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1.
bioRxiv ; 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36824711

RESUMO

Mitochondrial quality control is critical for cardiac homeostasis as these organelles are responsible for generating most of the energy needed to sustain contraction. Dysfunctional mitochondria are normally degraded via intracellular degradation pathways that converge on the lysosome. Here, we identified an alternative mechanism to eliminate mitochondria when lysosomal function is compromised. We show that lysosomal inhibition leads to increased secretion of mitochondria in large extracellular vesicles (EVs). The EVs are produced in multivesicular bodies, and their release is independent of autophagy. Deletion of the small GTPase Rab7 in cells or adult mouse heart leads to increased secretion of EVs containing ubiquitinated cargos, including intact mitochondria. The secreted EVs are captured by macrophages without activating inflammation. Hearts from aged mice or Danon disease patients have increased levels of secreted EVs containing mitochondria indicating activation of vesicular release during cardiac pathophysiology. Overall, these findings establish that mitochondria are eliminated in large EVs through the endosomal pathway when lysosomal degradation is inhibited.

2.
In. Faculty of Medical Sciences, The University of the West Indies. 2020 National Health Research Conference: Advancing Health Research in Trinidad and Tobago. Port of Sapin, Caribbean Medical Journal, November 19, 2020. .
Não convencional em Inglês | MedCarib | ID: biblio-1353821

RESUMO

This study aims to test the knowledge, practices & attitudes of drivers in Trinidad through issuing a questionnaire based on driving practices in relation to seat belt use, alcohol consumption, fatigue & distraction, and a quiz, which focuses on road regulations. The information obtained from this study can be used to prevent accidents by identifying: poor knowledge, driving practices and attitudes in the driving population of Trinidad.


Assuntos
Humanos , Cintos de Segurança , Trinidad e Tobago , Atitude , Conhecimento
3.
In. The University of the West Indies, Faculty of Medical Sciences. Faculty of Medical Sciences, Research Day. St. Augustine, Caribbean Medical Journal, March 21, 2019. .
Não convencional em Inglês | MedCarib | ID: biblio-1046261

RESUMO

Objective: To compare biomedical research productivity among selected CARICOM countries. Design and Methodology: Biomedical publications of the selected CARICOM countries (Bahamas, Barbados, Dominica, Guyana, Grenada, Haiti, Jamaica, Suriname, and Trinidad & Tobago) were retrieved using 'PubMed' and 'ScImago Journal & country Rank' (SJR) databases. The publications for each country were then normalized by factors such as total population, gross domestic product (GDP) and Internet usage rate. Results: Total number of papers published by all 9 countries was 7,281 and 8,378 in PubMed (1990- 2015) and SJR databases (1996-2017) respectively. Jamaica produced highest number of biomedical publications [PubMed: 3,928 (54%) and SJR: 2,850 (34%)]. However, when adjusted, Grenada had the highest research publications per million populations, per billion GDP and per 1,000 Internet users in both databases. For trend analysis, PubMed showed that Jamaica produced highest number of additional publications each year ­ on an average 4.8 followed by Trinidad & Tobago (4.4). According to SJR, Jamaica had also highest number of citations (42,311) and H-index (76) followed by Trinidad & Tobago (29,152 and 71). Barbados had the highest number of citations per document (24.9) followed by Haiti (18.4). Conclusion: There was a marked imbalance noted among the CARICOM countries in terms of biomedical research and publications. A CARICOM-wide research may be embarked to explore disparities in biomedical research productivity and thus formulate informed health policies to alleviate diseases and eradicate poverty.


