RESUMO
The ability of clothing to provide protection against external environments is critical for wearer's safety and thermal comfort. It is a function of several factors, such as external environmental conditions, clothing properties and activity level. These factors determine the characteristics of the different microclimates existing inside the clothing which, ultimately, have a key role in the transport processes occurring across clothing. As an effort to understand the effect of transport phenomena in clothing microclimates on the overall heat transport across clothing structures, a numerical approach was used to study the buoyancy-driven heat transfer across horizontal air layers trapped inside air impermeable clothing. The study included both the internal flow occurring inside the microclimate and the external flow occurring outside the clothing layer, in order to analyze the interdependency of these flows in the way heat is transported to/from the body. Two-dimensional simulations were conducted considering different values of microclimate thickness (8, 25 and 52 mm), external air temperature (10, 20 and 30 °C), external air velocity (0.5, 1 and 3 m s(-1)) and emissivity of the clothing inner surface (0.05 and 0.95), which implied Rayleigh numbers in the microclimate spanning 4 orders of magnitude (9 × 10(2)-3 × 10(5)). The convective heat transfer coefficients obtained along the clothing were found to strongly depend on the transport phenomena in the microclimate, in particular when natural convection is the most important transport mechanism. In such scenario, convective coefficients were found to vary in wavy-like manner, depending on the position of the flow vortices in the microclimate. These observations clearly differ from data in the literature for the case of air flow over flat-heated surfaces with constant temperature (which shows monotonic variations of the convective heat transfer coefficients, along the length of the surface). The flow patterns and temperature fields in the microclimates were found to strongly depend on the characteristics of the external boundary layer forming along the clothing and on the distribution of temperature in the clothing. The local heat transfer rates obtained in the microclimate are in marked contrast with those found in the literature for enclosures with constant-temperature active walls. These results stress the importance of coupling the calculation of the internal and the external flows and of the heat transfer convective and radiative components, when analyzing the way heat is transported to/from the body.
Assuntos
Vestuário , Microclima , Modelos Teóricos , Convecção , Humanos , TemperaturaAssuntos
Anafilaxia/epidemiologia , Anafilaxia/etiologia , Ácido Clavulânico/efeitos adversos , Hipersensibilidade a Drogas/epidemiologia , Hipersensibilidade a Drogas/etiologia , Inibidores de beta-Lactamases/efeitos adversos , Adolescente , Adulto , Idoso , Anafilaxia/diagnóstico , Hipersensibilidade a Drogas/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Vigilância em Saúde Pública , Testes Cutâneos , Adulto JovemRESUMO
Genetically engineered mice and rats are increasingly used as models for exploring disease progression and mechanisms. The full spectrum of anatomic, biochemical, and functional changes that develop in novel, genetically engineered mouse and rat lines must be cataloged before predictions regarding the significance of the mutation may be extrapolated to diseases in other vertebrate species, including humans. A growing list of reference materials, including books, journal articles, and websites, has been produced in the last 2 decades to assist researchers in phenotyping newly engineered rodent lines. This compilation provides an extensive register of materials related to the pathology component of rodent phenotypic analysis. In this article, the authors annotate the resources they use most often, to allow for quick determination of their relevance to research projects.
Assuntos
Animais Geneticamente Modificados , Internet , Patologia , Fenótipo , Publicações , Roedores/genética , Animais , Feminino , Engenharia Genética , Genômica , Humanos , Masculino , Camundongos , Mutação , Ratos , Roedores/classificaçãoRESUMO
Neoplasia in both animals and humans results in part from lasting activation of tumor-promoting genes ("oncogenes") or diminished function of genes responsible for preventing neoplastic induction ("tumor suppressor genes"). The concept of "genetic addiction" has emerged to indicate that neoplastic cells cannot maintain a malignant phenotype without sustained genotypic abnormalities related to aberrant activity of oncogene(s) and/or inactivity of tumor suppressor gene(s). Interestingly, some genetic abnormalities reliably produce distinct morphologic patterns that can be used as structural signatures indicating the presence of a specific molecular alteration. Examples of such consistent genetic/microanatomic pairings have been identified for mutated oncogenes, such as rising mucin-producing capacity with RAS overexpression, and mutated tumor suppressor genes-including PTEN eliciting cell hypertrophy, RB1 dictating neuroendocrine differentiation, and TRP53 encouraging sarcomatous transformation. Familiarity with the concept of genetic addiction, as well as the ability to recognize such regular genomic-phenotypic relationships, are of paramount importance for comparative pathologists who are engaged in phenotyping genetically engineered mice to help unravel genomic intricacies in both health and disease.
