Multivariate guard-bands and total risk assessment on multiparameter evaluations with correlated and uncorrelated measured values

Abstract The quality, efficacy, and safety of medicines are usually verified by analytical results. Measurement uncertainty is a critical aspect for the reliability of these analytical results. The pharmacopeial compendia usually adopt a simple acceptance rule that does not consider information from measurement uncertainty. In this work, we compared decision-making using simple acceptance and decision rules with the use of guard-band for multiparameter evaluation of ofloxacin ophthalmic solution and acyclovir topical cream. Ciprofloxacin ophthalmic solution and acyclovir topical cream samples were subject to pharmacopeial tests and assays. Multivariate guard-band widths were calculated by multiplying the standard uncertainty (u) by an appropriate multivariate coverage factor (k'). The multivariate coverage factor (k') was obtained by the Monte Carlo method. According to the simple acceptance rule, all the results obtained for ciprofloxacin ophthalmic solution and acyclovir topical cream are within the specification limits. However, the risk of false conformity decisions increases for ciprofloxacin tests. Decisions made using the simple acceptance rule and decision rules with the use of guard-band may differ. The simple acceptance rule may increase the risk of false conformity decisions when the measured value is close to the regulatory specification limits and/or when the measurement uncertainty value is inappropriately high. Nevertheless, the guard-band decision rule will always reduce the risk of false conformity decisions. Therefore, using information on measurement uncertainty in conformity assessment is highly recommended to ensure the proper efficacy, safety, and quality of medicines.

Risk of false conformity decisions due to measurement uncertainty of Active Pharmaceutical Ingredient: A multiparametric evaluation

Abstract Medicines must be subject to physical, chemical, and biological analysis to guarantee their quality, safety, and effectiveness. Despite the efforts to ensure the reliability of analytical results, some uncertainty will always be associated with the measured value, which can lead to false decisions regarding conformity/non-conformity assessment. This work aims to calculate the specific risk of false decisions regarding conformity/non-conformity of acetaminophen oral solution dosage form. The acetaminophen samples from five different manufacturers (A, B, C, D, and E) were subject to an active pharmaceutical ingredient assay, density test, and dose per drop test according to the official compendia. Based on measured values and their respective uncertainties, the risk values were calculated using the Monte Carlo method implemented in an MS Excel spreadsheet. The results for two acetaminophen oral solution samples (C and D) provided an increased total risk value of false acceptance (33.1% and 9.6% for C and D, respectively). On the other hand, the results for the other three acetaminophen samples (A, B, and E) provided a negligible risk of false acceptance (0.004%, 0.025%, and 0.045% for A, B, and E, respectively). This indicates that measurement uncertainty is very relevant when a conformity assessment is carried out, and information on the risks of false decisions is essential to ensure proper decisions.

Rational drug repurposing for alzheimer's treatment using in-silico ligand and structure-based approaches

Abstract Alzheimer's disease is a devastating neurodegenerative disorder characterized by memory loss and cognitive decline. New AD treatments are essential, and drug repositioning is a promising approach. In this study, we combined ligand-based and structure-based approaches to identify potential candidates among FDA-approved drugs for AD treatment. We used the human acetylcholinesterase receptor structure (PDB ID: 4EY7) and applied Rapid Overlay of Chemical Structures and Swiss Similarity for ligand-based screening.Computational shape-based screening revealed 20 out of 760 FDA approved drugs with promising structural similarity to Donepezil, an AD treatment AChE inhibitor and query molecule. The screened hits were further analyzed using docking analysis with Autodock Vina and Schrodinger glide. Predicted binding affinities of hits to AChE receptor guided prioritization of potential drug candidates. Doxazosin, Oxypertine, Cyclopenthiazide, Mestranol, and Terazosin exhibited favorable properties in shape similarity, docking energy, and molecular dynamics stability.Molecular dynamics simulations confirmed the stability of the complexes over 100 ns. Binding free energy analysis using MM-GBSA indicated favourable binding energies for the selected drugs. ADME, formulation studies offered insights into therapeutic applications and predicted toxicity.This comprehensive computational approach identified potential FDA-approved drugs (especially Doxazosin) as candidates for repurposing in AD treatment, warranting further investigation and clinical assessment.

