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1.
J Environ Manage ; 342: 118152, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37201393

RESUMO

Eutrophication of lacustrine environments with frequent cyanobacterial blooms has become a serious problem. Overpopulation and runoff into groundwater and lakes from fertilizers with too much nitrogen and phosphorous have caused most of the problems. Here, we first devised a land use and cover classification system based on the local characteristics of the first-level protected area of Lake Chaohu (FPALC). Lake Chaohu is the fifth largest freshwater lake in China. The land use and cover change (LUCC) products were produced using sub-meter resolution satellite data from 2019 to 2021 in the FPALC. This study presents an evaluation of the effectiveness of the established protected areas. The results show the most impactful type was the reduction in cropland with an area that declined from 7446.4 hm2 to 6433.3 hm2 from 2019 to 2021. Most of the reduced cropland was converted into wetlands, with 460.2 hm2 and 152.0 hm2 of cropland restored to wetlands from 2019 to 2020 and 2020-2021, respectively. The area of cyanobacterial blooms in Lake Chaohu showed a downward trend, and the lacustrine environment was greatly improved after the establishment of the FPALC. These quantified data can inform decision-making related to Lake Chaohu conservation and provide a reference for managing the aquatic environment in other watersheds.


Assuntos
Cianobactérias , Lagos , Eutrofização , Áreas Alagadas , Fósforo
2.
Molecules ; 27(13)2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35807472

RESUMO

The current detection method of carbendazim suffers from the disadvantages of complicated preprocessing and long cycle time. In order to solve the problem of rapid quantitative screening of finite contaminants, this article proposed a qualitative method based on characteristic peaks and a semi-quantitative method based on threshold to detect carbendazim in apple, and finally the method is evaluated by a validation system based on binary output. The results showed that the detection limit for carbendazim was 0.5 mg/kg, and the detection probability was 100% when the concentration was no less than 1 mg/kg. The semi-quantitative analysis method had a false positive rate of 0% and 5% at 0.5 mg/kg and 2.5 mg/kg, respectively. The results of method evaluation showed that when the added concentration was greater than 2.5 mg/kg, the qualitative detection method was consistent with the reference method. When the concentration was no less than 5 mg/kg, the semi-quantitative method is consistent between different labs. The semi-quantitative method proposed in this study can achieve the screening of finite contaminants in blind samples and simplify the test validation process through the detection probability model, which can meet the needs of rapid on-site detection and has a good application prospect.


Assuntos
Frutas , Análise Espectral Raman , Benzimidazóis/análise , Carbamatos/análise , Frutas/química , Análise Espectral Raman/métodos
3.
Environ Sci Technol ; 54(21): 13709-13718, 2020 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-33079540

RESUMO

Lakes play an important role in the global carbon cycle; however, there are still large uncertainties in the estimation of global lake carbon emission due to the limitations in conducting field surveys at large geographic scales. Using long-term Moderate-Resolution Imaging Spectroradiometer (MODIS) imagery and field observation data in eutrophic Lake Taihu, we developed a novel approach to estimate the concentration of dissolved carbon dioxide (cCO2) in lakes. Based on the MODIS-derived chlorophyll-a concentration, lake surface temperature, diffuse attenuation coefficient of photosynthetically active radiation, and photosynthetically active radiation, a spatially explicit cCO2 model was developed using multivariate quadratic polynomial regression (coefficient of determination (R2) = 0.84, root-mean-square error (RMSE) = 11.81 µmol L-1, unbiased percent difference (UPD) = 22.46%). Monte Carlo simulations indicated that the model is stable with relatively small deviations in cCO2 estimates caused by input variables (UPD = 26.14%). MODIS data from 2003 to 2018 showed a significant declining trend (0.42 µmol L-1 yr-1, p < 0.05) in the annual mean cCO2. This was associated with a complex balance between the increasing algae biomass and decreasing external inputs of inorganic carbon, nutrients, and organic matter. The high spatiotemporal variabilities in cCO2 were attributed to river inputs and seasonal changes in temperature and algae biomass. The study shows that satellite remote sensing can play an important role in the field of inland water carbon cycling, providing timely much-needed insights into the drivers of the spatial and temporal changes in dissolved CO2 concentrations in inland waters.


