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1.
Prehosp Emerg Care ; 22(6): 784-787, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29768077

RESUMO

OBJECTIVE: Most cardiac arrests occur in the private setting where response is often delayed and outcomes are poor. We surveyed public safety personnel to determine if they would volunteer to respond into private locations and/or be equipped with a personal automated external defibrillator (AED) as part of a vetted responder program that would use smart geospatial technology. METHODS: We conducted an anonymized survey among personnel from fire-based emergency medical services (EMS) and search and rescue organizations from Washington State. The goal of the survey was to evaluate whether there was interest among cardiopulmonary resuscitation (CPR)-trained, public safety personnel to respond with or without an AED to private-residence cardiac arrest outside of working hours using a smartphone platform. We used a 5-point Likert scale to assess responses. RESULTS: Overall the response rate was 73.7% (527/715). Two-thirds of respondents were between the ages of 30-59 with a similar proportion certified as a firefighter-emergency medical technician (EMT). Most were male (80%). As a vetted volunteer responder, the majority would "almost always" or "often" respond to private (79.7%) or public locations (85.2%) outside of work hours. The majority (54.1%) would store the AED in their vehicle while 38% would plan to keep the AED on their person. A total of 83% were "definitely' or "probably interested" in participating in the program. CONCLUSION: The results of this survey indicate that public safety personnel are willing to respond to suspected cardiac arrest during off-hours using geospatial smart technology to private locations with or without an AED.


Assuntos
Plantão Médico , Parada Cardíaca/terapia , Instalações Privadas , Segurança , Voluntários , Adulto , Reanimação Cardiopulmonar/educação , Desfibriladores , Serviços Médicos de Emergência/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Voluntários/educação , Washington
2.
Mol Pharm ; 14(11): 3718-3728, 2017 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-28922604

RESUMO

Fluid bed coating offers potential advantages as a formulation platform for amorphous solid dispersions (ASDs) of poorly soluble drugs, being a one-step manufacturing process which could reduce the risk of phase separation associated with multiple step manufacturing approaches. However, the impact of the physicochemical nature of nonpareil carriers on the properties and drug release from the ASDs has not been studied in detail. In this work, tartaric acid (TAP) and microcrystalline cellulose (CEL) spheres were chosen as examples of functional and inert beads, respectively. Two structurally related triazole antifungals, itraconazole (ITR) and posaconazole (POS), were chosen as model drugs. Solid-state investigations revealed that the fluidized bed process result in both types of spheres uniformly coated with ITR and POS ASDs based on Eudragit L100-55 (EUD). A single glass transition temperature (Tg) was determined for each of the ASDs. Infrared studies suggested the presence of a weak interaction between POS and TAP, which translated into premature release of POS from the POS/EUD ASD coated TAP spheres in FaSSGF and subsequently lower POS cumulative release in comparison to the ASD coated on CEL beads. High resolution investigations of morphological and compositional changes during dissolution, using scanning electron microscopy and atomic force microscopy coupled with nanoscale thermal investigation, revealed that crystallization of the drug from the ASDs was induced during dissolution when TAP spheres were used as carriers. In contrast, ASDs coated on CEL underwent phase separation and drug-rich nanospecies were formed in the matrix due to the solubility gap between the drug and EUD in FaSSIF. This study demonstrates that properties of carrier for the ASD fundamentally affect the drug release properties and the proper selection of carrier beads is critical to ensure product quality.


Assuntos
Antifúngicos/química , Itraconazol/química , Triazóis/química , Celulose/química , Tartaratos/química
3.
Mol Pharm ; 13(1): 100-12, 2016 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-26641021

RESUMO

Ciprofloxacin (CIP) is an antibiotic that has been clinically trialed for the treatment of lung infections by aerosolization. However, CIP is rapidly systemically absorbed after lung administration, increasing the risk for subtherapeutic pulmonary concentrations and resistant bacteria selection. In the presence of calcium, CIP forms complexes that reduce its oral absorption. Such complexation may slow down CIP absorption from the lung thereby maintaining high concentration in this tissue. Thus, we developed inhalable calcium-based inorganic-organic composite microparticles to sustain CIP within the lung. The aerodynamics and micromeritic properties of the microparticles were characterized. FTIR and XRD analysis suggest that the inorganic component of the particles comprised amorphous calcium carbonate and amorphous calcium formate, and that CIP and calcium interact in a 1:1 stoichiometry in the particles. CIP was completely released from the microparticles within 7 h, with profiles showing a slight dependence on pH (5 and 7.4) compared to the dissolution of pure CIP. Transport studies of CIP across Calu-3 cell monolayers, in the presence of various calcium concentrations, showed a decrease of up to 84% in CIP apparent permeability. The apparent minimum inhibitory concentration of CIP against Pseudomonas aeruginosa and Staphylococcus aureus was not changed in the presence of the same calcium concentration. These results indicate that the designed particles should provide sustained levels of CIP with therapeutic effect in the lung. With these microparticles, it should be possible to control CIP pharmacokinetics within the lung, based on controlled CIP release from the particles and reduced apparent permeability across the epithelial barrier due to the cation-CIP interaction.


