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1.
Bioorg Chem ; 147: 107372, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38653152

RESUMEN

Joining the global demand for the discovery of potent NSAIDs with minimized ulcerogenic effect, new pyrazole clubbed thiazole derivatives 5a-o were designed and synthesized. The new derivatives were initially evaluated for their analgesic activity. Eight compounds 5a, 5c, 5d, 5e, 5f, 5h, 5m, and 5o showed higher activity than Indomethacin (potency = 105-130 % vs. 100 %). Subsequently, they were picked for further evaluation of their anti-inflammatory activity, ulcerogenic liability as well as toxicological studies. Derivatives 5h and 5m showed a potential % edema inhibition after 3 h (79.39 % and 72.12 %, respectively), with a promising safety profile and low ulcer indices (3.80 and 3.20, respectively). The two compounds 5h and 5m were subjected to in vitro COX-1 and COX-2 inhibition assay. The candidate 5h showed nearly equipotent COX-1 inhibition (IC50 = 38.76 nM) compared to the non-selective reference drug Indomethacin (IC50 = 35.72 nM). Compound 5m expressed significant inhibitory activities and a higher COX-2 selectivity index (IC50 = 87.74 nM, SI = 2.05) in comparison with Indomethacin (SI = 0.52), with less selectivity than Celecoxib (SI = 8.31). Simulation docking studies were carried out to gain insights into the binding interaction of compounds 5h and 5m in the vicinity of COX-1 and COX-2 enzymes that illustrated the importance of pyrazole clubbed thiazole core in hydrogen bonding interactions. The thiazole motif of compounds 5h and 5m exhibited a well orientation toward COX-1 Arg120 key residue by hydrogen bonding interactions. Compound 5h revealed an additional arene-cation interaction with Arg120 that could rationalize its superior COX-1 inhibitory activity. Compounds 5h and 5m overlaid the co-crystallized ligand Celecoxib I differently in the active site of COX-2. Compound 5m showed an enhanced accommodation with binding energy of - 6.13 vs. - 1.70 kcal/mol of compounds 5h. The naphthalene ring of compound 5m adopted the Celecoxib I benzene sulfonamide region that is stabilized by hydrogen-arene interactions with the hydrophobic sidechains of the key residues Ser339 and Phe504. Further, the core structure of compound 5m, pyrazole clubbed thiazole, revealed deeper hydrophobic interactions with Ala513, Leu517 and Val509 residues. Finally, a sensitive and accurate UPLC-MS/MS method was developed for the simultaneous estimation of some selected promising pyrazole derivatives in rat plasma. Accordingly, compounds 5h and 5m were suggested to be promising potent analgesic and anti-inflammatory agents with improved safety profiles and a novel COX isozyme modulation activity.


Asunto(s)
Analgésicos , Antiinflamatorios no Esteroideos , Ciclooxigenasa 2 , Edema , Simulación del Acoplamiento Molecular , Tiazoles , Animales , Masculino , Ratones , Ratas , Analgésicos/farmacología , Analgésicos/química , Analgésicos/síntesis química , Antiinflamatorios no Esteroideos/farmacología , Antiinflamatorios no Esteroideos/química , Antiinflamatorios no Esteroideos/síntesis química , Ciclooxigenasa 1/metabolismo , Ciclooxigenasa 2/metabolismo , Inhibidores de la Ciclooxigenasa/farmacología , Inhibidores de la Ciclooxigenasa/química , Inhibidores de la Ciclooxigenasa/síntesis química , Relación Dosis-Respuesta a Droga , Descubrimiento de Drogas , Edema/tratamiento farmacológico , Edema/inducido químicamente , Estructura Molecular , Pirazoles/química , Pirazoles/farmacología , Pirazoles/síntesis química , Relación Estructura-Actividad , Tiazoles/química , Tiazoles/farmacología , Tiazoles/síntesis química
2.
3.
Thromb J ; 22(1): 12, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38233821

