27 resultados para OSSEOUS SUBSTITUTE
em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo
Resumo:
A 6mm segmental defect was performed on the metaphyseal region of the tibia of 12 rabbits and the autoclaved fragmented heterolog cortical bone conserved in glycerin (98%) and methylmethacrylate was used as a bone graft for the reconstruction. The graft was placed in the receptor bed and its integration was evaluated by computed tomography after 30, 60 and 90 days. There was gradual bone graft incorporation in the receptor bed during the time in 100% of the cases. Fragmented cortical bone heterograft and methylmethacrylate was biologically compatible and promotes bone defect reparation without signs of infection, migration and or rejection, featuring a new option of osseous substitute to fill in bone defects.
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Abstract Introduction Endometrial ossification is an uncommon disease related to secondary infertility and its etiology and pathogenesis are controversial. More than 80% of reported cases occur after pregnancy. Case presentation A 33-year-old Caucasian woman was admitted with a history of secondary infertility and with a regular menstrual cycle. She reported a miscarriage at 12 weeks of gestation 7 years previously and subsequent dilatation and curettage in another medical facility. Vaginal ultrasound was performed and showed an intrauterine structure described as a hyperechogenic image suggesting calcification related to chronic endometritis. Office hysteroscopy revealed a wide endometrial cavity and proliferative endometrium, with a coral-like white plaque 1.5 cm in length on the right horn and posterior wall of the uterus. The lesion was treated by hysteroscopy without complications. Microscopic examination showed endometrial tissue with osseous metaplasia in the stroma. Nine months after the procedure, the patient became pregnant spontaneously. Conclusion In our patient, hysteroscopy was effective in the diagnosis and treatment of osseous metaplasia of the endometrium associated with infertility.
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Objectives: Limbal stem cells (LSC) are self-renewing, highly proliferative cells in vitro, which express a set of specific markers and in vivo have the capacity to reconstruct the entire corneal epithelium in cases of ocular surface injury. Currently, LSC transplantation is a commonly used procedure in patients with either uni- or bilateral total limbal stem cells deficiency (TLSCD). Although LSC transplantation holds great promise for patients, several problems need to be overcome. In order to find an alternative source of cells that can partially substitute LSC in cornea epithelium reconstruction, we aimed at investigating whether human immature dental pulp stem cells (hIDPSC) would present similar key characteristics as LSC and whether they could be used for corneal surface reconstruction in a rabbit TLSCD model. Materials: We used hIDPSC, which co-express mesenchymal and embryonic stem cell markers and present the capacity to differentiate into derivative cells of the three germinal layers. TLSCD was induced by chemical burn in one eye of rabbits. After 30 days, the opaque tissue formed was removed by superficial keratectomy. Experimental group received undifferentiated hIDPSC, while control group only received amniotic membrane (AM). Both groups were sacrificed after 3 months. Results and conclusions: We have demonstrated, using immunohistochemistry and reverse transcription-polymerase chain reaction, that hIDPSCs express markers in common with LSC, such as ABCG2, integrin beta 1, vimentin, p63, connexin 43 and cytokeratins 3/12. They were also capable of reconstructing the eye surface after induction of unilateral TLSCD in rabbits, as shown by morphological and immunohistochemical analysis using human-specific antibodies against limbal and corneal epithelium. Our data suggest that hIDPSCs share similar characteristics with LSC and might be used as a potential alternative source of cells for corneal reconstruction.
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This study evaluated the effects of two lipids sources of fish residue (tilapia and salmon) compared with a vegetable oil source (soybean oil) on the fatty acid profiles of male and female lambari. This experiment was developed in a completely randomized experimental design in a 3 x 2 factorial arrangement, totaling 6 treatments resulting from the combination of the three experimental diets for both sexes, with four replications for each treatment. This study involved 120 male (2.58 +/- 0.13 g) and 72 female lambari (4.00 +/- 0.09 g), fed the experimental diets twice a day until apparent satiation for a period of 60 days. Oleic, linoleic, palmitic and stearic fatty acids were found at higher concentrations in all experimental oils and diets, as well in the muscle of male and female lambari. The low amounts of arachidonic, eicosapentaenoic and docosahexaenoic acids in the experimental diets and subsequent greater concentrations in muscle tissue, suggested that lambari are able to desaturate and elongate the chain of fatty acids with 18 carbons. The fish of both sexes that received the diet with soybean oil showed high levels of n-6 fatty acids, especially of C18: 2n-6 and low levels of eicosapentaenoic and docosahexaenoic acids. The diet with salmon residue oil promoted higher levels of fatty acids of the n-3 series and resulted in the best n-3/n-6 ratio in the muscle of male and female lambari. The oils from fish residues can be a substitute for traditional fish oil and its use in the lambari diets does not impair its growth.
