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To investigate the effect of adipose-derived stem cells (ASCs) transplantation on radiation-induced lung injury (RILI), Sprague-Dawley rats were divided into phosphate-buffered saline (PBS) group, ASCs group, Radiation + PBS group, and Radiation + ASCs group. Radiation + PBS and Radiation + ASCs groups received single dose of 30 Gy X-ray radiation to the right chest. The Radiation + PBS group received 1 mL PBS suspension and Radiation + ASCs group received 1 mL PBS suspension containing 1 × 107 CM-Dil-labeled ASCs. The right lung tissue was collected on Days 30, 90, and 180 after radiation. Hematoxylin–eosin and Masson staining were performed to observe the pathological changes and collagen fiber content in the lung tissue. Immunohistochemistry (IHC) and western blot (WB) were used to detect levels of fibrotic markers collagen I (Collal), fibronectin (FN), as well as transforming growth factor-β1 (TGF-β1), p-Smad 3, and Smad 3. Compared with the non-radiation groups, the radiation groups showed lymphocyte infiltration on Day 30 after irradiation and thickened incomplete alveolar walls, collagen deposition, and fibroplasia on Days 90 and 180. ASCs relieved these changes on Day 180 (Masson staining, P = 0.0022). Compared with Radiation + PBS group, on Day 180 after irradiation, the Radiation + ASCs group showed that ASCs could significantly decrease the expressions of fibrosis markers Collal (IHC: P = 0.0022; WB: P = 0.0087) and FN (IHC: P = 0.0152; WB: P = 0.026) and inhibit the expressions of TGF-β1 (IHC: P = 0.026; WB: P = 0.0152) and p-Smad 3 (IHC: P = 0.0043; WB: P = 0.0087) in radiation-induced injured lung tissue. These indicated that ASCs could relieve RILI by inhibiting TGF-β1/Smad 3 signaling pathway.

In the study of environmental DNA (eDNA), the rate of water filtration and the amount of DNA obtained are of general interest to researchers. We compared the PCTE filters with different pore sizes in enriching total DNA and fish eDNA from water samples. We also designed and tested a new filter device with a PET pad (5 µm) superimposed on a PCTE membrane (3 µm) and compared it to a pure PCTE filter. A comprehensive evaluation of filtration time, eDNA concentration, fish DNA quantification, and fish species detected showed that the shortest average filtration time was obtained with the 8 μm pore size (2 min 9 s) and the longest average filtration time was obtained with the 0.2 μm pore size (32 min 6 s). The highest average DNA concentration was 3.785 ng/μL for the 0.2 μm filter and the lowest was 0.577 ng/μL for the 8 μm filter; meanwhile, the concentrations of fish DNA measured by quantitative PCR were 5.02E+02(8 μm), 4.79E+02(3 μm), 1.63E+03(1.2 μm), 5.95E+03(0.2 μm) copies of fish DNA per µl and there was no significant difference in the results between them (p > 0.05). The sequencing results showed that 17 fish species were detected in the 0.2 μm filter, 10 species in the 1.2 μm filter, 12 species in the 3 μm filter and 11 species in the 8 μm filter. Comparing to 3 μm and 0.2 um, the average filtration time in stacked-filter was reduced by 4 and 24 min, respectively, while the average concentration was 2.46 and 1.55 times higher than the former. The qPCR results showed that the number of eDNA copies of the samples enriched with the 3 µm and stacked-filter was 4.79E+02 and 1.53E+04, respectively. 3 μm and stacked-filter showed significant differences (p < 0.05), while 0.2 µm and stacked-filter did not show significant differences (p > 0.05). Sixteen fish species were detected by the stacked-filter. The number of eDNA obtained and the number of fish species detected were higher than those of the pure PCTE filter, while clogging during filtration was effectively avoided. We recommend using the stacked-filter to enrich eDNA from water samples.

