Abstract
Background and Aims
Delayed graft function (DGF) is a common complication after renal transplant. Definitions of DGF are based on analysis of estimated glomerular filtration rate (eGFR) ...underlying the plasma creatinine fluctuations after renal transplant. We tried to validate an early parameter of DGF in a renal transplant population based on the kinetic estimation of glomerular filtration rate, since this formula adds a quantitative dimension to the assessment of kidney function, and consequently predicting DGF could get a better post-transplant management.
Method
This is a longitudinal study of 886 renal transplant recipients from our center during the first post-transplant month. As we are searching for functional biochemical markers in renal transplant from decesased donors, we excluded patients with primary gtaft disfunction.The final simple was composed of 574 adult kidney transplant recipients, 348 renal transplant from donors after circulatory death (DCD) and 226 from donors after brain death (DBD). The following are analyzed 5creatinine concentrations, serum Lactate dehydrogenase (LDH) and urinary creatinine excretion rate (CER).
Results
In DCD there was a significant correlation between DGF duration and all KeGFR and CER determinations during the first post-transplant week. The parameters that achieved the best correlation to predict DGF were KeGFR (r = 0.515; p<0.001) and CER on the fourth day (r = 0.584; p<0.001) (Figure 1). In the DBD, a weak correlation was observed between DGF duration and KeGFR determinations in the first days, being KeGFR at the fourth day the one that presented the highest correlation (r = 0.59 p<0.001). We observed that serum LDH on the first day in the DBD group is associated with worse renal graft function at first, third month and one year after transplantation (p<.045, p<.05 and p<.067 respectively).
Conclusion
The determination of KeGFR and CER could predict the duration of DGF, especially in DCD recipients. DCD recipients with DGF have significantly better graft survival at one year than DBD recipients with DGF. (p<.001).
La programación orientada a objetos en C++ facilita la codificación de algoritmos respecto al paradigma estructurado del lenguaje C, este echo suele provocar un cuestionamiento válido entre los ...estudiantes ¿por qué codificar cadenas con memoria dinámica en C cuando los objetos String en C++ evitan ese trabajo? Este tipo de inquietudes permiten gestar casos de estudio de Aprendizaje Basado en Problemas (ABP). En el presente artículo se reporta el contraste de los lenguajes C y C++ a través de la generación multihilo de cadenas L-System usando computadoras personales a disposición de estudiantes de ingeniería en computación. Se realizaron cien corridas para el cálculo de tiempos promedio de ejecución para dos tipos de L-System considerando el procesamiento con balanceo y sin balanceo de carga para dos, cuatro y ocho hilos. Los resultados muestran una mayor velocidad de ejecución para el lenguaje C, pero diferencias interesantes en el Speed Up respecto al lenguaje C++. Al final se concluye que la mejor eficiencia se logra paralelizando con multihilos, siempre y cuando el volumen de los datos sea considerable y esté balanceado, además, la cantidad de hilos no debe rebasar el número de núcleos. Bien vale la pena que los estudiantes lleguen a estas conclusiones mediante el aprendizaje por descubrimiento a través de un caso de estudio.
We propose a methodology for verifying security properties of network protocols at design level. It can be separated in two main parts: context and requirements analysis and informal verification; ...and formal representation and procedural verification. It is an iterative process where the early steps are simpler than the last ones. Therefore, the effort required for detecting flaws is proportional to the complexity of the associated attack. Thus, we avoid wasting valuable resources for simple flaws that can be detected early in the verification process. In order to illustrate the advantages provided by our methodology, we also analyze three real protocols.
In this work we present and formally analyze CHAT-SRP (CHAos based Tickets-Secure Registration Protocol), a protocol to provide interactive and collaborative platforms with a cryptographically robust ...solution to classical security issues. Namely, we focus on the secrecy and authenticity properties while keeping a high usability. In this sense, users are forced to blindly trust the system administrators and developers. Moreover, as far as we know, the use of formal methodologies for the verification of security properties of communication protocols isn't yet a common practice. We propose here a methodology to fill this gap, i.e., to analyse both the security of the proposed protocol and the pertinence of the underlying premises. In this concern, we propose the definition and formal evaluation of a protocol for the distribution of digital identities. Once distributed, these identities can be used to verify integrity and source of information. We base our security analysis on tools for automatic verification of security protocols widely accepted by the scientific community, and on the principles they are based upon. In addition, it is assumed perfect cryptographic primitives in order to focus the analysis on the exchange of protocol messages. The main property of our protocol is the incorporation of tickets, created using digests of chaos based nonces (numbers used only once) and users' personal data. Combined with a multichannel authentication scheme with some previous knowledge, these tickets provide security during the whole protocol by univocally linking each registering user with a single request. ..
