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1.
J Neuroinflammation ; 19(1): 200, 2022 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-35933420

RESUMEN

BACKGROUND: The close interaction and interdependence of astrocytes and neurons allows for the possibility that astrocyte dysfunction contributes to and amplifies neurodegenerative pathology. Molecular pathways that trigger reactive astrocytes may represent important targets to preserve normal homeostatic maintenance and modify disease progression. METHODS: Semaphorin 4D (SEMA4D) expression in the context of disease-associated neuropathology was assessed in postmortem brain sections of patients with Huntington's (HD) and Alzheimer's disease (AD), as well as in mouse models of HD (zQ175) and AD (CVN; APPSwDI/NOS2-/-) by immunohistochemistry. Effects of SEMA4D antibody blockade were assessed in purified astrocyte cultures and in the CVN mouse AD model. CVN mice were treated weekly from 26 to 38 weeks of age; thereafter mice underwent cognitive assessment and brains were collected for histopathology. RESULTS: We report here that SEMA4D is upregulated in neurons during progression of neurodegenerative diseases and is a trigger of reactive astrocytes. Evidence of reactive astrocytes in close proximity to neurons expressing SEMA4D is detected in brain sections of patients and mouse models of HD and AD. We further report that SEMA4D-blockade prevents characteristic loss of GABAergic synapses and restores spatial memory and learning in CVN mice, a disease model that appears to reproduce many features of AD-like pathology including neuroinflammation. In vitro mechanistic studies demonstrate that astrocytes express cognate receptors for SEMA4D and that ligand binding triggers morphological variations, and changes in expression of key membrane receptors and enzymes characteristic of reactive astrocytes. These changes include reductions in EAAT-2 glutamate transporter and glutamine synthetase, key enzymes in neurotransmitter recycling, as well as reduced GLUT-1 glucose and MCT-4 lactate transporters, that allow astrocytes to couple energy metabolism with synaptic activity. Antibody blockade of SEMA4D prevented these changes and reversed functional deficits in glucose uptake. CONCLUSIONS: Collectively, these results suggest that SEMA4D blockade may ameliorate disease pathology by preserving normal astrocyte function and reducing the negative consequences of reactive astrogliosis.


Asunto(s)
Enfermedad de Alzheimer , Antígenos CD/metabolismo , Astrocitos , Neuronas/metabolismo , Semaforinas/metabolismo , Enfermedad de Alzheimer/patología , Animales , Astrocitos/metabolismo , Encéfalo/metabolismo , Modelos Animales de Enfermedad , Humanos , Ratones
2.
BMC Health Serv Res ; 22(1): 201, 2022 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-35164749

RESUMEN

OBJECTIVES: Many payers and health care providers are either currently using or considering use of prior authorization schemes to redirect patient care away from hospital outpatient departments toward free-standing ambulatory surgical centers owing to the payment differential between these facilities. In this work we work with a medium size payer to develop and lay out a process for analysis of claims data that allows payers to conservatively estimate potential savings from such policies based on their specific case mix and provider network. STUDY DESIGN: We analyzed payment information for a medium-sized managed care organization to identify movable cases that can reduce costs, estimate potential savings, and recommend implementation policy alternatives. METHODS: We analyze payment data, including all professional and institutional fees over a 15-month period. A rules-based algorithm was developed to identify episodes of care with at least one alternate site for each episode, and potential savings from a site-of-service policy. RESULTS: Data on 64,884 episodes of care were identified as possible instances that could be subject to the policy. Of those, 7,679 were found to be attractive candidates for movement. Total projected savings was approximately $8.2 million, or over $1,000 per case. CONCLUSIONS: Instituting a site-of-service policy can produce meaningful savings for small and medium payers. Tailoring the policy to the specific patient and provider population can increase the efficacy of such policies in comparison to policies previously established by other payers.


Asunto(s)
Instituciones de Atención Ambulatoria , Autorización Previa , Costos y Análisis de Costo , Personal de Salud , Humanos , Derivación y Consulta , Estados Unidos
3.
J Appl Toxicol ; 41(9): 1380-1389, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33569802