Assuntos
Pesquisa Biomédica , Suriname , Bahamas , Trinidad e Tobago , Barbados , Região do Caribe/etnologia , Dominica , Guiana , Haiti , Jamaica
4.
In. The University of the West Indies, Faculty of Medical Sciences. Faculty of Medical Sciences, Research Day. St. Augustine, Caribbean Medical Journal, March 21, 2019. .
Não convencional em Inglês | MedCarib | ID: biblio-1022138

RESUMO

Objective: The School of Dentistry introduced an Objective Structured Clinical Examination (OSCE) in 2014 for Year 3 students in its Doctor of Dental Surgery (DDS) programme, designed to ensure patient care competency. The objective of the study was to determine student and examiner perceptions of thedental OSCE which takes place in Year 3 Semester I. Design and Methodology: All year 3 dental students (n=27) and examiners (n=14) took part in the study. Following ethical approval, a cross-sectional survey method was used. Data were collected on structured questionnaires administered to students and examiners to obtain their perceptions of the OSCE stations which included: History taking, Examination of a patient, Radiographic examination, Basic Life Support and six other specialty stations. Results: Student survey: Fifteen (15) students (55.6%) agreed that the OSCE was fair and 73.1% agreed they were well organized. However, only 55.6% thought there was sufficient time. Nearly 75% felt the OSCE was representative of real clinical scenarios but only 48.1% agreed it was valid in terms of assessing clinical competence. Examiner Survey: Nearly 93% of examiners thought their OSCE station was well organized and that the time allocated was sufficient. One hundred percent (100%) agreed that their OSCE station was fair, a good assessment of the students' competency to begin seeing patients and that the OSCE was a valid form of assessing clinical competence. Conclusion: While less than half of students thought that the OSCE was valid in terms of assessing clinical competence, all of the Examiners thought that it was valid. The discrepancy between student and examiner perceptions needs further investigation.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Estudantes de Odontologia , Percepção , Trinidad e Tobago
5.
Artigo em Inglês | MedCarib | ID: biblio-1368597

RESUMO

Objective: The objective of this study was to evaluate employers' and graduates' perceptions of the competence of dental graduates from the School of Dentistry, University of the West Indies (UWI). Method: Anonymous questionnaires were sent to employers of the dental graduates in 2013. Similar questionnaires were also completed by graduates of the class of 2011 and 2012. Respondents were asked to rate employees or self assess the UWI School of Dentistry (SoD) curriculum's 23 competency areas and 6 domains of dental practice including: professionalism, assessment of a patient, establishment and maintenance of oral health. Results: Response rates of 48.3%, 100% and 95.7% were obtained from the employers, class of 2011 and class of 2012 respectively. The graduates' self-rated competency means were satisfactory or higher (better) in all competency areas. Employers rated the competency of UWI graduates higher than average in all competency areas except temporomandibular joint/occlusion therapy, orthodontic therapy and dental office administration. Overall, the graduates consistently rated themselves significantly higher than the employers except for periodontal therapy, minor oral surgery, removable prosthodontics and dental office administration. The graduating class of 2011 rated themselves significantly higher than class of 2012 in most (15 out of 23) competency areas. Conclusion: Employers and graduates rated UWI dental graduate competency above average in all areas except orthodontics and dental office administration. UWI dental graduates have a better perception of their competency than do their employers. The School of Dentistry needs to pay particular attention to the areas highlighted and review the curriculum accordingly.


Assuntos
Humanos , Região do Caribe , Odontologia , Ortodontia , Faculdades de Odontologia , Consultórios Odontológicos
6.
West Indian Med J ; 63(2): 159-66, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25303251

RESUMO

OBJECTIVE: To explore the emotional intelligence (EI) in medical students in a Caribbean medical school and investigate its association with gender, age, year of study and ethnicity. DESIGN AND METHODS: A cross-sectional design using convenient sampling of 304 years two to five undergraduate medical students at the School of Medicine, the University of the West Indies (UWI), St Augustine campus, was conducted. The Mayer-Salovey-Caruso Emotional Intelligence Test (MSCEIT-V2.0) was administered to test four branches of EI: perceiving emotions, facilitating thought, understanding emotions and managing emotions. Data were analysed using SPSS version 19. T-test, analysis of variance (ANOVA) and r (product moment correlation) were calculated to establish the effects of selected variables (gender, age, year of study and ethnicity) on total and sub-scales EI scores and tested against 0.05 and 0.01 significance levels. RESULTS: The total mean score for EI fell within the average according to MSCEIT standards. Gender analysis showed significantly higher scores for males and for younger age groups (< 25 years). Year of study and ethnicity did not yield any significant effect. CONCLUSIONS: These findings of higher EI scores in males and younger students are unusual, given the well-publicized stereotype of the Caribbean male and the perception that advancing age brings maturity and emotional stability. It would be valuable to widen this study by including other UWI campuses and offshore medical schools in the Caribbean. This preliminary study examined a sample of medical students from a well-established Caribbean medical school. Since EI is considered to be important in the assessment and training of medical undergraduates, consideration should be given to introducing interventions aimed at increasing EI.

