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1.
Acta odontol. Colomb. (En linea) ; 9(1): 24-36, 2019. Graf, Tab
Artigo em Espanhol | LILACS, COLNAL | ID: biblio-1000031

RESUMO

Introducción: el dolor es uno de los síntomas principales de los trastornos musculoesqueléticos y tiene alta frecuencia en los profesionales de la odontología. El objetivo del estudio fue determinar la prevalencia del dolor musculoesquelético y los factores sociodemográficos y laborales asociados en odontólogos que laboran en la ciudad de Cuenca, Ecuador. Materiales y métodos: se realizó un estudio transversal en 240 odontólogos inscritos en la Dirección Provincial de Salud del Azuay de la ciudad de Cuenca hasta el año 2015. Se usó el cuestionario de Kuorinka para determinar síntomas musculoesqueléticos. Se creó un formulario con variables sociodemográficas y las características del dolor para establecer asociaciones estadísticas. La información fue procesada en el programa SPSS versión 22. Resultados: el 58,7% eran mujeres. El promedio de edad fue de 37 años con una DE de 11,6. La prevalencia de dolor musculoesquelético fue del 73,3%. El 90,3% atribuyó el dolor a causas laborales. Los factores asociados al dolor fueron: sexo femenino, sedentarismo, trabajar en el sector público y carga horaria mayor a 30 horas semanales. El dolor musculoesquelético en los odontólogos está asociado estadísticamente a: sexo femenino (OR= 2,60; IC 95%= 1,35 ­ 4,99; p= 0,004), sedentarismo (OR= 2,42; IC 95%= 1,20 ­ 4,89; p= 0,013), ejercer en el área pública (OR= 2,97; IC 95%= 1,26 ­ 6,99; p= 0,012) y carga horaria mayor a 30 horas sema- nales (OR= 2,21; IC 95%= 1,15 ­ 4,21; p= 0,017). Conclusiones: el ejercicio de la práctica clínica odontológica constituye un factor de riesgo para la generación de trastornos musculoesqueléticos.


Assuntos
Humanos , Saúde do Trabalhador , Dor Musculoesquelética , Prática Profissional , Jornada de Trabalho , Esgotamento Profissional , Prevalência , Odontólogos , Odontólogas , Equador
2.
J Colloid Interface Sci ; 538: 174-186, 2018 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-30504057

RESUMO

Biocompatible nanosystems exhibiting long-lifetime (∼millisecond) luminescence features are particularly relevant in the field of bioimaging. In this study, citrate-functionalized calcium-doped europium phosphates nanophosphors of the rhabdophane type were prepared at different synthesis times by a bioinspired crystallization route, consisting in thermal decomplexing of Ca2+/Eu3+ /citrate/phosphate/carbonate solutions. The general formula of this material is CaαEu1-α(PO4)1-α(HPO4)α·nH2O, with α ranging from 0 to 0.58 and n ∼ 1. A thorough characterization of the nanoparticles has been carried out by XRD (including data processing with Topas 6.0), HR-TEM, TEM, FTIR, TG/DTA, ICP, dynamic light scattering (DLS), electrophoretic mobility, and fluorescence spectroscopy. Based on these results a crystallization mechanism involving the filling of cationic sites with Ca2+ions associated to a concomitant adjustment of the PO4/HPO4 ratio was proposed. Upon calcium doping, the aspect ratio of the nanoparticles as well as of the crystalline domains decreased and the relative luminescence intensity (R.L.I.) could be modulated. Neither the pH nor the ionic strength, nor the temperature (from 25 to 37 °C) affected significantly the R.L.I. of particles after resuspension in water, leading to rather steady luminescence features usable in a large domain of conditions. This new class of luminescent compounds has been proved to be fully cytocompatible relative to GTL-16 human carcinoma cells and showed an improved cytocompatibility as the Ca2+ content increased when contacted with the more sensitive m17. ASC murine mesenchymal stem cells. These biocompatible nanoparticles thus appear as promising new tailorable tools for biomedical applications as luminescent nanoprobes.

