Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 26
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
Food Microbiol ; 119: 104448, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38225050

RESUMO

We aimed to evaluate the bacterial growth and diversity in vacuum-packed beef bags stored at different temperatures and to monitor blown-pack spoilage. We used culture-based methods and high-throughput sequencing to study the development of the main bacterial groups naturally present in beef stored at 4 and 15 °C for 28 days. The growth of sulfite-reducing clostridium (SRC) was impaired in beef bags stored at 4 °C; significant differences among SRC counts were observed in beef bags stored at 4 and 15 °C on days 14, 21, and 28 (P = 0.001). Blown pack was observed in most beef bags stored at 15 °C, from day 14 to day 28, but not in beef bags stored at 4 °C. A storage temperature of 4 °C was able to maintain a stable bacterial microbiota (most prevalent: Photobacterium, Hafnia-Obesumbacterium, and Lactococcus). Remarkable changes in microbial abundance occurred at 15 °C from day 14 to day 28, with a predominance of strict anaerobes (Bacteroides) and the presence of Clostridium spp. The relative frequencies of strict anaerobes and Clostridium were statistically higher in the beef bags stored at 15 °C (P < 0.001 and P = 0.004, respectively). The temperature influenced the microbial counts and relative abundance of spoilage bacteria, leading to blown pack spoilage.


Assuntos
Embalagem de Alimentos , Microbiota , Animais , Bovinos , Embalagem de Alimentos/métodos , Carne/microbiologia , Temperatura , Vácuo , Bactérias/genética , Clostridium , Microbiologia de Alimentos
2.
Food Res Int ; 152: 110917, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35181088

RESUMO

Previous work found a high similarity of macro-restriction patterns for isolates of Yersinia enterocolitica 4/O:3 obtained at a pork production chain from Minas Gerais, Brazil. Herein we aimed to determine the clonality and the antibiotic resistance profiles of a subset of these isolates (n = 23) and human clinical isolates (n = 3). Analysis based on whole genome sequencing (WGS) showed that the isolates were distributed into two major clades based on single nucleotide polymorphisms (SNP) with one isolate defining Clade A (isolate R31) and remaining isolates (n = 25, 96.2%) defining Clade B. Seven clonal groups were identified. The inclusion of isolate R31 as a distinct clonal group was due to the presence of several phage-related genes, allowing its characterization as serotype O:5 by WGS. Disk-diffusion assays (14 antibiotics) identified 13 multidrug resistant isolates (50.0%). Subsequent sequence analysis identified 17 different antibiotic resistance related genes. All isolates harbored blaA (y56 beta-lactamase), vatF, rosA, rosB and crp, while nine isolates harbored a high diversity of antibiotic resistance related genes (n = 13). The close genetic relationship among Y. enterocolitica obtained from a pork production chain and human clinical isolates in Brazil was confirmed, and we can highlight the role of swine in the potential transmission of an antibiotic-resistant clones of a pathogenic bio-serotype to humans, or the transmission of these resistant bacteria from people to animals. The role of veterinary antibiotic use in this process is unclear.


Assuntos
Carne de Porco , Carne Vermelha , Yersiniose , Yersinia enterocolitica , Animais , Brasil , Resistência Microbiana a Medicamentos , Genômica , Humanos , Suínos , Yersiniose/microbiologia , Yersiniose/veterinária , Yersinia enterocolitica/genética
3.
Braz J Microbiol ; 51(3): 1177-1190, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32394239

RESUMO

Anaerobic digestion (AD) is a process resulting from the anaerobic metabolism of specific microorganisms that produce an eco-friendly type of energy and a stabilized soil fertilizer. We described the microbial communities and their changes in three depths of BioKöhler® biodigester, fed with cattle manure for 18 days, under anaerobic incubation at the psychrophilic temperature range (~ 20 °C). During the experiment, the maximum methane content in the raw biogas was 79.9%. Non-metric multidimensional scaling (MDS) showed significant differences among microbial communities in the bottom, medium, and upper depths. Considering all the periods of incubation, the microbial communities changed until the eighth day, and they remained stable from eighth to seventeenth days. Bacteroidetes, Firmicutes, and Synergistetes were the most abundant phyla in samples, representing approximately 41% of the total OTUs. The relative abundance of the phyla Euryarchaeota, Actinobacteria, Firmicutes, and Verrucomicrobia changed from bottom to medium sampling points. Moreover, Crenarchaeota differed in frequencies from medium to upper, and Acidobacteria from bottom to upper samples. Lentisphaerae, Chloroflexi, and LD1 were different solely at the bottom, whereas OP9 and Tenericutes only in the medium. Psychrophilic AD performed in this work removed pathogens like Salmonella and Escherichia, as observed at the digestate analyzed. This type of treatment of raw manure besides producing eco-friendly energy efficiently also generates a stabilized and safe biomass that can be used as fertilizer in soils.


