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BACKGROUND AND OBJECTIVE: Ivermectin (IVM), a widely used veterinary anthelmintic, lacks recommended doses for Bactrian camels. This study aims to establish its pharmacokinetics in Bactrian camels, comparing with other livestock. METHODS: A method for high-performance liquid chromatography fluorescence detection of IVM in plasma was developed. RESULTS: IVM exhibited linear scaling (y = 0.6946x + 0.0088, R2 = 0.9988) within 0.025-5 ng/mL, with a lower limit of quantification of 25.00 pg/mL, high recovery (>70%) and low RSD (<7%). In Bactrian camels, IVM injection showed a low Cmax, extended Tmax and apparent secondary absorption compared to cattle and sheep. CONCLUSIONS: Slow absorption and widespread distribution were observed, with peak concentration and area under the curve correlating positively with the dose. This study provides insights into IVM pharmacokinetics in Bactrian camels, informing dose determination and highlighting potential metabolic differences compared to other livestock.

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D-amphetamine has been used to enhance cognitive performance over the last few decades. Due to the rapid absorption after administration, d-amphetamine shows narrow effective window and severe abuse potential. Lisdexamfetamine, a prodrug of d-amphetamine, reduces the magnitude of plasma d-amphetamine concentration and prolongs the action duration when compared with immediate-release d-amphetamine at equimolar doses. However, the differences of these two drugs, which produce distinct pharmacokinetic characteristics, in cognition improvement still unclear. In present study, we compared the effects of d-amphetamine (i.p) and lisdexamfetamine (p.o) at equimolar doses (0.2, 0.5, 1.5, 4.5, and 13.5 mg/kg of d-amphetamine base) on locomotion, spatial working memory and recognition memory in rats. Given the crucial involvement of dopamine neurotransmitter system within the medial prefrontal cortex (mPFC) in cognitive processing, microdialysis was conducted to profile the difference in neurochemical characteristics between the two drugs. In our results, d-amphetamine ranges from 0.5 to 1.5 mg/kg significantly increased locomotor activity. However, d-amphetamine ranges from 0.2 to 13.5 mg/kg failed to improve spatial working memory and recognition memory in Y-maze-based spontaneous alternation and two-trial delayed alternation tasks of rats, respectively. In contrast, lisdexamfetamine with 4.5 mg/kg significantly increased the locomotion and improved both spatial working and recognition memory. Further, microdialysis showed that lisdexamfetamine induced lower magnitude and longer duration of extracellular dopamine increase than that of d-amphetamine. These results suggest that lisdexamfetamine was more effective than d-amphetamine in improving spatial cognitive performance, which was attributed to the steady and lasting dopamine release pattern within the mPFC.

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Tetrahydropalmatine (THP), a tetrahydroproberine isoquinoline alkaloid, is widely present in some botanical drugs, such as Stephania epigaea H.S. Lo (Menispermaceae; Radix stephaniae epigaeae), Corydalis yanhusuo (Y.H.Chou & Chun C.Hsu) W.T. Wang ex Z.Y. Su and C.Y. Wu (Papaveraceae; Corydalis rhizoma), and Phellodendron chinense C.K.Schneid (Berberidaceae; Phellodendri chinensis cortex). THP has attracted considerable attention because of its diverse pharmacological activities. In this review, the chemical properties, plant sources, pharmacological activities, pharmacokinetic and toxicological characteristics of THP were systematically summarized for the first time. The results indicated that THP mainly existed in Papaveraceae and Menispermaceae families. Its pharmacological activities include anti-addiction, anti-inflammatory, analgesic, neuroprotective, and antitumor effects. Pharmacokinetic studies showed that THP was inadequately absorbed in the intestine and had rapid clearance and low bioavailability in vivo, as well as self-microemulsifying drug delivery systems, which could increase the absorption level and absorption rate of THP and improve its bioavailability. In addition, THP may have potential cardiac and neurological toxicity, but toxicity studies of THP are limited, especially its long-duration and acute toxicity tests. In summary, THP, as a natural alkaloid, has application prospects and potential development value, which is promising to be a novel drug for the treatment of pain, inflammation, and other related diseases. Further research on its potential target, molecular mechanism, toxicity, and oral utilization should need to be strengthened in the future.

