RESUMEN
Snakebite accidents are a public health problem that affects the whole world, causing thousands of deaths and amputations each year. In Brazil, snakebite envenomations are caused mostly by snakes from the Bothrops genus. The local symptoms are characterized by pain, swelling, ecchymosis, and hemorrhages. Systemic disturbances can lead to necrosis and amputations. The present treatment consists of intravenous administration of bothropic antivenom, which is capable of reversing most of the systemic symptoms, while presenting limitations to treat the local effects, such as hemorrhage and to neutralize the snake venom serine protease (SVSP). In this context, we aimed to evaluate the activity of selective serine protease inhibitors (pepC and pepB) in combination with the bothropic antivenom in vivo. Further, we assessed their possible synergistic effect in the treatment of coagulopathy and hemorrhage induced by Bothrops jararaca venom. For this, we evaluated the in vivo activity in mouse models of local hemorrhage and a series of in vitro hemostasis assays. Our results showed that pepC and pepB, when combinated with the antivenom, increase its protective activity in vivo and decrease the hemostatic disturbances in vitro with high selectivity, possibly by inhibiting botropic proteases. These data suggest that the addition of serine protease inhibitor to the antivenom can improve its overall potential.
Asunto(s)
Bothrops , Venenos de Crotálidos , Animales , Antivenenos/farmacología , Antivenenos/uso terapéutico , Brasil , Venenos de Crotálidos/toxicidad , Hemorragia/inducido químicamente , Hemorragia/tratamiento farmacológico , Ratones , Inhibidores de Serina Proteinasa/farmacología , Inhibidores de Serina Proteinasa/uso terapéuticoRESUMEN
The increase of contact between natural and rural areas is prominent in Brazil, due to agricultural activities and concern with the environmental conservation. In this context, domestic animals, wild fauna and humans are exposed to mutual exchange of parasites, microorganisms and diseases. We studied tick parasitism of wild carnivores and domestic dogs, and the environmental of questing ticks, in extensive cattle ranch areas intermingled with natural vegetation, and in a natural reserve, both in a region of Cerrado biome, Midwestern Brazil. From 2008 to 2015, we inspected 119 wild carnivores from nine species, and collected six tick species (Amblyomma sculptum, Amblyomma ovale, Amblyomma dubitatum, Amblyomma tigrinum, Dermacentor nitens and Rhipicephalus microplus). The most numerous and infested hosts were Cerdocyon thous, Lycalopex vetulus, Chrysocyon brachyurus, Puma concolor and Conepatus amazonicus. From 139 domestic dogs, we collected A. sculptum, Rhipicephalus sanguineus and R. microplus. From vegetation, samplings resulted in A. sculptum, A. dubitatum, A. ovale, Amblyomma rotundatum and R. microplus, with dominance of A. sculptum. Domestics and wild animals presented high overlapping of infestations by A. sculptum, a generalist and anthropophilic tick species. This tick is the most important vector of the Brazilian spotted fever, a lethal human disease. This fact elicits attention and requires efforts to monitor the presence of pathogens vectored by ticks circulating in this type of agroecosystem, including in other regions of the Brazil, because the most of the natural vegetation remaining have been increasingly immersed in pastures and agricultural matrix.