Assuntos
Bactérias/metabolismo , Reatores Biológicos/microbiologia , Microbiota , Anaerobiose , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Biocombustíveis/análise , Bovinos , Esterco/análise , Esterco/microbiologia , Metano/metabolismo , Microbiologia do Solo , Fatores de Tempo
4.
Ecotoxicology ; 28(8): 973-982, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31420785

RESUMO

The diamondback moth Plutella xylostella (Linnaeus, 1758) (Lepidoptera: Plutellidae) is a destructive pest of brassica crops of economic importance that have resistance to a range of insecticides. Indole derivates can exert diverse biological activities, and different effects may be obtained from small differences in their molecular structures. Indole is the parent substance of a large number of synthetic and natural compounds, such as plant and animal hormones. In the present study, we evaluate the insecticidal activity of 20 new synthesized indole derivatives against P. xylostella, and the selectivity of these derivatives against non-target hymenopteran beneficial arthropods: the pollinator Apis mellifera (Linnaeus, 1758) (Hymenoptera: Apidae), and the predators Polybia scutellaris (White, 1841), Polybia sericea (Olivier, 1791) and Polybia rejecta (Fabricius, 1798) (Hymenoptera: Vespidae). Bioassays were performed in the laboratory to determine the lethal and sublethal effects of the compounds on P. xylostella and to examine their selectivity to non-target organisms by topical application and foliar contact. The treatments consisted of two synthesized derivatives (most and least toxic), the positive control (deltamethrin) and the negative control (solvent). The synthesized compound 4e [1-(1H-indol-3-yl)hexan-1-one] showed high toxicity (via topical application and ingestion) and decreased the leaf consumption by P. xylostella, displaying a higher efficiency than the pyrethroid deltamethrin, widely used to control this pest. In addition, the synthesized indole derivatives were selective to the pollinator A. mellifera and the predators P. scutellaris, P. sericea and P. rejecta, none of which were affected by deltamethrin. Our results highlight the promising potential of the synthesized indole derivatives for the generation of new chemical compounds for P. xylostella management.


Assuntos
Abelhas/efeitos dos fármacos , Indóis/toxicidade , Inseticidas/toxicidade , Mariposas/efeitos dos fármacos , Vespas/efeitos dos fármacos , Animais , Indóis/farmacologia , Inseticidas/farmacologia , Larva/efeitos dos fármacos
5.
Front Microbiol ; 10: 497, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30967845

RESUMO

Arenization occurs in regions that present sandy soils with normal rainfall levels. Predatory use of environmental sources, the dissolution of arenitic rocks and reworking of non-consolidated surface sands intensify this degradation scenario. Thus, this work aimed to evaluate the impact of the arenization process in the Brazilian Pampa Biome and how this phenomenon affects the soil microbial and plant communities. For this purpose, three arenized areas in Southern Brazil (Pampa Biome) were selected and, in each one, three sampling points were studied: arenized (ARA), arenized to grassland transition (AGT), and grassland (GRA) areas. In the three sampling points, soils presented low levels of nutrients, organic matter, mud and pH acidic in all regions but, the presence of vegetation coverage in AGT and GRA areas preserved the topsoil structure. Our study related ARA with bacterial families Alcaligenaceae, Pseudomonadaceae, and Xanthomonadaceae. AGT with bacterial families Bacillaceae and Burkholderiaceae, and plant species Melinis repens (Willd.) Zizka and Paspalum stellatum Humb. and Bonpl. ex Flüggé, and GRA with bacterial families Koribacteraceae, Hyphomicrobiaceae, and Chthoniobacteraceae, and plant species Croton subpannosus Müll.Arg. ex Griseb., Piptochaetium montevidense (Spreng.) Parodi and Elyonurus sp. The three studied areas (as well as sampling points) present soils extremely poor in nutrients with sandy texture, and the bacterial and plant composition well known to be resistant to environmental stresses were dominant. The vulnerability of these areas causes a degradation scenario, which is worsened by agricultural activities. However, in general, this phenomenon is a natural process that occurs mainly due to soil characteristics (poor soils) and climatic variations.

6.
Antonie Van Leeuwenhoek ; 111(4): 533-550, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29110156

RESUMO

As the depth increases and the light fades in oceanic cold seeps, a variety of chemosynthetic-based benthic communities arise. Previous assessments reported polychaete annelids belonging to the family Siboglinidae as part of the fauna at cold seeps, with the 'Vestimentifera' clade containing specialists that depend on microbial chemosynthetic endosymbionts for nutrition. Little information exists concerning the microbiota of the external portion of the vestimentiferan trunk wall. We employed 16S rDNA-based metabarcoding to describe the external microbiota of the chitin tubes from the vestimentiferan Escarpia collected from a chemosynthetic community in a cold seep area at the southwestern Atlantic Ocean. The most abundant operational taxonomic unit (OTU) belonged to the family Pirellulaceae (phylum Planctomycetes), and the second most abundant OTU belonged to the order Methylococcales (phylum Proteobacteria), composing an average of 21.1 and 15.4% of the total reads on tubes, respectively. These frequencies contrasted with those from the surrounding environment (sediment and water), where they represent no more than 0.1% of the total reads each. Moreover, some taxa with lower abundances were detected only in Escarpia tube walls. These data constitute on the first report of an epibiont microbial community found in close association with external surface of a cold-seep metazoan, Escarpia sp., from a chemosynthetic community in the southwestern Atlantic Ocean.


