Objective:To analyze the accuracy of lung ultrasound and chest X-ray in the diagnosis of neonatal pulmonary disease.Methods:We prospectively collected newborns that needed chest X-ray examination to diagnose pulmonary disease from twelve neonatal intensive care units across the country between June 2019 and April 2020.Each newborn was examined by lung ultrasound within two hours after chest X-ray examination.All chest X-ray and lung ultrasound images were independently read by a radiologist and a sonographer.When there was a disagreement, a panel of two experienced physicians made a final diagnosis based on the clinical history, chest X-ray and lung ultrasound images.Results:A total of 1 100 newborns were enrolled in our study.The diagnostic agreement between chest X-ray and lung ultrasound(Cohen′s kappa coefficient=0.347) was fair.Lung ultrasound(area under the curve=0.778; 95% CI 0.753-0.803) performed significantly better than chest X-ray(area under the curve=0.513; 95% CI 0.483-0.543) in the diagnosis of transient tachypnea of the newborn( P<0.001). The accuracy of lung ultrasound in diagnosing neonatal respiratory distress syndrome, meconium aspiration syndrome, pneumonia and neonatal pulmonary atelectasis was similar to that of chest X-ray. Conclusion:Lung ultrasound, as a low-cost, simple and radiation-free auxiliary examination method, has a diagnostic accuracy close to or even better than that of chest X-ray, which may replace chest X-ray in the diagnosis of some neonatal lung diseases.It should be noted that both chest X-ray and lung ultrasound can only be used as auxiliary means for the diagnosis of lung diseases, and it is necessary to combine imaging with the clinical history and presentation.

In recent years, with the rapid development of life sciences, the use of laboratory fish in toxicology, genetics, developmental biology and medicine has increased dramatically, and they have gradually become important new model organisms. At the same time, the welfare of laboratory fish has also received increasing attention. Although the research level of experimental fish welfare is still in a relatively early stage compared to terrestrial experimental animals, developed regions such as Europe and America have established corresponding legal frameworks to safeguard the welfare of laboratory fish in research. This article elucidates the current developmental status of laboratory fish welfare, discusses the rationale behind the imperative to prioritize and enhance their welfare, deeply investigates factors influencing their welfare from the feeding stage and experimental stage. Moreover, it explores strategies for augmenting welfare standards, with the overarching aim of propelling the continual improvement of laboratory fish welfare in our country.

ObjectiveTo observe the fine structure of the trunk kidney in zebrafish, and to identify its secreted exosomes. MethodsThe microstructure and ultrastructure of the trunk kidney in zebrafish were observed by light microscopy and electron microscopy, and the particle size of exosomes was detected by nanoparticle tracking analysis (NTA). ResultsThe trunk kidney was close and parallel to the spine in adult zebrafish. The nephron consisted of renal tubules and renal corpuscles. The renal tubules could be further divided into three types: proximal convoluted tubules, distal convoluted tubules, and cervical segments. The renal corpuscles were composed of glomerulus and renal capsules. The periodic acid-Schiff (PAS) staining results revealed that there were abundant glycogen granules in the proximal convoluted tubules, with brush-like outline in the apical surface of epithelial cells. Under transmission electron microscopy (TEM), there were exosomes distributed in the lumen of renal tubules, with numerous late endosomes and few number of multivesicular bodies (MVBs) in the cytoplasm of the epithelial cells concentrating on the apical side. Meanwhile, MVBs were also distributed in the apical regions of the renal tubules and the podocytes of the renal glomeruli. Immunohistochemical staining results showed that CD9, CD63 and TSG101 were strongly expressed in the lumen surface of the renal tubules, but weakly expressed in the corpuscles and lumen. NTA and TEM results showed that the exosomes isolated from zebrafish trunk kidney were saucer-like outline, and the particle size mode was 144.4 nm, which was consistent with the characteristics of morphological futures of exosome. ConclusionThe zebrafish somatic kidney has the typical structure of the mammalian kidney and is the urinary organ in the body. The renal tubules have the ability to secrete exosomes, and their formation is a process of releasing poly-vesicles to the free surface of epithelial cells into the extracellular space. This study laid a morphological foundation for further study of exosomes in urinary function in aquatic experimental animals as well as the development and application of related models.

