Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 18 de 18
Filtrar
1.
J Vitreoretin Dis ; 8(4): 471-475, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39148575

RESUMEN

Purpose: To present a case of central retinal artery occlusion (CRAO) leading to the diagnosis of eosinophilic granulomatosis with polyangiitis (Churg-Strauss syndrome) within 1 week of an adenovirus vector COVID-19 vaccination. Methods: A case was reviewed. Results: A 50-year-old man with atopic dermatitis and asthma presented with acute painless vision loss in 1 eye. An examination and imaging findings showed CRAO. Further evaluation found eosinophilia and elevated inflammatory markers. A workup for vasculitis showed elevated cytoplasmic-antineutrophil cytoplasmic antibody, perinuclear-antineutrophil cytoplasmic antibody, myeloperoxidase antibody, rheumatoid factor, and total immunoglobulin E. Skin biopsies were consistent with eosinophilic granulomatosis with polyangiitis. Steroids, cyclophosphamide, and mepolizumab were initiated. At 1 year, the patient's systemic symptoms had improved but his vision had not. Conclusions: Few reports exist of CRAO associated with eosinophilic granulomatosis with polyangiitis, with no other instances related to an adenovirus vector COVID-19 vaccination. Treating a systemic vasculitis early can be vision saving in the fellow eye and prevent systemic life-threatening complications.

2.
J AAPOS ; 27(5): 279.e1-279.e4, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37717616

RESUMEN

PURPOSE: To evaluate the ability of observers to accurately detect strabismus using an alternate cover testing approach via telemedicine and to assess the effect of various factors related to video conditions on the accuracy rate. METHODS: Videos were made by the authors in which different angles of strabismus, up to 12Δ, were induced by prism and recorded using alternate cover testing. The videos were made under a variety of conditions that incorporated various head postures, lighting, fixation target position and motion, and viewing angle. The videos were shown to observers of varying levels of expertise. The accuracy of detecting the deviation was assessed and analyzed for statistical significance. RESULTS: The overall rate of detection was significantly affected by the angle of deviation, with 12Δ being correctly detected with 94% accuracy, 8Δ with 72% accuracy, and 4Δ with <50% accuracy. Esotropia and hypertropia were more accurately detected than exotropia for all angles tested. The level of training of the observer did not correlate with detection accuracy. However, accuracy was negatively affected by backlighting and movement of the fixation target during cover testing. CONCLUSIONS: Our data demonstrate that detection of even relatively small angles of strabismus can be accomplished with a high level of accuracy using telemedicine and an alternate cover testing strategy. For optimal results, it is important to consider conditions related to the fixation target and lighting.


Asunto(s)
Esotropía , Exotropía , Estrabismo , Telemedicina , Humanos , Visión Binocular , Estrabismo/diagnóstico , Esotropía/cirugía , Exotropía/diagnóstico , Modelos Teóricos
3.
bioRxiv ; 2023 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-37503031

RESUMEN

Introduction: Inflammation is a key pathogenic feature of abdominal aortic aneurysm (AAA). Soluble epoxide hydrolase (sEH) is a pro-inflammatory enzyme that converts cytochrome P450-derived epoxides of fatty acids to the corresponding diols, and pharmacological inhibition of sEH prevented AAA formation. Both cytochrome P450 enzymes and sEH are highly expressed in the liver. Here, we investigated the role of hepatic sEH in AAA using a selective pharmacological inhibitor of sEH and hepatocyte-specific Ephx2 (which encodes sEH gene) knockout (KO) mice in two models of AAA [angiotensin II (AngII) infusion and calcium chloride (CaCl 2 ) application]. Methods and results: sEH expression and activity were strikingly higher in mouse liver compared with aorta and further increased the context of AAA, in conjunction with elevated expression of the transcription factor Sp1 and the epigenetic regulator Jarid1b, which have been reported to positively regulate sEH expression. Pharmacological sEH inhibition, or liver-specific sEH disruption, achieved by crossing sEH floxed mice with albumin-cre mice, prevented AAA formation in both models, concomitant with reduced expression of hepatic sEH as well as complement factor 3 (C3) and serum amyloid A (SAA), liver-derived factors linked to AAA formation. Moreover, sEH antagonism markedly reduced C3 and SAA protein accumulation in the aortic wall. Co-incubation of liver ex vivo with aneurysm-prone aorta resulted in induction of sEH in the liver, concomitant with upregulation of Sp1, Jarid1b, C3 and SAA gene expression, suggesting that the aneurysm-prone aorta secretes factors that activate sEH and downstream inflammatory signaling in the liver. Using an unbiased proteomic approach, we identified a number of dysregulated proteins [ e.g., plastin-2, galectin-3 (gal-3), cathepsin S] released by aneurysm-prone aorta as potential candidate mediators of hepatic sEH induction. Conclusion: We provide the first direct evidence of the liver's role in orchestrating AAA via the enzyme sEH. These findings not only provide novel insight into AAA pathogenesis, but they have potentially important implications with regard to developing effective medical therapies for AAA.