Assuntos
Antibacterianos/farmacologia , Ciprofloxacina/farmacologia , Linhagem Celular , Humanos , Pulmão/microbiologia , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Pseudomonas aeruginosa/efeitos dos fármacos , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus/efeitos dos fármacos , Difração de Raios X
4.
Pharm Res ; 31(10): 2735-47, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24867420

RESUMO

PURPOSE: Some patients are unable to generate the peak inspiratory flow rate (PIFR) necessary to de-agglomerate drug particles from dry powder inhalers (DPIs). In this study we tested the hypothesis that the acoustic parameters of an inhalation are related to the PIFR and hence reflect drug delivery. METHODS: A sensitivity analysis of the relationship of the acoustics of inhalation to simultaneously recorded airflow, in a cohort of volunteers (n = 92) was performed. The Next Generation Impactor (NGI) was used to assess in vitro drug delivery from salmeterol/fluticasone and salbutamol Diskus™ DPIs. Fine particle fraction, FPF, (<5 µm) was measured at 30-90 l/min for 2-6 s and correlated with acoustically determined flow rate (IFRc). In pharmacokinetic studies using a salbutamol (200 µg) Diskus™, volunteers inhaled either at maximal or minimal effort on separate days. RESULTS: PIFRc was correlated with spirometrically determined values (R (2) = 0.88). In in vitro studies, FPF increased as both flow rate and inhalation duration increased for the salmeterol/fluticasone Diskus™ (Adjusted R (2) = 0.95) and was proportional to flow rate only for the salbutamol Diskus™ (Adjusted R (2) = 0.71). In pharmacokinetic studies, blood salbutamol levels measured at 20 min were significantly lower when PIFRc was less than 60 l/min, p < 0.0001. CONCLUSION: Acoustically-determined PIFR is a suitable method for estimating drug delivery and for monitoring inhalation technique over time.


Assuntos
Acústica/instrumentação , Sistemas de Liberação de Medicamentos/instrumentação , Inaladores de Pó Seco , Inalação/fisiologia , Capacidade Inspiratória/fisiologia , Administração por Inalação , Aerossóis , Albuterol/administração & dosagem , Albuterol/análogos & derivados , Albuterol/sangue , Albuterol/farmacocinética , Androstadienos/administração & dosagem , Androstadienos/sangue , Androstadienos/farmacocinética , Combinação de Medicamentos , Desenho de Equipamento , Combinação Fluticasona-Salmeterol , Humanos
5.
Pharmaceuticals (Basel) ; 17(4)2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38675376

RESUMO

The use of herbal medicine as an adjuvant therapy in the management of gastric cancer has yielded encouraging outcomes, notably in enhancing overall survival rates and extending periods of disease remission. Additionally, herbal medicines have demonstrated potential anti-metastatic effects in gastric cancer. Despite these promising findings, there remains a significant gap in our understanding regarding the precise pharmacological mechanisms, the identification of specific herbal compounds, and their safety and efficacy profiles in the context of gastric cancer therapy. In addressing this knowledge deficit, the present study proposes a comprehensive exploratory analysis of the Tiao-Yuan-Tong-Wei decoction (TYTW), utilizing an integrative approach combining system pharmacology and molecular docking techniques. This investigation aims to elucidate the pharmacological actions of TYTW in gastric pathologies. It is hypothesized that the therapeutic efficacy of TYTW in counteracting gastric diseases stems from its ability to modulate key signaling pathways, thereby influencing PIK3CA activity and exerting anti-inflammatory effects. This modulation is observed predominantly in pathways such as PI3K/AKT, MAPK, and those directly associated with gastric cancer. Furthermore, the study explores how TYTW's metabolites (agrimoniin, baicalin, corosolic acid, and luteolin) interact with molecular targets like AKT1, CASP3, ESR1, IL6, PIK3CA, and PTGS2, and their subsequent impact on these critical pathways and biological processes. Therefore, this study represents preliminary research on the anticancer molecular mechanism of TYTW by performing network pharmacology and providing theoretical evidence for further experimental investigations.

