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1.
Bull Environ Contam Toxicol ; 110(1): 40, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36627388

RESUMO

Predictive models were generated to evaluate the degree to which nine metals (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) were absorbed by the leaves, stems and roots of forage sorghum in growing media comprising soil admixed with poultry manure concentrations of 0, 10, 20, 30 and 40 g/kg. The data revealed that the greatest contents of the majority of the metals were evident in the roots rather than in the stems and leaves. A bioaccumulation factor (BAF) < 1 was calculated for Cr, Fe, Ni, Pb and Zn; BAF values for Co, Cu, Mn and Cd were 3.99, 2.33, 1.44 and 1.40, respectively, i.e., > 1. Translocation factor values were < 1 for all metals with the exception of Co, Cr and Ni, which displayed values of 1.20, 1.67 and 1.35 for the leaves, and 1.12, 1.23 and 1.24, respectively, for the stems. The soil pH had a negative association with metal tissues in plant parts. A positive relationship was observed with respect to plant metal contents, electrical conductivity and organic matter quantity. The designed models exhibited a high standard of data precision; any variations between the predicted and experimentally observed contents for the nine metals in the three plant tissue components were nonsignificant. Thus, it was concluded that the presented predictive models constitute a pragmatic tool to establish the safety from risk to human well-being with respect to growing forage sorghum when cultivating media fortified with poultry manure.


Assuntos
Metais Pesados , Poluentes do Solo , Sorghum , Animais , Humanos , Solo/química , Esterco , Metais Pesados/análise , Aves Domésticas , Cádmio , Chumbo , Poluentes do Solo/análise , Monitoramento Ambiental
3.
Environ Sci Pollut Res Int ; 29(44): 66507-66518, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35503150

RESUMO

Considering its richness in organic and inorganic mineral nutrients, the recycling of sewage sludge (SS) is highly considered as a soil supplement in agriculture. However, the fate of hazardous heavy metal accumulation in the crops cultivated in SS amended soils is always a source of concern. Since nanoparticles are widely recognized to reduce heavy metal uptake by crop plants; thus, the present experiment deals with okra (Abelmoschus esculentus L. Moench) cultivation under the combined application of SS and TiO2-nanoparticles (NPs). Triplicated pot experiments were conducted using different doses of SS and TiO2-NPs such as 0 g/kg SS (control), 50 g/kg SS, 50 g/kg SS + TiO2, 100 g/kg SS, and 100 g/kg SS + TiO2, respectively. The findings of this study indicated that among the doses of treatment combinations investigated, 100 g/kg SS + TiO2 showed a significant (p < 0.05) increase in the okra plant yield (287.87 ± 4.06 g/plant) and other biochemical parameters such as fruit length (13.97 ± 0.54 cm), plant height (75.05 ± 3.18 cm), superoxide dismutase (SOD: 110.68 ± 3.11 µ/mg), catalase (CAT: 81.32 ± 3.52 µ/mg), and chlorophyll content (3.12 ± 0.05 mg/g fwt.). Also, the maximum contents of six heavy metals in the soil and cultivated okra plant tissues (fruit, stem, and root regions) followed the order of Fe > Mn > Cu > Zn > Cr > Cd using the same treatment. Bioaccumulation and health risk assessment indicated that foliar application of TiO2-NPs significantly reduced the fate of heavy metal accumulation under higher doses of SS application. Therefore, the findings of this study suggested that the combined use of SS and TiO2-NPs may be useful in ameliorating the negative consequences of heavy metal accumulation in cultivated okra crops.


Assuntos
Abelmoschus , Metais Pesados , Nanopartículas , Cádmio , Catalase , Clorofila , Produtos Agrícolas , Metais Pesados/análise , Minerais , Esgotos , Solo , Superóxido Dismutase , Titânio
4.
J Fungi (Basel) ; 8(2)2022 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-35205866

