OBJECTIVES

In response to the need for a simple and fast way of ensuring that generic drugs especially those that contain rifampicin are bioequivalent with reference drugs, this study validated an ultra-high-performance liquid chromatography (UHPLC) method of quantifying rifampicin in human plasma. The study also validated the method's selectivity, linearity, sensitivity, accuracy, precision, and the absence of a carry-over effect adhering to the Philippine Food and Drug Administration guidelines.

Plasma samples were prepared via protein precipitation using methanol containing ascorbic acid. Three microliters (3 uL) of the prepared samples were then analyzed in a Waters Acquity H-Class UPLC® system coupled to a tunable ultraviolet (TUV) detector with an attached UPLC® BEH C-18 column using a developed and optimized method. Briefly, the column temperature was set to 40°C and the sample temperature was set to 10°C. Elution was done using a linear gradient flow of a water-acetonitrile mixture that started with 45% acetonitrile increasing to 60% acetonitrile at 0.5 minutes and back to 45% acetonitrile at 3 minutes and having a constant flow rate of 0.5 mL/min. Detection was done at 340 nm. Method validation was performed following the ICH guidelines for Bioanalytical Method Validation, the same guidelines referenced by the ASEAN Guideline for Harmonisation of Standards and the Philippine Food and Drug Administration (FDA).

The method had an analysis time of 3 minutes wherein rifampicin eluted at 1.4 minutes while the internal standard, rifapentine (IS) eluted at 1.7 minutes. Since no co-eluting endogenous materials were observed for the rifampicin and the internal standard, the method was confirmed to be selective. Its linearity over the range of 2 ug/mL to 25 ug/mL has been validated where it has a limit of detection (LOD) and limit of quantification (LOQ) values of 0.64 ug/mL and 1.94 ug/mL, respectively. The interday and intraday precision, reported as % coefficient of variance (%CV), and interday and intraday accuracy, reported as %error all within the limits of ±20% for the LLOQ and ±15% for the rest indicating its reliability and reproducibility. Lastly, due to the nature of the injection of the sample into the system, wherein a blank immediately follows the highest concentration standard, the method has been cleared of a carry-over effect.

The study successfully validated a UHPLC method of quantifying rifampicin in human plasma. Due to the sample processing method used and the chromatographic conditions set, the method can prepare and analyze samples in a simple yet fast, sensitive, reliable, and reproducible manner. The method can be applied in bioavailability and bioequivalence studies of rifampicin.

Objectives: The Bioavailability/Bioequivalence Unit (BA/BE Unit) of the Department of Pharmacology and Toxicology, College of Medicine, University of the Philippines Manila which has not been operational since 2012, is due for renewal of its accreditation. To date, there are only three Philippine Food and Drug Administration-accredited laboratories that perform bioequivalence studies in the Philippines. One of the prerequisites of registering specific generic medicines is the conduct of Bioequivalence (BE) studies which are performed to ensure that the generic drug is at par with the innovator drug. Thus, this study aimed to determine the feasibility of re-establishing the BA/BE Unit as a bioequivalence testing center. Methods: The feasibility study done is a qualitative descriptive analysis based on expansive literature review and performance of SWOT analysis within the BA/BE unit. Literatures were selected based on its assessed relevance to the study. The databases checked were PubMed and Google Scholar. The terms used were from the Medical Subject Heading (MeSH) including feasibility studies, therapeutic equivalency, and generic drugs. Literature review was performed on the factors affecting the four types of feasibility studies (market, technical, financial, and organizational). A SWOT analysis of the BA/BE Unit was done through the review of records and documents of previous BE studies and focus group discussion among the BA/BE Unit team members. Results: The BA/BE Unit conducted 24 bioequivalence studies from 2006-2009 and still receives inquiries from drug companies. It implements its QMS throughout the pre-analytical, analytical, and post-analytical stages of the workflow. Its organizational structure consists of qualified professionals with updated GCP and GLP certificates. Because of the adequately equipped facility, lower honoraria for government-employed personnel, and lower expenses for laboratories and in-patient admissions, the cost of conducting a bioequivalence study in the BA/BE Unit will be lower than in other BE centers. Conclusion Based on the SWOT analysis and market, technical, financial, and organizational considerations, reestablishing the BA/BE Unit as a bioequivalence testing center is feasible.
Feasibility Studies ; Therapeutic Equivalency ; Drugs, Generic

