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1.
Prog Urol ; 30(12): 655-662, 2020 Oct.
Artículo en Francés | MEDLINE | ID: mdl-32814659

RESUMEN

OBJECTIVE: The objective of this study was to analyze early, late complications and outcomes following expended criteria donors (ECD) kidney transplantation compared to standard donors. MATERIALS AND METHODS: We performed a retrospective study including 470 patients who received a kidney transplant between 2005 and 2016. Expended criteria donors were defined following the United Network of Organ Sharing criteria. In each group, length of stay, delayed graft function, surgical site infection, acute rejection, surgical complications by type and according to Clavien and Dindo classification were analyzed in univariate and multivariate analysis. The impact of ECD transplant on transplant and patient survival was assessed using a Cox proportional regression model. RESULTS: One hundred and ninety seven (41.9%) patients received ECD kidney. The mean follow-up was 61,4 months (22.4-93.89). Patients with ECD transplant presented more delayed graft function (HR=2.1 (1.1-3.68), P=0.008) but the rate of complications including surgical complications was not different. Patients and transplant survival were decreased in ECD transplant group (P=0.005 et 0.001 respectively). In multivariate analysis ECD kidney was an independent factor only associated with decreased transplant survival (HR=1.81 (1.1-2.98), P=0.029) but not with patient survival. CONCLUSION: ECD kidney transplantation was not associated with increased postoperative complications but a higher rate of delayed graft function. Nevertheless, it was associated with a decreased transplant survival. The use of pulsatile perfusion machine for explanted criteria transplant should be evaluated to improve these results.


Asunto(s)
Selección de Donante , Donantes de Tejidos , Supervivencia de Injerto , Humanos , Complicaciones Posoperatorias/epidemiología , Estudios Retrospectivos , Resultado del Tratamiento
2.
Fungal Genet Biol ; 77: 12-21, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25732380

RESUMEN

Alder decline has been a problem along European watercourses since the early 1990s. Hybridization was identified as the main cause of this emerging disease. Indeed, the causal agent, a soil-borne pathogen named Phytophthora alni subsp. alni (Paa) is the result of interspecific hybridization between two taxa, Phytophthora alni subsp. multiformis (Pam) and Phytophthora alni subsp. uniformis (Pau), initially identified as subspecies of Paa. The aim of this work was to characterize the ploidy level within the P. alni complex that is presently poorly understood. For that, we used two complementary approaches for a set of 31 isolates of Paa, Pam and Pau: (i) quantification of allele copy number of three single-copy nuclear genes using allele-specific real-time PCR and (ii) comparison of the genome size estimated by flow cytometry. Relative quantification of alleles of the three single-copy genes showed that the copy number of a given allele in Paa was systematically half that of its parents Pau or Pam. Moreover, DNA content estimated by flow cytometry in Paa was equal to half the sum of those in Pam and Pau. Our results therefore suggest that the hybrid Paa is an allotriploid species, containing half of the genome of each of its parents Pam and Pau, which in turn are considered to be allotetraploid and diploid, respectively. Paa thus results from a homoploid speciation process. Based on published data and on results from this study, a new formal taxonomic name is proposed for the three taxa Paa, Pam and Pau which are raised to species status and renamed P. ×alni, P. ×multiformis and P. uniformis, respectively.


Asunto(s)
Quimera/genética , Genoma , Phytophthora/clasificación , Phytophthora/genética , Poliploidía , Alelos , Alnus/microbiología , Quimera/clasificación , Phytophthora/patogenicidad
3.
Rev Med Suisse ; 10(420): 526-9, 2014 Mar 05.
Artículo en Francés | MEDLINE | ID: mdl-24701670

RESUMEN

Subclinical hypothyroidism is a common condition, and its prevalence increases with age. Currently, guidelines regarding the screening and treatment of subclinical hypothyroidism are controversial. An international survey of general practitioners (GPs), to which Swiss GPs also contributed, showed large inter-country variations in treatment strategies for subclinical hypothyroidism. These differences are mainly explained by the lack of strong evidence for the management of this condition. The European randomized-controlled clinical trial TRUST should help clarify recommendations for screening and thyroxin replacement for the elderly with subclinical hypothyroidism. Working in close collaboration with GPs in Switzerland for the recruitment of patients will ensure that the findings from this study will be applicable to primary care settings.


