In this study, Gly→Ala was introduced into three chains of the heterotrimeric model (abc); seven mutants were subsequently constructed, and the local structure and global motion changes were analyzed. DSC results showed that the Tm value of the single point mutation was reduced by about 15°C, while the double and triple point mutations did not form triple helical structures. MD simulation trajectories were analyzed by ladder models; the results showed that the value of the step parameter changes near the mutation point, indicating an unfolding of the triple helix structure. An elastic function was introduced to quantify the degree of collagen structure change. It was found that the hydrogen bond energy was highly correlated with the structural deformation fraction ( $ R^2=0.76 $ ), indicating that the mutation not only destroyed the hydrogen bond force, but also resulted in changes in the bending and motion states of the molecule. This study, combined with calculations and experiments, helped quantify the effects of glycine mutation on the overall structure and movement pattern of collagen. Hence, the study provides a theoretical basis for clarifying the pathogenic mechanism of glycine mutation.
This research study focuses on Tettigoniidea and Gryllidea insects distributed across Shanghai Pujiang Country Park, with data collected twice a month from April to December of Year 2020 and 2021. The results show that 8 species of Tettigonioidea, 16 species of Grylloidea, and 1 species of Gryllotalpidae live in Shanghai Pujiang Country Park. The adult phase and voltinism in their life cycles, moreover, were found to be stable. Most Tettigoniidea and Gryllidea tend to overwinter in soil as diapause eggs, and a proportion of them overwinter as nymphs. The research suggests, furthermore, that using the calling songs of Tettigoniidea and Gryllidea can be a simple and effective way to carry out studies about phenology and ecology of singing insect.
Cricket fighting is a traditional Chinese game that has lasted for more than 1000 years. Before competitions, Xishuai grass (stimulant grass) is commonly used to hit a cricket’s head and antennae to prepare the insects for battle. In “Flora of China” and flora of Chinese provinces, Xishuai grass is referenced as the Chinese common name of Eleusine indica (L.) Gaertn. In “Flora of Beijing” and “Flora of Hebei”, Xishuai grass is referenced as the Chinese common name of the genus Eleusine. In this paper, however, we demonstrate that Xishuai grass should actually be Digitaria spp. Given the mistakes in the above flora references, this paper aims to clarify the correct classification for future reference.
In this study, the MS2 phages were used as an indicator microorganism to test the function of seven disinfectants with different components: hydrogen peroxide, ethanol, fermented lactic acid disinfectant, iodine disinfectant, quaternary ammonium disinfectant, chlorine-containing disinfectant, and peracetic acid disinfectant. Our results showed that the virus disinfection rate varied notably between the selected disinfectants. The iodine disinfectant exhibited the strongest disinfection effect, followed by the quaternary ammonium salt disinfectant and the peracetic acid disinfectant, while the disinfection effects of hydrogen peroxide, ethanol, and fermentation lactic acid disinfectant were inadequate. The test results provide a reference for the efficient utilization of various disinfectants to eliminate harmful microorganisms in the environment.
In this work, micro-scale porous carboxyl polystyrene microspheres (PS) were prepared using seed polymerization. Quantum dots (QDs) were used as fluorescent molecules to synthesize QDs with different emission wavelengths and successfully loaded into porous microspheres to form fluorescent coding microspheres (QDs@PS). Subsequently, serum samples of patients with acute leukemia (AL) were detected, and the antigen in the serum was quantitatively analyzed using flow cytometry. Scanning electron microscope (SEM) and flow cytometry images showed that the microspheres were regular and uniform in size. Fluorescence microscopy showed that the QDs permeated uniformly into the whole microsphere. In addition, QDs@PS showed good fluorescence stability, no QD leakage was observed, and the QDs@PS maintained its fluorescence for a period of at least two weeks. The use of fluorescence spectroscopic analysis for the detection of human immunoglobulin G (IgG) showed that the carboxyl groups on the surface of fluorescent microspheres are beneficial for the efficient covalent binding of biological macromolecules, which can be used for sandwich immunosandwich reaction coupling with leukemic high expression antigen interleukin 6 (IL-6). Combined with serum samples from leukemia patients, the fluorescence of QDs was detected by flow cytometry, and the mean fluorescence intensity (MFI) was calculated to determine the content of IL-6 in the serum. These results indicate that the designed optically-encoded microcarrier can be successfully applied to high-throughput and multichannel biomolecular analysis and has great potential in blood disease detection and diagnosis.
Plagiochila is one of the genera with the largest number of species among liverworts. A study was conducted to understand the diversity and distribution of the Plagiochila genus in Anhui Province. Based on the results of the study, there were 23 species of Plagiochila found in the region, of which seven species and one subspecies were first observed in Anhui Province. Floristic analysis showed that tropical Asian elements were the most abundant, accounting for 47.83%, and East Asian elements were the second most abundant, accounting for 34.78%. In the future, the accuracy of bryophyte identification can be further improved; meanwhile, the scope and depth of future investigations should be reinforced.
