RESUMO
The roe deer bucks represent a spontaneous model to study the synchronized testicular involution and recrudescence cycles. However, cellular processes and hormonal control of steroidogenic glands are scarcely known. For the present study testes and adrenal glands obtained from roe deer during the pre-rut season were used. We aimed to determine (i) senescence and autophagy involvement in testis atrophy (immunohistochemical analysis for tumor suppressor protein encoded by the cyclin-dependent kinase inhibitor 2A; p16 and microtubule-associated protein 1A/1B-light chain 3; LC3, respectively), (ii) the size of the adrenal cortex and medulla (morphometric analysis), (iii) G-protein coupled estrogen receptor (GPER) and estrogen-related receptors (ERRs; type α, ß, and Y) distribution and expression (qRT-PCR and immunohistochemical analyses) and (iv) serum testosterone and estradiol levels (immunoassay ELISA). This study revealed pre-rut characteristics of testis structure with the presence of both senescence and autophagy-positive cells and higher involvement of senescence, especially in spermatogenic cells (P < 0.05). In the adrenal cortex, groups of cells exhibiting shrinkage were observed. The presence of ERRs in cells of the seminiferous epithelium and interstitial Leydig cells and GPER presence distinctly in Leydig cells was revealed. In adrenals, these receptors were localized in groups of normal-looking cells and those with shrinkage. Morphometric analysis showed differences in cortex width which was smaller (P < 0.05) than that of the medulla. A weak immunohistochemical signal was observed for ERRß when compared to ERRα and ERRγ. The mRNA expression level of ERRα and ERRγ was lower (P < 0.001 and P < 0.05, respectively) while ERRß was higher (P < 0.001) in adrenals when compared to testes. mRNA GPER expression was similar in both glands. In the pre-rut season, the testosterone level was 4.89 ng/ml while the estradiol level was 0.234 ng/ml. We postulate that: (i) senescence and autophagy may be involved in both reinitiation of testis function and/or induction of abnormal processes, (ii) hormonal modulation of testis inactivity may affect adrenal cortex causing cell shrinkage, (iii) ERRs and GPER localization in spermatogenic cells and interstitial cells, as well as cortex cells, may maintain and control the morpho-functional status of both glands, and (iv) androgens and estrogens (via ERRs and GPER) drive cellular processes in the testis and adrenal pre-rut physiology.
Assuntos
Cervos , Testículo , Masculino , Animais , Testículo/metabolismo , Receptores de Estrogênio/genética , Cervos/fisiologia , Testosterona , Estrogênios/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Glândulas Suprarrenais , Autofagia , RNA Mensageiro/metabolismo , Estradiol/metabolismoRESUMO
The concentrations of polonium 210Po and radio-lead 210Pb in cannabis (Cannabis sativa L.) plants and products now legally available in Poland were determined. Limiting the delivery of radionuclides to the body is an important aspect of civil protection in many countries. Reduction in use and awareness of the risks associated with tobacco and cannabis smoking have a great impact. The 210Po and 210Pb concentrations in 44 hemps, 20 hashish and 8 hemp tea samples, as well as in 3 types of cannabis plants (highest parts of mature hemp plant Fenola, Fedora and Futura) were determined. Each of the sample names means a different type and cross of C. sativa L. Being numerous, the are recognized on the market precisely by these names. Effective doses were calculated and compared to the doses of the other combustion products, such as tobacco. In the case of hemp, the highest concentration of 210Po was found in samples of dried Sweet Carmel (34.7 ± 0.23 mBq·g-1), while the lowest in the Hemp Berry (0.57 ± 0.23 mBq·g-1). In the case of 210Pb, the highest concentration was in Strawberry Kush (2.32 ± 0.05 mBq·g-1), while the lowest in Strawberry Haze (0.19 ± 0.03 mBq·g-1). In hashish, the highest and lowest concentrations of 210Po were in Strawberry Diesel 164 ± 3 mBq·g-1 and in Mango Kush 2.5 ± 0.2 mBq·g-1. The highest and lowest concentrations in the case of 210Pb in hashish were in Pollen Hashish 45.1 ± 0.2 mBq·g-1 and in Mango Kush Hashish 0.45 ± 0.05 mBq·g-1, respectively. These radionuclides did not constitute a radioactive equilibrium (210Po/210Pb).
