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1.
J Neurosci ; 43(10): 1845-1857, 2023 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-36759193

RESUMEN

Mitochondrial dysfunction is an early event in the pathogenesis of neurologic disorders and aging. Sirtuin 3 (SIRT3) regulates mitochondrial function in response to the cellular environment through the reversible deacetylation of proteins involved in metabolism and reactive oxygen species detoxification. As the primary mitochondrial deacetylase, germline, or peripheral tissue-specific deletion of SIRT3 produces mitochondrial hyperacetylation and the accelerated development of age-related diseases. Given the unique metabolic demands of neurons, the role of SIRT3 in the brain is only beginning to emerge. Using mass spectrometry-based acetylomics, high-resolution respirometry, video-EEG, and cognition testing, we report targeted deletion of SIRT3 from select neurons in the cortex and hippocampus produces altered neuronal excitability and metabolic dysfunction in female mice. Targeted deletion of SIRT3 from neuronal helix-loop-helix 1 (NEX)-expressing neurons resulted in mitochondrial hyperacetylation, female-specific superoxide dismutase-2 (SOD2) modification, increased steady-state superoxide levels, metabolic reprogramming, altered neuronal excitability, and working spatial memory deficits. Inducible neuronal deletion of SIRT3 likewise produced female-specific deficits in spatial working memory. Together, the data demonstrate that deletion of SIRT3 from forebrain neurons selectively predisposes female mice to deficits in mitochondrial and cognitive function.SIGNIFICANCE STATEMENT Mitochondrial SIRT3 is an enzyme shown to regulate energy metabolism and antioxidant function, by direct deacetylation of proteins. In this study, we show that neuronal SIRT3 deficiency renders female mice selectively vulnerable to impairment in redox and metabolic function, spatial memory, and neuronal excitability. The observed sex-specific effects on cognition and neuronal excitability in female SIRT3-deficient mice suggest that mitochondrial dysfunction may be one factor underlying comorbid neuronal diseases, such as Alzheimer's disease and epilepsy. Furthermore, the data suggest that SIRT3 dysfunction may predispose females to age-related metabolic and cognitive impairment.


Asunto(s)
Sirtuina 3 , Masculino , Ratones , Femenino , Animales , Sirtuina 3/genética , Neuronas/metabolismo , Mitocondrias/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Envejecimiento/metabolismo , Acetilación
2.
J Pharmacol Exp Ther ; 388(2): 358-366, 2024 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-37652711

RESUMEN

Reactive oxygen species have an emerging role in the pathologic consequences of status epilepticus. We have previously demonstrated the efficacy of a water-for-injection formulation of the meso-porphyrin catalytic antioxidant, manganese (III) meso-tetrakis (N-N-diethylimidazole) porphyrin (AEOL10150) against oxidative stress, neuroinflammation, and neuronal death initiated by kainic acid, pilocarpine, diisopropylflurophosphate (DFP), and soman. This previous dose and dosing strategy of AEOL10150 required smaller multiple daily injections, precluding our ability to test its efficacy against delayed consequences of nerve agent exposure such as neurodegeneration and cognitive dysfunction. Therefore, we developed formulations of AEOL10150 designed to deliver a larger dose once daily with improved brain pharmacodynamics. We examined four new formulations of AEOL10150 that resulted in 8 times higher subcutaneous dose with lower acute toxicity, slower absorption, longer half-life, and higher maximal plasma concentrations compared with our previous strategy. AEOL10150 brain levels exhibited improved pharmacodynamics over 24 hours with all four formulations. We tested a subcutaneous dose of 40 mg/kg AEOL10150 in two formulations (2% carboxymethyl cellulose and 4% polyethylene glycol-4000) in the DFP rat model, and both formulations exhibited significant protection against DFP-induced oxidative stress. Additionally, and in one formulation (4% polyethylene glycol-4000), AEOL10150 significantly protected against DFP-induced neuronal death, microglial activation, delayed memory impairment, and mortality. These results suggest that reformulation of AEOL10150 can attenuate acute and delayed outcomes of organophosphate neurotoxicity. SIGNIFICANCE STATEMENT: Reformulation of manganese (III) meso-tetrakis (N-N-diethylimidazole) porphyrin allowed higher tolerated doses of the compound with improved pharmacodynamics. Specifically, one new formulation allowed fewer daily doses and improvement in acute and delayed outcomes of organophosphate toxicity.


Asunto(s)
Disfunción Cognitiva , Metaloporfirinas , Agentes Nerviosos , Ratas , Animales , Antioxidantes/farmacología , Antioxidantes/uso terapéutico , Ratas Sprague-Dawley , Agentes Nerviosos/toxicidad , Enfermedades Neuroinflamatorias , Manganeso , Estrés Oxidativo , Metaloporfirinas/farmacología , Metaloporfirinas/uso terapéutico , Organofosfatos , Polietilenglicoles
3.
Chem Rec ; 24(9): e202400057, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39162777

RESUMEN

Catalysis has been at the forefront of the developments that has revolutionised synthesis and provided the impetus in the discovery of platform technologies for efficient C-C or C-X bond formation. Current environmental situation however, demands a change in strategy with catalysis being promoted more in solvents that are benign (Water) and for that the development of hydrophilic ligands (especially phosphines) is a necessity which could promote catalytic reactions in water, allow recyclability of the catalytic solutions and make it possible to isolate products using column-free techniques that involve lesser usage of hazardous organic solvents. In this review, we therefore critically analyse such catalytic processes providing examples that do follow the above-mentioned parameter.

