Total-body PET/CT, with its long axial field of view and high sensitivity detector, has shown potential for reducing the dose of radiopharmaceuticals. However, pediatric patients are significantly more sensitive to radiation and have a higher long-term cancer risk than adults, posing fundamental challenges for dose management in PET/CT examinations for these patients. In this article, the technical characteristics of total-body PET/CT and its radiation exposure status in children were systematically analyzed. The radiation exposure could be controlled by the following optimization strategies: adjusting the CT exposure parameters, optimizing the scanning mode, adding reconstruction algorithm, and reducing the injected dose of radioactive tracer. By addressing both external and internal radiation during the PET/CT scanning process, the overall radiation dose received by pediatric patients can be reduced within a certain range. In addition, this article also discusses the technical differences between “total-body” and “whole-body” concepts, and emphasizes that the future optimization of radiation dose in pediatric PET/CT should be realized by integration of personalized scanning protocols. Through reasonable management of scanning protocols and processes, low-dose and high-quality PET/CT imaging can be achieved in clinical environments, thus maximizing protection of pediatric patient health while minimizing the risks associated with ionizing radiation exposure.

Objective:To understand the genome-wide sequence variation and molecular evolution of coxsackievirus A4 (CV-A4) strain in Anhui province, so as to provide a theoretical basis for the pathogenic monitoring and scientific prevention and treatment of hand, foot and mouth disease in the future.Methods:Five CVA4 isolates of 2020 were sequenced by first-generation sequencing method. MEGA11.0 was used to construct a phylogenetic tree based on VP1 region for 5 CV-A4 isolates, 32 CV-A4 strains and Enterovirus A71(EV-A71) prototype strain BrCr, and the isolates and enterovirus A (EV-A) prototype strains based on P1, P2 and P3 regions respectively, and DNAStar was used for amino acid sequence comparison in VP1 region. BioEdit7.2 was used for amino acid displacement entropy analysis and amino acid site entropy mapping. SimPlot3.5 and RDP4 were used for recombination analysis of CV-A4 isolate and EV-A prototype representative strains, and DnaSP6 software was used for selection pressure analysis of isolates and reference representative strains.Results:The phylogenetic tree showed that the isolates belonged to the C2 subtype, which belonged to the same clade as the CV-A4 strain circulating in Chinese mainland, and the amino acid sequence homology of the C2 subtype branch was 97.3%-100%, and the isolates had 6 amino acid variation sites compared with the prototype. The selection pressure analysis showed that the CV-A4 strain of the C2 subtype was affected by negative selection pressure, and there were 25 mutagenic sites in the amino acid sequence in the coding region of the displacement entropy analysis, accounting for 1.14%, and the evolution of the strain mainly depended on recombination. Recombination analysis showed that the isolates recombined with a variety of EV-A prototype strains in the P2 and P3 regions, and the recombination section with the CV-A5 prototype strain was longer, especially in the 3A-3C section, and P1 was a relatively conserved region.Conclusions:CV-A4 has frequent recombination events with other EV-A prototype strains in P2 and P3, and the molecular evolution of CV-A4 in Anhui should continue to be closely monitored.

Hearing loss is one of the most common neurosensory disorders in humans,severely affecting pa-tients'quality of life with lack of ideal treatments.Its pathogenesis is related to oxidative stress,inflammation and apoptosis in the inner ear.Recent studies have demonstrated that members of the signal transducer and activator of transcriptions(STATs)family are involved in regulating gene expression in auditory cells during inner ear develop-ment and physiological activities such as apoptosis,oxidative stress,inflammation and autophagy during auditory disorders.In this paper,we review the research on STATs in inner ear development and hearing loss,and elucidate their specific molecular mechanisms,aiming to provide theoretical guidance and direction for the prevention and treatment of hearing loss.