6.
Nat Genet ; 30(1): 102-5, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11743583

RESUMO

High-density lipoproteins (HDLs) are anti-atherogenic lipoproteins that have a major role in transporting cholesterol from peripheral tissues to the liver, where it is removed. Epidemiologic studies have shown that low levels of high-density lipoprotein-cholesterol (HDL-C) are associated with an increased incidence of coronary heart disease and an increased mortality rate, indicating a protective role of high concentrations of HDL-C against atherogenesis and the development of coronary heart disease. HDL-C level is influenced by several genetic and nongenetic factors. Nongenetic factors include smoking, which has been shown to decrease the HDL-C level. Exercise and alcohol have been shown to increase HDL-C levels. Decreased HDL-C is often associated with other coronary heart disease risk factors such as obesity, hyperinsulinemia and insulin resistance, hypertriglyceridemia and hypertension. Although several genes have been identified for rare forms of dyslipidemia, the genes accounting for major variation in HDL-C levels have yet to be identified. Using a multipoint variance components linkage approach, we found strong evidence of linkage (lod score=3.4; P=0.00004) of a quantitative trait locus (QTL) for HDL-C level to a genetic location between markers D9S925 and D9S741 on chromosome 9p in Mexican Americans. A replication study in an independent set of Mexican American families confirmed the existence of a QTL on chromosome 9p.


Assuntos
HDL-Colesterol/sangue , Cromossomos Humanos Par 9/genética , Hiperlipoproteinemia Tipo II/genética , Americanos Mexicanos/genética , Adulto , Idoso , Doenças Cardiovasculares/etnologia , Doenças Cardiovasculares/genética , Estudos de Casos e Controles , Mapeamento Cromossômico , Comorbidade , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Frequência do Gene , Marcadores Genéticos , Predisposição Genética para Doença , Genótipo , Humanos , Hiperlipoproteinemia Tipo II/epidemiologia , Hiperlipoproteinemia Tipo II/etnologia , Escore Lod , Masculino , Pessoa de Meia-Idade , Fenótipo , Característica Quantitativa Herdável , Fatores de Risco , Texas/epidemiologia
7.
J Ultrasound ; 26(4): 793-797, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37540347

RESUMO

INTRODUCTION: Open surgical muscle biopsy has traditionally been required for the histological diagnosis of myopathy but requires neurosurgical expertise with a variable diagnostic yield. Ultrasound guided percutaneous approaches are less resource intensive and invasive. This follow-up study aims to assess the diagnostic yield and tolerability of this approach to assess its utility as an adjunct to the traditional open surgical technique. METHODOLOGY: Between March of 2020 and June of 2021, 24 patients underwent a muscle biopsy following discussion at our regional neuromuscular multi-disciplinary team meeting. A consultant musculoskeletal radiologist used a modified Bergstrom needle to obtain a minimum of 2 samples under 500 mmHg of suction and ultrasound guidance. These were followed up to assess the diagnostic yield. A survey was also sent to the patients to assess the tolerability of the procedure. RESULTS: 21 out of the 24 biopsies performed provided diagnostic information. Of these 3 non diagnostic samples were obtained, two were insufficient in size and one consisted of fatty tissue. Of the 21 patients who responded to the survey, 18 rated the procedure as good or excellent with 3 patients rated it as average or poor citing administrative or communication issues rather than procedural. All 5 patients who had previously undergone surgical biopsy expressed a preference for the ultrasound guided percutaneous approach. No patients experienced any complications. CONCLUSION: This follow-up study reinforces the conclusion of its predecessor by highlighting that ultrasound guided percutaneous muscle biopsy is a useful and tolerable adjunct to the traditional surgical technique in investigating muscle disorders.


Assuntos
Doenças Musculares , Humanos , Seguimentos , Doenças Musculares/diagnóstico por imagem , Biópsia por Agulha Fina , Músculos , Biópsia Guiada por Imagem/efeitos adversos , Ultrassonografia de Intervenção/efeitos adversos , Estudos Retrospectivos
8.
Eur J Pharm Biopharm ; 183: 74-91, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36623752

