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1.
An Bras Dermatol ; 2024 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-38493053

RESUMEN

Prurigo is a reactive, hyperplastic skin condition characterized by pruritic papules, plaques, and/or nodules. The temporal classification includes acute/subacute and chronic disease (≥ 6 weeks), with different clinical variants, synonymies, and underlying etiological factors. The immunology of chronic prurigo shows similarities with atopic dermatitis due to the involvement of IL-4 and IL-13, IL-22, and IL-31. Treatment includes antihistamines, topical steroids, dupilumab, and JAK inhibitors. Several conditions manifest clinically as prurigo-like lesions, and the correct clinical diagnosis must precede correct treatment. Furthermore, chronic prurigos represent a recalcitrant and distressing dermatosis, and at least 50% of these patients have atopic diathesis, the treatment of which may induce adverse effects, especially in the elderly. The quality of life is significantly compromised, and topical treatments are often unable to control symptoms and skin lesions. Systemic immunosuppressants, immunobiologicals, and JAK inhibitors, despite the cost and potential adverse effects, may be necessary to achieve clinical improvement and quality of life. This manuscript reviews the main types of prurigo, associated diseases, their immunological bases, diagnosis, and treatment.

3.
An Bras Dermatol ; 98(6): 814-836, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37302894

RESUMEN

This publication is an update of the "Consensus on the therapeutic management of atopic dermatitis - Brazilian Society of Dermatology" published in 2019, considering the novel, targeted-oriented systemic therapies for atopic dermatitis. The initial recommendations of the current consensus for systemic treatment of patients with atopic dermatitis were based on a recent review of scientific published data and a consensus was reached after voting. The Brazilian Society of Dermatology invited 31 experts from all regions of Brazil and 2 international experts on atopic dermatitis who fully contributed to the process. The methods included an e-Delphi study to avoid bias, a literature search and a final consensus meeting. The authors added novel approved drugs in Brazil and the indication for phototherapy and systemic therapy for AD. The therapeutical response to systemic treatment is hereby reported in a suitable form for clinical practice and is also part of this updated manuscript.


Asunto(s)
Dermatitis Atópica , Dermatología , Humanos , Brasil , Técnica Delphi , Dermatitis Atópica/tratamiento farmacológico , Consenso , Fototerapia
4.
Inflamm Res ; 72(6): 1257-1274, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37212867

RESUMEN

OBJECTIVE AND DESIGN: The discovery of new inflammatory pathways and the mechanism of action of inflammatory, autoimmune, genetic, and neoplastic diseases led to the development of immunologically driven drugs. We aimed to perform a narrative review regarding the rising of a new class of drugs capable of blocking important and specific intracellular signals in the maintenance of these pathologies: the small molecules. MATERIALS/METHODS: A total of 114 scientific papers were enrolled in this narrative review. RESULTS: We describe in detail the families of protein kinases-Janus Kinase (JAK), Src kinase, Syk tyrosine kinase, Mitogen-Activated Protein Kinase (MAPK), and Bruton Tyrosine Kinase (BTK)-their physiologic function and new drugs that block these pathways of intracellular signaling. We also detail the involved cytokines and the main metabolic and clinical implications of these new medications in the field of dermatology. CONCLUSIONS: Despite having lower specificity compared to specific immunobiological therapies, these new drugs are effective in a wide variety of dermatological diseases, especially diseases that had few therapeutic options, such as psoriasis, psoriatic arthritis, atopic dermatitis, alopecia areata, and vitiligo.


Asunto(s)
Dermatología , Psoriasis , Vitíligo , Humanos , Autoinmunidad , Psoriasis/tratamiento farmacológico , Inflamación/tratamiento farmacológico , Quinasas Janus/metabolismo
5.
An. bras. dermatol ; 98(6): 814-836, 2023. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1520040

RESUMEN

Abstract This publication is an update of the "Consensus on the therapeutic management of atopic dermatitis - Brazilian Society of Dermatology" published in 2019, considering the novel, targeted-oriented systemic therapies for atopic dermatitis. The initial recommendations of the current consensus for systemic treatment of patients with atopic dermatitis were based on a recent review of scientific published data and a consensus was reached after voting. The Brazilian Society of Dermatology invited 31 experts from all regions of Brazil and 2 international experts on atopic dermatitis who fully contributed to the process. The methods included an e-Delphi study to avoid bias, a literature search and a final consensus meeting. The authors added novel approved drugs in Brazil and the indication for phototherapy and systemic therapy for AD. The therapeutical response to systemic treatment is hereby reported in a suitable form for clinical practice and is also part of this updated manuscript.