Assuntos
Dióxido de Carbono , Lagos , Ciclo do Carbono , Dióxido de Carbono/análise , China , Clorofila A , Monitoramento Ambiental
4.
Fish Shellfish Immunol ; 87: 346-359, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30677515

RESUMO

To better understand the immune system of shrimp, this study combined PacBio isoform sequencing (Iso-Seq) and Illumina paired-end short reads sequencing methods to discover full-length immune-related molecules of the Pacific white shrimp, Litopenaeus vannamei. A total of 72,648 nonredundant full-length transcripts (unigenes) were generated with an average length of 2545 bp from five main tissues, including the hepatopancreas, cardiac stomach, heart, muscle, and pyloric stomach. These unigenes exhibited a high annotation rate (62,164, 85.57%) when compared against NR, NT, Swiss-Prot, Pfam, GO, KEGG and COG databases. A total of 7544 putative long noncoding RNAs (lncRNAs) were detected and 1164 nonredundant full-length transcripts (449 UniTransModels) participated in the alternative splicing (AS) events. Importantly, a total of 5279 nonredundant full-length unigenes were successfully identified, which were involved in the innate immune system, including 9 immune-related processes, 19 immune-related pathways and 10 other immune-related systems. We also found wide transcript variants, which increased the number and function complexity of immune molecules; for example, toll-like receptors (TLRs) and interferon regulatory factors (IRFs). The 480 differentially expressed genes (DEGs) were significantly higher or tissue-specific expression patterns in the hepatopancreas compared with that in other four tested tissues (FDR <0.05). Furthermore, the expression levels of six selected immune-related DEGs and putative IRFs were validated using real-time PCR technology, substantiating the reliability of the PacBio Iso-seq results. In conclusion, our results provide new genetic resources of long-read full-length transcripts data and information for identifying immune-related genes, which are an invaluable transcriptomic resource as genomic reference, especially for further exploration of the innate immune and defense mechanisms of shrimp.


Assuntos
Imunidade Inata/genética , Penaeidae/genética , Penaeidae/imunologia , Transcriptoma/imunologia , Animais , Perfilação da Expressão Gênica , Reação em Cadeia da Polimerase em Tempo Real
5.
Curr Microbiol ; 75(10): 1352-1361, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29922970

RESUMO

Bats can be divided into frugivory, nectarivory, insectivory, and sanguivory based on their diets, and are therefore ideal wild animal models to study the relationship between diets and intestinal microflora. Early studies of bat gut bacteria showed that the diversity and structure of intestinal bacterial communities in bats are closely related to dietary changes. Worthy of note, intestinal microbes are composed of bacteria, fungi, protozoa, and archaea. Although the number of gut fungi is much lower than that of gut bacteria, they also play an important role in maintaining the host homeostasis. However, there are still few reports on the relationship between the gut mycobiota and the dietary habits of the host. In addition, bats have also been shown to naturally transmit pathogenic viruses and bacteria through their feces and saliva, but fungal infections from bat are less studied. Here, we used high-throughput sequencing of bacterial 16S and eukaryotic 18S rRNA genes in the V4 and V9 regions to characterize fecal bacterial and fungal microbiota in phytophagous and insectivorous bats in South China. The results show that the gut microbiota in bats were dominated by bacterial phyla Proteobacteria, Firmicutes, Tenericutes and Bacteroidetes, and fungal phyla Ascomycota and Basidiomycota. There was a significant difference in the diversity of bacterial and fungal microbiota between the groups, in addition to specific bacteria and fungi populations on each of them. Of note, the number of fungi in the feces of herbivorous bats is relatively higher. Most of these fungi are foodborne and are also pathogens of humans and other animals. Thus, bats are natural carriers of fungal pathogens. The current study expands the understanding of the bat gut bacterial and fungal mycobiota and provides further insight into the transmission of fungal pathogens.


