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1.
J Dent Res ; 102(11): 1180-1190, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37555431

ABSTRACT

Despite its reputation as the most widely used restorative dental material currently, resin-based materials have acknowledged shortcomings. As most systematic survival studies of resin composites and dental adhesives indicate, secondary caries is the foremost reason for resin-based restoration failure and life span reduction. In subjects with high caries risk, the microbial community dominated by acidogenic and acid-tolerant bacteria triggers acid-induced deterioration of the bonding interface and/or bulk material and mineral loss around the restorations. In addition, resin-based materials undergo biodegradation in the oral cavity. As a result, the past decades have seen exponential growth in developing restorative dental materials for antimicrobial applications addressing secondary caries prevention and progression. Currently, the main challenge of bioactive resin development is the identification of efficient and safe anticaries agents that are detrimental free to final material properties and show satisfactory long-term performance and favorable clinical translation. This review centers on the continuous efforts to formulate novel bioactive resins employing 1 or multiple agents to enhance the antibiofilm efficacy or achieve multiple functionalities, such as remineralization and antimicrobial activity antidegradation. We present a comprehensive synthesis of the constraints and challenges encountered in the formulation process, the clinical performance-related prerequisites, the materials' intended applicability, and the current advancements in clinical implementation. Moreover, we identify crucial vulnerabilities that arise during the development of dental materials, including particle aggregation, alterations in color, susceptibility to hydrolysis, and loss of physicomechanical core properties of the targeted materials.


Subject(s)
Anti-Infective Agents , Dental Caries , Humans , Dental Restoration, Permanent , Dental Materials , Composite Resins , Dental Caries/prevention & control , Dentistry
2.
Oper Dent ; 46(3): 246-254, 2021 May 01.
Article in English | MEDLINE | ID: mdl-34242393

ABSTRACT

Rehabilitation of an extensively compromised single anterior tooth represents an intriguing challenge for dentists, particularly when the rehabilitation involves esthetic, psychosocial, and functional requirements. The success in rehabilitating a patient with a conservative approach depends on a critical evaluation of the remaining structures, precise treatment plan, systematic treatment strategies, and patient compliance. In this case, the patient's chief complaint was the undesirable appearance of the maxillary right lateral, caused by the displacement of the post and crown. Clinical examination revealed a remaining tooth with coronal fracture, severe loss of tissue due to caries, and absence of ferrule effect. Radiographic examination revealed that the fracture margin was located subgingival. This case report describes a single-tooth rehabilitation involving a combination of root displacement via orthodontic extrusion and crown lengthening. The rehabilitation was followed by post-and-core restoration using a prefabricated glass fiber post associated with a disilicate lithium crown. The clinical decision making and combined effect of both treatment strategies are explained in this report. The treatment required three months, including recovery times after surgery and the placement of the provisional crown. The patient was esthetically and functionally satisfied with the restoration. Patient follow-up examination was performed 24 months after the treatment. This clinical report contributes to the clinical practice and exemplifies the possibility of rehabilitating the natural tooth using combined techniques, which may offer particular advantages regarding prognosis and invested efforts.


Subject(s)
Post and Core Technique , Tooth Fractures , Crown Lengthening , Crowns , Humans , Tooth Crown , Tooth Root
3.
J Dent Res ; 100(10): 1063-1071, 2021 09.
Article in English | MEDLINE | ID: mdl-34167373

ABSTRACT

Cervical composites treating root carious and noncarious cervical lesions usually extend subgingivally. The subgingival margins of composites present poor plaque control, enhanced biofilm accumulation, and cause gingival irritation. A potential material to restore such lesions should combine agents that interfere with bacterial biofilm development and respond to acidic conditions. Here, we explore the use of new bioresponsive bifunctional dental composites against mature microcosm biofilms derived from subgingival plaque samples. The designed formulations contain 2 bioactive agents: dimethylaminohexadecyl methacrylate (DMAHDM) at 3 to 5 wt.% and 20 wt.% nanosized amorphous calcium phosphate (NACP) in a base resin. Composites with no DMAHDM and NACP were used as controls. The newly formulated 5% DMAHDM-20% NACP composite was analyzed by micro-Raman spectroscopy and transmission electron microscopy. The wettability and surface-free energy were also assessed. The inhibitory effect on the in vitro biofilm growth and the 16S rRNA gene sequencing of survival bacterial colonies derived from the composites were analyzed. Whole-biofilm metabolic activity, polysaccharide production, and live/dead images of the biofilm grown over the composites complement the microbiological assays. Overall, the designed formulations had higher contact angles with water and lower surface-free energy compared to the commercial control. The DMAHDM-NACP composites significantly inhibited the growth of total microorganisms, Porphyromonas gingivalis, Prevotella intermedia/nigrescens, Aggregatibacter actinomycetemcomitans, and Fusobacterium nucleatum by 3 to 5-log (P < 0.001). For the colony isolates from control composites, the composition was typically dominated by the genera Veillonella, Fusobacterium, Streptococcus, Eikenella, and Leptotrichia, while Fusobacterium and Veillonella dominated the 5% DMAHDM-20% NACP composites. The DMAHDM-NACP composites contributed to over 80% of reduction in metabolic and polysaccharide activity. The suppression effect on plaque biofilms suggested that DMAHDM-NACP composites might be used as a bioactive material for cervical restorations. These results may propose an exciting path to prevent biofilm growth and improve dental composite restorations' life span.


