15 research outputs found

    Multiple novel prostate cancer susceptibility signals identified by fine-mapping of known risk loci among Europeans

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    Genome-wide association studies (GWAS) have identified numerous common prostate cancer (PrCa) susceptibility loci. We have fine-mapped 64 GWAS regions known at the conclusion of the iCOGS study using large-scale genotyping and imputation in 25 723 PrCa cases and 26 274 controls of European ancestry. We detected evidence for multiple independent signals at 16 regions, 12 of which contained additional newly identified significant associations. A single signal comprising a spectrum of correlated variation was observed at 39 regions; 35 of which are now described by a novel more significantly associated lead SNP, while the originally reported variant remained as the lead SNP only in 4 regions. We also confirmed two association signals in Europeans that had been previously reported only in East-Asian GWAS. Based on statistical evidence and linkage disequilibrium (LD) structure, we have curated and narrowed down the list of the most likely candidate causal variants for each region. Functional annotation using data from ENCODE filtered for PrCa cell lines and eQTL analysis demonstrated significant enrichment for overlap with bio-features within this set. By incorporating the novel risk variants identified here alongside the refined data for existing association signals, we estimate that these loci now explain ∼38.9% of the familial relative risk of PrCa, an 8.9% improvement over the previously reported GWAS tag SNPs. This suggests that a significant fraction of the heritability of PrCa may have been hidden during the discovery phase of GWAS, in particular due to the presence of multiple independent signals within the same regio

    Formulation Strategies To Enhance Solubility And Permeability Of Small Molecules For Drug Delivery Applications

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    All the new chemical entities/drug molecules intended for therapeutic use must be administered using an appropriate delivery system/dosage form to achieve maximum bioavailability. However, designing a drug delivery system is complex as several factors such as lipophilicity, molecular mass, crystallinity, ionic charge, polymorphic forms and hydrogen bonding) affect the solubility and permeability of these molecules. Biopharmaceutics drug classification system (BCS) categorizes the existing drugs into four classes based on the aqueous solubility and membrane permeability and it is reported that \u3e70% of the drugs are poorly soluble and belong to BCS class II and BCS class IV. Several physical, chemical and formulation techniques have been employed to improve the bioavailability. This Dissertation delineates several formulation strategies to improve the solubility and permeability of small molecules for drug delivery applications. Global incidence of superficial fungal infections caused by dermatophytes is high and affects around 40 million people. It is the fourth most common cause of infection. Clotrimazole, a broad-spectrum imidazole antifungal agent is widely used to treat fungal infections. Conventional topical formulations of clotrimazole are intended to treat infections by effective penetration of drugs into the stratum corneum. However, drawbacks such as poor dermal bioavailability, poor penetration, variable drug levels limit the efficiency. The first study was aimed to load clotrimazole into ufosomes and evaluate its topical bioavailability. Clotrimazole loaded ufosomes were prepared using cholesterol and sodium oleate by thin film hydration technique and evaluated for size, poly dispersity index (PDI), and entrapment efficiency to obtain optimized formulation. Optimized formulation was characterized using scanning electron microscopy (SEM), x-ray diffraction (XRD) and differential scanning calorimetry (DSC). Skin diffusion studies and tape-stripping were performed using human skin to determine the amount of clotrimazole accumulated in different layers of the skin. Results showed that the optimized formulation had vesicle size \u3c250 nm with\u3e~84% entrapment efficiency. XRD and DSC confirmed the entrapment of clotrimazole into ufosomes. No permeation was observed through the skin up to 24 h following the permeation studies. Tape-stripping revealed that ufosomes led to accumulation of more clotrimazole in the skin compared to marketed formulation (Perrigo). Overall, results revealed the capability of ufosomes in improving the skin bioavailability of clotrimazole. Perinatal asphyxia caused due to hypoxia complicates and causes hypoxic-ischemic encephalopathy (HIE). Therapeutic hypothermia widely used to treat HIE and is successful in 50%-60% patient population. It was reported that lutein supplementation showed neuroprotective properties in rat model of neonatal HIE. Lutein has poor bioavailability owing to poor aqueous solubility. In the second study, lutein was encapsulated into polymeric nanoparticles (PLGA and PLGA-PEG-FOLATE) and evaluated enhanced uptake in human neuroblastoma cells. Lutein loaded polymeric nanoparticles were prepared using O/W emulsion solvent-evaporation technique. Particle diameter and zeta potential (ZP) were measured using dynamic light scattering (DLS). Other characterizations included DSC, FTIR, SEM, and in vitro release studies. In vitro uptake studies were conducted in neuroblastoma cells using flow cytometry, confocal microscopy and high-performance liquid chromatography analysis. Lutein was successfully encapsulated into PLGA and PLGA-PEG-FOLATE nanoparticles with uniform size distribution of around 200 nm and high ZP. Entrapment efficiency of lutein was ~61% and ~73% for lutein PLGA and PLGA-PEG-FOLATE nanoparticles, respectively. DSC and FTIR confirmed encapsulation of lutein into nanoparticles. Cumulative release of lutein was higher in PLGA nanoparticles with 100% release within 24 hours. In PLGA-PEG-FOLATE nanoparticles, cumulative release was ~80% at 48 hours. Cellular uptake studies in neuroblastoma cells confirmed a significant increase in lutein uptake with PLGA-PEG-FOLATE nanoparticles compared to PLGA nanoparticles and lutein alone. Findings from this study suggest that lutein loaded PLGA-PEG-FOLATE nanoparticles can be potentially used for treatment of HIE. Overuse and misuse of antibiotics in clinics and poor new antibiotic pipeline in pharmaceutical industries have contributed to antibiotic crisis. Silver complexes are effective as broad-spectrum antibiotics due to chemical nature. Furosemide-silver complex (Ag-FSE) has been recently reported to have antibacterial activity that is, however, limited by its poor solubility in water and majority of organic solvents. Solid lipid nanoparticles (SLNs) offer advantages such as controlled and sustained release, enhanced solubility, scale-up and, biocompatibility. Present study aims to encapsulate Ag-FSE into SLNs and evaluate its sustained and improved antibacterial activity. Ag-FSE SLNs were prepared using hot homogenization and ultrasonication method. Size, PDI and ZP of Ag–FSE SLNs, evaluated using DLS, were 129.8±38.5 nm, 0.114 ± 0.033 and -23.9 ± 3.62 mV, respectively. Ag-FSE SLNs exhibited high encapsulation efficiency (~93%) and drug loading (~9.3%). Shape of Ag-FSE SLNs was roughly spherical with smooth surfaces. In vitro release studies confirmed that encapsulation of Ag-FSE into SLNs resulted in sustained release of Ag-FSE over 96 h. Results also confirmed 2-fold and 4-fold enhancement of activity against Pseudomonas aeruginosa and Staphylococcus aureus, respectively. In conclusion, Ag-FSE SLNs can be considered as promising topical antibacterial agent against bacterial infections

