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1.
Chem Res Toxicol ; 36(1): 94-103, 2023 01 16.
Artículo en Inglés | MEDLINE | ID: mdl-36602460

RESUMEN

This study used standard linear smoking machines and puffing protocols to generate data on carbonyl yields in mainstream smoke from 11 unfiltered sheet-wrapped cigars (SWC), seven leaf-wrapped cigars (LWC), and two Kentucky reference cigarettes (3R4F, 1R6F). Carbonyl yields in cigar and cigarette products were determined using three different smoking regimens: International Organization for Standardization (ISO), Canadian Intense (CI), and Cooperation Centre for Scientific Research Relative to Tobacco (CORESTA) Recommended Method (CRM) No. 64 (CRM64, Routine Analytical Cigar-Smoking Machine─Specifications, Definitions and Standard Conditions). Mainstream tobacco smoke was collected using a smoking machine fitted with an impinger containing 2,4-dinitrophenylhydrazine (DNPH) and carbonyl compounds quantified using liquid chromatography with an ultraviolet detector. Commercial SWC and LWC generated comparable formaldehyde yields (SWC, 9.4-28 µg/cigar [ISO], 8.2-43 µg/cigar [CI], 8.6-13 µg/cigar [CRM64]; LWC, 11-13 µg/cigar [ISO], 11-22 µg/cigar [CI], 16-21 µg/cigar [CRM64]) and acrolein yields; however, LWC generated higher acetaldehyde yields compared to SWC, using CI and CRM64 regimens. Reference cigarettes using standard puffing regimens generated carbonyl yields within reported ranges and 5-10% RSDs, whereas the CRM64 regimen generated lower carbonyl yields and 12-14% RSDs. Reference cigarettes generated higher formaldehyde yields using cigarette smoking regimens (21-28 µg/cigarette under ISO, 76-96 µg/cigarette under CI) but comparable formaldehyde yields under CRM64 (12-14 µg/cigarette). In addition, this study evaluated physical parameters (e.g., tobacco weight, length, diameter, circumference, tobacco rod density) that show the correlation between tobacco weight, tobacco rod density, and acetaldehyde yields under the three smoking regimens. Carbonyl yields in the mainstream smoke of cigar products using the three smoking regimens were highly variable; however, the CI smoking regimen may provide meaningful analytical information regarding cigar smoke constituents, with lower likelihood of self-extinguishment due to the short puffing intervals.


Asunto(s)
Fumar Cigarrillos , Productos de Tabaco , Canadá , Productos de Tabaco/análisis , Nicotiana/química , Formaldehído , Acetaldehído
2.
PLoS One ; 17(12): e0279309, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36538548

RESUMEN

The aerosol characteristics of electronic nicotine delivery systems (ENDS) are important parameters in predicting health outcomes since parameters such as aerosol particle size correlate strongly to aerosol delivery and deposition efficiency. However, many studies to date do not account for aerosol aging, which may affect the measurement of ultra-fine particles that typically coagulate or agglomerate during puff development. To reduce aerosol aging, we herein present a unique instrumentation method that combines a) positive pressure ENDS activation and sample collection, b) minimization of both sample tubing length and dilution factors, and c) a high-resolution, electrical low-pressure impactor. This novel approach was applied to systematically investigate the effects of coil design, coil temperature, and propylene glycol to vegetable glycerol ratios on aerosol characteristics including aerosol mass generation, aerosol count generation, and the mass and count size distributions for a high-powered ENDS. Aerosol count measurements revealed high concentrations of ultra-fine particles compared to fine and coarse particles at 200°C, while aerosol mass measurements showed an increase in the overall aerosol mass of fine and coarse particles with increases in temperature and decreases in propylene glycol content. These results provide a better understanding on how various ENDS design parameters affect aerosol characteristics and highlight the need for further research to identify the design parameters that most impact ultra-fine particle generation.