7.
Interação psicol ; 16(2): 327-337, jul.-dez. 2012.
Artigo em Português | Index Psicologia - Periódicos | ID: psi-57101

RESUMO

Estudo teórico que analisa as diferentes perspectivas de aquisição da linguagem escrita: tradicional, construtivista psicogenética, métodos fônicos e letramento. O referencial de análise é a concepção de alfabetizar letrando, na qual a alfabetização (domínio do sistema gráfico) e o letramento (uso da leitura e da escrita nas diversas funções sociais) são trabalhadas conjuntamente. Uma segunda análise destaca três momentos da formação de alfabetizadores: o tradicional, o construtivista e a tentativa de superação destas duas abordagens. Os resultados do estudo evidenciaram o afastamento das diversas perspectivas metodológicas da concepção de alfabetizar letrando e a necessidade da formação de alfabetizadores considerar a alfabetização e o letramento como ações indissociáveis (AU)


A theoretical study which analyses the different perspectives of the acquisition of written language: the traditional method, the psycogenetic constructivism, the phonic methods and the whole language approach. The parameter for analysis is the assumption of literacy through the whole language approach in which learning to read and write (mastering the graphic system) and literacy (appropriate use of reading and writing in different social functions) are developed together. A second analysis points out three moments in the preparation of teachers: the traditional, the constructivist and finally the attempt to overcome these two perspectives. The results of the study point out that there is a gap between these three methodological perspectives and the notion of preparing teachers who consider that mastering the graphic system and becoming competent users of language in its several social functions are inseparable teaching actions (AU)


Assuntos
Educação , Docentes
8.
Interaçao psicol ; 16(2): 327-337, jul.-dez. 2012.
Artigo em Português | LILACS | ID: lil-680281

RESUMO

Estudo teórico que analisa as diferentes perspectivas de aquisição da linguagem escrita: tradicional, construtivista psicogenética, métodos fônicos e letramento. O referencial de análise é a concepção de alfabetizar letrando, na qual a alfabetização (domínio do sistema gráfico) e o letramento (uso da leitura e da escrita nas diversas funções sociais) são trabalhadas conjuntamente. Uma segunda análise destaca três momentos da formação de alfabetizadores: o tradicional, o construtivista e a tentativa de superação destas duas abordagens. Os resultados do estudo evidenciaram o afastamento das diversas perspectivas metodológicas da concepção de alfabetizar letrando e a necessidade da formação de alfabetizadores considerar a alfabetização e o letramento como ações indissociáveis.


A theoretical study which analyses the different perspectives of the acquisition of written language: the traditional method, the psycogenetic constructivism, the phonic methods and the whole language approach. The parameter for analysis is the assumption of literacy through the whole language approach in which learning to read and write (mastering the graphic system) and literacy (appropriate use of reading and writing in different social functions) are developed together. A second analysis points out three moments in the preparation of teachers: the traditional, the constructivist and finally the attempt to overcome these two perspectives. The results of the study point out that there is a gap between these three methodological perspectives and the notion of preparing teachers who consider that mastering the graphic system and becoming competent users of language in its several social functions are inseparable teaching actions.


