[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.

[Silencing PBX1 expression induces apoptosis and ROS production of lung cancer cells].

Objective: To investigate the effects of pre-B lymphocytic leukemia transcription factor (PBX1) expression on the apoptosis, reactive oxygen species (ROS) content and transcriptional activation factor 3 (STAT3) signaling pathway of lung cancer cells. Methods: Real-time quantitative polymerase chain reaction was used to detect the expression level of PBX1 in lung cancer tissues and adjacent tissues. The correlation between PBX1 expression level and clinical pathological parameters of patients were analyzed. Western blot was used to detect the protein expression level of PBX1 in human lung cancer cell lines, including A549, SPC-A1, SK-MES-1 and H1299. A549 cells were transfected with blank control (blank group), negative control (NC group) or PBX1 small interfering RNA (siRNA group), respectively. The cells apoptosis and ROS content were detected by flow cytometry. The protein expression levels of PBX1, STAT3, phosphorylated STAT3 (p-STAT3), B cell lymphoma/leukemia-2 (Bcl-2) and survivin in each group were detected by western blot. Results: The expression level of PBX1 mRNA in lung cancer was (2.36±0.23), significantly higher than (1.02±0.15) in paracancerous tissues (P<0.05). The expression level of PBX1 was correlated with lung cancer differentiation, lymph node metastasis and TNM stage (P<0.05). The expression levels of PBX1 in human lung cancer cells A549, SPC-A1, SK-MES-1 and H1299 were (0.454±0.038), (0.403±0.034), (0.311±0.028) and (0.377±0.035), respectively, significantly higher than (0.041±0.007) of human normal lung cells MRC-5 (P<0.05). The expression level of PBX1 protein in A549 cells transfected with PBX1 siRNA was (0.082±0.010), significantly lower than (0.704±0.065) of the blank group (P<0.05). The apoptosis rate and ROS content of siPBX1 group were (30.78±3.64)% and (51.55±5.03), respectively, significantly higher than (3.92±0.27)% and (22.36±1.31) of blank group (P<0.05). The protein expressions of p-STAT3, Bcl-2 and survivin were (0.051±0.006), (0.202±0.018) and (0.068±0.008), respectively, significantly lower than (0.172±0.010), (0.425±0.041) and (0.196±0.021) of blank group (P<0.05). Conclusion: Inhibition of PBX1 expression can induce the apoptosis of lung cancer cell, the mechanism may be related to ROS production and down-regulation of STAT3 signal.

Plasma metabolite changes in dairy cows during parturition identified using untargeted metabolomics.

The metabolic responses of cows undergo substantial changes during the transition from late pregnancy to early lactation. However, the molecular mechanisms associated with these changes in physiological metabolism have not been clearly elucidated. The objective of this study was to investigate metabolic changes in transition cows from the perspective of plasma metabolites. Plasma samples collected from 24 multiparous dairy cows on approximately d 21 prepartum and immediately postpartum were analyzed using ultra-high-performance liquid chromatography/time-of-flight mass spectrometry in positive and negative ion modes. In conjunction with multidimensional statistical methods (principal component analysis and orthogonal partial least squares discriminant analysis), differences in plasma metabolites were identified using the t-test and fold change analysis. Sixty-seven differential metabolites were identified consisting of AA, lipids, saccharides, and nucleotides. The levels of 32 plasma metabolites were significantly higher and those of 35 metabolites significantly lower after parturition than on d 21 prepartum. Pathway analysis indicated that the metabolites that increased from late pregnancy to early lactation were primarily involved in lipid metabolism and energy metabolism, whereas decreased metabolites were related to AA metabolism.

[Clinical analysis of therapeutic bronchoscopy for tracheal neoplasm].

Objective: To analyze the clinical features in adults with tracheal neoplasm and to evaluate the efficacy of interventional bronchoscopic treatment. Methods: We retrospectively analyzed the clinical features of 43 adults undergoing therapeutic bronchoscopy for tracheal neoplasm diagnosed in Changhai Hospital affiliated to the Second Military Medical University from January 2004 to July 2014.The degree of stenosis, the grade of dyspnea, and Karnofsky performance status scale were evaluated before and after the last procedure. All cases were followed up for 2 years. Results: The 43 cases took (4.6±3.9) months on average to be diagnosed since initial symptom. The initial misdiagnosis rate was 41.9%(18/43), and 11 cases were mistaken for asthma (11/43). Malignant tumors were more common than benign tumors for tracheal neoplasm in adults. Squamous cell carcinoma and adenoid cystic carcinoma were the top 2 histological types. Central airway obstruction was completely or partially alleviated with significant relief of dyspnea after the procedures, and all 6 cases of tracheal benign tumors got complete alleviation (the overall response rate was 100%). The grade of dyspnea was 3.2±0.7 before and 1.5±0.8 after the procedures(t=6.63, P<0.05). The value of KPS was 63±12 before and 83±11 after the procedures(t=5.78, P<0.05). The 2-year survival rate of 6 cases of tracheal benign tumors was 100.0%, and 1 case of papillomatosis had a relapse. The 1-year survival rate and 2-year survival rate of 37 cases of tracheal malignant tumors were 59.5% and 43.2% respectively with a median survival of 13.6 months. Conclusion: Therapeutic bronchoscopic interventions provide significantly alleviation of central airway obstruction and result in improvement in shortness of breath and quality of life for tracheal neoplasm.