Asunto(s)
Sistemas Electrónicos de Liberación de Nicotina , Nicotina , Temperatura , Aerosoles/análisis , Propilenglicol , Material Particulado , Nebulizadores y Vaporizadores
3.
J Pharm Sci ; 111(6): 1700-1708, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-34861248

RESUMEN

Portioned moist snuff and snus, two subcategories of smokeless tobacco products (STP) were dissolution tested as a quality control test. A USP Apparatus 4 was employed to develop and validate the method. The method was assessed based on time to reach nicotine dissolution plateau, percentage difference between two profiles at each time point, relative standard deviation (RSD), and f1 (similarity) and f2 (dissimilarity) values. Based on these criteria, 200 ml volume and 8 ml/min flow were found be discriminatory. The amount of nicotine dissolved from the nine products varied widely (2.0-3.4, 2.1-4.1, 3.3-4.6, 5.5-6.6, 6.9-9.1, 11.5-14.2, 12.5-14.6, 14.0-15.5, and 15.5-19.6 mg/pouch at 60 min). RSDs of the dissolution ranges were more than 20% at earlier time points and less than 20% at later timepoints. The developed method produced distinct profiles for all the tested products, which was further confirmed by f1>15 and f2<50 values. In conclusion, the developed method was discriminatory and can be employed as a quality control test and to differentiate among moist snuff and snus products.


Asunto(s)
Tabaco sin Humo , Nicotina , Solubilidad
4.
Nicotine Tob Res ; 19(7): 865-870, 2017 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-28339569

RESUMEN

INTRODUCTION: Many carbonyls are produced from the combustion of tobacco products and many of these carbonyls are harmful or potentially harmful constituents of mainstream cigarette smoke. One carbonyl of particular interest is acrolein, which is formed from the incomplete combustion of organic matter and the most significant contributor to non-cancer respiratory effects from cigarette smoke. Sheet-wrapped cigars, also known as "little cigars," are a type of tobacco products that have not been extensively investigated in literature. METHODS: This study uses standard cigarette testing protocols to determine the acrolein yields from sheet-wrapped cigars. Sheet-wrapped cigar and cigarette products were tested by derivatizing the mainstream smoke with 2,4-dinitrophenylhydrazine (DNPH) solution and then quantifying the derivatives using conventional analytical systems. RESULTS: The results demonstrate that sheet-wrapped cigars can be tested for acrolein yields in mainstream smoke using the same methods used for the evaluation of cigarettes. The variability in the sheet-wrapped cigars and cigarettes under the International Organization for Standardization smoking regimen is statistically similar at the 95% confidence interval; however, increased variability is observed for sheet-wrapped cigar products under the Health Canada Intense (CI) smoking regimen. CONCLUSION: The amount of acrolein released by smoking sheet-wrapped cigars can be measured using standard smoking regimen currently used for cigarettes. The sheet-wrapped cigars were determined to yield similar quantity of acrolein from commercial cigarette products using two standard smoking regimens. IMPLICATIONS: This article reports on the measured quantity of acrolein from 15 commercial sheet-wrapped cigars using a validated standard smoking test method that derivatizes acrolein in the mainstream smoke with DNPH solution, and uses Liquid Chromatography/Ultra-Violet Detection (LC/UV) for separation and detection. These acrolein yields were similar to the levels found in the smoke from 35 commercial cigarette products measured in the same manner. Although sheet-wrapped cigar data were slightly more variable than those found for the cigarette data, this article reports that the production of acrolein is similar to cigarettes. The results demonstrate that sheet-wrapped cigars can be tested for acrolein yields in mainstream smoke using the same methods used for the evaluation of cigarettes.


Asunto(s)
Acroleína/análisis , Contaminantes Atmosféricos/análisis , Exposición a Riesgos Ambientales/análisis , Humo/análisis , Fumar , Productos de Tabaco/análisis , Canadá , Humanos
5.
AAPS J ; 16(4): 621-4, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24740246

RESUMEN

Principles of dissolution science have been applied to allow waiver of in vivo bioequivalence studies for oral immediate release solid dosage forms, providing certain stipulations are met. This approach reduces regulatory burden without sacrificing product quality and performance requirements that assure continuing equivalence. These principles are broadly applicable to other dosage forms and routes of administration. In this article, we postulate a further opportunity, which relies on a determination of "optimal performance" for nonsolution orally administered drug products. The determination can be applied to certain highly soluble and rapidly dissolving drug products without further study, paving the way possibly for even further reductions in regulatory burden.


Asunto(s)
Industria Farmacéutica/legislación & jurisprudencia , Industria Farmacéutica/tendencias , Equivalencia Terapéutica , Biofarmacia , Solubilidad
6.
Pharm Res ; 31(7): 1867-76, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24643933

RESUMEN

Biorelevant in vitro performance testing of orally administered dosage forms has become an important tool for the assessment of drug product in vivo behavior. An in vitro performance test which mimics the intraluminal performance of an oral dosage form is termed biorelevant. Biorelevant tests have been utilized to decrease the number of in vivo studies required during the drug development process and to mitigate the risk related to in vivo bioequivalence studies. This report reviews the ability of current in vitro performance tests to predict in vivo performance and generate successful in vitro and in vivo correlations for oral dosage forms. It also summarizes efforts to improve the predictability of biorelevant tests. The report is based on the presentations at the 2013 workshop, Biorelevant In Vitro Performance Testing of Orally Administered Dosage Forms, in Washington, DC, sponsored by the FIP Dissolution/Drug Release Focus Group in partnership with the American Association of Pharmaceutical Scientists (AAPS) and a symposium at the AAPS 2012 Annual meeting on the same topic.


