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2.
Ann R Coll Surg Engl ; 102(8): e198-e201, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32538111

RESUMO

Colorectal cancer metastasis to the retroperitoneum, especially solitary metastasis allowing curative resection, is rare. We report a case of complete resection of retroperitoneal metachronous solitary metastasis from caecal cancer without distant metastasis. An 80-year-old woman with caecal cancer underwent laparoscopic ileocaecal resection with regional lymph node dissection. According to the eighth edition of the TNM classification, the pathological diagnosis was stage IIA (T3N0M0). Six months following the surgery, computed tomography revealed a solitary mass of 2cm diameter, dorsal to the right kidney. A second procedure for the removal of the tumour was performed. The lesion was pathologically diagnosed as a metachronous solitary retroperitoneal metastasis from caecal cancer. The patient is surviving and free from recurrence 17 months following the second procedure.


Assuntos
Neoplasias do Ceco/patologia , Ceco , Íleo , Neoplasias Retroperitoneais , Idoso de 80 Anos ou mais , Ceco/diagnóstico por imagem , Ceco/patologia , Ceco/cirurgia , Feminino , Humanos , Íleo/diagnóstico por imagem , Íleo/patologia , Íleo/cirurgia , Laparoscopia , Neoplasias Retroperitoneais/diagnóstico , Neoplasias Retroperitoneais/patologia , Neoplasias Retroperitoneais/secundário , Neoplasias Retroperitoneais/cirurgia
3.
J Chem Phys ; 150(12): 124103, 2019 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-30927895

RESUMO

We have developed a combined quantum mechanics/molecular mechanics (QM/MM) method with periodic boundary condition (PBC) treatment of explicit electron-charge interactions in a theoretically rigorous manner, for an accurate description of electronic structures for molecules in the condensed phase. The Ewald summation technique is employed for the calculation of the one-electron Hamiltonian in an ab initio framework. We decompose the Coulomb interactions into two components: those within the same cell and those between different cells. The former is calculated in the same way as the conventional QM/MM calculation for isolated systems; this article focuses on our novel method for calculating the latter type of Coulomb interactions. The detailed formulation of the Hamiltonian of this new QM/MM-PBC method, as well as the necessary one-electron integrals and their gradients, is given. The novel method is assessed by applying it to the dilute water system and a system with a coumarin molecule in water solvent; it successfully reproduces the electronic energies, frontier orbital energies, and Mulliken population charge of the real-space limit calculated by QM/MM using large isolated systems. We investigated the contribution from each term of the Hamiltonian and found that the surface-dipole term in the Ewald summation technique is indispensable for QM/MM-PBC calculations. The newly developed QM/MM-PBC method is promising for tackling chemical reactions and excited states of molecules in the condensed phase.

4.
Sci Rep ; 7(1): 15478, 2017 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-29133830

RESUMO

Electron- or X-ray-induced characteristic X-ray analysis has been widely used to determine chemical compositions of materials in vast research fields. In recent years, analysis of characteristic X-rays from muonic atoms, in which a muon is captured, has attracted attention because both a muon beam and a muon-induced characteristic X-ray have high transmission abilities. Here we report the first non-destructive elemental analysis of a carbonaceous chondrite using one of the world-leading intense direct current muon beam source (MuSIC; MUon Science Innovative Channel). We successfully detected characteristic muonic X-rays of Mg, Si, Fe, O, S and C from Jbilet Winselwan CM chondrite, of which carbon content is about 2 wt%, and the obtained elemental abundance pattern was consistent with that of CM chondrites. Because of its high sensitivity to carbon, non-destructive elemental analysis with a muon beam can be a novel powerful tool to characterize future retuned samples from carbonaceous asteroids.