Estudo estrutural e comparativo entre Sirtuínas 2 de diferentes espécies de Leishmania / Structural and comparative study between Sirtuins 2 of different species of Leishmania by means of Comparative Modeling and Molecular Dynamic

As leishmanioses são doenças negligenciadas que afetam mais de um bilhão e meio de pessoas ao redor do mundo, principalmente nos países em desenvolvimento, provocando grandes impactos socioeconômicos. Os fármacos disponíveis para o tratamento dessas doenças são ineficazes e apresentam graves efeitos adversos. O processo de pesquisa de novos fármacos envolve, entre outras coisas, a seleção de alvos bioquímicos essenciais para a sobrevivência e desenvolvimento do agente causador. Neste sentido, a Sirtuína 2, uma enzima epigenética com atividade hidrolase essencial para a sobrevivência dos parasitas do gênero Leishmania se apresenta como um alvo validado na busca de novos fármacos contra essas parasitoses. O planejamento de fármacos baseado na estrutura do receptor requer o conhecimento da estrutura tridimensional da proteína alvo. Desta forma, a elucidação estrutural e um estudo minucioso das Sirtuínas das várias espécies do gênero Leishmania apresenta-se como uma importante abordagem na aplicação desta estratégia na busca por agentes quimioterápicos. Até o momento, na família Trypanosomatidae, a única estrutura tridimensional resolvida experimentalmente de uma enzima Sirtuína 2 é a da espécie L. infantum. Assim, este trabalho aplicou a abordagem de Modelagem Comparativa utilizando o software Modeller na construção de modelos da Sir2rp1 das espécies L. infantum, L. major e L. braziliensis, cujas sequências de aminoácidos foram extraídas do banco de dados UNIProt. Os modelos construídos foram validados por meio da função de escore DOPE do Modeller e dos servidores PROCHECK, MolProbity e QMEAN, avaliando sua qualidade estereoquímica e seu enovelamento. Os ligantes naturais da enzima foram sobrepostos nos modelos construídos por alinhamento estrutural utilizando o software PyMol e os complexos validados foram submetidos a simulações de Dinâmica Molecular através do pacote GROMACS. Os complexos refinados foram então analisados por meio dos softwares PyMol e LigPlotPlus e dos pacotes GROMACS e gmx_MMPBSA, e foram estudados os sítios de ligação dos substratos e os resíduos de aminoácidos relevantes envolvidos em sua ligação e reconhecimento. A Modelagem Comparativa da Sirtuína 2 humana e seus homólogos das espécies L. infantum, L. major e L. braziliensis, as simulações de Dinâmica Molecular realizadas com os modelos enzimáticos construídos e validados complexados com seus ligantes naturais, os cálculos de energia de interação entre os modelos e seus substratos e o estudo estrutural comparativo realizado entre eles nos fornecem uma base teórica para a busca de novos inibidores da Sirtuína 2 que sejam mais seletivos e potentes contra as enzimas parasitárias, abrindo caminho para o desenvolvimento de candidatos a fármacos leishmanicidas mais seguros e eficazes

Leishmaniasis are neglected diseases that affect more than one and a half billion people around the world, mainly in developing countries, causing major socioeconomic impacts. The drugs available for the treatment of these diseases are ineffective and have serious adverse effects. The process of researching new drugs involves, among other things, the selection of biochemical targets essential for the survival and development of the causative agent. In this sense, Sirtuin 2, an epigenetic enzyme with hydrolase activity essential for the survival of parasites of the Leishmania genus, presents itself as a validated target in the search for new drugs against these parasites. Structure-Based Drug Design requires knowledge of the three-dimensional structure of the target protein. In this way, structural elucidation and a detailed study of Sirtuins from various species of the genus Leishmania presents itself as an important approach in the application of this strategy in the search for chemotherapeutic agents. To date, in the Trypanosomatidae family, the only experimentally resolved three-dimensional structure of a Sirtuin 2 enzyme is that of the species L. infantum. Thus, this work applied the Comparative Modeling approach using the Modeller software in the construction of Sir2rp1 models of the species L. infantum, L. major and L. braziliensis, whose amino acid sequences were retrieved from the UNIProt database. The constructed models were validated using Modeller's DOPE score function and the PROCHECK, MolProbity and QMEAN servers, evaluating their stereochemical quality and folding. The enzyme's natural ligands were superimposed on the built models by structural alignment using the PyMol software and the validated complexes were subjected to Molecular Dynamics simulations using the GROMACS package. The refined complexes were then analyzed using the PyMol and LigPlotPlus softwares and the GROMACS and gmx_MMPBSA packages, and the substrate binding sites and relevant amino acid residues involved in their binding and recognition were studied. The Comparative Modeling of human Sirtuin 2 and its homologues from the species L. infantum, L. major and L. braziliensis, the Molecular Dynamics simulations carried out with the constructed and validated enzymatic models complexed with their natural ligands, the interaction energy calculations between the models and their substrates and the comparative structural study carried out between them provide us with a theoretical basis for the search for new Sirtuin 2 inhibitors that are more selective and potent against the parasitic enzymes, paving the way for the development of safer and more effective leishmanicidal drug candidates