3.
Langmuir ; 34(45): 13713-13724, 2018 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-30394747

RESUMO

New biomimetic magnetite nanoparticles (hereafter BMNPs) with sizes larger than most common superparamagnetic nanoparticles were produced in the presence of the recombinant MamC protein from Magnetococcus marinus MC-1 and functionalized with doxorubicin (DOXO) intended as potential drug nanocarriers. Unlike inorganic magnetite nanoparticles, in BMNPs the MamC protein controls their size and morphology, providing them with magnetic properties consistent with a large magnetic moment per particle; moreover, it provides the nanoparticles with novel surface properties. BMNPs display the isoelectric point at pH 4.4, being strongly negatively charged at physiological pH (pH 7.4). This allows both (i) their functionalization with DOXO, which is positively charged at pH 7.4, and (ii) the stability of the DOXO-surface bond and DOXO release to be pH dependent and governed by electrostatic interactions. DOXO adsorption follows a Langmuir-Freundlich model, and the coupling of DOXO to BMNPs (binary biomimetic nanoparticles) is very stable at physiological pH (maximum release of 5% of the drug adsorbed). Conversely, when pH decreases, these electrostatic interactions weaken, and at pH 5, DOXO is released up to ∼35% of the amount initially adsorbed. The DOXO-BMNPs display cytotoxicity on the GTL-16 human gastric carcinoma cell line in a dose-dependent manner, reaching about ∼70% of mortality at the maximum amount tested, while the nonloaded BMNPs are fully cytocompatible. The present data suggest that BMNPs could be useful as potential drug nanocarriers with a drug adsorption-release governed by changes in local pH values.

4.
Sci Rep ; 8(1): 17016, 2018 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-30451901

RESUMO

Demineralization of dental hard tissue is a widespread problem and the main responsible for dental caries and dentin hypersensitivity. The most promising strategies to induce the precipitation of new mineral phase are the application of materials releasing gradually Ca2+ and PO43- ions or mimicking the mineral phase of the host tissue. However, the design of formulations covering both processes is so far a challenge in preventive dentistry. In this work, we have synthesized innovative biomimetic amorphous calcium phosphate (ACP), which has been, for the first time, doped with fluoride ions (FACP) to obtain materials with enhanced anti-caries and remineralizing properties. Significantly, the doping with fluoride (F) did not vary the physico-chemical features of ACP but resulted in a faster conversion to the crystalline apatite phase in water, as observed by in-situ time-dependent Raman experiments. The efficacy of the as synthesized ACP and FACP samples to occlude dentinal tubules and induce enamel remineralization has been tested in vitro in human molar teeth. The samples showed good ability to partially occlude the tubules of acid-etched dentin and to restore demineralized enamel into its native structure. Results demonstrate that ACP and FACP are promising biomimetic materials in preventive dentistry to hinder demineralization of dental hard tissues.

5.
Neurocirugía (Soc. Luso-Esp. Neurocir.) ; 29(5): 217-224, sept.-oct. 2018. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-180313

RESUMO

Objetivo: Este estudio busca describir casos de trauma craneoencefálico debido a heridas por proyectil de arma de fuego, en población civil mayor de 18 años, atendidos en un hospital de referencia y realizar una comparación de los pacientes de acuerdo a los resultados clínicos al egreso. Métodos: Se trata de un estudio descriptivo, observacional, retrospectivo a través de la revisión de historias clínicas de los pacientes mayores de 18 años que ingresaron en la sala de urgencias de la Fundación Valle del Lili en Cali, Colombia con trauma craneoencefálico secundario a heridas por proyectil de arma de fuego, en contexto civil, entre enero del 2010 y febrero del 2016. Se realizó un análisis univariado para determinar factores asociados a muerte y resultados clínicos adversos. Resultados: Se incluyó un total de 95 pacientes con trauma craneoencefálico por heridas por proyectil de arma de fuego en el contexto civil. El 91,6% fue de sexo masculino, el principal contexto fue violencia interpersonal en un 54,7%, el método de transporte más común fue ambulancia terrestre en un 79%, el puntaje de Glasgow (GCS) al ingreso fue 3-8 = 64,2%; 9-12 = 6,3%; 13-15=28,4%. Al ingreso se le tomó TAC simple a 82 (86,3%) pacientes dentro de la primera hora, encontrando una clasificación de Marshall entre I-III en 60,9%, un valor de IV en el 17,8% y entre V-VI en un 4,1%. La trayectoria era penetrante no transfixiante en el 43,2%, transfixiante en el 27,4% y tangencial en el 9,5%. La mortalidad fue del 45,3%, de esta 39% ocurrió en las primeras 24h. Conclusiones: Un mayor compromiso en el estado general del paciente al ingreso determina un pobre pronóstico y mayor probabilidad de muerte en las primeras 24 h