Subject(s)
Nanocomposites , Aggregatibacter actinomycetemcomitans , Anti-Bacterial Agents , Biofilms , Methacrylates , RNA, Ribosomal, 16S
4.
Eur Arch Paediatr Dent ; 22(2): 157-162, 2021 Apr.
Article in English | MEDLINE | ID: mdl-32424691

ABSTRACT

PURPOSE: Emerging data have suggested that acid erosion has become an increasing clinical problem in pediatric dentistry. This study aimed to investigate the abrasive effects of two commercial toothpastes on primary enamel eroded by orange juice using an in vitro model. METHODS: Thirty enamel slabs were obtained from primary teeth and then randomly assigned to three groups (n = 8) comprising two different toothpastes: G1-control-distilled water; G2-Dentifrice A (containing no fluoride); and G3-Dentifrice B (1.100 ppmF-NaF). Each slab had one half protected to provide a control side, and the other one was subjected to treatments. The slabs were submitted to daily erosive challenges (3×/day, 2 min) in concentrated orange juice (pH 3.38) associated with abrasive challenges using a tooth-brushing machine (150 brush movements for each cycle). During the experimental period, the slabs were kept in 37 °C artificial saliva, and the experiment was carried out for 5 days. The depths of the resulting eroded areas were measured by stylus profilometry. The data were analyzed using ANOVA and the Tukey-Kramer test (α = 5%). RESULTS: Tooth loss (µm, mean ± SD) was 2.46 ± 1.18 for G1, 3.32 ± 2.12 for G2 and 2.14 ± 1.03 for G3. Therefore, the NaF dentifrice (Dentifrice B) produced significantly less mineral loss (p = 0.04) than dentifrice A. CONCLUSIONS: The findings suggest that fluoride toothpaste could protect primary enamel against erosion.


Subject(s)
Tooth Abrasion , Tooth Erosion , Child , Dental Enamel , Fluorides , Humans , Sodium Fluoride , Tooth Abrasion/prevention & control , Tooth Erosion/chemically induced , Tooth Erosion/prevention & control , Toothbrushing , Toothpastes
5.
Arq. bras. med. vet. zootec. (Online) ; 72(5): 1767-1770, Sept.-Oct. 2020. ilus
Article in Portuguese | LILACS, VETINDEX | ID: biblio-1131570

ABSTRACT

Descrevem-se os aspectos clínicos, anatomopatológicos, imuno-histoquímicos, microbiológicos e moleculares de um caso de adenocarcinoma pulmonar associado à infecção por Mycobacterium sp. em uma vaca. O animal apresentou hiporexia, emagrecimento, vocalizações, postura ortopneica, ingurgitamento da jugular, estase venosa positiva, gemido expiratório e morte. Na necropsia, os pulmões estavam aumentados e apresentavam, na superfície pleural, nódulos branco-amarelados, firmes, multifocais a coalescentes, interpostos por áreas avermelhadas. Ao corte, os nódulos aprofundavam-se ao parênquima e possuíam múltiplos focos de aspecto caseoso e friável e áreas de mineralização. O saco pericárdico e os linfonodos traqueobrônquicos, ilíacos, lombares aórticos e mamários apresentavam lesões semelhantes. Histologicamente, observou-se neoformação carcinomatosa associada a áreas multifocais de necrose e mineralização. As células neoplásicas foram fortemente imunomarcadas pelo anticorpo antipancitoqueratina AE1/AE3. Na cultura microbiológica de fragmentos dos pulmões, houve crescimento de colônias bacterianas compatíveis com micobactérias atípicas. O sequenciamento molecular submetido ao BLASTn identificou o Mycobacterium sp. WCM 7299 (ID: gb|KJ873243.1|).(AU)


The clinical, anatomopathological, immunohistochemical, microbiological and molecular aspects of a case of pulmonary adenocarcinoma associated with infection by Mycobacterium sp. in a cow are described. The animal presented hyporexia, weight loss, vocalizations, orthopneic posture, jugular engorgement, positive venous stasis, expiratory groaning and death. At necropsy, the lungs were enlarged and presented firm, multifocal to coalescent yellowish nodules, interposed by reddish areas on the pleural surface. At cut, the nodules deepened to the parenchyma and had multiple foci of caseous and friable appearance and areas of mineralization. The pericardial sac and tracheobronchial, iliac, aortic lumbar and mammary lymph nodes showed similar lesions. Histologically, a carcinomatous neoformation, associated with multifocal areas of necrosis and mineralization, was observed. Neoplastic cells were strongly immunolabelled by anti-PanCytokeratin antibody AE1/AE3. Microbiological culture of lung fragments showed growth of bacterial colonies compatible with atypical mycobacteria. Molecular sequencing submitted to BLASTn identified the Mycobacterium sp. WCM 7299 (ID: gb|KJ873243.1|).(AU)


