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1.
Plant Mol Biol ; 114(1): 3, 2024 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-38217735

RESUMEN

Base excision repair (BER) generates gapped DNA intermediates containing a 5'-terminal 2-deoxyribose-5-phosphate (5'-dRP) group. In mammalian cells, gap filling and dRP removal are catalyzed by Pol ß, which belongs to the X family of DNA polymerases. In higher plants, the only member of the X family of DNA polymerases is Pol λ. Although it is generally believed that plant Pol λ participates in BER, there is limited experimental evidence for this hypothesis. Here we have characterized the biochemical properties of Arabidopsis thaliana Pol λ (AtPol λ) in a BER context, using a variety of DNA repair intermediates. We have found that AtPol λ performs gap filling inserting the correct nucleotide, and that the rate of nucleotide incorporation is higher in substrates containing a C in the template strand. Gap filling catalyzed by AtPol λ is most efficient with a phosphate at the 5'-end of the gap and is not inhibited by the presence of a 5'-dRP mimic. We also show that AtPol λ possesses an intrinsic dRP lyase activity that is reduced by mutations at two lysine residues in its 8-kDa domain, one of which is present in Pol λ exclusively and not in any Pol ß homolog. Importantly, we also found that the dRP lyase activity of AtPol λ allows efficient completion of uracil repair in a reconstituted short-patch BER reaction. These results suggest that AtPol λ plays an important role in plant BER.


Asunto(s)
Arabidopsis , ADN Polimerasa beta , Animales , Arabidopsis/genética , Arabidopsis/metabolismo , Reparación por Escisión , ADN Polimerasa Dirigida por ADN/genética , ADN Polimerasa Dirigida por ADN/química , ADN Polimerasa Dirigida por ADN/metabolismo , Reparación del ADN , Nucleótidos , Fosfatos , Mamíferos/metabolismo
2.
Transpl Int ; 36: 11331, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37680646

RESUMEN

The European Society of Organ Transplantation (ESOT) strives to promote equity, diversity, and inclusion (EDI) across all its activities. We surveyed the transplant community's experiences and perspectives regarding EDI within ESOT as an organization and its educational activities, and research in general. A total of 299 respondents completed the questionnaire. About half agreed that ESOT's Executive Committee, Council, and Sections/Committees are diverse and inclusive (51%) and that ESOT promotes EDI in its live and digital educational activities (54%). Forty percent of respondents agreed that scientific and clinical trials in the field of transplantation are diverse and inclusive. Despite the wide distribution of the survey, most of the respondents self-identified as White and were either physician or surgeon. However, the results contribute a unique insight into the experiences and perspectives of the transplantation community regarding EDI. Whilst ESOT is committed to the principles of EDI, perceptions and the high number of proposals show the apparent need to prioritize efforts to embed EDI across ESOT and transplantation science. These data should constitute a starting point for change and provide guidance for future efforts to promote EDI within the transplantation community.


Asunto(s)
Trasplante de Órganos , Cirujanos , Trasplantes , Humanos , Diversidad, Equidad e Inclusión
3.
Environ Res ; 204(Pt C): 112325, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34740618

RESUMEN

BACKGROUND: Limited evidence exists regarding transient neurobehavioral alterations associated with episodic pesticide exposures or agricultural pesticide spray periods. We previously observed that children examined soon after a pesticide spray period (the Mother's Day flower harvest [MDH]) had lower neurobehavioral performance than children examined later. The present study builds on our previous work by incorporating longitudinal analyses from childhood through adolescence. METHODS: We examined participants in agricultural communities in Ecuador (ESPINA study) during three periods: July-August 2008 (N = 313, 4-9-year-olds); April 2016 (N = 330, 11-17-year-olds); July-October 2016 (N = 535, 11-17-year-olds). Participants were examined primarily during a period of low floricultural production. Neurobehavior was assessed using the NEPSY-II (domains: Attention/Inhibitory Control, Language, Memory/Learning, Visuospatial Processing, and Social Perception). Linear regression and generalized linear mixed models were used to examine cross-sectional and longitudinal associations between examination date (days) after the MDH and neurobehavioral outcomes, adjusting for demographic, anthropometric, and socio-economic variables. RESULTS: Participants were examined between 63 and 171 days after the MDH. Mean neurobehavioral domain scores ranged from 1.0 to 17.0 (SDrange = 2.1-3.1) in 2008 and 1.0 to 15.5 (SDrange = 2.0-2.3) in 2016. In cross-sectional analyses (2016 only; N = 523), we found significant or borderline positive associations between time after the MDH and Attention/Inhibitory Control (difference/10 days [ß] = 0.22 points [95% CI = 0.03, 0.41]) and Language (ß = 0.16 points [95% CI = -0.03, 0.34]). We also observed positive, longitudinal associations (2008-2016) with Attention/Inhibitory Control (ß = 0.19 points [95% CI = 0.04, 0.34]) through 112 days after the harvest and Visuospatial Processing (ß = 3.56, ß-quadratic = -0.19 [95% CI: -0.29, -0.09]) through 92 days. CONCLUSIONS: Children examined sooner after the harvest had lower neurobehavioral performance compared to children examined later, suggesting that peak pesticide spray seasons may transiently affect neurobehavior followed by recovery during low pesticide-use periods. Reduction of pesticide exposure potential for children during peak pesticide-use periods is advised.


