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1.
Genet Mol Res ; 12(2): 1752-60, 2013 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-23765981

RESUMEN

An estuary is a transition zone between freshwater and marine ecosystems, resulting in dilution of seawater. Estuaries are also considered environments of intense biological activity related to the processes of nutrient cycling. The aim of this study was to evaluate the microbial community composition along a salinity gradient in the estuary of the Cachoeira River, located in southern Bahia, Brazil. The analysis of bacterial and yeast communities was performed by determining the denaturing gradient gel electrophoresis band richness. Formation of zones with similar profiles of bands was observed, and the increasing richness at the intermediate zone demonstrated a clear spatial distinction of communities depending on salinity. In addition, the dissolved oxygen content, temperature, pH, salinity, and dissolved inorganic nutrient contents (NH3(+), NO2(-), NO3(-), PO4(-)) were determined. Nutrients were distributed in similar patterns, with decreasing concentrations as the salinity increases.


Asunto(s)
Bacterias/genética , Electroforesis en Gel de Gradiente Desnaturalizante , Estuarios , Ríos/microbiología , Salinidad , Levaduras/genética , Brasil , Variación Genética , Geografía , Análisis de Componente Principal
2.
J Hosp Infect ; 83(3): 200-4, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23374287

RESUMEN

BACKGROUND: The increase in opportunistic fungal infections has led to the search for putative sources of contamination in hospital environments. AIM: Ants in a public hospital in Itabuna, north-eastern Brazil were examined for carriage of filamentous fungi. METHODS: During a year-long survey, ants from different hospital areas were sampled. Preference was given to locations where it was possible to observe ants actively foraging. The fungi found on the ants' integument were cultured and identified. FINDINGS: A total of 106 ant workers belonging to 12 species in 11 genera were collected. A total of 47 fungal strains was isolated from 40% of the ants (N = 42). We found 16 fungal species in 13 genera associated with the ant workers. The prevalent fungal genera were Aspergillus, Purpureocillium and Fusarium. The ants Tapinoma melanocephalum, Paratrechina longicornis and Pheidole megacephala were associated with six fungal genera; and four genera of fungi were associated with Solenopsis saevissima workers. Fungal diversity was higher in the following hospital areas: nursery, hospital beds, breastmilk bank and paediatrics. CONCLUSION: Ants act as carriers of soil and airborne fungal species, and ant control in hospital areas is necessary to prevent the dissemination of such micro-organisms.


Asunto(s)
Hormigas/microbiología , Hongos/clasificación , Hongos/aislamiento & purificación , Insectos Vectores , Animales , Brasil , Hospitales Públicos
3.
Nutr Res ; 33(1): 76-84, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23351413

RESUMEN

Mushroom extracts are increasingly sold as dietary supplements because of several of their properties, including the enhancement of immune function and antitumor activity. We hypothesized that soluble polar substances present in mushroom extracts may show antioxidant and anticancer properties. This report shows that Brazilian aqueous extracts of Lentinula edodes and Pleurotus sajor-caju exert inhibitory activity against the proliferation of the human tumor cell lines laryngeal carcinoma (Hep-2) and cervical adenocarcinoma (HeLa). Cell viability was determined after using 3 different temperatures (4°C, 22°C, and 50°C) for mushroom extraction. Biochemical assays carried out in parallel indicated higher amounts of polyphenols in the L edodes extracts at all extraction temperatures investigated. The scavenging ability of the 2,2-diphenyl-1-picrylhydrazyl radical showed higher activity for L edodes extracts. Superoxide dismutase-like activity showed no statistically significant difference among the groups for the 2 tested extracts, and catalase-like activity was increased with the L edodes extracts at 4°C. The results for the cytotoxic activity from P sajor-caju extracts at 22°C revealed the half maximal inhibitory concentration values of 0.64% ± 0.02% for Hep-2 and 0.25% ± 0.02% for HeLa. A higher cytotoxic activity was found for the L edodes extract at 22°C, with half maximal inhibitory concentration values of 0.78% ± 0.02% for Hep-2 and 0.57% ± 0.01% for HeLa. Substantial morphological modifications in cells were confirmed by Giemsa staining after treatment with either extract, suggesting inhibition of proliferation and induction of apoptosis with increasing extract concentrations. These results indicate that the aqueous extracts of Brazilian L edodes and P sajor-caju mushrooms are potential sources of antioxidant and anticancer compounds. However, further investigations are needed to exploit their valuable therapeutic uses and to elucidate their modes of action.


