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1.
J Oncol Pharm Pract ; 25(5): 1089-1098, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29726786

RESUMEN

PURPOSE: The aim of this study was to monitor environmental contamination by 10 antineoplastic drugs in Canadian oncology pharmacy and patient care areas. The secondary objective was to explore the impact of factors that may explain contamination. METHODS: Twelve standardized sites were sampled in each center (six in the pharmacy and six in patient care areas). Each sample was prepared to allow quantification of seven antineoplastic drugs (cyclophosphamide, ifosfamide, methotrexate, cytarabine, gemcitabine, 5-fluorouracil, irinotecan) by UPLC-MS-MS. Docetaxel, paclitaxel and vinorelbine were also detected, but not quantified due to sensibility limitations. The impact of some factors was evaluated compared with a Kolmogorov-Smirnov test for independent samples. RESULTS: Eighty-three Canadian centers were recruited in 2017. A total of 953 surfaces were sampled, 495 in pharmacy and 458 in patient care areas. Cyclophosphamide was most often found on surfaces (36% of samples positive, 75th percentile 0.0040 ng/cm2). The arm rest (81.7% of samples positive for at least one antineoplastic drug), the front grille inside the hood (78.3%) and the floor in front of the hood (61.4%) were more frequently contaminated. Centers who prepared more antineoplastic drugs per year had higher concentration on different surfaces ( p < 0.0001). CONCLUSION: Despite growing awareness and implementation of new safe handling guidelines, healthcare centers' surfaces remain contaminated with traces of many antineoplastic drugs. The use of personal protective equipment remains indisputable. Performing an annual monitoring remains a good indicator to monitor trends over time and to compare with similar centers.


Asunto(s)
Antineoplásicos/análisis , Contaminación de Medicamentos , Monitoreo del Ambiente/métodos , Canadá , Cromatografía Liquida/métodos , Contaminación de Equipos , Humanos , Exposición Profesional/análisis , Farmacias , Espectrometría de Masas en Tándem/métodos
2.
J Hum Nutr Diet ; 32(4): 531-534, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30916423

RESUMEN

BACKGROUND: Monitoring activity-related energy expenditure (EE) is essential in the management of daily activity and the dietary programme in patients with type 2 diabetes (T2D) and must be estimated accurately. Accelerometry-based equations have frequently used to estimate EE, although the validity of these methods has not been confirmed in patients with T2D. The present study aimed to test the validity of an accelerometry-based method (Bouten's method) to assess EE during walking in patients with T2D. METHODS: The study included 20 patients with controlled T2D [mean (SD) duration: 10.6 (6.1) years; age: 57.5 (8.4) years; body mass index: 26.4 (2.6) kg m- ²]. All participants performed five 6-min periods of walking at different speeds (0.5-1.5 m s-1 ) on a treadmill. Mechanical data were recorded using an inertial measurement unit placed on the lower back with gas exchange being simultaneously monitored. RESULTS: Values of EE during walking estimated by the accelerometer method did not differ significantly from those measured by indirect calorimetry. Bias and root mean square error were -1.17 and 2.93 kJ min-1 , respectively, on average across speeds. CONCLUSIONS: Our results suggest that EE during walking may be accurately estimated in patients with diabetes mellitus using an accelerometer.


Asunto(s)
Acelerometría/estadística & datos numéricos , Calorimetría Indirecta/estadística & datos numéricos , Diabetes Mellitus Tipo 2/fisiopatología , Metabolismo Energético , Prueba de Paso/estadística & datos numéricos , Acelerometría/métodos , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Prueba de Paso/métodos , Caminata
3.
J Occup Environ Hyg ; 14(8): 661-669, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28574754

