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The temporomandibular joint (TMJ) ligaments play crucial roles in its function or dysfunction. The objective of this study was to describe the macro and microscopic morphology of these ligaments in domestic pigs, aiming to: (1) expand knowledge about the species; (2) provide anatomical references for advancing veterinary therapy and utilizing pigs as animal models in craniofacial research. Heads of young Sus scrofa domesticus were dissected to identify TMJ ligaments. Fragments of these ligaments were collected and processed for subsequent histological analysis with Haematoxylin and eosin staining. The results were qualitatively described. Pigs exhibited a TMJ reinforced by three individualized capsular ligaments: a lateral ligament, attaching to the ventral margin of the zygomatic process of the temporal bone and the lateral margin of the mandibular neck; a caudomedial ligament, attaching to the retroarticular process of the squamous part of the temporal bone and the caudomedial margin of the mandibular neck and a caudolateral ligament, attaching to the ventral margin of the base of the zygomatic process of the temporal bone and the caudal margin of the mandibular neck. The lateral ligament exhibited a greater constitution of dense irregular connective tissue, while the caudomedial and caudolateral ligaments showed a greater constitution of dense regular connective tissue. It is concluded that the TMJ of pigs presents one more ligament than horses, cattle, dogs, cats and what has been described for pigs themselves. We believe these results may contribute to the improvement of veterinary clinical and surgical therapy overall, as well as provide essential morphological information for a better interpretation and application of interspecies results in craniofacial research using pigs as an experimental model, as in the case of humans.
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Ligamentos Articulares , Articulação Temporomandibular , Animais , Articulação Temporomandibular/anatomia & histologia , Ligamentos Articulares/anatomia & histologia , Sus scrofa/anatomia & histologia , Osso Temporal/anatomia & histologia , Suínos/anatomia & histologia , Feminino , Ligamentos/anatomia & histologia , MasculinoRESUMO
The implantation of the embryo into the maternal endometrium is a complex process associated with the evolution of viviparity and placentation in mammals. In this review, we provide an overview of maternal recognition of pregnancy signals and implantation modes in eutherians, focusing on their diverse mechanisms and evolutionary patterns. Different pregnancy recognition signals and implantation modes have evolved in eutherian mammals, reflecting the remarkable diversity of specializations in mammals following the evolution of viviparity. Superficial implantation is the ancestral implantation mode in Eutheria and its major clades. The other modes, secondary, partially, and primary interstitial implantation have each independently evolved multiple times in the evolutionary history of eutherians. Although significant progress has been made in understanding pregnancy recognition signals and implantation modes, there is still much to uncover. Rodents and chiropterans (especially Phyllostomidae) offer valuable opportunities for studying the transitions among implantation modes, but data is still scarce for these diverse orders. Further research should focus on unstudied taxa so we can establish robust patterns of evolutionary changes in pregnancy recognition signaling and implantation modes.
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Cardiovascular diseases are considered the leading cause of mortality globally; even with low mortality in dogs, such diseases are described in the same way in companion animals and humans. This study aimed to devise an effective decellularization protocol for the canine myocardium through the association of physical, chemical, and enzymatic methods, assessing resultant alterations in the myocardial extracellular matrix to obtain a suitable scaffold. Two canine hearts were collected; the samples were sectioned into ±1 cm2 fragments, washed in distilled water and 1× PBS solution, and followed by treatment under four distinct decellularization protocols. Sodium Dodecyl Sulfate (SDS) 1% 7 days + Triton X-100 1% for 48 h (Protocol I); Sodium Dodecyl Sulfate (SDS) 1% 5 days + Triton X-100 1% for 48 h (Protocol II); Trypsin 0.05% for 1 h at 36 °C + freezing -80 °C overnight + Sodium Dodecyl Sulfate (SDS) 1% for 3 days, Triton-X-100 for 48 h hours (Protocol III); 0.05% trypsin for 1 h at 36 °C + freezing at -80 °C overnight + 1% Sodium Dodecyl Sulfate (SDS) for 2 days + 1% Triton-X-100 for 24 h (Protocol IV). After analysis, Protocols I and II showed the removal of cellular content and preservation of extracellular matrix (ECM) contents, unlike Protocols III and IV, which retracted the ECM and removed essential elements of the matrix. In theory, although Protocols I and II have similar results, Protocol II stands out for the preservation of the architecture and components of the extracellular matrix, along with reduced exposure time to reagents, making it the recommended protocol for the development of a canine myocardial scaffold.