OBJECTIVE: Exosomal long noncoding RNAs (lncRNAs) are the key to diagnosing and treating various diseases. This study aimed to investigate the diagnostic value of plasma exosomal lncRNAs in white matter hyperintensities (WMH). METHODS: We used high-throughput sequencing to determine the differential expression (DE) profiles of lncRNAs in plasma exosomes from WMH patients and controls. The sequencing results were verified in a validation cohort using qRT-PCR. The diagnostic potential of candidate exosomal lncRNAs was proven by binary logistic analysis and receiver operating characteristic (ROC) curves. The diagnostic value of DE exo-lncRNAs was determined by the area under the curve (AUC). The WMH group was then divided into subgroups according to the Fazekas scale and white matter lesion site, and the correlation of DE exo-lncRNAs in the subgroup was evaluated. RESULTS: In our results, four DE exo-lncRNAs were identified, and ROC curve analysis revealed that exo-lnc_011797 and exo-lnc_004326 exhibited diagnostic efficacy for WMH. Furthermore, WMH subgroup analysis showed exo-lnc_011797 expression was significantly increased in Fazekas 3 patients and was significantly elevated in patients with paraventricular matter hyperintensities. CONCLUSION Plasma exosomal lncRNAs have potential diagnostic value in WMH. Moreover, exo-lnc_011797 is considered to be a predictor of the severity and location of WMH.
Humans ; RNA, Long Noncoding/genetics* ; White Matter ; Area Under Curve ; Exosomes/genetics* ; High-Throughput Nucleotide Sequencing

Uric acid (UA) is the final product of purine metabolism in human body,and its metabolic disorder will induce hyperuricemia (HUA).The occurrence and development of HUA are associated with a variety of pathological mechanisms such as oxidative stress injury,activation of inflammatory cytokines,and activation of renin-angiotensin-aldosterone system.These mechanisms directly or indirectly affect the bioavailability of endogenous nitric oxide (NO).The decrease in NO bioavailability is common in the diseases with high concentration of UA as an independent risk factor.In this review,we summarize the mechanisms by which high concentrations of UA affect the endogenous NO bioavailability,with a focus on the mechanisms of high-concentration UA in decreasing the synthesis and/or increasing the consumption of NO.This review aims to provide references for alleviating the multisystem symptoms and improving the prognosis of HUA,and lay a theoretical foundation for in-depth study of the correlations between HUA and other metabolic diseases.
Humans ; Nitric Oxide ; Uric Acid ; Hyperuricemia ; Biological Availability ; Cytokines

It is a significant challenge to improve the blood-brain barrier (BBB) permeability of central nervous system (CNS) drugs in their development. Compared with traditional pharmacokinetic property tests, machine learning techniques have been proven to effectively and cost-effectively predict the BBB permeability of CNS drugs. In this study, we introduce a high-performance BBB permeability prediction model named balanced-stacking-learning based BBB permeability predictor(BSL-B3PP). Firstly, we screen out the feature set that has a strong influence on BBB permeability from the perspective of medicinal chemistry background and machine learning respectively, and summarize the BBB positive(BBB+) quantification intervals. Then, a combination of resampling algorithms and stacking learning(SL) algorithm is used for predicting the BBB permeability of CNS drugs. The BSL-B3PP model is constructed based on a large-scale BBB database (B3DB). Experimental validation shows an area under curve (AUC) of 97.8% and a Matthews correlation coefficient (MCC) of 85.5%. This model demonstrates promising BBB permeability prediction capability, particularly for drugs that cannot penetrate the BBB, which helps reduce CNS drug development costs and accelerate the CNS drug development process.
Blood-Brain Barrier ; Algorithms ; Area Under Curve ; Databases, Factual ; Permeability