4.
MMWR Morb Mortal Wkly Rep ; 73(19): 430-434, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38753544

RESUMEN

Measles is a highly infectious, vaccine-preventable disease that can cause severe illness, hospitalization, and death. A measles outbreak associated with a migrant shelter in Chicago occurred during February-April 2024, in which a total of 57 confirmed cases were identified, including 52 among shelter residents, three among staff members, and two among community members with a known link to the shelter. CDC simulated a measles outbreak among shelter residents using a dynamic disease model, updated in real time as additional cases were identified, to produce outbreak forecasts and assess the impact of public health interventions. As of April 8, the model forecasted a median final outbreak size of 58 cases (IQR = 56-60 cases); model fit and prediction range improved as more case data became available. Counterfactual analysis of different intervention scenarios demonstrated the importance of early deployment of public health interventions in Chicago, with a 69% chance of an outbreak of 100 or more cases had there been no mass vaccination or active case-finding compared with only a 1% chance when those interventions were deployed. This analysis highlights the value of using real-time, dynamic models to aid public health response, set expectations about outbreak size and duration, and quantify the impact of interventions. The model shows that prompt mass vaccination and active case-finding likely substantially reduced the chance of a large (100 or more cases) outbreak in Chicago.


Asunto(s)
Brotes de Enfermedades , Sarampión , Humanos , Brotes de Enfermedades/prevención & control , Chicago/epidemiología , Sarampión/epidemiología , Sarampión/prevención & control , Modelos Epidemiológicos , Salud Pública , Factores de Tiempo , Predicción , Adolescente , Niño , Preescolar , Vacunación Masiva , Adulto
5.
Pharm Dev Technol ; 29(5): 492-503, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38682603

RESUMEN

Bedaquiline fumarate (BQF) is classified as a BCS class II drug and has poor water solubility and dissolution rate, which ultimately compromises bioavailability. The objective of this study is to improve the biopharmaceutical properties of BQF through a solid dispersion system by using Soluplus®. Two solid dispersion systems were prepared i.e. binary solid dispersion (BSD) and ternary solid dispersion (TSD) where 14.31-fold and 20.43-fold increase in solubility of BQF was observed with BSD and TSD in comparison to BQF. In our previous research work, we explored the BSD and TSD of BQF with a crystalline polymer, poloxamer 188, which showed an increment in the solubility of BQF. In the current research, amorphous Soluplus® polymer was selected to formulate BSD and TSD with BQF and showed higher solubility than poloxamer 188. The various solid and liquid state characterization results confirmed the presence of an amorphous form of BQF inside solid dispersion. The Fourier transform infrared spectroscopy showed no chemical interactions between BQF and polymer. The cellular uptake results demonstrated higher uptake in Caco-2 cell lines. Pharmacokinetic studies showed enhanced solubility and bioavailability of TSDs. Hence, the present research shows a promising formulation strategy for enhancing the biopharmaceutical performance of BQF by increasing its solubility.


Asunto(s)
Disponibilidad Biológica , Diarilquinolinas , Polietilenglicoles , Polivinilos , Solubilidad , Polivinilos/química , Células CACO-2 , Humanos , Animales , Diarilquinolinas/farmacocinética , Diarilquinolinas/química , Diarilquinolinas/farmacología , Polietilenglicoles/química , Masculino , Ratas , Composición de Medicamentos/métodos , Química Farmacéutica/métodos , Antituberculosos/farmacocinética , Antituberculosos/química , Antituberculosos/farmacología , Antituberculosos/administración & dosificación , Poloxámero/química
6.
Infect Immun ; 90(1): e0033921, 2022 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-34662210

RESUMEN

Contact lenses are biomaterials worn on the eye to correct refractive errors. Bacterial adhesion and colonization of these lenses results in adverse events, such as microbial keratitis. The adsorption of tear proteins to contact lens materials enhances bacterial adhesion. Glycoprotein 340 (Gp340), a tear component, is known to promote microbial colonization in the oral cavity; however, it has not been investigated in any contact lens-related adverse event. Therefore, this study examined the adsorption of Gp340 and its recombinantly expressed scavenger receptor cysteine-rich (iSRCR1Gp340) domain on two common contact lens materials, etafilcon A and lotrafilcon B, and the concomitant effects on the adherence of clinical isolates of microbial keratitis causative agents, Pseudomonas aeruginosa (PA6206; PA6294), and Staphylococcus aureus (SA38; USA300). Across all strains and materials, iSRCR1Gp340 enhanced adherence of bacteria in a dose-dependent manner. However, iSRCR1Gp340 did not modulate the lysozyme's or lactoferrin's effects on bacterial adhesion to the contact lens. The Gp340 binding serine-rich surface protein (SraP) significantly enhanced the binding of USA300 to iSRCR1Gp340-coated lenses. In addition, iSRCR1Gp340-coated surfaces had significantly diminished biofilms with the SraP mutant (ΔSraP), and there was a further reduction in biofilms with the sortase A mutant (ΔSrtA), indicating the likely involvement of additional surface proteins. Finally, the binding affinities between iSRCR1Gp340 and SraP were determined using surface plasmon resonance (SPR), where the complete SraP binding region displayed nanomolar affinity, whereas its smaller fragments adhered with micromolar affinities. This study concludes that Gp340 and its SRCR domains play an important role in bacterial adhesion to the contact lens.


