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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 320: 124569, 2024 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-38878719

RESUMO

Unfertilized duck eggs not removed prior to incubation will deteriorate quickly, posing a risk of contaminating the normally fertilized duck eggs. Thus, detecting the fertilization status of breeding duck eggs as early as possible is a meaningful and challenging task. Most existing work usually focus on the characteristics of chicken eggs during mid-term hatching. However, little attention has been paid to the detection for duck eggs prior to incubation. In this paper, we present a novel hybrid deep learning detection framework for the fertilization status of pre-incubation duck eggs, termed CVAE-DF, based on visible/near-infrared (VIS/NIR) transmittance spectroscopy. The framework comprises the encoder of a convolutional variational autoencoder (CVAE) and an improved deep forest (DF) model. More specifically, we first collected transmittance spectral data (400-1000 nm) of 255 duck eggs before hatching. The multiplicative scatter correction (MSC) method was then used to eliminate noise and extraneous information of the raw spectral data. Two efficient data augmentation methods were adopted to provide sufficient data. After that, CVAE was applied to extract representative features and reduce the feature dimension for the detection task. Finally, an improved DF model was employed to build the classification model on the enhanced feature set. The CVAE-DF model achieved an overall accuracy of 95.94 % on the test dataset. These experimental results in terms of four metrics demonstrate that our CVAE-DF method outperforms the traditional methods by a significant margin. Furthermore, the results also indicate that CVAE holds great promise as a novel feature extraction method for the VIS/NIR spectral analysis of other agricultural products. It is extremely beneficial to practical engineering.


Assuntos
Aprendizado Profundo , Patos , Fertilização , Espectroscopia de Luz Próxima ao Infravermelho , Animais , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Fertilização/fisiologia , Óvulo/química
2.
Front Zool ; 21(1): 12, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38632631

RESUMO

BACKGROUND: Energy and time allocation in seabirds differ between consecutive stages of breeding given various requirements of particular phases of the reproductive period. Theses allocations may also be sex-specific considering differential energetic or nutritional requirements of males and females and/or sexual segregation in foraging niches and/or areas. In this study we investigated the foraging ecology of an Arctic, zooplanktivorous seabird, the little auk Alle alle during the pre-laying period using remote sensing of the environment and GPS-TDR loggers deployed on birds. We compared foraging trips range and habitats of birds with other stages of the breeding period and between sexes. RESULTS: We found that little auks during the pre-laying period foraged exclusively in cold sea surface temperature zones (with temperatures < 5 ºC) but in various sea depth zones. They dived to similar depths ranging from -4.0 to -10.9 m, exploring various thermal microhabitats (with mean temperatures values ranging from 2.2 °C in Shelf sea depth zone to 5.9 °C in Deep sea depth zone). The majority of foraging trips and dives characteristics were similar to subsequent phases of breeding. However, home ranges during the pre-laying trips were wider compared to the incubation period. As expected, females exhibited wider foraging niches compared to males (wider range of sea surface temperature and sea depth in foraging locations), which could be explained by sex specific energetic and/or nutritional requirements (females producing an egg). We also delineated local foraging areas important for little auks during their whole breeding season. Protection of these areas is crucial for sustaining the local marine biodiversity. CONCLUSIONS: We found that little auks females during the pre-laying period explored wider foraging niches compared to males. These differences may be attributed to sex-specific nutritional or/and energetical constraints at this stage of breeding. The results of this study also emphasize the importance of shelf Arctic-type water masses as the foraging areas for little auks during successive stages of breeding.

3.
Materials (Basel) ; 16(20)2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37895637

RESUMO

The application of biochar as an additive to enhance the anaerobic digestion (AD) of biomass has been extensively studied from various perspectives. This study reported, for the first time, the influence of biochar incubation in the inoculum on the anaerobic fermentation of glucose in a batch-type reactor over 20 days. Three groups of inoculum with the same characteristics were pre-mixed once with biochar for different durations: 21 days (D21), 10 days (D10), and 0 days (D0). The BC was mixed in the inoculum at a concentration of 8.0 g/L. The proportion of the inoculum and substrate was adjusted to an inoculum-to-substrate ratio of 2.0 based on the volatile solids. The results of the experiment revealed that D21 had the highest cumulative methane yield, of 348.98 mL, compared to 322.66, 290.05, and 25.15 mL obtained from D10, D0, and the control, respectively. Three models-modified Gompertz, first-order, and Autoregressive Integrated Moving Average (ARIMA)-were used to interpret the biomethane production. All models showed promising fitting of the cumulative biomethane production, as indicated by high R2 and low RMSE values. Among these models, the ARIMA model exhibited the closest fit to the actual data. The biomethane production rate, derived from the modified Gompertz Model, increased as the incubation period increased, with D21 yielding the highest rate of 31.13 mL/gVS. This study suggests that the application of biochar in the anaerobic fermentation of glucose, particularly considering the short incubation period, holds significant potential for improving the overall performance of anaerobic digestion.