Asunto(s)
Plaguicidas , Adolescente , Niño , Estudios Transversales , Ecuador/epidemiología , Exposición a Riesgos Ambientales , Humanos , Pruebas Neuropsicológicas
4.
Lett Appl Microbiol ; 70(3): 203-209, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31837237

RESUMEN

Ready-to-eat food contamination with ESBL-producing Escherichia coli is a growing health concern. Some of these strains also are epidemic clones and can cause community-associated infections that are difficult to treat. In this study, the occurrence of ESBL-producing E. coli contaminated ready-to-eat street food in Quito, Ecuador was evaluated. In total, 150 samples were collected randomly in the most crowded sites of the city. In all, 34 samples (34/150; 22·6%) were positive for total thermotolerant (44·5°C) coliforms resistant to cefotaxime. MALDI-TOF analysis identified that the E. coli was found in 20 food samples (20/34; 59%). ESBL gene blaCTX-M-55 was identified in nine isolates, blaCTX-M-15 in six isolates, blaCTX-M-14 in two isolates, and one isolate each harboured blaCTX-M-24 , blaCTX-M-65 , blaCTX-M-55 and blaCTX-M-8 . Phylogenetic groups like A and B1 were the most common, followed by groups D and B2. MLST analysis identified 12 different sequence types (STs), the most common was ST162. Recognized epidemic clonal groups ST410, ST131 and ST744 were encountered. Ready-to-eat street food is a potential way of spreading ESBL-producing E. coli epidemic clones in Quito, Ecuador. SIGNIFICANCE AND IMPACT OF THE STUDY: This study identified ESBL-producing Escherichia coli epidemic clones: ST131, ST410 and ST744 in ready-to-eat street food samples. Street food is a possible way to spread harm multidrug-resistant (MDR) E. coli strains in the community. Studies to identify the contamination sources of this kind of food are needed to tackle MDR E. coli dissemination.


Asunto(s)
Farmacorresistencia Bacteriana Múltiple/genética , Infecciones por Escherichia coli/transmisión , Escherichia coli/efectos de los fármacos , Escherichia coli/genética , Comida Rápida/microbiología , beta-Lactamasas/genética , Antibacterianos/farmacología , Ecuador/epidemiología , Infecciones por Escherichia coli/epidemiología , Contaminación de Alimentos/análisis , Humanos , Tipificación de Secuencias Multilocus , Filogenia
5.
Mol Psychiatry ; 23(5): 1233-1243, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-28322273

RESUMEN

Numerous genetic and functional studies implicate variants of Neuregulin-1 (NRG1) and its neuronal receptor ErbB4 in schizophrenia and many of its endophenotypes. Although the neurophysiological and behavioral phenotypes of NRG1 mutant mice have been investigated extensively, practically nothing is known about the function of NRG2, the closest NRG1 homolog. We found that NRG2 expression in the adult rodent brain does not overlap with NRG1 and is more extensive than originally reported, including expression in the striatum and medial prefrontal cortex (mPFC), and therefore generated NRG2 knockout mice (KO) to study its function. NRG2 KOs have higher extracellular dopamine levels in the dorsal striatum but lower levels in the mPFC; a pattern with similarities to dopamine dysbalance in schizophrenia. Like ErbB4 KO mice, NRG2 KOs performed abnormally in a battery of behavioral tasks relevant to psychiatric disorders. NRG2 KOs exhibit hyperactivity in a novelty-induced open field, deficits in prepulse inhibition, hypersensitivity to amphetamine, antisocial behaviors, reduced anxiety-like behavior in the elevated plus maze and deficits in the T-maze alteration reward test-a task dependent on hippocampal and mPFC function. Acute administration of clozapine rapidly increased extracellular dopamine levels in the mPFC and improved alternation T-maze performance. Similar to mice treated chronically with N-methyl-d-aspartate receptor (NMDAR) antagonists, we demonstrate that NMDAR synaptic currents in NRG2 KOs are augmented at hippocampal glutamatergic synapses and are more sensitive to ifenprodil, indicating an increased contribution of GluN2B-containing NMDARs. Our findings reveal a novel role for NRG2 in the modulation of behaviors with relevance to psychiatric disorders.


