[Comparison of the early analgesic efficacy of three different drugs after anterior cruciate ligament reconstruction].

OBJECTIVE: The pain-relieving effect and safety of compound aminopyrine phenacetin tablets, tramcontin (tramadol hydrochloride sustained-release tablets) and dolantin in the early stage of autologous tendon reconstruction of the anterior cruciate ligament (ACL) of the knee joint were compared. METHODS: Retrospective analysis of postoperative pain and drug analgesia in 45 patients performed by the same group from November 2018 to February 2019. The random area group design was divided into two groups according to whether ACL rupture was combined with meniscal injury, group A was 24 patients with ACL reconstruction of knee joint and group B was 21 patients with ACL fracture combined with meniscus injury. The two groups were divided into three subgroups respectively according to the actual treatment of postoperative analgesic drugs received by the patients, including 4 cases of compound aminopyrine phenacetin tablets, 11 cases of oral tramcontin, 9 cases of intramuscular dolantin combined with phenergan in group A; 3 cases of compound aminopyrine phenacetin tablets, 10 cases of oral tramcontin, and 8 cases of intramuscular dolantin combined with phenergan in group B. When the early postoperative patients complain about pain and actively ask for analgesia. When the patients complained about pain after the operation and actively asked for analgesia, they were randomly given painkillers, tramcontin or dolantin combined with phenergan to relieve pain. Pain visual analogue scale (VAS) was used to evaluate pain relief and observe the occurrence of adverse reactions. RESULTS: There were no significant dif-ferences in gender, age, body mass index, and time of hospital stay between the two groups of patients (P > 0.05). In the patients who used tramcontin and dolantin combined with phenergan to relieve pain judging by VAS score before and 1 h after taking the drug, it was found that the pain situation of the patient was significantly relieved, and the difference before and after taking the drug had statistical significance (P < 0.05). Pairwise comparisons of the three drugs applied in the two groups showed significantly greater pain relief in the dolantin combined with phenergan group than in the remaining two drugs. There was no significant difference (P > 0.05). Dolantin was prone to nausea and vomiting, but the application of phenergan was also used to reduce side effects. In terms of adverse reactions, only 1 case of nausea occurred in the tramcontin group for simple ACL reconstruction, and none of the patients in the other groups showed serious complications and allergic reactions. CONCLUSION: Whether in cruciate ligament reconstruction alone or combined with meniscus molding or suture, compound aminopyrine phenacetin tablets, tramcontin, dolantin combined with phenergan can effectively relieve pain. Among the three drugs, dolantin caused the largest pain relief. At the same time, the combination of phenergan effectively reduced the adverse reactions, such as vomiting and nausea, and increased the drug safety.

Development of a highly sensitive immunoassay for detecting aminopyrine abuse in herbal tea.

With the popularity of herbal tea in China, many food fraudsters have added illegal drugs to herbal tea to enhance its functions, among which aminopyrine is widely abused as an antipyretic and analgesic. Presently, there is no immunoassays for aminopyrine, and it is difficult to achieve real-time detection in the field. Based on a polyclonal antibody of aminopyrine with high specificity and sensitivity, an optimal combination of coating antigen/antibody was obtained by screening different coating antigens. On this basis, a sensitive ic-ELISA method was established to detect aminopyrine in herbal tea. The detection limit of the ic-ELISA was 0.18 ng mL-1, which was much lower than the 100 ng mL-1 required as a standard. The method had good consistency with LC-MS in the detection of actual samples and could be used as a reliable method for the detection of aminopyrine in herbal tea.

Developing an ultrasensitive immunochromatographic assay for authentication of an emergent fraud aminopyrine in herbal tea.