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Background: The developmental biology of Kinosternon scorpioides is described, based on the phenotype. This species is important for the flora because they are excellent seed disseminators. In addition, basic embryological information is not yet fully clarified, and this research provides unprecedented information on the chelonian embryology of the Amazonian fauna. Aim: The present study aims to identify the embryology of K. scorpioides in captivity during different periods. Methods: Females were monitored throughout the reproductive cycle, by video monitoring, to identify nests and the presence of newly laid eggs. At regular weekly intervals, embryo samples were collected fixed in a 4% paraformol solution and preserved in 70% alcohol. For the embryonic characterization, we used a stereomicroscope and the scanning electron microscopy method. Results: We describe 15 embryonic stages for a 15-week (105-day) incubation process. Only at 42 days (6th week) was the morphological characterization of a chelonian observed and at the 12th week (Stage XII), the phenotypic characterization of the species K. scorpioides. Conclusion: In view of the evidence, we found that these phases are similar to the other turtles, with structural variations in the appearance and disappearance of structures due to the specific characteristics of the species.
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Desenvolvimento Embrionário , Tartarugas , Animais , Tartarugas/embriologia , Feminino , Embrião não Mamífero , Microscopia Eletrônica de Varredura/veterináriaRESUMO
SUMMARY: The quest for aesthetic procedures is experiencing a steady increase in popularity, concomitant with the expanding array of available treatment options. Of notable interest is the burgeoning trend in the use of minimally invasive techniques. Among the various aspects of facial anatomy, the platysma stands as a pivotal element that significantly influences the aesthetic appearance of the neck region. It has garnered particular attention as a strategic focal point in various treatments geared towards enhancing the neck's visual appeal. Additionally, the versatility of the platysma extends beyond the realm of cosmetic improvements. Its functional significance is recognized in reconstructive surgical procedures, where it may be harnessed for specific maneuvers. Furthermore, the muscle serves as a critical access point for minimally invasive endoscopic surgeries in the neck region. While these developments hold great promise, it is crucial to underscore that safety should always take precedence in any medical or surgical approach. This applies equally to the neck region, which presents a complex and intricate anatomical landscape. An in-depth understanding and meticulous investigation of the platysma in all its diverse aspects are paramount to ensuring the success and safety of any procedure conducted in this region. This comprehensive review aspires to provide a contemporary understanding of the platysma, offering an in-depth analysis that encompasses its intricate anatomy, histological characteristics, and multifaceted clinical implications. By delving into these diverse dimensions, it aims to equip healthcare professionals and researchers with a robust foundation for informed decision-making and practice.