RESUMEN

PURPOSE: Oncology workers are occupationally exposed to antineoplastic drugs. This exposure can induce adverse health effects. To reduce their exposure, contamination on surfaces should be kept as low as possible. The main objective of this study was to monitor environmental contamination with cyclophosphamide, ifosfamide, and methotrexate in oncology pharmacy and patient care areas in Canadian centers. The secondary objective was to describe the impact of some factors that may limit contamination. METHODS: This is a descriptive study. Twelve standardized sites were sampled in each participating center (six in the pharmacy and six in patient care areas). Samples were analyzed for the presence of cyclophosphamide, ifosfamide, and methotrexate by ultra-performance liquid chromatography-tandem mass spectrometry technology. Descriptive statistical analyses were done and results were compared with a Kolmogorov-Smirnov test for independent samples. RESULTS: In 2016, 66 centers participated in this study (66/202, 32.7%). Overall, 43.4% (326/752) of the samples were positive for cyclophosphamide, 13.2% (99/752) for ifosfamide and 6.9% (52/752) for methotrexate. The 75th percentile value of cyclophosphamide surface concentration was 6.8 pg/cm2 and lower than the limit of detection for ifosfamide and methotrexate. Centers who prepared more antineoplastic drugs per year (p < 0.0001), who used more cyclophosphamide per year (p < 0.0001) and who primed antineoplastic IV tubing in patient care unit by nurses (p = 0.004) showed significantly higher surface contamination to cyclophosphamide. CONCLUSION: Environmental surveillance is one part of a comprehensive approach for minimizing hazardous exposures in healthcare. This study highlights a low level of contamination of three hazardous drugs amongst 66 Canadian centers. Regular environmental monitoring is a good practice to maintain contamination as low as reasonably achievable.


Asunto(s)
Antineoplásicos/análisis , Ciclofosfamida/análisis , Monitoreo del Ambiente/normas , Hospitales/estadística & datos numéricos , Ifosfamida/análisis , Metotrexato/análisis , Exposición Profesional/análisis , Canadá , Contaminación de Equipos , Humanos , Servicio de Oncología en Hospital , Servicio de Farmacia en Hospital
4.
J Occup Environ Hyg ; 12(2): 87-94, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25105559

RESUMEN

No occupational exposure limit exists for antineoplastic drugs. The main objective of this study was to describe environmental contamination with cyclophosphamide, ifosfamide, and methotrexate in pharmacy and patient care areas of Canadian hospitals in 2013. The secondary objective was to compare the 2013 environmental monitoring results with previous studies. Six standardized sites in the pharmacy and six sites on patient care areas were sampled in each participating center. Samples were analyzed for the presence of cyclophosphamide, ifosfamide, and methotrexate by UPLC-MSMS. The limit of detection (LOD) in pg/cm(2) was 1.8 for cyclophosphamide, 2.2 for ifosfamide, and 7.5 for methotrexate. The 75th percentile of cyclophosphamide concentration was compared between the 2013, 2008-2010, and 2012 studies. Thirty-six hospitals participated in the study and 422 samples were collected. Overall, 47% (198/422) of the samples were positive for cyclophosphamide, 18% (75/422) were positive for ifosfamide, and 3% (11/422) were positive for methotrexate. In 2013, the 75th percentile value of cyclophosphamide surface concentration was reduced to 8.4pg/cm(2) (n = 36), compared with 9.4pg/cm(2) in 2012 (n = 33) and 40pg/cm(2) (n = 25) in 2008-2010. The 75th percentile for ifosfamide and methotrexate concentration remained lower than the LOD. The 2013 study shows an improvement in the surface contamination level, and a plateau effect in the proportion of positive samples.


Asunto(s)
Antineoplásicos/análisis , Monitoreo del Ambiente , Contaminantes Ambientales/análisis , Hospitales , Servicio de Farmacia en Hospital , Ciclofosfamida/análisis , Composición de Medicamentos/métodos , Estudios de Seguimiento , Ifosfamida/análisis , Metotrexato/análisis , Exposición Profesional/análisis , Quebec
5.
Opt Lett ; 38(2): 127-9, 2013 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-23454937

RESUMEN

We report the first demonstration of a Raman fiber laser (RFL) emitting in the mid-infrared, above 3 µm. The operation of a single-mode As2S3 chalcogenide glass based RFL at 3.34 µm is demonstrated by using a low-loss Fabry-Pérot cavity formed by a pair of fiber Bragg gratings. A specially designed quasi-cw erbium-doped fluoride fiber laser emitting at 3.005 µm is used to pump the RFL. A laser output peak power of 0.6 W is obtained with a lasing efficiency of 39% with respect to the launched pump power.