Asunto(s)
Dopamina/metabolismo , Trastornos Mentales/metabolismo , Factores de Crecimiento Nervioso/deficiencia , Animales , Conducta Animal/fisiología , Encéfalo/metabolismo , Clozapina/farmacología , Dopamina/genética , Receptores ErbB/metabolismo , Masculino , Trastornos Mentales/genética , Ratones , Ratones Noqueados , Factores de Crecimiento Nervioso/genética , Factores de Crecimiento Nervioso/metabolismo , Neurregulina-1/genética , Neurregulina-1/metabolismo , Receptor ErbB-4/genética , Receptor ErbB-4/metabolismo , Transducción de Señal , Sinapsis/metabolismo , Transcriptoma
6.
Bull Entomol Res ; 108(5): 694-704, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29198200

RESUMEN

Natural control by predators and parasitoids provides an important and often unnoticed ecosystem service to agricultural landscapes by reducing pest populations in crops. The current model of horticultural intensification in south-eastern Spain produces high yields but has also resulted in a landscape almost completely covered by plastic. Promoting natural areas among greenhouses could enhance biodiversity, by being beneficial insects, and reduce pest pressure outdoors. The first step is to ascertain how pests and their natural enemies (NEs) use Mediterranean vegetation for selecting the best plants for pest suppression outdoors. The abundance of the two major horticultural pests, the tobacco whitefly, Bemisia tabaci, and the western flower thrips, Frankliniella occidentalis, together with their NEs, were assayed in 22 flowering perennial plants, which were newly planted in an experimental field surrounded by greenhouses. Eight plant species were identified as the most critical species for sustaining pest populations outdoors. A set of five plant species supported a medium level of pests, and another set of ten plant species supported the lowest level of both pests. Tobacco whitefly occurred in a few plants species, whereas western flower thrips occurred on almost all the plant species studied, and was favoured by the presence of flowers in perennial plants. The results suggest that plant diversity may provide relatively few acceptable host plants for tobacco whitefly than for western flower thrips. NEs were generally collected in plants that also supported abundance of pests, indicating that host/prey availability, more than food resources from flowers, was a stronger predictor of NE abundance in perennial plants. Field trials using the plants with the lowest host acceptance by pests are needed in order to ascertain whether pest abundance outdoors is reduced.


Asunto(s)
Hemípteros , Control Biológico de Vectores/métodos , Thysanoptera , Animales , Biodiversidad , Control de Insectos/métodos , España
7.
Public Health ; 147: 39-46, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28404494

RESUMEN

OBJECTIVES: Chile is a post-transitional country evolving towards a stationary population pyramid, which may be associated with increasing preterm birth (PTB) rates. This study aimed to compare maternal sociodemographic characteristics between the start of the post-transition phase (1994) and an established stage (2013) and to evaluate associations between these characteristics and PTB. STUDY DESIGN: An observational analytic design was conducted using national birth records (n = 4,956,311). METHODS: Variables analysed in the 20 birth cohorts from 1994 to 2013 were: length of gestation (preterm <37 weeks) subdivided by gestational age (extreme, moderate/severe and late); maternal age (≤19, 20-35 and >35 years); education level (<8, 8-12 and >12 years of education); employment; marital status; area of residence; and type of birth (singleton, twins, and triplets or higher order). The prevalence of PTB was expressed as a percentage, and associations between PTB and predictor variables were analysed using logistic regression models. RESULTS: Education level, age >35 years, maternal employment, unmarried status, twin delivery and urban residency rates increased between 1994 and 2013. According to the adjusted models, age >35 years and delivery of more than two foetuses were risk factors for all PTB subtypes. Maternal employment was a risk factor for moderate/severe, late and total PTB, and a low level of education was a risk factor for late and total PTB. On the other hand, age ≤19 years was protective against all PTB subtypes. CONCLUSIONS: All maternal characteristics changed between 1994 and 2013. Furthermore, the prevalence of PTB increased for all predictor variables studied over this period.