Development, physicochemical evaluation, and in vivo permeation studies of topical formulations containing 0.1% tacrolimus

Abstract The objective of this paper was to develop and evaluate two semi-solid pharmaceutical forms containing 0.1% tacrolimus: cream (CRT01) and gel (GLT01). For the evaluation of physicochemical stability, at times 0, 30, 60 and 90 days, at 23°C and at 40°C, High Performance Liquid Chromatography coupled with a Diode Array Detector (HPLC-DAD) was employed. This method was developed and validated for tacrolimus quantification. The occlusivity test and skin permeation assay were also performed, using an animal model (Wistar rats), and the CRT01 and GLT01 were compared to the 0.1% tacrolimus ointment (PFU01) obtained from the University Pharmacy, Federal University of Rio de Janeiro, Brazil. CRT01 and GLT01 presented a homogeneous aspect and consistency adequate for topical products, along with sensory characteristics above PFU01. They also presented adequate physicochemical stability for 90 days and a lower occlusive effect than PFU01 (p<0.05). CRT01 showed greater affinity for the skin when compared to PFU01 and GLT01, with low systemic absorption. The CRT01 semi-solid formulation was considered the most adequate one to treat patients with atopic dermatitis or other dermatologic inflammatory diseases, promoting rational use of tacrolimus

Continuous flow Aza-Michael reaction for preparing the fast-acting synthetic opioid drug Remifentanil

Abstract Remifentanil is a modern fentanyl analogue with ultrashort-action granted by an esterase-labile methyl propanoate chain. Here, we present the development of a continuous flow methodology for the key N-alkylation step of remifentanil preparation in a biphasic, "slug-flow" regime. We screened parameters under microwave-assisted reactions, translated conditions to flow settings, and obtained remifentanil under 15-min residence time in a 1-mL microreactor, with a space-time yield of 89 mg/mL·h and 94% yield.

Encapsulation of benznidazole in nanostructured lipid carriers and increased trypanocidal activity in a resistant Trypanosoma cruzi strain

Abstract Chagas disease is a neglected parasitic disease caused by Trypanosoma cruzi, whose treatment has remained unsatisfactory for over 50 years, given that it is limited to two drugs. Benznidazole (BZN) is an efficient antichagasic drug used as the first choice, although its poor water-solubility, irregular oral absorption, low efficacy in the chronic phase, and various associated adverse effects are limiting factors for treatment. Incorporating drugs with such characteristics into nanostructured lipid carriers (NLC) is a promising alternative to overcome these limiting obstacles, enhancing drug efficacy and bioavailability while reducing toxicity. Therefore, this study proposed NLC-BZN formulations in different compositions prepared by hot-melt homogenization followed by ultrasound, and the optimized formulation was characterized by FTIR, DRX, DSC, and thermogravimetry. Biological activities included in vitro membrane toxicity (red blood cells), fibroblast cell cytotoxicity, and trypanocidal activity against epimastigotes of the Colombian strain of T. cruzi. The optimized NLC-BZN had a small size (110 nm), negative zeta potential (-18.0 mV), and high encapsulation (1.64% of drug loading), as shown by infrared spectroscopy, X-ray diffraction, and thermal analysis. The NLC-BZN also promoted lower in vitro membrane toxicity (<3% hemolysis), and 50% cytotoxic concentration (CC50) for NLC-BZN in L929 fibroblast cells (110.7 µg/mL) was twice the value as the free BZN (51.3 µg/mL). Our findings showed that the NLC-BZN had higher trypanocidal activity than free BZN against the epimastigotes of the resistant Colombian strain, and this novel NLC-BZN formulation proved to be a promising tool in treating Chagas disease and considered suitable for oral and parenteral administration

