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Most proteins associate into multimeric complexes with specific architectures1,2, which often have functional properties such as cooperative ligand binding or allosteric regulation3. No detailed knowledge is available about how any multimer and its functions arose during evolution. Here we use ancestral protein reconstruction and biophysical assays to elucidate the origins of vertebrate haemoglobin, a heterotetramer of paralogous α- and ß-subunits that mediates respiratory oxygen transport and exchange by cooperatively binding oxygen with moderate affinity. We show that modern haemoglobin evolved from an ancient monomer and characterize the historical 'missing link' through which the modern tetramer evolved-a noncooperative homodimer with high oxygen affinity that existed before the gene duplication that generated distinct α- and ß-subunits. Reintroducing just two post-duplication historical substitutions into the ancestral protein is sufficient to cause strong tetramerization by creating favourable contacts with more ancient residues on the opposing subunit. These surface substitutions markedly reduce oxygen affinity and even confer cooperativity, because an ancient linkage between the oxygen binding site and the multimerization interface was already an intrinsic feature of the protein's structure. Our findings establish that evolution can produce new complex molecular structures and functions via simple genetic mechanisms that recruit existing biophysical features into higher-level architectures.
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Evolución Molecular , Hemoglobinas/metabolismo , Regulación Alostérica , Sitios de Unión/genética , Hemo/metabolismo , Hemoglobinas/química , Humanos , Hierro/metabolismo , Modelos Moleculares , Oxígeno/metabolismo , Multimerización de Proteína/genética , Estructura Cuaternaria de Proteína/genética , Subunidades de Proteína/química , Subunidades de Proteína/metabolismoRESUMEN
A novel papillomavirus (PV) associated with hyperplastic nodules scattered over the muco-cutaneous border of the oral cavity of a dead, wild, subadult northern sea otter Enhydra lutris kenyoni (NSO) in 2004 in Homer, Alaska, USA, was genetically characterized. Primers for the amplification of 2 large overlapping DNA fragments that contained the complete genome of the NSO PV were designed. Sanger methodology generated sequences from which new specific primers were designed for the primer-walking approach. The NSO PV genome consists of 8085 nucleotides and contains an early region composed of E6, E7, E1, and E2 open reading frames (ORFs), an E4 ORF (contained within E2) lacking an in-frame proximal ATG start codon, an unusually long (907 nucleotide) stretch lacking any ORFs, a late region that contains the capsid genes L2 and L1, and a non-coding regulatory region (ncRR). This NSO PV has been tentatively named Enhydra lutris kenyoni PV2 (ElkPV2). Pairwise and multiple sequence alignments of the complete L1 ORF nucleotides and concatenated E1-E2-L1 amino acid sequences showed that the NSO PV is a novel PV, phylogenetically most closely related to southern sea otter PV1. The carboxy end of the E6 oncoprotein does not contain the PDZ-binding motif with a strong correlation with oncogenicity, suggesting a low-risk PV, which is in agreement with histopathological findings. However, the ElkPV2 E7 oncoprotein does contain the retinoblastoma (pRb) binding domain LXCXE (LQCYE in ElkPV2), associated with oncogenicity in some high-risk PVs. Further studies on the prevalence and clinical significance of ElkPV2 infections in NSO are needed.