Asunto(s)
Madres/estadística & datos numéricos , Nacimiento Prematuro/epidemiología , Adolescente , Adulto , Chile/epidemiología , Estudios de Cohortes , Países en Desarrollo , Femenino , Humanos , Recién Nacido , Embarazo , Prevalencia , Factores de Riesgo , Factores Socioeconómicos , Adulto Joven
8.
Epidemiol Infect ; 144(14): 2967-2970, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27586373

RESUMEN

Colistin resistance mediated by the mcr-1 gene has been reported worldwide, but to date not from the Andean region, South America. We report the first clinical isolate of Escherichia coli harbouring the mcr-1 gene in Ecuador. The strain was isolated from peritoneal fluid from a 14-year-old male with acute appendicitis, and subjected to molecular analysis. The minimum inhibitory concentration of colistin for the strain was 8 mg/ml and it was susceptible to carbapenems but resistant to tigecycline. The strain harboured mcr-1 and bla CTX-M-55 genes and was of sequence type 609. The recognition of an apparently commensal strain of E. coli harbouring mcr-1 serves as an alert to the presence in the region of this recently described resistance mechanism to one of the last line of drugs available for the treatment of multi-resistant Gram-negative infections.


Asunto(s)
Antibacterianos/farmacología , Colistina/farmacología , Farmacorresistencia Bacteriana , Proteínas de Escherichia coli/genética , Escherichia coli/fisiología , Enfermedad Aguda , Adolescente , Apendicitis/microbiología , Ecuador , Escherichia coli/genética , Infecciones por Escherichia coli/microbiología , Humanos , Masculino , Pruebas de Sensibilidad Microbiana
9.
Am J Transplant ; 15(3): 764-71, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25655040

RESUMEN

It has been suggested that vascular stasis during cardio-circulatory arrest leads to the formation of microvascular thrombi and the viability of organs arising from donation after circulatory determination of death (DCDD) donors may be improved through the application of fibrinolytic therapy. Our aim was to comprehensively study the coagulation profiles of Maastricht category II DCDD donors in order to determine the presence of coagulation abnormalities that could benefit from fibrinolytic therapy. Whole blood from potential DCDD donors suffering out-of-hospital cardiac arrest was sampled after declaration of death in the emergency department, and rotational thromboelastomeric analysis was performed. Between July 2012 and December 2013, samples from 33 potential DCDD donors were analyzed. All patients demonstrated hyperfibrinolysis (HF), as reflected by maximum clot lysis of 98-100% in all cases, indicating that there is no role for additional fibrinolytic therapy in this setting. As well, we observed correlations between thromboelastomeric lysis parameters and maximum hepatic transaminase levels measured in potential donors and renal artery flows measured during ex situ hypothermic oxygenated machine perfusion, indicating that further studies on the utility of thromboelastometry to evaluate organ injury and perhaps even viability in unexpected DCDD may be warranted.


Asunto(s)
Coagulación Sanguínea , Fibrinólisis , Trasplante de Órganos , Donantes de Tejidos , Circulación Sanguínea , Femenino , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
10.
Clin Transplant ; 28(10): 1155-66, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25109314

RESUMEN

In the recent years, more than 60% of available deceased donors are either older than 50 yr or have significant vascular comorbidities. This makes the acceptance and rejection criteria of renal allografts very rigorous, especially in cases of younger recipients, and at the same time encourages live donations. In our country, there is a lack of homogeneity in the percentages of use of expanded criteria donor (ECD) allografts between the different autonomous communities. Furthermore, the criteria vary greatly, and in some cases, great importance is given to the biopsy while in others very little. In this study, we present a unified and homogenous criteria agreed upon by consensus of a 10-member Panel representing major scientific societies related to renal transplantation in Spain. The criteria are to be used in accepting and/or rejecting kidneys from the so-called ECDs. The goal was to standardize the use of these organs, to optimize the results, and most importantly to provide for the maximum well being of our patients. Finally, we believe that after taking into account the Panel's thorough review of specific scientific literature, this document will be adaptable to other national renal transplant programmes.