Assuntos
Transformação Celular Neoplásica/genética , Regulação Neoplásica da Expressão Gênica/genética , Genótipo , Neoplasias/genética , Fenótipo , Animais , Modelos Animais de Doenças , Genes Supressores de Tumor , Engenharia Genética , Humanos , Camundongos , Camundongos Transgênicos , Mutação , Neoplasias/patologia , OncogenesRESUMO
The toxicity of diphenyl ditelluride (PhTe)2 is associated with its ability to oxidize sulfhydryl groups from biological molecules. Therefore, we evaluated possible molecular mechanisms of toxicity induced by this organochalcogen in Escherichia coli (E. coli) by evaluating oxidative damage markers, relative expression of genes associated with the cellular redox state in bacteria, such as katG, sodA, sodB, soxS, and oxyR, as well as the activity of enzymes responsible for cellular redox balance. After exposure of (PhTe)2 (6, 12, and 24 µg/mL), there was a decrease in non-protein thiols (NPSH) levels, an increase in protein carbonylation and lipid peroxidation in E. coli. Intra- and extracellular reactive species (RS) was increased at concentrations of 6, 12, and 24 µg/mL. The superoxide dismutase (SOD) activity was increased at the three concentrations tested, while catalase (CAT) activity was higher at 12 and 24 µg/mL. The soxS gene showed lower expression at the three concentrations tested, while the oxyR gene was supressed at 24 µg/mL. The katG antioxidant response gene showed lower expression, and sodA and sodB were positively activated, except for sodB at 6 µg/mL. Our findings demonstrate that exposure to (PhTe)2 induced RS formation, NPSH depletion and changes in transcriptional factors regulation, characterizing it as a multi-target compound, causing disruption in cellular oxidative state, as well as molecular mechanisms associated in E. coli.
Assuntos
Escherichia coli , Superóxido Dismutase , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Derivados de Benzeno , Catalase/genética , Catalase/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Compostos Organometálicos , Oxirredução , Estresse Oxidativo , Compostos de Sulfidrila/metabolismo , Superóxido Dismutase/metabolismo , Superóxido Dismutase-1/metabolismoRESUMO
In the postgenomic era, the accumulation of massive amounts of molecular and genetic data is quickly transforming the landscape of cancer research. A deeper understanding of cancer biology will allow pathologists studying genetically engineered mouse models and spontaneous tumors to ask novel questions and provide useful insights into disease mechanisms. Although tumor suppressor gene loss is known to be an essential step in the pathogenesis of many tumors, the variety of mechanisms that lead to such loss are poorly understood. This article provides an overview of loss of heterozygosity as an important mechanism of tumor suppressor gene loss; it also emphasizes the importance of loss of heterozygosity detection as a tool for tumor suppressor gene discovery. Understanding the applications of the array of molecular techniques currently available in cancer research will enable pathologists to further contribute to the advancement the field.
