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1.
Child Adolesc Psychiatr Clin N Am ; 32(3): 631-653, 2023 07.
Article in English | MEDLINE | ID: mdl-37201972

ABSTRACT

The literature on anxiety in Black, Indigenous, and other persons of color youth is a developing area. This article highlights distinct areas for the clinician to consider in working with these populations. We highlight prevalence and incidence, race-related stress, social media, substance use, spirituality, the impact of social determinants of health (including COVID-19 and the Syndemic), as well as treatment considerations. Our aim is to contribute to the readers' developing cultural humility.


Subject(s)
COVID-19 , Humans , Child , Adolescent , Anxiety/drug therapy , Anxiety/epidemiology , Anxiety Disorders/drug therapy , Anxiety Disorders/epidemiology , Spirituality
2.
Assay Drug Dev Technol ; 18(6): 282-294, 2020.
Article in English | MEDLINE | ID: mdl-32881580

ABSTRACT

The objective of the present investigation is to enhance the dissolution and flow properties of raloxifene hydrochloride (RXH), a biopharmaceutical classification system class II drug. Melt dispersion of RXH with polyethylene glycol (PEG) 6000 was prepared by the fusion method. The melt dispersion was then adsorbed onto a porous adsorbent, Neusilin, by the melt adsorption method. Response surface methodology was employed to establish the design space for formulation variables such as the ratio of RXH to PEG 6000 in melt dispersion and amount of porous adsorbent to melt dispersion. Differential scanning calorimetry, scanning electron microscopy, X-ray diffraction, Fourier-transform infrared spectroscopy, and accelerated stability techniques were utilized to characterize formulations. Negative Gibbs free energy values indicated spontaneous solubilization of RXH in PEG 6000. The time required for 80% of drug release from optimized formulation was <20 min compared with plain RXH. Accelerated stability studies confirmed the stabilization of amorphous melt dispersion in nanopores (nanoconfinement) of inorganic silicate Neusilin. Melt dispersion, adsorbed on porous carriers, is a promising technique to improve the dissolution characteristic as well as flow properties of drug molecules.


Subject(s)
Estrogen Antagonists/chemistry , Raloxifene Hydrochloride/chemistry , Adsorption , Drug Carriers/chemistry , Particle Size , Polyethylene Glycols/chemistry , Porosity , Solubility , Surface Properties , Thermodynamics
3.
J Chromatogr Sci ; 57(7): 644-652, 2019 Aug 01.
Article in English | MEDLINE | ID: mdl-31095672

ABSTRACT

A sensitive, selective and precise high performance thin layer chromatographic method has been developed and validated for the quantification of Brexpiprazole in bulk drug and in pharmaceutical dosage form. The method employed HPTLC aluminum plates (pre-coated with silica gel 60 F254) as stationary phase while n-butanol was used as mobile phase. The Rf value of Brexpiprazole was observed to be 0.38. The densitometric analysis was carried out in absorbance mode at 215 nm. The linear regression analysis data for the calibration plots showed a good linear relationship for Brexpiprazole over a concentration range of 200-1,600 ng band-1. The limit of detection and limit of quantification for Brexpiprazole was found to be 66 and 200 ng band-1. To find out the possible degradation pathway, forced degradation studies were performed. The stock solutions of Brexpiprazole (1,000 µg mL-1) were subjected to acid and alkali hydrolysis, chemical oxidation, dry heat degradation and photo degradation. The drug was found to be susceptible to acid and alkali hydrolysis, chemical oxidation, photo degradation and dry heat. The degraded product peaks were well resolved from the pure drug peak with significant difference in their Rf values. Stressed samples were analyzed using developed HPTLC method. The proposed method was validated with respect to linearity, accuracy, precision and robustness. The method was successfully applied to the estimation of Brexpiprazole in marketed formulation and determination of content uniformity of tablet formulation. Statistical analysis showed that the method is repeatable, selective, and precise.


