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ntroducción: Las infecciones de piel y partes blandas (IPPB) constituyen la tercera causa de consulta en nuestro centro. S.aureus es el agente etiológico más frecuente en este tipo de infecciones y la meticilino resistencia es clínicamente el mecanismo de resistencia más importante. El objetivo de este trabajo fue analizar la prevalencia de los distintos agentes etiológicos en IPPB en pacientes ambulatorios, así como también estudiar su sensibilidad a los antibióticos y resistencias acompañantes más frecuentes. Materiales y métodos: Estudio descriptivo y retrospectivo que incluyó todas las muestras provenientes de IPPB de pacientes ambulatorios desde octubre de 2017 a abril de 2022. Resultados: Se obtuvieron 180 cultivos positivos de muestras provenientes de IPPB durante el periodo estudiado, 12 fueron infecciones polimicrobianas. En total se obtuvieron 307 aislamientos: el microorganismo aislado con mayor frecuencia fue S.aureus (111; 36,2%). Se hallaron 71 SAMR (64%) y 40 SAMS (36%). De los SAMR, 67 (95%) fueron comunitarios (SAMRC) por criterios microbiológicos, y 4 SAMR hospitalarios (5%). De las cepas SAMRC, 44 (66%) no presentaron resistencias acompañantes, 15 (22% ) fueron resistentes a eritromicina, 12 (18%) a gentamicina y 7 (10%) a clindamicina. Conclusiones: El microorganismo más frecuentemente aislado en IPPB en pacientes ambulatorios fue el S.aureus y 67 aislamientos fueron categorizados como SAMRC por lo cual es necesario considerar al SAMRC como un patógeno frecuente. Debido a la baja resistencia hallada para CLI y TMS ambos podrían ser de elección en el tratamiento empírico en las IPPB en pacientes ambulatorios
Background:S. aureus is the main cause of skin and soft tissues infections (SSTIs) in immunocompetent patients. This type of infection is the third cause of medical consultation in our center. Our objective was to evaluate the prevalence of S. aureus, as well as its sensitivity to antimicrobials, isolated from skin and soft tissue samples from outpatients at an interzonal general acute care hospital located in Buenos Aires, Argentina.Methods: Descriptive and retrospective study that included all outpatient SSTIs samples from October 2017 to April 2022.Results: We obtained 215 positive cultures of samples from SSTIs during the study period. Of a total of 276 isolates: the most frequently isolated microorganism wasS. aureus (111; 40.22%). The prevalence of S. aureuswas 51.63%. We found 71 MRSA (63.96%). Of the SAMR strains, 60.56% did not present accompanying resistance, and only 8 isolates (11.27%) showed resistance to clindamycin. All SAMRs remained sensitive to minocycline and trimethoprim-sulfamethoxazole.Conclusions: The most frequently isolated microorganism in SSTIs was S. aureus and 71 isolates were categorized as SAMR, therefore it is necessary to consider SAMR as a frequent pathogen. Due to the low resistance found for CLI and TMS, they should be considered for empirical treatment in SSTIs in outpatients
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Humanos , Masculino , Femenino , Pacientes Ambulatorios , Infecciones Estafilocócicas/inmunología , Prevalencia , Manejo de EspecímenesRESUMEN
Tetracyclines are antibiotics considered emerging pollutants and currently, wastewater treatment plants are not able to remove them efficiently. Laccases are promising enzymes for bioremediation because they can oxidize a wide variety of substrates. The aim of this study was to evaluate the Botrytis aclada laccase for the oxidation of chlortetracycline and its isomers in the absence of a mediator molecule, at a pH range between 3.0 to 7.0, and to characterize the transformation products by LC-MS. Chlortetracycline and three isomers were detected in both, controls and reaction mixtures at 0 h and in controls after 48 h of incubation but in different proportions depending on pH. An additional isomer was also detected, but only in the presence of BaLac. Based on the transformation products identified in the enzymatic reactions and information from literature, we assembled a network of transformation pathways starting from chlortetracycline and its isomers. The spectrometric analysis of the products indicated the probable occurrence of oxygen insertion, dehydrogenation, demethylation and deamination reactions. Four new products were identified, and we also described a novel transformation product without the chloro group. We observed that increasing pH led to higher diversity of main products. This is the first study using the laccase from fungi Botrytis aclada to oxidate chlortetracycline and its isomers and it can be considered as an ecological alternative to be used in bioremediation processes such as wastewater.
