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1.
J Pharmacol Exp Ther ; 385(3): 214-221, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36997325

RESUMEN

Diabetic retinopathy (DR) is a leading cause of vision loss in working-age adults. Despite an established standard of care for advanced forms of DR, some patients continue to lose vision after treatment. This may be due to the development of diabetic macular ischemia (DMI), which has no approved treatment. Neuropilin-1 (Nrp-1) is a coreceptor with two ligand-binding domains, with semaphorin-3A (Sema3A) binding to the A-domain and vascular endothelial growth factor-A (VEGF-A) binding to the B-domain. Sema3A directs a subset of neuronal growth cones as well as blood vessel growth by repulsion; when bound to Nrp-1, VEGF-A mediates vascular permeability and angiogenesis. Modulating Nrp-1 could therefore address multiple complications arising from DR, such as diabetic macular edema (DME) and DMI. BI-Y is a monoclonal antibody that binds to the Nrp-1 A-domain, antagonizing the effects of the ligand Sema3A and inhibiting VEGF-A-induced vascular permeability. This series of in vitro and in vivo studies examined the binding kinetics of BI-Y to Nrp-1 with and without VEGF-A165, the effect of BI-Y on Sema3A-induced cytoskeletal collapse, the effect of BI-Y on VEGF- A165-induced angiogenesis, neovascularization, cell integrity loss and permeability, and retinal revascularization. The data show that BI-Y binds to Nrp-1 and inhibits Sema3A-induced cytoskeletal collapse in vitro, may enhance revascularization of ischemic areas in an oxygen-induced retinopathy mouse model, and prevents VEGF-A-induced retinal hyperpermeability in rats. However, BI-Y does not interfere with VEGF-A-dependent choroidal neovascularization. These results support further investigation of BI-Y as a potential treatment for DMI and DME. SIGNIFICANCE STATEMENT: Diabetic macular ischemia (DMI) is a complication of diabetic retinopathy (DR) with no approved pharmacological treatment. Diabetic macular edema (DME) commonly co-occurs with DMI in patients with DR. This series of preclinical studies in mouse and rat models shows that neuropilin-1 antagonist BI-Y may enhance the revascularization of ischemic areas and prevents vascular endothelial growth factor-A (VEGF-A)-induced retinal hyperpermeability without affecting VEGF-A-dependent choroidal neovascularization; thus, BI-Y may be of interest as a potential treatment for patients with DR.


Asunto(s)
Neovascularización Coroidal , Retinopatía Diabética , Edema Macular , Enfermedades de la Retina , Animales , Ratones , Ratas , Retinopatía Diabética/tratamiento farmacológico , Retinopatía Diabética/metabolismo , Ligandos , Edema Macular/tratamiento farmacológico , Edema Macular/metabolismo , Neuropilina-1/antagonistas & inhibidores , Neuropilina-1/metabolismo , Roedores/metabolismo , Semaforina-3A , Factor A de Crecimiento Endotelial Vascular/metabolismo
2.
Telecomm Policy ; 47(4): 102499, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36685614

RESUMEN

Having adequate access to the internet at home enhances quality-of-life for households and facilitates economic and social opportunities. Despite increased investment in response to the COVID-19 pandemic, millions of households in the rural United States still lack adequate access to high-speed internet. In this study, we evaluate a wireless broadband network deployed in Turney, a small, underserved rural community in northwest Missouri. In addition to collecting survey data before and after this internet intervention, we collected pre-treatment and post-treatment survey data from comparison communities to serve as a control group. Due to technical constraints, some of Turney's interested participants could not connect to the network, creating an additional comparison group. These comparisons suggest two primary findings, (1) changes in using the internet for employment, education, and health could not be directly attributed to the internet intervention, and (2) the internet intervention was associated with benefits stemming from the ability to use multiple devices at once. This study has implications for the design of future broadband evaluation studies, particularly those examining underserved rather than unserved communities. Recommendations for identifying appropriate outcome variables, executing recruitment strategies, and selecting the timing of surveys are made.

