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1.
J Environ Sci (China) ; 148: 38-45, 2025 Feb.
Article de Anglais | MEDLINE | ID: mdl-39095173

RÉSUMÉ

Nitrate (NO3-) is a widespread pollutant in high-salt wastewater and causes serious harm to human health. Although electrochemical removal of nitrate has been demonstrated to be a promising treatment method, the development of low-cost electro-catalysts is still challenging. In this work, a phosphate modified iron (P-Fe) cathode was prepared for electrochemical removal of nitrate in high-salt wastewater. The phosphate modification greatly improved the activity of iron, and the removal rate of nitrate on P-Fe was three times higher than that on Fe electrode. Further experiments and density functional theory (DFT) calculations demonstrated that the modification of phosphoric acid improved the stability and the activity of the zero-valent iron electrode effectively for NO3- removal. The nitrate was firstly electrochemically reduced to ammonium, and then reacted with the anodic generated hypochlorite to N2. In this study, a strategy was developed to improve the activity and stability of metal electrode for NO3- removal, which opened up a new field for the efficient reduction of NO3- removal by metal electrode materials.


Sujet(s)
Électrodes , Fer , Nitrates , Phosphates , Élimination des déchets liquides , Eaux usées , Polluants chimiques de l'eau , Eaux usées/composition chimique , Nitrates/composition chimique , Fer/composition chimique , Phosphates/composition chimique , Polluants chimiques de l'eau/composition chimique , Élimination des déchets liquides/méthodes , Techniques électrochimiques/méthodes
2.
Curr Genet ; 70(1): 12, 2024 Aug 02.
Article de Anglais | MEDLINE | ID: mdl-39093429

RÉSUMÉ

Insoluble phosphorous compounds solubilization by soil bacteria is of great relevance since it puts available the phosphorus to be used by plants. The production of organic acids is the main microbiological mechanism by which insoluble inorganic phosphorus compounds are solubilized. In Gram negative bacteria, gluconic acid is synthesized by the activity of the holoenzyme glucose dehydrogenase-pyrroloquinoline quinine named GDH-PQQ. The use of marker genes is a very useful tool to evaluate the persistence of the introduced bacteria and allow to follow-up the effect of biotic and abiotic factors on these beneficial microorganisms in the soil. In previous studies we detected the presence of the pqqE gene in a great percentage of both non-culturable and culturable native soil bacteria. The objective of this study was to analyze the phylogeny of the sequence of pqqE gene and its potential for the study of phosphate solubilizing bacteria from pure and mixed bacterial cultures and rhizospheric soil samples. For this, the presence of the pqqE gene in the genome of phosphate solubilizing bacteria that belong to several bacteria was determined by PCR. Also, this gene was analyzed from mixed bacterial cultures and rhizospheric soil associated to peanut plants inoculated or not with phosphate solubilizing bacteria. For this, degenerate primers designed from several bacterial genera and specific primers for the genus Pseudomonas spp., designed in this study, were used. DNA template used from simple or mixed bacterial cultures and from rhizospheric soil samples was obtained using two different DNA extraction techniques. Results indicated that pqqE gene amplification product was found in the genome of all Gram negative phosphate solubilizing bacteria analyzed. It was possible to detect this gene in the DNA obtained from mixed cultures where these bacteria grew in interaction with other microorganisms and in that obtained from rhizospheric soil samples inoculated or not with these bacteria. The phylogenetic analysis indicated that pqqE gene is a conserved gene within related genera. In conclusion, pqqE gene could be a potential marker for the study of phosphate solubilizing bacterial populations.


Sujet(s)
Phosphates , Phylogenèse , Microbiologie du sol , Phosphates/métabolisme , Bactéries à Gram négatif/génétique , Bactéries à Gram négatif/isolement et purification , Bactéries à Gram négatif/classification , Solubilité , Marqueurs génétiques , Rhizosphère , Plantes/microbiologie
3.
J Clin Pediatr Dent ; 48(4): 160-167, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-39087226

