Objective To study the neurotoxic effects of acute exposure of methylmercury at low dose and to provide some experimental data for deeply exploring the early mechanism of neurotoxicity of methylmercury. Methods SD rats were administered with methylmercury chloride by intraperitoneal injection with different doses of 0.05, 0.50 and 5.00 mg/kg and different exposure times of 20 min, 1 h, 4 h, 24 h. Mercury, ACh and AChE contents in rat brains were measured. Results Mercury contents in rat brains significantly increased after 20 min-exposure at both 0.50 and 5.00 mg/kg doses. Significant increase occurred after 4 h exposure at dose of 0.05 mg/kg. ACh and AChE in rat brains significantly changed after 20 min at every dose, showing certain dose-response and time-response relations. Conclusion Changes of ACh and AChE in rat brain after administration of low dose(0.05 mg/kg) and short time(20 min) exposure suggested certain modulation of CNS had been initiated. With the increases of exposure dose and time, methylmercury might begin to accumulate in rat brain and induce the significant changes of ACh and AChE.

Based on Moens-Korteweg model & hydrostatic principle, a simple calibration method by changing vertical distance between heart and radial artery is proposed in this paper. Using hydrostatic pressure to change arterial pressure and pulse wave transmit time, consequently obtain several sets of cardiovascular parameters and finally build up relationship between blood pressure and pulse wave transmit time. Clinical tests have been carried with different age and gender for long and short time monitoring. The comparison results with Sphygmomanometer OMRON EW3152 show its promising accuracy and coincidence feature in blood pressure measurement.
Blood Pressure Determination ; instrumentation ; methods ; Blood Pressure Monitors ; Calibration ; Equipment Design

[Objective] In view of the crucial role of indole propionic acid in the treatment of tumor immune checkpoint blockade and further revealing its mechanism, our study intended to design and synthesize 1-[¹⁸F]-fluoroethyl-indole propionic acid (1-[¹⁸F]-IPA), and evaluate it as a tumor PET imaging agent. [Methods] The precursor 1-(2-p-toluenesulfonic acid oxygen ethyl)-methyl indole propionate underwent nucleophilic substitution reaction with ¹⁸F^-. The crude product was separated and purified by high-performance liquid chromatography and the intermediates were collected. Finally, 1-[¹⁸F]-IPA was obtained by hydrolysis. The clarity of the product was measured by visual inspection, the pH value was determined by precision test paper, and the radiochemical purity and stability were determined by high-performance liquid chromatography. In order to determine the biodistribution of 1-[¹⁸F]-IPA in normal mice, ICR mice were intravenously injected with 1-[¹⁸F]-IPA (0.2 mL, 7 MBq), and sacrificed at 5, 15, 25, 45, 75 and 120 min and dissected. Micro-PET imaging was performed and analyzed in BxPC-3 tumor-bearing nude mice. Student t test was used to compare the biodistribution of tissues and organs at different time points. [Results] The total preparation time of 1-[¹⁸F]-IPA was 35-40 min, the radiochemical yield was (45±5)%, and the radiochemical purity was more than 95%. The product solution was clear without particles, and the pH value was 6.5, which had good stability in vitro and in vivo. The results of biodistribution in healthy ICR mice showed that except for the brain, 1-[¹⁸F]-IPA had a certain uptake in all major organs, with the most obvious uptake in the liver, gallbladder and kidneys. The radioactivity in the gallbladder gradually increased with time and reached (39.86±6.56)%ID/g at 120 min, but bone uptake did not change significantly with time. Micro-PET/CT showed that there was radioactive uptake at the tumor 30 min after injection of 1-[¹⁸F]-IPA in Dutch BxPC-3 nude mice, but it was not obvious. At this time, SUVmax was about 55.18±14.62. Consistent with the results of biodistribution, the brain uptake was low at each time point. [Conclusion] In summary, 1-[¹⁸F]-IPA with short preparation time and high yield is expected to be a tool to probe tryptophan indole metabolism pathway and further reveal tumor immune resistance.

【Objective】 To analyze the epidemiological characteristics of pertussis in Shaanxi Province from 2012 to 2021. 【Methods】 We collected the information of pertussis cases in Shaanxi Province from 2012 to 2021 by the China Disease Control and Prevention Information System for analyzing the incidence and distribution characteristics. 【Results】 From 2012 to 2021, a total of 8270 cases of pertussis were reported in Shaanxi Province, with the incidence ranging from 0.21 to 6.20 per 100 000 persons, and for an annual average incidence of 2.17 per 100 000 persons. 44.81% (3 706/8 270) occurred from June to September. The annual average incidence in southern Shaanxi, Guanzhong, and northern Shaanxi was 1.78, 2.47, and 1.46 per 100 000 persons (χ²=289.638, P<0.001). The number of patients (proportions) with pertussis aged 0-1, 1-5, 5-10, and ≥10 years was 3 884 (46.96%), 2 869 (34.69%), 1 408 (17.03%), and 109 (1.32%), respectively. The number of patients (proportion) ≤ 2 months old, 3-5 months old, and ≥ 6 months old was 884 (22.76%),1 608 (41.40%), and 1 392 (35.84%) among pertussis patients under 1 year old. 【Conclusion】 The incidence of pertussis in Shaanxi Province basically showed an increasing trend with higher rates between June and September, higher rates in Guanzhong region of the province, and more patients over 5 years old.