6.
An Bras Dermatol ; 94(2 Suppl 1): 67-75, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31166406

RESUMEN

BACKGROUND: Atopic dermatitis is a highly prevalent inflammatory and pruritic dermatosis with a multifactorial etiology, which includes skin barrier defects, immune dysfunction, and microbiome alterations. Atopic dermatitis is mediated by genetic, environmental, and psychological factors and requires therapeutic management that covers all the aspects of its complex pathogenesis. OBJECTIVES: The aim of this article is to present the experience, opinions, and recommendations of Brazilian dermatology experts regarding the therapeutic management of atopic dermatitis. METHODS: Eighteen experts from 10 university hospitals with experience in atopic dermatitis were appointed by the Brazilian Society of Dermatology to organize a consensus on the therapeutic management of atopic dermatitis. The 18 experts answered an online questionnaire with 14 questions related to the treatment of atopic dermatitis. Afterwards, they analyzed the recent international guidelines on atopic dermatitis of the American Academy of Dermatology, published in 2014, and of the European Academy of Dermatology and Venereology, published in 2018. Consensus was defined as approval by at least 70% of the panel. RESULTS/CONCLUSION: The experts stated that the therapeutic management of atopic dermatitis is based on skin hydration, topical anti-inflammatory agents, avoidance of triggering factors, and educational programs. Systemic therapy, based on immunosuppressive agents, is only indicated for severe refractory disease and after failure of topical therapy. Early detection and treatment of secondary bacterial and viral infections is mandatory, and hospitalization may be needed to control atopic dermatitis flares. Novel target-oriented drugs such as immunobiologicals are invaluable therapeutic agents for atopic dermatitis.


Asunto(s)
Consenso , Dermatitis Atópica/tratamiento farmacológico , Administración Tópica , Corticoesteroides/uso terapéutico , Antiinfecciosos/uso terapéutico , Antiinflamatorios/uso terapéutico , Brasil , Inhibidores de la Calcineurina/uso terapéutico , Dermatología , Humanos , Índice de Severidad de la Enfermedad , Sociedades Médicas , Terapia Ultravioleta
7.
An. bras. dermatol ; 94(2,supl.1): 67-75, Mar.-Apr. 2019. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1011092

RESUMEN

Abstract: BACKGROUND: Atopic dermatitis is a highly prevalent inflammatory and pruritic dermatosis with a multifactorial etiology, which includes skin barrier defects, immune dysfunction, and microbiome alterations. Atopic dermatitis is mediated by genetic, environmental, and psychological factors and requires therapeutic management that covers all the aspects of its complex pathogenesis. OBJECTIVES: The aim of this article is to present the experience, opinions, and recommendations of Brazilian dermatology experts regarding the therapeutic management of atopic dermatitis. METHODS: Eighteen experts from 10 university hospitals with experience in atopic dermatitis were appointed by the Brazilian Society of Dermatology to organize a consensus on the therapeutic management of atopic dermatitis. The 18 experts answered an online questionnaire with 14 questions related to the treatment of atopic dermatitis. Afterwards, they analyzed the recent international guidelines on atopic dermatitis of the American Academy of Dermatology, published in 2014, and of the European Academy of Dermatology and Venereology, published in 2018. Consensus was defined as approval by at least 70% of the panel. RESULTS/CONCLUSION: The experts stated that the therapeutic management of atopic dermatitis is based on skin hydration, topical anti-inflammatory agents, avoidance of triggering factors, and educational programs. Systemic therapy, based on immunosuppressive agents, is only indicated for severe refractory disease and after failure of topical therapy. Early detection and treatment of secondary bacterial and viral infections is mandatory, and hospitalization may be needed to control atopic dermatitis flares. Novel target-oriented drugs such as immunobiologicals are invaluable therapeutic agents for atopic dermatitis.


