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1.
Ann Oncol ; 29(1): 133-138, 2018 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-29045659

RESUMEN

Background: Metastatic colorectal cancer frequently occurs in elderly patients. Bevacizumab in combination with front line chemotherapy (CT) is a standard treatment but some concern raised about tolerance of bevacizumab for these patients. The purpose of PRODIGE 20 was to evaluate tolerance and efficacy of bevacizumab according to specific end points in this population. Patients and methods: Patients aged 75 years and over were randomly assigned to bevacizumab + CT (BEV) versus CT. LV5FU2, FOLFOX and FOLFIRI regimen were prescribed according to investigator's choice. The composite co-primary end point, assessed 4 months after randomization, was based on efficacy (tumor control and absence of decrease of the Spitzer QoL index) and safety (absence of severe cardiovascular toxicities and unexpected hospitalization). For each arm, the treatment will be consider as inefficient if 20% or less of the patients met the efficacy criteria and not safe if 40% or less met the safety criteria. Results: About 102 patients were randomized (51 BEV and 51 CT), median age was 80 years (range 75-91). Primary end point was met for efficacy in 50% and 58% and for safety in 61% and 71% of patients in BEV and CT, respectively. Median progression-free survival was 9.7 months in BEV and 7.8 months in CT. Median overall survival was 21.7 months in BEV and 19.8 months in CT. The 36-month overall survival rate was 27% in BEV and 10.1% in CT. Severe toxicities grade 3/4 were mainly non-hematologic toxicities (80.4% in BEV, 63.3% in CT). Conclusion: Bevacizumab combined with CT was safe and efficient. Both arms met the primary safety and efficacy criteria.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Colorrectales/tratamiento farmacológico , Factores de Edad , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Bevacizumab/administración & dosificación , Camptotecina/administración & dosificación , Camptotecina/análogos & derivados , Neoplasias Colorrectales/patología , Femenino , Fluorouracilo/administración & dosificación , Humanos , Leucovorina/administración & dosificación , Masculino , Metástasis de la Neoplasia , Compuestos Organoplatinos/administración & dosificación , Tasa de Supervivencia
2.
Am J Transplant ; 17(2): 451-461, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27456745

RESUMEN

Clinical islet transplantation achieves insulin independence in selected patients, yet current methods for extracting islets from their surrounding pancreatic matrix are suboptimal. The islet basement membrane (BM) influences islet function and survival and is a critical marker of islet integrity following rodent islet isolation. No studies have investigated the impact of islet isolation on BM integrity in human islets, which have a unique duplex structure. To address this, samples were taken from 27 clinical human islet isolations (donor age 41-59, BMI 26-38, cold ischemic time < 10 h). Collagen IV, pan-laminin, perlecan and laminin-α5 in the islet BM were significantly digested by enzyme treatment. In isolated islets, laminin-α5 (found in both layers of the duplex BM) and perlecan were lost entirely, with no restoration evident during culture. Collagen IV and pan-laminin were present in the disorganized BM of isolated islets, yet a significant reduction in pan-laminin was seen during the initial 24 h culture period. Islet cytotoxicity increased during culture. Therefore, the human islet BM is substantially disrupted during the islet isolation procedure. Islet function and survival may be compromised as a consequence of an incomplete islet BM, which has implications for islet survival and transplanted graft longevity.


Asunto(s)
Membrana Basal/metabolismo , Separación Celular , Colágeno Tipo IV/metabolismo , Proteoglicanos de Heparán Sulfato/metabolismo , Islotes Pancreáticos/metabolismo , Laminina/metabolismo , Proteínas de la Membrana/metabolismo , Adulto , Células Cultivadas , Femenino , Humanos , Islotes Pancreáticos/citología , Trasplante de Islotes Pancreáticos , Masculino , Persona de Mediana Edad
3.
Ann Oncol ; 27(1): 121-7, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26487578