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Lambdapapillomavirus , Nutrias , Animales , Alaska/epidemiología , Nucleótidos , Proteínas OncogénicasRESUMEN
BACKGROUND: Splenic cysts are uncommon and very rarely malignant therefore their treatment isn't standardized. In case of symptomatic cysts different surgical approaches have been suggested. Primary malignant lymphoma of the spleen comprises less than 1% of non-Hodgkin's lymphomas. To our knowledge, only 203 cases of splenic large B-cell lymphoma (LBCL) have been reported to date and only 2 of them were fibrin-associated splenic cysts. CASE PRESENTATION: 27-year-old model with a 19 × 13 cm splenic cyst without data of malignancy in the preliminary study and therefore treated with laparoscopic deroofing. After histological diagnosis of LBCL with a fibrin/EBV-associated splenic pseudocyst, the patient received 4 cycles of Rituximab and a laparoscopic splenectomy was performed due to resurgence of the pseudocyst. No evidence of malignancy has been found during follow up (EBV viral load every 3 months during the first year, PET-CT every 6 months during the first year and annual afterwards) performed after the splenectomy. DISCUSSION AND CONCLUSIONS: The value of tumor markers and radiology for diagnosis of splenic cysts is put into question. Only 60 cases of Fibrin-associated LBCL (FA-LBCL) have been described in the literature therefore there are no treatment guidelines for them even though surgery together with systemic treatment has been the prevalent route with good results in most cases.
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Quistes , Esplenectomía , Enfermedades del Bazo , Neoplasias del Bazo , Humanos , Esplenectomía/métodos , Adulto , Quistes/cirugía , Quistes/patología , Enfermedades del Bazo/cirugía , Enfermedades del Bazo/patología , Neoplasias del Bazo/cirugía , Neoplasias del Bazo/patología , Neoplasias del Bazo/complicaciones , Masculino , Pronóstico , Laparoscopía/métodos , Linfoma de Células B Grandes Difuso/patología , Linfoma de Células B Grandes Difuso/cirugía , Linfoma de Células B Grandes Difuso/complicaciones , Linfoma de Células B Grandes Difuso/diagnóstico , Linfoma de Células B/cirugía , Linfoma de Células B/patología , Linfoma de Células B/complicaciones , Linfoma de Células B/diagnóstico , Rituximab/administración & dosificación , Rituximab/uso terapéuticoRESUMEN
Arbuscular mycorrhizal fungi (AMF) colonize biochar in soils, yet the processes governing their colonization and growth in biochar are not well characterized. Biochar amendment improves soil health by increasing soil carbon, decreasing bulk density, and improving soil water retention, all of which can increase yield and alleviate environmental stress on crops. Biochar is often applied with nutrient addition, impacting mycorrhizal communities. To understand how mycorrhizas explore soils containing biochar, we buried packets of non-activated biochar in root exclusion mesh bags in contrasting agricultural soils. In this greenhouse experiment, with quinoa (Chenopodium quinoa) as the host plant, we tested impacts of mineral nutrient (as manure and fertilizer) and biochar addition on mycorrhizal colonization of biochar. Paraglomus appeared to dominate the biochar packets, and the community of AMF found in the biochar was a subset (12 of 18) of the virtual taxa detected in soil communities. We saw differences in AMF community composition between soils with different edaphic properties, and while nutrient addition shifted those communities, the shifts were inconsistent between soil types and did not significantly influence the observation that Paraglomus appeared to selectively colonize biochar. This observation may reflect differences in AMF traits, with Paraglomus previously identified only in soils (not in roots) pointing to predominately soil exploratory traits. Conversely, the absence of some AMF from the biochar implies either a reduced tendency to explore soils or an ability to avoid recalcitrant nutrient sources. Our results point to a selective colonization of biochar in agricultural soils.
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Carbón Orgánico , Micorrizas , Microbiología del Suelo , Suelo , Micorrizas/fisiología , Suelo/química , Agricultura/métodos , Chenopodium quinoa , Raíces de Plantas/microbiología , Estiércol/microbiología , Estiércol/análisisRESUMEN
This paper presents the results of a listening experiment designed to assess annoyance and perceived loudness (PL) for several unmanned aircraft system (UAS) operations, with the listener simulated in indoor and outdoor positions. This research investigated (i) how participant responses change depending on UAS operation, (ii) which broadband metrics are most suitable for representing annoyance and PL, (iii) differences in noise level required to result in equal participant responses to different operations, and (iv) which sound quality metrics (SQMs) are significant for UAS noise perception. Results indicate annoyance and PL responses were greatest for landing operations with flyovers being the least annoying or loud. LAeq, LASmax, and loudness (N5) were the strongest predictors in representing annoyance. Offset analysis predicted small differences in annoyance responses between flyovers and other operations, but also indicated that flyovers would require an increase to LASmax of 3.3 to 6.3 dB compared to other operations to achieve equal PL. Loudness was the most significant SQM, with minor contributions from impulsivity for annoyance and PL when outside, and tonality for PL when indoors. These findings contribute to the understanding of UAS noise perception for the development of metrics and assessment methods accounting for the characteristics of UAS operations.
