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1.
Protoplasma ; 261(3): 487-496, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38052957

RESUMO

The importance and regulation of adrenal androgen production and signaling are not completely understood and are scarcely studied. In addition, there is still a search for appropriate animal models and experimental systems for the investigation of adrenal physiology and disease. Therefore, the main objective of the study was to evaluate the effect of luteinizing hormone (LH) signaling and selenium (Se2+) exposure on androgen adrenal signaling via canonical androgen receptor (AR), and membrane androgen receptor acting as zinc transporter (zinc- and iron-like protein 9; ZIP9). For herein evaluations, adrenals isolated from transgenic mice with elevated LH receptor signaling (KiLHRD582G) and adrenals obtained from rabbits used for ex vivo adenal cortex culture and exposure to Se2+ were utilized. Tissues were assessed for morphological, morphometric, and Western blot analyses and testosterone and zinc level measurements.Comparison of adrenal cortex histology and morphometric analysis in KiLHRD582G mice and Se2+-treated rabbits revealed cell hypertrophy. No changes in the expression of proliferating cell nuclear antigen (PCNA) were found. In addition, AR expression was decreased (p < 0.001) in both KiLHRD582G mouse and Se2+-treated rabbit adrenal cortex while expression of ZIP9 showed diverse changes. Its expression was increased (P < 0.001) in KiLHRD582G mice and decreased (P < 0.001) in Se2+-treated rabbits but only at the dose 10 ug/100 mg/ tissue. Moreover, increased testosterone levels (P < 0.05) and zinc levels were detected in the adrenal cortex of KiLHRD582G mice whereas in rabbit adrenal cortex treated with Se2+, the effect was the opposite (P < 0.001).


Assuntos
Córtex Suprarrenal , Selênio , Camundongos , Animais , Coelhos , Androgênios , Receptores Androgênicos/metabolismo , Receptores do LH , Selênio/farmacologia , Testosterona , Córtex Suprarrenal/metabolismo , Receptores Acoplados a Proteínas G , Zinco
3.
J Environ Radioact ; 268-269: 107259, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37523833

RESUMO

The article recounts the discovery of the development of polonium chemistry. The development of its chemistry and the discovery of its properties and uses, both useful and criminal. In addition, it provides biographical details of its discoverers and the scientists who systematically uncovered its secrets.


Assuntos
Polônio , Monitoramento de Radiação , Aniversários e Eventos Especiais
4.
Molecules ; 28(1)2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36615640

RESUMO

This study aimed at assessing the activity concentration and the annual effective dose of polonium-210 (210Po) in fruit wines derived from four locations in Poland (Warmian−Masurian, Podlaskie, Lubelskie and Malopolskie voivodeships). The fruit wines differed significantly (p < 0.05) in 210Po activity depending on the production site, with the Malopolskie site having the highest activity (61.4−221.4 mBq/L) and the Podlaskie having the lowest (3.5−97.1 mBq/L). The site differentiation was due to environmental conditions­soil parameters (uranium concentration), precipitations and terrain characteristics, e.g., the proximity of the lakes. The increased activity concentration of 210Po in samples from Malopolska compared with the other sites probably derived from the environment polluted with aqueous wastes and particulate air pollution. The annual effective dose due to the ingestion of fruit wines ranged from 0.112 to 1.214 µSv/year. These levels of exposure are safe according to the WHO criterion (0.1 mSv per year for ingestion) and to the IAEA reference level for public exposure including food (1 mSv per year). Summing up, the data obtained provide information on the activity concentration of 210Po in fruit wines and increase databases on the natural radioactivity of foodstuffs. Future work is needed to examine 210Po activity in samples from all vineyard regions in Poland.


Assuntos
Polônio , Monitoramento de Radiação , Vinho , Polônio/análise , Frutas/química , Polônia
5.
Theriogenology ; 198: 141-152, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36586352

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/metabolismo
6.
J Environ Radioact ; 246: 106834, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35158283

RESUMO

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/métodos
7.
Artigo em Inglês | MEDLINE | ID: mdl-35206170

RESUMO

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/métodos
8.
Stem Cell Rev Rep ; 18(2): 672-690, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34782949

