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1.
J Gene Med ; 14(3): 204-15, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22328073

RESUMEN

BACKGROUND: Electrotransfer can be obtained by the successive delivery of a high voltage short duration pulse (HV) inducing membrane destabilization and then a low voltage long duration pulse (LV), allowing DNA electrophoresis (HVLV mode). Pluronic® L64 (L64) (Fluka, Sigma-Aldrich, L'Isle-d'Abeau Chesnes, Saint-Quentin Fallavier, France) has permeabilizing properties and amplifies the expression of DNA. We aimed to determine whether L64 could have an adjuvant effect on transfection by electrotransfer and whether the sequence L64 injection and then application of a LV pulse could induce transfection comparable to that observed with the HVLV mode. METHODS: In vitro, we used fluorescence-activated cell sorting to evaluate Chinese hamster ovary (CHO) cell transfection by a plasmid coding green fluorescent protein, and permeabilization to propidium iodide. In vivo, the transfection efficiency of mice tibial cranial muscle was evaluated by optical imaging using a plasmid DNA encoding luciferase. For the same animals, permeabilization indices were evaluated by magnetic resonance imaging from the uptake of a T(1) contrast agent. RESULTS: Using the HVLV mode, transfection efficiency was low in vitro on CHO cells but high for muscles in vivo. Pre-treatment by L64 increased the transfection efficiency of electrotransfer for CHO cells but not for muscle. In mice muscles, the L64 amplified the expression of DNA. Nevertheless, neither transgene expression, nor permeability indices were further amplified by subsequent delivery of one LV pulse. CONCLUSIONS: A major finding of the present study is that the nature of the membrane modification induced by electric pulses is not comparable to that mediated by L64. The electrophoretic LV pulse does not induce additive effects to that of L64 for transfection improvement.


Asunto(s)
Electroporación/métodos , Músculo Esquelético/metabolismo , Permeabilidad , Poloxámero/metabolismo , Transfección/métodos , Animales , Células CHO , Cricetinae , Cricetulus , Electroforesis/métodos , Citometría de Flujo , Proteínas Fluorescentes Verdes/metabolismo , Técnicas In Vitro , Luciferasas , Imagen por Resonancia Magnética , Ratones , Ratones Endogámicos BALB C , Plásmidos/genética , Poloxámero/química , Estadísticas no Paramétricas
2.
Crit Care Med ; 40(1): 278-80, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22179343

RESUMEN

OBJECTIVES: The benefit of arginine in intensive care unit patients with severe sepsis is still controversial. An excessive supply of arginine could lead to an overproduction of nitric oxide and could be responsible for septic shock and multiorgan failure. However, this claim is not supported by any experimental or clinical data. We set out to determine whether an enteral supply of arginine would modulate bacterial invasion in rats with head injury. METHODS: Male Sprague-Dawley rats with head injury were randomized into two groups. Group 1 included rats with head injury fed a standard enteral nutrition (Sondalis HP, n = 10) and group 2 included rats with head injury fed the standard enteral nutrition plus arginine (4 g/kg/d, n = 11). Two days after head injury, the rats received a single enteral bolus of luminescent Escherichia coli Xen 14. Bacterial proliferation was evaluated in vivo at time + 2 hrs and time + 6 hrs after E. coli challenge. Four days after head injury, blood was sampled for arginine and fibrinogen assay. Muscles, intestine, spleen, and thymus were removed and weighed. RESULTS: There was no mortality in either group. The luminescence signal was similar in the two groups at time +2 hrs (group 1: 414 [5-823] vs. group 2: 496 [0.1-993] (median value[min-max]; not significant) and was significantly lower at time +6 hrs in group 2 (group 1: 71 [0-142] vs. group 2: 8.5 [0-17]; p = .026). Arginine treatment did not improve any nutritional parameters. CONCLUSIONS: Arginine was not responsible for mortality in rats with head injury with infectious complications and reduced the intensity of bacterial invasion.