Ameliorating effects of ethanol extract of root bark of Salacia nitida on blood electrolyte and renal perturbations in Plasmodium berghei-infected mice

Abstract Malaria, a disease of public health concern is a known cause of kidney failure, and dependence on herbal medicines for its treatment is increasing due to the high cost of drugs. So this study is designed to evaluate the ameliorating effect of ethanol extract from Salacia nitida root bark on electrolyte and renal perturbations in Plasmodium berghei-infected mice. Thirty malariainfected mice divided into five groups of six mice each and another group of six uninfected mice were used for the study. 280, 430, and 580 mg/kg of extract were given to infected mice in groups B, C, and D, 4 mg/kg of artesunate given to group E mice, and 4 ml/kg of physiological saline given to group A and uninfected group F mice for five days. Serum Na+, K+, HCO3, Cl-, TB, urea, creatinine, BUN concentrations, and BUN/creatinine ratio were determined using standard methods. Results showed significant increases (p < 0.05) in Na+, K+, and HCO3 and decreases in Cl-, TB, urea, creatinine, BUN, and BUN/creatinine ratio in the infected treated mice in groups B - E. This study showed that ethanol extract of S. nitida root bark is efficient in the treatment of renal disorders and blood electrolyte perturbations

Rattus norvegicus infectados com Trypanosoma cruzi: efeitos clínicos do tratamento com Lycopodium clavatun e phosphorus ultradiluídos / Rattus norvegicus infected with Trypanosoma cruzi: clinical effects of treatment with highly diluted Lycopodium clavatun and phosphorus / Rattus norvegicus infectado con Trypanosoma cruzi: efectos clínicos del tratamiento con Clavatun licopodio altamente diluido y fósforo

A doença de Chagas causada pelo parasita Trypanosoma cruzi acomete milhões de pessoas no mundo e não conta com um medicamento de ação efetiva para o seu tratamento etiológico. As drogas disponíveis, o nifurtimox e o benznidazol possuem índices de cura baixos com efeitos colaterais e toxidade que dificultam a adesão dos pacientes à terapia. Este fato impulsiona a busca por alternativas de tratamento que sejam mais efetivas e menos agressivas. Sendo assim, este trabalho teve como objetivo a avaliação dos efeitos clínicos apresentados por Rattus norvergicus infectados por T. cruzi e tratados com soluções ultradiluídas de Lycopodium clavatum ou Phosphorus. O estudo envolveu 93 ratos com quarenta e cinco dias de idade infectados intraperitonealmente com 5x106 formas tripomastigotas sanguíneos da cepa Y de T. cruzi, distribuídos nos grupos: Sadio SD (n=13) - controle não infectado e não tratado, grupo CI (n=27) - controle infectado e tratado com solução hidroalccólica 7% (etanol ­ água), grupo LY diluição 1:1x1026 (n=27) - infectado e tratado com Lycopodium, grupo PH diluição 1:1x1026 (n=26) - infectado e tratado com Phosphorum. Os animais foram avaliados clinicamente através dos parâmetros peso, temperatura, consumo de água e ração, quantidade de excretas, diâmetro e comprimento intestinal, aspecto da pelagem e consistência das fezes. Este estudo mostrou que os parâmetros utilizados foram importantes para a definição clínica da infecção de Rattus novergicus, linhagem Wistar pelo T. cruzi. Mostrou que os medicamentos LY e PH apresentam efeitos benéficos na evolução da clínica dos animais tratados. A utilização de Lycopodium clavatum e Phosphorus diluídos na proporção de 1:1x1026, apresentaram efeitos diferentes. Oito e seis parâmetros de quatorze analisados mostraram efeitos positivos para LY e PH, respectivamente. Os parâmetros consumo de água e ração, quantidade de excretas, diarreia, alopecia difusa e comprimento intestinal apresentaram diferenças significativas em relação ao controle infectado mostrando que mais estudos são necessários com o uso de medicamentos ultradiluídos na infecção pelo T. cruzi.