6.
Arch Pediatr ; 28(8): 683-688, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34690027

RESUMEN

BACKGROUND: Neonatal bacterial infections must be bacteriologically confirmed from laboratory samples to best adjust antibiotic therapy. Lumbar puncture (LP) has been recommended for infants younger than 1 month with suspected serious bacterial infection (SBI) to manage possible meningitis. However, the incidence of bacterial meningitis associated with other infections and particularly with urinary tract infections (UTIs) is low. Recourse to systematic LP may be less essential if infants have a UTI. We aimed (a) to determine the management and frequency of bacterial meningitis coexisting with a documented diagnosis of UTI in infants aged < 1 month who had an LP, and (b) to evaluate the management of infants in emergency admissions with suspected SBI while assessing antibiotic treatment. METHODS: We conducted a retrospective single-center study from January 2010 to April 2019 including all cases of neonatal bacterial infections, and collected data on the clinical, laboratory, and radiological features. RESULTS: In all, 409 infants were included in the study. Of these, 162 (39.6%) presented with a UTI and eight (2%) had bacterial meningitis. Of the infants diagnosed with UTI, 74.7% had an LP, of whom 34.7% experienced LP complications. No coexistence of UTI and bacterial meningitis was found among infants who had an LP and a documented UTI. CONCLUSION: Although not all infants had an LP and a urine culture at the same time, these results show that bacterial meningitis coexisting with a confirmed UTI diagnosis in infants is rare. Furthermore, LP can be traumatic in some cases and therefore its utility should be assessed according to the clinical context.


Asunto(s)
Servicio de Urgencia en Hospital/normas , Punción Espinal/normas , Infecciones Urinarias/diagnóstico , Antibacterianos/administración & dosificación , Antibacterianos/uso terapéutico , Manejo de la Enfermedad , Servicio de Urgencia en Hospital/organización & administración , Servicio de Urgencia en Hospital/estadística & datos numéricos , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Estudios Retrospectivos , Punción Espinal/métodos , Punción Espinal/estadística & datos numéricos , Infecciones Urinarias/terapia
8.
J Cell Biol ; 152(2): 335-48, 2001 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-11266450

RESUMEN

Duchenne muscular dystrophy is a lethal recessive disease characterized by widespread muscle damage throughout the body. This increases the difficulty of cell or gene therapy based on direct injections into muscles. One way to circumvent this obstacle would be to use circulating cells capable of homing to the sites of lesions. Here, we showed that stem cell antigen 1 (Sca-1), CD34 double-positive cells purified from the muscle tissues of newborn mice are multipotent in vitro and can undergo both myogenic and multimyeloid differentiation. These muscle-derived stem cells were isolated from newborn mice expressing the LacZ gene under the control of the muscle-specific desmin or troponin I promoter and injected into arterial circulation of the hindlimb of mdx mice. The ability of these cells to interact and firmly adhere to endothelium in mdx muscles microcirculation was demonstrated by intravital microscopy after an intraarterial injection. Donor Sca-1, CD34 muscle-derived stem cells were able to migrate from the circulation into host muscle tissues. Histochemical analysis showed colocalization of LacZ and dystrophin expression in all muscles of the injected hindlimb in all of five out of five 8-wk-old treated mdx mice. Their participation in the formation of muscle fibers was significantly increased by muscle damage done 48 h after their intraarterial injection, as indicated by the presence of 12% beta-galactosidase-positive fibers in muscle cross sections. Normal dystrophin transcripts detected enzymes in the muscles of the hind limb injected intraarterially by the mdx reverse transcription polymerase chain reaction method, which differentiates between normal and mdx message. Our results showed that the muscle-derived stem cells first attach to the capillaries of the muscles and then participate in regeneration after muscle damage.


Asunto(s)
Trasplante de Células/métodos , Distrofina/genética , Células Madre Hematopoyéticas/fisiología , Músculo Esquelético/citología , Distrofia Muscular Animal/terapia , Actinas/análisis , Animales , Animales Recién Nacidos , Antígenos CD34/análisis , Antígenos Ly/análisis , Adhesión Celular , Diferenciación Celular , Línea Celular , Distrofina/análisis , Endotelio Vascular/fisiología , Terapia Genética , Células Madre Hematopoyéticas/citología , Miembro Posterior , Inmunofenotipificación , Inyecciones Intraarteriales , Proteínas de la Membrana/análisis , Ratones , Ratones Endogámicos mdx , Ratones Transgénicos , Microcirculación/fisiología , Fibras Musculares Esqueléticas/citología , Fibras Musculares Esqueléticas/fisiología , Miosinas/análisis , Transcripción Genética , beta-Galactosidasa/análisis , beta-Galactosidasa/genética
9.
Cancer Res ; 37(7 Pt 1): 1953-5, 1977 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-861931

RESUMEN

Drug combinations of 9-beta-D-arabinofuranosyladenine and 2'-deoxycoformycin were active in the therapy of mice with intracerebral implants of the L1210 tumor. In in vivo mouse brain adenosine deaminase studies, inhibition of 9-beta-D-arabinofuranosyladenine deamination for periods of up to 24 hr was found after a single i.p. dose of 0.002 mmole/kg.