Asunto(s)
Adhesión Bacteriana , Lentes de Contacto , Polímeros , Dominios y Motivos de Interacción de Proteínas , Pseudomonas aeruginosa/fisiología , Receptores Inmunológicos/metabolismo , Staphylococcus aureus/fisiología , Adhesinas Bacterianas/metabolismo , Biopelículas , Interacciones Huésped-Patógeno , Humanos , Hidrogeles , Metacrilatos , Muramidasa/metabolismo , Unión Proteica , Receptores Inmunológicos/química , Siliconas
7.
Clin Infect Dis ; 75(3): 416-424, 2022 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-34849648

RESUMEN

BACKGROUND: Measles elimination (interruption of endemic measles virus transmission) in the United States was declared in 2000; however, the number of cases and outbreaks have increased in recent years. We characterized the epidemiology of measles outbreaks and measles transmission patterns after elimination to identify potential gaps in the US measles control program. METHODS: We analyzed national measles notification data from 1 January 2001 to 31 December 2019. We defined measles infection clusters as single cases (isolated cases not linked to additional cases), 2-case clusters, or outbreaks with ≥3 linked cases. We calculated the effective reproduction number (R) to assess changes in transmissibility and reviewed molecular epidemiology data. RESULTS: During 2001-2019, a total of 3873 measles cases, including 747 international importations, were reported in the United States; 29% of importations were associated with outbreaks. Among 871 clusters, 69% were single cases and 72% had no spread. Larger and longer clusters were reported since 2013, including 7 outbreaks with >50 cases lasting >2 months, 5 of which occurred in known underimmunized, close-knit communities. No measles lineage circulated in a single transmission chain for >12 months. Higher estimates of R were noted in recent years, although R remained below the epidemic threshold of 1. CONCLUSIONS: Current epidemiology continues to support the interruption of endemic measles virus transmission in the United States. However, larger and longer outbreaks in recent postelimination years and emerging trends of increased transmission in underimmunized communities emphasize the need for targeted approaches to close existing immunity gaps and maintain measles elimination.


Asunto(s)
Epidemias , Sarampión , Número Básico de Reproducción , Brotes de Enfermedades , Humanos , Sarampión/epidemiología , Sarampión/prevención & control , Vacuna Antisarampión , Virus del Sarampión/genética , Estados Unidos/epidemiología , Vacunación
8.
J Infect Dis ; 224(12 Suppl 2): S420-S428, 2021 09 30.
Artículo en Inglés | MEDLINE | ID: mdl-34590128

RESUMEN

The global measles vaccination program has been extraordinarily successful in reducing measles-related disease and deaths worldwide. Eradication of measles is feasible because of several key attributes, including humans as the only reservoir for the virus, broad access to diagnostic tools that can rapidly detect measles-infectious persons, and availability of highly safe and effective measles-containing vaccines (MCVs). All 6 World Health Organization (WHO) regions have established measles elimination goals. Globally, during 2000-2018, measles incidence decreased by 66% (from 145 to 49 cases per million population) and deaths decreased by 73% (from 535 600 to 142 300), drastically reducing global disease burden. Routine immunization with MCV has been the cornerstone for the control and prevention of measles. Two doses of MCV are 97% effective in preventing measles, qualifying MCV as one of the most effective vaccines ever developed. Mild adverse events occur in <20% of recipients and serious adverse events are extremely rare. The economic benefits of measles vaccination are highlighted by an overall return on investment of 58 times the cost of the vaccine, supply chains, and vaccination. Because measles is one of the most contagious human diseases, maintenance of high (≥95%) 2-dose MCV coverage is crucial for controlling the spread of measles and successfully reaching measles elimination; however, the plateauing of global MCV coverage for nearly a decade and the global measles resurgence during 2018-2019 demonstrate that much work remains. Global commitments to increase community access to and demand for immunizations, strengthen national and regional partnerships for building public health infrastructure, and implement innovations that can overcome access barriers and enhance vaccine confidence, are essential to achieve a world free of measles.