4.
Artículo en Inglés | MEDLINE | ID: mdl-36780633

RESUMEN

BACKGROUND AND OBJECTIVE: To report the 3-year outcomes for endolaserless vitrectomy with intravitreal aflibercept injection (IAI) monotherapy for proliferative diabetic retinopathy (PDR)-related vitreous hemorrhage (VH). MATERIALS AND METHOD: Eyes underwent endolaserless vitrectomy and received one preoperative and intraoperative IAI followed by randomization to a q8week or q16week IAI group. Additional IAI was administered as needed. RESULTS: 31/40 eyes were randomized (14 q8week eyes, 17 q16week eyes). Through 152 weeks, q8week and q16week eyes received 18.6 and 12.1 IAI, respectively. Q8week eyes observed a 34 letter visual acuity (VA) increase (P = 0.003) compared to a 27 letter increase in the q16week group (P = 0.013). CONCLUSIONS: Endolaserless vitrectomy with aflibercept monotherapy for PDR-related VH provides significant long-term visual gains. Frequent IAI is required for fewer proliferative consequences. [Ophthalmic Surg Lasers Imaging Retina 2023;54:89-96.].


Asunto(s)
Diabetes Mellitus , Retinopatía Diabética , Humanos , Inhibidores de la Angiogénesis , Anticuerpos Monoclonales Humanizados , Bevacizumab/uso terapéutico , Diabetes Mellitus/tratamiento farmacológico , Diabetes Mellitus/cirugía , Retinopatía Diabética/complicaciones , Retinopatía Diabética/diagnóstico , Retinopatía Diabética/tratamiento farmacológico , Inyecciones Intravítreas , Factor A de Crecimiento Endotelial Vascular , Vitrectomía/efectos adversos , Hemorragia Vítrea/diagnóstico , Hemorragia Vítrea/etiología , Hemorragia Vítrea/cirugía
6.
Med Teach ; 43(1): 101-107, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32981408

RESUMEN

PURPOSE: Training of compassionate and empathetic physicians requires commitment by educators to make it a priority. Chaplains typically have time and training to effectively demonstrate compassionate care in the clinical setting. This qualitative study aims to explore perceived benefits among medical students from pastoral care shadowing in integrating compassion and spirituality into education curricula. METHODS: Sixty-four written reflections from first- and second-year medical students were collected from December 2018 to January 2020 after shadowing with hospital chaplains. Unprompted reflections were analyzed using coding networks. RESULTS: Four major themes identified included (1) learned values within pastoral care, (2) learned roles of pastoral care in the healthcare setting, (3) practiced spiritual assessment tools and resource identification, and (4) reflected personal impact on future career. Within each major theme, three to four sub-themes were further identified. CONCLUSIONS: Reflections support chaplain shadowing as a model for emphasizing spiritual and compassionate care through role-modeling, hands-on learning and reflective practices.


