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1.
ACS Omega ; 4(19): 18049-18060, 2019 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-31720508

RESUMEN

Synthetic peptides mimicking the binding site of fertilin ß to its receptor, integrin α6ß1, were shown to inhibit sperm-egg fusion when added to in vitro media. In contrast, the synthetic cyclic hexapeptide, cyclo(Cys1-Ser2-Phe3-Glu4-Glu5-Cys6), named as cFEE, proved to stimulate gamete fusion. Owing to its biological specificity, this hexapeptide could help improve the in vitro fertilization pregnancy rate in human. In an attempt to establish the structure-activity relationship of cFEE, its structural dynamics was herein analyzed by means of ultraviolet circular dichroism (UV-CD) and Raman scattering. The low concentration CD profile in water, containing mainly a deep minimum at ∼202 nm, is consistent with a rather unordered chain. However, an ordering trend of the peptide loop has been observed in a less polar solvent such as methanol, where the UV-CD signal shape is formed by a double negative marker at ∼202/215 nm, indicating the presence of a type-II' ß-turn. Raman spectra recorded in aqueous samples upon a 100-fold concentration increase, still showed an important population (∼30%) of the disordered structure. The structural flexibility of the disulfide bridge was confirmed by the Raman markers arising from the Cys1-Cys6 disulfide bond-stretch motions. Density functional theory calculations highlighted the formation of the type-II' ß-turn on the four central residues of cFEE (i.e., -Ser2-Phe3-Glu4-Glu5-) either with a left- or with a right-handed disulfide. The structure with a left-handed S-S bond, however, appears to be more stable.

2.
Mol Ther Methods Clin Dev ; 13: 303-309, 2019 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-30911587

RESUMEN

Although the risk of developing lymphoma has decreased in the highly active antiretroviral therapy era, this cancer remains the major cause of mortality in HIV-infected patients. Autologous hematopoietic stem cell transplantation (ASCT) outcome does not differ for HIV-infected versus HIV-uninfected patients. We propose to develop a new treatment for HIV-associated high-risk lymphoma based on autologous transplantation of two genetically modified products: CD4+ T lymphocytes and CD34+ hematopoietic stem cells (HSPCs). The cells will be transduced ex vivo with the Cal-1 lentiviral vector encoding for both a short hairpin RNA (shRNA) against CCR5 (sh5) and the HIV-1 fusion inhibitor C46. The transduced cells will be resistant to HIV infection by two complementary mechanisms: impaired binding of the virus to the cellular CCR5 co-receptor and decreased fusion of the virus as C46 interacts with gp41 and inhibits HIV infection. This phase I/II pilot study, also entitled GENHIV, will involve two French participating centers: Saint Louis Hospital and Necker Hospital in Paris. We plan to enroll five HIV-1-infected patients presenting with high-risk lymphoma and require a treatment with ASCT. The primary objective of this study is to evaluate the safety, feasibility, and success of engraftment of Cal-1 gene-transduced CD4+ T lymphocytes and CD34+ HSPCs.