RESUMEN

Glia cells provide supportive functions to the central nervous system and can be compromised by environmental contaminants. The primary objective of this study was to characterize the effects of in vitro exposure to perfluorooctanoic acid, a persistent environmental contaminant and/or monocrotophos (MCP), a neurotoxic organophosphate that is rapidly metabolized, to astroglia SVG p12 cells. The endpoints evaluated include cell viability, intracellular glutamate levels as a marker of astrocyte homeostasis function, differential gene expression for selected proteins, which include inflammatory markers (tachykinin), astrocytosis (nestin), S100B, and metabolism enzymes (CYP1A1). The results from cell viability revealed significant differences from the controls at some of the concentrations tested. Also, intracellular glutamate levels were elevated at the 10-µM concentration for perfluorooctanoic acid (PFOA) as well as the 10-µM PFOA/5-µM MCP concentration. Gene expression results at 80-µM PFOA concentration revealed a significant increase in the expression of S100B, tachykinin and CYP1A1. A combination of 10-µM PFOA/20-µM MCP caused a significant decrease in the expression of tachykinin. Gene expression for MCP exposures produced a decrease at the 20-µM MCP concentration. Immunofluorescence results indicated an increase in nestin protein expression for the 20-µM concentration of MCP, which contradicted the gene expression at the same concentration tested. The results indicate that toxicity to glia cells can compromise critical glia functions and could be implicated in neurodegenerative diseases.


Asunto(s)
Astrocitos/efectos de los fármacos , Caprilatos/toxicidad , Fluorocarburos/toxicidad , Insecticidas/toxicidad , Monocrotofos/toxicidad , Animales , Línea Celular , Supervivencia Celular/efectos de los fármacos , Citocromo P-450 CYP1A1/biosíntesis , Contaminantes Ambientales/toxicidad , Femenino , Expresión Génica/efectos de los fármacos , Ácido Glutámico/metabolismo , Homeostasis/efectos de los fármacos , Humanos , Nestina/biosíntesis , Células PC12 , Embarazo , Ratas , Subunidad beta de la Proteína de Unión al Calcio S100/biosíntesis , Taquicininas/biosíntesis
4.
Gen Comp Endocrinol ; 285: 113265, 2020 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-31473183

RESUMEN

Developing baseline concentrations of serotonin in healthy white-tailed deer will allow for the development of a biomarker using non-invasive sample tissues in sick animals, for example, non-clinical cases of chronic wasting disease. It will also allow some further insight into whether the use of antibiotics as growth promoters (AGP), such as chlortetracycline, is affecting serotonin concentrations in white-tailed deer. Florfenicol and tulathromycin impacts on serotonin concentration changes were also investigated. An analytical method for the detection and confirmation of serotonin, 5-hydroxytryptamine (5-HT), in white-tailed deer tissues was developed and validated. Serum and urine samples were extracted with acetonitrile. Liquid chromatography separation was attained on a Phenomenex C18 column with a Security Guard ULTRA guard column with gradient elution using a mobile phase of 0.1% formic acid in water and 0.1% formic acid in acetonitrile. This methodology was applied to baseline (control), chlortetracycline (CTC) treated, florfenicol treated and tulathromycin treated white-tailed deer serum and urine samples.


Asunto(s)
Antibacterianos/farmacología , Ciervos/metabolismo , Serotonina/metabolismo , Animales , Ciervos/sangre , Ciervos/orina , Disacáridos/farmacología , Femenino , Microbioma Gastrointestinal/efectos de los fármacos , Compuestos Heterocíclicos/farmacología , Límite de Detección , Masculino , Estándares de Referencia , Serotonina/sangre , Serotonina/orina , Tianfenicol/análogos & derivados , Tianfenicol/farmacología
5.
Ecotoxicol Environ Saf ; 154: 245-254, 2018 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-29476974

RESUMEN

We examined gonads and thyroid glands of Gulf killifish (Fundulus grandis) 1yr after the Deepwater Horizon oil spill. F. grandis were trapped from two impacted sites in Barataria Bay (Bayou St. Denis, Bay Jimmy) and an un-impacted site in East Texas (Sabine Pass). The greatest number of F. grandis were collected at Sabine Pass. F. grandis collected at Bayou St. Denis were smaller and had smaller Fulton condition factor scores than fish collected at Sabine Pass. Sex ratios were biased roughly 2:1 in favor of females at Sabine Pass and Bayou St. Denis. Gonad-somatic index (GSI) in males from Sabine Pass was double that of fish from Bay Jimmy while germinal epithelium thickness of the testes was 2.7 fold smaller in males from the impacted site. GSI and oocyte diameters in females from Bayou St. Denis were significantly smaller than females from Bay Jimmy or the reference site. There were no differences in thyroid follicle cell height. While total polyaromatic hydrocarbons at the impacted sites were no different from the reference site, the impacted sites did have greater concentrations of benzo[a]pyrene in sediment pore water. The finding of smaller GSI and testicular germinal epithelium in males from an impacted site suggest that exposure to a combination of oil and dispersants may adversely impact testicular function.