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MW33 is a fully humanized IgG1κ monoclonal neutralizing antibody, and may be used for the prevention and treatment of coronavirus disease 2019 (COVID-19). We conducted a randomized, double-blind, placebo-controlled, single-dose, dose-escalation Phase 1 study to evaluate the safety, tolerability, pharmacokinetics (PK), and immunogenicity of MW33. Healthy adults aged 18-45 years were sequentially enrolled into the 4, 10, 20, 40, and 60 mg/kg dose groups and infused with MW33 over 60 ± 15 min and followed for 85 days. All 42 enrolled participants completed the MW33 infusion, and 40 participants completed the 85-day follow-up period. 34 participants received a single infusion of 4 (n = 2), 10 (n = 8), 20 (n = 8), 40 (n = 8), and 60 mg/kg (n = 8) of MW33. 27 subjects in the test groups experienced 78 adverse events (AEs) post-dose, with an incidence of 79.4% (27/34). The most common AEs included abnormal laboratory test results, vascular and lymphatic disorders, and infectious diseases. The severity of AEs was mainly Grade 1 (92 AEs), and three Grade 2 and one Grade 4. The main PK parameters, maximum concentration (Cmax), and area under the concentration-time curve (AUC0-t, and AUC0-∞) in 34 subjects showed a linear kinetic relationship in the range of 10-60 mg/kg. The plasma half-life was approximately 25 days. The positive rates of serum ADAs and antibody titres were low with no evidence of an impact on safety or PK. In conclusion, MW33 was well-tolerated, demonstrated linear PK, with a lower positive rate of serum ADAs and antibody titres in healthy subjects.Trial registration: ClinicalTrials.gov identifier: NCT04427501.Trial registration: ClinicalTrials.gov identifier: NCT04533048.Trial registration: ClinicalTrials.gov identifier: NCT04627584.

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Polysaccharide drugs are a type of safe and effective natural drug with a wide range of pharmacological activity such as anti-tumor, immunomodulation, and oxidation, and polysaccharide drugs are currently more concerned. However, since the molecular weight of the polysaccharide is quite large, most of which do not have ultraviolet absorption and fluorescent groups, which makes the qualitative and quantitative analysis of polysaccharides are relatively difficult. In addition, endogenous sugar substances may also cause certain interference to polysaccharide assay in biological samples, and therefore, in vivo metabolism and PK/PD key technologies in polysaccharide drugs have been research hotspots. This paper summarizes the relevant literature published in recent years, reviewing the biological activity and pharmacokinetics of polysaccharide drugs, proposing gut bacteria may be potential "organ" affecting metabolism and efficacy of polysaccharide drugs, and providing thoughts on gut bacteria mediating polysaccharide drugs in vivo and key technology research of PK/PD, in order to provide more scientific ideas for pharmacokinetics, pharmacological research and molecular mechanisms of polysaccharide drugs.

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INTRODUCTION: Tigecycline is a relatively new antibiotic that have very limited valid indications. When no other alternative is available, this drug is widely used off label with promising results. The objective of this study is to summarize the different off label uses of tigecycline so that we can decide when and how to prescribe it in the absence of guidelines. MATERIAL AND METHODS: This study a revue of the literature collecting all the articles concerning the off label uses of tigecycline. RESULTS: Tigecycline was widely prescribed, off label, to treat infections with controversial results. Randomised clinical trials were conducted to evaluate its use to treat pneumonia. The results for this indication have a respectable level of evidence. For the other indications, the data collected was insufficient to support tigecycline prescription. In fact, different protocols were used which makes it hard to evaluate the efficacy and to conclude to the best treatment regimen. A tendency to prescribe high doses of the molecule was noted in different studies. When prescribed off label, tigecycline prescriptions were associated with a higher mortality and incidence of side effects. CONCLUSION: The tigecycline remains a valid option for the treatment of infections dues to multi-resistant bacteria especially when other alternatives are scarce or in cases of renal failure.