Subject(s)
Animals , Female , Cattle , Adenocarcinoma of Lung/veterinary , Mycobacterium/isolation & purification , Immunohistochemistry/veterinary , Lung Neoplasms/veterinary
6.
Braz J Med Biol Res ; 52(5): e8026, 2019.
Article in English | MEDLINE | ID: mdl-31038577

ABSTRACT

Carassius auratus is a teleost fish that has been largely used in behavioral studies. However, little is known about potential environmental influences on its performance of learning and memory tasks. Here, we investigated this question in C. auratus, and searched for potential correlation between exercise and visuospatial enrichment with the total number of telencephalic glia and neurons. To that end, males and females were housed for 183 days in either an enriched (EE) or impoverished environment (IE) aquarium. EE contained toys, natural plants, and a 12-hour/day water stream for voluntary exercise, whereas the IE had none of the above. A third plus-maze aquarium was used for spatial and object recognition tests. Different visual clues in 2 of its 4 arms were used to guide fish to reach the criteria to complete the task. The test consisted of 30 sessions and was concluded when each animal performed three consecutive correct choices or seven alternated, each ten trials. Learning rates revealed significant differences between EE and IE fish. The optical fractionator was used to estimate the total number of telencephalic cells that were stained with cresyl violet. On average, the total number of cells in the subjects from EE was higher than those from subjects maintained in IE (P=0.0202). We suggest that environmental enrichment significantly influenced goldfish spatial learning and memory abilities, and this may be associated with an increase in the total number of telencephalic cells.


Subject(s)
Cell Proliferation/physiology , Fishes/physiology , Spatial Learning/physiology , Spatial Memory/physiology , Telencephalon/metabolism , Animals , Behavior, Animal/physiology , Cell Count , Female , Male , Physical Conditioning, Animal
7.
Braz. j. med. biol. res ; 52(5): e8026, 2019. tab, graf
Article in English | LILACS | ID: biblio-1001526

ABSTRACT

Carassius auratus is a teleost fish that has been largely used in behavioral studies. However, little is known about potential environmental influences on its performance of learning and memory tasks. Here, we investigated this question in C. auratus, and searched for potential correlation between exercise and visuospatial enrichment with the total number of telencephalic glia and neurons. To that end, males and females were housed for 183 days in either an enriched (EE) or impoverished environment (IE) aquarium. EE contained toys, natural plants, and a 12-hour/day water stream for voluntary exercise, whereas the IE had none of the above. A third plus-maze aquarium was used for spatial and object recognition tests. Different visual clues in 2 of its 4 arms were used to guide fish to reach the criteria to complete the task. The test consisted of 30 sessions and was concluded when each animal performed three consecutive correct choices or seven alternated, each ten trials. Learning rates revealed significant differences between EE and IE fish. The optical fractionator was used to estimate the total number of telencephalic cells that were stained with cresyl violet. On average, the total number of cells in the subjects from EE was higher than those from subjects maintained in IE (P=0.0202). We suggest that environmental enrichment significantly influenced goldfish spatial learning and memory abilities, and this may be associated with an increase in the total number of telencephalic cells.


Subject(s)
Animals , Male , Female , Telencephalon/metabolism , Cell Proliferation/physiology , Fishes/physiology , Spatial Learning/physiology , Spatial Memory/physiology , Physical Conditioning, Animal , Behavior, Animal/physiology , Cell Count
8.
Braz. j. med. biol. res ; 52(1): e7715, 2019. tab, graf
Article in English | LILACS | ID: biblio-974276

ABSTRACT

Photodynamic therapy, by reducing pain and inflammation and promoting the proliferation of healthy cells, can be used to treat recurrent lesions, such as diabetic foot ulcers. Studies using the photosensitizer phthalocyanine, together with the nanostructured copolymeric matrix of Pluronic® and Carbopol® for the treatment of diabetic foot ulcers and leishmaniosis lesions, are showing promising outcomes. Despite their topical or subcutaneous administration, these molecules are absorbed and their systemic effects are unknown. Therefore, we investigated the effect of the subcutaneous administration of the hydroxy-aluminum phthalocyanine hydrogel without illumination on systemic parameters, markers of liver injury, and liver energy metabolism in type 1 diabetic Swiss mice. Both the hydrogel and the different doses of phthalocyanine changed the levels of injury markers and the liver glucose release, sometimes aggravating the alterations caused by the diabetic condition itself. However, the dose of 2.23 µg/mL caused less marked plasmatic and metabolic changes and did not change glucose tolerance or insulin sensitivity of the diabetic mice. These results are indicative that the use of hydroxy-aluminum phthalocyanine hydrogel for the treatment of cutaneous ulcers in diabetic patients is systemically safe.


