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关键词： Cyclophosphamide   Toxicity   Sensitivity   Body weight   Physiological and biochemical parameters  

摘要： The widespread use of cyclophosphamide (CP) in medical treatment had caused ubiquitous contamination in the environment. To data, many studies have been carried out on the toxic effect of CP. However, among these toxic effects of CP, which are the most sensitive remains unclear. Present study aimed to investigate the toxicity of CP on mice and evaluate the sensitivity of physiological-biochemical parameters upon exposure of mice to CP. Results showed that as compared with the control group, CP caused significant reduction in body weight (p < 0.01), spleen coefficient (p < 0.01), leukocyte density (p < 0.01) and alanine transaminase (ALT) in kidney (p < 0.01);However superoxide dismutase (SOD), malondialdehyde (MDA), ALT in liver and creatinine (Cr) in kidney significantly (p 0.05) increased. Among the suppressed physiological and biochemical parameters, the sensitivity to CP toxicity was generally ranked as body weight leukocyte density > ALT in kidney > spleen coefficient;while among the stimulated parameters, the sensitivity was ranked as MDA (liver) > Cr (kidney) > ALT (liver). Overall, the most sensitive parameters to CP toxicity may be associated with growth, immune system and the normal function of liver and kidney.

关键词： Yangze River Estuary   High-throughput sequencing   Community structure   Bacterial diversity  

摘要： Due to the geographical circumstances, the Yangtze River Estuary (YRE) and the adjacent East China Sea are extensively influenced by both anthropogenic activities and environmental factors. To reveal the responses of microbes in surface sediment to environmental factors and their contributions to the biogeochemical cycle in this area, surface sediment and overlying water samples were collected at 21 stations from the estuary to the coastal region. Water and sediment parameters were determined, and 16S rRNA genes of microbes in sediment samples were sequenced using high throughput sequencing technology. The results indicated that ocean currents, sediment density (SD), nutrients, sulfate (SO4-2), and salinity were the key factors shaping the microbial communities. Coastal microbes were affected mainly by SD, whereas anthropogenic discharge might have been responsible for a decrease in indigenous microbial diversity in the ocean. Due to the anthropogenic discharge, the most representative bacteria in the nearshore were aerobic and chemoheterotrophic bacteria, including ammonia-oxidizing bacteria, nitrite-oxidizing bacteria, denitrifying bacteria, and polyphosphate accumulating organisms. In the offshore, anaerobic bacteria, thermophilic bacteria, halophilic bacteria, sulfate-reducing bacteria, and sulfide oxidizing bacteria were the dominant bacteria, and these were characterized by strong solidarity and cooperative properties within the malnourished environment. In summary, these results provide a new perspective for revealing the biogeochemical significance of the bacterial lineages in the YRE, as well as constructive guidance for the management of the marginal sea ecosystems in distinct regions. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Soluble microbial products   Escherichia coli   Carbon source   Growth lifecycle   Membrane fouling  

摘要： The complexity of production process and chemical compositions of soluble microbial products (SMPs) largely limits the understanding of membrane fouling in membrane bioreactors (MBRs). Herein, we used a model single-strain Escherichia coli to better understand the chemical natures of SMPs and their roles in membrane fouling. The effects of carbon source and growth phase on the chemical compositions of SMPs were identified at both the compound and molecular levels by using advanced techniques including excitation emission matrix and parallel factor analysis (EEM-PARAFAC), size exclusion chromatography coupled with organic carbon detection (LC-OCD), and untargeted ultra-performance liquid chromatography Q-Exactive mass spectrometry (UPLC-Q-Exactive-MS). Subsequently, the roles of SMPs in the propensity of membrane fouling during ultrafiltration (UF) were studied. The results showed that the chemical compositions and fouling potentials of SMPs were carbon sourceand growth phase-dependent. In the exponential phase, SMPs mainly consisted of utilization-associated products (UAPs) and remaining substrates. As the microorganism progressed into the stationary and senescent phases, UAPs and biomass-associated products (BAPs) were the main components, respectively. The SMP contents generated in glucose medium were higher than those generated in acetate medium, and higher abundances of humic fluorescent components were observed in glucose-fed SMPs. Van Krevelen diagrams of the UPLCMS results revealed that acetate-fed SMPs contained more carboxylic-rich alicyclic molecules, peptideslike, aromatic, and carbohydrates-like components than glucose-fed SMPs in the stationary and senescent phases. These components played a significant role in irreversible membrane fouling, as evidenced in UF experiments. Standard blocking and cake filtration were the main fouling mechanisms for the filtration of SMPs collected in the exponential and stationary/senescent phases, respectively. Our findi