Asunto(s)
Arginina/uso terapéutico , Infecciones Bacterianas/prevención & control , Traumatismos Craneocerebrales/tratamiento farmacológico , Animales , Traumatismos Craneocerebrales/complicaciones , Traumatismos Craneocerebrales/microbiología , Nutrición Enteral/métodos , Mediciones Luminiscentes , Masculino , Ratas , Ratas Sprague-Dawley , Sepsis/prevención & control
3.
Can Urol Assoc J ; 16(10): 334-339, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35621285

RESUMEN

INTRODUCTION: During the first regional COVID-19 lockdown in March 2020, we conducted a study aimed at evaluating completeness of telemedicine consultation in urology. Of 1679 consultations, 67% were considered completely managed by phone. The aim of the present study was to assess patients' experience and satisfaction with telemedicine and to compare them with urologists' perceptions about quality and completeness of the telemedicine consultation. METHODS: We contacted a randomly selected sample of patients (n=356) from our previous study to enquire about their experience. We used a home patient experience questionnaire, inspired by the Patient Experiences Questionnaire for Out-of-Hours Care (PEQOHC) and the Consumer Assessment Health Profile Survey (CAHPS). RESULTS: Of 356 patients contacted, 315 agreed to complete the questionnaire. Urological consultations were for non-oncological (104), oncological (121), cancer suspicion (41), and pediatric (49) indications. Mean patient satisfaction score after telemedicine consultation was 8.8/10 (median 9/10) and 86.3% of patients rated the quality of the consultation as either excellent (54.6%) or very good (31.7%). Consultations regarding cancer suspicion had the lowest score (8.3/10). Overall, 46.7% of all patients would have preferred an in-person visit outside of the pandemic situation. Among patients whose consultations were rated suboptimal by urologists, almost a third more (31.2%) would have preferred an in-person visit (p=0.03). CONCLUSIONS: Despite high reported patient satisfaction rates with telemedicine, it is noteworthy that nearly half of the patients would have preferred an in-person visit. Post-pandemic, it will be important to incorporate telemedicine as an alternative, while retaining and offering in-person visits.

4.
Biochim Biophys Acta ; 1800(5): 537-43, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20153812

RESUMEN

BACKGROUND: Muscle transfection by electrotranfer is an efficient currently used procedure. Recently, the block copolymer pluronic L64 has been reported to improve muscle transfection. Both procedures are known to permeabilize muscle fibres. Relation between muscle transfection and permeabilization by electrotransfer and L64 was investigated herein. METHODS: Muscle transfection was evaluated by optical detection of the luciferase reporter gene activity. Muscle permeabilization was evaluated by the uptake of the T1 contrast agent gadolinium-Dotarem (Gd-DOTA) using Magnetic resonance imaging (MRI). Histological examination of muscle sections was also performed. RESULTS: Electrotransfer and L64 (at a 0.25% concentration) similarly improved muscle transfection, although the interindividual variability was higher for pluronic. On the same animals, the permeabilized volume to the Gd-DOTA was significantly increased after electrotransfer, and L64 from 0.1% to 1%. The concentration of the Gd-DOTA in the permeabilized volume was significantly increased after electrotransfer and L64 at 0.5% and 1%. By histological observation, the inflammation was maximum at day 3 after electrotransfer or L64 injection, and mostly reversed after 7 days. The permeabilized volume and the transfection level correlated for the set of all the conditions tested. However, no significant correlation was observed between Gd-DOTA concentration and transfection. GENERAL SIGNIFICANCE: It is possible to use successively on the same animals MRI and optical imaging for paired studies of muscle transfection and permeabilization. Permeabilization is possibly not related to gene transfer but it indicates membrane modification related to transfection by the electrotransfer or co-injection of DNA with the L64.