Due to multiple factors such as the closed research and development (R&D) system and differences in international mainstream regulatory standards, the internationalization of Chinese patent medicines has been weakly promoted. Multi-case analysis based on grounded theory can identify the key factors that promote the internationalization of Chinese patent medicines in each link, so as to put forward suggestions for promoting the internationalization of Chinese patent medicines. By retrieving the research literature on the internationalization of Chinese patent medicines included in CNKI, and further searching the official websites of the corresponding enterprises, as well as the news reports, comments and analysis of related events on official websites such as Xinhua News Agency, People's Network and China Medical Device Network, 27 textual materials were obtained, 6 classic cases of international registration of Chinese patent medicines were summarized, and three-level coding was used to organize and analyze them level by level. 25 initial categories and 7 main categories were extracted, and 4 core categories were finally summarized: promote R&D and promotion in advantageous areas based on international needs, build a quality control system in line with the international standards, select appropriate national markets based on international demand, and carry out international collaborative R&D in the whole life cycle. Based on this, suggestions were put forward: in order to promote the internationalization process of Chinese patent medicines, priority disease types and product formulations should be determined based on demand during the drug discovery phase; full cycle international cooperation in drug R&D should be carried out; a Chinese patent medicines and simple preparations supervision system that is in line with the international standards in the link of drug quality supervision should be constructed; countries with flexible and experienced regulatory rules in the drug approval and marketing process should be chosen.

Vascular dementia (VaD) is the second commonest type of dementia which lacks of efficient treatments currently. Neuroinflammation as a prominent pathological feature of VaD, is highly involved in the development of VaD. In order to verify the therapeutic potential of PDE1 inhibitors against VaD, the anti-neuroinflammation, memory and cognitive improvement were evaluated in vitro and in vivo by a potent and selective PDE1 inhibitor 4a. Also, the mechanism of 4a in ameliorating neuroinflammation and VaD was systematically explored. Furthermore, to optimize the drug-like properties of 4a, especially for metabolic stability, 15 derivatives were designed and synthesized. As a result, candidate 5f, with a potent IC₅₀ value of 4.5 nmol/L against PDE1C, high selectivity over PDEs, and remarkable metabolic stability, efficiently ameliorated neuron degeneration, cognition and memory impairment in VaD mice model by suppressing NF-κB transcription regulation and activating cAMP/CREB axis. These results further identified PDE1 inhibition could serve as a new therapeutic strategy for treatment of VaD.

Our previous study demonstrated that phosphodiesterase 8 (PDE8) could work as a potential target for vascular dementia (VaD) using a chemical probe 3a. However, compound 3a is a chiral compound which was obtained by chiral resolution on HPLC, restricting its usage in clinic. Herein, a series of non-chiral 9-benzyl-2-chloro-adenine derivatives were discovered as novel PDE8 inhibitors. Lead 15 exhibited potent inhibitory activity against PDE8A (IC₅₀ = 11 nmol/L), high selectivity over other PDEs, and remarkable drug-like properties (worthy to mention is that its bioavailability was up to 100%). Oral administration of 15 significantly improved the cAMP level of the right brain and exhibited dose-dependent effects on cognitive improvement in a VaD mouse model. Notably, the X-ray crystal structure of the PDE8A-15 complex showed that the potent affinity and high selectivity of 15 might come from the distinctive interactions with H-pocket including T-shaped π-π interactions with Phe785 as well as a unique H-bond network, which have never been observed in other PDE-inhibitor complex before, providing new strategies for the further rational design of novel selective inhibitors against PDE8.

Objective:To analyze the salary level, change trend and salary satisfaction of nurses in tertiary public hospitals in China.Methods:The data was derived from three round third-party evaluation of the China Healthcare Improvement Initiative at 136 tertiary public hospitals from December 2017 to January 2018, March 2019 and January to March 2021. The self-reported salary, expected salary and salary satisfaction rate of nurses were analyzed.Results:The sample sizes of the three evaluations were 27 575, 27 568 and 25 197, representing the salary situation in 2017, 2018 and 2020 respectively. In 2017, 2018 and 2020, the actual average annual salary of nurses was 81 600 yuan, 100 000 yuan and 110 000 yuan respectively, the expected average annual salary was 140 000 yuan, 160 000 yuan and 160 000 yuan respectively, and the ratio of expected salary to actual salary was 1.72, 1.60 and 1.45 respectively. In 2017, 2018 and 2020, the proportion of nurses satisfied with their current income was 34.0%, 33.7% and 43.6% respectively. In 2020, nurses in the eastern region, other specialized hospitals, senior professional titles and graduate degrees had highest annual salary.Conclusions:The salary level and satisfaction rate of nurses in tertiary public hospitals in China show a slow growth trend, and the gap between actual salary and expected salary is gradually narrowing.