Asunto(s)
Hipotiroidismo/tratamiento farmacológico , Pautas de la Práctica en Medicina/estadística & datos numéricos , Terapia de Reemplazo de Hormonas , Humanos , Médicos de Familia , Ensayos Clínicos Controlados Aleatorios como Asunto , Encuestas y Cuestionarios , Suiza , Tiroxina/uso terapéutico
4.
J Urol ; 188(3): 943-7, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22819105

RESUMEN

PURPOSE: We preoperatively assessed neurovesical function and spinal cord function in children with anorectal malformations. In cases of neurovesical dysfunction we looked for an association with vertebral malformation or myelodysplasia. MATERIALS AND METHODS: We prospectively evaluated 80 children with anorectal malformations via preoperative urodynamics and magnetic resonance imaging of the spine. Bladder compliance and volume, detrusor activity and vesicosphincteric synergy during voiding allowed urodynamic evaluation. Results were reported according to Wingspread and Krickenbeck classifications of anorectal malformations. RESULTS: Urodynamic findings were pathological in 14 children (18%). Pathological evaluations did not seem related to type of fistula or level of anorectal malformation. Vertebral anomalies were seen in 34 patients (43%) and myelodysplasia in 16 (20%). Neither vertebral anomaly nor myelodysplasia seemed associated with type of fistula or severity of anorectal malformation. Of 14 children with pathological urodynamics no vertebral anomaly or myelodysplasia was found in 7. Of 66 children with normal urodynamics 40 presented with vertebral or spinal malformation. CONCLUSIONS: Lower urinary tract dysfunction is common in patients with anorectal malformations. Normal spine or spinal cord does not exclude neurovesical dysfunction. Myelodysplasia or vertebral anomaly does not determine lower urinary tract dysfunction. Thus, we recommend preoperative urodynamic assessment of the bladder and magnetic resonance imaging of the spine in children with anorectal malformations.


Asunto(s)
Anomalías Múltiples/fisiopatología , Canal Anal/anomalías , Ano Imperforado/fisiopatología , Defectos del Tubo Neural/fisiopatología , Recto/anomalías , Vejiga Urinaria Neurogénica/fisiopatología , Urodinámica , Ano Imperforado/complicaciones , Femenino , Humanos , Lactante , Imagen por Resonancia Magnética , Masculino , Defectos del Tubo Neural/complicaciones , Cuidados Preoperatorios , Estudios Prospectivos , Vejiga Urinaria Neurogénica/etiología
5.
Cancer Radiother ; 26(1-2): 404-410, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34969621

RESUMEN

Radiotherapy in patients with cardiac implantable electronic device such as pacemakers or defibrillators, is a clinical situation that is becoming increasingly common. There is a risk of interaction between the magnetic field induced by accelerators and the cardiac implantable electronic device, but also a risk of device dysfunction due to direct and/or indirect irradiation if the cardiac implantable electronic device is in the field of treatment. The risk can be dose-dependent, but it is most often independent of the total dose and occurs randomly in case of neutron production (stochastic effect). The presence of this type of device is therefore described as a contraindication for radiotherapy by the French national agency for the safety of medicines and health products (Agence nationale de sécurité du médicament et des produits de santé, ANSM). Nevertheless, since radiotherapy is often possible, it is advisable to respect the recommendations of good practice, in particular the eligibility criteria, the monitoring modalities before, during and after irradiation according to the type of treatment, the dose and the characteristics of the cardiac implantable electronic device. It is sometimes necessary to discuss repositioning the device and/or modifying the treatment plan to minimize the risk of cardiac implantable electronic device dysfunction. We present the update of the recommendations of the French society of oncological radiotherapy on in patients with cardiac implantable electronic device.