Objective: This study aims to describe cases of traumatic brain injury due to gunshot wounds in civilian population over 18 years of age, treated at a referral hospital in Cali, Colombia and compare the clinical outcomes at discharge. Methods: An observational, descriptive cross-sectional study was conducted by retrospectively collecting clinical data related to adult patients that presented traumatic brain injury due to civil gunshot-wounds and that consulted to the emergency room at Fundación Valle del Lili Hospital in Cali, Colombia between January 2010 and February of 2016. A univariate analysis was performed to determine factors associated with death and adverse clinical outcomes. Results: A total of 95 patients older than 18 years, with traumatic brain injury by gunshot were included in the civil context. The 91.6% were male. The main context was interpersonal violence with 54.7%. The most common method of transportation was by ambulance (79%). The Glasgow score at admission was 3-8 in 64.2% of cases; 9-12 in 6.32% and 13-15 in 28.4%. On admission, head CT scan was performed in 82 (86.3%) patients within the first hour, finding a Marshall-Score between I-III in 60.9%, of IV in 17.8% of cases and a score between V-VI and in 4.1%. The trajectory was non-transfixing penetrating in 43.2%, transfixing in 27.3% and tangential in 9.5%. Mortality was 45.3% in total, 39% died within the first 24hours. Conclusions: A major compromise on admission determines an overall poorer prognosis and a high likelihood of death in the first 24-hours


Assuntos
Humanos , Masculino , Feminino , Adulto , Lesões Encefálicas Traumáticas/diagnóstico , Lesões Encefálicas Traumáticas/mortalidade , Ferimentos por Arma de Fogo/complicações , Prognóstico , Estudos Retrospectivos , Análise Estatística , Lesões Encefálicas Traumáticas/complicações
6.
Neurocirugia (Astur) ; 29(5): 217-224, 2018 Sep - Oct.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-29934069

RESUMO

OBJECTIVE: This study aims to describe cases of traumatic brain injury due to gunshot wounds in civilian population over 18 years of age, treated at a referral hospital in Cali, Colombia and compare the clinical outcomes at discharge. METHODS: An observational, descriptive cross-sectional study was conducted by retrospectively collecting clinical data related to adult patients that presented traumatic brain injury due to civil gunshot-wounds and that consulted to the emergency room at Fundación Valle del Lili Hospital in Cali, Colombia between January 2010 and February of 2016. A univariate analysis was performed to determine factors associated with death and adverse clinical outcomes. RESULTS: A total of 95 patients older than 18 years, with traumatic brain injury by gunshot were included in the civil context. The 91.6% were male. The main context was interpersonal violence with 54.7%. The most common method of transportation was by ambulance (79%). The Glasgow score at admission was 3-8 in 64.2% of cases; 9-12 in 6.32% and 13-15 in 28.4%. On admission, head CT scan was performed in 82 (86.3%) patients within the first hour, finding a Marshall-Score between I-III in 60.9%, of IV in 17.8% of cases and a score between V-VI and in 4.1%. The trajectory was non-transfixing penetrating in 43.2%, transfixing in 27.3% and tangential in 9.5%. Mortality was 45.3% in total, 39% died within the first 24hours. CONCLUSIONS: A major compromise on admission determines an overall poorer prognosis and a high likelihood of death in the first 24-hours.