Chagas disease caused by the parasite Trypanosoma cruzi affects millions of people worldwide and does not have an effective drug for its etiological treatment. The available drugs, nifurtimox and benznidazole, have low cure rates with side effects and toxicity that make it difficult for patients to adhere to therapy. This fact drives the search for treatment alternatives that are more effective and less aggressive. Therefore, this work aimed to evaluate the clinical effects presented by Rattus norvergicus infected by T. cruzi and treated with ultradiluted solutions of Lycopodium clavatum or Phosphorus. The study involved 93 forty five day old rats intraperitoneally infected with 5x106 blood trypomastigotes forms of the Y strain of T. cruzi, distributed in the following groups: Healthy SD (n=13) - non-infected and untreated control, CI group (n =27) - infected control and treated with 7% hydroalcoholic solution (ethanol ­ water), LY group dilution 1:1x1026 (n=27) - infected and treated with Lycopodium, PH group dilution 1:1x1026 (n=26) - infected and treated with Phosphorum. The animals were clinically evaluated through the parameters weight, temperature, water and feed consumption, amount of excreta, intestinal diameter and length, coat appearance and feces consistency. This study showed that the parameters used were important for the clinical definition of infection of Rattus novergicus, Wistar lineage by T. cruzi. It showed that LY and PH drugs have beneficial effects on the clinical evolution of treated animals. The use of Lycopodium clavatum and Phosphorus diluted in the ratio of 1:1x1026, showed different effects. Eight and six parameters out of fourteen analyzed showed positive effects for LY and PH, respectively. The parameters water and feed consumption, amount of excreta, diarrhea, diffuse alopecia and intestinal length showed significant differences in relation to the infected control, showing that more studies are needed with the use of ultradiluted drugs in T. cruzi infection.

La enfermedad de Chagas causada por el parásito Trypanosoma cruzi afecta a millones de personas en todo el mundo y no cuenta con un fármaco eficaz para su tratamiento etiológico. Los fármacos disponibles, nifurtimox y benznidazol, presentan bajas tasas de curación con efectos secundarios y toxicidad que dificultan la adherencia terapéutica de los pacientes. Este hecho impulsa la búsqueda de alternativas de tratamiento más eficaces y menos agresivas. Por lo tanto, este trabajo tuvo como objetivo evaluar los efectos clínicos presentados por Rattus norvergicus infectados por T. cruzi y tratados con soluciones ultradiluidas de Lycopodium clavatum o Fósforo. En el estudio participaron 93 ratas de cuarenta y cinco días de edad infectadas intraperitonealmente con 5x106 formas tripomastigotes sanguíneas de la cepa Y de T. cruzi, distribuidos en los siguientes grupos: SD sano (n=13) - control no infectado y no tratado, grupo CI (n =27) - control infectado y tratado con solución hidroalcohólica al 7% (etanol - agua), grupo LY dilución 1:1x1026 (n=27) - infectado y tratado con Lycopodium, grupo PH dilución 1:1x1026 (n=26) - infectado y tratado con Phosphorum. Los animales fueron evaluados clínicamente mediante los parámetros peso, temperatura, consumo de agua y pienso, cantidad de excrementos, diámetro y longitud intestinal, aspecto del pelaje y consistencia de las heces. Este estudio demostró que los parámetros utilizados eran importantes para la definición clínica de la infección de Rattus novergicus, linaje Wistar por T. cruzi. Demostró que los fármacos LY y PH tienen efectos beneficiosos en la evolución clínica de los animales tratados. El uso de Lycopodium clavatum y Phosphorus diluidos en la proporción de 1:1x1026, mostró efectos diferentes. Ocho y seis parámetros de los catorce analizados mostraron efectos positivos para LY y PH, respectivamente. Los parámetros consumo de agua y pienso, cantidad de excretas, diarrea, alopecia difusa y longitud intestinal mostraron diferencias significativas en relación al control infectado, mostrando que son necesarios más estudios con el uso de fármacos ultradiluidos en la infección por

Compounded drugs as an alternative to the therapeutical gaps of inborn errors of metabolism

Abstract Inborn errors of metabolism are rare disorders with few therapeutic options for their treatments, which can make patients suffer with complications. Therefore, compounded drugs might be a promising option given that they have the ability of meeting the patient's specific needs, (i) identification of the main drugs described in the literature; (ii) proposal of compounding systems and (iii) calculation of the budgetary addition for the inclusion of these drugs into the Brazilian Unified Health System. The research conducted a literature review and used management data as well as data obtained from official Federal District government websites. The study identified 31 drugs for the treatment of inborn errors of metabolism. Fifty eight percent (58%) (18) of the medicines had their current demand identified, which are currently unmet by the local Health System. The estimated budget for the production of compounded drugs was of R$363,16.98 per year for approximately 300 patients. This estimated cost represents a budgetary addition of only 0.17% from the total of expenditures planned for drug acquirement. There is a therapeutic gap for inborn errors of metabolism and compounding pharmacies show potential in ensuring access to medicine therapy with a low-cost investment.

