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1.
Nature ; 630(8017): 671-676, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38867039

RESUMEN

The subpectoral diverticulum (SPD) is an extension of the respiratory system in birds that is located between the primary muscles responsible for flapping the wing1,2. Here we survey the pulmonary apparatus in 68 avian species, and show that the SPD was present in virtually all of the soaring taxa investigated but absent in non-soarers. We find that this structure evolved independently with soaring flight at least seven times, which indicates that the diverticulum might have a functional and adaptive relationship with this flight style. Using the soaring hawks Buteo jamaicensis and Buteo swainsoni as models, we show that the SPD is not integral for ventilation, that an inflated SPD can increase the moment arm of cranial parts of the pectoralis, and that pectoralis muscle fascicles are significantly shorter in soaring hawks than in non-soaring birds. This coupling of an SPD-mediated increase in pectoralis leverage with force-specialized muscle architecture produces a pneumatic system that is adapted for the isometric contractile conditions expected in soaring flight. The discovery of a mechanical role for the respiratory system in avian locomotion underscores the functional complexity and heterogeneity of this organ system, and suggests that pulmonary diverticula are likely to have other undiscovered secondary functions. These data provide a mechanistic explanation for the repeated appearance of the SPD in soaring lineages and show that the respiratory system can be co-opted to provide biomechanical solutions to the challenges of flight and thereby influence the evolution of avian volancy.


Asunto(s)
Vuelo Animal , Animales , Vuelo Animal/fisiología , Músculos Pectorales/fisiología , Alas de Animales/fisiología , Alas de Animales/anatomía & histología , Pulmón/fisiología , Aves/fisiología , Halcones/fisiología , Sistema Respiratorio/anatomía & histología , Fenómenos Biomecánicos , Evolución Biológica , Modelos Biológicos
2.
Dev Dyn ; 251(9): 1576-1612, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-34927301

RESUMEN

BACKGROUND: Squamate reptiles (lizards, snakes, and amphisbaenians) exhibit incredible diversity in their locomotion, behavior, morphology, and ecological breadth. Although they often are used as models of locomotor diversity, surprisingly little attention has been given to muscle development in squamate reptiles. In fact, the most detailed examination was conducted almost 80 years ago and solely focused on the proximal limb regions. Herein, we present forelimb and hindlimb muscle morphogenesis data for three lizard species with different locomotion and feeding strategies: the desert grassland whiptail lizard, the central bearded dragon, and the veiled chameleon. This study fills critical gaps in our understanding of muscle morphogenesis in squamate reptiles and presents a comparative and temporospatial analysis of muscle development. RESULTS: Our results reveal a conserved pattern of early muscle development among lizards with different adult morphologies and ecologies. The variations that exist are concentrated in distal regions, particularly the specialized autopodia of chameleons, where differentiation of muscles associated with the digits is delayed. CONCLUSIONS: The chameleon autopod provides an example of major evolutionary modifications to the skeleton with only minor disruption of the conserved order and pattern of limb muscle development. This robustness of muscle patterning facilitates the evolution of extreme yet functional phenotypes.


Asunto(s)
Lagartos , Animales , Evolución Biológica , Extremidades , Miembro Anterior/anatomía & histología , Miembro Anterior/fisiología , Lagartos/genética , Filogenia , Serpientes
3.
Medicina (Kaunas) ; 59(10)2023 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-37893470

RESUMEN

The RANK-RANKL-OPG system is a complex signaling pathway that plays a critical role in bone metabolism, mammary epithelial cell development, immune function, and cancer. RANKL is a ligand that binds to RANK, a receptor expressed on osteoclasts, dendritic cells, T cells, and other cells. RANKL signaling promotes osteoclast differentiation and activation, which leads to bone resorption. OPG is a decoy receptor that binds to RANKL and inhibits its signaling. In cancer cells, RANKL expression is often increased, which can lead to increased bone resorption and the development of bone metastases. RANKL-neutralizing antibodies, such as denosumab, have been shown to be effective in the treatment of skeletal-related events, including osteoporosis or bone metastases, and cancer. This review will provide a comprehensive overview of the functions of the RANK-RANKL-OPG system in bone metabolism, mammary epithelial cells, immune function, and cancer, together with the potential therapeutic implications of the RANK-RANKL pathway for cancer management.