Assuntos
Ração Animal , Quirópteros , Fezes/microbiologia , Microbiota , Animais , Bactérias/classificação , Bactérias/genética , Biodiversidade , China , Feminino , Fungos/classificação , Fungos/genética , Humanos , Masculino , Metagenoma , Metagenômica/métodos , Filogenia , RNA Ribossômico 16S/genética , RNA Ribossômico 18S/genética
6.
Int J Mol Sci ; 17(4): 543, 2016 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-27077853

RESUMO

Turtles grow slowly and have a long lifespan. Ultrastructural studies of the pituitary gland in Reeves' turtle (Chinemys reevesii) have revealed that the species possesses a higher nucleoplasmic ratio and fewer secretory granules in growth hormone (GH) cells than other animal species in summer and winter. C. reevesii GH gene was cloned and species-specific similarities and differences were investigated. The full GH gene sequence in C. reevesii contains 8517 base pairs (bp), comprising five exons and four introns. Intron 1 was found to be much longer in C. reevesii than in other species. The coding sequence (CDS) of the turtle's GH gene, with and without the inclusion of intron 1, was transfected into four cell lines, including DF-1 chicken embryo fibroblasts, Chinese hamster ovary (CHO) cells, human embryonic kidney 293FT cells, and GH4C1 rat pituitary cells; the turtle growth hormone (tGH) gene mRNA and protein expression levels decreased significantly in the intron-containing CDS in these cell lines, compared with that of the corresponding intronless CDS. Thus, the long intron 1 of GH gene in Reeves' turtle might correlate with downregulated gene expression.


Assuntos
Clonagem Molecular/métodos , Hormônio do Crescimento/genética , Íntrons , Proteínas de Répteis/genética , Tartarugas/metabolismo , Animais , Células CHO , Linhagem Celular , Embrião de Galinha , Cricetinae , Cricetulus , Regulação da Expressão Gênica , Células HEK293 , Humanos , Filogenia , Ratos , Especificidade da Espécie , Tartarugas/genética
7.
Int J Mol Sci ; 17(11)2016 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-27834851

RESUMO

The effects of introns, especially the first intron, on the regulation of gene expression remains unclear. Therefore, the objective of the present study was to investigate the transcriptional regulatory function of intron 1 on the chicken growth hormone (cGH) gene in the rat pituitary tumor cell line (GH4-C1). Transient transfection using first-intron-inserted cGH complete coding sequences (CDSs) and non-intron-inserted cGH CDS plasmids, quantitative RT-PCR (qRT-PCR) and western blot assays were used to detect the expression of cGH. The reporter gene assay was also used to investigate the effect of a series of fragments in the first intron of cGH on gene expression in GH4-C1. All of the results revealed that a 200-bp fragment located in the +485/+684 region of intron 1 was essential for repressing the expression of cGH. Further informatics analysis showed that there was a cluster of 13 transcriptional factor binding sites (TFBSs) in the +485/+684 region of the cGH intron 1. Disruption of a glucocorticoid response-like element (the 19-nucleotide sequence 5'-AGGCTTGACAGTGACCTCC-3') containing a T-box motif (TGACCT) located within this DNA fragment increased the expression of the reporter gene in GH4-C1. In addition, an electrophoretic mobility shift assay (EMSA) revealed a glucocorticoid receptor (GR) protein of rat binding to the glucocorticoid response-like element. Together, these results indicate that there is a negative glucocorticoid response-like element (nGRE) located in the +591/+609 region within the first intron of cGH, which is essential for the down-regulation of cGH expression.


