RESUMO
The development of new cost-effective bioprocesses for the production of cellulolytic enzymes is needed in order to ensure that the conversion of biomass becomes economically viable. The aim of this study was to determine whether a novel sequential solid-state and submerged fermentation method (SF) could be validated for different strains of the Trichoderma genus. Cultivation of the Trichoderma reesei Rut-C30 reference strain under SF using sugarcane bagasse as substrate was shown to be favorable for endoglucanase (EGase) production, resulting in up to 4.2-fold improvement compared with conventional submerged fermentation. Characterization of the enzymes in terms of the optimum pH and temperature for EGase activity and comparison of the hydrolysis profiles obtained using a synthetic substrate did not reveal any qualitative differences among the different cultivation conditions investigated. However, the thermostability of the EGase was influenced by the type of carbon source and cultivation system. All three strains of Trichoderma tested (T. reesei Rut-C30, Trichoderma harzianum, and Trichoderma sp INPA 666) achieved higher enzymatic productivity when cultivated under SF, hence validating the proposed SF method for use with different Trichoderma strains. The results suggest that this bioprocess configuration is a very promising development for the cellulosic biofuels industry.
Assuntos
Biotecnologia/métodos , Enzimas/biossíntese , Trichoderma/enzimologia , Celulase/metabolismo , Celulose/metabolismo , Ativação Enzimática , Estabilidade Enzimática , Fermentação , Meia-Vida , Concentração de Íons de Hidrogênio , Hidrólise , Reprodutibilidade dos Testes , Saccharum/química , TemperaturaRESUMO
AIM: To evaluate the influence of reciprocating single-file instrumentation with different working lengths (WL) and apical preparation sizes on apical bacterial extrusion. METHODOLOGY: Sixty-eight human single-rooted pre-molars were used. Conventional access cavities were prepared, and the root canals were contaminated with an Enterococcus faecalis suspension and incubated at 37°C for 30 days. Teeth were then divided into four groups of 15 specimens each (Reciproc size 25, .08 taper and Reciproc size 40, .06 taper instruments were used at the foramen; Reciproc size 25, .08 taper and Reciproc size 40, .06 taper instruments were used 1 mm short of the foramen). Positive and negative controls consisted of four infected and four uninfected pre-molars that were instrumented according to each experimental group. Bacteria extruded from the apical foramen during instrumentation were collected into vials containing 0.9% NaCl. The microbiological samples were then incubated in a brain-heart agar medium for 24 h. The resulting bacterial titre, in colony-forming units (CFU) per mL, was determined, and these data were analysed using a Wilcoxon matched-pairs signed rank test and a Kruskal-Wallis H-test. The level of significance was set at α = 0.05. RESULTS: No growth was observed in the negative control group. All positive controls demonstrated bacterial growth after the experimental time interval. No significant difference was found in the number of CFU amongst all experimental groups (P = 0.95). CONCLUSIONS: This study showed that the WL and the apical preparation size did not have a significant effect on bacterial extrusion when performing reciprocating instrumentation.
Assuntos
Instrumentos Odontológicos , Cavidade Pulpar/microbiologia , Preparo de Canal Radicular/instrumentação , Ápice Dentário/microbiologia , Dente Pré-Molar , Contagem de Colônia Microbiana , Equipamentos Odontológicos de Alta Rotação , Enterococcus faecalis , Desenho de Equipamento , Humanos , Técnicas In Vitro , Irrigantes do Canal Radicular/uso terapêuticoRESUMO
Sequential solid-state and submerged cultivation with sugarcane bagasse as substrate for cellulase production by Aspergillus niger A12 was assessed by measuring endoglucanase activity. An unconventional pre-culture with an initial fungal growth phase under solid-state cultivation was followed by a transition to submerged fermentation by adding the liquid culture medium to the mycelium grown on solid substrate. For comparison, control experiments were conducted using conventional submerged cultivation. The cultures were carried out in shake flasks and in a 5-L bubble column bioreactor. An endoglucanase productivity of 57 ± 13 IU/L/h was achieved in bubble column cultivations prepared using the new method, representing an approximately 3-fold improvement compared to conventional submerged fermentation. Therefore, the methodology proposed here of a sequential fermentation process offers a promising alternative for cellulase production.
