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1.
Foods ; 13(9)2024 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-38731724

RESUMEN

This study aimed to evaluate the influence of films based on chitosan and rosemary extract on the physicochemical, microbiological, and oxidative characteristics of beef. Refrigerated steaks of Longissimus dorsi were distributed in a factorial arrangement (4 × 4) into four treatments consisting of four edible films (control; chitosan; chitosan + 4% rosemary extract; and chitosan + 8% rosemary extract) and four days of aging (0, 2, 4, and 8 days). Incorporating 4% or 8% rosemary extract into the chitosan film improved the characteristics of the films in terms of moisture absorption and elasticity. The edible coatings with chitosan and rosemary extract and the different days of aging increased the tenderness and decreased the lipid oxidation of beef. In addition, the chitosan films containing rosemary extract increased the water-holding capacity and decreased the cooking losses of beef. The films containing 4% and 8% rosemary extract decreased the development of mesophilic and psychrotrophic bacteria and Staphylococcus ssp. in beef. We recommend incorporating 4% rosemary extract into chitosan-based coatings to preserve the quality of refrigerated beef.

2.
Ultramicroscopy ; 209: 112862, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31707231

RESUMEN

Atomic force microscopy (AFM) was used in this work to investigate the ultrastructural and mechanical characteristics of Haemonchus contortus, the major gastrointestinal nematode that infects small ruminants worldwide. The biophysical characterization of this species is extremely important in order to reveal mechanisms of action of drugs and to classify its ultrastructure and biomechanical properties. High-resolution topographic images by AFM as well as data on biomechanical properties of cuticles were obtained at different stages of H. contortus. The results reveal details of the mechanical and structural properties of this nematode never observed before for nematodes parasite with other microscope techniques. Qualitative and quantitative reductions in the elasticity of the larvae stage egg were compared with those of the morulae stage, and the increased adhesion of unsheathed L3 were compared with the same stage of sheathed larvae. The results presented here open possibilities for understanding the mechanisms of drug and biomolecular actions that can be used to control infections caused by H. contortus.


Asunto(s)
Haemonchus/ultraestructura , Microscopía de Fuerza Atómica/métodos , Animales , Fenómenos Biomecánicos , Biofisica , Femenino , Haemonchus/crecimiento & desarrollo , Larva , Estadios del Ciclo de Vida , Ovinos
3.
Drug Deliv ; 25(1): 1585-1594, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30044149

RESUMEN

Voriconazole (VCZ), a triazole with a large spectrum of action is one of the most recommended antifungal agents as the first line therapy against several clinically important systemic fungal infections, including those by Candida albicans. This antifungal has moderate water solubility and exhibits a nonlinear pharmacokinetic (PK) profile. By entrapping VCZ into liposomes, it is possible to circumvent certain downsides of the currently available product such as a reduction in the rate of its metabolization into an inactive form, avoidance of the toxicity of the sulfobutyl ether-beta-cyclodextrin (SBECD), vehicle used to increase its solubility. PKs and biodistribution of VCZ modified by encapsulation into liposomes resulted in improved antifungal activity, due to increased specificity and tissue penetration. In this work, liposomal VCZ resulted in AUC0-24/MIC ratio of 53.51 ± 11.12, whereas VFEND® resulted in a 2.5-fold lower AUC0-24/MIC ratio (21.51 ± 2.88), indicating favorable antimicrobial systemic activity. VCZ accumulation in the liver and kidneys was significantly higher when the liposomal form was used. Protection of the drug from biological degradation and reduced rate of metabolism leads to a 30% reduction of AUC of the inactive metabolite voriconazole-N-oxide (VNO) when the liposomal drug was administered. Liposomal VCZ presents an alternative therapeutic platform, leading to a safe and effective treatment against systemic fungal infections.