Asunto(s)
Neoplasias Óseas , Resorción Ósea , Humanos , Receptor Activador del Factor Nuclear kappa-B/metabolismo , Osteoprotegerina , Ligando RANK , Osteoclastos , Neoplasias Óseas/secundario , Resorción Ósea/metabolismo , Homeostasis
4.
Dev Dyn ; 248(8): 709-727, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30980777

RESUMEN

Neural crest cells comprise a migratory progenitor cell population that differentiate into cell types such as neurons and glia of the peripheral nervous system, pigment cells, hormone secreting cells in glands, and skeletal and connective tissue in the head, thus making important contributions to most tissues and organs throughout the vertebrate body. The evolutionary appearance of neural crest cells is considered synonymous with the origin of vertebrates and their subsequent diversification and radiation. While the comparative biology of neural crest cells has been studied for a century and a half beginning with their discovery by Wilhelm His in 1868, most of our understanding of their development and function has come from a small number of species. Thus, critical gaps exist in our understanding of how neural crest cells mediate evolution and development. This is particularly true with respect to squamate reptiles (lizards, snakes, amphisbaenians), which account for approximately one-third of all living tetrapods. Here, we present veiled chameleons (Chamaeleo calyptratus) as a model system for studying neural crest cell development in squamates. Chameleons exhibit various morphological specializations associated with an arboreal lifestyle that may have been facilitated through neural crest cells acting as a conduit for evolutionary change.


Asunto(s)
Lagartos/genética , Cresta Neural/citología , Filogenia , Animales , Evolución Biológica , Diferenciación Celular , Movimiento Celular
5.
Dev Dyn ; 248(8): 702-708, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30839129

RESUMEN

PURPOSE: The veiled chameleon (Chamaeleo calyptratus) is an emerging model system for studying functional morphology and evolutionary developmental biology (evo-devo). Chameleons possess body plans that are highly adapted to an arboreal life style, featuring laterally compressed bodies, split hands/ft for grasping, a projectile tongue, turreted independently moving eyes, and a prehensile tail. Despite being one of the most phenotypically divergent clades of tetrapods, genomic resources for chameleons are severely lacking. METHODS: To address this lack of resources, we used RNAseq to generate 288 million raw Illumina sequence reads from four adult tissues (male and female eyes and gonads) and whole embryos at three distinct developmental stages. We used these data to assemble a largely complete de novo transcriptome consisting of only 82 952 transcripts. In addition, a majority of assembled transcripts (67%) were successfully annotated. RESULTS: We then demonstrated the utility of these data in the context of studying visual system evolution by examining the content of veiled chameleon opsin genes to show that chameleons possess all five ancestral tetrapod opsins. CONCLUSION: We present this de novo, annotated, multi-tissue transcriptome assembly for the Veiled Chameleon, Chamaeleo calyptratus, as a resource to address a range of evolutionary and developmental questions. The associated raw reads and final annotated transcriptome assembly are freely available for use on NCBI and Figshare, respectively.


Asunto(s)
Evolución Biológica , Lagartos/genética , Transcriptoma/genética , Animales , Biología Evolutiva , Ojo/crecimiento & desarrollo , Femenino , Gónadas/crecimiento & desarrollo , Masculino , Anotación de Secuencia Molecular , Opsinas/genética , Vertebrados
6.
Rep Pract Oncol Radiother ; 24(2): 227-232, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30858766

RESUMEN

AIM: To assess the performance of the monitor unit (MU) Objective tool in Eclipse treatment planning system (TPS) utilizing volumetric modulated arc therapy (VMAT) for rectal cancer. BACKGROUND: Eclipse VMAT planning module includes a tool to control the number of MUs delivered: the MU Objective tool. This tool could be utilized to reduce the total number of MUs in rectal cancer treatments. MATERIALS AND METHODS: 20 rectal cancer patients were retrospectively studied using VMAT and the MU Objective tool. The baseline plan for each patient was selected as the one with no usage of the MU Objective tool. The number of MUs of this plan was set to be the reference number of MUs (MUref). Five plans were re-optimized for each patient only varying the Max MU parameter. The selected values were 30%, 60%, 90%, 120% and 150% of MUref for each patient. Differences with respect to the baseline plan were evaluated regarding MU number and parameters for PTVs coverage evaluation, PTVs homogeneity and OARs doses assessment. A two-tailed, paired-samples t-test was used to quantify these differences. RESULTS: Average relative differences in MU number obtained was 10% for Max MU values of 30% and 60% of MUref, respectively (p < 0.03). PTVs coverage and homogeneity were not compromised and discrepancies obtained with respect to baseline plans were not significant. Furthermore, maximum OARs doses deviations were also not significant. CONCLUSIONS: A 10% reduction in the MU number could be obtained without an alteration of PTV coverage and OARs doses for rectal cancer.