OBJECTIVE: To calculate the pharmacokinetic parameters of recombinant human coagulation factor Ⅷ using myPKFiT in patients with severe hemophilia A, and provide an individualized treatment plan for patients. METHODS: A total of 42 patients with severe hemophilia A who were treated with recombinant human coagulation factor Ⅷ were included from January 2021 to December 2021. myPKFiT was used to calculate the pharmacokinetic parameters of FⅧ, and the individualized treatment plan for hemophilia A patients was formulated. RESULTS: The median age of 42 patients with severe hemophilia A was 31（16-50） years old, the average weight was 54.0±9.9 kg, the half-life of FⅧ was 12.05±1.6 h, the time to more than 1% of the baseline was 62.3±15.3 h, and the 0 bleeding rate after the guidance of myPKFiT was significantly increased from 39% to 49%, the Annual bleeding rate was reduced from 3.6±2.5 to 2.1±2.0, and the Annual joint bleeding rate was reduced from 3.2±2.2 to 1.9±0.9, all of which were statistically different (<i>Pi><0.05). CONCLUSION Individualized therapy in patients with severe hemophilia A who were guided by myPKFiT assay of pharmacokinetics parameters can significantly reduce the annual bleeding rate and annual joint bleeding rate of patients.
Adult ; Humans ; Middle Aged ; Blood Coagulation Factors ; Factor VIII/pharmacokinetics* ; Hemophilia A ; Hemorrhage ; Recombinant Proteins/pharmacokinetics* ; Adolescent ; Young Adult

A growing body of evidence has linked the gut microbiota to liver metabolism. The manipulation of intestinal microflora has been considered as a promising avenue to promote liver health. However, the effects of <i>Lactobacillus gasserii> LA39, a potential probiotic, on liver metabolism remain unclear. Accumulating studies have investigated the proteomic profile for mining the host biological events affected by microbes, and used the germ-free (GF) mouse model to evaluate host-microbe interaction. Here, we explored the effects of <i>L. gasserii> LA39 gavage on the protein expression profiles of the liver of GF mice. Our results showed that a total of 128 proteins were upregulated, whereas a total of 123 proteins were downregulated by treatment with <i>L. gasserii> LA39. Further bioinformatics analyses suggested that the primary bile acid (BA) biosynthesis pathway in the liver was activated by <i>L. gasserii> LA39. Three differentially expressed proteins (cytochrome P450 family 27 subfamily A member 1 (CYP27A1), cytochrome P450 family 7 subfamily B member 1 (CYP7B1), and cytochrome P450 family 8 subfamily B member 1 (CYP8B1)) involved in the primary BA biosynthesis pathway were further validated by western blot assay. In addition, targeted metabolomic analyses demonstrated that serum and fecal β‍-muricholic acid (a primary BA), dehydrolithocholic acid (a secondary BA), and glycolithocholic acid-3-sulfate (a secondary BA) were significantly increased by <i>L. gasserii> LA39. Thus, our data revealed that <i>L. gasserii> LA39 activates the hepatic primary BA biosynthesis and promotes the intestinal secondary BA biotransformation. Based on these findings, we suggest that <i>L. gasserii> LA39 confers an important function in the gut‒liver axis through regulating BA metabolism.
Mice ; Animals ; Bile Acids and Salts/metabolism* ; Lactobacillus gasseri ; Proteomics ; Liver/metabolism* ; Biotransformation

Many natural products can be bio-converted by the gut microbiota to influence pertinent efficiency. Ginsenoside compound K (GCK) is a potential anti-type 2 diabetes (T2D) saponin, which is mainly bio-transformed into protopanaxadiol (PPD) by the gut microbiota. Studies have shown that the gut microbiota between diabetic patients and healthy subjects are significantly different. Herein, we aimed to characterize the biotransformation of GCK mediated by the gut microbiota from diabetic patients and healthy subjects. Based on 16S rRNA gene sequencing, the results indicated the bacterial profiles were considerably different between the two groups, especially Alistipes and Parabacteroides that increased in healthy subjects. The quantitative analysis of GCK and PPD showed that gut microbiota from the diabetic patients metabolized GCK slower than healthy subjects through liquid chromatography tandem mass spectrometry (LC-MS/MS). The selected strain A. finegoldii and P. merdae exhibited a different metabolic capability of GCK. In conclusion, the different biotransformation capacity for GCK may impact its anti-diabetic potency.
Humans ; Gastrointestinal Microbiome/genetics* ; Chromatography, Liquid/methods* ; Healthy Volunteers ; RNA, Ribosomal, 16S ; Feces/microbiology* ; Tandem Mass Spectrometry ; Biotransformation ; Diabetes Mellitus, Type 2/drug therapy*