Asunto(s)
Clero , Estudiantes de Medicina , Curriculum , Empatía , Humanos , Espiritualidad
7.
Front Cardiovasc Med ; 7: 595011, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33195484

RESUMEN

Introduction: Abdominal aortic aneurysms (AAA) are characterized by localized inflammation, extracellular matrix degradation, and apoptosis of smooth muscle cells, which together lead to progressive and irreversible aortic dilation. Major risk factors for AAA include smoking and aging, both of which prominently alter gene expression via epigenetic mechanisms, including histone methylation (me) and acetylation (ac).However, little is known about epigenomic dynamics during AAA formation. Here, we profiled histone modification patterns in aortic tissues during AAA formation in two distinct mouse models; (1) angiotensin II (AngII) infusion in low density lipoprotein receptor (LDLR) knockout (KO) mice, and (2) calcium chloride (CaCl2) application in wild type mice. Methods and Results: AAA formed in both models, in conjunction with enhanced macrophage infiltration, elastin degradation and matrix metalloproteinases expression as evaluated by immunohistochemistry. To investigate the histone modification patterns during AAA formation, total histone proteins were extracted from AAA tissues, and histone H3 modifications were quantified using profiling kits. Intriguingly, we observed dynamic changes in histone H3 modifications of lysine (K) residues at different time points during AAA formation. In mature aneurysmal tissues at 3 weeks after AngII infusion, we detected reduced K4/K27/K36 monomethylation, K9 trimethylation K9, and K9/K56 acetylation (<70%), and increased K4 trimethylation (>130%). Conversely, in CaCl2-induced AAA, K4/K9/K27/K36/K79 monomethylation and K9/K18/K56 acetylation were reduced in AAA tissues, whereas K27 di-/tri-methylation and K14 acetylation were upregulated. Interestingly, K4/K27/K36 monomethylation, K9 trimethylation, and K9/K56 acetylation were commonly downregulated in both animal models, while no H3 modifications were uniformly upregulated. Western blot of AAA tissues confirmed markedly reduced levels of key H3 modifications, including H3K4me1, H3K9me3, and H3K56ac. Furthermore, pathway enrichment analysis using an integrative bioinformatics approach identified specific molecular pathways, including endocytosis, exon guidance and focal adhesion signaling, that may potentially be linked to these histone H3 modifications during AAA formation. Conclusions: Dynamic modifications of histone H3 occur during AAA formation in both animal models. We identified 6 discreet H3 modifications that are consistently downregulated in both models, suggesting a possible role in AAA pathobiology. Identifying the functional mechanisms may facilitate development of novel strategies for AAA prevention or treatment.

8.
Cardiovasc Res ; 116(14): 2226-2238, 2020 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-31710686

RESUMEN

AIMS: Chronic adventitial and medial infiltration of immune cells play an important role in the pathogenesis of abdominal aortic aneurysms (AAAs). Nicotinic acid (niacin) was shown to inhibit atherosclerosis by activating the anti-inflammatory G protein-coupled receptor GPR109A [also known as hydroxycarboxylic acid receptor 2 (HCA2)] expressed on immune cells, blunting immune activation and adventitial inflammatory cell infiltration. Here, we investigated the role of niacin and GPR109A in regulating AAA formation. METHODS AND RESULTS: Mice were supplemented with niacin or nicotinamide, and AAA was induced by angiotensin II (AngII) infusion or calcium chloride (CaCl2) application. Niacin markedly reduced AAA formation in both AngII and CaCl2 models, diminishing adventitial immune cell infiltration, concomitant inflammatory responses, and matrix degradation. Unexpectedly, GPR109A gene deletion did not abrogate the protective effects of niacin against AAA formation, suggesting GPR109A-independent mechanisms. Interestingly, nicotinamide, which does not activate GPR109A, also inhibited AAA formation and phenocopied the effects of niacin. Mechanistically, both niacin and nicotinamide supplementation increased nicotinamide adenine dinucleotide (NAD+) levels and NAD+-dependent Sirt1 activity, which were reduced in AAA tissues. Furthermore, pharmacological inhibition of Sirt1 abrogated the protective effect of nicotinamide against AAA formation. CONCLUSION: Niacin protects against AAA formation independent of GPR109A, most likely by serving as an NAD+ precursor. Supplementation of NAD+ using nicotinamide-related biomolecules may represent an effective and well-tolerated approach to preventing or treating AAA.