Asunto(s)
Erradicación de la Enfermedad , Salud Global , Vacuna Antisarampión/administración & dosificación , Virus del Sarampión/inmunología , Sarampión/prevención & control , Erradicación de la Enfermedad/tendencias , Humanos , Programas de Inmunización , Incidencia , Lactante , Sarampión/epidemiología , Virus del Sarampión/aislamiento & purificación , Vigilancia de la Población , Organización Mundial de la Salud
9.
J Bacteriol ; 203(20): e0017521, 2021 09 23.
Artículo en Inglés | MEDLINE | ID: mdl-34339301

RESUMEN

Streptococcus intermedius, an oral commensal bacterium, is found at various sites, including subgingival dental plaque, purulent infections, and cystic fibrosis lungs. Oral streptococci utilize proteins on their surface to adhere to tissues and/or surfaces localizing the bacteria, which subsequently leads to the development of biofilms, colonization, and infection. Among the 19 genomically annotated cell wall-attached surface proteins on S. intermedius, Pas is an adhesin that belongs to the antigen I/II (AgI/II) family. Here, we have structurally and functionally characterized Pas, particularly focusing on its microbial-host as well as microbial-microbial interactions. The crystal structures of VPas and C123Pas show high similarity with AgI/II of Streptococcus mutans. VPas hosts a conserved metal binding site, and likewise, the C123Pas structure retains its conserved metal binding sites and isopeptide bonds within its three DEv-IgG domains. Pas interacts with nanomolar affinity to lung alveolar glycoprotein 340 (Gp340), its scavenger receptor cysteine-rich domains (SRCRs), and with fibrinogen. Both Candida albicans and Pseudomonas aeruginosa, the opportunistic pathogens that cohabitate with S. intermedius in the lungs of CFTR patients were studied in dual-species biofilm studies. The Pas-deficient mutant (Δpas) displayed significant reduction in dual-biofilm formation with C. albicans. In similar studies with P. aeruginosa, Pas did not mediate the biofilm formation with either the acute isolate (PAO1) or the chronic isolate (FRD1). However, the sortase A-deficient mutant (ΔsrtA) displayed reduced biofilm formation with both C. albicans and P. aeruginosa FRD1. Taken together, our findings highlight the role of Pas in both microbial-host and interkingdom interactions and expose its potential role in disease outcomes. IMPORTANCE Streptococcus intermedius, an oral commensal bacterium, has been clinically observed in subgingival dental plaque, purulent infections, and cystic fibrosis lungs. In this study, we have (i) determined the crystal structure of the V and C regions of Pas; (ii) shown that its surface protein Pas adheres to fibrinogen, which could potentially ferry the microbe through the bloodstream from the oral cavity; (iii) characterized Pas's high-affinity adherence to lung alveolar protein Gp340 that could fixate the microbe on lung epithelial cells; and (iv) most importantly, shown that these surface proteins on the oral commensal S. intermedius enhance biofilms of known pathogens Candida albicans and Pseudomonas aeruginosa.


Asunto(s)
Antígenos Bacterianos/metabolismo , Pseudomonas aeruginosa/metabolismo , Streptococcus intermedius/metabolismo , Secuencia de Aminoácidos , Antígenos Bacterianos/química , Antígenos Bacterianos/genética , Proteínas Bacterianas , Calcio/metabolismo , Regulación Bacteriana de la Expresión Génica , Modelos Moleculares , Unión Proteica , Conformación Proteica , Pseudomonas aeruginosa/genética , Streptococcus intermedius/genética
10.
Neurobiol Dis ; 158: 105470, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34371143

RESUMEN

Mitochondrial superoxide (O2-) production is implicated in aging, neurodegenerative disease, and most recently epilepsy. Yet the specific contribution of neuronal O2- to these phenomena is unclear. Here, we selectively deleted superoxide dismutase-2 (SOD2) in neuronal basic helix-loop-helix transcription factor (NEX)-expressing cells restricting deletion to a subset of excitatory principle neurons primarily in the forebrain (cortex and hippocampus). This resulted in nSOD2 KO mice that lived into adulthood (2-3 months) with epilepsy, selective loss of neurons, metabolic rewiring and a marked mitohormetic gene response. Surprisingly, expression of an astrocytic gene, glial fibrillary acidic protein (GFAP) was significantly increased relative to WT. Further studies in rat primary neuron-glial cultures showed that increased mitochondrial O2-, specifically in neurons, was sufficient to upregulate GFAP. These results suggest that neuron-specific mitochondrial O2- is sufficient to drive a complex and catastrophic epileptic phenotype and highlights the ability of SOD2 to act in a cell-nonautonomous manner to influence an astrocytic response.


