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1.
Zookeys ; 1207: 355-368, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39091451

RESUMEN

Pinniped respiratory mites of the species Orthohalarachneattenuata have been recorded from various locations around the world but not from continental Argentina. In the present work, we document for the first time the presence of O.attenuata on Arctocephalusaustralis on the Argentine mainland. A total of 23 adult and 381 immature mites were collected from the nose and nasopharyngeal cavity during a necropsy. The mite ambulacrum is described in adults and larvae. This structure consists of a pretarsus, an extensible pulvillum, a pair of claws and paradactyli (pretarsus opercula). The ambulacral structures also have some peculiarities, such as the presence of longitudinal furrows in the claws, straight claws in legs II and III (as opposed to curved in legs I and IV), and the fin-shaped paradactyli. The morphology of the ambulacrum of this mite is interpreted as an adaptation for anchoring to different surfaces of the host, and the protective structures present in the larvae as an adaptation for the dispersal phase in the external environment.

2.
Chem Phys Lipids ; 264: 105423, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39097132

RESUMEN

Staphylococcus aureus infections and its biofilm removal is an important concern in health care management. Methicillin-resistant S. aureus is responsible for severe morbidity and mortality worldwide. The extensive use of disinfectants against biofilms has led to negative environmental impacts. Developing new and more potent biofilm eradication agents with minimal detrimental effects on human and environmental health is currently on the agenda. The alkyl esters of L-ascorbic acid (ASCn) are antioxidant amphiphiles, which show antimicrobial capacity against methicillin-sensitive and resistant S. aureus strains. ASC12 and ASC14 formulations are able to kill the persister cells of the deepest layers of the biofilm. We tested the hypothesis that the antimicrobial and antibiofilm capacity found for the ASCn emerges from a combined effect of its amphiphilic and their redox capacity. This mechanism appears related to: I) a larger diffusion capacity of the ASC12 micelles than ASC14 and ASC16 microstructures; II) the neutralization of the ASCn acid hydroxyl when the amphiphile reaches the surface of an anionic surface, followed by a rapid insertion; III) the disruption of cell membrane by alteration of membrane tension and structure and IV) ASCn accumulation in the cell membrane or biofilm extracellular matrix surfaces, reducing functional chemical groups and affecting its biological function.


Asunto(s)
Antibacterianos , Ácido Ascórbico , Biopelículas , Staphylococcus aureus Resistente a Meticilina , Pruebas de Sensibilidad Microbiana , Biopelículas/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Ácido Ascórbico/química , Ácido Ascórbico/farmacología , Antibacterianos/farmacología , Antibacterianos/química , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Membrana Celular/química , Tensoactivos/química , Tensoactivos/farmacología
3.
Vet Sci ; 11(7)2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-39057988

RESUMEN

Variations in the size of animals of the same species but of different sex are called sexual size dimorphism. The aim of this study was to compare the biometrics between males and females of the Sanmartinero creole bovine, of Colombia, to establish if sexual dimorphism appears in the breed. A total of 94 animals (16 uncastrated males and 78 females, average age of 4.3 ± 1.4 and 4.2 ± 2.3 years, respectively) from three different farms were measured. A total of 21 linear variables were obtained using standard morphometric methods and live weight. A one-way NPMANOVA was used to evaluate between sexes, ages, and farms, a Principal Component Analysis was used to detect the most discriminating variables, and a multivariate regression used age as an independent value. Statistically significant differences were reflected between sexes (p = 0.033) and not by age and farms. The variables that differentiated the most between males and females were those related to size (thoracic circumference, body length, dorso-sternal diameter, height at the withers, height at the rump, and horn length), variables that were biased toward males, although only the height at the withers and the rump were the ones that presented statistically significant differences.

