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1.
Tech Coloproctol ; 27(12): 1251-1256, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37106220

RESUMO

PURPOSE: A protective loop ileostomy is the most useful method to reduce sequelae in the event of an anastomotic leakage (AL) after rectal cancer surgery. However, it requires an additional stoma reversal surgery with its own potential complications. Postoperative ileus (POI) remains the most common complication after ileostomy reversal, which leads to an increase in morbidity, length of hospital stay (LOS) and overall healthcare costs. Several retrospective studies carried out in this field have concluded that there are insufficient evidence-based recommendations about the routine application of preoperative bowel stimulation in clinical practice. Here we discuss whether stimulation of the efferent limb before ileostomy reversal might reduce POI and improve postoperative outcomes. METHODS: This is a multicentre randomised controlled trial to determine whether mechanical stimulation of the efferent limb during the 2 weeks before the ileostomy reversal would help to reduce the development of POI after surgery. This study was registered on Clinicaltrials.gov (NCT05302557). Stimulation will consist of infusing a solution of 500 ml of saline chloride solution mixed with a thickening agent (Resource©, Nestlé Health Science; 6.4 g sachet) into the distal limb of the ileostomy loop. This will be performed within the 2 weeks before ileostomy reversal, in an outpatient clinic under the supervision of a trained stoma nurse. CONCLUSION: The results of this study could provide some insights into the preoperative management of these patients.


Assuntos
Íleus , Neoplasias Retais , Humanos , Ileostomia/efeitos adversos , Ileostomia/métodos , Estudos Retrospectivos , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Fístula Anastomótica/etiologia , Neoplasias Retais/cirurgia , Neoplasias Retais/complicações , Reto , Íleus/etiologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como Assunto
5.
Ann Oncol ; 30(8): 1311-1320, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31086949

RESUMO

BACKGROUND: Although EGFR mutant tumors exhibit low response rates to immune checkpoint blockade overall, some EGFR mutant tumors do respond to these therapies; however, there is a lack of understanding of the characteristics of EGFR mutant lung tumors responsive to immune checkpoint blockade. PATIENTS AND METHODS: We retrospectively analyzed de-identified clinical and molecular data on 171 cases of EGFR mutant lung tumors treated with immune checkpoint inhibitors from the Yale Cancer Center, Memorial Sloan Kettering Cancer Center, University of California Los Angeles, and Dana Farber Cancer Institute. A separate cohort of 383 EGFR mutant lung cancer cases with sequencing data available from the Yale Cancer Center, Memorial Sloan Kettering Cancer Center, and The Cancer Genome Atlas was compiled to assess the relationship between tumor mutation burden and specific EGFR alterations. RESULTS: Compared with 212 EGFR wild-type lung cancers, outcomes with programmed cell death 1 or programmed death-ligand 1 (PD-(L)1) blockade were worse in patients with lung tumors harboring alterations in exon 19 of EGFR (EGFRΔ19) but similar for EGFRL858R lung tumors. EGFRT790M status and PD-L1 expression did not impact response or survival outcomes to immune checkpoint blockade. PD-L1 expression was similar across EGFR alleles. Lung tumors with EGFRΔ19 alterations harbored a lower tumor mutation burden compared with EGFRL858R lung tumors despite similar smoking history. CONCLUSIONS: EGFR mutant tumors have generally low response to immune checkpoint inhibitors, but outcomes vary by allele. Understanding the heterogeneity of EGFR mutant tumors may be informative for establishing the benefits and uses of PD-(L)1 therapies for patients with this disease.


Assuntos
Antineoplásicos Imunológicos/farmacologia , Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Idoso , Alelos , Antineoplásicos Imunológicos/uso terapêutico , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/imunologia , Antígeno B7-H1/metabolismo , Biomarcadores Tumorais/antagonistas & inibidores , Biomarcadores Tumorais/metabolismo , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/imunologia , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/genética , Receptores ErbB/metabolismo , Feminino , Heterogeneidade Genética , Humanos , Pulmão/imunologia , Pulmão/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Mutação , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/imunologia , Receptor de Morte Celular Programada 1/metabolismo , Intervalo Livre de Progressão , Estudos Retrospectivos , Fumar Tabaco/efeitos adversos , Fumar Tabaco/epidemiologia
6.
JDR Clin Trans Res ; 4(4): 360-370, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31009578