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Botrytis , Clortetraciclina , Cromatografía Líquida con Espectrometría de Masas , Lacasa/química , Lacasa/metabolismo , Cromatografía Liquida , Espectrometría de Masas en Tándem , Concentración de Iones de Hidrógeno , Oxidación-ReducciónRESUMEN
BACKGROUND: Frailty is a key element in healthy ageing in which muscle performance plays a main role. Beta-hydroxy-beta-methylbutyrate (HMB) supplementation has shown favourable effects in modulating protein synthesis, improving muscle mass and function in interventional studies. Decreased age-related endogenous HMB levels have been shown in previous studies. The aim of the present study is to assess whether there is an association between endogenous plasma HMB levels and frailty. METHODS: Data from 1290 subjects (56.98% women; mean ± standard deviation age 74.6 ± 5.95 years) from the Toledo Study for Healthy Aging were obtained. Participants had their frailty status qualified according to Fried's Frailty Phenotype (FFP) score and the Frailty Trait Scale in its 12-domain version (FTS-12). Plasma HMB levels were analysed by an ultrahigh-performance liquid chromatography tandem mass spectrometry. Differences between groups (frail vs. non-frail) were tested using Mann-Whitney U test, Kruskal-Wallis test and chi-squared test. The association between HMB and frailty was assessed by multivariate linear and logistic regressions when frailty was analysed as continuous and binary, respectively. Models were adjusted by age, gender, comorbidity, body composition and protein intake. RESULTS: HMB levels were lower in those aged ≥75 years than in those aged 65-74 years, with an inverse linear relationship between age and HMB levels (ß = -0.031; P = 0.018), mainly accounted by males (ß = -0.062; P = 0.002). HMB levels were higher in men (0.238 ± 0.065 vs. 0.193 ± 0.051 ng/mL; P ≤ 0.001). HMB levels were significantly lower in frail than in non-frail individuals: 0.204 ± 0.058 versus 0.217 ± 0.063 ng/dL (P = 0.001) according to the FFP and 0.203 ± 0.059 versus 0.219 ± 0.063 ng/mL (P < 0.001) according to FTS-12. These differences showed a dose-dependent profile when we compared them by quintiles of HMB (P for trend: 0.022; 0.012 and 0.0004, respectively, for FFP, FTS-12 binary and FTS-12 continuous). Variables associated with low HMB levels were body mass index, strength, exhaustion and weight loss. Frailty was associated with HMB levels in all the adjusted models, including the fully adjusted ones, no matter the tool used (odds ratio: 0.45 [0.26, 0.77] for FFP and 0.36 [0.20, 0.63] for FTS-12 binary; ß = -4.76 [-7.29, -2.23] for FTS-12 score). This association was also observed when the analyses were done by quintiles, showing such association since Q4 (FFP), Q2 (FTS-12 binary) and Q3 (FTS-12 score). The associations were observed in the whole sample and in each gender. CONCLUSIONS: There is an inverse association between HMB levels and frailty status. These findings support the design of targeted clinical trials to evaluate the effect of HMB supplementation in older frail people with low HMB levels.