4.
Bioresour Technol ; 346: 126644, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34973402

RESUMO

This short communication analyzed the effects of lignin-derived phenolic acid compounds on cellulase. Vanillic acid, syringic acid, ferulic acid, and isovanillic acid improved cellulase specific activity and saccharification efficiency. In the enzymatic hydrolysis process, the promotion effect of phenolic acid was concentration-dependent. The effect of low concentration of phenolic acids (less than 5 mM) was negligible. After pre-incubating 1 g cellulase with 5 mmol phenolic acid, FPase-specific activity, CMCase-specific activity, and pNPGase-specific activity increased by 57.06%, 136.79%, and 110.61%, respectively. After digestion with pre-incubated cellulase, the saccharification efficiency of phosphoric acid-swollen cellulose increased by 45.13%. Pre-incubation with phenolic acid improved the saccharification efficiency of cellulase. It might be helpful to enhance the comprehensive utilization capacity of lignin-derived compounds.


Assuntos
Celulase , Celulose , Hidrólise , Hidroxibenzoatos/farmacologia , Lignina
5.
Anal Chim Acta ; 1189: 339187, 2022 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-34815032

RESUMO

African swine fever (ASF) is a swine viral disease that could cause highly contagious and extremely high mortality, causing huge economic losses to the pig industry. As there is currently no vaccine and effective treatment methods. Therefore, early monitoring is one of the most important solutions to prevent and control ASF. In this study, the dual QDM recombinant virus protein 30 and 54 (P30 and P54) probes and pre-incubation in vitro were proposed for the first time as QDM based-ASFV immunosensor (QAIS) for the ultra-sensitive quantitative detection of ASFV antibodies in serum. In the range from serum dilution of 1:1000 to 1:64000, it showed a good linear relationship (R2 = 0.9947), and its detection sensitivity was 1:64000 dilution. Compared with commercial enzyme-linked immunosorbent assay (ELISA) and colloidal gold immunochromatographic strip (CGICS), its detection sensitivity was improved by at least one order of magnitude and four orders of magnitude respectively. In addition, the whole ASFV antibody screening test can be completed in 25 min with simple operation. The performance and practicability of the established QAIS sensor have been verified by ASF-ELISA kit, and its coincidence rate was as high as 98.7% in 151 clinical samples. We firmly believe that the proposed QAIS sensor could potentially be applied to point-of-care testing (POCT) for quantitative ASFV antibody in pig farms.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Técnicas Biossensoriais , Febre Suína Africana/diagnóstico , Animais , Imunoensaio , Suínos , Proteínas Virais
6.
Int J Mol Sci ; 24(1)2022 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-36614160

RESUMO

Acinetobacter baumannii is a dangerous hospital pathogen primarily due to its ability to form biofilms on different abiotic and biotic surfaces. The present study investigated the effect of riboflavin- and chlorophyllin-based antimicrobial photodynamic therapy, performed with near-ultraviolet or blue light on the viability of bacterial cells in biofilms and their structural stability, also determining the extent of photoinduced generation of intracellular reactive oxygen species as well as the ability of A. baumannii to form biofilms after the treatment. The efficacy of antimicrobial photodynamic therapy was compared with that of light alone and the role of the photosensitizer type on the photosensitization mechanism was demonstrated. We found that the antibacterial effect of riboflavin-based antimicrobial photodynamic therapy depends on the ability of photoactivated riboflavin to generate intracellular reactive oxygen species but does not depend on the concentration of riboflavin and pre-incubation time before irradiation. Moreover, our results suggest a clear interconnection between the inactivation efficiency of chlorophyllin-based antimicrobial photodynamic therapy and the sensitivity of A. baumannii biofilms to used light. In summary, all the analyzed results suggest that riboflavin-based antimicrobial photodynamic therapy and chlorophyllin-based antimicrobial photodynamic therapy have the potential to be applied as an antibacterial treatment against A. baumannii biofilms or as a preventive measure against biofilm formation.