RESUMO

INTRODUCTION: Patients with rheumatoid arthritis (RA) present a higher incidence and severity of periodontitis than the general population. Our study, Outcomes of Periodontal Treatment in Patients with Rheumatoid Arthritis (OPERA), was a randomized waiting-list controlled trial using mixed methods. Patients randomized to the intervention arm received intensive periodontal treatment, and those in the control arm received the same treatment with a 6-mo delay. AIM: The nested qualitative component aimed to explore patients' experiences and priorities concerning oral health and barriers and facilitators for trial participation. METHODS: Using purposive sampling until thematic saturation was reached, we conducted 21 one-to-one semistructured interviews with randomized patients in either of the 2 treatment arms as well as with patients who did not consent for trial participation. RESULTS: The patients described their experiences about RA, oral health, and study participation. Previous experiences with dental care professionals shaped patients' current perceptions about oral health and the place of oral health on their list of priorities compared with other conditions. Patients also highlighted some of the barriers and facilitators for study participation and for compliance with oral health maintenance. The patients, in the control arm, presented their views regarding the acceptable length of waiting time for the intervention. CONCLUSION: The associations between periodontal and systemic health are increasingly recognized by the literature. Our study provided an insight into RA patients' experiences and perceptions about oral health. It also highlighted some of the barriers and facilitators for participating in a periodontal interventional study for this group. We hope that our findings will support the design of larger interventional periodontal studies in patients with RA. The complex challenges faced by the burden of RA and the associated multimorbidities in this patient group might highlight opportunities to improve access to oral health services in this patient population. KNOWLEDGE TRANSFER STATEMENT: This article provided insights into the experiences and perceptions of rheumatoid arthritis patients about their oral health to improve patient participation in a definitive clinical trial.


Assuntos
Artrite Reumatoide , Periodontite , Atitude , Humanos , Saúde Bucal , Pesquisa Qualitativa
7.
Ann Oncol ; 29(7): 1509-1520, 2018 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-29790899

RESUMO

Of the solid tumor types that metastasize to the brain, melanoma has the highest propensity to form brain metastases. In addition, much remains unknown regarding the pathophysiology involved in melanoma cell extravasation through the blood-brain barrier, which enables interactions with the microenvironment, and melanoma cell transcriptomic responses to brain-specific cues. However, recent developments in targeted therapy and immunotherapy have generated considerable optimism regarding the treatment of metastatic melanoma. Although robust efficacy data exist on systemic therapy treatment of extracranial melanoma, data in the setting of melanoma brain metastases (MBM) are limited, primarily because patients with MBM are typically excluded from clinical trials. However, several clinical trials focusing on patients with MBM are now complete, and more are underway. Clinical evaluation of serine/threonine-protein kinase B-Raf inhibition in combination with MEK inhibition for MBM produced intracranial response rates of close to 60%, suggesting that inhibition of the mitogen-activated protein kinase pathway has the potential to further improve MBM outcomes. For immunotherapy, there is now increasing evidence that checkpoint inhibitors may also be effective in MBM with a high rate of durable intracranial responses observed with combination therapy. Furthermore, radiotherapy-particularly MBM treatment with mainstay stereotactic radiosurgery-appears to be safe and effective when combined with systemic therapy. Finally, evolving magnetic resonance imaging capabilities have inspired new approaches to the measurement of tumor burden and treatment responses. This review evaluates current published evidence describing MBM as a multifaceted disease and presents an overview of currently available and investigational treatments for patients with MBM.


Assuntos
Neoplasias Encefálicas/terapia , Melanoma/terapia , Neoplasias Encefálicas/secundário , Terapia Combinada , Humanos , Melanoma/patologia , Prognóstico
8.
Med. intensiva (Madr., Ed. impr.) ; 41(6): 368-376, ago.-sept. 2017. ilus, tab, graf
Artigo em Espanhol | IBECS | ID: ibc-165511