Asunto(s)
Inhibidores de la Adenosina Desaminasa , Antineoplásicos/uso terapéutico , Azepinas/uso terapéutico , Neoplasias Encefálicas/tratamiento farmacológico , Desoxirribonucleósidos/uso terapéutico , Leucemia L1210/tratamiento farmacológico , Nucleósido Desaminasas/antagonistas & inhibidores , Vidarabina/uso terapéutico , Animales , Quimioterapia Combinada , Femenino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos DBA , Vidarabina/administración & dosificación , Vidarabina/farmacología
10.
Cancer Res ; 37(9): 3274-9, 1977 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-884674

RESUMEN

The triple combination of 2'-deoxycoformycin (2'-dCF), 9-beta-D-arabinofuranosyladenine 5'-phosphate, and 9-beta-D-arabinofuranosylcytosine was found to be very effective in the therapy of C57BL X DBA/2 F1 mice with intracerebral L1210. At the dosages and dosage scheduling used, the double combination of 2'-dCF and 9-beta-D-arabinofuranosyladenine 5'-phosphate gave minimal but significant increases in life-span. When 9-beta-D-arabinofuranosylcytosine was given at suboptimal dosage to mice with intracerebral L1210, the host toxicity caused by 2'-dCF and 9-beta-D-arabinofuranosyladenine 5'-phosphate in combination was decreased by a factor of 2, allowing a more prolonged therapy. "Cures" were obtained with the triple combination at dosages of 9-beta-D-arabinofuranosylcytosine that did not "cure". The supernatant adenosine deaminase from C57BL X DBA/2 F1 mouse brains was purified and the Ki for 2'-dCF using 9-beta-D-arabinofuranosyladenine as substrate was determined to be not more than 2 X 10(-11) M.


Asunto(s)
Antineoplásicos/uso terapéutico , Azepinas/uso terapéutico , Neoplasias Encefálicas/tratamiento farmacológico , Citarabina/uso terapéutico , Desoxirribonucleótidos/uso terapéutico , Leucemia L1210/tratamiento farmacológico , Vidarabina/análogos & derivados , Adenosina Desaminasa/metabolismo , Inhibidores de la Adenosina Desaminasa , Animales , Antineoplásicos/efectos adversos , Peso Corporal/efectos de los fármacos , Encéfalo/enzimología , Citarabina/efectos adversos , Sinergismo Farmacológico , Quimioterapia Combinada , Femenino , Técnicas In Vitro , Cinética , Ratones , Ratones Endogámicos DBA , Vidarabina/efectos adversos , Vidarabina/uso terapéutico
11.
J Med Chem ; 23(3): 300-4, 1980 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7365745

RESUMEN

Fourteen phosphorylated acetals and aldehydes were synthesized for testing in vitro as inhibitors or substrates of aldehyde oxidase, an enzyme involved in the conversion of aldophosphamide to inactive carboxyphosphamide, and for concurrent in vivo administration with cyclophosphamide to mice bearing L1210 ascites tumor cells. Five phosphorus derivatives gave Ki values of 0.1--0.3 mM compared to 0.03 mM for pyridoxal, as determined in aldehyde oxidase assays using N-methylnicotinamide as the substrate. The most active phosphorus inhibitor, ethyl phenyl(2-formylethyl)phosphinate (2b), and pyridoxal were further shown to give competitive and mixed inhibition, respectively. Three aldehydes, administered concurrently with cyclophosphamide, produced greater increases in life span of L1210-implanted mice than did pyridoxal. All four agents gave an average increase in life span greater than 50% over that shown by cyclophosphamide alone.