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Ethno Pharmacological Relevance: Acetylharpagide is a monomeric compound extracted from Ajuga decumbens, widely used for remedying infectious and inflammatory diseases in Southern China. Aim of the Study: The present study designed and investigated the formulation of colon-targeted acetylharpagide tablets according to the dual controlled release mechanisms of time-delay and pH-sensitivity. Materials and Methods: The core tablets of acetylharpagide were coated with the material used in time-delay systems such as ethyl cellulose and suitable channeling agent, followed by pH-dependent polymers, polyacrylic resin II and III in a combination of 1:4. Furthermore, the release and absorption performance of colon-targets tables were evaluated in vitro and in vivo. In the in vitro tests, the optimized formulation was not released in simulated gastric fluid in 2 h; the release was <5% at pH 6.8 simulated intestinal fluids for 4 h; the drug was completely released within 5 h at pH 7.6 simulated colon fluid. In the in vivo tests, pharmacokinetic characteristics of the colon-targeted tablets were investigated in dogs. Results: The results indicated that the acetylharpagide tablets with the technology of colon-targeting caused delayed Tmax, prolonged absorption time, lower Cmax, and AUCINF_obs. Meanwhile, the apparent volume of distribution (Vz_F_bs) of the colon-target tablets was higher than the reference. Conclusions: These results suggested that colon-targeted acetylharpagide tablets deliver the drug to the colon. The in vitro performance of colon-targeted acetylharpagide tablet was appropriately correlated with its performance in vivo.

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Ginkgo terpene lactones, as an important active ingredient from Ginkgo leaves, has high medicinal values and has been widely used in clinics. This article would review the researches both at home and abroad, including chemical composition, structure-activity relationship, analytical methods, pharmacological effects, pharmacokinetic characteristics, and so on, providing a reference for further development and utilization of ginkgo terpene lactones.

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Liposomal formulations entrapping a vast number of molecules have improved cancer therapies overcoming certain pharmacokinetic (PK) and pharmacodynamic limitations, many of which are associated with tumor characteristics. In this context, immunoliposomes represent a new strategy that has been widely investigated in preclinical cancer models with promising results, although few have reached the stage of clinical trials. This contrasts with the emerging clinical application of monoclonal antibodies (mAbs). This formulation allows the conjugation of different mAbs or antibody derivatives, such as monovalent variable fragments Fab', to the polymers covering the surface of liposomes. The combination of this targeting strategy together with drug encapsulation in a single formulation may contribute to enhance the efficacy of these associated agents, reducing their toxicities. In this paper we will consider how factors such as particle size, lipid composition and charge, lipid-polymer conjugation, method of production and type of ligand for liposome coupling influence the efficacy of these formulations. Furthermore, the high inter-individual variability in the tumor microenvironment, as well as the poor experimental designs for the PK characterization of liposomes, make the establishment of the relationship between plasma or tumor concentrations and efficacy difficult. Thus, adequate dosing regimens and patient stratification regarding the target expression may contribute to enhance the possibility of incorporating these immunoliposomes into the therapeutic arsenal for cancer treatments. All these issues will be briefly dealt with here, together with a section showing the state of the art of those targeted liposomes that are coming up for testing in clinical trials. Finally, some insights into future developments such as the combination of specificity and controlled release, based on the application of different stimuli, for the manipulation of stability and cargo release, will be offered. This has been included in order to highlight the new opportunities for targeted liposomes, including immunoliposomes.

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Ginkgo terpene lactones, as an important active ingredient from Ginkgo leaves, has high medicinal values and has been widely used in clinics. This article would review the researches both at home and abroad, including chemical composition, structure-activity relationship, analytical methods, pharmacological effects, pharmacokinetic characteristics, and so on, providing a reference for further development and utilization of ginkgo terpene lactones.

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Drug metabolism plays an important role in the drug disposal process. Differences in pharmacokinetics among individuals are the basis for personalized medicine. Natural medicines, formed by long-term evolution of nature, prioritize the action of a target protein with a drug. Natural medicines are valued for structural diversity, low toxicity, low cost, and definite biological activities. Metabolic pathway and pharmacokinetic research of natural medicines is highly beneficial for clinical dose adjustment and the development of personalized medicine. This review was performed using a systematic search of all available literature. It provides an overview and discussion of metabolic pathways and the pharmacokinetics of natural medicines with low permeability. The related enzymes and factors affecting them are analyzed. The series of metabolic reactions, including phase I reactions(oxidation hydrolysis, and reduction reactions) and phase II reactions (binding reactions), catalyzed by intracellular metabolic enzymes (such as CYP450, esterase, SULT, and UGT enzymes) in tissues (such as liver and gastro-intestinal tract) or in the body fluid environment were examined. The administration route, drug dose, and delivery system had a large influence on absorption, metabolism, and pharmacokinetics. Natural medicines with low permeability had distinctive metabolisms and pharmacokinetics. The metabolic and in vivo kinetic properties were favorably modified by choosing suitable drug delivery systems, administration routes and drug doses, among other variables. This study provides valuable information for clinicians and pharmacists to guide patients safe, effective, and rational drug use. The research of metabolism and pharmacokinetics is significant in guiding personalized clinical medicine.

