An operational model for the optimal operation of the freeze-drying process

[Abstract] In this work an operational mathematical model for the freeze-drying process is derived. The model describes the state variables related to product quality and stability. Computational issues associated to the presence of a moving front are approached by using the Landau transform. Unknown model parameters are estimated using experimental data. The model is used to design optimal operation policies that reduce the process duration ensuring product quality

La vitamina A: reguladora de la espermatogénesis

La vitamina A es esencial para el desarrollo de las células germinales masculinas, la fertilidad y la espermatogénesis normal. El ácido retinoico, metabolito activo de la vitamina A, es necesario para la maduración de las espermatogonias y la entrada correcta de las células germinales en la profase meiótica en los testículos. La expresión de Stra8, fundamental en la meiosis y la espermatogénesis normal, está directamente relacionada con la disponibilidad del ácido retinoico. Este artículo se centra en el proceso de espermatogénesis y la interacción de la vitamina A con el ciclo seminífero, a fin de explicar la relación existente entre la disminución de los aportes de vitamina A, y las alteraciones presentadas en la espermatogénesis de humanos y algunos animales. También, se consideran los efectos de otros genes implicados en la síntesis de la vitamina A, su transporte y su degradación, y se discuten los posibles mecanismos celulares que pueden verse afectados por la falta de señalización de la vitamina A, en particular, la regulación del ciclo celular y la interacción célula-célula, puntos críticos para la espermatogénesis normal. En esta revisión de los 42 artículos científicos más relevantes del tema, se hizo una búsqueda de información en bases de datos como Science Direct, Scielo, Medline, Redalyc y Pubmed, durante los meses de enero a abril de 2014. Se encontró que en diversos estudios se ha demostrado que se puede controlar in vitro la proliferación de células germinales y su diferenciación, y además, que un deficiente consumo de vitamina A estaría relacionado con la disminución de la fertilidad masculina. Palabras clave: vitamina A, espermatogénesis, bloqueadores de espermatogénesis, meiosis, ácido retinoico, testículos.

Evolving spectrum but persistent high mortality of COVID-19 among patients on kidney replacement therapy in the vaccine era: the Spanish COVID-19 KRT Registry

COVID-19; Kidney transplant; DialysisCOVID-19; Trasplantament de ronyó; DiàlisiCOVID-19; Trasplante de riñón; DiálisisBackground Kidney replacement therapy (KRT) conferred a high risk for coronavirus disease 2019 (COVID-19) related mortality early in the pandemic. We evaluate the presentation, treatment and outcomes of COVID-19 in patients on KRT over time during the pandemic. Methods This registry-based study involved 6080 dialysis and kidney transplant (KT) patients with COVID-19, representing roughly 10% of total Spanish KRT patients. Epidemiology, comorbidity, infection, vaccine status and treatment data were recorded, and predictors of hospital admission, intensive care unit (ICU) admission and mortality were evaluated. Results Vaccine introduction decreased the number of COVID-19 cases from 1747 to 280 per wave. Of 3856 (64%) COVID-19 KRT patients admitted to the hospital, 1481/3856 (38%) were admitted during the first of six waves. Independent predictors for admission included KT and the first wave. During follow-up, 1207 patients (21%) died, 500/1207 (41%) during the first wave. Among vaccinated patients, mortality was 19%, mostly affecting KT recipients. Overall, independent predictors for mortality were older age, disease severity (lymphopaenia, pneumonia) and ICU rejection. Among patient factors, older age, male sex, diabetes, KT and no angiotensin receptor blockers (ARB) were independent predictors of death. In KT recipients, individual immunosuppressants were independent predictors of death. Over time, patient characteristics evolved and in later pandemic waves, COVID-19 was mainly diagnosed in vaccinated KT recipients; in the few unvaccinated dialysis patients, ICU admissions increased and mortality decreased (28% for the first wave and 16–22% thereafter). Conclusions The clinical presentation and outcomes of COVID-19 during the first wave no longer represent COVID-19 in KRT patients, as the pandemic has become centred around vaccinated KT recipients. Vaccines lowered the incidence of diagnosed COVID-19 and mortality. However, mortality remains high despite increased access to ICU care.We want to thank all the implicated Spanish centres for their altruist collaboration. A.O. research is supported by FIS/Fondos FEDER [PI18/01366, PI19/00588, PI19/00815, DTS18/00032, ERA-PerMed-JTC2018 (KIDNEY ATTACK AC18/00064 and PERSTIGAN AC18/00071, ISCIII-RETIC REDinREN RD016/0009)], Sociedad Española de Nefrología, FRIAT, Comunidad de Madrid en Biomedicina B2017/BMD-3686 CIFRA2-CM. Instituto de Salud Carlos III (ISCIII) RICORS program to RICORS2040 (RD21/0005/0001), FEDER funds

