once identified, cases were reported to child welfare, law enforcement, and/or behavioral health agencies. Complications due to unclear response pathways and fears held by caregivers were notable. CONCLUSIONS: Developmentally appropriate, evidence-informed policies and procedures for the identification of and response to PSB in youth within and across professions would facilitate a public health response to for prevention and early responses to PSB of youth.


Asunto(s)
Protección a la Infancia/legislación & jurisprudencia , Revelación , Políticas , Problema de Conducta , Conducta Sexual , Adolescente , Cuidadores/psicología , Niño , Familia/psicología , Femenino , Humanos , Masculino , Prevalencia , Investigación Cualitativa , Factores de Riesgo , Estados Unidos
10.
J Community Psychol ; 47(6): 1347-1363, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31017312

RESUMEN

AIMS: Community management of youth with problematic sexual behavior (PSB) is complex. Public policies and service practices have historically utilized adult-focused approaches with limited research outcomes. This descriptive case study aimed to address this gap by documenting current PSB policies and policy reforms for community-based management systems. METHOD: Semi-structured interviews with 219 professionals from eight urban and rural communities throughout the United States served as the primary data source for the study. The three-stage Framework Method was used to guide the data analysis process. RESULTS: This study covered three areas: context of policy development, attitudes, and perceptions of policy for youth with PSB, and existing policy and policy reform initiatives. CONCLUSION: Findings support benefits of collaborative multidisciplinary teams that cross agency policies and procedures on management of cases involving youth with PSB. Implications for practitioners, policymakers, and community members are discussed.


Asunto(s)
Problema de Conducta/psicología , Población Rural/estadística & datos numéricos , Conducta Sexual/psicología , Población Urbana/estadística & datos numéricos , Adolescente , Actitud , Niño , Análisis de Datos , Humanos , Comunicación Interdisciplinaria , Entrevistas como Asunto/métodos , Masculino , Percepción/fisiología , Políticas , Investigación Cualitativa , Estados Unidos/epidemiología
11.
Cell Host Microbe ; 25(1): 59-72.e8, 2019 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-30629920

RESUMEN

Eliciting HIV-1-specific broadly neutralizing antibodies (bNAbs) remains a challenge for vaccine development, and the potential of passively delivered bNAbs for prophylaxis and therapeutics is being explored. We used neutralization data from four large virus panels to comprehensively map viral signatures associated with bNAb sensitivity, including amino acids, hypervariable region characteristics, and clade effects across four different classes of bNAbs. The bNAb signatures defined for the variable loop 2 (V2) epitope region of HIV-1 Env were then employed to inform immunogen design in a proof-of-concept exploration of signature-based epitope targeted (SET) vaccines. V2 bNAb signature-guided mutations were introduced into Env 459C to create a trivalent vaccine, and immunization of guinea pigs with V2-SET vaccines resulted in increased breadth of NAb responses compared with Env 459C alone. These data demonstrate that bNAb signatures can be utilized to engineer HIV-1 Env vaccine immunogens capable of eliciting antibody responses with greater neutralization breadth.


Asunto(s)
Anticuerpos Neutralizantes/inmunología , Epítopos/inmunología , Anticuerpos Anti-VIH/inmunología , Infecciones por VIH/inmunología , Infecciones por VIH/prevención & control , Vacunas , Secuencia de Aminoácidos , Animales , Anticuerpos Neutralizantes/uso terapéutico , Formación de Anticuerpos , Modelos Animales de Enfermedad , Epítopos/genética , Femenino , Cobayas , Células HEK293 , Proteína gp120 de Envoltorio del VIH/inmunología , Infecciones por VIH/virología , VIH-1/genética , Humanos , Inmunización , Concentración 50 Inhibidora , Modelos Moleculares , Mutación , Fragmentos de Péptidos/inmunología , Unión Proteica , Vacunación , Productos del Gen env del Virus de la Inmunodeficiencia Humana/genética , Productos del Gen env del Virus de la Inmunodeficiencia Humana/inmunología
12.
Environ Sci Technol ; 52(10): 5868-5874, 2018 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-29671314