RESUMO

The incidence and prevalence of invasive fungal infections have increased significantly over the last few years, leading to a global health problem due to the lack of effective treatments. Amphotericin B (AmB) and itraconazole (ITR) are two antifungal drugs with different mechanisms of action. In this work, AmB and ITR have been formulated within granules to elicit an enhanced pharmacological effect, while enhancing the oral bioavailability of AmB. A Quality by Design (QbD) approach was utilised to prepare fixed-dose combination (FDC) granules consisting of a core containing AmB with functional excipients, such as inulin, microcrystalline cellulose (MCC), chitosan, sodium deoxycholate (NaDC) and Soluplus® and polyvinyl pyrrolidone (PVP), coated with a polymeric layer containing ITR with Soluplus® or a combination of Poloxamer 188 and hydroxypropyl methyl cellulose-acetyl succinate (HPMCAS). A Taguchi design of experiments (DoE) with 7 factors and 2 levels was carried out to understand the key factors impacting on the physicochemical properties of the formulation followed by a Box-Behnken design with 3 factors in 3 levels chosen to optimise the formulation parameters. The core of the FDC granules was obtained by wet granulation and later coated using a fluidized bed. In vitro antifungal efficacy was demonstrated by measuring the inhibition halo against different species of Candida spp., including C. albicans (24.19-30.48 mm), C. parapsilosis (26.38-27.84 mm) and C. krusei (11.48-17.92 mm). AmB release was prolonged from 3 to 24 h when the AmB granules were coated. In vivo in CD-1 male mice studies showed that these granules were more selective towards liver, spleen and lung compared to kidney (up to 5-fold more selective in liver, with an accumulation of 8.07 µg AmB/g liver after twice-daily 5 days administration of granules coated with soluplus-ITR), resulting in an excellent oral administration option in the treatment of invasive mycosis. Nevertheless, some biochemical alterations were found, including a decrease in blood urea nitrogen (∼17 g/dl) and alanine aminotransferase (<30 U/l) and an increase in the levels of bilirubin (∼0.2 mg/dl) and alkaline phosphatase (<80 U/l), which could be indicative of a liver failure. Once-daily regimen for 10 days can be a promising therapy.


Assuntos
Anfotericina B , Micoses , Masculino , Camundongos , Animais , Anfotericina B/farmacologia , Anfotericina B/química , Antifúngicos/química , Itraconazol , Micoses/tratamento farmacológico , Candida albicans
9.
Pharmaceutics ; 14(11)2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36365143

RESUMO

The International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH), along with the World Health Organization (WHO), has provided a set of guidelines (ICH Q1A-E, Q3A-B, Q5C, Q6A-B) intended to unify the standards for the European Union, Japan, and the United States to facilitate the mutual acceptance of stability data that are sufficient for registration by the regulatory authorities in these jurisdictions. Overall, ICH stability studies involve a drug substance tested under storage conditions and assess its thermal stability and sensitivity to moisture. The long-term testing should be performed over a minimum of 12 months at 25 °C ± 2 °C/60% RH ± 5% RH or at 30 °C ± 2 °C/65% RH ± 5% RH. The intermediate and accelerated testing should cover a minimum of 6 months at 30 °C ± 2 °C/65% RH ± 5% RH (which is not necessary if this condition was utilized as a long-term one) and 40 °C ± 2 °C/75% RH ± 5% RH, respectively. Hence, the ICH stability testing for industrially fabricated medicines is rigorous and tedious and involves a long period of time to obtain preclinical stability data. For this reason, Accelerated Predictive Stability (APS) studies, carried out over a 3-4-week period and combining extreme temperatures and RH conditions (40-90 °C)/10-90% RH, have emerged as novel approaches to predict the long-term stability of pharmaceutical products in a more efficient and less time-consuming manner. In this work, the conventional ICH stability studies versus the APS approach will be reviewed, highlighting the advantages and disadvantages of both strategies. Furthermore, a comparison of the stability requirements for the commercialization of industrially fabricated medicines versus extemporaneous compounding formulations will be discussed.

10.
BJR Case Rep ; 6(1): 20190072, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32201613

RESUMO

Posterior rectus sheath hernia is a truly rare finding, with only 11 documented cases since the first report in 1937. A posterior rectus sheath hernia is herniation of bowel and/or omentum through the posterior portion of the rectus sheath, but not through any other structure. This can only occur medial to the spigelian fascia, differentiating it from a spigelian hernia. Previous missed cases have led to complications such as bowel incarceration, obstruction or even strangulation and have required surgical intervention. In this case report, we describe an incidental finding of a non-complicated posterior rectus sheath hernia in an 83-year-old male. Annotated cross-sectional imaging provides anatomical context that is not widely available in the existing literature. Due to its rarity and potential complications, it is also important to report this case in order to enhance the evidence base for posterior rectus sheath hernia and to familiarize this uncommon condition to radiologists, clinicians and surgeons.