Asunto(s)
Astrocitos/patología , Epilepsia/patología , Trastornos del Metabolismo de la Glucosa/patología , Mitocondrias , Neuronas , Estrés Oxidativo , Animales , Conducta Animal , Electroencefalografía , Epilepsia/psicología , Proteína Ácida Fibrilar de la Glía/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Actividad Motora , Cultivo Primario de Células , Ratas , Superóxido Dismutasa/genética , Superóxidos/metabolismo
11.
J Pharmacol Exp Ther ; 377(1): 1-10, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33500265

RESUMEN

Oxidative stress plays a crucial role in the pathogenesis of Parkinson disease (PD), and one strategy for neuroprotective therapy for PD is to scavenge reactive species using a catalytic antioxidant. Previous studies in our laboratory revealed that pretreatment of lipophilic metalloporphyrins showed protective effects in a mouse PD model. In this study, we optimized the formulations of these metalloporphyrins to deliver them orally and tested their efficacy on disease outcomes in a second species after initiation of an insult (i.e., disease modification). In this study, a pharmaceutical formulation of two metalloporphyrin catalytic antioxidants, AEOL11207 and AEOL11114, was tested for oral drug delivery. Both compounds showed gastrointestinal absorption, achieved high plasma concentrations, and readily penetrated the blood-brain barrier after intravenous or oral delivery. AEOL11207 and AEOL11114 bioavailabilities were calculated to be 24% and 25%, respectively, at a dose of 10 mg/kg via the oral route. In addition, both compounds significantly attenuated 6-hydroxydopamine (6-OHDA)-induced neurotoxic damage, including dopamine depletion, cytokine production, and microglial activation in the striata; dopaminergic neuronal loss in the substantia nigra; oxidative/nitrative stress indices (glutathione disulfide and 3-nitrotyrosine) in the ventral midbrain; and rotation behavioral abnormality in rats. These results indicate that AEOL11207 and AEOL11114 are orally active metalloporphyrins and protect against 6-OHDA neurotoxicity 1-3 days postlesioning, suggesting disease-modifying properties and translational potential for PD. SIGNIFICANCE STATEMENT: Two catalytic antioxidants showed gastrointestinal absorption, achieved high plasma concentrations, and readily penetrated the blood-brain barrier. Both compounds significantly attenuated dopamine depletion, cytokine production, microglial activation, dopaminergic neuronal loss, oxidative/nitrative stress indices, and behavioral abnormality in a Parkinson disease rat model. The results suggest that both metalloporphyrins possess disease-modifying properties that may be useful in treating Parkinson disease.


Asunto(s)
Antioxidantes/farmacocinética , Metaloporfirinas/farmacocinética , Fármacos Neuroprotectores/farmacocinética , Trastornos Parkinsonianos/tratamiento farmacológico , Administración Oral , Animales , Antioxidantes/administración & dosificación , Antioxidantes/uso terapéutico , Barrera Hematoencefálica/metabolismo , Masculino , Metaloporfirinas/administración & dosificación , Metaloporfirinas/uso terapéutico , Fármacos Neuroprotectores/administración & dosificación , Fármacos Neuroprotectores/uso terapéutico , Ratas , Ratas Sprague-Dawley , Distribución Tisular
12.
Ecol Appl ; 31(6): e02347, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34181285

RESUMEN

Over the past three decades, the Harvard Forest Summer Research Program in Ecology (HF-SRPE) has been at the forefront of expanding the ecological tent for minoritized or otherwise marginalized students. By broadening the definition of ecology to include fields such as data science, software engineering, and remote sensing, we attract a broader range of students, including those who may not prioritize field experiences or who may feel unsafe working in rural or urban field sites. We also work towards a more resilient society in which minoritized or marginalized students can work safely, in part by building teams of students and mentors. Teams collaborate on projects that require a diversity of approaches and create opportunities for students and mentors alike to support one another and share leadership. Finally, HF-SRPE promotes an expanded view of what it means to become an ecologist. We value and support diverse career paths for ecologists to work in all parts of society, to diversify the face of ecology, and to bring different perspectives together to ensure innovations in environmental problem solving for our planet.


Asunto(s)
Mentores , Estudiantes , Humanos
13.
Neurobiol Dis ; 133: 104457, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31028872

RESUMEN

The use of chemical warfare agents is an ongoing, significant threat to both civilians and military personnel worldwide. Nerve agents are by far the most formidable toxicants in terms of their lethality and toxicity. Nerve agents initiate neurotoxicity by the irreversible inhibition of acetylcholinesterase and resultant accumulation of acetylcholine in excitable tissues. The cholinergic toxidrome presents as miosis, lacrimation, diarrhea, fasciculations, seizures, respiratory arrest and coma. Current medical countermeasures can attenuate acute mortality and confer limited protection against secondary neuronal injury when given rapidly after exposure. However, there is an urgent need for the development of novel, add-on neuroprotective therapies to prevent mortality and long-term toxicity of nerve agents. Increasing evidence suggests that pathways other than direct acetylcholinesterase inhibition contribute to neurotoxicity and secondary neuronal injury. Among these, oxidative stress is emerging as a key therapeutic target for nerve agent toxicity. In this review, we discuss the rationale for targeting oxidative stress in nerve agent toxicity and highlight research investigating antioxidant therapy as a neuroprotective medical countermeasure to attenuate oxidative stress, neuroinflammation and neurodegeneration.