7.
Rep Pract Oncol Radiother ; 24(2): 239-244, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30858768

RESUMEN

Owing to predictable or unpredictable causes, interruptions may arise during therapy. On average, the extension of fractionated radiotherapy treatments is prone to be delayed by several weeks and interruptions can come up extending overall treatment time (OTT). Clonogenic cells of aggressive tumors might benefit from this situation, modifying local control (LC). Preserving treatment quality in radiotherapy is an essential issue for the treatment outcome, and our institution is increasingly concerned about this line of work. Establishing some objective criteria to schedule patients that have suffered interruptions along their treatments is of capital importance and not a trivial issue. Publications strongly encourage departments to minimize the effect of lag periods during treatments. Therefore, in July 2017, our facility implemented the so called 'Protocol to Manage Interruptions in Radiotherapy', based on a scoring system for patient categorization that considers not only histology but also associated comorbidity and sequence of the therapy.

8.
Development ; 141(5): 1059-63, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24550113

RESUMEN

A central issue in biology concerns the presence, timing and nature of phylotypic periods of development, but whether, when and why species exhibit conserved morphologies remains unresolved. Here, we construct a developmental morphospace to show that amniote faces share a period of reduced shape variance and convergent growth trajectories from prominence formation through fusion, after which phenotypic diversity sharply increases. We predict in silico the phenotypic outcomes of unoccupied morphospaces and experimentally validate in vivo that observed convergence is not due to developmental limits on variation but instead from selection against novel trajectories that result in maladaptive facial clefts. These results illustrate how epigenetic factors such as organismal geometry and shape impact facial morphogenesis and alter the locus of adaptive selection to variation in later developmental events.


Asunto(s)
Labio Leporino/embriología , Cresta Neural/citología , Caimanes y Cocodrilos , Animales , Aves , Cricetinae , Humanos , Lagartos , Ratones , Análisis Multivariante , Ratas , Serpientes , Tortugas
9.
J Exp Zool B Mol Dev Evol ; 328(3): 207-229, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28422426

RESUMEN

Since the rise of evo-devo (evolutionary developmental biology) in the 1980s, few authors have attempted to combine the increasing knowledge obtained from the study of model organisms and human medicine with data from comparative anatomy and evolutionary biology in order to investigate the links between development, pathology, and macroevolution. Fortunately, this situation is slowly changing, with a renewed interest in evolutionary developmental pathology (evo-devo-path) in the past decades, as evidenced by the idea to publish this special, and very timely, issue on "Developmental Evolution in Biomedical Research." As all of us have recently been involved, independently, in works related in some way or another with evolution and developmental anomalies, we decided to join our different perspectives and backgrounds in the present contribution for this special issue. Specifically, we provide a brief historical account on the study of the links between evolution, development, and pathologies, followed by a review of the recent work done by each of us, and then by a general discussion on the broader developmental and macroevolutionary implications of our studies and works recently done by other authors. Our primary aims are to highlight the strength of studying developmental anomalies within an evolutionary framework to understand morphological diversity and disease by connecting the recent work done by us and others with the research done and broader ideas proposed by authors such as Étienne Geoffroy Saint-Hilaire, Waddington, Goldschmidt, Gould, and Per Alberch, among many others to pave the way for further and much needed work regarding abnormal development and macroevolution.


