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The effects of glass bead size in the conical space of flow-through cells on the dissolution profiles were investigated in a USP apparatus 4. Dissolution tests of disintegrating and non-disintegrating tablets in flow-through dissolution systems were performed using semi-high precision glass beads with diameters ranging from 0.5 mm to 1.5 mm. Computational fluid dynamics (CFD) was used to evaluate the effect of shear stress from the dissolution media flow. The use of smaller glass beads in a larger cell resulted in a faster dissolution of the model formulations under certain test conditions. The effect on the dissolution was highly dependent on the size of the beads in the top layer, including those in contact with the tablets. The absence of a bead-size effect on the dissolution of an orodispersible tablet in a small cell can be explained by the floating fragments during the test. CFD analysis showed that smaller bead diameters led to greater shear stress on the tablet, which was correlated with the dissolution rate. Hence, fluid flow through the narrow gaps between the small beads generated strong local flows, causing shear stress. The size of the glass beads used in flow-through cells affects the dissolution rate of tablets by altering the shear stress on the tablets in certain cases (e.g., direct deposition of the formulation on glass beads, large cells, and very low flow rates). Thus, glass bead size must be considered for a robust dissolution test in a flow-through cell system.
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Química Farmacéutica , Vidrio , Hidrodinámica , Tamaño de la Partícula , Solubilidad , Comprimidos , Comprimidos/química , Vidrio/química , Química Farmacéutica/métodos , Liberación de FármacosRESUMEN
Background: The combination of multiple polymers is anticipated to serve as a means to diversify the physical properties and functionalities of dissolving microneedles. The mixing state of components is considered as a crucial factor in determining their suitability. Objectives: The purpose of this study was to elucidate whether thermal analysis of frozen aqueous solutions can appropriately predict the miscibility of hyaluronic acid (HA) and other polymers used for dissolving microneedles prepared by a micromolding method. Methods: Aliquots of aqueous polymer solutions were applied for thermal analysis by heating the samples from -70 °C at 5 °C/min to obtain the transition temperature of amorphous polymers and/or the crystallization/melting peaks of polymers (e.g., polyethylene glycol (PEG)). Films and dissolving microneedles were prepared by air-drying of the aqueous polymer solutions to assess the polymer miscibility in the solids. Results: The frozen aqueous single-solute HA solutions exhibited a clear Tg' (the glass transition temperature of maximally freeze-concentrated solutes) at approximately -20 °C. The combination of HA with several polymers (e.g., dextran FP40, DEAE-dextran, dextran sulfate, and gelatin) showed a single Tg' transition at temperatures that shifted according to their mass ratio, which strongly suggested the mixing of the freeze-concentrated solutes. By contrast, the observation of two Tg' transitions in a scan strongly suggested the separation of HA and polyvinylpyrrolidone (PVP) or HA and polyacrylic acid (PAA) into different freeze-concentrated phases, each of which was rich in an amorphous polymer. The combination of HA and PEG exhibited the individual physical changes of the polymers. The polymer combinations that showed phase separation in the frozen solution formed opaque films and microneedles upon their preparation by air-drying. Coacervation occurring in certain polymer combinations was also suggested as a factor contributing to the formation of cloudy films. Conclusions: Freezing aqueous polymer solutions creates a highly concentrated polymer environment that mimics the matrix of dissolving microneedles prepared through air drying. This study demonstrated that thermal analysis of the frozen solution offers insights into the mixing state of condensed polymers, which can be useful for predicting the physical properties of microneedles.
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Regulatory T cells (Tregs) are lymphocytes that play a central role in peripheral immune tolerance. Tregs are promising targets for the prevention and suppression of autoimmune diseases, allergies, and graft-versus-host disease, and treatments aimed at regulating their functions are being developed. In this study, we created a new modality consisting of a protein molecule that suppressed excessive immune responses by effectively and preferentially expanding Tregs. Recent studies reported that tumor necrosis factor receptor type 2 (TNFR2) expressed on Tregs is involved in the proliferation and activation of Tregs. Therefore, we created a functional immunocytokine, named TNFR2-ICK-Ig, consisting of a fusion protein of an anti-TNFR2 single-chain Fv (scFv) and a TNFR2 agonist TNF-α mutant protein, as a new modality that strongly enhances TNFR2 signaling. The formation of agonist-receptor multimerization (TNFR2 cluster) is effective for the induction of a strong TNFR2 signal, similar to the TNFR2 signaling mechanism exhibited by membrane-bound TNF. TNFR2-ICK-Ig improved the TNFR2 signaling activity and promoted TNFR2 cluster formation compared to a TNFR2 agonist TNF-α mutant protein that did not have an immunocytokine structure. Furthermore, the Treg expansion efficiency was enhanced. TNFR2-ICK-Ig promotes its effects via scFv, which crosslinks receptors whereas the agonists transmit stimulatory signals. Therefore, this novel molecule expands Tregs via strong TNFR2 signaling by the formation of TNFR2 clustering.