Assuntos
Cannabis , Polônio , Monitoramento de Radiação , Chumbo , Radioisótopos de Chumbo/análise , Polônio/análise , Monitoramento de Radiação/métodosRESUMO
This article contains and discusses the results of research on the source of polonium 210Po and radio-lead 210Pb in the human body of adults living in Poland. An adult inhabitant of Poland receives an effective annual radiation dose of 309 µSv from inhalation and absorption of 210Po and 210Pb. The main sources of both radionuclides in the body is cigarette and marijuana smoking. In terms of food, the consumption of fish, cereals, vegetables and fruit as well as mushrooms have the largest contribution to annual dose. This study highlights the importance of cigarette smoking and the growing importance of marijuana hash smoking as the main source of 210Po and 210Pb for adults living in Poland. The calculated dose that results from the decay of both radionuclides in body is 1/10 of the annual radiation dose received by a Polish inhabitant from natural sources (2.8 mSv) and is almost five times lower than the dose resulting from the inhalation of 222Rn.
Assuntos
Polônio , Monitoramento de Radiação , Animais , Corpo Humano , Humanos , Chumbo , Radioisótopos de Chumbo/análise , Polônia , Polônio/análise , Monitoramento de Radiação/métodosRESUMO
In this study, we propose a new approach in the anterior cruciate ligament (ACL) replacement to provide stability and integration with bone tunnel. A polylactide (PLA)-based tubular implant was used to support the graft stabilization in femoral and tibial bones and to stimulate the healing process after (ACL) replacement on a sheep model. The ACL was replaced with an autologous Achilles tendon split graft. The tendon-to-bone healing in the model was analyzed after 6 and 12 weeks. Two groups of animals were compared, i.e. the group with the PLA-based implant used in the ACL replacement and the control group without the implant. The knee joints were mechanically and clinically evaluated, including the histopathology tests, to determine their stability and integrity. The results indicated that the bioresorbable PLA-based tubular implant may facilitate integration of the tendon graft with bone. Remodeling the allograft inside the implant improves the joint mobility from the first week of healing: no pathological changes were observed at the surgery site and in the animals' mobility. After 6 and 12 weeks of healing no significant changes in the mechanical parameters of the knee joint were observed, regarding the joint failure force, knee displacement, angular mobility range and joint stiffness. Relatively small values of the non-destructive tests in the knee displacement, already 6 weeks after surgery, indicated the early stabilization of the knee joint. The studies showed that the failure forces of knee joints after the ACL replacement with the PLA-based implant are lower than those of an intact joint, although their biomechanical features, including strain-at- failure, are similar. The biomechanical parameters of the knee joint were significantly improved due to the selected method of attaching the autograft ends to the femoral and tibial bone surfaces. After 12 weeks the intra-tunnel tendon-bone site with the PLA implant revealed the better tibia-femur joint mechanical stability, linear force-strain function and the decreasing strain-to-failure value, as compared to the control group.
Assuntos
Tendão do Calcâneo , Ligamento Cruzado Anterior , Animais , Ligamento Cruzado Anterior/cirurgia , Autoenxertos , Articulação do Joelho/cirurgia , Poliésteres , OvinosRESUMO
In this study we aimed to assess the in vivo osteoinductive properties of two composite scaffolds made of PLGA (poly-L-lactide-co-glycolide) and two types of gel-derived bioactive glasses, namely a high silica S2 bioactive glass (S2-PLGA composites) or high lime A2 bioactive glass (A2-PLGA composites). To achieve that, the potential of the composites to induce ectopic bone formation in a rabbit muscle has been examined along with the control PLGA scaffold. Cylinder-like scaffolds of 7 × 3 mm (width × height) were implanted into pouches created in the latissimus dorsi muscle of 18 New Zealand rabbits. The tissue sections were obtained at 6, 12 or 24 weeks post-surgery (six rabbits per each time point) and stained with hematoxylin-eosin. The process of wound healing, the formation of collagen-rich connective tissue and its transition to cartilage were examined by Sirius red and Alcian blue histological stainings. We also performed immunohistochemical verification of the presence of osteoblast- and osteoclast- like cells in the vicinity of the scaffolds. A typical foreign body reaction and wound healing process was observed for all implanted scaffolds. Osteoblast- and osteoclast-like cells were observed in the vicinity of the scaffolds as determined by the immunohistochemical staining for Osteocalcin, BMP-2 and Cathepsin K. Compared to plain PLGA scaffolds, numerous osteoblast-like cells were observed 12 weeks post implantation near the composites and the scaffolds gradually degraded as bone formation proceeded. S2-PLGA and A2-PLGA composites display osteoinductive properties in vivo. Furthermore, they are more effective at inducing ectopic bone formation in a rabbit muscle compared to plain PLGA. Thus these SBG-PLGA composite scaffolds have potential for clinical applications in dental and/or orthopedic-bone tissue engineering.