7.
Sci Rep ; 7(1): 8901, 2017 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-28827557

RESUMO

The surface structure and hydrophilicity of synthetic nanocrystalline apatite with strongly bound citrates on their surface are here investigated at the molecular level, by combining advanced IR spectroscopy, microgravimetry and adsorption microcalorimetry. Citrate are found to form unidentate-like and ionic-like complexes with surface Ca2+ ions, with a surface coverage closely resembling that present in bone apatite platelets (i.e., 1 molecule/(n nm)2, with n ranging between 1.4 and 1.6). These surface complexes are part of a hydrated non-apatitic surface layer with a sub-nanometre thickness. Noticeably, it is found that the hydrophilicity of the nanoparticles, measured in terms of adsorption of water molecules in the form of multilayers, decreases in a significant extent in relation to the presence of citrates, most likely because of the exposure toward the exterior of -CH2 groups. Our findings provide new insights on the surface properties of bio-inspired nano-apatites, which can be of great relevance for better understanding the role of citrate in determining important interfacial properties, such as hydrophobicity, of bone apatite platelets. The evaluation and comprehension of surface composition and structure is also of paramount interest to strictly control the functions of synthetic biomaterials, since their surface chemistry strongly affects the hosting tissue response.

8.
Blood Adv ; 1(13): 824-834, 2017 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-29296726

RESUMO

Hemophilia A and B are rare, X-linked bleeding disorders. My Life, Our Future (MLOF) is a collaborative project established to genotype and study hemophilia. Patients were enrolled at US hemophilia treatment centers (HTCs). Genotyping was performed centrally using next-generation sequencing (NGS) with an approach that detected common F8 gene inversions simultaneously with F8 and F9 gene sequencing followed by confirmation using standard genotyping methods. Sixty-nine HTCs enrolled the first 3000 patients in under 3 years. Clinically reportable DNA variants were detected in 98.1% (2357/2401) of hemophilia A and 99.3% (595/599) of hemophilia B patients. Of the 924 unique variants found, 285 were novel. Predicted gene-disrupting variants were common in severe disease; missense variants predominated in mild-moderate disease. Novel DNA variants accounted for ∼30% of variants found and were detected continuously throughout the project, indicating that additional variation likely remains undiscovered. The NGS approach detected >1 reportable variants in 36 patients (10 females), a finding with potential clinical implications. NGS also detected incidental variants unlikely to cause disease, including 11 variants previously reported in hemophilia. Although these genes are thought to be conserved, our findings support caution in interpretation of new variants. In summary, MLOF has contributed significantly toward variant annotation in the F8 and F9 genes. In the near future, investigators will be able to access MLOF data and repository samples for research to advance our understanding of hemophilia.

9.
Cryst Growth Des ; 16(8): 4173-4177, 2016 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-27512345

RESUMO

The molecular structure of the units that get incorporated into the nuclei of the crystalline phase and sustain their growth is a fundamental issue in the pathway from a supersaturated solution to the formation of crystals. Using a fluorescent dye we have recorded the variation of the pH value in time along a gel where CaCl2 and NaHCO3 counter-diffuse to crystallize CaCO3. The same pH-space-time distribution maps were also computationally obtained using a chemical speciation code (phreeqc). Using data arising from this model we investigated the space-time evolution of the activity of the single species (ions and ion pairs) involved in the crystallization process. Our combined results suggest that, whatever the pathway from solution to crystals, the neutral pair CaCO3° is a key species in the CaCO3 precipitation system.