3.
Telecomm Policy ; 46(7): 102310, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35132293

RESUMEN

Amidst COVID-19-related stay-at-home orders, the economy moved largely online and broadband internet became more important than ever. This paper explores the relationship between broadband and employment rates during April and May 2020 in rural U.S. counties. We use two broadband dimensions: infrastructure availability rates and household adoption rates. We use a two-stage least squares approach to address endogeneity and control for socioeconomic, demographic, and pandemic-related factors. Results show broadband availability and wired broadband adoption both had significant, positive impacts on the employment rate. Our findings suggest both broadband adoption and availability may be associated with economic benefits in rural America.

4.
Exp Eye Res ; 205: 108486, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33571529

RESUMEN

Half-life extension strategies to reduce the intravitreal dosing frequency of biomolecules for the treatment of retinal neovascular diseases are attracting increasing interest. This study investigated ocular and systemic pharmacokinetics of the trivalent nanobody BI-X (with affinity to VEGF, Ang-2 and human albumin) in cynomolgus monkeys after intravitreal injection. BI-X concentrations were measured in serial samples of plasma, vitreous humor, aqueous humor and retina. Ocular pharmacokinetics of BI-X exhibited two phases. Initially up to 2-4 weeks after dosing, BI-X concentrations in vitreal, aqueous humor and retina declined with half-lives of around 3 days, which is comparable to macromolecules with a similar molecular weight. Thereafter, only vitreal concentrations were measurable, with a terminal half-life of 13.2 days, which is considerably longer than expected based on the BI-X molecular weight or hydrodynamic radius. It is hypothesized that binding of BI-X to low levels of intraocular albumin resulted in this half-life extension. BI-X was detectable in plasma up to 10 weeks post-dosing. Plasma pharmacokinetics of BI-X exhibited a similar biphasic disposition profile to the vitreous body, with a terminal half-life of 11.8 days, thus reflecting input kinetics from the eye. In conclusion, an important half-life extension principle based on vitreal albumin binding could be confirmed in a primate model, and the data obtained can potentially be translated to humans taking into account the differing vitreal albumin concentrations.


Asunto(s)
Inhibidores de la Angiogénesis/farmacocinética , Angiopoyetina 2/metabolismo , Albúmina Sérica Humana/farmacología , Factor A de Crecimiento Endotelial Vascular/metabolismo , Cuerpo Vítreo/metabolismo , Animales , Área Bajo la Curva , Sinergismo Farmacológico , Femenino , Semivida , Inyecciones Intravítreas , Macaca fascicularis , Masculino
5.
J Neurooncol ; 152(3): 483-490, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33674992

RESUMEN

PURPOSE: Patients with glioblastoma (GBM) or brain metastases (MET) and atrial fibrillation (AF) might be at an increased risk of intracranial hemorrhage (ICH) due to anticoagulation (AC). Our aim was to assess this risk. METHODS: Our institution's database (from 2005 to 2017) was screened for patients with GBM or MET and AF with an indication for AC according to their CHA2DS2VASc stroke risk score (≥ 2). Required follow-up was at least 3 months. AC was either performed with heparins, phenprocoumon or non-Vitamin K antagonist oral anticoagulants. Applying the propensity score approach, patient cohorts (matched according to primary tumor, age, sex) were generated (GBM [or MET] with AF ± AC, GBM [or MET] without AF/AC, no GBM [or MET] but AF on AC). ICH was defined as clinical deterioration caused by new blood on imaging. A log rank test was performed to compare the risk for ICH between the three groups. RESULTS: In total, 104 patients were identified of which 49 with GBM (37% on AC) and 37 with MET (46% on AC) were successfully matched. Median follow up was 8.6 and 7.2 months, respectively. ICH occurred in 10.2% of GBM + AF and 12.2% GBM-AF, whereas 8% of patients with AF on AC suffered ICH (p = 0.076). 13.5% of patients with MET + AF had ICHs, in the controls it was 16% for MET-AF and 8% for AF on AC (p = 0.11). CONCLUSION: AC did not seem to influence the incidence of ICH in patients with glioblastoma or brain metastases within follow up of just under 9 months.