Asunto(s)
Monitoreo del Ambiente/métodos , Fundulidae/crecimiento & desarrollo , Gónadas/efectos de los fármacos , Contaminación por Petróleo/efectos adversos , Glándula Tiroides/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Animales , Bahías/química , Femenino , Gónadas/patología , Golfo de México , Louisiana , Masculino , Contaminación por Petróleo/análisis , Glándula Tiroides/patología , Contaminantes Químicos del Agua/análisis
6.
Neurobiol Dis ; 76: 46-56, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25662335

RESUMEN

Huntington disease (HD) is an inherited, fatal neurodegenerative disease with no disease-modifying therapy currently available. In addition to characteristic motor deficits and atrophy of the caudate nucleus, signature hallmarks of HD include behavioral abnormalities, immune activation, and cortical and white matter loss. The identification and validation of novel therapeutic targets that contribute to these degenerative cellular processes may lead to new interventions that slow or even halt the course of this insidious disease. Semaphorin 4D (SEMA4D) is a transmembrane signaling molecule that modulates a variety of processes central to neuroinflammation and neurodegeneration including glial cell activation, neuronal growth cone collapse and apoptosis of neural precursors, as well as inhibition of oligodendrocyte migration, differentiation and process formation. Therefore, inhibition of SEMA4D signaling could reduce CNS inflammation, increase neuronal outgrowth and enhance oligodendrocyte maturation, which may be of therapeutic benefit in the treatment of several neurodegenerative diseases, including HD. To that end, we evaluated the preclinical therapeutic efficacy of an anti-SEMA4D monoclonal antibody, which prevents the interaction between SEMA4D and its receptors, in the YAC128 transgenic HD mouse model. Anti-SEMA4D treatment ameliorated neuropathological signatures, including striatal atrophy, cortical atrophy, and corpus callosum atrophy and prevented testicular degeneration in YAC128 mice. In parallel, a subset of behavioral symptoms was improved in anti-SEMA4D treated YAC128 mice, including reduced anxiety-like behavior and rescue of cognitive deficits. There was, however, no discernible effect on motor deficits. The preservation of brain gray and white matter and improvement in behavioral measures in YAC128 mice treated with anti-SEMA4D suggest that this approach could represent a viable therapeutic strategy for the treatment of HD. Importantly, this work provides in vivo demonstration that inhibition of pathways initiated by SEMA4D constitutes a novel approach to moderation of neurodegeneration.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Antígenos CD/inmunología , Enfermedad de Huntington/terapia , Semaforinas/inmunología , Animales , Anticuerpos Monoclonales/administración & dosificación , Encéfalo/metabolismo , Encéfalo/patología , Trastornos del Conocimiento/etiología , Trastornos del Conocimiento/terapia , Modelos Animales de Enfermedad , Enfermedad de Huntington/complicaciones , Inmunoterapia , Ratones , Ratones Transgénicos , Actividad Motora/efectos de los fármacos , Transducción de Señal/efectos de los fármacos
7.
Neurobiol Dis ; 73: 254-68, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25461192

RESUMEN

Multiple sclerosis (MS) is a chronic neuroinflammatory disease characterized by immune cell infiltration of CNS, blood-brain barrier (BBB) breakdown, localized myelin destruction, and progressive neuronal degeneration. There exists a significant need to identify novel therapeutic targets and strategies that effectively and safely disrupt and even reverse disease pathophysiology. Signaling cascades initiated by semaphorin 4D (SEMA4D) induce glial activation, neuronal process collapse, inhibit migration and differentiation of oligodendrocyte precursor cells (OPCs), and disrupt endothelial tight junctions forming the BBB. To target SEMA4D, we generated a monoclonal antibody that recognizes mouse, rat, monkey and human SEMA4D with high affinity and blocks interaction between SEMA4D and its cognate receptors. In vitro, anti-SEMA4D reverses the inhibitory effects of recombinant SEMA4D on OPC survival and differentiation. In vivo, anti-SEMA4D significantly attenuates experimental autoimmune encephalomyelitis in multiple rodent models by preserving BBB integrity and axonal myelination and can be shown to promote migration of OPC to the site of lesions and improve myelin status following chemically-induced demyelination. Our study underscores SEMA4D as a key factor in CNS disease and supports the further development of antibody-based inhibition of SEMA4D as a novel therapeutic strategy for MS and other neurologic diseases with evidence of demyelination and/or compromise to the neurovascular unit.


