Evidence for the role of calcineurin in morphogenesis and calcium homeostasis during mycelium-to-yeast dimorphism of Paracoccidioides brasiliensis

Paracoccidioides brasiliensis is a dimorphic fungus that causes paracoccidioidomycosis, the most prevalent human deep mycosis in Latin America. The dimorphic transition from mycelium to yeast (M-Y) is triggered by a temperature shift from 25°C to 37°C and is critical for pathogenicity. Intracellular Ca 2+ levels increased in hyphae immediately after temperature-induced dimorphism. The chelation of Ca 2+ with extracellular (EGTA) or intracellular (BAPTA) calcium chelators inhibited temperature-induced dimorphism, whereas the addition of extracellular Ca 2+ accelerated dimorphism. The calcineurin inhibitor cyclosporine A (CsA), but not tacrolimus (FK506), effectively decreased cell growth, halted the M-Y transition that is associated with virulence, and caused aberrant growth morphologies for all forms of P. brasiliensis. The difference between CsA and FK506 was ascribed by the higher levels of cyclophilins contrasted to FKBPs, the intracellular drug targets required for calcineurin suppression. Chronic exposure to CsA abolished intracellular Ca 2+ homeostasis and decreased mRNA transcription of the CCH1 gene for the plasma membrane Ca 2+ channel in yeast-form cells. CsA had no detectable effect on multidrug resistance efflux pumps, while the effect of FK506 on rhodamine excretion was not correlated with the transition to yeast form. In this study, we present evidence that Ca 2+/calmodulin-dependent phosphatase calcineurin controls hyphal and yeast morphology, M-Y dimorphism, growth, and Ca 2+ homeostasis in P. brasiliensis and that CsA is an effective chemical block for thermodimorphism in this organism. The effects of calcineurin inhibitors on P. brasiliensis reinforce the therapeutic potential of these drugs in a combinatory approach with antifungal drugs to treat endemic paracoccidioidomycosis. Copyright © 2008, American Society for Microbiology. All Rights Reserved.

BMP implant associated with platelet-rich plasma in orbit fracture repair

Purpose: To evaluate a bone morphogenetic protein (BMP) implant with and without platelet-rich plasma (PRP), which is supposed to accelerate fracture consolidation in the orbit fracture treatment. Methods: Thirty-six white rabbits were subjected to orbital fracture and treated in three groups: BMP implant fracture repair (G1), BMP plus PRP implant fracture repair (G2), and fracture and spontaneous repair (G3). The animals were sacrificed at 7, 30, 90, and 180 days after surgery. A radiology evaluation was carried out on the 7th day after the fracture and at the sacrifice moments. After the animals' death, the orbital content material was removed and prepared for morphological and morphometric analysis. Results: Radiology suggested intramembranous and progressive cavitation and ossification without a reduction in implant size and with signs of calcium deposition; these events were confirmed by histological analysis, which showed a lymphomononuclear inflammatory reaction in G1 and G2, more intense 7 days after surgery and reducing after 30 days. Associating PRP with BMP did not accelerate bone induction. Conclusion: BMP implant promotes bone induction, integration at fracture site, scarce inflammatory reaction, and may be a good alternative in orbit fracture reconstruction. The addition of PRP to the BMP plate did not accelerate the resolution, and its use is not necessary. Copyright © Informa Healthcare USA, Inc.

A human retrieval study of plasma-sprayed hydroxyapatite-coated plateau root form implants after 2 months to 13 years in function

Calcium phosphate-based bioactive ceramics in various physical and chemical formulations have been extensively utilized as biomaterials for bone regeneration/conduction. However, the determination of their in vivo temporal behavior from the short to long term in humans has been a challenge due to the lack of physical reference for morphologic and morphometric evaluation. The present study evaluated bone morphology and morphometry (bone-to-implant contact [BIC]) around plasma-sprayed hydroxyapatite (PSHA)-coated endosseous implants that were retrieved due to prosthetic reasons while successfully in function at the posterior region of the jaws from as early as 2 months to ~13 years after a 6-month healing period after placement. Bone morphology was evaluated by light microscopy, and BIC was determined using computer software. Irrespective of the time in vivo, lamellar bone was observed in close contact with the implant PSHA-coated surface and between plateaus. BIC ranged from ~35-95%, was highly directional, and Haversian-like osteonic morphology between plateaus was observed for most implants. The PSHA coating was present with little variation in thickness between the samples retrieved regardless of time in vivo. © 2010 by Begell House, Inc.