Asunto(s)
Medios de Contraste/farmacología , Electroporación/métodos , Compuestos Heterocíclicos/farmacología , Luciferasas/biosíntesis , Imagen por Resonancia Magnética/métodos , Fibras Musculares Esqueléticas/citología , Fibras Musculares Esqueléticas/metabolismo , Compuestos Organometálicos/farmacología , Poloxámero/farmacología , Animales , Femenino , Genes Reporteros , Ratones , Ratones Endogámicos BALB C , Factores de Tiempo
5.
J Gene Med ; 12(6): 491-500, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20527042

RESUMEN

BACKGROUND: Nonviral gene therapy still suffers from low efficiency. Methods that would lead to higher gene expression level of longer duration would be a major advance in this field. Lipidic vectors and physical methods have been investigated separately, and both induced gene expression improvement. METHODS: We sought to combine both chemical and physical methods. Cationic or anionic lipids can potentially destabilize the cell membrane and could consequently enhance gene delivery by a physical method such as electrotransfer. A plasmid model encoding luciferase was used, either free or associated with differently-charged lipoplexes before electrotransfer. RESULTS: Electrotransfer alone strongly enhanced gene expression after intramuscular and intradermal injection of naked DNA. On the other hand, cationic and anionic lipoplex formulations decreased gene expression after electrotransfer, whereas poorly-charged thiourea-based complexes, brought no benefit. Pre-injection of the lipids, followed by administration of naked DNA, did not modified gene expression induced by electroporation in the skin. CONCLUSIONS: The results obtained in the present study suggest that packing of DNA plasmid in lipoplexes strongly decreases the efficiency of gene electrotransfer, independently of the lipoplex charge. Non-aggregating complexes, such as poorly-charged thiourea-based complexes, should be preferred to increase DNA release.


Asunto(s)
Cationes/química , Electroporación/métodos , Técnicas de Transferencia de Gen , Liposomas/química , Transfección , Animales , Células CHO , Cationes/metabolismo , Cricetinae , Cricetulus , ADN/química , Femenino , Liposomas/metabolismo , Ratones , Ratones Endogámicos BALB C , Músculo Esquelético/citología , Músculo Esquelético/fisiología , Plásmidos/química , Plásmidos/genética , Piel/citología , Piel/metabolismo
6.
Can Urol Assoc J ; 14(10): 319-321, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33275552

RESUMEN

INTRODUCTION: The COVID-19 pandemic has accelerated the development of telemedicine due to confinement measures. However, the percentage of outpatient urological cases that could be managed completely by telemedicine outside of the COVID-19 pandemic remains to be determined. We conducted a prospective, multisite study involving all urologists working in the region of Quebec City. METHODS: During the first four weeks of the regional confinement, 18 pediatric and adult urologists were asked to determine, after each telemedicine appointment, if it translated into a complete (CCM), incomplete (ICM), or suboptimal case management (SCM, adequate only in the context of the pandemic). RESULTS: A total of 1679 appointments representing all urological areas were registered. Overall, 67.6% (95% confidence interval [CI] 65.3; 69.8), 27.1% (25.0; 29.3), and 4.3% (3.5; 5.4) were reported as CCM, SCM, and ICM, respectively. The CCM ratio varied according to the reason for consultation, with cancer suspicion (52.9% [42.9; 62.8]) and pediatric reasons (38.0% [30.0; 46.6]) showing the lowest CCM percentages. CCM percentages also varied significantly based on the setting where it was performed, ranging from 61.1% (private clinic) to 86.8% (endourology and general hospital). CONCLUSIONS: We show that two-thirds of all urological outpatient cases could be completely managed by telemedicine outside of the pandemic. After the pandemic, it will be important to incorporate telemedicine as an alternative for a patient's first or followup visit, especially those with geographical, pathological, and socioeconomic considerations.

7.
Methods Mol Biol ; 1943: 377-387, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30838630

RESUMEN

Ultrasound-mediated gene delivery is an interesting approach, which could help in increasing gene transfer in deep tissues. Moreover, it allows for performing experiments guided by the image to determine which elements are required. Microbubbles complexed with a eukaryotic expression cassette are excellent agents as they are responsive to ultrasounds and, upon oscillation, can destabilize membranes to enhance gene transfer. Here, we describe the preparation of positively charged microbubbles, plasmid free of antibiotic resistance marker, their combination and the conditions of ultrasound-mediated liver transfection post-systemic administration in mice. This association allowed us to obtain a superior liver gene expression at least over 8 months after a single injection.