4.
Curr Issues Mol Biol ; 46(6): 5744-5776, 2024 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-38921015

RESUMEN

In the SARS-CoV-2 lineage, RNA elements essential for its viral life cycle, including genome replication and gene expression, have been identified. Still, the precise structures and functions of these RNA regions in coronaviruses remain poorly understood. This lack of knowledge points out the need for further research to better understand these crucial aspects of viral biology and, in time, prepare for future outbreaks. In this research, the in silico analysis of the cis RNA structures that act in the alpha-, beta-, gamma-, and deltacoronavirus genera has provided a detailed view of the presence and adaptation of the structures of these elements in coronaviruses. The results emphasize the importance of these cis elements in viral biology and their variability between different viral variants. Some coronavirus variants in some groups, depending on the cis element (stem-loop1 and -2; pseudoknot stem-loop1 and -2, and s2m), exhibited functional adaptation. Additionally, the conformation flexibility of the s2m element in the SARS variants was determined, suggesting a coevolution of this element in this viral group. The variability in secondary structures suggests genomic adaptations that may be related to replication processes, genetic regulation, as well as the specific pathogenicity of each variant. The results suggest that RNA structures in coronaviruses can adapt and evolve toward different viral variants, which has important implications for viral adaptation, pathogenicity, and future therapeutic strategies.

5.
Heliyon ; 10(9): e30111, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38720764

RESUMEN

The current study provides critical insights into the field of geomorphology by examining the impact of lithological structures and tectonic activities on the geomorphological configuration of terrain and drainage networks in the southeast of Paraíba and northeast of Pernambuco, Brazil. This geographical region is characterized by phenomena of uplift and fluvial incision at various sites, yet remains inadequately explored with respect to its active deformation and the broader context of its recent geology. Therefore, the primary aim of this research is to elucidate the morphostructural and neotectonic influences on the geomorphological formations in these sectors of Brazil. The methodology encompasses morphostructural analysis, leveraging data derived from altimetry, slope, and geomorphology maps, categorized into taxonomic terrain units. Additionally, this research incorporates the use of morphometric indices, including the Stream Length-Gradient Index (SL), Valley Floor Width (VF), and Asymmetry Factor (AF) to quantify geomorphological anomalies. The analysis of the SL index indicates that a significant portion (87.5 %) of the drainage network exhibits anomalies. Furthermore, the VF index results reveal that 66 % of the profiles analyzed manifest anomalies of various magnitudes. Within the study region, the AF index elucidates the distribution of sub-basins into categories of low (0-30), medium (31-50), and high (>51) asymmetry, comprising 25 %, 31 %, and 44 % of the sub-basins, respectively. The sub-basins demonstrate channel disequilibrium, as evidenced by the SL index, attributed to numerous transient knickpoints along the drainage profiles. This observation is consistent with previous findings in the Koyna-Warna Shallow Seismic Region. The study's outcomes reveal both qualitatively and quantitatively anomalous patterns in the drainage network and terrain forms, which are likely indicative of recent tectonic events affecting the entire eastern edge of Northeast Brazil. Consequently, the findings highlight the significant role of post-Miocene tectonic events in shaping the relief of the study area.

6.
Cir Cir ; 92(2): 242-247, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38782378

RESUMEN

OBJECTIVE: To describe a novel dissector device useful in laparoscopy, better definition of anatomic structures to have a better dissection, separation, and cleaning of the structures. METHOD: The endoscopic dissector DisePad was designed and developed at the experimental surgery department of Centro Médico Nacional 20 de Noviembre, and properly patented at Instituto Mexicano de la Propiedad Industrial (title 3512). RESULTS: The tip of the device is the most important component, by its direct contact with the different tissues, consists of a cotton-polyester black cloth impregnated with a special gel immersed into a hot saline solution. Once soaked the tip maintains the solution temperature on itself. CONCLUSIONS: This device has been used in 364 laparoscopic procedures demonstrating, its utility to visualize, separate and clean anatomical structures without thermal lesion, tear, hemorrhage or visceral perforation.


OBJETIVO: Describir un nuevo dispositivo disector en laparoscopia, con una mejor definición de las estructuras anatómicas para obtener una mejor disección,separación y limpieza de las estructuras. MÉTODO: El disector endoscópico DisePad fue diseñado y desarrollado en el servicio de cirugía experimental del Centro Médico Nacional 20 de Noviembre, y patentado ante el Instituto Mexicano de la Propiedad Industrial (registro n.º 3512). RESULTADOS: El componente más importante del disector es la punta que tiene contacto con los tejidos: es una tela de algodón-poliéster negra impregnada en un gel (patentado) que, al ser sumergido en un termo con solución salina caliente, permite retener la temperatura. CONCLUSIONES: Este dispositivo ha sido utilizado en 364 procedimientos quirúrgicos por vía laparoscópica y ha demostrado ser útil para visualizar, separar y limpiar estructuras anatómicas sin producir daño por lesión térmica, desgarre, hemorragia ni perforación visceral.


