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1.
PLoS Biol ; 22(1): e3002444, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38261631

RESUMEN

Plants, animals, and fungi display a rich tapestry of colors. Animals, in particular, use colors in dynamic displays performed in spatially complex environments. Although current approaches for studying colors are objective and repeatable, they miss the temporal variation of color signals entirely. Here, we introduce hardware and software that provide ecologists and filmmakers the ability to accurately record animal-perceived colors in motion. Specifically, our Python codes transform photos or videos into perceivable units (quantum catches) for animals of known photoreceptor sensitivity. The plans and codes necessary for end-users to capture animal-view videos are all open source and publicly available to encourage continual community development. The camera system and the associated software package will allow ecologists to investigate how animals use colors in dynamic behavioral displays, the ways natural illumination alters perceived colors, and other questions that remained unaddressed until now due to a lack of suitable tools. Finally, it provides scientists and filmmakers with a new, empirically grounded approach for depicting the perceptual worlds of nonhuman animals.


Asunto(s)
Iluminación , Programas Informáticos , Animales , Movimiento (Física)
2.
Biol Lett ; 19(11): 20230384, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-38016645

RESUMEN

Avian brood parasitism is a model system for understanding coevolutionary arms races, and the great reed warbler (Acrocephalus arundinaceus, hereafter 'warbler') and its parasite the common cuckoo (Cuculus canorus, hereafter 'cuckoo') are prime examples of this coevolutionary struggle. Here, warblers select for egg colour mimicry by rejecting poorly matched cuckoo eggs. Contrary to long-held assumptions, recent work showed that warblers tend to reject lighter and browner eggs but tended to accept darker and bluer eggs rather than basing rejection decisions solely on perceived colour differences (i.e. the degree of mimicry). This counterintuitive, colour-biased rejection behaviour would select for bluer and darker cuckoo eggs, but would only be adaptive if cuckoos were consistently lighter and browner than warbler eggs. Therefore, we tested whether warbler eggs were consistently bluer and darker than cuckoo eggs. To do so, we re-analysed eggshell reflectance spectra of warblers and the cuckoos that parasitized them in the Czech Republic. As expected, we found that warbler eggs were significantly bluer and darker than the cuckoo eggs at the population level. Thus, we demonstrate imperfect mimicry in a long-coevolved cuckoo host-race and provide insights for exploring the coevolutionary interactions among hosts and their brood parasites.


Asunto(s)
Passeriformes , Pájaros Cantores , Animales , Cáscara de Huevo , Color , Comportamiento de Nidificación , Interacciones Huésped-Parásitos
3.
Vox Sang ; 118(9): 783-789, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37533171

RESUMEN

BACKGROUND AND OBJECTIVES: Bone marrow (BM) harvesting is one of the essential sources of stem cells for haematopoietic stem cell transplantation. In 2019, commercial BM collection kits became unavailable in Europe. Consequently, we created an in-house BM collection kit as an alternative. MATERIALS AND METHODS: We compared two groups of BM collections. The first collections were taken using an in-house kit from June 2022 through February 2023 and the second with a commercial kit from February 2021 through May 2022. These all took place at seven collection centres (CC). We analysed the harvest quality (cell blood count, CD34+ cells, viability, potency and sterility), the incidents occurring with each kit and the time to neutrophil and platelet engraftment in recipients. RESULTS: A total of 23 donors underwent BM harvesting with the in-house kit and 23 with the commercial one. Both cohorts were comparable regarding donor characteristics, CC and time to procedure. No statistical differences were found in harvest quality between the in-house and commercial kits. A new transfusion set was required in three BM harvests (13%) with the in-house kit because of filter clogging. The median time to neutrophil and platelet engraftment was 21 days for both cohorts and 29 days (in-house) and 33 days (commercial), p = 0.284, respectively. CONCLUSION: The in-house BM collection kit offers a real approach to solve the diminished supply of commercial kits. A higher risk of filter clogging was observed compared with commercial kits due to the lack of 850 and 500 µm filters.