5.
Br J Surg ; 104(4): 377-383, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28072447

RESUMO

BACKGROUND: Total gastrectomy for gastric cancer is associated with excessive weight loss and decreased calorie intake. Nutritional support using eicosapentaenoic acid modulates immune function and limits catabolism in patients with advanced cancer, but its impact in the perioperative period is unclear. METHODS: This was a randomized phase III clinical trial of addition of eicosapentaenoic acid-rich nutrition to a standard diet in patients having total gastrectomy for gastric cancer. Patients were randomized to either a standard diet or standard diet with oral supplementation of an eicosapentaenoic acid (ProSure®), comprising 600 kcal with 2·2 g eicosapentaenoic acid, for 7 days before and 21 days after surgery. The primary endpoint was percentage bodyweight loss at 1 and 3 months after surgery. RESULTS: Of 127 eligible patients, 126 were randomized; 124 patients (61 standard diet, 63 supplemented diet) were analysed for safety and 123 (60 standard diet, 63 supplemented diet) for efficacy. Across both groups, all but three patients underwent total gastrectomy with Roux-en-Y reconstruction. Background factors were well balanced between the groups. Median compliance with the supplement in the immunonutrition group was 100 per cent before and 54 per cent after surgery. The surgical morbidity rate was 13 per cent in patients who received a standard diet and 14 per cent among those with a supplemented diet. Median bodyweight loss at 1 month after gastrectomy was 8·7 per cent without dietary supplementation and 8·5 per cent with eicosapentaenoic acid enrichment (P = 0·818, adjusted P = 1·000). Similarly, there was no difference between groups in percentage bodyweight loss at 3 months (P = 0·529, adjusted P = 1·000). CONCLUSION: Immunonutrition based on an eicosapentaenoic acid-enriched oral diet did not reduce bodyweight loss after total gastrectomy for gastric cancer compared with a standard diet. Registration number: UMIN000006380 ( http://www.umin.ac.jp/).


Assuntos
Ácido Eicosapentaenoico/administração & dosagem , Gastrectomia/métodos , Neoplasias Gástricas/cirurgia , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Peso Corporal , Suplementos Nutricionais , Feminino , Humanos , Fatores Imunológicos/administração & dosagem , Laparoscopia/métodos , Masculino , Pessoa de Meia-Idade , Apoio Nutricional/métodos , Assistência Perioperatória/métodos , Neoplasias Gástricas/dietoterapia , Adulto Jovem
8.
AJNR Am J Neuroradiol ; 36(7): 1343-8, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25836725

RESUMO

BACKGROUND AND PURPOSE: Human papillomavirus-associated oropharyngeal squamous cell carcinoma is increasing in prevalence and typically occurs in younger patients than human papillomavirus-negative squamous cell carcinoma. While imaging features of human papillomavirus-positive versus human papillomavirus-negative squamous cell carcinoma nodal metastases have been described, characteristics distinguishing human papillomavirus-positive from human papillomavirus-negative primary squamous cell carcinomas have not been well established. The purpose of this project was to evaluate the use of texture features to distinguish human papillomavirus-positive and human papillomavirus-negative primary oropharyngeal squamous cell carcinoma. MATERIALS AND METHODS: Following institutional review board approval, 40 patients with primary oropharyngeal squamous cell carcinoma and known human papillomavirus status who underwent contrast-enhanced CT between December 2009 and October 2013 were included in this study. Segmentation of the primary lesion was manually performed with a semiautomated graphical-user interface. Following segmentation, an in-house-developed texture analysis program extracted 42 texture features from each segmented volume. A t test was used to evaluate differences in texture parameters between human papillomavirus-positive and human papillomavirus-negative squamous cell carcinomas. RESULTS: Of the 40 included patients, 29 had human papillomavirus-positive oropharyngeal squamous cell carcinoma and 11 had human papillomavirus-negative oropharyngeal squamous cell carcinoma. Significant differences were seen in the histogram parameters median (P = .006) and entropy (P = .016) and squamous cell carcinoma entropy (P = .043). CONCLUSIONS: There are statistically significant differences in some texture features between human papillomavirus-positive and human papillomavirus-negative oropharyngeal tumors. Texture analysis may be considered an adjunct to the evaluation of human papillomavirus status and characterization of squamous cell carcinoma.