Aminopyrine is a nonsteroidal anti-inflammatory drug only for medical purposes, however, it has been illegally added in traditional Chinese herbal teas for fraud activity recently. In this study, a specific antibody against aminopyrine with IC50 of 3.00 ng/mL was obtained for the first time by a rational hapten design. Furthermore, an ultrasensitive gold nanoparticles immunochromatographic assay (AuNPs-ICA) for determination of aminopyrine based on a portable reader was firstly developed, with cut-off value of 100.00 ng/mL, limit of detection (LOD) of 4.80 ng/mL and limit of quantification (LOQ) of 5.71 ng/mL for herbal tea, respectively. The recovery rates ranged from 93.21 % to 105.61 %, with inter-assay coefficient of variation (CV) from 1.08 % to 3.82 %. Additionally, 24 blind samples were examined simultaneously by AuNPs-ICA and LC-MS/MS, demonstrating a good consistency for each other. The proposed AuNPs-ICA is an ultrasensitive and reliable tool for on-site surveillance screening of fraud additives in herbal tea.

[Determination of dimethyl sulfate genotoxic impurities in tertiary amine drugs by ultra-high performance liquid chromatography-tandem mass spectrometry].

Dimethyl sulfate is an important chemical raw material that is widely used in the synthesis of drugs, dyes, spices, and pesticides. The highly toxic and corrosive dimethyl sulfate residue in medicines is harmful to the human body, and hence, the residue level should be strictly controlled. Traditional detection methods use high-purity acetonitrile and anhydrous as the solvents, which limits the choice of detection solvents and degrades the versatility and accuracy of detection. Therefore, a simple and accurate method for the determination of dimethyl sulfate residues is urgently needed. Dimethyl sulfate is usually detected by ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) with pyridine as the methylation substrate. In this study, a new method for the detection of dimethyl sulfate was established using tertiary amines such as aminophenazone, which has many advantages over pyridine, as the methylation substrate. For example, the hybrid orbital and electron cloud of the N atom are different, resulting in stronger nucleophilicity of aminophenazone. High temperatures that are detrimental to the stability of dimethyl sulfate are not required when using aminophenazone, and the aliphatic quaternary ammonium salt product is more stable, with good stability, low interference, good ionization properties, and high response. The separation was performed on a Waters Atlantis HILIC C18 column (100 mm×2.1 mm, 3.0 µm) using a mobile phase consisting of 10 mmol/L ammonium acetate solution-0.1% formic acid methanol solution (50∶50, v/v) at a flow rate of 0.3 mL/min. The column temperature was set at 40 ℃, and the sample size was 1 µL. Dimethyl sulfate was determined in the electrospray positive ionization (ESI+) and multiple reaction monitoring (MRM) modes. Dimethyl sulfate showed good linear relationships within the range of 0.9935 to 7.9480 ng/mL (r=0.9997). The limit of detection and limit of quantification for dimethyl sulfate were 0.50 ng/mL and 1.15 ng/mL, respectively. The recoveries (n=3)of dimethyl sulfate were 94.9% to 106.4%. The relative standard deviations (RSDs) were 1.44% to 5.51%. The RSD of the methylated aminophenazone peak area was 4.32%, indicating good stability of the reaction product. Dimethyl sulfate genotoxic impurities were not detected in 9 batches of aminophenazone, caffeine, and tegafur samples, which indicated that the drug manufacturers paid attention to the control of these impurities. The proposed method is advantageous over the existing techniques in terms of the better ion peak shape and higher molecular weight, without interference from other fragments. The method is specific, sensitive, simple, rapid, and accurate, and it can be used for the determination of dimethyl sulfate genotoxic impurities in aminophenazone and other medicines.

4-Dimethylaminoantipyrine as a Broad Electrochemical Indicator for Immunosensors Platform.