关键词： Oratosquilla oratoria   Reproductive biology   Biochemical changes   Feeding intensity   Broodstock  

摘要： Overexploitation and preliminary artificial breeding have led to an increasing interest in studying the reproductive biology and biochemical changes during gonad development in Oratosquilla oratoria. In this study, we established an accurate one-to-one correspondence between physical (and ovarian) morphology and ovarian histology during different maturity stages and improved the understanding of trophic dynamics with the progress of maturation, which will aid the aquaculture and artificial breeding techniques for this commercially important species. Based on ovarian histology and morphology, the ovaries were differentiated into six developmental stages, with five changes in color: immature stage (black), previtellogenesis (black), primary vitellogenesis (faint yellow), secondary vitellogenesis (golden yellow), maturation (light orange) and spent stage (brownish yellow). The visible colors of the median triangular structure of the telson can be used as an external morphological indicator of ovarian development status, and indicates that the females are near-ripe broods stocks when median triangular structure is almost filled with yellow. The gonadosomatic index (GSI) showed a statistically significant inverse correlation with the hepatopancreatic index (HPI) and muscle-somatic index (MSI). GSI significantly increased until stage III and HPI significantly decreased at stage II and recovered slowly thereafter. Nevertheless the MSI increased during the first two stages and decreased thereafter. A continuous decline in feeding intensity of females with ovarian development was found. The protein level in the muscle and hepatopancreas increased with protein accumulation in the ovary. Ovarian lipid concentration continued to increase, while, as in the hepatopancreas and muscle, lipid content decreased significantly at stage II and then recovered rapidly, followed by a sharp decline. Glycogen concentrations in the ovary kept steady, while in the hepatopancreas and muscle, th

关键词： Plastic optical fibers   Biosensors   Chemical sensors   Optical fiber sensors   Label-free sensing  

摘要： A review on bio-chemical label-free sensing applications based on receptors combined with multimode plastic optical fibers (POFs) is carried out. In particular, this work focuses on different kinds of POF intrinsic sensors used in transmission mode, exploiting various types of receptors and useful in several application fields. The sensor structures and the sensing mechanisms of different simple, highly sensitive, and low-cost POF probes are reported and compared. Moreover, different kinds of chemical and biological receptors combined with POF probes, highlighting the advantages and disadvantages of each receptor, are presented in detail. More specifically, the chosen POF sensing platforms, including low-cost and simple interrogation setups, are described showing their ability to monitor specific receptors exploiting intensity variation techniques and plasmonic phenomena, as well. Finally, a prospect of future developments of biochemical sensors with multimode POFs is discussed.

关键词： Spatial dynamics   Biochemical fractions   Enzymatic activity   Bacterial community   Co-bioevaporation  

摘要： Co-bioevaporation is a cleaner and sustainable production for treating concentrated landfill leachate (CLL). Temperature gradient in a co-bioevaporation pile resulted in a relatively wet matrix near the top, but drier conditions near the bottom. That made the biochemical fractions degradation (except of lipids) greatest near the top and lowest near the bottom. The total degraded biochemical fractions reached 191.96, 170.8 and 156.12 mg g(-1) TS (total solids), respectively in the top, middle and bottom sections of the pile. The highest enzymatic activity (including hydrolase and dehydrogenase) was observed in the top region, while the lowest was in the bottom region. The top region came to be dominated by thermophiles, particularly anaerobic Tepidimicrobium which accounted for 10.55% and 8.81%, respectively in the warming and peak temperature periods. Their activity as well as synergy with aerobes contributed to the higher enzymatic activity and faster degradation near the top of a co-bioevaporation pile. The dominant genera near the bottom were aerobic mesophiles or moderate thermophiles. These spatial variations were related to the spatial gradients in temperature, organics and moisture which form, as well as to oxygen availability. (c) 2020 Elsevier Ltd. All rights reserved.