RÉSUMÉ

Glass ionomer cements (GICs) are the common materials employed in pediatric dentistry because of their specific applications in class I restorations and atraumatic restoration treatments (ART) of deciduous teeth in populations at high risk of caries. Studies show a limited clinical durability of these materials. Attempts have thus been made to incorporate nanoparticles (NPs) into the glass ionomer for improving resistance and make it like the tooth structure. An in vitro experimental study was conducted using the required samples dimensions and prepared based on the test being carried out on the three groups with or without the modification of light-cured glass ionomer. Samples were grouped as follows: control group (G1_C), 2% silver phosphate/hydroxyapatite NPs group (G2_SPH), and 2% titanium dioxide NPs group (G3_TiO2). The physical tests regarding flexural strength (n = 10 per group), solubility (n = 10 per group), and radiopacity (n = 3 per group) were performed. The data were analyzed by Shapiro Wilks test, and one-way analysis of variance (one-way ANOVA), and multiple comparisons by post hoc Tukey's test. The p-value of < 0.05 was considered significant. No statistically significant difference was observed between the control group (G1_C) and (G2_SPH) (p = 0.704) in the flexural strength test, however differences were found between G2_SPH and G3_TiO2 groups, ANOVA (p = 0.006); post hoc Tukey's test (p = 0.014). Pertaining to the solubility, G2_SPH obtained the lowest among the three groups, ANOVA (p = 0.010); post hoc Tukey's test (p = 0.009). The three study groups obtained an adequate radiopacity of >1 mm Al, respectively. The resin-modified glass ionomer cement (RMGIC) was further modified with 2% silver phosphate/hydroxyapatite NPs to improve the physical properties such as enhancing the solubility and sorption without compromising the flexural strength and radiopacity behavior of modified RMGIC. The incorporation of 2% titanium dioxide NPs did not improve the properties studied.


Sujet(s)
Durapatite , Ciment ionomère au verre , Nanoparticules , Phosphates , Titane , Titane/composition chimique , Ciment ionomère au verre/composition chimique , Durapatite/composition chimique , Nanoparticules/composition chimique , Phosphates/composition chimique , Techniques in vitro , Test de matériaux , Humains , Composés de l'argent/composition chimique , Solubilité , Résistance à la flexion
4.
BMC Oral Health ; 24(1): 775, 2024 Jul 10.
Article de Anglais | MEDLINE | ID: mdl-38987748

RÉSUMÉ

Acrylic resins are widely used as the main components in removable orthodontic appliances. However, poor oral hygiene and maintenance of orthodontic appliances provide a suitable environment for the growth of pathogenic microorganisms. In this study, strontium-modified phosphate-based glass (Sr-PBG) was added to orthodontic acrylic resin at 0% (control), 3.75%, 7.5%, and 15% by weight to evaluate the surface and physicochemical properties of the novel material and its in vitro antifungal effect against Candida albicans (C. albicans). Surface microhardness and contact angle did not vary between the control and 3.75% Sr-PBG groups (p > 0.05), and the flexural strength was lower in the experimental groups than in the control group (p < 0.05), but no difference was found with Sr-PBG content (p > 0.05). All experimental groups showed an antifungal effect at 24 and 48 h compared to that in the control group (p < 0.05). This study demonstrated that 3.75% Sr-PBG exhibits antifungal effects against C. albicans along with suitable physicochemical properties, which may help to minimize the risk of adverse effects associated with harmful microbial living on removable orthodontic appliances and promote the use of various materials.


Sujet(s)
Résines acryliques , Antifongiques , Candida albicans , Verre , Test de matériaux , Phosphates , Strontium , Propriétés de surface , Candida albicans/effets des médicaments et des substances chimiques , Résines acryliques/composition chimique , Strontium/pharmacologie , Strontium/composition chimique , Antifongiques/pharmacologie , Verre/composition chimique , Phosphates/pharmacologie , Polymérisation , Dureté , Résistance à la flexion , Humains , Techniques in vitro
5.
Int J Chron Obstruct Pulmon Dis ; 19: 1681-1693, 2024.
Article de Anglais | MEDLINE | ID: mdl-39055391