Assuntos
Acinetobacter baumannii , Anti-Infecciosos , Fotoquimioterapia , Espécies Reativas de Oxigênio/farmacologia , Anti-Infecciosos/farmacologia , Antibacterianos/farmacologia , Fotoquimioterapia/métodos , Biofilmes , Riboflavina/farmacologia
7.
Eur J Clin Microbiol Infect Dis ; 40(4): 699-705, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33034779

RESUMO

Delayed entry of patient blood culture samples into a microbial detection system is unavoidable at times, due to off-shift staffing or transporting samples to centralized laboratories. Pre-incubation time and temperature of blood culture bottles are the most critical factors impacting recovery and detection of microorganisms. A total of 1377 BACT/ALERT® (BTA) Fastidious Antimicrobial Neutralization (FAN® PLUS) bottles (FA PLUS, FN PLUS, and PF PLUS) were tested after delayed entry times of 24 and 36 h at 20-25 °C (room temperature, RT) prior to loading into the BACT/ALERT® VIRTUO® microbial detection system (VIRTUO). Clinically relevant organisms were inoculated into bottles with 5-84 colony forming units (CFU) per bottle, and human blood (0 to 10 mL), and then loaded into the VIRTUO. When bottles were loaded without delay, a mean time to detection (TTD) of 9.6 h was observed. For delayed bottles, the TTD reported by the VIRTUO was added to the 24-h and 36-h delay times and resulted in average time to results of 32.5 h and 42.5 h, respectively. The FAN PLUS bottles in conjunction with the VIRTUO produced acceptable results when delays up to 24 h at 20-25 °C occur in loading.


Assuntos
Técnicas Bacteriológicas/métodos , Hemocultura/métodos , Manejo de Espécimes , Meios de Cultura , Humanos , Fatores de Tempo
8.
Sci Total Environ ; 749: 141468, 2020 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-32827816

RESUMO

Many environmental pollutants pose a toxicological hazard only after metabolic activation. In vitro bioassays using cell lines or bacteria have often no or reduced metabolic activity, which impedes their use in the risk assessment. To improve the predictive capability of in vitro assays, external metabolization systems like the liver S9 fraction are frequently combined with in vitro toxicity assays. While it is typical for S9 fractions that samples and testing systems are combined in the same exposure system, we propose to separate the metabolism step and toxicity measurement. This allows for a modular combination of metabolic activation by enzymes isolated from rat liver (S9) or a biotechnological alternative (ewoS9R) with in vitro bioassays that lack metabolic capacity. Benzo(a)pyrene and 2-aminoanthracene were used as model compounds to optimize the conditions for the S9 metabolic degradation/activation step. The Ames assay with Salmonella typhimurium strains TA98 and TA100 was applied to validate the set-up of decoupling the S9 activation/metabolism from the bioassay system. S9 protein concentration of 0.25 mgprotein/mL, a supplement of 0.13 mM NADPH and a pre-incubation time of 100 min are recommended for activation of samples prior to dosing them to in vitro bioassays using the regular dosing protocols of the respective bioassay. EwoS9R performed equally well as Moltox S9, which is a step forward in developing true animal-free in vitro bioassays. After pre-incubation with S9 fraction, chemicals induced bacteria revertants in both the TA98 and the TA100 assay as efficiently as the standard Ames assay. The pre-incubation of chemicals with S9 fraction could serve for a wide range of cellular in vitro assays to efficiently combine activation and toxicity measurement, which may greatly facilitate the application of these assays for chemical hazard assessment and monitoring of environmental samples.


Assuntos
Mutagênicos , Salmonella typhimurium , Animais , Biotransformação , Extratos Celulares/farmacologia , Fígado , Microssomos Hepáticos/metabolismo , Testes de Mutagenicidade , Ratos , Salmonella typhimurium/genética
9.
World J Microbiol Biotechnol ; 36(2): 27, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31997003