Asunto(s)
Aorta Abdominal/efectos de los fármacos , Aneurisma de la Aorta Abdominal/prevención & control , NAD/metabolismo , Niacina/farmacología , Niacinamida/farmacología , Receptores Acoplados a Proteínas G/metabolismo , Angiotensina II , Animales , Aorta Abdominal/metabolismo , Aorta Abdominal/patología , Aneurisma de la Aorta Abdominal/inducido químicamente , Aneurisma de la Aorta Abdominal/metabolismo , Aneurisma de la Aorta Abdominal/patología , Cloruro de Calcio , Células Cultivadas , Dilatación Patológica , Modelos Animales de Enfermedad , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Receptores Acoplados a Proteínas G/genética , Receptores de LDL/genética , Receptores de LDL/metabolismo , Transducción de Señal , Sirtuina 1/metabolismo
9.
Stereotact Funct Neurosurg ; 86(2): 67-74, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18073518

RESUMEN

BACKGROUND/AIMS: No validated delivery technique exists for accurate, reproducible delivery of biological therapies to discrete spinal cord targets. To address this unmet need, we have constructed a stabilized platform capable of supporting physiologic mapping, through microelectrode recording, and cellular or viral payload delivery to the ventral horn. METHODS: A porcine animal model (n = 7) has been chosen based upon the inherent morphologic similarities between the human and porcine spine. Animals underwent physiologic mapping and subsequent microinjection of a green-fluorescent-protein-labeled cell suspension. Sacrifice (t = 3 h) was performed immediately following behavioral assessment. RESULTS: Histologic analysis has supported our ability to achieve localization to the ipsilateral ventral horn in the spinal cord. Complications included death due to malignant hyperthermia (n = 1), hindlimb dysfunction attributable to epidural hematoma (n = 1), and hindlimb dysfunction attributable to cord penetration (n = 2). CONCLUSIONS: These results indicate an ability to achieve accurate targeting, but the elevated incidence of neurologic morbidity will require further studies with longer follow-ups that incorporate procedural and equipment modifications that will allow for a reduced number of cord penetrations and will account for observed cardiorespiratory-associated cord movement. These initial results reinforce the challenges of translating biological restorative therapies from small to large animal models and ultimately to humans.


Asunto(s)
Tratamiento Basado en Trasplante de Células y Tejidos/métodos , Microinyecciones/métodos , Médula Espinal/patología , Médula Espinal/fisiología , Técnicas Estereotáxicas/instrumentación , Animales , Células del Asta Anterior/patología , Células del Asta Anterior/fisiología , Conducta Animal/fisiología , Tratamiento Basado en Trasplante de Células y Tejidos/instrumentación , Corteza Cerebral/patología , Potenciales Evocados Motores/fisiología , Femenino , Microelectrodos , Microinyecciones/efectos adversos , Microinyecciones/instrumentación , Modelos Animales , Ratas , Reproducibilidad de los Resultados , Técnicas Estereotáxicas/efectos adversos , Porcinos
10.
Neuromolecular Med ; 9(3): 276-84, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17914186

RESUMEN

Clostridial light chain (LC) inhibits synaptic transmission by digesting a vesicle-docking protein, synaptobrevin, without killing neurons. We here report the feasibility of creating a rat hemiparkinsonism model through LC gene expression in the substantia nigra (SN), inhibiting nigrostriatal transmission. 40 adult Sprague Dawley rats were divided into four groups for SN injections of PBS, 6-hydroxydopamine (6-OHDA), or adenoviral vectors for the expression of LC (AdLC), or GFP (AdGFP). Amphetamine and apomorphine induced rotations were assessed before and after SN injection, revealing significant rotational alterations at 8 or 10 days after injection in both AdLC and 6-OHDA but not PBS and AdGFP groups. Induced rotation recovered by one month in AdLC rats but persisted in 6-OHDA rats. Histological analysis of the SN revealed LC and GFP expression with corresponding synaptobrevin depletion in the LC, but not the GFP groups. Tyrosine hydroxylase (TH) and dopamine transporter (DAT) immunohistochemistry (IHC) showed markedly decreased staining in ipsilateral SN and striatum in 6-OHDA but not AdLC or AdGFP rats. Similarly, compared with contralateral, ipsilateral striatal dopamine level only decreased in 6-OHDA but not AdLC, AdGFP, or PBS treated rats. Thus, LC expression induces nigral synaptobrevin depletion with resulting inhibition of nigrostriatal synaptic transmission. Unlike 6-OHDA, LC expression inhibits synaptic activity without killing neurons. This approach, therefore, represents a potentially reversible means of nigrostriatal pathway inhibition as a model for Parkinson's disease. Such a model might facilitate transient and controlled nigral inhibition for studying striatal recovery, dopaminergic re-innervation, and normalization of striatal receptors following the recovery of nigrostriatal transmission.