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Fragilidad , Valeratos , Masculino , Humanos , Femenino , Anciano , Vida Independiente , Suplementos Dietéticos , Músculo Esquelético/metabolismoRESUMEN
Antecedentes y objetivo El tratamiento de elección inicial del carcinoma basocelular (CBC) es la escisión quirúrgica. Esta debería ser completa para reducir el riesgo de recidiva. Nuestro objetivo es conocer las características de los CBC en nuestra área de salud, el porcentaje de márgenes afectos, y los factores de riesgo para una resección quirúrgica incompleta. Material y métodos Estudio observacional retrospectivo de los CBC intervenidos en el Área de Salud del Hospital Universitario Nuestra Señora de Candelaria entre el 1 de enero de 2014 y el 31 de diciembre de 2014. Recogemos datos demográficos, clínicos e histológicos, servicio responsable, abordaje quirúrgico y estado de los márgenes. Resultados Se diagnosticaron 966 CBC correspondientes a 776 pacientes, siendo el 9% biopsias, el 89% escisiones y el 2% rebanados. La mediana de edad fue de 71 años y el 52% eran hombres. La localización más frecuente fue la cara (59,1%). Se analizaron los márgenes quirúrgicos en 506 CBC. El 17% presentó afectación de márgenes. El porcentaje de márgenes afectos fue significativamente mayor en los tumores de la cara (22% cara vs. 10% otra localización) y en los de subtipo histológico de alto riesgo (OMS) (25% subtipo de alto riesgo vs. 15% bajo riesgo). Conclusiones Las características de nuestros pacientes con CBC se asemejan a las descritas previamente. La localización facial y el subtipo histológico son factores de riesgo para la resección incompleta del CBC. Por lo tanto, el abordaje quirúrgico inicial de los CBC con estas características ha de planearse de forma cuidadosa (AU)
Background and objective Surgical excision is the treatment of choice for basal cell carcinoma (BCC). Complete excision with clear margins is important for reducing the risk of recurrence. The aims of this study were to describe the characteristics of BCCs in our health care area, calculate the percentage of positive margins after surgical excision, and determine the risk factors for incomplete excision. Material and methods Retrospective observational study of BCCs that were surgically removed at Hospital Universitario Nuestra Señora de Candelaria, in Santa Cruz de Tenerife, Spain, between January 1, 2014 and December 31, 2014. Information was collected on demographic, clinical, and histologic variables, surgical approach, margin status, and the department responsible. Results In total, 966 BCCs were diagnosed in 776 patients. Nine percent of tumors with complete data were biopsied, 89% were surgically excised, and 2% were removed by shave excision. The median age of patients with excised tumors was 71 years and 52% were men. BCCs were most often located on the face (59.1%). Surgical margins were analyzed in 506 cases, 17% of which had positive margins. Incomplete excision was significantly more common in tumors located on the face (22% vs. 10% for other locations) and in high-risk subtypes according to the World Health Organization classification (25% vs. 15% for low-risk subtypes). Conclusions The characteristics of BCCs in our health care area are similar to those described elsewhere. Facial location and histologic subtype are risk factors for incomplete excision. Careful surgical planning is therefore important in the initial management of BCCs with these characteristics (AU)
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Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Anciano , Neoplasias Cutáneas/cirugía , Neoplasias Basocelulares/cirugía , Márgenes de Escisión , Estudios Retrospectivos , Recurrencia Local de Neoplasia , Factores de RiesgoRESUMEN
Background and objective Surgical excision is the treatment of choice for basal cell carcinoma (BCC). Complete excision with clear margins is important for reducing the risk of recurrence. The aims of this study were to describe the characteristics of BCCs in our health care area, calculate the percentage of positive margins after surgical excision, and determine the risk factors for incomplete excision. Material and methods Retrospective observational study of BCCs that were surgically removed at Hospital Universitario Nuestra Señora de Candelaria, in Santa Cruz de Tenerife, Spain, between January 1, 2014 and December 31, 2014. Information was collected on demographic, clinical, and histologic variables, surgical approach, margin status, and the department