RESUMEN

BACKGROUND: Metastatic colorectal cancer (mCRC) frequently occurs in elderly patients. However, data from a geriatric tailored randomized trial about tolerance to and the efficacy of doublet chemotherapy (CT) with irinotecan in the elderly are lacking. The benefit of first-line CT intensification remains an issue in elderly patients. PATIENTS AND METHODS: Elderly patients (75+) with previously untreated mCRC were randomly assigned in a 2 × 2 factorial design (four arms) to receive 5-FU (5-fluorouracil)-based CT, either alone (FU: LV5FU2 or simplified LV5FU2) or in combination with irinotecan [IRI: LV5FU2-irinotecan or simplified LV5FU2-irinotecan (FOLFIRI)]. The CLASSIC arm was defined as LV5FU2 or LV5FU2-irinotecan and the SIMPLIFIED arm as simplified LV5FU2 or FOLFIRI. The primary end point was progression-free survival (PFS). Secondary end points were overall survival (OS), safety and objective response rate (ORR). RESULTS: From June 2003 to May 2010, 71 patients were randomly assigned to LV5FU2, 71 to simplified LV5FU2, 70 to LV5FU2-irinotecan and 70 to FOLFIRI. The median age was 80 years (range 75-92 years). No significant difference was observed for the median PFS: FU 5.2 months versus IRI 7.3 months, hazard ratio (HR) = 0.84 (0.66-1.07), P = 0.15 and CLASSIC 6.5 months versus SIMPLIFIED 6.0 months, HR = 0.85 (0.67-1.09), P = 0.19. The ORR was superior in IRI (P = 0.0003): FU 21.1% versus IRI 41.7% and in CLASSIC (P = 0.04): CLASSIC 37.1% versus SIMPLIFIED 25.6%. Median OS was 14.2 months in FU versus 13.3 months in IRI, HR = 0.96 (0.75-1.24) and 15.2 months in CLASSIC versus 11.4 months in SIMPLIFIED, HR = 0.71 (0.55-0.92). More patients presented grade 3-4 toxicities in IRI (52.2% versus 76.3%). CONCLUSION: In this elderly population, adding irinotecan to an infusional 5-FU-based CT did not significantly increase either PFS or OS. Classic LV5FU2 was associated with an improved OS compared with simplified LV5FU2. CLINICALTRIALSGOV: NCT00303771.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Colorrectales/tratamiento farmacológico , Adenocarcinoma/mortalidad , Adenocarcinoma/secundario , Anciano , Anciano de 80 o más Años , Camptotecina/administración & dosificación , Camptotecina/análogos & derivados , Neoplasias Colorrectales/mortalidad , Neoplasias Colorrectales/patología , Femenino , Fluorouracilo/administración & dosificación , Humanos , Irinotecán , Leucovorina/administración & dosificación , Masculino , Análisis Multivariante , Modelos de Riesgos Proporcionales , Resultado del Tratamiento
4.
Br J Surg ; 103(1): 117-25, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26511668

RESUMEN

BACKGROUND: Patterns of disease recurrence in patients with oesophageal cancer following treatment with neoadjuvant chemoradiotherapy and surgery (nCRTS) or surgery alone are poorly reported. An understanding of patterns of disease recurrence is important for subsequent treatment planning. METHODS: An analysis was undertaken of patterns of disease recurrence from a phase III multicentre randomized trial (FFCD9901) comparing nCRTS with surgery alone in patients with stage I and II oesophageal cancer. RESULTS: Some 170 patients undergoing surgical resection were included in the study. R0 resection rates were similar in the two groups: 94 per cent following nCRTS versus 92 per cent after surgery alone (P = 0·749). After a median follow-up of 94·2 months, recurrent disease was found in 39·4 per cent of the overall cohort (31 per cent after nCRTS versus 47 per cent following surgery alone; P = 0·030). Locoregional recurrence was diagnosed in 41 patients (17 versus 30 per cent respectively; P = 0·047) and distant metastatic recurrence in 47 (23 versus 31 per cent respectively; P = 0·244). Metastatic recurrence was more frequent in patients with adenocarcinoma than in those with squamous cell cancer (40 versus 23·1 per cent respectively; P = 0·032). ypT0 N0 category was associated with prolonged time to mixed locoregional and metastatic recurrence (P = 0·009), and time to locoregional (P = 0·044) and metastatic (P = 0·055) recurrence. In multivariable analysis, node-positive disease predicted both locoregional (P = 0·001) and metastatic (P < 0·001) recurrence. CONCLUSION: Locoregional disease control following nCRTS indicated a local field effect not related solely to completeness of resection. pN+ disease was strongly predictive of time to locoregional and metastatic disease recurrence.