Subject(s)
Animals , Male , Rabbits , Diabetes Mellitus, Experimental , Aluminum Hydroxide/pharmacology , Glucose/analysis , Indoles/pharmacology , Liver/drug effects , Liver/metabolism , Insulin Resistance , Biomarkers/analysis , Nanoparticles
9.
Braz J Med Biol Res ; 52(1): e7715, 2018 Dec 03.
Article in English | MEDLINE | ID: mdl-30517288

ABSTRACT

Photodynamic therapy, by reducing pain and inflammation and promoting the proliferation of healthy cells, can be used to treat recurrent lesions, such as diabetic foot ulcers. Studies using the photosensitizer phthalocyanine, together with the nanostructured copolymeric matrix of Pluronic® and Carbopol® for the treatment of diabetic foot ulcers and leishmaniosis lesions, are showing promising outcomes. Despite their topical or subcutaneous administration, these molecules are absorbed and their systemic effects are unknown. Therefore, we investigated the effect of the subcutaneous administration of the hydroxy-aluminum phthalocyanine hydrogel without illumination on systemic parameters, markers of liver injury, and liver energy metabolism in type 1 diabetic Swiss mice. Both the hydrogel and the different doses of phthalocyanine changed the levels of injury markers and the liver glucose release, sometimes aggravating the alterations caused by the diabetic condition itself. However, the dose of 2.23 µg/mL caused less marked plasmatic and metabolic changes and did not change glucose tolerance or insulin sensitivity of the diabetic mice. These results are indicative that the use of hydroxy-aluminum phthalocyanine hydrogel for the treatment of cutaneous ulcers in diabetic patients is systemically safe.


Subject(s)
Aluminum Hydroxide/pharmacology , Diabetes Mellitus, Experimental , Glucose/analysis , Indoles/pharmacology , Liver/drug effects , Liver/metabolism , Nanoparticles , Animals , Biomarkers/analysis , Insulin Resistance , Isoindoles , Male , Mice
10.
J Dent Res ; 96(8): 855-863, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28530844

ABSTRACT

Dental caries is prevalent, and secondary caries causes restoration failures. This article reviews recent studies on developing a new generation of bioactive resins with anticaries properties. Extensive effects were made to develop new antimicrobial composites, bonding agents, and other resins containing quaternary ammonium methacrylates to suppress plaque buildup and bacterial acid production. The effects of alkyl chain length and charge density and the antimicrobial mechanisms for chlorhexidine, nano-silver, quaternary ammonium methacrylates, and protein-repellent agents were discussed. Synergistic effects of contact-killing and protein-repellent properties were shown to yield the greatest biofilm-inhibition effects. The combination of antimicrobial, protein-repellent, and calcium phosphate nanoparticle remineralization was suggested to provide maximal anticaries effects. In addition, for use orally, cytotoxicity and biocompatibility were important considerations for the new bioactive materials. Furthermore, rather than kill all bacteria, it would be more desirable to modulate the oral biofilm compositions via bioactive resins to suppress cariogenic/pathogenic species and promote benign species. For widespread clinical use of the new antimicrobial and therapeutic materials, whether they would induce bacterial drug resistance needs to be determined, which requires further study. Nonetheless, the new generation of bioactive anticaries resins with therapeutic and biofilm acid-inhibiting properties has the potential to substantially benefit oral health.


Subject(s)
Anti-Infective Agents/pharmacology , Cariostatic Agents/pharmacology , Dental Caries/microbiology , Dental Caries/prevention & control , Resins, Synthetic/pharmacology , Biocompatible Materials/pharmacology , Biofilms/drug effects , Calcium Phosphates/pharmacology , Chlorhexidine/pharmacology , Dental Plaque/microbiology , Dental Plaque/prevention & control , Humans , Methacrylates/pharmacology , Nanoparticles , Quaternary Ammonium Compounds/pharmacology
11.
Eur J Gynaecol Oncol ; 37(5): 700-702, 2016.
Article in English | MEDLINE | ID: mdl-29787014

ABSTRACT

OBJECTIVE: To evaluate polymorphism frequency of the CYP2D6*4, *10, and * 17 alleles in women with breast cancer treated with tamoxifen. MATERIALS AND METHODS: Ninety-five women with estrogen and progesterone receptor-positive breast carcinoma were investigated from September to December 2013. A three-ml sample of peripheral blood was collected from each patient to analyze the presence of CYP2D6 *4, *10, and *17 allele polymorphism by specific polymerase chain reaction technique (PCR) for analysis of haplotypes *1, *4, *10, and *17, determined by studies of different single-nucleotide polymorphism (SNP). The data obtained were compiled and analyzed with the aid of Excel software 2010. RESULTS: The frequency of CYP2D6 alleles *4, *10, and *17 was 16%, 29%, and 2%, respectively, and haplotype * 1/*10 was shown in 22% of the women. The phenotype of intermediate metabolism occurred in 8% of women. CONCLUSIONS: The present study showed a deficiency in tamoxifen metabolism, characterized by intermediate metabolism in 8% of Brazilian women.