3.
J Am Coll Cardiol ; 71(4): 429-438, 2018 01 30.
Artículo en Inglés | MEDLINE | ID: mdl-29389360

RESUMEN

BACKGROUND: In addition to scalability, human embryonic stem cells (hESCs) have the unique advantage of allowing their directed differentiation toward lineage-specific cells. OBJECTIVES: This study tested the feasibility of leveraging the properties of hESCs to generate clinical-grade cardiovascular progenitor cells and assessed their safety in patients with severe ischemic left ventricular dysfunction. METHODS: Six patients (median age 66.5 years [interquartile range (IQR): 60.5 to 74.7 years]; median left ventricular ejection fraction 26% [IQR: 22% to 32%]) received a median dose of 8.2 million (IQR: 5 to 10 million) hESC-derived cardiovascular progenitors embedded in a fibrin patch that was epicardially delivered during a coronary artery bypass procedure. The primary endpoint was safety at 1 year and focused on: 1) cardiac or off-target tumor, assessed by imaging (computed tomography and fluorine-18 fluorodeoxyglucose positron emission tomography scans); 2) arrhythmias, detected by serial interrogations of the cardioverter-defibrillators implanted in all patients; and 3) alloimmunization, assessed by the presence of donor-specific antibodies. Patients were followed up for a median of 18 months. RESULTS: The protocol generated a highly purified (median 97.5% [IQR: 95.5% to 98.7%]) population of cardiovascular progenitors. One patient died early post-operatively from treatment-unrelated comorbidities. All others had uneventful recoveries. No tumor was detected during follow-up, and none of the patients presented with arrhythmias. Three patients developed clinically silent alloimmunization. All patients were symptomatically improved with an increased systolic motion of the cell-treated segments. One patient died of heart failure after 22 months. CONCLUSIONS: This trial demonstrates the technical feasibility of producing clinical-grade hESC-derived cardiovascular progenitors and supports their short- and medium-term safety, thereby setting the grounds for adequately powered efficacy studies. (Transplantation of Human Embryonic Stem Cell-derived Progenitors in Severe Heart Failure [ESCORT]; NCT02057900).


Asunto(s)
Puente de Arteria Coronaria , Células Madre Embrionarias Humanas/trasplante , Isquemia Miocárdica/terapia , Trasplante de Células Madre/métodos , Disfunción Ventricular Izquierda/terapia , Anciano , Estudios de Cohortes , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Isquemia Miocárdica/complicaciones , Isquemia Miocárdica/mortalidad , Tasa de Supervivencia , Resultado del Tratamiento , Disfunción Ventricular Izquierda/complicaciones , Disfunción Ventricular Izquierda/mortalidad
4.
Eur Heart J ; 36(30): 2011-7, 2015 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-25990469

RESUMEN

AIMS: Comparative studies suggest that stem cells committed to a cardiac lineage are more effective for improving heart function than those featuring an extra-cardiac phenotype. We have therefore developed a population of human embryonic stem cell (ESC)-derived cardiac progenitor cells. METHODS AND RESULTS: Undifferentiated human ESCs (I6 line) were amplified and cardiac-committed by exposure to bone morphogenetic protein-2 and a fibroblast growth factor receptor inhibitor. Cells responding to these cardio-instructive cues express the cardiac transcription factor Isl-1 and the stage-specific embryonic antigen SSEA-1 which was then used to purify them by immunomagnetic sorting. The Isl-1(+) SSEA-1(+) cells were then embedded into a fibrin scaffold which was surgically delivered onto the infarct area in a 68-year-old patient suffering from severe heart failure [New York Heart Association [NYHA] functional Class III; left ventricular ejection fraction (LVEF): 26%]. A coronary artery bypass was performed concomitantly in a non-infarcted area. The implanted cells featured a high degree of purity (99% were SSEA-1(+)), had lost the expression of Sox-2 and Nanog, taken as markers for pluripotency, and strongly expressed Isl-1. The intraoperative delivery of the patch was expeditious. The post-operative course was uncomplicated either. After 3 months, the patient is symptomatically improved (NYHA functional Class I; LVEF: 36%) and a new-onset contractility is echocardiographically evident in the previously akinetic cell/patch-treated, non-revascularized area. There have been no complications such as arrhythmias, tumour formation, or immunosuppression-related adverse events. CONCLUSION: This observation demonstrates the feasibility of generating a clinical-grade population of human ESC-derived cardiac progenitors and combining it within a tissue-engineered construct. While any conclusion pertaining to efficacy would be meaningless, the patient's functional outcome yet provides an encouraging hint. Beyond this case, the platform that has been set could be useful for generating different ESC-derived lineage-specific progenies.


Asunto(s)
Insuficiencia Cardíaca/terapia , Células Madre Embrionarias Humanas/trasplante , Femenino , Humanos , Persona de Mediana Edad , Isquemia Miocárdica/terapia , Andamios del Tejido , Resultado del Tratamiento , Disfunción Ventricular Izquierda/terapia
5.
Eur Heart J ; 36(12): 743-50, 2015 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-24835485

