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1.
An Acad Bras Cienc ; 96(1): e20230441, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38511744

RESUMEN

Studies have highlighted melanoma immunogenicity, and the prognostic importance of tumor infiltrating lymphocytes (TILs) and mechanisms of tumor immune evasion, such as hyperexpression of programmed cell death ligand 1 (PDL-1). High endothelial venules (HEV) are specialized blood vessels that can facilitate the lymphocytes migration to the tumor. Here we evaluate the association of HEV density and PDL-1 expression in primary cutaneous melanomas with the presence and degree of TILs and with other clinicopathological variables (age, sex, tumor location, melanoma histological type, Breslow thickness, ulceration, regression signs, mitotic index). HEV density and PDL-1 expression were assessed immunohistochemically in 78 melanoma cases, using a specific antibody, and were detected in 59% and 76% of these, respectively. Positive associations were identified between HEV density and PDL-1 expression with the presence and degree of lymphocytic infiltration, melanoma histological type and ulceration presence. No correlation was found between HEV density and PDL-1 expression. Our findings confirm the HEV role in the recruitment and facilitation of lymphocyte transport in cutaneous melanomas, where HEV density is strongly associated with the degree of TILs. Additionally, PDL-1 hyperexpression suggests a possible mechanism of tumor immune evasion, which may lead to inactivation and reduction of the tumor lymphocytes number.


Asunto(s)
Melanoma , Neoplasias Cutáneas , Humanos , Melanoma/patología , Linfocitos Infiltrantes de Tumor/metabolismo , Linfocitos Infiltrantes de Tumor/patología , Vénulas/metabolismo , Vénulas/patología , Linfocitos , Pronóstico
2.
J Biomater Appl ; 36(9): 1550-1566, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35130780

RESUMEN

A recent and quite promising technique for bone tissue engineering is the 3D printing, peculiarly regarding the production of high-quality scaffolds. The 3D printed scaffold strictly provides suitable characteristics for living cells, in order to induce treatment, reconstruction and substitution of injured tissue. The purpose of this work was to evaluate the behavior of the 3D scaffold based on Poly(L-co-D,L lactic acid-co-Trimethylene Carbonate) (PLDLA-TMC), which was designed in Solidworks™ software, projected in 3D Slicer™, 3D printed in filament extrusion, cultured with mesenchymal stem cells (MSCs) and tested in vitro and in vivo models. For in vitro study, the MSCs were seeded in a PLDLA-TMC 3D scaffold with 600 µm pore size and submitted to proliferation and osteogenic differentiation. The in vivo assays implanted the PLDLA-TMC scaffolds with or without MSCs in the calvaria of Wistar rats submitted to 8 mm cranial bone defect, in periods of 8-12 weeks. The results showed that PLDLA-TMC 3D scaffolds favored adherence and cell growth, and suggests an osteoinductive activity, which means that the material itself augmented cellular differentiation. The implanted PLDLA-TMC containing MSCs, showed better results after 12 weeks prior grafting, due the absence of inflammatory processes, enlarged regeneration of bone tissue and facilitated angiogenesis. Notwithstanding, the 3D PLDLA-TMC itself implanted enriched tissue repair; the addition of cells known to upregulate tissue healing reinforce the perspectives for the PLDLA-TMC applications in the field of bone tissue engineering in clinical trials.


Asunto(s)
Células Madre Mesenquimatosas , Osteogénesis , Animales , Regeneración Ósea , Diferenciación Celular , Dioxanos , Ácido Láctico , Impresión Tridimensional , Ratas , Ratas Wistar , Ingeniería de Tejidos/métodos , Andamios del Tejido
3.
Artif Organs ; 40(10): 938-949, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26750593

RESUMEN

Several materials are commercially available as substitutes for skin. However, new strategies are needed to improve the treatment of skin wounds. In this study, we developed and characterized a new device consisting of poly(lactic-co-glycolic acid) (PLGA) and collagen associated with mesenchymal stem cells derived from human adipose tissue. To develop the bilaminar device, we initially obtained a membrane of PLGA by dissolving the copolymer in chloroform and then produced a collagen type I scaffold by freeze-drying. The materials were characterized physically by gel permeation chromatography, scanning electron microscopy, and mass loss. Biological activity was assessed by cell proliferation assay. A preliminary study in vivo was performed with a pig model in which tissue regeneration was assessed macroscopically and histologically, the commercial device Integra being used as a control. The PLGA/collagen bilaminar material was porous, hydrolytically degradable, and compatible with skin growth. The polymer complex allowed cell adhesion and proliferation, making it a potentially useful cell carrier. In addition, the transparency of the material allowed monitoring of the lesion when the dressings were changed. Xenogeneic mesenchymal cells cultured on the device (PLGA/collagen/ASC) showed a reduced granulomatous reaction to bovine collagen, down-regulation of α-SMA, enhancement in the number of neoformed blood vessels, and collagen organization as compared with normal skin; the device was superior to other materials tested (PLGA/collagen and Integra) in its ability to stimulate the formation of new cutaneous tissue.