In this research, we carried out a survey based on one fixed transect for Tettigonioidea and Grylloidea insects distributed in Tianmu Mountain from April to October of 2019. The results showed that there were 28 species of Tettigonioidea and 19 species of Grylloidea in Tianmu Mountain. Among them, six species of Tettigonioidea and eight species of Grylloidea were recorded in Tianmu Mountain for the first time. The insects became adults in August, September, and October. The insects distributed at lower altitudes tended to become adults earlier than those at higher altitudes. The number of species declined initially with increasing altitude, and subsequently increased. The Tettigonioidea species are distributed at various altitudes while Grylloidea species are primarily distributed at low altitudes. Because Truljalia tylacantha, Ruidocollaris truncatolobata, Goniogryllus punctatus and some other species are only distributed in a narrow scope at high altitudes, they can be used as indicator species for climate change in Tianmu Mountain.
To better understand the diversity of bryophytes in East China, bryophytes were systematically investigated and collected in the Huangshan - Tianmu Mountain range and Xianxia - Wuyi Mountain range in the region. In the course of field investigation, eighteen new records of liverwort species were found in Zhejiang Province, belonging to 10 families and 13 genera, respectively. Notably, Hattoria is a new genus record for Zhejiang Province. In this paper, the habitats, geographical distributions, and main identifying features of these new records are provided. Moreover, illustrations of rare and endemic liverwort species in China are presented. These new findings further enrich the bryophyte flora of Zhejiang Province and provide new basic information about the flora of the province.
Two epiphyllous species, namely Cheilolejeunea chenii and C. obtusilobula, were newly recorded in Zhejiang Province. The specimens were collected from Gaoshanwan Village, Yushang Township, Qingyuan County, Zhejiang Province. It is worth noting that C. chenii has a very narrow distribution range in China and is a particularly rare species that should be protected as soon as possible. In this paper, the morphological characteristics, distribution, and habitats of the two species are briefly described and discussed. Given that the two species are not currently within the protection scope of the nature reserve, we also propose new ideas for in-situ conservation of epiphyllous liverworts.
In this study, the Shengli Coal Mine—a representative coal mine in the semi-arid grassland of Inner Mongolia—and the adjacent Beizi Temple, Botanical Garden, and Nanshan Reservoir were selected as the study areas. By studying the correlation between the characteristics of the bryophyte community and the physical and chemical properties of the soil, the influence of soil on the distribution of bryophytes was analyzed during the reclamation process. The results showed that there were 4 families, 6 genera, and 7 species of bryophytes in the Shengli mining area. The total coverage of bryophytes in each habitat could be ranked according to the following order: Beizi Temple > Botanical Garden > south dump of the mining area > Nanshan Reservoir > plantation in the mining area > north dump of the mining area. An analysis of the diversity index, moreover, showed that the Shannon-Wiener index at the south dump was the highest, indicating that the species complexity of the moss community at the south dump was relatively high. An analysis of the correlation between the coverage of the bryophyte community and the physical and chemical properties of the soil showed that the soil pH value, silt content, sand content, and gravel content all had significant effects on the distribution of bryophytes. Multivariate analysis of the bryophyte community structure and soil physical and chemical properties showed that the differences in bryophyte community structure between different study areas was related to the cumulative influence of environmental factors.
In this paper, we studied a new preparation technique for lyophilized lentiviral vectors. We determined the optimal formulation for a freeze-drying protective agent by screening and optimizing potential candidates. The candidates were evaluated on the basis of physical and chemical properties of the freeze-drying process, including appearance, excipient, color, and solubility. The optimal formulation was determined to be trehalose 0.30 g/mL, L-histidine 0.31 mg/mL, L- alanine 0.178 mg/mL, CaCl2 0.020 mg/mL, and MgSO4 0.015 mg/mL. With this technique, the prepared lyophilized lentiviral vector had good appearance, low residual water content, intact structure, and good re-dispersibility. The biological titer of the lentiviral vector reached 9.37 × 107 IU/mL, and the recovery rate of the titer was 50.15%. We also conducted research on potential influencing factors, including a high temperature accelerated experiment and repeated freeze-thaw stability experiments. These experiments showed that the lyophilizing technology can be used for the preparation of lentiviral vector solids and can be effectively used to improve the storage of lentiviral vectors under different temperature conditions, exposure to repeated freeze-thaw cycles, and tolerance to adverse environments (e.g., high temperatures).
中国综合性科技类核心期刊(北大核心)