Assuntos
Substitutos Ósseos/química , Ácido Láctico/química , Músculo Esquelético/citologia , Osteogênese , Ácido Poliglicólico/química , Animais , Proteína Morfogenética Óssea 2/metabolismo , Catepsina K/metabolismo , Vidro/química , Teste de Materiais , Modelos Biológicos , Músculo Esquelético/metabolismo , Osteoblastos/citologia , Osteoblastos/metabolismo , Osteocalcina/metabolismo , Osteoclastos/citologia , Osteoclastos/metabolismo , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Coelhos , Engenharia Tecidual , Alicerces Teciduais/químicaRESUMO
PURPOSE: The purpose of the study was to assess the biocompatibility of porous terpolymer (polytetrafluoroethylene-co-polyvinylidene fluoride-co-polypropylene, PTFE-PVDF-PP) membranes as an implant material to be placed during nonpenetrating very deep sclerectomy (NPVDS). Another study objective was to determine whether the polymer membrane under investigation could be used to manufacture a new-generation implant, which would actively delay the process of fistula closure and facilitate aqueous humor drainage. METHODS: Histological response and tissue tolerance of the implant material were assessed. The study was performed on 38 eyeballs of 19 New Zealand white rabbits (19 implanted, 19 control). Histological assessment was carried out between 2 and 52 weeks after surgery. We routinely assessed inflammatory infiltrate, neovascularization, hemorrhage, and stromal edema as well as connective tissue attachment to the implant and adjacent tissues. RESULTS: At 52 weeks of observation, a statistically significant difference was revealed between the study and control groups in terms of resorptive granulation, tissue, and the inflammatory infiltrate. No features of acute inflammatory response to the implant were observed, and there was an absence of histological features of acute inflammatory infiltrates and subsidence of chronic inflammatory infiltrates and resorptive granulation over time. CONCLUSIONS: Slight fibrotic response and insignificant changes in neighboring eye tissues all indicate good tolerance to bioimplant materials. This allows for some optimism regarding the use of hydrophobic terpolymer in the construction of new intrascleral implants. However, the ultimate decision regarding its usefulness and safety in the treatment of glaucoma requires further investigation.
Assuntos
Materiais Biocompatíveis , Implantes para Drenagem de Glaucoma , Glaucoma/patologia , Pressão Intraocular , Compostos Organofosforados/química , Polímeros/química , Esclera/patologia , Esclerostomia/métodos , Animais , Modelos Animais de Doenças , Glaucoma/fisiopatologia , Glaucoma/cirurgia , Teste de Materiais , Desenho de Prótese , Coelhos , Esclera/cirurgiaRESUMO
The aim of the work was to evaluate the in vivo biological behaviour of polymeric membrane materials for glaucoma implants. The base material was biostable synthetic terpolymer (PTFE-PVDF-PP) with proved biocompability (PN-EN ISO 10993). The samples manufactured in the form a membrane were subjected to chemical and physical treatment to create an open pore system within the polymer matrix. As a porogenic phase biodegradable natrium alginate in a fibrous form was employed. The non-perforating deep sclerectomy technique was performed in a rabbit model. The clinical observations were made after 14 and 30 days. During the study clinical symptoms of a moderate degree were observed, and histopathological changes were typical for foreign body implantation. At the end stage of the study no significant difference in histopathological assessment was found between control and experimental group. Similarities observed in both groups and relatively mild histopathological changes in the tissue surrounding the implant indicate that the observed symptoms come from a deep scleral trauma caused by surgery, and not by the presence of the implant itself.