[Determination of triclocarban and triclosan in urine by QuEChERS extraction and ultra-performance liquid chromatography-tandem mass spectrometry].

Objective: To establish a method for the determination of triclocarban (TCC) and triclosan (TCS) in urine by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) after purification by QuEChERS. Methods: In May 2022, urine samples were extracted by acetonitrile, purified by QuEChERS, separated by Waters Acquity UPLC BEH C18 column (100 mm×2.1 mm, 1.7 µm), and eluated with water-acetonitrile as mobile phase gradient at a flow rate of 0.3 ml/min. The detection was conducted in negative ion mode (ESI(-)) and multiple reaction monitoring (MRM) scanning, it was quantified with a internal standard method, and the methodology was verified. Results: The linear ranges of TCC and TCS were 0.5-100.0 µg/L and 1.0-100.0 µg/L, and the correlation coefficients were 0.9997 and 0.9991, respectively. The limits of detection and quantitation of TCC and TCS were 0.17 and 0.33 µg/L, and 0.5 and 1.0 µg/L, respectively. The recoveries of TCC and TCS were 100.1%-102.8% and 96.7%-108.6%, and the relative standard deviations were 4.9%-6.7% and 4.1%-8.3%, respectively, at 2.0, 10.0 and 80.0 µg/L. Conclusion: QuEChERS-UPLC-MS/MS method is simple, rapid, sensitive and reproducible, and can be used for rapid and accurate simultaneous detection of TCC and TCS exposure levels in occupational population.

[One case of extensive high-pressure injection injury of hand caused by polyurethane material].

This article reports a patient with extensive high-pressure injection injury of the hand caused by mistaken injection of polyurethane material into the index finger, who was diagnosed and treated in the Department of Orthopedics of Huzhou Central Hospital in 2019. Both the digital artery and digital nerve were involved, and the polyurethane involved the right palm along the flexor tendon sheath of the index finger and wrist. Due to the lack of X-ray development, the scope of the first debridement was small, and the blood supply to the fingertip was poor. Finally, the patient's right index finger was amputated due to infection and necrosis. MR or B-ultrasound should be perfected before operation to clarify the extent of polyurethane involvement. The initial thorough debridement or multiple debridements are necessary to improve the prognosis. If the blood supply of the fingers is poor, the blood supply can be reconstructed by skin flap transplantation.

[Bilateral posterior shoulder dislocation with associated reverse Hill-Sachs lesions after electrical injury].

After workers suffer electric shock, the ankylosis and contraction of muscle groups around the shoulder joint are more likely to lead to posterior dislocation and fracture, of which 80% are complicated with reverse Hill-Sachs injury of humeral head. This paper reports a case of bilateral posterior dislocation of shoulder joint combined with Hill-Sachs injury caused by electric shock in the Department of Orthopedics, Affiliated Huzhou Hospital, Zhejiang University School of Medicine in August 2020. The diagnosis of left posterior shoulder dislocation was clear, and the diagnosis of right posterior shoulder dislocation was missed. The patient successfully reconstructed the stability of the shoulder joint by actively performing shoulder arthroscopic surgery to repair the joint capsule. After 6 months of follow-up, there was no further dislocation and the function was good.

The pathology of selenium deficiency in Cyprinus carpio L.

Selenium is essential for the normal life processes, and all animals, including fish, need this inorganic element. In order to research the pathology of selenium deficiency in common carp, Cyprinus carpio L., 360 juvenile carp were allocated to three treatments. Each treatment containing 120 fish was randomly divided into four groups, fed with purified diets containing selenium at 0, 0.15, 0.30 and 0.45 mg kg(-1). The results indicated that the morbidity and mortality rates of the test groups were negatively correlated with the level of selenium in the diets. The morbidity and mortality rates were, respectively, 46.7%, 33.3%, 13.3%, 0 and 26.7% 16.7%, 6.7%, 0. The affected fish exhibited pathological changes, such as 'thin back disease' and lordosis. Histologically, there was no abnormality observed in muscles, liver and pancreas. Ultrastructurally, there was swelling of the mitochondria of the cardiac muscle cells, the liver cells and renal tubular epithelial cells, with disintegration and lysis of the cristae of the mitochondria which vesiculated. Serum glutamic oxaloacetic transaminase and glutamic pyruvic transaminase levels were increased and the activity of the serum glutathione peroxidase and the serum superoxide dismutase was decreased; in contrast, the serum malonaldehyde concentration was increased.

[Determination of cholesterol and alpha-tocopherol in eggs by capillary gas chromatography].

A simple and rapid method has been developed for simultaneous determination of cholesterol and alpha-tocopherol in eggs. The method involves alcoholic KOH saponification of the samples, extraction with petroleum ether, and determination by wide-bore capillary gas chromatography. The recoveries of cholesterol and alpha-VE in eggs were 91.0%-93.3% and 82.5%-95.0%, with RSDs of 2.7%-3.1% and 4.9%-6.9% respectively.

[Capillary gas chromatographic determination of residual benzene, toluene and DMF in acrylic fabrics].

A simple method for the analysis of residual benzene, toluene and N,N-dimethyl formamide (DMF) in acrylic fabrics by wide-bore capillary gas chromatography is presented. The sample was extracted by carbon disulfide (CS2) for an hour. The results showed that this is a rapid and sensitive method with less interferences and fairly good precision. The detection limits were 0.1, 0.1 and 2.0 ng for benzene, toluene and DMF respectively. The recoveries were 93.3%-101.8% and coefficients of variation were 2.0%-3.4%.