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We previously prepared and evaluated simple Eudragit S100 microparticles loaded with prednisolone (ES-MP) and Eudragit S100-coated chitosan-succinyl-prednisolone conjugate microparticles (Ch-MP/ES) in vitro. In this work, the effectiveness, toxic side effects (5 mg prednisolone (PD) eq/kg × 3 d, 10 mg PD eq/kg × 3 d), and pharmacokinetic characteristics (5 mg PD eq/kg) were examined using rats with colitis induced through 2,4,6-trinitrobenzenesulfonic acid. ES-MP did not change the efficacy or toxic side effects of PD, and this was attributed to incomplete delivery to the target site and prolonged systemic drug absorption by ES-MP. On the other hand, Ch-MP/ES promoted the efficacy of PD and ameliorated its toxic side effects due to better delivery to the target site, very slow drug release and the strong suppression of drug absorption. Only Ch-MP/ES, which markedly changed drug release characteristics, improved the in vivo features of PD.

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Aim To study the pharmacokinetic char-acteristics of serial compounds that took the scutellarin and scutellarein as lead compounds by using the model of in vitro liver microsomes, and to screen compounds whose medicinal properties were superior to scutellarin and scutellarein. Methods The content of candidate compounds at different times by incubation system of rat liver microsome was determined using UPLC-MS/MS method. Candidate compounds that contained opti-mum T1/2 and CLint were screened. Enzyme kinetics and conversions of candidate compounds were com-pared with those of scutellarin and scutellarein. Re-sults The T1/2 and CLint were optimum of W11 com-pared with those of scutellarin and scutellarein; the Vmax, Km and CLint of compound W11 were (10.25 ±2.59 ) μmol · min-1 · g-1 , ( 4.64 ±0.24 ) μmol · L-1 and ( 2.29 ±0.23 ) L · min-1 · g-1; the Vmax , Km and CLint of scutellarin were (45.95±9.50) μmol · min-1 · g-1 , ( 10.19 ± 1.66 ) μmol · L-1 and (4.48±0.20) L·min-1 ·g-1; W11 might be me-tabolized into scutellarin and M1 ( a compound with mo-lecular weight of 577 after demethylating ) . Conclu-sion The pharmacokinetic properties of candidate compound W11 are better than those of scutellarin, and it could release scutellarin.

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A conjugate between chondroitin sulfate (CS) and glycyl-prednisolone (GP), named CS-GP, was prepared as a delivery system for the treatment of rheumatoid arthritis by referring to the previous report. CS-GP conjugates with different prednisolone (PD) contents of 1.4, 2.0 and 4.3% (w/w) were obtained, and their conversion characteristics were investigated at 37 °C under pH 6 and 7.4. Release profiles were similar among the conjugates, being slow at pH 6 (24 h: 9-14%), and fairly fast at pH 7.4 (7 h: 46-58%). CS-GP, PD, CS and the PD/CS mixture were investigated for anti-inflammatory effects by i.v. administration to rats with adjuvant-induced arthritis. At 2.5mg PD equiv./kg×2 d, CS-GP significantly suppressed swelling of both hind paws, while other preparations were less effective. CS-GP (2.5mg PD equiv./kg×2 d) tended to be more effective than PD (5 mg/kg×2 d). Change in body weight indicated that CS-GP was not toxic. After i.v. injection in normal rats, CS-GP showed much higher plasma levels than PD alone, and organ accumulation of CS-GP was not observed. CS-GP was suggested to be possibly useful for the treatment of rheumatoid arthritis.

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