RESUMEN

BACKGROUND: Tissue factor (TF) activity is stringently regulated through processes termed encryption. Post-translational modification of TF and its interactions with various protein and lipid moieties allows for a multi-step de-encryption of TF and procoagulant activation. Membrane-associated guanylate kinase-with inverted configuration (MAGI) proteins are known to regulate the localisation and activity of a number of proteins including cell-surface receptors. METHODS: The interaction of TF with MAGI1 protein was examined as a means of regulating TF activity. MDA-MB-231 cell line was used which express TF and MAGI1, and respond well to protease activated receptor (PAR)2 activation. Proximity ligation assay (PLA), co-immunoprecipitation and pull-down experiments were used to examine the interaction of TF with MAGI1-3 proteins and to investigate the influence of PAR2 activation. Furthermore, by cloning and expressing the PDZ domains from MAGI1, the TF-binding domain was identified. The ability of the recombinant PDZ domains to act as competitors for MAGI1, allowing the induction of TF procoagulant and signalling activity was then examined. RESULTS: PLA and fluorescence microscopic analysis indicated that TF predominantly associates with MAGI1 and less with MAGI2 and MAGI3 proteins. The interaction of TF with MAGI1 was also demonstrated by both co-immunoprecipitation of TF with MAGI1, and co-immunoprecipitation of MAGI1 with TF. Moreover, activation of PAR2 resulted in reduction in the association of these two proteins. Pull-down assays using TF-cytoplasmic domain peptides indicated that the phosphorylation of Ser253 within TF prevents its association with MAGI1. Additionally, the five HA-tagged PDZ domains of MAGI1 were overexpressed separately, and the putative TF-binding domain was identified as PDZ1 domain. Expression of this PDZ domain in cells significantly augmented the TF activity measured both as thrombin-generation and also TF-mediated proliferative signalling. CONCLUSIONS: Our data indicate a stabilising interaction between TF and the PDZ-1 domain of MAGI1 and demonstrate that the activation of PAR2 disrupts this interaction. The release of TF from MAGI1 appears to be an initial step in TF de-encryption, associated with increased TF-mediated procoagulant and signalling activities. This mechanism is also likely to lead to further interactions and modifications leading to further enhancement of procoagulant activity, or the release of TF.

4.
Clin Med Insights Oncol ; 16: 11795549211036898, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35125900

RESUMEN

Radiotherapy-related fibrosis remains one of the most challenging treatment related side effects encountered by patients with head and neck cancer. Several established and ongoing novel therapies have been studied with paucity of data in how to best treat these patients. This review aims to provide researchers and health care providers with a comprehensive review on the presentation, etiology, and therapeutic options for this serious condition.

5.
J AOAC Int ; 105(4): 957-963, 2022 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-35167683

RESUMEN

BACKGROUND: Reverse phase liquid chromatography (RP-LC) is considered the most extensively used chromatographic technique in drug separation and quantification, yet its routine use shows increasing environmental challenges about energy consumption, solvent used, and waste engendered. From this perception, efforts for greening the developed RP-LC methods are focused on using green solvents and reducing the amount of solvent used and waste produced. OBJECTIVE: The target of this work is to develop an eco-friendly RP-LC method for the synchronous separation of six widely used drugs in the treatment of cerebrovascular and vestibular disorders, namely neurotropic piracetam, antihistamines dimenhydrinate, cinnarizine, and fluranizine, and vasodilators vincamine and vinpocetine. METHOD: Separation and quantification are accomplished at ambient temperature by isocratic elution mode using acetonitrile-0.2% triethylamine (85:15 by volume) as a mobile phase at a flow rate of 1.5 mL/min on a Hypersil C18 column. UV detection and quantification are carried out at 225 nm. RESULTS: The method is fully validated per ICH guidelines, where all analytical parameters are within the acceptable range (r > 0.9999), accuracy (≥99.55%), and precision (0.02-0.97%). CONCLUSIONS: The method is applied for the routine analysis of the cited drugs in their single and combined drug products, and it is considered excellent in terms of greenness with respect to Eco-Scale assessment. HIGHLIGHTS: As the routine use of the RP-LC technique shows increasing environmental challenges, efforts for greening are attempted focusing on the use of green solvents and reducing the amount of solvent used and waste produced. A simple eco-friendly RP-LC method for the synchronous separation of six widely used drugs in the treatment of cerebrovascular and vestibular disorders is developed. The method is fully validated per ICH guidelines, where all analytical parameters are within the acceptable range. The method is applied for the routine analysis of the cited drugs in their single and combined drug products.