Effect of Lyophilization on Stability of PEG-Protein Conjugate: A Case Study with Peginterferon alfa-2b

Abstract The purpose of the present study was to develop stable lyophilized formulation of peginterferon alfa-2b which is acquiescent to the short lyophilization process. The present study evaluates the effect of buffering components and cryoprotectant(s) on depegylation of the peginterferon alfa-2b in combination with lyophilization process. Finally, a short lyophilization process was identified which can produce a stable pharmaceutical form of peginterferon alfa-2b without any depegylation during long-term storage. Formulations were analyzed mainly for depegylation by HP-size exclusion chromatography and in-vitro antiviral activity. Residual moisture content in the lyophilized product was also used as a key indicating parameter to check its role with respect to depegylation upon storage under various temperature conditions. It was observed that the peginterferon alfa-2b when formulated in presence of cryoprotectant like sucrose requires longer lyophilization process of about 5 days, irrespective of the buffering components used, to reduce the level of residual moisture content and thereby to produce the stable formulation without depegylation. A stable formulation in presence of high concentration of lactose as a cryoprotectant was developed which can withstand stresses exerted to protein-polymer conjugate during lyophilization phases without any significant depegylation. A short lyophilization process of about 48 hours can be utilized for peginterferon alfa-2b when formulated in presence of lactose as a cryoprotectant through which a stable lyophilized formulation can be produced as against longer process required when sucrose is used a cryoprotectant, which is essential from commercial point of view as lyophilization is a costly process.

Effect of combined sedation using multiple drugs on inflammatory cytokines in patients with acute respiratory distress syndrome

Abstract he innate immune response plays an important role in the pathophysiology of acute respiratory distress syndrome (ARDS); however, no drug has been proven to be beneficial in the management of ARDS. Therefore, the aim of this study was to investigate the effects of using combined sedatives on systemic inflammatory responses in patients with ARDS. A total of 90 patients with ARDS and an intubation time of > 120 h were randomly divided into the propofol group (group P), midazolam group (group M), and combined sedation group (group U). Patients in groups P and M were sedated with propofol and midazolam, respectively, whereas patients in group U were sedated with a combination of propofol, midazolam, and dexmedetomidine. The dosage of sedatives and vasoactive drugs, duration of mechanical ventilation, and incidence of sedative adverse reactions were documented. The dosage of sedatives and vasoactive drugs, as well as the incidence of sedative adverse reactions in group U, was significantly lower than those in groups P and M. Similarly, the duration of mechanical ventilation in group U was significantly shorter than that in groups P and M. Hence, inducing sedation through a combination of multiple drugs can significantly reduce their adverse effects, improve their sedative effect, inhibit systemic inflammatory responses, and improve oxygenation in patients with ARDS

PVP solid dispersions containing Poloxamer 407 or TPGS for the improvement of ursolic acid release

Abstract Solid dispersions (SDs) of ursolic acid (UA) were developed using polyvinylpyrrolidone K30 (PVP K30) in combination with non-ionic surfactants, such as D-α-tocopherol polyethylene glycol 1000 succinate (TPGS) or poloxamer 407 (P407) with the aim of enhancing solubility and in vitro release of the UA. SDs were investigated using a 24 full factorial design, subsequently the selected formulations were characterized for water solubility, X-ray diffractometry (XRD), differential scanning calorimetry (DSC), particle diameter, scanning electron microscopy, drug content, physical-chemical stability and in vitro release profile. SDs showed higher UA water-solubility than physical mixtures (PMs), which was attributed by transition of the drug from crystalline to amorphous or molecular state in the SDs, as indicated by XRD and DSC analyses. SD1 (with P407) and SD2 (with TPGS) were chosen for further investigation because they had higher drug load. SD1 proved to be more stable than SD2, revealing that P407 contributed to ensure the stability of the UA. Furthermore, SD1 and SD2 increased UA release by diffusion and swelling-controlled transport, following the Weibull model. Thus, solid dispersions obtained with PVP k-30 and P407 proved to be advantageous to enhance aqueous solubility and stability of UA.