Asunto(s)
Fibrilación Atrial , Neoplasias Encefálicas , Glioblastoma , Administración Oral , Anticoagulantes/efectos adversos , Fibrilación Atrial/complicaciones , Fibrilación Atrial/tratamiento farmacológico , Neoplasias Encefálicas/complicaciones , Neoplasias Encefálicas/tratamiento farmacológico , Glioblastoma/complicaciones , Glioblastoma/tratamiento farmacológico , Glioblastoma/epidemiología , Humanos , Hemorragias Intracraneales/inducido químicamente , Hemorragias Intracraneales/epidemiología , Factores de Riesgo , Accidente Cerebrovascular/tratamiento farmacológico
8.
Health Info Libr J ; 37(1): 60-69, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31628724

RESUMEN

BACKGROUND: Research is an important activity that informs knowledge and practice. The research culture within the Australian Health Information Management (HIM) profession has not been previously reported. OBJECTIVE: This study explored the perceptions of HIM practitioners about research in their role to establish if there is a research culture in the Australian HIM profession. METHOD: An online survey was distributed to the HIM community using a snowball recruitment strategy. RESULTS: Of the 149 respondents, more than half (54%) identified they possessed research skills from prior education, whilst 40% considered they had a strong knowledgebase in conducting research. However, only a quarter of respondents indicated that they should undertake research in their role. Barriers to undertaking research included recognition, organisational support and time. DISCUSSION: The findings from this study reflected other studies within clinical workforces. The lack of recognition and support to incorporate research into practitioner roles has implications for the profession and its body of knowledge. CONCLUSION: Advocating for research to be incorporated into practitioner roles is required to inform knowledge and practice. Increased professional development opportunities may create a stronger research culture within the HIM profession in Australia and strengthen the position of the profession within health.


Asunto(s)
Gestión de la Información/métodos , Investigación/normas , Adulto , Anciano , Australia , Estudios Transversales , Femenino , Humanos , Gestión de la Información/instrumentación , Gestión de la Información/normas , Internet , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Investigación/estadística & datos numéricos , Encuestas y Cuestionarios
10.
Biochem Biophys Res Commun ; 504(1): 19-24, 2018 09 26.
Artículo en Inglés | MEDLINE | ID: mdl-30126632

RESUMEN

Patients with severe Th2 type asthma often have a steroid resistant phenotype and are prone to acute exacerbations. Current novel therapies have only marginal therapeutic effects. One of the hypotheses for lack of major efficacy in most patients is targeting only one redundant pathway leaving others active. Hence, we have designed and developed novel highly potent bispecific anti-TSLP/IL13 antibodies called Zweimabs (monovalent bispecific) and Doppelmabs (bivalent bispecific) that concurrently inhibits the signaling by these two cytokines.


Asunto(s)
Anticuerpos Biespecíficos/química , Citocinas/inmunología , Interleucina-13/inmunología , Anticuerpos Monoclonales/química , Células Cultivadas , Citocinas/química , Mapeo Epitopo , Humanos , Interleucina-13/química , Linfopoyetina del Estroma Tímico
11.
Semin Neurol ; 38(1): 86-94, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29548055

RESUMEN

Primary central nervous system lymphoma (PCNSL) is an extranodal non-Hodgkin lymphoma limited to the brain, spinal cord, leptomeninges, and eyes. The majority of patients are immunocompetent, with a median age of 65 years at diagnosis. Historically, whole-brain radiation therapy (WBRT) was the first and sole treatment for PCNSL. Today, due to the recognized neurotoxicity of WBRT, this modality is usually avoided in the treatment. Most chemotherapy regimens are based on high-dose methotrexate plus the anti-CD20 monoclonal antibody rituximab, leading to high response rates, but 5-year survival is still poor at approximately 30% compared with other extranodal lymphomas. New treatment strategies including high-dose chemotherapy/autologous stem cell transplantation, targeted therapies focusing on, for example, genetic alterations in B cells or mammalian target of rapamycin signaling, and immunotherapy with inhibitors of the programmed cell death 1 receptor are only a few options to improve the armamentarium against PCNSL.