Asunto(s)
Humanos , Consenso , Dermatitis Atópica/tratamiento farmacológico , Sociedades Médicas , Terapia Ultravioleta , Índice de Severidad de la Enfermedad , Brasil , Administración Tópica , Corticoesteroides/uso terapéutico , Dermatología , Inhibidores de la Calcineurina/uso terapéutico , Antiinfecciosos/uso terapéutico , Antiinflamatorios/uso terapéutico
8.
Mol Genet Metab ; 114(2): 138-45, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25541102

RESUMEN

Mucopolysaccharidosis type I (MPS I) is due to deficient alpha-L-iduronidase (IDUA) which leads to storage of undegraded glycosaminoglycans (GAG). The severe form of the disease is characterized by mental retardation of unknown etiology. Trying to unveil the mechanisms that lead to cognitive impairment in MPS I, we studied alterations in the proteome from MPS I mouse hippocampus. Eight-month old mice presented increased LAMP-1 expression, GAG storage in neurons and glial cells, and impaired aversive and non-aversive memory. Shotgun proteomics was performed and 297 proteins were identified. Of those, 32 were differentially expressed. We found elevation in proteins such as cathepsins B and D; however their increase did not lead to cell death in MPS I brains. Glial fibrillary acid protein (GFAP) was markedly elevated, and immunohistochemistry confirmed a neuroinflammatory process that could be responsible for neuronal dysfunction. We didn't observe any differences in ubiquitin expression, as well as in other proteins related to protein folding, suggesting that the ubiquitin system is working properly. Finally, we observed alterations in several proteins involved in synaptic plasticity, including overexpression of post synaptic density-95 (PSD95) and reduction of microtubule-associated proteins 1A and 1B. These results together suggest that the cognitive impairment in MPS I mice is not due to massive cell death, but rather to neuronal dysfunction caused by multiple processes, including neuroinflammation and alterations in synaptic plasticity.


Asunto(s)
Trastornos del Conocimiento/etiología , Cognición , Hipocampo/metabolismo , Mucopolisacaridosis I/complicaciones , Mucopolisacaridosis I/metabolismo , Proteoma/análisis , Proteómica , Animales , Encéfalo/fisiopatología , Catepsina B/metabolismo , Catepsina D/metabolismo , Catepsina D/farmacología , Modelos Animales de Enfermedad , Proteína Ácida Fibrilar de la Glía/metabolismo , Glicosaminoglicanos/metabolismo , Hipocampo/fisiopatología , Iduronidasa/deficiencia , Proteínas de Membrana de los Lisosomas/genética , Proteínas de Membrana de los Lisosomas/metabolismo , Ratones , Mucopolisacaridosis I/fisiopatología , Neuroglía/metabolismo , Neuronas/metabolismo
9.
Arch Biochem Biophys ; 538(2): 80-94, 2013 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-23988349

RESUMEN

Tuberculosis (TB) is a major global health threat. There is a need for the development of more efficient drugs for the sterilization of the disease's causative agent, Mycobacterium tuberculosis (MTB). A more comprehensive understanding of the bacilli's nucleotide metabolic pathways could aid in the development of new anti-mycobacterial drugs. Here we describe expression and purification of recombinant iunH-encoded nucleoside hydrolase from MTB (MtIAGU-NH). Glutaraldehyde cross-linking results indicate that MtIAGU-NH predominates as a monomer, presenting varied oligomeric states depending upon binding of ligands. Steady-state kinetics results show that MtIAGU-NH has broad substrate specificity, accepting inosine, adenosine, guanosine, and uridine as substrates. Inosine and adenosine displayed positive homotropic cooperativity kinetics, whereas guanosine and uridine displayed hyperbolic saturation curves. Measurements of kinetics of ribose binding to MtIAGU-NH by fluorescence spectroscopy suggest two pre-existing forms of enzyme prior to ligand association. The intracellular concentrations of inosine, uridine, hypoxanthine, and uracil were determined and thermodynamic parameters estimated. Thermodynamic activation parameters (Ea, ΔG(#), ΔS(#), ΔH(#)) for MtIAGU-NH-catalyzed chemical reaction are presented. Results from mass spectrometry, isothermal titration calorimetry (ITC), pH-rate profile experiment, multiple sequence alignment, and molecular docking experiments are also presented. These data should contribute to our understanding of the biological role played by MtIAGU-NH.