Egr-1 Enhances Drug Resistance of Breast Cancer Cells by MDR1 Dependence

Abstract Paclitaxel (PTX) is one of the most effective drugs used in the treatment of breast cancer. Nonetheless, the appearance of MDR1 (multidrug resistance 1) in tumor cells has become a significant hindrance for efficacious chemotherapy. In this study, we show that the expression level of Egr-1 (early growth response gene-1) in cancer tissues (from paclitaxel chemotherapy failure patients) and MCF-7/PTX cells (the breast cancer cell line that was resistant to paclitaxel) was increased. Cell proliferation assay and apoptosis assay revealed that Egr-1 could promote cell growth and inhibit apoptosis in MCF-7/PTX. Mechanistic studies indicated that Egr-1 could bind to the proximal MDR1 promoter and enhance MDR1 transcription. These findings indicate that paclitaxel induced Egr-1 accumulation and upregulated the expression of MDR1, thereby inducing the drug resistance in MCF-7/PTX. Our results suggest a novel pathway by which paclitaxel induces MDR1 expression, possibly illuminating a potential target pathway for the prevention of MDR1-mediated drug resistance.

Experimental acute anti-inflammatory activity of preparations with complexed cannabidiol in carriers

Abstract Cannabidiol (CBD) is a bioactive compound with promising anti-inflammatory results but has low aqueous solubility. Complexation of drugs with this characteristic in carriers is an alternative to improve their efficiency. This study aimed to prepare and characterize CBD complexes in different carriers, and to evaluate the anti-inflammatory effect of such preparations using an experimental model of edema induction in rat paws. The results were compared to a reference drug, ibuprofen (IBU). The carriers evaluated were beta cyclodextrin (bCD) and activated charcoal (AC). Quantification of the drugs in the complexes was determined, and different qualitative analyses were also performed. Oral treatments in single doses with CBD showed inhibitory effects similar to that of IBU, potentiating its bioactivity without significant adverse effects. CBD*bCD doses at 4.375, 8.75, 17.5, and 35 mg/kg significantly reduced the intensity of edema compared to equivalent doses of pure bioactive. In contrast, CBD*AC did not generate benefits. There was no significant inhibitory effect on myeloperoxidase activity, requiring more specific analyses to assess this parameter. The results suggest that the CBD*bCD complexation is perfectly feasible, increasing its anti-edematogenic efficacy in the experimental model used.

Mechanical properties and immunotherapeutic effects of dissolving microneedles with different drug loadings based on hyaluronic acid

Abstract Improving vaccine immunity and reducing antigen usage are major challenges in the clinical application of vaccines. Microneedles have been proven to be painless, minimally invasive, highly efficient, and have good patient compliance. Compared with traditional transdermal drug delivery, it can effectively deliver a large-molecular-weight drug into the skin, resulting in a corresponding immune response. However, few studies have examined the relationship between microneedle loading dose and immune effects. In this study, the hyaluronic acid (HA) conical and pyramidal dissolving microneedles were prepared by the two-step vacuum drying method, respectively. The model drug ovalbumin (OVA) was added to HA to prepare dissolving microneedles with different loading amounts. The mass ratios of HA to OVA were 5:1, 5:3, and 5:5. The mechanical properties of the dissolving microneedles were characterized using nanoindentation and in vitro puncture studies. The immune effects of the matrix and drug content were studied in Sprague-Dawley (SD) rats. Finally, the diffusion behavior of OVA and the binding mode of HA and OVA in the microneedles were simulated using Materials Studio and Autodocking software. The experimental results showed that the conical microneedles exhibited better mechanical properties. When the mass ratio of HA to OVA was 5:3, the immune effect can be improved by 37.01% compared to subcutaneous injection, and achieved a better immune effect with relatively fewer drugs. This conclusion is consistent with molecular simulations. This study provides theoretical and experimental support for the drug loading and efficacy of microneedles with different drug loadings

Interchangeability of medications and biopharmaceutical implication of taking drugs with fluids other than water: ibuprofen case study