Assuntos
Educação , Docentes
9.
West Indian Med J ; 61(2): 180-6, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23155967

RESUMO

OBJECTIVE: This prospective cross-sectional study was undertaken to determine the normative and perceived orthodontic treatment needs of children aged 11-12 years in a Caribbean country, Trinidad and Tobago. METHODS: One author, an experienced orthodontist, examined 367 children using the Dental Health Component (DHC) of the Index of Orthodontic Treatment Need (IOTN) to assess the normative need. The same orthodontist administered the questionnaire to assess the patient's perceived needs using the Aesthetic Component (AC) of the IOTN and the Oral Aesthetic Subjective Impact Scale (OASIS). RESULTS: The DHC and the AC of the IOTN and the OASIS showed respectively that 61.4%, 2.5% and 0.6% of the children had definite need for orthodontic treatment. The female proportion of the sample was more than the target population but the perceived need and normative need for orthodontic treatment did not depend significantly (p < 0.05) on the gender or ethnicity of the subjects of this study. The perception of need for orthodontic treatment differed inversely from the normative need and this is seen to be significant (p < 0.05) when OASIS was used. CONCLUSIONS: Approximately three out of five children in Trinidad and Tobago have a great (or very great) need for orthodontic treatment for dental health reasons.


Assuntos
Índice de Necessidade de Tratamento Ortodôntico , Má Oclusão/epidemiologia , Criança , Feminino , Humanos , Masculino , Má Oclusão/diagnóstico , Má Oclusão/terapia , Trinidad e Tobago/epidemiologia
10.
West Indian med. j ; 61(2): 180-186, Mar. 2012. graf, tab
Artigo em Inglês | LILACS | ID: lil-672878

RESUMO

OBJECTIVE: This prospective cross-sectional study was undertaken to determine the normative and perceived orthodontic treatment needs of children aged 11-12 years in a Caribbean country, Trinidad and Tobago. METHODS: One author, an experienced orthodontist, examined 367 children using the Dental Health Component (DHC) of the Index of Orthodontic Treatment Need (IOTN) to assess the normative need. The same orthodontist administered the questionnaire to assess the patient's perceived needs using the Aesthetic Component (AC) of the IOTN and the Oral Aesthetic Subjective Impact Scale (OASIS). RESULTS: The DHC and the AC of the IOTN and the OASIS showed respectively that 61.4%, 2.5% and 0.6% of the children had definite need for orthodontic treatment. The female proportion of the sample was more than the target population but the perceived need and normative need for orthodontic treatment did not depend significantly (p < 0.05) on the gender or ethnicity of the subjects of this study. The perception of need for orthodontic treatment differed inversely from the normative need and this is seen to be significant (p < 0.05) when OASIS was used. CONCLUSIONS: Approximately three out of five children in Trinidad and Tobago have a great (or very great) need for orthodontic treatment for dental health reasons.


OBJETIVO: Este estudio prospectivo transversal fue emprendido con el objeto de determinar las necesidades del tratamiento ortodóntico normativo y percibido para niños de 11-12 años de edad en un país caribeño - Trinidad y Tobago. MÉTODOS: Un autor - ortodoncista experimentado - examinó a 367 niños usando el Componente de Salud Dental (DHC) del Índice de Necesidad del Tratamiento Ortodóntico (IOTN) para evaluar la necesidad normativa. El mismo ortodoncista aplicó la encuesta para evaluar las necesidades percibidas del paciente usando el Componente Estético (CA) del IOTN y Escala ortodóntica de impacto estético subjetivo (OASIS). RESULTADOS: El DHCy el CA del IOTNy el OASIS mostraron respectivamente que 61.4%, 2.5% y .6% de los ninos tenían una necesidad definida de tratamiento ortodóntico. La proporción de hembras de la muestra fue mayor que la población objetivo, pero la necesidad percibida y la necesidad normativa de tratamiento ortodóntico no dependia significativamente (p < 0.05) del género o etnicidad de los sujetos de este estudio. La percepción de la necesidad de tratamiento ortodóntico difería inversamente de la necesidad normativa y puede verse que es significativa (p < 0.05) cuando el OASIS fue usado. CONCLUSIONES: Aproximadamente tres de cada cinco ninos en Trinidad y Tobago tienen una necesidad grande (o muy grande) de tratamiento ortodóntico por razones de salud dental.


Assuntos
Criança , Feminino , Humanos , Masculino , Índice de Necessidade de Tratamento Ortodôntico , Má Oclusão/epidemiologia , Má Oclusão/diagnóstico , Má Oclusão/terapia , Trinidad e Tobago/epidemiologia
11.
Work ; 41 Suppl 1: 5935-42, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22317729

RESUMO

This paper aims to present an ergonomic device to assist in the maintenance of the units of Tucuruí Hydropower Plant. The development of this ergonomic device made possible to reduce maintenance time, reduce losses caused by billing, improve performance and reduce the physical strain for labors during the execution of services.