Asunto(s)
Barrera Hematoencefálica/metabolismo , Encefalomielitis Autoinmune Experimental/metabolismo , Oligodendroglía/metabolismo , Semaforinas/metabolismo , Animales , Anticuerpos Monoclonales , Encefalomielitis Autoinmune Experimental/tratamiento farmacológico , Encefalomielitis Autoinmune Experimental/inmunología , Femenino , Masculino , Ratones , Ratones Endogámicos C57BL , Ratas , Ratas Sprague-Dawley , Semaforinas/antagonistas & inhibidores , Semaforinas/inmunología
8.
BMC Immunol ; 16: 6, 2015 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-25879435

RESUMEN

BACKGROUND: Homeostatic B Cell-Attracting chemokine 1 (BCA-1) otherwise known as CXCL13 is constitutively expressed in secondary lymphoid organs by follicular dendritic cells (FDC) and macrophages. It is the only known ligand for the CXCR5 receptor, which is expressed on mature B cells, follicular helper T cells (Tfh), Th17 cells and regulatory T (Treg) cells. Aberrant expression of CXCL13 within ectopic germinal centers has been linked to the development of autoimmune disorders (e.g. Rheumatoid Arthritis, Multiple Sclerosis, Systemic Lupus Erythematosis). We, therefore, hypothesized that antibody-mediated disruption of the CXCL13 signaling pathway would interfere with the formation of ectopic lymphoid follicles in the target organs and inhibit autoimmune disease progression. This work describes pre-clinical development of human anti-CXCL13 antibody MAb 5261 and includes therapeutic efficacy data of its mouse counterpart in murine models of autoimmunity. RESULTS: We developed a human IgG1 monoclonal antibody, MAb 5261 that specifically binds to human, rodent and primate CXCL13 with an affinity of approximately 5 nM and is capable of neutralizing the activity of CXCL13 from these various species in in vitro functional assays. For in vivo studies we have engineered a chimeric antibody to contain the same human heavy and light chain variable genes along with mouse constant regions. Treatment with this antibody led to a reduction in the number of germinal centers in mice immunized with 4-Hydroxy-3-nitrophenylacetyl hapten conjugated to Keyhole Limpet Hemocyanin (NP-KLH) and, in adoptive transfer studies, interfered with the trafficking of B cells to the B cell areas of mouse spleen. Furthermore, this mouse anti-CXCL13 antibody demonstrated efficacy in a mouse model of Rheumatoid arthritis (Collagen-Induced Arthritis (CIA)) and Th17-mediated murine model of Multiple Sclerosis (passively-induced Experimental Autoimmune Encephalomyelitis (EAE)). CONCLUSIONS: We developed a novel therapeutic antibody targeting CXCL13-mediated signaling pathway for the treatment of autoimmune disorders.


Asunto(s)
Anticuerpos Bloqueadores/administración & dosificación , Artritis Experimental/terapia , Artritis Reumatoide/terapia , Linfocitos B/efectos de los fármacos , Quimiocina CXCL13/metabolismo , Células Dendríticas Foliculares/efectos de los fármacos , Encefalomielitis Autoinmune Experimental/terapia , Inmunoglobulina G/administración & dosificación , Inmunoterapia/métodos , Macrófagos/efectos de los fármacos , Esclerosis Múltiple/terapia , Proteínas Recombinantes de Fusión/administración & dosificación , Células Th17/efectos de los fármacos , Animales , Artritis Experimental/inmunología , Artritis Reumatoide/inmunología , Linfocitos B/inmunología , Movimiento Celular/efectos de los fármacos , Células Cultivadas , Quimiocina CXCL13/inmunología , Células Dendríticas Foliculares/inmunología , Modelos Animales de Enfermedad , Encefalomielitis Autoinmune Experimental/inmunología , Femenino , Ingeniería Genética , Centro Germinal/efectos de los fármacos , Hemocianinas/química , Hemocianinas/inmunología , Humanos , Macrófagos/inmunología , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Endogámicos DBA , Esclerosis Múltiple/inmunología , Nitrofenoles/química , Nitrofenoles/inmunología , Fenilacetatos/química , Fenilacetatos/inmunología , Receptores CXCR5/metabolismo , Transducción de Señal/efectos de los fármacos , Células Th17/inmunología
9.
Gen Comp Endocrinol ; 219: 16-23, 2015 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-25448256

RESUMEN

We investigated stage-dependent changes in sensitivity of the thyroid gland to perchlorate during development of African clawed frog tadpoles (Xenopus laevis) in relation to non-thyroidal iodide transporting tissues. Perchlorate-induced increases in thyroid follicle cell size and colloid depletion were blunted when exposures began at Nieuwkoop-Faber (NF) stage 55 compared to when exposures began at NF stages 49 or 1-10. To determine if the development of other iodide transporting tissues may contribute to this difference we first examined which tissues expressed transcripts for the sodium dependent iodide symporter (NIS). RT-PCR analysis revealed that NIS was expressed in stomach and small intestine in addition to the thyroid gland of X. laevis tadpoles. NIS mRNA was not detected in lung, kidney, skin, gill, muscle, heart or liver. Perchlorate sensitive (125)I uptake was found in stomach, lung, kidney, gill, and small intestine but not muscle, liver, or heart. Perchlorate-sensitive (125)I uptake by stomach was 6-10 times greater than in any other non-thyroidal tissue in tadpoles. While NF stage 49 tadpoles exhibited perchlorate-sensitive uptake in stomach it was roughly 4-fold less than that observed in NF stage 55 tadpoles. Although abundance of NIS gene transcripts was greater in stomachs from NF stage 55 compared to NF stage 49 tadpoles this difference was not statistically significant. We conclude that gastric iodide uptake increases between NF stages 49 and 55, possibly due to post-translational changes in NIS glycosylation or trafficking within gastric mucosal cells. These developmental changes in gastric NIS gene expression may affect iodide availability to the thyroid gland.