Asunto(s)
Diseño de Equipo , Laparoscopía , Laparoscopía/instrumentación , Humanos , Disección/instrumentación
7.
J Morphol ; 285(4): e21693, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38602442

RESUMEN

In insect taxa with homogeneous external morphology, genital structures often emerge as essential traits for interspecific differentiation. In the tribe Ptomaphagini (Coleoptera, Leiodidae, Cholevinae), precise identification often depends on analyzing the male genital morphology, even at the genus level. Here, we present a new character for diagnosing the genera Paulipalpina Gnaspini & Peck, 1996 and Parapaulipalpina Gnaspini, 1996. This feature, which we dub 'paralobe', is a projection arising from the internal surface of the right lobe of the aedeagal apex. Based on its absence in other beetles, including other Ptomaphagini, we recognize it as a putative synapomorphy for those genera. The recognition of this previously overlooked structure adds important information for understanding the sequence of changes that occurred in the male genitalia among the genera of Ptomaphagini.


Asunto(s)
Escarabajos , Masculino , Animales , Fenotipo
8.
J Phys Condens Matter ; 36(32)2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38478995

RESUMEN

We present a theoretical investigation of the Goös-Hanchen shift (GHS) experienced by acoustic and optical vibrational modes reflected and transmitted from the surfaces of a semiconductor thin film sandwiched between two semi-infinite media. Our study focuses on the impact of the incident angle on the GHS, considering the coupling between longitudinal and transverse modes. For acoustic vibrations, our findings reveal that the GHS can reach magnitudes up to seven times larger than the thickness of the thin film and up to 20 times larger than the incident wavelength. Besides, it is shown that this significant amplification of the GHS highlights the strong influence of the incident angle and the frequency of the modes involved. In the case of optical vibrations, we observe even more pronounced GHS values, exceeding 30 times the incident wavelength. This demonstrates the potential of GHS in acoustical systems, which opens up possibilities for applications in the design of acoustic devices.

9.
Ecol Evol ; 14(2): e10931, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38348017

RESUMEN

Laguna Verde's dome-shaped structures are distinctive formations within the Central Andes, displaying unique geomicrobiological features. This study represents a pioneering investigation into these structures, assessing their formation, associated taxa, and ecological significance. Through a multifaceted approach that includes chemical analysis of the water body, multiscale characterization of the domes, and analysis of the associated microorganisms, we reveal the complex interplay between geology and biology in this extreme environment. The lake's alkaline waters that are rich in dissolved cations and anions such as chloride, sodium sulfate, and potassium, coupled with its location at the margin of the Antofalla salt flat, fed by alluvial fans and hydrothermal input, provide favorable conditions for mineral precipitation and support for the microorganism's activity. Laguna Verde's dome-shaped structures are mainly composed of gypsum and halite, displaying an internal heterogeneous mesostructure consisting of three zones: microcrystalline, organic (orange and green layers), and crystalline. The green layer of the organic zone is predominantly composed of Proteobacteria, Bacteroidetes, and Cyanobacteria, while the orange layer is mostly inhabited by Cyanobacteria. The results of the study suggest that oxygenic photosynthesis performed by Cyanobacteria is the main carbon fixation pathway in the microbial community, supported by carbon isotopic ratios of specific biomarkers. This finding highlights the important role played by Cyanobacteria in this ecosystem.