Subject(s)
Chromatography, Thin Layer/methods , Densitometry/methods , Quinolones/analysis , Quinolones/chemistry , Thiophenes/analysis , Thiophenes/chemistry , Drug Stability , Limit of Detection , Linear Models , Reproducibility of Results , Tablets
4.
Curr Drug Discov Technol ; 15(4): 351-360, 2018.
Article in English | MEDLINE | ID: mdl-29065836

ABSTRACT

BACKGROUND: Aspirin combination is prescribed for its thrombolytic activity where gastric ulceration is the major side effect of aspirin which can be prevented by combining it with proton pump inhibitor omeprazole. Present study describes development of analytical method for the estimation of aspirin and omeprazole in combination. OBJECTIVE: The aim of the present study was to develop and validate chromatographic method for simultaneous analysis of aspirin and omeprazole. METHODS: Isocratic, reversed phase stability indicating liquid chromatographic method was developed for the simultaneous determination of Aspirin and Omeprazole in combination. The separation was achieved on a Thermo Scientific Hypersil ODS (250 x 4.6 mm, 5 µm) column, kept at ambient temperature, using acetonitrile: methanol: 0.05 M phosphate buffer (40:5:55; pH 4 adjusted with 0.1% tri ethyl amine) as a mobile phase at a flow rate of 1 mL/min and UV detection was performed at 225 nm. RESULTS: The retention time was found to be 3.9 min for aspirin and 5.3 min for omeprazole. The method was observed to be linear in the range of 2 - 80 µg/mL for aspirin and 1 - 40 µg/mL for omeprazole, respectively. The proposed method was validated as per ICH guidelines Q2 (R1). The developed RP- HPLC method was successfully applied for the simultaneous estimation of aspirin and omeprazole in the presence of degradation products of both the drugs. CONCLUSION: The present study describes liquid chromatographic method for the estimation of aspirin and omeprzole in combination. The method can be used for the analysis of stability samples and routine quality control samples.


Subject(s)
Aspirin/analysis , Drug Compounding/standards , Fibrinolytic Agents/analysis , Omeprazole/analysis , Aspirin/adverse effects , Aspirin/chemistry , Chemistry, Pharmaceutical/methods , Chromatography, High Pressure Liquid/methods , Drug Combinations , Drug Stability , Feasibility Studies , Fibrinolytic Agents/adverse effects , Fibrinolytic Agents/chemistry , Humans , Omeprazole/chemistry , Quality Control , Stomach Ulcer/chemically induced , Stomach Ulcer/prevention & control , Thrombosis/drug therapy
5.
J Chromatogr Sci ; 53(2): 219-25, 2015 Feb.
Article in English | MEDLINE | ID: mdl-24833347

ABSTRACT

A new rapid, selective and sensitive liquid chromatography-tandem mass spectrometric method was developed and validated for the determination of ciprofibrate, an antihyperlipidemic agent, in K2EDTA human plasma. Furosemide was used as internal standard (IS). The ciprofibrate and IS were extracted using Oasis HLB 1 cc 30 mg solid-phase extraction cartridge. The chromatographic separation was performed on ACE C18, 50 × 4.6 mm, 5 µm column. The mobile phase consisted of 0.001% ammonia in methanol-acetonitrile-water (70:20:10, v/v/v). Detection and quantitation were performed by a triple quadrupole equipped with electrospray ionization and multiple reaction monitoring in negative ionization mode. The most intense [M-H](-) transition for ciprofibrate at m/z 287.0 → 85.0 and for IS at m/z 328.9.0 → 204.9 were used for quantification. The method was found to linear over the range of 25-30,000 ng/mL (r > 0.998). The lower limit of quantitation (LLOQ) was 25 ng/mL. The extraction recovery was above 90%. The accuracy was found to be 101.26-106.44%. The stability testing was also investigated and it was found that both drug and IS were quite stable. The developed method was successfully applied to the bioequivalence study of ciprofibrate 100 mg tablet after oral administration to healthy human volunteers.


Subject(s)
Chromatography, Liquid/methods , Fibric Acids/blood , Tandem Mass Spectrometry/methods , Drug Stability , Fibric Acids/chemistry , Fibric Acids/pharmacokinetics , Humans , Limit of Detection , Linear Models , Reproducibility of Results
6.
Sci Pharm ; 80(2): 407-17, 2012.
Article in English | MEDLINE | ID: mdl-22896826