RÉSUMÉ

Purpose: COPD patients frequently have abnormal serum phosphorus levels. The objective of this study was to examine the correlation between serum phosphorus levels with hospital and 90-day mortality in critically ill patients with COPD. Patients and Methods: The MIMIC IV database was used for this retrospective cohort analysis. We extracted demographics, vital signs, laboratory tests, comorbidity, antibiotic usage, ventilation and scoring systems within the first 24 hours of ICU admission. Restricted cubic splines and multivariate cox regression analysis models were used to evaluate the connection between serum phosphorus with hospital and 90-day mortality. We assessed and classified various factors including gender, age, renal disease, severe liver disease, the utilization of antibiotics and congestive heart failure. Results: We included a total of 3611 patients with COPD, with a median age of 70.7 years. After adjusting for all other factors, we observed a significant positive association between serum phosphate levels with both hospital mortality (HR 1.19, 95% CI: 1.07-1.31, p<0.001) and 90-day mortality (HR 1.15, 95% CI: 1.06-1.24, p<0.001). Compared to the medium group (Q2 ≥3.15, <4.0), the adjusted hazard ratios for hospital mortality were 1.47 (95% CI: 1.08-2, p=0.013), and 1.31 (95% CI: 1.06-1.61, p=0.013) for 90-day mortality in the high group (Q3≥4.0). Hospital mortality decreased at serum phosphate levels below 3.8 mg/dl (HR 0.664, 95% CI: 0.468-0.943, p=0.022), but increased for both hospital (HR 1.312, 95% CI: 1.141-1.509, p<0.001) and 90-day mortality (HR 1.236, 95% CI: 1.102-1.386, p<0.001) when levels were above 3.8 mg/dl. Subgroup and sensitivity analyses yielded consistent results. Conclusion: In critical ill COPD patients, this study demonstrated a non-linear association between serum phosphate levels and both hospital and 90-day mortality. Notably, there was an inflection point at 3.8 mg/dl, indicating a significant shift in outcomes. Future prospective research is necessary to validate this correlation.


Sujet(s)
Marqueurs biologiques , Maladie grave , Mortalité hospitalière , Phosphates , Broncho-pneumopathie chronique obstructive , Humains , Études rétrospectives , Mâle , Femelle , Sujet âgé , Maladie grave/mortalité , Broncho-pneumopathie chronique obstructive/mortalité , Broncho-pneumopathie chronique obstructive/sang , Broncho-pneumopathie chronique obstructive/diagnostic , Adulte d'âge moyen , Facteurs temps , Facteurs de risque , Marqueurs biologiques/sang , Phosphates/sang , Appréciation des risques , Bases de données factuelles , Pronostic , Sujet âgé de 80 ans ou plus , Hyperphosphatémie/sang , Hyperphosphatémie/mortalité , Hyperphosphatémie/diagnostic
6.
Sci Rep ; 14(1): 16997, 2024 Jul 23.
Article de Anglais | MEDLINE | ID: mdl-39043847

RÉSUMÉ

Vitamin D3 is clinically used for the treatment of vitamin D3 deficiency or osteoporosis, partially because of its role in regulating phosphate (Pi) and calcium (Ca2+) homeostasis. The renal sodium-phosphate cotransporter 2a (Npt2a) plays an important role in Pi homeostasis; however, the role of vitamin D3 in hypophosphatemia has never been investigated. We administered vehicle or vitamin D3 to wild-type (WT) mice or hypophosphatemic Npt2a-/- mice. In contrast to WT mice, vitamin D3 treatment increased plasma Pi levels in Npt2a-/- mice, despite similar levels of reduced parathyroid hormone and increased fibroblast growth factor 23. Plasma Ca2+ was increased ~ twofold in both genotypes. Whereas WT mice were able to increase urinary Pi and Ca2+/creatinine ratios, in Npt2a-/- mice, Pi/creatinine was unchanged and Ca2+/creatinine drastically decreased, coinciding with the highest kidney Ca2+ content, highest plasma creatinine, and greatest amount of nephrocalcinosis. In Npt2a-/- mice, vitamin D3 treatment completely diminished Npt2c abundance, so that mice resembled Npt2a/c double knockout mice. Abundance of intestinal Npt2b and claudin-3 (tight junctions protein) were reduced in Npt2a-/- only, the latter might facilitate the increase in plasma Pi in Npt2a-/- mice. Npt2a might function as regulator between renal Ca2+ excretion and reabsorption in response to vitamin D3.