Osseointegration assessment of chairside argon-based nonthermal plasma-treated Ca-P coated dental implants

This study investigated the effect of an Argon-based nonthermal plasma (NTP) surface treatment-operated chairside at atmospheric pressure conditions applied immediately prior to dental implant placement in a canine model. Surfaces investigated comprised: Calcium-Phosphate (CaP) and CaP + NTP (CaP-Plasma). Surface energy was characterized by the Owens-Wendt-Rabel-Kaelble method and chemistry by X-ray photoelectron spectroscopy (XPS). Six adult beagles dogs received 2 plateau-root form implants (n = 1 each surface) in each radii, providing implants that remained 1 and 3 weeks in vivo. Histometric parameters assessed were bone-to-implant contact (BIC) and bone area fraction occupancy (BAFO). Statistical analysis was performed by Kruskall-Wallis (95% level of significance) and Dunn's post-hoc test. The XPS analysis showed peaks of Ca, C, O, and P for the CaP and CaP-Plasma surfaces. Both surfaces presented carbon primarily as hydro-carbon (CAC, CAH) with lower levels of oxidized carbon forms. The CaP surface presented atomic percent values of 38, 42, 11, and 7 for C, O, Ca, and P, respectively, and the CaPPlasma presented increases in O, Ca, and P atomic percent levels at 53, 12, and 13, respectively, in addition to a decrease in C content at 18 atomic percent. At 1 week no difference was found in histometric parameters between groups. At 3 weeks significantly higher BIC and BAFO were observed for CaPPlasma treated surfaces. Surface elemental chemistry was modified by the Ar-based NTP. Ar-based NTP improved bone formation around plateau-root form implants at 3 weeks compared with CaP treatment alone. © 2012 Wiley Periodicals, Inc.

Improvements of plasma immersion ion implantation (PIII) and deposition (PIII&D) processing for materials surface modification

Plasma immersion ion implantation (PIII) process is a three dimensional surface modification method that is quite mature and well known to the surface engineering community nowadays, especially to those working in the field of plasma-materials interaction, aiming at both industrial and academic applications. More recently, deposition methods have been added to PIII, the PIII&D, opening possibilities of broader range of applications of these techniques. So, PIII&D is becoming a routine method of surface modification, with the advantage of pushing up the retained dose levels limited by the sputtering due to ion implantation. Therefore, well adherent, thick, three-dimensional films without stress are possible to be achieved, at relatively low cost, using PIII&D. In this paper, we will discuss about a few PIII and PIII&D experiments that have been performed recently to achieve surface improvements in different materials: 1 - high temperature nitrogen PIII in Ti6Al4V alloy in which a deep nitrogen rich treated layer resulted in surface improvements as increase of hardness, corrosion resistance and resistance to wear of the Ti alloy; 2 - nanostructures in ZnO films, obtained by PIII&D of vaporized & ionized Zn source; 3 - combined implantation and deposition of calcium for biomaterial activity of Ti alloy (PIII&D), allowing the growth of hydroxyapatite in a body solution; 4 - magnetron sputtering deposition of Cr that was enhanced by the glow discharge Ar plasma to allow implantation and deposition of Cr on SAE 1070 steel (PIII&D) resulting in surfaces with high resistance to corrosion; and 5 - implantation of nitrogen by ordinary PIII into this Cr film, which improved resistance to corrosion, while keeping the tribological properties as good as for the SAE 1070 steel surface. © 2012 Elsevier B.V.

Avaliação dos parâmetros espermáticos e caracterização do perfil bioquímico do plasma seminal de cães (Canis familiaris – LINNAEUS, 1758) com hiperplasia prostática benigna, tratados com toxina botulínica A

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Caracterização eletroforética do perfil protéico e análise bioquímica do plasma seminal canino

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Associação do plasma rico em plaquetas, novo vidro bioativo e sulfato de cálcio no tratamento de defeitos de furca classe II: estudo histológico e histométrico em cães

Pós-graduação em Odontologia - FOA

Semen parameters and seminal plasma protein and biochemical profiles of dogs with benign prostatic hyperplasia after botulinum toxin type A intraprostatic injection

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effects of calcium salts of soybean oil on factors that influence pregnancy establishment in Bos indicus beef cows

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Down-regulation of SLC8A1 as a putative apoptosis evasion mechanism by modulation of calcium levels in penile carcinoma

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Padronização de técnica manual para obtenção de plasma rico em plaquetas de bovino