Asunto(s)
Mycobacterium tuberculosis/enzimología , N-Glicosil Hidrolasas/química , N-Glicosil Hidrolasas/metabolismo , Tuberculosis/microbiología , Secuencia de Aminoácidos , Calcio/análisis , Clonación Molecular , Humanos , Concentración de Iones de Hidrógeno , Cinética , Modelos Moleculares , Datos de Secuencia Molecular , Mycobacterium tuberculosis/química , Mycobacterium tuberculosis/genética , N-Glicosil Hidrolasas/genética , N-Glicosil Hidrolasas/aislamiento & purificación , Conformación Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Alineación de Secuencia , Especificidad por Sustrato , Termodinámica
10.
An Bras Dermatol ; 87(5): 697-702, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23044560

RESUMEN

BACKGROUND: Skin diseases cause negative impact on the emotional state, social relationships and daily activities, due to the stigma caused by the appearance of the lesions. OBJECTIVE: This study aimed to assess the quality of life of pediatric patients with skin diseases attending a dermatology service, compare the scores obtained among the dermatoses found in the sample and associate them to the variables, in addition to observing how the skin disease specifically affects quality of life. METHODS: Cross-sectional study, with patients between 5 and 16 years attending the Dermatology Service of the University of Health Sciences of Porto Alegre, Brazil, between July 2010 and February 2011. The data collection instruments were the Children's Dermatology Life Quality Index questionnaire and the AUEQI questionnaire. RESULTS: A total of 161 patients were interviewed, with mean age of 9,66 years. The main dermatoses were atopic dermatitis (29.8%), warts (13%) and molluscum contagiosum (7.5%). Chronic diseases (73.9%) were the most prevalent. The overall mean Children's Dermatology Life Quality Index score was 5.01 for chronic dermatoses and 2.07 for acute illnesses, indicating a compromised quality of life among chronically ill patients. The comparison between the scores obtained with the AUEQI scale and the Children's Dermatology Life Quality Index scores indicates that the overall quality of life is less affected than the specific quality of life related to the dermatosis. CONCLUSIONS: The data presented reinforce how important it is that the patients, their families and caregivers understand the symptoms, triggers and treatment of the skin disease in question. This information facilitates adherence to the treatment and justifies the conduct adopted by the dermatologist.


Asunto(s)
Calidad de Vida , Enfermedades de la Piel/psicología , Adolescente , Alopecia Areata/psicología , Niño , Preescolar , Enfermedad Crónica , Estudios Transversales , Dermatitis Atópica/psicología , Femenino , Humanos , Masculino , Molusco Contagioso/psicología , Psoriasis/psicología , Índice de Severidad de la Enfermedad , Encuestas y Cuestionarios , Vitíligo/psicología , Verrugas/psicología
11.
An. bras. dermatol ; 87(5): 697-702, Sept-Oct. 2012. graf, tab
Artículo en Inglés | LILACS | ID: lil-651560

RESUMEN

BACKGROUND: Skin diseases cause negative impact on the emotional state, social relationships and daily activities, due to the stigma caused by the appearance of the lesions. OBJECTIVE: This study aimed to assess the quality of life of pediatric patients with skin diseases attending a dermatology service, compare the scores obtained among the dermatoses found in the sample and associate them to the variables, in addition to observing how the skin disease specifically affects quality of life. METHODS: Cross-sectional study, with patients between 5 and 16 years attending the Dermatology Service of the University of Health Sciences of Porto Alegre, Brazil, between July 2010 and February 2011. The data collection instruments were the Children's Dermatology Life Quality Index questionnaire and the AUEQI questionnaire. RESULTS: A total of 161 patients were interviewed, with mean age of 9,66 years. The main dermatoses were atopic dermatitis (29.8%), warts (13%) and molluscum contagiosum (7.5%). Chronic diseases (73.9%) were the most prevalent. The overall mean Children's Dermatology Life Quality Index score was 5.01 for chronic dermatoses and 2.07 for acute illnesses, indicating a compromised quality of life among chronically ill patients. The comparison between the scores obtained with the AUEQI scale and the Children's Dermatology Life Quality Index scores indicates that the overall quality of life is less affected than the specific quality of life related to the dermatosis. CONCLUSIONS: The data presented reinforce how important it is that the patients, their families and caregivers understand the symptoms, triggers and treatment of the skin disease in question. This information facilitates adherence to the treatment and justifies the conduct adopted by the dermatologist.