Sujet(s)
Calcium , Cholécalciférol , Homéostasie , Souris knockout , Phosphates , Cotransporteurs sodium-phosphate de type IIa , Animaux , Phosphates/métabolisme , Calcium/métabolisme , Homéostasie/effets des médicaments et des substances chimiques , Souris , Cholécalciférol/pharmacologie , Cholécalciférol/métabolisme , Cotransporteurs sodium-phosphate de type IIa/métabolisme , Cotransporteurs sodium-phosphate de type IIa/génétique , Rein/métabolisme , Rein/effets des médicaments et des substances chimiques , Facteur-23 de croissance des fibroblastes , Hormone parathyroïdienne/métabolisme , Mâle , Hypophosphatémie/métabolisme , Hypophosphatémie/génétique , Cotransporteurs sodium-phosphate de type IIb
7.
Endocrinology ; 165(8)2024 Jul 01.
Article de Anglais | MEDLINE | ID: mdl-39024412

RÉSUMÉ

Osteocytes are embedded in lacunae and connected by canaliculi (lacuno-canalicular network, LCN). Bones from mice with X-linked hypophosphatemia (Hyp), which have impaired production of 1,25 dihydroxyvitamin D (1,25D) and hypophosphatemia, have abnormal LCN structure that is improved by treatment with 1,25D or an anti-FGF23 targeting antibody, supporting roles for 1,25D and phosphate in regulating LCN remodeling. Bones from mice lacking the vitamin D receptor (VDR) in osteocytes (Vdrf/f;Dmp1Cre+) and mice lacking the sodium phosphate transporter 2a (Npt2aKO), which have low serum phosphate with high serum 1,25D, have impaired LCN organization, demonstrating that osteocyte-specific actions of 1,25D and hypophosphatemia regulate LCN remodeling. In osteoclasts, nuclear factor of activated T cells cytoplasmic 1 (NFATc1) is critical for stimulating bone resorption. Since osteocytes also resorb matrix, we hypothesize that NFATc1 plays a role in 1,25D and phosphate-mediated LCN remodeling. Consistent with this, 1,25D and phosphate suppress Nfatc1 mRNA expression in IDG-SW3 osteocytes, and knockdown of Nfatc1 expression in IDG-SW3 cells blocks 1,25D- and phosphate-mediated suppression of matrix resorption gene expression and 1,25D- and phosphate-mediated suppression of RANKL-induced acidification of the osteocyte microenvironment. To determine the role of NFATc1 in 1,25D- and phosphate-mediated LCN remodeling in vivo, histomorphometric analyses of tibiae from mice lacking osteocyte-specific Nfatc1 in Vdrf/f;Dmp1Cre+ and Npt2aKO mice were performed, demonstrating that bones from these mice have decreased lacunar size and expression of matrix resorption genes, and improved canalicular structure compared to Vdrf/f;Dmp1Cre+ and Npt2aKO control. This study demonstrates that NFATc1 is necessary for 1,25D- and phosphate-mediated regulation of LCN remodeling.


Sujet(s)
Remodelage osseux , Facteur-23 de croissance des fibroblastes , Facteurs de transcription NFATC , Ostéocytes , Phosphates , Vitamine D , Animaux , Mâle , Souris , Remodelage osseux/effets des médicaments et des substances chimiques , Rachitisme hypophosphatémique familial/métabolisme , Rachitisme hypophosphatémique familial/génétique , Souris de lignée C57BL , Souris knockout , Facteurs de transcription NFATC/métabolisme , Facteurs de transcription NFATC/génétique , Ostéocytes/métabolisme , Ostéocytes/effets des médicaments et des substances chimiques , Phosphates/métabolisme , Récepteur calcitriol/métabolisme , Récepteur calcitriol/génétique , Cotransporteurs sodium-phosphate de type IIa/génétique , Cotransporteurs sodium-phosphate de type IIa/métabolisme , Vitamine D/pharmacologie , Vitamine D/analogues et dérivés , Femelle
8.
Sci Rep ; 14(1): 16737, 2024 Jul 20.
Article de Anglais | MEDLINE | ID: mdl-39033227

