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2024 FEB 24 (NewsRx) -- By a News Reporter-Staff News Editor at Obesity, Fitness & Wellness Week -- A new study on Biotechnology - Liposomes is now available. According to [...]

2024 FEB 10 (NewsRx) -- By a News Reporter-Staff News Editor at Obesity, Fitness & Wellness Week -- Fresh data on Oncology - Brain Cancer are presented in a new [...]

• Biodegradable contraceptive implants prepared by UV irradiation molding method. • Photo-cross-linked aliphatic polycarbonates as a matrix material. • Carrier has degradation characteristic of surface erosion mechanism. • Implants with low cytotoxicity and good biocompatibility. • Formulation has stable release kinetics and good long-acting contraceptive effects. In this study, a new class of biodegradable contraceptive implants was prepared via the UV irradiation molding method, among which, progestin levonorgestrel (LNG) was used as a model drug. Photo-cross-linked aliphatic polycarbonates (APCs), namely, poly (trimethylene carbonate-co-2,2′-dimethyltrimethylene carbonate) [P(TMC-co-DTC)] elastomers, were used as the drug delivery matrix. The results obtained from the degradation experiments carried out in Sprague-Dawley (SD) rats showed that the cross-linked elastomer had the degradation characteristics of the surface erosion degradation mechanism, with no generation of acid degradation products, and excellent form-stability, which met the performance requirements of the matrix for a long-acting sustained-release delivery system. The in vitro cytotoxicity tests and histological and immunohistochemical evaluations showed good biocompatibility and biosafety of the elastomer matrix material and contraceptive implants. Subsequently, the implant formulations were screened by in vitro release experiments, and their release kinetics were explored. Finally, in the evaluation study of the in vivo anti-fertility effect, the implants exhibited excellent dimensional stability and were degraded by a surface erosion mechanism. LNG achieved a stable and sustained release in female SD rats, maintaining a long-acting contraceptive duration of up to 4 months. The contraceptive implants obtained in this study could be used to address the limitations of currently available formulations, which required secondary surgical removal and a single means of regulating drug release kinetics. Therefore, these implants could provide a new option for birth control needs and may be of significance in reducing the incidence of induced abortion and protecting female fertility. [Display omitted] [ABSTRACT FROM AUTHOR]

Gnaphalium affine is traditionally used to treat hyperuricemia and gout in China. Recently, the hypouricemic and renal protective effects of G. affine extract (GAD) have been deeply evaluated. However, little is known about the pharmacokinetics (PKs) of bioactive constituents in GAD. This study is aimed at investigating the individual and holistic pharmacokinetics of 10 bioactive components (including caffeic acid, caffeoylquinic acids, and flavonoids) in rats after single and multiple administrations of GAD. GAD is orally dosed to normal male rats at doses of 225, 450, or 900 mg/kg/day for 10 consecutive days and also orally administrated to uric acid nephropathy (UAN) rats at a dose of 900 mg/kg/day for 28 consecutive days. Integrated PKs of multiple components are calculated by area under the curve (AUC)-based weighting approach. All the components show a double-peak phenomenon in terms of their plasma concentration-time curves, suggesting that the components undergo enterohepatic circulation. The integrated AUC increases in a good dose-proportional manner with GAD dose. Compared with that in normal rats, the plasma exposure of caffeic acid and caffeoylquinic acids increases by 2.3- to 4.3-fold after 10-day chronic treatment of 900 mg/kg GAD in UAN rats. Modest drug accumulation is observed after 28-day chronic treatment. [ABSTRACT FROM AUTHOR]

The Localized Collocation Meshless Method (LCMM) is applied to the solution of a set of partial differential equations governing the diffusive transport of a dermally injected compound as described by the Compartmental Pharmacokinetic (CPK) model. This efficient and accurate numerical technique then provides the framework for the estimation of pharmacokinetic (PK) parameters by the comparison of two models, both containing information derived from experimental results, using the iterative Golden Section search algorithm. This comparison is quantified using a norm between the two solution spaces. While this method does provide an estimate of the effective-diffusion coefficient, it ultimately demonstrates that a simple, free-diffusion model is inadequate for quantifying the spatial and temporal distribution of a dermally-injected compound if elimination effects are not accounted for properly. [ABSTRACT FROM AUTHOR]