Asunto(s)
Cromatografía de Fase Inversa , Cromatografía Líquida de Alta Presión/métodos , Cromatografía de Fase Inversa/métodos , Solventes/química
6.
J Chromatogr Sci ; 60(9): 832-839, 2022 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-34875682

RESUMEN

From evolution, thin-layer chromatography (TLC) attracts attention as a versatile technique for efficient separation and identification of many drug substances and chemicals. Owing to its simplicity and other outstanding advantages, TLC is extensively used by chromatographers in quantification and purity profiling objectives. In the present study two TLC-Densitometric methods are established and validated for the synchronous estimation of Cinnarizine (Cinn) and Acefyline Heptaminol (Acef) in the presence of Cinn/Acef reported degradation products and Thoephylline (Theo) as Acef potential impurity. The proposed methods are based on densitometric measurements of the spots of Cinn and Acef after separation from their degradation products. Separation is attained on silica gel sheet with dichloromethane: methanol: formic acid as a developing system in ratio: (15, 1, 0.5, by volume) and (15, 0.75, 0.4, by volume) for Cinn (method 1) and Acef (method 2) degradation, consecutively. Quantification is done at 254 nm over concentration ranges of 0.2-1.8 and 2-18 µg/spot for Cinn and Acef; respectively, with mean percentage recoveries of 99.18 ± 0.60/99.84 ± 0.53 and 99.19 ± 0.93/99.66 ± 0.58 for method 1 and method 2; consecutively. The two methods are fully validated and proven to be selective, robust and retained their accuracy in up to 50% of Cinn/Acef reported degradation products and Theo. Moreover, the two methods are applied to a coformulated drug product comprising Cinn and Acef showing satisfactory results. Comparison of the obtained results by the proposed methods with that of the reference ones statistically shows no significant differences.


Asunto(s)
Cinarizina , Heptaminol , Cromatografía en Capa Delgada/métodos , Cinarizina/análisis , Densitometría/métodos , Reproducibilidad de los Resultados
7.
Front Biosci (Landmark Ed) ; 26(10): 752-764, 2021 10 30.
Artículo en Inglés | MEDLINE | ID: mdl-34719203

RESUMEN

Introduction: The restriction of prolyl-protein cis/trans isomerase 1 (Pin1) activity has been shown to prevent the release of tissue factor (TF) leading to the accumulation of the latter protein within the cell. This study tested the ability of novel small molecules to inhibit Pin1, suppress TF activity and release, and induce cellular apoptosis. Methods: Four compounds were designed and synthesised based on modification of 5-(p-methoxyphenyl)-2-methylfuran-3-carbonyl amide and the outcome on MDA-MB-231 and primary cells examined. These compounds contained 3-(2-naphthyl)-D-alanine (4a), D-tryptophan (4b), D-phenylalanine (4c), and D-tyrosine (4d) at the amino-termini. Results: Treatment of cells with compound 4b and 4d reduced the cell-surface TF activity after 60 min on MDA-MB-231 cells. Incubation with compound 4d also reduced TF antigen on the cell surface and its incorporation into microvesicles, while compounds 4a and 4b significantly increased TF release. None of the four compounds significantly altered the total amount of TF antigen or TF mRNA expression. Compound 4b and 4d also suppressed the binding of Pin1 to TF-cytoplasmic domain peptide. However, compound 4d reduced while compound 4b increased the Pin1 isomerase activity. Finally, treatment with compound 4b and 4d reduced the cell numbers, increased nuclear localisation of p53, Bax protein and bax mRNA expression and induced cellular apoptosis in MDA-MB-231 but not primary endothelial cells. Conclusions: In conclusion, we have identified small molecules to regulate the function of TF within cells. Two of these compounds may prove to be beneficial in moderating TF function specifically and restrain TF-mediated tumour growth without detrimental outcomes on normal vascular cells.