Asunto(s)
Trasplante de Médula Ósea , Trasplante de Células Madre Hematopoyéticas , Humanos , Trasplante de Médula Ósea/métodos , Médula Ósea , Trasplante Homólogo , Donantes de Tejidos
4.
J Exp Biol ; 226(14)2023 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-37357579

RESUMEN

Hosts of obligate avian brood parasites often evolve defense mechanisms to avoid rearing unrelated young. One common defense is egg rejection, for which hosts often rely on eggshell color. Most research has assumed that hosts respond to perceived color differences between their own eggs and parasite eggs regardless of the particular color; however, recent experiments have found that many hosts respond more strongly to brown foreign eggs than to equally dissimilar blue eggs. Yet, none of these prior studies tested a brown-egg-laying species and, with only one exception, all were conducted in open nests where light levels are considered sufficient for effective color-based egg discrimination. Here, we explored how two cavity-nesting hosts of the parasitic brown-headed cowbird (Molothrus ater) - the blue-egg-laying eastern bluebird (Sialia sialis) and the brown-egg-laying house wren (Troglodytes aedon) - respond to experimental eggs painted six distinct colors ranging from blue to brown. Rejection responses of both hosts were best predicted by perceived differences in color between the model egg and their own eggs. Specifically, we found that house wrens preferentially rejected eggs bluer than their own eggs. However, although we found that bluebirds relied on perceived differences in color for their egg rejection decisions, further tests are needed to determine whether they preferentially rejected brown eggs or simply responded to absolute perceived differences in color. These findings demonstrate that these cavity-nesting birds treat perceived color differences in distinct ways, which has important implications on the coevolutionary arms races and the interpretation of avian-perceived color differences.


Asunto(s)
Parásitos , Passeriformes , Pájaros Cantores , Animales , Comportamiento de Nidificación/fisiología , Passeriformes/fisiología , Pájaros Cantores/fisiología , Huevos , Óvulo , Interacciones Huésped-Parásitos
5.
Transplant Proc ; 54(9): 2414-2418, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36333253

RESUMEN

BACKGROUND: The assessment of class II eplet mismatch load is useful to determine the risk of chronic rejection in solid organ transplantation. However, high-resolution (2-field) HLA typing is mandatory to accurately define eplet mismatches. The imputation of the most frequent allele has been used in retrospective studies. Here, we sought to investigate the concordant of antibody-verified (AbV) eplet load in different class II alelles between real 2-field HLA typing and HLA imputed by most frequent allele in a large White cohort. MATERIALS AND METHODS: The allelic frequency of the different HLA class II loci was calculated using a database of high-resolution typing of 23,628 voluntary Spanish bone marrow donors obtained from the Spanish Registry of Bone Marrow Donors, managed by the Josep Carreras Foundation. The AbV eplet count in the different class II alleles was performed using the HLA-Matchmaker v3.1 algorithm. RESULTS: The probability of imputing the correct allele compared to the most frequent for DRB1 and DQB1 loci was 69.3% and 53.0%, respectively. However, studying the less frequent alleles, the same AbV eplet load was observed in 82.22% and 76.15%, respectively. CONCLUSIONS: Our data show that despite the potential error in the imputation of class II HLA typing, the number of AbV eplets is not significantly over- or underestimated in our population. Until high-resolution typing is widely established for solid organ transplantation, retrospective studies of AbV eplet mismatch load with imputed high-resolution types provide an acceptable outcome in White people.


Asunto(s)
Rechazo de Injerto , Donantes de Tejidos , Humanos , Rechazo de Injerto/epidemiología , Estudios Retrospectivos , Prueba de Histocompatibilidad , Anticuerpos , Alelos , Pueblo Europeo , Antígenos HLA/genética
6.
Bone Marrow Transplant ; 57(10): 1531-1538, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35804055