Asunto(s)
Adenocarcinoma/terapia , Carcinoma de Células Escamosas/terapia , Quimioradioterapia Adyuvante , Neoplasias Esofágicas/terapia , Esofagectomía , Terapia Neoadyuvante , Recurrencia Local de Neoplasia/epidemiología , Adenocarcinoma/patología , Adulto , Anciano , Carcinoma de Células Escamosas/patología , Neoplasias Esofágicas/patología , Femenino , Estudios de Seguimiento , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Recurrencia Local de Neoplasia/patología , Modelos de Riesgos Proporcionales , Resultado del Tratamiento
6.
Gastroenterol Clin Biol ; 34(4-5): 314-8, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20207091

RESUMEN

Sorafenib has recently been approved as the gold standard therapy for advanced BCLC-C hepatocellular carcinomas. Although significant improvement of survival rates was shown, objective tumor response rates remained low following RECIST criteria in phases 2 and 3 studies. We report the rare case of a patient with a large hepatocellular carcinoma tumor invading suprahepatic veins in which sorafenib led to a very significant regression by about 90% of the tumor bulk, thus allowing at sterilizing the residual tumor tissue by subsequent combination of transarterial intrahepatic chemoembolization and high dose radiotherapy.


Asunto(s)
Antineoplásicos/uso terapéutico , Bencenosulfonatos/uso terapéutico , Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/terapia , Piridinas/uso terapéutico , Carcinoma Hepatocelular/patología , Quimioembolización Terapéutica , Terapia Combinada , Humanos , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Niacinamida/análogos & derivados , Compuestos de Fenilurea , Dosificación Radioterapéutica , Radioterapia Conformacional , Sorafenib , alfa-Fetoproteínas/análisis
7.
Transplant Proc ; 40(2): 473-6, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18374106

RESUMEN

During pancreatic islet transplantation, delayed and insufficient revascularization can deprive islets of oxygen and nutrients, resulting in cell death and early graft failure. Deferoxamine (DFO), an iron chelator, increases vascular endothelial growth factor (VEGF) expression in cells. The aim of this work was to study the effect of DFO on beta-cell and pancreatic islet viability as well as VEGF expression. beta-cell lines from rat insulinoma (Rin m5f) and primary cultures of pancreatic islets from Wistar rats were incubated with DFO (10, 100, and 1000 micromol/L). The viability was evaluated using fluorescein diacetate/propidium iodide for dying pancreatic islets and using cell titers for Rin m5f. Expression of VEGF messenger RNA (mRNA) was quantified using reverse transcriptase polymerase chain reaction (RT-PCR). Finally, VEGF secretion was determined using enzyme-linked immunosorbent assays at 1 to 3 days after treatment. The addition of 10 micromol/L of DFO preserved Rin m5F viability at 24 hours after treatment (10 micromol/L; 101.33% +/- 5.66%; n = 7). However, 100 and 1000 micromol/L of DFO induced cell death (68.92% +/- 5.83% and 65.89% +/- 5.83%, respectively; n = 4). In the same way, viability of pancreatic islets in the presence of DFO was preserved. RT-PCR analysis showed stimulation of VEGF mRNA in the presence of 10 micromol/L of DFO in islets at 3 days after culture. Finally, 10 micromol/L of DFO stimulated secretion of VEGF 7.95 +/- 0.84 versus 1.80 +/- 1.10 pg/microg total protein with 10 micromol/L of DFO in rat islets at 3 days after culture, n = 3; P < .001). The use of DFO to stimulate VEGF expression and increase islet vascularization may be a realistic approach to improve islet viability during transplantation.


Asunto(s)
Deferoxamina/uso terapéutico , Células Secretoras de Insulina/fisiología , Trasplante de Islotes Pancreáticos/fisiología , Neovascularización Fisiológica/efectos de los fármacos , Factor A de Crecimiento Endotelial Vascular/genética , Animales , Supervivencia Celular/efectos de los fármacos , Células Secretoras de Insulina/citología , Células Secretoras de Insulina/efectos de los fármacos , Islotes Pancreáticos/irrigación sanguínea , Neovascularización Fisiológica/fisiología , Ratas , Ratas Wistar
8.
Transplant Proc ; 40(2): 372-4, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18374072