Objective:To study clinical pathological characteristics, immunohistochemical, molecular genetical changes and prognosis in pediatric eosinophilic solid and cystic renal cell carcinoma (ESC RCC) with TSC2 gene mutations.Methods:The tissue samples were collected from two pediatric ESC RCC patients between 2017 and 2018. The tissues were subjected to histological examination and immunohistochemistry using EnVision system. The TFE3, TFEB gene rearrangements were tested using FISH and molecular genetic study. The paraffin sections were used for DNA extraction, PCR amplification and NGS sequencing.Results:The two patients with ESC RCC were both male, aged at 9 years and 8 months, and 13 years, respectively. The tumors were from the right kidney, 5 cm and 7 cm in size, respectively, with solid and cystic changes in cross section, and grey-reddish or grey-whitish fish meat appearance. Microscopic observation revealed the tumors had fibrous capsules, which were infiltrated by the tumor cells. The tumor cells were diffusely distributed, round-shaped, or polygon-shaped, and had voluminous cytoplasm, eosinophilic cytoplasm, various sizes of vacuoles and clear cell-like appearance. There were papillary structures in some areas, with visible fiber septa. The nuclei were round and vesicular, with multi-nucleated cells and megakaryocytes. The mitoses were not seen. A few cystic structures were visible in different sizes, and capsule walls were covered with a single layer of spike-like tumor cells. Thick-walled blood vessels were seen in the stroma, with focal lymphocytic infiltration, eosinophilic necrosis, calcifications and cholesterol crystals. Immunohistochemistry of the tumor cells was positive for PAX8 (diffuse), CK20 (focal), CKpan (focal), CK10 (1 focal, 1 diffuse), INI1, vimentin, CD68, and Ki-67 (5%~10%); the tumor cells were negative for HMB45, S-100, Melan A, p53, desmin, TFE3, CK7, CK19, EMA, CD56, CgA, Syn, CD30, CD117, WT1 and SMA. Molecular genetic study showed that TFE3 and TFEB gene rearrangements were not detected by FISH. NGS sequencing showed TSC2 p.Lys574Ter (0.198) was found in patient one and TSC2 p.Arg406Ter (0.355) in patient two.Conclusions:ESC RCC in children is a rare disease, and can be misdiagnosed easily. It has unique pathological characteristics, and immunohistochemical, molecular and genetic changes. The prognosis is relatively good.

Objective:To assess the risk of COVID-19 foreign imports cases to China.Methods:We collected epidemic data (cumulative daily confirmed cases in each country, cumulative confirmed imported cases), demographic data (population density, population) and information on potential source groups of tourists (the daily estimated number of overseas Chinese, overseas Chinese students, overseas workers, foreign students coming to China and flight passengers) and the global health security index (GHS) to assess and predict risk of imported cases for recent (February 1 st to April 25 th) and future (after April 26 th). Results:Strong positive correlation was found among variables including the number of imported cases, cumulative confirmed cases, attack rate, number of overseas Chinese, number of overseas Chinese students, number of foreign students coming to China, number of flight passengers and GHS. In the recent risk analysis, imported cases of Russian were the highest, followed by United Kingdom, United States, France and Spain. In the future risk prediction, 44 countries including United States and Singapore are evaluated as potential high-risk countries in the future through the attack rate index of each country and the estimated average number of daily passengers.Conclusion:The risk assessment of COVID-19 imported cases can be used to identify high-risk areas in recent and future, and might be helpful to strengthen the prevention and control of the epidemic and ultimately overcome the epidemic.

Objective:To infer the start time of the resurgent COVID-19 epidemic in Xinfadi wholesale market in Beijing in June 2020 and evaluate the effect of comprehensive prevention and control measures in this epidemic.Methods:SEIR dynamics model was used to fit daily onset infections to search the start date of this resurgent COVID-19 epidemic in Beijing. The number of cumulative infections from June 12 to July 1 in Beijing were fitted considering different levels of control strength.Results:The current reemerged COVID-19 epidemic in Beijing probably started between May 22 and May 28 (cumulative probability: 95 %), with the highest probability on May 25 (23 %). The R0 of the current reemerged COVID-19 epidemic was 4.22 (95 %CI: 2.88-7.02). Dynamic model fitting suggested that by June 11, the cumulative number of COVID-19 cases would reached 99 (95 %CI: 77-121), which was in line with the actual situation, and without control, by July 1, the cumulative number of COVID-19 cases would reach 65 090 (95 %CI: 39 068-105 037). Since June 12, comprehensive prevention and control measures have been implemented in Beijing, as of July 1, compared with uncontrolled situation, the number of infections had been reduced by 99 %, similar to the fitting result of a 95 % reduction of the transmission rate. The sensitivity analysis showed consistent results. Conclusions:For the emergent outbreak of COVID-19, the dynamics model can be used to infer the start time of the transmission and help tracing the source of epidemic. The comprehensive prevention and control measures taken in Beijing have quickly blocked over 95 % of the transmission routes and reduced 99 % of the infections, containing the sudden epidemic timely and effectively, which have value in guiding the prevention and control of the epidemic in the future.