Asunto(s)
Larva/metabolismo , Metamorfosis Biológica/genética , Percloratos/metabolismo , Simportadores/genética , Glándula Tiroides/metabolismo , Xenopus laevis/metabolismo , Animales , Femenino , Masculino
10.
Gen Comp Endocrinol ; 188: 204-11, 2013 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-23583471

RESUMEN

Previous work indicates that CRF administration inhibits visually guided feeding in amphibians. We used the African clawed frog Xenopus laevis to examine the hypothesis that CRF acts as a neurotransmitter in the optic tectum, the major brain area integrating the visual and premotor pathways regulating visually guided feeding in anurans. Reverse transcriptase PCR revealed that cells in the optic tectum express mRNA for CRF and the CRF R1 receptor but not the CRF R2 receptor. Radioligand binding studies indicated that specific binding of [(125)I]-Tyr-oCRF to tectal cell membranes can be displaced by the CRF R1 antagonists antalarmin or NBI-27914. CRF increased the expression of mRNA encoding regulator of G-protein signaling 2 (rgs2) in tectal explants and this effect was blocked by antalarmin. CRF had no effect on basal glutamate or gamma-aminobutyric acid (GABA) secretion but inhibited secretion of norepinephrine from tectal explants, an effect that completely blocked by antalarmin. Using a homologous radioimmunoassay we determined that CRF release from tectal explants in vitro was potassium- and calcium-dependent. Basal and depolarization-induced CRF secretion was greater from optic tectum than hypothalamus/thalamus, telencephalon, or brainstem. We concluded that the optic tectum possesses a CRF signaling system that may be involved in modulating communication between sensory and motor pathways involved in food intake.


Asunto(s)
Colículos Superiores/metabolismo , Animales , Anuros/metabolismo , Apetito/efectos de los fármacos , Ingestión de Alimentos/efectos de los fármacos , Pirimidinas/farmacología , Pirroles/farmacología , ARN Mensajero/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Transducción de Señal/efectos de los fármacos , Xenopus laevis/metabolismo
11.
Healthcare (Basel) ; 11(23)2023 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-38063621

RESUMEN

BACKGROUND: Rape scholarship in West Africa is growing, but studies often utilize Westernized approaches. A 2018 study using a randomized survey design assessing rape among Liberian girls incorporated modified survey design methods to improve ethical data collection relevant to the cultural and contextual contexts. This article presents the findings of a thorough review of rape scholarship and design methods. METHODS: Based on a qualitative analysis of field notes by the research team, we present lessons learned and best practices identified in the planning, pilot-testing, and implementation phases of the 2018 Liberian study. RESULTS: This study helps inform innovative design methods striving to (1) avoid using obtrusively graphic language or labels prevalent in westernized studies, (2) authentically collaborate with African experts to adapt strategies to be culturally appropriate and contextually relevant, and (3) create respectfully transparent interactions with respondents and communities. Extensive research preparation and inclusive regional expertise inform compassionate methodological techniques, yielding improved Afro-centric participant experience, low participant attrition, and quality data use in policymaking. (4) Conclusions: This article offers innovative design methods to study rape, placing context, culture, and participants at the heart. Authentic collaboration with national-level experts is vital for conducting more reliable and ethical field research in the African region.

12.
Nat Commun ; 14(1): 1770, 2023 03 30.
Artículo en Inglés | MEDLINE | ID: mdl-36997531

RESUMEN

Directed evolution in bacterial or yeast display systems has been successfully used to improve stability and expression of G protein-coupled receptors for structural and biophysical studies. Yet, several receptors cannot be tackled in microbial systems due to their complex molecular composition or unfavorable ligand properties. Here, we report an approach to evolve G protein-coupled receptors in mammalian cells. To achieve clonality and uniform expression, we develop a viral transduction system based on Vaccinia virus. By rational design of synthetic DNA libraries, we first evolve neurotensin receptor 1 for high stability and expression. Second, we demonstrate that receptors with complex molecular architectures and large ligands, such as the parathyroid hormone 1 receptor, can be readily evolved. Importantly, functional receptor properties can now be evolved in the presence of the mammalian signaling environment, resulting in receptor variants exhibiting increased allosteric coupling between the ligand binding site and the G protein interface. Our approach thus provides insights into the intricate molecular interplay required for GPCR activation.