RESUMEN

Cryopreservation was recommended to ensure continuity in allogeneic hematopoietic progenitor cells (HPC) transplantation during the COVID-19 pandemic. Several groups have shown no impact on clinical outcomes for patients who underwent HPC transplantation with cryopreserved products during the first months of this pandemic. However, concerns about quality control attributes after cryopreservation have been raised. We investigated, in 155 allogeneic peripheral blood cryopreserved HPC, leukocytapheresis characteristics influencing viable CD34+ and CD3+ cells, and CFU-GM recoveries after thawing. Collection characteristics such as volume, nucleated cells (NC)/mL and hematocrit correlated with viable CD34+ and CD3+ cells recoveries after thawing in univariate analysis but only CD3+ cells remained statistically significant in multivariate analysis (r2 = 0.376; P = < 0.001). Additionally, transit time also showed correlation with viable CD34+ (r2 = 0.186), CD3+ (r2 = 0.376) and CFU-GM recoveries (r2 = 0.212) in multivariate analysis. Thus, diluting leukocytapheresis below 200 × 106 NC/mL, avoiding red cells contamination above 2%, cryopreserving below 250 × 106 NC/mL and minimizing transit time below 36 h, prevented poor viable CD34+ and CD3+ cells, and CFU-GM recoveries. In summary, optimizing leukocytapheresis practices and minimizing transportation time may better preserve the quality attributes of HPC when cryopreservation is indicated.


Asunto(s)
COVID-19 , Trasplante de Células Madre Hematopoyéticas , Antígenos CD34/análisis , Supervivencia Celular , Criopreservación , Células Madre Hematopoyéticas , Humanos , Leucaféresis , Pandemias
8.
Rev. colomb. cardiol ; 29(2): 235-239, ene.-abr. 2022. tab, graf
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1376884

RESUMEN

Resumen Se presenta el caso de un paciente de 68 años con aleteo auricular perimitral recurrente a terapia antiarrítmica en el seguimiento de ablación de venas pulmonares por fibrilación auricular. En este caso no se logra el control de la arritmia a pesar de una aproximación usual; se aplica radiofrecuencia endoepicárdica del istmo mitral. En vista de lo anterior, se decide realizar alcoholización de la vena de Marshall; una técnica rápida, útil y efectiva en el control de esta arritmia. A continuación, se describe el paso a paso con el objetivo de familiarizar a los cardiólogos intervencionistas con esta técnica. A la fecha, el paciente se encuentra en ritmo sinusal y sin recurrencia de la arritmia en el seguimiento.


Abstract The case of a 68-year-old patient with recurrent perimitral atrial flutter to anti-arrhythmic therapy in the follow-up of pulmonary vein ablation due to atrial fibrillation is presented. In our case, arrhythmia control is not achieved despite a usual approach; Endo-epicardial radiofrequency application at the mitral isthmus level. Given the above, it was decided to alcoholize Marshall’s vein; a fast, useful and effective technique in the control of this arrhythmia. Here is a step-by-step guide to familiarize interventional cardiologists with this technique. The patient is in sinus rhythm and without recurrence of the arrhythmia at follow-up.

9.
Bone Marrow Transplant ; 56(10): 2489-2496, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34127808

RESUMEN

Cryopreservation was recommended to ensure continuity of unrelated donor (UD) hematopoietic stem cell transplantation (HSCT) during COVID-19 pandemic. However, its impact on clinical outcomes and feasibility was not well known. We compared 32 patients who underwent UD HSCT using cryopreserved peripheral blood stem cells (PBSC) during the COVID-19 pandemic with 32 patients who underwent UD HSCT using fresh PBSC in the previous period. Median neutrophil engraftment was 17.5 and 17.0 days with cryopreserved and fresh grafts, respectively. Non-significant delays were found in platelet recovery days (25.5 versus 19.0; P = 0.192) and full donor chimerism days (35.0 and 31.5; P = 0.872) using cryopreserved PBSC. The rate of acute graft-versus-host disease at 100 days was 41% (95% CI [21-55%]) in cryopreserved group versus 31% (95% CI [13-46%]) in fresh group (P = 0.380). One-hundred days progression-relapse free survival and overall survival did not differ significantly. During COVID-19 pandemic, six frozen UD donations were not transfused and logistical and clinical issues regarding cryopreservation procedure, packaging, and transporting appeared. In summary, UD HSCT with cryopreserved PBSC was safe during this challenging time. More efforts are needed to ensure that all frozen grafts are transplanted and cryopreservation requirements are harmonized.