Asunto(s)
Colágeno/química , Ácido Láctico/química , Células Madre Mesenquimatosas/citología , Ácido Poliglicólico/química , Regeneración , Fenómenos Fisiológicos de la Piel , Andamios del Tejido/química , Tejido Adiposo/citología , Animales , Bovinos , Proliferación Celular , Células Cultivadas , Humanos , Trasplante de Células Madre Mesenquimatosas , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Piel/citología , Piel/lesiones , Piel/ultraestructura , Porcinos , Ingeniería de Tejidos/métodos , Cicatrización de Heridas
4.
Pesqui. vet. bras ; Pesqui. vet. bras;35(7): 664-670, jul. 2015. tab, graf
Artículo en Inglés | LILACS | ID: lil-766205

RESUMEN

A 4-year-old female captive-bred snake of the genus Bothrops showed swelling on the left side of the oral cavity, suggesting the development of neoplasia. The mass was removed surgically and sent for pathological examination. Two months later a new increase in volume in the same site was observed, suggesting recurrence. The lesion was completely removed and sent for pathological analysis. Histologically, the two-samples consisted of a mass with highly-cell density composed of spindle-shaped anaplastic cells arranged in interwoven bundles, distributed throughout the tissue extension and, occasionally, polygonal cells arranged in irregular fascicles. The Masson trichrome staining showed modest amount of collagen supporting the neoplastic cells. PAS-positive content was not observed in the cytoplasm of neoplastic cells. Histological and histochemical findings indicated that it was a spindle cell neoplasm, but the classification was not possible. Immunohistochemistry was requested and performed using the streptavidin-biotin-peroxidase method. The markers used were anti-vimentin, anti-PCNA, anti-EMA, anti-melan A and anti-melanosome, anti-desmin, anti-actin, anti-CD68 and anti- S100protein. The neoplastic cells were immunoreactive for vimentin and PCNA and negative for the other antibodies. The morphology characterization, histochemical and immunohistochemical analysis of neoplastic cells allowed the definitive diagnosis of oral fibrosarcoma...


Uma serpente de cativeiro, fêmea, quatro anos de idade, do gênero Bothrops apresentou aumento de volume no lado esquerdo da cavidade oral, sugerindo tratar-se de neoplasma. A massa foi removida cirurgicamente e enviada para exame anatomopatológico. Dois meses depois foi observado novo aumento de volume no mesmo local, sugerindo recidiva. A lesão foi removida por completo e também enviada para análise. Histologicamente, as duas amostras consistiam de massa altamente celular, composta por células anaplásicas fusiformes organizadas em feixes entrelaçados e distribuídos por toda extensão tecidual e, ocasionalmente, células poligonais arranjadas em fascículos irregulares. A coloração de tricrômico de Masson apresentou quantidade modesta de colágeno sustentando as células neoplásicas. Não foi observado conteúdo PAS-positivo no citoplasma das células neoplásicas. Os achados histológicos e histoquímicos indicavam tratar-se de neoplasma de células fusiformes, porém não era possível sua classificação. A imuno-histoquímica foi requisitada e realizada pelo método streptavidina-biotina-peroxidase, utilizando os anticorpos anti-vimentina, anti-PCNA, Anti-EMA, anti-melan A, anti-HMB45, anti-desmina, anti-actina, anti-CD68 e anti-proteína S-100. As células neoplásicas foram imunorreativas para vimentina e PCNA e, negativas para os demais anticorpos. A caracterização morfológica, histoquímica e imuno-histoquímica das células neoplásicas permitiu o diagnóstico definitivo de fibrossarcoma oral...


