RESUMO
We investigated the effect of fish oil (FO) supplementation, at 4 g/day, on the respiratory performance and blood lipid profile of 32 patients with breast cancer at the beginning of chemotherapy. They were randomized into two groups: control (C) and FO supplemented (S). Both groups underwent three respiratory evaluations and blood harvest (before chemotherapy-Day 0, and 30 and 60 days after supplementation). The S group showed a significant increase in the maximal inspiratory and expiratory pressure (P ≤ 0.05 vs. Day 0) and in the maximum voluntary ventilation (P ≤ 0.05). In the treadmill 6-min-walk test, the S group had a significant increase in the walked distance (P ≤ 0.05). Blood lactate concentration was significantly lower in the S group after 60 days, at rest, when compared to C (P ≤ 0.05). Plasma high-density lipoprotein (HDL) cholesterol concentration remained the same after 60 days of supplementation, while in the C group, it decreased significantly (P ≤ 0.05 Day 0 vs. Day 60). Triacylglycerol (TAG) plasma concentration in the S group was lower when compared to the C group (P ≤ 0.05 Day 60S vs. Day 60). Supplementation with FO caused improvement in the respiratory muscle strength and endurance, ameliorated functional performance, and kept TAG, HDL cholesterol, and lactate plasma concentration at normal levels.
Assuntos
Antineoplásicos/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Suplementos Nutricionais , Óleos de Peixe/uso terapêutico , Pulmão/efeitos dos fármacos , Resistência Física/efeitos dos fármacos , Insuficiência Respiratória/prevenção & controle , Adulto , Antineoplásicos/uso terapêutico , Brasil , Neoplasias da Mama/sangue , Neoplasias da Mama/dietoterapia , Neoplasias da Mama/cirurgia , Quimioterapia Adjuvante/efeitos adversos , HDL-Colesterol/sangue , Suplementos Nutricionais/efeitos adversos , Teste de Esforço , Feminino , Óleos de Peixe/efeitos adversos , Humanos , Ácido Láctico/sangue , Pulmão/fisiopatologia , Pessoa de Meia-Idade , Força Muscular/efeitos dos fármacos , Cuidados Pós-Operatórios , Complicações Pós-Operatórias/induzido quimicamente , Complicações Pós-Operatórias/fisiopatologia , Complicações Pós-Operatórias/prevenção & controle , Reprodutibilidade dos Testes , Insuficiência Respiratória/induzido quimicamente , Insuficiência Respiratória/etiologia , Insuficiência Respiratória/fisiopatologia , Músculos Respiratórios/efeitos dos fármacos , Músculos Respiratórios/fisiopatologia , Triglicerídeos/sangueRESUMO
Quinolones and fluoroquinolones are widely used to treat uropathogenic Escherichia coli infections. Bacterial resistance to these antimicrobials primarily involves mutations in gyrA and parC genes. To date, no studies have examined the potential relationship between biochemical characteristics and quinolone resistance in uropathogenic E. coli strains. The present work analyzed the quinolone sensitivity and biochemical activities of fifty-eight lactose-negative uropathogenic E. coli strains. A high percentage of the isolates (48.3%) was found to be resistant to at least one of the tested quinolones, and DNA sequencing revealed quinolone resistant determining region gyrA and parC mutations in the multi-resistant isolates. Statistical analyses suggested that the lack of ornithine decarboxylase (ODC) activity is correlated with quinolone resistance. Despite the low number of isolates examined, this is the first study correlating these characteristics in lactose-negative E. coli isolates.
Assuntos
Farmacorresistência Bacteriana Múltipla/genética , Infecções por Escherichia coli/tratamento farmacológico , Fluoroquinolonas/uso terapêutico , Lactose/metabolismo , Ácido Nalidíxico/uso terapêutico , Ornitina Descarboxilase/genética , Infecções Urinárias/tratamento farmacológico , Escherichia coli Uropatogênica/genética , Antibacterianos/uso terapêutico , Brasil , DNA Girase/genética , DNA Topoisomerase IV/genética , Descarboxilação/genética , Descarboxilação/fisiologia , Infecções por Escherichia coli/microbiologia , Humanos , Testes de Sensibilidade Microbiana , Ornitina/metabolismo , Infecções Urinárias/microbiologia , Escherichia coli Uropatogênica/efeitos dos fármacos , Escherichia coli Uropatogênica/enzimologia , Escherichia coli Uropatogênica/isolamento & purificaçãoRESUMO
Quinolones and fluoroquinolones are widely used to treat uropathogenic
Assuntos
