657 resultados para Necrotic pulps


Relevância:

10.00% 10.00%

Publicador:

Resumo:

PURPOSE: To report a case of Nocardia asteroides scleritis in a patient without risk factors for infeccious scleritis. METHODS: A 38-year old woman was initially examined for pain, discharge, photophobia of 1 month duration in her right eye. Her medical and ophthalmological history were unremarkable. The results of laboratory tests were normal. Surgical debridement of necrotic tissue was performed and material was sent for biopsy and culture confirmed as Nocardia asteroides. Treatment consisted of amikacin eyedrops, and systemic trimethropim-sulfamethoxazole. The infection resolved leaving scleral thinning and a subconjunctival fibrovascular scar. Best corrected visual acuity two months after referral had improved to LE, 20/20. CONCLUSION: Prompt evaluation and treatment is essential for successful management of Nocardia asteroides infectious scleritis.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Central nervous system involvement in Candida septicaemia is rare and not more than four cases have been published in Brazil. Five new cases of systemic candidiasis with cerebral lesions are reported. All patients (four adults and a child) had serious underlying diseases and were submitted to heavy long-term antibiotic therapy with multiple drugs. Seizures in one case and neck stiffness in another were the only neurologic signs that could be attributed to candidiasis. In no case were the lesions severe enough to be considered an immediate cause of death. In three patients, no macroscopic changes were evident in the brain, but microabscesses and granulomata were observed on microscopical examination; another patient had two gross areas with necrotic and haemorrhagic appearance in the cerebral hemispheres; the child had only two microscopic granulomata. The aetiological agent was demonstrated by Grocott's methenamine silver technique in all cases. Involvement of organs other than the central nervous system could be demonstrated in three autopsies. Discussion is confined mainly to such aspects as the contributory factors in the pathogenesis of systemic candidiasis as well as the marked rise in the incidence of this condition in the past few decades. It is suggested that the frequence of monilial septicaemia in Brazil may be far more serious than apparent from the scarcity of reported cases.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

A 6 month-old mulatto boy was admitted on account of acute gastroenteritis, malnutrition and dehydration. In the hospital, the child developed septicemia, and temperature reached up to 38.6°C. Despite intensive antibiotic treatment, the patient died 12 days after admission. Necropsy disclosed bilateral bronchopneumonia, bilateral fronto-parietal subarachnoid hemorrhage, and extensive necrosis of the inferior half of both cerebellar hemispheres. On histopathological examination of the necrotic cerebellar cortex, numerous sickled erythrocytes were observed in petechial hemorrhages and, in lesser quantities, inside capillaries. Lesions of the central nervous system in sickle cell anemia most often involve the cerebral cortex, and a single extensive cerebellar infarction as present in this case seems extremely rare. The pathogenetic mechanism of the necrosis is unclear, since thrombosis was not observed either in large blood vessels or in capillaries. Possible contributory factors were the infectious condition (septicemia), fever, and anoxia caused by the extensive bronchopneumonia.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

