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1.
Pharmaceuticals (Basel) ; 17(4)2024 Mar 25.
Article in English | MEDLINE | ID: mdl-38675376

ABSTRACT

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.

2.
J Ultrasound ; 26(4): 793-797, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37540347

ABSTRACT

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.


Subject(s)
Muscular Diseases , Humans , Follow-Up Studies , Muscular Diseases/diagnostic imaging , Biopsy, Fine-Needle , Muscles , Image-Guided Biopsy/adverse effects , Ultrasonography, Interventional/adverse effects , Retrospective Studies
3.
Eur J Pharm Biopharm ; 183: 74-91, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36623752

ABSTRACT

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.


Subject(s)
Amphotericin B , Mycoses , Male , Mice , Animals , Amphotericin B/pharmacology , Amphotericin B/chemistry , Antifungal Agents/chemistry , Itraconazole , Mycoses/drug therapy , Candida albicans
4.
Pharmaceutics ; 14(11)2022 Oct 28.
Article in English | MEDLINE | ID: mdl-36365143

ABSTRACT

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.

5.
Pharmaceutics ; 12(11)2020 Nov 20.
Article in English | MEDLINE | ID: mdl-33233520

ABSTRACT

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.

6.
BJR Case Rep ; 6(1): 20190072, 2020 Mar.
Article in English | MEDLINE | ID: mdl-32201613

ABSTRACT

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.

7.
Eur J Pharm Biopharm ; 144: 139-153, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31536784

ABSTRACT

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.


Subject(s)
Amino Acids/chemistry , Trehalose/chemistry , Administration, Inhalation , Aerosols/chemistry , Chemistry, Pharmaceutical/methods , Drug Compounding/methods , Dry Powder Inhalers/methods , Humidity , Hydrophobic and Hydrophilic Interactions , Leucine/chemistry , Powders/chemistry , Wettability/drug effects
8.
Int J Pharm ; 551(1-2): 241-256, 2018 Nov 15.
Article in English | MEDLINE | ID: mdl-30223079

ABSTRACT

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.


Subject(s)
Drug Compounding/methods , Excipients/chemistry , Crystallization , Desiccation , Hot Temperature , Ibuprofen/chemistry , Mannitol/chemistry , Niacinamide/chemistry , Polyethylene Glycols/chemistry , Polyvinyls/chemistry , Pyrrolidines/chemistry , Xylitol/chemistry
9.
Prehosp Emerg Care ; 22(6): 784-787, 2018.
Article in English | MEDLINE | ID: mdl-29768077

ABSTRACT

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.


Subject(s)
After-Hours Care , Heart Arrest/therapy , Private Facilities , Safety , Volunteers , Adult , Cardiopulmonary Resuscitation/education , Defibrillators , Emergency Medical Services/statistics & numerical data , Female , Humans , Male , Middle Aged , Surveys and Questionnaires , Volunteers/education , Washington
10.
Eur J Pharm Biopharm ; 124: 13-27, 2018 Mar.
Article in English | MEDLINE | ID: mdl-29196273

ABSTRACT

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.


Subject(s)
Aminosalicylic Acid/chemistry , Anti-Bacterial Agents/chemistry , Sulfamethazine/chemistry , Administration, Oral , Aerosols , Aminosalicylic Acid/administration & dosage , Aminosalicylic Acid/pharmacokinetics , Animals , Anti-Bacterial Agents/administration & dosage , Anti-Bacterial Agents/pharmacokinetics , Biological Availability , Crystallization , Delayed-Action Preparations , Drug Combinations , Drug Compounding , Drug Liberation , Drug Stability , Feasibility Studies , Ibuprofen/administration & dosage , Ibuprofen/chemistry , Mice , Niacin/administration & dosage , Niacin/chemistry , Niacinamide/administration & dosage , Niacinamide/chemistry , Solubility , Staphylococcus aureus/drug effects , Staphylococcus aureus/growth & development , Sulfamethazine/administration & dosage , Sulfamethazine/pharmacokinetics , Technology, Pharmaceutical/methods
11.
Mol Pharm ; 14(11): 3718-3728, 2017 11 06.
Article in English | MEDLINE | ID: mdl-28922604

ABSTRACT

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.


Subject(s)
Antifungal Agents/chemistry , Itraconazole/chemistry , Triazoles/chemistry , Cellulose/chemistry , Tartrates/chemistry
12.
Int J Pharm ; 531(1): 191-204, 2017 Oct 05.
Article in English | MEDLINE | ID: mdl-28801109

ABSTRACT

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.