Asunto(s)
Acetales/farmacología , Aldehído Oxidorreductasas/antagonistas & inhibidores , Aldehídos/farmacología , Ciclofosfamida/farmacología , Acetales/síntesis química , Aldehídos/síntesis química , Animales , Sinergismo Farmacológico , Femenino , Técnicas In Vitro , Cinética , Leucemia L1210/tratamiento farmacológico , Hígado/enzimología , Ratones , Conejos , Relación Estructura-Actividad
12.
Transplantation ; 72(1): 38-44, 2001 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-11468532

RESUMEN

BACKGROUND: Overcoming adverse effects of immunosuppressors can be achieved by combining different drugs, thus allowing a dosage reduction. Myoblast transplantation is a potential therapy for Duchenne muscular dystrophy. Our research group previously established that FK506 (tacrolimus) is an effective immunosuppressive drug for myoblast transplantation in mice and monkeys. METHODS: In the present study, a reduced dose of FK506 at 1.0 mg/kg/day was used in combination with mycophenolate mofetil (MMF; 80 mg/kg/day) as an immunosuppressive protocol for myoblast transplantation. Graft success was evaluated by quantifying the number of dystrophin-positive fibers per muscle section that were injected with normal cells. RESULTS: MMF used alone could not prevent immune rejection of the transplanted myoblasts. MMF given in combination with FK506 immediately after transplantation reduced the success of myoblast transplantation by about 50%. A low dose of FK506 combined with MMF after the establishment of the graft (3 weeks) maintained graft success and controlled immune infiltration compared with a low dose of FK506 alone. However, lymphocyte infiltration was observed at longer term using a low dose of FK506 combined with MMF. CONCLUSIONS: The diminution of graft success when combining FK506 and MMF by the time of myoblast transplantation could be attributed to the inhibition of myoblast fusion by MMF. The use of MMF and FK506 after the establishment of the graft did not reduce graft success, however, this combination was not effective at controlling long-term immune rejection in comparison with the optimal dose of FK506 alone.


Asunto(s)
Trasplante de Células , Inmunosupresores/uso terapéutico , Músculo Esquelético/citología , Ácido Micofenólico/uso terapéutico , Tacrolimus/uso terapéutico , Animales , División Celular/efectos de los fármacos , Fusión Celular , Células Cultivadas , Relación Dosis-Respuesta a Droga , Sinergismo Farmacológico , Quimioterapia Combinada , Rechazo de Injerto/prevención & control , Supervivencia de Injerto/efectos de los fármacos , Sistema Inmunológico/patología , Inmunosupresores/administración & dosificación , Ratones , Ratones Endogámicos , Ratones Endogámicos mdx , Ratones Transgénicos , Músculo Esquelético/patología , Ácido Micofenólico/análogos & derivados , Tacrolimus/administración & dosificación
13.
Chest ; 106(6): 1917-8, 1994 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7988231

RESUMEN

Despite improved technology, central venous catheters are associated with many complications that occur usually within 48 h of placement. We report a 42-year-old man with a rare erosion of a venous catheter (Silastic) into a bronchus 2 years after its insertion.


Asunto(s)
Bronquios/lesiones , Cateterismo Venoso Central/efectos adversos , Catéteres de Permanencia/efectos adversos , Adulto , Broncografía , Humanos , Venas Yugulares , Masculino , Heridas Penetrantes/etiología
14.
DNA Cell Biol ; 19(7): 421-9, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10945232

RESUMEN

It is now well established that the HMG box DNA-binding motif can alter the topology of double-stranded DNA in several ways. Using the spermatid-specific tsHMG as a model protein of the HMG-1/-2 family, we have demonstrated that its expression in E. coli produces an increase in plasmid supercoiling density that is likely a consequence of its ability to constrain free supercoils in vivo. As demonstrated in vitro, stabilization of free DNA supercoils by tsHMG prevents topoisomerase I from gaining access to the template and could represent a mechanism for the apparent inhibition of topoisomerase I in bacteria. A similar modulation of eukaryotic topoisomerase I activity was not detected after expression of the tsHMG in mammalian cells. This differential response is discussed in terms of the marked difference in DNA packaging and accessibility of free supercoils in prokaryotic vs. eukaryotic cells.