Asunto(s)
Antifúngicos/administración & dosificación , Antifúngicos/farmacocinética , Sistemas de Liberación de Medicamentos/métodos , Voriconazol/administración & dosificación , Voriconazol/farmacocinética , Administración Intravenosa , Animales , Antifúngicos/química , Aspergillus/efectos de los fármacos , Aspergillus/fisiología , Candida albicans/efectos de los fármacos , Candida albicans/fisiología , Candidiasis/tratamiento farmacológico , Candidiasis/metabolismo , Composición de Medicamentos , Humanos , Liposomas , Masculino , Ratones Endogámicos BALB C , Pruebas de Sensibilidad Microbiana/métodos , Distribución Tisular/efectos de los fármacos , Distribución Tisular/fisiología , Voriconazol/química
4.
Mycoses ; 60(1): 59-65, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27625302

RESUMEN

Histoplasmosis is a systemic mycosis that is considered an important public health problem. In this work, we performed a descriptive, observational, cross-sectional and retrospective study with a secondary data analysis of medical records from 2000 to 2012 at a tertiary hospital. The study sample consisted of 275 patients with laboratory-confirmed Disseminated Histoplasmosis (DH)/AIDS. The results showed that the prevalence of DH associated with AIDS was 4.4%. The majority of patients were young adult men with fever in 84.2%, cough in 63.4%, weight loss in 63.1%, diarrhoea in 44.8% and skin manifestations in 27.6% of patients. In the overall cohort, the CD4 counts were low, but not significantly different in survivors and non-survivors. Higher levels of urea and lower levels of haemoglobin and platelets were observed in non-survivor patients (<.05). The global lethality was 71.3% (196/275). The results with high prevalence and lethality highlight the need to adopt measures to facilitate early diagnosis, proper treatment and improved prognosis.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/complicaciones , Histoplasmosis/epidemiología , Infecciones Oportunistas/epidemiología , Síndrome de Inmunodeficiencia Adquirida/epidemiología , Síndrome de Inmunodeficiencia Adquirida/mortalidad , Adolescente , Adulto , Anciano , Antifúngicos/uso terapéutico , Brasil/epidemiología , Recuento de Linfocito CD4 , Niño , Estudios de Cohortes , Estudios Transversales , Femenino , Hemoglobinas/análisis , Histoplasmosis/tratamiento farmacológico , Histoplasmosis/mortalidad , Humanos , Masculino , Registros Médicos , Persona de Mediana Edad , Infecciones Oportunistas/tratamiento farmacológico , Infecciones Oportunistas/mortalidad , Recuento de Plaquetas , Prevalencia , Estudios Retrospectivos , Centros de Atención Terciaria/estadística & datos numéricos , Urea/análisis , Adulto Joven
5.
Int J Biol Markers ; 31(1): e38-43, 2016 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-26349667

RESUMEN

PURPOSE: The use of trastuzumab (Herceptin) to target HER2 has been applied in breast carcinoma and gastric carcinoma (GC). Previous studies have tested trastuzumab's effectiveness by assessing HER2 expression or HER2 amplification by means of immunohistochemistry (IHC) or fluorescence in situ hybridization (FISH). In this work we aimed to evaluate automated FISH and IHC technologies for HER2 detection in GC biopsies to be used in routine pathology practice. METHODS: The study used an Oracle HER2 IHC System and an LSI HER2/CEP17 Dual Probe on an automated Bond system (Leica Microsystems). One hundred GC biopsies were evaluated including 44 intestinal type, 38 diffuse type and 18 indeterminate type according to Lauren's classification. RESULTS: The overall concordance rate between the automated FISH and IHC methods was 94% (κ = 0.87), as 6 samples were scored as equivocal (4 in IHC and 2 in FISH). Moreover, HER2 positivity was significantly different between the 3 types of GC (p<0.05), being more frequent in intestinal-type GC (23%) than in the other 2 histological types (5% and 0%). Finally, the HER2/CEP17 FISH ratio was significantly different (p<0.01) between disomic and polysomic samples, being higher in polysomic samples (mean 1.633 ± 0.509) than in disomic samples (mean 1.231 ± 0.675). CONCLUSIONS: Automated HER2 testing of GC biopsies using the Leica Bond system was useful and efficient. This method allowed us to improve normal routine procedures, minimizing time and costs as well as handling and observation errors.


Asunto(s)
Biomarcadores de Tumor/biosíntesis , Carcinoma/diagnóstico , Receptor ErbB-2/biosíntesis , Neoplasias Gástricas/diagnóstico , Biomarcadores de Tumor/genética , Biopsia , Carcinoma/genética , Carcinoma/patología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Inmunohistoquímica , Hibridación Fluorescente in Situ , Receptor ErbB-2/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/patología , Trastuzumab/uso terapéutico
6.
Biomed Res Int ; 2014: 305239, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24812611