Asunto(s)
Amblyomma/fisiología , Carnívoros , Dermacentor/fisiología , Enfermedades de los Perros/epidemiología , Rhipicephalus/fisiología , Infestaciones por Garrapatas/epidemiología , Amblyomma/crecimiento & desarrollo , Animales , Brasil/epidemiología , Dermacentor/crecimiento & desarrollo , Enfermedades de los Perros/parasitología , Perros , Ecosistema , Femenino , Larva/crecimiento & desarrollo , Larva/fisiología , Masculino , Ninfa/crecimiento & desarrollo , Ninfa/fisiología , Prevalencia , Rhipicephalus/crecimiento & desarrollo , Infestaciones por Garrapatas/parasitologíaRESUMEN
Statins are inhibitors of cholesterol synthesis, but other biological properties, such as antimicrobial effects, have also been assigned to them, leading to their designation as pleiotropic agents. Our goal was to investigate the activity and selectivity of atorvastatin (AVA) against Trypanosoma cruzi by using in vitro models, aiming for more effective and safer therapeutic options through drug repurposing proposals for monotherapy and therapy in combination with benznidazole (BZ). Phenotypic screening was performed with different strains (Tulahuen [discrete typing unit {DTU} VI] and Y [DTU II]) and forms (intracellular forms, bloodstream trypomastigotes, and tissue-derived trypomastigotes) of the parasite. On assay of the Tulahuen strain, AVA was more active against intracellular amastigotes (selectivity index [SI] = 3). Also, against a parasite of another DTU (Y strain), this statin was more active (2.1-fold) and selective (2.4-fold) against bloodstream trypomastigotes (SI = 51) than against the intracellular forms (SI = 20). A cytomorphological approach using phalloidin-rhodamine permitted us to verify that AVA did not induced cell density reduction and that cardiac cells (CC) maintained their typical cytoarchitecture. Combinatory approaches using fixed-ratio methods showed that AVA and BZ gave synergistic interactions against both trypomastigotes and intracellular forms (mean sums of fractional inhibitory concentration indexes [∑FICIs] of 0.46 ± 0.12 and 0.48 ± 0.03, respectively). Thus, the repurposing strategy for AVA, especially in combination with BZ, which leads to a synergistic effect, is encouraging for future studies to identify novel therapeutic protocols for Chagas disease treatment.
Asunto(s)
Atorvastatina/farmacología , Enfermedad de Chagas/tratamiento farmacológico , Nitroimidazoles/farmacología , Tripanocidas/farmacología , Trypanosoma cruzi/efectos de los fármacos , Animales , Línea Celular , Enfermedad de Chagas/parasitología , Reposicionamiento de Medicamentos/métodos , Sinergismo Farmacológico , Quimioterapia Combinada/métodos , Corazón/parasitología , Ratones , Pruebas de Sensibilidad Parasitaria/métodosRESUMEN
Mayaro fever, caused by Mayaro virus (MAYV) is a sub-lethal disease with symptoms that are easily confused with those of dengue fever, except for polyarthralgia, which may culminate in physical incapacitation. Recently, outbreaks of MAYV have been documented in metropolitan areas, and to date, there is no therapy or vaccine available. Moreover, there is no information regarding the three-dimensional structure of the viral proteins of MAYV, which is important in the search for antivirals. In this work, we constructed a three-dimensional model of protein C of MAYV by homology modelling, and this was employed in a manner similar to that of receptors in virtual screening studies to evaluate 590 molecules as prospective antiviral agents. In vitro bioassays were utilized to confirm the potential antiviral activity of the flavonoid epicatechin isolated from Salacia crassifolia (Celastraceae). The virtual screening showed that six flavonoids were promising ligands for protein C. The bioassays showed potent antiviral action of epicatechin, which protected the cells from almost all of the effects of viral infection. An effective concentration (EC50) of 0.247 µmol/mL was observed with a selectivity index (SI) of 7. The cytotoxicity assay showed that epicatechin has low toxicity, with a 50% cytotoxic concentration (CC50) greater than 1.723 µmol/mL. Epicatechin was found to be twice as potent as the reference antiviral ribavirin. Furthermore, a replication kinetics assay showed a strong inhibitory effect of epicatechin on MAYV growth, with a reduction of at least four logs in virus production. Our results indicate that epicatechin is a promising candidate for further testing as an antiviral agent against Mayaro virus and other alphaviruses.