Asunto(s)
ADN-Topoisomerasas de Tipo I/metabolismo , Escherichia coli/metabolismo , Proteínas del Grupo de Alta Movilidad/metabolismo , Línea Celular , Replicación del ADN , ADN Superhelicoidal/genética , ADN Superhelicoidal/metabolismo , Escherichia coli/genética , Células Eucariotas/citología , Células Eucariotas/metabolismo , Genes Reporteros/genética , Proteínas del Grupo de Alta Movilidad/genética , Humanos , Plásmidos/genética , Unión Proteica , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo
15.
Cell Transplant ; 8(5): 465-76, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10580341

RESUMEN

The success of myoblast transplantation in clinical trials has been limited in part by the low dispersion of grafted cells outside the injection site. Our research group previously reported that the culture of myoblasts with concanavalin A, a stimulator of metalloproteinase production, increased their migration. Several lines of evidence also suggested that muscle cell fusion involves metalloproteinase-sensitive mechanisms. To determine whether the increased expression of metalloproteinases had an influence on myoblast fusion and dispersion through the muscle following transplantation, we generated a myoblast cell line expressing human matrilysin (MMP-7). The MMP-7-expressing myoblasts were obtained by the stable transfection of a matrilysin expression vector in a TnILacZ immortomouse myoblast clone. Matrilysin-expressing myoblasts showed a highly increased in vitro fusion index, forming seven times (p < 0.001) more myotubes than the control cell line and three times (p < 0.001) more myotubes than the Immortomyoblast parental clone. Single-site transplantation of matrilysin-expressing myoblasts generated more fibers (p < 0.001), over a greater surface (p < 0.001) than the control cell line. The cotransplantation of matrilysin-expressing myoblasts and of normal human myoblasts in SCID mice increased the number of human dystrophin-positive fibers and myotubes by sixfold. Although no significant increased migration of myoblasts outside the injection sites was observed, our results show that the metalloproteinase activity can improve the myogenic potential of myoblasts in vitro and the fusion of myoblasts with host fibers in vivo. MMP-7 expression may be useful in increasing myoblast transplantation success.


Asunto(s)
Trasplante de Células/métodos , Metaloproteinasa 7 de la Matriz/genética , Músculo Esquelético/citología , Animales , Línea Celular , Células Cultivadas , Distrofina/biosíntesis , Distrofina/genética , Femenino , Humanos , Metaloproteinasa 7 de la Matriz/biosíntesis , Ratones , Ratones Endogámicos BALB C , Ratones SCID , Músculo Esquelético/metabolismo , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , beta-Galactosidasa/análisis , beta-Galactosidasa/genética
16.
Cell Transplant ; 9(4): 539-49, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11038070

RESUMEN

The effect of pretreatments of host muscles with metalloproteinases (MMPs) or with notexin on the migration of transplanted myoblasts was investigated. Transgenic TnILacZ mice in which the beta-galactosidase gene is under the control of a quail fast skeletal troponin I gene promoter were used as donors. A polyethylene microtube with four perforations was inserted in the tibialis anterior (TA) of CD1 mice. Both pretreatment substances and cells were slowly injected through that microtube. Muscles were pretreated 2 days before myoblast injection either with a mixture of collagenase, matrilysin, and notexin or with only collagenase and matrilysin or only notexin. As control for our experiments, TnILacZ and C2C12 myoblasts were also injected in TA muscles not pretreated. Comparison of short and long-term myoblast radial migration was performed using a dye (PKH26) and X-gal staining, respectively. The recipient mice were immunosuppressed with FK506. Two days after myoblast transplantation, the cell movement in muscles pretreated with collagenase, matrilysin, and notexin was slightly greater than in muscles pretreated only with collagenase and matrilysin but was about twice that observed in muscles treated with notexin alone. Almost no radial migration of TnILacZ myoblasts was observed in untreated muscles. The C2C12 myoblasts showed a four-to fivefold higher migration capacity than TnILacZ myoblasts. At 15 days after TnILacZ myoblast transplantation, the farthest positive beta-gal muscle fibers show a two- to threefold extension of the initial migration observed at 2 days, demonstrating the ability of myoblasts to continue the migration following all pretreatments and even in the untreated muscles. In addition, more muscle fibers expressed the beta-gal reporter gene in muscles pretreated only with MMPs. Our results clearly demonstrate that muscle pretreatments with MMPs increase myoblast migration and fusion with host muscle fibers after transplantation and that the C2C12 cell line producing MMPs has a higher migratory capacity.