Asunto(s)
Microburbujas , Transfección/métodos , Ondas Ultrasónicas , Animales , Permeabilidad de la Membrana Celular/efectos de la radiación , Terapia Genética/métodos , Células HeLa , Humanos , Hígado/citología , Hígado/metabolismo , Hígado/efectos de la radiación , Ratones , Ratones Endogámicos BALB C , Ácidos Nucleicos/genética
9.
Can Urol Assoc J ; 11(6Suppl2): S125-S130, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28616110

RESUMEN

Pelvic organ prolapse (POP) results from weakness or injury of the pelvic floor supports with resulting descent of one or more vaginal compartments (anterior, apical and/or posterior). Women typically become symptomatic from the bulging vaginal wall or related organ dysfunction once this descent reaches the introitus. POP is a common condition, affecting more than half of adult women. Many women presenting to an urologist for stress urinary incontinence or overactive bladder will have associated POP; therefore, it is important for urologists who treat these conditions to be familiar with its diagnosis and management. While POP is part of the core urology training curriculum in some jurisdictions, it is not in Canada.1 This article reviews the diagnosis of POP, including pertinent symptoms to query in the history, important facets of a systematic pelvic examination, and the appropriate use of ancillary tests. Treatment options are also discussed, including conservative measures, pessaries, and various reconstructive and obliterative techniques.

10.
J Control Release ; 262: 170-181, 2017 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-28710005

RESUMEN

Despite the increasing number of clinical trials in gene therapy, no ideal methods still allow non-viral gene transfer in deep tissues such as the liver. We were interested in ultrasound (US)-mediated gene delivery to provide long term liver expression. For this purpose, new positively charged microbubbles were designed and complexed with pFAR4, a highly efficient small length miniplasmid DNA devoid of antibiotic resistance sequence. Sonoporation parameters, such as insonation time, acoustic pressure and duration of plasmid injection were controlled under ultrasound imaging guidance. The optimization of these various parameters was performed by bioluminescence optical imaging of luciferase reporter gene expression in the liver. Mice were injected with 50µg pFAR4-LUC either alone, or complexed with positively charged microbubbles, or co-injected with neutral MicroMarker™ microbubbles, followed by low ultrasound energy application to the liver. Injection of the pFAR4 encoding luciferase alone led to a transient transgene expression that lasted only for two days. The significant luciferase signal obtained with neutral microbubbles decreased over 2days and reached a plateau with a level around 1 log above the signal obtained with pFAR4 alone. With the newly designed positively charged microbubbles, we obtained a much stronger bioluminescence signal which increased over 2days. The 12-fold difference (p<0.05) between MicroMarker™ and our positively charged microbubbles was maintained over a period of 6months. Noteworthy, the positively charged microbubbles led to an improvement of 180-fold (p<0.001) as regard to free pDNA using unfocused ultrasound performed at clinically tolerated ultrasound amplitude. Transient liver damage was observed when using the cationic microbubble-pFAR4 complexes and the optimized sonoporation parameters. Immunohistochemistry analyses were performed to determine the nature of cells transfected. The pFAR4 miniplasmid complexed with cationic microbubbles allowed to transfect mostly hepatocytes compared to its co-injection with MicroMarker™ which transfected more preferentially endothelial cells.


Asunto(s)
ADN/administración & dosificación , Hígado/metabolismo , Microburbujas , Ondas Ultrasónicas , Animales , Técnicas de Transferencia de Gen , Células HeLa , Humanos , Lípidos/química , Hígado/diagnóstico por imagen , Luciferasas/genética , Luciferasas/metabolismo , Ratones Endogámicos BALB C , Plásmidos , Transgenes , Ultrasonografía
11.
Eur Cytokine Netw ; 17(1): 13-8, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16613758