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Anticuerpos de Cadena Única , Linfocitos T Reguladores , Proteínas Portadoras/metabolismo , Proteínas Mutantes/metabolismo , Receptores Tipo II del Factor de Necrosis Tumoral/genética , Receptores Tipo II del Factor de Necrosis Tumoral/agonistas , Anticuerpos de Cadena Única/genética , Anticuerpos de Cadena Única/farmacología , Anticuerpos de Cadena Única/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Humanos , Animales , RatonesRESUMEN
The development of generic pharmaceuticals involves a bioequivalence study to ensure the therapeutic equivalence of the test formulation to the original innovative product. The formulation characteristics of generic products are expected to be maintained in the long term after approval. This study analyzed the factors contributing to the changes in the dissolution profiles of approved products during their life cycles. Cumulative data on the dissolution similarity of 1675 products of 127 ingredients tested by official laboratories in Japan were assessed according to Japanese bioequivalence guidelines with slight modifications. The products showing dissimilarities in dissolution profiles were analyzed for reporting year, therapeutic category, co-development, physical properties of the active pharmaceutical ingredient (API), and suspected reasons for dissolution change. The increase in the number of dissimilar products is related to the co-development of generic products. Although the solubility of the API was not associated with the dissolution change in the analysis of the total dissolution data, control of the API particle size is suggested to be important for drugs with poorly soluble APIs. Additionally, a risk factor for dissolution changes in the test solutions at a certain pH was the presence of acidic or basic residues. These results indicate the importance of proper development through a thorough evaluation of the formulation and process factors affecting the dissolution properties throughout the product lifecycle.
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Medicamentos Genéricos , Equivalencia Terapéutica , Solubilidad , Medicamentos Genéricos/química , JapónRESUMEN
PURPOSE: Facial nerve decompression surgery is an invasive procedure which has hitherto been the main option for patients with severe intractable Bell's palsy which is resistant to drug treatment. We have developed a new salvage treatment for such patients by using minimally invasive transcanal endoscopic ear surgery (TEES) to deliver the biological regenerative agent, basic fibroblast growth factor (bFGF), to the damaged facial nerve. MATERIALS AND METHODS: An endoscopic salvage treatment group was studied prospectively and was made up of severe intractable Bell's palsy patients who did not respond to high dose steroid treatment and had an ENoG value of 5 % or less. This surgery group was retrospectively compared to a similar control group who had received high dose steroid only. RESULTS: Complete recovery to House-Brackmann (HB) Grade I was achieved by 44.8 % of the endoscopic salvage treatment group which was significantly higher than the 21.2 % of the control group at one-year follow up. Patients with an ENoG value of 1 % to 5 % exhibited a significantly higher complete recovery rate of 71.4 % in the endoscopic salvage treatment group than the 28.6 % of the control group. In addition, no complications were observed including hearing loss. CONCLUSIONS: bFGF delivered via TEES shows considerable promise as a new salvage treatment of severe intractable Bell's palsy that is resistant to high dose steroid treatment without the risks presented by facial nerve decompression surgery.