Asunto(s)
Antioxidantes/farmacología , Agentes Nerviosos/toxicidad , Fármacos Neuroprotectores/farmacología , Síndromes de Neurotoxicidad/tratamiento farmacológico , Estrés Oxidativo/efectos de los fármacos , Animales , Humanos
14.
N Engl J Med ; 377(10): 947-956, 2017 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-28877026

RESUMEN

BACKGROUND: The effect of a third dose of the measles-mumps-rubella (MMR) vaccine in stemming a mumps outbreak is unknown. During an outbreak among vaccinated students at the University of Iowa, health officials implemented a widespread MMR vaccine campaign. We evaluated the effectiveness of a third dose for outbreak control and assessed for waning immunity. METHODS: Of 20,496 university students who were enrolled during the 2015-2016 academic year, mumps was diagnosed in 259 students. We used Fisher's exact test to compare unadjusted attack rates according to dose status and years since receipt of the second MMR vaccine dose. We used multivariable time-dependent Cox regression models to evaluate vaccine effectiveness, according to dose status (three vs. two doses and two vs. no doses) after adjustment for the number of years since the second dose. RESULTS: Before the outbreak, 98.1% of the students had received at least two doses of MMR vaccine. During the outbreak, 4783 received a third dose. The attack rate was lower among the students who had received three doses than among those who had received two doses (6.7 vs. 14.5 cases per 1000 population, P<0.001). Students had more than nine times the risk of mumps if they had received the second MMR dose 13 years or more before the outbreak. At 28 days after vaccination, receipt of the third vaccine dose was associated with a 78.1% lower risk of mumps than receipt of a second dose (adjusted hazard ratio, 0.22; 95% confidence interval, 0.12 to 0.39). The vaccine effectiveness of two doses versus no doses was lower among students with more distant receipt of the second vaccine dose. CONCLUSIONS: Students who had received a third dose of MMR vaccine had a lower risk of mumps than did those who had received two doses, after adjustment for the number of years since the second dose. Students who had received a second dose of MMR vaccine 13 years or more before the outbreak had an increased risk of mumps. These findings suggest that the campaign to administer a third dose of MMR vaccine improved mumps outbreak control and that waning immunity probably contributed to propagation of the outbreak. (Funded by the Centers for Disease Control and Prevention.).


Asunto(s)
Brotes de Enfermedades/prevención & control , Inmunización Secundaria , Vacuna contra el Sarampión-Parotiditis-Rubéola/inmunología , Paperas/prevención & control , Adolescente , Femenino , Humanos , Iowa/epidemiología , Masculino , Vacuna contra el Sarampión-Parotiditis-Rubéola/administración & dosificación , Paperas/epidemiología , Paperas/inmunología , Modelos de Riesgos Proporcionales , Riesgo , Estudiantes , Universidades , Adulto Joven
15.
J Clin Microbiol ; 58(6)2020 05 26.
Artículo en Inglés | MEDLINE | ID: mdl-32238434

RESUMEN

Measurement of measles virus-specific IgG is used to assess presumptive evidence of immunity among immunocompetent individuals with uncertain immune or vaccination status. False-negative test results may lead to unnecessary quarantine and exclusion from activities such as employment, education, and travel or result in unnecessary revaccination. In contrast, false-positive results may fail to identify susceptible individuals and promote spread of disease by those who are exposed and unprotected. To better understand the performance characteristics of tests to detect measles IgG, we compared five widely used, commercially available measles IgG test platforms using a set of 223 well-characterized serum samples. Measles virus neutralizing antibodies were also measured by in vitro plaque reduction neutralization, the gold standard method, and compared to IgG test results. Discrepant results were observed for samples in the low-positive ranges of the most sensitive tests, but there was good agreement across platforms for IgG-negative sera and for samples with intermediate to high levels of IgG. False-negative test results occurred in approximately 11% of sera, which had low levels of neutralizing antibody.


Asunto(s)
Virus del Sarampión , Sarampión , Anticuerpos Antivirales , Ensayo de Inmunoadsorción Enzimática , Humanos , Inmunoensayo , Inmunoglobulina G , Sarampión/diagnóstico , Pruebas de Neutralización , Sensibilidad y Especificidad
16.
Brain ; 142(7): e39, 2019 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-31145451

RESUMEN

Epilepsy therapy is based on antiseizure drugs that treat the symptom, seizures, rather than the disease and are ineffective in up to 30% of patients. There are no treatments for modifying the disease-preventing seizure onset, reducing severity or improving prognosis. Among the potential molecular targets for attaining these unmet therapeutic needs, we focused on oxidative stress since it is a pathophysiological process commonly occurring in experimental epileptogenesis and observed in human epilepsy. Using a rat model of acquired epilepsy induced by electrical status epilepticus, we show that oxidative stress occurs in both neurons and astrocytes during epileptogenesis, as assessed by measuring biochemical and histological markers. This evidence was validated in the hippocampus of humans who died following status epilepticus. Oxidative stress was reduced in animals undergoing epileptogenesis by a transient treatment with N-acetylcysteine and sulforaphane, which act to increase glutathione levels through complementary mechanisms. These antioxidant drugs are already used in humans for other therapeutic indications. This drug combination transiently administered for 2 weeks during epileptogenesis inhibited oxidative stress more efficiently than either drug alone. The drug combination significantly delayed the onset of epilepsy, blocked disease progression between 2 and 5 months post-status epilepticus and drastically reduced the frequency of spontaneous seizures measured at 5 months without modifying the average seizure duration or the incidence of epilepsy in animals. Treatment also decreased hippocampal neuron loss and rescued cognitive deficits. Oxidative stress during epileptogenesis was associated with de novo brain and blood generation of high mobility group box 1 (HMGB1), a neuroinflammatory molecule implicated in seizure mechanisms. Drug-induced reduction of oxidative stress prevented HMGB1 generation, thus highlighting a potential novel mechanism contributing to therapeutic effects. Our data show that targeting oxidative stress with clinically used drugs for a limited time window starting early after injury significantly improves long-term disease outcomes. This intervention may be considered for patients exposed to potential epileptogenic insults.