Assuntos
Aspergillus niger/enzimologia , Aspergillus niger/crescimento & desenvolvimento , Técnicas de Cultura de Células/métodos , Celulase/biossíntese , Celulose/farmacologia , Saccharum/química , Aspergillus niger/efeitos dos fármacos , Reatores Biológicos/microbiologia , Endo-1,4-beta-Xilanases/metabolismo , Fermentação/efeitos dos fármacos , Fatores de TempoRESUMO
ABSTRACT Histological characteristics of the alimentary canal of termite workers and pseudo-workers are generally used for systematics and phylogeny studies. Research has confirmed the value of the workers spiral digestive tract model and its morphology for the systematics of higher termites, mainly in Termitidae. Thus, the present study was carried out describing the alimentary canal of Nasutitermes coxipoensis workers through light microscopy. Workers of N. coxipoensis were immobilized at low temperature (-4º C) for the extraction the alimentary canal, which was fixed in Bouin liquid for 24h, embedded in paraplast, the slices being stained by hematoxilin-eosin (H-E) and Mallorys trichrome stain. Overall, the histological characteristics found for the alimentary canal of N. coxipoensis were consistent with those described in several species of termites, endorsing the method applied. However, this study found differences in the morphology of epithelial cells and on the types of epithelial folds in the region of the stomodeum regarding the arrangement and number of nests, as well as the presence of peritrophic membrane in the mesenterum region. Therefore, these characteristics may be used as criteria for the differentiation of species among termites of the genus Nasutitermes.
RESUMO Em Isoptera as características do tubo digestivo dos operários e pseudo-operários são normalmente utilizadas em sistemática e filogenia. Pesquisas têm confirmado o valor do modelo espiral e morfologia do tubo digestivo dos operários para a sistemática em cupins superiores, principalmente na família Termitidae. Assim, este trabalho objetivou descrever a histologia do canal alimentar de operários de Nasutitermes coxipoensis (Holmgren) por meio da microscopia de luz, visando obter informações que contribuam para a sistemática desse gênero. Operários de N. coxipoensis foram imobilizados a baixa temperatura (-4o C) para a retirada do canal alimentar, o qual foi fixado em Boüin aquoso por 24h, incluído em paraplast, e os cortes corados pela Hematoxilina-Eosina (H-E) e Tricrômico de Mallory. Em geral, as características histológicas encontradas para o canal alimentar de operários de N. coxipoensis foram consistentes com aquelas observadas em várias espécies de cupins validando o método usado. No entanto, foram evidenciadas diferenças na morfologia das células epiteliais e tipos de dobras do epitélio na região do estomodeu, na disposição e número dos ninhos, bem como a presença da membrana peritrófica na região do mesêntero. Portanto, essas características podem ser utilizadas como critérios auxiliares para a diferenciação de espécies entre cupins do gênero Nasutitermes.
RESUMO
ABSTRACT Investigations concerning pathogenicity require basic knowledge in the biology and ecology of the target species involved in the study. The present work describes a technique to maintain the termite Nasutitermes coxipoensis under laboratory conditions to conduct tests with entomopathogenic fungi. The termites were maintained in plastic boxes with a piece of the original nest (20 g) and different food substrates: rotting wood, dry wood, sugarcane pulp, and wood paper. The survival function S(t) was applied to determine the best substrate for maintaining the termites under laboratory conditions, considering an ending time for the experiment of 18 days (t). The results indicated the sugarcane pulp, followed by wood paper as the best substrates for maintaining N. coxipoensis. This information will open opportunities for studies with termites under laboratory conditions.
RESUMO Pesquisas sobre patogenicidade necessitam de conhecimentos básicos em biologia e ecologia dos organismos envolvidos no estudo. O presente trabalho descreve uma técnica de manutenção do cupim Nasutitermes coxipoensis em condições de laboratório a fim de realização de testes com fungos entomopatogênicos. Os cupins foram mantidos em caixas plásticas contendo pedaço de ninho (20 g) e substratos alimentares diferentes: madeira em decomposição, madeira seca, colmo de cana-de-açúcar e papel madeira. Utilizou-se a função de sobrevivência S(t) com o objetivo de verificar a probabilidade de vida dos insetos até um tempo t (18 dias), a fim de mantê-los em condições de laboratório. Os resultados indicaram que o substrato que possibilitou maior tempo de sobrevivência foi cana-de-açúcar, seguido de papel madeira picado. Tais informações possibilitarão a realização de testes diversos com cupins, em condições de laboratório.