Asunto(s)
Dispositivos de Terapia de Resincronización Cardíaca , Consenso , Desfibriladores Implantables , Neoplasias/radioterapia , Lista de Verificación , Contraindicaciones de los Procedimientos , Francia , Humanos , Campos Magnéticos , Imagen por Resonancia Magnética , Microcomputadores , Neoplasias/diagnóstico por imagen , Diseño de Prótesis , Falla de Prótesis/efectos de la radiación , Dosis de Radiación , Oncología por Radiación , Radioterapia/efectos adversos , Factores de Riesgo , Sociedades Médicas , Tomografía Computarizada por Rayos X
6.
Mol Ecol ; 20(13): 2739-55, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21627704

RESUMEN

Wild and cultivated plants represent very different habitats for pathogens, especially when cultivated plants bear qualitative resistance genes. Here, we investigated to what extent the population genetic structure of a plant pathogenic fungus collected on its wild host can be impacted by the deployment of resistant cultivars. We studied one of the main poplar diseases, poplar rust, caused by the fungus Melampsora larici-populina. A thousand and fifty individuals sampled from several locations in France were phenotyped for their virulence profile (ability to infect or not the most deployed resistant cultivar 'Beaupré'), and a subset of these was genotyped using 25 microsatellite markers. Bayesian assignment tests on genetic data clustered the 476 genotyped individuals into three genetic groups. Group 1 gathered most virulent individuals and displayed evidence for selection and drastic demographic changes resulting from breakdown of the poplar cultivar 'Beaupré'. Group 2 comprised individuals corresponding to ancestral populations of M. larici-populina naturally occurring in the native range. Group 3 displayed the hallmarks of strict asexual reproduction, which has never previously been demonstrated in this species. We discuss how poplar cultivation has influenced the spatial and genetic structure of this plant pathogenic fungus, and has led to the spread of virulence alleles (gene swamping) in M. larici-populina populations evolving on the wild host.


Asunto(s)
Basidiomycota/genética , Estructuras Genéticas/genética , Enfermedades de las Plantas/microbiología , Populus/microbiología , Alelos , Basidiomycota/aislamiento & purificación , Basidiomycota/patogenicidad , Teorema de Bayes , Cruzamiento , Análisis por Conglomerados , Demografía , Francia , Flujo Génico , Variación Genética , Genética de Población , Genotipo , Repeticiones de Microsatélite/genética , Mutación , Fenotipo , Virulencia/genética
7.
Rev Med Suisse ; 6(249): 1022-5, 2010 May 19.
Artículo en Francés | MEDLINE | ID: mdl-20568368

RESUMEN

The prevalence of overweight and obesity in children is increasing. A growing number of children are thus suffering from complications of obesity. Contributing factors can be found on an individual level as well as in the familial and social environment of affected children. Currently there is no single evidence-based treatment strategy available. Studies from family practice are scarce. Multimodal, long-term, easily accessible treatments as offered in family practice are promising and likely to be cost-effective. The sustainability of these changes in behavior still needs to be demonstrated.


Asunto(s)
Obesidad , Sobrepeso , Adolescente , Adulto , Factores de Edad , Niño , Consejo , Dieta , Medicina Familiar y Comunitaria , Femenino , Alimentos , Promoción de la Salud , Humanos , Estilo de Vida , Masculino , Obesidad/epidemiología , Obesidad/prevención & control , Obesidad/terapia , Sobrepeso/epidemiología , Sobrepeso/prevención & control , Sobrepeso/terapia , Factores de Riesgo , Factores Sexuales , Suiza , Televisión , Caminata
8.
Science ; 182(4107): 83-5, 1973 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-17829813

RESUMEN

Students' ratings of their instructors in undergraduate classes in calculus were correlated with class performance on a common final examination. Ratings on several instructional factors were highly related to class performance even though they appeared to be independent of the students' own grades.