FUNDAMENTOS: Doenças dermatológicas, em razão dos estigmas pela aparência das lesões, são fonte de impacto negativo no estado emocional, relações sociais e atividades cotidianas. OBJETIVOS: Este estudo objetiva avaliar a qualidade de vida nos pacientes dermatológicos pediátricos em um centro de referência em dermatologia, comparar os índices de qualidade de vida entre as dermatoses e associá-los às variáveis, além de avaliar de que forma as dermatoses afetam a qualidade de vida especificamente. MÉTODOS: Estudo analítico transversal, pacientes entre 5 e 16 anos, do Serviço de Dermatologia da Universidade Federal de Ciências da Saúde de Porto Alegre, entre julho de 2010 e fevereiro de 2011. Instrumentos utilizados: questionário Índice Pediátrico de Qualidade de Vida em Dermatologia e escala AUQEI. RESULTADOS: Um total de 161 pacientes, média de idade de 9,66 anos. As principais dermatoses foram dermatite atópica (29,8%), verrugas vulgares (13%) e molusco contagioso (7,5%). Doenças crônicas (73,9%) foram mais prevalentes. A média do Índice Pediátrico de Qualidade de Vida em Dermatologia de 5,01 para dermatoses crônicas, e de 2,07 em agudas, indicando maior comprometimento da qualidade de vida entre os pacientes cronicamente enfermos. A comparação entre os escores obtivos com a escala AUEQI e o Índice Pediátrico de Qualidade de Vida em Dermatologia indicam que a qualidade de vida global é afetada com menor intensidade do que a relacionada especificamente à dermatose. CONCLUSÃO: Os dados obtidos reforçam a importância do entendimento dos sintomas, desencadeantes e da terapêutica da dermatose em questão pelos pacientes, por seus familiares e por seus cuidadores. Tais infomações facilitam a aderência ao tratamento e justificam a conduta adotada pelo dermatologista.


Asunto(s)
Adolescente , Niño , Preescolar , Femenino , Humanos , Calidad de Vida , Enfermedades de la Piel/psicología , Alopecia Areata/psicología , Enfermedad Crónica , Estudios Transversales , Dermatitis Atópica/psicología , Molusco Contagioso/psicología , Psoriasis/psicología , Índice de Severidad de la Enfermedad , Encuestas y Cuestionarios , Vitíligo/psicología , Verrugas/psicología
12.
Int J Parasitol ; 42(7): 635-45, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22584130

RESUMEN

The cattle tick, Rhipicephalus (Boophilus) microplus, is a haematophagous arthropod responsible for considerable losses in the livestock industry. Immunological control with vaccines is a promising alternative to replace chemical acaricides. Due to their importance in parasite physiology, cysteine endopeptidases are potential targets. In a previous study, native Vitellin Degrading Cysteine Endopeptidase (VTDCE) was successfully tested as a vaccine antigen for bovines against R. microplus. In this work, nucleotide and amino acid VTDCE sequences were obtained from cDNA databanks, based on data from Edman sequencing and mass spectrometry. Subsequently, cloning and expression, purification, immunological and biochemical characterisation of the recombinant protein were performed to determine the biological importance of VTDCE. By Western blot, polyclonal antibodies produced against recombinant VTDCE recognised native VTDCE. Interestingly, molecular analysis showed that the VTDCE sequence has similarity to antimicrobial peptides. Indeed, experimental results revealed that VTDCE has an antimicrobial activity which is independent of endopeptidase activity. We believe that this is the first known study to show that an arthropod enzyme has antimicrobial activity.