RESUMO
The present research describes the histology of the midgut, gastric caeca, and pyloric valve of Tropidacris collaris (Stoll, 1813), (Orthopetera: Romaleidae). We used light microscopy, staining (Gomori's trichrome and periodic acid-Schiff (PAS)), and a routine histological analysis method (hematoxilin-eosin). The insects were obtained from, and also bred in, the Laboratory of Entomology, Department of Biology, of the Rural Federal University of Pernambuco (UFRPE). The collected material was fixed in alcoholic Boüin and embedded in paraplast. The results demonstrated that the midgut wall is composed of an inner epithelial layer and two outer layers of striate muscles: one internal (circular) and the other external (longitudinal), with connective tissue between the muscle fibers. The epithelium is single-layered, with two cell types: regenerative and elongated columnar. The gastric caeca presents muscle layers similar to those of the midgut. Simple columnar epithelium lines the gastric caeca, which presents villi and projects towards the lumen. The pyloric valve is of striate muscle tissue, covered by a single epithelial-cell layer.
A presente pesquisa teve como objetivo descrever a histologia do mesêntero, cecos gástricos e válvula pilórica de Tropidacris collaris (Stoll, 1813) (Orthoptera: Romaleidae), por meio da microscopia de luz, utilizando-se colorações especiais (Tricrômico de Gomori e P.A.S. - Acido periódico de Schiff) e de rotina (Hematoxilina-Eosina). Os insetos foram obtidos da criação existente no Laboratório de Entomologia, do Departamento de Biologia, da UFRPE. O material coletado foi fixado em Boüin alcoólico e processado para inclusão em "paralast". Os resultados mostraram que a parede do mesêntero é constituída por duas camadas de músculo estriado: uma interna (circular) e outra externa (longitudinal), com a presença de tecido conjuntivo entre as fibras musculares. O epitélio é do tipo simples, constituído por dois tipos de células: células regenerativas e células colunares altas. Os cecos gástricos também apresentam as camadas de músculo semelhantes às observadas no mesêntero. O tecido epitelial é do tipo simples colunar projetando-se para a luz do órgão, formando vilosidades. A válvula pilórica é constituída por tecido muscular estriado, recoberto por tecido epitelial.
Assuntos
Animais , Gafanhotos/anatomia & histologia , Mesentério/anatomia & histologia , Estômago/anatomia & histologia , Gafanhotos/citologia , Mesentério/citologia , Estômago/citologiaRESUMO
Recent findings from our laboratory suggest that intracellular peptides containing putative post-translational modification sites (i.e., phosphorylation) could regulate specific protein interactions. Here, we extend our previous observations showing that peptide phosphorylation changes the kinetic parameters of structurally related endopeptidase EP24.15 (EC 3.4.24.15), neurolysin (EC 3.4.24.16), and angiotensin-converting enzyme (EC 3.4.15.1). Phosphorylation of peptides that are degraded by these enzymes leads to reduced degradation, whereas phosphorylation of peptides that interacted as competitive inhibitors of these enzymes alters only the K(i)'s. These data suggest that substrate phosphorylation could be one of the mechanisms whereby some intracellular peptides would escape degradation and could be regulating protein interactions within cells.
