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151.
Over 182 million confirmed cases of COVID-19 and more than 4 million deaths have been reported to date around the world. It is essential to identify broad-spectrum antiviral agents that may prevent or treat infections by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) but also by other coronaviruses that may jump the species barrier in the future. We evaluated the antiviral selectivity of griffithsin and sulfated and non-sulfated polysaccharides against SARS-CoV-1 and SARS-CoV-2 using a cytotoxicity assay and a cell-based pseudoviral model. The half-maximal cytotoxic concentration (CC50) and half-maximal effective concentration (EC50) were determined for each compound, using a dose-response-inhibition analysis on GraphPad Prism v9.0.2 software (San Diego, CA, USA). The therapeutic index (TI = CC50/EC50) was calculated for each compound. The potential synergistic, additive, or antagonistic effect of different compound combinations was determined by CalcuSyn v1 software (Biosoft, Cambridge, UK), which estimated the combination index (CI) values. Iota and lambda carrageenan showed the most potent antiviral activity (EC50 between 3.2 and 7.5 µg/mL). Carrageenan and griffithsin combinations exhibited synergistic activity (EC50 between 0.2 and 3.8 µg/mL; combination index <1), including against recent SARS-CoV-2 mutations. The griffithsin and carrageenan combination is a promising candidate to prevent or treat infections by SARS-CoV-1 and SARS-CoV-2.  相似文献   
152.
Cowpea seed samples from South Africa and Benin were analyzed for seed mycoflora. Fusariumspecies detected were F. equiseti, F. chlamydosporum, F. graminearum, F. proliferatum, F. sambucinum, F. semitectum, and F. subglutinans. Cowpea seed from South Africa and Benin and F. proliferatum isolates from Benin, inoculated onto maize patty medium, were analyzed for fumonisin production. Samples were extracted with methanol/water and cleaned up on strong anion exchange solid phase extraction cartridges. HPLC with precolumn derivatization using o-phthaldialdehyde was used for the detection and quantification of fumonisins. Cowpea cultivars from South Africa showed the presence of fumonisin B(1) at concentrations ranging between 0.12 and 0.61 microg/g, whereas those from Benin showed no fumonisins. This is believed to be the first report of the natural occurrence of FB(1) on cowpea seed. Fumonisin B(1), B(2), and B(3) were produced by all F. proliferatum isolates. Total fumonisin concentrations were between 0.8 and 25.30 microg/g, and the highest level of FB(1) detected was 16.86 microg/g.  相似文献   
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Gastric surgery is commonly performed to remove foreign bodies and correct gastric dilatation-volvulus and is less commonly performed to treat gastric ulceration or erosion, neoplasia, and benign gastric outflow obstruction. Intestinal surgery, although commonly performed by veterinarians, should never be considered routine. The most common procedures of the small intestinal tract performed in dogs and cats include enterotomy and resection/anastomosis. Surgery of the large intestine is indicated for lesions causing obstruction, perforations, colonic inertia, or chronic inflammation.  相似文献   
155.

Key message The application of the ITOC model allows the estimation of available biomass potentials from forests on the basis of National Forest Inventory data. The adaptation of the model to country-specific situations gives the possibility to further enhance the model calculations.

Context

With the rising demand for energy from renewable sources, up-to-date information about the available amount of biomass on a sustainable basis coming from forests became of interest to a wide group of stakeholders. The complexity of answering the question about amounts of biomass potentials from forests thereby increases from the regional to the European level.

Aims

The described ITOC model aims at providing a tool to develop a comparable data basis for the actual biomass potentials for consumption.

Methods

The ITOC model uses a harmonized net annual increment from the National Forest Inventories as a default value for the potential harvestable volume of timber. The model then calculates the total theoretical potential of biomass resources from forests. By accounting for harvesting restrictions and losses, the theoretical potential of biomass resources from forests is reduced and the actual biomass potentials for consumption estimated.

Results

The results from ITOC model calculations account for the difference between the amounts of wood measured in the forests and the actual biomass potentials which might be available for consumption under the model assumptions.

Conclusion

The gap between forest resource assessments and biomass potentials which are available for consumption can be addressed by using the ITOC model calculation results.
  相似文献   
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Garcinia kola is highly used as chew-stick for dental care in West Africa, but it is nearly commercially extinct in nature. To help find methods to increase rate and percentage of germination, we investigated its seed germination responses by using several collections and pre-treatments. Seeds processed from 6-week old green fruits did not germinate, whilst those of 10-week old partly-mature, at the intermediate stage through full development, germinated 46%. Seeds from orange mature fruits reached maximum 54–62% germination. Radicles emerged 6 weeks after sowing and normal germination with emergence of the primary single shoot growth occurred after 12 weeks. There was no significant difference (P ≥ 0.05) between germination responses of seeds from Ghana and Cote d’Ivoire. Seeds did not germinate when dried to below ca. 30% MC. De-coating seeds or soaking intact seeds in a 70% ethanol solution increased germination to 82–92%, and also increased germination rate; however germination was not uniform. Because difficulties in germinating these seeds stem from the physical presence of the seed coats and the slow growth of the embryos contained therein, we recommend that fresh seeds from mature fruits be de-coated and immediately sown in preferably, an aerated medium (e.g., sawdust) for cultivation.  相似文献   
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Milk is an easily digestible source of nutrients and bioactive factors, its composition reflects the neonate’s needs, and changes from colostrum to transitional and mature milk. Our objective was to measure milk fat, lactose, total carbohydrate, and protein content in parallel with global proteome of homogenate milk samples to characterize changes across the three phases of swine lactation. Milk samples were collected from multiparous sows (n = 9) on postnatal day 0 (D0; colostrum), 3 (D3; early transitional), 7 (D7; late transitional), and 14 (D14; mature). On D3, percent fat (16 ± 2.1) and lactose (3.8 ± 0.3) were higher (P < 0.05) than on D0 (10 ± 3.9 and 1.5 ± 0.3, respectively). Levels of fat and lactose were not different between D3 and D14. Percent total protein decreased (P < 0.05) between D0 (11 ± 2.1) and D3 (5 ± 0.7), but there was no significant change in percent protein between D3 and D14. Total carbohydrates increased (P < 0.05) between D3 (944 ± 353 µg/mL) and D14 (1,150 ± 462 µg/mL). Quantitative proteomic analysis using liquid chromatography tandem mass spectrometry (LC-MS/MS) of homogenate D0, D3, and D14 milk samples (n = 6) identified 772 protein groups which corresponded to 501 individual protein-coding genes. A total of 207 high confidence proteins were detected in n = 3 sows/day. Of the high confidence proteins, 81 proteins were common among all 3 days of lactation. Among the proteins that decreased between the days (false discovery rate; FDR < 0.05) were multiple apolipoproteins and XDH which decreased between D0 to D3. Proteins that increased across the days (FDR < 0.05) were complement factors and 14-3-3 proteins (YWHAQ, YWHAE). Our data provide a good characterization of milk proteome changes that likely reflect mammary function as well as the neonate’s phase-specific developmental needs. This data may be useful in developing approaches to enhance the health and welfare of swine.  相似文献   
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