RESUMEN

Recent tightening of particulate matter (PM) emission standards for heavy-duty engines has spurred the widespread adoption of diesel particulate filters (DPFs), which need to be regenerated periodically to remove trapped PM. The total impact of DPFs therefore depends not only on their filtering efficiency during normal operation, but also on the emissions during and the frequency of regeneration events. We performed active (parked and driving) and passive regenerations on two heavy-duty diesel vehicles (HDDVs), and report the chemical composition of emissions during these events, as well as the efficiency with which trapped PM is converted to gas-phase products. We also collected activity data from 85 HDDVs to determine how often regeneration occurs during real-world operation. PM emitted during regeneration ranged from 0.2 to 16.3 g, and the average time and distance between real-world active regenerations was 28.0 h and 599 miles. These results indicate that regeneration of real-world DPFs does not substantially offset the reduction of PM by DPFs during normal operation. The broad ranges of regeneration frequency per truck (3-100 h and 23-4078 miles) underscore the challenges in designing engines and associated aftertreatments that reduce emissions for all real-world duty cycles.


Asunto(s)
Contaminantes Atmosféricos , Emisiones de Vehículos , Polvo , Vehículos a Motor , Material Particulado
13.
J Virol ; 92(13)2018 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-29643249

RESUMEN

A vaccination regimen capable of eliciting potent and broadly neutralizing antibodies (bNAbs) remains an unachieved goal of the HIV-1 vaccine field. Here, we report the immunogenicity of longitudinal prime/boost vaccination regimens with a panel of HIV-1 envelope (Env) gp140 protein immunogens over a period of 200 weeks in guinea pigs. We assessed vaccine regimens that included a monovalent clade C gp140 (C97ZA012 [C97]), a tetravalent regimen consisting of four clade C gp140s (C97ZA012, 459C, 405C, and 939C [4C]), and a tetravalent regimen consisting of clade A, B, C, and mosaic gp140s (92UG037, PVO.4, C97ZA012, and Mosaic 3.1, respectively [ABCM]). We found that the 4C and ABCM prime/boost regimens were capable of eliciting greater magnitude and breadth of binding antibody responses targeting variable loop 2 (V2) over time than the monovalent C97-only regimen. The longitudinal boosting regimen conducted over more than 2 years increased the magnitude of certain tier 1 NAb responses but did not increase the magnitude or breadth of heterologous tier 2 NAb responses. These data suggest that additional immunogen design strategies are needed to induce broad, high-titer tier 2 NAb responses.IMPORTANCE The elicitation of potent, broadly neutralizing antibodies (bNAbs) remains an elusive goal for the HIV-1 vaccine field. In this study, we explored the use of a long-term vaccination regimen with different immunogens to determine if we could elicit bNAbs in guinea pigs. We found that longitudinal boosting over more than 2 years increased tier 1 NAb responses but did not increase the magnitude and breadth of tier 2 NAb responses. These data suggest that additional immunogen designs and vaccination strategies will be necessary to induce broad tier 2 NAb responses.


Asunto(s)
Vacunas contra el SIDA/administración & dosificación , Anticuerpos Neutralizantes/metabolismo , VIH-1/clasificación , Productos del Gen env del Virus de la Inmunodeficiencia Humana/química , Vacunas contra el SIDA/inmunología , Animales , Femenino , Cobayas , Anticuerpos Anti-VIH/metabolismo , VIH-1/inmunología , Inmunización Secundaria , Estudios Longitudinales , Vacunación , Productos del Gen env del Virus de la Inmunodeficiencia Humana/inmunología
14.
Prev Sci ; 19(4): 528-537, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29022144