RESUMO

A phosphate solubilizing bacterium ZB was isolated from the rhizosphere soil of Araucaria, which falls into the species Pantoea agglomerans. Optimization for phosphate solubilization by strain ZB was performed. At optimum culture conditions, the isolate showed great ability of solubilizing different insoluble inorganic phosphate sources viz. Ca3(PO4)2 (TCP), Hydroxyapatite (HP), CaHPO4, AlPO4, FePO4 along with rock phosphates (RPs). Inoculation with planktonic cells was found to enhance dissolved phosphorous as compared to that achieved by symplasma inoculation. Besides inoculation with different status of cells, pre-incubation could also exert a great effect on phosphate solubilization ability of P. agglomerans. When isolate ZB was cultured with glucose as carbon sources, phosphorous was more efficiently dissolved from HP and RP without pre-incubation in comparison to that obtained with pre-cultivation. Pre-cultivation, however, was more suitable for P solubilization than no pre-cultivation when bacteria were grown with xylose. A positive correlation was detected between the production of organic acids and phosphate solubilization. P. agglomerans ZB possessed many plant growth promotion traits such as N2 fixation and production of indole 3-acetic acid, phytase, alkaline phosphatase. Pot experiment showed inoculation with single isolate ZB or biofertilizer prepared from semi-solid fermentation of isolate ZB with spent mushroom substrate (SMS) compost could enhance plant growth with respect to number of leaves, plant leave area, stem diameter, root length, root dry mass, shoot dry mass and biomass when compared to the abiotic control, revealing strain ZB could be a promising environmental-friendly biofertilizer to apply for agricultural field.


Assuntos
Araucaria/microbiologia , Pantoea/isolamento & purificação , Fosfatos/química , Carbono/química , Fermentação , Glucose/química , Fixação de Nitrogênio , Pantoea/metabolismo , Rizosfera , Microbiologia do Solo , Solubilidade
10.
Mikrochim Acta ; 187(1): 10, 2019 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-31797114

RESUMO

A lateral-flow immunochromatographic assay with excellent sensitivity and wide application potential is described. The bovine serum albumin (BSA) antibody was immobilized in the test line for universality, and preincubation was introduced for high method sensitivity. Carboxy-modified CdSe/ZnS core-shell nanoparticles were used as label, and the fluorescence peaking at 605 nm was detected. The fluorescence in the test line was negative against the relevant analyte content. The chloramphenicol (CAP) and the aflatoxin M1 (AFM1) in milk were detected using the same strip to validate the universality. After optimization, the detection limit for CAP is 10 pg·mL-1, which is three times less that of a conventional assay (30 pg·mL-1). The detection limit for AFM1 was 6 pg·mL-1, which was 13 times less than that of a conventional assay (8 pg·mL-1). The method was applied in the analysis of spiked milk samples. The performance was compared with that of the commercial ELISA kit, and good agreement was observed. Graphical abstractSchematic representation of the universal and sensitive combined immunochromatographic assay (USICA) and conventional immunochromatographic assay (TICA) of chloramphenicol (CAP) and aflatoxin M1.


Assuntos
Aflatoxina M1/análise , Anticorpos Imobilizados/química , Compostos de Cádmio/química , Cloranfenicol/análise , Imunoensaio/métodos , Nanopartículas/química , Compostos de Selênio/química , Sulfetos/química , Compostos de Zinco/química , Aflatoxina M1/química , Anticorpos Imobilizados/imunologia , Cloranfenicol/química , Limite de Detecção , Soroalbumina Bovina/imunologia
11.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-796585

RESUMO

Objective@#To establish a simple method for isolation, purification and cultivation of primary retinal microvascular pericytes (RMPs) from mice.@*Methods@#Retinas were isolated from mice following with mechanical morcel, enzymatic digestion and filtration.The retinal fragments were incubated with low glucose DMEM with 20% fetal bovine serum after 24 hours pre-incubation.Differential digestion was used for purification of primary RMPs.Morphological examination of cells was performed by phase contrast microscopy, and further characterization was analyzed by immunocytochemistry.Functional assay was evaluated by the pericytes-endothelial cells (ECs) co-culture system.The treatment and use of experimental animals followed the regulations on the administration of experimental animals promulgated by the state science and technology commission.@*Results@#Cells migrated out of fragments after 24 hours of incubation, and developed into small or large colonies gradually.The cells and their subpassages presented typical pericyte morphology with large irregular triangular cell bodies and multiple long processes.No contact inhibition was observed.Most cells uniformly expressed the cellular markers α-smooth muscle actin (α-SMA) and platelet-derived growth factor receptor-β (PDGFR-β), a few cells expressed the cellular markers glial fibrillary acidic protein (GFAP), but no cell expressed von Willebrand factor (vWF). The purity rate of RMPs was up to 97%.In the co-culture system, RMPs directly contacted with ECs to form the capillary-like cords in vitro.@*Conclusions@#A simple method for the isolation, purification cultivation of mouse RMPs is established, and active RMPs can be readily obtained by this method.