Asunto(s)
Fallo Renal Crónico/cirugía , Trasplante de Riñón/normas , Selección de Paciente , Donantes de Tejidos , Obtención de Tejidos y Órganos/métodos , Consenso , Supervivencia de Injerto , Humanos , Registros Médicos , Persona de Mediana Edad , Pronóstico , España , Listas de Espera
11.
Am J Transplant ; 12(1): 162-70, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22070538

RESUMEN

Maastricht type 2 donation after cardiac death (DCD) donors suffer sudden and unexpected cardiac arrest, typically outside the hospital; they have significant potential to expand the donor pool. Herein, we analyze the results of transplanted livers and all potential donors treated under our type 2 DCD protocol. Cardiac arrest was witnessed; potential donors arrived at the hospital after attempts at resuscitation had failed. Death was declared based on the absence of cardiorespiratory activity during a 5-min no-touch period. Femoral vessels were cannulated to establish normothermic extracorporeal membrane oxygenation, which was maintained until organ recovery. From April 2002 to December 2010, there were 400 potential donors; 34 liver transplants were performed (9%). Among recipients, median age, model for end-stage liver disease and cold and reperfusion warm ischemic times were 55 years (49-60), 19 (14-21) and 380 (325-430) and 30 min (26-35), respectively. Overall, 236 (59%) and 130 (32%) livers were turned down due to absolute and relative contraindications to donate, respectively. One-year recipient and graft survivals were 82% and 70%, respectively (median follow-up 24 months). The applicability of type 2 DCD liver transplant was <10%; however, with better preservation technology and expanded transplant criteria, we may be able to improve this figure significantly.


Asunto(s)
Muerte , Trasplante de Hígado , Donantes de Tejidos , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad
12.
Avian Dis ; 54(4): 1306-9, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21313855

RESUMEN

Histologic findings in chickens experimentally infected by nasal instillation with reference strains of Gallibacterium anatis are described. No clinical signs were observed in experimentally infected birds; however, sequential histologic examinations of trachea, lung, air sacs, and liver revealed lesions in all infected chickens. Our observations suggest that the reference strains of G. anatis used in this experiment are capable of causing primary infection in chickens. Despite that the experimental birds were inoculated by intranasal route, lesions were detected in the liver, suggesting a probable bacteremia. Because several degrees of severity were established in histopathologic lesions, probable variations in virulence, among the experimental strains, also are discussed.


Asunto(s)
Pollos , Infecciones por Pasteurellaceae/veterinaria , Pasteurellaceae/clasificación , Sacos Aéreos/patología , Animales , Hígado/patología , Pulmón/patología , Infecciones por Pasteurellaceae/patología , Organismos Libres de Patógenos Específicos
13.
Nefrologia ; 30(1): 54-63, 2010.
Artículo en Español | MEDLINE | ID: mdl-20038970

RESUMEN

INTRODUCTION: During the last years the number of patients on waiting list for kidney transplantation has been stable. Living donor kidney transplantation is nowadays a chance to increase the pool of donors. However, there are a group of patients with ABO incompatibility, making impossible the transplant until now. The aim of the present study is to describe the experience of Hospital Clinic Barcelona on ABO incompatible living transplantation. METHODS: A retrospective- descriptive study was made based on 11 living donor kidney recipients with ABO incompatibility in Hospital Clinic of Barcelona from October'06 to January'09. Selective blood group, antibody removal with specific immunoadsortion, immunoglobulin and anti- CD 20 antibody were made until the immunoglobulin (IgG) and isoaglutinine (IgM) antibody titters were 1/8 or lower. Immunosuppressive protocol was adjusted to particular recipient characteristics. Isoaglutinine titters were set before, during and post desensitization treatment and two weeks after transplant. Immunological, medical and surgical evaluation was the standard in living donor kidney transplant program. RESULTS: Medium age of donors and recipients were 47.8 +/- 12.4 and 44.4 +/- 14.1 years, respectively. 90% of donors were females and 73% of recipients males. Follow-up time was 10.2 +/- 10.2 months. Siblings and spouses were the most frequent relation (n=4, 36.4%, respectively). Chronic glomerulonephritis, adult polycystic kidney disease and Alport syndrome, the most frequent cause of end-stage renal disease. All the patients acquire appropriate isoaglutinine titters pre transplant (< 1/8), requiring 5.54 +/- 2.6 immunoadsorption sessions pretransplant and 2.82 posttransplant. One patient didn t need any immunoadsorption session (incompatibility blood group B) and another patient plasma exchange instead of immunoadsorption for being hypersensitized with positive flow cytometry crossmatch. Posttransplant isoaglutinine titters remained low. Two patients had cellular acute rejection episode (type IA and IB of Banff classification) with good response to corticosteroid treatment. Patient and graft survival were 91% at first year and remain stable during the follow-up. A graft lost by death of patient in relation to haemorrhagic shock developed within the first 72 hours after transplantation. Renal graft function at first year was excellent with serum creatinine of 1.3 +/- 0.8 mg/dl, creatinine clearance of 62.6 ml/min/1.73 m2 and proteinuria of 244.9 mg/U-24h. CONCLUSION: ABO incompatible living donor kidney transplantation represent an effective and safe alternative in certain patients on waiting list for renal transplant, obtaining excellent results in patient and graft survival, with good renal graft function.