Tejidos sin fronteras

La presente biocrónica surge de la reflexión y aproximación al ejercicio investigativo de maestros en formación, realizado durante la salida de campo a Leticia-Amazonas para sexto semestre de la Licenciatura en Biología de la Universidad Pedagógica Nacional. En dicha práctica de campo se desarrolló una caracterización sociocultural del contexto regional mediante la interacción, apreciación, descripción e interpretación de la “Memoria Biocultural” desde lo propuesto por Toledo y Barrera (2016), quienes la entienden como un conjunto de conocimientos, creencias y prácticas de las comunidades para perpetuar sus tradiciones. Allí, fue posible interactuar con indígenas Uitoto, Tikuna y Miraña, en diferentes espacios como la Maloca amazónica, recorridos y estancias en su territorio, donde se aplicaron entrevistas semiestructuradas y registraron cada una de las experiencias en el diario de campo. El objetivo de este acercamiento, fue identificar cómo los mayores incitan e incentivan, de manera consciente e inconsciente a la generación más joven, a mantener los comportamientos tradicionales y los diferentes modos de pensar que son propios de sus culturas, este proceso se denomina endoculturación (Harris, 2001). De igual manera, esta práctica permitió a los maestros en formación construir conocimiento acerca de las comunidades indígenas y las problemáticas que se presentan en relación con la transmisión de su memoria biocultural (conocimientos, creencias y prácticas), además, reflexionar respecto al papel del maestro en contextos culturalmente diversos y la enseñanza de la Biología desde otra perspectiva distinta a la occidental

Insomnia Symptoms in Patients With Substance Use Disorders During Detoxification and Associated Clinical Features

Background: Insomnia is highly prevalent in patients with substance use disorders (SUD), and it has been related to a worse course of addiction. Insomnia during detoxification in a hospital has not been adequately studied. This study aims to compare sociodemographic, clinical, and psychopathological characteristics of SUD patients undergoing a detoxification program, by comorbidity and insomnia symptoms. Methodology: We recruited 481 patients who received pharmacological and psychotherapeutic treatment for detoxification. They were evaluated through semi-structured interviews, standardized questionnaires, and a specific sleep log. A bivariate and multivariate analysis of the data was performed. Results: Insomnia was reported by 66.5% patients, with sleep-maintenance insomnia the most frequent issue, followed by early morning awakening and sleep-onset insomnia. Patients with alcohol use disorder and cannabis use disorder had higher prevalence of sleep-onset insomnia. Patients with cocaine and heroin use disorder had higher prevalence of sleep-maintenance insomnia. Independent factors that allowed the identification of insomnia symptoms included being female (OR: 3.43), polysubstance use (OR: 2.85), comorbid anxiety disorder (OR: 2.02), and prior admission for detoxification (OR: 1.22). Conclusions: Insomnia symptoms are very prevalent in patients admitted for detoxification. The diagnosis and therapeutic strategies for the insomnia symptoms should be improved, especially in women and in patients with greater addiction severity and with anxiety disorders

Determinación de genes que codifican la resistencia de betalactamasas de espectro extendido en bacilos Gram negativos aislados de urocultivos