RESUMEN

Beginning parenting programs in the prenatal and early postnatal periods have a large potential for impact on later child and maternal outcomes. Home-based parenting programs, such as the Nurse Family Partnership (NFP), have been established to help address this need. Program reach and impact is dependent on successful engagement of expecting mothers with significant risks; however, NFP attrition rates remain high. The current study qualitatively examined engagement and attrition from the perspectives of NFP nurses and mothers in order to identify mechanisms that enhance service engagement. Semi-structured interviews were conducted in focus groups composed of either engaged (27 total mothers) or unengaged (15 total mothers) mothers from the NFP program. NFP nurses (25 total nurses) were recruited for individual semi-structured interviews. Results suggest that understanding engagement in the NFP program requires addressing both initial and sustained engagement. Themes associated with enhanced initial engagement include nurse characteristics (e.g., flexible, supportive, caring) and establishment of a solid nurse-family relationship founded on these characteristics. Factors impacting sustained engagement include nurse characteristics, provision of educational materials on child development, individualized services for families, and available family support. Identified barriers to completing services include competing demands and lack of support. Findings of this study have direct relevance for workforce planning, including hiring and training through integrating results regarding effective nurse characteristics. Additional program supports to enhance parent engagement may be implemented across home-based parenting programs in light of the current study's findings.


Asunto(s)
Servicios de Atención de Salud a Domicilio , Visita Domiciliaria , Aceptación de la Atención de Salud , Adulto , Femenino , Grupos Focales , Humanos , Entrevistas como Asunto , Persona de Mediana Edad , Aceptación de la Atención de Salud/estadística & datos numéricos , Atención Posnatal , Relaciones Profesional-Familia , Evaluación de Programas y Proyectos de Salud , Investigación Cualitativa , Adulto Joven
15.
Clin Pediatr (Phila) ; 56(11): 1032-1039, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28403659

RESUMEN

Vaccinations are considered one of public health's greatest accomplishments. Despite evidence for vaccine effectiveness, uptake levels are still well below the Centers for Disease Control and Prevention's guidelines. The immunization decision-making process for parents is complex and depends on factors associated with knowledge and experiences. This qualitative study sought to expand on a previous decision-making model for immunizations by examining how individuals receive vaccination information, determining the role of experience in influencing decisions, and understanding how young adults might locate vaccination information in the future. Three focus groups were conducted with 29 undergraduate students without children. Results suggest that young adults exhibit an awareness of information regarding vaccine use and effectiveness, value doctor opinions and recommendations, and desire more robust research on vaccinations. Implications of these results include the importance of (1) disseminating vaccination education to young adults, (2) enhancing consistency/trust between medical professionals and youth, and (3) expanding public policy to increase vaccine uptake.


Asunto(s)
Toma de Decisiones , Conocimientos, Actitudes y Práctica en Salud , Inmunización/psicología , Padres/psicología , Adulto , Femenino , Grupos Focales , Humanos , Lactante , Masculino , Investigación Cualitativa , Adulto Joven
16.
Vaccine ; 35(1): 1-9, 2017 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-27899229

RESUMEN

An important focus in vaccine research is the design of vaccine vectors with low seroprevalence and high immunogenicity. Replication-incompetent lymphocytic choriomeningitis virus (rLCMV) vectors do not elicit vector-neutralizing antibody responses, and homologous prime-boost regimens with rLCMV vectors induce boostable and protective T cell responses to model antigens in mice. However, cellular and humoral immune responses following homologous rLCMV vaccine regimens have not been rigorously evaluated in non-human primates (NHPs). To test whether rLCMV vectors constitute an effective vaccine platform in NHPs, we developed rLCMV vectors expressing SIVmac239 Env and Gag antigens and assessed their immunogenicity in mice and cynomolgus macaques. Immunization with rLCMV vaccine vectors expressing SIV Env and Gag was effective at generating SIV-specific T cell and antibody responses in both mice and NHPs. Epitope mapping using SIV Env in C57BL/6 mice demonstrated that rLCMV vectors induced sustained poly-functional responses to both dominant and subdominant epitopes. Our results suggest the potential of rLCMV vectors as vaccine candidates. Future SIV challenge experiments in rhesus macaques will be needed to assess immune protection by these vaccine vectors.