To further study the aminoalcohol-diterpenoid alkaloids (ADAs) in Fuzi (Aconiti Lateralis Radix Praeparata), a simple and sensitive UFLC-MS/MS method was established and validated for the determination of five ADAs, aconine, mesaconine, hypaconine, deoxyaconine and fuziline, in rat plasma to compare the pharmacokinetic characteristics of pure ADAs and Fuzi decoction. After precipitating protein with methanol, plasma samples were isolated at 0.5 mL/min flow rate on Waters Acquity UPLC BEH C18 column (100 mm × 2.1 mm, 1.7 µm). The mobile phase was composed of 0.1% formic acid-water and methanol with gradient elution. Mass spectrometric inspection was conducted on a 5500 UFLC-MS/MS system with an electrospray ionization source in patterns of positive ion and multiple reaction-monitoring (MRM). All calibration curves were proved to have acceptable linearity (r2 > 0.99) in linear ranges. Intra-day and inter-day precision and the accuracy met the requirements. The matrix effects of all analytes were between 85% and 115% of three concentration levels. This method has been under verification for comparative pharmacokinetic research after oral administration between aqueous extract of Fuzi and single pure ADAs. The results demonstrated that there are evident pharmacokinetic discrepancies between them, and administration in the extract form instead of pure form may contribute to higher absorption. [ABSTRACT FROM AUTHOR]

Lasiocarpine (LAS) and heliotrine (HEL) are two different ester types of toxic pyrrolizidine alkaloids (PAs): open-chain diester and monoester. However, the pharmacokinetics of these two types of PAs in rats have not been reported. In the present study, two LC-MS/MS methods for determining LAS and HEL were established and validated. The methods exhibited good linearity, accuracy, and precision and were then applied to a comparative pharmacokinetic study. After intravenous administration to male rats at 1 mg/kg, the AUC0-t values of LAS and HEL were 336 ± 26 ng/mL × h and 170 ± 5 ng/mL × h. After oral administration at 10 mg/kg, the AUC0-t of LAS was much lower than that of HEL (18.2 ± 3.8 ng/mL × h vs. 396 ± 18 ng/mL × h), while the Cmax of LAS was lower than that of HEL (51.7 ± 22.5 ng/mL × h vs. 320 ± 26 ng/mL × h). The absolute oral bioavailability of LAS was 0.5%, which was significantly lower than that of HEL (23.3%). The results revealed that the pharmacokinetic behaviors of LAS differed from that of HEL. [ABSTRACT FROM AUTHOR]

Human cytochrome P450 1B1 (CYP1B1) is an extrahepatic enzyme overexpressed in many tumors and associated with angiogenesis. Ginkgetin, isoginkgetin, sciadopitysin, and amentoflavone, the primary biflavones found in Ginkgo biloba , have excellent anti-inflammatory and anti-tumor effects. However, the effect of biflavones on CYP1B1 activities remains unknown. In this study, 7-ethoxyresorufin O-deethylation (EROD) was used to characterize the activities of CYP1 families. The impacts of four ginkgo biflavones on CYP1B1 activity and the cellular protein expression of CYP1B1 were systematically investigated. The results showed that amentoflavone with six hydroxyl substituents exhibited the most potent selective inhibitory effect on CYP1B1 activity with IC50 of 0.054 µM in four biflavones. Sciadopitysin, with three hydroxyl and three methoxy substituents, had the weakest inhibitory activity against CYP1B1. Ginkgetin and isoginkgetin, both with four hydroxyl and two methoxy substituents, showed similar inhibitory intensity towards CYP1B1 with IC50 values of 0.289 and 0.211 µM, respectively. Kinetic analysis showed that ginkgetin and amentoflavone inhibited CYP1B1 in a non-competitive mode, whereas sciadopitysin and isoginkgetin induced competitive or mixed types of inhibition. Notably, four ginkgo biflavones were also confirmed to suppress the protein expressions of CYP1B1 and AhR in MCF-7. Furthermore, molecular docking studies indicated more hydrogen bonds formed between amentoflavone and CYP1B1, which might explain the strongest inhibitory action towards CYP1B1. In summary, these findings suggested that biflavones remarkably inhibited both the activity and protein expression of CYP1B1 and the inhibitory activities enhanced with the increasing hydroxyl substitution, providing new insights into the anti-tumor potentials of biflavones. [ABSTRACT FROM AUTHOR]