Asunto(s)
Antineoplásicos/uso terapéutico , Neoplasias del Sistema Nervioso Central/terapia , Linfoma no Hodgkin/terapia , Radioterapia/métodos , Trasplante de Células Madre/métodos , Humanos , Trasplante Autólogo
12.
J Neurosci ; 35(33): 11682-93, 2015 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-26290245

RESUMEN

The nociceptin/orphanin FQ (NOP) receptor, the fourth member of the opioid receptor family, is involved in many processes common to the opioid receptors including pain and drug abuse. To better characterize receptor location and trafficking, knock-in mice were created by inserting the gene encoding enhanced green fluorescent protein (eGFP) into the NOP receptor gene (Oprl1) and producing mice expressing a functional NOP-eGFP C-terminal fusion in place of the native NOP receptor. The NOP-eGFP receptor was present in brain of homozygous knock-in animals in concentrations somewhat higher than in wild-type mice and was functional when tested for stimulation of [(35)S]GTPγS binding in vitro and in patch-clamp electrophysiology in dorsal root ganglia (DRG) neurons and hippocampal slices. Inhibition of morphine analgesia was equivalent when tested in knock-in and wild-type mice. Imaging revealed detailed neuroanatomy in brain, spinal cord, and DRG and was generally consistent with in vitro autoradiographic imaging of receptor location. Multicolor immunohistochemistry identified cells coexpressing various spinal cord and DRG cellular markers, as well as coexpression with µ-opioid receptors in DRG and brain regions. Both in tissue slices and primary cultures, the NOP-eGFP receptors appear throughout the cell body and in processes. These knock-in mice have NOP receptors that function both in vitro and in vivo and appear to be an exceptional tool to study receptor neuroanatomy and correlate with NOP receptor function. SIGNIFICANCE STATEMENT: The NOP receptor, the fourth member of the opioid receptor family, is involved in pain, drug abuse, and a number of other CNS processes. The regional and cellular distribution has been difficult to determine due to lack of validated antibodies for immunohistochemical analysis. To provide a new tool for the investigation of receptor localization, we have produced knock-in mice with a fluorescent-tagged NOP receptor in place of the native NOP receptor. These knock-in mice have NOP receptors that function both in vitro and in vivo and have provided a detailed characterization of NOP receptors in brain, spinal cord, and DRG neurons. They appear to be an exceptional tool to study receptor neuroanatomy and correlate with NOP receptor function.


Asunto(s)
Proteínas Fluorescentes Verdes/metabolismo , Microscopía Fluorescente/métodos , Neuronas/citología , Neuronas/metabolismo , Receptores Opioides/metabolismo , Fracciones Subcelulares/metabolismo , Animales , Células Cultivadas , Técnicas de Sustitución del Gen , Proteínas Fluorescentes Verdes/genética , Masculino , Ratones , Ratones Transgénicos , Imagen Molecular/métodos , Receptores Opioides/genética , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Fracciones Subcelulares/ultraestructura , Distribución Tisular , Receptor de Nociceptina
13.
Am J Public Health ; 105(3): e114-21, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25602887

RESUMEN

OBJECTIVES: We investigated the health and safety effects of urban green stormwater infrastructure (GSI) installments. METHODS: We conducted a difference-in-differences analysis of the effects of GSI installments on health (e.g., blood pressure, cholesterol and stress levels) and safety (e.g., felonies, nuisance and property crimes, narcotics crimes) outcomes from 2000 to 2012 in Philadelphia, Pennsylvania. We used mixed-effects regression models to compare differences in pre- and posttreatment measures of outcomes for treatment sites (n=52) and randomly chosen, matched control sites (n=186) within multiple geographic extents surrounding GSI sites. RESULTS: Regression-adjusted models showed consistent and statistically significant reductions in narcotics possession (18%-27% less) within 16th-mile, quarter-mile, half-mile (P<.001), and eighth-mile (P<.01) distances from treatment sites and at the census tract level (P<.01). Narcotics manufacture and burglaries were also significantly reduced at multiple scales. Nonsignificant reductions in homicides, assaults, thefts, public drunkenness, and narcotics sales were associated with GSI installation in at least 1 geographic extent. CONCLUSIONS: Health and safety considerations should be included in future assessments of GSI programs. Subsequent studies should assess mechanisms of this association.