Abstract
Background and Aims
Submediterranean areas are rich ecotones, where slight modifications in environmental conditions can lead to substantial changes in the composition of plant communities. ...They thus offer an ideal scenario to examine plant community assembly. In this study, we followed a trait-based approach including intraspecific variability to elucidate (1) the relationship between niche occupancy components and species richness, (2) the processes governing the assembly of these communities and (3) the contribution of intraspecific trait variability in shaping the functional trait space.
Methods
We measured eight morphological and chemical traits in 405 individuals across 60 plots located in different forest communities (Mediterranean, Eurosiberian and Mixed) coexisting within a submediterranean ecosystem in central Spain. We calculated three niche occupancy components related to Hutchinson’s n-dimensional hypervolumes: the total functional volume of the community, the functional overlap between species within the community and the average functional volume per species, and then used null models to explore the relative importance of habitat filtering, limiting similarity and intraspecific variability as assembly patterns.
Key Results
Both habitat filtering and niche differentiation drive the community assembly of Mediterranean communities, whereas limiting similarity and hierarchical competition shape Eurosiberian communities. Intraspecific responses were mostly explained by shifts in species niches across the functional space (changes in the position of the centroids of hypervolumes).
Conclusions
Different assembly mechanisms govern the structure of Mediterranean, Eurosiberian and Mixed plant communities. Combining niche occupancy components with a null model approach at different spatial scales offers new insights into the mechanisms driving plant community assembly. Consideration of intraspecific variability is key for understanding the mechanisms governing species coexistence in species-rich ecotones.
Ursolic (UA), oleanolic (OA) and rosmarinic (RA) acids are bioactive metabolites found in
that have generated interest for their health benefits, which include antimicrobial, antioxidant, ...antimutagenic, gastroprotective, antidiabetic, antihypertensive and anti-inflammatory properties, among others. To date, very few attempts have been made to evaluate the potential for simultaneous production of these bioactive compounds, using a biotechnological approach. Hairy root cultures offer a biotechnology approach that can be used to study the factors affecting the biosynthesis and the production of UA, OA and RA. In the current study, we established hairy root cultures of
and evaluated the effect of sucrose on biomass accumulation, and the effect of different concentrations and times of exposure of methyl jasmonate (MeJA), on the accumulation of UA, OA and RA.
Leaves from plants of
were inoculated with
strain ATCC 15834
PCR of
gene confirmed the transgenic nature of hairy roots. Hairy roots were subcultured in semisolid MSB5 medium, supplemented with 15, 30, 45 or 60 g/L sucrose and after 4 weeks, dry weight was determined. The accumulation of UA, OA and RA of wild plants and hairy roots were determined by HPLC. Finally, the hairy roots were treated with 0, 100, 200 and 300
M of MeJA and the content of bioactive compounds was analyzed, after 24, 48 and 72 h.
High frequency transformation (75%) was achieved, using leaf explants from axenic seedlings, infected with
. The hairy roots showed an enhanced linear biomass accumulation, in response to the increase in sucrose concentration. The hairy root cultures in MSB5 medium, supplemented with 45 g/L sucrose, were capable to synthesizing UA (0.29 ± 0.00 mg/g DW), OA (0.57 ± 0.00 mg/g DW) and RA (41.66 ± 0.31 mg/g DW), about two, seven and three times more, respectively, than in roots from wild plants. Elicitation time and concentration of MeJA resulted in significant enhancement in the production of UA, OA and RA, with treatments elicited for 24 h, with a concentration of 300
M of MeJA, exhibiting greatest accumulation.
This is the first report on development of hairy root cultures of
. Future studies should aim towards further improving triterpenes and polyphenolic compound production in hairy roots of
for use in the pharmaceutical and biotechnological industry.