Assuntos
Carcinoma de Células Escamosas/virologia , Interpretação de Imagem Assistida por Computador/métodos , Neoplasias Orofaríngeas/virologia , Infecções por Papillomavirus/diagnóstico , Tomografia Computadorizada por Raios X/métodos , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Orofaríngeas/diagnóstico por imagem , Neoplasias Orofaríngeas/patologia , Infecções por Papillomavirus/epidemiologia
9.
Osteoarthritis Cartilage ; 22(9): 1301-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25008209

RESUMO

OBJECTIVE: We evaluated the effect of a reduction in the systemic ratio of n-6:n-3 polyunsaturated fatty acids (PUFAs) on changes in inflammation, glucose metabolism, and the idiopathic development of knee osteoarthritis (OA) in mice. We hypothesized that a lower ratio of n-6:n-3 PUFAs would protect against OA markers in cartilage and synovium, but not bone. DESIGN: Male and female fat-1 transgenic mice (Fat-1), which convert dietary n-6 to n-3 PUFAs endogenously, and their wild-type (WT) littermates were fed an n-6 PUFA enriched diet for 9-14 months. The effect of gender and genotype on serum PUFAs, interleukin (IL)-6, tumor necrosis factor (TNF)-α, and glucose tolerance was tested by 2-factor analysis of variance (ANOVA). Cortical and trabecular subchondral bone changes were documented by micro-focal computed tomography (CT), and knee OA was assessed by semi-quantitative histomorphometry grading. RESULTS: The n-6:n-3 ratio was reduced 12-fold and 7-fold in male and female Fat-1 mice, respectively, compared to WT littermates. IL-6 and TNF-α levels were reduced modestly in Fat-1 mice. However, these systemic changes did not reduce osteophyte development, synovial hyperplasia, or cartilage degeneration. Also the fat-1 transgene did not alter subchondral cortical or trabecular bone morphology or bone mineral density. CONCLUSIONS: Reducing the systemic n-6:n-3 ratio does not slow idiopathic changes in cartilage, synovium, or bone associated with early-stage knee OA in mice. The anti-inflammatory and anti-catabolic effects of n-3 PUFAs previously reported for cartilage may be more evident at later stages of disease or in post-traumatic and other inflammatory models of OA.


Assuntos
Artrite Experimental/prevenção & controle , Gorduras Insaturadas na Dieta/uso terapêutico , Ácidos Graxos Ômega-3/sangue , Ácidos Graxos Ômega-6/sangue , Osteoartrite/prevenção & controle , Animais , Artrite Experimental/metabolismo , Artrite Experimental/patologia , Biomarcadores/metabolismo , Glicemia/metabolismo , Peso Corporal , Cartilagem Articular/patologia , Citocinas/sangue , Ácidos Graxos Ômega-6/administração & dosagem , Ácidos Graxos Ômega-6/uso terapêutico , Feminino , Masculino , Camundongos Transgênicos , Osteoartrite/metabolismo , Osteoartrite/patologia , Membrana Sinovial/patologia , Tíbia/patologia
10.
J Periodontal Res ; 48(5): 591-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23317284

RESUMO

BACKGROUND: Antimicrobial photodynamic therapy (aPDT) is a new treatment method for the removal of infectious pathogens using a photosensitizer and light of a specific wavelength, e.g., toluidine blue with a wavelength of about 600 nm. We explored a new photosensitizer and focused on indocyanine green (ICG), which has high absorption at a wavelength of 800-805 nm. We investigated the bactericidal effect of PDT on Porphyromonas gingivalis using a new photosensitizer, ICG-loaded nanospheres with an 805 nm wavelength low-level diode laser irradiation. METHODS: We designed ICG-loaded nanospheres coated with chitosan (ICG-Nano/c) as a photosensitizer. A solution containing Porphyromonas gingivalis (10(8)  CFU/mL) with or without ICG-Nano/c (or ICG) was prepared and irradiated with a diode laser or without laser irradiation as a negative control. The irradiation settings were 0.5 W with a duty ratio of 10%, for 3-100 ms in repeated pulse (RPT) or continuous wave mode. CFU were counted after 7 d of anaerobic culture. RESULTS: We observed that ICG-Nano/c could adhere to the surface of P. gingivalis. When ICG-Nano/c was used for aPDT, irradiation with RPT 100 ms mode gave the lowest increase in temperature. Laser irradiation with ICG-Nano/c significantly reduced the number of P. gingivalis (i.e., approximately 2-log10 bacterial killing). The greatest bactericidal effect was found in the RPT 100 ms group. However, laser irradiation (RPT 100 ms) with ICG, as well as without photosensitizer, had no effect on the number of bacteria. CONCLUSIONS: Within the limits of this study, ICG-Nano/c with low-level diode laser (0.5 W; 805 nm) irradiation showed an aPDT-like effect, which might be useful for a potential photodynamic periodontal therapy.