responsible. Results In total, 966 BCCs were diagnosed in 776 patients. Nine percent of tumors with complete data were biopsied, 89% were surgically excised, and 2% were removed by shave excision. The median age of patients with excised tumors was 71 years and 52% were men. BCCs were most often located on the face (59.1%). Surgical margins were analyzed in 506 cases, 17% of which had positive margins. Incomplete excision was significantly more common in tumors located on the face (22% vs. 10% for other locations) and in high-risk subtypes according to the World Health Organization classification (25% vs. 15% for low-risk subtypes). Conclusions The characteristics of BCCs in our health care area are similar to those described elsewhere. Facial location and histologic subtype are risk factors for incomplete excision. Careful surgical planning is therefore important in the initial management of BCCs with these characteristics (AU)
Antecedentes y objetivo El tratamiento de elección inicial del carcinoma basocelular (CBC) es la escisión quirúrgica. Esta debería ser completa para reducir el riesgo de recidiva. Nuestro objetivo es conocer las características de los CBC en nuestra área de salud, el porcentaje de márgenes afectos, y los factores de riesgo para una resección quirúrgica incompleta. Material y métodos Estudio observacional retrospectivo de los CBC intervenidos en el Área de Salud del Hospital Universitario Nuestra Señora de Candelaria entre el 1 de enero de 2014 y el 31 de diciembre de 2014. Recogemos datos demográficos, clínicos e histológicos, servicio responsable, abordaje quirúrgico y estado de los márgenes. Resultados Se diagnosticaron 966 CBC correspondientes a 776 pacientes, siendo el 9% biopsias, el 89% escisiones y el 2% rebanados. La mediana de edad fue de 71 años y el 52% eran hombres. La localización más frecuente fue la cara (59,1%). Se analizaron los márgenes quirúrgicos en 506 CBC. El 17% presentó afectación de márgenes. El porcentaje de márgenes afectos fue significativamente mayor en los tumores de la cara (22% cara vs. 10% otra localización) y en los de subtipo histológico de alto riesgo (OMS) (25% subtipo de alto riesgo vs. 15% bajo riesgo). Conclusiones Las características de nuestros pacientes con CBC se asemejan a las descritas previamente. La localización facial y el subtipo histológico son factores de riesgo para la resección incompleta del CBC. Por lo tanto, el abordaje quirúrgico inicial de los CBC con estas características ha de planearse de forma cuidadosa (AU)
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Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Anciano , Neoplasias Cutáneas/cirugía , Neoplasias Basocelulares/cirugía , Márgenes de Escisión , Estudios Retrospectivos , Recurrencia Local de Neoplasia , Factores de RiesgoRESUMEN
In Colombia, the first case of COVID-19 was confirmed on 6 March 2020. On 13 March 2023, Colombia registered 6,360,780 confirmed positive cases of COVID-19, representing 12.18% of the total population. The National Administrative Department of Statistics (DANE) in Colombia published in 2020 a COVID-19 vulnerability index, which estimates the vulnerability (per city block) of being infected with COVID-19. Unfortunately, DANE did not consider multiple factors that could increase the risk of COVID-19 (in addition to demographic and health), such as environmental and mobility data (found in the related literature). The proposed multidimensional index considers variables of different types (unemployment rate, gross domestic product, citizens' mobility, vaccination data, and climatological and spatial information) in which the incidence of COVID-19 is calculated and compared with the incidence of the COVID-19 vulnerability index provided by DANE. The collection, data preparation, modeling, and evaluation phases of the Cross-Industry Standard Process for Data Mining methodology (CRISP-DM) were considered for constructing the index. The multidimensional index was evaluated using multiple machine learning models to calculate the incidence of COVID-19 cases in the main cities of Colombia. The results showed that the best-performing model to predict the incidence of COVID-19 in Colombia is the Extra Trees Regressor algorithm, obtaining an R-squared of 0.829. This work is the first step toward a multidimensional analysis of COVID-19 risk factors, which has the potential to support decision making in public health programs. The results are also relevant for calculating vulnerability indexes for other viral diseases, such as dengue.