RESUMEN

OBJECTIVES: Interleukin (IL)-10 has anti-atherogenic properties. However, the molecular mechanisms involved in IL-10 protection against atherosclerosis in vivo remain poorly understood. In this study, we examined the effect of IL-10 cDNA in vivo electrotransfer on diet-induced, endothelial activation. METHODS: C57BL/6J mice were fed an atherogenic diet for 10 days. Expression of VCAM-1 and ICAM-1 was examined in the aortic sinus, a region predisposed to atherogenesis in mice, using immunohistochemistry. NF-kappaB activation was examined using a monoclonal antibody that selectively reacts with the activated form of the p65 subunit. RESULTS: We detected a low basal expression of activated NF-kappaB, VCAM-1 and ICAM-1 in the endothelium of the aortic sinus. Endothelial expression of activated NF-kappaB, VCAM-1 and ICAM-1 was markedly increased after 10 days on the atherogenic diet (p < 0.001). In vivo electrotransfer of a murine IL-10-encoding plasmid completely prevented diet-induced endothelial upregulation of activated NF-kappaB, VCAM-1 and ICAM-1 (p < 0.01). CONCLUSION: In vivo electrotransfer of IL-10 cDNA prevents diet-induced endothelial activation. These results suggest that the protective effects of IL-10 may already occur in the very early stages of atherogenesis.


Asunto(s)
Dieta Aterogénica , Endotelio/metabolismo , Molécula 1 de Adhesión Intercelular/biosíntesis , Interleucina-10/metabolismo , FN-kappa B/biosíntesis , Seno Aórtico/metabolismo , Molécula 1 de Adhesión Celular Vascular/biosíntesis , Animales , ADN Complementario , Electroporación , Activación Enzimática , Femenino , Técnicas de Transferencia de Gen , Interleucina-10/genética , Ratones , Ratones Endogámicos C57BL , Regulación hacia Arriba
12.
Ultrasound Med Biol ; 42(2): 624-30, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26653937

RESUMEN

Microbubbles are polydisperse microparticles. Their size distribution cannot be accurately measured from the current methods used, such as optical microscopy, electrical sensing or light scattering. Indeed, these techniques present some limitations when applied to microbubbles, which prompted us to investigate the use of an alternative technique: tunable resistive pulse sensing (TRPS). This technique is based on the principle of the Coulter counter with the advantage of being more flexible compared to other methods using this principle, since the flow rate, the potential difference and the pore size can be modulated. The main limitation of TRPS is that more than one size of nanopore membrane is required to obtain the full size distribution of polydisperse microparticles. To evaluate this technique, the concentration and the size distribution of positively charged microbubbles were studied using TRPS and compared to data obtained using optical microscopy. We describe herein the parameters required for the accurate measurement of microbubble concentration and size distribution by TRPS and present a statistical comparison of the data obtained by TRPS and optical microscopy.


Asunto(s)
Electroquímica/métodos , Lípidos/análisis , Membranas Artificiales , Microburbujas , Nanoporos/ultraestructura , Ultrafiltración/métodos , Campos Electromagnéticos , Electricidad Estática
13.
Clin Nutr ; 35(6): 1291-1300, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27161521

RESUMEN

Immune-enhancing diet (IED) utilization in critically ill septic patients is still debated. A new concept of IED has been proposed combining extra glutamine sequentially with either antioxidants or other amino acids, in order to match patient requirements according to their response to injury. We evaluated whether this new IED elicits a more favorable response to stress when compared with two existing IEDs both enriched in arginine but with different levels of anti-oxidants, in a validated rat model combining head injury (HI) and infectious complications. Forty-eight HI rats were randomized into four groups (n = 11-13 per group) to receive, for 4 days, standard enteral nutrition (S), one of the two existing IEDs (IED1, IED2), or the new IED (IED3; providing glutamine and antioxidants for two days and glutamine and specific amino acids for two days). Two days after HI, the rats received an enteral bolus of luminescent Escherichia coli Xen14 to induce infection, and bacterial dissemination was evaluated. Body weight (BW) was recorded daily. Four days after HI, animals were euthanized; blood was sampled; organs were weighed; cumulated nitrogen balance (CNB) and nitrogen efficiency were determined. IED3 was more efficient than IED1 and IED2 in improving BW recovery from D3 (D3 vs. D1, p < 0.05) after HI. It significantly improved CNB and net protein utilization (IED3 vs. S, IED1, IED2, p < 0.05). An IED with sequential administration of anti-oxidants and glutamine may be better suited to meeting nutritional requirements in severe catabolic states.