    Emergence of Nanotechnology as a Powerful Cavalry against Triple-Negative Breast Cancer (TNBC)

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    Triple-negative breast cancer (TNBC) is considered one of the un-manageable types of breast cancer, involving devoid of estrogen, progesterone, and human epidermal growth factor receptor 2 (HER 2) receptors. Due to their ability of recurrence and metastasis, the management of TNBC remains a mainstay challenge, despite the advancements in cancer therapies. Conventional chemotherapy remains the only treatment regimen against TNBC and suffers several limitations such as low bioavailability, systemic toxicity, less targetability, and multi-drug resistance. Although various targeted therapies have been introduced to manage the hardship of TNBC, they still experience certain limitations associated with the survival benefits. The current research thus aimed at developing and improving the strategies for effective therapy against TNBC. Such strategies involved the emergence of nanoparticles. Nanoparticles are designated as nanocavalries, loaded with various agents (drugs, genes, etc.) to battle the progression and metastasis of TNBC along with overcoming the limitations experienced by conventional chemotherapy and targeted therapy. This article documents the treatment regimens of TNBC along with their efficacy towards different subtypes of TNBC, and the various nanotechnologies employed to increase the therapeutic outcome of FDA-approved drug regimens

    Evaluation of Oleic Acid and Polyethylene Glycol Monomethyl Ether Conjugate (PEGylated Oleic Acid) as a Solubility Enhancer of Furosemide