A case of brain abscess and meningitis due to pigmented fungi is reported. The patient was a 59-year-old white male, who had enjoyed excellent health until October 1977, when he developed headache, later accompanied by paresthesias and weakness in the left-sided extremities. These symptoms worsened progressively and in November of that year he had to quit his job. From February 1978 on he became inactive and anorexic. Intense continuous headache was associated with frequent episodes of vomiting. He gradually became tor-porous, and according to his relatives, suffered from visual and possibly auditory deficiency. On examination, he was malnourished and dehydrated, with decubitus ulcers. Temperature was 38,5°C. A left-sided spastic hemiplegia and prominent meningorradicular signs were noted. The CSF was examined six times between May 17th and June 1st and showed variable hypercytosis (143 to 4,437 leucocytes/ cu mm) with predominance of neutrophils (up tp 95%), low glucose and high protein concentrations. No microorganisms were identified. Electroencephalographic study disclosed a low background activity especially in left temporal areas. Despite supportive care and antibiotic therapy he lapsed into coma. Carotid angiography was normal on June 1st. He remained in deep coma until his death on June 6th, 1978. Necropsy was limited to the brain, which weighed 1,550 g after fixation and showed diffuse intense edema and hyperemia. On coronal sectioning an encapsulated abscess was found in the right basal ganglia, which also involved the internal capsule, and measured 1.5 cm in diameter. Microscopical examination disclosed large numbers of brownish fungi, appearing both as oval yeasts and as septate hyphae in the thick fibrous capsule and in the necrotic content of the abscess. The same organisms were demonstrated in moderate numbers in the leptomeninges of the medulla oblongata and , less frequently, of the hippo-campal region and cerebellum.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The case of a 15 years old white man, diabetic in cetoacidosis, with a orbit-rhino-cerebral phycomycosis is reported. The illness had an acute onset and the treatment was iniciated early with Amphotericin-B and unilateral osteotomy of maxillary and ethmoidal sinus. With this treatment the patient did well with residuals of ophtalmoplegia and amaurosis on the right. Interesting investigation aspects are the occluded internal carotid on the same side of the affected orbit and the CAT-SCAN finding of moderated ventricular dilatation (two month after hospital admission). Mycology, pathophysiology, histopathology, clinical aspects, diagnosis and therapy are discussed, comparing the findings of this case with available literature. An increased number of survivors can be expected with earlier recognition and more aggressive therapy. Treatment of the underlying debilitating disease, Amphotericin-B and surgical debridement of necrotic tissue, are frequently necessary such as observed in the case reported. The favorable results ootaineü with the proposed managment are stressed.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Root canal treatment is a frequently performed dental procedure and is carried out on teeth in which irreversible pulpitis has led to necrosis of the dental pulp. Removal of the necrotic tissue remnants and cleaning and shaping of the root canal are important phases of root canal treatment. Treatment options include the use of hand and rotary instruments and methods using ultrasonic or sonic equipment. OBJECTIVES: The objectives of this systematic review of randomized controlled trials were to determine the relative clinical effectiveness of hand instrumentation versus ultrasonic instrumentation alone or in conjunction with hand instrumentation for orthograde root canal treatment of permanent teeth. MATERIAL AND METHODS: The search strategy retrieved 226 references from the Cochrane Oral Health Group Trials Register (7), the Cochrane Central Register of Controlled Trials (CENTRAL) (12), MEDLINE (192), EMBASE (8) and LILACS (7). No language restriction was applied. The last electronic search was conducted on December 13th, 2007. Screening of eligible studies was conducted in duplicate and independently. RESULTS: Results were to be expressed as fixed-effect or random-effects models using mean differences for continuous outcomes and risk ratios for dichotomous outcomes with 95% confdence intervals. Heterogeneity was to be investigated including both clinical and methodological factors. No eligible randomized controlled trials were identifed. CONCLUSIONS: This review illustrates the current lack of published or ongoing randomized controlled trials and the unavailability of high-level evidence based on clinically relevant outcomes referring to the effectiveness of ultrasonic instrumentation used alone or as an adjunct to hand instrumentation for orthograde root canal treatment. In the absence of reliable research-based evidence, clinicians should base their decisions on clinical experience, individual circumstances and in conjunction with patients' preferences where appropriate. Future randomized controlled trials might focus more closely on evaluating the effectiveness of combinations of these interventions with an emphasis on not only clinically relevant, but also patient-centered outcomes.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The present work describes non-conventional sisal (Agave sisalana) chemical (organosolv) pulp from residues of cordage as reinforcement to cement based materials. Sisal organosolv pulp was produced in a 1:1 ethanol/water mixture and post chemically and physically characterized in order to compare its properties with sisal kraft pulp. Cement based composites reinforced with organosolv or kraft pulps and combined with polypropylene (PP) fibres were produced by the slurry de-watering and pressing method as a crude simulation of the Hatschek process. Composites were evaluated at 28 days of age, after exposition to accelerated carbonation and after 100 soak/dry cycles. Composites containing organosolv pulp presented lower mechanical strength, water absorption and apparent porosity than composites reinforced with kraft pulp. The best mechanical performance after ageing was also achieved by samples reinforced with kraft pulp. The addition of PP fibres favoured the maintenance of toughness after ageing. Accelerated carbonation promoted the densification of the composites reinforced with sisal organosolv + PP fibres.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Características físico-químicas (cor, pH, acidez total titulável, sólidos solúveis totais, conteúdo de lipídios e umidade) e níveis de compostos bioativos (ácido ascórbico, fenólicos totais) foram determinados em quinze amostras de polpas de frutos procedentes da região Amazônica (abiu, acerola, açaí, araçá-boi, bacaba, bacuri, buriti, cajá, cajarana, caju, cupuaçu, graviola, murici, noni e tamarindo). A atividade de radicais livres foi avaliada pelo método de ABTS. Algumas polpas apresentaram alta potencialidade antioxidante, associada com a atividade antirradicais livres obtida e os conteúdos dos componentes bioativos como compostos fenólicos e ácido ascórbico, destacando-se acerola e acaí. O conteúdo total de compostos fenólicos foi correlacionado à capacidade antioxidante das polpas.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