Asunto(s)
Anatomía Comparada , Evolución Biológica , Biología Evolutiva , Animales , Dinosaurios/genética , Dinosaurios/crecimiento & desarrollo , Humanos , Lagartos/genética , Lagartos/crecimiento & desarrollo , Teratología
10.
J Theor Biol ; 426: 152-161, 2017 08 07.
Artículo en Inglés | MEDLINE | ID: mdl-28552555

RESUMEN

The present work focuses on the integration of analytical and numerical strategies to investigate the thermal distribution of cancerous breasts. Coupled stationary bioheat transfer equations are considered for the glandular and heterogeneous tumor regions, which are characterized by different thermophysical properties. The cross-section of the cancerous breast is identified by a homogeneous glandular tissue that surrounds the heterogeneous tumor tissue, which is assumed to be a two-phase periodic composite with non-overlapping circular inclusions and a square lattice distribution, wherein the constituents exhibit isotropic thermal conductivity behavior. Asymptotic periodic homogenization method is used to find the effective properties in the heterogeneous region. The tissue effective thermal conductivities are computed analytically and then used in the homogenized model, which is solved numerically. Results are compared with appropriate experimental data reported in the literature. In particular, the tissue scale temperature profile agrees with experimental observations. Moreover, as a novelty result we find that the tumor volume fraction in the heterogeneous zone influences the breast surface temperature.


Asunto(s)
Neoplasias de la Mama/patología , Modelos Biológicos , Temperatura , Femenino , Humanos , Carga Tumoral
11.
Dev Dyn ; 244(9): 1144-1157, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26088476

RESUMEN

BACKGROUND: Amniote gastrulation is often described with respect to human, mouse and chick development by the presence of the primitive streak, a posterior-to-anterior midline morphological cell ingression feature that has come to define Amniote gastrulation. How this midline, ingression-based strategy of gastrulation evolved from the ancestral blastopore, a circumferential involution event in Anamniotes, is unknown. However, within the Amniote clade there exists a more diverse range of gastrulation strategies than just the primitive streak. Investigating gastrulation in a wider range of Amniotes provides a way to understand evolutionary transition from blastopore to the primitive streak. RESULTS: We analysed early to late gastrulation stages of Chamaeleo calyptratus, showing their unique morphology through confocal imaging of F-actin and laminin-stained embryos to visualise cell morphology and assess basal lamina integrity. We analysed the expression pattern of core mesodermal markers Brachyury and Fgf8 and complimented this analysis with that of the turtle, Trachemys scripta. CONCLUSIONS: Our analysis suggests that reptile gastrulation is bi-modal; primary internalization occurs anteriorly by means of an incomplete blastopore-like opening, while posteriorly the cells undergo ingression in the Brachyury-expressing blastoporal plate. This strategy stands mid-way between Anamniotes and Avians/Mammals, suggesting that blastoporal plate is a precursor of the avian primitive streak. Developmental Dynamics 244:1144-1157, 2015. © 2015 Wiley Periodicals, Inc.

12.
BMC Evol Biol ; 15: 184, 2015 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-26382964

RESUMEN

BACKGROUND: One of the most distinctive traits found within Chamaeleonidae is their split/cleft autopodia and the simplified and divergent morphology of the mesopodial skeleton. These anatomical characteristics have facilitated the adaptive radiation of chameleons to arboreal niches. To better understand the homology of chameleon carpal and tarsal elements, the process of syndactyly, cleft formation, and how modification of the mesopodial skeleton has played a role in the evolution and diversification of chameleons, we have studied the Veiled Chameleon (Chamaeleo calyptratus). We analysed limb patterning and morphogenesis through in situ hybridization, in vitro whole embryo culture and pharmacological perturbation, scoring for apoptosis, clefting, and skeletogenesis. Furthermore, we framed our data within a phylogenetic context by performing comparative skeletal analyses in 8 of the 12 currently recognized genera of extant chameleons. RESULTS: Our study uncovered a previously underappreciated degree of mesopodial skeletal diversity in chameleons. Phylogenetically derived chameleons exhibit a 'typical' outgroup complement of mesopodial elements (with the exception of centralia), with twice the number of currently recognized carpal and tarsal elements considered for this clade. In contrast to avians and rodents, mesenchymal clefting in chameleons commences in spite of the maintenance of a robust apical ectodermal ridge (AER). Furthermore, Bmp signaling appears to be important for cleft initiation but not for maintenance of apoptosis. Interdigital cell death therefore may be an ancestral characteristic of the autopodium, however syndactyly is an evolutionary novelty. In addition, we find that the pisiform segments from the ulnare and that chameleons lack an astragalus-calcaneum complex typical of amniotes and have evolved an ankle architecture convergent with amphibians in phylogenetically higher chameleons. CONCLUSION: Our data underscores the importance of comparative and phylogenetic approaches when studying development. Body size may have played a role in the characteristic mesopodial skeletal architecture of chameleons by constraining deployment of the skeletogenic program in the smaller and earliest diverged and basal taxa. Our study challenges the 're-evolution' of osteological features by showing that 're-evolving' a 'lost' feature de novo (contrary to Dollo's Law) may instead be due to so called 'missing structures' being present but underdeveloped and/or fused to other adjacent elements (cryptic features) whose independence may be re-established under changes in adaptive selective pressure.