Asunto(s)
Antineoplásicos/farmacología , Micropartículas Derivadas de Células , Tromboplastina , Apoptosis , Recuento de Células , Línea Celular Tumoral , Células Endoteliales , Humanos , Peptidilprolil Isomerasa de Interacción con NIMA , Tromboplastina/genética
8.
Sci Rep ; 10(1): 20908, 2020 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-33262514

RESUMEN

Tissue factor (TF) signalling has been associated with alterations in Akt activity influencing cellular survival and proliferation. TF is also shown to induce signalling through activation of the protease activated receptor (PAR)2. Seven cell lines were exposed to recombinant-TF (rec-TF), or activated using a PAR2-agonist peptide and the phosphorylation state of PTEN, and the activities of PTEN and Akt measured. Furthermore, by measuring the association of PTEN with MAGI proteins a mechanism for the induction of signalling by TF was proposed. Short term treatment of cells resulted in de-phosphorylation of PTEN, increased lipid-phosphatase activity and reduced Akt kinase activity in most of the cell lines examined. In contrast, continuous exposure to rec-TF up to 14 days, resulted in lower PTEN antigen levels, enhanced Akt activity and increased rate of cell proliferation. To explore the mechanism of activation of PTEN by TF, the association of "membrane-associated guanylate kinase-with inverted configuration" (MAGI)1-3 proteins with PTEN was assessed using the proximity ligation assay and by co-immunoprecipitation. The interaction of PTEN with all three MAGI proteins was transiently reduced following PAR2 activation and explains the changes in PTEN activity. Our data is first to show that PAR2 activation directly, or through exposure of cells to TF releases PTEN from MAGI proteins and is concurrent with increases in PTEN phosphatase activity. However, prolonged exposure to TF results in the reduction in PTEN antigen with concurrent increase in Akt activity which may explain the aberrant cell survival, proliferation and invasion associated with TF during chronic diseases.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Fosfohidrolasa PTEN/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptor PAR-2/metabolismo , Tromboplastina/metabolismo , Línea Celular Tumoral , Enfermedad Crónica , Activación Enzimática , Ensayo de Inmunoadsorción Enzimática , Humanos , Fosfohidrolasa PTEN/genética , ARN Mensajero/genética , Transducción de Señal
9.
Apoptosis ; 25(1-2): 29-41, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31654241

RESUMEN

Accumulation of tissue factor (TF) within cells leads to cellular apoptosis mediated through p38 and p53 pathways. In this study, the involvement of Src1 in the induction of TF-mediated cell apoptosis, and the mechanisms of Src1 activation were investigated. Human coronary artery endothelial cell (HCAEC) were transfected with plasmids to express the wild-type TF (TFWt-tGFP), or a mutant (Ser253 → Ala) which is incapable of being released from cells (TFAla253-tGFP). The cells were then activated with PAR2-agonist peptide (SLIGKV-NH) and the phosphorylation of Src and Rac, and also the kinase activity of Src were assessed. Transfected cells were also pre-incubated with pp60c Src inhibitor, FAK inhibitor-14, or a blocking anti-ß1-integrin antibody prior to activation and the phosphorylation of p38 as well as cellular apoptosis was examined. Finally, cells were co-transfected with the plasmids, together with a Src1-specific siRNA, activated as above and the cellular apoptosis measured. Activation of PAR2 lead to the phosphorylation of Src1 and Rac1 proteins at 60 min regardless of TF expression. Moreover, Src phosphorylation and kinase activity was prolonged up to 100 min in the presence of TF, with a significantly higher magnitude when the non-releasable TFAla253-tGFP was expressed in HCAEC. Inhibition of Src with pp60c, or suppression of Src1 expression in cells, reduced p38 phosphorylation and prevented cellular apoptosis. In contrast, inhibition of FAK had no significant influence on Src kinase activity or cellular apoptosis. Finally, pre-incubation of cells with an inhibitory anti-ß1-integrin antibody reduced both Src1 activation and cellular apoptosis. Our data show for the first time that the over-activation of Src1 is a mediator of TF-induced cellular apoptosis in endothelial cells through a mechanism that is dependent on its interaction with ß1-integrin.