10.
Lancet ; 388(10039): 45-54, 2016 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-27103127

RESUMO

BACKGROUND: The thrombopoietin receptor agonist romiplostim could be an effective treatment in symptomatic children with persistent or chronic immune thrombocytopenia. We aimed to assess whether romiplostim is safe and effective in children with immune thrombocytopenia of more than 6 months' duration. METHODS: In this phase 3 double-blind study, eligible participants were children with immune thrombocytopenia aged 1 year to 17 years and mean platelet counts 30 × 10(9)/L or less (mean of two measurements during the screening period) with no single count greater than 35 × 10(9)/L, and were recruited from 27 sites in the USA, Canada, and Australia. Participants were randomly assigned (2:1) through the interactive voice response system to receive weekly romiplostim or placebo for 24 weeks stratified by age (1 year to <6 years, 6 years to <12 years, 12 years to <18 years), adjusting the dose weekly from 1 µg/kg to 10 µg/kg to target platelet counts of 50-200 × 10(9)/L. Patients and investigators were blinded to the treatment assignment. The primary analysis included all randomised patients and the safety analysis included all randomised patients who received at least one dose of investigational product. The primary endpoint, durable platelet response, was defined as achievement of weekly platelet responses (platelet counts ≥50 × 10(9)/L without rescue drug use in the preceding 4 weeks) in 6 or more of the final 8 weeks (weeks 18-25). This study is registered with ClinicalTrials.gov, NCT 01444417. FINDINGS: Between Jan 24, 2012, and Sept 3, 2014, 62 patients were randomly assigned; 42 to romiplostim and 20 to placebo. Durable platelet response was seen in 22 (52%) patients in the romiplostim group and two (10%) in the placebo group (p=0·002, odds ratio 9·1 [95% CI 1·9-43·2]). Durable platelet response rates with romiplostim by age were 38% (3/8) for 1 year to younger than 6 years, 56% (10/18) for 6 years to younger than 12 years, and 56% (9/16) for 12 years to younger than 18 years. One (5%) of 19 patients in the placebo group had serious adverse events compared with 10 (24%) of 42 patients in the romiplostim group. Of these serious adverse events, headache and thrombocytosis, in one (2%) of 42 patients in the romiplostim group, were considered treatment related. No patients withdrew due to adverse events. INTERPRETATION: In children with chronic immune thrombocytopenia, romiplostim induced a high rate of platelet response with no new safety signals. Ongoing romiplostim studies will provide further information as to long-term efficacy, safety, and remission in children with immune thrombocytopenia. FUNDING: Amgen Inc.


Assuntos
Púrpura Trombocitopênica Idiopática/tratamento farmacológico , Receptores Fc/uso terapêutico , Receptores de Trombopoetina/agonistas , Proteínas Recombinantes de Fusão/uso terapêutico , Trombopoetina/uso terapêutico , Adolescente , Criança , Pré-Escolar , Método Duplo-Cego , Feminino , Humanos , Lactente , Masculino , Contagem de Plaquetas , Púrpura Trombocitopênica Idiopática/sangue , Resultado do Tratamento
11.
Ginecol Obstet Mex ; 83(9): 522-8, 2015 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-26591040

RESUMO

BACKGROUND: Breast cancer is the leading cause of death from cancer in the female population; consequently, there are multiple prevention campaigns. Within these campaigns, a special emphasis is given on promoting monthly breast self-examination; however, many women have never received formal education on proper method of self-examination. OBJECTIVE: To establish if the educational intervention we propose improves the breast self-examination technique. MATERIAL AND METHODS: A descriptive longitudinal study that included 52 women aged 20-40 years, attending a Family Medicine Unit of the Mexican Institute of Social Security, who were evaluated about self-examination technique before and after educational intervention, measured on a scale of 0 to 16. Statistical analysis was made with descriptive statistics and Student's t test. RESULTS: The mean age was 30.76 ± 5.87 years. The mean baseline score was 3.13 ± 2.55. The final average score after a month of the educational intervention was 10.69 ± 2.74, which represents an increase in average score of 7.55 ± 3.53. There was a significant increase in assessment scores after the educational intervention (p < 0.001). CONCLUSIONS: "Supervised breast self-examination" technique showed an increase in the ability of self-examination in patients. It can be considered an effective complementary method of teaching breast self-examination.


Assuntos
Autoexame de Mama , Adulto , Neoplasias da Mama/prevenção & controle , Autoexame de Mama/normas , Feminino , Educação em Saúde/métodos , Humanos , Estudos Longitudinais , Adulto Jovem
12.
J Patient Saf ; 2015 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-26067748

RESUMO

OBJECTIVES: To evaluate the impact of the International Nosocomial Infection Control Consortium (INICC) multidimensional hand hygiene (HH) approach in Mexico, and analyze predictors of poor HH compliance. METHODS: From June 2002 to April 2006, we conducted a prospective, observational, before-and-after study in 8 intensive care units (ICUs) from 6 hospitals in 3 cities of Mexico. The approach included administrative support, availability of supplies, education and training, reminders in the workplace, process surveillance, and performance feedback. RESULTS: A total of 13,201 observations for HH opportunities were done in each ICU, during randomly selected 30-minute periods. Overall, HH compliance increased from 45% to 79% (95% confidence interval [CI], 69.1-86.5; P = 0.01). Univariate and multivariate analyses showed that several variables were significantly associated with poor HH compliance: males versus females (61% versus 66%; 95% CI, 0.91-0.96; P = 0.0001), physicians versus nurses (62% versus 67%; 95% CI, 0.91-0.97; P = 0.0001), and adult versus neonatal ICUs (67% versus 54%; 95% CI, 0.79-0.84; P = 0.0001), among others. CONCLUSIONS: Hand hygiene programs should focus on variables found to be predictors of poor HH compliance.