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BACKGROUND AND OBJECTIVE: Surgical excision is the treatment of choice for basal cell carcinoma (BCC). Complete excision with clear margins is important for reducing the risk of recurrence. The aims of this study were to describe the characteristics of BCCs in our health care area, calculate the percentage of positive margins after surgical excision, and determine the risk factors for incomplete excision. MATERIAL AND METHODS: Retrospective observational study of BCCs that were surgically removed at Hospital Universitario Nuestra Señora de Candelaria, in Santa Cruz de Tenerife, Spain, between January 1, 2014 and December 31, 2014. Information was collected on demographic, clinical, and histologic variables, surgical approach, margin status, and the department responsible. RESULTS: In total, 966 BCCs were diagnosed in 776 patients. Nine percent of tumors with complete data were biopsied, 89% were surgically excised, and 2% were removed by shave excision. The median age of patients with excised tumors was 71 years and 52% were men. BCCs were most often located on the face (59.1%). Surgical margins were analyzed in 506 cases, 17% of which had positive margins. Incomplete excision was significantly more common in tumors located on the face (22% vs. 10% for other locations) and in high-risk subtypes according to the World Health Organization classification (25% vs. 15% for low-risk subtypes). CONCLUSIONS: The characteristics of BCCs in our health care area are similar to those described elsewhere. Facial location and histologic subtype are risk factors for incomplete excision. Careful surgical planning is therefore important in the initial management of BCCs with these characteristics.
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Carcinoma Basocelular , Neoplasias Cutáneas , Masculino , Humanos , Anciano , Femenino , Neoplasias Cutáneas/epidemiología , Neoplasias Cutáneas/cirugía , Neoplasias Cutáneas/patología , España/epidemiología , Carcinoma Basocelular/epidemiología , Carcinoma Basocelular/cirugía , Carcinoma Basocelular/patología , Biopsia , Márgenes de EscisiónRESUMEN
INTRODUCTION: COVID-19 has affected people in several countries around the world. They experience respiratory symptoms that can be mild, moderate, or severe. Several reviews that characterize the risk factors of COVID-19 have been performed, but most address only risk factors associated with medical conditions, ignoring environmental and sociodemographic-socioeconomic factors. OBJECTIVE: This study aims at characterizing different risk factors in the published literature that influence contagion by COVID-19. METHODS: The review consists of three stages, including a systematic mapping with studies found in the Scopus database, an analysis of results, and finally the identification of relevant COVID-19 risk factors. RESULTS: A map of studies id provided considering two main groups: the type of research and context. Most studies consider risk factors associated with medical conditions, while research on other factors is scarce. CONCLUSIONS: Medical conditions such as diabetes, obesity, cardiovascular disease, hypertension, and factors such as age and sex, appear to be the ones that increase the risk of contracting COVID-19. Further research is needed on environmental, sociodemographic, and socioeconomic risk factors.
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COVID-19 , Humanos , COVID-19/epidemiología , Factores de RiesgoRESUMEN
Computerized techniques for image analysis are critical for progress in cell biology. The complexity of the data in current methods eliminates the need for manual image analysis and usually requires the application of multiple algorithms sequentially to the images. Our aim was to develop a software for immunohistochemical analysis of brain dopaminergic neurons combining several computational approaches to automatically analyze and quantify their number in the substantia nigra after a neurotoxic injury. For this purpose, we used a Parkinson's disease animal model to test our application. The dopaminergic neurotoxin, 6-hydroxydopamine, was administered in adult male rats to damage dopaminergic neurons in substantia nigra and to induce hemiparkinsonism. The lesion was corroborated by behavioral evaluation in response to apomorphine and amphetamine. The animals were euthanized and their brains processed for tyrosine hydroxylase immunohistochemistry for dopamine neuron identification. Neurons positive for tyrosine hydroxylase were evaluated in substantia nigra by light microscopy. The images were used to show quantification applicability. To test our software counting accuracy and validity, automatic dopamine neuron number was correlated with the data obtained by three independent observers. Several parameters were used to depict neuronal function in dataset images from control and lesioned brains. In conclusion, we could perform an automated quantification of dopaminergic neurons and corroborate the validity and accuracy of a freely available software.