RESUMO

In this work we dissected the osteoinductive properties of selected, PLGA-based scaffolds enriched with gel-derived bioactive glasses (SBGs) of either binary SiO2-CaO or ternary SiO2-CaO-P2O5 system, differing in CaO/SiO2 ratio (i.e. high -or low-calcium SBGs). To assess the inherent ability of the scaffolds to induce osteogenesis of human bone marrow stromal cells (BMSC), the study was designed to avoid any osteogenic stimuli beyond the putative osteogenic SBG component of the studied scaffolds. The bioactivity and porosity of scaffolds were confirmed by SBF test and porosimetry. Condition media (CM) from BMSC-loaded scaffolds exhibited increased Ca and decreased P content corresponding to SBGs CaO/SiO2 ratio, whereas Si content was relatively stable and overall lower in CM from scaffolds containing binary SBGs. CM from cell-loaded scaffolds containing high-calcium, binary SBGs promoted migration of BMSC and BMP-response in reporter osteoblast cell line. BMSC culture on these scaffolds or the ones containing ternary, low-calcium SBGs resulted in the activation of BMP-related signaling and expression of several osteogenic markers. Ectopic bone formation was induced by scaffolds containing binary SBGs, but high-calcium ones produced significantly more osteoid. Scaffolds containing ternary SBGs negatively influenced the expression of osteogenic transcription factors and Cx43, involved in cell-cell interactions. High-calcium scaffolds stimulated overall higher Cx43 expression. We believe the initial cell-cell communication may be crucial to induce and maintain osteogenesis and high BMP signaling on the studied scaffolds. The presented scaffolds' biological properties may also constitute new helpful markers to predict osteoinductive potential of other bioactive implant materials.


Assuntos
Materiais Biocompatíveis , Vidro , Materiais Biocompatíveis/farmacologia , Movimento Celular , Humanos , Osteogênese , Dióxido de Silício/farmacologia
9.
J Mech Behav Biomed Mater ; 125: 104923, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34753103

RESUMO

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 , Ovinos
10.
Isotopes Environ Health Stud ; 57(6): 623-631, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34783613

RESUMO

Milk has been known for its nutritional properties for centuries and is often the staple of the diet in many countries. Therefore, monitoring of milk composition seems to be a relevant task as it was the purpose of this study to compare levels of 210Po and 210Pb in several Polish voivodeships. The methodology was based on mineralization, loss on an inorganic matrix and concentration measurement on an alpha spectrometer. The concentrations of 210Po and 210Pb in collected milk samples were measured using alpha spectrometry and calculations, respectively. The results showed that the lowest concentration of 210Po is 2.8 ± 0.2 mBq l-1 and the highest is 56.3 ± 0.7 mBq l-1 while the 210Pb concentrations are in the range from 2.8 ± 0.2 to 44.0 ± 1.7 mBq l-1. The associated annual effective doses for adults jmrange from 3.5 ± 0.1 to 11.0 ± 0.2 µSv a-1 for 210Po and from 2.0 ± 0.1 to 5.0 ± 0.1 µSv a-1 for 210Pb. The lowest doses were noticed in Kuyavian-Pomeranian Voivodeship and the highest values were found in Lesser Poland Voivodeship. The results show that the annual effective dose in individual provinces is not dangerous to health. However, there are significant differences between highly and lowly industrialized voivodeships.


Assuntos
Radioisótopos de Chumbo , Monitoramento de Radiação , Animais , Bovinos , Feminino , Chumbo , Radioisótopos de Chumbo/análise , Leite/química , Polônia , Polônio
11.
J Environ Radioact ; 222: 106376, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32861138

RESUMO

In 2017, the Polish public consumed on average 0.61 kg of honey, while the European average consumption was 0.7 kg (Data on honey consumption in Poland, 2014) [http://www.portalspozywczy.pl]. The main point of this study was to investigate the 210Po activity concentrations in different types of floral and non-floral honey, type of clad honey is made of and honey yield in honey available on the Polish market. Activity of 210 Po in honey ranged from 0.006 ± 0.001 to 0.384 ± 0.004 Bq kg-1 with effective dose 0.005 ± 0.001 to 0.281 ± 0.003 µSv/year. The activity in honey was measured by alpha-spectrometry. The concentration of radionuclide depends on the raw material used by bees and plant type. The highest concentration of 210Po was observed in the honeydew honey and herbal honey.


Assuntos
Mel , Monitoramento de Radiação , Radioatividade , Animais , Polônia , Radioisótopos
12.
Animals (Basel) ; 10(4)2020 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-32290243