RESUMEN

At present, noncoding small RNAs are recognized as key players in novel forms of posttranscriptional gene regulation in most eukaryotes. However, canonical small RNA pathways seem to be lost or excessively simplified in some unicellular organisms including Trypanosoma cruzi which lack functional RNAi pathways. Recently, we reported the presence of alternate small RNA pathways in T. cruzi mainly represented by homogeneous populations of tRNA- and rRNA-derived small RNAs, which are secreted to the extracellular medium included in extracellular vesicles. Extracellular vesicle cargo could be delivered to other parasites and to mammalian susceptible cells promoting metacyclogenesis and conferring susceptibility to infection, respectively. Here we analyzed the changes in gene expression of host HeLa cells induced by extracellular vesicles from T. cruzi. As assessed by microarray assays a large set of genes in HeLa cells were differentially expressed upon incorporation of T. cruzi-derived extracellular vesicles. The elicited response modified mainly host cell cytoskeleton, extracellular matrix, and immune responses pathways. Some genes were also modified by the most abundant tRNA-derived small RNAs included in extracellular vesicles. These data suggest that microvesicles secreted by T. cruzi could be relevant players in early events of the T. cruzi host cell interplay.


Asunto(s)
Vesículas Citoplasmáticas/metabolismo , Regulación de la Expresión Génica , Interacciones Huésped-Parásitos , Mamíferos/parasitología , ARN de Transferencia/metabolismo , Trypanosoma cruzi/genética , Animales , Citoesqueleto/metabolismo , Matriz Extracelular/genética , Espacio Extracelular/metabolismo , Perfilación de la Expresión Génica , Células HeLa , Humanos , Inmunidad/genética , Cinética , Análisis de Secuencia por Matrices de Oligonucleótidos , Factores de Tiempo , Transfección
7.
Parasitol Res ; 113(1): 285-304, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24241124

RESUMEN

The protozoan parasite Trypanosoma cruzi has a complex life cycle characterized by intracellular and extracellular forms alternating between invertebrate and mammals. To cope with these changing environments, T. cruzi undergoes rapid changes in gene expression, which are achieved essentially at the posttranscriptional level. At present, expanding families of small RNAs are recognized as key players in novel forms of posttranscriptional gene regulation in most eukaryotes. However, T. cruzi lacks canonical small RNA pathways. In a recent work, we reported the presence of alternate small RNA pathways in T. cruzi mainly represented by a homogeneous population of tRNA-derived small RNAs (tsRNAs). In T. cruzi epimastigotes submitted to nutrient starvation, tsRNAs colocalized with an argonaute protein distinctive of trypanosomatids (TcPIWI-tryp) and were recruited to particular cytoplasmic granules. Using epifluorescence and electronic microscopy, we observed that tsRNAs and the TcPIWI-tryp protein were recruited mainly to reservosomes and other intracellular vesicles including endosome-like vesicles and vesicular structures resembling the Golgi complex. These data suggested that, in T. cruzi, tsRNA biogenesis is probably part of endocytic/exocytic routes. We also demonstrated that epimastigotes submitted to nutrient starvation shed high levels of vesicles to the extracellular medium, which carry small tRNAs and TcPIWI-tryp proteins as cargo. At least a fraction of extracellular vesicle cargo was transferred between parasites and to mammalian susceptible cells. Our data afford experimental evidence, indicating that extracellular vesicles shed by T. cruzi promote not only life cycle transition of epimastigotes to trypomastigote forms but also infection susceptibility of mammalian cells.


Asunto(s)
Vesículas Citoplasmáticas/parasitología , Estadios del Ciclo de Vida/fisiología , ARN Protozoario/metabolismo , Trypanosoma cruzi/fisiología , Animales , Chlorocebus aethiops , Endosomas/parasitología , Aparato de Golgi/parasitología , Humanos , Células K562 , Microscopía Electrónica de Transmisión , ARN de Transferencia/metabolismo , Trypanosoma cruzi/genética , Trypanosoma cruzi/ultraestructura , Células Vero
8.
Biopolymers ; 98(4): 322-31, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23193596