11.
Pharmaceutics ; 12(11)2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-33233520

RESUMO

The aim of this study was to investigate the use of a three-fluid atomising nozzle in a lab-scale spray dryer for the production of dry powders intended for pulmonary delivery. Powders were composed of salbutamol sulphate and theophylline in different weight ratios. The three-fluid nozzle technology enabled powders containing a high theophylline content to be obtained, overcoming the problems associated with its relatively low solubility, by pumping two separate feed solutions (containing the two different active pharmaceutical ingredients (APIs)) into the spray dryer via two separate nozzle channels at different feed rates. The final spray-dried products were characterized in terms of morphology, solid-state properties and aerosolization performance, and were compared with an equivalent formulation prepared using a standard two-fluid atomising nozzle. Results confirmed that most of the powders made using the three-fluid atomising nozzle met the required standards for a dry powder inhaler formulation in terms of physical characteristics; however, aerosolization characteristics require improvement if the powders are to be considered suitable for pulmonary delivery.

12.
Clin Cancer Res ; 14(2): 370-8, 2008 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-18223211

RESUMO

PURPOSE: Human invasive breast cancers (IBC) show enormous histologic and biological diversity. This study comprehensively evaluated diversity in ductal carcinoma in situ (DCIS), the immediate precursors of IBCs. EXPERIMENTAL DESIGN: The extent of diversity for conventional histologic grade and standard prognostic biomarkers assessed by immunohistochemistry was evaluated in a series of pure DCIS (n = 200) compared with a contemporaneous series of IBCs (n = 200). A subset of the DCIS (n = 25) was evaluated by DNA microarrays for the presence of luminal, basal, and erbB2 intrinsic subtypes. The extent of diversity within individual cases of DCIS (n = 120) was determined by assessing multiple regions independently for histologic (nuclear) grade and several biomarkers by immunohistochemistry, which approximate microarrays in determining intrinsic subtypes. RESULTS: DCIS showed a broad distribution of conventional histologic grades and standard biomarkers ranging from well to poorly differentiated, nearly identical to IBCs. Microarrays showed the same intrinsic subtypes in DCIS as in IBCs. However, higher resolution analysis showed that multiple histologic grades, biomarker phenotypes, and intrinsic subtypes often coexist within the same DCIS, and these diverse regions probably compete for dominance. Diversity within cases of DCIS was highly correlated with mutated p53 (P = 0.0007). CONCLUSIONS: These results support the hypothesis that poorly differentiated DCIS gradually evolve from well-differentiated DCIS by randomly acquiring genetic defects resulting in increasingly abnormal cellular features. This diversity is amplified by defects resulting in genetic instability (e.g., p53 mutation), and the alterations are propagated to IBC in a manner independent of progression to invasion.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/fisiopatologia , Carcinoma Ductal de Mama/fisiopatologia , Carcinoma Intraductal não Infiltrante/fisiopatologia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/genética , Carcinoma Ductal de Mama/patologia , Carcinoma Intraductal não Infiltrante/classificação , Carcinoma Intraductal não Infiltrante/genética , Carcinoma Intraductal não Infiltrante/patologia , Progressão da Doença , Fator de Transcrição GATA3/metabolismo , Genes erbB-2 , Genes p53 , Humanos , Mutação , Análise de Sequência com Séries de Oligonucleotídeos , Proteína Supressora de Tumor p53/metabolismo
13.
Eur J Pharm Biopharm ; 144: 139-153, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31536784

RESUMO

Trehalose is commonly used as a protein stabilizer in spray dried protein formulations delivered via the pulmonary route. Spray dried trehalose formulations are highly hygroscopic, which makes them prone to deliquescence and recrystallization when exposed to moisture, leading to impairment in aerosolization performance. The main aim of this study was to investigate and compare the effect of hydrophobic amino acids (i.e. L-leucine and L-isoleucine) in enhancing aerosolization performance and in mitigating moisture-induced changes in spray dried trehalose formulations. Trehalose was spray dried with 20-60% w/w of amino acid (i.e. L-leucine or L-isoleucine). The spray dried formulations were stored at 25 °C/50% RH for 28 days. Solid state characterization and in vitro aerosolization performance studies were performed on the spray dried formulations before and after storage. The addition of 20-60% w/w of amino acid (i.e. L-leucine or L-isoleucine) improved the emitted fractions of spray dried trehalose formulations from a dry powder inhaler. However, ≥ 40% w/w of L-leucine/L-isoleucine was needed to prevent recrystallization of trehalose in the formulations when exposed to 25 °C/50% RH for 28 days. X-ray photoelectron spectroscopy (XPS) demonstrated that samples with 40-60% w/w L-isoleucine had more amino acid on the surfaces of the particles compared to their L-leucine counterparts. This may explain the greater ability of the L-isoleucine (40-60% w/w) samples to cope with elevated humidity compared to L-leucine samples of the same concentrations, as observed in the dynamic vapour sorption (DVS) studies. In conclusion, this study demonstrated that both L-leucine and L-isoleucine were effective in enhancing aerosolization performance and mitigating moisture-induced reduction in aerosolization performance in spray dried trehalose formulations. L-isoleucine proved to be superior to L-leucine in terms of its moisture protectant effect when incorporated at the same concentration in the formulations.