12.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-790160

RESUMO

Objective To establish a simple method for isolation, purification and cultivation of primary retinal microvascular pericytes ( RMPs) from mice. Methods Retinas were isolated from mice following with mechanical morcel,enzymatic digestion and filtration. The retinal fragments were incubated with low glucose DMEM with 20% fetal bovine serum after 24 hours pre-incubation. Differential digestion was used for purification of primary RMPs. Morphological examination of cells was performed by phase contrast microscopy, and further characterization was analyzed by immunocytochemistry. Functional assay was evaluated by the pericytes-endothelial cells ( ECs) co-culture system. The treatment and use of experimental animals followed the regulations on the administration of experimental animals promulgated by the state science and technology commission. Results Cells migrated out of fragments after 24 hours of incubation, and developed into small or large colonies gradually. The cells and their subpassages presented typical pericyte morphology with large irregular triangular cell bodies and multiple long processes. No contact inhibition was observed. Most cells uniformly expressed the cellular markers α-smooth muscle actin (α-SMA) and platelet-derived growth factor receptor-β( PDGFR-β) ,a few cells expressed the cellular markers glial fibrillary acidic protein ( GFAP) ,but no cell expressed von Willebrand factor ( vWF) . The purity rate of RMPs was up to 97%. In the co-culture system,RMPs directly contacted with ECs to form the capillary-like cords in vitro. Conclusions A simple method for the isolation, purification cultivation of mouse RMPs is established, and active RMPs can be readily obtained by this method.

13.
Sensors (Basel) ; 18(11)2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30445792

RESUMO

A simple approach was proposed to decrease the detection limit of sandwich lateral flow immunoassay (LFIA) by changing the conditions for binding between a polyvalent antigen and a conjugate of gold nanoparticles (GNPs) with antibodies. In this study, the potato virus Y (PVY) was used as the polyvalent antigen, which affects economically important plants in the Solanaceae family. The obtained polyclonal antibodies that are specific to PVY were characterized using a sandwich enzyme-linked immunosorbent assay (ELISA) and surface plasmon resonance (SPR). For LFIA, the antibodies were conjugated with GNPs with a diameter of 17.4 ± 1.0 nm. We conducted LFIAs using GNP conjugates in a dried state on the test strip and after pre-incubation with a sample. Pre-incubating the GNP conjugates and sample for 30 s was found to decrease the detection limit by 60-fold from 330 ng∙mL-1 to 5.4 ng∙mL-1 in comparison with conventional LFIA. The developed method was successfully tested for its ability to detect PVY in infected and uninfected potato leaves. The quantitative results of the proposed LFIA with pre-incubation were confirmed by ELISA, and resulted in a correlation coefficient of 0.891. The proposed approach is rapid, simple, and preserves the main advantages of LFIA as a non-laboratory diagnostic method.


Assuntos
Anticorpos/imunologia , Antígenos/isolamento & purificação , Técnicas Biossensoriais , Potyvirus/isolamento & purificação , Anticorpos/química , Antígenos/imunologia , Ensaio de Imunoadsorção Enzimática , Imunoconjugados/química , Limite de Detecção , Nanopartículas Metálicas/química , Potyvirus/patogenicidade , Solanum tuberosum/virologia , Ressonância de Plasmônio de Superfície
14.
Ying Yong Sheng Tai Xue Bao ; 29(6): 1999-2006, 2018 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-29974711