Assuntos
Bactérias/classificação , Biodiversidade , Sedimentos Geológicos/microbiologia , Microbiota/fisiologia , Poliquetos/microbiologia , Água do Mar/microbiologia , Animais , Oceano Atlântico , Crescimento Quimioautotrófico , Código de Barras de DNA Taxonômico , Ecossistema , Metagenoma/genética , Planctomycetales , Poliquetos/ultraestrutura , RNA Ribossômico 16S/genética
7.
Appl Microbiol Biotechnol ; 100(2): 719-28, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26454865

RESUMO

To reduce dependence on petroleum, an alternative route to production of the chemical feedstock 2,3-butanediol (2,3-BD) from renewable lignocellulosic sources is desirable. In this communication, the genes encoding the pathway from pyruvate to 2,3-BD (alsS, alsD, and bdhA encoding acetolactate synthase, acetolactate decarboxylase, and butanediol dehydrogenase, respectively) from Bacillus subtilis were engineered into a single tricistronic operon under control of the isopropyl ß-D-1-thiogalactopyranoside (IPTG)-inducible Pspac promoter in a shuttle plasmid capable of replication and expression in either B. subtilis or Escherichia coli. We describe the construction and performance of a shuttle plasmid carrying the IPTG-inducible synthetic operon alsSDbdhA coding for 2,3-BD pathway capable of (i) expression in two important representative model microorganisms, the gram-positive B. subtilis and the gram-negative E. coli; (ii) increasing 2,3-BD production in B. subtilis; and (iii) successfully introducing the B. subtilis 2,3-BD pathway into E. coli. The synthetic alsSDbdhA operon constructed using B. subtilis native genes not only increased the 2,3-BD production in its native host but also efficiently expressed the pathway in the heterologous organism E. coli. Construction of an efficient shuttle plasmid will allow investigation of 2,3-BD production performance in related organisms with industrial potential for production of bio-based chemicals.


Assuntos
Bacillus subtilis/genética , Butileno Glicóis/metabolismo , Escherichia coli/genética , Microbiologia Industrial/métodos , Óperon , Acetolactato Sintase/genética , Acetolactato Sintase/metabolismo , Oxirredutases do Álcool/genética , Oxirredutases do Álcool/metabolismo , Bacillus subtilis/metabolismo , Carboxiliases/genética , Carboxiliases/metabolismo , Escherichia coli/metabolismo , Fermentação , Plasmídeos , Regiões Promotoras Genéticas , Biologia Sintética
8.
Int J Syst Evol Microbiol ; 65(Pt 2): 556-561, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25392348

RESUMO

A novel, psychrotolerant facultative anaerobe, strain WN1359(T), was isolated from a permafrost borehole sample collected at the right bank of the Kolyma River in Siberia, Russia. Gram-positive-staining, non-motile, rod-shaped cells were observed with sizes of 1-2 µm long and 0.4-0.5 µm wide. Growth occurred in the range of pH 5.8-9.0 with optimal growth at pH 7.8-8.6 (pH optimum 8.2). The novel isolate grew at temperatures from 0-37 °C and optimal growth occurred at 25 °C. The novel isolate does not require NaCl; growth was observed between 0 and 8.8 % (1.5 M) NaCl with optimal growth at 0.5 % (w/v) NaCl. The isolate was a catalase-negative, facultatively anaerobic chemo-organoheterotroph that used sugars but not several single amino acids or dipeptides as substrates. The major metabolic end-product was lactic acid in the ratio of 86 % l-lactate : 14 % d-lactate. Strain WN1359(T) was sensitive to ampicillin, chloramphenicol, fusidic acid, lincomycin, monocycline, rifampicin, rifamycin SV, spectinomycin, streptomycin, troleandomycin and vancomycin, and resistant to nalidixic acid and aztreonam. The fatty acid content was predominantly unsaturated (70.2 %), branched-chain unsaturated (11.7 %) and saturated (12.5 %). The DNA G+C content was 35.3 mol% by whole genome sequence analysis. 16S rRNA gene sequence analysis showed 98.7 % sequence identity between strain WN1359(T) and Carnobacterium inhibens. Genome relatedness was computed using both Genome-to-Genome Distance Analysis (GGDA) and Average Nucleotide Identity (ANI), which both strongly supported strain WN1359(T) belonging to the species C. inhibens. On the basis of these results, the permafrost isolate WN1359(T) represents a novel subspecies of C. inhibens, for which the name Carnobacterium inhibens subsp. gilichinskyi subsp. nov. is proposed. The type strain is WN1359(T) ( = ATCC BAA-2557(T) = DSM 27470(T)). The subspecies Carnobacterium inhibens subsp. inhibens subsp. nov. is created automatically. An emended description of C. inhibens is also provided.