Assuntos
Perda de Heterozigosidade , Neoplasias/veterinária , Patologia Veterinária , Animais , Neoplasias/genética , Neoplasias/metabolismoRESUMO
INTRODUCTION: The diagnosis of renal function impairment and deterioration in congenital urinary tract obstruction (UTO) continues to be extremely challenging. The use of new renal biomarkers in this setting may favor early renal injury detection, allowing for a reliable choice of optimal therapeutic options and the prevention or minimization of definitive renal damage. OBJECTIVE: The aim of the study was to investigate a selection of promising biomarkers of renal injury with the intention of evaluating and comparing their profile with clinically based decisions for surgical intervention of infants with congenital obstructive uropathies. STUDY DESIGN: The first-year profile of renal biomarkers, serum creatinine (sCr), serum and urine cystatin C (CyC), neutrophil gelatinase-associated lipocalin (NGAL), kidney injury molecule-1 (KIM-1), transforming growth factor beta-1 (TGF-ß1), retinol-binding protein (RBP), and microalbuminuria (µALB), was analyzed in a cohort of 37 infants with congenital UTO, divided into three subgroups, 14 cases with grade III unilateral hydro(uretero)nephrosis, 13 cases with grade III bilateral hydro(uretero)nephrosis, and 10 cases with low urinary tract obstruction (LUTO), compared with 24 healthy infants matched by gestational age and birth weight. Serum and urine samples were stored at -70 °C and thereafter analyzed by quantitative enzymatic immunoassay. RESULTS: Compared with the control group (Figure), all renal biomarker values were significantly increased in patients (P ≤ 0.02). In the unilateral hydronephrosis and LUTO group, RBP (P ≤ 0.043), NGAL (P ≤ 0.043), KIM-1 (P ≤ 0.03), and TGF-ß1 (P ≤ 0.034) values dropped significantly after surgery. Neutrophil gelatinase-associated lipocalin alone and in combination with urine and serum CyC demonstrated the best performance in determining the need for surgery (area under the curve, 0.801 and 0.881, respectively). Biomarker profile analysis was suggestive of surgical intervention in 55.4% (7/13) of non-operated cases, and most of the biomarker values were above the cutoff levels within at least 3 months before the clinically based surgical decision in 58% (14/24) of all operated patients. DISCUSSION: To the best of the authors' knowledge, this is the first study to present the clinical use of selected group of serum and urinary biomarkers in the setting of UTO to distinguish between patients who would benefit from surgery intervention. The most promising results were obtained using NGAL, RBP, TGF-ß1, and KIM-1, especially in the unilateral hydro(uretero)nephrosis and LUTO subgroups when compared with the control group. CONCLUSIONS: Urine biomarkers, alone and in combination, demonstrated high potential as a non-invasive diagnostic tool for identifying infants who may benefit from earlier surgical intervention.
Assuntos
Tomada de Decisão Clínica , Obstrução Ureteral/metabolismo , Obstrução Ureteral/cirurgia , Obstrução Uretral/metabolismo , Obstrução Uretral/cirurgia , Obstrução do Colo da Bexiga Urinária/metabolismo , Obstrução do Colo da Bexiga Urinária/cirurgia , Biomarcadores/sangue , Feminino , Humanos , Lactente , Masculino , Valor Preditivo dos Testes , Obstrução Ureteral/congênito , Obstrução Uretral/congênito , Obstrução do Colo da Bexiga Urinária/congênito , Procedimentos Cirúrgicos UrológicosRESUMO
The decolouration of several azo dyes, commonly used in the leather industry, by crude laccase obtained from Trametes hirsuta cultivation was assessed. Among the six dyes studied four showed a decolouration percentage higher than 50% in 4h, whereas the other two showed more resistance to degradation. These results show the ability of laccase towards different dye structures as well as its enormous potential for the decolouration of recalcitrant azo dyes.
Assuntos
Compostos Azo/química , Compostos Azo/metabolismo , Corantes/química , Corantes/metabolismo , Lacase/metabolismo , Polyporales/enzimologia , Indústria Têxtil , Resíduos Industriais , Espectrofotometria , TemperaturaRESUMO
The present paper studies the decolourization of different synthetic dyes (Indigo Carmine, Bromophenol Blue, Methyl Orange and Poly R-478) by the white-rot fungus Trametes hirsuta at bioreactor scale under solid-state conditions, operating with ground orange peelings as a support-substrate. Dye decolourization was performed in both batch and continuous mode. Batch cultivation led to high decolourization percentages in a short time (100% for Indigo Carmine in 3h and 85% for Bromophenol Blue in 7 h). As for continuous cultivation, different hydraulic retention times (HRT) were studied (0.8, 1, 1.5 and 3d). The highest decolourization percentages were obtained operating at a HRT of 3d, especially for the dyes Methyl Orange and Poly R-478 (81.4% and 46.9%, respectively). This is a very interesting result, since there are few studies dealing with the continuous decolourization of dyes at bioreactor scale by fungal laccases.