Asunto(s)
Antígenos Virales/inmunología , Portadores de Fármacos , Virus de la Coriomeningitis Linfocítica/genética , Vacunas contra el SIDAS/inmunología , Virus de la Inmunodeficiencia de los Simios/inmunología , Animales , Anticuerpos Antivirales/sangre , Antígenos Virales/genética , Macaca fascicularis , Ratones Endogámicos C57BL , Vacunas contra el SIDAS/administración & dosificación , Vacunas contra el SIDAS/genética , Virus de la Inmunodeficiencia de los Simios/genética , Linfocitos T/inmunología , Vacunas Atenuadas/administración & dosificación , Vacunas Atenuadas/genética , Vacunas Atenuadas/inmunología , Vacunas Sintéticas/administración & dosificación , Vacunas Sintéticas/genética , Vacunas Sintéticas/inmunología
17.
Open Forum Infect Dis ; 3(2): ofw100, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27419172

RESUMEN

The examination of antibody responses in human immunodeficiency virus (HIV)-1-infected individuals in the setting of antiretroviral treatment (ART) interruption can provide insight into the evolution of antibody responses during viral rebound. In this study, we assessed antibody responses in 20 subjects in AIDS Clinical Trials Group A5187, wherein subjects were treated with antiretroviral therapy during acute/early HIV-1 infection, underwent analytic treatment interruption, and subsequently demonstrated viral rebound. Our data suggest that early initiation of ART arrests the maturation of HIV-1-specific antibody responses, preventing epitope diversification of antibody binding and the development of functional neutralizing capacity. Antibody responses do not appear permanently blunted, however, because viral rebound triggered the resumption of antibody maturation in our study. We also found that antibody responses measured by these assays did not predict imminent viral rebound. These data have important implications for the HIV-1 vaccine and eradication fields.

18.
Science ; 349(6245): 320-4, 2015 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-26138104

RESUMEN

Preclinical studies of viral vector-based HIV-1 vaccine candidates have previously shown partial protection against neutralization-resistant virus challenges in rhesus monkeys. In this study, we evaluated the protective efficacy of adenovirus serotype 26 (Ad26) vector priming followed by purified envelope (Env) glycoprotein boosting. Rhesus monkeys primed with Ad26 vectors expressing SIVsmE543 Env, Gag, and Pol and boosted with AS01B-adjuvanted SIVmac32H Env gp140 demonstrated complete protection in 50% of vaccinated animals against a series of repeated, heterologous, intrarectal SIVmac251 challenges that infected all controls. Protective efficacy correlated with the functionality of Env-specific antibody responses. Comparable protection was also observed with a similar Ad/Env vaccine against repeated, heterologous, intrarectal SHIV-SF162P3 challenges. These data demonstrate robust protection by Ad/Env vaccines against acquisition of neutralization-resistant virus challenges in rhesus monkeys.


Asunto(s)
Vacunas contra el SIDA/inmunología , Vacunas contra el Adenovirus/inmunología , Productos del Gen env/inmunología , VIH-1/inmunología , Vacunas contra el SIDAS/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/prevención & control , Traslado Adoptivo , Animales , Anticuerpos Neutralizantes/inmunología , Femenino , Productos del Gen gag/inmunología , Productos del Gen pol/inmunología , Vectores Genéticos/inmunología , Antígenos de Histocompatibilidad Clase I/genética , Antígenos de Histocompatibilidad Clase I/inmunología , Inmunización Secundaria , Macaca mulatta , Masculino , Virus de la Inmunodeficiencia de los Simios/inmunología
19.
Food Environ Virol ; 7(1): 32-40, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25344785