关键词： Androgen insensitive syndrome (AIS)   Androgen receptor (AR) mutation   Disorder   differences of sex development (DSD)   Functional assay  

摘要： BackgroundAndrogen insensitive syndrome (AIS) is a rare genetic disease resulting from androgen receptor (AR) mutations and one of the causes of 46, XY disorder of sexual development (DSD). This study aimed to describe the clinical features and molecular defects of 36 Chinese patients with AR variants and investigate the functional alterations of novel variants in *** and methodsSubjects with AR variants were identified from 150 Chinese 46, XY DSD patients using targeted next-generation sequencing. In-silico and functional assays were performed to evaluate the transcriptional activity and nuclear localization of novel AR *** novel and fifteen reported AR variants were identified. 30.6% (11/36) of patients harbored additional variants other than AR. Mutations in the Arg841 residue were found in 7 unrelated patients. Postpubertal serum gonadotropin levels were significantly elevated in patients with complete AIS (CAIS) compared with those in patients with partial AIS (PAIS) (P<0.05). All the novel variants initially predicted to be uncertain significance by in-silico analyses were reclassified as likely pathogenic for defective AR transcriptional activity in vitro, except p.L295P, which was found in an atypical patient with oligogenic mutations and reclassified as likely benign. c.368_369 ins T was observed to interfere with nuclear *** with PAIS patients, postpubertal CAIS patients had higher gonadotropin levels. Arg841 was disclosed as the location of recurrent mutations in Chinese AIS patients. Functional assays are important for reclassifying the novel AR variants and re-examining the diagnosis of AIS in specific patients with oligogenic mutations, instead of in-silico analysis.

关键词： Cu mixed-ligand complexes   Density functional theory (DFT)   Antimicrobial activity   Phenoxazinone synthase-mimicking   Structure activity relationship  

摘要： Three new Cu(II) mixed-ligand complexes of the type [Cu(primary ligand)(secondary co-ligand)], were synthesized, characterized and preliminary tested for their biochemical activities. The primary ligand (HL) was derived from condensation of p-toluidine with 2-hydroxy-naphthalhyde. Three different N-heterocyclic compounds, 8-hydroxy-quinoline (HQ), 2-(1H-benzimidazol-2-yl)phenol (HB), and 2-(4,5-diphenyl-1H-imidazol-2-yl)phenol (HI), were used as secondary co-ligands. Inhibitory capacity of the synthesized compounds were screened against the growth of pathogenic bacteria [E. coli (G(-)) and B. cereus (G(+))] and fungi (A. fumigatus), in terms of inhibition zone (IZ, mm), and minimum inhibitory concentration (MIC, mu g/mL) using the disc diffusion method. Furthermore, the complexes were tested for their phenoxazinone synthase-like activity in terms of K-cat. Density functional theory (DFT) calculations based on B3LYP with LanL2DZ level of theory were performed to prove the proposed geometry of the complexes as well as evaluate the electronic parameters responsible for their reactivity. Structure activity relationship formula was derived by correlating the experimental data (MIC or K-cat) with the calculated electronic parameters. (C) 2020 Elsevier B.V. All rights reserved.

关键词： 虚拟仿真   实验教学   食品工程原理   教学改革  

摘要： 食品工程原理实验是食品专业学生的一门重要实验课程。目前,国内高校在实验课程开展过程中存在教学资源不足、学生积极性不高和考核方式不完善等问题。将虚拟仿真教学应用于食品工程原理实验课程中将有效地改善传统实验教学中存在的一系列问题,这也是国内各高校在该实验课程中探索的教育方式改革的方向之一。这种教学模式在培养自主学习能力强、具有创新精神的食品专业类人才做出重大贡献。