Asunto(s)
COVID-19 , Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas , Criopreservación , Células Madre Hematopoyéticas , Humanos , Pandemias , SARS-CoV-2 , Donante no Emparentado
10.
Stem Cell Res Ther ; 12(1): 233, 2021 04 13.
Artículo en Inglés | MEDLINE | ID: mdl-33849662

RESUMEN

BACKGROUND: iPSC (induced pluripotent stem cells) banks of iPSC lines with homozygous HLA (human leukocyte antigen) haplotypes (haplobanks) are proposed as an affordable and off-the-shelf approach to allogeneic transplantation of iPSC derived cell therapies. Cord blood banks offer an extensive source of HLA-typed cells suitable for reprogramming to iPSC. Several initiatives worldwide have been undertaken to create national and international iPSC haplobanks that match a significant part of a population. METHODS: To create an iPSC haplobank that serves the Spanish population (IPS-PANIA), we have searched the Spanish Bone Marrow Donor Registry (REDMO) to identify the most frequently estimated haplotypes. From the top ten donors identified, we estimated the population coverage using the criteria of zero mismatches in HLA-A, HLA-B, and HLA-DRB1 with different stringencies: high resolution, low resolution, and beneficial mismatch. RESULTS: We have calculated that ten cord blood units from homozygous donors stored at the Spanish cord blood banks can provide HLA-A, HLA-B, and HLA-DRB1 matching for 28.23% of the population. CONCLUSION: We confirm the feasibility of using banked cord blood units to create an iPSC haplobank that will cover a significant percentage of the Spanish and international population for future advanced therapy replacement strategies.


Asunto(s)
Células Madre Pluripotentes Inducidas , Bancos de Sangre , Antígenos HLA/genética , Haplotipos , Humanos , Estudios Prospectivos , Donantes de Tejidos
11.
BMJ Open Sport Exerc Med ; 4(1): e000351, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29955376

RESUMEN

BACKGROUND: Dysnatremia has been associated with sports activity, especially long-distance running and endurance sports. High fluid intake is associated with hyponatremia. This study aims to evaluate dysnatremia and risk factors in half-marathon runners under warm and humid environmental conditions. METHODS: A cross-sectional study was performed among randomly selected runners in the 2017 Cali half marathon. Runners on diuretic therapy or with a known history of kidney disease were excluded. Participants went through a 2-day assessment. Previous medical history, training history, body mass index and running history were determined in the first assessment. Symptoms of dysnatremia and level of fluid consumption during the race were registered during the second assessment and post-run blood sampling for serum [Na+] was also undertaken. RESULTS: 130 runners were included in the study. The complete 2-day assessment was performed on 81 participants (62%) that were included in the final analysis. No cases of hyponatremia were found; instead, there were six cases of asymptomatic hypernatremia (7.4%). This hypernatremia had a statistically significant association with lower frequency (p=0.01) and volume of fluid intake during the race (water: p=0.02, Gatorade: p=0.04). CONCLUSION: Hyponatremia has been associated with high fluid intake in races performed under cool weather, such as the Boston Marathon during spring. In contrast, hypernatremia was found in a half marathon in warm and humid weather, which was associated with lower volume and frequency of fluid intake, suggesting that under warm and humid conditions, a median fluid intake of 900 mL during the race could prevent this event.

12.
Rev. colomb. anestesiol ; 44(4): 324-329, Oct.-Dec. 2016.
Artículo en Inglés | LILACS, COLNAL | ID: biblio-830273

RESUMEN

This reflection article provides an overview of the historical development of the term "euthanasia". It is postulated that the distortion of the term "euthanasia" has hindered the debate around it, so it is imperative to establish the distinction between and other aspects of end of life. Issues associated with palliative care and euthanasia in Colombia are analysed, and some opinions and proposals are presented.


Este artículo de reflexión revisa el desarrollo histórico del término eutanasia. Se postula que desnaturalizarlo ha dificultado el debate y que debe diferenciarse de otros aspectos del final de la vida. Se hace un análisis de la problemática de los cuidados paliativos y la eutanasia en Colombia. Al respecto, se presentan algunas opiniones y propuestas.