Assuntos
Regulação da Expressão Gênica , Hormônio do Crescimento/genética , Íntrons , Receptores de Glucocorticoides/genética , Elementos de Resposta , Somatotrofos/metabolismo , Animais , Sequência de Bases , Sítios de Ligação , Linhagem Celular Tumoral , Galinhas , Éxons , Glucocorticoides/farmacologia , Hormônio do Crescimento/metabolismo , Humanos , Fases de Leitura Aberta , Hipófise/efeitos dos fármacos , Hipófise/metabolismo , Hipófise/patologia , Plasmídeos/química , Plasmídeos/metabolismo , Ligação Proteica , Ratos , Receptores de Glucocorticoides/metabolismo , Somatotrofos/efeitos dos fármacos , Somatotrofos/patologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcrição Gênica , Transfecção , Transgenes
8.
Sci Total Environ ; 939: 173601, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-38810759

RESUMO

Climate change and human activities have crucial effects on the variations in phytoplankton blooms in lakes worldwide. A record-breaking heatwave and drought event was reported in the middle and lower reaches of the Yangtze River during the summer of 2022, but only little is known about how cyanobacterial blooms in lakes respond to such climate extremes. Here, we utilized MODIS images to generate the area, occurrence, and initial blooming date (IBD) of cyanobacterial blooms in Lake Chaohu from 2000 to 2022. We found that the area and occurrence of cyanobacterial blooms were largely reduced. At the same time, the IBD was delayed in 2022 compared with the previous 20 years. The annual occurrence and mean area of cyanobacterial blooms in 2022 were 17 % and 23.1 km2, respectively, which were the lowest reported levels since the 21st century. The IBD in 2022 was four months late compared with the IBD in 2020. The high wind speed in spring delayed the spring blooms in 2022. The record-breaking heatwaves and drought from June to August reduced the blooms by influencing the growth of cyanobacteria and reducing the flow of nutrients from the watershed into the lake. This study highlights the compound impact of heatwave and drought climate events on reducing cyanobacterial blooms in a long-term period, enhancing additional understanding of the changes in phytoplankton blooms in lakes.


Assuntos
Mudança Climática , Cianobactérias , Monitoramento Ambiental , Eutrofização , Lagos , Lagos/microbiologia , Cianobactérias/crescimento & desenvolvimento , China , Fitoplâncton , Estações do Ano , Secas
9.
Sci Total Environ ; 927: 172194, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38575038

RESUMO

Aquaculture ponds (APs) are rapidly expanding globally and are considered crucial for guaranteeing the supply of food, population growth, and economic development. However, the rapid expansion of aquaculture not only brought benefits but also a series of eco-environmental issues, such as water eutrophication. To achieve sustainable development, it is essential to gain a profound understanding of the spatiotemporal evolution of APs, the drivers behind their dynamics, and their relationship with the aquatic environment. Jiangsu Province (JS) in China, a historically significant aquaculture region, encompasses two prominent river basins: the Huai River Basin (HRB) and the Yangtze River Basin (YRB). In light of the construction of an ecological civilization, JS serves as a demonstration and pioneering area for basin protection and development. Therefore, this study focuses on JS, aiming to elucidate the spatiotemporal dynamics of APs, the corresponding relationship with basin management policies, and the impact on water eutrophication. The results revealed that: (1) in 2022, APs in JS were unevenly distributed, with a total area of 3278.78 km2, of which 79 % was located in the HRB. (2) During 2016-2022, APs exhibited an initial growth trend before 2019, followed by a decrease. (3) Due to policy interventions, AP changes within different basins showed opposite trends, and the corresponding water eutrophic state aligned with AP dynamics. The findings of this study can serve as a typical case to provide scientific evidence for the formulation and implementation of policies to improve the water environment in eutrophic basins.

10.
Sci Total Environ ; 880: 163376, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37031931

RESUMO

Under the influence of climate warming and human activities, many large lakes have experienced an increase in eutrophication and algal blooms. Although these trends have been identified using low temporal resolution (~16 days) satellites such as those of the Landsat missions, the opportunity to compare high-frequency spatiotemporal variations of algal bloom characteristics between lakes has not been explored. In the present study, we explore daily satellite observations by developing a universal, practical, and robust algorithm to identify the spatiotemporal distribution of algal bloom dynamics in large lakes (>500 km2) across the globe. Data from 161 lakes, taken from 2000 to 2020 showed an average accuracy of 79.9 %. Algal blooms were detected in 44 % of all lakes, with a higher incidence in temperate lakes (67 % of all temperate lakes), followed by tropical lakes (59 %) compared to lakes in arid climates (23 %). We found positive trends in bloom area and frequency (p < 0.05), as well as an earlier bloom time (p < 0.05). Climate factors were found to be linked to changes in annual initial bloom time (44 %); while an increase in human activities was associated to bloom duration (49 %), area (max percent: 53 %, mean percent: 45 %), and frequency (46 %). The study shows the evolution of daily algal blooms and their phenology in global large lakes for the first time. Such information enhances our understanding of algal bloom dynamics and their drivers, with important considerations to improve the management of large lake ecosystems.