ABSTRACT

A simple, specific and stability-indicating reversed phase high performance liquid chromatographic method was developed for the quantitative determination of asenapine in tablet dosage form. A SunFire C(18), 5 µm column having 250×4.6 mm i.d. in isocratic mode, with mobile phase containing 0.02 M potassium dihydrogen phosphate: acetonitrile (95:05, v/v, pH 3.5 adjusted with 1% o-phosphoric acid) was used. The flow rate was 1.0 mL min(-1) and effluents were monitored at 232 nm. The retention time of asenapine was 5.51 min. The linearity for asenapine was in the range of 0.1-20 µg/ml. The recoveries obtained for asenapine were 98.31-101.51%. Asenapine stock solutions were subjected to acid and alkali hydrolysis, chemical oxidation, sunlight and dry heat degradation. The degraded product peaks were well resolved from the pure drug peak with significant difference in their retention time values. Stressed samples were assayed using developed LC method. The proposed method was validated with respect to linearity, accuracy, precision and robustness. The method was successfully applied to the estimation of asenapine in tablet dosage form.

7.
Sci Pharm ; 79(1): 113-22, 2011.
Article in English | MEDLINE | ID: mdl-21617776

ABSTRACT

A simple, specific and stability indicating reversed phase high performance liquid chromatographic method was developed for the simultaneous determination of paracetamol and lornoxicam in tablet dosage form. A Brownlee C-18, 5 µm column having 250×4.6 mm i.d. in isocratic mode, with mobile phase containing 0.05 M potassium dihydrogen phosphate:methanol (40:60, v/v) was used. The flow rate was 1.0 ml/min and effluents were monitored at 266 nm. The retention times of paracetamol and lornoxicam were 2.7 min and 5.1 min, respectively. The linearity for paracetamol and lornoxicam were in the range of 5-200 µg/ml and 0.08-20 µg/ml, respectively. Paracetamol and lornoxicam stock solutions were subjected to acid and alkali hydrolysis, chemical oxidation and dry heat degradation. The proposed method was validated and successfully applied to the estimation of paracetamol and lornoxicam in combined tablet dosage form.

8.
Sci Pharm ; 78(4): 857-68, 2010.
Article in English | MEDLINE | ID: mdl-21179321

ABSTRACT

The objective of the present work was to develop a stability-indicating RP-HPLC method for duloxetine hydrochloride (DUL) in the presence of its degradation products generated from forced decomposition studies. The drug substance was found to be susceptible to stress conditions of acid hydrolysis. The drug was found to be stable to dry heat, photodegradation, oxidation and basic condition attempted. Successful separation of the drug from the degradation products formed under acidic stress conditions was achieved on a Hypersil C-18 column (250 mm à 4.6 mm id, 5Îm particle size) using acetonitrile: 0.01 M potassium dihydrogen phosphate buffer (pH 5.4 adjusted with orthophosphoric acid) (50:50, v/v) as the mobile phase at a flow rate of 1.0 ml/min. Quantification was achieved with photodiode array detection at 229 nm over the concentration range 1â25 Îg/ml with range of recovery 99.8â101.3 % for DUL by the RP-HPLC method. Statistical analysis proved the method to be repeatable, specific, and accurate for estimation of DUL. It can be used as a stability-indicating method due to its effective separation of the drug from its degradation products.

9.
Cell Cycle ; 8(16): 2631-42, 2009 Aug 15.
Article in English | MEDLINE | ID: mdl-19633418

ABSTRACT

The function of the relatively well-studied DNA replication origins in the yeast Saccharomyces cerevisiae is dependent upon interactions between origin replication complex (ORC) proteins and several defined origin sequence elements, including the 11 bp ARS consensus sequence (ACS). Although the ORC proteins, as well as numerous other protein components required for DNA replication initiation, are largely conserved between yeast and mammals, DNA sequences within mammalian replication origins are highly variable and sequences homologous to the yeast ACS elements are generally not present. We have previously identified several replication initiation sites within the nontranscribed spacer region of the human ribosomal RNA gene, and found that two highly utilized sites each contain a homologue of the yeast ACS embedded within a DNA unwinding element and a matrix attachment region. Here we examine protein binding within these initiation sites, and demonstrate that these ACS homologues specifically bind the alternate splicing factor SF2/ASF as well as GAPDH in vitro, and present evidence that the SF2/ASF interaction also occurs within the nuclei of intact cells. As the moderate upregulation of SF2/ASF has been linked to oncogenesis through the promotion of alternatively spliced forms of several regulatory proteins, our results suggest an additional mechanism by which SF2/ASF may influence the transformed cell phenotype.