9.
Science ; 155(3767): 1281-2, 1967 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-4381178

RESUMEN

Rats administered 20 milligrams of magnesium pemoline per kilo gram of body weight learned to avoid shock in a jump-out apparatus in fewer trials than did controls. However, the results suggested that the principal effect of the drug was to facilitate the avoidance behavior of those animals that tended to "freeze" in response to electric grid shock. No differences in retention were observed between experimental and control animals that had achieved equal levels of learnine.


Asunto(s)
Reacción de Prevención/efectos de los fármacos , Estimulantes del Sistema Nervioso Central/farmacología , Condicionamiento Psicológico/efectos de los fármacos , Animales , Condicionamiento Clásico , Estimulación Eléctrica , Masculino , Pemolina/farmacología , Ratas
10.
Science ; 228(4699): 541-5, 1985 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-2984773

RESUMEN

In the recent literature on nucleoside phosphorothioate anions the structural formulas show a double bond between phosphorus and sulfur and a single bond between phosphorus and oxygen with a negative charge localized on oxygen. However, a review of physical data on these compounds shows the reverse to be the case; that is, in phosphorothioate anions the P-S bond is a single bond with a negative charge localized on sulfur, while the P-O bond order for exocyclic and nonbridging oxygens is greater than 1, approaching 2 in O-alkyl phosphorothioate monoanions and O,O-dialkyl phosphorothioates. The P-O bond orders in phosphorothioate dianions and trianions approach 1 1/2 and 1 1/3, respectively, owing to delocalization of negative charge among two or three oxygens. These conclusions are based on bond lengths obtained from x-ray crystallographic data and electron diffraction, the magnitudes of the effects of 18O on the 31P-nuclear magnetic resonance chemical shifts of phosphorus in nucleoside [18O]phosphorothioates, the pH-dependence of 17O-NMR chemical shifts in [17O]phosphate and [17O]thiophosphate, the vibrational spectra of thiophosphate di- and trianions, and the pKa (dissociation constant) values for phosphoric and thiophosphoric acids.


Asunto(s)
Tionucleótidos , Fenómenos Químicos , Química , Química Física , AMP Cíclico/metabolismo , Espectroscopía de Resonancia Magnética , Fosfatos/metabolismo , Ácidos Fosfóricos/metabolismo , Tionucleótidos/metabolismo
11.
Science ; 264(5167): 1927-30, 1994 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-7661899

RESUMEN

Spectroscopic properties of chymotrypsin and model compounds indicate that a low-barrier hydrogen bond participates in the mechanism of serine protease action. A low-barrier hydrogen bond between N delta 1 of His57 and the beta-carboxyl group of Asp102 in chymotrypsin can facilitate the formation of the tetrahedral adduct, and the nuclear magnetic resonance properties of this proton indicate that it is a low-barrier hydrogen bond. These conclusions are supported by the chemical shift of this proton, the deuterium isotope effect on the chemical shift, and the properties of hydrogen-bonded model compounds in organic solvents, including the hydrogen bond in cis-urocanic acid, in which the imidazole ring is internally hydrogen-bonded to the carboxyl group.


Asunto(s)
Quimotripsina/química , Serina Endopeptidasas/química , Ácido Aspártico/química , Catálisis , Quimotripsina/metabolismo , Histidina/química , Enlace de Hidrógeno , Concentración de Iones de Hidrógeno , Espectroscopía de Resonancia Magnética , Maleatos/química , Malonatos/química , Serina/química , Serina Endopeptidasas/metabolismo , Temperatura , Ácido Urocánico/química
12.
Nat Commun ; 10(1): 5162, 2019 11 14.
Artículo en Inglés | MEDLINE | ID: mdl-31727884

RESUMEN

Resonant enhancement of spin Seebeck effect (SSE) due to phonons was recently discovered in Y[Formula: see text]Fe[Formula: see text]O[Formula: see text] (YIG). This effect is explained by hybridization between the magnon and phonon dispersions. However, this effect was observed at low temperatures and high magnetic fields, limiting the scope for applications. Here we report observation of phonon-resonant enhancement of SSE at room temperature and low magnetic field. We observe in Lu[Formula: see text]BiFe[Formula: see text]GaO[Formula: see text] an enhancement 700% greater than that in a YIG film and at very low magnetic fields around 10[Formula: see text] T, almost one order of magnitude lower than that of YIG. The result can be explained by the change in the magnon dispersion induced by magnetic compensation due to the presence of non-magnetic ion substitutions. Our study provides a way to tune the magnon response in a crystal by chemical doping, with potential applications for spintronic devices.