13.
Langmuir ; 31(5): 1766-75, 2015 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-25602940

RESUMO

Multifunctional biomimetic nanoparticles (NPs) are acquiring increasing interest as carriers in medicine and basic research since they can efficiently combine labels for subsequent tracking, moieties for specific cell targeting, and bioactive molecules, e.g., drugs. In particular, because of their easy synthesis, low cost, good biocompatibility, high resorbability, easy surface functionalization, and pH-dependent solubility, nanocrystalline apatites are promising candidates as nanocarriers. This work describes the synthesis and characterization of bioinspired apatite nanoparticles to be used as fluorescent nanocarriers targeted against the Met/hepatocyte growth factor receptor, which is considered a tumor associated cell surface marker of many cancers. To this aim the nanoparticles have been labeled with Fluorescein-5-isothiocyanate (FITC) by simple isothermal adsorption, in the absence of organic, possibly toxic, molecules, and then functionalized with a monoclonal antibody (mAb) directed against such a receptor. Direct labeling of the nanoparticles allowed tracking the moieties with spatiotemporal resolution and thus following their interaction with cells, expressing or not the targeted receptor, as well as their fate in vitro. Cytofluorometry and confocal microscopy experiments showed that the functionalized nanocarriers, which emitted a strong fluorescent signal, were rapidly and specifically internalized in cells expressing the receptor. Indeed, we found that, once inside the cells expressing the receptor, mAb-functionalized FITC nanoparticles partially dissociated in their two components, with some mAbs being recycled to the cell surface and the FITC-labeled nanoparticles remaining in the cytosol. This work thus shows that FITC-labeled nanoapatites are very promising probes for targeted cell imaging applications.


Assuntos
Anticorpos Monoclonais/química , Apatitas/química , Materiais Biomiméticos/química , Fluoresceína-5-Isotiocianato/química , Corantes Fluorescentes/química , Imagem Molecular/métodos , Nanopartículas/química , Anticorpos Monoclonais/imunologia , Transporte Biológico , Materiais Biomiméticos/síntese química , Materiais Biomiméticos/metabolismo , Linhagem Celular Tumoral , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/metabolismo , Humanos , Espaço Intracelular/metabolismo , Teste de Materiais , Proteínas Proto-Oncogênicas c-met/imunologia
14.
J Neurosci Nurs ; 47(1): E22-30, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25225835

RESUMO

BACKGROUND: The perceived pain on injection site caused by subcutaneous (SC) self-injection may negatively affect acceptance and adherence to treatment in patients with multiple sclerosis (MS). Pain on injection may be caused by inaccurate injection technique, inadequate needle length adjustment, or repeated use of the same injection body area. However, information is lacking concerning the optimal needle depth to minimize the injection pain. OBJECTIVE: The purpose of this program was to characterize the perceived injection-site pain associated with the use of various injection depths of the autoinjector of glatiramer acetate (GA) based on SC tissue thickness (SCT) of the injection site. METHODS: This was a pilot program performed by MS-specialized nurses in patients with MS new to GA. Patients were trained by MS nurses on the preparation and administration of SC injection and on an eight-site rotation (left and right arms, thighs, abdomen, and upper quadrant of the buttock). The needle length setting was selected based on SCT measures as follows: 4 or 6 mm for SCT < 25 mm, 6 or 8 mm for SCT between 25 and 50 mm, and 8 or 10 mm for SCT > 50 mm. Injection pain was rated using a visual analog scale (VAS) at 5- and 40-minute postinjection and during two 24-day treatment periods. RESULTS: Thirty-eight patients with MS were evaluated. The mean SCT ranged from 15.5 mm in the upper outer quadrant of the buttocks to 29.2 mm in the thighs. The mean perceived pain on injection was below 3 for all the injection sites, at both time points (5 and 40 minutes) and during both 24-day evaluation periods. The mean VAS scores were significantly greater after 5 minutes of injection compared with that reported 40-minute postinjection during both 24-day treatment periods and for all the injection areas. Mean VAS measures at 5- and 40-minute postinjection significantly decreased during the second 24-day treatment period with respect to that reported during the first 24 SC injections for all injection sites. CONCLUSIONS: Our findings suggest that the adjustment of injection depth of SC GA autoinjector according to SCT of body injection areas is suitable to maintain a low degree of postinjection pain. Moreover, our results also may indicate that the use of needle lengths of 6 mm or shorter is appropriate with regard to injection pain for adult patients with MS with SCT < 50 mm.