RESUMO

The present study focused on the use of sewage sludge (SS) as a casing material amendment and the potential uptake of metal elements by the cultivated white button (Agaricus bisporus: MS-39) mushroom. Laboratory experiments were performed under controlled environmental conditions to grow A. bisporus on the composted wheat straw substrate for 50 days. Different treatments (0, 50, 100, 150, and 200 g/kg) of casing material were prepared by mixing garden and dried SS and applied on the mushroom substrate after proper sterilization. The results revealed that SS application was significant (p < 0.05) in accelerating mushroom yield with a biological efficiency of 65.02% for the mixing rate of 200 g/kg. Moreover, the maximum bioaccumulation of selected metal elements (Cu, Cr, Cd, Fe, Mn, and Zn) was observed using the same treatment. Additionally, the multiple regression models constructed for the uptake prediction of metal elements showed an acceptable coefficient of determination (R2 > 0.9900), high model efficiency (ME > 0.98), and low root mean square error (RMSE < 0.410) values, respectively. The findings of this study represent sustainable use of SS for the formulation of mushroom casing material contributing toward synergistic agro-economy generation and waste management.

5.
Geosci Front ; 13(6): 101373, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37521134

RESUMO

The novel coronavirus, SARS-CoV-2, which has caused millions of death globally is recognized to be unstable and recalcitrant in the environment, especially in the way it has been evolving to form new and highly transmissible variants. Of particular concerns are human-environment interactions and the handling and reusing the environmental materials, such as effluents, sludge, or biosolids laden with the SARS-CoV-2 without adequate treatments, thereby suggesting potential transmission and health risks. This study assesses the prevalence of SARS-CoV-2 RNA in effluents, sludge, and biosolids. Further, we evaluate the environmental, ecological, and health risks of reusing these environmental materials by wastewater/sludge workers and farmers. A systematic review of literature from the Scopus database resulted in a total of 21 articles (11 for effluents, 8 for sludge, and 2 for biosolids) that met the criteria for meta-analysis, which are then subdivided into 30 meta-analyzed studies. The prevalence of SAR-CoV-2 RNA in effluent and sludge based on random-effect models are 27.51 and 1012.25, respectively, with a 95% CI between 6.14 and 48.89 for the effluent, and 104.78 and 1019.71 for the sludge. However, the prevalence of SARS-CoV-2 RNA in the biosolids based on the fixed-effect model is 30.59, with a 95% CI between 10.10 and 51.08. The prevalence of SARS-CoV-2 RNA in environmental materials indicates the inefficiency in some of the treatment systems currently deployed to inactivate and remove the novel virus, which could be a potential health risk concern to vulnerable wastewater workers in particular, and the environmental and ecological issues for the population at large. This timely review portends the associated risks in handling and reusing environmental materials without proper and adequate treatments.

6.
Clin Exp Dermatol ; 47(4): 700-708, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34762763

RESUMO

BACKGROUND: Calciphylaxis is a life-threatening cutaneous ulcerative/necrotic disease characterized by vascular calcification/occlusion. It occurs most commonly in end-stage kidney disease (ESKD), known as uraemic calciphylaxis (UC) but can also occur in patients with chronic kidney disease (CKD) and normal kidney function (nonuraemic calciphylaxis; NUC). There are few large series of NUC in the literature. AIM: To compare the clinicopathological features of UC and NUC. METHODS: We retrospectively compared the clinicopathological features of 35 patients with NUC during the period 2010-2020 with those of 53 patients with UC (control group). Cases were classified as NUC in the absence of all of the following: ESKD, significant CKD (defined as serum creatinine > 3 mg/dL or creatinine clearance < 15 mL/min) and acute kidney injury requiring kidney replacement therapy or kidney transplantation. RESULTS: NUC represented 40% of the total cases, and there was a higher number of women (P < 0.01) and a higher median body mass index (P = 0.06) compared with the control UC group. Elevated parathyroid hormone was present in 44% of patients with NUC. Most of the tested patients were positive for lupus anticoagulants (56%). NUC biopsies showed a higher rate of extravascular calcium deposits (73% vs. 47%, P = 0.03). Dermal reactive vascular proliferation was the most common dermal change (32%). CONCLUSIONS: NUC is more common than previously reported and shows a higher predilection for obese postmenopausal women. Undiagnosed hyperparathyroidism shows a possible association with NUC. Lupus anticoagulants were positive in most patients. NUC biopsies are more likely than UC biopsies to display extravascular calcium deposition.