Introducción: Los estudios dendrocronológicos en México se han basado principalmente en las coníferas, mientras que las especies de madera dura han sido poco estudiadas. Este ha sido el caso del ...género Quercus, con una alta diversidad taxonómica en el país pero que no ha sido estudiado con fines dendrocronológicos, a pesar de los valores ecológicos y económicos de sus especies. Objetivo: En la presente investigación se determinó el potencial dendroclimático de Quercus sideroxyla en el noroeste de México, y su relación con variables climáticas como precipitación y temperatura. Métodos: La investigación se desarrolló en el estado de Durango en el ejido Chavarría Viejo en las coordenadas (23º43’ N & 105º33’ W), se recolectaron muestras de 5 a 7 cm en dos sitios bajo aprovechamiento forestal y se procesaron mediante técnicas dendrocronológicas convencionales. Resultados: Se desarrolló una cronología de ancho de anillo total, la cual se compuso por 30 muestras de 16 árboles para el período de 1917 a 2018 (101 años). Se obtuvieron valores de intercorrelación entre series de 0.43, de sensibilidad media de 0.36, relación señal-ruido de 3.53 y autocorrelación de primer orden (0.58). En cuanto a la relación clima-crecimiento, los valores de índice de ancho de anillo se correlacionaron con datos de la estación climática más cercana al sitio de estudio; donde la precipitación invierno-primavera (enero-mayo) fue la variable de mayor influencia en el crecimiento de la especie. Conclusiones: Con base en los parámetros dendrocronológicos se demuestra el alto potencial de la especie para ser empleada en estudios dendroclimáticos en la región, la respuesta de la especie a la precipitación es similar al de las coníferas con las que cohabita.
In B-cell precursor acute lymphoblastic leukaemia (B-ALL), the identification of additional genetic alterations associated with poor prognosis is still of importance. We determined the frequency and ...prognostic impact of somatic mutations in children and adult cases with B-ALL treated with Spanish PETHEMA and SEHOP protocols.
Mutational status of hotspot regions of TP53, JAK2, PAX5, LEF1, CRLF2 and IL7R genes was determined by next-generation deep sequencing in 340 B-ALL patients (211 children and 129 adults). The associations between mutation status and clinicopathological features at the time of diagnosis, treatment outcome and survival were assessed. Univariate and multivariate survival analyses were performed to identify independent prognostic factors associated with overall survival (OS), event-free survival (EFS) and relapse rate (RR).
A mutation rate of 12.4% was identified. The frequency of adult mutations was higher (20.2% vs 7.6%, P=0.001). TP53 was the most frequently mutated gene (4.1%), followed by JAK2 (3.8%), CRLF2 (2.9%), PAX5 (2.4%), LEF1 (0.6%) and IL7R (0.3%). All mutations were observed in B-ALL without ETV6-RUNX1 (P=0.047) or BCR-ABL1 fusions (P<0.0001). In children, TP53mut was associated with lower OS (5-year OS: 50% vs 86%, P=0.002) and EFS rates (5-year EFS: 50% vs 78.3%, P=0.009) and higher RR (5-year RR: 33.3% vs 18.6% P=0.037), and was independently associated with higher RR (hazard ratio (HR)=4.5; P=0.04). In adults, TP53mut was associated with a lower OS (5-year OS: 0% vs 43.3%, P=0.019) and a higher RR (5-year RR: 100% vs 61.4%, P=0.029), whereas JAK2mut was associated with a lower EFS (5-year EFS: 0% vs 30.6%, P=0.035) and a higher RR (5-year RR: 100% vs 60.4%, P=0.002). TP53mut was an independent risk factor for shorter OS (HR=2.3; P=0.035) and, together with JAK2mut, also were independent markers of poor prognosis for RR (TP53mut: HR=5.9; P=0.027 and JAK2mut: HR=5.6; P=0.036).
TP53mut and JAK2mut are potential biomarkers associated with poor prognosis in B-ALL patients.
Objective: Posterior reversible encephalopathy syndrome (PRES) has been robustly associated with preeclampsia, hyperperfusion or endothelial dysfunction suggested as possible mechanisms. In this ...article, we report an illustrative case of this complication in a patient with risk factors for hypertensive disorders in pregnancy, including advanced maternal age and donor oocyte fertilization.
Case report: We present a case of a 40-year-old pregnant, donor oocyte recipient with sudden decreased visual acuity accompanied by hypertension, proteinuria and tonic-clonic seizures. Magnetic resonance imaging (MRI) of the brain showed bilateral lesions in the parieto-occipital regions suggestive of vasogenic edema, leading us to suspect posterior reversible encephalopathy syndrome. The patient underwent an emergency cesarean section and labetalol and magnesium sulfate were administered intravenously. The neurological symptoms and radiological findings resolved following delivery and the patient’s blood pressure normalized, supporting the diagnosis of posterior reversible encephalopathy syndrome.
Conclusion: Pregnancy by donor oocyte fertilization may entail a higher risk of eclampsia and associated posterior reversible encephalopathy syndrome.
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