Subject(s)
Antineoplastic Agents, Hormonal/therapeutic use , Breast Neoplasms/drug therapy , Cytochrome P-450 CYP2D6/genetics , Polymorphism, Single Nucleotide , Tamoxifen/therapeutic use , Breast Neoplasms/genetics , Female , Haplotypes , Humans , Tamoxifen/metabolism
12.
Photodiagnosis Photodyn Ther ; 12(4): 581-6, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26431977

ABSTRACT

BACKGROUND: Ultraconservative removal of carious tissue is becoming increasingly highlighted for management of deep caries lesions, and combined with an antimicrobial photochemistry-based treatment modality (PACT), this approach can be enhanced favoring dental tissue repair and preservation. The aim was to investigate the effectiveness of PACT using a light emitting diode (LED) associated with a photosensitizer toluidine blue ortho (TBO) on deep caries lesions. METHODS: For that, a single blind, randomized, controlled, split-mouth clinical trial where 45 patients with at least two deep carious lesions on permanent posterior teeth was performed. The primary intervention was deep caries lesion management with disinfection of remaining dentin tissue using PACT. Bacterial counts were measured following treatments as the main outcome. The remaining dentinal samples of each lesion were treated with either non-PACT-control or PACT. The PACT procedure were characterized by 100 µg mL(-1) TBO followed by 94J cm(-2) LED irradiation. Samples of dentin were collected before and immediately after treatments for microbiological analysis of total viable bacteria, mutans streptococci and Lactobacillus spp. counts. Microbial reduction was data were submitted to unpaired t test (α=5%). RESULTS: PACT led to statistically significant reductions in mutans streptococci (1.08 ± 1.20 log), Lactobacillus spp. (1.69 ± 1.37 log), and total viable bacteria (1.07 ± 1.01 log) compared to the control, which showed log reductions respectively of 0.05 ± 0.49, 0.52 ± 0.89, and 0.47 ± 0.77 for the same microorganisms. CONCLUSION: Dentin from deep carious lesions treated with PACT showed a decrease in cariogenic microbial load.


Subject(s)
Dental Caries/drug therapy , Photochemotherapy/methods , Photosensitizing Agents/therapeutic use , Tolonium Chloride/therapeutic use , Dental Caries/therapy , Female , Humans , Lactobacillus/drug effects , Male , Single-Blind Method , Streptococcus mutans/drug effects
13.
Environ Sci Pollut Res Int ; 22(23): 18987-93, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26233737

ABSTRACT

Energetic characterization of biomass allows for assessing its energy potential for application in different conversion processes into energy. The objective of this study is to physicochemically characterize pineapple crown leaves (PC) for their application in energy conversion processes. PC was characterized according to ASTM E871-82, E1755-01, and E873-82 for determination of moisture, ash, and volatile matter, respectively; the fixed carbon was calculated by difference. Higher heating value was determined by ASTM E711-87 and ash chemical composition was determined by XRF. The thermogravimetric and FTIR analyses were performed to evaluate the thermal decomposition and identify the main functional groups of biomass. PC has potential for application in thermochemical processes, showing high volatile matter (89.5%), bulk density (420.8 kg/m(3)), and higher heating value (18.9 MJ/kg). The results show its energy potential justifying application of this agricultural waste into energy conversion processes, implementing sustainability in the production, and reducing the environmental liabilities caused by its disposal.


Subject(s)
Ananas/chemistry , Biomass , Renewable Energy , Agriculture , Carbon/analysis , Plant Leaves/chemistry
14.
Minerva Stomatol ; 63(11-12): 421-6, 2014.
Article in English | MEDLINE | ID: mdl-25503343

ABSTRACT

AIM: Diabetes mellitus (DM) is one of the most common chronic diseases responsible for substantial loss on the quality of life in elderly. Oral manifestations in these patients include xerostomia and alterations in salivary flow and salivary pH. The aim of this study was to analyze the relationship between salivary flow, pH and medication. METHODS: The sample consisted of 53 subjects aged 60 years and older, including 30 patients with a diagnosis of type 2 DM and 23 controls. RESULTS: Salivary flow was 1.066±0.814 mL/min in the control group and 0.955±0.606 mL/min in the DM group, with no significant difference between groups (P=0.588). There was a significant difference (P=0.045) in mean salivary pH (DM: 5.267±0.828; control: 5.783±0.951). Only 32.07% of the patients reported to remove their denture while sleeping. Three of 53 subjects using medications presented severe drug interactions. CONCLUSION: In summary, dentists must be able to make the diagnosis, to recognize all factors related to salivary alterations in DM, and to prescribe adequate treatment related to oral condition. Patients with DM presented salivary pH below normal reference values. It is important to advice patients to remove their denture while sleeping in order to prevent traumatic irritations and infections with Candida albicans. Potentially harmful cases of drug interactions have to be observed in elderly patient. Further studies focusing on the nature of drug interactions as the cause of adverse events such as xerostomia and increased salivary pH are needed.