RESUMO

Soil nitrogen forms and contents are of great importance in ecological studies. The storage methods of soil samples have great effects on the accuracy of determination of nitrogen contents. We aimed to select a reasonable storage method for soil samples with forest soil of Castanopsis faberi fore-st at Wanmulin Nature Reserve in Jian'ou City as an example. The contents of soil ammonium, nitrate, total nitrogen, soluble organic nitrogen, amino acid nitrogen and microbial biomass nitrogen were measured in soil samples under the storage conditions of different temperature (at 25, 4 and -20 ℃) and different times (0, 7 and 30 days). The nitrogen contents during the process of cultivating under the room temperature after being frozen were also measured. The results showed that the contents of all nitrogen forms except for amino acid nitrogen were increased in the soil samples that stored at the room temperature for seven days. There were no significant differences between the contents of all the tested nitrogen forms in the refrigerated or frozen samples and the fresh soil samples. The changes of nitrogen content in soil samples at refrigerated and frozen storage were more stable than those at room temperature storage. The low temperature storage could stimulate soil mineralization. Hence, after stored for 30 days, contents of all the tested nitrogen forms in the refri-gerated and frozen storage soil samples were significantly higher than those in the fresh samples except for the soluble organic nitrogen, whereas there was no significant difference between the refrigerated and frozen storage methods. Therefore, fresh samples should be promptly processed when taken back to the laboratory. If the samples needed to storage, it should not be stored more than half a month. If the samples need a longer storage time, it must be placed in lower temperature (at -40 or -80 ℃). Pre-incubation treatment was required when the low temperature storage soil sample was subjected to an experiment. In the process of pre-incubation, the contents of all the tested nitrogen form in soil samples gradually approached the level of fresh soil sample with the increases of incubation time except for that of nitrate which decreased firstly and then increased rapidly. After incubation for about one week, the nitrogen content of soil sample returned to the level that was close to that of the fresh soil. In combination with studies previously reported, soil samples collected from field and air dried samples needed a pre-incubation for 5-14 days, and the pre-incubation time for the cold storage sample should not be less than one week.


Assuntos
Nitrogênio , Microbiologia do Solo , Solo/química , Florestas , Temperatura
15.
Environ Monit Assess ; 190(2): 94, 2018 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-29372330

RESUMO

Global generation of human hair waste and its disposal at landfills could contribute to the leaching of nitrates into ground water. High concentrations of nitrogen (N) and other elements suggest that the waste could be a source of plant nutrients and differences in ethnic hair types could affect nutrient release and fertiliser value. The objective of this study was to determine the effects of hair type, as an N source, and pre-incubation time on dry-matter yield, nutrient uptake by spinach (Spinacia oleracea L.) and residual soil nutrients. Salons in Pietermaritzburg provided bulk African and Caucasian hair waste, without distinguishing age, sex, health status or livelihood of the individuals. The hair waste was analysed for elemental composition. A pot experiment was set up under glasshouse conditions. The hair waste was incorporated (400 kg N ha-1) into a loamy oxisol and pre-incubated for 0, 28, 56 and 84 days before planting spinach. Potassium (K) and phosphorus (P) were corrected to the same level for all treatments. Spinach seedlings were then cultivated for 6 weeks. Shoot dry-matter and the uptake of all nutrients, except P, were increased by the pre-incubation of hair. African hair pre-incubated for 28 days resulted in greater dry-matter, N, K, Mn and S uptake than Caucasian hair. Increasing pre-incubation resulted in a decline in the residual soil pH and exchangeable K. The findings suggested that pre-incubation improves the N fertiliser value of hair and that African hair has greater value than Caucasian hair when pre-incubated for a short period.


Assuntos
Fertilizantes/análise , Cabelo , Nitrogênio/análise , Resíduos , Monitoramento Ambiental , Humanos , Nitratos/análise , Fósforo/análise , Potássio/análise , Solo/química , Poluentes do Solo/análise , África do Sul , Spinacia oleracea , Instalações de Eliminação de Resíduos
16.
Environ Mol Mutagen ; 57(9): 687-705, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27862311

RESUMO

"Ames" bacterial mutation tests are widely performed for evaluation and registration of new materials including industrial chemicals, agrochemicals, medical devices, pharmaceuticals, pharmaceutical impurities and other materials. Tests are used to predict their potential long-term adverse health effects (including carcinogenicity). Given their importance, pre-screening 'miniaturized' versions have been developed which allow higher throughput and use less test material, including the widely-employed 24-well micro-Ames (µAmes) test which uses 20 times less material. However, little quantitative information has been published on the methodology or sensitivity of this system. We describe methods and results used in direct comparisons of the sensitivity of micro and standard systems using the same cultures, formulations, etc. Initial testing utilized the plate incorporation method and, later, the pre-incubation method. In a subsequent phase of testing, a four-way direct comparison was made between the pre-incubation and plate incorporation methods in both systems using some direct-acting mutagens. Tests used only those strain/S9/chemical combinations where a response was expected. Historical control results accumulated during testing are also presented. Spontaneous and induced revertant colony counts for the µAmes system were consistently proportionate and approximately 1/20th those for the standard Ames test. Sensitivities of the two systems were found to be nearly identical in almost all cases for a wide variety of weak and strong inorganic and organic mutagens. Standardized procedures and increased reliability of the estimate of the background revertant frequency in the µAmes system means that the two systems give equivalent results and are expected to be highly predictive of one another. Environ. Mol. Mutagen. 57:687-705, 2016. © 2016 Wiley Periodicals, Inc.