Asunto(s)
Movimiento Celular , Trasplante de Células , Metaloendopeptidasas/metabolismo , Músculos/citología , Músculos/trasplante , Animales , Células Cultivadas , Colagenasas/metabolismo , Venenos Elapídicos/farmacología , Genes Reporteros , Metaloproteinasa 7 de la Matriz/metabolismo , Ratones , Ratones Transgénicos , Músculos/efectos de los fármacos , Músculos/metabolismo , Neurotoxinas/farmacología , ARN/metabolismo , Transfección , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/metabolismo
17.
Cell Transplant ; 12(1): 91-100, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12693669

RESUMEN

Migration of transplanted myogenic cells occurs during both embryogenesis and regeneration of skeletal muscles and is important for successful myoblast transplantation, but little is known about factors that promote chemotaxis of these cells. Tumor necrosis factor-alpha (TNF-alpha) is known to induce chemotactic effect on several cell types. In this study, we investigated its influence on the in vitro and in vivo motility of C2C12 and primary myoblasts. In the in vitro test performed in the blind-well Boyden chambers, we showed that TNF-alpha (50-400 U/ml) significantly enhanced the ability of myogenic cells to migrate. The dose-response curve for this factor was bell shaped, with maximum activity in the 200 U/ml range. In the in vivo test, intramuscular administration of TNF-alpha was performed by an Alzet pump connected to a perforated polyethylene microtube inserted in the tibialis anterior (TA) of CD1 mice. In these experiments, myoblasts were injected under the muscle epimysium. The recipient mice were immunosuppressed with FK506. Our results showed that, 5 days after myoblast transplantation, cells migrated further in the muscles infused with TNF-alpha than in the muscles not exposed to TNF-alpha. TNF-alpha not only has a chemotactic activity but may also modify cell migration via its action on matrix metalloproteinase (MMP) expression. The proteolytic activities of the MMPs secreted in the muscles were thus also assessed by gelatin zymography. The results showed an increased of MMP-2 and MMP-9 transcripts in the TNF-alpha-infused muscles injected with myogenic cells. Myoblast migration during transplantation may be enhanced by overlapping gradients of several effector molecules such as TNF-alpha, interferon-gamma (INF-gamma), and interleukins, released at the site of muscle injury. We propose that TNF-alpha may promote myoblast migration directly through chemotactic activity and indirectly by enhancing MMP activity at the site of muscle injury.


Asunto(s)
Diferenciación Celular/fisiología , Quimiotaxis/fisiología , Músculo Esquelético/metabolismo , Enfermedades Musculares/terapia , Mioblastos/trasplante , Trasplante de Tejidos/métodos , Factor de Necrosis Tumoral alfa/metabolismo , Animales , Diferenciación Celular/efectos de los fármacos , Células Cultivadas , Quimiotaxis/efectos de los fármacos , Citocinas/inmunología , Citocinas/metabolismo , Relación Dosis-Respuesta a Droga , Inmunosupresores/farmacología , Antígeno-1 Asociado a Función de Linfocito/efectos de los fármacos , Antígeno-1 Asociado a Función de Linfocito/metabolismo , Antígeno de Macrófago-1/efectos de los fármacos , Antígeno de Macrófago-1/metabolismo , Metaloproteinasas de la Matriz/efectos de los fármacos , Metaloproteinasas de la Matriz/metabolismo , Ratones , Ratones Transgénicos , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/lesiones , Mioblastos/efectos de los fármacos , Mioblastos/metabolismo , Resultado del Tratamiento , Factor de Necrosis Tumoral alfa/farmacología
18.
Ann Thorac Surg ; 57(6): 1660-1, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8010825

RESUMEN

A 33-year-old woman presented with progressive dysphagia 3 years after implantation of an Angelchik prosthesis for esophageal reflux disease. Routine esophageal testing was normal. Esophagogastroduodenoscopy and computed tomography suggested migration of the prosthesis. Because of the persistent and progressive dysphagia, the device was removed. All symptoms of dysphagia or reflux have since resolved. Routine esophageal testing may not be helpful in the evaluation of dysphagia associated with the Angelchik prosthesis.