Asunto(s)
Adenoviridae/genética , Clostridium/metabolismo , Metaloendopeptidasas/biosíntesis , Trastornos Parkinsonianos/fisiopatología , Transducción de Señal/fisiología , Sustancia Negra/fisiología , Toxina Tetánica/biosíntesis , Animales , Modelos Animales de Enfermedad , Dopamina/análisis , Masculino , Metaloendopeptidasas/genética , Oxidopamina , Trastornos Parkinsonianos/inducido químicamente , Proteínas R-SNARE/metabolismo , Ratas , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacos , Conducta Estereotipada , Transmisión Sináptica , Toxina Tetánica/genética
11.
J Drug Target ; 14(5): 263-71, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16882546

RESUMEN

Phage display is a promising tool for the screening of peptides with high affinity for specific cells. Here we describe a novel peptide with neuronal affinity isolated from a C7C library. We designed a two-tiered biopanning strategy initially selecting for ganglioside binding and subsequently selecting for binding to PC12 cells. At the completion of biopanning, 54.8% of phage clones bore the identical peptide (Tet.C7C.1). Immunofluorescence confirmed selective binding of this clone to differentiated PC12 cells. Tet.C7C.1 was synthesized and fluorescein conjugated. The synthetic peptide binds neuronal cell lines (SH-SY5Y, NSC-34 and PC12 cells) and tissue (DRG and spinal cord). The C7C structure creates a loop that minimizes the impact of peptide insertion on the confirmation of the recipient protein. Small loop peptides have the ideal characteristics for modification of viral vector capsids without undermining genome packaging. The neuronal binding properties of this peptide may be applied in the development of neurotropic viral vectors.


Asunto(s)
Neuronas/metabolismo , Biblioteca de Péptidos , Péptidos/metabolismo , Secuencia de Aminoácidos , Animales , Células Cultivadas , Humanos , Células PC12 , Péptidos/química , Péptidos/genética , Unión Proteica , Ratas
12.
Neurosurgery ; 59(1): 172-82; discussion 172-82, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16823314

RESUMEN

OBJECTIVE: The recently discovered X-linked inhibitor of apoptosis protein (XIAP) is among the most potent inhibitors of programmed cell death. In the current experiment, we examine the potential of adenoviral XIAP gene delivery to protect neurons of the peripheral nervous system using in vitro models of amyotrophic lateral sclerosis (ALS) and diabetic neuropathy. METHODS: XIAP complementary deoxyribonucleic acid was fused in frame with the green fluorescent protein sequence and cloned into a first generation adenoviral vector. The impact of XIAP gene expression on glutamate-induced apoptosis was measured in the neuronal SH-SY5Y cell line with immunohistochemistry for active caspase-3 and with cell density assays. Next, the effect of XIAP expressing neurons on the survival of uninfected neighboring neurons was measured. Finally, the impact of XIAP gene expression on glutamate-induced apoptosis was assessed in embryonic motor neuron and dorsal root ganglion cultures. RESULTS: XIAP gene expression reduced the percentage of active caspase-3 positive SH-SY5Y neurons and preserved cell density after glutamate exposure. In heterogeneously infected cultures, cells infected with XIAP were protected, but uninfected neighboring cells were not. In primary E15 models, inhibition of proapoptotic effects was demonstrated after glutamate insult in motor neurons and glucose insult in dorsal root ganglion cells. CONCLUSION: XIAP gene delivery through the neurosurgical delivery of viral vectors may provide a means for neuroprotection in ALS and diabetic neuropathy.