RÉSUMÉ

In this comprehensive investigation, we successfully isolated and characterized 40 distinct plant-associated halotolerant bacteria strains obtained from three halophytic plant species: Tamarix nilotica, Suaeda pruinosa, and Arthrocnemum macrostachyum. From this diverse pool of isolates, we meticulously selected five exceptional plant-associated halotolerant bacteria strains through a judiciously designed seed biopriming experiment and then identified molecularly. Bacillus amyloliquefaciens DW6 was isolated from A. macrostachyum. Three bacteria (Providencia rettgeri DW3, Bacillus licheniformis DW4, and Salinicoccus sesuvii DW5) were isolated for the first time from T. nilotica, S. pruinosa and S. pruinosa, respectively. Paenalcaligenes suwonensis DW7 was isolated for the first time from A. macrostachyum. These plant-associated halotolerant bacteria exhibited growth-promoting activities, including phosphate solubilization, nitrogen fixation, and production of bioactive compounds, i.e., ammonia, phytohormones, hydrogen cyanide, siderophores, and exopolysaccharides. A controlled laboratory experiment was conducted to reduce the detrimental impact of soil salinity. Vicia faba seedlings were inoculated individually or in mixtures by the five most effective plant-associated halotolerant bacteria to reduce the impact of salt stress and improve growth parameters. The growth parameters were significantly reduced due to the salinity stress in the control samples, compared to the experimental ones. The unprecedented novelty of our findings is underscored by the demonstrable efficacy of co-inoculation with these five distinct bacterial types as a pioneering bio-approach for countering the deleterious effects of soil salinity on plant growth. This study thus presents a remarkable contribution to the field of plant science and offers a promising avenue for sustainable agriculture in saline environments.


Sujet(s)
Salinité , Vicia faba , Vicia faba/croissance et développement , Vicia faba/microbiologie , Plantes tolérantes au sel/microbiologie , Plantes tolérantes au sel/croissance et développement , Fixation de l'azote , Bactéries/croissance et développement , Bactéries/métabolisme , Bactéries/classification , Tamaricaceae/microbiologie , Tamaricaceae/croissance et développement , Chenopodiaceae/microbiologie , Chenopodiaceae/croissance et développement , Microbiologie du sol , Tolérance au sel , Phosphates/métabolisme
9.
BMC Plant Biol ; 24(1): 696, 2024 Jul 23.
Article de Anglais | MEDLINE | ID: mdl-39044142

RÉSUMÉ

BACKGROUND: Phosphorus (P) deficiency, a major nutrient stress, greatly hinders plant growth. Phosphate (Pi) uptake in plant roots relies on PHT1 family transporters. However, melon (Cucumis melo L.) lacks comprehensive identification and characterization of PHT1 genes, particularly their response patterns under diverse stresses. RESULTS: This study identified and analyzed seven putative CmPHT1 genes on chromosomes 3, 4, 5, 6, and 7 using the melon genome. Phylogenetic analysis revealed shared motifs, domain compositions, and evolutionary relationships among genes with close histories. Exon number varied from 1 to 3. Collinearity analysis suggested segmental and tandem duplications as the primary mechanisms for CmPHT1 gene family expansion. CmPHT1;4 and CmPHT1;5 emerged as a tandemly duplicated pair. Analysis of cis-elements in CmPHT1 promoters identified 14 functional categories, including putative PHR1-binding sites (P1BS) in CmPHT1;4, CmPHT1;6, and CmPHT1;7. We identified that three WRKY transcription factors regulated CmPHT1;5 expression by binding to its W-box element. Notably, CmPHT1 promoters harbored cis-elements responsive to hormones and abiotic factors. Different stresses regulated CmPHT1 expression differently, suggesting that the adjusted expression patterns might contribute to plant adaptation. CONCLUSIONS: This study unveils the characteristics, evolutionary diversity, and stress responsiveness of CmPHT1 genes in melon. These findings lay the foundation for in-depth investigations into their functional mechanisms in Cucurbitaceae crops.


Sujet(s)
Cucumis melo , Régulation de l'expression des gènes végétaux , Phosphates , Phylogenèse , Protéines végétales , Stress physiologique , Cucumis melo/génétique , Cucumis melo/métabolisme , Phosphates/métabolisme , Protéines végétales/génétique , Protéines végétales/métabolisme , Stress physiologique/génétique , Gènes de plante , Protéines de transport du phosphate/génétique , Protéines de transport du phosphate/métabolisme , Transport biologique/génétique
10.
BMC Plant Biol ; 24(1): 642, 2024 Jul 08.
Article de Anglais | MEDLINE | ID: mdl-38972980