Asunto(s)
Animales , Bothrops/anatomía & histología , Fibrosarcoma/diagnóstico , Fibrosarcoma/veterinaria , Neoplasias de la Boca/diagnóstico , Neoplasias de la Boca/veterinaria , Serpientes/anatomía & histología , Eosina Amarillenta-(YS) , Antígeno Nuclear de Célula en Proliferación/análisis , Inmunohistoquímica , Inmunohistoquímica/veterinaria , Reacción del Ácido Peryódico de Schiff/veterinaria , Vimentina
5.
Pesqui. vet. bras ; Pesqui. vet. bras;34(8): 776-779, Aug. 2014. ilus
Artículo en Portugués | LILACS | ID: lil-723198

RESUMEN

Graxains-do-campo habitam o centro-leste da América do Sul, desde o sudeste do Brasil e leste da Bolívia. A displasia renal compreende um espectro de anomalias e é frequentemente relatada em cães de diversas raças, sendo a maioria dos relatos achados de necropsia. A maior parte das doenças renais congênitas nos cães apresenta caráter progressivo, portanto o tratamento é limitado e direcionado a fim de retardar a progressão da doença renal estabelecida. No presente relato é descrita a realização de nefrectomia laparoscópica em graxaim-do-campo (Pseudalopex gymnocercus) com displasia renal. Suspeitou-se de doença no rim direito por meio de ultrassonografia e urografia excretora. Para o procedimento cirúrgico foram utilizados três portais (10, 10, 5mm), endoscópio rígido de 10mm/0(0) e clipes para hemostasia dos vasos renais. A técnica cirúrgica utilizada neste canídeo selvagem foi semelhante à usada em cão doméstico, devido à escassez de relatos em cirurgias em graxaim e a inexistência de descrições de nefrectomia videolaparoscópica em graxaim-do-campo. O animal foi acompanhado por um período de 30 dias pós-cirurgia sem a ocorrência de complicações. O presente relato demonstra que a técnica proposta foi adequada para a realização de nefrectomia videolaparoscópica em Graxaim-do-campo...


Pampas fox (Pseudalopex gymnocercus) inhabits east-central South America, from southern Brazil to eastern Bolivia. The renal dysplasia comprises a spectrum of abnormalities and is often reported in dogs of various breeds; but this disease reports involve mostly necropsy findings. Congenital renal diseases in dogs have a progressive character, so that treatment is limited and directed to retard the disease. This report describes a laparoscopic nephrectomy in pampas fox with renal dysplasia. Right kidney disease was suspected by ultrasound and intravenous urography. For the surgical procedure we used three portal accesses (10, 10, 5mm), rigid endoscope 10mm/0(0) and clips for hemostasis of the renal vessels. Due the absence of reports of laparoscopic nephrectomy in pampas fox and scarcity of surgical techniques for this species, the operative technique used was similar to that used in the domestic dog. The pampas fox was monitored for 30 days after surgery without the occurrence of complications. This report demonstrates that the proposed technique is appropriate to perform laparoscopic nephrectomy in pampas fox...


Asunto(s)
Animales , Cirugía Asistida por Video/veterinaria , Zorros , Laparoscopía/veterinaria , Nefrectomía/veterinaria , Insuficiencia Renal Crónica/diagnóstico , Insuficiencia Renal Crónica/veterinaria , Ultrasonografía/veterinaria
6.
Can Vet J ; 52(6): 637-40, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22131580

RESUMEN

This report demonstrates the feasibility of an elective ovariosalpingohysterectomy by natural transluminal endoscopic surgery (NOTES) hybrid technique in a dog. A 5-mm abdominal cannula was used in combination with a 10-mm cannula (vaginal access). The patient's quick recovery and the absence of complications are indicative of the effectiveness of this surgery.


Asunto(s)
Perros/cirugía , Endoscopía/veterinaria , Histerectomía/veterinaria , Ovariectomía/veterinaria , Complicaciones Posoperatorias/veterinaria , Animales , Endoscopía/métodos , Estudios de Factibilidad , Femenino , Histerectomía/métodos , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Procedimientos Quirúrgicos Mínimamente Invasivos/veterinaria , Ovariectomía/métodos , Complicaciones Posoperatorias/epidemiología , Resultado del Tratamiento
7.
Pesqui. vet. bras ; Pesqui. vet. bras;30(7): 566-572, July 2010. ilus, tab
Artículo en Portugués | LILACS | ID: lil-557302

