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1.
Pharmaceutics ; 14(5)2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35631620

RESUMO

The management of retinoblastoma (RB) involves the use of invasive treatment regimens. Paclitaxel (PTX), an effective antineoplastic compound used in the treatment of a wide range of malignant tumors, poses treatment challenges due to systemic toxicity, rapid elimination, and development of resistance. The goal of this work was to develop PTX-loaded, α-tocopherol succinate (αTS)-based, nanostructured lipid carrier (NLCs; αTS-PTX-NLC) and PEGylated αTS-PTX-NLC (αTS-PTX-PEG-NLC) to improve ocular bioavailability. The hot homogenization method was used to prepare the NLCs, and repeated measures ANOVA analysis was used for formulation optimization. αTS-PTX-NLC and αTS-PTX-PEG-NLC had a mean particle size, polydispersity index and zeta potential of 186.2 ± 3.9 nm, 0.17 ± 0.03, −33.2 ± 1.3 mV and 96.2 ± 3.9 nm, 0.27 ± 0.03, −39.15 ± 3.2 mV, respectively. The assay and entrapment efficiency of both formulations was >95.0%. The NLC exhibited a spherical shape, as seen from TEM images. Sterilized (autoclaved) formulations were stable for up to 60 days (last time point checked) under refrigerated conditions. PTX-NLC formulations exhibited an initial burst release and 40% drug release, overall, in 48 h. The formulations exhibited desirable physicochemical properties and could lead to an effective therapeutic option in the management of RB.

2.
Animals (Basel) ; 12(6)2022 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-35327090

RESUMO

Dairy cattle with a high milk yield are susceptible to many infectious diseases, such as mastitis. Subclinical mastitis (SCM) is the most prevalent form of mastitis that predominantly affects animal health, and causes adverse effects on the quality and quantity of milk. In dairy animals, subclinical mastitis often remains undetected, as no gross changes in udder characteristics are visible. In the present study, 135 Holstein Friesian dairy animals were selected and screened as healthy (n = 25) and mastitic (n = 110) based on diagnostic tests such as the California mastitis test, pH, electrical conductivity, and somatic cell count. In this study, the somatic cell count was used as a gold-standard test in differentiating subclinical mastitis animals from healthy ones. The present study was carried out to study polymorphisms in the bovine transferrin gene in cows (with subclinical mastitis and healthy). For the early detection of resistant/or susceptible animals, a useful marker could be provided by the detection of single-nucleotide polymorphisms (SNPs) in the transferrin gene, which are often associated with mammary innate immune response. The sequencing results revealed three nucleotide substitutions: two transversions (230 A > C, 231 C > A) and one transition (294 A > G) in susceptible cows as compared to disease-free subjects. The nucleotide variations at position 230 (GAC > GCA) and 231 (GAC > GCA) were nonsynonymous, and corresponded to an amino acid change from aspartic acid to alanine; whereas at position 294 (GAA > GAG), the mutation was synonymous. In the present study, many in silico tools were taken into consideration to determine the effect of SNPs on protein structure and function. The PROVEAN tool found the amino acid substitution to be neutral and deleterious. PolyPhen-2 revealed the amino acid variations at positions 320 and 321 to most likely be damaging; and at the 341 position, the variations were benign. The I-Mutant and MUpro tools found that the protein stability decreased for nonsynonymous variations. The SIFT tool revealed the protein function was likely to be affected in nonsynonymous variations, with no change in the case of synonymous ones. Phylogenetic analysis of the bovine transferrin gene revealed a close relation of the CA allele with the Bos taurus transferrin, while the G allele was closely related to a cross of Bos indicus × Bos taurus serotransferrins, followed by the Bison bison transferrin. The least relation was shown by both alleles to Capra hircus, Ovis aries, and Bubalus bubalis.