La búsqueda de procedimientos estéticos ha experimentado un aumento constante en popularidad, junto con la creciente gama de opciones de tratamientos disponibles. De notable interés es la creciente tendencia en el uso de técnicas mínimamente invasivas. Entre los diversos aspectos de la anatomía facial, el platisma destaca como un elemento fundamental que influye significativamente en la apariencia estética de la región del cuello. Ha ocasionado especial atención como punto focal estratégico en varios tratamientos orientados a mejorar el atractivo visual del cuello. Además, la versatilidad del platisma se extiende más allá del ámbito de las mejoras cosméticas. Su importancia funcional se reconoce en procedimientos quirúrgicos reconstructivos, donde se puede aprovechar para maniobras específicas. Además, el músculo sirve como punto de acceso crítico para cirugías endoscópicas mínimamente invasivas en la región del cuello. Si bien estos avances son muy prometedores, es fundamental subrayar que la seguridad siempre debe tener prioridad ante cualquier abordaje médico o quirúrgico. Esto se aplica igualmente a la región del cuello, que presenta un aspecto anatómico complejo e intrincado. Una comprensión profunda y una investigación meticulosa del platisma en todos sus diversos aspectos son fundamentales para garantizar el éxito y la seguridad de cualquier procedimiento realizado en esta región. Esta revisión integral aspira a proporcionar una comprensión contemporánea del platisma, ofreciendo un análisis en profundidad que abarca su intrincada anatomía, características histológicas e implicaciones clínicas multifacéticas. Al profundizar en estas diversas dimensiones, su objetivo es dotar a los profesionales e investigadores de la salud de una base sólida para la toma de decisiones y la práctica informadas.
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Humanos , Músculos do Pescoço/anatomia & histologiaRESUMO
SUMMARY: This study evaluated the morphology of alpacas skin. Biopsies were collected and samples were fixed in 10 % neutral buffered formalin for histological procedures. The sections were stained with hematoxylin and eosin, picrosirius red and Masson's trichrome. Types I, III and IV collagen were analyzed by immunohistochemistry. The derma presented sebaceous and sweat glands, as well as follicular groups with medullated fibers. Type I and type IV collagen were observed at epidermis and dermis as well as in glandular structures and hair follicles. The collagen III, was observed only in dermis.
Este estudio evaluó la morfología de la piel de alpacas. Se recogieron biopsias y las muestras se fijaron en formalina tamponada neutra al 10 % para procedimientos histológicos. Las secciones se tiñeron con hematoxilina y eosina, rojo picrosirius y tricrómico de Masson. El colágeno tipo I, III y IV se analizó mediante inmunohistoquímica. La dermis presentó glándulas sebáceas y sudoríparas, así como grupos foliculares con fibras medulares. Se observó colágeno tipo I y tipo IV en la epidermis y la dermis, así como en estructuras glandulares y folículos pilosos. El colágeno III, se observó únicamente en la dermis.
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Animais , Camelídeos Americanos/anatomia & histologia , Tegumento Comum/anatomia & histologia , Imuno-Histoquímica , Microscopia Eletrônica de VarreduraRESUMO
Tamandua mexicana is an anteater species native from Mexico to Peru. This species is of great evolutionary interest because it belongs to one of the oldest clades of placental mammals in the American continent. This study aimed to describe the origin, insertion, and arterial supply of the intrinsic shoulder and brachial muscles of T. mexicana. We also compared the masses of the functional groups. Gross dissections were performed on both thoracic limbs of 13 cadavers. ANOVA followed by Tukey's test was used for statistical analyses. The subscapularis muscle presents a hiatus to the common tendon of the caput breve of the biceps brachii and coracobrachialis muscles. A variant accessory muscle, the m. articularis humeri lateralis, was found on the lateral surface of the shoulder joint. M. deltoideus pars acromialis has two bellies. The teres major muscle is perforated by the aponeurotic origin of the m. tensor fasciae antebrachii. The triceps brachii has two capita longi. The caput mediale is fused with the m. anconeus medialis. The caput laterale can have an accessory belly as an anatomical variant. Among the functional groups, a significant difference was found between the elbow extensors and flexors, with the latter having the lowest mass. In conclusion, the intrinsic muscles of T. mexicana presented unique features for the species, as well as arrangements in mass distribution that evidence a possible evolutionary convergence among species of the Superorder Xenarthra.