Assuntos
Acetato de Glatiramer/administração & dosagem , Injeções Subcutâneas/instrumentação , Injeções Subcutâneas/enfermagem , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Esclerose Múltipla Recidivante-Remitente/enfermagem , Agulhas , Medição da Dor/enfermagem , Pregas Cutâneas , Adulto , Criança , Feminino , Humanos , Lactente , Masculino , Adesão à Medicação , Pessoa de Meia-Idade , Avaliação em Enfermagem , Projetos Piloto , Autoadministração/instrumentação , Autoadministração/enfermagem
15.
J Mater Sci Mater Med ; 25(10): 2305-12, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24652593

RESUMO

A novel methodology for the assembly of collagen fibrils in microliter drops is proposed. It consists in the gradual increase of pH by means of vapour diffusion coming from the decomposition of NH4HCO3 solutions. The pH increase rate as well as the final steady pH of solutions containing collagen can be adjusted by varying the concentration of NH4HCO3. Both parameters are of predominant importance in collagen fibrillogenesis. The effect of these parameters on the kinetic of the fibrillogenesis process and on the fibrils morphology was studied. We found that both the kinetic and the morphology are mainly driven by electrostatic interactions. A gradual increase of pH slows down the formation of collagen fibres and favours the lateral interaction between fibrils producing broader fibres. On the other hand, a rapid increase of pH reduces the lateral electrostatic interactions favouring the formation of thinner fibres. The formation of the D-band periodicity is also a pH-dependent process that occurs after fibrillogenesis when the most stable state of fibres formation has been reached.


Assuntos
Colágeno Tipo I/metabolismo , Colágenos Fibrilares , Multimerização Proteica , Bicarbonatos/química , Colágeno Tipo I/química , Difusão , Colágenos Fibrilares/química , Colágenos Fibrilares/metabolismo , Concentração de Íons de Hidrogênio , Cinética , Nanofibras/química , Soluções , Volatilização
17.
Anal Chem ; 85(20): 9678-85, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-24040900

RESUMO

The use of SU-8-based optofluidic systems (OFS) is validated as an affordable and easy alternative to expensive glass device manufacturing for small-molecule crystallization studies and, in comparison with other polymers, able to withstand most organic solvents. A comparison between two identical OFS (using SU-8 and poly(dimethylsiloxane), PDMS) against the 36 most commonly used organic solvents for small-molecule crystallization studies have confirmed both the structural and optical stability of the SU-8, whereas PDMS suffered from unsealing or tearing in most cases. In order to test its compatibility, measurements before and after 24 h of continued exposure against solvents have been pursued. Here, three aspects have been considered: in the macroscale, swelling has been determined by analyzing the variations in the optical path in the OFS. For determining compatibility at microscale, fabricated SU-8 micropatterns were solvent-etched and subsequently characterized by scanning electron microscopy (SEM). Roughness of the polymer has also been studied through atomic force microscopy (AFM) measurements at the nanoscale. Experimental measurements of PDMS swelling were in accordance with previously reported observations, while SU-8 displayed a great stability against all the tested solvents. Through this experimental procedure we also show that the OFS are suitable for real-time, on-chip, UV-vis spectroscopy. Micro- and nanoscale observations did not show apparent corrosion on SU-8 surface. Also, two commonly used carrier fluids for microdroplet generation (FC-70 Fluorinert oil and silicone oil) were also tested against the different solvents with the aim of providing useful information for later microbatch experiments.