Asunto(s)
Trastornos de Deglución/etiología , Reflujo Gastroesofágico/cirugía , Prótesis e Implantes/efectos adversos , Adulto , Endoscopía del Sistema Digestivo , Femenino , Migración de Cuerpo Extraño/complicaciones , Reflujo Gastroesofágico/fisiopatología , Motilidad Gastrointestinal , Humanos , Presión
19.
Eur J Pharmacol ; 330(2-3): 165-76, 1997 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-9253950

RESUMEN

Renal hemodynamics were studied using an electromagnetic perivascular flow sensor in anesthetized rats injected i.v. with vehicle, 5 or 10 mg/kg body weight (b.w.) sulindac. No hemodynamic changes occurred with vehicle (n = 6), but mean arterial pressure was significantly decreased (by 15 mmHg) with sulindac (n = 12). In the 5 mg/kg b.w. sulindac group (n = 7), renal blood flow progressively and significantly increased from 7.88 +/- 0.36 to 8.98 +/- 0.58 ml/min, except during concomitant intrarenal infusion of 3 mg/kg b.w. per h proadifen (n = 7). The pressure limits for efficient and no renal blood flow autoregulation remained unchanged (approx. 100 and 80 mmHg, respectively). In the 10 mg/kg b.w. sulindac group (n = 5), renal blood flow did not change but autoregulatory pressure limits were lowered by 10 mmHg 2 h after treatment (P < 0.025). Also, Na+ retention was marked. Prostanoid excretion in urine was significantly reduced with either dose but basal plasma renin activity was not (about 8 ng/ml per h; n = 15). When plasma renin activity was enhanced after a reduction in renal perfusion pressure (n = 21), it was decreased from 11.5 +/- 1.2 to 7.4 +/- 0.2 ng/ml per h only by 10 mg/kg b.w. sulindac (P < 0.05; n = 6). In conclusion, differential effects of sulindac on renal hemodynamics, Na+ excretion and plasma renin activity were demonstrated. Renal hemodynamic changes could be related in part to the cytochrome P-450 arachidonic acid pathway.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Inhibidores de la Ciclooxigenasa/farmacología , Riñón/efectos de los fármacos , Riñón/fisiología , Circulación Renal/efectos de los fármacos , Sulindac/farmacología , Animales , Ácido Araquidónico/metabolismo , Sistema Enzimático del Citocromo P-450/metabolismo , Relación Dosis-Respuesta a Droga , Interacciones Farmacológicas , Tasa de Filtración Glomerular/efectos de los fármacos , Riñón/irrigación sanguínea , Masculino , Potasio/sangre , Potasio/orina , Proadifeno/farmacología , Prostaglandinas/biosíntesis , Ratas , Ratas Wistar , Renina/sangre , Sodio/sangre , Sodio/orina , Agua/metabolismo
20.
Am J Surg ; 171(5): 490-4, 1996 May.
Artículo en Inglés | MEDLINE | ID: mdl-8651392

RESUMEN

BACKGROUND: Objectives of partial medium aperture mesocaval shunts (MCS) include reduction of portal hypertension to prevent recurrent variceal hemorrhage, preservation of portal flow through liver while maintaining an intact porta hepatis to facilitate a future liver transplant (OLTx). PATIENTS AND METHODS: Fifteen patients were retrospectively analyzed to review the indications for the procedure, its short- and long-term complications as well as patency and functional status of the shunt. They were followed for a period of 21 months. RESULTS: The perioperative and long-term mortality rate was 0%. Rebleeding rate perioperatively and in follow-up was 0%. Early shunt nonfunction was 13% and post-shunt encephalopathy (PSE) was 20%. The encephalopathy was grade I to II and controlled medically. Abdominal ultrasound and Doppler confirmed 13 patent shunts (2 patients did not agree to ultrasound) with preserved hepatopetal flow in 10. CONCLUSIONS: Medium aperture MCS utilizing ringed polytetrafluoroethylene (PTFE) grafts safely and reliably prevent recurrent variceal hemorrhage. Encephalopathy is infrequent and mild. This technique preserves the portal venous anatomy making a future OLTx technically easier.


Asunto(s)
Várices Esofágicas y Gástricas/cirugía , Hemorragia Gastrointestinal/cirugía , Hipertensión Portal/cirugía , Derivación Portosistémica Quirúrgica/métodos , Adulto , Anciano , Prótesis Vascular , Várices Esofágicas y Gástricas/complicaciones , Femenino , Hemorragia Gastrointestinal/complicaciones , Humanos , Hipertensión Portal/etiología , Masculino , Persona de Mediana Edad , Politetrafluoroetileno , Recurrencia , Resultado del Tratamiento
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