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Evolução Biológica , Músculo Esquelético , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/fisiologia , Animais , Ombro/anatomia & histologia , Ombro/fisiologia , Feminino , Masculino , Articulação do Ombro/anatomia & histologia , Articulação do Ombro/fisiologia , Eutérios/anatomia & histologia , Eutérios/fisiologiaRESUMO
Accurately printing customizable scaffolds is a challenging task because of the complexity of bone tissue composition, organization, and mechanical behavior. Graphene oxide (GO) and poly-L-lactic acid (PLLA) have drawn attention in the field of bone regeneration. However, as far as we know, the Fischer-Koch model of the GO/PLLA association for three-dimensional (3D) printing was not previously reported. This study characterizes the properties of GO/PLLA-printed scaffolds in order to achieve reproducibility of the trabecula, from virtual planning to the printed piece, as well as its response to a cell viability assay. Fourier-transform infrared and Raman spectroscopy were performed to evaluate the physicochemical properties of the nanocomposites. Cellular adhesion, proliferation, and growth on the nanocomposites were evaluated using scanning electron microscopy. Cell viability tests revealed no significant differences among different trabeculae and cell types, indicating that these nanocomposites were not cytotoxic. The Fischer Koch modeling yielded satisfactory results and can thus be used in studies directed at diverse medical applications, including bone tissue engineering and implants.
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Hepatic microenvironment plays an essential role in liver regeneration, providing the necessary conditions for cell proliferation, differentiation and tissue rearrangement. One of the key factors for hepatic tissue reconstruction is the extracellular matrix (ECM), which through collagenous and non-collagenous proteins provide a three-dimensional structure that confers support for cell adhesion and assists on their survival and maintenance. In this scenario, placental ECM may be eligible for hepatic tissue reconstruction, once these scaffolds hold the major components required for cell support. Therefore, this preliminary study aimed to access the possibility of mouse embryonic stem cells differentiation into hepatocyte-like cells on placental scaffolds in a three-dimensional dynamic system using a Rotary Cell Culture System. Following a four-phase differentiation protocol that simulates liver embryonic development events, the preliminary results showed that a significant quantity of cells adhered and interacted with the scaffold through outer and inner surfaces. Positive immunolabelling for alpha fetus protein and CK7 suggest presence of hepatoblast phenotype cells, and CK18 and Albumin positive immunolabelling suggest the presence of hepatocyte-like phenotype cells, demonstrating the presence of a heterogeneous population into the recellularized scaffolds. Periodic Acid Schiff-Diastase staining confirmed the presence of glycogen storage, indicating that differentiate cells acquired a hepatic-like phenotype. In conclusion, these preliminary results suggested that mouse placental scaffolds might be used as a biological platform for stem cells differentiation into hepatic-like cells and their establishment, which may be a promissing biomaterial for hepatic tissue reconstruction.
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Placenta , Alicerces Teciduais , Feminino , Gravidez , Animais , Camundongos , Projetos Piloto , Alicerces Teciduais/química , Fígado/metabolismo , Hepatócitos/metabolismo , Diferenciação Celular , Células-Tronco Embrionárias , Matriz Extracelular/metabolismoRESUMO
The application of decellularized scaffolds for artificial tissue reconstruction has been an approach with great therapeutic potential in regenerative medicine. Recently, biomimetic ovarian tissue reconstruction was proposed to reestablish ovarian endocrine functions. Despite many decellularization methods proposed, there is no established protocol for whole ovaries by detergent perfusion that is able to preserve tissue macro and microstructure with higher efficiency. This generated biomaterial may have the potential to be applied for other purposes beyond reproduction and be translated to other areas in the tissue engineering field. Therefore, this study aimed to establish and standardize a protocol for porcine ovaries' decellularization based on detergent perfusion and ultrasonication to obtain functional whole-ovary scaffolds. For that, porcine ovaries (n = 5) were perfused with detergents (0.5% SDS and 1% Triton X-100) and submitted to an ultrasonication bath to produce acellular scaffolds. The decellularization efficiency was evaluated by DAPI staining and total genomic DNA quantification. ECM morphological evaluation was performed by histological, immunohistochemistry, and ultrastructural analyses. ECM physico-chemical composition was evaluated using FTIR and Raman spectroscopy. A cytocompatibility and cell adhesion assay using murine fibroblasts was performed. Results showed that the proposed method was able to remove cellular components efficiently. There was no significant ECM component loss in relation to native tissue, and the scaffolds were cytocompatible and allowed cell attachment. In conclusion, the proposed decellularization protocol produced whole-ovaries scaffolds with preserved ECM composition and great potential for application in tissue engineering.