Assuntos
Carnobacterium/classificação , Pergelissolo/microbiologia , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Dados de Sequência Molecular , RNA Ribossômico 16S/genética , Federação Russa , Análise de Sequência de DNA
9.
Med Chem ; 10(6): 580-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24295020

RESUMO

Special attention has been given to the mosquito Aedes aegypti Linn. (Diptera: Culicidae) owing to numerous dengue epidemic outbreaks worldwide. Failure to control vector spreading is accounted for unorganized urban growth and resistance to larvicides and insecticides. Therefore, researchers are currently searching for new and more efficient larvicides and insecticides to aid dengue control measures. Triptamine is known to affect insect behavior, development, and physiology. Expression of this compound in plants has reduced the growth rate of herbivore insects. In view of these facts, it was of our interest to synthesize triptamine amide derivatives as potential larvicides against Ae. aegypti, establishing a Structure-Activity Relationship. Eleven amide derivatives of triptamine were synthesized, characterized, and evaluated for their larvicidal activity against third-instar Ae. aegypti larvae. N-(2-(1H-indol-3-yl)ethyl)-2,2,2-trichloroacetamide exhibited the highest overall larvicidal potency, while N-(2-(1H-Indol-3-yl)ethyl) acetamide displayed the lowest larvicidal potency. A regression equation correlating the larvicidal activity with Log P was obtained. We have found a clear relationship between the larvicidal activity of non-chlorinated compounds and Log P. Analysis of the relationship between Log P and larvicidal activity against Ae. aegypti may be useful in the evaluation of potential larvicidal compounds.


Assuntos
Aedes/efeitos dos fármacos , Inseticidas/química , Inseticidas/síntese química , Triptaminas/química , Triptaminas/síntese química , Aedes/crescimento & desenvolvimento , Animais , Dengue/prevenção & controle , Inseticidas/farmacologia , Larva , Dose Letal Mediana , Estrutura Molecular , Relação Quantitativa Estrutura-Atividade , Triptaminas/farmacologia
10.
Braz Dent J ; 24(4): 402-9, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24173265

RESUMO

In a previous study in dogs, the early removal of expanded polytetrafluoroethylene (ePTFE) membrane (2 weeks after placement) showed histomorphometric results (of new bone, cementum and periodontal ligament) similar to that obtained with membrane removal at 4 weeks after placement. This study evaluated the influence of early removal of an ePTFE membrane on the treatment of Class II furcation defects. Twelve patients who provided 12 pairs of mandibular furcation defects were recruited for the study. Baseline clinical measurements were recorded: plaque index (PI), gingival index (GI), bleeding on probing (BOP), probing depth (PD), gingival margin position (GMP) and relative clinical attachment level (RCAL). Full flaps were elevated and hard tissue measurements were performed during the surgery: relative vertical (RVBL) and horizontal (RHBL) bone level. The ePTFE membranes were adapted and sutured to their correspondent tooth and removed at 2 weeks in the test group (TGr) and at 4 weeks in the control group (CGr). After 1 year all sites were re-entered, and soft and hard tissue measurements were recorded. There were no statistically significant differences between TGr and CGr for any baseline measurement. After 12 months, there were no statistically significant differences between TGr and CGr in the PD (p=0.74), GMP (p=0.76) and RCAL (p=0.44) values. However, the RHBL resolution was significant for both groups (CGr p=0.01 and TGr p=0.02), without difference between groups (p=0.39). Early removal of membranes did not affect the outcome on the treatment of Class II furcation defects.


Assuntos
Má Oclusão Classe II de Angle/cirurgia , Politetrafluoretileno , Humanos , Índice Periodontal
11.
Braz. dent. j ; 24(4): 402-409, July-Aug/2013. tab, graf
Artigo em Inglês | LILACS | ID: lil-689838

RESUMO

In a previous study in dogs, the early removal of expanded polytetrafluoroethylene (ePTFE) membrane (2 weeks after placement) showed histomorphometric results (of new bone, cementum and periodontal ligament) similar to that obtained with membrane removal at 4 weeks after placement. This study evaluated the influence of early removal of an ePTFE membrane on the treatment of Class II furcation defects. Twelve patients who provided 12 pairs of mandibular furcation defects were recruited for the study. Baseline clinical measurements were recorded: plaque index (PI), gingival index (GI), bleeding on probing (BOP), probing depth (PD), gingival margin position (GMP) and relative clinical attachment level (RCAL). Full flaps were elevated and hard tissue measurements were performed during the surgery: relative vertical (RVBL) and horizontal (RHBL) bone level. The ePTFE membranes were adapted and sutured to their correspondent tooth and removed at 2 weeks in the test group (TGr) and at 4 weeks in the control group (CGr). After 1 year all sites were re-entered, and soft and hard tissue measurements were recorded. There were no statistically significant differences between TGr and CGr for any baseline measurement. After 12 months, there were no statistically significant differences between TGr and CGr in the PD (p=0.74), GMP (p=0.76) and RCAL (p=0.44) values. However, the RHBL resolution was significant for both groups (CGr p=0.01 and TGr p=0.02), without difference between groups (p=0.39). Early removal of membranes did not affect the outcome on the treatment of Class II furcation defects.