Assuntos
Calciofilaxia , Falência Renal Crônica , Insuficiência Renal Crônica , Calciofilaxia/diagnóstico , Feminino , Humanos , Falência Renal Crônica/complicações , Falência Renal Crônica/terapia , Insuficiência Renal Crônica/complicações , Estudos Retrospectivos , Fatores de Risco
7.
PLoS One ; 16(11): e0259289, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34735516

RESUMO

Arsenic (As) contamination is a serious threat to agriculture and human health worldwide. It can adversely affect the growth attributes of food crops. On the other hand, using thiourea (TU) to ameliorate As stress is an economically consistent approach. However, there is a knowledge gap regarding the combined use of TU and Sewage sludge (SS). SS is considered important, unutilized biomass. It can be used as a fertilizer that has high organic matter and nutrients. Therefore, the current study was performed to evaluate TU and SS sole and combined responses under As toxicity on two wheat genotypes (Markaz 19 and Ujala 16). There were four treatments control (As 50 mg kg-1), SS (30 g kg-1)+TU (6.5 mM)+As, TU+As and SS+As applied with four replications. Results revealed that SS+TU performed significantly better over SS, TU and control for improvement in root and shoot fresh and dry weight of wheat varieties Markaz 19 and Ujala 16 under As toxicity. A significant decrease in POD, SOD and APX of Markaz 19 and Ujala 16 also validated the effective functioning of SS+TU over control. The maximum increase of 71 and 77% was noted in phosphorus, where SS+TU was applied over control in Markaz 19 and Ujala 16, respectively. In conclusion, SS+TU is a better approach than the sole application of SS and TU under As contamination for improvement in wheat growth attributes. More investigations are recommended at the field level under different As contamination and agro-climatic zones to declare SS+TU an effective amendment to mitigate As toxicity in wheat.


Assuntos
Arsênio/toxicidade , Esgotos/química , Tioureia/farmacologia , Triticum/crescimento & desenvolvimento , Biomassa , Produtos Agrícolas/efeitos dos fármacos , Produtos Agrícolas/crescimento & desenvolvimento , Poluição Ambiental , Fotossíntese , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Triticum/efeitos dos fármacos
8.
Sensors (Basel) ; 21(11)2021 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-34204099

RESUMO

In site-specific management, rapid and accurate identification of crop stress at a large scale is critical. Radiometric ground-based data and satellite imaging with advanced spatial and spectral resolution allow for a deeper understanding of crop stress and the level of stress in a given area. This research aimed to assess the potential of radiometric ground-based data and high-resolution QuickBird satellite imagery to determine the leaf area index (LAI), biomass fresh weight (BFW) and chlorophyll meter (Chlm) of maize across well-irrigated, water stress and salinity stress areas in the Nile Delta of Egypt. Partial least squares regression (PLSR) and multiple linear regression (MLR) were evaluated to estimate the three measured traits based on vegetation spectral indices (vegetation-SRIs) derived from these methods and their combination. Maize field visits were conducted during the summer seasons from 28 to 30 July 2007 to collect ground reference data concurrent with the acquisition of radiometric ground-based measurements and QuickBird satellite imagery. The results showed that the majority of vegetation-SRIs extracted from radiometric ground-based data and high-resolution satellite images were more effective in estimating LAI, BFW, and Chlm. In general, the vegetation-SRIs of radiometric ground-based data showed higher R2 with measured traits compared to the vegetation-SRIs extracted from high-resolution satellite imagery. The coefficient of determination (R2) of the significant relationships between vegetation-SRIs of both methods and three measured traits varied from 0.64 to 0.89. For example, with QuickBird high-resolution satellite images, the relationships of the green normalized difference vegetation index (GNDVI) with LAI and BFW showed the highest R2 of 0.80 and 0.84, respectively. Overall, the ground-based vegetation-SRIs and the satellite-based indices were found to be in good agreement to assess the measured traits of maize. Both the calibration (Cal.) and validation (Val.) models of PLSR and MLR showed the highest performance in predicting the three measured traits based on the combination of vegetation-SRIs from radiometric ground-based data and high-resolution QuickBird satellite imagery. For example, validation (Val.) models of PLSR and MLR showed the highest performance in predicting the measured traits based on the combination of vegetation-SRIs from radiometric ground-based data and high-resolution QuickBird satellite imagery with R2 (0.91) of both methods for LAI, R2 (0.91-0.93) for BFW respectively, and R2 (0.82) of both methods for Chlm. The models of PLSR and MLR showed approximately the same performance in predicting the three measured traits and no clear difference was found between them and their combinations. In conclusion, the results obtained from this study showed that radiometric ground-based measurements and high spectral resolution remote-sensing imagery have the potential to offer necessary crop monitoring information across well-irrigated, water stress and salinity stress in regions suffering lack of freshwater resources.