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Ovário , Alicerces Teciduais , Feminino , Suínos , Camundongos , Animais , Alicerces Teciduais/química , Detergentes/farmacologia , Matriz Extracelular/metabolismo , PerfusãoRESUMO
Calotropis procera (Aiton) Dryand (Apocynaceae), popularly known as milkweed, has been traditionally used to treat diseases particularly associated with gastric disorders, skin disease and inflammatory processes. The present study aimed to review the current scientific evidence regarding the pharmacological effects of C. procera extracted phytochemicals and possible research opportunities as complementary and alternative medicine. Scientific publications were searched in various electronic databases (PubMed, Scopus, Web of Science, Google Scholar, Springer, Wiley, and Mendeley) using the following search terms: Calotropis procera, medicinal plants, toxicity, phytochemical characterization, and biological effects. Collected data showed that cardenolides, steroid glycoside and flavonoids are the main classes of phytochemicals identified in C. procera latex and leaves. In addition, lignans, terpenes, coumarins, and phenolic acids have been reported. These metabolites have been correlated with their biological activities, including mainly antioxidant, anti-inflammatory, antitumoral, hypoglycemic, gastric protective, anti-microbial, insecticide, anti-fungal, anti-parasitic, among others. However, some of the studies were carried out with only a single dose or with a high dose not achievable under physiological conditions. Therefore, the validity of C. procera biological activity may be questionable. Not less important to highlight are the risks associated with its use and the possibility of accumulation of heavy metals that can be toxic. Furthermore, there are no clinical trials with C. procera to date. In conclusion, the need of bioassayguided isolation of bioactive compounds, bioavailability and efficacy, as well as pharmacological and toxicity studies, are needed using in vivo models and clinical trials in order to support the traditionally claimed health benefits.
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Apocynaceae , Calotropis , Calotropis/química , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Extratos Vegetais/química , Látex/química , Látex/farmacologiaRESUMO
Alpaca is a South American camelid, particularly present in Peruvian highlands, where oxygen concentration and atmospheric pressure are very low. Due to this fact, gestational physiology has adapted to preserve the conceptus' and mother's health. In this context, several cellular and molecular features play an essential role during and at the end of gestation. Structural carbohydrates act on maternal-fetal communication, recognize exogenous molecules, and contribute to placental barrier selectivity. Therefore, this study aimed to characterize the structural carbohydrate profiles that are present in the term alpaca placenta, kept in their natural habitat of around 4,000 m height. For this propose, 12 term alpaca placentas were collected, and the material was obtained at the time of birth from camelids raised naturally in the Peruvian highlands, in the Cusco region. All placenta samples were processed for histological analysis. A lectin histochemical investigation was performed using 13 biotinylated lectins, allowing us to determine the location of carbohydrates and their intensity on a semi-quantitative scale. Our results demonstrated that during term gestation, the epitheliochorial alpaca placenta shows a high presence of carbohydrates, particularly glucose, α-linked mannose, N-acetylglucosamine ß (GlcNAc), galactose (αGal), and N-acetylgalactosamine α (GalNAc), present in the trophoblast, amnion epithelium, and mesenchyme, as well as the presence of sialic acid residues and low affinity for fucose. In fetal blood capillaries, the presence of bi- and tri-antennary complex structures and α-linked mannose was predominated. In conclusion, we characterized the glycosylation profile in the term alpaca placenta. Based on our data, compared to those reported in the bibliography, we suggest that these carbohydrates could participate in the labor of these animals that survive in Peruvian extreme environments.