Asunto(s)
Antineoplásicos/farmacología , Antioxidantes/farmacología , Pleurotus/química , Hongos Shiitake/química , Apoptosis/efectos de los fármacos , Compuestos de Bifenilo/farmacología , Brasil , Catalasa/análisis , Catalasa/metabolismo , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células HeLa , Células Hep G2 , Humanos , Picratos/farmacología , Polifenoles/farmacología , Superóxido Dismutasa/análisis , Superóxido Dismutasa/metabolismo
4.
Actas Urol Esp ; 36(10): 608-12, 2012.
Artículo en Español | MEDLINE | ID: mdl-22728019

RESUMEN

OBJECTIVES: To identify clinical application of intermittent hormonotherapy in prostatic carcinoma. MATERIAL AND METHODS: We conducted a systematic review in MEDLINE database and COCHRANE Library using the words MeSH "prostate cancer, androgenic deprivation and intermittent". There were included those with the best level of evidence and published in the last 10 years. RESULTS: Intermittent hormone therapy is one of the tools we use in urological armamentarium for special circumstances. This analysis highlights: possibility to regain sexual function during the period of suspension of treatment (time off) due to the recovery of testosterone levels also demonstrating an improvement in symptoms, decreased costs preserving the same oncological control compared to complete androgenic deprivation. CONCLUSIONS: There is still controversy about the benefits in quality of life and the emergence of long-term side effects typical of continuous hormonal therapy. Therefore and until now, we should only propose intermittent therapy in selected patients.


Asunto(s)
Antagonistas de Andrógenos/administración & dosificación , Antineoplásicos Hormonales/administración & dosificación , Neoplasias de la Próstata/tratamiento farmacológico , Esquema de Medicación , Humanos , Masculino
5.
J Chromatogr Sci ; 47(9): 844-6, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19835701

RESUMEN

Thin layer chromatography (TLC) stained with hot acidic p-anisaldehyde, is an interesting, fast, and low-cost technique to monitor main lipid contaminants such as triacylglycerols, diacylglycerols, and monoacylglycerols in biodiesel. These acylglycerols are detectable by the proposed planar chromatographic method, provided the content of the contaminants exceeds the limits recommended by the international norms applicable to biodiesel quality/specification, namely 0.25% in mass for total combined glycerin. The TLC data are confirmed by gas chromatography of the methyl esters of soy oil.


Asunto(s)
Biocombustibles/análisis , Cromatografía en Capa Delgada/métodos , Glicéridos/análisis , Cromatografía de Gases/métodos
6.
J Pept Res ; 64(3): 95-103, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15317499

RESUMEN

Eumenine mastoparan-AF (EMP-AF) is a novel membrane active tetradecapeptide recently isolated from the venom of solitary wasp, Anterhynchium flavomarginatum micado. It was reported previously that EMP-AF peptide presented low cytolytic activities in human erythrocytes and in RBL-2H3 mast cells. In the present work, we observed that this peptide is able to permeate anionic liposomes, and in less extension also the neutral ones. We present evidences showing that the permeation ability is well correlated with the amount of helical conformation assumed by the peptides in these environments. This peptide also showed a broad-spectrum inhibitory activity against Gram-positive and Gram-negative bacteria. The permeability of liposomes and the antibiotic effect showed a significant reduction when C-terminus was deamidated (in acidic form). The removal of the three first amino acid residues from the N-terminus rendered the peptide inactive both in liposomes and in bacteria. The results suggest that the mechanism of action involves a threshold in the accumulation of the peptide at level of cell membrane.


Asunto(s)
Antibacterianos/química , Antibacterianos/farmacología , Proteínas de Insectos/química , Proteínas de Insectos/farmacología , Venenos de Avispas/química , Venenos de Avispas/farmacología , Secuencia de Aminoácidos , Animales , Permeabilidad de la Membrana Celular/efectos de los fármacos , Dicroismo Circular , Humanos , Técnicas In Vitro , Proteínas de Insectos/genética , Liposomas , Pruebas de Sensibilidad Microbiana , Datos de Secuencia Molecular , Conformación Proteica , Venenos de Avispas/genética , Avispas/química , Avispas/genética
7.
J Oral Rehabil ; 30(9): 936-43, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12950976