Assuntos
Antibacterianos/administração & dosagem , Sistemas de Liberação de Medicamentos , Verde de Indocianina/administração & dosagem , Lasers Semicondutores/uso terapêutico , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/administração & dosagem , Porphyromonas gingivalis/efeitos dos fármacos , Aderência Bacteriana , Carga Bacteriana/efeitos dos fármacos , Quitosana/química , Humanos , Viabilidade Microbiana/efeitos dos fármacos , Microscopia Eletrônica de Varredura , Microscopia de Fluorescência , Microscopia de Contraste de Fase , Nanosferas/química , Doenças Periodontais/microbiologia , Doses de Radiação , Temperatura
11.
Int J Sports Med ; 32(7): 559-64, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21567354

RESUMO

Erythropoietin promotes the production of red blood cells. Recombinant human erythropoietin is illicitly used to improve performance in endurance sports. Expression of the ERYTHROPOIETIN gene is negatively controlled by the transcription factor GATA-binding protein (GATA). Specific GATA inhibitors have recently been developed as novel drugs for the management of anemia. These drugs could, therefore, be illicitly used like recombinant human erythropoietin to improve performance in sports. To examine alterations in levels of plasma protein after administration of GATA inhibitors, proteomic analyses were conducted on mouse plasma samples treated with the potent GATA inhibitor K-11706. The analysis based on gel electrophoresis identified 41 protein spots differentially expressed when compared with normal plasma. Each spot was identified with liquid chromatography coupled to tandem mass spectrometry and 2 of them, fetuin-B and prothrombin, were verified by Western blotting. The results showed that the expression of fetuin-B in mice plasma was increased by K-11706, but not by recombinant human erythropoietin or hypoxia. These results suggest the potential of proteomic-based approaches as tools to identify biomarkers for the illegal use of novel drugs (e.g., GATA inhibitors). Also, fetuin-B could be a sensitive marker for the detection of abuse of GATA inhibitors.


Assuntos
Fatores de Transcrição GATA/antagonistas & inibidores , Proteômica/métodos , Animais , Biomarcadores/sangue , Western Blotting , Cromatografia Líquida , Dopagem Esportivo , Eletroforese em Gel de Poliacrilamida , Eritropoetina/farmacologia , Fetuína-B , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Camundongos , Camundongos Endogâmicos ICR , Protrombina/efeitos dos fármacos , Protrombina/genética , Protrombina/metabolismo , Proteínas Recombinantes , Detecção do Abuso de Substâncias/métodos , Espectrometria de Massas em Tandem , alfa-Fetoproteínas/efeitos dos fármacos , alfa-Fetoproteínas/genética , alfa-Fetoproteínas/metabolismo
12.
Mol Oral Microbiol ; 25(3): 200-6, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20536747

RESUMO

Aggregatibacter actinomycetemcomitans is usually isolated from the oral cavity where it is associated with active periodontitis. The species can be divided into six serotypes (a-f) according to their surface carbohydrate antigens. However, some clinical isolates cannot be grouped within these six serotypes. Gram-negative, facultative anaerobic, catalase-positive coccobacilli were isolated from a patient with periodontitis and identified by employing genetic, biochemical and serological analyses. Phenotypic data identified the isolate as A. actinomycetemcomitans. Serotype-specific polysaccharide antigen from the isolate was untypeable by immunodiffusion testing in comparison with reference A. actinomycetemcomitans serotype a to f strains. Biofilm formation by the isolate was strong but cytotoxic activity was low. Gas chromatography/mass spectroscopy analysis of partially methylated alditol acetates from surface polysaccharide showed the presence of 2,4-di-O-methyl-rhamnose and 2,3,6-tri-O-methyl-glucose, with a 1 : 1 m ratio. The (1)H- and (13)C-nuclear magnetic resonance spectra of the antigen showed that both constituent glycoses had alpha-anomeric configuration. It is proposed that the untyped strain is a new A. actinomycetemcomitans serotype, designated serotype g.