Introduction: Extended spectrum beta lactamases (ESBL) are a group of enzymes that confers bacterial resistance to a wide spectrum of betalactam antibiotics. These are coded in plasmids and should be studied as surveillance tools to watch the behavior of microorganisms towards the use of antibiotics. Objective: To determine the resistance coding genes in gram-negative bacilli with ESBL phenotype isolated from urine cultures, in a health services institution in the department of Boyacá. Methods: An observational, descriptive, cross-sectional study was carried out. Nineteen different strains with ESBL phenotype were identified, by following the Clinical and Laboratory Standards Institute (CLSI M100-S23) guidelines; and the microbiological identification concordance index was established. Through polimerase chain reaction (PCR) technique standardization, the presence of blaTEM, blaSHV, blaCTX, and Amp-C genes was determined for the 19 strains mentioned. Results: All of the nineteen strains with ESBL phenotype (100%) were found to be resistant to a mpiciline; 12 (63,2%) resistant to ampicilin sulbactam; 17 (89,5%) to cephalothin; 16 (84,2 %) to cefuroxime; 17 (89,5%) to cefotaxime; 17 (89,5%) to ceftriaxione, and 14 (73,7%) to cefepime. Gene amplification was performed on 18 isolates, 12 (61,11%) of them possibly presented the blaCTX gene; 10 (55,6%) the AmpC gene; 9 (50 %) the blaSHV gene, and 7 (38,88%) the blaTEM gene. Conclusion: The presence of blaCTX, AmpC, blaSHV, and blaTEM genes represents epidemiological importance, probably because of its capacity to mobilize genetic resistance information inside the hospitalary environment in which they have a clear epidemic potential.Introducción. Las betalactamasas de espectro extendido (BLEE) son un grupo de enzimas que confieren resistencia bacteriana a un amplio espectro de antibióticos betalactámicos codificados en plásmidos y que deben estudiarse como herramientas de vigilancia del comportamiento de microorganismos frente al uso de antibióticos. Objetivo. Determinar los genes que codifican la resistencia en bacilos gramnegativos con fenotipo BLEE aislados de urocultivos, en una institución prestadora de servicios de salud del departamento de Boyacá. Métodos. Se llevó a cabo un estudio observacional, descriptivo y de corte transversal. Se identificaron 19 cepas resistentes con fenotipo BLEE, siguiendo los lineamientos del Clinical and Laboratory Standards Institute (CLSI M100-S23), y se estableció el índice de concordancia para la identificación microbiológica. Por medio de la estandarización de la técnica de reacción en cadena de la polimerasa (PCR), se determinó la presencia de los genes blaTEM, blaSHV, blaCTX y Amp-C en estas 19 cepas. Resultados. Se encontró que las 19 cepas con fenotipo BLEE (100 %) presentaban resistencia a la ampicilina; 12 (63,2 %) a la ampicilina-sulbactam; 17 (89,5 %) a la cefalotina; 16 (84,2 %) a la cefuroxima; 17 (89,5%) a la cefotaxima; 17 (89,5 %) a la ceftriaxona y 14 (73,7%) al cefepime. En 18 aislamientos se hizo amplificación de los genes, de los cuales 12 (61,11 %) posiblemente presentaron el gen blaCTX; 10 (55,6 %) el gen AmpC; 9 (50 %) el gen blaSHV y 7 (38,88 %) el gen blaTEM. Conclusión. La presencia de los genes blaCTX, AmpC, blaSHV y blaTEM presenta importancia epide-miológica, probablemente por la capacidad para movilizar la información genética de la resistencia en el ambiente hospitalario, donde tienen un claro potencial epidémico.  Palabras clave: antibiótico, farmacorresistencia bacteriana, betalactamasa

Erosive features caused by a magellanic penguin (spheniscus magellanicus) colony on martillo island, beagle channel, Argentina