Asunto(s)
Alphavirus/química , Antígenos Virales/química , Antivirales/farmacología , Catequina/farmacología , Salacia/química , Proteínas Virales/química , Alphavirus/metabolismo , Animales , Antígenos Virales/metabolismo , Antivirales/química , Antivirales/aislamiento & purificación , Sitios de Unión , Catequina/química , Catequina/aislamiento & purificación , Chlorocebus aethiops , Ensayos Analíticos de Alto Rendimiento , Humanos , Concentración 50 Inhibidora , Simulación del Acoplamiento Molecular , Unión Proteica , Conformación Proteica en Hélice alfa , Conformación Proteica en Lámina beta , Dominios y Motivos de Interacción de Proteínas , Ribavirina/química , Ribavirina/farmacología , Homología Estructural de Proteína , Interfaz Usuario-Computador , Células Vero , Proteínas Virales/antagonistas & inhibidores , Proteínas Virales/metabolismo , Replicación Viral/efectos de los fármacosRESUMEN
Fifteen novel arylimidamides (AIAs) (6 bis-amidino and 9 mono-amidino analogues) were assayed against Trypanosoma cruzi in vitro and in vivo. All the bis-AIAs were more effective than the mono-AIAs, and two analogues, DB1967 and DB1989, were further evaluated in vivo. Although both of them reduced parasitemia, protection against mortality was not achieved. Our results show that the number of amidino-terminal units affects the efficacy of arylimidamides against T. cruzi.
Asunto(s)
Amidinas/uso terapéutico , Enfermedad de Chagas/tratamiento farmacológico , Parasitemia/tratamiento farmacológico , Tripanocidas/uso terapéutico , Trypanosoma cruzi/efectos de los fármacos , Amidinas/química , Animales , Enfermedad de Chagas/mortalidad , Enfermedad de Chagas/parasitología , Masculino , Ratones , Parasitemia/mortalidad , Parasitemia/parasitología , Pruebas de Sensibilidad Parasitaria , Tripanocidas/químicaRESUMEN
PURPOSE: It is recognized that chronic inflammation can cause cancer. Even though most of the available synthetic meshes are considered non-carcinogenic, the inflammatory response to an infected mesh plays a constant aggression to the skin. Chronic mesh infection is frequently the result of misuse of mesh, and due to the challenging nature of this condition, patients usually suffer for years until the infected mesh is removed by surgical excision. METHODS: We report two cases of squamous-cell carcinoma (SCC) of the abdominal wall, arising in patients with long-term mesh infection. RESULTS: In both patients, the degeneration of mesh infection into SCC was presumably caused by the long-term inflammation secondary to infection. Patients presented with advanced SCC behaving just like the Marjolin's ulcers of burns. Radical surgical excision was the treatment of choice. The involvement of the bowel played an additional challenge in case 1, but it was possible to resect the tumor and the involved bowel and reconstruct the abdominal wall using polypropylene mesh as onlay reinforcement, in a single stage operation. He is now under adjuvant chemotherapy. The big gap in the midline after tumor resection in case 2 required mesh bridging to close the defect. The poor prognosis of case 2 who died months after the operation, and the involvement of the armpit, groin and mesenteric nodes in case 1 shows how aggressive this disease can be. CONCLUSION: Infected mesh must be treated early, by complete excision of the mesh. Long-standing mesh infection can degenerate into aggressive squamous-cell carcinoma of the skin.