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Parálisis de Bell , Parálisis Facial , Humanos , Parálisis de Bell/tratamiento farmacológico , Parálisis de Bell/cirugía , Factor 2 de Crecimiento de Fibroblastos/uso terapéutico , Estudios Retrospectivos , Parálisis Facial/cirugía , Esteroides/uso terapéuticoRESUMEN
The use of apex vessels may solve coning problems associated with dissolution testing. However, excessive dissolution acceleration can reduce the discriminatory power. This study aimed to clarify how different apex vessel sizes affect the dissolution behavior of cone-forming formulations. Five apex vessels with different heights, centralities, and compendial vessels were used. The paddle rotation speed at which the coning phenomenon resolved was measured using standard particles of different densities. Three model formulations-USP prednisone tablets, atorvastatin calcium hydrate tablets, and levofloxacin fine granules-were selected, and dissolution tests were conducted at 30-100 revolutions per minute (rpm). Compared to the compendial vessels, the disappearance of standard particles at the apex base at lower paddle speeds in apex vessels was observed. Standard particles tended to remain in the center of the apex vessels and disappear at rotational speeds comparable to those of the compendial vessels. Dissolution increased in an apex height-dependent manner in the model formulations, except for the atorvastatin calcium hydrate tablets at 50 rpm. For levofloxacin fine granules, dissolution was also improved by reducing the paddle agitation speed to 30 rpm in the compendial vessels. Differences in apex centrality by 3 mm did not affect the dissolution rate. Our results indicate that apex vessels with low apex heights have a mount-resolving effect, but the degree of dissolution improvement by avoiding the coning phenomenon depends on the formulation characteristics used in the dissolution tests.
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Levofloxacino , Solubilidad , Atorvastatina , ComprimidosRESUMEN
Amphipathic arginine-rich peptide, A2-17, exhibits moderate perturbation of lipid membranes and the highest cell penetration among its structural isomers. We investigated the direct cell-membrane penetration mechanism of the A2-17 peptide while focusing on structural flexibility. We designed conformationally constrained versions of A2-17, stapled (StpA2-17) and stitched (StchA2-17), whose α-helical conformations were stabilized by chemical crosslinking. Circular dichroism confirmed that StpA2-17 and StchA2-17 had higher α-helix content than A2-17 in aqueous solution. Upon liposome binding, only A2-17 exhibited a coil-to-helix transition. Confocal microscopy revealed that A2-17 had higher cell penetration efficiency than StpA2-17, whereas StchA2-17 remained on the cell membrane without cell penetration. Although the tryptophan fluorescence analysis suggested that A2-17 and its analogs had similar membrane-insertion positions between the interface and hydrophobic core, StchA2-17 exhibited a higher membrane affinity than A2-17 or StpA2-17. Atomic force microscopy demonstrated that A2-17 reduced the mechanical rigidity of liposomes to a greater extent than StpA2-17 and StchA2-17. Finally, electrophysiological analysis showed that A2-17 induced a higher charge influx through transient pores in a planer lipid bilayer than StpA2-17 and StchA2-17. These findings indicate that structural flexibility, which enables diverse conformations of A2-17, leads to a membrane perturbation mode that contributes to cell membrane penetration.
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Apolipoproteínas E , Arginina , Péptidos , Membrana Celular , Dicroismo Circular , Liposomas , Péptidos/químicaRESUMEN
Recently, TNF receptor type 2 (TNFR2) signaling was found to be involved in the proliferation and activation of regulatory T cells (Tregs), a subpopulation of lymphocytes that suppress immune responses. Tregs mediate peripheral immune tolerance, and the disruption of their functions causes autoimmune diseases or allergy. Therefore, cell expanders or regulators of Tregs that control immunosuppressive activity can be used to treat these diseases. We focused on TNFR2, which is preferentially expressed on Tregs, and created tumor necrosis factor-α (TNF-α) muteins that selectively activate TNFR2 signaling in mice and humans, termed R2agoTNF and R2-7, respectively. In this study, we attempted to optimize the structure of muteins to enhance their TNFR2 agonistic activity and stability in vivo by IgG-Fc fusion following single-chain homo-trimerization. The fusion protein, scR2agoTNF-Fc, enhanced the expansion of CD4+CD25+ Tregs and CD4+Foxp3+ Tregs and contributed to their immunosuppressive activity ex vivo and in vivo in mice. The prophylactic administration of scR2agoTNF-Fc suppressed inflammation in contact hypersensitivity and arthritis mouse models. Furthermore, scR2-7-Fc preferentially expanded Tregs in human peripheral blood mononuclear cells via TNFR2. These TNFR2 agonist-Fc fusion proteins, which have bivalent structures, are novel Treg expanders.
