An indicator of antioxidant stress ability to evaluate neurofunctional changes in patients with acute ischemic stroke: preliminary findings.

Background: Acute ischemic stroke (AIS) ranks among the most prevalent cerebrovascular conditions. The clinical interest lies in utilizing oxidative stress (OS) markers and antioxidant system indicators for diagnosing and predicting stroke development. Our objective was to identify a precise marker of antioxidant stress ability to assess neurofunctional alterations in AIS patients.

Simultaneous Determination of Unbound Plasma Concentration of Methotrexate and 7-Hydroxymethotrexate in Children Patients Receiving High-Dose Methotrexate Therapy.

Background: High-dose methotrexate (HD-MTX) is seen as an effective therapy for acute lymphoblastic leukemia (ALL); however, it is extremely toxic. Monitoring the plasma concentrations of methotrexate (MTX) and its important metabolite, 7-hydroxy-methotrexate (7-OH-MTX), on a routine basis aids in dose modification of rescue medications and in avoiding toxicity. The pharmacologically active and toxic effects of drugs are due to the unbound portion, as most drugs are bound to plasma proteins to some degree.

Development of an hollow fiber solid phase microextraction method for the analysis of unbound fraction of imatinib and N-desmethyl imatinib in human plasma.

Therapeutic drug monitoring (TDM) of imatinib (IM) in cancer therapy offers the potential to improve treatment efficacy while minimizing toxicity. There was a significant correlation between unbound concentration and clinical response and toxicity, compared with total plasma concentrations, and the quantification of unbound IM and its metabolite, N-desmethyl imatinib (NDI) are of interest for TDM. However, traditional unbound drug separation methods have shortcomings, especially are susceptible to non-specific binding (NSB) of drugs to the polymer-constructed components of filter membranes, which are difficult to avoid at present.

Impact of homocysteine on acute ischemic stroke severity: possible role of aminothiols redox status.

Background: Acute ischemic stroke (AIS) is one of the most common cerebrovascular diseases which accompanied by a disruption of aminothiols homeostasis. To explore the relationship of aminothiols with neurologic impairment severity, we investigated four aminothiols, homocysteine (Hcy), cysteine (Cys), cysteinylglycine (CG) and glutathione (GSH) in plasma and its influence on ischemic stroke severity in AIS patients.

Methods: A total of 150 clinical samples from AIS patients were selected for our study.

A more accurate indicator to evaluate oxidative stress in rat plasma with osteoporosis.

: oxidative stress is linked to various human diseases which developed into the idea of "disrupted redox signaling". Osteoporosis (OP) is a chronic skeletal disorder characterized by low bone mineral density and deterioration of bone microarchitecture among which estrogen deficiency is the main cause. Lack of estrogen leads to the imbalance between oxidation and anti-oxidation in patients, and oxidative stress is an important link in the pathogenesis of OP.

Analysis of free concentrations of lamotrigine and active oxcarbazepine metabolite in clinical patients by hollow-fiber centrifugal ultrafiltration.

To establish a simple and accurate method to explore the correlation between free and total concentrations of lamotrigine (LTG) and the active oxcarbazepine metabolite monohydroxy derivative (MHD) (10,11-dihydro-10-hydroxycarbamazepine) in clinical patients. Serum samples were prepared by hollow-fiber centrifugal ultrafiltration and then injected into UPLC for analysis. Absolute recovery was as high as approximately 90.

A simple and accurate HFCF-UF method for the analysis of homocysteine, cysteine, cysteinyl-glycine, and glutathione in human blood.

The presence of reduced aminothiols, including homocysteine (Hcy), cysteine (Cys), cysteinyl-glycine (CG), and glutathione (GSH), is significantly increased in the pathological state. However, there have been no reports on the relationship between reduced aminothiols (Hcy, Cys, CG, and GSH) and different genders, ages, and drug combinations in human blood. The accurate quantification of these reduced thiols in biological fluids is important for monitoring some special pathological conditions of humans.

Relationship Between the Free and Total Methotrexate Plasma Concentration in Children and Application to Predict the Toxicity of HD-MTX.