Asunto(s)
Apoptosis , Células Endoteliales/metabolismo , Integrina beta1/metabolismo , Proteínas Proto-Oncogénicas pp60(c-src)/metabolismo , Tromboplastina/metabolismo , Células Endoteliales/citología , Humanos , Integrina beta1/genética , Fosforilación , Proteínas Proto-Oncogénicas pp60(c-src)/genética , Transducción de Señal , Tromboplastina/genética
10.
J Vis Exp ; (115)2016 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-27684203

RESUMEN

Here we describe a protocol that can be used to study the biophysical microenvironment related to increased thickness and stiffness of the basement membrane (BM) during age-related pathologies and metabolic disorders (e.g. cancer, diabetes, microvascular disease, retinopathy, nephropathy and neuropathy). The premise of the model is non-enzymatic crosslinking of reconstituted BM (rBM) matrix by treatment with glycolaldehyde (GLA) to promote advanced glycation endproduct (AGE) generation via the Maillard reaction. Examples of laboratory techniques that can be used to confirm AGE generation, non-enzymatic crosslinking and increased stiffness in GLA treated rBM are outlined. These include preparation of native rBM (treated with phosphate-buffered saline, PBS) and stiff rBM (treated with GLA) for determination of: its AGE content by photometric analysis and immunofluorescent microscopy, its non-enzymatic crosslinking by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS PAGE) as well as confocal microscopy, and its increased stiffness using rheometry. The procedure described here can be used to increase the rigidity (elastic moduli, E) of rBM up to 3.2-fold, consistent with measurements made in healthy versus diseased human prostate tissue. To recreate the biophysical microenvironment associated with the aging and diseased prostate gland three prostate cell types were introduced on to native rBM and stiff rBM: RWPE-1, prostate epithelial cells (PECs) derived from a normal prostate gland; BPH-1, PECs derived from a prostate gland affected by benign prostatic hyperplasia (BPH); and PC3, metastatic cells derived from a secondary bone tumor originating from prostate cancer. Multiple parameters can be measured, including the size, shape and invasive characteristics of the 3D glandular acini formed by RWPE-1 and BPH-1 on native versus stiff rBM, and average cell length, migratory velocity and persistence of cell movement of 3D spheroids formed by PC3 cells under the same conditions. Cell signaling pathways and the subcellular localization of proteins can also be assessed.


Asunto(s)
Membrana Basal , Neoplasias de la Próstata , Elasticidad , Matriz Extracelular , Humanos , Masculino , Enfermedades Metabólicas , Próstata , Hiperplasia Prostática
11.
Sensors (Basel) ; 15(8): 18724-41, 2015 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-26263989

RESUMEN

Resonant glassy nanostrings have been employed for the detection of biomolecules. These devices offer high sensitivity and amenability to large array integration and multiplexed assays. Such a concept has however been impaired by the lack of stable and biocompatible linker chemistries. Diazonium salt reduction-induced aryl grafting is an aqueous-based process providing strong chemical adhesion. In this work, diazonium-based linker chemistry was performed for the first time on glassy nanostrings, which enabled the bio-functionalization of such devices. Large arrays of nanostrings with ultra-narrow widths down to 10 nm were fabricated employing electron beam lithography. Diazonium modification was first developed on SiCN surfaces and validated by X-ray photoelectron spectroscopy. Similarly modified nanostrings were then covalently functionalized with anti-rabbit IgG as a molecular probe. Specific enumeration of rabbit IgG was successfully performed through observation of downshifts of resonant frequencies. The specificity of this enumeration was confirmed through proper negative control experiments. Helium ion microscopy further verified the successful functionalization of nanostrings.


Asunto(s)
Técnicas Biosensibles/instrumentación , Compuestos de Diazonio/química , Vidrio/química , Nanopartículas/química , Animales , Helio , Inmunoglobulina G/química , Iones , Sondas Moleculares/química , Nanopartículas/ultraestructura , Espectroscopía de Fotoelectrones , Conejos , Compuestos de Silicona/química , Propiedades de Superficie
12.
Anal Chem Insights ; 8: 99-106, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24137049

RESUMEN

Specific stability indicating reverse-phase liquid chromatography (RP-LC) assay method (SIAM) was developed for the determination of cinnarizine (Cinn)/piracetam (Pira) and cinnarizine (Cinn)/heptaminol acefyllinate (Hept) in the presence of the reported degradation products of Cinn. A C18 column and gradient mobile phase was applied for good resolution of all peaks. The detection was achieved at 210 nm and 254 nm for Cinn/Pira and Cinn/Hept, respectively. The responses were linear over concentration ranges of 20-200, 20-1000 and 25-1000 µgmL(-1) for Cinn, Pira, and Hept respectively. The proposed method was validated for linearity, accuracy, repeatability, intermediate precision, and robustness via statistical analysis of the data. The method was shown to be precise, accurate, reproducible, sensitive, and selective for the analysis of Cinn/Pira and Cinn/Hept in laboratory prepared mixtures and in pharmaceutical formulations.