A multiplex PCR for simultaneous detection of classical swine fever virus, African swine fever virus, highly pathogenic porcine reproductive and respiratory syndrome virus, porcine reproductive and respiratory syndrome virus and pseudorabies in swines.

In this assay, we developed and evaluated a multiplex PCR (mPCR) for its ability in detecting multiple infections of swine simultaneously. Four pairs of primers were used to detect five viruses. Specific primers were designed for classical swine fever virus (CSFV), African swine fever virus (ASFV) and pseudorabies (PRV). A pair of primers was designed prudently for two different types of porcine reproductive and respiratory syndrome virus that respectively were porcine reproductive and respiratory syndrome virus (PRRSV), highly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV). The detection limits of the mPCR were 1.09 × 104, 1.50 × 10³, 2.10 × 10³, 1.30 × 10³ and 8.97 × 10² copies/reaction for CSFV, ASFV, HP-PRRSV, PRRSV and PRV, respectively. A total of 49 clinical specimens were tested by the mPCR, and the result showed that co-infection by two or three viruses was 51%. In conclusion, the PCR is a useful tool for clinical diagnosis of not only single infections but also mixed infections in swines.

A 90-day subchronic toxicity study of neem oil, a Azadirachta indica oil, in mice.

To determine the no-observed-adverse-effect level (NOAEL) of exposure and target organs of neem oil for establishing safety criteria for human exposure, the subchronic toxicity study with neem oil in mice was evaluated. The mice (10 per sex for each dose) was orally administered with neem oil with the doses of 0 (to serve as a control), 177, 533 and 1600 mg/kg/day for 90 days. After the treatment period, observation of reversibility or persistence of any toxic effects, mice were continuously fed without treatment for the following 30 days. During the two test periods, the serum biochemistry, organ weight and histopathology were examined. The results showed that the serum biochemistry and organ coefficient in experimental groups had no statistical difference compared with those of the control group. At the 90th day, the histopathological examinations showed that the 1600 mg/kg/day dose of neem oil had varying degrees of damage on each organ except heart, uterus and ovarian. After 30-day recovery, the degree of lesions to the tissues was lessened or even restored. The NOAEL of neem oil was 177 mg/kg/day for mice and the target organs of neem oil were determined to be testicle, liver and kidneys.

Isolated invasive Aspergillus tracheobronchitis: a clinical study of 19 cases.

Isolated invasive Aspergillus tracheobronchitis (iIATB) is an uncommon clinical form of invasive Aspergillosis in which Aspergillus infection is limited entirely or predominantly to the tracheobronchial tree. In the present study, we retrospectively analyzed the medical records of 19 patients who had histological documented iIATB in the Department of Respiratory Medicine of Changhai Hospital between October 2000 and February 2008. Malignancy was the most common underlying disease, which existed in 14 patients (73.7%) in our series. Most patients had impaired airway structures or defence functions, whereas the systemic immune status was relatively normal. Only three patients (15.8%) had neutropenia. The clinical manifestations and chest radiograph were nonspecific. We classified iIATB into four different forms according to the bronchoscopic features of intraluminal lesions: superficial infiltration type (Type I, n = 4), full-layer involvement type (Type II, n = 2), occlusion type (Type III, n = 6) and mixed type (Type IV, n = 7). Type IV was the largest group in our study, followed by Type III. All patients with iIATB of Type IV had definite airway occlusion. Fourteen patients (73.7%) had a good response to antifungal treatments and five (26.3%) died as a result of the progression of Aspergillosis, all of whom had full-layer invasion of the involved bronchi. In conclusion, we found that iIATB could occur in moderately or non-immunocompromised patients with impaired airway structures or defence functions and may be an early period of invasive pulmonary Aspergillosis. Most of the iIATB patients had a favourable prognosis with early diagnosis and effective antifungal treatment. The morphological features of intraluminal lesions might be of prognostic value.