Asunto(s)
Pared Abdominal/patología , Carcinoma de Células Escamosas/etiología , Infecciones Relacionadas con Prótesis/complicaciones , Mallas Quirúrgicas/efectos adversos , Pared Abdominal/cirugía , Materiales Biocompatibles/efectos adversos , Carcinoma de Células Escamosas/cirugía , Humanos , Masculino , Persona de Mediana Edad , Poliésteres/efectos adversos , Infecciones Relacionadas con Prótesis/etiologíaRESUMEN
A peptide based on a fragment of hair keratin type II cuticular protein, keratin peptide (KP), was studied as a possible strengthening agent for weakened relaxed hair. The peptide was prepared both in aqueous water formulation (WF) and organic solvent formulations (OF), to determine the effect of organic solvents on peptide interaction with hair and the differences in hair recovery. Both peptide formulations were shown to improve mechanical and thermal properties of weakened hair with peptide in OF showing the stronger effect. As a potential new hair care product, and so would necessitate contact with skin, the cytotoxicity and genotoxicity of the peptide were also evaluated through different methodologies (Alamar Blue assay, 2'-7'-dichlorofluorescein probe, cell morphology and growth and evaluation of DNA damage by an alkaline version of the comet assay) in skin fibroblasts. These tests are indicators of the potential of peptide to cause irritation on skin or to be carcinogenic, respectively. The peptide in WF did not cause cytotoxicity or genotoxicity in any of the concentrations tested. The presence of OF, however, induced a 20% decrease in cell viability in all of the range of concentrations used after 72-h incubation. Moreover, OF inhibited cell growth and was considered genotoxic at first contact with cells. The peptide was therefore considered a promising strengthening agent for hair and was shown to be innocuous when applied in WF.
Asunto(s)
Preparaciones para el Cabello/administración & dosificación , Cabello/efectos de los fármacos , Queratinas/administración & dosificación , Negro o Afroamericano , Rastreo Diferencial de Calorimetría , Supervivencia Celular/efectos de los fármacos , Ensayo Cometa , Daño del ADN , Fibroblastos/citología , Fibroblastos/efectos de los fármacos , Cabello/metabolismo , Cabello/ultraestructura , Humanos , Microscopía de Contraste de Fase , Pruebas de Mutagenicidad , Resistencia a la TracciónRESUMEN
BACKGROUND: The Frontal Assessment Battery (FAB) is a short tool for the assessment of executive functions consisting of six subtests that explore different abilities related to the frontal lobes. Several studies have indicated that executive dysfunction is the main neuropsychological feature in Parkinson's disease (PD). GOALS: To evaluate the clinical usefulness of the FAB in identifying executive dysfunction in PD; to determine if FAB scores in PD are correlated with formal measures of executive functions; and to provide normative data for the Portuguese version of the FAB. METHODS: The study involved 122 healthy participants and 50 idiopathic PD patients. We compared FAB scores in normal controls and in PD patients matched for age, education and Mini-Mental State Examination (MMSE) score. In PD patients, FAB results were compared to the performance on tests of executive functioning. RESULTS: In the healthy subjects, FAB scores varied as a function of age, education and MMSE. In PD, FAB scores were significantly decreased compared to normal controls, and correlated with measures of executive functions such as phonemic and semantic verbal fluency tests, Wisconsin Card Sorting Test and Trail Making Test Part A and Part B. CONCLUSION: The FAB is a useful tool for the screening of executive dysfunction in PD, showing good discriminant and concurrent validities. Normative data provided for the Portuguese version of this test improve the accuracy and confidence in the clinical use of the FAB.
Asunto(s)
Procesos Mentales , Pruebas Neuropsicológicas , Enfermedad de Parkinson/fisiopatología , Adulto , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Cognición , Humanos , Persona de Mediana Edad , Enfermedad de Parkinson/psicología , Portugal , Adulto JovenRESUMEN
In the present study, the chemoprotective effects of quercetin, rutin and ursolic acid on tert-butyl hydroperoxide (t-BHP)-induced DNA damage in a human hepatoma cell line (HepG2) were investigated by the comet assay. To determine whether protection was due to direct chemical interactions alone or to cellular-mediated responses three different types of treatments were used: simultaneous incubation of cells with individual test compounds and the toxicant; pre-treatment with test compound before addition of the toxicant followed or not by a recovery period. The expression of Hsp70 was quantified by Western blotting to test the involvement of heat shock proteins in the cellular responses to the test compounds. In addition, effects on proliferation were evaluated by the MTT assay. The results show that quercetin and ursolic acid prevented DNA damage and had antiproliferative properties in HepG2 cells suggesting an anticarcinogenic potential for these compounds. The protective effects of quercetin against t-BHP-induced DNA damage seem to be due to both direct effects on t-BHP toxicity and to cellularly mediated indirect effects which reflect the potentiation of the cellular antioxidant defenses. Ursolic acid seems to exert effects only through cellularly mediated mechanisms since it was not protective in simultaneous incubation. Quercetin and ursolic acid also showed to increase the rate of DNA repair. Rutin did not have effects at any level. These results, obtained with liver cells, emphasize and confirm the chemopreventive potential of quercetin and ursolic acid, which may help explain the lower cancer incidence in human population with high dietary intakes of fruits and vegetables. These results also demonstrate that Hsp70 is not involved in the observed effects in HepG2.