Asunto(s)
Catepsinas/metabolismo , Rhipicephalus/enzimología , Rhipicephalus/fisiología , Secuencia de Aminoácidos , Animales , Antiinfecciosos/metabolismo , Secuencia de Bases , Catepsinas/química , Catepsinas/genética , Clonación Molecular , ADN Complementario/genética , Femenino , Expresión Génica , Espectrometría de Masas , Datos de Secuencia Molecular , Péptidos/metabolismo , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Rhipicephalus/genética , Rhipicephalus/inmunología , Análisis de Secuencia de ADN , Análisis de Secuencia de Proteína
13.
Arch Biochem Biophys ; 517(1): 1-11, 2012 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-22119138

RESUMEN

Administration of the current tuberculosis (TB) vaccine to newborns is not a reliable route for preventing TB in adults. The conversion of XMP to GMP is catalyzed by guaA-encoded GMP synthetase (GMPS), and deletions in the Shiguella flexneri guaBA operon led to an attenuated auxotrophic strain. Here we present the cloning, expression, and purification of recombinant guaA-encoded GMPS from Mycobacterium tuberculosis (MtGMPS). Mass spectrometry data, oligomeric state determination, steady-state kinetics, isothermal titration calorimetry (ITC), and multiple sequence alignment are also presented. The homodimeric MtGMPS catalyzes the conversion of XMP, MgATP, and glutamine into GMP, ADP, PP(i), and glutamate. XMP, NH(4)(+), and Mg(2+) displayed positive homotropic cooperativity, whereas ATP and glutamine displayed hyperbolic saturation curves. The activity of ATP pyrophosphatase domain is independent of glutamine amidotransferase domain, whereas the latter cannot catalyze hydrolysis of glutamine to NH(3) and glutamate in the absence of substrates. ITC data suggest random order of binding of substrates, and PP(i) is the last product released. Sequence comparison analysis showed conservation of both Cys-His-Glu catalytic triad of N-terminal Class I amidotransferase and of amino acid residues of the P-loop of the N-type ATP pyrophosphatase family.


Asunto(s)
Ligasas de Carbono-Nitrógeno/metabolismo , Mycobacterium tuberculosis/enzimología , Tuberculosis/microbiología , Adenosina Trifosfatasas/metabolismo , Secuencia de Aminoácidos , Ligasas de Carbono-Nitrógeno/química , Ligasas de Carbono-Nitrógeno/genética , Ligasas de Carbono-Nitrógeno/aislamiento & purificación , Clonación Molecular , Glutaminasa/metabolismo , Humanos , Cinética , Ligandos , Magnesio/metabolismo , Modelos Moleculares , Datos de Secuencia Molecular , Mycobacterium tuberculosis/química , Mycobacterium tuberculosis/genética , Unión Proteica , Multimerización de Proteína , Estructura Terciaria de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Alineación de Secuencia , Volumetría
14.
Mol Biosyst ; 8(2): 572-86, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22075667

RESUMEN

Tuberculosis (TB) is a chronic infectious disease caused mainly by Mycobacterium tuberculosis. The worldwide emergence of drug-resistant strains, the increasing number of infected patients among immune compromised populations, and the large number of latent infected individuals that are reservoir to the disease have underscored the urgent need of new strategies to treat TB. The nucleotide metabolism pathways provide promising molecular targets for the development of novel drugs against active TB and may, hopefully, also be effective against latent forms of the pathogen. The orotate phosphoribosyltransferase (OPRT) enzyme of the de novo pyrimidine synthesis pathway catalyzes the reversible phosphoribosyl transfer from 5'-phospho-α-D-ribose 1'-diphosphate (PRPP) to orotic acid (OA), forming pyrophosphate and orotidine 5'-monophosphate (OMP). Here we describe cloning and characterization of pyrE-encoded protein of M. tuberculosis H37Rv strain as a homodimeric functional OPRT enzyme. The M. tuberculosis OPRT true kinetic constants for forward reaction and product inhibition results suggest a Mono-Iso Ordered Bi-Bi kinetic mechanism, which has not been previously described for this enzyme family. Absence of detection of half reaction and isothermal titration calorimetry (ITC) data support the proposed mechanism. ITC data also provided thermodynamic signatures of non-covalent interactions between substrate/product and M. tuberculosis OPRT. These data provide a solid foundation on which to base target-based rational design of anti-TB agents and should inform us how to better design inhibitors of M. tuberculosis OPRT.