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Aeronaves , Ruido , Humanos , Ruido/efectos adversos , PercepciónRESUMEN
Activated carbon (AC), renowned for its versatile applications in water treatment, air purification, and industrial processes, is a critical component in environmental remediation and resource recovery strategies. This study encompasses the process modeling of AC production using anthracite coal as a precursor, involving multiple activation stages at different operating conditions, coupled with a detailed techno-economic analysis aimed at assessing the operational feasibility and financial viability of the plant. The economic analysis explores the investigation of economic feasibility by performing a detailed cashflow and sensitivity analysis to identify key parameters influencing the plant's economic performance, including raw material and energy prices, operational and process parameters. Capital and operational costs are meticulously evaluated, encompassing raw material acquisition, labor, energy consumption, and equipment investment. Financial metrics like Net Present Value (NPV), Internal Rate of Return (IRR), and payout period (POP) are employed, and the results show that AC selling price, raw material cost and plant capacity are the most influential parameters determining the plant's feasibility. The minimum AC production cost of 1.28 $/kg is obtained, corresponding to coal flow rate of 14,550 kg/h. These findings provide valuable insights for stakeholders, policymakers, and investors seeking to engage in activated carbon production from anthracite.
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Carbón Orgánico , Restauración y Remediación Ambiental , Carbón Mineral , Inversiones en Salud , PlantasRESUMEN
OBJECTIVE: To describe the incidence and predictors of acute limb ischemia (ALI) in patients with acute myocardial infarction (AMI) complicated by cardiogenic shock (CS). METHODS: Patients with index hospitalizations for AMI complicated by cardiogenic shock from 2016 to 2019 in the US National Readmission Database were identified. We evaluated the incidence of ALI and its associated mortality, length of stay, and cost of hospitalization. We used multivariable logistic regression to determine independent predictors of ALI in this population. RESULTS: A total of 84,615 patients had AMI complicated by cardiogenic shock and 1302 (1.54%) developed ALI. The rates of ALI increased from 1.29% in 2016 to 1.66% in 2019 (P ≤ .002). The use of microaxial mechanical circulatory support increased from 2.25% in 2016 to 13.36% in 2019 (P = .0001). The major predictors of ALI included peripheral arterial disease (odds ratio [OR], 7.34; 95% confidence interval [CI], 6.12-8.81), venoarterial extracorporeal membrane oxygenation (OR, 4.40; 95% CI, 3.19-6.07), and microaxial mechanical circulatory support (OR, 3.12; 95% CI, 2.74-3.55). ALI in patients with cardiogenic shock was associated higher mortality (39.20% vs 33.53%; P ≤ .0001). CONCLUSIONS: This nationwide observational study shows that ALI is an important complication of AMI with cardiogenic shock. This complication is associated with higher mortality. In addition to peripheral artery disease, the use of mechanical circulatory devices was associated with significantly higher rates of ALI.