Humanos , Farmacorresistência Bacteriana Múltipla/genética , Infecções por Escherichia coli/tratamento farmacológico , Fluoroquinolonas/uso terapêutico , Lactose/metabolismo , Ácido Nalidíxico/uso terapêutico , Ornitina Descarboxilase/genética , Infecções Urinárias/tratamento farmacológico , Escherichia coli Uropatogênica/genética , Antibacterianos/uso terapêutico , Brasil , DNA Girase/genética , DNA Topoisomerase IV/genética , Descarboxilação/genética , Descarboxilação/fisiologia , Infecções por Escherichia coli/microbiologia , Testes de Sensibilidade Microbiana , Ornitina/metabolismo , Infecções Urinárias/microbiologia , Escherichia coli Uropatogênica/efeitos dos fármacos , Escherichia coli Uropatogênica/enzimologia , Escherichia coli Uropatogênica/isolamento & purificaçãoRESUMO
Brown spider bites are associated with lesions including dermonecrosis, gravitational spreading and a massive inflammatory response, along with systemic problems that may include hematological disturbances and renal failure. The mechanisms by which the venom exerts its noxious effects are currently under investigation. It is known that the venom contains a major toxin (dermonecrotic toxin, biochemically a phospholipase D) that can experimentally induce dermonecrosis, inflammatory response, animal mortality and platelet aggregation. Herein, we describe cloning, heterologous expression, purification and functionality of a novel isoform of the 33 kDa dermonecrotic toxin. Circular dichroism analysis evidenced correct folding for the toxin. The recombinant toxin was recognized by whole venom serum antibodies and by a specific antibody to a previously described dermonecrotic toxin. The identified toxin was found to display phospholipase activity and dermonecrotic properties. Additionally, the toxin caused a massive inflammatory response in rabbit skin dermis, evoked platelet aggregation, increased vascular permeability, caused edema and death in mice. These characteristics in combination with functional studies for other dermonecrotic toxins illustrate that a family of dermonecrotic toxins exists, and includes a novel member with high activity that may be useful for future structural and functional studies.
Assuntos
Derme/efeitos dos fármacos , Fosfolipase D/química , Fosfolipase D/toxicidade , Venenos de Aranha/química , Venenos de Aranha/enzimologia , Venenos de Aranha/toxicidade , Sequência de Aminoácidos , Animais , Permeabilidade Capilar/efeitos dos fármacos , Clonagem Molecular , DNA Complementar/genética , Derme/patologia , Edema/induzido quimicamente , Camundongos , Dados de Sequência Molecular , Necrose/induzido quimicamente , Fosfolipase D/genética , Diester Fosfórico Hidrolases/genética , Diester Fosfórico Hidrolases/toxicidade , Filogenia , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/toxicidade , Coelhos , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/toxicidade , Venenos de Aranha/genética , Aranhas/enzimologiaRESUMO
Loxoscelism (the condition produced by the bite of brown spiders) has been reported worldwide, but especially in warmer regions. Clinical manifestations include skin necrosis with gravitational spreading while systemic loxoscelism may include renal failure, hemolysis and thrombocytopenia. The venom contains several toxins, of which the best biochemically and biologically studied is the dermonecrotic toxin, a phospholipase-D. Purified toxin induces cutaneous and systemic loxoscelism, especially necrotic lesions, hematological disturbances and renal failure. Herein, we describe cloning, heterologous expression and purification of two novel dermonecrotic toxins: LiRecDT4 and LiRecDT5. The recombinant proteins stably expressed in Escherichia coli cells were purified from culture supernatants in a single step using Ni(2+)-chelating chromatography producing soluble proteins of 34 kDa (LiRecDT4) and 37 kDa (LiRecDT5). Circular dichroism analysis evidenced correctly folding for toxins but differences in secondary structures. Both proteins were recognized by whole venom serum antibodies and by a specific antibody to dermonecrotic toxin. Also, recombinant toxins with phospholipase activity induced experimental skin lesions and caused a massive inflammatory response in rabbit skin dermis. Nevertheless, toxins displayed different effects upon platelet aggregation, increase in vascular permeability and not caused death in mice. These characteristics in combination with functional studies illustrates that a family of dermonecrotic toxins exists, and includes two novel members that are useful for future structural and functional studies. They will also be useful in biotechnological ends, for example, as inflammatory and platelet aggregating studies, as antigens for serum therapy source and for lipids biochemical research.