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Artritis , Linfocitos T Reguladores , Animales , Humanos , Ratones , Inmunosupresores , Leucocitos Mononucleares , Receptores Tipo II del Factor de Necrosis Tumoral/genética , Factor de Necrosis Tumoral alfaRESUMEN
Neonates infected with enterovirus in utero would be fulminant at birth or develop symptoms within a few days. Echovirus 11 causes life-threatening hepatic necrosis with coagulopathy and adrenal hemorrhagic necrosis. The prognosis depends on the enterovirus serotype and the absence of serotype-specific maternal antibodies at the time of delivery. We describe a fatal neonatal case of congenital echovirus 11 infection.
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BACKGROUND: Patients on long-term dialysis are prone to hemorrhagic complications, particularly uremic bleeding, but gallbladder hemorrhage is rare, even in patients on dialysis. There have been occasional reports of a Dieulafoy lesion being a cause of gastrointestinal hemorrhage, but its occurrence within the gallbladder is quite rare. This report describes a case of gallbladder hemorrhage from a Dieulafoy lesion in a patient on hemodialysis that was diagnosed early and successfully treated by laparoscopic cholecystectomy. CASE PRESENTATION: The patient was a 68-year-old woman on long-term hemodialysis with end-stage renal failure who presented with epigastralgia and back pain. There was no history of trauma or oral administration of antiplatelet or anticoagulant agents. There were no signs of an inflammatory reaction or hyperbilirubinemia. Contrast-enhanced computed tomography revealed a slightly hyperdense area in the distended gallbladder and extravasation within the gallbladder lumen but no gallstones. A severe atherosclerotic lesion was also found. She was diagnosed to have gallbladder hemorrhage and emergency laparoscopic cholecystectomy was performed. Although the postoperative course was complicated by drug fever, she was discharged on postoperative day 10 in a satisfactory condition. Histology revealed hemorrhagic ulceration with an exposed blood vessel accompanied by abnormal arteries in the submucosa. Arteriosclerosis with eccentric intimal hyperplasia in a small-sized artery was also seen. The diagnosis was gallbladder hemorrhage from a Dieulafoy lesion. CONCLUSIONS: A Dieulafoy lesion should be kept in mind as a cause of gallbladder hemorrhage in a patient with severe arteriosclerosis and a bleeding diathesis, particularly if on dialysis, and treated as early as possible.
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Government campaigns to replace off-patent brand pharmaceuticals with low cost generic products in national health insurance systems have apparently increased their production in the last two decades in Japan. The contamination of a batch of generic itraconazole tablets with the sleep inducer rilmazafone caused significant adverse events and related accidents in 2020, amidst increasing use of the generic products in healthcare. Investigations revealed many Good Manufacturing Practice (GMP) violations and other evidence of poor quality management in the manufacturing/marketing authorization holder (MAH). Urgent inspection of other MAHs found multiple cases of GMP noncompliance that resulted in temporary administrative suspension. Various quality issues, including nonconformity in stability monitoring, in these generic MAHs resulted in prolonged suspension of product shipments and shortages in medical institutions. These problems highlighted long-standing issues in quality management by MAHs and inspections by authorities, which had been neglected during rapid production expansion. This review introduces these manufacturing control and management problems and their countermeasures, and discusses the impact of habitual inadequate development processes that disregard the quality-by-design (QbD) perspective as the root cause of the issues.
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Contaminación de Medicamentos , Medicamentos Genéricos , Japón , Industria FarmacéuticaRESUMEN
Several good manufacturing practice (GMP) compliance issues and their associated quality problems that have been revealed since 2020 have led to large-scale recalls and supply suspensions of drug products in Japan. This paper provides an overview of the causes and countermeasures for supply disruptions of low-molecular-weight chemical pharmaceutical agents, focusing on quality-related issues. A recent increase in the use of generic drugs emphasized the importance of strengthening active pharmaceutical ingredient (API) supply chains and ensuring GMP compliance among drug manufacturers. In addition, increasing recalls in the drug products of certain marketing authorization holders due to storage stability problems strongly suggests the need to improve their development process considerably. Other measures to stabilize the supply of pharmaceuticals, including increasing stockpiles of APIs, were also discussed.