RESUMEN

The antimicrobial peptides (AMPs) are evolutionarily ancient molecules that act as components of the innate immune system. Recently, it was demonstrated that a single AMP can perform various functions; this ability is known as "peptide promiscuity." However, little is known about promiscuity in plant AMPs without disulfide bonds. This study was carried out to evaluate the promiscuity of Cn-AMP1: a promising disulfide-free plant peptide with reduced size and cationic and hydrophobic properties. Its activity against human pathogenic bacteria and fungal pathogens, as well as its in vitro immunostimulatory activity and effects on cancerous and healthy mammalian cell proliferation were studied here. Cn-AMP1 exerts antimicrobial effects against Gram-positive bacteria, Gram-negative bacteria, and fungi. Moreover, tumor cell viability activity in Caco-2 cells, as well as immunostimulatory activity by evaluating upregulated inflammatory-cytokine secretion by monocytes was also positively observed. Cn-AMP1 does not exhibit a well-defined conformation in aqueous solution and probably undergoes a 3(10)-helix transition in hydrophobic environments. The experimental results support the promiscuous activity of Cn-AMP1, presenting a wide range of activities, including antibacterial, antifungal, and immunostimulatory activity. In the future, Cn-AMP1 should be used in the development of novel biopharmaceuticals, mainly due to its reduced size and broad spectrum of activity.


Asunto(s)
Antiinfecciosos/farmacología , Péptidos/farmacología , Adyuvantes Inmunológicos/química , Adyuvantes Inmunológicos/farmacología , Animales , Antibacterianos/química , Antibacterianos/farmacología , Antiinfecciosos/química , Antifúngicos/química , Antifúngicos/farmacología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Humanos , Péptidos/química
9.
PLoS One ; 7(10): e47047, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23056574

RESUMEN

Recently, defense peptides that are able to act against several targets have been characterized. The present work focuses on structural and functional evaluation of the peptide analogue Pa-MAP, previously isolated as an antifreeze peptide from Pleuronectes americanus. Pa-MAP showed activities against different targets such as tumoral cells in culture (CACO-2, MCF-7 and HCT-116), bacteria (Escherichia coli ATCC 8739 and Staphylococcus aureus ATCC 25923), viruses (HSV-1 and HSV-2) and fungi (Candida parapsilosis ATCC 22019, Trichophyton mentagrophytes (28d&E) and T. rubrum (327)). This peptide did not show toxicity against mammalian cells such as erythrocytes, Vero and RAW 264.7 cells. Molecular mechanism of action was related to hydrophobic residues, since only the terminal amino group is charged at pH 7 as confirmed by potentiometric titration. In order to shed some light on its structure-function relations, in vitro and in silico assays were carried out using circular dichroism and molecular dynamics. Furthermore, Pa-MAP showed partial unfolding of the peptide changes in a wide pH (3 to 11) and temperature (25 to 95°C) ranges, although it might not reach complete unfolding at 95°C, suggesting a high conformational stability. This peptide also showed a conformational transition with a partial α-helical fold in water and a full α-helical core in SDS and TFE environments. These results were corroborated by spectral data measured at 222 nm and by 50 ns dynamic simulation. In conclusion, data reported here show that Pa-MAP is a potential candidate for drug design against pathogenic microorganisms due to its structural stability and wide activity against a range of targets.


Asunto(s)
Alanina/química , Lenguado/metabolismo , Péptidos/química , Péptidos/farmacología , Animales , Células CACO-2 , Candida/efectos de los fármacos , Línea Celular , Eritrocitos/efectos de los fármacos , Células HCT116 , Humanos , Staphylococcus aureus/efectos de los fármacos , Trichophyton/efectos de los fármacos
10.
Biochimie ; 94(4): 968-74, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22210491

RESUMEN

Antimicrobial peptides have been found in mollusks and other sea animals. In this report, a crude extract of the marine snail Cenchritis muricatus was evaluated against human pathogens responsible for multiple deleterious effects and diseases. A peptide of 1485.26 Da was purified by reversed-phase HPLC and functionally characterized. This trypsinized peptide was sequenced by MS/MS technology, and a sequence (SRSELIVHQR), named Cm-p1 was recovered, chemically synthesized and functionally characterized. This peptide demonstrated the capacity to prevent the development of yeasts and filamentous fungi. Otherwise, Cm-p1 displayed no toxic effects against mammalian cells. Molecular modeling analyses showed that this peptide possible forms a single hydrophilic α-helix and the probable cationic residue involved in antifungal activity action is proposed. The data reported here demonstrate the importance of sea animals peptide discovery for biotechnological tools development that could be useful in solving human health and agribusiness problems.