Asunto(s)
Mycobacterium tuberculosis/enzimología , Orotato Fosforribosiltransferasa/farmacocinética , Secuencia de Aminoácidos , Proteínas Bacterianas/genética , Proteínas Bacterianas/farmacocinética , Clonación Molecular , Pruebas de Enzimas , Expresión Génica , Mycobacterium tuberculosis/metabolismo , Orotato Fosforribosiltransferasa/genética , Alineación de Secuencia
15.
Insect Biochem Mol Biol ; 38(5): 568-80, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18405834

RESUMEN

The cellular and molecular characteristics of a cell line (BME26) derived from embryos of the cattle tick Rhipicephalus (Boophilus) microplus were studied. The cells contained glycogen inclusions, numerous mitochondria, and vesicles with heterogeneous electron densities dispersed throughout the cytoplasm. Vesicles contained lipids and sequestered palladium meso-porphyrin (Pd-mP) and rhodamine-hemoglobin, suggesting their involvement in the autophagic and endocytic pathways. The cells phagocytosed yeast and expressed genes encoding the antimicrobial peptides (microplusin and defensin). A cDNA library was made and 898 unique mRNA sequences were obtained. Among them, 556 sequences were not significantly similar to any sequence found in public databases. Annotation using Gene Ontology revealed transcripts related to several different functional classes. We identified transcripts involved in immune response such as ferritin, serine proteases, protease inhibitors, antimicrobial peptides, heat shock protein, glutathione S-transferase, peroxidase, and NADPH oxidase. BME26 cells transfected with a plasmid carrying a red fluorescent protein reporter gene (DsRed2) transiently expressed DsRed2 for up to 5 weeks. We conclude that BME26 can be used to experimentally analyze diverse biological processes that occur in R. (B.) microplus such as the innate immune response to tick-borne pathogens.


Asunto(s)
Línea Celular/ultraestructura , ARN Ribosómico 16S/genética , Rhipicephalus/embriología , Animales , Secuencia de Bases , Línea Celular/fisiología , Proliferación Celular , Cariotipificación , Microscopía Electrónica de Transmisión , Datos de Secuencia Molecular , Rhipicephalus/genética , Transfección
16.
Dev Comp Immunol ; 32(6): 716-25, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18082261

RESUMEN

Invertebrates protect themselves against microbial infection through cellular and humoral immune defenses. Since the available information on the immune system of spiders is scarce, the main goal of the present study was to investigate the role of hemocytes and antimicrobial peptides (AMPs) in defense against microbes of spider Acanthoscurria gomesiana. We previously described the purification and characterization of two AMPs from the hemocytes of naïve spider A. gomesiana, gomesin and acanthoscurrin. Here we show that 57% of the hemocytes store both gomesin and acanthoscurrin, either in the same or in different granules. Progomesin labeling in hemocyte granules indicates that gomesin is addressed to those organelles as a propeptide. In vivo and in vitro experiments showed that lipopolysaccharide (LPS) and yeast caused the hemocytes to migrate. Once they have reached the infection site, hemocytes may secrete coagulation cascade components and AMPs to cell-free hemolymph. Furthermore, our results suggest that phagocytosis is not the major defense mechanism activated after microbial challenge. Therefore, the main reactions involved in the spider immune defense might be coagulation and AMP secretion.


Asunto(s)
Péptidos Catiónicos Antimicrobianos/inmunología , Hemocitos/inmunología , Inmunidad , Proteínas de Insectos/inmunología , Arañas/inmunología , Animales , Péptidos Catiónicos Antimicrobianos/metabolismo , Factores de Coagulación Sanguínea/inmunología , Factores de Coagulación Sanguínea/metabolismo , Movimiento Celular/efectos de los fármacos , Movimiento Celular/inmunología , Perfilación de la Expresión Génica , Hemocitos/microbiología , Hemocitos/ultraestructura , Inmunohistoquímica , Proteínas de Insectos/ultraestructura , Lipopolisacáridos/farmacología , Microscopía Confocal , Micosis/inmunología , Fagocitosis/inmunología , Procesamiento Proteico-Postraduccional/efectos de los fármacos , Saccharomyces cerevisiae
17.
Curr Microbiol ; 54(4): 282-6, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17334845

RESUMEN

An antimicrobial peptide produced by a new Bacillus species isolated from the Amazon Basin was purified and characterized. The antimicrobial peptide was purified by ammonium sulfate precipitation, gel filtration, and ion exchange chromatography, and after the final purification step, one active fraction was obtained, designated BLS P34. Direct activity on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) was observed. A single band on SDS-PAGE suggested that the peptide was purified to homogeneity and had a molecular mass of about 5 kDa. The molecular weight (MW) was accurately determined by mass spectroscopy as 1456 Da. The purified BLS P34 remained active over a wide temperature range and was susceptible to all proteases tested.