RESUMEN

As doenças respiratórias observadas na clínica médica de pequenos animais são numerosas, assim como as possibilidades diagnósticas, dentre as quais encontram-se os exames laboratoriais, os estudos radiográficos, os lavados broncoalveolares e as biópsias. Na presente pesquisa avaliaram-se os resultados da toracoscopia paraxifoide transdiafragmática para a realização de biópsia pulmonar em cães, sendo utilizados para tanto, 13 animais clinicamente sadios. Sob anestesia geral, produziu-se pneumotórax no volume de 30ml kg-1 de ar ambiente para cada hemitórax. O acesso foi obtido a partir de dois trocartes, posicionados entre o apêndice xifoide e o arco costal, os quais transfixaram o diafragma. O primeiro portal foi empregado para a passagem do endoscópio e o segundo para a utilização de pinça saca-bocado, empregada na obtenção de biópsia. Em seguida, a pinça foi removida e um dreno torácico foi posicionado através do portal. Durante os procedimentos, aferiram-se as frequências respiratória e cardíaca, a saturação de oxigênio, as pressões arterial média e venosa central e os parâmetros hemogasométricos. Os drenos foram removidos num período de até 48 horas de pós-operatório, verificando-se mínima produção de ar e/ou líquido. Concluiu-se se tratar de uma técnica rápida, segura e sem complicações trans e pós-operatórias, permitindo aquisição de material suficiente para a avaliação histológica do pulmão.


There are many respiratory diseases in small animals, as well as the possibilities of diagnoses, as laboratory and radiographic exams, bronchoalveolar lavage and biopsies. This research aimed at assessing the results of transdiaphragmatic paraxiphoid thoracoscopies in pulmonary biopsies of thirteen clinically healthy dogs. Under general anesthesia, each dog was insufflated with 30ml kg-1 of air in each hemithorax; two trocars were placed between the xiphoid appendix and the costal arch through the diaphragm. An endoscope was introduced by the first portal; while the second portal was used to allow access to the nippers in the biopsy forceps. Then, these nippers were removed and replaced by chest tube drainage. During the procedures, respiratory frequency, heart rate, oxygen saturation, arterial pressure and central venous pressure (CVP), hemogasometric parameters were checked. Within 48 hours after the surgery, drains were or drain was removed, with minimal production of air and/or liquid. In conclusion, this is a fast and safe technique, which is free of trans and post surgical complications, thus allowing the collection of sufficient material for pulmonary histological evaluation.


Asunto(s)
Animales , Perros , Biopsia/métodos , Cirugía Torácica Asistida por Video , Técnicas y Procedimientos Diagnósticos , Perros , Pulmón
8.
Rev Bras Parasitol Vet ; 17 Suppl 1: 204-8, 2008 Sep.
Artículo en Portugués | MEDLINE | ID: mdl-20059849

RESUMEN

Ovine toxoplasmosis is a major cause of abortion and placentitis. Lambs with congenital infection are born with encephalitis. Abortions occurred between May and August 2006 in an estate in Três Palmeiras, southern Brazil. This study aimed to assess the frequency of abortion associated with toxoplasmosis among ewes in southern Brazil using indirect hemagglutination and pathoanatomical and immunohistochemical analyses. Blood samples were collected from nine animals for indirect hemagglutination. One fetus underwent necropsy and histopathological and immunohistochemical analyses. Three samples, one of which belonged to the necropsied animals mother, were positive on the serological test. The necropsy revealed pale foci in the liver, lungs with a marbled appearance, heart with severe pallor and brain and cerebellar congestion. Fragments of all organs were collected, fixed in 10% buffered formalin, processed, and stained with hematoxylin-eosin. Microscopically, there were cysts and tachyzoites in the brain in areas of malacia with microgliosis and lymphoplasmacytic infiltration, suggesting toxoplasmic encephalitis. There was also interstitial pneumonia, centrolobular necrosis with structures compatible with tachyzoites, focal lymphocytic myocarditis and acute tubular nephrosis. The immunohistochemical test was positive for Toxoplasma gondii. The results allowed diagnosing the ovine toxoplasmosis.


Asunto(s)
Aborto Veterinario/parasitología , Toxoplasmosis Animal/sangre , Toxoplasmosis Animal/patología , Aborto Veterinario/sangre , Aborto Veterinario/patología , Animales , Femenino , Inmunohistoquímica , Embarazo , Ovinos , Toxoplasmosis Animal/complicaciones
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