Numerous skin diseases and disorders that affect different layers of the skin can be treated with topical dermal drug delivery (TDDD) systems. Topical delivery is advantageous over systemic administration due [...]

Swertia cincta , a plant of the genus Swertia in Gentianceae, has "heat-clearing" and detoxifying effects that normalize the gallbladder function in the treatment of jaundice. Although numerous studies on Swertia cincta have been performed, the absorption and pharmacokinetic behaviors remain unclear. In this study, the compounds of Swertia cincta in serum, bile, feces, and urine of rats were analyzed using a ultra-high-performance liquid chromatography-tandem mass spectrometry. A total of 9 prototype components and 48 metabolites were detected in biological samples. Furthermore, we determined the main components absorbed in the blood of Swertia cincta and established a method for simultaneously determining these components (sweroside, swertiamarin, and gentiopicroside) in positive ionization mode within 6 min. The quantitative method was successfully applied for the multiple-component pharmacokinetic study of Swertia cincta. [ABSTRACT FROM AUTHOR]

The article explores medication dosing challenges in pediatric patients with obesity. Topics discussed include definition of obesity in individuals, according to the U.S. Centers for Disease COntrol and Preevntion and the American Academy of Pediatrics, pharmacokinetic changes in obesity, and medication dosing adjustments in children and adolescents with obesity.

The article focuses on a study from Chengdu University of Traditional Chinese Medicine comparing the pharmacokinetics of anisodamine hydrobromide tablets and injection in septic acute lung injury rats. Topics include the development of a sensitive LC-MS/MS method for analyzing drug pharmacokinetics, the different absorption rates of tablets versus injections, and the conclusion that injection administration is more effective for treating septic acute lung injury.

This document provides information about a clinical trial (NCT06568614) conducted by CSPC ZhongQi Pharmaceutical Technology Co., Ltd. The trial aims to evaluate the safety and efficacy of a drug in patients with various types of tumors, including non-small cell lung cancer, gastric adenocarcinoma, esophageal cancer, bladder cancer, pancreatic cancer, mesothelioma, and others. The trial has specific inclusion and exclusion criteria, such as the presence of MTAP deletion in tumor tissue and adequate organ function. The trial is open to all genders and participants must be at least 18 years old. The document also includes administrative information about the trial, such as study ID numbers and contact information. [Extracted from the article]

This document provides information about a clinical trial for a drug called Risankizumab, which is also known as ABBV-066 or SKYRIZI. The trial aims to assess the pharmacokinetics, relative bioavailability, and tolerability of two formulations of Risankizumab in healthy adult participants. The study will involve subcutaneous administration of the drug and will evaluate various outcomes such as adverse events, serum concentration, and elimination half-life. The trial is currently not recruiting participants and is open to all genders between the ages of 18 and 60. Contact information for the study is provided by AbbVie, the organization conducting the trial. [Extracted from the article]

A recent study conducted at the University Eye Clinic in Heidelberg, Germany, examined the in vitro pharmacokinetics of bevacizumab, an antineoplastic monoclonal antibody, in silicone oil-filled eyes compared to hydrogel replacements and the porcine vitreous body. The study found significant differences in bevacizumab partitioning across different endotamponades, with the highest accumulation in the porcine vitreous body. The researchers concluded that the type of endotamponade used heavily influenced the concentration of bevacizumab in the aqueous phase, highlighting the need for further in vivo studies to explore these interactions before clinical application. This study provides valuable insights into the use of bevacizumab in retinal surgery and its interaction with different materials. [Extracted from the article]