Assuntos
Imagens de Satélites , Zea mays , Clorofila , Egito , Análise dos Mínimos Quadrados
9.
Environ Monit Assess ; 193(8): 510, 2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34302207

RESUMO

Prediction models were developed to estimate the extent to which aluminium, chromium, copper, iron, manganese, nickel, lead, and zinc were absorbed in the grains, leaves, stems, and roots of Sorghum bicolor cultivated in soil with various amendment rate of sewage sludge (0, 10, 20, 30, 40, and 50 g/kg) under greenhouse conditions. It was found that, aside from lead, all the examined metals occurred in significantly higher content in the roots compared to aerial tissues. Furthermore, the r-values were significantly negative between the bioconcentration factors of all metals, apart from aluminium and lead, and soil pH, whereas they were significantly positive between the bioconcentration factors, apart from lead, and soil organic matter content (OM). The r-values were typically significantly positive between the levels of all eight metals in the investigated tissues and in the soil. Moreover, the content of all the eight metals in the tissues exhibited a significant negative r-value with soil pH but a significant positive r-value with soil OM. The eight metal contents in the tissues given by the prediction models were quite similar to the real values, suggesting that the created models performed well, as shown by t-tests. It was thus concluded that prediction models were a viable option for evaluating how safe it was to grow S. bicolor in soils with sewage sludge content and at the same time for keeping track of possible human health hazards.


Assuntos
Metais Pesados , Poluentes do Solo , Sorghum , Monitoramento Ambiental , Humanos , Metais Pesados/análise , Esgotos/análise , Solo , Poluentes do Solo/análise
10.
PLoS One ; 16(6): e0252229, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34086714

RESUMO

The aim of the present investigation was to determine the concentration of heavy metals in the different organs of Pisum sativum L. (garden pea) grown in contaminated soils in comparison to nonpolluted soils in the South Cairo and Giza provinces, Egypt, and their effect on consumers' health. To collect soil and plant samples from two nonpolluted and two polluted farms, five quadrats, each of 1 m2, were collected per each farm and used for growth measurement and chemical analysis. The daily intake of metals (DIM) and its associated health risks (health risk index (HRI) were also assessed. The investigated heavy metals were cadmium (Cd), arsenic (As), chromium (Cr), copper (Cu), nickel (Ni), iron (Fe), manganese (Mn), zinc (Zn), silver (Ag), cobalt (Co) and vanadium (V). Significant differences in soil heavy metals, except As, between nonpolluted and polluted sites were recorded. Fresh and dry phytomass, photosynthetic pigments, fruit production, and organic and inorganic nutrients were reduced in the polluted sites, where there was a high concentration of heavy metals in the fruit. The bioaccumulation factor for all studied heavy metals exceeded 1 in the polluted sites and only Pb, Cu and Mn exceeded 1 in the nonpolluted sites. Except for Fe, the DIM of the studied heavy metals in both sites did not exceed 1 in either children or adults. However, the HRI of Pb, Cd, Fe, and Mn in the polluted plants and Pb in the nonpolluted ones exceeded 1, indicating significant potential health risks to consumers. The authors recommend not to eat garden peas grown in the polluted sites, and farmers should carefully grow heavy metals non-accumulating food crops or non-edible plants for other purposes such as animal forages.