Subject(s)
Excipients/analysis , Powders/analysis , Technology, Pharmaceutical , Chemistry, Pharmaceutical , Particle Size , Tablets
13.
Eur J Pharm Sci ; 81: 181-8, 2016 Jan 01.
Article in English | MEDLINE | ID: mdl-26493586

ABSTRACT

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.


Subject(s)
Excipients/chemistry , Budesonide/chemistry , Chemistry, Pharmaceutical , Drug Compounding , Griseofulvin/chemistry , Transition Temperature
14.
Mol Pharm ; 13(1): 100-12, 2016 Jan 04.
Article in English | MEDLINE | ID: mdl-26641021

ABSTRACT

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.


Subject(s)
Anti-Bacterial Agents/pharmacology , Ciprofloxacin/pharmacology , Cell Line , Humans , Lung/microbiology , Microbial Sensitivity Tests , Microscopy, Electron, Scanning , Pseudomonas aeruginosa/drug effects , Spectroscopy, Fourier Transform Infrared , Staphylococcus aureus/drug effects , X-Ray Diffraction
15.
J Pharm Pharmacol ; 68(5): 665-77, 2016 May.
Article in English | MEDLINE | ID: mdl-26408342

ABSTRACT

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.


Subject(s)
Acedapsone/chemistry , Aminosalicylic Acid/chemistry , Anti-Infective Agents/chemistry , Acetone/chemistry , Aerosols , Crystallization , Crystallography, X-Ray , Drug Combinations , Drug Compounding , Ethanol/chemistry , Kinetics , Microscopy, Electron, Scanning , Models, Chemical , Models, Molecular , Powder Diffraction , Powders , Solubility , Solvents/chemistry , Surface Properties , Technology, Pharmaceutical/methods
16.
J Pharm Sci ; 104(4): 1385-98, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25605031

ABSTRACT

Polymorphism of crystalline drugs is a common phenomenon. However, the number of reported polymorphic cocrystals is very limited. In this work, the synthesis and solid-state characterization of a polymorphic cocrystal composed of sulfadimidine (SD) and 4-aminosalicylic acid (4-ASA) is reported for the first time. By liquid-assisted milling, the SD:4-ASA 1:1 form I cocrystal, the structure of which has been previously reported, was formed. By spray drying, a new polymorphic form (form II) of the SD:4-ASA 1:1 cocrystal was discovered which could also be obtained by solvent evaporation from ethanol and acetone. Structure determination of the form II cocrystal was calculated using high-resolution X-ray powder diffraction. The solubility of the SD:4-ASA 1:1 cocrystal was dependent on the pH and predicted by a model established for a two amphoteric component cocrystal. The form I cocrystal was found to be thermodynamically more stable in aqueous solution than form II, which showed transformation to form I. Dissolution studies revealed that the dissolution rate of SD from both cocrystals was enhanced when compared with a physical equimolar mixture and pure SD. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 104:1385-1398, 2015.


Subject(s)
Aminosalicylic Acid/chemistry , Anti-Bacterial Agents/chemistry , Anti-Inflammatory Agents/chemistry , Sulfamethazine/chemistry , Acetone/chemistry , Chemistry, Pharmaceutical , Crystallization , Crystallography, X-Ray , Drug Combinations , Drug Stability , Ethanol/chemistry , Hydrogen-Ion Concentration , Kinetics , Magnetic Resonance Spectroscopy , Models, Chemical , Models, Molecular , Powder Diffraction , Solubility , Solvents/chemistry , Spectroscopy, Fourier Transform Infrared , Technology, Pharmaceutical/methods , Temperature
17.
J Aerosol Med Pulm Drug Deliv ; 28(4): 247-53, 2015 Aug.
Article in English | MEDLINE | ID: mdl-25393346

ABSTRACT

BACKGROUND: Dry powder inhaler (DPI) users frequently exhale into their inhaler mouthpiece before the inhalation step. This error in technique compromises the integrity of the drug and results in poor bronchodilation. This study investigated the effect of four exhalation factors (exhalation flow rate, distance from mouth to inhaler, exhalation duration, and relative air humidity) on dry powder dose delivery. Given that acoustic energy can be related to the factors associated with exhalation sounds, we then aimed to develop a method of identifying and quantifying this critical inhaler technique error using acoustic based methods. METHODS: An in vitro test rig was developed to simulate this critical error. The effect of the four factors on subsequent drug delivery were investigated using multivariate regression models. In a further study we then used an acoustic monitoring device to unobtrusively record the sounds 22 asthmatic patients made whilst using a Diskus(™) DPI. Acoustic energy was employed to automatically detect and analyze exhalation events in the audio files. RESULTS: All exhalation factors had a statistically significant effect on drug delivery (p<0.05); distance from the inhaler mouthpiece had the largest effect size. Humid air exhalations were found to reduce the fine particle fraction (FPF) compared to dry air. In a dataset of 110 audio files from 22 asthmatic patients, the acoustic method detected exhalations with an accuracy of 89.1%. We were able to classify exhalations occurring 5 cm or less in the direction of the inhaler mouthpiece or recording device with a sensitivity of 72.2% and specificity of 85.7%. CONCLUSIONS: Exhaling into a DPI has a significant detrimental effect. Acoustic based methods can be employed to objectively detect and analyze exhalations during inhaler use, thus providing a method of remotely monitoring inhaler technique and providing personalized inhaler technique feedback.