Assuntos
Aggregatibacter actinomycetemcomitans/classificação , Periodontite Crônica/microbiologia , Polissacarídeos Bacterianos/química , Biofilmes , Sobrevivência Celular , Cromatografia Gasosa , DNA Bacteriano/análise , Células HL-60/microbiologia , Humanos , Espectrometria de Massas , Bolsa Periodontal/microbiologia , Reação em Cadeia da Polimerase , Sorotipagem/métodos , Álcoois Açúcares/análise
13.
Br J Surg ; 96(9): 1015-22, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19644974

RESUMO

BACKGROUND: Locally advanced gastric cancer with extensive lymph node metastasis is usually considered unresectable and so treated by chemotherapy. This trial explored the safety and efficacy of preoperative chemotherapy followed by extended surgery in the management of locally advanced gastric adenocarcinoma. METHODS: Patients with gastric cancer with extensive lymph node metastasis received two or three 28-day cycles of induction chemotherapy with irinotecan (70 mg/m(2) on days 1 and 15) and cisplatin (80 mg/m(2) on day 1), and then underwent gastrectomy with curative intent with D2 plus para-aortic lymphadenectomy. Primary endpoints were 3-year overall survival and incidence of treatment-related death. RESULTS: The study was terminated because of three treatment-related deaths when 55 patients had been enrolled (mortality rate above 5 per cent). Two deaths were due to myelosuppression and one to postoperative complications. Clinical response and R0 resection rates were 55 and 65 per cent respectively. The pathological response rate was 15 per cent. Median overall survival was 14.6 months and the 3-year survival rate 27 per cent. CONCLUSION: This multimodal treatment of locally advanced gastric cancer provides reasonable 3-year survival compared with historical data, but at a considerable cost in terms of morbidity and mortality.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/cirurgia , Idoso , Camptotecina/administração & dosagem , Camptotecina/efeitos adversos , Camptotecina/análogos & derivados , Quimioterapia Adjuvante , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Métodos Epidemiológicos , Feminino , Gastrectomia/mortalidade , Humanos , Irinotecano , Excisão de Linfonodo , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Neoplasias Gástricas/mortalidade , Resultado do Tratamento
14.
Diabetologia ; 52(7): 1434-41, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19436992

RESUMO

AIMS/HYPOTHESIS: Although it is known that lipid metabolism plays a role in insulin resistance in type 2 diabetes and in obesity, the mechanism is still largely unknown. Apolipoprotein E (ApoE) regulates plasma lipid levels and also plays a role in the uptake of lipids into various tissues. To investigate whether the suppression of whole-particle lipoprotein uptake into tissues affects insulin responsiveness and the diabetic condition, we examined the effect of an ApoE (also known as Apoe) gene deletion in MKR mice, a mouse model of type 2 diabetes. METHODS: ApoE ( -/- ), MKR, ApoE ( -/- )/MKR and control mice were placed on a high-fat, high-cholesterol diet for 16 weeks. Glucose tolerance, serum insulin, blood glucose, insulin tolerance, tissue triacylglycerol content and atherosclerotic lesions were assessed. RESULTS: ApoE ( -/- )/MKR and ApoE ( -/- ) mice showed significantly improved blood glucose, glucose tolerance and insulin sensitivity. Reduced triacylglycerol content in liver and reduced fat accumulation in liver and adipose tissue were found in ApoE ( -/- )/MKR and ApoE ( -/- ) mice compared with control and MKR mice. ApoE ( -/- ) and ApoE ( -/- )/MKR mice demonstrated similarly large atherosclerotic lesions, whereas MKR and control mice had small atherosclerotic lesions. CONCLUSIONS/INTERPRETATION: We demonstrated that ApoE deficiency abrogates insulin resistance in a mouse model of type 2 diabetes, suggesting that lipid accumulation in tissue is a major cause of insulin resistance in this mouse model.