3.
Int J Pharm ; 616: 121564, 2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-35151817

RESUMO

The current study aimed to determine the effect of inclusion of a mucoadhesive agent on the intensity and duration of intraocular pressure (IOP) lowering activity of Δ9-tetrahydrocannabinol-valine-hemisuccinate (THC-VHS) loaded in a nanoemulsion (THC-VHS-NE) formulation. THC-VHS-NE formulation with Carbopol®940NF added as a mucoadhesive agent (THC-VHS-NEC) was prepared using hot-homogenization followed by probe sonication and characterized. A comparative evaluation of the IOP lowering activity of THC-VHS-NEC, THC-VHS-NE, THC-NEC, and commercial latanoprost ophthalmic solution, was undertaken in normotensive New Zealand white rabbits. The effect of pH, surfactant concentration, and autoclave process on the IOP lowering activity of THC-VHS-NEC was also studied. The formulation demonstrated desired viscosity, physicochemical properties, and autoclave process stability. The THC-VHS-NEC formulation showed a significant (p < 0.05) improvement in the duration of IOP lowering activity, compared to THC-NEC and THC-VHS-NE. Moreover, in this model, THC-VHS-NEC was more effective than commercially available latanoprost ophthalmic formulation, in terms of both duration and intensity of IOP lowering. A change in formulation pH, surfactant concentration, or sterilization process did not impact the IOP lowering activity of THC-VHS-NEC. Overall, inclusion of a mucoadhesive agent in THC-VHS-NE formulation, significantly increased the duration of activity, and could lead to a once- or twice- a day dosing regimen.


Assuntos
Oftalmopatias , Pressão Intraocular , Animais , Anti-Hipertensivos/uso terapêutico , Dronabinol , Oftalmopatias/tratamento farmacológico , Latanoprosta , Soluções Oftálmicas , Coelhos , Valina
4.
Drug Deliv Transl Res ; 11(5): 2096-2107, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33169348

RESUMO

The use of Δ9-tetrahydrocannabinol (THC) and Δ9-tetrahydrocannabinol-valine-hemisuccinate (THC-VHS; NB1111) has recently been investigated in the management of intraocular pressure (IOP). The current study was undertaken to develop an optimized THC-VHS-loaded nanoemulsion formulation (NE; THC-VHS-NE) that could improve the drug load and duration of activity. THC-VHS-NE formulation was prepared by homogenization followed by ultrasonication. Sesame oil, Tween®80, and Poloxamer®188 were used as the oil, surfactant, and cosurfactant, respectively. Stability of the optimized THC-VHS-NE formulation was observed at 4 °C. The IOP lowering effect of the lead formulations, commercial timolol, and latanoprost ophthalmic solutions, as well as an emulsion in Tocrisolve™ (THC-VHS-TOC), was studied in New Zealand White rabbits following topical administration. The effect of surfactant concentration and sterilization process on IOP-lowering activity was also studied. THC-VHS-NE formulations (0.5, 1.0, and 2.0% w/v) showed dose dependent duration of action. The 1.0%w/v THC-VHS-NE formulation was selected for further evaluation because of its desirable physical and chemical characteristics. THC-VHS-NE formulation prepared with 2% w/v Tween®80 exhibited a higher drop in IOP than the 0.75 and 4.0% w/v of Tween®80 containing formulations. The IOP-lowering duration was, however, similar for the formulations with 0.75 and 2.0% Tween®80, while that with 4.0% Tween®80 was shorter. THC-VHS-NE formulation produced a greater drop in IOP (p < 0.05) and a longer duration of activity compared to THC-VHS-TOC, latanoprost, and timolol. The formulation could be sterilized by filtration without impacting product attributes. Overall, the optimized THC-VHS-NE formulation demonstrated a significantly better IOP reduction profile in the test model compared to the commercial ophthalmic solutions evaluated.


Assuntos
Dronabinol , Pressão Intraocular , Animais , Anti-Hipertensivos/farmacologia , Anti-Hipertensivos/uso terapêutico , Dronabinol/farmacologia , Soluções Oftálmicas , Coelhos , Esterilização , Tensoativos , Timolol , Valina
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