Objective:To determine the half lethal dose(LD50) of paraquat in rats and to establish a relatively safe and stable pathological animals model of pulmonary fibrosis.Methods: Ninety-six SD rats totally in half genders.Fifty SD rats in half genders were randomly divided into 5 groups,each had 10 rats.Feed the rats with different doses of liquor of paraquat intraperitoneally one time and definite the half lethal dose of one and two weeks.After that,prepare another forty-six SD rats,also in half genders,as intonication group,twenty-eight rats were treated with the liquor of paraquat in dosage of 18 mg/kg intraperitoneally.As control group,sixteen rats were treated with equivalent volume of normal saline.Observe the toxic symptom daily and rats were sacrificed on day 1,3,5,7,14,21,28,35 and 42 respectively for the histological examination.Results: The half lethal doses of intraperitoneal paraquat of 1 and 2 weeks were 18.27 and 17.29,with 95% confidence intervals of 16.61-20.09 and 15.99-18.67,respectively.After intraperitoneal paraquat injection at the dose of 18 mg/kg,typical toxic symptoms were observed at different times in the rats.The whole process of acute lung injury and fibrosis induced by paraquat intoxication could be seen with the naked eyes or under the light microscope.Conclusion: Paraquat has a strong toxicity to rats.A proper dose of paraquat solution can not only reduce the number of experimental rats,but also induce typical pulmonary fibrosis in rats.

Objective To investigate the epidemiology characteristics of crawfish related rhabdomyolysis (RM) in Nanjing, 2016.Methods Outpatient and inpatient electronic medical system of 21 hospitals in Nanjing during 2016 were retrospectively searched, and all the patients diagnosed with RM were selected. The patients with none crayfish-related RM was excluded. The epidemiology characteristics were depicted. The geographic information system (GIS) was used to collect, manage and analyze the spatial data, to visualize it, to analyze the spatial distribution features of the disease, and to explore the cause of disease prediction. GeoDa 1.8 software was used to analyze the global and local spatial auto-correlation.Results A total of 1183 patients with crawfish related RM were initially screened, excluding 59 patients with RM caused by trauma, severe exercise, heat stroke, myositis, poisoning, drugs, and genetic diseases, and 1124 patients were enrolled. The proportion of men was 36.48% (410/1124) with an incidence of 12.54/100 thousands; while of women was 63.52% (714/1124) with an incidence of 21.86/100 thousands. The median age at onset was 34 (28, 43) years. From July to August, the incidence of crawfish related RM was the highest, accounting for 96.53% of the total number of cases. The top four incidence areas were Pukou (41.54/100 thousands), Jianye (25.94/100 thousands), Qixia (25.73/100 thousands), Gulou (25.04/100 thousands), all of which were adjacent to the Yangtze River. Global spatial autocorrelation analysis showed: MoranI = 0.427,Z = 2.646,P = 0.003, suggesting that the crawfish related RM had positive spatial autocorrelation. The results showed that the spatial structure of crawfish related RM existed in Nanjing in 2016. Local spatial autocorrelation analysis showed that the high-high concentration areas were Pukou, Jianye and Liuhe. The incidences of above three areas which were the Nanjing section of the lower reaches of the Yangtze River flowed through the region and surrounding areas were higher than the overall incidence of Nanjing.Conclusion The prevalence of crawfish related RM in Nanjing during 2016 had an obvious region-concentrated character and global spatial autocorrelation with the high prevalent regions mainly concentrated in the urban areas adjacent to the Yangtze River.

AIM: To evaluate the performance of three distinct large language models(LLM), including GPT-3.5, GPT-4, and PaLM2, in responding to queries within the field of ophthalmology, and to compare their performance with three different levels of medical professionals: medical undergraduates, master of medicine, and attending physicians.METHODS: A total of 100 ophthalmic multiple-choice tests, which covered ophthalmic basic knowledge, clinical knowledge, ophthalmic examination and diagnostic methods, and treatment for ocular disease, were conducted on three different kinds of LLM and three different levels of medical professionals(9 undergraduates, 6 postgraduates and 3 attending physicians), respectively. The performance of LLM was comprehensively evaluated from the aspects of mean scores, consistency and confidence of response, and it was compared with human.RESULTS: Notably, each LLM surpassed the average performance of undergraduate medical students(GPT-4:56, GPT-3.5:42, PaLM2:47, undergraduate students:40). Specifically, performance of GPT-3.5 and PaLM2 was slightly lower than those of master's students(51), while GPT-4 exhibited a performance comparable to attending physicians(62). Furthermore, GPT-4 showed significantly higher response consistency and self-confidence compared with GPT-3.5 and PaLM2.CONCLUSION: LLM represented by GPT-4 performs well in the field of ophthalmology, and the LLM model can provide clinical decision-making and teaching aids for clinicians and medical education.

Precisely delivering combinational therapeutic agents has become a crucial challenge for anti-tumor treatment. In this study, a novel redox-responsive polymeric prodrug (molecular weight, MW: 93.5 kDa) was produced by reversible addition-fragmentation chain transfer (RAFT) polymerization. The amphiphilic block polymer-doxorubicin (DOX) prodrug was employed to deliver a hydrophobic photosensitizer (PS), chlorin e6 (Ce6), and the as-prepared nanoscale system [NPs(Ce6)] was investigated as a chemo-photodynamic anti-cancer agent. The glutathione (GSH)-cleavable disulfide bond was inserted into the backbone of the polymer for biodegradation inside tumor cells, and DOX conjugated onto the polymer with a disulfide bond was successfully released intracellularly. NPs(Ce6) released DOX and Ce6 with their original molecular structures and degraded into segments with low MWs of 41.2 kDa in the presence of GSH. NPs(Ce6) showed a chemo-photodynamic therapeutic effect to kill 4T1 murine breast cancer cells, which was confirmed from a collapsed cell morphology, a lifted level in the intracellular reactive oxygen species, a reduced viability and induced apoptosis. Moreover, ex vivo fluorescence images indicated that NPs(Ce6) retained in the tumor, and exhibited a remarkable in vivo anticancer efficacy. The combinational therapy showed a significantly increased tumor growth inhibition (TGI, 58.53%). Therefore, the redox-responsive, amphiphilic block polymeric prodrug could have a great potential as a chemo-photodynamic anti-cancer agent.