Subject(s)
Diabetes Mellitus/drug therapy , Diabetes Mellitus/physiopathology , Saliva/chemistry , Salivation , Xerostomia/chemically induced , Xerostomia/physiopathology , Drug Interactions , Female , Humans , Hydrogen-Ion Concentration , Male , Middle Aged
15.
Transgenic Res ; 23(6): 1043-7, 2014 Dec.
Article in English | MEDLINE | ID: mdl-24659218

ABSTRACT

The Brazilian National Biosafety Committee approved in 2011 a new post release monitoring system for environmental releases of genetically modified organisms. It has a number of novel features in comparison with other established or proposed systems. The new system also allows the proponent to ask for monitoring exemption. General surveillance forms the basis of the monitoring system, similar to the European model, but differs markedly in the way it operates. While the European proposal is based on monitoring measurable variables extracted from environmental observations, from baselines previously established for multiple protection targets, the Brazilian system uses direct alerts of damage, without the aid of baseline values. The strength of the Brazilian form of monitoring is the possibility of generating an information network with the effective participation of many actors from the monitored area. A network constituted by highly qualified members, as proposed elsewhere, is too complex and unrealistic in Brazil and in many other countries. In conclusion, the Brazilian monitoring system is flexible and can be adjusted to the Brazilian reality over the next years, as a response to the ever growing experience in monitoring. It also meets the demands of the Brazilian society for transparency, rational use of resources, opportunity for national companies, and food and environmental biosafety.


Subject(s)
Environmental Exposure/prevention & control , Environmental Monitoring/methods , Plants, Genetically Modified/adverse effects , Risk Assessment/methods , Brazil , Humans
16.
Parasite Immunol ; 36(7): 313-23, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24606067

ABSTRACT

Serodiagnosis of visceral leishmaniasis is often hindered by cross-reactions to other parasitic diseases. Identifying specific B-cell epitopes in proteins is therefore important for immunodiagnostics, as well as for disease control by vaccines. This study aimed to identify linear and conformational B-cell epitopes and to evaluate the secondary structure of antigen proteins in Leishmania infantum using in silico analysis. Linear epitopes were predicted using the Immune Epitope Database and Analysis Resource (IEDB), BepiPred and BcePred programs. The conformational B-cell epitopes were identified using the CBTOPE server. The combination of the predictions using IEDB, BepiPred and BcePred generated 148 linear epitopes from the calpain-like cysteine peptidase (CP), thiol-dependent reductase 1 (TDR1) and HSP70 proteins. In total, 164 conformational epitopes were predicted, mostly located in the linear epitope region. The predicted epitopes are located in α helix and random coil regions in the thiol-dependent reductase 1 and HSP70 proteins. New linear and conformational B-cell epitopes of L. infantum proteins were identified in silico, and the prediction using various programs ensures greater accuracy of the results, as suggested by confirmation of previously identified HSP70 epitopes.


Subject(s)
Antigens, Protozoan/immunology , Epitopes, B-Lymphocyte/immunology , Leishmania infantum/immunology , Leishmaniasis, Visceral/immunology , Amino Acid Sequence , Antigens, Protozoan/chemistry , Computational Biology/methods , Cysteine Endopeptidases/chemistry , Cysteine Endopeptidases/immunology , HSP70 Heat-Shock Proteins/chemistry , HSP70 Heat-Shock Proteins/immunology , Humans , Leishmaniasis, Visceral/diagnosis , Leishmaniasis, Visceral/parasitology , Molecular Sequence Data , Oxidoreductases/chemistry , Oxidoreductases/immunology
17.
Arq. bras. med. vet. zootec ; 65(5): 1394-1402, out. 2013. graf, tab
Article in English | LILACS | ID: lil-689757