Assuntos
Apolipoproteínas E/genética , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/fisiopatologia , Resistência à Insulina/fisiologia , Metabolismo dos Lipídeos/fisiologia , Tecido Adiposo/metabolismo , Animais , Apolipoproteínas E/deficiência , Aterosclerose/metabolismo , Aterosclerose/fisiopatologia , Glicemia/metabolismo , Composição Corporal/fisiologia , Peso Corporal/fisiologia , Colesterol na Dieta/sangue , Colesterol na Dieta/farmacologia , Angiopatias Diabéticas/metabolismo , Angiopatias Diabéticas/fisiopatologia , Modelos Animais de Doenças , Ácidos Graxos não Esterificados/sangue , Feminino , Insulina/sangue , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos , Camundongos Mutantes , Triglicerídeos/sangue
15.
Pharmazie ; 63(10): 721-5, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18972833

RESUMO

Insulin-lauryl sulfate (INS-SDS) complex loaded poly (lactic acid-co-glycolic acid) (PLGA) nanoparticles were prepared by spontaneous emulsion solvent diffusion method. To improve the insulin entrapment efficiency (E.E), a five-level-two-factor central composite design and surface response methodology (RSM) was used to determine the optimum levels of PLGA/INS complex weight ratio and PVA/ acetone volume ratio, two important variables during nanoparticles fabrication. A quadratic model to express the E.E as a function of the two studied factors was developed. Only 10 experimental runs were necessary and the obtained model was adequate (P < 0.05). By partial derivative resolution of regression model, the optimum weight ratio of PLGA/INS complex and volume ratio of PVA/acetone was determined as 25/1 and 10/1, respectively. This preparing condition resulted E.E of insulin as high as 91% during nanoparticles production. Validation of the model was accomplished by experiments carried out on optimized formulation conditions. The experimental results were in good agreement with those predicted by the model. The results indicated that RSM represents an effective and potential technique for formulation optimization.


Assuntos
Hipoglicemiantes/administração & dosagem , Insulina/administração & dosagem , Dodecilsulfato de Sódio/química , Sistemas de Liberação de Medicamentos , Emulsões , Excipientes , Hipoglicemiantes/química , Insulina/química , Ácido Láctico , Modelos Estatísticos , Nanopartículas , Tamanho da Partícula , Ácido Poliglicólico , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Análise de Regressão , Tensoativos
16.
Pharmazie ; 63(12): 866-71, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19177901

RESUMO

Insulin, a water soluble peptide hormone, was hydrophobically ion-paired with sodium lauryl sulfate (SDS) at the stoichiometric molar ratio of 6:1. The obtained insulin-SDS complex precipitation was subsequently formulated in biodegradable poly (D,L-lactic-co-glycolic acid) (PLGA) nanoparticles by a modified spontaneous emulsion solvent diffusion method. Compared with a conventional method for free insulin encapsulation, direct dissolution of SDS-paired insulin in the non-aqueous organic phase led to an increase in drug recovery from 42.5% to 89.6%. The more hydrophobic complex contributes to the improved affinity of insulin to the polymer matrix, resulting in a higher drug content in the nanoparticles. The drug loading was investigated by determining initial burst release at the first 30 min. The results showed that 64.8% of recovered drug were preferentially surface bound on complex loaded nanoparticles. The in vitro drug release was characterized by an initial burst and subsequent delayed release in dissolution media of deionized water and phosphate buffer saline (PBS). Compared with that in PBS, nanoparticles in deionized water medium presented very low initial burst release (15% vs. 65%) and incomplete cumulative release (25% vs. 90%) of the drug. In addition, dialysis experiments were performed to clarify the form of the released insulin in the dissolution media. The results suggested that the ion-pair complex was sensitive to ionic strength, insulin was released from the particular matrix as complex form and subsequently suffered dissociation from SDS in buffer saline. Moreover, the in vivo bioactivity of the SDS-paired insulin and nanoparticulate formulations were evaluated in mice by estimation of their blood sugar levels. The results showed that the bioactivity of insulin was unaltered after the ion-pairing process.