13.
J Pediatr Surg ; 47(12): e51-4, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23217919

RESUMEN

Lymphoepithelial cyst (LEC) of the pancreas is almost always reported as a case report or in small series mostly in male adult patients with vague clinical manifestations and difficult pre-operative diagnosis. Between the years 2007 and 2012, two female children with LEC of the pancreas were operated on at the Children's Surgical Unit of Murtala Mohammad Specialist Hospital, Kano in northern Nigeria. Satisfactory outcomes were achieved after distal pancreatectomy and splenectomy in one and a Whipple procedure in the other. This benign lesion of the pancreas should be considered in the differential diagnosis of cystic lesions of the pancreas in children.


Asunto(s)
Linfocele/patología , Pancreatectomía/métodos , Quiste Pancreático/patología , Quiste Pancreático/cirugía , Biopsia con Aguja , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Inmunohistoquímica , Laparotomía/métodos , Linfocele/diagnóstico por imagen , Linfocele/cirugía , Nigeria , Quiste Pancreático/diagnóstico por imagen , Medición de Riesgo , Resultado del Tratamiento , Ultrasonografía Doppler
14.
Mol Cell Biochem ; 366(1-2): 269-75, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22527932

RESUMEN

Breast cancer (BC) is the most common neoplasm among women in most developed countries, including Egypt. Elevated levels of certain proteins in human BC are associated with unfavorable prognosis and progressive stages of the disease. The aim of our study was to evaluate the protein expression profile and prognostic significance of cyclooxygenase-2 (COX-2), matrix metalloproteinase-2 (MMP-2), MMP-9 and membrane type 1-MMP (MT1-MMP) and their interaction in operable BC patients. The protein expression of COX-2, MMP-2 and MT1-MMP were evaluated by western blot technique, whereas enzymatic activity of MMP-2 and MMP-9 was determined by zymography in 47 breast cancer patients as well as normal adjacent tissues. Also, the correlation between these proteins and age, tumor size, LN stage, TNM stage, estrogen receptor, progesterone receptor, disease-free survival, and overall survival (OS) has been investigated. As compared to adjacent normal tissues, COX-2, MMP-2 and MT1-MMP were over-expressed in 43, 64, and 60 % of tumor tissues, respectively. In the same pattern, the activity of MMP-2 (62 %) and MMP-9 (45 %) was elevated in BC tissues. Multivariate analysis showed a positive correlation between the protein expression of COX-2, MMP-2, and MT1-MMP and the activity of MMP-2 and MMP-9 in BC patients. However, the enzymatic activity showed no correlation with clinicopathological features. This study confirms the preclinical evidence that COX-2 increased the expression of MT1-MMP, which in turn activates MMP-2. The lack of correlation with clinicopathological features, OS or disease-free survival ascertains the complexity of tumor progression and metastasis with many pro- and counter regulatory factors.


Asunto(s)
Neoplasias de la Mama/enzimología , Carcinoma Ductal de Mama/enzimología , Ciclooxigenasa 2/metabolismo , Metaloproteinasa 14 de la Matriz/metabolismo , Metaloproteinasa 2 de la Matriz/metabolismo , Adulto , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Carcinoma Ductal de Mama/mortalidad , Carcinoma Ductal de Mama/patología , Femenino , Humanos , Estimación de Kaplan-Meier , Metaloproteinasa 9 de la Matriz/metabolismo , Persona de Mediana Edad , Estadificación de Neoplasias , Carga Tumoral
15.
AAPS J ; 13(1): 30-43, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21057906