Assuntos
Ergonomia/instrumentação , Centrais Elétricas , Gestão de Riscos , Análise e Desempenho de Tarefas , Gestão da Qualidade Total , Brasil , Monitoramento Ambiental , Ergonomia/economia , Humanos , Doenças Profissionais/prevenção & controle , Saúde Ocupacional/normas , Esforço Físico , Fatores de Tempo
12.
Work ; 41 Suppl 1: 2822-30, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22317147

RESUMO

This paper aims to present the benefits achieved in the ergonomics process management with the use of the TPM methodology (Total Productive Maintenance) in Tucuruí Hydropower Plant. The methodology is aligned with the corporate guidelines, moreover with the Strategic Planning of the company, it is represented in the TPM Pillars including the Health Pillar in which is inserted the ergonomics process. The results of the ergonomic actions demonstrated a 12% reduction over the absenteeism rate due to musculoskeletal disorders, solving 77,0% of ergonomic non-conformities, what favored the rise of the Organizational Climate in 44,8%, impacting on the overall performance of the company. Awards confirmed the success of the work by the achievement of the Award for TPM Excellence in 2001, Award for Excellence in Consistent TPM Commitment in 2009 and more recently the Special Award for TPM Achievement, 2010. The determination of the high rank administration and workers, allied with the involvement/dynamism of Pillars, has assured the success of this management practice in Tucuruí Hydropower Plant.


Assuntos
Ergonomia/métodos , Saúde Ocupacional , Centrais Elétricas , Brasil , Humanos , Cultura Organizacional , Objetivos Organizacionais , Política Organizacional
13.
Clinics (Sao Paulo) ; 66(3): 493-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21552679

RESUMO

Atypical Mole Syndrome is the most important phenotypic risk factor for developing cutaneous melanoma, a malignancy that accounts for about 80% of deaths from skin cancer. Because the diagnosis of melanoma at an early stage is of great prognostic relevance, the identification of Atypical Mole Syndrome carriers is essential, as well as the creation of recommended preventative measures that must be taken by these patients.


Assuntos
Síndrome do Nevo Displásico/complicações , Melanoma/etiologia , Neoplasias Cutâneas/etiologia , Diagnóstico Diferencial , Síndrome do Nevo Displásico/patologia , Diagnóstico Precoce , Humanos , Melanoma/patologia , Fatores de Risco , Neoplasias Cutâneas/patologia
14.
PDA J Pharm Sci Technol ; 62(2): 125-54, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18540538

RESUMO

In the last couple of decades, use of biodegradable polymer-based microspheres has been recognized as an interesting and promising approach for parenteral controlled delivery of therapeutic peptide/protein, including antigens. The main objectives of this review are (i) to update the current state of art of manufacturing of peptide/protein-loaded microspheres through both conventional and newer microencapsulation techniques, and (ii) to bring into focus the various possible instability problems, and the investigated mechanistic ways to obviate the instability problems of peptide/protein drug during microspheres preparation as well as its release from the microspheres. The solubilization, stabilization, and preservation enhancing excipients that are used in peptide/protein-loaded microspheres are briefly overviewed.


Assuntos
Microesferas , Peptídeos/administração & dosagem , Proteínas/administração & dosagem , Química Farmacêutica , Preparações de Ação Retardada , Estabilidade de Medicamentos , Excipientes/química , Injeções , Peptídeos/química , Polímeros/química , Proteínas/química , Tecnologia Farmacêutica/métodos
15.
Indian J Pharm Sci ; 70(2): 180-5, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-20046709

RESUMO

Aceclofenac, a non-steroidal antiinflammatory drug, is used for posttraumatic pain and rheumatoid arthritis. Aceclofenac fast-dispersible tablets have been prepared by direct compression method. Effect of superdisintegrants (such as, croscarmellose sodium, sodium starch glycolate and crospovidone) on wetting time, disintegration time, drug content, in vitro release and stability parameters has been studied. Disintegration time and dissolution parameters (t(50%) and t(80%)) decreased with increase in the level of croscarmellose sodium. Where as, disintegration time and dissolution parameters increased with increase in the level of sodium starch glycolate in tablets. However, the disintegration time values did not reflect in the dissolution parameter values of crospovidone tablets and release was dependent on the aggregate size in the dissolution medium. Stability studies indicated that tablets containing superdisintegrants were sensitive to high humidity conditions. It is concluded that fast-dispersible aceclofenac tablets could be prepared by direct compression using superdisintegrants.