RESUMEN

AIM: There is now compelling evidence that cells committed to a cardiac lineage are most effective for improving the function of infarcted hearts. This has been confirmed by our pre-clinical studies entailing transplantation of human embryonic stem cell (hESC)-derived cardiac progenitors in rat and non-human primate models of myocardial infarction. These data have paved the way for a translational programme aimed at a phase I clinical trial. METHODS AND RESULTS: The main steps of this programme have included (i) the expansion of a clone of pluripotent hESC to generate a master cell bank under good manufacturing practice conditions (GMP); (ii) a growth factor-induced cardiac specification; (iii) the purification of committed cells by immunomagnetic sorting to yield a stage-specific embryonic antigen (SSEA)-1-positive cell population strongly expressing the early cardiac transcription factor Isl-1; (iv) the incorporation of these cells into a fibrin scaffold; (v) a safety assessment focused on the loss of teratoma-forming cells by in vitro (transcriptomics) and in vivo (cell injections in immunodeficient mice) measurements; (vi) an extensive cytogenetic and viral testing; and (vii) the characterization of the final cell product and its release criteria. The data collected throughout this process have led to approval by the French regulatory authorities for a first-in-man clinical trial of transplantation of these SSEA-1(+) progenitors in patients with severely impaired cardiac function. CONCLUSION: Although several facets of this manufacturing process still need to be improved, these data may yet provide a useful platform for the production of hESC-derived cardiac progenitor cells under safe and cost-effective GMP conditions.


Asunto(s)
Células Madre Embrionarias Humanas/trasplante , Separación Inmunomagnética/métodos , Bancos de Tejidos/organización & administración , Animales , Tratamiento Basado en Trasplante de Células y Tejidos/métodos , Ensayos Clínicos Fase I como Asunto , Análisis Citogenético , Estudios de Evaluación como Asunto , Humanos , Ratones SCID , Miocitos Cardíacos/citología , Miocitos Cardíacos/trasplante , Conservación de Tejido/métodos , Andamios del Tejido
6.
Lancet Neurol ; 13(2): 150-8, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24411709

RESUMEN

BACKGROUND: Creutzfeldt-Jakob disease (CJD) is a fatal, untreatable prion encephalopathy. Previous studies showed that doxycycline is effective in in-vitro and in-vivo models of disease, and patients with CJD who received compassionate treatment with doxycycline showed increased survival time compared with historical series. We therefore did a randomised, double-blind study of doxycycline versus placebo in CJD. METHODS: We recruited patients older than 18 years old who had a diagnosis of definite or probable sporadic CJD or genetic forms of the disease via Italian reference centres and the French national referral system. Patients were randomly assigned (ratio 1:1) to receive oral doxycycline (100 mg daily) or placebo under double-blind conditions from the day of randomisation to death. Centralised randomisation was done independently of enrolment or evaluation of patients using a minimisation method in Italy and a simple randomisation in France. Participants, caregivers, and clinicians were masked to group assignment. The primary efficacy variable was the survival time from randomisation. Interim analyses were planned to detect a significant effect of treatment as early as possible. This trial is registered with EudraCT, 2006-001858-27 for the Italian study and 2007-005553-34 for the French study. FINDINGS: From April 12, 2007, to Aug 19, 2010, in Italy, and from Jan 30, 2009, to Jan 10, 2012, in France, 121 patients with CJD were enrolled in the study, 62 of whom were randomly assigned to the treatment group and 59 to the placebo group. The first interim analysis showed absence of superiority of doxycycline compared with placebo, and the trial was stopped for futility. Efficacy analyses did not show significant differences between patients treated with doxycycline and placebo with regard to survival times (HR 1.1, 95% CI 0.8-1.7, p=0.50). Serious adverse events were judged not to be related to treatment, whereas a relation was deemed probable or possible for five non-serious adverse events that occurred in each treatment group. INTERPRETATION: Doxycycline at a dose of 100 mg per day was well tolerated but did not significantly affect the course of CJD, at variance with the results of previous observational studies. Our experience could be useful in the design of large multinational controlled trials of potential anti-prion molecules in this rare disease. FUNDING: Agenzia Italiana Farmaco, Italian Ministry of Health, AIEnP, and French Ministry of Health.