Assuntos
Venenos de Aranha/genética , Venenos de Aranha/metabolismo , Aranhas/genética , Toxinas Biológicas/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Permeabilidade Capilar/efeitos dos fármacos , Dicroísmo Circular , Clonagem Molecular , DNA Complementar/química , DNA Complementar/genética , Eletroforese em Gel de Poliacrilamida , Camundongos , Dados de Sequência Molecular , Fosfolipases/genética , Fosfolipases/metabolismo , Filogenia , Agregação Plaquetária/efeitos dos fármacos , Coelhos , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/toxicidade , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Pele/efeitos dos fármacos , Pele/patologia , Aranhas/metabolismo , Toxinas Biológicas/metabolismo , Toxinas Biológicas/toxicidadeRESUMO
Brown spider (Genus Loxosceles) bites are normally associated with necrotic skin degeneration, gravitational spreading, massive inflammatory response at injured region, platelet aggregation causing thrombocytopenia and renal disturbances. Brown spider venom has a complex composition containing many different toxins, of which a well-studied component is the dermonecrotic toxin. This toxin alone may produce necrotic lesions, inflammatory response and platelet aggregation. Biochemically, dermonecrotic toxin belongs to a family of toxins with 30-35 kDa characterized as sphingomyelinase-D. Here, employing a cDNA library of Loxosceles intermedia venom gland, we cloned and expressed two recombinant isoforms of the dermonecrotic toxin LiRecDT2 (1062 bp cDNA) and LiRecDT3 (1007 bp cDNA) that encode for signal peptides and complete mature proteins. Phylogenetic tree analysis revealed a structural relationship for these toxins compared to other members of family. Recombinant molecules were expressed as N-terminal His-tag fusion proteins in Escherichia coli and were purified to homogeneity from cell lysates by Ni(2+) chelating chromatography, resulting in proteins of 33.8 kDa for LiRecDT2 and 34.0 kDa for LiRecDT3. Additional evidence for related toxins containing sequence/epitopes identity comes from antigenic cross-reactivity using antibodies against crude venom toxins and antibodies raised with a purified dermonecrotic toxin. Recombinant toxins showed differential functionality in rabbits: LiRecDT2 caused a macroscopic lesion with gravitational spreading upon intradermal injection, while LiRecDT3 evoked transient swelling and erythema upon injection site. Light microscopic analysis of skin biopsies revealed edema, a collection of inflammatory cells in and around blood vessels and a proteinaceous network at the dermis. Moreover, differential functionality for recombinant toxins was also demonstrated by a high sphingomyelinase activity for LiRecDT2 and low activity for LiRecDT3 as well as greater in vitro platelet aggregation and blood vessel permeability induced by LiRecDT2 and residual activity for LiRecDT3. Cloning and expression of two recombinant dermonecrotic toxins demonstrate an intraspecific family of homologous toxins that act in synergism for deleterious activities of the venom and open possibilities for biotechnological applications for recombinant toxins as research tools for understanding the inflammatory response, vascular integrity and platelet aggregation modulators.
Assuntos
Diester Fosfórico Hidrolases/química , Diester Fosfórico Hidrolases/genética , Venenos de Aranha/química , Venenos de Aranha/genética , Aranhas/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , Camundongos , Dados de Sequência Molecular , Diester Fosfórico Hidrolases/farmacologia , Filogenia , Agregação Plaquetária/efeitos dos fármacos , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/farmacologia , Coelhos , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/farmacologia , Alinhamento de Sequência , Esfingomielina Fosfodiesterase/metabolismo , Venenos de Aranha/farmacologia , Aranhas/químicaRESUMO
Accidents caused by brown spiders (Loxosceles genus) are classically associated with dermonecrotic lesions and systemic manifestations including intravascular haemolysis, disseminated intravascular coagulation and acute renal failure. Systemic reactions occur in a minority of cases, but may be severe in some patients and occasionally fatal. The mechanisms by which Loxosceles venom exerts these noxious effects are currently under investigation. The venom contains several toxins, some of which have been well-characterised biochemically and biologically. The purpose of the present review is to describe some insights into loxoscelism obtained over the last ten years. The biology and epidemiology of the brown spider, the histopathology of envenomation and the immunogenicity of Loxosceles venom are reviewed, as are the clinical features, diagnosis and therapy of brown spider bites. The identification and characterisation of some toxins and the mechanism of induction of local and systemic lesions caused by brown spider venom are also discussed. Finally, the biotechnological application of some venom toxins are covered.
Assuntos
Diester Fosfórico Hidrolases/química , Diester Fosfórico Hidrolases/imunologia , Picada de Aranha/epidemiologia , Picada de Aranha/patologia , Venenos de Aranha/química , Venenos de Aranha/imunologia , Aranhas/química , Animais , Biotecnologia , Brasil/epidemiologia , Diester Fosfórico Hidrolases/toxicidade , Picada de Aranha/diagnóstico , Picada de Aranha/terapia , Venenos de Aranha/toxicidade , Aranhas/fisiologiaRESUMO
Loxoscelism, the term used to describe envenomation with brown spiders, is characterized by a dermonecrotic lesion at the bite site. In the present investigation we submitted albino rabbits to an acute experimental envenomation protocol using Loxosceles intermedia (brown spider) venom, with in order to determine the pathogenesic features of the lesion induced by this spider, which is the cause of several accidents throughout the world. Rabbits received intradermal injections of the venom and were monitored over the first 4 h, and then at 12 h and 1, 2 and 5 days after envenomation. Histological specimens from 3 rabbits per time point were collected from euthanized animals and processed for histological examination by light microscopy. Major findings observed during the first 4 h were oedema, haemorrhage, degeneration of blood vessel walls, plasma exudation, thrombosis, neutrophil accumulation in and around blood vessels with an intensive diapedesis, a diffuse collection of inflammatory cells (polymorphonuclear leucocytes) in the dermis, and subcutaneous muscular oedema. Over the following hours and up to 5 days after envenomation the changes progressed to massive neutrophil infiltration (with no other leucocytes) into the dermis and even into subcutaneous muscle tissue, destruction of blood vessels, thrombosis, haemorrhage, myonecrosis, and coagulative necrosis on the 5th day.