Assuntos
Corantes/análise , Polyporales/crescimento & desenvolvimento , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Biodegradação Ambiental , Reatores Biológicos , Cor , Indústria TêxtilRESUMO
In this paper, the effect of redox mediators on synthetic acid dye decolourization (Sella Solid Red and Luganil Green) by laccase from Trametes hirsuta cultures has been investigated. All the redox mediators tested, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 1-hydroxybenzotriazole (HBT) and Remazol Brilliant Blue R (RBBR), led to higher activities than those obtained without mediators addition showing the suitability of the laccase/mediator system (LMS) in the decolourization of acid dyes. HBT was by far the most effective mediator, showing a decolourization percentage of 88% in 10 min for Sella Solid Red and of 49% in 20 min for Luganil Green. On the other hand, the stability of laccase against several metal ions, normally found in textile wastewater, was assessed. Laccase was stable at a concentration of 1mM for 7d against all the metal ions tested except for Zn+2, CrO4(-2), Cd+2, Cr2O7(-2), Fe+2, Cu+2 and especially Hg+2. When the concentration was increased to 10mM laccase stability decreased against all the metals assayed, in particular against Fe+2. In addition, the effect of metal ions on the decolourization process was also studied. It was found that Hg+2 inhibited the dye decolourization process, being the presence of HBT absolutely required for dye decolourization.
Assuntos
Corantes/química , Lacase/metabolismo , Metais/química , Eliminação de Resíduos Líquidos/métodos , Ácidos/química , Basidiomycota/enzimologia , Cor , Corantes/metabolismo , Íons , Lacase/química , Metais/farmacologia , Oxirredução , Indústria TêxtilRESUMO
Due to the numerous biotechnological applications of laccase enzyme, it is essential to know the influence of different agents usually present in the natural environment on its enzymatic action, especially for in situ treatment technologies. In the present work, a simple and rapid method to determine the inhibitory or inducer effect of different compounds on laccase activity was developed. The compounds tested were copper-chelating agents and heavy metals. It was found that using syringaldazine as a substrate, all copper-chelating agents (except EDTA) highly inhibited laccase activity (around 100%) at an inhibitor concentration lower than 20 mM. Moreover, 40% of inhibition, which was detected at a concentration of 20 mM for both Cd(2+) and Cu(2+) increased with concentration until nearly complete inhibition at 80 mM.
Assuntos
Basidiomycota/enzimologia , Quelantes/toxicidade , Lacase/antagonistas & inibidores , Metais Pesados/toxicidade , Testes de Toxicidade/métodos , Ácido Cítrico/toxicidade , Ácido Edético/toxicidade , Hidrazonas/metabolismo , Hidroxilamina/toxicidade , Cinética , Lacase/metabolismo , Malonatos/toxicidade , Ácido Oxálico/toxicidade , Ácidos Sulfônicos/toxicidadeRESUMO
Recent discoveries suggest that the critical events leading to the anti-proliferative activity of the IMiD immunomodulatory agents lenalidomide and pomalidomide in multiple myeloma (MM) cells are initiated by Cereblon-dependent ubiquitination and proteasomal degradation of substrate proteins Ikaros (IKZF1) and Aiolos (IKZF3). By performing kinetic analyses, we found that the downregulation or proteasomal degradation of Ikaros and Aiolos led to specific and sequential downregulation of c-Myc followed by IRF4 and subsequent growth inhibition and apoptosis. Notably, to ensure growth inhibition and cell death, sustained downregulation of Ikaros and Aiolos, c-Myc or IRF4 expression was required. In addition, we found that the half-maximal rate, rather than the final extent of Ikaros and Aiolos degradation, correlated to the relative efficacy of growth inhibition by lenalidomide or pomalidomide. Finally, we observed that all four transcription factors were elevated in primary MM samples compared with normal plasma cells. Taken together, our results suggest a functional link between Ikaros and Aiolos, and the pathological dysregulation of c-Myc and IRF4, and provide a new mechanistic understanding of the relative efficacy of lenalidomide and pomalidomide based on the kinetics of substrate degradation and downregulation of their downstream targets.