Assuntos
Aminoácidos/química , Trealose/química , Administração por Inalação , Aerossóis/química , Química Farmacêutica/métodos , Composição de Medicamentos/métodos , Inaladores de Pó Seco/métodos , Umidade , Interações Hidrofóbicas e Hidrofílicas , Leucina/química , Pós/química , Molhabilidade/efeitos dos fármacos
14.
Int J Pharm ; 551(1-2): 241-256, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30223079

RESUMO

The comparison of spray drying versus hot melt extrusion (HME) in order to formulate amorphous solid dispersions has been widely studied. However, to the best of our knowledge, the use of both techniques to form cocrystals within a carrier excipient has not previously been compared. The combination of ibuprofen (IBU) and isonicotinamide (INA) in a 1:1 M ratio was used as a model cocrystal. A range of pharmaceutical excipients was selected for processing - mannitol, xylitol, Soluplus and PVP K15. The ratio of cocrystal components to excipient was altered to assess the ratios at which cocrystal formation occurs during spray drying and HME. Hansen Solubility Parameter (HSP) and the difference in HSP between the cocrystal and excipient (ΔHSP) was employed as a tool to predict cocrystal formation. During spray drying, when the difference in HSP between the cocrystal and the excipient was large, as in the case of mannitol (ΔHSP of 18.3 MPa0.5), a large amount of excipient (up to 50%) could be incorporated without altering the integrity of the cocrystal, whereas for Soluplus and PVP K15, where the ΔHSP was 2.1 and 1.6 MPa0.5 respectively, the IBU:INA cocrystal alone was only formed at a very low weight ratio of excipient, i.e. cocrystal:excipient 90:10. Remarkably different results were obtained in HME. In the case of Soluplus and PVP K15, a mixture of cocrystal with single components (IBU and INA) was obtained even when only 10% excipient was included. In conclusion, in order to reduce the number of unit operations required to produce a final pharmaceutical product, spray drying showed higher feasibility over HME to produce cocrystals within a carrier excipient.


Assuntos
Composição de Medicamentos/métodos , Excipientes/química , Cristalização , Dessecação , Temperatura Alta , Ibuprofeno/química , Manitol/química , Niacinamida/química , Polietilenoglicóis/química , Polivinil/química , Pirrolidinas/química , Xilitol/química
15.
Eur J Pharm Biopharm ; 124: 13-27, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29196273

RESUMO

Engineering of pharmaceutical cocrystals is an advantageous alternative to salt formation for improving the aqueous solubility of hydrophobic drugs. Although, spray drying is a well-established scale-up technique in the production of cocrystals, several issues can arise such as sublimation or stickiness due to low glass transition temperatures of some organic molecules, making the process very challenging. Even though, fluidised bed spray coating has been successfully employed in the production of amorphous drug-coated particles, to the best of our knowledge, it has never been employed in the production of cocrystals. The feasibility of this technique was proven using three model cocrystals: sulfadimidine (SDM)/4-aminosalicylic acid (4ASA), sulfadimidine/nicotinic acid (NA) and ibuprofen (IBU)/ nicotinamide (NAM). Design of experiments were performed to understand the critical formulation and process parameters that determine the formation of either cocrystal or coamorphous systems for SDM/4ASA. The amount and type of binder played a key role in the overall solid state and in vitro performance characteristics of the cocrystals. The optimal balance between high loading efficiencies and high degree of crystallinity was achieved only when a binder: cocrystal weight ratio of 5:95 or 10:90 was used. The cocrystal coated beads showed an improved in vitro-in vivo performance characterised by: (i) no tendency to aggregate in aqueous media compared to spray dried formulations, (ii) enhanced in vitro activity (1.8-fold greater) against S. aureus, (iii) larger oral absorption and bioavailability (2.2-fold higher Cmax), (iv) greater flow properties and (v) improved chemical stability than cocrystals produced by other methods derived from the morphology and solid nature of the starter cores.