Asunto(s)
Antifúngicos/aislamiento & purificación , Fragmentos de Péptidos/aislamiento & purificación , Secuencia de Aminoácidos , Animales , Antifúngicos/química , Antifúngicos/farmacología , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Cromatografía de Fase Inversa , Eritrocitos , Hongos/efectos de los fármacos , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Ratones , Pruebas de Sensibilidad Microbiana , Modelos Moleculares , Datos de Secuencia Molecular , Fragmentos de Péptidos/química , Fragmentos de Péptidos/farmacología , Estructura Secundaria de Proteína , Análisis de Secuencia de Proteína , Caracoles , Propiedades de Superficie
11.
Phytochemistry ; 74: 166-72, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22137037

RESUMEN

A phytochemical study of the ethyl acetate extract of the roots and adventitious roots of Spirotropis longifolia, a monodominant tree species of the Guianan rainforest, has allowed the isolation of three compounds: 2-hydroxy-8,9-methylenedioxy-2',2'-dimethylpyrano-[5',6':4,3]-6a-prenyl-[6aS,11aS]-pterocarpan (spirotropin A), 2-hydroxy-8,9-methylenedioxy-2',2'-dimethyl-3',4'-dihydropyrano-[5',6':4,3]-6a-prenyl-[6aS,11aS]-pterocarpan (spirotropin B), and 5,7-dihydroxy-6,8-diprenyl-2'''',2''''-dimethylpyrano[5'''',6'''': 3',4']-isoflavone (spirotropone). In addition, 10 known compounds, trans-oxyresveratrol, trans-resveratrol, piceatannol, daidzein, genistein, isoprunetin, lupeol, latifolol, gnetin D and gnetin E, were also isolated. These compounds were evaluated for their antifungal activity and their cytotoxicity, and their structures were established by 1D and 2D NMR, HRMS, CD and optical rotation measurements.


Asunto(s)
Antifúngicos/farmacología , Fabaceae/química , Hongos/efectos de los fármacos , Isoflavonas/farmacología , Extractos Vegetales/farmacología , Antifúngicos/química , Antifúngicos/aislamiento & purificación , Fabaceae/metabolismo , Humanos , Isoflavonas/química , Isoflavonas/aislamiento & purificación , Estructura Molecular , Extractos Vegetales/química , Raíces de Plantas
12.
Clinics (Sao Paulo) ; 66(8): 1335-40, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21915480

RESUMEN

OBJECTIVE: To evaluate the outcomes of acute myeloid leukemia patients who were older than 60 years of age at the time of diagnosis following the implementation of a treatment algorithm based on age, performance status, and cytogenetic results. METHODS: We retrospectively compared the results of 31 elderly acute myeloid leukemia patients (median age of 74 years) who were treated according to the new algorithm. RESULTS: Fifteen patients with a good performance status and no unfavorable karyotypes were treated with either intensive cytotoxic chemotherapy (<70 years, nine cases) or adapted etoposide, 6-thioguanine and idarubicine (>70 years, six cases); 16 cases with a poor performance status or unfavorable cytogenetics received supportive care only. Six patients achieved a complete remission and two achieved a partial remission after chemotherapy. There were three toxic deaths during induction, two in the adapted etoposide, 6-thioguanine and idarubicine group and one in the intensive cytotoxic chemotherapy group. The overall median survival time was 2.96 months, 1.3 months in the supportive care group, and 4.6 months in the treatment group. CONCLUSIONS: Our results illustrate the importance of treatment guidelines adapted to local resources in an attempt to improve the survival of elderly acute myeloid leukemia patients in developing countries.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Leucemia Mieloide Aguda/tratamiento farmacológico , Anciano , Anciano de 80 o más Años , Algoritmos , Brasil , Análisis Citogenético , Etopósido/administración & dosificación , Femenino , Hospitales Universitarios , Humanos , Idarrubicina/administración & dosificación , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/mortalidad , Masculino , Persona de Mediana Edad , Cuidados Paliativos , Pronóstico , Estudios Retrospectivos , Tioguanina/administración & dosificación , Resultado del Tratamiento
13.
Clinics ; 66(8): 1335-1340, 2011.
Artículo en Inglés | LILACS | ID: lil-598372