RESUMEN

Pancreatic islet transplantations to treat type 1 diabetes often fail to function because of hypoxia. Perfluorocarbons (PFCs) exhibit a high oxygen solubility coefficient and maintain high oxygen partial pressure for extended times. They also serve as oxygen "reservoirs" for harvested organs in pancreas organ transplantation. Previous studies have shown the PFCs display antiadhesive effects on beta cells. The aim of this study was to evaluate the effects of PFC on islet viability and functionality and on extracellular matrix (ECM) disruption of islets via inhibition of adhesion. Primary cultures of rat islets were incubated for 24 hours in the presence or absence of 3.5% (weight/volume) PFCs in culture media. We studied viability (FDA/PI), stimulation index linked to insulin secretion (ELISA), and expression of insulin and laminin messenger RNAs (mRNAs). Immunostaining was performed on insulin and laminin. Islet viability was similar in the presence or absence of PFCs (about 80%). Stimulation index showed preservation of islet functionality in the presence of PFC (4.9 +/- 0.7) as compared with controls (2.8 +/- 0.5). Moreover, laminin mRNA expression was lower compared with controls (55% of PFC incubated vs control islets). Immunohistochemistry studies showed preservation of ECM inside the islets in the presence of PFCs versus controls at 24 hours after islet isolation. In conclusion, PFCs preserved islet viability and functionality and prevented ECM disruption. PFCs may represent a new tool for islet preservation in vitro.


Asunto(s)
Fluorocarburos/farmacología , Islotes Pancreáticos/citología , Conservación de Tejido/métodos , Actinas/genética , Animales , Inmunohistoquímica , Insulina/genética , Islotes Pancreáticos/efectos de los fármacos , Islotes Pancreáticos/fisiología , Laminina/genética , Tamaño de los Órganos , Páncreas/anatomía & histología , ARN Mensajero/genética , Ratas , Ratas Wistar , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
9.
Gastroenterol Clin Biol ; 32(11): 953-9, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18774666

RESUMEN

OBJECTIVE: To search for clinical risk factors and symptoms of elytrocele in female patients without hysterectomy. PATIENTS AND METHODS: Of 1060 women who underwent defecography, radiographic evidence of elytrocele was observed in 303. History-taking was standardized, and included obstetric, surgical and medical history as well as clinical symptoms and their duration. Group A comprised 192 women with hysterectomy while group B included 111 women with no history of hysterectomy; these two groups were compared. Group B was also compared with patients who had neither elytrocele nor hysterectomy (group C; n=516). RESULTS: Women in group B (no hysterectomy) were younger than those in group A (with hysterectomy) (57.9 years versus 62.8 years; p<0.05). Patients in group B had fewer obstetric (87.4% versus 97.9%; p=0.01) and abdominal (64.9 versus 82.3%; p=0.01) surgical events than those in group A, but more urinary tract surgery (18.9% versus 10.9%) and higher infant birth weights than patients in control group C. Six women (2%) had no surgical or obstetric history: mean age 42.7 years (20.6-74 years). Group B used protection against urinary soiling less often (17.3% versus 29.07%; p=0.017), but had more fecal soiling (23.4% versus 13.6%; p=0.033). Defecography showed that women in group B had more external rectal prolapse (17.7% versus 4.9%; p=0.003) and cystocele (48.6% versus 34.9%; p=0.019) than those in group A. CONCLUSIONS: This study was unable to identify risk factors of elytrocele in patients without hysterectomy except for a history of urinary tract surgery and higher infant birth weights. In some women, the elytrocele may be the result of significant rectal prolapse as part of a major pelvic floor disorder, predominantly in the posterior pelvis. Constitutional or congenital causes could also be involved as several young women free of any surgical or obstetric history nevertheless presented with an elytrocele.


Asunto(s)
Defecografía , Fondo de Saco Recto-Uterino , Hernia/diagnóstico por imagen , Histerectomía , Enfermedades Peritoneales/diagnóstico por imagen , Femenino , Hernia/etiología , Humanos , Persona de Mediana Edad , Enfermedades Peritoneales/etiología , Factores de Riesgo
10.
Br J Pharmacol ; 173(24): 3443-3453, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27515367