Assuntos
Metais Pesados/efeitos adversos , Pisum sativum/efeitos dos fármacos , Poluentes do Solo/efeitos adversos , Solo/química , Bioacumulação/efeitos dos fármacos , Produtos Agrícolas/efeitos dos fármacos , Egito , Monitoramento Ambiental/métodos , Poluição Ambiental/efeitos adversos , Frutas/efeitos dos fármacos , Saúde , Humanos , Risco
11.
Artigo em Inglês | MEDLINE | ID: mdl-31549921

RESUMO

The present study aims to develop prediction models for estimating the potential uptake of 10 heavy metals (HMs) (cadmium, Cd; cobalt, Co; chromium, Cr; copper, Cu; iron, Fe; manganese, Mn; molybdenum, Mo; nickel, Ni; lead, Pb; zinc, Zn) by the tissues of Pisum sativum (root, shoot and pod) grown in soil amended with sewage sludge (SS) under greenhouse conditions. Soil organic matter (OM) was estimated by loss-on-ignition at 550 °C for 2 h. The pH was determined by shaking the soil and pure water at a 1:5 ratio. For HM quantifications, 0.5-1.0 g of each soil or plant sample was digested using a tri-acid mixture digestion method. The quantities of selected HMs were estimated by means of inductively coupled plasma optical emission spectrometry. Bio-concentration (BCF) and translocation (TF) factors were <1 for most of the HMs. In addition, simple linear correlations were significantly negative between the BCF of all studied HMs and soil pH, except for Pb, Mn and Ni, whereas significant positive correlations were observed between BCFs and soil OM, except for Mn, Ni and Zn. The accumulation of the 10 HMs in P. sativum tissues was predicted using regression models based on the values of the same HM in the soil as well as its pH and OM. The calculated prediction models performed well for most HMs in P. sativum tissues (except Ni in the pod, Cd in the shoot and Mn in the root). All measured soil factors (HM, pH and OM) consistently contributed to HM concentrations in the three tissues of the studied plants. These models may help to evaluate the safe cultivation of this species in soil amended with SS.


Assuntos
Metais Pesados/análise , Modelos Biológicos , Pisum sativum/crescimento & desenvolvimento , Esgotos/química , Poluentes do Solo/análise , Solo/química , Bioacumulação , Metais Pesados/metabolismo , Pisum sativum/química , Pisum sativum/metabolismo , Valor Preditivo dos Testes , Poluentes do Solo/metabolismo
12.
Microb Pathog ; 140: 103947, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31874230

RESUMO

Recently, microbial exopolysaccharides (EPSs) have offered very large field for medical applications owing to their bioactive characteristics. This study aimed to obtain antitumor EPS and to optimize its production using different optimization approaches. Eighty EPSs-producing bacteria were obtained from mud samples. Isolate BS4 was selected as the most potent antitumor EPS-producer and identified as Bacillus mycoides BS4 using 16S rRNA gene sequence analysis. Cell viability and antitumor activity of produced EPS were investigated using microscopic examination and MTT assay. Interestingly, the produced EPS exhibited low cytotoxicity against normal cell baby hamster kidney (BHK) with IC50 at 254 µgml-1 while it exhibited an inhibitory effect against cancer cells of human hepatocellular carcinoma (HepG2) and Colorectal adenocarcinoma cells (Caco-2) with IC50 of 138 µgml-1 and 159 µgml-1, respectively. The purified EPS was characterized using Fourier transform infrared, gel permeation chromatography and gas chromatography-mass spectroscopy. It showed molecular weight of 1.90 × 104 Da and consists of galactose, mannose, glucose and glucuronic acid. The factors affecting EPS production were optimized using one-factor-at-a time and statistical optimization methods. The Placket-Burman (PB) design results indicated that sugarcane molasses, peptone and shaking conditions were the most significant variables, which were further optimized by Response Surface Methodology (RSM). The optimum conditions for EPS production were 8.0% (w/v) sugarcane molasses, 6 gL‒1 peptone and 300 rpm that produce 8.02gL‒1 of EPS. This indicates the potentiality of Bacillus mycoides BS4 for production of EPS with biomedical applications.