Traditional Chinese medicine(TCM) has a long history and abundant experience in external therapy, which marks human wisdom. In the early history of human, people found that fumigation, coating, and sticking of some tree branches and herb stems can help alleviate scabies and remove parasites in productive labor, which indicates the emergence of external therapy. Pathogen usually enters the body through the surface, so external therapy can be used to treat the disease. External therapy is among the major characteristic of surgery of TCM. As one of the external therapies in TCM, external application to acupoints smooths the zang-fu organs through meridians and collaterals, thereby harmonizing yin and yang. This therapy emerged in the early society, formed the Spring and Autumn Period and the Warring States Period, improved in the Song and Ming dynasties, and matured in the Qing dynasty. With the efforts of experts in history, it has had a mature theory. According to modern research, it can avoid the first-pass effect of liver and the gastrointestinal irritation and improve the bioavailability of Chinese medicine. Based on the effect of Chinese medicine and the theory of meridian and collateral, it can stimulate the acupoints, exert regulatory effect on acupoints, and give full play to the efficacy of TCM and the interaction of the two. Thereby, it can regulate qi and blood and balance yin and yang, thus being widely used in the treatment of diseases. In this paper, the use of external application to acupoints, the effect on skin immunity, the regulation of neuro-inflammatory mechanism, the relationship between acupoint application and human circulation network, and the development of its dosage form were summarized through literature review. On this basis, this study is expected to lay a foundation for further research.
Humans ; Acupuncture Points ; Biological Availability ; Fumigation ; Medicine, Chinese Traditional ; Meridians

Huoluo Xiaoling Dan is a classical prescription commonly used for blood circulation and pain relief in clinic with obvious effects. To make it directly treat lesion and improve the effect, this research optimized the preparation process of Huoluo Xiaoling gel paste and further evaluated its in vitro transdermal absorption performance, so as to provide a scientific basis for its development and utilization. Using primary viscosity, holding viscosity, and sensory score as evaluation indexes, the matrix amount of gel paste was determined by the single factor test and Box-Behnken response surface method. The ultra-performance liquid chromatography(UPLC) method was established to determine the content of eight active ingredients, including Danshensu, ferulic acid, salvianolic acid B, salvianolic acid A, ligustilide, tanshinone Ⅱ_A, 11-keto-β-boswellic(KBA), and 3-acetyl-11-keto-β-boswellic acid(AKBA). A mo-dified Franz diffusion cell method was used to evaluate and compare the absorption properties of the gel paste without volatile oil and with volatile oil microemulsion. The results showed that the optimal prescription for Huoluo Xiaoling gel paste matrix was NP700(1.35 g), glycerol(7.00 g), micropowder silica gel(1.25 g), sodium carboxymethyl cellulose(0.20 g), tartaric acid(0.06 g), and glyceryl aluminum(0.04 g). The mass fractions of eight active ingredients in the paste were successively 0.48, 0.014, 0.95, 0.39, 0.57, 0.055, 0.35, and 0.97 mg·g~(-1). The results of the in vitro transdermal absorption test showed that the addition of the volatile oil or the volatile oil microemulsion promoted the transdermal absorption of the active ingredients, and the law of drug penetration conformed to the zero equation or the Higuchi equation. The gel paste prepared by the optimal prescription has good appearance and adhesion, with no residue, and has the characteristics of skeletal slow-release preparation, which is easy to reduce the number of administration, la-ying a foundation for the development of new external dosage forms of Huoluo Xiaoling Dan.
Administration, Cutaneous ; Skin Absorption ; Chromatography, Liquid ; Oils, Volatile ; Viscosity