Assuntos
Metaloendopeptidases/metabolismo , Peptidil Dipeptidase A/metabolismo , Sequência de Aminoácidos , Hidrólise , Dados de Sequência Molecular , Fosforilação , Especificidade por SubstratoRESUMO
The present research describes the histology of the midgut, gastric caeca, and pyloric valve of Tropidacris collaris (Stoll, 1813), (Orthopetera: Romaleidae). We used light microscopy, staining (Gomori's trichrome and periodic acid-Schiff (PAS)), and a routine histological analysis method (hematoxilin-eosin). The insects were obtained from, and also bred in, the Laboratory of Entomology, Department of Biology, of the Rural Federal University of Pernambuco (UFRPE). The collected material was fixed in alcoholic Botüin and embedded in paraplast. The results demonstrated that the midgut wall is composed of an inner epithelial layer and two outer layers of striate muscles: one internal (circular) and the other external (longitudinal), with connective tissue between the muscle fibers. The epithelium is single-layered, with two cell types: regenerative and elongated columnar. The gastric caeca presents muscle layers similar to those of the midgut. Simple columnar epithelium lines the gastric caeca, which presents villi and projects towards the lumen. The pyloric valve is of striate muscle tissue, covered by a single epithelial-cell layer.
Assuntos
Gafanhotos/anatomia & histologia , Mesentério/anatomia & histologia , Estômago/anatomia & histologia , Animais , Gafanhotos/citologia , Mesentério/citologia , Estômago/citologiaRESUMO
Recent findings from our laboratory suggest that intracellular peptides containing putative post-translational modification sites (i.e., phosphorylation) could regulate specific protein interactions. Here, we extend our previous observations showing that peptide phosphorylation changes the kinetic parameters of structurally related endopeptidase EP24.15 (EC 3.4.24.15), neurolysin (EC 3.4.24.16), and angiotensin-converting enzyme (EC 3.4.15.1). Phosphorylation of peptides that are degraded by these enzymes leads to reduced degradation, whereas phosphorylation of peptides that interacted as competitive inhibitors of these enzymes alters only the Ki's. These data suggest that substrate phosphorylation could be one of the mechanisms whereby some intracellular peptides would escape degradation and could be regulating protein interactions within cells.
Assuntos
Humanos , Fosforilação , Peptídeos/classificação , Complexo de Endopeptidases do ProteassomaRESUMO
This study evaluates further the anti-inflammatory and anti-allergic properties of polygodial, a sesquiterpene extracted from the barks plant Drymis winteri (Winteraceae). Polygodial (12.8-128.1 micromol/kg, i.p.) 30 min prior, inhibited significantly the mouse paw oedema induced by prostaglandin E2, bradykinin (BK) substance P (SP), dextran, platelet activating factor (PAF) or carrageenan. Polygodial also inhibited arachidonic acid-, capsaicin- and croton oil-induced ear oedema in mice. Polygodial (42.7 micromol/kg, i.p.), significantly inhibited both exudation and cell influx when assessed in the pleurisy induced by SP and histamine, and to a less extent the inflammatory response caused by carrageenan, PAF, BK and des-Arg9-BK. Finally, polygodial (4.2-42.7 micromol/kg, i.p.) produced dose-related inhibition of paw oedema induced by ovalbumin, protecting in a time-dependent manner the anaphylactic shock induced by endovenous administration of ovalbumin in animals which had been actively sensitised by this antigen. These and our previous results indicate that the major component present in the bark of the plant D. winteri, the sesquiterpene polygodial exerts an interesting anti-inflammatory and anti-allergic properties when assessed in rats and mice.
Assuntos
Antialérgicos/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Sesquiterpenos/uso terapêutico , Anafilaxia/etiologia , Anafilaxia/prevenção & controle , Animais , Carragenina/efeitos adversos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Edema/induzido quimicamente , Edema/tratamento farmacológico , Feminino , Membro Posterior/efeitos dos fármacos , Membro Posterior/patologia , Mediadores da Inflamação/efeitos adversos , Mediadores da Inflamação/antagonistas & inibidores , Masculino , Camundongos , Ovalbumina/efeitos adversos , Ovalbumina/imunologia , Pleurisia/induzido quimicamente , Pleurisia/tratamento farmacológico , Ratos , Ratos WistarRESUMO
We report on the preliminary clinical and electrophysiological aspects of an in-patient possibly presenting epilepsia partialis continua (Koshevnikov). We discuss the different etiologies and emphasize on the possible idiopathic form in this case.