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Medicamentos bajo Prescripción , Comercio , Industria Farmacéutica , Medicamentos Genéricos , Japón , Preparaciones FarmacéuticasRESUMEN
INTRODUCTION: Treating diabetic nephropathy with low-density lipoprotein (LDL) apheresis reduces proteinuria and improves prognosis. However, its impact on patients' quality of life (QoL) is unclear. This study evaluated the effect of LDL apheresis on QoL in patients with diabetes, proteinuria, and hypercholesterolemia. METHODS: In this nationwide multicenter prospective study, we enrolled 40 patients with diabetes. Inclusion criteria were proteinuria (defined as an albumin/creatinine ratio ≥3 g/g), serum creatinine levels <2 mg/dL, and serum LDL ≥120 mg/dL despite drug treatment. LDL apheresis was performed 6-12 times within 12 weeks. The 36-item Short Form Health Survey (SF-36) was used to analyze QoL. RESULTS: The study enrolled 35 patients (27 men and 8 women; mean age 58.9 ± 11.9 years). A comparison of baseline SF-36 values with those at the end of the course of apheresis found an improvement in the mean physical component summary (37.9 ± 11.4 vs. 40.6 ± 10.5, p = 0.051) and a significant increase in the mean mental component summary (MCS) (49.4 ± 8.4 vs. 52.5 ± 10.9, p = 0.026). A multivariable linear regression analysis revealed a history of coronary heart disease negatively correlated with the MCS increase at the end of the course of apheresis (ß coefficient -6.935, 95% confidence interval, 13.313 to-0.556, p = 0.034). CONCLUSION: Our results suggest that LDL apheresis may improve the mental and physical QoL in patients with diabetes, proteinuria, and hypercholesterolemia.
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Eliminación de Componentes Sanguíneos , Diabetes Mellitus , Nefropatías Diabéticas , Hipercolesterolemia , Masculino , Humanos , Femenino , Persona de Mediana Edad , Anciano , Calidad de Vida , Estudios Prospectivos , Eliminación de Componentes Sanguíneos/métodos , Lipoproteínas LDL , Proteinuria/terapia , Nefropatías Diabéticas/terapia , Resultado del Tratamiento , Diabetes Mellitus/terapiaRESUMEN
The efficacy of mRNA-lipid nanoparticles (mRNA-LNPs) depends on several factors, including their size and morphology. This study presents a new technique to characterize mRNA-LNPs in an aqueous medium using atomic force microscopy (AFM). This method utilizes an anti-polyethylene glycol antibody to immobilize mRNA-LNPs onto a glass substrate without corruption, which cannot be avoided with conventional procedures using solid substrates such as mica and glass. The obtained AFM images showed spherical and bleb-like structures of mRNA-LNPs, consistent with previous observations made using cryo-transmission electron microscopy. The AFM method also revealed the predominant existence of nanoparticles with a diameter < 60 nm, which were not detectable by dynamic light scattering and nanoparticle tracking analysis. As mRNA-LNPs are usually not monodisperse, but rather polydisperse, the AFM method can provide useful complementary information about mRNA-LNPs in their development and quality assessment.
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Liposomas , Nanopartículas , Microscopía de Fuerza Atómica/métodos , ARN Mensajero/química , Liposomas/química , Nanopartículas/química , Agua/químicaRESUMEN
Laryngeal web is a rare congenital or acquired disease that results in airway stenosis. Depending on the severity of atresia, patients with laryngeal web show a wide variety of symptoms ranging from asymptomatic to life-threatening respiratory dysfunction that may require emergency tracheostomy immediately after birth. We report a neonatal case of laryngeal web with 22q11.2 deletion syndrome. Post-delivery, the infant showed dysphonia and had a ventricular septal defect with characteristic craniofacial features. The infant underwent an endoscopic incision of the web and cardiac surgery. Among patients with laryngeal web, 30% have 22q11.2 deletion syndrome. 22q11.2 deletion syndrome is the most common chromosomal microdeletion syndrome and the second most common chromosomal abnormality associated with congenital heart disease. Therefore, if an infant has laryngeal web with comorbidities such as congenital heart disease, 22q11.2 deletion syndrome should be considered in differential diagnosis.