10.
Mar Genomics ; 73: 101085, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38301367

RESUMEN

We present a de novo transcriptome assembly for the non-model Antarctic polychaete worm Microspio moorei (Spionidae) collected during Antarctic field expedition in Fildes Bay, King George Island, Antarctic Peninsula, in 2017. Here, we report the first transcriptome reference array for Microspio spp. The gene sequences of the spionid worm were annotated from a wide range of functions (i.e., biological, and metabolic processes, catalytic processes, and catalytic activity). HSP70, HSP90 SOD and CAT families were compared to reported annelid transcriptomes and proteomes. The phylogenetic analysis using COI, 16S, and 18S markers effectively clusters the species within the family. However, it also casts uncertainty on the monophyletic nature of the Microspio genera, indicating the necessity for additional data and potentially requiring a reevaluation of its grouping. Within these protein families, 3D model software was used to create one representative of their protein structures. Structural predictions were compared with related reported annelids living at different temperatures and a human X-ray reference. We found structural differences (RMSE >1.8) between the human HSP proteins but no significant differences between the polychaete-predicted proteins (RMSE <1.2). These results encourage further research of heat stress-related proteins, the development of genetic markers for climate change-induced temperature stress, and the study of the underlying mechanisms of the heat response. Moreover, these results motivate the extension of these findings to congeneric species.


Asunto(s)
Proteínas de Choque Térmico , Transcriptoma , Humanos , Proteínas de Choque Térmico/genética , Filogenia , Regiones Antárticas , Respuesta al Choque Térmico , Superóxido Dismutasa/genética
11.
Biol Rev Camb Philos Soc ; 99(3): 950-964, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38305571

RESUMEN

Cilia are widely present in metazoans and have various sensory and motor functions, including collection of particles through feeding currents in suspensivorous animals. Suspended particles occur at low densities and are too small to be captured individually, and therefore must be concentrated. Animals that feed on these particles have developed different mechanisms to encounter and capture their food. These mechanisms occur in three phases: (i) encounter; (ii) capture; and (iii) particle handling, which occurs by means of a cilia-generated current or the movement of capturing structures (e.g. tentacles) that transport the particle to the mouth. Cilia may be involved in any of these phases. Some cnidarians, as do other suspensivorous animals, utilise cilia in their feeding mechanisms. However, few studies have considered ciliary flow when examining the biomechanics of cnidarian feeding. Anthozoans (sessile cnidarians) are known to possess flow-promoting cilia, but these are absent in medusae. The traditional view is that jellyfish capture prey only by means of nematocysts (stinging structures) and mucus, and do not possess cilia that collect suspended particles. Herein, we first provide an overview of suspension feeding in invertebrates, and then critically analyse the presence, distribution, and function of cilia in the Cnidaria (mainly Medusozoa), with a focus on particle collection (suspension feeding). We analyse the different mechanisms of suspension feeding and sort them according to our proposed classification framework. We present a scheme for the phases of pelagic jellyfish suspension feeding based on this classification. There is evidence that cilia create currents but act only in phases 1 and 3 of suspension feeding in medusozoans. Research suggests that some scyphomedusae must exploit other nutritional sources besides prey captured by nematocysts and mucus, since the resources provided by this diet alone are insufficient to meet their energy requirements. Therefore, smaller particles and prey may be captured through other phase-2 mechanisms that could involve ciliary currents. We hypothesise that medusae, besides capturing prey by nematocysts (present in the tentacles and oral arms), also capture small particles with their cilia, therefore expanding their trophic niche and suggesting reinterpretation of the trophic role of medusoid cnidarians as exclusively plankton predators. We suggest further study of particle collection by ciliary action and its influence on the biomechanics of jellyfishes, to expand our understanding of the ecology of this group.


Asunto(s)
Cilios , Conducta Alimentaria , Animales , Cilios/fisiología , Conducta Alimentaria/fisiología , Cnidarios/fisiología
12.
Molecules ; 29(1)2024 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-38202857

RESUMEN

This work highlights the significant potential of marine toxins, particularly saxitoxin (STX) and its derivatives, in the exploration of novel pharmaceuticals. These toxins, produced by aquatic microorganisms and collected by bivalve mollusks and other filter-feeding organisms, offer a vast reservoir of chemical and biological diversity. They interact with sodium channels in physiological processes, affecting various functions in organisms. Exposure to these toxins can lead to symptoms ranging from tingling sensations to respiratory failure and cardiovascular shock, with STX being one of the most potent. The structural diversity of STX derivatives, categorized into carbamate, N-sulfocarbamoyl, decarbamoyl, and deoxydecarbamoyl toxins, offers potential for drug development. The research described in this work aimed to computationally characterize 18 STX derivatives, exploring their reactivity properties within marine sponges using conceptual density functional theory (CDFT) techniques. Additionally, their pharmacokinetic properties, bioavailability, and drug-likeness scores were assessed. The outcomes of this research were the chemical reactivity parameters calculated via CDFT as well as the estimated pharmacokinetic and ADME properties derived using computational tools. While they may not align directly, the integration of these distinct datasets enriches our comprehensive understanding of the compound's properties and potential applications. Thus, this study holds promise for uncovering new pharmaceutical candidates from the considered marine toxins.