RESUMO

Los análisis aleatorios de seguridad en tiempo real son una herramienta que ha sido creada como un método de traslación del conocimiento desde las fuentes de la evidencia científica hasta la cabecera del paciente. Ha demostrado ser útil en el entorno del paciente crítico, en términos de mejora de la seguridad en el proceso de cuidados al paciente crítico, transformando situaciones inseguras en seguras en el día a día, garantizando la adherencia a la evidencia científica. Paralelamente, por su diseño y metodología ha permitido disponer de indicadores de proceso que hará posible conocer cómo realizamos la atención a nuestros pacientes, la evolución en el tiempo (y el feedback periódico a los profesionales), el impacto de nuestras intervenciones y el benchmarking (AU)


Real-time random safety audits constitute a tool designed to transfer knowledge from the sources of scientific evidence to the patient bedside. It has proven useful in critically ill patients, improving safety in the process of critical patient care, turning unsafe situations into safe ones in daily practice, and ensuring adherence to scientific evidence. In parallel, the design and methodology involved affords process indicators that will make it possible to know how we provide care for our patients, evolution over time (with regular feedback for professionals), the impact of our interventions, and benchmarking (AU)


Assuntos
Humanos , Cuidados Críticos/métodos , Segurança do Paciente/normas , Processos Estocásticos , Interpretação Estatística de Dados , Unidades de Terapia Intensiva/organização & administração , Gestão da Segurança , Auditoria Administrativa , Governança Clínica
9.
Rev Med Chil ; 145(3): 393-396, 2017 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-28548198

RESUMO

Diabetic ketoacidosis with mild hyperglycemia is a major complication of sodium-glucose cotransporter 2 inhibitors. Although its use is not approved for patients with type 1 diabetes mellitus, the drug is often prescribed with the hope of optimizing metabolic control. We report a 20 years old female with hypothyroidism and type 1 diabetes consulting for vomiting and abdominal pain. The patient had used canagliflozin during the two previous months. Laboratory showed a blood glucose of 200 mg/dl, a severe metabolic acidosis (pH 7.1) and ketonemia. The patient was successfully treated in the intensive care unit.


Assuntos
Canagliflozina/efeitos adversos , Cetoacidose Diabética/induzido quimicamente , Hiperglicemia/induzido quimicamente , Hipoglicemiantes/efeitos adversos , Adulto , Canagliflozina/uso terapêutico , Diabetes Mellitus Tipo 1/tratamento farmacológico , Cetoacidose Diabética/diagnóstico , Feminino , Humanos , Hiperglicemia/diagnóstico , Hipoglicemiantes/uso terapêutico , Inibidores do Transportador 2 de Sódio-Glicose
10.
Leukemia ; 31(12): 2642-2651, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28439107

RESUMO

Multiple myeloma (MM) is characterized by the clonal expansion and metastatic spread of malignant plasma cells to multiple sites in the bone marrow (BM). Recently, we implicated the sialyltransferase ST3Gal-6, an enzyme critical to the generation of E-selectin ligands, in MM BM homing and resistance to therapy. Since E-selectin is constitutively expressed in the BM microvasculature, we wished to establish the contribution of E-selectin ligands to MM biology. We report that functional E-selectin ligands are restricted to a minor subpopulation of MM cell lines which, upon expansion, demonstrate specific and robust interaction with recombinant E-selectin in vitro. Moreover, an increase in the mRNA levels of genes involved in the generation of E-selectin ligands was associated with inferior progression-free survival in the CoMMpass study. In vivo, E-selectin ligand-enriched cells induced a more aggressive disease and were completely insensitive to Bortezomib. Importantly, this resistance could be reverted by co-administration of GMI-1271, a specific glycomimetic antagonist of E-selectin. Finally, we report that E-selectin ligand-bearing cells are present in primary MM samples from BM and peripheral blood with a higher proportion seen in relapsed patients. This study provides a rationale for targeting E-selectin receptor/ligand interactions to overcome MM metastasis and chemoresistance.


Assuntos
Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Selectina E/antagonistas & inibidores , Selectina E/metabolismo , Mieloma Múltiplo/metabolismo , Animais , Bortezomib/farmacologia , Adesão Celular , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Ligantes , Camundongos , Mieloma Múltiplo/genética , Mieloma Múltiplo/mortalidade , Mieloma Múltiplo/patologia , Prognóstico , Ligação Proteica , Recidiva , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Rev. méd. Chile ; 145(3): 393-396, Mar. 2017.
Artigo em Espanhol | LILACS | ID: biblio-845553

RESUMO

Diabetic ketoacidosis with mild hyperglycemia is a major complication of sodium-glucose cotransporter 2 inhibitors. Although its use is not approved for patients with type 1 diabetes mellitus, the drug is often prescribed with the hope of optimizing metabolic control. We report a 20 years old female with hypothyroidism and type 1 diabetes consulting for vomiting and abdominal pain. The patient had used canagliflozin during the two previous months. Laboratory showed a blood glucose of 200 mg/dl, a severe metabolic acidosis (pH 7.1) and ketonemia. The patient was successfully treated in the intensive care unit.