Assuntos
Epilepsia Parcial Contínua/diagnóstico , Adulto , Epilepsia Parcial Contínua/etiologia , Epilepsia Parcial Contínua/fisiopatologia , Feminino , HumanosRESUMO
OBJECTIVES: To study the effectiveness of thymectomy (TY) in a group of patients with myasthenia gravis compared to a group of patients submitted to conservative treatment (CT) at a similar clinical stage. METHODS: Among 153 patients with myasthenia gravis, we paired 28 patients who underwent TY, with 28 cases under CT. The following data were analyzed: gender, age, and age at the beginning of symptoms, illness duration, follow-up time and type of medical treatment. There was no statistical difference between these 2 groups. The mean time for TY was 2.5 (0.2-13) years after the onset of the disease. The cases were evaluated through a functional scale at the beginning and at the end of the study. RESULTS: We found complete remission in 15 cases (TY 6, CT 9), improved (normal life with or without minimal symptoms and with or without medication) 9 cases (TY 8, CT 1), improved with partial control and minimal limitation 32 cases (TY 14, CT 18), and poor control 2 cases (TY 2). No death was found in this group. CONCLUSION: There was no statistical difference between the conservative treatment and thymectomy groups, regarding remission or improvement. Furthermore TY done in the first year of the disease or latter, did not change the final outcome.
Assuntos
Miastenia Gravis/cirurgia , Timectomia , Adolescente , Adulto , Criança , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Miastenia Gravis/diagnóstico , Exame Neurológico , Estudos Retrospectivos , Resultado do TratamentoRESUMO
We have retrospectively analysed the records of patients diagnosed as having myasthenia gravis and followed up in our department from February 1973 to March 1995. The main clinical findings were ptosis, diplopia, dysphagia, dysphonia or dysarthria, mastigatory impairment, dyspnea, asthenia, weakness of the cervical muscles and of the extremities, as well as findings of the physical and neurological examination. Based on the information collected, the patients were classified clinically according the modified Osserman-Gerkins scale, but considering the non-dynamic aspects of that scale, we used the modified functional scale of Niakan and classified the patients clinically as follows: remission, controlled, stable, partially controlled, poorly controlled, no response. We collected 153 patients, 104 (68.0%) females and 49 (32.0%) males producing a female/male ratio of 2.2:1. The duration of the disease varied from seven days to 27 years, mean 6.26 years (+/- 5.44). Age at the first symptoms varied between 24 hours to 80 years, mean of 32.13 years (+/- 19.48). We had 30 patients ranging from 0 to 15 years of age, 91 patients were observed between 15 and 50 years and 32 patients after the age of 50 years. Above the age of 60 years, the disease aflicts males more than females with a ratio of 1.5:1. The acquired autoimmune form with generalized weakness was the most frequent presentation. However, ocular muscle weakness with ptosis and diplopia were the most common clinical presentation in our series.
Assuntos
Miastenia Gravis/fisiopatologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Miastenia Gravis/epidemiologia , Estudos RetrospectivosRESUMO
We studied historical aspects of myasthenia gravis starting from its first description by the English physician, Sir Thomas Willis, in 1672. We also describe the difficulties in managing treating the first diagnosed patient. Historical facts related to the investigation and the initial treatment of this disorder as well as curiosities seldom mentioned in the literature are part of this paper.
Assuntos
Miastenia Gravis/história , História do Século XVII , História do Século XVIII , História do Século XIX , História do Século XX , HumanosRESUMO
We describe two cases of infantile neuroaxonal dystrophy, which is a rare, neurodegenerative disease, with autosomal recessive inheritance. The first case was an 8 year old boy, with arrested motor and mental development, ataxia and muscle weakness. On physical examination there was horizontal and vertical nystagmus, optic disc atrophy, hypotonia; deep tendon reflexes were absent. The second case was a 1.6 year old boy with arrested motor and mental development, and seizures. On physical examination there was optic atrophy, hypertonia and hyperreflexia. Both patients had on sural nerve biopsy neuronal enlargement, consistent with neuroaxonal dystrophy. Diagnosis without pathological confirmation with neuroaxonal spheroids is very difficult, because the clinical picture is variable and the neurophysiological findings are non specific.