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OBJECTIVES: Diseases associated with the circulatory system are the main causes of worldwide morbidity and mortality, implying the need for vascular implants. Thus, the production of vascular biomaterials has proven to be a promising alternative to therapies used in studies and research related to vascular physiology. The present project aims to achieve the artificial development of blood vessels through the recellularization of vascular scaffolds derived from bovine placental vessels. METHODS: The chorioallantoic surface of the bovine placenta was used to produce decellularized biomaterials. For recellularization, 2.5 x 104 endothelial cells were seeded above each decellularized vessel fragment during three or seven days, when culture were interrupted, and the fragments were fixed for cell attachment analysis. Decellularized and recellularized biomaterials were evaluated by basic histology, scanning electron microscopy, and immunohistochemistry. RESULTS: The decellularization process produced vessels that maintained natural structure and elastin content, and no cells or gDNA remains were observed. Endothelial precursor cells were also attached to lumen and external surface of the decellularized vessel.Conclusion: Our results show a possibility of future uses of this biomaterial in cardiovascular medicine, as in the development of engineered vessels.
FUNDAMENTO: As doenças associadas ao aparelho circulatório são as principais causas de morbidade e mortalidade em todo o mundo, implicando a necessidade de implantes vasculares. Assim, a produção de biomateriais vasculares tem se mostrado uma alternativa promissora às terapias utilizadas em estudos e pesquisas relacionados à fisiologia vascular. OBJETIVOS: O presente projeto visa ao desenvolvimento artificial de vasos sanguíneos pela recelularização de scaffolds vasculares derivados de vasos placentários bovinos. MÉTODOS: A superfície corioalantoide da placenta bovina foi utilizada para produzir biomateriais descelularizados. Para a recelularização, 2,5 x 104 células endoteliais foram semeadas acima de cada fragmento de vaso descelularizado durante três ou sete dias, quando a cultura foi interrompida e os fragmentos foram fixados para análise de adesão celular. Biomateriais descelularizados e recelularizados foram avaliados por histologia básica, microscopia eletrônica de varredura e imuno-histoquímica. RESULTADOS: o processo de descelularização produziu vasos que mantiveram a estrutura natural e o conteúdo de elastina, e não foram observadas células e gDNA remanescentes. Além disso, células precursoras endoteliais se ligaram ao lúmen e à superfície externa do vaso descelularizado. CONCLUSÃO: nossos resultados mostram a possibilidade de usos futuros desse biomaterial na medicina cardiovascular, como, por exemplo, no desenvolvimento de vasos artificiais.
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Fármacos Cardiovasculares , Células Endoteliais , Humanos , Gravidez , Bovinos , Animais , Feminino , Placenta , Materiais BiocompatíveisRESUMO
SUMMARY: Estradiol and progesterone receptors play an essential role in the changes occurring in the uterus during the estrus cycle in dogs (Canis lupus familiaris). In order to investigate the potential effect of progestational agent medroxyprogesterone acetate (MPA) when is used during anestrus on the expression of estradiol receptors [ER], progesterone receptors [PR] and nuclear protein Ki67, we evaluated uterine tissue immunohistochemically. Uteri were grouped as nulliparous (control, n=11), multiparous (n=11) and treated with MPA (n=11; nulliparous with two treatments; 5mg/kg; i.m.). The amount and location of PR, ER and Ki67 were studied on the epithelial surface, apical and basal regions of the endometrium and myometrium using immunohistochemical techniques with a spectral confocal microscope and analyzed by ANOVA. Differences in ER were observed between the multiparous and MPA-treated groups in the apical region of the endometrium (p=0.0022). Differences in cell proliferation were detected between the nulliparous and multiparous groups (p=0.0037) and nulliparous and MPA-treated groups (p=0.0003) in the basal region of the endometrium. In conclusion, two doses of MPA (5mg/kg; i.m.) do not have a significant effect on the expression of ER and PR; however, they inhibit cell proliferation in the basal region of the endometrium, which includes the stroma, subepithelial cell layer, compact layer, and spongy layer. The clinical and long-term effect of this treatment should be evaluated in subsequent studies.