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The stability of the Glossoscolex paulistus hemoglobin (HbGp), in two iron oxidation states (and three forms), as monitored by optical absorption, fluorescence emission and circular dichroism (CD) spectroscopies, in the presence of the chaotropic agent urea, is studied. HbGp oligomeric dissociation, denaturation and iron oxidation are observed. CD data show that the cyanomet-HbGp is more stable than the oxy-form. Oxy- and cyanomet-HbGp show good fits on the basis of a two state model with critical urea concentrations at 220-222 nm of 5.1 +/- 0.2 and 6.1 +/- 0.1 mol/L, respectively. The three-state model was able to reveal a subtle second transition at lower urea concentration (1.0-2.0 mol/L) associated to partial oligomeric dissociation. The intermediate state for oxy- and cyanomet-HbGp is very similar to the native state. For met-HbGp, a different equilibrium, in the presence of urea, is observed. A sharp transition at 1.95 +/- 0.05 mol/L of denaturant is observed, associated to oligomeric dissociation and hemichrome formation. In this case, analysis by a three-state model reveals the great similarity between the intermediate and the unfolded states. Analysis of spectroscopic data, by two-state and three-state models, reveals consistency of obtained thermodynamic parameters for HbGp urea denaturation. (C) 2012 Elsevier Inc. All rights reserved.
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Skeletal tissues of 49 humpback whales Megaptera novaeangliae that stranded between 2002 and 2011 along the Abrolhos Bank seashore and its adjacent waters in Brazil were studied. Twelve (24.5%) animals presented pathological changes in one or more bones. Degenerative changes and developmental malformations were most frequent (10.2% each), followed by inflammatory/infectious and traumatic lesions (8.2% each). Infectious diseases led to severe lesions of the caudal vertebrae of 2 whales. In one of these individuals, the lesions involved 6 caudal vertebrae, leading to ankylosis of 3 vertebrae. Degenerative changes were observed in the vertebral columns of 3 animals, involving the joints of 13 ribs of 1 individual, and in the humerus of 1 whale. Traumatic lesions, such as osseous callus in the ribs, were observed in 4 animals. In 1 whale, the rib showed severe osteomyelitis, possibly resulting from the infection of multiple fractures. Developmental abnormalities such as spina bifida on 3 cervical vertebrae of 1 whale, fusion of spinal processes on thoracic vertebrae of 1 individual and fusion of the first 2 ribs unilaterally or bilaterally in 4 animals were found. Chronic infectious conditions found in the axial skeleton may have restrained spinal mobility and had detrimental effects on the general health of the animals, contributing to stranding and death. To our knowledge, this is the first systematic study on skeletal lesions in stranded humpback whales.
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New technologies and sterilization agents for heat-sensitive materials are under intense investigation. Plasma sterilization, an atoxic low-temperature substitute for conventional sterilization, uses various gases that are activated by an electrical discharge, generating reactive species that promote lethality in microorganisms. Here, assays were performed using pure O-2 and O-2 + H2O2 mixture gas plasmas against a standard load of Bacillus atrophaeus spores inoculated on glass carriers inside PVC catheters. The sterilization efficiency was studied as a function of plasma system (reactive ion etching or inductively coupled plasma), biological monitor lumen diameter, gas, radio frequency power, and sub-lethal exposition time. After sterilization, the biological monitors were disassembled and the surviving bacteria were grown in trypticase soy broth using the most probable number technique. Plasma antimicrobial activity depended on the catheter's internal diameter and radio frequency powers. The N-2 + H2O2 mixture exhibited higher microbial efficacy than pure N-2 in both plasma systems.