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Corazón Auxiliar , Infarto del Miocardio , Enfermedad Arterial Periférica , Humanos , Choque Cardiogénico , Incidencia , Resultado del Tratamiento , Mortalidad Hospitalaria , Enfermedad Arterial Periférica/complicaciones , Corazón Auxiliar/efectos adversos , Estudios RetrospectivosRESUMEN
RATIONALE: Ca2+-induced Ca2+ release (CICR) in normal hearts requires close approximation of L-type calcium channels (LTCCs) within the transverse tubules (T-tubules) and RyR (ryanodine receptors) within the junctional sarcoplasmic reticulum. CICR is disrupted in cardiac hypertrophy and heart failure, which is associated with loss of T-tubules and disruption of cardiac dyads. In these conditions, LTCCs are redistributed from the T-tubules to disrupt CICR. The molecular mechanism responsible for LTCCs recruitment to and from the T-tubules is not well known. JPH (junctophilin) 2 enables close association between T-tubules and the junctional sarcoplasmic reticulum to ensure efficient CICR. JPH2 has a so-called joining region that is located near domains that interact with T-tubular plasma membrane, where LTCCs are housed. The idea that this joining region directly interacts with LTCCs and contributes to LTCC recruitment to T-tubules is unknown. OBJECTIVE: To determine if the joining region in JPH2 recruits LTCCs to T-tubules through direct molecular interaction in cardiomyocytes to enable efficient CICR. METHODS AND RESULTS: Modified abundance of JPH2 and redistribution of LTCC were studied in left ventricular hypertrophy in vivo and in cultured adult feline and rat ventricular myocytes. Protein-protein interaction studies showed that the joining region in JPH2 interacts with LTCC-α1C subunit and causes LTCCs distribution to the dyads, where they colocalize with RyRs. A JPH2 with induced mutations in the joining region (mutPG1JPH2) caused T-tubule remodeling and dyad loss, showing that an interaction between LTCC and JPH2 is crucial for T-tubule stabilization. mutPG1JPH2 caused asynchronous Ca2+-release with impaired excitation-contraction coupling after ß-adrenergic stimulation. The disturbed Ca2+ regulation in mutPG1JPH2 overexpressing myocytes caused calcium/calmodulin-dependent kinase II activation and altered myocyte bioenergetics. CONCLUSIONS: The interaction between LTCC and the joining region in JPH2 facilitates dyad assembly and maintains normal CICR in cardiomyocytes.
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Canales de Calcio Tipo L/metabolismo , Señalización del Calcio , Calcio/metabolismo , Hipertrofia Ventricular Izquierda/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas Musculares/metabolismo , Miocitos Cardíacos/metabolismo , Animales , Canales de Calcio Tipo L/genética , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/metabolismo , Gatos , Células Cultivadas , Modelos Animales de Enfermedad , Acoplamiento Excitación-Contracción , Humanos , Hipertrofia Ventricular Izquierda/patología , Hipertrofia Ventricular Izquierda/fisiopatología , Cinética , Masculino , Proteínas de la Membrana/genética , Mitocondrias Cardíacas/metabolismo , Mitocondrias Cardíacas/patología , Proteínas Musculares/genética , Mutación , Miocitos Cardíacos/patología , Biogénesis de Organelos , Unión Proteica , Dominios y Motivos de Interacción de Proteínas , Ratas Sprague-Dawley , Canal Liberador de Calcio Receptor de RianodinaRESUMEN
BACKGROUND AND AIMS: Within-population genetic and phenotypic variation play a key role in the development of adaptive responses to environmental change. Between-population variation is also an essential element in assessing the evolutionary potential of species in response to changes in environmental conditions. In this context, common garden experiments are a useful tool to separate the genetic and environmental components of phenotypic variation. We aimed to assess within- and between-population phenotypic variation of Lupinus angustifolius L. in terms of its evolutionary potential to adapt to ongoing climate change. METHODS: We evaluated populations' phenotypic variation of foliar, phenological and reproductive traits with a common garden experiment. Patterns of functional trait variation were assessed with (1) mixed model analyses and coefficients of variation (CVs) with confidence intervals, (2) principal component analyses (PCAs) and (3) correlations between pairs of traits. Analyses were performed at the population level (four populations) and at the latitude level (grouping pairs of populations located in two latitudinal ranges). KEY RESULTS: Phenotypic variation had a significant genetic component associated with a latitudinal pattern. (1) Mixed models found lower specific leaf area, advanced flowering phenology and lower seed production of heavier seeds in southern populations, whereas CV analyses showed lower within-latitude variation especially in phenological and reproductive traits in southern populations. (2) PCAs showed a clearer differentiation of phenotypic variation between latitudes than between populations. (3) Correlation analyses showed a greater number of significant correlations between traits in southern populations (25 vs. 13). CONCLUSIONS: Between-population phenotypic variation was determined by contrasting temperature and drought at different latitude and elevation. Southern populations had differential trait values compatible with adaptations to high temperatures and drought. Moreover, they had lower within-population variation and a greater number of trait correlations probably as a result of these limiting conditions, making them more vulnerable to climate change.