RESUMEN

OBJECTIVE: To evaluate the outcomes of acute myeloid leukemia patients who were older than 60 years of age at the time of diagnosis following the implementation of a treatment algorithm based on age, performance status, and cytogenetic results. METHODS: We retrospectively compared the results of 31 elderly acute myeloid leukemia patients (median age of 74 years) who were treated according to the new algorithm. RESULTS: Fifteen patients with a good performance status and no unfavorable karyotypes were treated with either intensive cytotoxic chemotherapy (<70 years, nine cases) or adapted etoposide, 6-thioguanine and idarubicine (>70 years, six cases); 16 cases with a poor performance status or unfavorable cytogenetics received supportive care only. Six patients achieved a complete remission and two achieved a partial remission after chemotherapy. There were three toxic deaths during induction, two in the adapted etoposide, 6-thioguanine and idarubicine group and one in the intensive cytotoxic chemotherapy group. The overall median survival time was 2.96 months, 1.3 months in the supportive care group, and 4.6 months in the treatment group. CONCLUSIONS: Our results illustrate the importance of treatment guidelines adapted to local resources in an attempt to improve the survival of elderly acute myeloid leukemia patients in developing countries.


Asunto(s)
Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Leucemia Mieloide Aguda/tratamiento farmacológico , Algoritmos , Brasil , Análisis Citogenético , Etopósido/administración & dosificación , Hospitales Universitarios , Idarrubicina/administración & dosificación , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/mortalidad , Cuidados Paliativos , Pronóstico , Estudios Retrospectivos , Resultado del Tratamiento , Tioguanina/administración & dosificación
14.
J Nat Prod ; 73(10): 1706-7, 2010 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-20886871

RESUMEN

Research on antifungal compounds from the durable wood from French Guiana Amazonian forest trees highlights the correlation between the activity of their extracts against wood-rotting fungi and human pathogens. The fractionation of an ethyl acetate extract of Sextonia rubra wood led to the isolation of rubrenolide (1) and rubrynolide (2). The potential of compounds 1 and 2 is described through the evaluation of their activity against 16 pathogenic fungi and their cytotoxicity toward NIH-3T3 mammalian fibroblast cells.


Asunto(s)
Acetales/aislamiento & purificación , Acetales/farmacología , Alquenos/aislamiento & purificación , Alquenos/farmacología , Alquinos/aislamiento & purificación , Alquinos/farmacología , Antifúngicos/aislamiento & purificación , Antifúngicos/farmacología , Basidiomycota/química , Polyporaceae/química , Árboles/microbiología , Acetales/química , Alquenos/química , Alquinos/química , Animales , Antifúngicos/química , Guyana Francesa , Lauraceae/microbiología , Ratones , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Células 3T3 NIH , Tallos de la Planta/química , Madera/microbiología
15.
Gene ; 466(1-2): 26-35, 2010 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-20621168

RESUMEN

Over the last years an expanding family of small non-coding RNAs (sRNA) has been identified in eukaryotic genomes which behave as sequence-specific triggers for mRNA degradation, translation repression, heterochromatin formation and genome stability. To achieve their effectors functions, sRNAs associate with members of the Argonaute protein family. Argonaute proteins are segregated into three paralogous groups: the AGO-like subfamily, the PIWI-like subfamily, and the WAGO subfamily (for Worm specific AGO). Detailed phylogenetic analysis of the small RNA-related machinery components revealed that they can be traced back to the common ancestor of eukaryotes. However, this machinery seems to be lost or excessively simplified in some unicellular organisms such as Saccharomyces cerevisiae, Trypanosoma cruzi, Leishmania major and Plasmodium falciparum which are unable to utilize dsRNA to trigger degradation of target RNAs. We reported here a unique ORF encoding for an AGO/PIWI protein in T. cruzi which was expressed in all stages of its life cycle at the transcript as well as the protein level. Database search for remote homologues, revealed the presence of a divergent PAZ domain adjacent to the well supported PIWI domain. Our results strongly suggested that this unique AGO/PIWI protein from T. cruzi is a canonical Argonaute in terms of its domain architecture. We propose to reclassify all Argonaute members from trypanosomatids as a distinctive phylogenetic group representing a new subfamily of Argonaute proteins and propose the generic designation of AGO/PIWI-tryp to identify them. Inside the Trypanosomatid-specific node, AGO/PIWI-tryps were clearly segregated into two paralog groups designated as AGO-tryp and PIWI-tryp according to the presence or absence of a functional link with RNAi-related phenomena, respectively.