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Particular batches of Moderna mRNA Coronavirus Disease 2019 (COVID-19) vaccine were recalled after foreign particles were found in some vaccine vials at the vaccination site in Japan in August 2021. We investigated the foreign particles at the request of the Ministry of Health, Labour and Welfare. Energy dispersive X-ray spectroscopy analysis suggested that the foreign particles found in the vials recalled from the vaccination sites were from stainless steel SUS 316L, which was in line with the findings of the root cause investigation by the manufacturer. The sizes of the observed particles ranged from <50 µm to 548 µm in the major axis. Similar foreign particles were also detected in 2 of the 5 vaccine vials of the same lot stored by the manufacturer, indicating that the foreign particles have already been administered to some people via vaccine. Observation of the vials of the same lot by digital microscope found smaller particles those were not detected by visual inspection, suggesting that more vials were affected. Contrarily, visual inspection and subvisible particulate matter test indicated no foreign particles in the vials of normal lots. Possible root cause and strategies to prevent such a deviation were discussed from technical and regulatory aspects.
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Vacuna nCoV-2019 mRNA-1273 , COVID-19 , COVID-19/epidemiología , COVID-19/prevención & control , Vacunas contra la COVID-19 , Humanos , Japón/epidemiología , Material ParticuladoRESUMEN
OBJECTIVE: Few large-scale investigations have been conducted on treatment of House-Brackmann grade VI (HB grade VI) Ramsay Hunt syndrome (RHS) patients. We compared recovery rates among patients receiving a normal-dose corticosteroid (prednisolone [PSL] 60 mg/d) or high-dose corticosteroid (PSL 200 mg/d), both with or without an antiviral agents. Recovery rates were also examined based on the order of presentation of herpetic vesicles versus facial palsy. STUDY DESIGN: Retrospective case review. SETTING: Tertiary referral center. PATIENTS: A total of 128 patients with HB grade VI RHS were treated in our department between 1995 and 2017. These patients were divided into four treatment groups based on corticosteroid dosage and use of an antiviral agent. METHODS: We assessed treatment outcomes for HB grade VI patients together with logistic regression analysis to investigate factors that can impact treatment outcomes, that is, sex, age, days to start of treatment, PSL dosage, and antiviral agent administration. RESULTS: Recovery rates were best in the high-dose corticosteroid group with an antiviral agent (71.1%) in comparison with the normal-dose corticosteroid group with an antiviral agent (60.0%) or high-dose corticosteroid alone (57.1%). Significant factors for treatment outcomes were high-dose corticosteroid administration and early initiation of treatment. A better recovery rate was also found when the herpetic vesicles appeared before facial palsy. CONCLUSION: We showed that a combination of a high-dose corticosteroid and antiviral agent produced the best outcomes for patients with HB grade VI RHS. However, our results were not statistically significant because of small sample size.
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Parálisis de Bell , Parálisis Facial , Herpes Zóster Ótico , Disinergia Cerebelosa Mioclónica , Corticoesteroides/uso terapéutico , Antivirales/uso terapéutico , Parálisis de Bell/tratamiento farmacológico , Parálisis Facial/etiología , Herpes Zóster Ótico/complicaciones , Herpes Zóster Ótico/tratamiento farmacológico , Humanos , Disinergia Cerebelosa Mioclónica/complicaciones , Prednisolona , Estudios RetrospectivosRESUMEN
This study investigated how air bubbles in media affect tablet dissolution in a flow-through cell system (USP 4) using disintegrating (USP prednisone) and non-disintegrating (USP salicylic acid) tablets. Cell hydrodynamics were studied using particle image velocimetry (PIV) and computational fluid dynamics (CFD). The PIV analysis showed periodic changes in the local flow corresponding to the discharge and suction of the pump cycles. The absence of prior deaeration induced small air bubbles in the media and lower maximum flow during the cycle, explaining the slower dissolution of the USP salicylic acid tablets. Bubbles, occurring during the USP prednisone tablets study, induced the transition of floating disintegrated particles towards the cell outlet, whereas the particles precipitated to form a white layer on the glass beads used in the study with prior deaeration. CFD analysis showed local flow variation in multiple positions of small (ID 12 mm) and large (ID 22.6 mm) cells, explaining the different rates of dissolution of prednisone tablet particles depending on their distribution. These results emphasize the importance of prior deaeration in dissolution studies using a flow-through system. Bubbles in the flow-through cell system affected tablet dissolution by reducing the area in contact with the media (wettability), lowering the maximum instantaneous flow (pressure buffering), and altering the position of disintegrated particles in the cell.