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    Poor aqueous solubility limits the therapeutic efficacy of many marketed and investigational drugs. Synthesis of new drugs with improved solubility is challenging due to time constraint and expenses involved. Therefore, finding the solubility enhancers for existing drugs is an attractive and profitable strategy. In this study, PEGylated oleic acid (OA-mPEG5000), a conjugate of oleic acid and mPEG5000 was synthesized and evaluated as a solubilizer for furosemide. OA-mPEG5000 was evaluated as a nanocarrier for furosemide by formulating polymersomes. Solubility of furosemide in milli-Q water and aqueous OA-mPEG5000 solution was determined using shake flask method. At 37 °C, the solubility of furosemide in OA-mPEG5000 (1% w/w) and milli-Q water was 3404.7 ± 254.6 µg/mL and 1020.2 ± 40.9 µg/mL, respectively. Results showed there was a 3.34-fold increase in solubility of furosemide in OA-mPEG5000 compared to water at 37 °C. At 25 °C, there was a 3.31-fold increase in solubilization of furosemide in OA-mPEG5000 (1% w/w) (90.0 ± 1.45 µg/mL) compared to milli-Q water (27.2 ± 1.43 µg/mL). Size, polydispersity index and zeta potential of polymersomes ranged from 85–145.5 nm, 0.187–0.511 and −4.0–12.77 mV, respectively. In-vitro release study revealed a burst release (71%) within 1 h. Significant enhancement in solubility and formation of polymersomes suggested that OA-mPEG5000 could be a good solubilizer and nanocarrier for furosemide

    Evaluation of formulation parameters on permeation of ibuprofen from topical formulations using strat-M® membrane

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    Topical drug delivery is an attractive alternative to conventional methods because of advantages such as non-invasive delivery, by-pass of first pass metabolism, and improved patient compliance. However, several factors such as skin, physicochemical properties of the drug, and vehicle characteristics influence the permeation. Within a formulation, critical factors such as concentration of drug, physical state of drug in the formulation, and organoleptic properties affect the flux across the skin. The aim of the study was to develop and investigate topical semisolid preparations (creams and gels) with ibuprofen as the model drug and investigate the effect of various formulation parameters on the in-vitro performance across the Strat-M® membrane using flow-through cells. In addition, the physical stability of the developed formulations was investigated by studying viscosity, pH, and appearance. All the formulations developed in the study had appealing appearance with smooth texture and no signs of separation. Viscosity and pH of the formulations were acceptable. Cumulative amount of drug permeated at the end of 24 h was highest for clear gel (3% w/w ibuprofen; F6: 739.6 ± 36.1 µg/cm2) followed by cream with high concentration of ibuprofen in suspended form (5% w/w; F3: 320.8 ± 17.53 µg/cm2), emulgel (3% w/w ibuprofen; F5: 178.5 ± 34.5 µg/cm2), and cream with solubilized ibuprofen (3% w/w; F2A: 163.2 ± 9.36 µg/cm2). Results from this study showed that permeation of ibuprofen was significantly influenced by formulation parameters such as concentration of ibuprofen (3% vs. 5% w/w), physical state of ibuprofen (solubilized vs. suspended), formulation type (cream vs. gel), mucoadhesive agents, and viscosity (high vs. low). Thus, findings from this study indicate that pharmaceutical formulation scientists should explore these critical factors during the early development of any new topical drug product in order to meet pre-determined quality target product profile

    A Comprehensive Review of mRNA Vaccines

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    mRNA vaccines have been demonstrated as a powerful alternative to traditional conventional vaccines because of their high potency, safety and efficacy, capacity for rapid clinical development, and potential for rapid, low-cost manufacturing. These vaccines have progressed from being a mere curiosity to emerging as COVID-19 pandemic vaccine front-runners. The advancements in the field of nanotechnology for developing delivery vehicles for mRNA vaccines are highly significant. In this review we have summarized each and every aspect of the mRNA vaccine. The article describes the mRNA structure, its pharmacological function of immunity induction, lipid nanoparticles (LNPs), and the upstream, downstream, and formulation process of mRNA vaccine manufacturing. Additionally, mRNA vaccines in clinical trials are also described. A deep dive into the future perspectives of mRNA vaccines, such as its freeze-drying, delivery systems, and LNPs targeting antigen-presenting cells and dendritic cells, are also summarized

    A Comprehensive Review of mRNA Vaccines

    No full text
    mRNA vaccines have been demonstrated as a powerful alternative to traditional conventional vaccines because of their high potency, safety and efficacy, capacity for rapid clinical development, and potential for rapid, low-cost manufacturing. These vaccines have progressed from being a mere curiosity to emerging as COVID-19 pandemic vaccine front-runners. The advancements in the field of nanotechnology for developing delivery vehicles for mRNA vaccines are highly significant. In this review we have summarized each and every aspect of the mRNA vaccine. The article describes the mRNA structure, its pharmacological function of immunity induction, lipid nanoparticles (LNPs), and the upstream, downstream, and formulation process of mRNA vaccine manufacturing. Additionally, mRNA vaccines in clinical trials are also described. A deep dive into the future perspectives of mRNA vaccines, such as its freeze-drying, delivery systems, and LNPs targeting antigen-presenting cells and dendritic cells, are also summarized