Assuntos
Ácido Aminossalicílico/química , Antibacterianos/química , Sulfametazina/química , Administração Oral , Aerossóis , Ácido Aminossalicílico/administração & dosagem , Ácido Aminossalicílico/farmacocinética , Animais , Antibacterianos/administração & dosagem , Antibacterianos/farmacocinética , Disponibilidade Biológica , Cristalização , Preparações de Ação Retardada , Combinação de Medicamentos , Composição de Medicamentos , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Estudos de Viabilidade , Ibuprofeno/administração & dosagem , Ibuprofeno/química , Camundongos , Niacina/administração & dosagem , Niacina/química , Niacinamida/administração & dosagem , Niacinamida/química , Solubilidade , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Sulfametazina/administração & dosagem , Sulfametazina/farmacocinética , Tecnologia Farmacêutica/métodos
16.
Clin Cancer Res ; 12(17): 5047-54, 2006 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-16951220

RESUMO

PURPOSE: Inflammatory breast cancer (IBC) is associated with very poor prognosis. The aims of this study are (a) to prospectively identify differential gene expression patterns associated with IBC and (b) to confirm these pathways using tissue arrays. EXPERIMENTAL DESIGN: For gene expression analysis, IBC (n=14) was clinically defined as rapid-onset cancer associated with erythema and skin changes, whereas non-IBC patients (n=20) had stage III breast cancers, and cDNA analysis was carried out using the Affymetrix (Santa Clara, CA) HG-U133A microarrays. Tissue arrays were constructed from paraffin-embedded material, and the molecular phenotype of 75 IBC was compared with results from>2,000 non-IBC. RESULTS: Gene expression analyses indicated that IBC has higher expression of genes associated with increased metabolic rate, lipid signaling, and cell turnover relative to non-IBC tumors. Consistent with the expression analysis, IBC had statistically higher Ki-67 (93% versus 11%; P<0.001). BAX expression, reflecting increased apoptosis and cell turnover, was significantly uniformly higher in almost all IBC (98% versus 66%; P<0.05), whereas the expression of Bcl-2 was not significantly different. IBC tumors were more likely to be steroid hormone receptor negative (estrogen receptor, 49% versus 30%; P=0.002; progesterone receptor, 68% versus 42%; P=0.001). The expression of tyrosine kinases was not significantly different. E-cadherin was found to be expressed in 87% of IBC, whereas the expression p53 was not significantly different. CONCLUSION: This study is one of the largest molecular analyses of IBC. Both IBC and non-IBC are genetically heterogeneous with consistent differences in the molecular phenotype of IBC.


Assuntos
Neoplasias da Mama/genética , Perfilação da Expressão Gênica , Heterogeneidade Genética , Neoplasias da Mama/patologia , Proliferação de Células , Análise por Conglomerados , Feminino , Humanos , Imuno-Histoquímica , Inflamação , Estadiamento de Neoplasias , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Linhagem , Fenótipo
17.
Int J Pharm ; 531(1): 191-204, 2017 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-28801109

RESUMO

The development of solid dosage forms and manufacturing processes are governed by complex physical properties of the powder and the type of pharmaceutical unit operation the manufacturing processes employs. Suitable powder flow properties and compactability are crucial bulk level properties for tablet manufacturing by direct compression. It is also generally agreed that small scale powder flow measurements can be useful to predict large scale production failure. In this study, predictive multilinear regression models were effectively developed from critical material properties to estimate static powder flow parameters from particle size distribution data for a single component and for binary systems. A multilinear regression model, which was successfully developed for ibuprofen, also efficiently predicted the powder flow properties for a range of batches of two other active pharmaceutical ingredients processed by the same manufacturing route. The particle size distribution also affected the compactability of ibuprofen, and the scope of this work will be extended to the development of predictive multivariate models for compactability, in a similar manner to the approach successfully applied to flow properties.


Assuntos
Excipientes/análise , Pós/análise , Tecnologia Farmacêutica , Química Farmacêutica , Tamanho da Partícula , Comprimidos
18.
J Clin Oncol ; 23(6): 1169-77, 2005 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-15718313