Los receptores de estradiol y progesterona juegan un rol fundamental en los cambios que se producen en el útero durante el ciclo estral de las perras (Canis lupus familiaris). El objetivo de este estudio fue evaluar las expresiones de ER-a y PR en el útero y la proliferación de células endometriales detectando la expresión nuclear de la proteína Ki67 en perras expuestas a la progestina sintética MPA y compararlas con perras nulíparas y multíparas expuestas a progesterona luteal. Úteros fueron agrupados como nulíparas (control, n=11), multíparas (n=11) y tratadas con MPA (n=11; nulíparas con dos tratamientos; 5 mg/kg; i.m.). La expresión de PR, ER-a y Ki67 fue evaluada en la regiones apicales y basales del endometrio y miometrio con un microscopio confocal espectral. Se observó diferencias en ER-a entre los grupos multíparas y tratados con MPA en la región apical del endometrio (p=0,0022). Se detectaron diferencias en la proliferación celular entre los grupos de nulíparas y multíparas (p=0,0037) y los grupos de nulíparas y tratados con MPA (p=0,0003) en la región basal del endometrio. En conclusión, dos dosis de MPA (5mg/kg; i.m.) no tienen un efecto significativo sobre la expresión de ER y PR; sin embargo, inhiben la proliferación celular en la región basal del endometrio, el cual incluye a estroma, capa de células subepiteliales, estratos compacto y esponjoso. El efecto clínico a largo plazo de este tratamiento debe ser evaluado en estudios posteriores.
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Animais , Feminino , Cães , Progesterona/metabolismo , Útero/metabolismo , Receptores de Estrogênio/metabolismo , Antígeno Ki-67/metabolismo , Imuno-Histoquímica , Acetato de Medroxiprogesterona/metabolismoRESUMO
Traditional therapeutic interventions aim to restore male fertile potential or preserve sperm viability in severe cases, such as semen cryopreservation, testicular tissue, germ cell transplantation and testicular graft. However, these techniques demonstrate several methodological, clinical, and biological limitations, that impact in their results. In this scenario, reproductive medicine has sought biotechnological alternatives applied for infertility treatment, or to improve gamete preservation and thus increase reproductive rates in vitro and in vivo. One of the main approaches employed is the biomimetic testicular tissue reconstruction, which uses tissue-engineering principles and methodologies. This strategy pursues to mimic the testicular microenvironment, simulating physiological conditions. Such approach allows male gametes maintenance in culture or produce viable grafts that can be transplanted and restore reproductive functions. In this context, the application of several biomaterials have been proposed to be used in artificial biological systems. From synthetic polymers to decellularized matrixes, each biomaterial has advantages and disadvantages regarding its application in cell culture and tissue reconstruction. Therefore, the present review aims to list the progress that has been made and the continued challenges facing testicular regenerative medicine and the preservation of male reproductive capacity, based on the development of tissue bioengineering approaches for testicular tissue microenvironment reconstruction.
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Materiais Biocompatíveis , Sêmen , Masculino , Humanos , Materiais Biocompatíveis/uso terapêutico , Testículo , Criopreservação/métodos , Engenharia TecidualRESUMO
Reproductive specializations in caviomorphs (infraorder Hystricognathi), are very peculiar within the Order Rodentia. These include long gestations, the birth of offspring with an extreme degree of precociality, and short lactation periods. This study describes the embryo-placental relationship of viable implantation sites (IS) of the plains viscacha, Lagostomus maximus, after 46 post-coital days. The observations recorded in this study are comparatively discussed with those of other hystricognaths and eutherians. At this stage, the embryo resembles that of other eutherians. At this time of embryo development, the placenta exhibits a size, shape, and organization similar to that it will have in its mature state. Besides, the subplacenta is already highly folded. These characteristics are adequate to sustain the development of future precocial offspring. The mesoplacenta, a structure present in other hystricognaths and related to uterine regeneration is described for the first time in this species. This detailed description of the placental and embryonic structure contributes to the knowledge of the reproductive and developmental biology of the viscacha, as well as that of hystricognaths. These characteristics will allow testing other hypotheses related to the morphology and physiology of the placenta and subplacenta, and their relationship with the growth and development of precocial offspring in Hystricognathi.