Asunto(s)
Evolución Biológica , Lagartos/clasificación , Lagartos/genética , Animales , Ecosistema , Extremidades/anatomía & histología , Extremidades/crecimiento & desarrollo , Extremidades/fisiología , Lagartos/crecimiento & desarrollo , Lagartos/fisiología , Morfogénesis , Filogenia
13.
Cir Esp ; 93(4): 236-40, 2015 Apr.
Artículo en Inglés, Español | MEDLINE | ID: mdl-25022843

RESUMEN

INTRODUCTION: Milligan-Morgan and Ferguson haemorrhoidectomy has been the gold standard treatment for symptomatic haemorrhoids for many years. However, escisional techniques are associated with a significant morbidity rate. In recent years, diverse techniques have been described in an attempt to decrease these complications. The guided transanal haemorrhoidal dearterialization THD) doppler is one of these techniques. We report our experience with this new technique. METHODS: We performed a prospective study of 475 patients from 5 hospitals from the National Health System, in Spain. The majority of these patients suffered from third grade haemorrhoids (256 [56%]) and underwent THD. We analyse and compare preoperative and postoperative results as well as the homogeneity of the technique between hospitals. RESULTS: Spinal anaesthesia was the most elected procedure by the anaesthetist (81.0%). Statistically significant differences were found between pre and postoperative symptoms (P=.03), with an overall improvement after surgery. The average hospitalization was 0.4±0.3 days. The mean number of days of oral analgesics was 8.8±2.7 days. The cumulative complication rate is 16%. CONCLUSION: THD is a safe and easily reproducible procedure. Postoperative outcomes demonstrated a low rate of morbidity and recurrence together with early discharge; therefore, a rapid incorporation to daily activities was noted.


Asunto(s)
Hemorreoidectomía/métodos , Hemorroides/cirugía , Canal Anal , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
14.
J Clin Microbiol ; 52(1): 45-51, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24131683

RESUMEN

This study describes the prevalence and genotype distribution of Pneumocystis jirovecii obtained from nasopharyngeal (NP) swabs from immunocompetent Cuban infants and toddlers with whooping cough (WC). A total of 163 NP swabs from 163 young Cuban children with WC who were admitted to the respiratory care units at two pediatric centers were studied. The prevalence of the organism was determined by a quantitative PCR (qPCR) assay targeting the P. jirovecii mitochondrial large subunit (mtLSU) rRNA gene. Genotypes were identified by direct sequencing of mtLSU ribosomal DNA (rDNA) and restriction fragment length polymorphism (RFLP) analysis of the dihydropteroate synthase (DHPS) gene amplicons. qPCR detected P. jirovecii DNA in 48/163 (29.4%) samples. mtLSU rDNA sequence analysis revealed the presence of three different genotypes in the population. Genotype 2 was most common (48%), followed in prevalence by genotypes 1 (23%) and 3 (19%); mixed-genotype infections were seen in 10% of the cases. RFLP analysis of DHPS PCR products revealed four genotypes, 18% of which were associated with resistance to sulfa drugs. Only contact with coughers (prevalence ratio [PR], 3.51 [95% confidence interval {CI}, 1.79 to 6.87]; P = 0.000) and exposure to tobacco smoke (PR, 1.82 [95% CI, 1.14 to 2.92]; P = 0.009) were statistically associated with being colonized by P. jirovecii. The prevalence of P. jirovecii in infants and toddlers with WC and the genotyping results provide evidence that this population represents a potential reservoir and transmission source of P. jirovecii.