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Lupinus , Lupinus/genética , Fenotipo , Semillas , Hojas de la Planta , ReproducciónRESUMEN
Pyogenic liver abscess (PLA) is a life-threatening infection in both liver transplant (LT) and non-LT patients. Several risk factors, such as benign and malignant hepatopancreatobiliary diseases and colorectal tumors have been associated with PLA in the non-LT population, and hepatic artery stricture/thrombosis, biliary stricture, and hepaticojejunostomy in the LT patients. The objective of this study is to compare the outcomes of patients with PLA in LT and non-LT patients and to determine the risk factors associated with patient survival. From January 2000 to November 2020, a total of 296 adult patients were diagnosed of PLA in our institution, of whom 26 patients had previously undergone liver transplantation (LTA group), whereas 263 patients corresponded to the non-LTA population. Seven patients with PLA who had undergone previous kidney transplantation were excluded from this retrospective study. Twenty-six patients out of 1503 LT developed PLA (incidence of 1.7%). Median age was significantly higher in non-LTA patients (p = .001). No significant differences were observed in therapy. PLA recurrence was significantly higher in LTA than in non-LTA (34.6% vs. 14.8%; p = .008). In-hospital mortality was greater in the LT group than in the non-LT group (19.2% vs. 9.1% p = .10) and was identified in multivariable analysis as a risk factor for mortality (p = .027). Mortality rate during follow-up did not show significant differences between the groups: 34.6% in LTA patients versus 26.2% in non-LTA patients (p = .10). The most common causes of mortality during follow-up were malignancies, Covid-19 infection, and neurologic disease. 1-, 3-, and 5-year actuarial patient survival rates were 87.0%, 64.1%, and 50.4%, respectively, in patients of LTA group, and 84.5%, 66.5%, and 51.0%, respectively, in patients with liver abscesses in non-LTA population (p = .53). In conclusion, LT was a risk factor for in hospital mortality, but not during long-term follow-up.
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COVID-19 , Absceso Piógeno Hepático , Trasplante de Hígado , Adulto , Humanos , Absceso Piógeno Hepático/etiología , Absceso Piógeno Hepático/terapia , Estudios Retrospectivos , Trasplante de Hígado/efectos adversos , Constricción Patológica/etiología , COVID-19/etiología , Factores de RiesgoRESUMEN
BACKGROUND: Percutaneous drainage (PD) and antibiotics are the therapy of choice (non-surgical therapy [non-ST]) for pyogenic liver abscesses (PLA), reserving surgical therapy (ST) for PD failure. The aim of this retrospective study was to identify risk factors that indicate the need for ST. METHODS: We reviewed the medical charts of all of our institution's adult patients with a diagnosis of PLA between January 2000 and November 2020. A series of 296 patients with PLA was divided into two groups according to the therapy used: ST (n = 41 patients) and non-ST (n = 255). A comparison between groups was performed. RESULTS: The overall median age was 68 years. Demographics, clinical history, underlying pathology, and laboratory variables were similar in both groups, except for the duration of PLA symptoms < 10 days and leukocyte count which were significantly higher in the ST group. The in-hospital mortality rate in the ST group was 12.2% vs. 10.2% in the non-ST group (p = 0.783), with biliary sepsis and tumor-related abscesses as the most frequent causes of death. Hospital stay and PLA recurrence were statistically insignificant between groups. One-year actuarial patient survival was 80.2% in the ST group vs. 84.6% in the non-ST (p = 0.625) group. The presence of underlying biliary disease, intra-abdominal tumor, and duration of symptoms for less than 10 days on presentation comprised the risk factors that indicated the need to perform ST. CONCLUSIONS: There is little evidence regarding the decision to perform ST, but according to this study, the presence of underlying biliary disease or an intra-abdominal tumor and the duration of PLA symptoms < 10 days upon presentation are risk factors that should sway the surgeons to perform ST instead of PD.