16.
J Microencapsul ; 23(8): 899-911, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17390631

RESUMO

Propranolol-HCl, a water soluble drug, was bound to Indion 254, a cation exchange resin, and the resulting resinate was microencapsulated with polystyrene using an oil-in-water emulsion-solvent evaporation method with a view to achieve prolonged drug release in simulated gastric and intestinal fluid. The effect of various formulation parameters on the characteristics of the microcapsules was studied. The diameter of the resinate-loaded polystyrene microcapsules increased with increase in the concentration of emulsion stabilizer and coat/core ratio and decreased with increase in the volume of organic disperse phase. The variation in the size of the microcapsules appeared to be related with the inter-facial viscosity which was influenced by the viscosity of both the aqueous dispersion medium and the organic disperse phase. The resinate encapsulation efficiency and hence the drug entrapment efficiency of the microcapsules increased with increase in the concentration of emulsion stabilizer and coat/core ratio and decreased with increase in the volume of organic disperse phase. These characteristics were found to depend on the extent of formation of fractured microcapsules and subsequent partitioning of the resinate into the aqueous dispersion medium. The degree of fracture on the microcapsules depended on the viscosity of the aqueous dispersion medium and the organic disperse phase. The uncoated resinate discharged the drug quite rapidly following the typical particle diffusion process. Although the desorption of the drug from the resinate was independent of pH of the dissolution media, increase in ionic strength increased the drug desorption. On the other hand, release of drug from the coated resinate was considerably prolonged and followed a diffusion controlled model. The prolongation of drug release was dependent on the uniformity of coating which was influenced by the formulation parameters. The drug release from the microcapsules was also found to be independent of pH of the dissolution media and increased with increase in ionic strength. The pH-independent release of the drug from both the uncoated and microencapsulated resinate was due to pH-independent solubility of the drug and high equilibrium concentration of the resinate in both the dissolution media. Polystyrene appeared to be a suitable polymer to provide prolonged release of propranolol independent of pH of the dissolution media.


Assuntos
Resinas de Troca Iônica/química , Poliestirenos/química , Propranolol/química , Cápsulas , Microscopia Eletrônica de Varredura
17.
Int J Pharm ; 302(1-2): 84-94, 2005 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-16102927

RESUMO

Propranolol-HCl-loaded calcium alginate (ALG) beads, propranolol-resin complex (resinate)-loaded calcium alginate (RALG) beads and polyethyleneimine (PEI)-treated RALG (RALG-PEI) beads were prepared by ionotropic gelation/polyelectrolyte complexation method. The beads were evaluated and compared in respect of drug entrapment efficiency (DEE) and release characteristics in simulated gastric fluid (SGF, 0.1(N) HCl, pH 1.2) and simulated intestinal fluid (SIF, phosphate buffer, pH 6.8). DEE of RALG beads was considerably higher than that of ALG beads containing unresinated drug. However, DEE of RALG beads decreased with increase in both gelation time and concentration of the gel forming Ca2+ ions due to drug displacement from resinate. PEI treatment of RALG beads further decreased DEE as the polycation also displaced the drug from the resinate. The release of drug from all the beads was slow and incomplete in SGF owing to considerably less swelling of the beads and the decrease in drug release from the beads followed the order: RALG-PEI