Asunto(s)
Drenaje de Agua/normas , Planificación Ambiental , Seguridad , Salud Urbana/estadística & datos numéricos , Calidad del Agua/normas , Crimen/prevención & control , Crimen/psicología , Crimen/estadística & datos numéricos , Drenaje de Agua/métodos , Ecosistema , Humanos , Naturaleza , Philadelphia , Plantas , Lluvia , Análisis de Regresión , Características de la Residencia , Aguas del Alcantarillado , Estrés Psicológico/complicaciones , Estrés Psicológico/prevención & control
14.
BMC Genomics ; 15: 345, 2014 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-24884839

RESUMEN

BACKGROUND: Opioids are the cornerstone of treatment for moderate to severe pain, but chronic use leads to maladaptations that include: tolerance, dependence and opioid-induced hyperalgesia (OIH). These responses limit the utility of opioids, as well as our ability to control chronic pain. Despite decades of research, we have no therapies or proven strategies to overcome this problem. However, murine haplotype based computational genetic mapping and a SNP data base generated from analysis of whole-genome sequence data (whole-genome HBCGM), provides a hypothesis-free method for discovering novel genes affecting opioid maladaptive responses. RESULTS: Whole genome-HBCGM was used to analyze phenotypic data on morphine-induced tolerance, dependence and hyperalgesia obtained from 23 inbred strains. The robustness of the genetic mapping results was analyzed using strain subsets. In addition, the results of analyzing all of the opioid-related traits together were examined. To characterize the functional role of the leading candidate gene, we analyzed transgenic animals, mRNA and protein expression in behaviorally divergent mouse strains, and immunohistochemistry in spinal cord tissue. Our mapping procedure identified the allelic pattern within the netrin-1 receptor gene (Dcc) as most robustly associated with OIH, and it was also strongly associated with the combination of the other maladaptive opioid traits analyzed. Adult mice heterozygous for the Dcc gene had significantly less tendency to develop OIH, become tolerant or show evidence of dependence after chronic exposure to morphine. The difference in opiate responses was shown not to be due to basal or morphine-stimulated differences in the level of Dcc expression in spinal cord tissue, and was not associated with nociceptive neurochemical or anatomical alterations in the spinal cord or dorsal root ganglia in adult animals. CONCLUSIONS: Whole-genome HBCGM is a powerful tool for identifying genes affecting biomedical traits such as opioid maladaptations. We demonstrate that Dcc affects tolerance, dependence and OIH after chronic opioid exposure, though not through simple differences in expression in the adult spinal cord.


Asunto(s)
Hiperalgesia/inducido químicamente , Morfina/administración & dosificación , Receptores de Superficie Celular/genética , Animales , Conducta Animal/efectos de los fármacos , Mapeo Cromosómico , Bases de Datos Factuales , Tolerancia a Medicamentos , Genoma , Haplotipos , Heterocigoto , Hiperalgesia/genética , Hiperalgesia/patología , Inyecciones Subcutáneas , Ratones , Ratones Endogámicos C57BL , Morfina/efectos adversos , Morfina/farmacología , Receptores de Netrina , Proteínas/metabolismo , ARN/metabolismo , Receptores de Superficie Celular/metabolismo , Médula Espinal/efectos de los fármacos , Médula Espinal/metabolismo
15.
J Neurochem ; 131(2): 251-64, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24976529