RESUMEN

Dry powder inhaler formulations comprising commercial lactose-drug blends can show restricted detachment of drug from lactose during aerosolisation, which can lead to poor fine particle fractions (FPFs) which are suboptimal. The aim of the present study was to investigate whether the crystallisation of lactose from different ethanol/butanol co-solvent mixtures could be employed as a method of altering the FPF of salbutamol sulphate from powder blends. Lactose particles were prepared by an anti-solvent recrystallisation process using various ratios of the two solvents. Crystallised lactose or commercial lactose was mixed with salbutamol sulphate and in vitro deposition studies were performed using a multistage liquid impinger. Solid-state characterisation results showed that commercial lactose was primarily composed of the α-anomer whilst the crystallised lactose samples comprised a α/ß mixture containing a lower number of moles of water per mole of lactose compared to the commercial lactose. The crystallised lactose particles were also less elongated and more irregular in shape with rougher surfaces. Formulation blends containing crystallised lactose showed better aerosolisation performance and dose uniformity when compared to commercial lactose. The highest FPF of salbutamol sulphate (38.0 ± 2.5%) was obtained for the lactose samples that were crystallised from a mixture of ethanol/butanol (20:60) compared to a FPF of 19.7 ± 1.9% obtained for commercial lactose. Engineered lactose carriers with modified anomer content and physicochemical properties, when compared to the commercial grade, produced formulations which generated a high FPF.


Asunto(s)
Butanoles/química , Inhaladores de Polvo Seco/instrumentación , Etanol/química , Excipientes/química , Lactosa/química , Aerosoles , Albuterol/administración & dosificación , Albuterol/química , Broncodilatadores/administración & dosificación , Broncodilatadores/química , Rastreo Diferencial de Calorimetría , Química Farmacéutica , Cromatografía Líquida de Alta Presión , Cristalización , Sistemas de Liberación de Medicamentos , Procesamiento de Imagen Asistido por Computador , Microscopía de Fuerza Atómica , Microscopía Electrónica de Rastreo , Tamaño de la Partícula , Polvos , Espectroscopía Infrarroja por Transformada de Fourier
16.
Colloids Surf B Biointerfaces ; 81(1): 96-109, 2010 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-20674291

RESUMEN

The co-grinding technique is one of the most effective methods for improving the dissolution rate of poorly water-soluble drugs and it is superior to other approaches from an economical as well as an environmental stand point, as the technique does not require any toxic organic solvents. The present work is an attempt to use d-glucosamine HCl (G-HCl) as a potential excipient to improve dissolution rate of carbamazepine (CBZ) from physical mixtures and co-grinding formulations. The effect of order of grinding on dissolution of CBZ was also investigated. Co-ground of drug and G-HCL were prepared using different ratios using ball mill. The samples were subjected to different grinding times. In order to investigate the effect of grinding process on dissolution behaviour of CBZ, the drug was ground separately in the absence of glucosamine. Then the mixture of ground CBZ and un-ground d-glucosamine HCl were prepared. Physical mixtures of CBZ and G-HCl were also prepared for comparison. The properties of prepared co-ground systems and physical mixtures were studied using a dissolution tester, FT-IR, SEM, XRPD, and DSC. These results showed that the presence of glucosamine can increase dissolution rate of CBZ compared to pure CBZ. The results showed the order of grinding had a big impact on the dissolution performance of CBZ formulations containing glucosamine. All dissolution profiles generally showed that the fastest dissolution rate was obtained when ground CBZ was mixed with un-ground glucosamine. This was closely followed by the co-grinding of CBZ with glucosamine where lower grinding times showed the fastest dissolution. XRPD showed that the grinding of CBZ can reduce the percentage crystallinity of drug crystals. DSC study of ground CBZ showed that the grinding induced polymorphism transformations in the CBZ crystals and the limit and type of these transformations were related to the grinding time.