Here, we describe 4-dimethylaminoantipyrine (4-DMAA)-mediated interfacing as a broad biochemical indicator to stabilize and promote the higher response of electrodes for immunological detection. We hypothesized that the improved biological interactions of 4-DMAA with electrodes and biological samples may be due to the interaction properties of the benzene and pyrazole chemical groups with graphite and proteins, respectively. In order to demonstrate that 4-DMAA could be used as a general indicator in electrochemical immunoassays, we used peptides as probes for the diagnosis of four neglected tropical infectious diseases Tegumentary leishmaniasis, Visceral leishmaniasis, Strongyloidiasis, and Leprosy on commercial graphite screen-printed electrodes. 4-DMAA oxidation was used to indicate specific biological recognition between the epitope-based peptide and serum immunoglobulin G (IgG) from infected patients. We demonstrated that 4-DMAA should be incorporated into the electrodes prior to serum application, which avoids interference with its sensitivity and specificity. In addition, 4-DMAA oxidizes at a low anodic potential, and the oxidation peak is useful for detecting proteins in biological fluids. In summary, we have successfully demonstrated the broad application of 4-DMAA as a general indicator for the specific diagnosis of four infectious diseases in electrochemical immunosensors. Such a strategy is quite advantageous for indirect detection of proteins that lack electrochemical activities or are spatially inaccessible on the electrode surface. This new indicator opens a new avenue for monitoring biological recognition, especially for immunosensors.

Oxidation of pyrazolone pharmaceuticals by peracetic acid: Kinetics, mechanism and genetic toxicity variations.

Peracetic acid (PAA) oxidation is an emerging technology in water disinfection and purification. This study evaluated the oxidation of three pyrazolone pharmaceuticals (i.e., Aminopyrine (AMP), Antipyrine (ANT), and Isopropylphenazone (PRP) by PAA. Experimental results showed that PAA exhibited structure selectivity to the above three pharmaceuticals and oxidized AMP with the highest reactivity. The degradation kinetics of AMP was investigated by calculating the apparent second-order rate constants (kapp) under different initial pH. Through kinetic simulation, the second-order rate constants of elementary reactions between AMP (i.e., neutral (AMP0) and protonated (AMP+) species) with PAA (i.e., neutral (PAA0) and anionic (PAA-) species) were obtained to be 0.34 ± 0.077 M-1 s-1(k"AMP+, PAA0), 0.89 ± 0.091 M-1 s-1(k"AMP0, PAA-) and 5.94 ± 0.142 M-1 s-1(k"AMP0, PAA0), respectively. The PAA could oxidize AMP via electrophilic attack, and the degradation site of AMP was confirmed to be the central nitrogen of -N(CH3)2 with the highest relative electrophilicity (sk-/sk+, 48.8614) by Density Functional Theory (DFT) calculation. The intermediates/products of AMP degradation were identified by high-performance liquid chromatography-mass spectrometry (LC-MS/MS), and the transformation pathways of AMP during PAA oxidation were inferred to be hydroxylation, demethylation, and CC cleavage. The genetic toxicity of AMP contaminated water could be reduced after PAA oxidation, which was evaluated by the micronucleus test of Vicia faba root tips.

Understanding the enzymatic inhibition of intestinal alkaline phosphatase by aminophenazone-derived aryl thioureas with aided computational molecular dynamics simulations: synthesis, characterization, SAR and kinetic profiling.

The work presented in this paper aims toward the synthesis of aryl thiourea derivatives 4a-l of pyrazole based nonsteroidal anti-inflammatory drug named 4-aminophenazone, as potential inhibitors of intestinal alkaline phosphatase enzyme. The screening of synthesized target compounds 4a-l for unraveling the anti-inflammatory potential against calf intestinal alkaline phosphatase gives rise to lead member 4c possessing IC50 value 0.420 ± 0.012 µM, many folds better than reference standard used (KH2PO4 IC50 = 2.8 ± 0.06 µM and L-phenylalanine IC50 = 100 ± 3.1 µM). SAR for unfolding the active site binding pocket interaction along with the mode of enzyme inhibition based on kinetic studies is carried out which showed non-competitive binding mode. The enzyme inhibition studies were further supplemented by molecular dynamic simulations for predicting the protein behavior against active inhibitors 4c and 4g during docking analysis. The preliminary toxicity of the synthesized compounds was determined by using brine shrimp assay. This work also includes detailed biochemical analysis along with RO5 parameters for all the newly synthesized drug derivatives 4a-l.