Asunto(s)
Toxinas Marinas , Saxitoxina , Biodiversidad , Disponibilidad Biológica , Preparaciones Farmacéuticas
13.
Cancers (Basel) ; 16(2)2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38254885

RESUMEN

This narrative review aims to clarify the role of tertiary lymphoid structures in breast cancer. We examine their development, composition, and prognostic value, and current ways of recognizing them. A comprehensive literature review was performed using the PubMed/Medline, Scopus, and EMBASE databases. A significant area of interest in breast cancer research involves targeting immune checkpoint molecules, particularly in the triple-negative subtype, where treatment options remain limited. However, existing biomarkers have limitations in accurately predicting treatment response. In this context, tertiary lymphoid structures (TLSs) emerge as a prognostic biomarker and also as a promising predictive marker for response. TLSs are ectopic lymphoid formations or neo-organogenesis that can develop after prolonged exposure to inflammatory signals mediated by chemokines and cytokines. Their presence is inversely correlated with estrogen receptor (ER) and/or progesterone receptor (PR) expression, but positively associated with a higher pathologic complete response rate and improved overall survival. In certain scenarios, TLS-positive tumors were associated with improved outcomes regardless of the presence of PDL-1 (programmed cell death ligand 1) expression or TILs (tumor-infiltrating lymphocytes).

14.
Braz. j. biol ; 842024.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469290

RESUMEN

Abstract In recent years, the development of high-throughput technologies for obtaining sequence data leveraged the possibility of analysis of protein data in silico. However, when it comes to viral polyprotein interaction studies, there is a gap in the representation of those proteins, given their size and length. The prepare for studies using state-of-the-art techniques such as Machine Learning, a good representation of such proteins is a must. We present an alternative to this problem, implementing a fragmentation and modeling protocol to prepare those polyproteins in the form of peptide fragments. Such procedure is made by several scripts, implemented together on the workflow we call PolyPRep, a tool written in Python script and available in GitHub. This software is freely available only for noncommercial users.


Resumo Nos últimos anos, o desenvolvimento de tecnologias de alto rendimento para obtenção de dados sequenciais potencializou a possibilidade de análise de dados proteicos in silico. No entanto, quando se trata de estudos de interação de poliproteínas virais, existe uma lacuna na representação dessas proteínas, devido ao seu tamanho e comprimento. Para estudos utilizando técnicas de ponta como o Aprendizado de Máquina, uma boa representação dessas proteínas é imprescindível. Apresentamos uma alternativa para este problema, implementando um protocolo de fragmentação e modelagem para preparar essas poliproteínas na forma de fragmentos de peptídeos. Tal procedimento é feito por diversos scripts, implementados em conjunto no workflow que chamamos de PolyPRep, uma ferramenta escrita em script Python e disponível no GitHub. Este software está disponível gratuitamente apenas para usuários não comerciais.

15.
Braz. j. biol ; 84: e245592, 2024. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1355866

RESUMEN

Abstract In recent years, the development of high-throughput technologies for obtaining sequence data leveraged the possibility of analysis of protein data in silico. However, when it comes to viral polyprotein interaction studies, there is a gap in the representation of those proteins, given their size and length. The prepare for studies using state-of-the-art techniques such as Machine Learning, a good representation of such proteins is a must. We present an alternative to this problem, implementing a fragmentation and modeling protocol to prepare those polyproteins in the form of peptide fragments. Such procedure is made by several scripts, implemented together on the workflow we call PolyPRep, a tool written in Python script and available in GitHub. This software is freely available only for noncommercial users.