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Neoplasias Abdominales , Enfermedades de la Vesícula Biliar , Absceso Piógeno Hepático , Anciano , Humanos , Neoplasias Abdominales/complicaciones , Neoplasias Abdominales/tratamiento farmacológico , Antibacterianos/uso terapéutico , Absceso Piógeno Hepático/diagnóstico , Absceso Piógeno Hepático/etiología , Absceso Piógeno Hepático/terapia , Poliésteres , Estudios Retrospectivos , Factores de RiesgoRESUMEN
Melanoma is a cancer that frequently metastasises to the small bowel, but most cases are asymptomatic and are diagnosed postmortem. Therefore, CT and PET CT cannot detect all lesions and conventional endoscopic study only detects 10-20% of lesions. In this study, we present the case of a 68-year-old patient with a history of cutaneous melanoma and a diagnosis of intestinal melanoma. Thanks to capsule endoscopy, two lesions compatible with cutaneous melanoma metastasis to the small bowel were detected, allowing a much more effective surgical planning. Capsule endoscopy is an innovative technique that improves preoperative diagnosis, as it is able to detect bowel segments that cannot be inspected by conventional endoscopy. It also has a better resolution than conventional CT, improving sensitivity in the detection of lesions.
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Endoscopía Capsular , Neoplasias Intestinales , Melanoma , Neoplasias Cutáneas , Humanos , Anciano , Melanoma/diagnóstico por imagen , Melanoma/patología , Endoscopía Capsular/métodos , Neoplasias Cutáneas/patología , Endoscopía Gastrointestinal , Intestino Delgado/patología , Neoplasias Intestinales/diagnóstico por imagen , Neoplasias Intestinales/cirugía , Hemorragia Gastrointestinal/patologíaRESUMEN
BACKGROUND: The usefulness of tracheostomy has been questioned in patients with COVID-19 and prolonged invasive mechanical ventilation (IMV). AIM: To compare the 90-day mortality rate of patients who underwent a tracheostomy due prolonged IMV with those that did not receive this procedure. MATERIAL AND METHODS: We studied a historical cohort of 92 patients with COVID-19 and prolonged IMV (> 10 days). The primary outcome was the 90-day mortality rate. Secondary outcomes included days on IMV, hospital/intensive care unit (ICU) length of stay, frequency of nosocomial infections, and thrombotic complications demonstrated by images. A logistic regression was performed to adjust the effect of tracheostomy by SOFA score and days on IMV. RESULTS: Forty six patients aged 54 to 66 years (72% males) underwent tracheostomy. They had a median of two comorbidities, and received the procedure after a median of 20.5 days on IMV (interquartile range: 17-26). 90-day mortality was lower in patients who were tracheostomized than in the control group (6.5% vs. 32.6%, p-value < 0.01). However, after controlling for confounding factors, no differences were found in mortality between both groups (relative risk = 0.303, p-value = 0.233). Healthcare-associated infections and hospital/ICU length of stay were higher in patients with tracheostomy than in controls. Thrombotic complications occurred in 42.4% of the patients, without differences between both groups. No cases of COVID-19 were registered in the healthcare personnel who performed tracheostomies. CONCLUSIONS: In patients with COVID-19 undergoing prolonged IMV, performing a tracheostomy is not associated with excess mortality, and it is a safe procedure for healthcare personnel.