Asunto(s)
Acetilcisteína/farmacología , Epilepsia/prevención & control , Glutatión/metabolismo , Isotiocianatos/farmacología , Estrés Oxidativo/efectos de los fármacos , Animales , Astrocitos/metabolismo , Biomarcadores/metabolismo , Estudios de Casos y Controles , Recuento de Células , Disfunción Cognitiva/complicaciones , Disfunción Cognitiva/prevención & control , Modelos Animales de Enfermedad , Estimulación Eléctrica , Epilepsia/complicaciones , Proteína HMGB1/sangre , Hipocampo/metabolismo , Humanos , Masculino , Neuronas/metabolismo , Neuronas/patología , Ratas , Estado Epiléptico/complicaciones , Estado Epiléptico/metabolismo , Estado Epiléptico/prevención & control , Sulfóxidos
17.
J Public Health Manag Pract ; 26(2): 109-115, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-30789597

RESUMEN

CONTEXT: In response to numerous mumps outbreaks reported throughout the United States in 2016 and 2017, the Advisory Committee on Immunization Practices (ACIP) recommended a third dose of measles, mumps, and rubella (MMR) vaccine for groups of persons determined by public health authorities to be at increased risk for acquiring mumps because of an outbreak. OBJECTIVE: To provide guidance for health departments when implementing the ACIP recommendation. DESIGN: Draft guidance was developed by Centers for Disease Control and Prevention subject matter experts based on technical consultations with health departments and review of published and unpublished data regarding mumps outbreaks. The guidance was finalized based on input from experts from the ACIP Mumps Work Group and local and state epidemiologists through the Council of State and Territorial Epidemiologists and the National Association of County and City Health Officials. RESULTS: We developed guidance to assist public health authorities when determining which groups are at increased risk for acquiring mumps and should receive a third dose of MMR vaccine. During outbreaks, public health authorities identify groups of persons with known or likely close contact exposure to a mumps patient. Then, evidence of transmission and likelihood of transmission in a group's setting can be used to determine whether these groups are at increased risk. Additional epidemiologic and implementation factors may also be considered. All persons in the group at increased risk for acquiring mumps should receive a dose of MMR vaccine, including those with unknown vaccination status or those who have evidence of presumptive immunity other than documented 2 doses of MMR vaccine; no additional dose is recommended for persons who had received 3 or more doses before the outbreak. CONCLUSION: This guidance provides a framework for public health authorities to use when considering a third dose of MMR in response to mumps outbreaks while maintaining flexibility to incorporate local factors related to individual outbreaks.


Asunto(s)
Centers for Disease Control and Prevention, U.S./tendencias , Vacuna contra el Sarampión-Parotiditis-Rubéola/administración & dosificación , Centers for Disease Control and Prevention, U.S./organización & administración , Brotes de Enfermedades/prevención & control , Relación Dosis-Respuesta a Droga , Guías como Asunto , Humanos , Esquemas de Inmunización , Vacuna contra el Sarampión-Parotiditis-Rubéola/uso terapéutico , Estados Unidos
18.
J Public Health Manag Pract ; 26(2): 101-108, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-30807465

RESUMEN

CONTEXT: During January 2016 to June 2017, US health departments (HDs) reported 150 mumps outbreaks. Most occurred among populations with high 2-dose measles, mumps, and rubella (MMR) vaccine coverage, prompting the Advisory Committee on Immunization Practices to examine the evidence for use of a third dose of MMR vaccine. OBJECTIVE: To evaluate HD experiences with mumps outbreak control and use of a third MMR dose during outbreaks. DESIGN: An online survey assessing mumps outbreak characteristics, outbreak response measures, challenges, and lessons learned from previous outbreaks was distributed to all 81 Council of State and Territorial Epidemiologists member HDs in August 2017. RESULTS: Sixty-one (75%) HDs responded; 46 (75%) had experience with ≥1 mumps outbreak(s) during January 2016 to August 2017. Twenty (43%) HDs recommended a third or outbreak MMR dose during mumps outbreaks; of these, 19 completed the section on use of a third dose and 8 (40%) rated the intervention "somewhat effective" or better. Health departments that used a third/outbreak dose suggested implementing the recommendation early and to a targeted group. Forty-three (73%) HDs reported having a policy for excluding persons without presumptive immunity from outbreak settings; of these, 37 (86%) had some degree of legal authority to implement this policy. Exclusion compliance improved with the use of personalized notification letters, focus groups of excluded persons and the community, and standardized messaging. Other outbreak control measures included cohorting of exposed or susceptible persons, mobile vaccination clinics and home visits, contact monitoring via text messaging, and facilitating student isolation with meal delivery and excused class absences. CONCLUSIONS: Our study revealed heterogeneity across HDs' mumps outbreak responses but also identified common challenges that will inform future Centers for Disease Control and Prevention guidance. These results were considered in the October 2017 Advisory Committee on Immunization Practices recommendation for use of a third dose of MMR vaccine for persons at increased risk for mumps during an outbreak and in the development of Centers for Disease Control and Prevention guidance for HDs when applying the Advisory Committee on Immunization Practices recommendation.