Asunto(s)
Vaccinia , Animales , Ligandos , Virus Vaccinia/genética , Virus Vaccinia/metabolismo , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Transducción de Señal/genética , Mamíferos/metabolismo
13.
MAbs ; 15(1): 2249947, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37635331

RESUMEN

Antibody discovery against complex antigens is limited by the availability of a reproducible pure source of concentrated properly folded antigen. We have developed a technology to enable direct incorporation of membrane proteins such as GPCRs and into the membrane of poxvirus. The protein of interest is correctly folded and expressed in the cell-derived viral membrane and does not require any detergents or refolding before downstream use. The poxvirus is selective in which proteins are incorporated into the viral membrane, making the antigen poxvirus an antigenically cleaner target for in vitro panning. Antigen-expressing virus can be readily purified at scale and used for antibody selection using any in vitro display platform.


Asunto(s)
Antígenos , Biblioteca de Péptidos , Anticuerpos , Proteínas de la Membrana , Membrana Celular
14.
Malar J ; 11: 140, 2012 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-22545573

RESUMEN

BACKGROUND: Artemisinin-based combination therapy (ACT) has been promoted as a means to reduce malaria transmission due to their ability to kill both asexual blood stages of malaria parasites, which sustain infections over long periods and the immature derived sexual stages responsible for infecting mosquitoes and onward transmission. Early studies reported a temporal association between ACT introduction and reduced malaria transmission in a number of ecological settings. However, these reports have come from areas with low to moderate malaria transmission, been confounded by the presence of other interventions or environmental changes that may have reduced malaria transmission, and have not included a comparison group without ACT. This report presents results from the first large-scale observational study to assess the impact of case management with ACT on population-level measures of malaria endemicity in an area with intense transmission where the benefits of effective infection clearance might be compromised by frequent and repeated re-infection. METHODS: A pre-post observational study with a non-randomized comparison group was conducted at two sites in Tanzania. Both sites used sulphadoxine-pyrimethamine (SP) monotherapy as a first-line anti-malarial from mid-2001 through 2002. In 2003, the ACT, artesunate (AS) co-administered with SP (AS + SP), was introduced in all fixed health facilities in the intervention site, including both public and registered non-governmental facilities. Population-level prevalence of Plasmodium falciparum asexual parasitaemia and gametocytaemia were assessed using light microscopy from samples collected during representative household surveys in 2001, 2002, 2004, 2005 and 2006. FINDINGS: Among 37,309 observations included in the analysis, annual asexual parasitaemia prevalence in persons of all ages ranged from 11% to 28% and gametocytaemia prevalence ranged from <1% to 2% between the two sites and across the five survey years. A multivariable logistic regression model was fitted to adjust for age, socioeconomic status, bed net use and rainfall. In the presence of consistently high coverage and efficacy of SP monotherapy and AS + SP in the comparison and intervention areas, the introduction of ACT in the intervention site was associated with a modest reduction in the adjusted asexual parasitaemia prevalence of 5 percentage-points or 23% (p < 0.0001) relative to the comparison site. Gametocytaemia prevalence did not differ significantly (p = 0.30). INTERPRETATION: The introduction of ACT at fixed health facilities only modestly reduced asexual parasitaemia prevalence. ACT is effective for treatment of uncomplicated malaria and should have substantial public health impact on morbidity and mortality, but is unlikely to reduce malaria transmission substantially in much of sub-Saharan Africa where individuals are rapidly re-infected.


Asunto(s)
Antimaláricos/administración & dosificación , Artemisininas/administración & dosificación , Instituciones de Salud , Investigación sobre Servicios de Salud , Malaria Falciparum/tratamiento farmacológico , Malaria Falciparum/epidemiología , Adolescente , Adulto , Niño , Preescolar , Estudios Transversales , Combinación de Medicamentos , Quimioterapia Combinada/métodos , Humanos , Lactante , Malaria Falciparum/diagnóstico , Parasitemia/diagnóstico , Prevalencia , Pirimetamina/administración & dosificación , Sulfadoxina/administración & dosificación , Tanzanía/epidemiología , Resultado del Tratamiento , Adulto Joven
15.
Heliyon ; 8(2): e08990, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35243103