Asunto(s)
Traumatismos Craneocerebrales/complicaciones , Dietoterapia/métodos , Inmunidad/fisiología , Infecciones/complicaciones , Prueba de Estudio Conceptual , Aminoácidos/administración & dosificación , Animales , Antioxidantes/administración & dosificación , Traumatismos Craneocerebrales/inmunología , Traumatismos Craneocerebrales/fisiopatología , Modelos Animales de Enfermedad , Nutrición Enteral , Infecciones por Escherichia coli/complicaciones , Infecciones por Escherichia coli/prevención & control , Glutamina/administración & dosificación , Humanos , Control de Infecciones/métodos , Necesidades Nutricionales , Ratas
14.
J Neurosci ; 24(35): 7614-22, 2004 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-15342727

RESUMEN

Protein phosphorylation is crucial for regulating synaptic transmission. We describe a novel mechanism for the phosphorylation of the GABA(A) receptor, which mediates fast inhibition in the brain. A protein copurified and coimmunoprecipitated with the phosphorylated receptor alpha1 subunit; this receptor-associated protein was identified by purification and microsequencing as the key glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH). Molecular constructs demonstrated that GAPDH directly phosphorylates the long intracellular loop of GABA(A) receptor alpha1 subunit at identified serine and threonine residues. GAPDH and the alpha1 subunit were found to be colocalized at the neuronal plasma membrane. In keeping with the GAPDH/GABA(A) receptor molecular association, glycolytic ATP produced locally at plasma membranes was consumed for this alpha1 subunit phosphorylation, possibly within a single macrocomplex. The membrane-attached GAPDH is thus a dual-purpose enzyme, a glycolytic dehydrogenase, and a receptor-associated kinase. In acutely dissociated cortical neurons, the rundown of the GABA(A) responses was essentially attributable to a Mg(2+)-dependent phosphatase activity, which was sensitive to vanadate but insensitive to okadaic acid or fluoride. Rundown was significantly reduced by the addition of GAPDH or its reduced cofactor NADH and nearly abolished by the addition of its substrate glyceraldehyde-3-phosphate (G3P). The prevention of rundown by G3P was abolished by iodoacetamide, an inhibitor of the dehydrogenase activity of GAPDH, indicating that the GABA(A) responses are maintained by a glycolysis-dependent phosphorylation. Our results provide a molecular mechanism for the direct involvement of glycolysis in neurotransmission.


Asunto(s)
Gliceraldehído-3-Fosfato Deshidrogenasas/fisiología , Glucólisis/fisiología , Neuronas/efectos de los fármacos , Procesamiento Proteico-Postraduccional/efectos de los fármacos , Proteínas Serina-Treonina Quinasas/fisiología , Receptores de GABA-A/metabolismo , Transmisión Sináptica/efectos de los fármacos , Adenosina Difosfato/farmacología , Secuencia de Aminoácidos , Animales , Química Encefálica , Células COS , Bovinos , Membrana Celular/efectos de los fármacos , Membrana Celular/enzimología , Chlorocebus aethiops , Difosfatos/farmacología , Gliceraldehído 3-Fosfato/farmacología , Gliceraldehído-3-Fosfato Deshidrogenasas/antagonistas & inhibidores , Gliceraldehído-3-Fosfato Deshidrogenasas/aislamiento & purificación , Gliceraldehído-3-Fosfato Deshidrogenasas/farmacología , Hipocampo/citología , Yodoacetamida/farmacología , Magnesio/farmacología , Datos de Secuencia Molecular , NAD/farmacología , Neuronas/enzimología , Fosforilación/efectos de los fármacos , Mapeo de Interacción de Proteínas , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/aislamiento & purificación , Conejos , Ratas , Ratas Sprague-Dawley , Receptores de GABA-A/genética , Proteínas Recombinantes de Fusión/metabolismo , Transmisión Sináptica/fisiología , Transfección
15.
Hum Gene Ther ; 16(10): 1194-201, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16218780