Asunto(s)
Antiinfecciosos/aislamiento & purificación , Bacillus/metabolismo , Péptidos/aislamiento & purificación , Animales , Antiinfecciosos/metabolismo , Antiinfecciosos/farmacología , Bacillus/aislamiento & purificación , Cromatografía en Gel , Electroforesis en Gel de Poliacrilamida , Hemólisis/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Péptidos/metabolismo , Péptidos/farmacología , Ovinos , América del Sur , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Espectroscopía Infrarroja por Transformada de Fourier
18.
Dev Comp Immunol ; 30(6): 545-56, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16386302

RESUMEN

The present study reports the identification of immune related transcripts from hemocytes of the spider Acanthoscurria gomesiana by high throughput sequencing of expressed sequence tags (ESTs). To generate ESTs from hemocytes, two cDNA libraries were prepared: one by directional cloning (primary) and the other by the normalization of the first (normalized). A total of 7584 clones were sequenced and the identical ESTs were clustered, resulting in 3723 assembled sequences (AS). At least 20% of these sequences are putative novel genes. The automatic functional annotation of AS based on Gene Ontology revealed several abundant transcripts related to the following functional classes: hemocyanin, lectin, and structural constituents of ribosome and cytoskeleton. From this annotation, 73 transcripts possibly involved in immune response were also identified, suggesting the existence of several molecular processes not previously described for spiders, such as: pathogen recognition, coagulation, complement activation, cell adhesion and intracellular signaling pathway for the activation of cellular defenses.


Asunto(s)
Hemocitos/inmunología , Arañas/genética , Arañas/inmunología , Secuencia de Aminoácidos , Animales , Etiquetas de Secuencia Expresada , Expresión Génica , Perfilación de la Expresión Génica , Biblioteca de Genes , Datos de Secuencia Molecular , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido
20.
Bioinformatics ; 21(23): 4302-3, 2005 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-16210424

RESUMEN

SUMMARY: Growth of genome data and analysis possibilities have brought new levels of difficulty for scientists to understand, integrate and deal with all this ever-increasing information. In this scenario, GARSA has been conceived aiming to facilitate the tasks of integrating, analyzing and presenting genomic information from several bioinformatics tools and genomic databases, in a flexible way. GARSA is a user-friendly web-based system designed to analyze genomic data in the context of a pipeline. EST and GGS data can be analyzed using the system since it accepts (1) chromatograms, (2) download of sequences from GenBank, (3) Fasta files stored locally or (4) a combination of all three. Quality evaluation of chromatograms, vector removing and clusterization are easily performed as part of the pipeline. A number of local and customizable Blast and CDD analyses can be performed as well as Interpro, complemented with phylogeny analyses. GARSA is being used for the analyses of Trypanosoma vivax (GSS and EST), Trypanosoma rangeli (GSS, EST and ORESTES), Bothrops jararaca (EST), Piaractus mesopotamicus (EST) and Lutzomyia longipalpis (EST). AVAILABILITY: The GARSA system is freely available under GPL license (http://www.biowebdb.org/garsa/). For download requests visit http://www.biowebdb.org/garsa/ or contact Dr Alberto Dávila.


Asunto(s)
Biología Computacional/métodos , Animales , Bothrops/metabolismo , Cromatografía , Sistemas de Administración de Bases de Datos , Bases de Datos Genéticas , Bases de Datos de Ácidos Nucleicos , Bases de Datos de Proteínas , Etiquetas de Secuencia Expresada , Genoma , Genómica , Almacenamiento y Recuperación de la Información , Internet , Filogenia , Alineación de Secuencia , Análisis de Secuencia de ADN , Programas Informáticos , Trypanosoma/metabolismo , Trypanosoma vivax/genética , Interfaz Usuario-Computador
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