RESUMEN

Human noroviruses (HuNoV) are a leading cause of foodborne disease and are known to be environmentally persistent. Foods usually become contaminated by contact with fecal material, both on hands and on surfaces. Emerging evidence suggests that HuNoVs are also shed and potentially aerosolized during projectile vomiting, resulting in another source of contamination. The purpose of this study was to compare the persistence of HuNoV in vomitus-like material (simulated gastric fluid, SGF, pH 2.5) to that in a pH neutral buffer (phosphate buffered saline, PBS, pH 7.4) in suspension and on surfaces. Human fecal suspensions containing two HuNoV strains (GI.1 and GII.4) were suspended in SGF and PBS. Suspension and surface samples were held at room temperature, and subsamples were collected from both samples for a period up to 42 days. Subsamples were subjected to RNA isolation, with and without inclusion of an RNase pre-treatment, followed by RT-qPCR amplification. In suspension assays, the genome copy number of HuNoV GII.4 decreased by ≤1.0-1.3 log10 over 42 days, irrespective of suspension buffer. On stainless steel, there was virtually no reduction in HuNoV GII.4 RT-qPCR signal over the 42-days experimental period, regardless of suspension buffer. Overall, the GI.1 RT-qPCR signal dropped more precipitously. In most cases, there were no statistically significant differences (p > 0.05) between persistence in solution or on surfaces when comparing RT-qPCR assays with and without prior RNase treatment. This study suggests that HuNoV suspended in vomitus-like material can persist for long periods, a likely contributor to foodborne transmission.


Asunto(s)
Ácidos/farmacología , Ácido Gástrico/química , Norovirus/efectos de los fármacos , Norovirus/aislamiento & purificación , Humanos , Concentración de Iones de Hidrógeno , Modelos Biológicos , Norovirus/genética , Reacción en Cadena en Tiempo Real de la Polimerasa
20.
J Virol ; 89(5): 2507-19, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25540368

RESUMEN

UNLABELLED: The sequence diversity of human immunodeficiency virus type 1 (HIV-1) presents a formidable challenge to the generation of an HIV-1 vaccine. One strategy to address such sequence diversity and to improve the magnitude of neutralizing antibodies (NAbs) is to utilize multivalent mixtures of HIV-1 envelope (Env) immunogens. Here we report the generation and characterization of three novel, acute clade C HIV-1 Env gp140 trimers (459C, 405C, and 939C), each with unique antigenic properties. Among the single trimers tested, 459C elicited the most potent NAb responses in vaccinated guinea pigs. We evaluated the immunogenicity of various mixtures of clade C Env trimers and found that a quadrivalent cocktail of clade C trimers elicited a greater magnitude of NAbs against a panel of tier 1A and 1B viruses than any single clade C trimer alone, demonstrating that the mixture had an advantage over all individual components of the cocktail. These data suggest that vaccination with a mixture of clade C Env trimers represents a promising strategy to augment vaccine-elicited NAb responses. IMPORTANCE: It is currently not known how to generate potent NAbs to the diverse circulating HIV-1 Envs by vaccination. One strategy to address this diversity is to utilize mixtures of different soluble HIV-1 envelope proteins. In this study, we generated and characterized three distinct, novel, acute clade C soluble trimers. We vaccinated guinea pigs with single trimers as well as mixtures of trimers, and we found that a mixture of four trimers elicited a greater magnitude of NAbs than any single trimer within the mixture. The results of this study suggest that further development of Env trimer cocktails is warranted.


Asunto(s)
Vacunas contra el SIDA/inmunología , Anticuerpos Neutralizantes/sangre , Anticuerpos Anti-VIH/sangre , VIH-1/inmunología , Vacunación/métodos , Productos del Gen env del Virus de la Inmunodeficiencia Humana/inmunología , Vacunas contra el SIDA/administración & dosificación , Animales , Femenino , Cobayas , Resultado del Tratamiento
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