18.
Langmuir ; 29(41): 12628-32, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-24070240

RESUMO

We monitor the dissolution of arrayed picoliter-size sessile microdroplets of the aqueous phase in oil, generated using a recently developed fluidic device. Initial pinning of the microdroplet perimeter leads to a nearly constant contact diameter, thus contraction proceeds via microdroplet (micrometer-diameter) height and contact angle reductions. This confirms that picoliter microdroplets contraction or dissolution due to the selective diffusion of water in oil has comparable dynamics with microliter droplet evaporation in air. We observe a constant microdroplet dissolution rate in different aqueous solutions. The application of this simple model to solvent-diffusion-driven crystallization experiments in confined volumes, for instance, would allow us to determine precisely the concentration in the microdroplet during an experiment and particularly at nucleation.


Assuntos
Óleos/química , Termodinâmica , Cloreto de Cálcio/química , Carbonatos/química , Difusão , Tamanho da Partícula , Cloreto de Sódio/química , Soluções , Propriedades de Superfície , Água/química
19.
Langmuir ; 29(26): 8213-21, 2013 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-23735159

RESUMO

In this work, the efficiency of bioinspired citrate-functionalized nanocrystalline apatites as nanocarriers for delivery of doxorubicin (DOXO) has been assessed. The nanoparticles were synthesized by thermal decomplexing of metastable calcium/citrate/phosphate solutions both in the absence (Ap) and in the presence (cAp) of carbonate ions. The presence of citrate and carbonate ions in the solution allowed us to tailor the size, shape, carbonate content, and surface chemistry of the nanoparticles. The drug-loading efficiency of the two types of apatite was evaluated by means of the adsorption isotherms, which were found to fit a Langmuir-Freundlich behavior. A model describing the interaction between apatite surface and DOXO is proposed from adsorption isotherms and ζ-potential measurements. DOXO is adsorbed as a dimer by means of a positively charged amino group that electrostatically interacts with negatively charged surface groups of nanoparticles. The drug-release profiles were explored at pHs 7.4 and 5.0, mimicking the physiological pH in the blood circulation and the more acidic pH in the endosome-lysosome intracellular compartment, respectively. After 7 days at pH 7.4, cAp-DOXO released around 42% less drug than Ap-DOXO. However, at acidic pH, both nanoassemblies released similar amounts of DOXO. In vitro assays analyzed by confocal microscopy showed that both drug-loaded apatites were internalized within GTL-16 human carcinoma cells and could release DOXO, which accumulated in the nucleus in short times and exerted cytotoxic activity with the same efficiency. cAp are thus expected to be a more promising nanocarrier for experiments in vivo, in situations where intravenous injection of nanoparticles are required to reach the targeted tumor, after circulating in the bloodstream.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Apatitas/química , Citrato de Cálcio/química , Carbonatos/química , Doxorrubicina/administração & dosagem , Portadores de Fármacos , Nanopartículas/química , Antibióticos Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/farmacologia , Composição de Medicamentos , Humanos , Concentração de Íons de Hidrogênio , Cinética , Microscopia Eletrônica de Transmissão , Nanopartículas/ultraestrutura , Eletricidade Estática , Termodinâmica
20.
Rev. cuba. farm ; 47(2): 145-146, abr.-jun. 2013.
Artigo em Espanhol | LILACS | ID: lil-683072

RESUMO

Existe elevado consenso en que el conocimiento y la utilización de las características farmacológicas de un antimicrobiano, permite optimizar el efecto terapéutico en términos de eficacia y seguridad. Para ello, es fundamental considerar que entre paciente y fármaco, se establece una relación farmacocinética (relación P-F) particularmente individualizada y determinada por los valores de volumen de distribución, constante de eliminación y aclaramiento que alcanza el fármaco en el paciente, en las condiciones fisiopatológicas de este en un instante determinado. Si esta relación es farmacológicamente manejada de modo adecuado, debe proporcionar el mejor escenario para que el fármaco pueda producir sus máximos efectos terapéuticos.1,2El laboratorio clínico y sus técnicas actuales determinan con gran certeza la sensibilidad de un microorganismo a un antimicrobiano y la actividad bacteriostática o bactericida que este alcanza. Estas son características fundamentales en la eficacia de la terapia, pero no menos importantes son los procesos que tienen influencia y en definitiva, determinan sus concentraciones plasmáticas en el tiempo, las que deben centrarse en un rango efectivo y de máxima seguridad


Assuntos
Anti-Infecciosos
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