Asunto(s)
Proteínas Protozoarias/análisis , Trypanosoma cruzi/clasificación , Trypanosoma cruzi/metabolismo , Secuencia de Aminoácidos , Animales , Clonación Molecular , Evolución Molecular , Modelos Moleculares , Datos de Secuencia Molecular , Filogenia , Proteínas Protozoarias/química , ARN Interferente Pequeño , Homología de Secuencia de Ácido Nucleico
16.
Anal Bioanal Chem ; 387(6): 2245-53, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17260139

RESUMEN

The use of a copper solid amalgam electrode (CuSAE) for the analytical determination of triazine herbicides (atrazine and ametryne) instead of the conventional hanging mercury drop electrode (HMDE) is reported. The results obtained using electroanalytical methods utilizing each of these electrodes were also compared with those provided by the HPLC technique. The results indicated that the CuSAE electrode can be used to detect the herbicides studied, since the detection limits reached using the electrode (3.06 microg L-1 and 3.78 microg L-1 for atrazine and ametryne, respectively) are lower than the maximum values permitted by CONAMA (Brazilian National Council for the Environment) for wastewaters (50 microg L-1) and by the US EPA (Environmental Protection Agency of the United States) in natural water samples (10.00 microg L-1). An electroanalytical methodology employing CuSAE and square wave voltammetry (SWV) was successfully applied to the determination of atrazine and ametryne in natural water samples, yielding good recoveries (70.30%-79.40%). This indicates that the CuSAE provides a convenient substitute for the HMDE, particularly since the CuSAE minimizes the toxic waste residues produced by the use of mercury in HDME-based analyses.


Asunto(s)
Aleaciones , Cromatografía Líquida de Alta Presión/métodos , Herbicidas/análisis , Eliminación de Residuos/métodos , Triazinas/análisis , Electrodos , Mercurio
17.
Leuk Res ; 27(4): 363-6, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12531229

RESUMEN

We present a case of acute myeloid leukemia with t(4;12). This translocation is rare and has been observed in acute leukemias with different but immature phenotypes. To the best of our knowledge, there are around 15 descriptions of t(4;12) in AML, and most interesting, presenting morphological aspects of a pseudo-lymphoid cell with dysplasia of other series.


Asunto(s)
Cromosomas Humanos Par 12 , Cromosomas Humanos Par 4 , Leucemia Mieloide/genética , Translocación Genética , Enfermedad Aguda , Adulto , Análisis Citogenético , Resultado Fatal , Humanos , Inmunofenotipificación , Leucemia Mieloide/patología , Leucemia Mieloide/terapia , Masculino
18.
Cell Transplant ; 11(6): 583-92, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12428748

RESUMEN

Vascular smooth muscle cells (VSMC) are ideal for systemic gene therapy because of their proximity to blood vessels and they have demonstrated long-term exogenous gene expression in vivo. However, the procedure generally followed to seed the transduced VSMC onto arteries denuded of endothelial cells usually induces stenosis and thrombosis, with a consequent high risk for use in humans. We demonstrate here that the vascular adventitia is a suitable place to introduce transduced VSMC and to secrete therapeutic proteins into the blood stream by a simple procedure, avoiding postoperative vascular complications. Transduced VSMC, with the retroviral vectors carrying the human growth hormone gene (hGH), were seeded into the adventitia of the rat abdominal aorta by single injection of a cell suspension. Based on the hGH and anti-hGH production in serum and on histological analysis of the removed aortas, we demonstrated hGH production over the 2-month experimental period. None of the animals used in the experiment showed stenosis, thrombosis, or other vascular or visible physiological abnormalities.


Asunto(s)
Trasplante de Células/métodos , Endotelio Vascular/citología , Expresión Génica , Músculo Liso Vascular/trasplante , Células 3T3 , Animales , Aorta Abdominal , Células Cultivadas , ADN Complementario/genética , Endotelio Vascular/fisiología , Terapia Genética/métodos , Vectores Genéticos , Hormona de Crecimiento Humana/sangre , Hormona de Crecimiento Humana/genética , Humanos , Cinética , Ratones , Músculo Liso Vascular/citología , Regiones Promotoras Genéticas , Ratas , Ratas Wistar , Retroviridae , Secuencias Repetidas Terminales , Transfección/métodos , Zinc/farmacología
19.
Rev. bras. hematol. hemoter ; 23(2): 63-68, maio-ago. 2001. graf
Artículo en Inglés | LILACS | ID: lil-338272