Assuntos
Distrofias Neuroaxonais/patologia , Biópsia , Criança , Eletroencefalografia , Humanos , Lactente , Masculino , Nervo Sural/patologia , Tomografia Computadorizada por Raios XRESUMO
We report on the clinical characteristics of amyotrophic lateral sclerosis (ALS) in Fortaleza (Northeastern Brazil). For this, we analyzed retrospectively (from 1980 to 1999) 78 cases of ALS from the Service of Neurology of the University Hospital of Fortaleza diagnosed clinically and laboratorially (EMG, muscle biopsy, myelography, blood biochemistry, muscle enzymes and cranio-cervical X-ray). The results showed that they were mostly sporadic ALS (76/78), and they were divided into definite (n = 36), probable (n = 20), possible (n = 15) and suspected (n = 7), according to the level of diagnostic certainty. They were also subdivided into juvenile (n = 17), early-onset adult (n = 18), age-specific (n = 39) and late-onset (n = 4) groups. Clinically, they presented as initials symptoms, principally, asymmetrical (30/78) and symmetrical (24/78) weakness of extremities, besides bulbar signs, fasciculations, and atrophy. Curiously, pain as first symptom occurred in an expressive fashion (17/78). The predominant initial anatomic site, in this series, was the spinal cord, and mainly affecting the arms. As to the symptom accrual from region to region, this occurs more quickly in contiguous areas, and fasciculations are predominant when bulbar region was associated.
Assuntos
Esclerose Lateral Amiotrófica/diagnóstico , Adolescente , Adulto , Idoso , Esclerose Lateral Amiotrófica/classificação , Esclerose Lateral Amiotrófica/fisiopatologia , Brasil , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
We report two cases of Kennedy's disease (muscle weakness, amyotrophy, intentional tremor, endocrine abnormalities, and denervation signs at electromyography). This entity must be differentiated from other motor neuron disorders by the genetic pattern (X-liked recessive), gynecomastia, testicular atrophy, oligospermia and good prognosis. A discussion about the clinical pattern and evolution is made.
Assuntos
Atrofia Muscular Espinal/diagnóstico , Adolescente , Adulto , Diagnóstico Diferencial , Humanos , Masculino , Atrofia Muscular Espinal/genética , Linhagem , Prognóstico , SíndromeRESUMO
A type-specific serological survey among 1042 random nonneurological outpatients in two cities in the state of Ceara (northeastern Brazil) shows a low prevalence of HTLV-I (0.34% in Fortaleza; 0.44% in Crato) and of HTLV-II (0.34% in Fortaleza; 0% in Crato). Among 62 chronic myelopathic patients seen in Fortaleza 27 patients were found with clinical features of tropical spastic paraparesis (TSP); 10 of 27 were found HTLV-I seropositive (37%; 95% confidence limits, 19-58%). Proviral genome detection by polymerase chain reaction in 5 seropositive and 12 seronegative patients confirmed the serological findings. This excludes HTLV-I or -II infection as a cause in the seronegative TSP patients. The HTLV-positive and -negative patients did not differ clinically and by history, except that seropositives had a longer mean disease duration, a female predominance, and a higher proportion of white Caucasians. In this population with low HTLV-I and HTLV-II prevalences, HTLV-negative TSP is at least as frequent as the HTLV-I-associated TSP.
Assuntos
Vírus Linfotrópico T Tipo 1 Humano/isolamento & purificação , Vírus Linfotrópico T Tipo 2 Humano/isolamento & purificação , Paraparesia Espástica Tropical/virologia , Brasil/epidemiologia , Feminino , Humanos , Masculino , Paraparesia Espástica Tropical/epidemiologia , Paraparesia Espástica Tropical/etnologia , Prevalência , População BrancaAssuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Adulto , Idoso , Assistência Ambulatorial , Bleomicina/administração & dosagem , Cisplatino/administração & dosagem , Esquema de Medicação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos PilotoRESUMO
The authors have studied 270 Hansen's disease patients diagnosed and registered at the Neurologic and Dermatologic Sanitary Unit, in Crato, Ceará, from June, 1981 till August, 1983. This work presents an analysis of the aspects of the endemy, with percentual and absolute values and compares them with the consulted data. Finally the authors emphasize the disease's morbidity and characterize it as a serious and present problem of public health in Crato, Ceará.