    Recent Advances in Amorphous Solid Dispersions: Preformulation, Formulation Strategies, Technological Advancements and Characterization

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    Amorphous solid dispersions (ASDs) are among the most popular and widely studied solubility enhancement techniques. Since their inception in the early 1960s, the formulation development of ASDs has undergone tremendous progress. For instance, the method of preparing ASDs evolved from solvent-based approaches to solvent-free methods such as hot melt extrusion and Kinetisol®. The formulation approaches have advanced from employing a single polymeric carrier to multiple carriers with plasticizers to improve the stability and performance of ASDs. Major excipient manufacturers recognized the potential of ASDs and began introducing specialty excipients ideal for formulating ASDs. In addition to traditional techniques such as differential scanning calorimeter (DSC) and X-ray crystallography, recent innovations such as nano-tomography, transmission electron microscopy (TEM), atomic force microscopy (AFM), and X-ray microscopy support a better understanding of the microstructure of ASDs. The purpose of this review is to highlight the recent advancements in the field of ASDs with respect to formulation approaches, methods of preparation, and advanced characterization technique

    Preparation and Characterization of Furosemide-Silver Complex Loaded Chitosan Nanoparticles

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    Antibiotic-resistant bacteria may result in serious infections which are difficult to treat. In addition, the poor antibiotic pipeline has contributed to the crisis. Recently, a complex of furosemide and silver (Ag-FSE) has been reported as a potential antibacterial agent. However, its poor aqueous solubility is limiting its activity. The purpose of this study was to encapsulate Ag-FSE into chitosan nanoparticles (CSNPs) and evaluate antibacterial efficacy. Ag-FSE CSNPs were prepared using an ionic gelation technique. The particle size, polydispersity index, and zeta potential of Ag-FSE CSNPs were 197.1 ± 3.88 nm 0.234 ± 0.018 and 36.7 ± 1.78 mV, respectively. Encapsulation efficiency was 66.72 ± 4.14%. In vitro antibacterial activity results showed that there was 3- and 6-fold enhanced activity with Ag-FSE CSNPs against E. coli and S. aureus, respectively. Results also confirmed that Ag-FSE CSNPs showed ~44% release within 4 h at pH 5.5 and 6.5. Moreover, release from the CSNPs was sustained with a cumulative release of ~75% over a period of 24 h. In conclusion, encapsulation of Ag-FSE into CSNPs resulted in significant improvement of antibacterial efficacy with a sustained and pH-sensitive release. Therefore, Ag-FSE CSNPs can be considered as a potential novel antibacterial agent against bacterial infections

    Design and Preclinical Evaluation of Nicotine–Stearic Acid Conjugate-Loaded Solid Lipid Nanoparticles for Transdermal Delivery: A Technical Note

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    This study aimed to develop and evaluate nicotine--stearic acid conjugate-loaded solid lipid nanoparticles (NSA-SLNs) for transdermal delivery in nicotine replacement therapy (NRT). Nicotine conjugation to stearic acid prior to SLN formulation greatly increased drug loading. SLNs loaded with a nicotine–stearic acid conjugate were characterized for size, polydispersity index (PDI), zeta potential (ZP), entrapment efficiency, and morphology. Pilot in vivo testing was carried out in New Zealand Albino rabbits. The size, PDI, and ZP of nicotine–stearic acid conjugate-loaded SLNs were 113.5 ± 0.91 nm, 0.211 ± 0.01, and −48.1 ± 5.75 mV, respectively. The entrapment efficiency of nicotine–stearic acid conjugate in SLNs was 46.45 ± 1.53%. TEM images revealed that optimized nicotine–stearic acid conjugate-loaded SLNs were uniform and roughly spherical in shape. Nicotine–stearic acid conjugate-loaded SLNs showed enhanced and sustained drug levels for up to 96 h in rabbits when compared with the control nicotine formulation in 2% HPMC gel. To conclude, the reported NSA-SLNs could be further explored as an alternative for treating smoking cessation
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