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COVID-19 , Respiración Artificial , Masculino , Humanos , Femenino , Traqueostomía/efectos adversos , Unidades de Cuidados Intensivos , Mortalidad Hospitalaria , Estudios RetrospectivosRESUMEN
We tested 294 domestic pet dogs in Mexico for neutralizing antibodies for mosquito-borne flaviviruses. We found high (42.6%) exposure to West Nile virus in Reynosa (northern Mexico) and low (1.2%) exposure in Tuxtla Gutierrez (southern Mexico) but very limited exposure to Aedes-borne flaviviruses. Domestic dogs may be useful sentinels for West Nile virus.
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Aedes , Culicidae , Flavivirus , Fiebre del Nilo Occidental , Virus del Nilo Occidental , Animales , Anticuerpos Neutralizantes , Perros , México/epidemiología , Fiebre del Nilo Occidental/epidemiología , Fiebre del Nilo Occidental/veterinariaRESUMEN
Environmental variation within a species' range can create contrasting selective pressures, leading to divergent selection and novel adaptations. The conservation value of populations inhabiting environmentally marginal areas remains in debate and is closely related to the adaptive potential in changing environments. Strong selection caused by stressful conditions may generate novel adaptations, conferring these populations distinct evolutionary potential and high conservation value under climate change. On the other hand, environmentally marginal populations may be genetically depauperate, with little potential for new adaptations to emerge. Here, we explored the use of ecological niche models (ENMs) linked with common garden experiments to predict and test for genetically determined phenotypic differentiation related to contrasting environmental conditions. To do so, we built an ENM for the alpine plant Silene ciliata in central Spain and conducted common garden experiments, assessing flowering phenology changes and differences in leaf cell resistance to extreme temperatures. The suitability patterns and response curves of the ENM led to the predictions that: (1) the environmentally marginal populations experiencing less snowpack and higher minimum temperatures would have delayed flowering to avoid risks of late-spring frosts and (2) those with higher minimum temperatures and greater potential evapotranspiration would show enhanced cell resistance to high temperatures to deal with physiological stress related to desiccation and heat. The common garden experiments revealed the expected genetically based phenotypic differentiation in flowering phenology. In contrast, they did not show the expected differentiation for cell resistance, but these latter experiments had high variance and hence lower statistical power. The results highlight ENMs as useful tools to identify contrasting putative selective pressures across species ranges. Linking ENMs with common garden experiments provides a theoretically justified and practical way to study adaptive processes, including insights regarding the conservation value of populations inhabiting environmentally marginal areas under ongoing climate change.
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Adaptación Fisiológica , Cambio Climático , Aclimatación , Adaptación Fisiológica/fisiología , Evolución Biológica , EcosistemaRESUMEN
KEY MESSAGE: The gene underlying the melon fruit shape QTL fsqs8.1 is a member of the Ovate Family Proteins. Variation in fruit morphology is caused by changes in gene expression likely due to a cryptic structural variation in this locus. Melon cultivars have a wide range of fruit morphologies. Quantitative trait loci (QTL) have been identified underlying such diversity. This research focuses on the fruit shape QTL fsqs8.1, previously detected in a cross between the accession PI 124112 (CALC, producing elongated fruit) and the cultivar 'Piel de Sapo' (PS, producing oval fruit). The CALC fsqs8.1 allele induced round fruit shape, being responsible for the transgressive segregation for this trait observed in that population. In fact, the introgression line CALC8-1, carrying the fsqs8.1 locus from CALC into the PS genetic background, produced perfect round fruit. Following a map-based cloning approach, we found that the gene underlying fsqs8.1 is a member of the Ovate Family Proteins (OFP), CmOFP13, likely a homologue of AtOFP1 and SlOFP20 from Arabidopsis thaliana and tomato, respectively. The induction of the round shape was due to the higher expression of the CALC allele at the early ovary development stage. The fsqs8.1 locus showed an important structural variation, being CmOFP13 surrounded by two deletions in the CALC genome. The deletions are present at very low frequency in melon germplasm. Deletions and single nucleotide polymorphisms in the fsqs8.1 locus could not be not associated with variation in fruit shape among different melon accessions, what indicates that other genetic factors should be involved to induce the CALC fsqs8.1 allele effects. Therefore, fsqs8.1 is an example of a cryptic variation that alters gene expression, likely due to structural variation, resulting in phenotypic changes in melon fruit morphology.