Asunto(s)
Antimutagênicos/farmacología , Antioxidantes/farmacología , Hepatocitos/efectos de los fármacos , Quercetina/farmacología , Rutina/farmacología , Triterpenos/farmacología , Carcinoma Hepatocelular , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Ensayo Cometa , Daño del ADN/efectos de los fármacos , Reparación del ADN/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Antagonismo de Drogas , Combinación de Medicamentos , Formazáns/metabolismo , Proteínas HSP70 de Choque Térmico/metabolismo , Hepatocitos/metabolismo , Humanos , Sales de Tetrazolio/metabolismo , Ácido UrsólicoRESUMEN
The possibility of reducing morbidity associated with surgical dissection while maintaining accurate tumor staging is one of the greatest advantages of the sentinel node approach in surgical oncology. The sentinel node mapping has already proven to be useful in melanoma, breast cancer, and vulvar cancer. We report the first case of sentinel node detection by technetium-labeled radiocolloid in a pregnant woman with cervical cancer. The histologic analysis of the operative specimen showed a poorly differentiated squamous carcinoma with metastasis in the sentinel node and a neoplasic embolus in a blood vessel of the placental bed. The lymphatic mapping and sentinel lymph node detection are feasible during pregnancy.
Asunto(s)
Carcinoma de Células Escamosas/diagnóstico , Complicaciones Neoplásicas del Embarazo/diagnóstico , Biopsia del Ganglio Linfático Centinela , Neoplasias del Cuello Uterino/diagnóstico , Aborto Eugénico/métodos , Adulto , Carcinoma de Células Escamosas/cirugía , Femenino , Humanos , Cuidados Intraoperatorios , Embarazo , Azufre Coloidal Tecnecio Tc 99m , Neoplasias del Cuello Uterino/cirugíaRESUMEN
For this study the essential oil (EO) of sage (Salvia officinalis L.) was isolated from air-dried vegetative aerial parts of the plants by hydrodistillation and analysed by GC and GC-MS. A total yield of 12.07 mg of EO per g of plant dry mass was obtained and more than 50 compounds identified. The major compounds were cis-thujone (17.4%), alpha-humulene (13.3%), 1,8-cineole (12.7%), E-caryophyllene (8.5%) and borneol (8.3%). The EO fraction of sage tea was also isolated by partition with pentane and the respective components identified. The toxic and antioxidant protective effects of S. officinalis EO were evaluated on freshly isolated rat hepatocytes. Cell viability (LDH leakage), lipid peroxidation and glutathione status were measured in experiments undertaken with cells (suspensions of 1 x 10(6) cells per millilitre) exposed to EO alone (toxicity of the EO;t-BHP as positive control); and with cells exposed to EO and an oxidative compound (t-BHP) together (in EO protection evaluation; quercetin as positive control) for 30 min. The results show that the EO is not toxic when present at concentrations below 200 nl/ml; it was only at 2000 nl EO/ml that a significant LDH leakage and GSH decrease were observed indicating cell damage. In the range of concentrations tested, the EO did not show protective effects against t-BHP-induced toxicity.