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Neuronas Dopaminérgicas , Tirosina 3-Monooxigenasa , Animales , Neuronas Dopaminérgicas/metabolismo , Masculino , Oxidopamina/toxicidad , Ratas , Programas Informáticos , Sustancia Negra/metabolismo , Sustancia Negra/patología , Tirosina 3-Monooxigenasa/metabolismoRESUMEN
Sonidegib is a Hedgehog signalling pathway inhibitor approved for use in patients with advanced basal cell carcinoma (BCC) not eligible for surgery or radiotherapy. This report describes clinical experience with sonidegib in two patients with locally advanced BCC (one with a tumour adjacent to the right eye and the other with a tumour associated with the left ear) and in one patient with Gorlin syndrome. Two of the patients had recurrent and intractable tumours. Treatment with sonidegib 200 mg/day led to remission in both patients with locally advanced BCC within 7 months and to a reduction in the size and number of lesions after 4 months in the patient with Gorlin syndrome. Adverse effects reported in these patients were cramps, alopecia, ageusia and weight loss, all of which were mild and consistent with the known toxicity profile for sonidegib. Sonidegib has an important role to play in the effective treatment of challenging cases of advanced BCC. In parallel, a need remains to improve management protocols for patients with advanced BCC, particularly through earlier intervention and a multidisciplinary team approach.
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The coupling of PHB generation with NADH reoxidation is required to generate PHB as a fermentation product. A fundamental trait to accomplish this feature is to express a functional NADH-preferring acetoacetyl-CoA reductase, engaged in PHB accumulation. One way to obtain such a reductase is by engineering the cofactor preference of the acetoacetyl-CoA reductase encoded by the phaB1 gene from Cupriavidus necator (AARCn1). Aiming to have a deeper understanding of the structural determinants of the cofactor preference in AARCn1, and to obtain an NADH-preferring acetoacetyl-CoA reductase derived from this protein, some engineered enzymes were expressed, purified and kinetically characterized, together with the parental AARCn1. One of these engineered enzymes, Chimera 5, experimentally showed a selectivity ratio ((kcat/KM)NADH/(kcat/KM)NADPH) ≈ 18, which is 160 times higher than the selectivity ratio experimentally observed in the parental AARCn1. A thermodynamic-kinetic approach was employed to estimate the cofactor preference and flux capacity of Chimera 5 under physiological conditions. According to this approach, Chimera 5 could prefer NADH over NADPH between 25 and 150 times. Being a derivative of AARCn1, Chimera 5 should be readily functional in Escherichia coli and C. necator. Moreover, with the expected expression level, its activity should be enough to sustain PHB accumulation fluxes similar to the fluxes previously observed in these biotechnologically relevant cell factories.
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Cupriavidus necator , Oxidorreductasas de Alcohol/metabolismo , Cupriavidus necator/genética , Escherichia coli/genética , Escherichia coli/metabolismo , NAD/metabolismo , NADP/metabolismoRESUMEN
Enzymes adapted to cold temperatures are commonly characterized for having higher Michaelis-Menten constants (KM) values and lower optimum and denaturation temperature, when compared to other meso or thermophilic enzymes. Phenoloxidase (PO) enzymes are ubiquitous in nature, however, they have not been reported in spiders. It is the oxygen carrier protein hemocyanin (Hc), found at high concentrations in their hemolymph, which displays an inducible PO activity. Hence, we hypothesize that Hc-derived PO activity could show features of cold adaptation in alpine species. We analyzed the Hc from two species of Theraphosidae from different thermal environments: Euathlus condorito (2400 m a.s.l.) and Grammostola rosea (500 m a.s.l.). Hc was purified from the hemolymph of both spiders and was characterized by identifying subunit composition and measuring the sodium dodecyl sulfate (SDS)-induced PO activity. The high-altitude spider Hc showed higher PO activity under all conditions and higher apparent Michaelis-Menten constant. Moreover, the optimum temperature for PO activity was lower for E. condorito Hc. These findings suggest a potential adaptation at the level of Hc-derived PO activity in Euathlus condorito, giving insights on possible mechanisms used by this mygalomorph spider to occupy extremes and variable thermal environments.