13.
Biomaterials ; 206: 41-48, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30925287

RESUMEN

Stress urinary incontinence (SUI) is a life changing condition, affecting 20 million women worldwide. In this study, we developed a bioactive, injectable bulking agent that consists of Permacol™ (Medtronic, Switzerland) and recombinant insulin like growth factor-1 conjugated fibrin micro-beads (fib_rIGF-1) for its bulk stability and capacity to induce muscle regeneration. Therefore, Permacol™ formulations were injected in the submucosal space of rabbit bladders. The ability of a bulking material to form a stable and muscle-inducing bulk represents for us a promising therapeutic approach to achieve a long-lasting treatment for SUI. The fib_rIGF-1 showed no adverse effect on human smooth muscle cell metabolic activity and viability in vitro based on AlamarBlue assays and Live/Dead staining. Three months after injection of fib_rIGF-1 together with Permacol™ into the rabbit bladder wall, we observed a smooth muscle tissue like formation within the injected materials. Positive staining for alpha smooth muscle actin, calponin, and caldesmon demonstrated a contractile phenotype of the newly formed smooth muscle tissue. Moreover, the fib_rIGF-1 treated group also improved the neovascularization at the injection site, confirmed by CD31 positive staining compared to bulks made of PermacolTM only. The results of this study encourage us to further develop this injectable, bioactive bulking material towards a future therapeutic approach for a minimal invasive and long-lasting treatment of SUI.


Asunto(s)
Materiales Biocompatibles/uso terapéutico , Incontinencia Urinaria de Esfuerzo/terapia , Animales , Materiales Biocompatibles/química , Femenino , Fibrina/química , Humanos , Inmunohistoquímica , Ratones , Miocitos del Músculo Liso/citología , Miocitos del Músculo Liso/metabolismo , Conejos , Incontinencia Urinaria de Esfuerzo/metabolismo , Sistema Urinario/citología , Sistema Urinario/metabolismo
14.
Rev Med Suisse ; 4(139): 61-6, 2008 Jan 09.
Artículo en Francés | MEDLINE | ID: mdl-18251218

RESUMEN

This article summarizes the medical progress achieved in 2 frequent and 2 rare pathologies: 1. Cryptorchidism should be operated around 12 months of age and hormonal treatment abandoned in order to maintain fertility and avoid development of testicular tumors. 2. For the treatment of streptococcal pharyngitis oral cephalosporins for 4 to 5 days are equivalent to a Penicillin treatment of 10 days. 3. Thanks to carvedilol (a beta-blocker agent), levosimendan (a calcium sensibiliser) and nesiritide (an analog to the natriuretic peptide) a new hormonal approach to cardiac failure is possible. 4. Corticosteroids allow to improve quality of live and life expectancy in Duchenne muscular dystrophy, provided treatment starts early and a multidisciplinary approach is assured.


Asunto(s)
Pediatría , Niño , Criptorquidismo/cirugía , Insuficiencia Cardíaca/tratamiento farmacológico , Humanos , Masculino , Distrofia Muscular de Duchenne/tratamiento farmacológico , Faringitis/tratamiento farmacológico , Faringitis/microbiología , Infecciones Estreptocócicas/tratamiento farmacológico
15.
Sci Rep ; 8(1): 10057, 2018 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-29968749