Em estudo prévio, em cães, a remoção precoce da membrana de politetrafluoretileno expandido (PTFE-e), 2 semanas após a colocação, mostrou resultados histomorfométricos (formação de novo osso, cemento e ligamento periodontal) similares aos de remoção da membrana 4 semanas após a sua colocação. Este estudo avaliou a influência da remoção precoce de uma membrana de PTFE-e no tratamento de defeitos de bifurcação classe II. Foram selecionados para o estudo 12 pacientes, com 12 pares de defeitos de bifurcação mandibulares. Foram feitas as seguintes medidas clínicas iniciais: índice de placa (IP), índice gingival (IG), sangramento à sondagem (SAS), profundidade de sondagem (PS), posição da margem gingival (PMG) e nível relativo da inserção clínica (NRIC). Foram elevados retalhos totais e as medidas do tecido ósseo foram tomadas transcirurgicamente: níveis ósseos vertical (NOV) e horizontal (NOH). Membranas de PTFE-e foram adaptadas e suturadas aos dentes correspondentes e removidas após 2 semanas no grupos teste (GT) ou quatro semanas no grupo controle (GC). Após 1 ano, em todos os sites foi realizada reentrada cirúrgica e medidas clínicas e ósseas foram novamente feitas. Não houve diferenças estatisticamente significantes entre GT e GC para nenhuma das medidas iniciais avaliadas. Após 12 meses, não houve diferenças estatisticamente significantes entre GT e GC para os valores de PS (p=0,74), PMG (p=0,76) e NRIC (p=0,44). Entretanto, a resolução do nível ósseo horizontal foi significante para ambos os grupos (GC: p=0,01 e GT: p=0,02), sem diferenças entre grupos (p=0,39). A remoção precoce da membrana não afetou os resultados do tratamento de defeitos de bifurcação Classe II.


Assuntos
Humanos , Má Oclusão Classe II de Angle/cirurgia , Politetrafluoretileno , Índice Periodontal
12.
Appl Microbiol Biotechnol ; 97(16): 7307-16, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23576037

RESUMO

Bacillus subtilis ferments pyruvate to 2,3-butanediol via α-acetolactate synthase, α-acetolactate decarboxylase, and butanediol dehydrogenase (BDH), encoded by the alsSD operon and the unlinked monocistronic bdhA gene, respectively. Upstream and divergent from alsSD is the alsR gene that encodes AlsR, a member of the LysR-type transcriptional regulator family. AlsR directly stimulates alsSD transcription by binding to characteristic sites preceding the alsS promoter, but its effect on bdhA expression was unknown. The effect of AlsR on bdhA expression was assessed in a wild-type strain and a congenic strain carrying an alsR::spc knockout mutation by measuring: (a) expression of a transcriptional bdhA-lacZ fusion; (b) bdhA mRNA steady-state levels by quantitative reverse transcriptase PCR; and (c) expression of BDH enzymatic activity. Activation of bdhA expression occurred in early stationary phase, and expression was lowered, but not abolished, in the alsR::spc mutant. Mapping the transcriptional start site of bdhA by primer extension revealed a 268-nucleotide 5'-untranslated region preceding the bdhA initiation methionine codon. Transcription initiation was not reduced in the alsR::spc mutant, and by electrophoretic mobility shift assay, purified AlsR protein did not bind to the bdhA promoter region, suggesting that bdhA expression is indirectly under AlsR transcriptional control.


Assuntos
Oxirredutases do Álcool/biossíntese , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Butileno Glicóis/metabolismo , Regulação Bacteriana da Expressão Gênica , Fatores de Transcrição/metabolismo , Regiões 5' não Traduzidas , Oxirredutases do Álcool/genética , Fusão Gênica Artificial , Códon de Iniciação , Perfilação da Expressão Gênica , Técnicas de Inativação de Genes , Genes Reporter , Ácido Pirúvico/metabolismo , Fatores de Transcrição/genética , Sítio de Iniciação de Transcrição , Transcrição Gênica , beta-Galactosidase/genética , beta-Galactosidase/metabolismo
13.
J Clin Periodontol ; 39(11): 1089-96, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22966787