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Ecosistema , Hemocianinas/metabolismo , Monofenol Monooxigenasa/metabolismo , Arañas/enzimología , Temperatura , Animales , Activación Enzimática , Arañas/fisiologíaRESUMEN
Oxygen supply implies higher production cost and reduction of maximum theoretical yields. Thus, generation of fermentation products is more cost-effective. Aiming to find a key piece for the production of (poly)-3-hydroxybutyrate (PHB) as a fermentation product, here we characterize an acetoacetyl-CoA reductase, isolated from a Candidatus Accumulibacter phosphatis-enriched mixed culture, showing a (kcatNADH/KMNADH)/(kcatNADPH/KMNADPH)>500. Further kinetic analyses indicate that, at physiological concentrations, this enzyme clearly prefers NADH, presenting the strongest NADH preference so far observed among the acetoacetyl-CoA reductases. Structural and kinetic analyses indicate that residues between E37 and P41 have an important role for the observed NADH preference. Moreover, an operon was assembled combining the phaCA genes from Cupriavidus necator and the gene encoding for this NADH-preferring acetoacetyl-CoA reductase. Escherichia coli cells expressing that assembled operon showed continuous accumulation of PHB under oxygen limiting conditions and PHB titer increased when decreasing the specific oxygen consumption rate. Taken together, these results show that it is possible to generate PHB as a fermentation product in E. coli, opening opportunities for further protein/metabolic engineering strategies envisioning a more efficient anaerobic production of PHB.
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Escherichia coli , NAD , Oxidorreductasas de Alcohol , Escherichia coli/genética , Hidroxibutiratos , PoliésteresRESUMEN
No disponible
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Humanos , Masculino , Anciano , Dermatofibrosarcoma/cirugía , Neoplasias Cutáneas/cirugía , Cirugía de Mohs/métodos , Colgajos Quirúrgicos/cirugía , Pared Abdominal/cirugía , Muslo/cirugía , Resultado del Tratamiento , Reproducibilidad de los ResultadosRESUMEN
BACKGROUND: Availability and opportunity of epilepsy diagnostic services is a significant challenge, especially in developing countries with a low number of neurologists. The most commonly used test to diagnose epilepsy is electroencephalogram (EEG). A typical EEG recording lasts for 20 to 30 minutes; however, a specialist requires much more time to read it. Furthermore, no evidence was found in the literature on open-source systems for the cost-effective management of patient information using electronic health records (EHR) that adequately integrate EEG analysis for automatic identification of abnormal signals. OBJECTIVE: To develop an integrated open-source EHR system for the management of the patients' personal, clinical, and EEG data, and for automatic identification of abnormal EEG signals. METHODS: The core of the system is an EHR and telehealth service based on the OpenMRS platform. On top of that, we developed an intelligent component to automatically detect abnormal segments of EEG tests using machine learning algorithms, as well as a service to annotate and visualize abnormal segments in EEG signals. Finally, we evaluated the intelligent component and the integrated system using precision, recall, and accuracy metrics. RESULTS: The system allowed to manage patients' information properly, store and manage the EEG tests recorded with a medical EEG device, and to detect abnormal segments of signals with a precision of 85.10%, a recall of 97.16%, and an accuracy of 99.92%. CONCLUSION: Digital health is a multidisciplinary field of research in which artificial intelligence is playing a significant role in boosting traditional health services. Notably, the developed system could significantly reduce the time a neurologist spends in the reading of an EEG for the diagnosis of epilepsy, saving approximately 65-75% of the time consumed. It can be used in a telehealth environment. In this way, the availability and provision of diagnostic services for epilepsy management could be improved, especially in developing countries where the number of neurologists is low.