RESUMEN

Efficient DNA electrotransfer can be achieved with combinations of short high-voltage (HV) and long low voltage (LV) pulses that cover two effects of the pulses, namely, target cell electropermeabilization and DNA electrophoresis within the tissue. Because HV and LV can be delivered with a lag up to 3000 sec between them, we considered that it was possible to analyze separately the respective importance of the two types of effects of the electric fields on DNA electrotransfer efficiency. The tibialis cranialis muscles of C57BL/6 mice were injected with plasmid DNA encoding luciferase or green fluorescent protein and then exposed to various combinations of HV and LV pulses. DNA electrotransfer efficacy was determined by measuring luciferase activity in the treated muscles. We found that for effective DNA electrotransfer into skeletal muscles the HV pulse is prerequisite; however, its number and duration do not significantly affect electrotransfer efficacy. DNA electrotransfer efficacy is dependent mainly on the parameters of the LV pulse(s). We report that different LV number, LV individual duration, and LV strength can be used, provided the total duration and field strength result in convenient electrophoretic transport of DNA toward and/or across a permeabilized membrane.


Asunto(s)
ADN , Electroporación , Técnicas de Transferencia de Gen , Músculo Esquelético , Animales , ADN/administración & dosificación , ADN/genética , Electroporación/métodos , Femenino , Marcadores Genéticos/genética , Proteínas Fluorescentes Verdes/biosíntesis , Proteínas Fluorescentes Verdes/genética , Luciferasas/biosíntesis , Luciferasas/genética , Ratones , Músculo Esquelético/metabolismo
16.
Curr Opin Biotechnol ; 13(5): 443-7, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12459335

RESUMEN

In vivo electrotransfer is a physical technique for gene delivery in various mammalian tissues, which involves the injection of plasmid DNA into a target tissue and administration of an electric field. Its ease of performance, as well as recent understanding of its mechanism and applications to different mammalian tissues such as skeletal muscle, liver, brain and tumors, makes it a powerful technique. It could be used in gene therapy and as a laboratory tool to study gene functions.


Asunto(s)
Electroporación/métodos , Regulación de la Expresión Génica/fisiología , Técnicas de Transferencia de Gen , Terapia Genética/métodos , Neoplasias/terapia , Plásmidos/química , Plásmidos/metabolismo , Animales , ADN , Campos Electromagnéticos , Electroforesis/métodos , Perfilación de la Expresión Génica/métodos , Humanos , Músculo Esquelético/fisiología , Plásmidos/genética
17.
Can Urol Assoc J ; 9(9-10): E613-7, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26425223

RESUMEN

INTRODUCTION: Ketamine is a common recreational drug. Severe lower urinary tract symptoms associated with its consumption have been reported, but little is known about the involved mechanisms. The effect of ketamine, which is excreted in urine, was evaluated by its application on an in vitro three-dimensional human tissue-engineered bladder model composed of an urothelium and a submucosa. METHODS: Human urothelial cells were cultured with medium containing various concentrations of ketamine and harvested at different times to obtain growth curves. Using this model, specific activity of caspase-3 was measured to assess the level of apoptosis induced by ketamine. Finally, a human tissue-engineered bladder model was used. Urothelial cells were plated on a stromal layer made of dermal fibroblasts and incubated at the air/liquid interface to allow their differentiation. Ketamine was then put on the mature urothelium using paper or agarose vectors for 48 hours. RESULTS: The presence of ketamine increased cells' doubling times from 1.26 days for control to 1.38 days (p = 0.14) and 1.78 days (p < 0.01) for the 0.5 mM and 1.5 mM concentrations, respectively. 5 mM and 10 mM of ketamine led to decline in the major cell population. Exposure to 5 mM ketamine induced apoptosis, confirmed by a 2.5-fold increase in capase-3 specific activity from control (p = 0.03). The structure and cellular cohesion of the urothelium on the three-dimensional model, especially in the intermediate layers, were severely affected in a concentration dependant fashion with both vectors. CONCLUSION: The presence of ketamine in the bladder directly damages the urothelium through the induction of apoptosis.