Resumo Nos últimos anos, o desenvolvimento de tecnologias de alto rendimento para obtenção de dados sequenciais potencializou a possibilidade de análise de dados proteicos in silico. No entanto, quando se trata de estudos de interação de poliproteínas virais, existe uma lacuna na representação dessas proteínas, devido ao seu tamanho e comprimento. Para estudos utilizando técnicas de ponta como o Aprendizado de Máquina, uma boa representação dessas proteínas é imprescindível. Apresentamos uma alternativa para este problema, implementando um protocolo de fragmentação e modelagem para preparar essas poliproteínas na forma de fragmentos de peptídeos. Tal procedimento é feito por diversos scripts, implementados em conjunto no workflow que chamamos de PolyPRep, uma ferramenta escrita em script Python e disponível no GitHub. Este software está disponível gratuitamente apenas para usuários não comerciais.


Asunto(s)
Proteasa del VIH , Poliproteínas , Programas Informáticos , Simulación del Acoplamiento Molecular
16.
Chem Biodivers ; 21(2): e202301616, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38161186

RESUMEN

Secretory structures in plants play a crucial role in producing bioactive compounds. Despite the potential of the Swartzia genus, comprehensive studies in this context are still scarce. Swartzia is a legume tree (Fabaceae) that occurs in the Brazilian Atlantic Forest, a biodiversity hotspot, and includes species such as Swartzia flaemingii. Therefore, we aim to achieve: (1) identify and characterize the key secretory sites responsible for saponin production in S. flaemingii leaflets; (2) confirm the presence of saponins in S. flaemingii leaves by comparing them with known chemical profiles of other Swartzia species; (3) assess the potential hemolytic and cytotoxic effects of crude leaf extracts. Our investigation unveils the presence of phenolic idioblasts, mucilage cells, and articulate laticifers, which play pivotal roles in defense and adaptation. Notably, we report the first-ever ultrastructural details of laticifers in a legume species. Additionally, oleanane-type saponins were identified in the leaves, giving insights into the chemotaxonomic profile of Swartzia. The crude extracts show low cytotoxicity levels, showcasing as a promising alternative source of saponins. This investigation reinforces the importance of conserving plants in threatened regions like the Atlantic Forest, a global biodiversity hotspot facing substantial anthropogenic pressures.


Asunto(s)
Fabaceae , Saponinas , Fabaceae/química , Árboles , Saponinas/farmacología , Saponinas/química , Brasil
17.
Microbiol Spectr ; 11(6): e0161323, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-37962394

RESUMEN

IMPORTANCE: We identify both canonical and novel human leukocyte antigen (HLA)-HIV associations, providing a first step toward improved understanding of HIV immune control among the understudied Honduras Mestizo population. Our results are relevant to understanding the protective or detrimental effects of HLA subtypes in Latin America because their unique HLA diversity poses challenges for designing vaccines against HIV and interpreting results from such vaccine trials. Likewise, the description of the HLA profile in an understudied population that shows a unique HLA immunogenetic background is not only relevant for HIV immunology but also relevant in population genetics, molecular anthropology, susceptibility to other infections, autoimmune diseases, and allograft transplantation.


Asunto(s)
Infecciones por VIH , VIH-1 , Humanos , Frecuencia de los Genes , Honduras , VIH-1/genética , Genética de Población , Antígenos HLA/genética , Alelos , Receptores CCR5/genética
18.
Cells ; 12(19)2023 10 08.
Artículo en Inglés | MEDLINE | ID: mdl-37830632

RESUMEN

Cell-in-cell (CIC) structures contribute to tumor aggressiveness and poor prognosis in oral squamous cell carcinoma (OSCC). In vitro 3D models may contribute to the understanding of the underlying molecular mechanisms of these events. We employed a spheroid model to study the CIC structures in OSCC. Spheroids were obtained from OSCC (HSC3) and cancer-associated fibroblast (CAF) lines using the Nanoshuttle-PLTM bioprinting system (Greiner Bio-One). Spheroid form, size, and reproducibility were evaluated over time (EvosTM XL; ImageJ version 1.8). Slides were assembled, stained (hematoxylin and eosin), and scanned (Axio Imager Z2/VSLIDE) using the OlyVIA System (Olympus Life Science) and ImageJ software (NIH) for cellular morphology and tumor zone formation (hypoxia and/or proliferative zones) analysis. CIC occurrence, complexity, and morphology were assessed considering the spheroid regions. Well-formed spheroids were observed within 6 h of incubation, showing the morphological aspects of the tumor microenvironment, such as hypoxic (core) and proliferative zone (periphery) formation. CIC structures were found in both homotypic and heterotypic groups, predominantly in the proliferative zone of the mixed HSC3/CAF spheroids. "Complex cannibalism" events were also noted. These results showcase the potential of this model in further studies on CIC morphology, formation, and relationship with tumor prognosis.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Neoplasias de la Boca , Humanos , Carcinoma de Células Escamosas de Cabeza y Cuello , Carcinoma de Células Escamosas/patología , Neoplasias de la Boca/patología , Reproducibilidad de los Resultados , Microambiente Tumoral
19.
Sensors (Basel) ; 23(17)2023 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-37687788