Asunto(s)
Sistema del Grupo Sanguíneo ABO/inmunología , Incompatibilidad de Grupos Sanguíneos , Trasplante de Riñón/inmunología , Donadores Vivos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
14.
Sci Rep ; 10(1): 8961, 2020 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-32488099

RESUMEN

We have theoretically investigated the electronic states in a core/shell pyramidal quantum dot with GaAs core embedded in AlGaAs matrix. This system has a quite similar recent experimental realization through a cone/shell structure [Phys. Status Solidi-RRL 13, 1800245 (2018)]. The research has been performed within the effective mass approximation taking into account position-dependent effective masses and the presence of external electric and magnetic fields. For the numerical solution of the resulting three-dimensional partial differential equation we have used a finite element method. A detailed study of the conduction band states wave functions and their associated energy levels is presented, with the analysis of the effect of the geometry and the external probes. The calculation of the non-permanent electric polarization via the off-diagonal intraband dipole moment matrix elements allows to consider the related optical response by evaluating the coefficients of light absorption and relative refractive index changes, under different applied magnetic field configurations.

15.
Neurobiol Learn Mem ; 92(3): 267-82, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18809505

RESUMEN

Delay classical eyeblink conditioning (EBC) is an important model of associative, cerebellar-dependent learning. Norepinephrine (NE) plays a significant modulatory role in the acquisition of learning; however, other neurotransmitters are also involved. The goal was to determine whether NE, gamma-aminobutyric acid (GABA) and glutamate (GLU) release are observed in cerebellar cortex during EBC, and whether such release was selectively associated with training. Further studies examined the role of the beta-noradrenergic receptor in consolidation of the learned response by local infusion of propranolol at 5-120 min following training into the cerebellar cortex. In vivo microdialysis coupled to EBC was performed to examine neurotransmitter release. An increase in the extracellular level of NE was observed during EBC and was maximal on day 1 and diminished in amplitude with subsequent days of training. No changes in baseline NE release were observed in pseudoconditioning indicating that NE release is directly related to the associative learning process. The extracellular levels of GABA were also increased selectively during paired training however, the magnitude of GABA release increased over days of training. GLU release was observed to increase during both paired and unpaired training, suggesting that learning does not occur prior to the information arriving in the cerebellum. When propranolol was administered at either 5-, 60-, or 120-min post-training, there was an inhibition of conditioned responses, these data support the hypothesis that NE is important for consolidation of learning. In another set of experiments we demonstrate that the timing of release of NE, GABA and glutamate are significantly delayed in onset and lengthened in duration in the 22-month-old F344 rats. Over days of training the timing of release becomes closer to the timing of training and this is associated with increased learning of conditioned responses in the aged rats.


Asunto(s)
Envejecimiento/fisiología , Aprendizaje por Asociación/fisiología , Cerebelo/fisiología , Condicionamiento Palpebral/fisiología , Memoria/fisiología , Neurotransmisores/metabolismo , Antagonistas Adrenérgicos beta/farmacología , Animales , Cerebelo/efectos de los fármacos , Condicionamiento Palpebral/efectos de los fármacos , Espacio Extracelular/metabolismo , Ácido Glutámico/metabolismo , Masculino , Norepinefrina/metabolismo , Propranolol/farmacología , Ratas , Ratas Endogámicas F344 , Receptores Adrenérgicos beta/metabolismo , Factores de Tiempo , Ácido gamma-Aminobutírico/metabolismo
16.
Transplant Proc ; 51(2): 365-368, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30879542