RÉSUMÉ

Among the several threats to humanity by anthropogenic activities, contamination of the environment by heavy metals is of great concern. Upon entry into the food chain, these metals cause serious hazards to plants and other organisms including humans. Use of microbes for bioremediation of the soil and stress mitigation in plants are among the preferred strategies to provide an efficient, cost-effective, eco-friendly solution of the problem. The current investigation is an attempt in this direction where fungal strain PH1 was isolated from the rhizosphere of Parthenium hysterophorus which was identified as Aspergillus niger by sequence homology of the ITS 1 and ITS 4 regions of the rRNA. The strain was tested for its effect on growth and biochemical parameters as reflection of its potential to mitigate Pb stress in Zea mays exposed to 100, 200 and 500 µg of Pb/g of soil. In the initial screening, it was revealed that the strain has the ability to tolerate lead stress, solubilize insoluble phosphate and produce plant growth promoting hormones (IAA and SA) and other metabolites like phenolics, flavonoids, sugar, protein and lipids. Under 500 µg of Pb/g of soil, Z. mays exhibited significant growth retardation with a reduction of 31% in root length, 30.5% in shoot length, 57.5% in fresh weight and 45.2% in dry weight as compared to control plants. Inoculation of A. niger to Pb treated plants not only restored root and shoot length, rather promoted it to a level significantly higher than the control plants. Association of the strain modulated the physio-hormonal attributes of maize plants that resulted in their better growth which indicated a state of low stress. Additionally, the strain boosted the antioxidant defence system of the maize there by causing a significant reduction in the ascorbic acid peroxidase (1.5%), catalase (19%) and 1,1-diphenyl-2 picrylhydrazyl (DPPH) radical scavenging activity (33.3%), indicating a lower stress condition as compared to their non-inoculated stressed plants. Based on current evidence, this strain can potentially be used as a biofertilizer for Pb-contaminated sites where it will improve overall plant health with the hope of achieving better biological and agricultural yields.


Sujet(s)
Antioxydants , Aspergillus niger , Plomb , Phosphates , Photosynthèse , Zea mays , Zea mays/croissance et développement , Zea mays/microbiologie , Zea mays/effets des médicaments et des substances chimiques , Zea mays/métabolisme , Aspergillus niger/métabolisme , Plomb/métabolisme , Antioxydants/métabolisme , Photosynthèse/effets des médicaments et des substances chimiques , Phosphates/métabolisme , Polluants du sol/métabolisme , Stress physiologique , Dépollution biologique de l'environnement
12.
Int J Mol Sci ; 25(13)2024 Jun 29.
Article de Anglais | MEDLINE | ID: mdl-39000305

RÉSUMÉ

Nitrosyl iron complexes are remarkably multifactorial pharmacological agents. These compounds have been proven to be particularly effective in treating cardiovascular and oncological diseases. We evaluated and compared the antioxidant activity of tetranitrosyl iron complexes (TNICs) with thiosulfate ligands and dinitrosyl iron complexes (DNICs) with glutathione (DNIC-GS) or phosphate (DNIC-PO4-) ligands in hemoglobin-containing systems. The studied effects included the production of free radical intermediates during hemoglobin (Hb) oxidation by tert-butyl hydroperoxide, oxidative modification of Hb, and antioxidant properties of nitrosyl iron complexes. Measuring luminol chemiluminescence revealed that the antioxidant effect of TNICs was higher compared to DNIC-PO4-. DNIC-GS either did not exhibit antioxidant activity or exerted prooxidant effects at certain concentrations, which might have resulted from thiyl radical formation. TNICs and DNIC-PO4- efficiently protected the Hb heme group from decomposition by organic hydroperoxides. DNIC-GS did not exert any protective effects on the heme group; however, it abolished oxoferrylHb generation. TNICs inhibited the formation of Hb multimeric forms more efficiently than DNICs. Thus, TNICs had more pronounced antioxidant activity than DNICs in Hb-containing systems.