RESUMEN

BACKGROUND AND PURPOSE: Liraglutide improves the metabolic control of diabetic animals after islet transplantation. However, the mechanisms underlying this effect remain unknown. The objective of this study was to evaluate the anti-inflammatory and anti-oxidative properties of liraglutide on rat pancreatic islets in vitro and in vivo. EXPERIMENTAL APPROACH: In vitro, rat islets were incubated with 10 µmol·L-1 liraglutide for 12 and 24 h. Islet viability functionality was assessed. The anti-inflammatory properties of liraglutide were evaluated by measuring CCL2, IL-6 and IL-10 secretion and macrophage chemotaxis. The anti-oxidative effect of liraglutide was evaluated by measuring intracellular ROS and the total anti-oxidative capacity. In vivo, 1000 islets were cultured for 24 h with or without liraglutide and then transplanted into the liver of streptozotocin-induced diabetic Lewis rats with or without injections of liraglutide. Effects of liraglutide on metabolic control were evaluated for 1 month. KEY RESULTS: Islet viability and function were preserved and enhanced with liraglutide treatment. Liraglutide decreased CCL2 and IL-6 secretion and macrophage activation after 12 h of culture, while IL-10 secretion was unchanged. However, intracellular levels of ROS were increased with liraglutide treatment at 12 h. This result was correlated with an increase of anti-oxidative capacity. In vivo, liraglutide decreased macrophage infiltration and reduced fasting blood glucose in transplanted rats. CONCLUSIONS AND IMPLICATIONS: The beneficial effects of liraglutide on pancreatic islets appear to be linked to its anti-inflammatory and anti-oxidative properties. These findings indicated that analogues of glucagon-like peptide-1 could be used to improve graft survival.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Inflamación/tratamiento farmacológico , Trasplante de Islotes Pancreáticos , Islotes Pancreáticos/efectos de los fármacos , Liraglutida/farmacología , Animales , Antiinflamatorios no Esteroideos/administración & dosificación , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Relación Dosis-Respuesta a Droga , Islotes Pancreáticos/citología , Islotes Pancreáticos/metabolismo , Liraglutida/administración & dosificación , Masculino , Estrés Oxidativo/efectos de los fármacos , Ratas , Ratas Endogámicas Lew , Ratas Wistar , Especies Reactivas de Oxígeno/metabolismo , Relación Estructura-Actividad
11.
J Diabetes Res ; 2016: 3615286, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26824040

RESUMEN

In bioartificial pancreases (BP), the number of islets needed to restore normoglycaemia in the diabetic patient is critical. However, the confinement of a high quantity of islets in a limited space may impact islet survival, particularly in regard to the low oxygen partial pressure (PO2) in such environments. The aim of the present study was to evaluate the impact of islet number in a confined space under hypoxia on cell survival. Rat islets were seeded at three different concentrations (150, 300, and 600 Islet Equivalents (IEQ)/cm(2)) and cultured in normal atmospheric pressure (160 mmHg) as well as hypoxic conditions (15 mmHg) for 24 hours. Cell viability, function, hypoxia-induced changes in gene expression, and cytokine secretion were then assessed. Notably, hypoxia appeared to induce a decrease in viability and increasing islet density exacerbated the observed increase in cellular apoptosis as well as the loss of function. These changes were also associated with an increase in inflammatory gene transcription. Taken together, these data indicate that when a high number of islets are confined to a small space under hypoxia, cell viability and function are significantly impacted. Thus, in order to improve islet survival in this environment during transplantation, oxygenation is of critical importance.


Asunto(s)
Islotes Pancreáticos/metabolismo , Oxígeno/metabolismo , Animales , Apoptosis , Presión Atmosférica , Hipoxia de la Célula , Supervivencia Celular , Citocinas/genética , Citocinas/metabolismo , Regulación de la Expresión Génica , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Mediadores de Inflamación/metabolismo , Islotes Pancreáticos/patología , Masculino , Ratas Wistar , Factores de Tiempo , Técnicas de Cultivo de Tejidos
12.
J Diabetes Res ; 2016: 8310516, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27504460

RESUMEN

Exogenous insulin is the only treatment available for type 1 diabetic patients and is mostly administered by subcutaneous (SC) injection in a basal and bolus scheme using insulin pens (injection) or pumps (preimplanted SC catheter). Some divergence exists between these two modes of administration, since pumps provide better glycaemic control compared to injections in humans. The aim of this study was to compare the impacts of two modes of insulin administration (single injections of long-acting insulin or pump delivery of rapid-acting insulin) at the same dosage (4 IU/200 g/day) on rat metabolism and tissues. The rat weight and blood glucose levels were measured periodically after treatment. Immunostaining for signs of oxidative stress and for macrophages was performed on the liver and omental tissues. The continuous insulin delivery by pumps restored normoglycaemia, which induced the reduction of both reactive oxygen species and macrophage infiltration into the liver and omentum. Injections controlled the glucose levels for only a short period of time and therefore tissue stress and inflammation were elevated. In conclusion, the insulin administration mode has a crucial impact on rat metabolic parameters, which has to be taken into account when studies are designed.