RESUMEN

Human glioblastomas may be hierarchically organized. Within this hierarchy, glioblastoma-initiating cells have been proposed to be more resistant to radiochemotherapy and responsible for recurrence. Here, established stem cell markers and stem cell attributed characteristics such as self-renewal capacity and tumorigenicity have been profiled in primary glioblastoma cultures to predict radiosensitivity. Furthermore, the sensitivity to radiotherapy of different subpopulations within a single primary glioblastoma culture was analyzed by a flow cytometric approach using Nestin, SRY (sex-determining region Y)-box 2 (SOX2) and glial fibrillary acidic protein. The protein expression of Nestin and SOX2 as well as the mRNA levels of Musashi1, L1 cell adhesion molecule, CD133, Nestin, and pleiomorphic adenoma gene-like 2 inversely correlated with radioresistance in regard to the clonogenic potential. Only CD44 protein expression correlated positively with radioresistance. In terms of proliferation, Nestin protein expression and Musashi1, pleiomorphic adenoma gene-like 2, and CD133 mRNA levels are inversely correlated with radioresistance. Higher expression of stem cell markers does not correlate with resistance to radiochemotherapy in the cancer genome atlas glioblastoma collective. SOX2 expressing subpopulations exist within single primary glioblastoma cultures. These subpopulations predominantly form the proliferative pool of the primary cultures and are sensitive to irradiation. Thus, profiling of established stem cell markers revealed a surprising result. Except CD44, the tested stem cell markers showed an inverse correlation between expression and radioresistance. Markers used to define glioma-initiating cells (GIC) are generally not defining a more resistant, but rather a more sensitive group of glioma cells. An exemption is CD44 expression. Also proliferation of the GIC culture itself was not systematically associated with radiosensitivity or - resistance, but a SOX-2 positive, proliferative subgroup within a GIC culture is showing the highest radiosensitivity.


Asunto(s)
Biomarcadores de Tumor/biosíntesis , Biomarcadores de Tumor/efectos de la radiación , Glioblastoma/radioterapia , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/efectos de la radiación , Animales , Femenino , Predicción , Glioblastoma/patología , Humanos , Ratones , Ratones Desnudos , Radioterapia/métodos , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto/métodos
16.
Am Fam Physician ; 89(7): 545-50, 2014 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-24695600

RESUMEN

Emergency contraception decreases the risk of unintended pregnancy after unprotected sexual intercourse or after suspected failure of routine contraception (e.g., a condom breaking). Oral methods include combined contraceptive pills (i.e., Yuzpe method), single- or split-dose levonorgestrel, and ulipristal. The Yuzpe method and levonorgestrel are U.S. Food and Drug Administration-approved for use 72 hours postcoitus, whereas the newest method, ulipristal, is approved for up to 120 hours postcoitus. The copper intrauterine device may be used as emergency contraception up to seven days after unprotected intercourse. It is nonhormonal and has the added benefit of long-term contraception. Advanced provision of emergency contraception may be useful for all patients, and for persons using ulipristal because it is available only by prescription. Physicians should counsel patients on the use and effectiveness of emergency contraception, the methods available, and the benefits of routine and consistent contraception use.


Asunto(s)
Anticoncepción Postcoital/métodos , Anticonceptivos Poscoito/administración & dosificación , Anticoncepción Postcoital/efectos adversos , Anticonceptivos Poscoito/efectos adversos , Femenino , Humanos , Embarazo , Resultado del Tratamiento
17.
A A Pract ; 18(6): e01792, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38828972

RESUMEN

Awake combined spinal caudal anesthesia has been used as an anesthetic technique for longer-duration infraumbilical surgeries in infants. Literature on the safety and feasibility of this technique is limited. We share our experience with 27 infants undergoing longer-duration urologic surgery using awake combined spinal and caudal anesthesia without the use of systemic sedatives or inhalational agents. We describe our technique, safety considerations, and details surrounding the optimal timing of caudal catheter activation for prolongation of surgical anesthesia.