Asunto(s)
Relación Dosis-Respuesta a Droga , Vacuna contra el Sarampión-Parotiditis-Rubéola/administración & dosificación , Paperas/prevención & control , Salud Pública/métodos , Comités Consultivos/organización & administración , Comités Consultivos/tendencias , Brotes de Enfermedades/prevención & control , Brotes de Enfermedades/estadística & datos numéricos , Política de Salud/tendencias , Humanos , Vacuna contra el Sarampión-Parotiditis-Rubéola/uso terapéutico , Paperas/tratamiento farmacológico , Paperas/epidemiología , Salud Pública/tendencias , Encuestas y Cuestionarios , Estados Unidos/epidemiología
19.
J Infect Dis ; 219(10): 1616-1623, 2019 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-30535027

RESUMEN

BACKGROUND: Although measles was declared eliminated from the United States in 2000, measles cases and outbreaks continue to occur, resulting from importations of the disease from countries where it remains endemic. METHODS: We describe the epidemiology of international importations of measles virus into the United States during the postelimination era. RESULTS: From 2001 to 2016, 553 imported measles cases were reported to the Centers for Disease Control and Prevention. A median of 28 importations occurred each year (range: 18-80). The median age of imported case-patients was 18 years (range: 3 months-75 years); 87% were unvaccinated or had an unknown vaccination status. US residents (as opposed to foreign visitors) accounted for 62% of imported measles cases. Overall, 62% of all imported case-patients reported travel to countries in the Western Pacific and European Regions of the World Health Organization during their exposure periods. The number of measles importations from specific countries was related to the incidence of measles in and the volume of travel to and from the source country. CONCLUSIONS: Our findings emphasize the importance of measles vaccination of US residents aged ≥6 months before international travel according to the Advisory Committee on Immunization Practices recommendations and supporting global measles elimination efforts.


Asunto(s)
Enfermedades Transmisibles Importadas/epidemiología , Brotes de Enfermedades/estadística & datos numéricos , Virus del Sarampión , Sarampión/epidemiología , Adolescente , Adulto , Anciano , Niño , Preescolar , Enfermedades Transmisibles Importadas/prevención & control , Femenino , Humanos , Inmunización/estadística & datos numéricos , Lactante , Masculino , Sarampión/prevención & control , Vacuna Antisarampión , Persona de Mediana Edad , Viaje/estadística & datos numéricos , Estados Unidos/epidemiología , Adulto Joven
20.
Clin Infect Dis ; 68(10): 1684-1690, 2019 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-30204850

RESUMEN

BACKGROUND: Mumps is an acute viral illness that classically presents with parotitis. Although the United States experienced a 99% reduction in mumps cases following implementation of the 2-dose vaccination program in 1989, mumps has resurged in the past 10 years. METHODS: We assessed the epidemiological characteristics of mumps outbreaks with ≥20 cases reported in the United States electronically through the National Notifiable Diseases Surveillance System and from supplemental outbreak data through direct communications with jurisdictions from July 2010 through December 2015. Mumps cases were defined using the 2012 Council of State and Territorial Epidemiologists case definition. RESULTS: Twenty-three outbreaks with 20-485 cases per outbreak were reported in 18 jurisdictions. The duration of outbreaks ranged from 1.5 to 8.5 months (median, 3 months). All outbreaks involved close-contact settings; 18 (78%) involved universities, 16 (70%) occurred primarily among young adults (median age, 18-24 years), and 9 (39%) occurred in highly vaccinated populations (2-dose measles-mumps-rubella vaccine coverage ≥85%). CONCLUSIONS: During 2010-2015, multiple mumps outbreaks among highly vaccinated populations in close-contact settings occurred. Most cases occurred among vaccinated young adults, suggesting that waning immunity played a role. Further evaluation of risk factors associated with these outbreaks is warranted.


Asunto(s)
Brotes de Enfermedades/estadística & datos numéricos , Monitoreo Epidemiológico , Programas de Inmunización , Vacuna contra el Sarampión-Parotiditis-Rubéola/administración & dosificación , Paperas/epidemiología , Vacunación/estadística & datos numéricos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Humanos , Lactante , Persona de Mediana Edad , Paperas/transmisión , Investigación Cualitativa , Factores de Riesgo , Estudiantes/estadística & datos numéricos , Estados Unidos/epidemiología , Universidades , Adulto Joven
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