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Placenta , Roedores , Gravidez , Feminino , Animais , Placenta/anatomia & histologia , Roedores/fisiologia , Reprodução/fisiologia , Desenvolvimento EmbrionárioRESUMO
Diabetes mellitus and pancreatitis are common pancreatic diseases in dogs, affecting the endocrine and exocrine portions of the organ. Dogs have a significant role in the history of research related to genetic diseases, being considered potential models for the study of human diseases. This review discusses the importance of using the extracellular matrix of the canine pancreas as a model for the study of diabetes mellitus and pancreatitis, in addition to focusing on the importance of using extracellular matrix in new regenerative techniques, such as decellularization and recellularization. Unlike humans, rabbits, mice, and pigs, there are no reports in the literature characterizing the healthy pancreatic extracellular matrix in dogs, in addition to the absence of studies related to matrix components that are involved in triggering diabetes melittus and pancreatitis. The extracellular matrix plays the role of physical support for the cells and allows the regulation of various cellular processes. In this context, it has already been demonstrated that physiologic and pathologic pancreatic changes lead to ECM remodeling, highlighting the importance of an in-depth study of the changes associated with pancreatic diseases.
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Procyon cancrivorus and Nasua nasua are two procyonids with different evolutionary adaptations to use their thoracic limbs. Therefore, this study aimed to characterize the differences in the brachial plexus between both species. Five P. cancrivorus and five N. nasua cadavers were used to perform this investigation with the permission of the bioethics committee and environmental license. Gross dissections were performed on the cervical, pectoral, and thoracic limb regions to find the origin and distribution of the brachial plexus. The brachial plexus of both species originated in a variant manner from C5-T1, C5-T2, C6-T1, or C6-T2. All brachial plexus nerves were observed and, interestingly, the musculocutaneous sent a communicating branch to the median nerve medially to the axillary artery, forming an ansa axillaris in both species. An ansa pectoralis was also observed medially to the axillary artery. Additionally, in P. cancrivorus, the musculocutaneous nerve innervates the pronator teres and flexor carpi radialis muscles and communicates with the median nerve at the elbow level to continue as a common trunk at the antebrachium. The brachial plexus has differences between both procyonids, although in both species, it could conserve a primitive arrangement present within the infraorder Arctoidea.
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BACKGROUND: Understanding the elements that support cataract development and searching for available therapeutic methods is essential for scientific and social interest. For that purpose, the role of trace elements has been investigated in this study to better understand the development of cataracts in dogs. OBJECTIVE: The aim of this study was to evaluate the ratio of the major and trace elements by X-ray fluorescence spectrometry in dog cataract lenses to contribute to diagnostic, non-surgical, and ophthalmological preventive data. METHODS: A single lens with a cataract from each of a total of 88 dogs (cataract group) and a healthy lens from each of 6 dogs (control group) were evaluated. The elements calcium (Ca), iron (Fe), copper (Cu), zinc (Zn), magnesium (Mg), manganese (Mn), and potassium (K) were analyzed by energy dispersive X-ray fluorescence and X-ray microfluorescence. RESULTS: The results indicated an increase of Ca, Fe, Cu, and Zn, in association with the reabsorption mechanism of hypermature cataracts. CONCLUSIONS: The ratio of elements Ca, Fe, Cu, and Zn was different in cataract lenses than in healthy lenses, and our results may support the development of therapeutic strategies for cataracts in dogs. The Ca concentrations were distinct in the cataract development stages, and the Fe concentration was relatively higher in males when compared to females. Finally, this research stands out with a particular contribution to the understanding of both cataract formation and prevention.