Asunto(s)
Infecciones por Pneumocystis/epidemiología , Infecciones por Pneumocystis/microbiología , Pneumocystis carinii/clasificación , Pneumocystis carinii/aislamiento & purificación , Tos Ferina/complicaciones , Niño , Preescolar , Cuba/epidemiología , ADN de Hongos/química , ADN de Hongos/genética , Femenino , Genotipo , Humanos , Lactante , Recién Nacido , Masculino , Datos de Secuencia Molecular , Nasofaringe/microbiología , Pneumocystis carinii/genética , Polimorfismo de Longitud del Fragmento de Restricción , Prevalencia , Reacción en Cadena en Tiempo Real de la Polimerasa , Análisis de Secuencia de ADN , Tos Ferina/microbiología
15.
Cir Esp ; 92(6): 415-20, 2014.
Artículo en Inglés, Español | MEDLINE | ID: mdl-24360251

RESUMEN

BACKGROUND: This study analyses the relationship between the incidence of idiopathic spontaneous pneumothorax (ISP) and atmospheric pressure (AP). METHODS: A total of 288 cases of ISP were included, 229 men and 59 women. The AP of the day of diagnosis, of the 3 prior days and the monthly average was registered. The association between the incidence of ISP and AP was analyzed by calculating standardized incidence ratio (SIR) and Poisson regression. RESULTS: The AP on the day of admission (mean±standard deviation) (1,017.9±7 hectopascals [hPa]) was higher than the monthly average AP (1,016.9±4.1 hPa) (P=.005). There was a monthly distribution pattern of ISP with the highest incidence in the months of January, February and September and the lowest in April. When AP was less than 1,014 hPa, there were fewer cases registered than what would statistically have been expected (58/72 cases). In contrast, when the pressure was higher than 1,019 hPa, the registered cases were more than expected (109/82 cases) (SIR=1.25; 95% CI: 1.04 to 1.51). The risk of ISP increased 1.15 times (95% CI: 1.05 to 1.25, P=.001) for each hPa of AP, regardless of sex, age and monthly average AP. A dose-response relationship was observed, with progressive increases in risk (IRR=1.06 when the AP was 1,014-1016 hPa; 1.17 hPa when the AP was 1,016-1,019 hPa and 1.69 when AP was superior to 1,019 hPa) (P for trend=.089). CONCLUSION: The AP is a risk factor for the onset of idiopathic spontaneous pneumothorax.


Asunto(s)
Presión Atmosférica , Neumotórax/epidemiología , Adulto , Femenino , Humanos , Incidencia , Masculino , Neumotórax/etiología , Estudios Retrospectivos , Estaciones del Año
16.
Nat Ecol Evol ; 8(3): 536-551, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38200368

RESUMEN

The arrangement and morphology of the vertebrate skull reflect functional and ecological demands, making it a highly adaptable structure. However, the fundamental developmental and macroevolutionary mechanisms leading to different vertebrate skull phenotypes remain unclear. Here we exploit the morphological diversity of squamate reptiles to assess the developmental and evolutionary patterns of skull variation and covariation in the whole head. Our geometric morphometric analysis of a complex squamate ontogenetic dataset (209 specimens, 169 embryos, 44 species), covering stages from craniofacial primordia to fully ossified bones, reveals that morphological differences between snake and lizard skulls arose gradually through changes in spatial relationships (heterotopy) followed by alterations in developmental timing or rate (heterochrony). Along with dynamic spatiotemporal changes in the integration pattern of skull bone shape and topology with surrounding brain tissues and sensory organs, we identify a relatively higher phenotypic integration of the developing snake head compared with lizards. The eye, nasal cavity and Jacobson's organ are pivotal in skull morphogenesis, highlighting the importance of sensory rearrangements in snake evolution. Furthermore, our findings demonstrate the importance of early embryonic, ontogenetic and tissue interactions in shaping craniofacial evolution and ecological diversification in squamates, with implications for the nature of cranio-cerebral relations across vertebrates.