Assuntos
Antineoplásicos/farmacologia , Fator de Transcrição Ikaros/metabolismo , Fatores Reguladores de Interferon/metabolismo , Mieloma Múltiplo/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/fisiologia , Regulação para Baixo , Citometria de Fluxo , Técnicas de Silenciamento de Genes , Humanos , Immunoblotting , Imuno-Histoquímica , Lenalidomida , Mieloma Múltiplo/patologia , RNA Interferente Pequeno , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Talidomida/análogos & derivados , Talidomida/farmacologiaRESUMO
The development of resistance to therapy is unavoidable in the history of multiple myeloma patients. Therefore, the study of its characteristics and mechanisms is critical in the search for novel therapeutic approaches to overcome it. This effort is hampered by the absence of appropriate preclinical models, especially those mimicking acquired resistance. Here we present an in vivo model of acquired resistance based on the continuous treatment of mice bearing subcutaneous MM1S plasmacytomas. Xenografts acquired resistance to two generations of immunomodulatory drugs (IMiDs; lenalidomide and pomalidomide) in combination with dexamethasone, that was reversible after a wash-out period. Furthermore, lenalidomide-dexamethasone (LD) or pomalidomide-dexamethasone (PD) did not display cross-resistance, which could be due to the differential requirements of the key target Cereblon and its substrates Aiolos and Ikaros observed in cells resistant to each combination. Differential gene expression profiles of LD and PD could also explain the absence of cross-resistance. Onset of resistance to both combinations was accompanied by upregulation of the mitogen-activated protein kinase/extracellular signal-regulated kinase (ERK) kinase (MEK)/ERK pathway and addition of selumetinib, a small-molecule MEK inhibitor, could resensitize resistant cells. Our results provide insights into the mechanisms of acquired resistance to LD and PD combinations and offer possible therapeutic approaches to addressing IMiD resistance in the clinic.
Assuntos
Antineoplásicos/farmacologia , Dexametasona/farmacologia , Regulação Neoplásica da Expressão Gênica , Plasmocitoma/tratamento farmacológico , Talidomida/análogos & derivados , Proteínas Adaptadoras de Transdução de Sinal , Animais , Apoptose/efeitos dos fármacos , Benzimidazóis/farmacologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Quimioterapia Combinada , MAP Quinases Reguladas por Sinal Extracelular/genética , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Fator de Transcrição Ikaros/genética , Fator de Transcrição Ikaros/metabolismo , Lenalidomida , Camundongos , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/genética , Mieloma Múltiplo/metabolismo , Mieloma Múltiplo/patologia , Transplante de Neoplasias , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Plasmocitoma/genética , Plasmocitoma/metabolismo , Plasmocitoma/patologia , Transdução de Sinais , Talidomida/farmacologia , Transativadores/genética , Transativadores/metabolismoRESUMO
An adult, wild-caught, female prairie falcon (Falco mexicanus) was presented with the chief complaint of anorexia. Radiographic findings included increased densities within the air sacs, and coelomic endoscopy revealed numerous slender worms within the air sacs and on the serosal surfaces of the ovary, oviduct, liver, proventriculus, and ventriculus. The bird seemed to improve for a short period of time with antiparasitic therapy (ivermectin and fenbendazole) and supportive care. Twenty-one days after initial presentation, the bird became recumbent with increasing pelvic limb neurologic deficits and was euthanized. On histopathologic examination, mature nematodes and larvated eggs identified as Serratospiculoides amaculata were found within the subdural space of the distal thoracolumbar and synsacral spinal cord and within the coelomic cavity. This case suggests that S. amaculata can cause clinically significant lesions in its falconiform host with potentially fatal results.