Assuntos
Testes de Mutagenicidade/métodos , Mutagênicos/toxicidade , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética , Relação Dose-Resposta a Droga , Limite de Detecção , Sensibilidade e Especificidade
17.
Biopharm Drug Dispos ; 37(8): 479-490, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27603548

RESUMO

Cyclosporine A, an inhibitor of hepatic organic anion transporting polypeptides (OATPs), reportedly increased plasma concentrations of probe substrates, although its maximum unbound blood concentrations were lower than the experimental half-maximal inhibitory (IC50 ) concentrations. Pre-incubation with cyclosporine A in vitro before simultaneous incubation with probes has been reported to potentiate its inhibitory effects on recombinant human OATP-mediated probe uptake. In the present study, the effects of cyclosporine A and rifampicin on recombinant cynomolgus monkey OATP-mediated pitavastatin uptake were investigated in pre- and simultaneous incubation systems. Pre-incubation with cyclosporine A, but not with rifampicin, decreased the apparent IC50 values on recombinant cynomolgus monkey OATP1B1- and OATP1B3-mediated pitavastatin uptake. Application of the co-incubated IC50 values toward R values (1 + [unbound inhibitor]inlet to the liver, theoretically maximum /inhibition constant) in static models, 1.1 in monkeys and 1.3 in humans, for recombinant cynomolgus monkey and human OATP1B1-mediated pitavastatin uptake might result in the poor prediction of drug interaction magnitudes. In contrast, the lowered IC50 values after pre-incubation with cyclosporine A provided better prediction with R values of 3.9 for monkeys and 2.7 for humans when the estimated maximum cyclosporine A concentrations at the inlet to the liver were used. These results suggest that the enhanced inhibitory potential of perpetrator medicines by pre-incubation on cynomolgus monkey OATP-mediated pitavastatin uptake in vitro could be of value for the precise estimation of drug interaction magnitudes in silico, in accordance with the findings from pre-administration of inhibitors on pitavastatin pharmacokinetics validated in monkeys. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Antifúngicos/metabolismo , Ciclosporina/metabolismo , Inibidores de Hidroximetilglutaril-CoA Redutases/metabolismo , Transportador 1 de Ânion Orgânico Específico do Fígado/biossíntese , Transportadores de Ânions Orgânicos Sódio-Independentes/biossíntese , Quinolinas/metabolismo , Animais , Antifúngicos/farmacologia , Transporte Biológico/fisiologia , Ciclosporina/farmacologia , Relação Dose-Resposta a Droga , Interações Medicamentosas/fisiologia , Células HEK293 , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Macaca fascicularis , Quinolinas/farmacologia , Membro 1B3 da Família de Transportadores de Ânion Orgânico Carreador de Soluto
18.
J Microbiol Immunol Infect ; 49(1): 97-103, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24767420

RESUMO

BACKGROUND/PURPOSE: Tuberculosis (TB) is a crucial health problem. Prevention of the disease requires rapid diagnosis. Rapid liquid culture systems, nucleic acid amplification tests, and high-performance liquid chromatography (HPLC) are among the rapid tests used for detecting Mycobacterium species. However, these tests are expensive and require extensive equipment and expertise, which is hardly affordable in resource-poor countries. Although direct microscopy is performed routinely as an initial step for detection of the bacteria, it is not sufficiently sensitive. As a result, we thought of establishing a low-cost immunological test that can potentially replace direct microscopy with higher sensitivity and specificity. METHODS: The assay is based on pre-incubation of biotinylated rabbit antibody against Antigen 60 (A60) with a solution containing Bacillus Calmette-Guérin (BCG) or Mycobacterium tuberculosis (MTB) followed by incubation with a streptavidin-alkaline phosphatase (STA-ALP) conjugate. The test is devised in enzyme-linked immunosorbent assay (ELISA) and non-ELISA formats, therefore it does not require extensive facilities and expertise. RESULTS: The ELISA format showed a 100-fold improvement in the lower detection limit of BCG compared with direct microscopy. With the non-ELISA formats, there was a 2- and 16-fold improvement for the cartridge assay and the microfuge tube assay, respectively. CONCLUSION: In conclusion, we successfully detected BCG and MTB in solution using the new immunological method. Our results are very promising and the new immunological method could potentially replace direct microscopy with higher sensitivity and specificity.