Asunto(s)
Química Farmacéutica/educación , Química Farmacéutica/métodos , Evaluación Preclínica de Medicamentos/métodos , Preparaciones Farmacéuticas/administración & dosificación , Administración Oral , Química Farmacéutica/normas , Preparaciones de Acción Retardada/química , Preparaciones de Acción Retardada/metabolismo , Formas de Dosificación , Evaluación Preclínica de Medicamentos/normas , Humanos , Farmacocinética , Control de Calidad , Solubilidad
8.
Pharm Res ; 27(5): 750-5, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20217462

RESUMEN

The major metals of potential health concern found in food, drugs (medicines), and dietary supplements are lead, cadmium, mercury, and arsenic. Other metals, such as chromium, copper, manganese, molybdenum, vanadium, nickel, osmium, rhodium, ruthenium, iridium, palladium, and platinum, may be used or introduced during manufacturing and may be controlled in the final article as impurities. Screening for metals in medicines and dietary supplements rarely indicates the presence of toxic metal impurities at levels of concern. The setting of heavy metal limits is appropriate for medicines and is appropriate for supplements when heavy metals are likely or certain to contaminate a given product. Setting reasonable health-based limits for some of these metals is challenging because of their ubiquity in the environment, limitations of current analytical procedures, and other factors. Taken together, compendial tests for metals in food and drugs present an array of issues that challenge compendial scientists.


Asunto(s)
Contaminación de Medicamentos , Contaminación de Alimentos/análisis , Metales/análisis , Animales , Química Farmacéutica , Análisis de los Alimentos , Humanos , Metales/toxicidad , Farmacopeas como Asunto , Valores Limites del Umbral
9.
Vet Clin North Am Exot Anim Pract ; 9(1): 175-88, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16407085

RESUMEN

Amphibians by nature have an intimate connection with the aquatic environment at some stage of development and fight an osmotic battle due to the influx of water. Many amphibians have acquired a more terrestrial existence at later stages of development and consequently have physiologic adaptations to conserve moisture. Renal adaptations have allowed amphibians successfully to bridge the gap between aqueous and terrestrial habitats. The kidneys, skin,and, in many amphibian species, the urinary bladder play key roles in fluid homeostasis. Renal impairment may be responsible for the clinical manifestation of disease, morbidity, and mortality.


Asunto(s)
Anfibios , Enfermedades Renales/veterinaria , Riñón/anatomía & histología , Riñón/fisiología , Adaptación Fisiológica , Animales , Diagnóstico Diferencial , Riñón/patología , Enfermedades Renales/diagnóstico , Enfermedades Renales/microbiología , Enfermedades Renales/parasitología , Especificidad de la Especie
10.
Pharm Res ; 22(2): 182-7, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15783064

RESUMEN

The performance test is one of a series of tests that compose the specification in a United States Pharmacopeia (USP) dosage form monograph. For an orally administered, nonsolution dosage form, it is usually satisfied by either a dissolution or disintegration procedure. Dissolution acceptance criteria are usually set in private negotiations between an applicant and a regulatory agency. With information about this private agreement and other information provided in a sponsor's Request for Revision to USP, the USP's Council of Experts elaborates a public dosage form monograph. Based on the relationship between the regulatory decisions and the Request for Revision, the USP dissolution procedure links to a regulatory judgment about bioavailability and bioequivalence and, ultimately, to a judgment about safety and efficacy. The current dissolution procedure and acceptance criteria are perceived as having worked well over the years and are generally accepted. This article discusses new approaches that merit consideration. These approaches focus on a) explicit use of hypothesis testing, b) use of parametric tolerance intervals, c) improved ways to set dissolution acceptance criteria, and d) a more flexible protocol to assess conformity. Application of the proposed approaches may better assess, manage, and communicate both manufacturer and consumer risk for dissolution testing.


Asunto(s)
Formas de Dosificación/normas , Tecnología Farmacéutica/métodos , Administración Oral , Solubilidad , Tecnología Farmacéutica/tendencias
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