ABSTRACT

This paper aims to evaluate the efficiency of three inactive vaccines against contagious agalactia prepared with samples of Mycoplasma agalactiae isolated in Brazil and different adjuvants. Vaccine 1 adsorbed with aluminum hydroxide was administered in 23 goats (Gc1) and 13 sheep (Gov1); vaccine 2 containing Montanide IMS-2215-VG was administered in 22 goats (Gc2) and 12 sheep (Gov2) and vaccine 3, containing Montanide Gel-01 was administered in 22 goats (Gc3) and 12 sheep (Gov3). All animals were negative for Ma at indirect ELISA and received two doses of 2mL each, subcutaneously, within a 21 day interval. Five animals from each species were used as control. Seventy-five days after the booster, four animals from each vaccinated group and two from the control group were challenged with 5mL of Ma culture containing 10(7)cfu/mL, orally and through immersion of the female's udder in lactation. The serological response was analyzed during vaccination days (0 and 21) and at 51, 81, 111, 141 and 171 days after vaccination. The collection and analysis of the challenged animals were conducted at the day of the challenge (D0) and 7, 14, 21, 28, 35, 42, 49 and 56 days after the challenge. The three vaccines induced the production of antibodies, having no significant statistical difference (p<0.05). Animals from groups Gc1, Gc2 and Gov2 developed higher levels of antibodies, with significant statistical difference compared to the other vaccinated group and control group (p<0.05). After the challenge, the animals from the control presented an increase in regional lymph nodes and conjunctivitis, mastitis and arthritis. In four vaccinated animals, discrete conjunctivitis and congestion of the episcleral veins was observed. It is concluded that vaccines 1 and 2 induced levels of protective antibodies in goats and sheep, sufficient for clinical protection of the animals submitted to the experimental infection, indicating its use on the prevention of contagious agalactia.


Este trabalho tem como objetivo avaliar a eficácia de três vacinas inativadas contra agalaxia contagiosa, preparadas com amostra de Mycoplasma agalactiae isolada no Brasil e diferentes adjuvantes. A vacina 1, adsorvida com hidróxido de alumínio, foi administrada em 23 caprinos (Gc1) e 13 ovinos (Gov1); a vacina 2, contendo Montanide IMS-2215-VG, foi administrada em 22 caprinos (Gc2) e 12 ovinos (Gov2); e a vacina 3, contendo Montanide Gel-01 foi administrada em 22 caprinos (Gc3) e 12 ovinos (Gov3). Todos os animais eram negativos para Ma no ELISA indireto e receberam duas doses de 2mL cada, por via subcutânea, com intervalo de 21 dias. Cinco animais de cada espécie foram utilizados como controle. Setenta e cinco dias após o reforço, quatro animais de cada grupo vacinado e dois do grupo controle foram desafiados com 5mL de cultura de Ma contendo 10(7)ufc/mL, por via oral e pela imersão dos tetos das fêmeas em lactação. A resposta sorológica foi analisada nos dias da vacinação (zero e 21) e aos 51, 81, 111, 141 e 171 dias pós-vacinação. As coletas e análises dos animais desafiados foram realizadas no dia do desafio (D0) e sete, 14, 21, 28, 35, 42, 49 e 56 dias pós-desafio. As três vacinas induziram produção de anticorpos, não havendo diferença estatisticamente significativa entre caprinos e ovinos (P>0,05). Animais dos grupos Gc1, Gc2 e Gov2 produziram níveis de anticorpos mais elevados, com diferença estatisticamente significativa em relação aos demais grupos vacinados e ao grupo controle (P<0,05). Após o desafio, os animais do grupo controle apresentaram aumento de linfonodos regionais e conjuntivite, mastite e artrite. Em quatro animais vacinados, foi observada discreta conjuntivite e congestão dos vasos episclerais. Conclui-se que as vacinas 1 e 2 induziram níveis de anticorpos protetores em caprinos e ovinos suficientes para proteção clínica dos animais submetidos à infecção experimental, podendo ser indicadas para prevenção da agalaxia contagiosa.


Subject(s)
Animals , Mycoplasma agalactiae , Mycoplasma agalactiae/chemistry , Vaccines/administration & dosage , Vaccines/analysis , Vaccines/adverse effects , Enzyme-Linked Immunosorbent Assay/adverse effects , Enzyme-Linked Immunosorbent Assay/veterinary
18.
Arq. bras. med. vet. zootec ; 65(2): 421-429, abr. 2013. ilus, graf, tab
Article in Portuguese | LILACS | ID: lil-673117

ABSTRACT

Determinou-se a dose inseminante para fertilização artificial e descreveu-se o desenvolvimento embrionário de tambaqui (Colossoma macropomum). Os gametas foram coletados de reprodutores induzidos hormonalmente. Foi realizada fertilização artificial nas proporções de espermatozoides/ovócito de D1-50.666; D2-75.999; D3-101.332; D4-126.665; D5-151.998. O desenvolvimento embrionário foi acompanhado por meio de observações periódicas em estereoscópio até a eclosão dos ovos. Na fase de fechamento do blastóporo foi calculada a taxa de fertilização nas diferentes doses inseminantes. A porcentagem de fertilização aumentou de forma linear segundo a equação Ŷ =0,050 + 0,00000773X (R²=97,5), atingindo um platô em 84% na proporção de 102.486 espermatozoides/ovócito. Os embriões apresentaram segmentação meroblástica discoidal, típica de ovos telolécitos, com eclosão ocorrendo aos 357 horas-grau após a fertilização. Conclui-se que o desenvolvimento embrionário de tambaqui obedece ao esperado para peixes com ovos telolécitos e recomenda-se o uso da dose inseminante de aproximadamente 100.000 espermatozoides/ovócito na rotina de fertilização artificial dessa espécie.