Subject(s)
Acoustics , Asthma/drug therapy , Bronchodilator Agents/administration & dosage , Drug Delivery Systems/instrumentation , Dry Powder Inhalers , Exhalation , Fluticasone-Salmeterol Drug Combination/administration & dosage , Inhalation , Administration, Inhalation , Aerosols , Air , Algorithms , Asthma/physiopathology , Bronchodilator Agents/chemistry , Case-Control Studies , Equipment Design , Fluticasone-Salmeterol Drug Combination/chemistry , Humans , Humidity , Lung/drug effects , Lung/physiopathology , Multivariate Analysis , Powders , Regression Analysis , Respiratory Sounds , Signal Processing, Computer-Assisted , Sound Spectrography , Time Factors
18.
Pharm Res ; 31(10): 2735-47, 2014 Oct.
Article in English | MEDLINE | ID: mdl-24867420

ABSTRACT

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.


Subject(s)
Acoustics/instrumentation , Drug Delivery Systems/instrumentation , Dry Powder Inhalers , Inhalation/physiology , Inspiratory Capacity/physiology , Administration, Inhalation , Aerosols , Albuterol/administration & dosage , Albuterol/analogs & derivatives , Albuterol/blood , Albuterol/pharmacokinetics , Androstadienes/administration & dosage , Androstadienes/blood , Androstadienes/pharmacokinetics , Drug Combinations , Equipment Design , Fluticasone-Salmeterol Drug Combination , Humans
19.
Health Phys ; 98 Suppl 1: S17-21, 2010 Feb.
Article in English | MEDLINE | ID: mdl-20065666

ABSTRACT

On 8 June 2007, the Department of Energy amended its occupational radiation protection rule Title 10 Code of Federal Regulations Part 835, Occupational Radiation Protection. The Department of Energy revised the radiation weighting factors, tissue weighting factors, and most of the dosimetric terms used in Title 10 Code of Federal Regulations Part 835 to reflect the recommendations for assessing dose and associated terminology from ICRP Publication 60, 1990 Recommendations of the ICRP on Radiological Protection. In support of the amendment, the Department of Energy is revising its guidance documents on evaluation of radiological vs. chemical toxicity limits for varying enrichments of uranium. The revised guidance is based on the updated dosimetric models and provides a useful tool for evaluating when either radiological or chemical toxicity concerns are more limiting.


Subject(s)
Radiation Protection/standards , Uranium/isolation & purification , Uranium/toxicity , Air Pollutants, Occupational/toxicity , Air Pollutants, Radioactive/toxicity , Government Agencies , Health Physics , Humans , Occupational Exposure/standards , Occupational Exposure/statistics & numerical data , Occupational Health , Radiation Dosage , Radiation Protection/statistics & numerical data , United States
20.
Health Phys ; 97(2 Suppl): S131-5, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19590265

ABSTRACT

On 8 June 2007, the Department of Energy amended its occupational radiation protection rule Title 10 Code of Federal Regulations Part 835, Occupational Radiation Protection. Department of Energy revised the radiation weighting factors, tissue weighting factors and most of the dosimetric terms used in Title 10 Code of Federal Regulations Part 835 to reflect the recommendations for assessing dose and associated terminology from ICRP Publication 60, 1990 Recommendations of the ICRP on Radiological Protection. In support of the amendment, Department of Energy is revising its guidance documents on establishing bioassay result goals, which are used in assessing bioassay capabilities and establishing bioassay frequencies. The revised guidance is based on the updated dosimetric models and provides a useful tool for evaluating aspects of a bioassay program which may need revision.


Subject(s)
Biological Assay/methods , Plutonium/analysis , United States Government Agencies , Uranium/analysis , Biological Assay/standards , Feces/chemistry , Humans , Plutonium/urine , Radiation Dosage , Radiometry , United States , Uranium/urine
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