Assuntos
Hipoglicemiantes/administração & dosagem , Insulina/administração & dosagem , Dodecilsulfato de Sódio/administração & dosagem , Animais , Glicemia/metabolismo , Química Farmacêutica , Diálise , Composição de Medicamentos , Excipientes , Liofilização , Hipoglicemiantes/análise , Hipoglicemiantes/farmacologia , Insulina/análise , Insulina/farmacologia , Ácido Láctico , Camundongos , Nanopartículas , Tamanho da Partícula , Ácido Poliglicólico , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Dodecilsulfato de Sódio/análise , Solubilidade
17.
Clin Nephrol ; 67(1): 12-9, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17269594

RESUMO

BACKGROUND: Maxacalcitol is a vitamin D analogue, which is administered intravenously for secondary hyperparathyroidism in dialysis patients as well as calcitriol. However, few dose-comparison clinical studies have been reported for these drugs. The present multicenter, randomized crossover study was conducted to determine the equivalence of maxacalcitol and calcitriol doses. METHODS: Subjects comprised 31 patients on chronic hemodialysis with secondary hyperparathyroidism who had not received maxacalcitol or calcitriol in the previous 3 months. Patients were randomly divided into two groups, and maxacalcitol or calcitriol was administered in a crossover design for 12 weeks each. Maxacalcitol and calcitriol doses were adjusted based on serum levels of calcium and intact parathyroid hormone. RESULTS: After the 12-week maxacalcitol/calcitriol administration, there were no significant differences in levels of calcium (maxacalcitol 2.40+/-0.22 mmol/1 (9.6+/-0.9 mg/dl), calcitriol 2.42 + 0.25 mmol/l (9.7+/-1.0 mg/dl), p = 0.71), phosphate (maxacalcitol 1.97 + 0.42 mmol/l (6.1+/-1.3 mg/dl), calcitriol 2.00+/-0.48 mmol/l (6.2+/-1.5 mg/dl), p = 0.64), intact parathyroid hormone (maxacalcitol 267+/-169 pg/ml, calcitriol 343+/-195 pg/ml, p = 0.11) in serum or other bone-metabolic parameters such as serum alkaline phosphatase. The doses ofmaxacalcitol and calcitriol were 49.3+/-23.7 microg/month and 9.0+/-3.8 microg/month, respectively, and maxacalcitol : calcitriol dose ratio was 5.5: 1. No severe adverse reactions were seen for either maxacalcitol or calcitriol during the study period. CONCLUSIONS: Comparable therapeutic efficacy can be obtained in the treatment of secondary hyperparathyroidism using either maxacalcitol or calcitriol at a dose ratio of 5.5 : 1.


Assuntos
Calcitriol/análogos & derivados , Calcitriol/uso terapêutico , Hiperparatireoidismo Secundário/tratamento farmacológico , Diálise Renal , Vitamina D/análogos & derivados , Idoso , Cálcio/sangue , Estudos Cross-Over , Relação Dose-Resposta a Droga , Feminino , Humanos , Hiperparatireoidismo Secundário/sangue , Hiperparatireoidismo Secundário/etiologia , Masculino , Pessoa de Meia-Idade , Hormônio Paratireóideo/sangue
18.
Int J Pharm ; 331(2): 176-81, 2007 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-17126507

RESUMO

Salmon calcitonin (sCT) powders suitable for inhalation, containing chitosan and mannitol as absorption enhancer and protection agent, respectively, were prepared using a spray-drying process. The effect of chitosan on physicochemical stability of sCT in the dry powder was investigated by different analytical techniques. High-performance liquid chromatography (HPLC) analysis indicated that sCT was chemically stable upon spray-drying. With the proportion of chitosan in spray-drying formulation being increased, dissolution of sCT from the dry powders was decreased both in phosphate buffer and acetate buffer. The thioflavine T fluorescence assay showed that no fibrils were present in the spray-dried powder. However, sCT partly fibrillated in the phosphate buffer, but not in acetate buffer. Fourier transform infrared (FTIR) spectra showed that the secondary structure of sCT was slightly changed in the dry powder, yet no aggregate signal was observed. Circular dichroism analysis indicated that the structure of sCT in an aqueous formulation was slightly altered by addition of chitosan. Nevertheless, recovery of sCT was not influenced by chitosan in the aqueous formulation as indicated by HPLC analysis. This study suggested that sCT, in absence of any additives, was stable during the spray-drying process under certain conditions. Addition of chitosan affects recovery of sCT from spray-dried powders, which may be due to formation of a partially irreversible complex between the protein and chitosan during the spray-drying process.