Assuntos
Técnicas Bacteriológicas/métodos , Imunoensaio/métodos , Mycobacterium/isolamento & purificação , Tuberculose/diagnóstico , Sensibilidade e Especificidade
19.
Poult Sci ; 94(9): 2257-65, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26217026

RESUMO

Pre-incubation egg storage is a necessity for the poultry industry. This study evaluated the effects of pre-incubation storage length of broiler eggs on hatchability, 1-day-old chick quality, subsequent performance, and immunocompetence. To this end, a total of 360 hatching eggs were stored for 4, 12, or 16 d prior to incubation. Hatchability and chick quality were assessed at hatch, and growth performance and immunocompetence parameters were assessed during a 35 d rearing period. Hatchability of set and fertile eggs, and embryonic mortality, were not affected by egg storage. On the contrary, 1-day-old chick BW and length were linearly negatively correlated with egg storage length (P-linear<0.05). Nevertheless, BW corrected for egg weight prior to setting was unaffected, and corrected chick length was positively affected by storage length. One-day-old chick Tona score, navel quality, and post-hatch growth performance (BW at 7 and 35 d, cumulative feed intake, and feed conversion ratio at 35 d) were unaffected by egg storage (P, P-linear>0.05). Lymphoid organ weights at 2 and 35 d, the titre of maternal anti-NDV antibodies, most of the thymocyte subpopulations defined by CD3, CD4, and CD8 cell surface expression in the thymus of 2-d-old chicks, cellular responses to the PHA skin test, humoral responses to primary SRBC, and NDV immunizations were also not influenced by length of storage (P, P-linear>0.05). On the contrary, the length of egg storage was found to negatively influence the abundance of CD3+CD4-CD8- thymocytes that represent the majority of γδ-T cells in the thymus of 2-day-old chicks, as well as the humoral response to booster NDV immunization of the birds. In brief, pre-incubation storage of broiler hatching eggs for up to 16 d did not affect most developmental and growth parameters investigated, except for BW and length at hatch. Egg storage was found to suppress some aspects of the immunocompetence of the birds, particularly aspects of acquired immunity.


Assuntos
Criação de Animais Domésticos/normas , Galinhas/fisiologia , Imunocompetência , Óvulo/fisiologia , Animais , Embrião de Galinha/embriologia , Embrião de Galinha/fisiologia , Galinhas/crescimento & desenvolvimento , Galinhas/imunologia , Longevidade , Distribuição Aleatória
20.
Anim Reprod Sci ; 159: 141-7, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26119142

RESUMO

Standardization of fertilization protocols for sterlet Acipenser ruthenus is crucial for improving reproductive techniques and for conservation purposes. Our objectives were to determine the number of sperm (tested 430,000:1, 43,000:1, 4300:1, 430:1 sperm to egg) required to fertilize eggs and explore how pre-incubation of eggs in freshwater for 0min, 0.5min, 1min, and 10min interacts with different sperm ratios. Fertilization success ranged from 29.7% at 430:1 to 84.2% at 430,000:1. Pre-incubation time had no effect on fertilization success at 430,000:1 and 43,000:1 sperm to egg ratios, while it was significant at the 4300:1 and 430:1 ratios. The use of adequate experimental suboptimal sperm to egg ratio revealed a positive effect of pre-incubation time, such that at the 430:1 ratio, 0.5min pre-incubation increased the fertilization rate than 10min. At 0min pre-incubation the proportion of fertilized eggs increased at the 430,000:1 ratio, while at 1min fertilization increased at the 4300:1 ratio. At the 10min pre-incubation time, fertilization increased at the 43,000:1 ratio. Moreover, at the 0.5min pre-incubation time, the 43,000:1 ratio increased the fertilization rate than the 430:1 ratio. Generally, for 430:1 ratio, the fertilization rate is lower than in control. Transmission electron microscopy showed that pre-incubation of eggs in water for <10min does not trigger a cortical reaction or the formation of a perivitelline space. Results suggest that with a low sperm to egg ratio 0.5 to 1min pre-incubation of eggs in freshwater prior to fertilization can enhance fertilization rate of sterlet.


Assuntos
Fertilização/fisiologia , Peixes/fisiologia , Óvulo/fisiologia , Espermatozoides/fisiologia , Animais , Fertilização in vitro/veterinária , Masculino , Contagem de Espermatozoides , Fatores de Tempo , Água
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