Assuntos
Ecossistema , Monitoramento Ambiental , Humanos , Lagos , Eutrofização , Clima , China
11.
Water Res ; 245: 120648, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37738941

RESUMO

Cyanobacterial blooms release a large number of algal toxins (e.g., Microcystins, MCs) and seriously threaten the safety of drinking water sources what the SDG 6.1 pursues (to provide universal access to safe drinking water by 2030, United Nations Sustainable Development Goal). Nevertheless, algal toxins in lake water have not been routinely monitored and evaluated well and frequently so far. In this study, a total of 100 large lakes (>25 km2) in densely populated eastern China were studied, and a remote sensing scheme of human health risks from MCs based on Sentinel-3 OLCI data was developed. The spatial and temporal dynamics of MCs risk in eastern China lakes since OLCI satellite observation data (2016-2021) were first mapped. The results showed that most of the large lakes in eastern China (80 out of 100) were detected with the occurrence of a high risk of more than 1 pixel (300×300 m) at least once. Fortunately, in terms of lake areas, the frequency of high human health risks in most waters (70.93% of total lake areas) was as less as 1%. This indicates that drinking water intakes can be set in most waters from the perspective of MCs, yet the management departments are required to reduce cyanobacterial blooms. This study highlights the potential of satellite in monitoring and assessing the risk of algal toxins and ensuring drinking water safety. It is also an important reference for SDG 6.1 reporting for lakes that lack routine monitoring.


Assuntos
Cianobactérias , Água Potável , Humanos , Microcistinas/análise , Desenvolvimento Sustentável , Lagos/microbiologia , Medição de Risco , China , Monitoramento Ambiental
12.
Poult Sci ; 102(10): 102931, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37499616

RESUMO

The gut microbiome plays an important role in quail feed efficiency, immunity, production, and even behavior. Gut microbial gene catalogs and reference genomes are important for understanding the quail gut microbiome. However, quail gut microbes are lacked sequenced genomes and functional information to date. In this study, we report the first catalog of the microbial genes and metagenome-assembled genomes (MAGs) in fecal and cecum luminal content samples from 3 quail breeds using deep metagenomic sequencing. We identified a total of 2,419,425 nonredundant genes in the quail genome catalog, and a total of 473 MAGs were reconstructed through binning analysis. At 95% average nucleotide identity, the 473 MAGs were clustered into 283 species-level genome bins (SGBs), of which 225 SGBs belonged to species without any available genomes in the current database. Based on the quail gene catalog and MAGs, we identified 142 discriminative bacterial species and 244 discriminative MAGs between Chinese yellow quails and Japanese quails. The discriminative MAGs suggested a strain-level difference in the gut microbial composition. Additionally, a total of 25 Kyoto Encyclopedia of Genes and Genomes functional terms and 88 carbohydrate-active enzymes were distinctly enriched between Chinese yellow quails and Japanese quails. Most of the different species and MAGs were significantly interrelated with the shifts in the functional capacities of the quail gut microbiome. Taken together, we constructed a quail gut microbial gene catalog and enlarged the reference of quail gut microbial genomes. The results of this study provide a powerful and invaluable resource for quail gut microbiome-related research.