Asunto(s)
Síndrome de Creutzfeldt-Jakob/tratamiento farmacológico , Doxiciclina/farmacología , Anciano , Síndrome de Creutzfeldt-Jakob/genética , Síndrome de Creutzfeldt-Jakob/mortalidad , Método Doble Ciego , Doxiciclina/administración & dosificación , Doxiciclina/efectos adversos , Terminación Anticipada de los Ensayos Clínicos , Femenino , Humanos , Masculino , Inutilidad Médica , Persona de Mediana Edad , Insuficiencia del Tratamiento
7.
Eur J Endocrinol ; 166(2): 333-9, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22048969

RESUMEN

CONTEXT: Congenital hyperinsulinism (HI) is a common cause of hypoglycemia in infancy. The medical treatment of diazoxide-unresponsive HI is based on a somatostatin analogue. OBJECTIVE: This study aims at replacing three daily s.c. octreotide (Sandostatin, Novartis) injections by a single and monthly i.m. injection of long-acting release (LAR) octreotide (Sandostatin LP, Novartis) in HI patients. SUBJECTS AND METHOD: LAR octreotide was injected every 4 weeks during 6 months and s.c. octreotide injections were stopped after the third injection of LAR octreotide. After this 6-month study, LAR octreotide was continued, with an average follow-up of 17 months. Ten HI pediatric patients unresponsive to diazoxide and currently treated with s.c. octreotide were included in the trial. Glycemias and other parameters (HbA1c, IGF1, height, weight, quality of life (QoL), and satisfaction) were monitored at each monthly visit. RESULTS: For all ten patients, glycemias were maintained in the usual range, HbAlc (mean 5.5%; 95% CI: 4.6-6.2) and IGF1 (mean 89.7 ng/ml; 95% CI: 26-153) were unchanged. Patients gained height significantly (mean 2.7 cm; 95% CI: 1.9-3.4) and no side effect was noted during the study and the later follow-up. Plasma octreotide levels were stable under LAR octreotide. Parents' questionnaires of general satisfaction were highly positive whereas children's QoL evaluation remained unchanged. CONCLUSION: In these diazoxide-unresponsive HI patients, LAR octreotide was efficient, well tolerated and contributed to a clear simplification of the medical care.


Asunto(s)
Hiperinsulinismo Congénito/tratamiento farmacológico , Octreótido/administración & dosificación , Transportadoras de Casetes de Unión a ATP/genética , Niño , Preescolar , Hiperinsulinismo Congénito/sangre , Hiperinsulinismo Congénito/genética , Hiperinsulinismo Congénito/metabolismo , Preparaciones de Acción Retardada , Femenino , Estudios de Seguimiento , Fármacos Gastrointestinales/administración & dosificación , Fármacos Gastrointestinales/efectos adversos , Humanos , Lactante , Inyecciones Intramusculares/efectos adversos , Inyecciones Subcutáneas/efectos adversos , Masculino , Octreótido/efectos adversos , Octreótido/sangre , Octreótido/farmacocinética , Canales de Potasio de Rectificación Interna/genética , Receptores de Droga/genética , Receptores de Sulfonilureas , Resultado del Tratamiento
8.
Bioorg Med Chem ; 12(5): 1129-39, 2004 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-14980625

RESUMEN

New imidazo[1,2-a]quinoxaline derivatives have been synthesised by condensation of an appropriate alpha-aminoalcohol with a quinoxaline followed by intramolecular cyclisation and nucleophilic substitutions. Their phosphodiesterase inhibitory activities have been assessed on a preparation of the PDE4 isoform purified from a human alveolar epithelial cell line (A549). These studies showed potent inhibitory properties that emphasize the importance of a methyl amino group at position 4 and a weakly hindered group at position 1.


Asunto(s)
3',5'-AMP Cíclico Fosfodiesterasas/antagonistas & inhibidores , Quinoxalinas/síntesis química , Quinoxalinas/farmacología , 3',5'-AMP Cíclico Fosfodiesterasas/aislamiento & purificación , Línea Celular , Fosfodiesterasas de Nucleótidos Cíclicos Tipo 4 , Diseño de Fármacos , Células Epiteliales/enzimología , Humanos , Inflamación/prevención & control , Concentración 50 Inhibidora , Pulmón/citología , Relación Estructura-Actividad
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