RESUMEN

In developing countries, fermentation is one of the traditional food processing methods for production of relatively safe and nutritious foods. Among many fermented foods in Ethiopia, "Shameta" is one of the locally produced and consumed cereal-based fermented porridge mainly used to support strength and recovery of lactating women after birth. However, even though the product is consumed for years, so far, the nutritional composition and bioactive compounds of the porridge not yet scientifically determined. This study aimed to determine the physicochemical properties, nutritional composition and bioactive compounds of "Shameta" commonly produced and consumed in Western part of the country. A total of 27 "Shameta" samples were collected from houses of lactating mothers residing in different districts of East Wollega zone. Results showed that, "Shameta" sample prepared from blend of maize and barely supplemented with faba bean results in crude protein content of 11.2 g/100g as compared with samples without faba bean, 6.8 g/100g. Samples supplemented with more proportion of rapeseed as oil source resulted in relatively higher crude fat content (12.2 g/100 g) as compared to other samples. From energy point of view, "Shameta" could provide about 85% of the extra energy needs of lactating mothers as compared to staple foods consumed in sample collection areas. It is also confirmed that, the product is a good source of iron and zinc, with the highest scores of 8.1 and 8.6 mg/100g in some samples, respectively, as compared to other mineral elements whose scores were much less than the daily recommended allowances. The average phytate and tannin contents were 0.79 and 0.18 mg/100g, respectively. Even though the Ca, Fe and Zn contents were below the recommended daily allowance, their bioavailability could not be hindered by phytate and tannin. Results also showed that samples have good antioxidant potential to minimize oxidative stresses. It could be deduced that as a sole food for the mothers, the product could not provide sufficient protein and some minerals to meet recommended daily allowance. However, to enhance the importance of the product, it is necessary to optimize the ingredient compositions and processing conditions to meet the nutrient demand of lactating mothers.

16.
J Hazard Mater Adv ; 7: 100128, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37520801

RESUMEN

Infections with coronaviruses remain a burden that is negatively affecting human life. The use of metal oxides to prevent and control the spread of severe acute respiratory syndrome coronavirus (SARS-CoV-2) has been widely studied. However, the use of metal oxides in masks to enhance the performances of barrier face coverings in trapping and neutralizing SARS-CoV-2 remained unexplored. In the present study, we explore the possibility of developing surface functional PVA/ZnO electrospun nanowebs to be used as a component of multilayer barrier face coverings. Polyvinyl alcohol (PVA) and zinc acetate (ZnA) nanowebs were electrospun as precursor samples. After calcination at 400 degrees centigrade under a controlled atmosphere of nitrogen gas, product nanowebs containing ZnO (PVA/ZnO) were obtained. The presence of ZnO was determined using an attenuated total reflectance Fourier Transform Infrared (FT-IR) spectrometer. This study inspired the possibility of developing surface-functional materials to produce enhanced performance masks against the spread of SARS-CoV-2.

17.
Nat Med ; 28(10): 2183-2193, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35941373

RESUMEN

SIGNAL is a multicenter, randomized, double-blind, placebo-controlled phase 2 study (no. NCT02481674) established to evaluate pepinemab, a semaphorin 4D (SEMA4D)-blocking antibody, for treatment of Huntington's disease (HD). The trial enrolled a total of 265 HD gene expansion carriers with either early manifest (EM, n = 179) or late prodromal (LP, n = 86) HD, randomized (1:1) to receive 18 monthly infusions of pepinemab (n = 91 EM, 41 LP) or placebo (n = 88 EM, 45 LP). Pepinemab was generally well tolerated, with a relatively low frequency of serious treatment-emergent adverse events of 5% with pepinemab compared to 9% with placebo, including both EM and LP participants. Coprimary efficacy outcome measures consisted of assessments within the EM cohort of (1) a two-item HD cognitive assessment family comprising one-touch stockings of Cambridge (OTS) and paced tapping (PTAP) and (2) clinical global impression of change (CGIC). The differences between pepinemab and placebo in mean change (95% confidence interval) from baseline at month 17 for OTS were -1.98 (-4.00, 0.05) (one-sided P = 0.028), and for PTAP 1.43 (-0.37, 3.23) (one-sided P = 0.06). Similarly, because a significant treatment effect was not observed for CGIC, the coprimary endpoint, the study did not meet its prespecified primary outcomes. Nevertheless, a number of other positive outcomes and post hoc subgroup analyses-including additional cognitive measures and volumetric magnetic resonance imaging and fluorodeoxyglucose-positron-emission tomography imaging assessments-provide rationale and direction for the design of a phase 3 study and encourage the continued development of pepinemab in patients diagnosed with EM HD.