18.
Technol Cancer Res Treat ; 1(5): 351-4, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12625760

RESUMEN

The use of electric pulses to transfect cells has recently been extended to show the utility of this procedure in vivo. Electrotransfer has been performed in vivo on several tissue types including skin, blood vessels, liver, tumor, muscle, cornea, brain and spleen. The most widely targeted tissue has been skeletal muscle. In addition to its potential use in gene therapy, in vivo DNA electrotransfer is also, because of its simplicity, a powerful laboratory tool to study in vivo gene expression and function in a given tissue. Many published studies have now shown that plasmid electrotransfer can lead to a long-lasting therapeutic effect in various pathologies, such as cancer, blood disease, or muscle ischemia. The future potential for this gene therapy approach will include delivery for both local action or distal effect by secretion of the transgenic proteins in the circulation.


Asunto(s)
Electroporación/métodos , Terapia Genética/métodos , Animales , Animales Modificados Genéticamente , ADN/metabolismo , Humanos , Músculo Esquelético/metabolismo , Neoplasias/terapia , Plásmidos/metabolismo , Transfección
19.
Acta Neurol Belg ; 114(3): 167-78, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24915752

RESUMEN

Natalizumab (Tysabri(®)) is highly efficacious in controlling disease activity in relapsing multiple sclerosis (MS) patients. As it is one of the more recent therapies for MS, there remains a need for long-term safety and efficacy data of natalizumab in a clinical practice setting. The Tysabri observational program (TOP) is an open-label, multicenter, multinational, prospective observational study, aiming to recruit up to 6,000 patients with relapsing-remitting MS from Europe, Canada and Australia. The objectives of this study are to collect long-term safety and efficacy data on disease activity and disability progression. We report here the interim results of the 563 patients included in TOP between December 2007 and 2012 from Belgium. This patient cohort was older at baseline, had longer disease duration, higher neurological impairment, and a higher baseline annualized relapse rate, when compared to patients included in the pivotal phase III AFFIRM trial. Nevertheless, the efficacy of natalizumab was comparable. The annualized relapse rate on treatment was reduced by 90.70 % (p < 0.0001) with a cumulative probability of relapse of 26.87 % at 24 months. The cumulative probabilities of sustained disability improvement and progression at 24 months were 25.68 and 9.01 %, respectively. There were no new safety concerns over the follow-up period. Two cases of progressive multifocal leukoencephalopathy were diagnosed. Our results are consistent with other observational studies in the post-marketing setting.


Asunto(s)
Anticuerpos Monoclonales Humanizados/uso terapéutico , Factores Inmunológicos/uso terapéutico , Esclerosis Múltiple/tratamiento farmacológico , Adolescente , Adulto , Distribución por Edad , Anciano , Bélgica/epidemiología , Estudios de Cohortes , Evaluación de la Discapacidad , Femenino , Humanos , Cooperación Internacional , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Natalizumab , Vigilancia de Productos Comercializados , Índice de Severidad de la Enfermedad , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
20.
ACS Nano ; 7(6): 4954-66, 2013 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-23641799

RESUMEN

Cell-released vesicles are natural carriers that circulate in body fluids and transport biological agents to distal cells. As nature uses vesicles in cell communication to promote tumor progression, we propose to harness their unique properties and exploit these biogenic carriers as Trojan horses to deliver therapeutic payloads to cancer cells. In a theranostic approach, cell-released vesicles were engineered by a top-down procedure from precursor cells, previously loaded with a photosensitizer and magnetic nanoparticles. The double exogenous cargo provided vesicles with magnetic and optical responsiveness allowing therapeutic and imaging functions. This new class of cell-derived smart nanovectors was named "theranosomes". Theranosomes enabled efficient photodynamic tumor therapy in a murine cancer model in vivo. Moreover the distribution of this biogenic vector could be monitored by dual-mode imaging, combining fluorescence and MRI. This study reports the first success in translating a cell communication mediator into a smart theranostic nanovector.


Asunto(s)
Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Imanes , Nanoestructuras , Neoplasias de la Próstata/patología , Neoplasias del Cuello Uterino/patología , Animales , Membrana Celular/metabolismo , Femenino , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Imagen por Resonancia Magnética , Masculino , Mesoporfirinas/química , Mesoporfirinas/uso terapéutico , Ratones , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/uso terapéutico , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/terapia , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/terapia
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