RESUMO

AIM: To characterize anatomical features of altered passive eruption (APE)-affected teeth using cone beam computed tomography (CBCT) and to present a novel combined surgical approach to its correction. CLINICAL INNOVATION REPORT: Eighty-four teeth from 14 subjects affected by APE were subjected to CBCT. Periodontal variables were recorded before surgery, and anatomical variables were measured on CBCTs. Clinical crown length was measured on study casts. Surgical treatment was carried out based on the lengths of the anatomical crowns transferred to a surgical guide that served as a reference for the incisions. The mean distance between the CEJ and the bone crest was on average <1 mm, facial bone thickness was ≥ 1 mm and soft tissue thickness was >1 mm for every tooth analysed; no association between the soft and the hard tissue thicknesses was observed. CONCLUSION: The CBCT can be used in the diagnosis and treatment planning of APE cases. Anatomically, the APE cases described often presented a thick facial bone plate.


Assuntos
Gengiva/anatomia & histologia , Gengivoplastia/métodos , Odontometria/instrumentação , Coroa do Dente/anatomia & histologia , Erupção Dentária , Adulto , Tomografia Computadorizada de Feixe Cônico , Arco Dental/diagnóstico por imagem , Estética Dentária , Feminino , Gengiva/diagnóstico por imagem , Humanos , Masculino , Modelos Dentários , Planejamento de Assistência ao Paciente , Coroa do Dente/diagnóstico por imagem
14.
J Endod ; 38(3): 360-6, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22341075

RESUMO

INTRODUCTION: This study evaluated the in vivo response of apical and periapical tissues of dogs' teeth with apical periodontitis after one-session endodontic treatment with and without antimicrobial photodynamic therapy (aPDT). METHODS: Sixty root canals with experimentally induced apical periodontitis were instrumented and assigned to 4 groups receiving aPDT and root canal filling (RCF) or not: group aPDT+/RCF+ (n = 20): aPDT (photosensitizer phenothiazine chloride at 10 mg/mL for 3 minutes and diode laser [λ = 660 nm, 60 mW/cm(2)] for 1 minute) and RCF in the same session; group aPDT+/RCF- (n = 10); group aPDT-/RCF+ (n = 20), and group aPDT-/RCF- (n = 10). Teeth were restored, and the animals were killed after 90 days. Sections from the maxillas and mandibles were stained with hematoxylin-eosin and Mallory trichrome and examined under light microscopy. Descriptive (ie, newly formed apical mineralized tissue, periapical inflammatory infiltrate, apical periodontal ligament thickness, and mineralized tissue resorption) and quantitative (ie, periapical lesion size and number of inflammatory cells) microscopic analysis was performed. Quantitative data were analyzed by the Kruskal-Wallis and Dunn tests (α = .05). RESULTS: In the aPDT-treated groups, the periapical region was moderately/severely enlarged with no inflammatory cells, moderate neoangiogenesis and fibrogenesis, and the smallest periapical lesions. CONCLUSIONS: Although apical closure by mineralized tissue deposition was not achieved, the absence of inflammatory cells, moderate neoangiogenesis, and fibrogenesis in the periapical region in the groups treated with aPDT indicate that this can be a promising adjunct therapy to cleaning and shaping procedures in teeth with apical periodontitis undergoing one-session endodontic treatment.


Assuntos
Anti-Infecciosos/uso terapêutico , Periodontite Periapical/tratamento farmacológico , Fenotiazinas/uso terapêutico , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/uso terapêutico , Tratamento do Canal Radicular/métodos , Perda do Osso Alveolar/patologia , Animais , Dente Pré-Molar/patologia , Tecido Conjuntivo/efeitos dos fármacos , Tecido Conjuntivo/patologia , Exposição da Polpa Dentária/microbiologia , Cães , Lasers Semicondutores/uso terapêutico , Neovascularização Fisiológica/efeitos dos fármacos , Periodontite Periapical/patologia , Tecido Periapical/efeitos dos fármacos , Tecido Periapical/patologia , Ligamento Periodontal/efeitos dos fármacos , Ligamento Periodontal/patologia , Preparo de Canal Radicular/métodos , Reabsorção da Raiz/patologia , Fatores de Tempo , Ápice Dentário/efeitos dos fármacos , Ápice Dentário/patologia
15.
Lasers Med Sci ; 27(2): 389-95, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21399951

RESUMO

The aim of this trial was to investigate changes occurring in the subgingival microbiological composition of subjects with aggressive periodontitis, treated with antimicrobial photodynamic therapy (aPDT), in a single episode, or scaling and root planing (SRP), in a split-mouth design on -7, 0, and +90 days. Ten patients were randomly assigned to either aPDT using a laser source in conjunction with a photosensitizer or SRP with hand instruments. Subgingival plaque samples were collected and the counts of 40 subgingival species were determined using checkerboard DNA-DNA hybridization. The data were analyzed using the method of generalized estimating equations (GEE) to test the associations between treatments, evaluated parameters, and experimental times (α = .05). The results indicated that aPDT and SRP affects different bacterial species, with aPDT being effective in reducing numbers of A. actinomycetemcomitans than SRP. On the other hand, SRP was more efficient than aPDT in reducing the presence of periodontal pathogens of the Red Complex. Additionally, a recolonization in the sites treated by aPDT was observed, especially for T. forsythia and P. gingivalis. Under our experimental conditions, this trial demonstrates that aPDT and SRP affected different groups of bacteria, suggesting that their association may be beneficial for the non-surgical treatment of aggressive periodontitis.


Assuntos
Anti-Infecciosos/uso terapêutico , Raspagem Dentária/métodos , Periodontite/tratamento farmacológico , Fotoquimioterapia/métodos , Adolescente , Adulto , Feminino , Humanos , Masculino , Periodontite/microbiologia , Aplainamento Radicular/métodos , Adulto Jovem
16.
Rev. bras. farmacogn ; 19(3): 672-676, jul.-set. 2009. ilus
Artigo em Inglês | LILACS | ID: lil-537908

RESUMO

The ethanolic extract of the trunk bark of Amburana cearensis (EEA) was examined for its oral (p.o.) analgesic activity at the doses of 100, 200 and 400 mg/kg body weight. In the acetic acid-induced writhing test, the EEA (200 and 400 mg/kg, p.o.) reduced the number of writhing by 33.4 percent and 40.7 percent, respectively. Additionally, EEA (100, 200 and 400 mg/kg, p.o.) decreased by 77.5 percent, 79.7 and 91.3 percent, respectively, the paw liking time in the second phase of the formalin test. Therefore, EEA showed a dose-dependent analgesic effect in formalin test and was effective in reducing writhing in mice.


O extrato etanólico da entrecasca de A. cearensis (EEA) foi avaliado em modelos experimentais de nocicepção. No teste das contorções abdominais induzidas pelo ácido acético o EEA (200 e 400 mg/kg, v.o.) foi significativamente efetivo em inibir o estímulo álgico (33,4 por cento e 40,7 por cento), respectivamente, em relação aos animais do grupo controle. O EEA, em todas as doses, promoveu uma redução significativa do tempo de lambidas das patas na segunda fase do teste da formalina (77,5 por cento; 79,7 e 91,3 por cento). Os resultados sugerem uma ação antinociceptiva do EEA.

17.
Int J Oral Maxillofac Implants ; 24(2): 257-66, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19492641

RESUMO

PURPOSE: The aim of this study was to evaluate, through fluorescence analysis, the effect that different interimplant distances, after prosthetic restoration, will have on bone remodeling in submerged and nonsubmerged implants restored with a "platform switch." MATERIALS AND METHODS: Fifty-six Ankylos implants were placed 1.5 mm subcrestally in seven dogs. The implants were placed so that two fixed prostheses, with three interimplant contacts separated by 1-mm, 2-mm, and 3-mm distances, could be fabricated for each side of the mandible. The sides and the positions of the groups were selected randomly. To better evaluate bone remodeling, calcein green was injected 3 days before placement of the prostheses at 12 weeks postimplantation. At 3 days before sacrifice (8 weeks postloading), alizarin red was injected. The amounts of remodeled bone within the different interimplant areas were compared statistically before and after loading in submerged and nonsubmerged implants. RESULTS: Statistically significant differences existed in the percentage of remodeled bone seen in the different regions. Mean percentages of remodeled bone in the submerged and nonsubmerged groups, respectively, were as follows: for the 1-mm distance, 23.0% +/- 0.05% and 23.1% +/- 0.03% preloading and 27.0% +/- 0.03% and 25.2% +/- 0.04% postloading; for the 2-mm distance, 18.2% +/- 0.05% and 18.1% +/- 0.04% preloading and 21.3% +/- 0.07% and 19.9% +/- 0.03% postloading; for the 3-mm distance, 18.3% +/- 0.03% and 18.3% +/- 0.03% preloading and 18.8% +/- 0.04% and 19.8% +/- 0.04% postloading; for distal-extension regions, 16.6% +/- 0.02% and 17.4% +/- 0.04% preloading and 17.0% +/- 0.04% and 18.4% +/- 0.04% postloading. CONCLUSIONS: Based upon this animal study, loading increases bone formation for submerged or nonsubmerged implants, and the interimplant distance of 1 mm appears to result in more pronounced bone remodeling than the 2-mm or 3-mm distances in implants with a "platform switch."


Assuntos
Processo Alveolar/cirurgia , Remodelação Óssea/fisiologia , Implantação Dentária Endóssea/métodos , Implantes Dentários , Mandíbula/cirurgia , Processo Alveolar/metabolismo , Animais , Implantação Dentária Endóssea/instrumentação , Planejamento de Prótese Dentária , Retenção em Prótese Dentária/instrumentação , Prótese Dentária Fixada por Implante , Cães , Fluoresceínas/metabolismo , Corantes Fluorescentes/metabolismo , Masculino , Mandíbula/anatomia & histologia , Distribuição Aleatória
18.
Int J Oral Maxillofac Implants ; 24(1): 151-4, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19344040

RESUMO

Hopeless retained primary teeth without permanent successors represent a restorative challenge for clinicians, along with esthetic and functional problems for patients. While various treatment approaches for congenitally missing teeth have been proposed, the replacement of a missing tooth with a dental implant offers specific advantages, such as preservation of the alveolar crest and elimination of the need to restore the adjacent teeth, over other options for tooth replacement. The aim of this article was to illustrate the surgical and prosthetic treatment with implants of a patient with primary teeth without permanent successors.


Assuntos
Anodontia/terapia , Implantes Dentários , Dente Decíduo/cirurgia , Adulto , Coroas , Prótese Dentária Fixada por Implante , Estética Dentária , Seguimentos , Humanos , Dente Molar/cirurgia , Planejamento de Assistência ao Paciente , Esfoliação de Dente , Extração Dentária , Alvéolo Dental/cirurgia
19.
Int J Oral Maxillofac Implants ; 23(4): 759-62, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18807575

RESUMO

Immediate loading of dental implants shortens the treatment time and makes it possible to give the patient an esthetic appearance throughout the treatment period. Placement of dental implants requires precise planning that accounts for anatomic limitations and restorative goals. Diagnosis can be made with the assistance of computerized tomographic scanning, but transfer of planning to the surgical field is limited. Recently, novel CAD/CAM techniques such as stereolithographic rapid prototyping have been developed to build surgical guides in an attempt to improve precision of implant placement. The aim of this case report was to show a modified surgical template used throughout implant placement as an alternative to a conventional surgical guide.


Assuntos
Implantação Dentária Endóssea/métodos , Prótese Dentária Fixada por Implante , Prótese Parcial Imediata , Arcada Parcialmente Edêntula/reabilitação , Modelos Anatômicos , Cirurgia Assistida por Computador , Substitutos Ósseos , Implantes Dentários , Análise do Estresse Dentário , Prótese Parcial Temporária , Humanos , Arcada Parcialmente Edêntula/diagnóstico por imagem , Masculino , Maxila , Seio Maxilar/cirurgia , Pessoa de Meia-Idade , Modelos Dentários , Procedimentos Cirúrgicos Pré-Protéticos Bucais , Fotografia Dentária , Fatores de Tempo , Tomografia Computadorizada por Raios X , Suporte de Carga
20.
J Periodontol ; 78(6): 965-73, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17539707

RESUMO

BACKGROUND: The treatment of aggressive periodontitis has always presented a challenge for clinicians, but there are no established protocols and guidelines for the efficient control of the disease. METHODS: Ten patients with a clinical diagnosis of aggressive periodontitis were treated in a split-mouth design study to either photodynamic therapy (PDT) using a laser source with a wavelength of 690 nm associated with a phenothiazine photosensitizer or scaling and root planing (SRP) with hand instruments. Clinical assessment of plaque index (PI), gingival index (GI), bleeding on probing (BOP), probing depth (PD), gingival recession (GR), and relative clinical attachment level (RCAL) were made at baseline and 3 months after treatment with an automated periodontal probe. RESULTS: Initially, the PI was 1.0 +/- 0.5 in both groups. At the 3-month evaluation, the plaque scores were reduced and remained low throughout the study. A significant reduction of GI and BOP occurred in both groups after 3 months (P <0.05). The mean PD decreased in the PDT group from 4.92 +/- 1.61 mm at baseline to 3.49 +/- 0.98 mm after 3 months (P <0.05) and in SRP group from 4.92 +/- 1.14 mm at baseline to 3.98 +/- 1.76 mm after 3 months (P <0.05). The mean RCAL decreased in the PDT group from 9.93 +/- 2.10 mm at baseline to 8.74 +/- 2.12 mm after 3 months (P <0.05), and in the SRP group, from 10.53 +/- 2.30 mm at baseline to 9.01 +/- 3.05 mm after 3 months. CONCLUSION: PDT and SRP showed similar clinical results in the non-surgical treatment of aggressive periodontitis.


Assuntos
Placa Dentária/terapia , Raspagem Dentária , Terapia com Luz de Baixa Intensidade/métodos , Periodontite/terapia , Aplainamento Radicular , Adolescente , Adulto , Placa Dentária/radioterapia , Raspagem Dentária/instrumentação , Feminino , Humanos , Terapia com Luz de Baixa Intensidade/instrumentação , Masculino , Perda da Inserção Periodontal/terapia , Periodontite/microbiologia , Periodontite/radioterapia , Aplainamento Radicular/instrumentação , Estatísticas não Paramétricas , Resultado do Tratamento
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...