Assuntos
Antineoplásicos/farmacologia , Bacillus/química , Polissacarídeos Bacterianos/farmacologia , Antineoplásicos/química , Antineoplásicos/metabolismo , Bacillus/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Hep G2 , Humanos , Peso Molecular , Polissacarídeos Bacterianos/química , Polissacarídeos Bacterianos/metabolismo
13.
Malays Orthop J ; 12(3): 19-23, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30555642

RESUMO

Introduction: Restoration of a functional hand is the ultimate goal following a distal radius tumour resection. The early outcomes of mobile wrist reconstruction are satisfactory; however, long-term results are unpredictable due to late wrist instability and degenerative arthritis. Our aim is to compare mobile wrist reconstruction with wrist fusion (pan-carpal fusion) in our cohort of patients. Materials and Methods: A retrospective cohort study was performed for functional outcomes of all patients who underwent resection for distal radius tumour and treated with either fusion or reconstruction of the wrist in a single institution from years 2000-2013 with a minimum of three years follow-up. Results: Eleven patients were included in the study, six of whom had wrist reconstruction with proximal fibula graft and the remaining five wrist fusion, with a mean follow-up of 6.3 years. The mean Musculoskeletal Tumour Society (MSTS) score was 82.78%, ranging from 70% to 93.3%. Average grip strength compared to the normal contralateral hand was 60.0% for total wrist fusion, which was better than wrist reconstruction with 58.07%. There was no difference in the functional outcome between fusion and mobile reconstruction in our study. Osteoarthritis changes and subluxation of the wrist joint were the most common findings in the long-term follow-up for this group. Conclusion: There was no difference in the functional outcome of the long-term follow-up between the two groups.

14.
Braz. j. microbiol ; 49(3): 452-462, July-Sept. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-951792

RESUMO

Abstract Exopolysaccharide (EPS) biopolymers produced by microorganisms play a crucial role in the environment such as health and bio-nanotechnology sectors, gelling agents in food and cosmetic industries in addition to bio-flocculants in the environmental sector as they are degradable, nontoxic. This study focuses on the improvement of EPS production through manipulation of different culture and environmental conditions using response surface methodology (RSM). Plackett-Burman design indicated that; molasses, yeast extract and incubation temperature are the most effective parameters. Box-Behnken RSM indicated that; the optimum concentration for each parameter was 12% (w/v) for molasses, 6 g/L yeast extract and 30 °C for incubation temperature. The most potent bacterial isolate was identified as Bacillus velezensis KY498625. After production, EPS was extracted, purified using DEAE-cellulose, identified using Fourier transform infrared (FTIR), gel permeation chromatography (GPC) and gas chromatography-mass spectroscopy (GC-MS). The result indicated that; it has molecular weight 1.14 × 105 D consisting of glucose, mannose and galactose.


Assuntos
Polissacarídeos Bacterianos/metabolismo , Bacillus/metabolismo , Polissacarídeos Bacterianos/isolamento & purificação , Polissacarídeos Bacterianos/química , Bacillus/química , Microbiologia Industrial , Espectroscopia de Infravermelho com Transformada de Fourier , Meios de Cultura/metabolismo , Meios de Cultura/química , Peso Molecular
15.
J Microbiol Biotechnol ; 28(6): 917-930, 2018 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-29847861

RESUMO

Intracellular synthesis of silver/silver chloride nanoparticles (Ag/AgCl-NPs) using Meyerozyma guilliermondii KX008616 is reported under aerobic and anaerobic conditions for the first time. The biogenic synthesis of Ag-NP types has been proposed as an easy and cost-effective alternative for various biomedical applications. The interaction of nanoparticles with ethanol production was mentioned. The purified biogenic Ag/AgCl-nanoparticles were characterized by different spectroscopic and microscopic approaches. The purified nanoparticles exhibited a surface plasmon resonance band at 419 and 415 nm, confirming the formation of Ag/AgCl-NPs under aerobic and anaerobic conditions, respectively. The planes of the cubic crystalline phase of the Ag/AgCl-NPs were confirmed by X-ray diffraction. Fourier-transform infrared spectra showed the interactions between the yeast cell constituents and silver ions to form the biogenic Ag/AgCl-NPs. The intracellular Ag/AgCl-NPs synthesized under aerobic condition were homogenous and spherical in shape, with an approximate particle size of 2.5-30nm as denoted by the transmission electron microscopy (TEM). The reaction mixture was optimized by varying reaction parameters, including temperature and pH. Analysis of ultrathin sections of yeast cells by TEM indicated that the biogenic nanoparticles were formed as clusters, known as nanoaggregates, in the cytoplasm or in the inner and outer regions of the cell wall. The study recommends using the biomass of yeast that is used in industrial or fermentation purposes to produce Ag/AgCl-NPs as associated by-products to maximize benefit and to reduce the production cost.