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Femtosecond lasers have been widely used in laser surgery as an instrument for contact-free tissue removal of hard dental, restorative materials, and osseous tissues, complementing conventional drilling or cutting tools. In order to obtain a laser system that provides an ablation efficiency comparable to mechanical instruments, the laser pulse rate must be maximal without causing thermal damage. The aim of this study was to compare the different morphological characteristics of the hard tissue after exposure to lasers operating in the femtosecond pulse regime. Two different kinds of samples were irradiated: dentin from human extracted teeth and bovine femur samples. Different procedures were applied, while paying special care to preserving the structures. The incubation factor S was calculated to be 0.788 +/- 0.004 for the bovine femur bone. These results indicate that the incubation effect is still substantial during the femtosecond laser ablation of hard tissues. The plasma-induced ablation has reduced side effects, i.e., we observe less thermal and mechanical damage when using a superficial femtosecond laser irradiation close to the threshold conditions. In the femtosecond regime, the morphology characteristics of the cavity were strongly influenced by the change of the effective number of pulses. (C) 2012 Society of Photo-Optical Instrumentation Engineers (SPIE). [DOI: 10.1117/1.JBO.17.4.048001]
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Potassium fluorrichterite (KNaCaMg5Si8O22F2) glass-ceramics were modified by either increasing the concentration of calcium (GC5) or by the addition of P2O5 (GP2). Rods (2 x 4 mm) of stoichiometric fluorrichterite (GST), modified compositions (GC5 and GP2) and 45S5 bioglass, which was used as the reference material, were prepared using a conventional lost-wax technique. Osteoconductivity was investigated by implantation into healing defects in the midshaft of rabbit femora. Specimens were harvested at 4 and 12 weeks following implantation and tissue response was investigated using computed microtomography (mu CT) and histological analyses. The results showed greatest bone to implant contact in the 45S5 bioglass reference material at 4 and 12 weeks following implantation, however, GST, GC5 and GP2 all showed direct bone tissue contact with evidence of new bone formation and cell proliferation along the implant surface into the medullary space. There was no evidence of bone necrosis or fibrous tissue encapsulation around the test specimens. Of the modified potassium fluorrichterite compositions, GP2 showed the greatest promise as a bone substitute material due to its osteoconductive potential and superior mechanical properties.
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The objective of this study was to evaluate lyophilized bovine colostrum as an alternative source of passive immunity and insulin like growth factor I (IGF-I) for goat kids, considering newborns consuming non-maternal colostrum. Twenty-nine male newborns received 5% of body weight of lyophilized bovine (LBC) or goat colostrum (GC), both with 55 mg/mL of IgG, at 0, 7 and 14 h of life. Blood samples were collected at 0, 7, 14, 18, 24, 36, 48, 72 and 96 h of life to determine serum IgG, total protein (TP), IGF-I and apparent efficiency of IgG absorption at 7, 14, 18 and 24 h (AEA(7hr), AEA(14hr), AEA(18hr), AEA(total), respectively). In LBC, the values of serum IgG at 14, 18,24 and 48 h (13.1, 13.4, 14.1 and 14.6 mg/mL, respectively) were higher than the values at 0 and 7 h (0.04 and 6.9 mg/mL, respectively). In GC, the serum IgG at 18 h (9.3 mg/mL) was higher than the value at 7 h (5.5 mg/mL). AEA(7hr) and AEA(14hr) in LBC were the same (19.2 and 18.5%, respectively, P>0.05) and the values of AEA(18hr) and AEA(total), 9.3 and 9.5%, respectively, were equal and smaller than AEA(7hr), and AEA(14hr). In GC, AEA(7hr), 20.8%, was higher than AEA(14hr), 16.1% (P<0.05) and AEA(18hr), and AEA(total), 9.2 and 8.0%, respectively, were equal and smaller than AEA(7hr) and AEA(14hr). The serum TP and IGF-I were not affected by colostrum feeding. Considering the variables study in the present work, lyophilized bovine colostrum constitutes a promising alternative substitute to goat colostrum in newborn goat kids, since the supply of immunoglobulins and IGF-I was suitable for the kids. (c) 2012 Elsevier B.V. All rights reserved.
Resumo:
Floating-Harbor syndrome (FHS) is a rare condition characterized by short stature, delayed osseous maturation, expressive-language deficits, and a distinctive facial appearance. Occurrence is generally sporadic, although parent-to-child transmission has been reported on occasion. Employing whole-exome sequencing, we identified heterozygous truncating mutations in SRCAP in five unrelated individuals with sporadic MS. Sanger sequencing identified mutations in SRCAP in eight more affected persons. Mutations were de novo in all six instances in which parental DNA was available. SRCAP is an SNF2-related chromatin-remodeling factor that serves as a coactivator for CREB-binding protein (CREBBP, better known as CBP, the major cause of Rubinstein-Taybi syndrome [RTS]). Five SRCAP mutations, two of which are recurrent, were identified; all are tightly clustered within a small (111 codon) region of the final exon. These mutations are predicted to abolish three C-terminal AT-hook DNA-binding motifs while leaving the CBP-binding and ATPase domains intact. Our findings show that SRCAP mutations are the major cause of FHS and offer an explanation for the clinical overlap between FHS and RTS.