Asunto(s)
Esclerosis Amiotrófica Lateral/patología , Neuropatías Diabéticas/patología , Técnicas de Transferencia de Gen , Fármacos Neuroprotectores , Sistema Nervioso Periférico/patología , Proteína Inhibidora de la Apoptosis Ligada a X/genética , Esclerosis Amiotrófica Lateral/metabolismo , Apoptosis/efectos de los fármacos , Caspasa 3 , Caspasas/metabolismo , Recuento de Células , Línea Celular , Supervivencia Celular/efectos de los fármacos , Neuropatías Diabéticas/metabolismo , Estudios de Factibilidad , Ganglios Espinales/efectos de los fármacos , Expresión Génica , Ácido Glutámico/envenenamiento , Proteínas Fluorescentes Verdes/genética , Humanos , Neuronas Motoras/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Sistema Nervioso Periférico/efectos de los fármacos , Sistema Nervioso Periférico/metabolismo , Proteínas Recombinantes de Fusión/metabolismo , Proteína Inhibidora de la Apoptosis Ligada a X/farmacología
13.
Muscle Nerve ; 32(6): 734-44, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16116646

RESUMEN

Recent work implicates excitotoxicity-induced apoptosis as the mechanism triggering motor neuron death in amyotrophic lateral sclerosis (ALS). Our laboratory has previously utilized glutamate excitotoxicity in vitro to study this process. The present experiment tests whether overexpression of the gene for Bcl-xL can inhibit excitotoxicity in this model system. To track Bcl-xL expression, the gene for green fluorescent protein (GFP) was inserted in-frame, upstream of the Bcl-xL gene. The GFP-Bcl-xL gene was then cloned into an adeno-associated viral (AAV2) vector. GFP expression in both SH-SY5Y and embryonic day 15 (E15) motor neurons (MNs) peaked 48 hours after infection. Bcl-xL expression in SH-SY5Y cells significantly reduced terminal deoxy-UTP nick-end labeling (TUNEL)-positive cells and maintained cell density after glutamate exposure. Similarly, Bcl-xL expression inhibited the development of TUNEL staining in E15 MNs and supported cell density after glutamate exposure. These findings suggest that AAV-mediated expression of genes for antiapoptotic proteins may provide a means for ALS gene therapy.


Asunto(s)
Dependovirus/fisiología , Técnicas de Transferencia de Gen , Enfermedad de la Neurona Motora/prevención & control , Proteína bcl-X/genética , Proteína bcl-X/metabolismo , Análisis de Varianza , Animales , Animales Recién Nacidos , Apoptosis/fisiología , Western Blotting/métodos , Caspasa 3 , Caspasas/metabolismo , Recuento de Células/métodos , Células Cultivadas , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Activación Enzimática/efectos de los fármacos , Expresión Génica/fisiología , Regulación de la Expresión Génica/fisiología , Vectores Genéticos/fisiología , Ácido Glutámico/efectos adversos , Proteínas Fluorescentes Verdes/metabolismo , Humanos , Inmunohistoquímica/métodos , Etiquetado Corte-Fin in Situ/métodos , Enfermedad de la Neurona Motora/genética , Neuroblastoma , Ratas , Ratas Sprague-Dawley , Factores de Tiempo , Transfección/métodos
14.
Neurobiol Dis ; 20(3): 694-700, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16005636

RESUMEN

The present study examines gene delivery to cultured motor neurons (MNs) with the Rabies G protein (RabG)-pseudotyped lentiviral equine infectious anemia virus (RabG.EIAV) vector. RabG.EIAV-mediated beta-galactosidase (RabG.EIAV-LacZ) gene expression in cultured MNs plateaus 120 h after infection. The rate and percent of gene expression observed are titer-dependent (P < 0.001). The rat IGF-I cDNA sequence was then cloned into a RabG.EIAV vector (RabG.EIAV-IGF-I) and was shown to induce IGF-I expression in HEK 293 cells. MNs infected with RabG.EIAV-IGF-I demonstrate enhanced survival compared to MNs infected with RabG.EIAV-LacZ virus (P < 0.01). In addition, IGF-I expression in cultured MNs induced profound MN axonal elongation compared to control virus (P < 0.01). The enhanced motor neuron tropism of RabG.EIAV previously demonstrated in vivo, together with the trophic effects of RabG.EIAV-IGF-I MN gene expression may lend this vector to therapeutic application in motor neuron disease.