Assuntos
Nanopartículas Metálicas , Saccharomycetales/metabolismo , Compostos de Prata/metabolismo , Prata/metabolismo , Aerobiose , Anaerobiose , Microscopia , Saccharomycetales/crescimento & desenvolvimento , Análise Espectral , Ressonância de Plasmônio de Superfície , Difração de Raios X
16.
Braz J Microbiol ; 49(3): 452-462, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29449173

RESUMO

Exopolysaccharide (EPS) biopolymers produced by microorganisms play a crucial role in the environment such as health and bio-nanotechnology sectors, gelling agents in food and cosmetic industries in addition to bio-flocculants in the environmental sector as they are degradable, nontoxic. This study focuses on the improvement of EPS production through manipulation of different culture and environmental conditions using response surface methodology (RSM). Plackett-Burman design indicated that; molasses, yeast extract and incubation temperature are the most effective parameters. Box-Behnken RSM indicated that; the optimum concentration for each parameter was 12% (w/v) for molasses, 6g/L yeast extract and 30°C for incubation temperature. The most potent bacterial isolate was identified as Bacillus velezensis KY498625. After production, EPS was extracted, purified using DEAE-cellulose, identified using Fourier transform infrared (FTIR), gel permeation chromatography (GPC) and gas chromatography-mass spectroscopy (GC-MS). The result indicated that; it has molecular weight 1.14×105D consisting of glucose, mannose and galactose.


Assuntos
Bacillus/metabolismo , Polissacarídeos Bacterianos/metabolismo , Bacillus/química , Meios de Cultura/química , Meios de Cultura/metabolismo , Microbiologia Industrial , Peso Molecular , Polissacarídeos Bacterianos/química , Polissacarídeos Bacterianos/isolamento & purificação , Espectroscopia de Infravermelho com Transformada de Fourier
17.
BJOG ; 125(7): 820-827, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29052334

RESUMO

OBJECTIVE: To analyse the prevalence and intensity of smoking among pregnant women and their partners, and factors associated with quitting smoking among pregnant women. DESIGN: A prospective cohort study, starting in 2013. SETTING: Andalusia, the south of Spain. SAMPLE: A cohort of 486 healthy pregnant women followed-up on three occasions during pregnancy. METHODS: Estimation of the proportions of women and partners who quit smoking at each trimester. MAIN OUTCOME MEASURES: To determine factors associated in a multivariable model, considering sociodemographic, obstetric, anthropometric, lifestyle variables, and the smoking habits of their partners. RESULTS: A high proportion of women quit smoking during pregnancy (61.08%; 95% confidence interval, 95% CI 53.61-68.55%). The smoking rate amongst mothers decreased from 36.06% (n = 167) before pregnancy to 14.08% (n = 65), 12.39% (n = 54), and 11.92% (n = 51) during the three pregnancy trimesters (P < 0.001), and consumption decreased from 8.71 cigarettes/day in the first trimester to 5.51 cigarettes/day in the second trimester (P < 0.001) and 5.96 cigarettes/day in third trimester (P = 0.0002 first versus third trimester). There was only a minimal decrease in the frequency of smoking among the partners, however: 38.44% (n = 178) before pregnancy, and 36.07% (n = 167), 32.72% (n = 143), and 31.85% (n = 136) during the three trimesters of pregnancy. The consumption of cigarettes did not decrease among partners: 11.75, 11.67, and 12.09 cigarettes/day (P = 0.4299 first versus second trimester; P = 0.654 first versus third trimester). Women whose partner smoked were less likely to quit (adjusted odds ratio, aOR 0.26; 95% CI 0.12-0.55). CONCLUSIONS: About one in ten pregnant women smoked and one in four was a passive smoker. Strategies to reduce tobacco exposure in pregnancy should include a focus on partner smoking. TWEETABLE ABSTRACT: Pregnant women quit smoking cigarettes in pregnancy. What about their partners?