Subject(s)
DNA Replication/genetics , DNA, Ribosomal/genetics , Nuclear Proteins/metabolism , Replication Origin/genetics , Base Sequence , Cell Line , Chromatin Immunoprecipitation , Chromatography, Affinity , DNA, Ribosomal/chemistry , Electrophoretic Mobility Shift Assay , Humans , Molecular Sequence Data , Protein Binding , RNA-Binding Proteins , Serine-Arginine Splicing Factors
10.
J AOAC Int ; 91(5): 1075-82, 2008.
Article in English | MEDLINE | ID: mdl-18980121

ABSTRACT

Two simple and accurate methods for analysis of nebivolol hydrochloride (NEB) and hydrochlorothiazide (HCTZ) in their combined dosage forms were developed using first-order derivative spectrophotometry and reversed-phase liquid chromatography (LC). NEB and HCTZ in their combined dosage forms (tablets) were quantified using first-derivative responses at 294.6 and 334.6 nm in the spectra of their solutions in methanol. The calibration curves were linear in the concentration range of 8-40 microg/mL for NEB and 10-60 microg/mL for HCTZ. LC analysis was performed on a Phenomenex Gemini C18 column (250 x 4.6 mm id, 5 microm particle size) in the isocratic mode with 0.05 M potassium dihydrogen phosphate-acetonitrile-methanol (30 + 20 + 50, v/v/v; pH 4) mobile phase at a flow rate of 1 mL/min. Detection was made at 220 nm. Both of the drugs and the internal standard (ezetimibe) were well resolved with retention times of 5.1 min for NEB, 2.9 min for HCTZ, and 8.2 min for ezetimibe. The calibration curves were linear in the concentration range of 1-14 microg/mL for NEB and 0.3-28 microg/mL for HCTZ. Both methods were validated and found to be accurate, precise, and specific, and results were compared statistically. Developed methods were successfully applied for the estimation of NEB and HCTZ in their combined dosage forms.


Subject(s)
Antihypertensive Agents/analysis , Benzopyrans/analysis , Ethanolamines/analysis , Hydrochlorothiazide/analysis , Chromatography, High Pressure Liquid , Indicators and Reagents , Nebivolol , Reference Standards , Reproducibility of Results , Solutions , Spectrophotometry, Ultraviolet , Tablets
11.
J AOAC Int ; 88(4): 1167-72, 2005.
Article in English | MEDLINE | ID: mdl-16152937

ABSTRACT

Two simple and accurate methods of analysis to determine pioglitazone hydrochloride (PIO) and mefformin hydrochloride (MET) in combined dosage forms were developed using second-derivative spectrophotometry and reversed-phase liquid chromatography (LC). PIO and MET in combined preparations (tablets) were quantified using the second-derivative responses at 227.55 nm for PIO and 257.25 nm for MET in spectra of their solutions in a mixture of methanol and acetonitrile (30 + 70). The calibration curves were linear [correlation coefficient (r) = 0.9984 for PIO and 0.9986 for MET] in the concentration range of 8-40 microg/mL for PIO and 4-12 microg/mL for MET. In the LC method, analysis was performed on a Hypersil ODS-C18 column with 5 microm particle size using the mobile phase acetonitrile-water-acetic acid (75 + 25 + 0.3), adjusted to pH 5.5 with liquor ammonia, at a flow rate of 0.5 mL/min. Measurement was made at a wavelength of 230 nm. Both the drugs were well resolved on the stationary phase, and the retention times were 8.5 min for PIO and 16.0 min for MET. The calibration curves were linear (r = 0.9933 for PIO and 0.9958 for MET) in the concentration range of 4-20 microg/mL for PIO and MET. Both methods were validated, and the results were compared statistically. They were found to be accurate, precise, and specific. The methods were successfully applied to the estimation of PIO and MET in combined tablet formulations.


Subject(s)
Chemistry, Pharmaceutical/methods , Chromatography, Liquid/methods , Mass Spectrometry/methods , Metformin/analysis , Technology, Pharmaceutical/methods , Thiazolidinediones/analysis , Acetonitriles/analysis , Calibration , Chemistry, Pharmaceutical/instrumentation , Chromatography , Dosage Forms , Hypoglycemic Agents/analysis , Methanol/analysis , Pioglitazone , Reproducibility of Results , Spectrophotometry , Tablets , Technology, Pharmaceutical/instrumentation , Time Factors , Water
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