Assuntos
Humanos , Feminino , Adulto , Cetoacidose Diabética/induzido quimicamente , Canagliflozina/efeitos adversos , Hiperglicemia/induzido quimicamente , Hipoglicemiantes/efeitos adversos , Cetoacidose Diabética/diagnóstico , Diabetes Mellitus Tipo 1/tratamento farmacológico , Canagliflozina/uso terapêutico , Inibidores do Transportador 2 de Sódio-Glicose , Hiperglicemia/diagnóstico , Hipoglicemiantes/uso terapêutico
12.
Med Intensiva ; 41(6): 368-376, 2017.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-27776937

RESUMO

Real-time random safety audits constitute a tool designed to transfer knowledge from the sources of scientific evidence to the patient bedside. It has proven useful in critically ill patients, improving safety in the process of critical patient care, turning unsafe situations into safe ones in daily practice, and ensuring adherence to scientific evidence. In parallel, the design and methodology involved affords process indicators that will make it possible to know how we provide care for our patients, evolution over time (with regular feedback for professionals), the impact of our interventions, and benchmarking.


Assuntos
Cuidados Críticos/normas , Auditoria Médica , Segurança do Paciente , Lista de Checagem , Humanos , Unidades de Terapia Intensiva , Erros Médicos/prevenção & controle , Distribuição Aleatória
15.
Neurobiol Dis ; 45(2): 810-20, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22115942

RESUMO

Methamphetamine (METH) is a potent, highly addictive psychostimulant consumed worldwide. In humans and experimental animals, repeated exposure to this drug induces persistent neurodegenerative changes. Damage occurs primarily to dopaminergic neurons, accompanied by gliosis. The toxic effects of METH involve excessive dopamine (DA) release, thus DA receptors are highly likely to play a role in this process. To define the role of D(1) receptors in the neurotoxic effects of METH we used D(1) receptor knock-out mice (D(1)R(-/-)) and their WT littermates. Inactivation of D(1)R prevented METH-induced dopamine fibre loss and hyperthermia, and increases in gliosis and pro-inflammatory molecules such as iNOS in the striatum. In addition, D(1)R inactivation prevented METH-induced loss of dopaminergic neurons in the substantia nigra. To explore the relationship between hyperthermia and neurotoxicity, METH was given at high ambient temperature (29 °C). In this condition, D(1)R(-/-) mice developed hyperthermia following drug delivery and the neuroprotection provided by D(1)R inactivation at 23 °C was no longer observed. However, reserpine, which empties vesicular dopamine stores, blocked hyperthermia and strongly potentiated dopamine toxicity in D(1)R(-/-) mice, suggesting that the protection afforded by D(1)R inactivation is due to both hypothermia and higher stored vesicular dopamine. Moreover, electrical stimulation evoked higher DA overflow in D(1)R(-/-) mice as demonstrated by fast scan cyclic voltammetry despite their lower basal DA content, suggesting higher vesicular DA content in D(1)R(-/-) than in WT mice. Altogether, these results indicate that the D(1)R plays a significant role in METH-induced neurotoxicity by mediating drug-induced hyperthermia and increasing the releasable cytosolic DA pool.