Assuntos
Doenças das Aves/parasitologia , Mielite/veterinária , Infecções por Nematoides/veterinária , Aves Predatórias/parasitologia , Animais , Anorexia/complicações , Anorexia/parasitologia , Anorexia/veterinária , Eutanásia/veterinária , Feminino , Interações Hospedeiro-Parasita , Mielite/complicações , Mielite/parasitologia , Nematoides/fisiologia , Infecções por Nematoides/complicações , Infecções por Nematoides/patologia , Região SacrococcígeaRESUMO
Laccase production by the white-rot fungus Trametes versicolor (CBS100.29) grown in submerged cultures was studied. Addition of different insoluble lignocellulosic materials into the culture medium in order to enhance laccase production was investigated. The lignocellulosic materials were grape seeds, grape stalks and barley bran, selected because of their availability and low cost, since they are agro-industrial wastes abundant in most countries. Barley bran gave the highest activities, a maximum value of 639U/l, which was 10 times the value attained in the cultures without lignocellulosics addition. The decolourisation of a model dye, Phenol Red, by the ligninolytic fluids obtained in the above-mentioned cultures was investigated. Grape stalk and barley bran cultures showed the highest ability to decolourise the dye, attaining a percentage of decolourisation of around 60% in 72 h.
Assuntos
Oxirredutases/metabolismo , Basidiomycota/enzimologia , Biodegradação Ambiental , Biotecnologia , Corantes/farmacologia , Hordeum , Resíduos Industriais , Lacase , Fenolsulfonaftaleína/farmacologia , Fatores de TempoRESUMO
Alginate beads, polyurethane foam, nylon sponge and stainless steel sponge were tested as carrier materials for the white-rot fungus Trametes hirsuta for laccase production under submerged fermentation conditions. Stainless steel sponge was the best carrier material leading to the highest laccase activities of up to 800 U/l after 8 days of cultivation. These values are higher than those reported to date operating with inert supports and without inducer addition. In a 1-l bioreactor containing T. hirsuta immobilised on stainless steel sponge laccase activities of about 2200 U/l were obtained when the culture medium was supplemented with 1 mM copper sulphate. There were no operational problems with this system during culturing time. The textile dye Indigo Carmine was almost totally degraded in 3 days by T. hirsuta grown in this bioreactor, while Lanaset Marine was degraded in two successive batches, reaching in the first batch a decolourization percentage of about 82% in 15 h and in the second one by 71% in 28 h. Results obtained after inhibition of growth of T. hirsuta by antibiotics indicated that dye decolourization could not exclusively be attributed to laccase activity.
Assuntos
Biotecnologia/métodos , Corantes/química , Polyporales/metabolismo , Aço Inoxidável , Têxteis , Eliminação de Resíduos Líquidos/métodos , Reatores Biológicos , Biotecnologia/instrumentação , Células Imobilizadas , Corantes/metabolismo , Lacase/metabolismoRESUMO
This work reports a preliminary design of a new photochemical reactor and its application to photochemical degradation of two dyes, Crystal Violet and Azure B, operating in both batch and continuous processes. A novel kind of photocatalyst, consisting of ZnO immobilised in alginate gel beads, which is able to photodegrade organic dyes effectively, has been employed in the present study. When this photocatalyst, at a concentration of 1 g of ZnO per litre of alginate gel at 3%, was employed in batch process, almost total decolourisation of Crystal Violet in reaction times lower than 120 min was observed. Operating in continuous process at different residence times, it was possible to achieve a total decolourisation of both Crystal Violet and Azure B. Moreover, the total organic carbon content (TOC) was reduced to 90% in the former and to 52% in the latter. These results indicated that the photoreactor developed in the present work was able to degrade effectively dyes of different structures, revealing the non-specificity of the system.
Assuntos
Corantes/química , Resíduos Industriais/análise , Fotólise/efeitos da radiação , Eliminação de Resíduos Líquidos/métodos , Alginatos , Corantes Azur/química , Corantes Azur/isolamento & purificação , Corantes Azur/efeitos da radiação , Reatores Biológicos , Carbono/metabolismo , Corantes/isolamento & purificação , Corantes/efeitos da radiação , Violeta Genciana/química , Violeta Genciana/isolamento & purificação , Violeta Genciana/efeitos da radiação , Ácido Glucurônico , Ácidos Hexurônicos , Cinética , Fotólise/efeitos dos fármacos , Espectrofotometria , Água/química , Óxido de Zinco/administração & dosagemRESUMO
The production of ligninolytic enzymes by the fungus Phanerochaete chrysosporium in a fixed-bed tubular bioreactor, filled with cubes of nylon sponge, operating in semi-solid-state conditions, was studied. Maximum individual manganese-dependent peroxidase (MnP) and lignin peroxidase (LiP) activities of 1293 and 225 U/l were detected. The in vitro decolourisation of two structurally different dyes (Poly R-478, crystal violet) by the extracellular liquid obtained in the above-mentioned bioreactor was monitored in order to determine its degrading capability. The concentration of some compounds (sodium malonate, manganese sulphate) from the reaction mixture was optimised in order to maximise the decolourisation levels. A percentage of Poly R-478 decolourisation of 24% after 15 min of dye incubation was achieved. On the other hand, a methodology for a long treatment of these dyes based on the continuous addition of MnP enzyme and H(2)O(2) was developed. Moreover, this enzymatic treatment was compared with a photochemical decolourisation process. The former allowed to maintain the degradation rate almost constant for a long time, resulting in a decolourisation percentage of 70% and 30% for crystal violet and Poly R-478, respectively, after 2 h of treatment. As for the latter, it was not able to degrade Poly R-478, whereas crystal violet reached a degradation of 40% in 2 h.