Asunto(s)
Antineoplásicos , Enfermedad de Huntington , Semaforinas , Humanos , Anticuerpos Monoclonales/uso terapéutico , Antígenos CD , Antineoplásicos/uso terapéutico , Método Doble Ciego , Enfermedad de Huntington/tratamiento farmacológico , Enfermedad de Huntington/genética , Semaforinas/genética , Semaforinas/uso terapéutico , Resultado del Tratamiento
18.
Ecotoxicol Environ Saf ; 74(4): 924-8, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21257201

RESUMEN

Chronic aqueous exposures were conducted using bullfrog (Rana catesbeiana) tadpoles (8 d old) exposed to TNT (0-4 mg/L), 2,4-DNT (0-4 mg/L), and 2,6-DNT (0-8 mg/L) for 90 d. Survival of tadpoles examined using Cox proportional hazard models was reduced at all concentrations tested. Percent of abnormal swimming and other morphological abnormalities after sublethal exposure to TNT, 2,4-DNT, and 2,6-DNT at 2 mg/L were also evaluated. The effects of TNT, 2,4-DNT, and 2,6-DNT on wet body mass, snout vent length (SVL), and developmental stage of surviving tadpoles were examined. Only 2,4-DNT did not have a significant effect on body mass or SVL, but all three compounds tested had significant effects on survival. Long-term continuous exposure to these compounds at concentrations of 0.25 mg/L could lead to significant changes in growth and survival of larval amphibians.


Asunto(s)
Dinitrobencenos/toxicidad , Rana catesbeiana/crecimiento & desarrollo , Trinitrotolueno/toxicidad , Contaminantes Químicos del Agua/toxicidad , Animales , Conducta Animal/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Sustancias Explosivas/toxicidad , Femenino , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Masculino , Rana catesbeiana/anomalías , Natación
19.
Neurotox Res ; 39(2): 533-541, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33175324

RESUMEN

Neurodegenerative diseases account for a significant portion of public health concerns particularly in the aging population. The dysfunction of interfilament proteins has been identified as a key event in the initiation of neurodegeneration and subsequent progression to neurodegenerative diseases. In addition, several studies have found associations between the dysfunction of interfilament proteins and exposure to environmental contaminants. Therefore, in this review, the role of interfilament proteins in neuronal cells, their connection to neurotoxicity from environmental contaminants, and finally the resulting neurodegeneration are discussed.


Asunto(s)
Citoplasma/metabolismo , Contaminantes Ambientales/toxicidad , Enfermedades Neurodegenerativas/metabolismo , Neuronas/metabolismo , Animales , Transporte Axonal , Humanos , Plasticidad Neuronal , Proteínas/metabolismo
20.
Clin Cancer Res ; 27(13): 3630-3640, 2021 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-33820783

RESUMEN

PURPOSE: The CLASSICAL-Lung clinical trial tested the combination of pepinemab, an IgG4 humanized mAb targeting semaphorin 4D, with the PD-L1 inhibitor avelumab to assess the effects of coupling increased T-cell infiltration and reversal of immune suppression via pepinemab with sustained T-cell activation via checkpoint inhibition. PATIENTS AND METHODS: This phase Ib/II, single-arm study was designed to evaluate the safety, tolerability, and efficacy of pepinemab in combination with avelumab in 62 patients with advanced non-small cell lung cancer (NSCLC), including immunotherapy-naïve (ION) patients and patients whose tumors progressed following anti-PD-1/L1 monotherapy (IOF). The main objectives were to evaluate safety/tolerability, establish a recommended phase 2 dose (RP2D), obtain a preliminary evaluation of antitumor activity, and investigate candidate biomarker activity. RESULTS: The combination was well tolerated with no major safety signals identified. Pepinemab, 10 mg/kg with avelumab, 10 mg/kg, every 2 weeks, was selected as the RP2D. Among 21 evaluable ION patients, 5 patients experienced partial responses (PR), 4 patients evidenced clinical benefit ≥1 year, and the disease control rate (DCR) was 81%. Notably, overall response rate with the combination therapy was higher than previously reported for single-agent avelumab in the PD-L1-negative/low population. Among 29 evaluable IOF patients, the combination resulted in a DCR of 59%, including 2 PR and 7 patients with durable clinical benefit of ≥23 weeks. Biomarker analysis of biopsies demonstrated increased CD8 T-cell density correlating with RECIST response criteria. CONCLUSIONS: The combination of pepinemab with avelumab was well tolerated in NSCLC and showed signs of antitumor activity in immunotherapy-resistant and PD-L1-negative/low tumors.


Asunto(s)
Anticuerpos Monoclonales Humanizados , Anticuerpos Monoclonales , Antineoplásicos Inmunológicos , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales Humanizados/administración & dosificación , Antineoplásicos Inmunológicos/administración & dosificación , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/patología , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Estadificación de Neoplasias
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