High-dose methotrexate (HD-MTX) can be highly effective as well as extremely toxic. Many drug molecules can bind to plasma proteins to different extents , whereas only the free drug can reach the site of action to exert a pharmacological effect and cause toxicity. However, free MTX concentrations in plasma have not been reported.

Triplanar Chevron Osteotomy: A Newly Proposed Method to Treat Hallux Valgus Deformities.

Objective: To present a novel method called triplanar chevron osteotomy to treat hallux valgus (HV).

Methods: This is a retrospective study. In this study, the CT data of HV patients with painful callosities were evaluated retrospectively between 1 June 2018 and 1 June 2020.

A Direct Injection Technique to Improve Biosafety to Analyze Levetiracetam Concentrations in Human Serum and Its Application in Therapeutic Drug Monitoring.

Background: With the outbreak of COVID-19, it has become very important to improve biosafety measures taken by medical staff. Fewer pretreatment steps correspond to lower chances of infection. The authors established a direct injection technique to analyze levetiracetam (LEV) concentrations in human serum and studied its application in therapeutic drug monitoring.

The Influence of Plasma Albumin Concentration on the Analysis Methodology of Free Valproic Acid by Ultrafiltration and Its Application to Therapeutic Drug Monitoring.

Background: Free drug analysis is increasingly becoming popular in therapeutic drug monitoring (TDM). Centrifugal ultrafiltration (CF-UF) is the primary method to separate free drug from that of bound drug. However, the volume ratio of ultrafiltrate to sample solution (Vu/Vs) affects the accuracy of CF-UF, which highly depends on the different plasma conditions.

A new derivatization method to enhance sensitivity for the determination of low levels of valproic acid in human plasma.

A novel and sensitive high-performance liquid chromatographic (HPLC) method has been developed and validated for the determination of valproic acid (VPA) in human plasma. The method was based on derivatization of VPA using 2-bromo-2'-acetonaphthone as a new derivatization reagent. Caprylic acid was used as an internal standard (IS).

The influence of volume ratio of ultrafiltrate of sample on the analysis of non-protein binding drugs in human plasma.

In human plasma, the total concentration of non-protein binding (NPB) drugs is equal to the free drug concentration because NPB drugs do not or hardly bind to plasma proteins. Thus, centrifuge ultrafiltration (CF-UF) has been used in the determination of the concentration of NPB drugs in human plasma. However, with only a common centrifugation, the recovery and the reproducibility were not as excellent as expected.

Accuracy assessment on the analysis of unbound drug in plasma by comparing traditional centrifugal ultrafiltration with hollow fiber centrifugal ultrafiltration and application in pharmacokinetic study.

In present study, accuracy assessment on the analysis of unbound drug in plasma was made by comparing traditional centrifugal ultrafiltration (CF-UF) with hollow fiber centrifugal ultrafiltration (HFCF-UF). We used metformin (MET) as a model drug and studied the influence of centrifugal time, plasma condition and freeze-thaw circle times on the ultrafiltrate volume and related effect on the measurement of MET. Our results demonstrated that ultrafiltrate volume was a crucial factor which influenced measurement accuracy of unbound drug in plasma.

Effect of volume ratio of ultrafiltrate to sample solution on the analysis of free drug and measurement of free carbamazepine in clinical drug monitoring.

Traditional ultrafiltration (UF) usually has a large volume ratio of ultrafiltrate to sample solution, and this ratio cannot be well controlled. It can break the balance of protein-binding equilibrium and exert an influence on the analysis of free drug. In the present study, we evaluated the influence of volume ratio of ultrafiltrate to sample solution on the analysis of free drug in human plasma.

A simple sample preparation method for measuring amoxicillin in human plasma by hollow fiber centrifugal ultrafiltration.

A simple sample preparation method has been developed for the determination of amoxicillin in human plasma by hollow fiber centrifugal ultrafiltration (HF-CF-UF). A 400-μL plasma sample was placed directly into the HF-CF-UF device, which consisited of a slim glass tube and a U-shaped hollow fiber. After centrifugation at 1.