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1.
Morphologie ; 102(337): 78-82, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29625795

RESUMEN

Venous punctures are among the most common procedures performed by healthcare professionals. In particular, the cubital fossa is the site where the venous accesses are frequently made due to the number of superficial veins and the numerous anastomoses in this region. The arrangement of these venous connections is of particular interest for clinical application in several areas, thus, the healthcare professional must possess knowledge about these vessels and their anatomical relationships. The present study aims to analyze the venous pattern of the cubital fossa among individuals from Brazil. This study was approved by a Research Ethics Committee. The sample had 100 healthy individuals (50 men and 50 women). The superficial veins of the cubital fossa were analyzed with the aid of a sphygmomanometer. When inflated, the pressure in the forearm increased and the veins became prominent. It was observed that in the selected sample the types with the highest prevalence were the Type I and Type VII, both with 22% in 200 limbs studied. The chi2 test showed a significant statistical difference between the anastomosis pattern and the sex of the studied sample. The anastomotic pattern of the superficial veins of the studies sample is similar to African, European and Asian populations. The study of these variations is necessary to provide scientific basis for the healthcare professional during a venipuncture in order to avoid iatrogenic errors and damages in cutaneous nerves or neighboring arteries.


Asunto(s)
Variación Anatómica , Codo/irrigación sanguínea , Errores Médicos/prevención & control , Flebotomía/efectos adversos , Venas/anatomía & histología , Adolescente , Adulto , Arterias/anatomía & histología , Brasil , Codo/inervación , Femenino , Voluntarios Sanos , Humanos , Masculino , Persona de Mediana Edad , Flebotomía/métodos , Factores Sexuales , Piel/irrigación sanguínea , Piel/inervación , Esfigmomanometros , Adulto Joven
2.
Colloids Surf B Biointerfaces ; 164: 201-209, 2018 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-29413597

RESUMEN

In this work, we provide proof-of-concept of formation, physical characteristics and potential use as a drug delivery formulation of Pickering emulsions (PE) obtained by a novel method that combines nanoprecipitation with subsequent spontaneous emulsification process. To this end, pre-formed ultra-small (d.∼10 nm) nanoprecipitated nanoparticles of hydrophobic derivatives of cashew tree gum grafted with polylactide (CGPLAP), were conceived to stabilize Pickering emulsions obtained by spontaneous emulsification. These were also loaded with Amphotericin B (AmB), a drug of low oral bioavailability used in the therapy of neglected diseases such as leishmaniasis. The graft reaction was performed in two CG/PLA molar ratio conditions (1:1 and 1:10). Emulsions were prepared by adding the organic phase (Miglyol 812®) in the aqueous phase (nanoprecipitated CGPLAP), resulting the immediate emulsion formation. The isolation by centrifugation does not destabilize or separate the nanoparticles from oil droplets of the PE emulsion. Emulsions with CGPLAP 1:1 presented unimodal distributions at different CGPLA concentration, lower values in size and PDI and the best stability over time. The AmB was incorporated in the emulsions with a process efficiency of 21-47%, as determined by UV-vis. AmB in CGPLAP emulsions is in less aggregated state than observed in commercial AmB formulation.


Asunto(s)
Anfotericina B/farmacología , Anacardium/química , Composición de Medicamentos , Nanopartículas/química , Gomas de Plantas/síntesis química , Poliésteres/síntesis química , Anfotericina B/química , Precipitación Química , Emulsiones/química , Tamaño de la Partícula , Gomas de Plantas/química , Espectrofotometría Ultravioleta , Electricidad Estática
3.
Carbohydr Polym ; 101: 1013-7, 2014 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-24299869

RESUMEN

Dimorphandra gardneriana galactomannan (DG) was sulfated in pyridine:formamide using chlorosulfonic acid as the sulfation agent. The degree of substitution was 0.32, determined from the sulfur percentage. Confirmation of sulfation was obtained by FTIR spectroscopy through the presence of an asymmetrical SO stretching vibration at 1,259 cm(-1). NMR data showed that the sulfation occurred on primary hydroxyl groups. NMR and GPC data indicate degradation during reaction with elimination of galactose. At the maximum tested concentration of 1,000 µg/mL, unmodified DG polysaccharide did not show a statistically significant cytotoxicity in Vero cells by the MTT method. Therefore, the CC50>1,000 µg/mL obtained for the sulfated polysaccharides from D. gardneriana in Vero cells point to its lower cytotoxicity than the sulfated galactomannan from Mimosa scabrella.