To evaluate the biochemical profile and protein concentration of whey from milk samples of healthy Murrah primiparous and pluriparous buffaloes, 30 female buffaloes were analyzed during a complete lactation. The animals were divided into three groups: G1 = 10 primiparous buffaloes, G2 = 10 pluriparous buffaloes with 2-3 lactations and G3 = 10 pluriparous buffaloes with > 3 lactations. The lactation period was divided into: early stage (I: 1-3 months of lactation), intermediate stage (T: 4-6 months of lactation) and final stage (F: 7-9 months of lactation). Before milk sampling, physical examination of the mammary gland, strip cup test and California Mastitis Test (CMT) were performed. After mammary quarters asepsis, 20mL of milk were collected monthly from each mammary quarter, during a complete lactation, in sterilized plastic bottles without preservative, in order to perform microbiological isolation, biochemical profile and protein electrophoresis in sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), and 30mL of milk from each mammary quarter were collect, in sterilized plastic bottles containing preservative bronopol to perform the somatic cell count (SCC). A total of 1,042 milk samples were collected from the experimental groups during lactation, of which 923 samples showed negative reaction to CMT and negative microbiological isolation and were selected to biochemical profile analysis and protein electrophoresis in SDS-PAGE. There were influence of parity order and stage of lactation in biochemical profile and protein concentration of healthy Murrah buffaloes'whey. Primiparous buffaloes (G1) showed higher gamma-glutamyltransferase (GGT: 2,346 U/L), alkaline phosphatase (ALP: 181 U/L), phosphorus (P; 56.6mg/dL), potassium (K; 32.0mg/dL) and alpha-lactalbumin (458mg/dL). Buffaloes with 2-3 lactations (G2) showed higher SCC (70,700 cells/mL) and higher concentrations of total protein (1.55g/dL), albumin (100mg/dL), magnesium (Mg; 8.80mg/dL), chlorides (Cl; 176mg/dL), iron (Fe; 10.7 mu g/dL), sodium (Na; 178mMol/L) and lactoferrin (59.5mg/dL). Bufalloes with > 3 lactations (G3) showed higher concentrations of total calcium (Ca; 41.8mg/dL), ionized calcium (iCa; 2.92mMol/L), immunoglobulin A (IgA; 1.32mg/dL), serum albumin (99.1mg/dL), immunoglobulin G (IgG; 49.7mg/dL) and beta-lactoglobulin (1,068mg/dL). During lactation it was observed increase in SCC, GGT, ALP, total protein, albumin, P, Mg, Cl, Na, lactoferrin, serum albumin, IgG and alpha-lactalbumin, as well as decrease in concentrations of Ca, Fe, iCa, K, IgA and beta-lactoglobulin in buffaloes'whey. The results may be used as reference for buffaloes and to support diagnosis and prognosis of diseases common to lactation periods.

Hydroxyapatite coating deposited on grade 4 titanium by plasma electrolytic oxidation

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Homogenous demineralized dentin matrix and platelet-rich plasma for bone tissue engineering in cranioplasty of diabetic rabbits: biochemical, radiographic, and histological analysis

This study evaluated the effects of homogenous demineralized dentin matrix (HDDM) slices and platelet-rich plasma (PRP) in surgical defects created in the parietal bones of alloxan-induced diabetic rabbits, treated with a guided bone regeneration technique. Biochemical, radiographic, and histological analyses were performed. Sixty adult New Zealand rabbits were divided into five groups of 12: normoglycaemic (control, C), diabetic (D), diabetic with a PTFE membrane (DM), diabetic with a PTFE membrane and HDDM slices (DM-HDDM), and diabetic with PTFE membrane and PRP (DM-PRP). The quantity and quality of bone mass was greatest in the DM-HDDM group (respective radiographic and histological analyses: at 15 days, 71.70±16.50 and 50.80±1.52; 30 days, 62.73±16.51 and 54.20±1.23; 60 days, 63.03±11.04 and 59.91±3.32; 90 days, 103.60±24.86 and 78.99±1.34), followed by the DM-PRP group (respective radiographic and histological analyses: at 15 days 23.00±2.74 and 20.66±7.45; 30 days 31.92±6.06 and 25.31±5.59; 60 days 25.29±16.30 and 46.73±2.07; 90 days 38.10±14.04 and 53.38±9.20). PRP greatly enhanced vascularization during the bone repair process. Abnormal calcium metabolism was statistically significant in the DM-PRP group (P<0.001) for all four time intervals studied, especially when compared to the DM-HDDM group. Alkaline phosphatase activity was significantly higher in the DM-HDDM group (P<0.001) in comparison to the C, D, and DM-PRP groups, confirming the findings of intense osteoblastic activity and increased bone mineralization. Thus, HDDM promoted superior bone architectural microstructure in bone defects in diabetic rabbits due to its effective osteoinductive and osteoconductive activity, whereas PRP stimulated angiogenesis and red bone marrow formation.

Avaliação da bioatividade de revestimentos produzidos sobre Tântalo por oxidação eletrolítica assistida por plasma

Pós-graduação em Ciência e Tecnologia de Materiais - FC