A Meningoencefalite Necrotizante (MEN) é uma encefalopatia causada por uma disfunção inflamatória de característica necrotizante. O objetivo deste relato é descrever os aspectos clínicos e anatomopatológicos da Meningoencefalite Necrotizante (MEN) em um cão Maltês. A doença tem um caráter necrótico único e está relacionada intimamente à Encefalite do Cão Pug (ECP) devido a suas semelhanças, bem como à Leucoencefalite Necrotizante (LEN). Embora o primeiro relato de caso de ECP tenha mais de 15 anos e o primeiro relato de caso de MEN em Maltês tenha 11 anos, há muito a ser revelado sobre a etiologia e os mecanismos imunopatológicos da doença. Neste trabalho, relata-se o caso de um cão Maltês com sinais que foram compatíveis com a MEN. Foram detectadas nas imagens macroscópicas, cavitação cerebral, e na microscopia, perda de células do parênquima em certas regiões do córtex cerebral. A partir dessas descobertas descreve-se o primeiro caso de MEN em cão Maltês no Brasil.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Descreve-se um surto de disenteria de inverno que afetou 10 vacas leiteiras de uma propriedade localizada em Viamão, Rio Grande do Sul. O quadro clínico caracterizou-se por uma diarréia inicialmente líquida esverdeada com estrias de sangue e muco, evoluindo, em alguns animais, para uma diarréia de coloração marrom escura à sanguinolenta, que persistiu, em média, cinco dias. Drástica diminuição na produção de leite e no consumo de alimentos, além de graus variados de depressão também foram observados. Apenas um dos 10 animais afetados morreu. Durante a necropsia, observaram-se mucosas pálidas, conteúdo sanguinolento com presença de grande quantidade de coágulos, principalmente no cólon espiral e petéquias na mucosa do cólon. Os principais achados histológicos foram encontradas no cólon espiral, onde havia criptas dilatadas, sem epitélio de revestimento ou revestidas por epitélio pavimentoso e/ou cuboidal, por vezes com núcleos grandes e nucléolos proeminentes. Algumas criptas eram preenchidas por debris necróticos e polimorfonucleares. Na imuno-histoquímica com anticorpo monoclonal para coronavírus bovino (8F2) em cortes do cólon espiral, havia marcações positivas no citoplasma de enterócitos das criptas, nos debris necróticos destas e em macrófagos na lâmina própria.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Background Data: Photodynamic therapy (PDT) involves the photoinduction of cytotoxicity using a photosensitizer agent, a light source of the proper wavelength, and the presence of molecular oxygen. A model for tissue response to PDT based on the photodynamic threshold dose (Dth) has been widely used. In this model cells exposed to doses below Dth survive while at doses above the Dth necrosis takes place. Objective: This study evaluated the light Dth values by using two different methods of determination. One model concerns the depth of necrosis and the other the width of superficial necrosis. Materials and Methods: Using normal rat liver we investigated the depth and width of necrosis induced by PDT when a laser with a gaussian intensity profile is used. Different light doses, photosensitizers (Photogem, Photofrin, Photosan, Foscan, Photodithazine, and Radachlorin), and concentrations were employed. Each experiment was performed on five animals and the average and standard deviations were calculated. Results: A simple depth and width of necrosis model analysis allows us to determine the threshold dose by measuring both depth and surface data. Comparison shows that both measurements provide the same value within the degree of experimental error. Conclusion: This work demonstrates that by knowing the extent of the superficial necrotic area of a target tissue irradiated by a gaussian light beam, it is possible to estimate the threshold dose. This technique may find application where the determination of Dth must be done without cutting the tissue.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Biopulping fundamentals, technology and mechanisms are reviewed in this article. Mill evaluation of Eucalyptus grandis wood chips biotreated by Ceriporiopsis subvermispora on a 50-tonne pilot-plant demonstrated that equivalent energy savings can be obtained in lab- and mill-scale biopulping. Some drawbacks concerning limited improvements in pulp strength and contamination of the chip pile with opportunist fungi have been observed. The use of pre-cultured wood chips as inoculum seed for the biotreatment process minimized contamination problems related to the use of blended mycelium and corn-steep liquor in the inoculation step. Alkaline wash restored part of the brightness in biopulps and marketable brightness values were obtained by one-stage bleaching with 5% H2O2 when bio-TMP pulps were under evaluation. Considering the current scenario, the understanding of biopulping mechanisms has gained renewed attention because more resistant and competitive fungal species could be selected with basis on a function-directed screening project. A series of studies aimed to elucidate structural changes in lignin during wood biodegradation by C. subvermispora had indicated that lignin depolymerization occurs during initial stages of wood biotreatment. Aromatic hydroxyls did not increase with the split of aryl-ether linkages, suggesting that the ether-cleavage-products remain as quitione-type structures. On the other hand, cellulose is more resistant to the attack by C subvermispora. MnP-initiated lipid peroxidation reactions have been proposed to explain degradation of non-phenolic lignin substructures by C subvermispora, while the lack of cellobiohydrolases and the occurrence of systems able to suppress Fenton`s reaction in the cultures have explained non-efficient cellulose degradation by this biopulping fungus. (C) 2007 Elsevier Inc. All rights reserved.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The effects of alkaline treatments of the wheat straw with sodium hydroxide were investigated. The optimal condition for extraction of hemicelluloses was found to be with 0.50 mol/l sodium hydroxide at 55C for 2 h. This resulted in the release of 17.3% of hemicellulose (% dry starting material), corresponding to the dissolution of 49.3% of the original hemicellulose. The yields were determined by gravimetric analysis and expressed as a proportion of the starting material. Chemical composition and physico-chemical properties of the samples of hemicelluloses were elucidated by a combination of sugar analyses, Fourier transform infrared (FTIR), and thermal analysis. The results showed that the treatments were very effective on the extraction of hemicelluloses from wheat straw and that the extraction intensity (expressed in terms of alkali concentration) had a great influence on the yield and chemical features of the hemicelluloses. The FTIR analysis revealed typical signal pattern for the hemicellulosic fraction in the 1,200-1,000 cm(-1) region. Bands between 1,166 and 1,000 cm(-1) are typical of xylans.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