Asunto(s)
Fabaceae/química , Mananos/química , Mananos/toxicidad , Sulfatos/química , Pruebas de Toxicidad , Animales , Chlorocebus aethiops , Galactosa/análogos & derivados , Mananos/aislamiento & purificación , Semillas/química , Células Vero
4.
Mater Sci Eng C Mater Biol Appl ; 32(6): 1588-93, 2012 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-24364964

RESUMEN

The search for bioactive molecules to be employed as recognition elements in biosensors has stimulated researchers to pore over the rich Brazilian biodiversity. In this sense, we introduce the use of natural cashew gum (Anacardium occidentale L.) as an active biomaterial to be used in the form of layer-by-layer films, in conjunction with phthalocyanines, which were tested as electrochemical sensors for dopamine detection. We investigated the effects of chemical composition of cashew gum from two different regions of Brazil (Piauí and Ceará states) on the physico-chemical characteristics of these nanostructures. The morphology of the nanostructures containing cashew gum was studied by atomic force microscopy which indicates that smooth films punctuated by globular features were formed that showed low roughness values. The results indicate that, independent of the origin, cashew gum stands out as an excellent film forming material with potential application in nanobiomedical devices as electrochemical sensors.


Asunto(s)
Anacardium/química , Materiales Biocompatibles/química , Nanoestructuras/química , Técnicas Biosensibles/métodos , Dopamina/química , Indoles/química , Isoindoles
5.
Vet Parasitol ; 173(1-2): 147-51, 2010 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-20643506

RESUMEN

Fasciola hepatica is a parasitic helminth that predominantly infects the liver and bile ducts of cattle and causes great losses of cattle production in the southern and southeastern regions of Brazil. The generation of liver lesions and the consequent inflammatory responses are intimately related to the migration of this parasite. The CC-group of chemokines plays a crucial role in the attraction of several cell types and in the recruitment of additional macrophages to an inflammatory focus in numerous diseases. In order to evaluate the role of CCL3 in the development of F. hepatica, we compared parasitological and pathological parameters in C57Bl/6J mice that were assigned to one of two experimental groups: the first group contained CCL3-producing mice (CCL3(+/+) mice) and the other group contained mice that were genetically deficient in CCL3 production (CCL3(-/-) mice). The mortality rate in the CCL3 non-deficient group was higher than of the deficient animals. In most animals from both experimental groups, the necropsied animals contained hemorrhages in their abdominal cavities. In the genetically modified animals, the lesioned liver areas were less extensive and presented focal and sub-capsular lesions. This work demonstrates that the development of F. hepatica is not affected by the absence of CCL3.


Asunto(s)
Quimiocina CCL3/genética , Fasciola hepatica , Fascioliasis/inmunología , Animales , Quimiocina CCL3/metabolismo , Heces/parasitología , Eliminación de Gen , Regulación de la Expresión Génica , Hígado/patología , Hepatopatías/parasitología , Hepatopatías/patología , Ratones , Ratones Endogámicos C57BL
6.
J. venom. anim. toxins incl. trop. dis ; 16(2): 311-323, 2010. graf, tab
Artículo en Inglés | LILACS | ID: lil-548852

RESUMEN

Snakebites comprise a serious health problem in several countries due to their global incidence, which exceeds 2.5 million per year, and the elevated number of victim fatalities. To counteract envenomations, antivenoms have been used regularly for more than a century. Apart from side effects including anaphylactic reactions, antivenoms are not able to efficiently neutralize local tissue damage, which contributes to increasing the severity and morbidity observed in patients. This fact, in turn, may be responsible for economic hardship, particularly in rural populations of developing countries. In the present work, we evaluated the antiophidian properties of 12 Brazilian plant extracts against the hemolytic, coagulant, hemorrhagic and proteolytic effects of Lachesis muta venom. Taken together, our data revealed that most of these aqueous products were capable of inhibiting those activities at different levels, except for Sapindus saponaria extract. In contrast, Stryphnodendron barbatiman extract completely neutralized all the analyzed biological activities. Thus, we may conclude that Brazilian flora may also be useful against L. muta accidents.