Assuntos
Alginatos/química , Sistemas de Liberação de Medicamentos/métodos , Microesferas , Polietilenoimina/química , Propranolol/farmacocinética , Anti-Hipertensivos/química , Anti-Hipertensivos/farmacocinética , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Concentração de Íons de Hidrogênio , Secreções Intestinais/metabolismo , Cinética , Microscopia Eletrônica de Varredura , Porosidade , Propranolol/química , Solubilidade , Tecnologia Farmacêutica/métodos
18.
J Microencapsul ; 22(1): 67-80, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16019892

RESUMO

The objective of this investigation is to develop a multi-unit sustained release dosage form of a water soluble drug from a completely aqueous environment avoiding the use of any organic solvent. The drug was complexed with resin and calcium alginate or polyethyleneimine-treated calcium alginate beads loaded with the resinate were prepared by a ionic/polyelectrolyte complexation method. The effect of different formulation variables on the characteristics of the beads was investigated. Although the drug release from spherical and smooth-surfaced calcium alginate beads in both acidic and alkaline dissolution media were slower than those obtained from plain resinate, none of the variables were found to prolong the drug release considerably due to rapid swelling and disintegration of calcium alginate beads in alkaline medium. On the other hand, drug release from polyethyleneimine-treated calcium alginate beads in acidic medium did not increase appreciably following a burst release. However, in alkaline medium, the drug release was found to increase gradually and extend over a different period of time depending on the intensity of polyethyleneimine treatment. Scanning electron micrographs revealed the formation of a dense membrane around the resinate-loaded calcium alginate matrix. The membrane appeared to be responsible for reduced swelling and protracted disintegration of the beads resulting in slow release of the drug. The results indicate that sustained release of a water soluble drug from polyethyleneimine-treated calcium alginate beads could be achieved by adjusting the formulation variables.


Assuntos
Alginatos , Diltiazem , Composição de Medicamentos/métodos , Microesferas , Polietilenoimina , Materiais Biocompatíveis , Cloreto de Cálcio/farmacologia , Resinas de Troca de Cátion , Preparações de Ação Retardada , Diltiazem/farmacocinética , Ácido Glucurônico , Ácidos Hexurônicos , Microscopia Eletrônica de Varredura , Polietilenoimina/análise , Propriedades de Superfície , Fatores de Tempo
19.
J Chemother ; 14(1): 47-53, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11892899

RESUMO

The antiinflammatory agent diclofenac sodium (Dc) exhibited remarkable antibacterial effects both in vitro and in vivo. Fifteen different bacteria sensitive to Dc as well as to a number of common antibiotics were tested for synergistic effects in vitro. Disc diffusion test with Dc and aminoglycosides assessed by stringent computation showed clear-cut synergism. Synergism between Dc and streptomycin (Sm) was found to be statistically significant (p < or = 0.01) when compared with their individual effects. By the checkerboard assessment procedure, the fractional inhibitory concentration (FIC) index of this combination was found to be 0.49, confirming synergism. The mouse protective capacity of this combination was then evaluated in vivo against S. typhimurium as the virulent infecting bacterium, and the size of bacterial load determined from infected autopsied animals. Statistical analysis by Student's 't' test suggested this drug combination is highly synergistic; synergism was also noted between Dc and other aminoglycosides.


Assuntos
Antibacterianos/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Bactérias/efeitos dos fármacos , Diclofenaco/farmacologia , Aminoglicosídeos , Animais , Sinergismo Farmacológico , Camundongos , Testes de Sensibilidade Microbiana , Salmonelose Animal/tratamento farmacológico
20.
Boll Chim Farm ; 140(6): 462-6, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11822240

RESUMO

Theophylline loaded conventional suppositories, sustained release matrix suppositories and sustained release two layered suppositories were prepared using polyethylene glycol 4000 and eudragit RS-100 and their characteristics were evaluated both in-vitro and in-vivo. In comparison to conventional suppositories, the release of the drug from sustained release matrix suppositories was gradual and extended over a period of time. On the other hand two layered suppositories produced an initial quick release followed by extended release of the drug. The in-vivo results were found to correlate with the in-vitro results.


Assuntos
Broncodilatadores/química , Teofilina/química , Animais , Broncodilatadores/administração & dosagem , Preparações de Ação Retardada , Excipientes , Masculino , Coelhos , Solubilidade , Supositórios , Teofilina/administração & dosagem
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