Asunto(s)
Glucemia/efectos de los fármacos , Diabetes Mellitus Experimental/tratamiento farmacológico , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Hipoglucemiantes/administración & dosificación , Insulina Glargina/administración & dosificación , Insulina/administración & dosificación , Hígado/efectos de los fármacos , Macrófagos/efectos de los fármacos , Epiplón/efectos de los fármacos , Animales , Glucemia/metabolismo , Peso Corporal , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Hipoglucemiantes/farmacología , Insulina/farmacología , Insulina Glargina/farmacología , Sistemas de Infusión de Insulina , Hígado/citología , Macrófagos/citología , Masculino , Epiplón/citología , Ratas , Ratas Endogámicas Lew , Especies Reactivas de Oxígeno/metabolismo
13.
Biomaterials ; 52: 180-8, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25818424

RESUMEN

Disruption of the pancreatic islet environment combined with the decrease in oxygen supply that occurs during isolation leads to poor islet survival. The aim of this study was to validate the benefit of using a plasma-based scaffold supplemented with perfluorodecalin to improve islet transplantation outcome. Rat islets were cultured in three conditions: i) control group, ii) plasma based-matrix (P-matrix), and iii) P-matrix supplemented with emulsified perfluorodecalin. After 24 h culture, matrix/cell contacts (Integrinß1, p-FAK/FAK, p-Akt/Akt), survival (caspase 3, TUNEL, FDA/PI), function, and HIF-1α translocation were assessed. Afterwards, P-matrices were dissolved and the islets were intraportally transplanted. Graft function was monitored for 31 days with glycaemia and C-peptide follow up. Inflammation was assessed by histology (macrophage and granulocyte staining) and thrombin/anti-thrombin complex measurement. Islet survival correlated with an increase in integrin, FAK, and Akt activation in P-matrices and function was maintained. Perfluorodecalin supplementation decreased translocation of HIF-1α in the nucleus and post-transplantation islet structure was better preserved in P-matrices, but a quicker activation of IBMIR resulted in early loss of graft function. "Oxygenating" P-matrices provided a real benefit to islet survival and resistance in vivo. However, intraportal transplantation is not suitable for this kind of culture due to IBMIR; thus, alternative sites must be explored.


Asunto(s)
Técnicas de Cultivo de Célula/métodos , Trasplante de Islotes Pancreáticos/métodos , Islotes Pancreáticos/citología , Oxígeno/metabolismo , Animales , Hipoxia de la Célula , Supervivencia Celular , Células Cultivadas , Fluorocarburos/metabolismo , Supervivencia de Injerto , Islotes Pancreáticos/metabolismo , Islotes Pancreáticos/ultraestructura , Masculino , Ratas , Ratas Endogámicas Lew , Ratas Wistar
14.
Sci Total Environ ; 499: 327-35, 2014 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-25201820

RESUMEN

Knowledge of wetland bacterial communities in the context of pesticide contamination and hydrological regime is scarce. We investigated the bacterial composition in constructed wetlands receiving Mercantor Gold(®) contaminated water (960 g L(-1) of the herbicide S-metolachlor, >80% of the S-enantiomer) operated under continuous-flow or batch modes to evaluate the impact of the hydraulic regime. In the continuous-flow wetland, S-metolachlor mass removal was >40%, whereas in the batch wetland, almost complete removal of S-metolachlor (93-97%) was observed. Detection of ethanesulfonic and oxanilic acid degradation products further indicated S-metolachlor biodegradation in the two wetlands. The dominant bacterial populations were characterised by terminal restriction fragment length polymorphism (T-RFLP) and 454 pyrosequencing. The bacterial profiles evolved during the first 35 days of the experiment, starting from a composition similar to that of inlet water, with the use of nitrate and to a lesser extent sulphate and manganese as terminal electron acceptors for microbial metabolism. Proteobacteria were the most abundant phylum, with Beta-, Alpha- and Gammaproteobacteria representing 26%, 19% and 17% respectively of total bacterial abundance. Bacterial composition in wetland water changed gradually over time in continuous-flow wetland and more abruptly in the batch wetland. Differences in overall bacterial water structure in the two systems were modest but significant (p=0.008), and S-metolachlor, nitrate, and total inorganic carbon concentrations correlated with changes in the bacterial profiles. Together, the results highlight that bacterial composition profiles and their dynamics may be used as bioindicators of herbicide exposure and hydraulic disturbances in wetland systems.