Assuntos
Microbioma Gastrointestinal , Metagenoma , Animais , Codorniz/genética , Galinhas/genética , Genes Microbianos
13.
Front Nutr ; 10: 1279141, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37899822

RESUMO

Chinese indigenous chickens have a long history of natural and artificial selection and are popular for their excellent meat quality and unique flavor. This study investigated six meat quality-related traits in Ningdu yellow, Baier yellow, Kangle, and Shengze 901 chickens. Two-dimensional gas chromatography-time-of-flight mass spectrometry was used to detect unique flavors in 24 breast muscle samples from the same phenotyped chickens. Overall, 685, 618, 502, and 487 volatile organic compounds were identified in Ningdu yellow, Baier yellow, Kangle, and Shengze 901 chickens, respectively. The flavor components were separated into eight categories, including hydrocarbons and aldehydes. Multivariate analyses of the identified flavor components revealed some outstanding features of these breeds. For example, the hydrocarbons (22.09%) and aldehydes (14.76%) were higher in Ningdu yellow chickens and the highest content of N, N-dimethyl-methylamine was in Ningdu yellow, Baier yellow, and Shengze 901 chickens, indicating the maximum attribution to the overall flavor (ROAV = 439.57, 289.21, and 422.80). Furthermore, we found that 27 flavor compounds differed significantly among the four Chinese breeds, including 20 (e.g., 1-octen-3-ol), two (e.g., 2-methyl-naphthalene), four (e.g., 2,6-lutidine), and one (benzophenone) flavor components were showed significant enrichment in Ningdu yellow, Baier yellow, Kangle, and Shengze 901 chickens, respectively. The flavor components enriched in each breed were key biomarkers distinguishing breeds and most were significantly correlated with meat quality trait phenotypes. These results provide novel insights into indigenous Chinese chicken meat flavors.

14.
Poult Sci ; 102(7): 102762, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37209654

RESUMO

Increasing evidence indicates that the gut microbiome plays an important role in host aging and sexual maturity. However, the gut microbial taxa associated with sexual maturity in quails are unknown. This study used shotgun metagenomic sequencing to identify bacterial taxa associated with sexual maturity in d 20 and d 70 quails. We found that 17 bacterial species and 67 metagenome-assembled genomes (e.g., Bacteroides spp. and Enterococcus spp.) significantly differed between the d 20 and d 70 groups, including 5 bacterial species (e.g., Enterococcus faecalis) enriched in the d 20 group and 12 bacterial species (e.g., Christensenella massiliensis, Clostridium sp. CAG:217, and Bacteroides neonati) which had high abundances in the d 70 group. The bacterial species enriched in d 20 or d 70 were key biomarkers distinguishing sexual maturity and significantly correlated with the shifts in the functional capacities of the gut microbiome. Untargeted serum metabolome analysis revealed that 5 metabolites (e.g., nicotinamide riboside) were enriched in the d 20 group, and 6 metabolites (e.g., D-ribose, stevioside, and barbituric acid) were enriched in the d 70 group. Furthermore, metabolites with high abundances in the d 20 group were significantly enriched for the KEGG pathways of arginine biosynthesis, nicotinate and nicotinamide metabolism, and lysine degradation. However, glutathione metabolism and valine, leucine and isoleucine biosynthesis were enriched in high-abundance metabolites from the d 70 group. These results provide important insights into the effects of gut microbiome and host metabolism on quail sexual maturity.


Assuntos
Microbioma Gastrointestinal , Animais , Galinhas , Metaboloma , Metagenoma , Bactérias , Biomarcadores
15.
J Funct Biomater ; 14(1)2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36662087

RESUMO

In the last few decades Additive Manufacturing has advanced and is becoming important for biomedical applications. In this study we look at a variety of biomedical devices including, bone implants, tooth implants, osteochondral tissue repair patches, general tissue repair patches, nerve guidance conduits (NGCs) and coronary artery stents to which fused deposition modelling (FDM) can be applied. We have proposed CAD designs for these devices and employed a cost-effective 3D printer to fabricate proof-of-concept prototypes. We highlight issues with current CAD design and slicing and suggest optimisations of more complex designs targeted towards biomedical applications. We demonstrate the ability to print patient specific implants from real CT scans and reconstruct missing structures by means of mirroring and mesh mixing. A blend of Polyhydroxyalkanoates (PHAs), a family of biocompatible and bioresorbable natural polymers and Poly(L-lactic acid) (PLLA), a known bioresorbable medical polymer is used. Our characterisation of the PLA/PHA filament suggest that its tensile properties might be useful to applications such as stents, NGCs, and bone scaffolds. In addition to this, the proof-of-concept work for other applications shows that FDM is very useful for a large variety of other soft tissue applications, however other more elastomeric MCL-PHAs need to be used.