The escalating environmental changes are imposing multiple pressures on biodiversity conservation, thereby, more attention has been paid to fish diversity and community assembly patterns. Fish diversity in Liaohe River has deteriorated significantly due to overfishing, environmental pollution and other reasons, in addition, no fish survey related research has been published in Liaohe National Park in recent years. In order to study the diversity of fish species in the area and to investigate the presence of any invasive species. This study used eDNA metabarcoding to explore the distribution and diversity of fish communities in the Liaohe National Park. The study showed that a total of 54 species of fish from six orders, 14 families, and 39 genera were detected, meantime, the invasive species Lepomis cyanellus was found at two sampling sites. The α-diversity results showed that estuarine sites had the highest species diversity. The spatial structure of fish communities in the upstream and downstream reaches were similar as indicated by non-metric multidimensional scaling. In our study, the fish community is influenced by both deterministic and stochastic processes, with the stochastic processes being the main factor. The potential existence of L. cyanellus in Liaohe National Park might be resulted from aquaculture, ornamental pet trade, other economic fish farming, artificial release. The relatively low number of fish species in this study may be attributed to the limited number of sampling events and sampling sites. In addition to these factors, over exploitation of resources, water pollution, and the invasion of alien species have directly impacted the biodiversity of aquatic life. The results of this study lay a foundation for the future biodiversity investigation in National Parks of China, meantime, the use of eDNA monitoring is crucial to prevent, to control and limit the spreading of invasive species in advance.

ABSTRACT Antibiotic resistance screening is crucial in the construction of recombinant plasmids. The dfrB10 gene, a short-size trimethoprim (TMP)-resistance type B dihydrofolate reductase gene, is a promising antibiotic drug screening marker for plasmid construction in molecular genetic research. Currently, available plasmid backbones (without the resistance gene) were amplified using PCR, and then we ligated these products with dfrB10 gene fragments via homologous recombination to construct new plasmid vectors with TMP resistance. The cloning, expression, and gene editing functions of the new plasmids based on their different purposes were verified. By successfully replacing the original resistance genes of pUC19, pET28a, pcDNA3.1, and pX330 plasmids with dfrB10, we constructed a series of plasmids with TMP resistance. The change of the resistance selection marker to TMP did not affect the function of the plasmids compared to the original ones. Furthermore, a short (988 bp) TMP-resistant miniature tool plasmid, pTMi, was constructed based on the pUC19 plasmid. With the use of the dfrB10 gene as a resistance marker under TMP drug screening, various size-reduced tool plasmids can be routinely constructed. These plasmids have similar functions to the original ones and can be used for research applications in molecular genetics. IMPORTANCE Plasmid size is one of the factors affecting transfection efficacy in most of the molecular genetic research studies. One effective approach for reducing plasmid size is to replace relatively large, conventional antibiotic resistance genes with the short-size dfrB10 gene. The successful construct of a series of dfrB10-based tool plasmids and their functional validation, via comparison with original plasmids, suggest that dfrB10 is a potent drug resistance selection marker. The antibiotic trimethoprim offers convenient usage comparable to that of ampicillin or kanamycin. Additionally, fluorescence analysis has demonstrated the compatibility of TMP with protein expression in various host cells. Based on these findings, TMP-dfrB10 could be an alternative choice for future use in molecular genetic research studies that require miniature plasmids to achieve optimal results.

Objective To discuss the significance of genetic diagnosis of children with syndromic hearing loss by using whole-exome sequencing. Methods The clinical data of 34 children with sensorineural hearing loss were collected and the whole exons of genome of the children and their parents were sequenced and analyzed. Results Genetic causative gene and mutations have been identified in 19 children, including 4 genes (HARS2, USH2A, GATA3, MITF) related to rare syndromic hearing loss. Fifteen children were diagnosed with non-syndromic hearing loss related gene, including 8 cases with GJB2 mutation, 5 cases with SLC26A4 mutation and 2 cases with MYO15A mutation. Mutations of c.435_437del(p.K147del) and c.1403G > C (p.G468A) in gene HARS2, c.11389+1del in gene USH2A, c.1327delA(p.M443Wfs*33) in gene GATA3, c.627C > A(p.C209X) in gene MITF and c.8033_8057delinsG(p.N2678_D2686delinsS) in gene MYO15A were first reported. Conclusions Whole-exome sequencing helps the accurate diagnosis of causes of hearing loss, especially for the rare syndromic hearing loss with atypical clinical manifestations. Information from genetic testing may highlight further recommended exams of structure and functions of related organs.

Rare diseases refer to a group of diseases having very low incident rates in the population without unified definition up till now. Approximately 50% to 75% of rare diseases occur at birth or in childhood, incurring huge psychological and economic burden to families and society. With the rapid development of diagnostic technology and the continuous progress in treatment and the introduction of relevant policies, China has made great progress in the prevention and treatment of rare diseases. This article summarizes the latest progress in the diagnosis, clinical management, and research of pediatric rare diseases; and explores the prospects in the future.