RESUMEN

There is a need for efficient and "off-the-shelf" grafts in urethral reconstructive surgery. Currently available surgical techniques require harvesting of grafts from autologous sites, with increased risk of surgical complications and added patient discomfort. Therefore, a cost-effective and cell-free graft with adequate regenerative potential has a great chance to be translated into clinical practice. Tubular cell-free collagen grafts were prepared by varying the collagen density and fiber distribution, thereby creating a polarized low fiber density collagen graft (LD-graft). A uniform, high fiber density collagen graft (HD-graft) was engineered as a control. These two grafts were implanted to bridge a 2 cm long iatrogenic urethral defect in a rabbit model. Histology revealed that rabbits implanted with the LD-graft had a better smooth muscle regeneration compared to the HD-graft. The overall functional outcome assessed by contrast voiding cystourethrography showed patency of the urethra in 90% for the LD-graft and in 66.6% for the HD-graft. Functional regeneration of the rabbit implanted with the LD-graft could further be demonstrated by successful mating, resulting in healthy offspring. In conclusion, cell-free low-density polarized collagen grafts show better urethral regeneration than high-density collagen grafts.


Asunto(s)
Colágeno/metabolismo , Ingeniería de Tejidos/métodos , Uretra/patología , Animales , Fibras de la Dieta , Matriz Extracelular , Masculino , Modelos Animales , Músculo Liso , Conejos , Procedimientos de Cirugía Plástica , Regeneración , Trasplantes/metabolismo , Trasplantes/cirugía , Uretra/trasplante
16.
Acta Biomater ; 67: 156-166, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29197579

RESUMEN

Endoscopic injection of bulking agents has been widely used to treat urinary incontinence, often due to urethral sphincter complex insufficiency. The aim of the study was to develop a novel injectable bioactive collagen-fibrin bulking agent restoring long-term continence by functional muscle tissue regeneration. Fibrin micro-beads were engineered using a droplet microfluidic system. They had an average diameter of 140 µm and recombinant fibrin-binding insulin-like growth factor-1 (α2PI1-8-MMP-IGF-1) was covalently conjugated to the beads. A plasmin fibrin degradation assay showed that 72.5% of the initial amount of α2PI1-8-MMP-IGF-1 loaded into the micro-beads was retained within the fibrin micro-beads. In vitro, the growth factor modified fibrin micro-beads enhanced cell attachment and the migration of human urinary tract smooth muscle cells, however, no change of the cellular metabolic activity was seen. These bioactive micro-beads were mixed with genipin-crosslinked homogenized collagen, acting as a carrier. The collagen concentration, the degree of crosslinking, and the mechanical behavior of this bioactive collagen-fibrin injectable were comparable to reference samples. This novel injectable showed no burst release of the growth factor, had a positive effect on cell behavior and may therefore induce smooth muscle regeneration in vivo, necessary for the functional treatment of stress and other urinary incontinences. STATEMENT OF SIGNIFICANCE: Urinary incontinence is involuntary urine leakage, resulting from a deficient function of the sphincter muscle complex. Yet there is no functional cure for this devastating condition using current treatment options. Applied physical and surgical therapies have limited success. In this study, a novel bioactive injectable bulking agent, triggering new muscle regeneration at the injection site, has been evaluated. This injectable consists of cross-linked collagen and fibrin micro-beads, functionalized with bound insulin-like growth factor-1 (α2PI1-8-MMP-IGF-1). These bioactive fibrin micro-beads induced human smooth muscle cell migration in vitro. Thus, this injectable bulking agent is apt to be a good candidate for regeneration of urethral sphincter muscle, ensuring a long-lasting treatment for urinary incontinence.