Assuntos
Antraquinonas/metabolismo , Anti-Infecciosos Locais/metabolismo , Reatores Biológicos , Corantes/metabolismo , Violeta Genciana/metabolismo , Phanerochaete/fisiologia , Polímeros/metabolismo , Poluentes Químicos da Água/metabolismo , FotoquímicaRESUMO
A 6-month-old Morgan colt was evaluated because of a 10-cm right-sided retropharyngeal swelling. The swelling was soft and moveable on examination, and palpation did not elicit signs of pain. Radiography revealed a large space-occupying mass ventral to the second cervical vertebra; ultrasonography revealed an anechoic fluid-filled structure with a well-defined hyperechoic capsule. Fine-needle aspiration yielded a viscous amber fluid. Cytologic evaluation indicated that the fluid was an exudate; anaerobic and aerobic bacterial culture did not yield any growth. Histologic examination of a portion of the cyst capsule revealed a connective tissue wall lined by pseudostratified columnar to cuboidal epithelium, consistent with a branchial cyst. The cyst wall was marsupialized to the skin, and iodine sclerotherapy was performed twice daily for 14 days, at which time forceps were introduced into the cyst and the cyst lining was removed. The site was allowed to heal by second intention, but 10 days later, the swelling recurred. An incision was made over the previous marsupialization site, and residual remnants of the cauterized cyst lining were removed with a forceps. The foal did not have any other complications during the subsequent 2 years. Branchial arch cysts are uncommon embryonic anomalies of horses, mice, cats, dogs, and cattle. Results suggest that marsupialization and iodine sclerotherapy may be a viable alternative to surgical excision in horses with branchial cysts; however, the entire cyst lining must be removed at the completion of sclerotherapy to prevent recurrence and abscess formation.
Assuntos
Branquioma/veterinária , Neoplasias de Cabeça e Pescoço/veterinária , Doenças dos Cavalos/terapia , Recidiva Local de Neoplasia/veterinária , Escleroterapia/veterinária , Animais , Branquioma/diagnóstico , Branquioma/cirurgia , Branquioma/terapia , Neoplasias de Cabeça e Pescoço/diagnóstico , Neoplasias de Cabeça e Pescoço/cirurgia , Neoplasias de Cabeça e Pescoço/terapia , Doenças dos Cavalos/diagnóstico , Doenças dos Cavalos/cirurgia , Cavalos , Iodo , Masculino , Recidiva Local de Neoplasia/diagnóstico por imagem , Recidiva Local de Neoplasia/cirurgia , UltrassonografiaRESUMO
The production of manganese-dependent peroxidase (MnP) by Phanerochaete chrysosporium in a new solid-state bioreactor, the immersion bioreactor, operating with lignocellulosic waste, such as wood shavings, was investigated. Maximum MnP and lignin peroxidase (LiP) activity of 13.4 and 8.48 mukat/L were obtained, respectively. The in vitro decolorization of several synthetic dyes by the extracellular liquid produced in the above-mentioned bioreactor (containing mainly MnP) was carried out and its degrading ability was assessed. The highest decolorization was reached with Indigo Carmine (98%) followed by Bromophenol Blue (56%) and Methyl Orange (36%), whereas Gentian Violet was hardly decolorized (6%).