RESUMEN

The strict selection of pancreas for transplant has forced the development of different documents to select the suitable organ in order to minimize the risks and complications of the transplant. In 2008, Eurotransplant published the Preprocurement Pancreas Allocation Suitability Score (P-PASS) for pretransplant selection. In 2001 the Hospital Clinic of Barcelona developed a Clinical Consensus Document (CCD). OBJECTIVES: We aimed to analyze the predictive decision of the pancreas acceptance to offers received in the hospital, according to the CCD criteria and compare it with the recommended value of suitability for accepting the pancreas according to the P-PASS value. MATERIAL AND METHODS: We performed a retrospective comparative study between the criteria of selection of the CCD for pancreas from 2016-2017 in comparison with the values obtained if the P-PASS had been used: ≤ 17, acceptance criteria and P-PASS; > 17, risk criteria. We defined the organ reported as rejected or accepted. The accepted organ could be procured and transplanted or discarded. RESULTS: With the CCD criteria, 7 more organs were transplanted than if we only applied the potential P-PASS criteria. In contrast, P-PASS would have ruled out an additional 9% of pancreases in relation to CCD criteria. CONCLUSIONS: According our experience, it is difficult to find an adequate prediction model to select pancreas for transplantation. The application of the DCC criteria increases the number of organs valid for transplantation. At present, new criteria should be re-evaluated within multicenter studies.


Asunto(s)
Trasplante de Páncreas/métodos , Donantes de Tejidos/provisión & distribución , Obtención de Tejidos y Órganos/métodos , Adulto , Supervivencia de Injerto , Humanos , Persona de Mediana Edad , Guías de Práctica Clínica como Asunto , Estudios Retrospectivos
17.
Int J Tuberc Lung Dis ; 23(2): 166-173, 2019 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-30808448

RESUMEN

BACKGROUND: The genetic diversity of Mycobacterium tuberculosis in Quito, Ecuador is not well known. OBJECTIVE: To investigate mutations related to drug resistance and bacterial genotypes in M. tuberculosis strains in Ecuador. DESIGN: This was a retrospective study of M. tuberculosis isolates from 104 patients. Isolates were phenotypically resistant to rifampicin (RMP) and/or isoniazid (INH). The genotype was determined using 24-locus mycobacterial interspersed repetitive units-variable-number tandem repeats (MIRU-VNTR). RESULTS: Isolates showed mutations in the rpoB and katG genes, and the inhA promoter. In rpoB, we found 13 genetic alterations at codons 511, 513, 514, 515, 516, 526 and 531. Forty-six (44.2%) RMP-resistant isolates belonged to codon 531. In katG, there were nine genetic alterations at codons 296, 312, 314, 315, 322, 324 and 351. Fifty-three (51%) INH-resistant isolates belonged to codon 315. Five mutations not previously described were identified in katG: Thr324Ser, Thr314Ala, Ala312Pro, Trp351Stop and deleted G at 296 codon. The Latin American Mediterranean (LAM) (33.7%) and Ghana (30.8%) lineages presented most of the main mutations observed. CONCLUSION: This is the first report from Ecuador; it describes five new mutations in katG and indicates that LAM is the most prevalent lineage.


Asunto(s)
Antituberculosos/farmacología , Variación Genética , Mycobacterium tuberculosis/aislamiento & purificación , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico , Farmacorresistencia Bacteriana/genética , Ecuador , Genotipo , Humanos , Isoniazida/farmacología , Repeticiones de Minisatélite/genética , Mutación , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/genética , Fenotipo , Estudios Retrospectivos , Rifampin/farmacología , Tuberculosis Resistente a Múltiples Medicamentos/epidemiología , Tuberculosis Resistente a Múltiples Medicamentos/microbiología
18.
Open Forum Infect Dis ; 6(6): ofz180, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31198815