16.
ACS Omega ; 7(2): 2064-2073, 2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-35071894

RESUMO

To develop a rapid detection method for nonprotein nitrogen adulterants, this experiment sets up a set of point-scan Raman hyperspectral imaging systems to qualitatively distinguish and quantitatively and positionally analyze samples spiked with a single nonprotein nitrogen adulterant and samples spiked with a mixture of nine nonprotein nitrogen adulterants at different concentrations (5 × 10-3 to 2.000%, w/w). The results showed that for samples spiked with single nonprotein nitrogen adulterants, the number of pixels corresponding to the adulterant in the region of interest increased linearly with an increase in the analyte concentration, the average coefficient of determination (R 2) was above 0.99, the minimum detection concentration of nonprotein nitrogen adulterants reached 0.010%, and the relative standard deviation (RSD) of the predicted concentration was less than 6%. For the sample spiked with a mixture of nine nonprotein nitrogen adulterants, the standard curve could be used to accurately predict the additive concentration when the additive concentration was greater than 1.200%. The detection method established in this study has good accuracy, high sensitivity, and strong stability. It provides a method for technical implementation of real-time and rapid detection of adulterants in milk powder at the port site and has good application and promotion prospects.

17.
Innovation (Camb) ; 2(2): 100092, 2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34557746

RESUMO

The recent mass mortality event of more than 330 African elephants in Botswana has been attributed to biotoxins produced by cyanobacteria; however, scientific evidence for this is lacking. Here, by synthesizing multiple sources of data, we show that, during the past decades, the widespread hypertrophic waters in Southern Africa have entailed an extremely high risk and frequent exposure of cyanotoxins to the wildlife within this area, which functions as a hotspot of mammal species richness. The hot and dry climatic extremes have most likely acted as the primary trigger of the recent and perhaps also of prehistoric mass mortality events. As such climate extremes are projected to become more frequent in Southern Africa in the near future, there is a risk that similar tragedies may take place, rendering African megafauna species, especially those that are already endangered, in risk of extinction. Moreover, cyanotoxin poisoning amplified by climate change may have unexpected cascading effects on human societies. Seen within this perspective, the tragic mass death of the world's largest terrestrial mammal species serves as an alarming early warning signal of future environmental catastrophes in Southern Africa. We suggest that systematic, quantitative cyanotoxin risk assessments are made and precautionary actions to mitigate the risks are taken without hesitation to ensure the health and sustainability of the megafauna and human societies within the region.

18.
Front Vet Sci ; 8: 693755, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34660751

RESUMO

Background: Japanese quail (Coturnix japonica) are important and widely distributed poultry in China. Researchers continue to pursue genetic selection for heavier quail. The intestinal microbiota plays a substantial role in growth promotion; however, the mechanisms involved in growth promotion remain unclear. Results: We generated 107.3 Gb of cecal microbiome data from ten Japanese quail, providing a series of quail gut microbial gene catalogs (1.25 million genes). We identified a total of 606 main microbial species from 1,033,311 annotated genes distributed among the ten quail. Seventeen microbial species from the genera Anaerobiospirillum, Alistipes, Barnesiella, and Butyricimonas differed significantly in their abundances between the female and male gut microbiotas. Most of the functional gut microbial genes were involved in metabolism, primarily in carbohydrate transport and metabolism, as well as some active carbohydrate-degrading enzymes. We also identified 308 antibiotic-resistance genes (ARGs) from the phyla Bacteroidetes, Firmicutes and Euryarchaeota. Studies of the differential gene functions between sexes indicated that abundances of the gut microbes that produce carbohydrate-active enzymes varied between female and male quail. Bacteroidetes was the predominant ARG-containing phylum in female quail; Euryarchaeota was the predominant ARG-containing phylum in male quail. Conclusion: This article provides the first description of the gene catalog of the cecal bacteria in Japanese quail as well as insights into the bacterial taxa and predictive metagenomic functions between male and female quail to provide a better understanding of the microbial genes in the quail ceca.