Asunto(s)
Acetamidas/análisis , Bacterias/crecimiento & desarrollo , Herbicidas/análisis , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua/análisis , Humedales , Acetamidas/metabolismo , Bacterias/clasificación , Biodegradación Ambiental , Herbicidas/metabolismo , Contaminantes Químicos del Agua/metabolismo
15.
Chemosphere ; 99: 89-95, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24256720

RESUMEN

Compound-specific isotope analysis (CSIA) is a promising tool to study the environmental fate of a wide range of contaminants including pesticides. In this study, a novel CSIA method was developed to analyse the stable carbon isotope signatures of widely used chloroacetanilide herbicides. The developed method was applied in combination with herbicide concentration and hydrochemical analyses to investigate in situ biodegradation of metolachlor, acetochlor and alachlor during their transport in lab-scale wetlands. Two distinct redox zones were identified in the wetlands. Oxic conditions prevailed close to the inlet of the four wetlands (oxygen concentration of 212±24µM), and anoxic conditions (oxygen concentrations of 28±41µM) prevailed towards the outlet, where dissipation of herbicides mainly occurred. Removal of acetochlor and alachlor from inlet to outlet of wetlands was 56% and 51%, whereas metolachlor was more persistent (23% of load dissipation). CSIA of chloroacetanilides at the inlet and outlet of the wetlands revealed carbon isotope fractionation of alachlor (εbulk=-2.0±0.3‰) and acetochlor (εbulk=-3.4±0.5‰), indicating that biodegradation contributes to the dissipation of both herbicides. This study is a first step towards the application of CSIA to evaluate the transport and degradation of chloroacetanilide herbicides in the environment.


Asunto(s)
Acetamidas/química , Herbicidas/química , Modelos Químicos , Humedales , Acetamidas/análisis , Biodegradación Ambiental , Fraccionamiento Químico , Herbicidas/análisis , Toluidinas/análisis , Toluidinas/química
16.
Cell Transplant ; 21(4): 657-69, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-21944582

RESUMEN

As oxygen carriers, perfluorocarbon emulsions might be useful to decrease hypoxia of pancreatic islets before transplantation. However, their hydrophobicity prevents their homogenisation in culture medium. To increase the surface of contact between islets and Perfluorooctyl bromide (PFOB), and consequently oxygen delivery, we tested effect of a PFOB emulsion in culture medium on ß-cell lines and rat pancreatic islets. RINm5F ß-cell line or pancreatic rat islets were incubated for 3 days in the presence of PFOB emulsion in media (3.5% w/v). Preoxygenation of the medium was performed before culture. Cell viability was assessed by apoptotic markers (Bax and Bcl-2) and by staining (fluoresceine diacetate and propidium iodide). ß-Cell functionality was determined by insulin release during a glucose stimulation test and. Hypoxia markers, HIF-1α and VEGF, were studied at days 1 and 3 using RT-PCR, Western blotting, and ELISA. PFOB emulsions preserved viability and functionality of RINm5F cells with a decrease of HIF-1α and VEGF expression. Islets viability was preserved during 3 days of culture. Secretion of VEGF was higher in untreated control (0.09 ± 0.041 µg VEGF/mg total protein) than in PFOB emulsion incubated islets (0.02 ± 0.19 µg VEGF/mg total protein, n = 4, p < 0.05) at day 1. At day 3, VEGF secretion was increased as compared to day 1 in control (0.23 ± 0.04 µg VEGF/mg total protein) but it was imbalance by the presence of PFOB emulsion (0.09 ± 0.03 µg VEGF/mg total protein, n = 5, p < 0.05). While insulin secretion was maintained in response to a glucose stimulation test until day 3 when islets were incubated in the presence of PFOB emulsion preoxygenated (0.81 ± 0.16 at day 1 vs. 0.75 ± 0.24 at day 3), the ability to secrete insulin in the presence of high glucose concentration was lost in islets controls (0.51 ± 0.18 at day 1 vs. 0.21 ± 0.13 at day 3). Atmospheric oxygen delivery by PFOB emulsion might be sufficient to decrease islets hypoxia. However, to improve islets functionality, overoxygenation is needed. Finally, maintenance of islet viability and functionality for several days after isolation could improve the outcome of islets transplantation.