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Cucurbitaceae , Solanum lycopersicum , Mapeo Cromosómico , Cucurbitaceae/genética , Frutas , Solanum lycopersicum/genética , Sitios de Carácter CuantitativoRESUMEN
INTRODUCTION: Satisfactory outcomes in a series of liver transplantations (LT) with octogenarian liver grafts have been reported, as well as several cases of LT using nonagenarian liver grafts with short follow-up. METHODS: From October 2013 to December 2019, we performed 426 LT. Six LTs used nonagenarian livers (case group) and 49 used octogenarian livers (control group). A comparative analysis was performed between groups. Median donor age was significantly higher in the nonagenarian group than in the octogenarian group (90.6 years versus 83.4 years; (P < .001). There was a significant difference in LT indications (P = .026) between the groups, but not in perioperative recipient variables, morbidity, or mortality. The 1-, 3-, and 5-year patient survival rates were 67.7% in the recipients of nonagenarian livers and 85.7%, 78.0%, and 74.4%, respectively, in the recipients of octogenarian livers (P = .631). The 1-, 3-, and 5-year graft survival rates were 66.7% in the recipients of nonagenarian livers and 81.3%, 73.8%, and 70.3%, respectively, in the recipients of octogenarian livers (P = .745). CONCLUSIONS: The results of LT with nonagenarian liver grafts are not significantly different from those obtained with octogenarian donors, taking into consideration the small sample size and careful selection of donors and adequate donor-recipient matching.
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Trasplante de Hígado , Factores de Edad , Anciano de 80 o más Años , Supervivencia de Injerto , Humanos , Hígado , Nonagenarios , Estudios Retrospectivos , Donantes de Tejidos , Resultado del TratamientoRESUMEN
Difficulty in obtaining adequate abdominal wall closure due to loss of the abdominal domain is a frequent complication of multivisceral, isolated intestinal transplantation and in some cases of liver transplantation. Various methods for primary closure have been proposed, including the use of synthetic and biological meshes, as well as full-thickness abdominal wall and non-vascularized rectus fascia grafts. We describe a novel technique for abdominal wall procurement in which the graft is perfused synchronously with the abdominal organs and can be transplanted as a full-thickness wall or as a non-vascularized rectus fascia graft. We performed six transplants of non-vascularized rectus fascia in three intestinal transplants, one multivisceral transplant, and two liver transplants. The size of the covered abdominal wall defects ranged from 17 cm × 7 cm to 25 cm × 20 cm. Only one patient developed graft infection secondary to enterocutaneous fistula requiring surgical correction and removal of the fascia graft. This patient, as well as two other patients, died due to sepsis. Our procurement technique allows removal of the rectus fascia graft to cover the abdominal wall defect, providing a feasible solution for treatment of abdominal wall defects in recipients after abdominal organ transplantation.
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Pared Abdominal , Trasplante de Hígado , Trasplante de Órganos , Músculos Abdominales , Pared Abdominal/cirugía , Fascia/trasplante , Humanos , Trasplante de Hígado/métodosRESUMEN
The authors did not receive any funding for this work.