Desde 1976 en la Isla Martillo (Canal Beagle, 54°54´26? S; 67°22´58? O) se asienta una colonia de pingüinos de Magallanes (Spheniscus magellanicus). Allí se identifican geoformas de origen glacial y marino, entre las que se destacan: drumlin, terrazas glacifluviales y marinas, y playas. La vegetación de la isla está compuesta por fragmentos bosque localizados mayoritariamente en el E de la isla, y la superficie restante está cubierta de arbustos, matas y pastos. Este trabajo presenta a los pingüinos como agentes erosivos en las geoformas terrestres, glaciares y marinas. Se realizó una evaluación multi-criterio de relevamiento de campo. La geo data base se trabajó en el entorno GIS Quantum GIS® 3.2.1, utilizando imágenes satelitales y un modelo digital del terreno (MDT) de 12 m de resolución espacial, como base de referencia visual. Los datos morfométricos y la evaluación multi-criterio se recopilaron durante el verano austral 2016-2017. Se tomaron muestras de los suelos y sedimentos de cada forma de relieve (drumlin, terraza glacifluvial, playa elevada y playa) para analizar el tamaño de partícula, para determinar si existe alguna relación entre los parámetros morfométricos de la cueva y los sedimentos. Se definieron cuatro clases de bioerosión en función de las características de erosión observadas en el campo. "Moderada" fue la clase de erosión predominante, en la parte E-NE de la isla. Los rasgos erosivos se desarrollan principalmente en la ladera con orientación N del E de la isla, donde un barranco natural drena el agua de lluvia y sobre las superficies de las terrazas glacifluviales y marinas. Las características erosivas como las cuevas y los puentes se desarrollan principalmente en drumlins limosos. Los pedestales se desarrollan en suelos desnudos y matas. Los senderos y las grietas también se describieron como bioerosión. No se registraron características erosivas en la parte oeste de la isla. El mapa de bioerosión es uno de los insumos para el análisis de degradación ambiental y la investigación dinámica de la población que se está realizando en la colonia de pingüinos de Magallanes en la isla Martillo, Canal Beagle.An active Magellanic penguin (Spheniscus magellanicus) colony has been established on Martillo Island, Beagle Channel (54°54´26? S; 67°22´58? W) since 1976. It is located in remnants of eroded drumlins placed in both ending and joined by gravel terraces of glaciofluvial and marine origin. Forest patches occupy the eastern side of the island while most of the island is covered by bushes, tussocks and grasses. This paper presents penguins as bio-erosion agents on glacial and marine landforms. An analysis of multiple criteria surveyed in the field was performed, using Quantum GIS® 3.2.1 with remote sensing images and a digital model terrain of 12 m resolution. The morphometric data and multicriterial evaluation were collected during 2016-2017 austral summer. Soils and sediments of each landform (drumlin, glaciofluvial terrace, raised beach and beach) were sampled for particle size analysis, to determine if there is any relationship between the morphometric parameters of the cave and the sediments. Four bio-erosion classes were defined based on the erosion features observed in the field. ?Moderate? was the prevailing erosion class recorded, in the E-NE part of the island. Bio-erosion features are mainly developed on the N facing slope of the east of the island, where a natural gully drains rainfall water, and over the glaciofluvial and marine terrace surfaces. Erosive features such as caves and bridges are mainly developed in silty drumlins. Pedestals are developed on bare soils and tussocks. Trails and cracks were also described as bio-erosion. No erosive features were recorded in the W part of the island. The bio-erosion map is one of the inputs for environmental degradation analysis and population dynamic research which is being done in the Magellanic penguin colony on Martillo Island, Beagle Channel.Fil: Quiroga, Diego Rubén Andrés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina. Universidad Nacional de Tierra del Fuego; ArgentinaFil: Coronato, Andrea Maria Josefa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina. Universidad Nacional de Tierra del Fuego; ArgentinaFil: Scioscia, Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; ArgentinaFil: Raya Rey, Andrea Nélida. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina. Universidad Nacional de Tierra del Fuego; ArgentinaFil: Schiavini, Adrian Carlos Miguel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; ArgentinaFil: Santos González, Javier. Universidad de León; EspañaFil: López, C.R.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; ArgentinaFil: Redondo Vega, José María. Universidad de León; Españ

Dysautonomia in COVID-19 Patients: A Narrative Review on Clinical Course, Diagnostic and Therapeutic Strategies