Asunto(s)
Técnicas de Transferencia de Gen , Vectores Genéticos/genética , Virus de la Anemia Infecciosa Equina/genética , Factor I del Crecimiento Similar a la Insulina/genética , Neuronas Motoras/metabolismo , Factores de Crecimiento Nervioso/genética , Animales , Supervivencia Celular/genética , Células Cultivadas , Regulación del Desarrollo de la Expresión Génica/genética , Regulación Viral de la Expresión Génica/genética , Terapia Genética/métodos , Conos de Crecimiento/metabolismo , Conos de Crecimiento/virología , Humanos , Enfermedad de la Neurona Motora/genética , Enfermedad de la Neurona Motora/metabolismo , Enfermedad de la Neurona Motora/terapia , Fragmentos de Péptidos/genética , Regiones Promotoras Genéticas/genética , Ratas , Ratas Sprague-Dawley , Receptor IGF Tipo 1/metabolismo , Médula Espinal/embriología , Médula Espinal/metabolismo , Médula Espinal/virología , Células Tumorales Cultivadas , Proteínas del Envoltorio Viral/genética
15.
Neurobiol Dis ; 19(3): 407-18, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16023583

RESUMEN

A novel peptide with the binding characteristics of tetanus toxin was identified with phage display, for application in therapeutic protein and vector motor and sensory neuron targeting. A 12mer phage library was biopanned on trisialoganglioside (G(T1b)) and eluted with the tetanus toxin C fragment (rTTC). Phage ELISAs revealed increases in G(T1b) binding for the Tet1 and Tet2 phage clones when compared to peptideless phage (PLP). rTTC displaced both Tet1 and Tet2 phage clones from G(T1b), and both clones reduced rTTC-G(T1b) binding. Comparison of Tet1, Tet2, PLP, and the random phage library binding to PC12 and HEK293 cells revealed enhanced cellular binding by Tet1 and Tet2 phage. Tet1 phage binding was selective for neurons. Immunofluorescence also confirmed selective PC12 binding of Tet1 and Tet2 phage. Fluorescein-conjugated synthetic Tet1, but not Tet2, peptide showed strong binding to cultured PC12, primary motor neurons, and dorsal root ganglion (DRG) cells. Synthetic Tet1 bound DRG and motor neurons but not muscle in tissue sections. The enhanced neuronal binding affinity and specificity of Tet1, a novel 12 amino acid peptide, suggests potential utility for targeting neurotherapeutic proteins and viral vectors in the treatment of motor neuron disease, neuropathy, and pain.


Asunto(s)
Gangliósidos/metabolismo , Neuronas Motoras/metabolismo , Biblioteca de Péptidos , Péptidos/metabolismo , Toxina Tetánica/metabolismo , Secuencia de Aminoácidos , Animales , Unión Competitiva , Encéfalo/metabolismo , Ensayo de Inmunoadsorción Enzimática , Técnica del Anticuerpo Fluorescente , Ganglios Espinales/metabolismo , Humanos , Imitación Molecular/fisiología , Datos de Secuencia Molecular , Células PC12 , Péptidos/genética , Ratas , Ratas Sprague-Dawley , Homología de Secuencia de Aminoácido , Médula Espinal/metabolismo , Toxina Tetánica/química
16.
Glia ; 51(1): 65-72, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15779084

RESUMEN

Electric fields impact cellular functions by activation of ion channels or by interfering with cell membrane integrity. Ion channels can regulate cell cycle and play a role in tumorigenesis. While the cell cycle may be directly altered by ion fluxes, exposure to direct electric current of sufficient intensity may decrease tumor burden by generating chemical products, including cytotoxic molecules or heat. We report that in the absence of thermal influences, low-frequency, low-intensity, alternating current (AC) directly affects cell proliferation without a significant deleterious contribution to cell survival. These effects were observed in normal human cells and in brain and prostate neoplasms, but not in lung cancer. The effects of AC stimulation required a permissive role for GIRK2 (or K(IR)3.2) potassium channels and were mimicked by raising extracellular potassium concentrations. Cell death could be achieved at higher AC frequencies (>75 Hz) or intensities (>8.5 microA); at lower frequencies/intensities, AC stimulation did not cause apoptotic cellular changes. Our findings implicate a role for transmembrane potassium fluxes via inward rectifier channels in the regulation of cell cycle. Brain stimulators currently used for the treatment of neurological disorders may thus also be used for the treatment of brain (or other) tumors.