Asunto(s)
Hipoxia de la Célula/efectos de los fármacos , Fluorocarburos/farmacología , Células Secretoras de Insulina/efectos de los fármacos , Islotes Pancreáticos/efectos de los fármacos , Animales , Supervivencia Celular/efectos de los fármacos , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Inmunohistoquímica , Células Secretoras de Insulina/citología , Células Secretoras de Insulina/metabolismo , Islotes Pancreáticos/citología , Islotes Pancreáticos/metabolismo , Ratas , Factor A de Crecimiento Endotelial Vascular/metabolismo
17.
Cancer Radiother ; 15(1): 3-6, 2011 Feb.
Artículo en Francés | MEDLINE | ID: mdl-21239205

RESUMEN

Hepatocellular carcinoma (HCC) is the main type of primary liver cancers and the third most common cause of cancer mortality worldwide. In France, rising number between 5000 and 6000 cases are diagnosed each year. The major risk factor for hepatocellular carcinoma is chronic hepatitis: viral hepatitis B, viral hepatitis C, consumption of alcohol, hemochromatosis. Hepatocellular carcinoma is closely associated to liver cirrhosis, which is a true precancerous state. Because hepatocarcinogenesis is a long and heterogeneous process, there is still much to understand. Many genetic and epigenetic alterations are described leading to changes in cellular signalling cascades involved in regulation of growth, differentiation, apoptosis, motility. Hepatitis viruses play a direct oncogenic role through the interaction between viral and cellular proteins, which control cell homeostasis, or by the integration of hepatitis B virus genome into the host genome. Furthermore, hepatitis viruses play an indirect oncogenic role by causing chronic inflammation and hepatocyte regeneration related to viral hepatopathy. In expectation of a better understanding of hepatocarcinogenesis and new treatments, prevention from risk factors and ultrasonographic screening of patients with cirrhosis should increase prognosis.


Asunto(s)
Carcinoma Hepatocelular/epidemiología , Carcinoma Hepatocelular/etiología , Neoplasias Hepáticas/epidemiología , Neoplasias Hepáticas/etiología , Hepatitis/complicaciones , Humanos , Cirrosis Hepática/complicaciones , Virus Oncogénicos
18.
Cell Transplant ; 20(9): 1333-42, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21294962

RESUMEN

Delayed and insufficient revascularization during islet transplantation deprives islets of oxygen and nutrients, resulting in graft failure. Vascular endothelial growth factor (VEGF) could play a critical role in islet revascularization. We aimed to develop pharmacological strategies for VEGF overexpression in pancreatic islets using the iron chelator deferoxamine (DFO), thus avoiding obstacles or safety risks associated with gene therapy. Rat pancreatic islets were infected in vivo using an adenovirus (ADE) encoding human VEGF gene (4.10(8) pfu/pancreas) or were incubated in the presence of DFO (10 µmol/L). In vitro viability, functionality, and the secretion of VEGF were evaluated in islets 1 and 3 days after treatment. Infected islets or islets incubated with DFO were transplanted into the liver of syngenic diabetic rats and the graft efficiency was estimated in vivo by measuring body weight, glycemia, C-peptide secretion, and animal survival over a period of 2 months. DFO induced transient VEGF overexpression over 3 days, whereas infection with ADE resulted in prolonged VEGF overexpression lasting 14 days; however, this was toxic and decreased islet viability and functionality. The in vivo study showed a decrease in rat deaths after the transplantation of islets treated with DFO or ADE compared with the sham and control group. ADE treatment improved body weight and C-peptide levels. Gene therapy and DFO improved metabolic control in diabetic rats after transplantation, but this effect was limited in the presence of DFO. The pharmacological approach is an interesting strategy for improving graft efficiency during transplantation, but this approach needs to be improved with drugs that are more specific.


Asunto(s)
Deferoxamina/farmacología , Trasplante de Islotes Pancreáticos , Supervivencia Tisular/efectos de los fármacos , Factor A de Crecimiento Endotelial Vascular/metabolismo , Infecciones por Adenoviridae/patología , Animales , Peso Corporal/efectos de los fármacos , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Insulina/metabolismo , Secreción de Insulina , Islotes Pancreáticos/metabolismo , Islotes Pancreáticos/patología , Islotes Pancreáticos/virología , Masculino , Ratas , Ratas Endogámicas Lew , Ratas Wistar , Reproducibilidad de los Resultados
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