Assuntos
Calcitonina/administração & dosagem , Pós/administração & dosagem , Administração por Inalação , Animais , Soluções Tampão , Calcitonina/química , Quitosana , Cromatografia Líquida de Alta Pressão , Estabilidade de Medicamentos , Excipientes , Manitol , Conformação Proteica , Salmão , Análise Espectral
19.
Neuropediatrics ; 37(3): 115-20, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16967360

RESUMO

We report on the complication of gastroesophageal reflux (GER) in four patients with lower brainstem dysfunction. These patients suffered from perinatal asphyxia, cerebellar hemorrhage, or congenital dysphagia of unknown origin and showed facial nerve palsy, inspiratory stridor due to vocal cord paralysis, central sleep apnea, and dysphagia, in various combinations. Naso-intestinal tube feeding was introduced in all of the patients due to recurrent vomiting and aspiration pneumonia resulting from GER. T2-weighted magnetic resonance (MR) imaging revealed symmetrical high intensity lesions in the tegmentum of the lower pons and the medulla oblongata in two of the patients, and pontomedullary atrophy in another patient. In normal subjects, lower esophageal sphincter contraction is provoked by distension of the gastric wall, through a vago-vagal reflex. Since this reflex arc involves the solitary tract nucleus, where the swallowing center is located, the association of dysphagia and GER in the present patients is thought to result from the lesions in the tegmentum of medulla oblongata. We propose the term "dysphagia-GER complex" to describe the disturbed motility of the upper digestive tract due to lower brainstem involvement. In children with brainstem lesions, neurological assessment of GER is warranted, in addition to the examination of other signs of brainstem dysfunction, including dysphagia and respiratory disturbance.


Assuntos
Refluxo Gastroesofágico/patologia , Refluxo Gastroesofágico/fisiopatologia , Reflexo/fisiologia , Núcleo Solitário/anormalidades , Nervo Vago/fisiopatologia , Pré-Escolar , Feminino , Humanos , Lactente , Imageamento por Ressonância Magnética/métodos , Masculino , Modelos Biológicos , Tomografia Computadorizada por Raios X/métodos
20.
J Liposome Res ; 16(2): 127-41, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16753967

RESUMO

The objectives of this study were to observe the penetrative and mucoadhesive behavior of polymer-coated liposomes into the intestinal mucosa of rats. Chitosan (CS) and negatively charged liposomes were chosen as model polymer-coated liposomes. In order to observe their behavior, chitosan was labeled with Fluorescence Isothiocyanate (FITC) via chemical reaction at the isothiocyanate group of FITC and the primary amino group of chitosan; the liposomes (Lips) were marked by incorporation of DiI into the liposomal formulation. FITC-labeled chitosan (FITC-CS), Non-Lips, and FITC-labeled CS-coated Liposomes (FITC-CS-Lips) were intragastrically administered into male Wistar rats, and the behavior of the molecules was subsequently visualized by CLSM (Confocal Laser Scanning Microscopy). The results demonstrated that the chitosan molecules themselves, as well as the liposomes, could penetrate across the intestinal mucosa. Moreover, the CLSM images demonstrated a lack of separation of the chitosan molecules from the surface of the liposomes after the administration of chitosan-coated liposomes.


Assuntos
Quitosana/química , Portadores de Fármacos/química , Lipossomos/química , Adesividade , Animais , Portadores de Fármacos/farmacocinética , Fluoresceína-5-Isotiocianato , Fluoresceínas , Mucosa Intestinal/metabolismo , Masculino , Ratos , Ratos Wistar , Propriedades de Superfície
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