Abstract The aim of this study was to compare the dissolution properties of ibuprofen solid oral dosage forms commercially available in Bosnia and Herzegovina and to estimate the influence of dissolution medium composition on the drug release. Eight products (A-H) were subjected to in vitro dissolution test using experimental conditions described in USP42-NF37. Dissolution properties of one selected product were examined in the presence of alcohol (22.2% v/v) and fruit juice (22.2% v/v). Products marked B-H complied with the pharmacopeial criteria. Dissolution profile of product B was similar with dissolution profiles of products D, E, F and G and similarity was also found between products A-D, C-G, D-G and E-F. Drug release from most of the examined preparations fitted best to the Weibull kinetic model. In the presence of alcohol in the medium, higher amount of ibuprofen was dissolved. Contrary, ibuprofen dissolved in the presence of fruit juice was significantly lower. Differences in the dissolution profiles of investigated preparations suggest that their interchangeability should be additionally considered and demonstrated with in vivo bioequivalence studies. Presence of different substances in the medium can affect dissolution properties of ibuprofen, emphasizing the importance of the patient's compliance.

Simultaneous Estimation and Validation of Four Antiepileptic Drugs from Bulk and Formulations Using Reverse Phase HPLC

Abstract Epilepsy is a disorder of the central nervous system, in which the nerve cell activity in the brain is disturbed causing seizures. The objective was to develop an RP-HPLC method for consistent simultaneous quantitation of four antiepileptic drugs Levetiracetam (LVT), Lamotrigine (LTG), Phenobarbital (PBT) and Phenytoin (PTY). An isocratic method was developed on C18 column in JASCO HPLC using 5 mM potassium phosphate buffer (pH 6) and acetonitrile as the mobile phase at a flow rate of 1ml/min and detected at 230 nm using UV detector. The mean retention time for LVT, LTG, PBT and PTY were found as 2.55, 3.55, 4.65 and 5.99 minutes respectively. The method was validated as per ICH guidelines and was found to be acceptable. The %RSD value was <2.0 % thus stating the developed method was precise for the drugs in the given range. The accuracy values were within 85-115% of the recovery range. The specificity of the method was evaluated by an assay of marketed formulation, and it showed a percent content between 90-110% w/w for all the four drugs. The proposed analytical method was simple, accurate and robust and was precisely able to resolve the four major antiepileptic drugs. Hence, the current method can be applied successfully for routine examination of these drugs

Propyl (E)-3-(furan-2-yl) Acrylate: a synthetic antifungal potential with a regulatory effect on the biosynthesis of ergosterol in Candida Albicans

Abstract The genus Candida represents the main cause of infections of fungal origin. Some species stand out as disease promoters in humans, such as C. albicans, C. glabrata, C. parapsilosis, and C. tropicalis. This study evaluated the antifungal effects of propyl (E)-3-(furan-2-yl) acrylate. The minimum inhibitory concentration of the synthetic compound, amphotericin B and fluconazole alone against four species of Candida ranged from 64 to 512 µg/mL, 1 to 2 µg/mL, and 32 to 256 µg/mL, respectively. The synergistic effect of the test substance was observed when associated with fluconazole against C. glabrata, there was no antagonism between the substances against any of the tested strains. The potential drug promoted morphological changes in C. albicans, decreasing the amount of resistance, virulence, and reproduction structures, such as the formation of pseudohyphae, blastoconidia, and chlamydospores, ensuring the antifungal potential of this substance. It was also possible to identify the fungicidal profile of the test substance through the study of the growth kinetics of C. albicans. Finally, it was observed that the test compound inhibited the ergosterol biosynthesis by yeast

Development of metformin HCl granules using brown flaxseed mucilage as a retardant polymer: effects of polymer and drug ratio

Abstract Flaxseed (Linum usitatissimum L.) is the seed of a multipurpose plant of pharmaceutical interest, as its mucilage can be used as a natural matrix to develop extended-release dosage forms and potentially replace synthetic polymers. In this study, a 3² factorial design with two replicates of the central point was applied to optimize the development of extended-release granules of metformin HCl. The total fiber content of the mucilage as well as the friability and dissolution of the formulations were evaluated. The lyophilized mucilage presented a high total fiber content (42.63%), which suggests a high efficiency extraction process. Higher concentrations of the mucilage and metformin HCl yielded less friable granules. In addition, lower concentrations of metformin HCl and higher concentrations of the mucilage resulted in slower drug release during the dissolution assays. The release kinetics for most formulations were better represented by the Hixson-Crowell model, while formulations containing a higher concentration of the mucilage were represented by the Korsmeyer-Peppas model. Nonetheless, five formulations showed a longer release than the reference HPMC formulation. More desirable results were obtained with a higher concentration of the mucilage (13-18%) and a lower concentration of metformin (40%).