RESUMEN

Bone marrow biopsy allows evaluation of cellularity, abnormal localization of immature precursors and fibrosis in myelodysplastic syndrome. It has been considered important to make diagnosis and prognosis of this disorder. The object of this study evaluated the influence of histopathological parameters, such as cellularity, erythroid/myeloid ratio, abnormal localization of immature precursors and marrow fibrosis, on survival of myelodysplastic syndrome patients. Forty-six patients, admitted from April 1985 to June 1998, and diagnosed as being myelodysplastic syndrome according to French-American-British criteria, were selected. There were 20 males and 26 females, with median age of 61 years. Forty-six bone marrow smears and 36 trephine biopsies were reviewed. Mean survival of hypocellular cases was 64.8 months and of hyper and normocellular cases was 31.8 months. Patients with predominance of erythroid hyperplasia had mean survival of 50.8 months, greater than those with predominance of myeloid hyperplasia (20.3 months). There was no statistical difference in survival of patients with or without abnormal localization of immature precursors and with or without marrow fibrosis. Bone marrow biopsy is a useful tool for the identification of parameters that influence prognosis in myelodysplastic syndrome. Hypocellularity and erythroid hyperplasia were correlated with longer survival while myeloid hyperplasia with poorer survival


A biópsia de medula óssea propicia a avaliação da celularidade global, dos precursores imaturos de localização anormal e de fibrose nas sídromes mielodisplásicas. O método tem sido considerado importante também para o diagnóstico e prognóstico da síndrome. O objetivo deste estudo foi o de o observar a influência de parâmetros histológicos como a celularidade, a relação eritróide mielóide, a presença de precursores imaturos de localização anormal e fibrose medular na sobrevida de pacients com a síndrome. De abril de 1985 a junho de 1998, 46 pacientes diagnosticados segundo os critérios do grupo Franco, Americano, Britânico foram estudados. A casuística era composta de 20 pacientes do sexo masculino e de 26 do sexo feminino com idade média de 61 anos. Foram revisados 46 esfregaços de aspirado de medula óssea e 36 cortes histológicos de bioópsia de medula óssea. A sobrevida média dos casos de hipocelularidade foi de 64,8 meses e dos casos que eram hiper ou normocelulares foi de 31,8 meses. Pacientes com a predominância de hiperplasia tiveram sobrevida média de 50,8 meses, que foi superior aos que apresentavam hiperplasia mielóide (20,3 meses). Não houve diferença estatística na sobrevida dos pacientes que apresentaram ou não fibrose medular. A biópsia de medula óssea deve ser considerada útil na identificação de prâmetros que influenciam no prognóstico da síndrome mielodisplásica. A hipocelularidade e a hiperplasia eritrocitária está realcionada com a sobrevida maior, enquanto a hiperplasia mielóide com a sobrevida mais curta.


Asunto(s)
Humanos , Masculino , Femenino , Persona de Mediana Edad , Biopsia , Médula Ósea , Técnicas de Laboratorio Clínico , Síndromes Mielodisplásicos , Pronóstico , Síndromes Mielodisplásicos/patología
20.
Medicina (Ribeiräo Preto) ; 33(3): 331-7, jul.-set. 2000. tab
Artículo en Portugués | LILACS | ID: lil-283069

RESUMEN

Modelo do estudo: observacional retrospectivo. Objetivo: conhecer a freqüência das alteraçöes oculopalpebrais em pacientes atendidos na Faculdade de Medicina de Botucatu, Säo Paulo. Método: o estudo foi realizado através da análise de fichas de atendimento no Serviço de Plástica Ocular da Faculdade de Medicina de Botucatu, durante o período de 12 anos, avaliando-se a idade, sexo, procedência e diagnóstico principal dos pacientes atendidos. Resultado: no período estudado foram avaliados 3323 pacientes, 58,3 por cento dos indivíduos eram procedentes da regiäo de Botucatu; a faixa etária superior a 60 anos (41,6 por cento) e o sexo feminino foram os prevalentes (55,7 por cento) e as patologias com alteraçäo da posiçäo palpebral foram as mais comuns. Comentários: as alteraçöes mais freqüêntes foram as relacionadas com a posiçäo das pálpebras e as lesöes benignas; o conhecimento da freqüência das alteraçöes oculopalpebrais é importante para a adoçäo de medidas preventivas e para planejar o treinamento de novos profissionais.


Asunto(s)
Humanos , Masculino , Femenino , Niño , Adolescente , Adulto , Persona de Mediana Edad , Lesiones Oculares/epidemiología , Enfermedades de los Párpados , Cilios , Facultades de Medicina , Neoplasias del Ojo
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