Asunto(s)
Humanos
13.
Rev. colomb. anestesiol ; 40(1): 79-81, ene.-mar. 2012.
Artículo en Español | LILACS, COLNAL | ID: lil-650043

RESUMEN

Actualmente el remifentanil es el medicamento de elección en las pacientes candidatas para analgesia intravenosa durante el trabajo de parto; sin embargo, en algunas parturientas no se consigue un adecuado control del dolor con el uso de este opioide. El presente artículo resume dos casos donde la dexmedetomidina se utiliza como coadyuvante en la analgesia intravenosa con remifentanil, con buenos resultados.


At present, remifentanil is the first choice in obstetrical patients who are candidates for intravenous analgesia during labor, although in some cases, the use of this opioid does not provide adequate pain control. This article summarizes two cases where dexmedetomidine was used successfully as an analgesic adjunct to intravenous remifentanil during labor.


Asunto(s)
Humanos
14.
Histopathology ; 54(4): 478-85, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19309400

RESUMEN

AIMS: In T cells, protein kinase C (PKC) theta plays a major role in T-cell receptor (TCR)-mediated activation of a novel nuclear factor (NF)-kappaB pathway that involves phosphorylation of p65 at serine 536 (Pp65(Ser536)). Bcl-10 acts along the same pathway downstream of PKC theta to activate NF-kappaB. The aim was to investigate the relationship between the expression of PKC theta, Bcl-10 and P-p65(Ser536) proteins and their prognostic significance in peripheral T-cell lymphomas (PTCLs). METHODS AND RESULTS: Paraffin-embedded tissues from 30 patients with PTCLs treated with curative intention were evaluated retrospectively. Expression of PKC theta, Bcl-10 and P-p65(Ser536) proteins was assessed using immunohistochemistry. Expression of PKC theta was detected in 22 of 30 cases (73%), Bcl-10 in 20 of 30 (67%) and P-p65(Ser536) in 21 of 30 (70%). Bcl-10+ tumours were associated with PKC theta (18 of 22) (P < 0.0001) and Pp65Ser536 (19 of 21) expression (P < 0.0001). Patients with Bcl-10+ or P-p65(Ser536+) tumours fared better, with a 5-year overall survival of 48 and 45%, respectively, versus 0% for negative tumours (P = 0.029 and P = 0.04, respectively). CONCLUSIONS: Bcl-10 is expressed in PTCLs, correlates with PKC theta and Pp65(Ser536) expression and seems to be associated with better survival.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Biomarcadores de Tumor/metabolismo , Linfoma de Células T Periférico/metabolismo , Linfoma de Células T Periférico/patología , Factor de Transcripción ReIA/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Proteína 10 de la LLC-Linfoma de Células B , Femenino , Humanos , Inmunohistoquímica , Isoenzimas/metabolismo , Masculino , Persona de Mediana Edad , Fosforilación , Pronóstico , Proteína Quinasa C/metabolismo , Proteína Quinasa C-theta , Estudios Retrospectivos , Serina/química , Tasa de Supervivencia , Análisis de Matrices Tisulares , Factor de Transcripción ReIA/química , Adulto Joven
15.
Rev. colomb. anestesiol ; 36(4): 304-307, dic. 2008. ilus
Artículo en Español | LILACS, COLNAL | ID: lil-636008

RESUMEN

Presentamos el caso de un niño con síndrome de Freeman-Sheldon programado para la correccióc quirúrgica de su microstomia. El niño presentabn la característica de "cara de silvador"y deformidades de artrogríposis en manos y pies. Se expone el manejo anestésico y de la vía aéred.


We describe e case of a child with typical clinicalfeaturea of Freeman-Sheldon syndrome (FSS) presentedfor elective surgical correction of microstomia. The anaesthetic cnd airtuay problems encountered erediscussed.


Asunto(s)
Humanos
16.
Rev. colomb. anestesiol ; 34(4): 277-282, sept.-dic. 2006. ilus
Artículo en Español | LILACS | ID: lil-456748

RESUMEN

El AIRTRAQ® es un dispositivo óptico de intubación orotraqueal, de uso único, que permite una completa visualización d la glotis sin requerir la hiperextensión cervical. Presentamos 2 casos de pacientes con sospecha de trauma cervical en los que se utiliza este dispositivo con diferentes resultados y se discute el manejo de la vía aérea difícil anticipada en este contexto...


Asunto(s)
Intubación
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