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Carotenoids are plastid isoprenoid pigments that play critical roles in light harvesting, photoprotection, and phytohormone biosynthesis. They are also vitamin-A precursors and antioxidant molecules important for human nutrition. Apples (e.g. Malus x domestica Borkh), one of the most widely consumed fruits with high nutrient levels, have a very low carotenoid concentration in flesh, compared with other fruits and vegetables. This could be explained by a deficiency in carotenoid synthesis/accumulation and/or accelerated degradation. We analysed the contribution of M. domestica cv. 'Fuji' phytoene synthase (PSY) in the biosynthesis of carotenoids and determined that among four MdPSY genes present in the organism, MdPSY2 and MdPSY5 are highly expressed in leaves and during fruit ripening in line with an increment in carotenoid content in fruits. Furthermore, two representative polymorphic MdPSY2 variants were found, one with a Tyr358Phe substitution (MdPSY2_F) and the other that additionally has a six-amino-acid deletion in the signal peptide (MdPSY2_CG). MdPSY2, MdPSY5, MdPSY2_F and MdPSY2_CG are all localised in plastids. Interestingly, the polymorphic MdPSY2_F and MdPSY2_CG variants show lower enzymatic activity than the wild-type form in a heterologous complementation assay, which could be attributed to the Tyr358Phe substitution close to the active-site pocket, as was suggested by 3-D modelling analysis. The presence of polymorphic MdPSY2 variants with lower enzymatic activity could be partially responsible for the low carotenoid content in Fuji apple fruits.
Asunto(s)
Transferasas Alquil y Aril/genética , Malus/genética , Proteínas de Plantas/genética , Transferasas Alquil y Aril/química , Transferasas Alquil y Aril/metabolismo , Secuencia de Aminoácidos , Simulación por Computador , Malus/metabolismo , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Alineación de SecuenciaRESUMEN
The continuous search for novel enzyme backbones and the engineering of already well studied enzymes for biotechnological applications has become an increasing challenge, especially by the increasing potential diversity space provided by directed enzyme evolution approaches and the demands of experimental data generated by rational design of enzymes. In this work, we propose a semi-rational mutational strategy focused on introducing diversity in structurally variable regions in enzymes. The identified sequences are subjected to a progressive deletion of two amino acids and the joining residues are subjected to saturation mutagenesis using NNK degenerate codons. This strategy offers a novel library diversity approach while simultaneously decreasing enzyme size in the variable regions. In this way, we intend to identify and reduce variable regions found in enzymes, probably resulting from neutral drift evolution, and simultaneously studying the functional effect of said regions. This strategy was applied to Bacillus. subtilis lipase A (BSLA), by selecting and deleting six variable enzyme regions (named regions 1 to 6) by the deletion of two amino acids and additionally randomizing the joining amino acid residues. After screening, no active variants were found in libraries 1% and 4%, 15% active variants were found in libraries 2% and 3%, and 25% for libraries 5 and 6 (n = 3000 per library, activity detected using tributyrin agar plates). Active variants were assessed for activity in microtiter plate assay (pNP-butyrate), thermal stability, substrate preference (pNP-butyrate, -palmitate), and compared to wildtype BSLA. From these analyses, variant P5F3 (F41L-ΔW42-ΔD43-K44P), from library 3 was identified, showing increased activity towards longer chain p-nitrophenyl fatty acid esters, when compared to BSLA. This study allowed to propose the targeted region 3 (positions 40-46) as a potential modulator for substrate specificity (fatty acid chain length) in BSLA, which can be further studied to increase its substrate spectrum and selectivity. Additionally, this variant showed a decreased thermal resistance but interestingly, higher isopropanol and Triton X-100 resistance. This deletion-randomization strategy could help to expand and explore sequence diversity, even in already well studied and characterized enzyme backbones such as BSLA. In addition, this strategy can contribute to investigate and identify important non-conserved regions in classic and novel enzymes, as well as generating novel biocatalysts with increased performance in specific processes, such as enzyme immobilization.