Asunto(s)
Anestesia Caudal , Anestesia Raquidea , Procedimientos Quirúrgicos Urológicos , Humanos , Anestesia Caudal/métodos , Lactante , Procedimientos Quirúrgicos Urológicos/métodos , Anestesia Raquidea/métodos , Masculino , Femenino , Recién Nacido , Vigilia
18.
Proc Natl Acad Sci U S A ; 107(51): 22296-301, 2010 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-21135246

RESUMEN

Dorsal root ganglia (DRG) neurons, including the nociceptors that detect painful thermal, mechanical, and chemical stimuli, transmit information to spinal cord neurons via glutamatergic and peptidergic neurotransmitters. However, the specific contribution of glutamate to pain generated by distinct sensory modalities or injuries is not known. Here we generated mice in which the vesicular glutamate transporter 2 (VGLUT2) is ablated selectively from DRG neurons. We report that conditional knockout (cKO) of the Slc17a6 gene encoding VGLUT2 from the great majority of nociceptors profoundly decreased VGLUT2 mRNA and protein in these neurons, and reduced firing of lamina I spinal cord neurons in response to noxious heat and mechanical stimulation. In behavioral assays, cKO mice showed decreased responsiveness to acute noxious heat, mechanical, and chemical (capsaicin) stimuli, but responded normally to cold stimulation and in the formalin test. Strikingly, although tissue injury-induced heat hyperalgesia was lost in the cKO mice, mechanical hypersensitivity developed normally. In a model of nerve injury-induced neuropathic pain, the magnitude of heat hypersensitivity was diminished in cKO mice, but both the mechanical allodynia and the microgliosis generated by nerve injury were intact. These findings suggest that VGLUT2 expression in nociceptors is essential for normal perception of acute pain and heat hyperalgesia, and that heat and mechanical hypersensitivity induced by peripheral injury rely on distinct (VGLUT2 dependent and VGLUT2 independent, respectively) primary afferent mechanisms and pathways.


Asunto(s)
Ganglios Espinales/metabolismo , Regulación de la Expresión Génica , Calor , Hiperalgesia/metabolismo , Nociceptores/metabolismo , Dolor/metabolismo , Proteína 2 de Transporte Vesicular de Glutamato/biosíntesis , Animales , Conducta Animal/efectos de los fármacos , Capsaicina/farmacología , Frío , Fijadores/farmacología , Formaldehído/farmacología , Hiperalgesia/genética , Ratones , Ratones Noqueados , Dolor/genética , Fármacos del Sistema Sensorial/farmacología , Proteína 2 de Transporte Vesicular de Glutamato/genética
19.
Am Fam Physician ; 97(9): Online, 2018 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-29763250
20.
NPJ Parkinsons Dis ; 9(1): 91, 2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-37322068

RESUMEN

Prion-like transmission of pathology in α-synucleinopathies like Parkinson's disease or multiple system atrophy is increasingly recognized as one potential mechanism to address disease progression. Active and passive immunotherapies targeting insoluble, aggregated α-synuclein are already being actively explored in the clinic with mixed outcomes so far. Here, we report the identification of 306C7B3, a highly selective, aggregate-specific α-synuclein antibody with picomolar affinity devoid of binding to the monomeric, physiologic protein. 306C7B3 binding is Ser129-phosphorylation independent and shows high affinity to several different aggregated α-synuclein polymorphs, increasing the likelihood that it can also bind to the pathological seeds assumed to drive disease progression in patients. In support of this, highly selective binding to pathological aggregates in postmortem brains of MSA patients was demonstrated, with no staining in samples from other human neurodegenerative diseases. To achieve CNS exposure of 306C7B3, an adeno-associated virus (AAV) based approach driving expression of the secreted antibody within the brain of (Thy-1)-[A30P]-hα-synuclein mice was used. Widespread central transduction after intrastriatal inoculation was ensured by using the AAV2HBKO serotype, with transduction being spread to areas far away from the inoculation site. Treatment of (Thy-1)-[A30P]-hα-synuclein mice at the age of 12 months demonstrated significantly increased survival, with 306C7B3 concentration reaching 3.9 nM in the cerebrospinal fluid. These results suggest that AAV-mediated expression of 306C7B3, targeting extracellular, presumably disease-propagating aggregates of α-synuclein, has great potential as a disease-modifying therapy for α-synucleinopathies as it ensures CNS exposure of the antibody, thereby mitigating the selective permeability of the blood-brain barrier.

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