Objective To evaluate the acute toxicity and acute eye irritation of hydroquinone. Methods i) Acute toxicity test. Specific pathogen-free (SPF) Kunming mice were randomly divided into four dose groups, 10 mice per group with equal number of males and females. Hydroquinone was administered as a single exposure via oral gavage and intraperitoneal injection at doses of 0.00, 100.00, 250.00, and 500.00 mg/kg body weight. The mice were observed for 14 days. The toxic symptoms were recorded, and median lethal dose (LD₅₀) was calculated. ii) In vitro eye irritation test. Fertilized chicken embryos were randomly divided into four dose groups, with six embryos in each group. The chorioallantoic membrane (CAM) assay was used to evaluate the acute eye irritation potential of hydroquinone in vitro. iii) SPF Kunming mice were randomly divided into three doses groups, 10 mice per group with equal numbers of males and females. Hydroquinone was administered via tail vein injection at doses of 0.00, 25.00, and 50.00 mg/kg body weight. Blood alanine aminotransferase (ALT), aspartate aminotransferase (AST), methemoglobin (MetHb), and cholinesterase levels were measured using colorimetric methods after one hour exposure. Organ coefficients of the heart, liver, spleen, lungs, and kidneys in mice were calculated. Results i) Following oral administration of 500.00 mg/kg body weight hydroquinone, the mice rapidly developed severe toxic symptoms, including agitation, cyanosis of the lips, eye closure, and limb convulsions. Trunk rigidity and curling occurred within 15-60 mins, ended up with death. After intraperitoneal injection at 500.00 mg/kg body weight hydroquinone, toxic reactions occurred more rapidly, with all mice died within five mins. The LD₅₀ values for acute oral and intraperitoneal exposure were 356.64 and 275.90 mg/kg body weight, respectively. Female mice had higher LD₅₀ values for acute intraperitioneal exposure than males (316.58 vs 276.38 mg/kg body weight). ii) The in vitro eye irritation test results showed an irritation score of 3.05 at a dose of 100.00 mg/kg body weight, indicating mild eye irritation, accompanied by vascular congestion and edema in the embryos. iii) Tail vein injection results showed that mouse serum ALT activity increased with increasing hydroquinone doses (all P<0.05), and ALT activity was higher in males than in females (P<0.01). Serum AST activity of mice in the 25.00 and 50.00 mg/kg body weight groups was higher than that in the 0.00 mg/kg body weight group (both P<0.05). With increasing hydroquinone-exposed doses, whole bood MetHb levels increased and cholinesterase activity decreased in both male and female mice (both P<0.05). Male mice had higher MetHb levels than females at corresponding doses among 25.00 and 50.00 mg/kg body weight groups (all P<0.05). Serum cholinesterase levels in male mice were higher than that in females at corresponding doses among 0.00 and 25.00 mg/kg body weight groups (both P<0.05). As the hydroquinone exposure dose increased, the liver organ coefficients decreased in both female and male mice (both P<0.05). The liver organ coefficient in male mice at the 50.00 mg/kg body weight group was higher than that in female mice (P<0.05). Compared to mice of the same sex in the 25.00 mg/kg body weight group, the kidney organ coefficients decreased in both female and male mice in the 0.00 mg/kg body weight group (all P<0.05), and decreased in the 50.00 mg/kg body weight group (all P<0.05). The male mice had lower kidney organ coefficient than female mice at 25.00 mg/kg body weight group (P<0.05). Conclusion Hydroquinone is classified as a moderately toxic substance. Increasing exposure doses result in pronounced eye irritation and affect hepatic and renal functions of mice.

BACKGROUND: The lack of pathological quality control standard in detecting epidermal growth factor receptor (EGFR) gene mutation in malignant pleural effusion leads to confusion in the interpretation of detection results and the clinical use of EGFR-tyrosine kinase inhibitor (TKI). Therefore, it is very important to propose quality control standards and guide the detection of EGFR mutation in pleural effusion. The aim of this study is to retrospectively analyze the results of EGFR gene mutation in pleural effusion sediment section according to strict pathological quality control standards, and the therapeutic effect of EGFR-TKIs guided by this detection results. METHODS: From January 2012 to June 2018, the clinical data of patients with pleural effusion collected from Department of Pathology of Peking Union Medical College Hospital were analyzed retrospectively. Among them, 132 patients with relatively complete clinical data and with EGFR gene mutation detection of paraffin-embedded pleural effusion sediment section according to the established quality control standard were included. According to the results of EGFR gene mutation, it was divided into positive group and negative group, and the efficacy of EGFR-TKIs in different groups was compared. RESULTS: After the centrifugation of pleural effusion, the sediment was embedded in paraffin, sectioned, and observed under the microscope after HE staining. If the number of tumor cells ≥100, it met the pathological quality control standard, and it could be used for subsequent EGFR gene mutation detection. EGFR gene mutations were detected in 72 (54.5%) of 132 patients. EGFR-TKIs were used in 69 of 72 mutation positive patients. Of 60 EGFR mutation negative patients, only 15 used EGFR-TKIs. In EGFR mutation positive group, the disease control rate (DCR) was 95.8%, and the median progression-free survival (PFS) was 11 months. In EGFR mutation negative group, the DCR was 0%, and the median PFS was 1 month. The DCR and PFS were significantly different between the two groups (P<0.05). CONCLUSIONS According to the pathological quality control standards, the embedded section of pleural fluid sediment can be used to detect EGFR gene mutation, and the results can be used to guide the clinical use of EGFR-TKIs.

Objective To investigate the research quality of present medical graduates and propose suggestions for improvement.Method A self-designed questionnaire entitled Investigating Questionnaire for Research Quality Analysis of Medical Graduates in Peking Union Medical College Hospital was distributed to the clinical and academic medical graduates in the hospital from July to August 2015.Among 276 collected questionnaires,270 were validated as effective.SPSS 18.0 software was used to statistically describe the result and to perform t test on different subgroups.Results The research quality average of the surveyed hospital was 10.28.Results revealed that in regard of the three aspects of research quality,research consciousness ranked first,followed by the research ability,while scientific spirit was the weakest.Academic medical graduates showed significantly higher scores than clinical graduates in terms of total research quality and every single aspect (P values less than 0.05).Conclusions To better cultivate the academic leaders in medical research,it is necessary to strengthen the research training for the graduates,practice their scientific thinking especially the clinical graduates,reinforce tutors' guidance,and promote communication and collaboration.