RESUMO

PURPOSE: Chemotherapy for operable breast cancer decreases the risk of death. Docetaxel is one of the most active agents in breast cancer, but resistance or incomplete response is frequent. PATIENTS AND METHODS: Core biopsies from 24 patients were obtained before treatment with neoadjuvant docetaxel (four cycles, 100 mg/m(2) every 3 weeks), and response was assessed after chemotherapy. After 3 months of neoadjuvant chemotherapy, surgical specimens (n = 13) were obtained, and laser capture microdissection (LCM; n = 8) was performed to enrich for tumor cells. From each core, surgical, and LCM specimen, sufficient total RNA (3 to 6 microg) was extracted for cDNA array analysis using the Affymetrix HgU95-Av2 GeneChip (Affymetrix, Santa Clara, CA). RESULTS: From the initial core biopsies, differential patterns of expression of 92 genes correlated with docetaxel response (P = .001). However, the molecular patterns of the residual cancers after 3 months of docetaxel treatment were strikingly similar, independent of initial sensitivity or resistance. This relative genetic homogeneity after treatment was observed in both LCM and non-LCM surgical specimens. The residual tumor after treatment in tumors that were initially sensitive indicates selection of a residual and resistant subpopulation of cells. The gene expression pattern was populated by genes involved in cell cycle arrest at G(2)M (eg, mitotic cyclins and cdc2) and survival pathways involving the mammalian target of rapamycin. CONCLUSION: A specific and consistent gene expression pattern was found in residual tumors after docetaxel treatment. These profiles provide therapeutic targets that could lead to improved treatment.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Resistencia a Medicamentos Antineoplásicos/genética , Perfilação da Expressão Gênica , Taxoides/uso terapêutico , Adulto , Quimioterapia Adjuvante , Docetaxel , Feminino , Humanos , Pessoa de Meia-Idade , Terapia Neoadjuvante , Análise de Sequência com Séries de Oligonucleotídeos
19.
Eur J Pharm Sci ; 81: 181-8, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26493586

RESUMO

Co-processing an active pharmaceutical ingredient (API) with a low Tg excipient has been previously reported to be an effective strategy for preventing drug amorphisation on milling. This technique relies on the ability of the excipient to form a molecular dispersion with the amorphous API during the milling process. The presence of the excipient within the amorphous phase induces a reduction of the Tg. Hence, the molecular dispersion becomes less stable than the amorphous API alone and recrystallises upon milling. The objective of this study was to develop a screening method for the selection of suitable excipients to prevent amorphisation, based on two criteria: the Tg of the excipient and the solubility of the excipient in the amorphous API. The ability of the excipients to induce Tg reduction was first assessed by measuring the Tg of the amorphous composite by thermal analysis and comparing it with that of the pure API (griseofulvin). A predicted ability for mitigation of amorphisation upon milling was then deduced from these observations for each excipient and assessed against experimental results. The same excipients were then studied with regard to their expected solubility in another amorphous API (budesonide) by Hildebrand solubility parameter calculations in order to evaluate their capacity to form an amorphous composite with the drug. The predicted effects of the excipients on comilling were compared with the amorphous content of the processed API. The screening method as applied to both APIs showed good agreement with the experimental results and were shown to be efficient for the selection of the most appropriate excipient. This approach revealed that the two key parameters involved are the Tg of the excipient and the ability of the API to form an amorphous molecular dispersion with the excipients. This work confirms and completes our previously published results on the mitigation of the amorphisation by comilling with low Tg excipients and constitutes the first report of the use of a polymeric additive for this purpose.


Assuntos
Excipientes/química , Budesonida/química , Química Farmacêutica , Composição de Medicamentos , Griseofulvina/química , Temperatura de Transição
20.
J Pharm Pharmacol ; 68(5): 665-77, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26408342

RESUMO

OBJECTIVES: Cocrystallization of sulfadimidine (SDM) with suitable coformers, such as 4-aminosalicylic acid (4-ASA), combined with changes in the crystal habit can favourably alter its physicochemical properties. The aim of this work was to engineer SDM : 4-ASA cocrystals with different habits to investigate the effect on dissolution, and the derived powder properties of flow and compaction. METHODS: Cocrystals were prepared in a 1 : 1 molar ratio by solvent evaporation using ethanol (habit I) or acetone (habit II), solvent evaporation followed by grinding (habit III) and spray drying (habit IV). KEY FINDINGS: Powder X-ray diffraction showed Bragg peak position was the same in all the solid products. The peak intensity varied, indicating different preferred crystal orientation confirmed by SEM micrographs: large prismatic crystals (habit I), large plate-like crystals (habit II), small cube-like crystals (habit III) and microspheres (habit IV). The habit III exhibited the fasted dissolution rate; however, it underwent a polymorphic transition during dissolution. Habits I and IV exhibited the highest Carr's compressibility index, indicating poor flowability. However, habits II and III demonstrated improved flow. Spray drying resulted in cocrystals with improved compaction properties. CONCLUSIONS: Even for cocrystals with poor pharmaceutical characteristics, a habit can be engineered to alter the dissolution, flowability and compaction behaviour.


Assuntos
Acedapsona/química , Ácido Aminossalicílico/química , Anti-Infecciosos/química , Acetona/química , Aerossóis , Cristalização , Cristalografia por Raios X , Combinação de Medicamentos , Composição de Medicamentos , Etanol/química , Cinética , Microscopia Eletrônica de Varredura , Modelos Químicos , Modelos Moleculares , Difração de Pó , Pós , Solubilidade , Solventes/química , Propriedades de Superfície , Tecnologia Farmacêutica/métodos
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