Asunto(s)
Animales , Ratas , Antivenenos , Lachesis muta , Extractos Vegetales , Fitoterapia
7.
Transplant Proc ; 40(3): 780-1, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18455015

RESUMEN

BACKGROUND: Split liver transplantation (SLT) increases organ supply for hepatic transplantation. Long-term patient survival and complication rates seem to be equivalent between orthotopic liver transplantation (OLT) and SLT. There are controversies among transplant physicians due to an ethical dilemma between benefiting individual needs or those of society. Barshes and Goss (Am J Transplant 5:2047, 2005) demonstrated that the majority of adult liver transplant candidates are favorable to SLT. The aim of our study was to evaluate the opinions of patients at a Brazilian university hospital regarding SLT. MATERIALS AND METHODS: A questionnaire with 14 questions was applied to 50 patients included in a hepatic transplant waiting list regarding SLT. RESULTS: The overall attitudes of 66% of the participants were classified as utilitarian, 31% were classified as self-preserving, and 3% were undecided. Ninety-one percent of patients would be willing to share even if their expected survival after SLT was shorter than that with OLT. For 77% of patients, children must have priority over adults. However, 83% were unaware of the donors for pediatric transplantations. CONCLUSIONS: SLT is a consistent solution for organ demand despite controversies among transplant physicians. The present study demonstrated that most patients were favorable to SLT. In conclusion, attitudes toward graft sharing are not barriers to SLT.


Asunto(s)
Actitud Frente a la Salud , Trasplante de Hígado/métodos , Trasplante de Hígado/estadística & datos numéricos , Listas de Espera , Adulto , Humanos , Trasplante de Hígado/psicología , Asignación de Recursos/métodos , Encuestas y Cuestionarios , Donantes de Tejidos/provisión & distribución , Obtención de Tejidos y Órganos/métodos
8.
Int Endod J ; 41(4): 296-302, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18217996

RESUMEN

AIM: To evaluate ex vivo degradation of gutta-percha following six thermoplastic obturation techniques. METHODOLOGY: Ninety human-extracted mandibular premolars were selected and divided randomly into nine groups for filling. Group 1: thermomechanical compaction for 3 s with Konne gutta-percha points (Konne Ind. e Com. de Mat. Odontol., Belo Horizonte, MG, Brazil); Group 2: thermomechanical compaction for 3 s with Dentsply TP gutta-percha points (Dentsply Indústria e Comércio Ltda, Petrópolis, R.J. Brazil); Group 3: thermomechanical compaction for 10 s with Konne; Group 4: thermomechanical compaction for 10 s with Dentsply TP; Group 5: warm vertical condensation using System B (EIE/Analytic, Richmond, WA, USA) with Konne; Group 6: warm vertical condensation using System B with Dentsply TP; Group 7: vertical condensation with Konne; Group 8: vertical condensation with Dentsply TP; Group 9: Microseal cone (Analytic Endodontics, Glendora, CA, USA). A further four groups were assessed without using teeth, Group 10: Microseal microflow (Analytic Endodontics); Group 11: Obtura (Obtura Corporation, Penton, MO, USA); Group 12: Obtura flow (Obtura Corporation); Group 13: Thermafil (Dentsply Maillefer, Tulsa, OK, USA). The filling material was removed from the root canal and trans-1,4-polyisoprene isolated by solubilization of the root filling remnants in chloroform followed by filtration and centrifugation. By gel permeation chromatography and infrared spectroscopy, the occurrence and degree of degradation were assessed. The results were analysed statistically using the Kruskal-Wallis test. With differential scanning calorimetry, the thermal behaviour of the gutta-percha was determined. RESULTS: A significant decrease in polymer molar mass and the production of carboxyl and hydroxyl groups in the polymer were observed with thermomechanical compaction used for 10 s and vertical condensation filling techniques (P = 0.0001 and P = 0.0005, respectively). Other techniques caused no polymer degradation. CONCLUSION: Polyisoprene degrades with high temperature. Thermomechanical compaction for 10 s and vertical condensation were associated with the greatest degradative process.


Asunto(s)
Gutapercha/química , Materiales de Obturación del Conducto Radicular/química , Diente Premolar , Rastreo Diferencial de Calorimetría , Cromatografía en Gel , Hemiterpenos/química , Calor , Humanos , Ensayo de Materiales , Peso Molecular , Obturación del Conducto Radicular , Espectroscopía Infrarroja por Transformada de Fourier , Estadísticas no Paramétricas
9.
Int Endod J ; 40(1): 25-30, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17209829