Assuntos
Complicações na Gravidez/psicologia , Gestantes/psicologia , Parceiros Sexuais/psicologia , Abandono do Hábito de Fumar/psicologia , Fumar/psicologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Razão de Chances , Gravidez , Estudos Prospectivos , Abandono do Hábito de Fumar/estatística & dados numéricos , Espanha , Adulto Jovem
19.
Arch Virol ; 162(7): 1985-1994, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28343263

RESUMO

Newcastle disease viruses (NDV) represent a major threat to poultry production worldwide. Recently in Egypt NDV circulated extensively, even in vaccinated farms. In the present study samples were collected from sixteen vaccinated broiler farms in animals exhibiting the typical gross lesions of NDV. Virus isolation and pathogenicity studies for positive samples were carried out in accordance to reference procedures and phylogenetic analysis was carried out based on partial sequences of the Fusion gene. Furthermore, in vivo investigation of the ability of heterologous antibody, induced by commercially available lentogenic strain-based vaccines, to efficiently reduce viral shedding was examined. Results revealed that all the sixteen farms were positive for the presence of NDV. Out of these fifteen were confirmed to due to velogenic viruses, based on a main death time (MDT) ≤ 48 hours and partial sequencing of the F gene that showed the presence of a polybasic amino acid motif. However, three patterns in the cleavage site of these velogenic viruses were identified in the present study. Phylogenetic analysis revealed that all fifteen isolates were clustered with class II genotype VIIb while the remaining isolate (B81) was class II genotype II. Results of the in vivo study revealed that adequate heterologous antibody levels, induced by the proposed vaccination program, sufficiently protected birds from morbidity and mortality. However, virus shedding was quantitatively affected in relation to the time of challenge after vaccination. Altogether, with an absence of vaccines able to induce homologous antibody to the presently circulating viruses, higher antibody levels, which depend on efficient and timely implementation of the vaccination program, are considered as highly important in relation to the reduction of virus shedding.


Assuntos
Doença de Newcastle/virologia , Vírus da Doença de Newcastle/genética , Animais , Anticorpos Antivirais/imunologia , Especificidade de Anticorpos , Galinhas , Egito/epidemiologia , Doença de Newcastle/epidemiologia , Filogenia , Reação em Cadeia da Polimerase Via Transcriptase Reversa
20.
J Appl Microbiol ; 117(5): 1336-47, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25123413

RESUMO

AIM: To evaluate the effect of temperature, pH and SO2 on growth and glycerol production improvement by Saccharomyces cerevisiae mc2, Kloeckera apiculata mF and Oenococcus oeni X2L using the response surface method (RSM). METHODS AND RESULTS: Multifactorial design of cultures with physicochemical factors variations was performed. The micro-organisms grew in all cultures conditions. Overall, after 6 days yeasts prevailed, especially S. cerevisiae (10(9) CFU ml(-1)), while O. oeni reached 10(7) CFU ml(-1). At initial fixed pH 5·5, metabolic behaviour of cultures showed a temperature-dependent response. Total malate consumption occurred at 26°C, 50 mg l(-1) SO2. Glucose and pentoses utilization was highly modified when varying SO2. Ethanol showed negative interaction with temperature-SO2 relationship. At low SO2, glycerol and acetate production increased when temperature enhanced. Predictive results of RSM indicate that 26°C, 60·24 mg l(-1) SO2 and pH 5·5 were the optimal conditions for glycerol and organic acids synthesis compatible with wine quality. CONCLUSIONS: We propose a predictive condition to improve the performance of mixed cultures for must fermentations. SIGNIFICANCE AND IMPACT OF THE STUDY: To optimize the culture conditions to design mixed starters containing autochthonous yeasts and O. oeni strains for winemaking and to obtain products with high glycerol content, low acidity and maintenance of regional characteristics.


Assuntos
Glicerol/metabolismo , Vinho/microbiologia , Interpretação Estatística de Dados , Fermentação , Concentração de Íons de Hidrogênio , Kloeckera/crescimento & desenvolvimento , Kloeckera/metabolismo , Oenococcus/crescimento & desenvolvimento , Oenococcus/metabolismo , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/metabolismo , Dióxido de Enxofre , Temperatura
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