RESUMEN

The effect of different anatomic shapes and materials of posts in the stress distribution on an endodontically treated incisor was evaluated in this work. This study compared three post shapes (tapered, cylindrical and two-stage cylindrical) made of three different materials (stainless steel, titanium and carbon fibre on Bisphenol A-Glycidyl Methacrylate (Bis-GMA) matrix). Two-dimensional stress analysis was performed using the Finite Element Method. A static load of 100N was applied at 45 degrees inclination with respect to the incisor's edge. The stress concentrations did not significantly affect the region adjacent to the alveolar bone crest at the palatine portion of the tooth, regardless of the post shape or material. However, stress concentrations on the post/dentin interface on the palatine side of the tooth root presented significant variations for different post shapes and materials. Post shapes had relatively small impact on the stress concentrations while post materials introduced higher variations on them. Stainless steel posts presented the highest level of stress concentration, followed by titanium and carbon/Bis-GMA posts.


Asunto(s)
Restauración Dental Permanente/normas , Análisis del Estrés Dental/métodos , Incisivo/fisiología , Bisfenol A Glicidil Metacrilato/análisis , Análisis de Elementos Finitos , Humanos , Técnica de Perno Muñón , Acero Inoxidable/análisis , Titanio/análisis
8.
Biochim Biophys Acta ; 1550(1): 70-80, 2001 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-11738089

RESUMEN

A novel antimicrobial peptide, anoplin, was purified from the venom of the solitary wasp Anoplius samariensis. The sequence was mostly analyzed by mass spectrometry, which was corroborated by solid-phase synthesis. Anoplin, composed of 10 amino acid residues, Gly-Leu-Leu-Lys-Arg-Ile-Lys-Thr-Leu-Leu-NH2, has a high homology to crabrolin and mastoparan-X, the mast cell degranulating peptides from social wasp venoms, and, therefore, can be predicted to adopt an amphipathic alpha-helix secondary structure. In fact, the circular dichroism (CD) spectra of anoplin in the presence of trifluoroethanol or sodium dodecyl sulfate showed a high content, up to 55%, of the alpha-helical conformation. A modeling study of anoplin based on its homology to mastoparan-X supported the CD results. Biological evaluation using the synthetic peptide revealed that this peptide exhibited potent activity in stimulating degranulation from rat peritoneal mast cells and broad-spectrum antimicrobial activity against both Gram-positive and Gram-negative bacteria. Therefore, this is the first antimicrobial component to be found in the solitary wasp venom and it may play a key role in preventing potential infection by microorganisms during prey consumption by their larvae. Moreover, this peptide is the smallest among the linear alpha-helical antimicrobial peptides hitherto found in nature, which is advantageous for chemical manipulation and medical application.


Asunto(s)
Antibacterianos/aislamiento & purificación , Oligopéptidos/química , Oligopéptidos/aislamiento & purificación , Venenos de Avispas/química , Venenos de Avispas/aislamiento & purificación , Secuencia de Aminoácidos , Animales , Antibacterianos/química , Antibacterianos/farmacología , Péptidos Catiónicos Antimicrobianos , Degranulación de la Célula , Cromatografía Líquida de Alta Presión , Dicroismo Circular , Femenino , Mastocitos/efectos de los fármacos , Mastocitos/fisiología , Pruebas de Sensibilidad Microbiana , Modelos Moleculares , Oligopéptidos/farmacología , Ratas , Alineación de Secuencia , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Venenos de Avispas/farmacología , Avispas
9.
Arq Neuropsiquiatr ; 59(3-B): 812-4, 2001 Sep.
Artículo en Portugués | MEDLINE | ID: mdl-11593290

RESUMEN

In the last few years we have been able to diagnose a larger number of cases of Moebius syndrome, perhaps due to its increased incidence--since a number of environmental factors have been related to the genesis of the syndrome. Out of the cases evaluated in two specialized ambulatory, it is worthwhile to mention one of them due to an uncommon association with cortical heterotopy, among others malformations.


Asunto(s)
Encefalopatías/diagnóstico , Síndrome de Mobius/diagnóstico , Encéfalo/anomalías , Encéfalo/patología , Encefalopatías/complicaciones , Preescolar , Humanos , Imagen por Resonancia Magnética , Masculino , Síndrome de Mobius/complicaciones
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