The objective of this research was to determine the insemination dose for artificial fertilization and describe the embryonic development of tambaqui (Colossoma macropomun). The gametes were collected from induced breeding hormonally. An artificial fertilization was performed with different sperm/oocyte ratios of D1-50666, D2-75999, D3-101 332, 126 665-D4, D5-151 998 sperm/oocyte. Embryonic development was monitored through periodic stereoscopic observations until hatching. When embryos reached the blastopore closure stage, the rate of fertilization in different insemination doses was calculated. A regression equation was estimated to determine the ideal proportion of the gametes. The fertilization rate increased linearly according to the equation Ŷ = 0.050 + 0.00000773 X (R² = 97.5), up to the proportion of 102.486 spermatozoa/oocyte, and, from this point, the fertilization rate was maintained at 84%. The embryonic development of tambaqui was meroblastic discoidal, as expected from telolecithal eggs and we recommend the use of the insemination dose of approximately 100.000 sperm/oocyte in the artificial fertilization of tambaqui.


Subject(s)
Animals , Embryonic Development/physiology , Spermatozoa/cytology , Insemination/physiology , Reproduction
19.
J Dent Res ; 91(6): 598-604, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22492276

ABSTRACT

Antibacterial bonding agents could combat recurrent caries at the tooth-composite margins. The objectives of this study were to develop novel antibacterial dentin primers containing quaternary ammonium dimethacrylate (QADM) and nanoparticles of silver (NAg), and to investigate the effects on dentin bond strength and dental plaque microcosm biofilms for the first time. Scotchbond Multi-Purpose ("SBMP") bonding agent was used. QADM and NAg were incorporated into SBMP primer, yielding 4 primers: SBMP primer (control), control + 10% QADM (mass), control + 0.05% NAg, and control + 10% QADM + 0.05% NAg. Human saliva was collected to grow microcosm biofilms. The NAg particle size (mean ± SD; n = 100) was 2.7 ± 0.6 nm. Dentin shear bond strengths (n = 10) with human third molars were approximately 30 MPa for all groups (p > 0.1). QADM-NAg-containing primer increased the bacteria inhibition zone by 9-fold, compared with control primer (p < 0.05). QADM-NAg-containing primer reduced lactic acid production and colony-forming units of total micro-organisms, total streptococci, and mutans streptococci by an order of magnitude. In conclusion, novel QADM-NAg-containing primers were strongly antibacterial without compromising dentin bond strength, and hence are promising to inhibit biofilms and secondary caries. The processing method of incorporating QADM and NAg together into the same primer produced the strongest antibacterial effect, which could have a wide applicability to other bonding systems.


Subject(s)
Biofilms/drug effects , Composite Resins/chemistry , Dental Bonding , Dentin-Bonding Agents/chemistry , Resin Cements , Analysis of Variance , Colony Count, Microbial , Dental Restoration, Permanent/methods , Dental Stress Analysis , Humans , Materials Testing , Molar, Third , Nanocomposites/chemistry , Quaternary Ammonium Compounds , Shear Strength , Silver , Statistics, Nonparametric , Streptococcus mutans/drug effects
20.
Reprod Domest Anim ; 46(4): 742-5, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21736637

ABSTRACT

In this study, we analysed the effect on morphology and viability of ovine primordial follicles, when ascorbic acid (AA) was added to vitrification and in vitro culture (IVC) media. For morphological analysis, ovarian tissue was vitrified using DMSO or ethylene glycol (EG), to which AA was added or omitted. After warming, the tissue was fixed for histology or 1-day cultured in the presence or absence of AA. Isolated primordial follicles from ovine ovarian tissue vitrified with DMSO or EG, both supplemented with AA were stained with trypan blue for viability analysis, or 5-day cultured with or without AA followed by a viability analysis. In this study, we report on the successful vitrification protocol developed for ovine ovarian tissue using EG. Vitrification using DMSO reduced the percentage of morphological normal primordial follicles, whereas addition of AA to the vitrification and culture media did enhance these results (p < 0.05). However, vitrification in a DMSO + AA medium followed by 5-day IVC resulted in a significant decrease in the follicular viability, independently of the presence of AA in the IVC medium.


Subject(s)
Ascorbic Acid/pharmacology , Culture Media/chemistry , Ovarian Follicle/drug effects , Sheep , Vitrification/drug effects , Animals , Ascorbic Acid/chemistry , Cryoprotective Agents/chemistry , Cryoprotective Agents/pharmacology , Female , Tissue Culture Techniques
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