Asunto(s)
Carbamazepina/química , Excipientes/química , Glucosamina/química , Tecnología Farmacéutica/métodos , Rastreo Diferencial de Calorimetría , Composición de Medicamentos/métodos , Tamaño de la Partícula , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
17.
Int J Biol Markers ; 25(2): 69-74, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20586027

RESUMEN

PURPOSE: To analyze the behavior of matrix metalloproteinases (MMPs) in their active state in patients with bladder cancer. METHOD: A retrospective study of 50 patients with localized bladder cancer who underwent tumor resection between June 2006 and June 2007 at the National Cancer Institute in Cairo, Egypt was carried out. Tissue samples were collected and the expression of membrane type 1 (MT1) and type 2 (MT2) MMPs was determined by Western blotting. Gelatinase A (MMP-2) activity was estimated by zymographic analysis in tissue samples of each patient and the values were correlated with clinical tumor stage and lymph node status. RESULT: The behavior of MMP-2 showed statistical significance in 90% of tumor tissues compared with 22% of adjacent normal tissues (p<0.001). MT1-MMP was expressed in 88% of tumor tissues compared with 24% of normal tissues (p<0.001); MT2-MMP was expressed in 74% of tumor tissues compared with 12% of normal tissues (p<0.001). While there was a highly significant association between MMP-2 activity and MT1-MMP expression in tumor tissues (p<0.001), there was a moderately significant association between MMP-2 activity and MT2-MMP expression (p=0.018). The results also revealed an association between MT1-MMP and MT2-MMP expression in tumor tissues (p<0.001). MMP-2 activity and MT2-MMP expression in tumor tissues were statistically associated with high tumor stage (p=0.039 and p=0.014, respectively), while the expression of MT1-MMP showed no association with tumor stage (p=0.139). CONCLUSION: MMP-2 activity is associated with an increase in MT2-MMP expression and with lymph node metastasis. No association was found between MT1-MMP expression and lymph node metastasis.


Asunto(s)
Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Transicionales/metabolismo , Metaloproteinasa 14 de la Matriz/metabolismo , Metaloproteinasa 15 de la Matriz/metabolismo , Metaloproteinasa 2 de la Matriz/metabolismo , Neoplasias de la Vejiga Urinaria/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/patología , Carcinoma de Células Transicionales/patología , Activación Enzimática , Femenino , Humanos , Ganglios Linfáticos/metabolismo , Ganglios Linfáticos/patología , Metástasis Linfática , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Valor Predictivo de las Pruebas , Pronóstico , Estudios Retrospectivos , Neoplasias de la Vejiga Urinaria/patología
18.
Colloids Surf B Biointerfaces ; 76(1): 170-8, 2010 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-19945828

RESUMEN

The solid dispersion technique is the most effective method for improving the dissolution rate of poorly water-soluble drugs, however this is reliant on a suitable carrier and solvent being selected. The work presented explores D-glucosamine HCl (G-HCl) as a potential hydrophilic carrier to improve dissolution rate of a poorly water-soluble drug, carbamazepine (CBZ), from physical mixtures and solid dispersion formulations. The effect of different solvents in the preparation of solid dispersion formulations was also investigated. Solid dispersions of the drug and G-HCl were prepared using different ratios by the conventional solvent evaporation method. Different solvents (ethanol, acetone and water) were used as second variable in the preparation of solid dispersions. Physical mixtures of CBZ and G-HCl were also prepared for comparison. The properties of all solid dispersions and physical mixtures were studied using a dissolution tester, FT-IR, SEM and DSC. These results showed that the presence of glucosamine can increase dissolution rate of CBZ compared to pure CBZ. All solid dispersions of CBZ-G-HCl showed considerably a higher dissolution rate than the corresponding physical mixtures. The presence of water during preparation of the solid dispersions reduced the dissolution rate of CBZ due to formation of carbamazepine dihydrate during the preparation of solid dispersion, as proved by DSC and FT-IR studies. To facilitate comparison, the dissolution efficiency was calculated for solid dispersions prepared with different solvents and the dissolution efficiency can generally be ranked as follows: ethanol>acetone>ethanol-water>acetone-water when the ratios of drug to carrier were 4:1 and 2:1. It has thus been shown that the use of G-HCl in solid dispersion formulations can significantly enhance the dissolution rate of poorly water-soluble drugs such as carbamazepine. This amino sugar could be used as a new carrier in solid dispersion formulations and would have significant commercial potential.


Asunto(s)
Carbamazepina/química , Portadores de Fármacos/química , Glucosamina/química , Preparaciones Farmacéuticas/química , Solubilidad , Agua/química , Rastreo Diferencial de Calorimetría , Formas de Dosificación , Cinética , Tamaño de la Partícula , Espectroscopía Infrarroja por Transformada de Fourier
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