RESUMEN

This paper presents the development and application of an optical fiber-embedded tendon based on biomimetic multifunctional structures. The tendon was fabricated using a thermocure resin (polyurethane) and the three optical fibers with one fiber Bragg grating (FBG) inscribed in each fiber. The first step in the FBG-integrated artificial tendon analysis is the mechanical properties assessment through stress-strain curves, which indicated the customization of the proposed device, since it is possible to tailor the Young's modulus and strain limit of the tendon as a function of the integrated optical fibers, where the coated and uncoated fibers lead to differences in both parameters, i.e., strain limits and Young's modulus. Then, the artificial tendon integrated with FBG sensors undergoes three types of characterization, which assesses the influence of temperature, single-axis strain, and curvature. Results show similarities in the temperature responses in all analyzed FBGs, where the variations are related to the heterogeneity on the polyurethane matrix distribution. In contrast, the FBGs embedded in the tendon presented a reduction in the strain sensitivity when compared with the bare FBGs (i.e., without the integration in the artificial tendon). Such results demonstrated a reduction in the sensitivity as high as 77% when compared with the bare FBGs, which is related to strain field distributions in the FBGs when embedded in the tendon. In addition, the curvature tests indicated variations in both optical power and wavelength shift, where both parameters are used on the angle estimation using the proposed multifunctional artificial tendon. To that extent, root mean squared error of around 3.25° is obtained when both spectral features are considered. Therefore, the proposed approach indicates a suitable method for the development of smart structures in which the multifunctional capability of the device leads to the possibility of using not only as a structural element in tendon-driven actuators and devices, but also as a sensor element for the different structures.

20.
Vox Sang ; 118(10): 881-890, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37559188

RESUMEN

BACKGROUND AND OBJECTIVES: Computational biology analyses the theoretical tertiary structure of proteins and identifies the 'topological' differences between RhD and RhCE. Our aim was to identify the theoretical structural differences between the four isoforms of RhCE and RhD using computational biological tools. MATERIALS AND METHODS: Physicochemical profile was determined by hydrophobicity and electrostatic potential analysis. Secondary and tertiary structures were generated using computational biology tools. The structures were evaluated and validated using Ramachandran algorithm, which calculates the single score, p-value and root mean square deviation (RMSD). Structures were overlaid on local refinement of 'RhAG-RhCE-ANK' (PBDID 7uzq) and RhAG to compare their spatial distribution within the membrane. RESULTS: All proteins differed in surface area and electrostatic distance due to variations in hydrophobicity and electrostatic potential. The RMSD between RhD and RhCE was 0.46 ± 0.04 Å, and the comparison within RhCE was 0.57 ± 0.08 Å. The percentage of amino acids in the hydrophobic thickness was 50.24% for RhD while for RhCE it ranged between 73.08% and 76.68%. The RHAG hydrophobic thickness was 34.2 Å, and RhCE's hydrophobic thickness was 33.83 Å. We suggest that the C/c antigens differ exofacially at loops L1 and L2. For the E/e antigens, the difference lies in L6. By contrast, L4 is the same for all proteins except Rhce. CONCLUSION: The physicochemical properties of Rh proteins made them different, although their genes are homologous. Using computational biology, we model structures with sufficient precision, similar to those obtained experimentally. An amino acid variation alters the folding of the tertiary structure and the interactions with other proteins, modifying the electrostatic environment, the spatial conformations and therefore the antigenic recognition.

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