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Cancer-prone genetic disorders are responsible for brain tumors in a considerable proportion of children. Additionally, rare genetic syndromes associated to cancer development may potentially disclose genetic mechanisms related to oncogenesis. We describe two pediatric patients with encephalocraniocutaneous lipomatosis (ECCL), a very rare genetic syndrome with around 60 reported cases, which developed low-grade astrocytoma at 3 and 12 years of age. Patients with ECCL seem to be at risk of benign forms of osseous tumors such as ossifying fibromas, odontomas, and osteomas. The association between brain tumor and ECCL was previously reported only once, in a pediatric case of a mixed neuronal-glial histology. Whether ECCL may be a genetic condition of predisposing brain tumor in children strongly needs to be addressed.
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The aim of this article is to present the pediatric dentistry and orthodontic treatment protocol of rehabilitation of cleft lip and palate patients performed at the Hospital for Rehabilitation of Craniofacial Anomalies - University of So Paulo (HRAC-USP). Pediatric dentistry provides oral health information and should be able to follow the child with cleft lip and palate since the first months of life until establishment of the mixed dentition, craniofacial growth and dentition development. Orthodontic intervention starts in the mixed dentition, at 8-9 years of age, for preparing the maxillary arch for secondary bone graft procedure (SBGP). At this stage, rapid maxillary expansion is performed and a fixed palatal retainer is delivered before SBGP. When the permanent dentition is completed, comprehensive orthodontic treatment is initiated aiming tooth alignment and space closure. Maxillary permanent canines are commonly moved mesially in order to substitute absent maxillary lateral incisors. Patients with complete cleft lip and palate and poor midface growth will require orthognatic surgery for reaching adequate anteroposterior interarch relationship and good facial esthetics.
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Experimental flow boiling heat transfer results are presented for horizontal 1.0 and 2.2 mm I. D. (internal diameter) stainless steel tubes for tests with R1234ze(E), a new refrigerant developed as a substitute for R134a with a much lower global warming potential (GWP). The experiments were performed for these two tube diameters in order to investigate a possible transition between macro and microscale flow boiling behavior. The experimental campaign includes mass velocities ranging from 50 to 1500 kg/m(2) s, heat fluxes from 10 to 300 kW/m(2), exit saturation temperatures of 25, 31 and 35 degrees C, vapor qualities from 0.05 to 0.99 and heated lengths of 180 mm and 361 mm. Flow pattern characterization was performed using high speed videos. Heat transfer coefficient, critical heat flux and flow pattern data were obtained. R1234ze(E) demonstrated similar thermal performance to R134a data when running at similar conditions. [DOI: 10.1115/1.4004933]
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The aim of this study was to investigate the effects of the use of chlorine or ozone as sanitizing agents in the water of chicken immersion chilling, using the residual levels usually applied in Brazil (1.5 ppm), comparing the effects of these treatments on the microbiological, physicochemical, and sensory characteristics of carcasses. Chicken carcasses were chilled in water (4 degrees C) with similar residual levels of ozone and chlorine until reaching temperatures below 7 degrees C (around 45 min). The stability of carcasses was assessed during 15 days of storage at 2 +/- 1 degrees C. Microbiological, surface color (L*, a*, b* parameters), pH value, lipid oxidation (thiobarbituric acid reactive substances index), and sensory evaluation (on a 9-point hedonic scale for odor and appearance) analyses were carried out. The presence of Salmonella was not detected, coagulase-positive staphylococci counts were below 10(2) CFU/ml of rinse fluid, and Escherichia coil and total coliform counts were below 10(5) CFU/ml of rinse fluid until the end of the storage period for both treatments. Psychrotrophic microorganism counts did not differ (P > 0.05) between chlorine and ozone treatments, and both values were near 10(9) CFU/ml of rinse fluid after 15 days at 4 +/- 1 degrees C. pH values did not differ between treatments (P > 0.05) or during the storage period (P > 0.05). In addition, neither chlorine nor ozone treatment showed differences (P > 0.05) in the lipid oxidation of carcasses; however, the thiobarbituric acid reactive substances index of both treatments increased (P <= 0.05) during the storage period, reaching values of approximately 0.68 mg of malonaldehyde per kg. Samples from both treatments did not differ (P > 0.05) in their acceptance scores for odor and overall appearance, but in the evaluation of color, ozone showed an acceptance score significantly higher (P <= 0.05) than that for the chlorine treatment. In general, under the conditions tested, ozone showed results similar to the results for chlorine in the disinfection of chicken carcasses in the immersion chilling, which may indicate its use as a substitute for chlorine in poultry slaughterhouses.