Recent years, national laws and government policies were published as series to encourage the development of group standardizations. The updated Standardization Law of the People's Republic of China, implemented on January 1^st, 2018, stipulates that group standard is a part of the Chinese standard system. Under the current supportive circumstances, more institutes and organizations have joined in the writing and releasing procedures of group standards’. Despite the rapid development of group standardization to publish, we are still at the phase of exploring and regulating group standardizations. This review summarizes the development and practice on the development group standardization in the Chinese Preventive Medicine Association and analyzes current condition and deficiency of the work in China, in order to develop suggestions and strategies to improve and regulate group standardization.

Discordance, such as overlap, repetition and inconsistent, of standards is one of the major problems in current standardization affair in China. Therefore, improving the unity and authority of standards through reduction of overlap, repetition and inconsistency has become the main goal of deepening standardization reform in China. This paper summarizes the discordance in public health standards in China, analyzes the major reasons and provides specific strategic suggestions through case analysis of public health standards in the ways of comparisons of same kind standards of other deparments and standards in administration documents and guidelines or technical specifications of academic associations or societies.

Objective To explore the clinical features and risk factors of poor prognosis in neonatal necrotizing enterocolitis(NEC).Methods A retrospective study was carried out in the infants with NEC admitted to 6 cooperative hospitals in Guangdong Province between January 2005 and December 2014.The clinical features and risk factors of poor prognosis in preterm and full-term infants diagnosed NEC,early onset and late onset NEC were analyzed.Results A total of 449 cases who met the criteria were admitted during the study time.The mortality was 23.6％ (106/449 cases),of which the preterm group was 24.6％ (58/238 cases) while the full-term group was 22.7％ (48/211 cases),the early onset group was 22.1％ (45/204 cases) while the late onset group was 24.3％ (57/235 cases).The median number of NEC onset in preterm group was 11 d after birth while the number of the full-term group was 6 d.Full-term infants who diagnosed NEC were more likely to manifest themselves as abdominal distension (52.1％ vs.42.0％,x2 =4.597,P =0.032),vomiting(36.5％ vs.17.2％,x2 =21.428,P =0.000) and bloody stool(30.3％ vs.21.4％,x2 =4.653,P =0.031);but in the onset of NEC,preterm infants more likely to have feeding intolerance (21.0％ vs.12.8％,x2=5.309,P =0.021).The early onset group of full-term NEC was much common in twins or multiplets(9.4％ vs.1.1％,x2 =6.226,P =0.013),which rate of surgical therapy was much higher (41.0％ vs.27.0％,P =0.036) and the breast-feeding rate before NEC was lower than the late onset group(14.5％ vs.32.6％,x2 =9.500,P =0.002),the differences were statistically significant.The gestational age and birth weight were bigger in the early onset group of preterm NEC[(33.8 ±2.5) weeks vs.(32.2 ±2.8) weeks,t =4.261,P =0.000;(2.1 ±0.5) kg vs.(1.7 ± 0.5) kg,t =4.735,P =0.000)],but length of stay was shorter than the late onset group (18.0 d vs.26.5 d,P =0.000).Logistic regression analysis showed that the risk factors of poor prognosis of full-term NEC were shock,peritonitis and sepsis;while risk factors of poor prognosis of preterm NEC were small for gestational age infant,pulmonary hemorrhage,shock,intestinal perforation and sepsis;the risk factors of poor prognosis of the early onset group of full-term NEC was shock;while those of the late onset group were shock and peritonitis;the risk factors of poor prognosis in the early onset group of preterm NEC were shock and sepsis,while those in the late onset group were pulmonary hemorrhage,shock,intestinal perforation and sepsis.Conclusions Compared to the preterm NEC,the onset time of full-term NEC was earlier and the clinical manifestations were more typical.Early identification and management of shock,peritonitis,intestinal perforation,sepsis and pulmonary hemorrhage can reduce the risk of poor prognosis of neonate NEC.

Objective To compare the differences of bacterial distribution of intestinal flora in Microtus fortis living under laboratory feeding and wild survival conditions. Methods The 16S rDNA-V4-V5 region of bacteria in the ileocecal contents from Microtus fortis raised in lab and captured in wild were measured by high-throughput sequencing. The number of operational taxonomic units(OTUs)were sorted and calculated,and the species abundance and distribution and difference were analyzed. Results The rarefaction curves indicated that adequate sampling was achieved. At the phylum level,the distribution of intestinal flora between two groups was similar. The experimental group had a unique phylum, Lentisphaerae. The wild type group had 3 unique phylums,Fusobacteria,Thaumarchaeota and an unclassified phylum. At the genus level, the kind of intestinal flora in the wild type group was more abundant than the experimental group. Ruminococcus is the largest differential genus. Conclusions The microbial community structure and differences of Microtus fortis living under different conditions are obtained. It may further enrich the basic biology data of Microtus fortis.