Asunto(s)
Colágeno/química , Reactivos de Enlaces Cruzados/química , Fibrina/uso terapéutico , Inyecciones , Microfluídica/métodos , Microesferas , Incontinencia Urinaria/tratamiento farmacológico , Animales , Movimiento Celular , Supervivencia Celular , Módulo de Elasticidad , Fibrina/farmacología , Humanos , Factor I del Crecimiento Similar a la Insulina , Miocitos del Músculo Liso/metabolismo , Miocitos del Músculo Liso/patología , Tamaño de la Partícula , Ratas , Reología , Incontinencia Urinaria/patología , Viscosidad
17.
Plant Dis ; 91(10): 1359, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30780541

RESUMEN

In April 2002, Phytophthora ramorum was associated with twig blight and brown spots on Rhododendron spp. leaves from a nursery in France. The isolate was identified by its morphological characters on V8 agar: slow growth, deciduous and semipapillate sporangia, and abundant production of large chlamydospores (3). The identification was confirmed by ITS rDNA sequencing. During 2002, P. ramorum was also isolated from diseased Viburnum tinus and V. × bodnantense plants exhibiting symptoms of wilting and stem base discoloration. Subsequently, repeated surveys for P. ramorum were carried out in nurseries and areas surrounding nurseries throughout France. Since 2004, a large range of known hosts were investigated in approximately 2,000 nurseries and 200 other sites each year. P. ramorum was detected exclusively in nurseries at 29 locations in 2002, 9 in 2003, 23 in 2004, 17 in 2005, and 19 in 2006. Rhododendron spp. and occasionally V. tinus were the major hosts. In addition, the pathogen was detected for the first time on Pieris japonica in two nurseries in 2005 and on Camellia sp. in one nursery in 2006 from plants exhibiting leaf and twig blight. In both cases, P. ramorum had already been detected on Rhododendron spp. in the same nurseries. Most of the infected plants were found in northwestern France (Bretagne and Pays-de-la-Loire), or came from this region, which is the main rhododendron-growing area in France. In some cases, plants were imported from Belgium or the Netherlands. P. ramorum was also detected in a nursery in soil close to diseased Rhododendron spp. plants and pond water used for irrigation by using a combination of baiting with Rhododendron spp. leaves and PCR assay with species-specific primers (1). Overall, approximately 1% of the investigated nurseries were found positive each year, and this ratio was quite stable from 2004 to 2006. To date, P. ramorum has not been detected outside of nurseries, although many surveys were conducted on the west coast of France where the risk is considered to be high because of a favorable mild and humid climate and the presence of suitable hosts. In addition, 78 isolates of P. ramorum collected between 2002 and 2004 on Rhododendron spp. and V. tinus were found to be of A1 mating type based on pairings with P. cryptogea A1 and A2 mating types (2). References: (1) K. J. Hayden et al. Phytopathology 94:1075, 2004. (2) S. Werres and B. Zielke J. Plant Dis. Prot. 110:129, 2003. (3) S. Werres et al. Mycol. Res. 105:1155, 2001.

18.
Acta Biomater ; 41: 75-85, 2016 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-27286676

RESUMEN

UNLABELLED: Clinical success of bladder reconstructive procedures could be promoted by the availability of functional biomaterials. In this study, we have developed a multi-layered scaffold consisting of a bioactive fibrin layer laminated between two collagen sheets all having undergone plastic compression. With this construct we performed bladder augmentation in a nude rat model after partial bladder excision and evaluated the morphological and functional behavior of the implant. The fibrin was functionalized with a recombinant human insulin-like growth factor-1 (IGF-1) variant that covalently binds fibrin during polymerization and has a matrix metalloproteinase-cleavage insert to enable cell-mediated release. The purified IGF-1 variant showed similar bioactivity in vitro compared to commercially available wild type (wt) IGF-1, inducing receptor phosphorylation and induction of human smooth muscle cell proliferation. In vivo, the multi-layered bioactive collagen-fibrin scaffolds loaded with the IGF-1 variant triggered dose-dependent functional host smooth muscle cell invasion and bundle formation with re-urothelialization 4weeks after surgery in a rat model. STATEMENT OF SIGNIFICANCE: The design of new bio-functional scaffolds that can be employed for bladder reconstructive procedures is a growing focus in the field of tissue engineering. In this study, a fibrin binding form of human insulin-like growth factor-1 (IGF-1) was produced and used to functionalize a multi-layered collagen-fibrin scaffold consisting of bioactive fibrin layer, sandwiched between two collagen gels. An effective dosage of our IGF-1 variant was successfully determined via a nude rat bladder model, which may play a critical role in estimating its therapeutic dosage in clinical trials. Thus, this new bioactive scaffold may offer an advanced approach to accelerate bladder regeneration.