RESUMEN

AIM: To evaluate in vivo degradation of root filling materials over time. METHODOLOGY: Thirty-six root filled teeth with or without periapical lesions were selected. Teeth with poor coronal restoration were not included. The teeth had been root filled 3-30 years previous and were scheduled for conventional retreatment. The association of root canal treatment, age, periapical lesion and root filling degradation was investigated. The filling material was removed from the root canal using files and no solvent. Trans-1,4-polyisoprene was isolated through solubilization of root filling remnants in chloroform followed by filtration and centrifugation. Gel permeation chromatography (GPC) and infrared spectroscopy (FT-IR) were utilized to study the occurrence and degree of degradation. The GPC and FT-IR data were collected for each sample and analysed statistically using the Kruskal-Wallis test. RESULTS: Degradation of trans-1,4-polyisoprene was a slow process. The process was identified as an oxidation reaction through the production of carboxyl and hydroxyl groups. Compared with the control group, significant molar mass decrease was noted after 15 years (P = 0.0146) in teeth with no periapical lesions. However, in teeth associated with periapical lesions the number of years for significant degradation was reduced to 5 (P = 0.0009). CONCLUSION: Polyisoprene degrades inside root canals as an oxidative process. The presence of periapical lesions was associated with a more rapid onset of degradation.


Asunto(s)
Butadienos/química , Gutapercha/química , Hemiterpenos/química , Pentanos/química , Materiales de Obturación del Conducto Radicular/química , Biotransformación , Cromatografía en Gel , Fracaso de la Restauración Dental , Humanos , Oxidación-Reducción , Periodontitis Periapical/terapia , Retratamiento , Obturación del Conducto Radicular , Espectroscopía Infrarroja por Transformada de Fourier , Estadísticas no Paramétricas , Factores de Tiempo
10.
Int Endod J ; 36(4): 302-7, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12702126

RESUMEN

AIM: To determine the chemical composition of five commercially available nonstandardized gutta-percha points. METHODOLOGY: The organic fraction (gutta-percha polymer and wax/resin) of nonstandardized gutta-percha points (Dentsply, Tanari, Konne, Obtura Spartan and Analytic Endodontics) was separated from the inorganic fraction (ZnO and BaSO4) by dissolution in chloroform. Gutta-percha polymer was precipitated with acetone. Zinc oxide was partially separated from barium sulphate by reaction with HCl. Energy-dispersive X-ray microanalysis and X-ray diffraction were employed to identify the chemical elements and compounds (barium sulphate and zinc oxide). The barium sulphate content was calculated by percentage of sulphur from elemental microanalysis. All analyses were repeated three times. RESULTS: The means and standard deviations of the percentage by weight of gutta-percha in the points were: Dentsply (14.5 +/- 0.70%), Tanari (15.6 +/- 0.66%), Obtura (17.7 +/- 0.35%), Konne (18.9 +/- 0.32%) and Analytic (20.4 +/- 0.40%). The mean and SD of the zinc oxide content were: Dentsply (84.3 +/- 0.50%), Tanari (82.0 +/- 0.72%), Obtura (69.5 +/- 0.21%), Konne (78.0 +/- 0.05%) and Analytic (66.5 +/- 0.50%). CONCLUSIONS: The method was appropriate to quantify gutta-percha and resin/wax components of gutta-percha points, but not barium sulphate and zinc oxide. An alternative procedure to determine barium sulphate and zinc oxide contents has been proposed based on elemental microanalysis of sulphur. Some brands of gutta-percha did not contain barium sulphate.


Asunto(s)
Gutapercha/química , Microanálisis por Sonda Electrónica , Difracción de Rayos X
11.
Int J Biol Macromol ; 29(1): 35-44, 2001 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-11429187

RESUMEN

The composition, structure and rheological properties and metal ions interaction with Enterolobium contortisilliquum gum were investigated. This gum contains galactose, arabinose, rhamnose and glucuronic acid as main monosaccharide components. 13C nuclear magnetic resonance spectroscopy revealed that the anomeric composition is similar to the Enterolobium cyclocarpum exudate, however no 4-O-methylglucuronic acid was detected for E. contortisilliquum. The rheological experiment resulted in a very similar flow behaviour to that found for E. cyclocarpum gum. The empirical stiffness parameter, B was determined (B=0.090) and suggested that the polysaccharide possesses semi-flexible chains. Cation affinity of the gum aqueous solution was determined by intrinsic viscosity measurements and gelation. The melting temperature of gels pointed to a charge/ionic radius ratio dependence for metal ions. Thermodynamic parameters (enthalpy and entropy) at the melting temperature were also calculated.


Asunto(s)
Compuestos de Aluminio/química , Cloruro de Calcio/química , Cloruros/química , Polisacáridos/química , Cloruro de Sodio/química , Cloruro de Aluminio , Fabaceae/química , Resonancia Magnética Nuclear Biomolecular , Plantas Medicinales , Sales (Química)
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