RESUMO

The laparoscopic method of recovering oocytes in goats and sheep is one of the minimally invasive methods used in the biotechnology of animal reproduction. It allows for good quality oocytes that are suitable for in vitro maturation and fertilization to be recovered. The limitation of using the laparoscopic ovum pick-up (L-OPU) method in goat and sheep is its changing effectiveness and the lack of repeatability of results, as well as the varying effectiveness of different variants of the method. Therefore, it is necessary to develop effective non-invasive techniques allowing for multiple good quality oocyte recovery that would be suitable for in vitro maturation and fertilization. In this study, four different L-OPU variants were described in goats and sheep. Various techniques of recovering oocytes were discussed, including the techniques of conducting the operation, various tools for recovering oocytes, and different plans of hormonal stimulation. Recovery rates were 35% (Variant I), 57% (Variant II), 72% (Variant III), and 67% (Variant IV). After evaluation, 94% (both Variant I and II), 93% (Variant III), and 84% (Variant IV) of the oocytes were qualified for in vitro maturation. The results of the study show that the proposed technique of laparoscopic recovery of oocytes allows a sufficient number of ovarian cells suitable for in vitro culture to be obtained and as a consequence it makes them useful in in vitro maturation/in vitro fertilization (IVM/IVF) programs or cloning. The method allows for a fast and effective conduct of the operation in a living donor with minimal invasiveness while preserving the excellent condition of animals.

13.
Polymers (Basel) ; 11(12)2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31795412

RESUMO

The exact causes of failure of anterior cruciate ligament (ACL) reconstruction are still unknown. A key to successful ACL reconstruction is the prevention of bone tunnel enlargement (BTE). In this study, a new strategy to improve the outcome of ACL reconstruction was analyzed using a bioresorbable polylactide (PLA) stent as a catalyst for the healing process. The study included 24 sheep with 12 months of age. The animals were randomized to the PLA group (n = 16) and control group (n = 8), subjected to the ACL reconstruction with and without the implantation of the PLA tube, respectively. The sheep were sacrificed 6 or 12 weeks post-procedure, and their knee joints were evaluated by X-ray microcomputed tomography with a 50 µm resolution. While the analysis of tibial and femoral tunnel diameters and volumes demonstrated the presence of BTE in both groups, the enlargement was less evident in the PLA group. Also, the microstructural parameters of the bone adjacent to the tunnels tended to be better in the PLA group. This suggested that the implantation of a bioresorbable PLA tube might facilitate osteointegration of the tendon graft after the ACL reconstruction. The beneficial effects of the stent were likely associated with osteogenic and osteoconductive properties of polylactide.

14.
Biomed Mater ; 12(1): 015015, 2017 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-28094240

RESUMO

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/química
15.
Acta Bioeng Biomech ; 17(3): 23-31, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26687296

RESUMO

PURPOSE: The aim of the study was to evaluate the influence of an implant made of a terpolymer (PTFE-PVDF-PP) on the condition of rabbit eyes during a one year observation period. METHODS: The implant in the shape of an equilateral triangle (3 mm side length) was manufactured from a thin hydrophobic porous membrane. There were evaluated 40 eyes of 20 rabbits. The animals had non-penetrating very deep sclerectomy (NPVDS) performed, with insertion of an implant in the form of a triangular thin membrane. The control group consisted of 20 eyes where the animals had NPVDS performed without implant insertion. The evaluations included the study of the anterior part of the eye together with photographic documentation. Histopathological examination of the eyes 52 weeks after NPVDS procedure has been made. The process of wound healing was comparable in both groups. RESULTS: The evaluation of the rabbits did not reveal any acute process of intraocular inflammation. After 12 month period of observation, no statistically significant differences in the process of wound healing or status of eyes were found between the groups. An analysis of fibrous connective tissue attachment to the implant showed that its layer was not thick and did not differ significantly from the control. The procedure of very deep sclerectomy and insertion of a polymer implant were well tolerated by the rabbit eyes. CONCLUSIONS: The in vivo results indicate that the hydrophobic implant in the form of a membrane can serve as a sclera implant after further study.


Assuntos
Interações Hidrofóbicas e Hidrofílicas , Implantes Experimentais , Polímeros/farmacologia , Esclera/efeitos dos fármacos , Esclera/cirurgia , Animais , Perda Sanguínea Cirúrgica , Corpo Ciliar/cirurgia , Pressão Intraocular , Modelos Animais , Porosidade , Coelhos , Esclera/patologia , Esclera/fisiopatologia
16.
Invest Ophthalmol Vis Sci ; 56(9): 5203-9, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26244296

RESUMO

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/cirurgia
17.
J Mater Sci Mater Med ; 21(10): 2843-51, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20652824

RESUMO

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.


Assuntos
Materiais Biocompatíveis/química , Glaucoma/cirurgia , Animais , Reação a Corpo Estranho/etiologia , Reação a Corpo Estranho/patologia , Glaucoma/patologia , Humanos , Teste de Materiais , Membranas Artificiais , Modelos Animais , Politetrafluoretileno/química , Polivinil/química , Próteses e Implantes , Coelhos , Esclera/patologia , Esclera/cirurgia , Esclerostomia/métodos
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