19.
Anal Chim Acta ; 1096: 193-202, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31883587

RESUMO

Specific recognition of caffeic acid (CA) from Taraxacum mon-golicum Hand.-Mazz. was successfully performed using a new pH responsive magnetic molecularly imprinted polymers (pH-MMIPs) by simple surface molecular imprinting polymerization. The pH-MMIPs were prepared on the surface of the Fe3O4@SiO2@MPS particles using CA as a template, 2-(dimethylamino) ethyl methacrylate (DMA) as the pH responsive functional monomer, 4-vinylpyridine (4-VP) as an assisting functional monomer, ethylene glycol dimethyl acrylate (EGDMA) as cross-linker, 2,2'-azobisisobutyronitrile (AIBN) as initiator and methanol-H2O (1:1, v/v) as the porogen. The resultant polymers were characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FT-IR), thermal gravimetric analysis (TGA), vibrating sample magnetometry (VSM) and x-ray diffraction (XRD). The adsorption experiments revealed that the pH-MMIPs performed high adsorption ability (11.5 mg g-1) by changing solution pH. Successful selective adsorption of CA was achieved with distribution coefficient of 0.12 and 0.21 towards ferulic acid and chlorogenic acid. Furthermore, pH-MMIPs were employed as adsorbents for extraction and enrichment of CA from Taraxacum mon-golicum Hand.-Mazz. extract. The recoveries of CA in the Taraxacum mon-golicum Hand.-Mazz. ranged from 90.47% to 98.97%. The results proved that the polymers have the potential to provide a selective recognition of CA in complex samples by simple pH regulation.


Assuntos
Ácidos Cafeicos/isolamento & purificação , Impressão Molecular/métodos , Polímeros/química , Taraxacum/química , Adsorção , Óxido Ferroso-Férrico/química , Concentração de Íons de Hidrogênio , Imãs/química , Metacrilatos/química , Polimerização , Piridinas/química , Dióxido de Silício/química
20.
PeerJ ; 7: e6574, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30886772

RESUMO

The crocodile lizard (Shinisaurus crocodilurus Ahl, 1930) is an endangered reptile species, and in recent years many have died from diseases, especially the rescued and breeding individuals. However, pathogens underlying these diseases are unclear. In this study, we report our effort in rapidly identifying and isolating the pathogen that causes high mortality in crocodile lizards from Guangdong Luokeng Shinisaurus crocodilurus National Nature Reserve. The typical symptom is cutaneous granuloma in the infected crocodile lizards. Metagenomic next-generation sequencing (mNGS) is a comprehensive approach for sequence-based identification of pathogenic microbes. In this study, 16S rDNA based mNGS was used for rapid identification of pathogens, and microscopy and microbe isolation were used to confirm the results. Austwickia chelonae was identified to be the dominant pathogen in the granuloma using 16S rDNA based mNGS. Chinese skinks were used as an animal model to verify the pathogenicity of A. chelonae to fulfill Koch's postulates. As expected, subcutaneous inoculation of A. chelonae induced granulomas in the healthy Chinese skinks and the A. chelonae was re-isolated from the induced granulomas. Therefore, A. chelonae was the primary pathogen that caused this high mortality disease, cutaneous granuloma, in crocodile lizards from Guangdong Luokeng Shinisaurus crocodilurus National Nature Reserve. Antibiotics analysis demonstrated that A. chelonae was sensitive to cephalothin, minocycline and ampicillin, but not to kanamycin, gentamicin, streptomycin and clarithromycin, suggesting a possible treatment for the infected crocodile lizards. However, surgical resection of the nodules as early as possible was recommended. This study is the first report of pathogenic analysis in crocodile lizards and provides a reference for disease control and conservations of the endangered crocodile lizards and other reptiles. In addition, this study indicated that mNGS of lesions could be used to detect the pathogens in animals with benefits in speed and convenient.

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