IntroductionOn March 11, 2020, the World Health Organization sounded the COVID-19 pandemic alarm. While efforts in the first few months focused on reducing the mortality of infected patients, there is increasing data on the effects of long-term infection (Post-COVID-19 condition). Among the different symptoms described after acute infection, those derived from autonomic dysfunction are especially frequent and limiting. ObjectiveTo conduct a narrative review synthesizing current evidence of the signs and symptoms of dysautonomia in patients diagnosed with COVID-19, together with a compilation of available treatment guidelines. ResultsAutonomic dysfunction associated with SARS-CoV-2 infection occurs at different temporal stages. Some of the proposed pathophysiological mechanisms include direct tissue damage, immune dysregulation, hormonal disturbances, elevated cytokine levels, and persistent low-grade infection. Acute autonomic dysfunction has a direct impact on the mortality risk, given its repercussions on the respiratory, cardiovascular, and neurological systems. Iatrogenic autonomic dysfunction is a side effect caused by the drugs used and/or admission to the intensive care unit. Finally, late dysautonomia occurs in 2.5% of patients with Post-COVID-19 condition. While orthostatic hypotension and neurally-mediated syncope should be considered, postural orthostatic tachycardia syndrome (POTS) appears to be the most common autonomic phenotype among these patients. A review of diagnostic and treatment guidelines focused on each type of dysautonomic condition was done. ConclusionSymptoms deriving from autonomic dysfunction involvement are common in those affected by COVID-19. These symptoms have a great impact on the quality of life both in the short and medium to long term. A better understanding of the pathophysiological mechanisms of Post-COVID manifestations that affect the autonomic nervous system, and targeted therapeutic management could help reduce the sequelae of COVID-19, especially if we act in the earliest phases of the disease

A combined strategy involving Sanger and 454 pyrosequencing increases genomic resources to aid in the management of reproduction, disease control and genetic selection in the turbot (Scophthalmus maximus)

Background: Genomic resources for plant and animal species that are under exploitation primarily for human consumption are increasingly important, among other things, for understanding physiological processes and for establishing adequate genetic selection programs. Current available techniques for high-throughput sequencing have been implemented in a number of species, including fish, to obtain a proper description of the transcriptome. The objective of this study was to generate a comprehensive transcriptomic database in turbot, a highly priced farmed fish species in Europe, with potential expansion to other areas of the world, for which there are unsolved production bottlenecks, to understand better reproductive- and immune-related functions. This information is essential to implement marker assisted selection programs useful for the turbot industry. Results: Expressed sequence tags were generated by Sanger sequencing of cDNA libraries from different immunerelated tissues after several parasitic challenges. The resulting database (“Turbot 2 database”) was enlarged with sequences generated from a 454 sequencing run of brain-hypophysis-gonadal axis-derived RNA obtained from turbot at different development stages. The assembly of Sanger and 454 sequences generated 52,427 consensus sequences (“Turbot 3 database”), of which 23,661 were successfully annotated. A total of 1,410 sequences were confirmed to be related to reproduction and key genes involved in sex differentiation and maturation were identified for the first time in turbot (AR, AMH, SRY-related genes, CYP19A, ZPGs, STAR FSHR, etc.). Similarly, 2,241 sequences were related to the immune system and several novel key immune genes were identified (BCL, TRAF, NCK, CD28 and TOLLIP, among others). The number of genes of many relevant reproduction- and immune-related pathways present in the database was 50–90% of the total gene count of each pathway. In addition, 1,237 microsatellites and 7,362 single nucleotide polymorphisms (SNPs) were also compiled. Further, 2,976 putative natural antisense transcripts (NATs) including microRNAs were also identified Conclusions: The combined sequencing strategies employed here significantly increased the turbot genomic resources available, including 34,400 novel sequences. The generated database contains a larger number of genes relevant for reproduction- and immune-associated studies, with an excellent coverage of most genes present in many relevant physiological pathways. This database also allowed the identification of many microsatellites and SNP markers that will be very useful for population and genome screening and a valuable aid in marker assisted selection programs.The current work was granted by the Spanish Government thanks to a Consolider Project (Project Aquagenomics, ref. CDS2007-0002) and to projects AGL2006-13158-C03 and AGL2009-13282-C01 and C02. LR was supported by an Aquagenomics postdoctoral contract and BGP was supported by an Isidro Parga Pondal research fellowship from the Xunta de Galicia (Spain).S