RESUMEN

BACKGROUND: We analyzed the prevalence, etiology, and risk factors of culture-positive preservation fluid and their impact on the management of solid organ transplant recipients. METHODS: From July 2015 to March 2017, 622 episodes of adult solid organ transplants at 7 university hospitals in Spain were prospectively included in the study. RESULTS: The prevalence of culture-positive preservation fluid was 62.5% (389/622). Nevertheless, in only 25.2% (98/389) of the cases were the isolates considered "high risk" for pathogenicity. After applying a multivariate regression analysis, advanced donor age was the main associated factor for having culture-positive preservation fluid for high-risk microorganisms. Preemptive antibiotic therapy was given to 19.8% (77/389) of the cases. The incidence rate of preservation fluid-related infection was 1.3% (5 recipients); none of these patients had received preemptive therapy. Solid organ transplant (SOT) recipients with high-risk culture-positive preservation fluid receiving preemptive antibiotic therapy presented both a lower cumulative incidence of infection and a lower rate of acute rejection and graft loss compared with those who did not have high-risk culture-positive preservation fluid. After adjusting for age, sex, type of transplant, and prior graft rejection, preemptive antibiotic therapy remained a significant protective factor for 90-day infection. CONCLUSIONS: The routine culture of preservation fluid may be considered a tool that provides information about the contamination of the transplanted organ. Preemptive therapy for SOT recipients with high-risk culture-positive preservation fluid may be useful to avoid preservation fluid-related infections and improve the outcomes of infection, graft loss, and graft rejection in transplant patients.

19.
J Chromatogr B Analyt Technol Biomed Life Sci ; 1081-1082: 51-57, 2018 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-29502029

RESUMEN

A highly sensitive method was developed to measure putrescine by micellar electrokinetic chromatography with laser induced fluorescence detection with excellent linearity in the 1 nM to 3 µM range. The technique was tested on a drop of blood from Parkinson's disease patients obtained by finger prick. The results showed a statistically significant increase of putrescine in the erythrocytes compared to controls and a non-significant increase in plasma. This high level of putrescine does not constitute by itself proof that putrescine and polyamines are directly related to Parkinson's disease. However, the present results and several others addressed in the discussion suggest that these compounds might be causally involved in the pathophysiology of Parkinson's disease. In addition, the analytical method reported here may help to find new biomarkers for many diseases including Parkinson's disease.


Asunto(s)
Cromatografía Capilar Electrocinética Micelar/métodos , Eritrocitos/química , Enfermedad de Parkinson/sangre , Putrescina/sangre , Espectrometría de Fluorescencia/métodos , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Humanos , Límite de Detección , Modelos Lineales , Persona de Mediana Edad , Reproducibilidad de los Resultados
20.
Brain Res ; 1141: 56-64, 2007 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-17292337

RESUMEN

It has been shown using in vitro techniques that BDNF and NGF evoke neurotransmitter release in the hippocampus but this phenomenon has not been demonstrated in vivo to date. We therefore performed in vivo microdialysis in urethane-anesthetized Fischer 344 rats. The microdialysis probe was implanted stereotaxically into the CA1 area of the hippocampus. Three hours after the implantation of the probe, glutamate (Glu) and dopamine (DA) levels had reached a stable baseline. Four baseline samples were collected every 15 min at a flow rate of 1 microL/min. The growth factors were delivered (1 microL/10 min) using a microinjector attached to the microdialysis probe. We found that BDNF and NGF, when administered into the hippocampus, evoked dopamine and glutamate release in a dose-dependent fashion. NGF produced a biphasic response in the release of Glu, and a uniphasic response in the release of DA, both of which were calcium dependent. The neurotransmitter release induced by NGF was blocked by tetrodotoxin, indicating neuronal origin of this response. The BDNF induced release of DA and Glu was decreased in low calcium conditions, indicating that it is at least partially calcium dependent. Furthermore, BDNF-induced neurotransmitter release was partially blocked by pre-treatment with K252a, an antagonist for tyrosine kinase receptors, indicating that BDNF is acting through Trk receptors to induce neurotransmitter release. These results demonstrate a close relationship between the growth factors BDNF and NGF and the neurotransmitters DA and Glu in the hippocampus of intact animals.


Asunto(s)
Factor Neurotrófico Derivado del Encéfalo/farmacología , Dopamina/metabolismo , Ácido Glutámico/metabolismo , Hipocampo/efectos de los fármacos , Factor de Crecimiento Nervioso/farmacología , Animales , Área Bajo la Curva , Carbazoles/farmacología , Cromatografía Líquida de Alta Presión/métodos , Interacciones Farmacológicas , Electroquímica/métodos , Inhibidores Enzimáticos/farmacología , Alcaloides Indólicos/farmacología , Masculino , Microdiálisis , Ratas , Ratas Endogámicas F344
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