Asunto(s)
Colágeno/farmacología , Fibrina/farmacología , Factor I del Crecimiento Similar a la Insulina/farmacología , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Vejiga Urinaria/fisiología , Animales , Materiales Biocompatibles/farmacología , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Femenino , Humanos , Inmunohistoquímica , Miocitos del Músculo Liso/citología , Miocitos del Músculo Liso/efectos de los fármacos , Ratas Desnudas , Vejiga Urinaria/cirugía
19.
Biochim Biophys Acta ; 1315(1): 40-6, 1996 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-8611645

RESUMEN

The secondary structures of peptides beta 25-35 (the active toxic fragment) and beta 35-25 (reverse sequence and non-toxic fragment), as well as of the amidated beta (25-35)-NH2 peptide were investigated in aqueous solution and in the solid state by means of Fourier-transformed infrared spectroscopy and circular dichroism spectroscopy. The conformations of the beta 25-35 and beta 35-25 in solid state were identical and contained mostly beta-sheet structures. In solid state the amidated beta (25-35)-NH2 peptide also contained mostly beta-sheet structures. Freshly prepared aqueous solutions of the beta 25-32 (0.5 - 3.8 mM) contained a mixture of beta-sheet and random coil structures. Within 30-60 min incubation at 37 degrees C in water or in phosphate-buffered saline solution (PBS), beta 25-35 was almost fully converted to a beta-sheet structure. Decreasing the temperature from 37 degrees C to 20 degrees C decreased the rate of conversion from random coil to beta-sheet structures, 1-2 h being required for complete conversion. In contrast beta 35-25 in water or in PBS buffer had mostly a random coil structure and remained so for 6 days. The amidated beta(25-35)-NH2 peptide in water (2.7 mM) was also mostly random coil. However, when this peptide (2-2.7 mM) was dissolved in PBS (pH 7.4) or in 140 mM NaCl, a gel was formed and its conformation was mostly beta-sheet. Decreasing the concentration of beta (25-35)-NH2 peptide in 140 mM NaCl aqueous solution from 2 mM to 1 mM or below favored the conversion from beta-sheet structures to random coil structures. The beta 25-35 was toxic to PC12 cells while beta 35-25 was not. The amidated peptide beta (25-35)-NH2 was at least 500-fold less toxic than beta 25-35. Structural differences between these beta peptides in aqueous solutions may explain the difference in their respective toxicities.


Asunto(s)
Péptidos beta-Amiloides/química , Supervivencia Celular/efectos de los fármacos , Fragmentos de Péptidos/química , Estructura Secundaria de Proteína , Amidas/química , Amidas/toxicidad , Péptidos beta-Amiloides/toxicidad , Animales , Dicroismo Circular , Células PC12 , Fragmentos de Péptidos/toxicidad , Conformación Proteica , Ratas , Espectroscopía Infrarroja por Transformada de Fourier
20.
Curr Opin Chem Biol ; 1(3): 347-56, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9667872

RESUMEN

Spectroscopic and kinetic evidence for substrate-based radicals in the reactions of lysine 2,3-aminomutase and methane monooxygenase has recently been gathered. Evidence for a protein-based thiyl radical in the mechanism of the action of ribonucleotide reductase has been correlated with the proposed mechanism involving substrate-based radicals. Controversies have arisen about the mechanisms of ribonucleotide reductase and methane monooxygenase reactions.


Asunto(s)
Transferasas Intramoleculares/metabolismo , Oxigenasas/metabolismo , Ribonucleótido Reductasas/metabolismo , Compuestos de Sulfhidrilo/metabolismo , Cobamidas/metabolismo , Radicales Libres , Especificidad por Sustrato
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