Assuntos
Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Estimulantes do Sistema Nervoso Central/toxicidade , Metanfetamina/toxicidade , Receptores de Dopamina D1/metabolismo , Animais , Encéfalo/metabolismo , Dopamina/metabolismo , Feminino , Febre/genética , Febre/metabolismo , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Knockout , Receptores de Dopamina D1/genética
16.
Monaldi Arch Chest Dis ; 75(4): 220-34, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22462310

RESUMO

Chronic obstructive pulmonary disease (that includes emphysema) results in significant morbidity and mortality worldwide. Idiopathic pulmonary fibrosis (IPF) is also a chronic and progressive parenchymal lung disease with an average survival of less than 5 years after diagnosis. Combined pulmonary fibrosis and emphysema (CPFE) is an important but still underdiagnosed syndrome. Its diagnosis is based on the radiological findings at computed tomography which consists of emphysema of the upper lung zones and fibrosis of the lower lung zones. Since this syndrome has a very bad prognosis, even worse than isolated finding of emphysema or fibrosis alone, early recognition and rapid treatment are important. In this article we will review and elucidate the radiologic appearance of this syndrome and highlight its clinical importance.


Assuntos
Enfisema Pulmonar/diagnóstico por imagem , Enfisema Pulmonar/epidemiologia , Fibrose Pulmonar/diagnóstico por imagem , Fibrose Pulmonar/epidemiologia , Tomografia Computadorizada por Raios X , Humanos , Prognóstico , Síndrome
17.
Rev Enferm ; 32(10): 16-9, 2009 Oct.
Artigo em Espanhol | MEDLINE | ID: mdl-20014621

RESUMO

Bach Flower Therapy is a method to cure and prevent physical and/or emotional disorders by means of treating our emotional unbalances. Primary Health Care Centers are an excellent site to apply this therapy since their main working instrument is an interview focused on patients. Over a 14 month period, a group of patients received this type of treatment in a Primary Health Care Center in Catalonia from a nurse at the center prepared to apply this therapy. The objective of this study is to describe the patients who received it, the identified nursing diagnoses, and the evolution of the physical and/or emotional disorders after treatment has been applied. Patients were enrolled in this therapy Project based on a request by the medical/nursing consultants treating patients or by a patient's own request to participate. 119 persons, of whom 78.15% were female, received personalized therapy until their health condition improved; seven patients had been excluded from this therapy since they only received a rescue remedy. The time period between the first and the last visit varied according to each case and the individual's personality 405 visits took place, an average of 3.4 per patient. Improvement was measured on the EVA scale: 87.4% of those patients who received treatment reported good or very good evolution/results. Bach Therapy appears to be a good alternative to psycho-pharmaceuticals, shows itself to be very effective, with fewer secondary effects, and less than 2% of patients evidencing gastric intolerance to this preparation.


Assuntos
Emoções , Flores , Terapias Mente-Corpo , Fitoterapia , Ansiedade/tratamento farmacológico , Depressão/tratamento farmacológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Estresse Psicológico/tratamento farmacológico
18.
Rev. Rol enferm ; 32(10): 656-659, oct. 2009.
Artigo em Espanhol | IBECS | ID: ibc-76189

RESUMO

La terapia floral del Dr. Bach es un método para curar y prevenir malestares físicos y/o emocionales a través de tratar los desequilibrios de nuestras emociones. Los centros de Atención Primaria constituyen un excelente lugar para aplicarla, puesto que su principal instrumento de trabajo es la entrevista centrada en el paciente. Durante 14 meses, un grupo de pacientes fue tratado por este método en un centro de Atención Primaria en Cataluña por una enfermera del centro formada para ello. El objetivo de este estudio es describir la población que recibió tratamiento, los diagnósticos de enfermería identificados y la evolución del malestar físico y/o emocional después del tratamiento. Los pacientes eran captados según demanda desde las consultas médica o de enfermería o bien por iniciativa propia. Recibieron terapia personalizada hasta mejorar su condición de salud 119 personas (78,15% mujeres) ; se habían excluido siete pacientes que sólo recibieron remedio de rescate. El período de tiempo entre la primera y última visita variaba según el caso y personalidad del individuo. Se efectuaron 405 visitas (una media de 3,4 por paciente). Se evaluó la mejora mediante la escala EVA: 87,4% de los pacientes tratados refirió evolución/resolución buena o muy buena. La terapia de Bach se presenta como una buena alternativa a los psicofármacos, muy efectiva, con menos efectos secundarios y menos de 2% de casos de intolerancia gástrica al preparado(AU)