Optimization efforts were devoted to discover novel PDE10A inhibitors in order to improve solubility and pharmacokinetics properties for a long-term therapy against pulmonary arterial hypertension (PAH) starting from the previously synthesized inhibitor

Objective: To carry out the 4^th round of third-party evaluation on the implementation and effect of the 1^st year of the 2^nd Phase National Healthcare Improvement Initiative(abbreviated as Initiative)since 2015. Methods: The 4^th round of the evaluation survey adopted the same methods, organization and execution, and technical roadmap as the former three rounds of evaluations. Results: The 4^th round of evaluation was carried out from 18 March to 9 April, 2019 at 185 public hospitals in 31 provinces(autonomous regions, municipalities directly under the Central Government)and Xinjiang Production and Construction Corps.Facility survey, health professional survey and patient survey were conducted at each of the sample health facilities. A total of 120 782 valid questionnaires were collected from 144 non-psychiatric health facilities, 16 246 valid questionnaires were obtained from 41 psychiatric health facilities, and 252 cases of outstanding departments/hospitals in healthcare improvement were also collected. The average overall scoring of the 12 dimensions to assess Initiative implementation at 144 non-psychiatric health facilities was 84.4%. The overall outpatient satisfaction scoring was 91.1%, 96.7%for the inpatients. The overall inpatient satisfaction(family members inclusive) at 41 psychiatric health facilities was 93%. Areas remaining to be improved include day-surgery, telemedicine and medical social work. Compared with technical services, non-technical care should be further strengthened. The compensation, workload and work environment of the healthcare providers are still to be improved. Conclusions The implementation of the Initiative by health facilities has been greatly improved. The percentage of health facilities and patients who had positive perceptions of improved doctor-patient relationship has been increasing. Patient care experiences at public hospitals have been generally improved, and the implementation of promoting traditional Chinese Medicine practices also made progress. However, work satisfaction of healthcare providers was found to be rather low, compared to the high level of patient satisfaction.

Objective: To establish comprehensive understanding of the self-rated health of the Chinese doctors and nurses and probe into their influencing factors. Methods: Data were drawn from a hospital performance survey, which was conducted by the Peking Union School of Public Health from March 18th to April 9th, 2019, among the 144 tertiary public hospitals in 31 provinces, autonomous regions, and municipalities. The survey included a cell-phone based questionnaire filled out by the sampled doctors and nurses, in which they were asked to rate their health using a 5-level Likert scale(from " very poor" to " very good" ). Mann-Whitney U test was used to analyze the differences in self-rated health between doctors and nurses. Chi-square test and two-class multivariate logistic regression were performed to analyze factors affecting self-rated health of the providers. Results: Among the 144 sample hospitals, the proportion of doctors, who rated their health as " healthy" , was 20.30%(4 979/24 529), that of nurses was 28.92%(8 361/28 910). It was worse than that in some developed countries and lower than the general population in China. Multi-variate analysis showed that adequate sleeping time, satisfaction with the work and with the doctor-patient relationship, were positively associated with the level of self-rated health of the sampled doctors and nurses(P<0.05). It was also found that the longer the average weekly working time, the higher the recognition of " the work load is too heavy" , the lower the proportion of doctors and nurses who rated their health as " healthy" (P<0.05). Conclusions Sleep time, job satisfaction, workload and doctor-patient relationship are important factors affecting self-rated health of the Chinese doctors and nurses.