Asunto(s)
Cabeza , Cráneo , Animales , Cráneo/anatomía & histología , Osteogénesis
17.
Front Psychol ; 15: 1387162, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38817830

RESUMEN

The connection between physical activity and cognitive function has become a focus of attention in educational research in recent years. Regular exercise has been shown to have significant positive effects on physical health, but it also appears to have a significant impact on cognitive function and academic performance. Of all the exercise modalities, resistance training has drawn interest for its ability to improve cerebral abilities in addition to physical well-being. However, there is limited available knowledge exploring the relationship between resistance training regimens and academic performance. This narrative review aims to investigate the underlying mechanisms linking resistance training to academic performance. Firstly, we will examine the biological mechanisms and psychosocial links that potentially connect resistance training to academic performance to find and describe the different mechanisms by which resistance training improves academic performance. In the next part of the work, we delve into the existing observational and intervention studies that have explored the relationship between resistance training and academic performance. Lastly, we provide practical recommendations for including resistance training in institutional education settings, emphasizing the need of dispelling myths and addressing barriers to increase participation as well as the relevance of considering key training variables and adaptation of protocols to developmental stages, always guided by a properly trained professional. Overall, the available evidence supports that resistance training provides potential benefits to the academic performance of youth students with many biological and psychosocial factors that explain this relationship. However, most of the studies are observational, and broader interventional studies are needed to understand and maximize the benefits of this type of physical exercise.

18.
J Mol Med (Berl) ; 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38935130

RESUMEN

The PD-1/PD-L1 axis is a complex signaling pathway that has an important role in the immune system cells. Programmed cell death protein 1 (PD-1) acts as an immune checkpoint on the T lymphocytes, B lymphocytes, natural killer (NK), macrophages, dendritic cells (DCs), monocytes, and myeloid cells. Its ligand, the programmed cell death 1 ligand (PD-L1), is expressed in the surface of the antigen-presenting cells (APCs). The binding of both promotes the downregulation of the T cell response to ensure the activation to prevent the onset of chronic immune inflammation. This axis in the tumor microenvironment (TME) performs a crucial role in the tumor progression and the escape of the tumor by neutralizing the immune system, the engagement of PD-L1 with PD-1 in the T cell causes dysfunctions, neutralization, and exhaustion, providing the tumor mass production. This review will provide a comprehensive overview of the functions of the PD-1/PD-L1 system in immune function, cancer, and the potential therapeutic implications of the PD-1/PD-L1 pathway for cancer management.

19.
Histol Histopathol ; : 18763, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38832442

RESUMEN

Bone defects are due to trauma, infections, tumors, or aging, including bone fractures, bone metastases, osteoporosis, or osteoarthritis. The global burden of these demands research into innovative strategies that overcome the limitations of conventional autografts. In this sense, the development of three-dimensional (3D) bioprinting has emerged as a promising approach in the field of tissue engineering and regenerative medicine (TERM) for the on-demand generation and transplantation of tissues and organs, including bone. It combines biological materials and living cells, which are precisely positioned layer by layer. Despite obtaining some promising results, 3D bioprinting of bone tissue still faces several challenges, such as generating an effective vascular network to increase tissue viability. In this review, we aim to collect the main knowledge on methods and techniques of 3D bioprinting. Then, we will review the main biomaterials, their composition, and the rationale for their application in 3D bioprinting for the TERM of bone.

20.
Biomolecules ; 14(3)2024 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-38540696

RESUMEN

Calcification is a process of accumulation of calcium in tissues and deposition of calcium salts by the crystallization of PO43- and ionized calcium (Ca2+). It is a crucial process in the development of bones and teeth. However, pathological calcification can occur in almost any soft tissue of the organism. The better studied is vascular calcification, where calcium salts can accumulate in the intima or medial layer or in aortic valves, and it is associated with higher mortality and cardiovascular events, including myocardial infarction, stroke, aortic and peripheral artery disease (PAD), and diabetes or chronic kidney disease (CKD), among others. The process involves an intricate interplay of different cellular components, endothelial cells (ECs), vascular smooth muscle cells (VSMCs), fibroblasts, and pericytes, concurrent with the activation of several signaling pathways, calcium, Wnt, BMP/Smad, and Notch, and the regulation by different molecular mediators, growth factors (GFs), osteogenic factors and matrix vesicles (MVs). In the present review, we aim to explore the cellular players, molecular pathways, biomarkers, and clinical treatment strategies associated with vascular calcification to provide a current and comprehensive overview of the topic.


Asunto(s)
Calcio , Calcificación Vascular , Humanos , Calcio/metabolismo , Células Endoteliales/metabolismo , Sales (Química) , Transducción de Señal , Calcificación Vascular/metabolismo , Células Cultivadas
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