Bach Flower Therapy is a method to cure and prevent physical and/or emotional disorders by means of treating our emotional unbalances. Primary Health Care Centers are an excellent site to apply this therapy, since their main working instrument is an interview focused on patients. Over a 14 month period, a group of patients received this type of treatment in a Primary Health Care Center in Catalonia from a nurse at the center prepared to apply this therapy. The objective of this study is to describe the patients who received it, the identified nursing diagnoses, and the evolution of the physical and/or emotional disorders after treatment has been applied. Patients were enrolled in this therapy Project based on a request by the medical/nursing consultants treating patients or by a patient’s own request to participate. 119 persons, of whom 78.15% were female, received personalized therapy until their health condition improved; seven patients had been excluded from this therapy since they only received a rescue remedy. The time period between the first and the last visit varied according to each case and the individual’s personality. 405 visits took place, an average of 3.4 per patient. Improvement was measured on the EVA scale: 87.4% of those patients who received treatment reported good or very good evolution/results. Bach Therapy appears to be a good alternative to psycho-pharmaceuticals, shows itself to be very effective, with fewer secondary effects, and less than 2% of patients evidencing gastric intolerance to this preparation(AU)


Assuntos
Humanos , Masculino , Feminino , Essências Florais , Psicoterapia/métodos , Psicoterapia/tendências , Transtornos Psicóticos Afetivos/terapia , Depressão/terapia , Solidão , Atenção Primária à Saúde/métodos , Atenção Primária à Saúde/tendências , Apoio Social , Sistemas de Apoio a Decisões Clínicas/tendências , Sistemas de Apoio a Decisões Clínicas , Estudos Retrospectivos , Ansiedade/terapia , Transtornos de Ansiedade/terapia
19.
Int J Pharm ; 333(1-2): 162-6, 2007 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-17074455

RESUMO

Hydrophilic matrices are a potentially useful option for the development of oral controlled-release formulations. The porous surface of these particles makes it possible to control or modify release of the active principle after administration. As a result, such formulations can be used in liquid controlled-release pharmaceutical formulations. We investigated a method of spontaneous drug encapsulation to prepare ethylcellulose polymer microparticles (since the polymer is synthetic rather than natural the final suspension is called pseudolatex) filled with morphine hydrochloride. Morphine is incorporated to water during the synthesis process and thus it is microencapsulated inside the micelles that give rise to the final microparticles. X-ray photoelectron spectroscopy (XPS), a technique that can identify elements in a sample without destroying it, was used for the chemical analysis of the surface of these microspheres. The results demonstrated the complete absence of morphine from the microsphere surface, which was taken as evidence that the drug had been completely encapsulated.


Assuntos
Analgésicos Opioides/química , Celulose/análogos & derivados , Portadores de Fármacos , Microesferas , Morfina/química , Celulose/química , Química Farmacêutica , Preparações de Ação Retardada , Composição de Medicamentos , Micelas , Nanotecnologia , Sensibilidade e Especificidade , Análise Espectral/métodos , Propriedades de Superfície , Tecnologia Farmacêutica , Raios X
20.
Int J Pharm ; 242(1-2): 291-4, 2002 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-12176266

RESUMO

Since hydrophilic matrices were proposed for controlled drug delivery, many polymeric excipients have been studied in order to make drug release fit the desired profiles. It has been pointed out that lambda-carrageenan, a sulphated polymer from algae, can suitably control the release rate of basic drugs from hydrophilic matrices with no need for complex technological processes. In this work, we propose a method to monitor morphologically the interaction between lambda-carrageenan and dexchlorpheniramine maleate (D-CPM), in order to find out how the release profiles can be so easily controlled. To this end, solutions of both polymer and drug were prepared at very low concentration. Solutions were mixed and samples were taken every hour over a period of 20 h. The characterization technique employed, atomic force microscopy (AFM), provides a high resolution, allowing to show the three-dimensional morphology of the samples within the nanometric scale. The results demonstrate that lambda-carrageenan is able to nanoencapsulate spontaneously D-CPM molecules, which offers the possibility to easily control the release rate of the drug. This work has moreover demonstrated the suitability of AFM for the specific case of the on-time monitoring of interaction processes that happen in pharmaceutical systems.


Assuntos
Composição de Medicamentos/métodos , Microscopia de Força Atômica/métodos , Nanotecnologia/métodos , Carragenina , Clorfeniramina/química , Excipientes , Antagonistas dos Receptores Histamínicos H1/química , Processamento de Imagem Assistida por Computador , Sonicação , Propriedades de Superfície
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