Asunto(s)
Proliferación Celular , Neoplasias/patología , Adenilato Quinasa/metabolismo , Astrocitos/fisiología , Western Blotting , Bromodesoxiuridina , Caspasa 3 , Caspasas/metabolismo , Ciclo Celular/fisiología , Estimulación Eléctrica , Epilepsia/patología , Canales de Potasio Rectificados Internamente Asociados a la Proteína G , Calor , Humanos , Inmunohistoquímica , Neoplasias/terapia , Potasio/farmacología , Canales de Potasio de Rectificación Interna/metabolismo
17.
J Neurosurg Spine ; 1(1): 128-36, 2004 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15291033

RESUMEN

OBJECT: Lentiviral vectors may constitute a vehicle for long-term therapeutic gene expression in the spinal cord. In amyotrophic lateral sclerosis, spinal cord sclerosis and altered axonal transport pose barriers to therapeutic gene distribution. In the present study the authors characterize gene expression distribution and the behavioral impact of the rabies G (RabG) protein pseudotyped lentiviral vector EIAV.LacZ through cervical spinal cord injection in control and Cu/Zn superoxide dismutase-1 (SOD-1) transgenic mice. METHODS: Seven-week-old SOD-1 transgenic mice and their wild-type littermates underwent exposure of the cervicomedullary junction and microinjection of RabG.EIAV.LacZ or vehicle. The Basso-Beattie-Bresnahan locomotor score, grip strength meter, and Rotarod assays were used to assess the effects of disease progression, spinal cord microinjection, and lentiviral gene expression. Spinal cords were removed when the mice were in the terminal stage of the disease. The distribution of LacZ gene expression was histologically evaluated and quantified. Direct cervical spinal cord microinjection of RabG.EIAV.LacZ results in extensive central nervous system uptake in SOD-1 transgenic mice; these findings were statistically similar to those in wild-type mice (p > 0.05). Gene expression lasts for the duration of the animal's survival (132 days). The SOD-1 mutation does not prevent retrograde axonal transport of the vector. Three behavioral assays were used to demonstrate that long-term gene expression does not alter sensorimotor function. In comparison with normative data, vector injection and transgene expression do not accelerate disease progression. CONCLUSIONS: Direct spinal cord injection of RabG.EIAV vectors represents a feasible method for delivering therapeutic genes to upper cervical spinal cord and brainstem motor neurons. Distribution is not affected by the SOD-1 mutation or disease phenotype.


Asunto(s)
Esclerosis Amiotrófica Lateral/terapia , Antígenos Virales , Vectores Genéticos , Glicoproteínas/genética , Lentivirus/genética , Médula Espinal , Superóxido Dismutasa/genética , Proteínas del Envoltorio Viral/genética , Esclerosis Amiotrófica Lateral/mortalidad , Esclerosis Amiotrófica Lateral/fisiopatología , Animales , Vértebras Cervicales , Modelos Animales de Enfermedad , Terapia Genética/métodos , Inyecciones Espinales , Ratones , Ratones Transgénicos , Microinyecciones , Actividad Motora , Superóxido Dismutasa-1 , Tasa de Supervivencia
18.
Neurosurg Clin N Am ; 14(3): 419-35, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-14567143

RESUMEN

Technologic advancements have made cell type-specific targeting, expression control, and safe and stable gene transfer possible. Animal research has provided increasing experience with gene transfer to the nervous system and sensory neurons in particular. Gene-based neuromodultion can be achieved through neuronal delivery of transgenes capable of altering synaptic function. Alternatively, ex vivo gene transfer can be used to create cell lines capable of secreting analgesic neurepeptides. Translatation of these grafts and direct gene-based neuromoduation can be applied to the control of pain and the root causes of pain. These approaches combine anatomic and pharmacologic specificity. As the technology continues to improve, clinical application of cellular and molecular pain control is likely.


Asunto(s)
Terapia Genética , Biología Molecular/métodos , Manejo del Dolor , Cuidados Paliativos/métodos , Animales , Enfermedad Crónica , Técnicas de Transferencia de Gen , Humanos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA