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PURPOSE: The composition and properties of resin-based composite materials could affect tooth wear and lead to clinical problems. Therefore, the study objective was to characterize human tooth wear behavior against a bulk-fill restorative (BF) compared to a conventional resin composite (RC) and a CAD/CAM resin nano ceramic (RN). METHODS: Square-shaped specimens of each material were prepared and sub-divided according to the number of testing cycles (n=8): 100,000, 250,000, and 500,000 cycles. An occlusal wear test was performed using a chewing machine with 49 N, 2 Hz, in 37°C distilled water. Human premolar cusps were used as antagonists. Micro-CT and laser scanner were used to scan antagonists and specimens, respectively. Wear volume was assessed using a software and the wear pattern was examined with SEM. Softening in solvent analysis was performed by measuring the materials' Knoop microhardness (KHN) before and after immersion in ethanol. Wear volume data were analyzed with two-way ANOVA and Student-Neuman-Keuls test (α=0.05). RESULTS: For tooth and specimen wear volume, there was statistical significance for material and number of cycles, but not for the interaction between factors. BF resulted in less tooth (p=0.008) and specimen (p=0.030) wear than RN and RC, which were similar (p⟩0.05). Volume loss increased from 100,000 to 500,000 cycles. BF showed the lowest microhardness (KHN1); and %ΔKHN similar to RC, but greater than RN. CONCLUSION: BF induced less volume loss to the tooth than RC and RN, while presenting greater wear resistance. The tooth wear pattern and damage progression were mild for all materials. CLINICAL SIGNIFICANCE: Resin composites show favorable wear behavior, leading to low volume loss and mild structural damage of the tooth. Regular bulk-fill resin composite stands out for its efficient restorative technique, low wear susceptibility and reduced capacity to wear down the tooth.
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AIM: To determine the prevalence of preoperative endodontic pain (PREP) and the incidence of postoperative endodontic pain (POEP), identifying the predictors of PREP and POEP in a southern Brazilian subpopulation, using clinical data from an electronic chart database (ECD). METHODOLOGY: This retrospective observational study included 563 consecutive individuals presenting for root canal treatment (RCT). Patients were treated by undergraduate and graduate students, following standard RCT protocols. Demographic, medical and dental variables were extracted from a pre-structured and standardized ECD. The main outcomes PREP and incident POEP were collected through a 0-10 numeric rating scale, dichotomized as none/mild (<4) or moderate/severe (≥4) pain. Predictive models calculating the prevalence ratios (PR) of PREP and the relative risks (RR) of incident POEP were carried out with Poisson regression analysis, estimating the relationship between clinical factors, PREP and incident POEP. RESULTS: Mean age at baseline was 49.2 ± 17.1 years, with 68.4% women. The prevalence and incidence of moderate/severe PREP and POEP were 44.4% and 3.8%, respectively. RCT intervention significantly reduced PREP (P < 0.001). Multivariate analysis revealed that group of teeth, location (mandibular teeth), pulpitis, necrotic pulp, preoperative swelling and periapical radiolucency were independently associated with moderate/severe PREP, whilst age ≥60 years and root canal retreatments were independent protective factors to PREP (P < 0.05). No demographic, medical or dental variables were associated with POEP, although molar teeth (RR = 4.23, 95%CI = 0.93-19.2, P = 0.056) had a borderline nonsignificant association. CONCLUSIONS: Moderate/severe PREP was independently associated with age, group of teeth, location, preoperative swelling, retreatments and pulp and periapical status. No demographic, medical or dental variable predicted moderate/severe POEP following RCT amongst this subpopulation.
Assuntos
Doenças da Polpa Dentária/fisiopatologia , Doenças da Polpa Dentária/cirurgia , Polpa Dentária/fisiopatologia , Dor Facial/etiologia , Dor Pós-Operatória/etiologia , Tratamento do Canal Radicular/efeitos adversos , Brasil/epidemiologia , Registros Eletrônicos de Saúde , Dor Facial/epidemiologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Dor Pós-Operatória/epidemiologia , Prevalência , Estudos RetrospectivosRESUMO
Water stress can affect the yield in tomato crops and, despite this, there are few types of research aiming to select tomato genotypes resistant to the water stress using physiological parameters. This experiment aimed to study the variables that are related to the gas exchanges and the efficiency in water use, in the selection of tomato genotypes tolerant to water stress. It was done in a greenhouse, measuring 7 x 21 m, in a randomized complete block design, with four replications (blocks), being five genotypes in the F2BC1 generation, which were previously obtained from an interspecific cross between Solanum pennellii versus S. lycopersicum and three check treatments, two susceptible [UFU-22 (pre-commercial line) and cultivar Santa Clara] and one resistant (S. pennellii). At the beginning of flowering, the plants were submitted to a water stress condition, through irrigation suspension. After that CO2 assimilation, internal CO2, stomatal conductance, transpiration, leaf temperature, instantaneous water use efficiency, intrinsic efficiency of water use, instantaneous carboxylation efficiency, chlorophyll a and b, and the potential leaf water (Ψf) were observed. Almost all variables that were analyzed, except CO2 assimilation and instantaneous carboxylation efficiency, demonstrated the superiority of the wild accession, S. pennellii, concerning the susceptible check treatments. The high photosynthetic rate and the low stomatal conductance and transpiration, presented by the UFU22/F2BC1#2 population, allowed a better water use efficiency. Because of that, these physiological characteristics are promising in the selection of tomato genotypes tolerant to water stress.
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Cruzamentos Genéticos , Desidratação/genética , Genótipo , Solanum lycopersicum/fisiologia , Estresse Fisiológico/genética , Água , Produção Agrícola , Solanum lycopersicum/genética , Transpiração Vegetal/genéticaRESUMO
Planting with higher density in sugarcane is one of the practices used to overcome low productivity. However, this planting material is equivalent to 25% of the total cost of production, being one of the main expenses for cultivation. In this sense, the present work aims to evaluate the productivity and economic viability of sugarcane as a function of planting density. The experiment was carried out at Usina Monte Alegre in the municipality of Mamanguape, Paraíba, Brazil, from March 2021 to January 2022 with the variety RB92579. Seven planting density were studied: T1: 7 gems m-1, T2: 10 gems m-1, T3: 12 gems m-1, T4: 11 gems m-1, T5: 15 gems m-1, T6: 17 gems m-1, T7: 24 gems m-1, in randomized blocks with four replications. Growth, productivity and economic viability were evaluated. The highest productivity of cane and sugar, 77.69 ton ha-1 and 10.390 ton ha-1, respectively, was with planting density of 17 and 24 gems-1. While the minimum productivity of cane (61.313 ton ha-1) and sugar (7.924 ton ha-1) was recorded at sowing density of 7 and 11 gems-1. However, cultivation density with 7 and 10 gems m-1 were the ones that provided the highest profitability around 50%, followed by density of 12, 15 and 17 gems m-1 with an average of 45% profit and 11 and 24 gems m-1 with the lowest proportion of profit on average 38%. The cultivation with 17 gems m-1 of cane provides in cane-plant, variety RB92579, greater productivity with a profit rate of 45%, being the most suitable.
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Saccharum , Açúcares , BrasilRESUMO
AIM: To present the case of a maxillary left lateral incisor with Oehlers' type III dens invaginatus in which cone beam computed tomography (CBCT) was used as an adjunctive resource in the diagnosis as well as in the planning and 2-year follow-up of the nonsurgical/surgical treatment. SUMMARY: The tooth had two root canals: a primary (main) canal with vital pulp that appeared to be closed apically and an invaginated canal that was necrotic, wide-open at the portal of exit and associated with a large chronic periapical lesion extending to the apex of the maxillary left central incisor. Radiographic tracking of a sinus tract in the labial gingiva of the affected tooth with a gutta-percha point revealed its origin to be the invagination. The CBCT scans revealed that the periapical radiolucency was significantly larger than seen radiographically as well as an increased thickness of the buccal cortical plate. Conventional root canal treatment of the primary canal was undertaken. As nonsurgical access to the invaginated canal was not possible, endodontic surgery was performed for curettage of the lesion, root-end cavity preparation using ultrasonic tips and root canal filling with white mineral trioxide aggregate (MTA). CBCT scanning after 17 months and clinical and radiographic follow-up after 24 months revealed complete periapical repair and absence of symptoms. KEY LEARNING POINTS: The combination of nonsurgical and surgical treatments produced periapical repair in a tooth with type III dens invaginatus with two root canals. CBCT may aid the diagnosis as well as the management plan and follow-up of teeth with this developmental anomaly.
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Tomografia Computadorizada de Feixe Cônico , Dens in Dente/diagnóstico por imagem , Incisivo/anormalidades , Planejamento de Assistência ao Paciente , Compostos de Alumínio/uso terapêutico , Compostos de Cálcio/uso terapêutico , Criança , Dens in Dente/terapia , Fístula Dentária/diagnóstico por imagem , Fístula Dentária/terapia , Cavidade Pulpar/anormalidades , Cavidade Pulpar/diagnóstico por imagem , Necrose da Polpa Dentária/diagnóstico por imagem , Necrose da Polpa Dentária/terapia , Combinação de Medicamentos , Seguimentos , Humanos , Incisivo/diagnóstico por imagem , Masculino , Óxidos/uso terapêutico , Periodontite Periapical/diagnóstico por imagem , Periodontite Periapical/terapia , Obturação Retrógrada/métodos , Materiais Restauradores do Canal Radicular/uso terapêutico , Preparo de Canal Radicular/métodos , Tratamento do Canal Radicular/métodos , Silicatos/uso terapêuticoRESUMO
OBJECTIVE: Anxiety disorders have been shown to undermine the quality of life of cancer patients. Unfortunately, medical professionals often neglect to screen for anxiety in their patients. The aim of the present study was to describe the prevalence of anxiety in patients awaiting diagnostic procedures in an oncology center waiting room, and to investigate possible relationships between anxiety and demographic and clinical variables. METHODS: A cross-sectional study was performed with 398 patients who completed a self-administered questionnaire containing the Hospital Anxiety and Depression Scale (HADS) and the State-Trait Anxiety Inventory (STAI). RESULTS: Results of the HADS indicated that 38% of participants had anxiety, while data from the STAI showed that 46% had either high state or trait anxiety. The most frequently cited source of anxiety was concern over test results. Age, gender, employment status, and education level were correlated with anxiety. CONCLUSIONS: The prevalence of anxiety is high among patients awaiting diagnostic procedures. Patients in the waiting room should be routinely screened for anxiety. Careful assessment and treatment of anxiety are important components in the care of patients with cancer.
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Ansiedade/epidemiologia , Neoplasias/psicologia , Ansiedade/etiologia , Ansiedade/psicologia , Brasil/epidemiologia , Distribuição de Qui-Quadrado , Intervalos de Confiança , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/diagnóstico , Inventário de Personalidade , Prevalência , Escalas de Graduação Psiquiátrica , Fatores Socioeconômicos , Inquéritos e QuestionáriosRESUMO
OBJECTIVES: To evaluate p63 expression in laryngeal squamous cell carcinoma and its prognostic significance. METHODS: p63 expression was examined by immunohistochemistry and scored in 127 patients with laryngeal squamous cell carcinomas. RESULTS: Sixty-two cases had scored 3, sixty had scored 2, four had scored 1 and one case did not show any expression (48.8, 47.2, 3.1 and 0.8%, respectively). Overall survival was 73.9% at 24 months and 59.5% at 60 months. The disease-free survival was 77.2 and 75.1%, and the disease-specific survival was 79 and 67% at 24 and 60 months, respectively. Uni- and multivariate analysis identified that decreased immunoexpression of protein p63 was a statistically significant factor for the risk of recurrence and death by cancer. CONCLUSIONS: p63 expression was highly prevalent in laryngeal squamous cell carcinomas, and its underexpression was correlated with a worse prognosis.
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Carcinoma de Células Escamosas/metabolismo , Neoplasias Laríngeas/metabolismo , Transativadores/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Feminino , Humanos , Imuno-Histoquímica , Neoplasias Laríngeas/patologia , Neoplasias Laríngeas/cirurgia , Laringectomia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Fatores de TranscriçãoRESUMO
Monolithic zirconia crowns have become very popular; their surface finish is considered a key factor for restoration longevity. While polishing has shown excellent results in vivo, the surface glass infiltration of zirconia may offer superior damage resistance and aesthetic advantages by using tooth-colored glasses. Thus, the purpose of this study is to evaluate the efficacy of polishing and glass infiltration on the wear behavior of monolithic zirconia crowns. The wear behavior of intact natural molar teeth was investigated as a reference. Zirconia crowns were divided into 3 groups: PolZ-sintered then polished; PolGZ-polished in the presintered state and then glass infiltrated and sintered; NoPolGZ-as machined, glass infiltrated and sintered. Crowns were adhesively bonded to a dentin-like abutment. Zirconia crowns and molar teeth ( n = 15) were subjected to contact-slide-liftoff cyclic loading (200 N, 1.25 million cycles) with a steatite sphere ( r = 3 mm) as an antagonist in water. Surface and subsurface damages were investigated with optical and scanning electron microscopies. Wear depth and volume loss were determined with micro-computed tomography. PolGZ and NoPolGZ crowns exhibited shallow wear scars, where material loss remained within the glass/zirconia layer with no visible cracks. Meanwhile, PolZ crowns presented no visible wear damage. Volume loss (mm3) in the steatite antagonist was as follows (mean ± SD): PolZ = 0.022 ± 0.007, PolGZ = 0.011 ± 0.004, and NoPolGZ = 0.014 ± 0.006. Molar teeth yielded no measurable wear on the antagonist, while the wear scar on the teeth was greater than that on zirconia crowns, ranging from 0.07 to 0.35 mm3. The combination of polishing and glass infiltration on the occlusal surface of monolithic zirconia crowns yielded reduced wear on both crown and antagonist.
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Porcelana Dentária , Desgaste de Restauração Dentária , Coroas , Esmalte Dentário , Estética Dentária , Teste de Materiais , Propriedades de Superfície , Microtomografia por Raio-X , ZircônioRESUMO
The ruminant pestiviral species BVDV-1, BVDV-2 and BDV, along with the putative species HoBi-like, may cause substantial economic losses in cattle, sheep and goats. Brazil's large size, variable biomes and wide range of ruminant animal production within different geographic regions suggest that the presence and prevalence of ruminant pestivirus may differ by regions within Brazil. This study investigated the genetic diversity of ruminant pestiviruses and determined the frequency of active infections within two states of the Northeast Region of Brazil, Maranhão and Rio Grande do Norte. Serum samples from 16,621 cattle and 2,672 small ruminants from 569 different herds residing in this region were tested by RT-PCR followed by DNA sequencing. Seventeen positive cattle were detected (0.1%) from fifteen different herds (2.64%). All isolates were classified as HoBi-like pestiviruses based on phylogenetic analysis. All small ruminant samples tested negative. The findings presented herein suggest that the Northeast Region of Brazil has a uniquely high prevalence of HoBi-like viruses. The increasing reports of HoBi-like viruses detected in cattle in the field suggest that natural infection with these viruses may be more widespread than previously thought. The identification of HoBi-like viruses as the most prevalent type of ruminant pestivirus circulating in the Northeast Region of Brazil indicates the need for both continued monitoring and determination of the extent of economic losses associated with HoBi-like virus infections. In addition, it must be taken into account in the choice of diagnostic tests and in vaccine formulations.
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Doenças dos Bovinos/virologia , Vírus da Diarreia Viral Bovina/genética , Variação Genética , Infecções por Pestivirus/veterinária , Animais , Brasil/epidemiologia , Bovinos , Doenças dos Bovinos/epidemiologia , Vírus da Diarreia Viral Bovina Tipo 1/classificação , Vírus da Diarreia Viral Bovina Tipo 1/genética , Vírus da Diarreia Viral Bovina Tipo 1/isolamento & purificação , Vírus da Diarreia Viral Bovina Tipo 2/classificação , Vírus da Diarreia Viral Bovina Tipo 2/genética , Vírus da Diarreia Viral Bovina Tipo 2/isolamento & purificação , Vírus da Diarreia Viral Bovina/classificação , Vírus da Diarreia Viral Bovina/isolamento & purificação , Infecções por Pestivirus/epidemiologia , Infecções por Pestivirus/virologia , Filogenia , Prevalência , Ruminantes , Análise de Sequência de DNA/veterináriaRESUMO
OBJECTIVE: This study investigated the influence of the cooling protocol on the mechanical behavior of Y-TZP veneered with porcelain with different compositions. The tested hypotheses were: (1) Y-TZP infrastructures veneered with porcelain containing leucite in its composition presents higher flexural strength (σ) and reliability (m), and (2) slow cooling protocol results in greater σ and m. METHODS: A total of 120 bilayer porcelain-Y-TZP bar-shaped specimens were prepared with the dimensions of 1.8mm (0.8mm Y-TZP±1.0mm porcelain)×4.0mm×16.0mm. Specimens were divided into four groups (n=30) according to the porcelain composition (containing or not leucite) and cooling protocol. Fast cooling was performed by opening the furnace chamber at sintering temperature. For the slow cooling, the chamber was maintained closed until it reached the room temperature. Specimens were tested in three-point bending with the porcelain surface under tension using a universal testing machine, in 37°C water, at 0.5mm/min crosshead speed. Data were analyzed by two-way ANOVA, Tukey post-hoc test (α=0.05) and Weibull. RESULTS: Y-TZP veneered with porcelains with different microstructural composition presented similar σ and m values (p=0.718). The cooling protocol had no influence on the σ and m values of the experimental groups (p=0.718). Cracking represented 95% of failures, whereas the initial flaw propagated from the porcelain surface towards the interface. SIGNIFICANCE: Y-TZP veneered with porcelain containing or not leucite present similar mechanical behavior and, at 1-mm thickness, is not sensitive to the cooling protocol.
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Facetas Dentárias , Zircônio , Silicatos de Alumínio , Porcelana Dentária , Teste de Materiais , Reprodutibilidade dos Testes , Propriedades de SuperfícieRESUMO
OBJECTIVES: To estimate the reliability and failure behavior of fixed partial dentures (FPDs) fabricated using the CAD-on technique. METHODS: FPDs (n=25) were fabricated using a CAD/CAM system: IPS e.max ZirCAD - Crystall./Connect and IPS e.max CAD (Ivoclar). The restoration type ("three-unit bridge") and design method ("multilayer") based on Biogenerics were used. Framework and porcelain structures were united using a fusion ceramic (Crystall./Connect, Ivoclar). Mechanical fatigue was tested in a servohydraulic load frame machine at a cyclic loading (frequency: 2Hz; load ratio: 0.1). Based on previous data from specimens tested in fast fracture, three different stress profiles were used. The lifetime data were analyzed using an inverse power law-Weibull cumulative damage model (ALTA PRO, Reliasoft). All failed specimens were examined under a field emission scanning electron microscope. RESULTS: Porcelain chipping was the predominant (60%) mode of failure for FPDs tested in fast fracture and connector failure was predominant (67%) under fatigue. For fast fracture data, the Weibull modulus (ß) of FPDs was 7.8 combining the two failure modes. When chipping and connector fracture data were analyzed separately, ß values were 7.9 and 2.9. For the step stress fatigue test, ß values were lower than estimated using fast fracture, being 1.6 for connector fracture and 1.3 for porcelain chipping. SIGNIFICANCE: The test method (fast fracture or fatigue) significantly influenced the reliability of FPDs fabricated using the CAD-on technique, but it did not influence their failure behavior.
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Falha de Restauração Dentária , Prótese Parcial Fixa , Cerâmica , Desenho Assistido por Computador , Porcelana Dentária , Análise do Estresse Dentário , Teste de Materiais , Reprodutibilidade dos Testes , Estresse Mecânico , ZircônioRESUMO
OBJECTIVE: To evaluate the flexural strength, Weibull modulus, fracture toughness, and failure behavior of ceramic structures obtained by the CAD-on technique, testing the null hypothesis that trilayer structures show similar properties to monolithic structures. METHODS: Bar-shaped (1.8mm×4mm×16mm) monolithic specimens of zirconia (IPS e.max ZirCAD - Ivoclar Vivadent) and trilayer specimens of zirconia/fusion ceramic/lithium dissilicate (IPS e.max ZirCAD/IPS e.max CAD Crystall./Connect/IPS e.max CAD, Ivoclar Vivadent) were fabricated (n=30). Specimens were tested in flexure in 37°C deionized water using a universal testing machine at a crosshead speed of 0.5mm/min. Failure loads were recorded, and the flexural strength values were calculated. Fractography principles were used to examine the fracture surfaces under optical and scanning electron microscopy. Data were statistically analyzed using Student's t-test and Weibull statistics (α=0.05). RESULTS: Monolithic and trilayer specimens showed similar mean flexural strengths, characteristic strengths, and Weibull moduli. Trilayer structures showed greater mean critical flaw and fracture toughness values than monolithic specimens (p<0.001). Most critical flaws in the trilayer groups were located on the Y-TZP surface subjected to tension and propagated catastrophically. Trilayer structures showed no flaw deflection at the interface. SIGNIFICANCE: Considering the CAD-on technique, the trilayer structures showed greater fracture toughness than the monolithic zirconia specimens.
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Cerâmica/química , Desenho Assistido por Computador , Porcelana Dentária/química , Zircônio/química , Análise do Estresse Dentário , Módulo de Elasticidade , Teste de Materiais , Microscopia Eletrônica de Varredura , Maleabilidade , Reprodutibilidade dos Testes , Estresse Mecânico , Propriedades de SuperfícieRESUMO
Bioelectrical impedance analysis (BIA) is regarded as an important tool for evaluating the body composition of different animals in a rapid, non-destructive, and low-cost manner. A South American fish species, Steindachneridion scriptum, known as suruvi, was selected for study in this investigation. A protocol to produce fish with different body composition was used to allow BIA to adequately predict the body composition of suruvi. The fish were fed twice each day with two different diets; a low lipid diet (8.90%), and a high lipid diet (18.68%). These dietary differences allowed suruvi specimens with different body compositions to be produced. The BIA readings were determined using a Quantum X Bioelectrical Body Composition Analyzer. Two readings (dorsal and ventral) were obtained for each fish. After BIA readings were obtained, the proximate composition of the fish bodies for each individual was determined. All of the study data were used to establish correlation equations between proximate analyses and BIA values. Strong correlations were found for S. scriptum. The highest correlations were obtained for the following pairs of quantities, using BIA data from dorsal readings: moisture and resistance in series (R2 = 0.87); protein and resistance in series (R2 = 0.87); and ash and reactance in parallel (R2 = 0.82). We conclude that BIA is an effective method in determining the body composition of S. scriptum without sacrificing the fish. However, to expand the use of this new technology it is important to define strict BIA protocols to guarantee accurate estimates.
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Composição Corporal , Peixes-Gato/fisiologia , Impedância Elétrica , Animais , AquiculturaRESUMO
This survey was conducted in the southern Brazilian state of Rio Grande do Sul and involved 182 farms located in 26 counties. In addition to the three major broad-spectrum anthelmintic groups (viz. benzimidazole, levamisole and ivermectin) the combination benzimidazole and levamisole and the H. contortus specific anthelmintic, closantel, were tested by the faecal egg count reduction method for the prevalence of anthelmintic resistance. Resistance was found to be 90%, 84%, 13%, 73% and 20%, respectively. This is a crisis situation. Immediate, drastic action needs to be implemented, otherwise the sheep industry in this region (approx. 10 million head) will soon face a lack of any effective anthelmintics with the inevitable consequences of major restructuring or abandonment.
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Anti-Helmínticos/uso terapêutico , Resistência a Múltiplos Medicamentos , Nematoides/efeitos dos fármacos , Infecções por Nematoides/veterinária , Doenças dos Ovinos , Ovinos/parasitologia , Animais , Brasil , Clima , Demografia , Infecções por Nematoides/tratamento farmacológico , Estações do Ano , TemperaturaRESUMO
Two groups of 33 helminth-naive lambs were infected with 5,000 L3 of an ivermectin-resistant or -susceptible strain of Haemonchus contortus (groups R and S). On days 6, 10, 16, and 21 postinfection, 5 animals from each group were chosen at random and orally treated with 0.2 mg/kg of ivermectin. On each occasion, 2 randomly selected lambs from each group were also killed to determine the number and stage of development of the worms present at the time of treatment. These necropsies revealed that by day 6 early and late fourth-stage larvae were present, whereas on day 10 the early fifth stage had been reached; by days 16 and 21 all worms had reached the adult stage. Necropsies on day 28 postinfection revealed that although animals treated at day 6 had 26.3% fewer worms than the controls, there was no significant difference (P greater than 0.05) between worm burdens from any of the animals infected with the R strain and treated at different times after infection when compared with the untreated controls. With ivermectin significant reductions were obtained in the worm burdens of the animals infected with the susceptible strain; these were reduced by 96% when treatment was given on day 6 against fourth-stage larvae and 98.9% when the drug was given on day 21 against adult stages. From these results it is clear that resistance to ivermectin in this strain of H. contortus is present as early as the fourth larval stage.
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Hemoncose/veterinária , Haemonchus/efeitos dos fármacos , Ivermectina/uso terapêutico , Doenças dos Ovinos/tratamento farmacológico , Animais , Resistência a Medicamentos , Hemoncose/tratamento farmacológico , Ivermectina/farmacologia , Larva/efeitos dos fármacos , Masculino , Distribuição Aleatória , OvinosRESUMO
The free-living development of three strains of Haemonchus contortus was studied in two experiments. Day 21 faecal samples were collected from lambs infected with either a susceptible strain, a laboratory-selected ivermectin (IVM) resistant strain or a South African field strain showing multiple anthelmintic resistance, which included IVM. No eggs hatched in samples cultured at 4 or 10 degrees C. At 22 degrees C the laboratory-selected strain showed the highest rate of development while at 27 degrees C the susceptible strain produced the highest yield of third stage larvae (L3): at both temperatures the field strain showed the lowest percentage development to L3. The second experiment was a field study carried out in southern Brazil. Faeces containing either an IVM-susceptible or an IVM-resistant strain of H contortus were placed in two series of grass plots during each of three summer months. Soil subsequently yielded more larvae than did grass suggesting migration or mechanical transport into the soil. For plots contaminated during the first two months there was no significant difference in recovery rate between the two strains (P > 0.05). When contamination occurred during the third month, the IVM-resistant strain produced significantly higher recovery rates (P < 0.05) from both pasture and soil.
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Hemoncose/veterinária , Haemonchus/efeitos dos fármacos , Ivermectina/uso terapêutico , Doenças dos Ovinos/parasitologia , Animais , Resistência a Medicamentos , Fezes/parasitologia , Hemoncose/tratamento farmacológico , Técnicas Microbiológicas/veterinária , Contagem de Ovos de Parasitas , Ovinos , Doenças dos Ovinos/tratamento farmacológico , Microbiologia do SoloRESUMO
The effects of fluoride ingestion (3.5 mg/kg of body weight) were evaluated in 9 ewes at 6 through 9, 10 through 13, or 14 through 17 months of age (3 ewes/age group). In the 3 groups, the plasma fluoride concentration rapidly increased to 0.45, 0.46, and 0.50 microgram/ml, respectively, and decreased rapidly to 0.1 microgram/ml after fluoride was removed from the ration. In 5 of the 9 ewes, this short-term exposure caused symmetrical, moderate damage to the molars, which is characteristic of fluorosis in sheep. In 7 of the 9 ewes, abnormal gaps were found between incisors, which are not characteristic of fluorosis in sheep. Fluoride accumulation was higher in the roots of the incisors and in the dentine of the molars and was particularly evident in teeth that were developing when fluoride was administered; however, the fully developed teeth and teeth that developed several months after administration of fluoride also were affected. The increase in fluoride concentration in the enamel was confined to a maximum of 2 molars. The abnormal wear of the molars was not directly linked to fluoride accumulation.
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Fluoretos/toxicidade , Fluorose Dentária/veterinária , Doenças dos Ovinos/induzido quimicamente , Animais , Feminino , Fluoretos/metabolismo , Ovinos , Dente/metabolismoRESUMO
Colonoscopy is employed in prevention, diagnosis, follow-up and treatment of colorectal diseases. The technological advancement of colonoscopes and supplementary equipment, has broadened indications for colonoscopy. However, since it is an invasive method with potential complications and hazards it should be performed by specialists capable of preventing, recognizing and treating them. The authors report their personal experience with 1,234 colonoscopies. The most frequent indications were changes in bowel habits and rectal bleeding in 35.1% and 30.5% cases respectively. The patients were given 10% mannitol for bowel cleansing and inadequate bowel cleansing in only 15 (1.2%) so that the colonoscopy could not be completed. The overall incidence of perforation was 0.16%. Three hundred and one polypectomies were performed and two cases (0.75%) of bleeding were noted.
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Colonoscopia , Enteropatias/diagnóstico , Adolescente , Adulto , Idoso , Criança , Humanos , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
The authors present their experience with 924 colonoscopic polypectomies in 549 patients. Postpolypectomy bleeding was 0.36% without perforations. Complications associated with the procedure are analyzed; evaluating the risk, diagnosis and treatment based on a survey of the literature and personal experience.
Assuntos
Pólipos do Colo/cirurgia , Adolescente , Adulto , Idoso , Criança , Colonoscopia/métodos , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Cirurgia VídeoassistidaRESUMO
PURPOSE: To evaluate if fever is an objective criterion in the assessment of response to antibiotic therapy and in the prognosis of patients undergoing treatment for infective endocarditis (IE). METHODS: Fifty-eight cases of IE, occurring from January 1980 to December 1989 have been analysed retrospectively in this study. Emphasis was given to the clinical history and body temperature changes during the first five weeks of treatment. Patients were divided in three groups according to the number of febrile peaks per week. Temperature was assessed weekly from each patient's highest peak weighed average. RESULTS: At the first exam, 52 patients (86.2%) presented fever. All patients had at least one episode of fever during their hospitalization. There seemed to be a relation between the number of febrile peaks during a one week period and the mean body temperature, so that these patients who presented four or more peaks in a week had a higher mean body temperature than those with two or less febrile peaks during the week. After the second week of treatment, patients with two or less febrile peaks had a 93.1% survival and average of 35.5 days of hospitalization, whereas those with three or more febrile peaks had 63.6% survival and an average of 47.5 days of hospitalization. CONCLUSION: The results of this study show that the intensity of fever is linked to the number of febrile peaks per week, regardless to treatment duration. Should there be three or more febrile peaks weekly after the second week of treatment, therapeutic strategy should be reviewed, considering even surgical treatment. In many cases, the persistence of fever represented the clinical expression of complications which determined a higher mortality rate and a longer hospitalization.