In biopulping, efficient wood colonization by a selected white-rot fungus depends on previous wood chip decontamination to avoid the growth of primary molds. Although simple to perform in the laboratory, in large-scale biopulping trials, complete wood decontamination is difficult to achieve. Furthermore, the use of fungal growth promoters such as corn steep liquor enhances the risk of culture contamination. This paper evaluates the ability of the biopulping fungus Ceriporiopsis subvermispora to compete with indigenous fungi in cultures of fresh or poorly decontaminated Eucalyptus grandis wood chips. While cultures containing autoclaved wood chips were completely free of contaminants, primary molds grew rapidly when non-autoclaved wood chips were used, resulting in heavily contaminated cultures, regardless of the C. subvermispora inoculum/wood ratio evaluated (5, 50 and 3000 mg mycelium kg(-1) wood). Studies on benomyl-amended medium suggested that the fungi involved competed by consumption of the easily available nutrient sources, with C. subvermispora less successful than the contaminant fungi. The use of acid-washed wood chips decreased the level of such contaminant fungi, but production of manganese peroxidase and xylanases was also decreased under these conditions. Nevertheless, chemithermomechanical pulping of acid-washed samples biotreated under non-aseptic conditions gave similar fibrillation improvements compared to samples subjected to the standard biodegradation process using autoclaved wood chips.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The effect of different culture conditions have been evaluated concerning the extracellular enzyme activities of the white-rot fungus Ceriporiopsis subvermispora growing on Eucalyptus grandis wood. The consequence of the varied fungal pretreatment on a subsequent chemithermomechanical pulping (CTMP) was addressed. In all cultures, manganese peroxidase (MnP) and xylanase were the predominant extracellular enzymes. The biopulping efficiency was evaluated based on the amount of fiber bundles obtained after the first fiberizing step and the fibrillation levels of refined pulps. It was found that the MnP levels in the cultures correlated positively with the biopulping benefits. On the other hand, xylanase and total oxalate levels did not vary significantly. Accordingly, it was not possible to determine whether MnP accomplishes the effect alone or depends on synergic action of other extracellular agents. Pulp strength and fiber size distribution were also evaluated. The average fiber length of CTMP pulps prepared from untreated wood chips was 623 mu m. Analogous values were observed for most of the biopulps; however, significant amounts of shorter fibers were found in the biopulp prepared from wood chips biotreated in cultures supplemented with glucose plus corn-steep liquor. Despite evidence of reduced average fiber length, biopulps prepared from these wood chips presented the highest improvement in tensile indexes (+28% at 23 degrees Schopper-Riegler).