Sujet(s)
Antioxydants , Hémoglobines , Fer , Phosphates , Thiosulfates , Thiosulfates/pharmacologie , Thiosulfates/composition chimique , Hémoglobines/métabolisme , Hémoglobines/composition chimique , Fer/métabolisme , Fer/composition chimique , Phosphates/composition chimique , Phosphates/métabolisme , Ligands , Antioxydants/pharmacologie , Thiols/composition chimique , Thiols/métabolisme , Oxydoréduction/effets des médicaments et des substances chimiques , Oxydes d'azote/composition chimique , Oxydes d'azote/pharmacologie , Oxydes d'azote/métabolisme , Glutathion/métabolisme , Animaux
13.
Environ Sci Pollut Res Int ; 31(32): 45138-45161, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-38961016

RÉSUMÉ

The extraction of phosphorite ore in Tunisia has resulted in the discharge of substantial amounts of phosphatic sludge into the region's water system. To mitigate this environmental issue and prevent heavy metal leaching, a geopolymerization process was employed using two types of Tunisian calcined phosphate sludges (Cal-PS1 and Cal-PS2) as substitutes for alkali-activated metakaolin. This study aimed to investigate and compare the physical and mechanical properties of the resulting geopolymers. The optimal substitution ratio of metakaolin with calcined phosphate sludge was determined to be 1.5, equivalent to 20 wt.% of calcined phosphate sludge. Compressive strength tests conducted after 28 days of curing revealed values of 37 MPa for Cal-PS1 specimens and 28 MPa for Cal-PS2 geopolymers while compressive strength of geopolymers soaked in water for 28 days showed a decrease with the addition of phosphate sludges. The specific surface areas of Cal-PS1 geopolymers ranged from 16.3 to 16.9 m2/g and from 17.62 to 18.73 m2/g for Cal-PS2 specimens exhibiting a mesoporous structure. The elasticity modulus of the geopolymers was found to increase with the increase of the apparent density of geopolymers and with the sludges content but it tended to be lower than the Portland cement elasticity modulus. Leaching test was conducted to evaluate the potential environmental applications of the geopolymers. This test demonstrated effective containment of heavy metals within the geopolymers' network, except for low levels of arsenic.


Sujet(s)
Phosphates , Phosphates/composition chimique , Eaux d'égout/composition chimique , Kaolin/composition chimique , Polymères/composition chimique , Alcalis/composition chimique , Tunisie
14.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(7): 677-682, 2024 Jul 15.
Article de Chinois | MEDLINE | ID: mdl-39014942

RÉSUMÉ

OBJECTIVES: To study the diagnosis, treatment, and complications of hypophosphatemic rickets (HR) in children, explore effectiveness evaluation indicators for the disease, and understand the pattern in height growth among these patients. METHODS: A retrospective analysis of the initial clinical data and five-year follow-up data of 85 children with HR treated at Children's Hospital of Nanjing Medical University from January 2008 to December 2022. RESULTS: Among the 85 children with HR, there were 46 males (54%) and 39 females (46%). The age at initial diagnosis ranged from 6 months to 13 years and 9 months, with a median age of 2.75 years. The average height standard deviation score was -2.0±1.1. At initial diagnosis, children exhibited reduced blood phosphate levels and elevated alkaline phosphatase (ALP), with 99% (84/85) presenting with lower limb deformities. The positive rate for PHEX gene mutations was 93% (55/59). One year post-treatment, there was a significant reduction in ALP levels and the gap between the lower limbs (P<0.05). The fastest height growth occurred in the first year after treatment, at 8.23 cm/year, with a peak height velocity (PHV) phase lasting about two years during puberty. The height increased by 9-20 cm in male children during the PHV stage and 10-15 cm in female children. Major complications included nephrocalcinosis and hyperparathyroidism. The incidence rate of nephrocalcinosis in the first year after treatment was 55% (22/40), which increased with the duration of the disease (P<0.001); an increased urinary phosphate/creatinine ratio was positively associated with a higher risk of nephrocalcinosis (OR=1.740, P<0.001). The incidence of hyperparathyroidism in the first year after treatment was 64% (27/42). CONCLUSIONS: For children presenting with lower limb deformities, short stature, and slow growth, early testing for blood levels of phosphate, calcium, and ALP, along with imaging examinations of the lower limbs, can aid in the early diagnosis of HR. Genetic testing may be utilized for definitive confirmation when necessary. ALP combined with improvements in skeletal deformities and annual height growth can serve as indicators of therapeutic effectiveness for HR. Compared to normal children, children with HR demonstrate a lower height increase during the PHV phase, necessitating close follow-up and timely adjustment of treatment plans Citation:Chinese Journal of Contemporary Pediatrics, 2024, 26(7): 677-682.


Sujet(s)
Rachitisme hypophosphatémique , Humains , Mâle , Femelle , Enfant , Études rétrospectives , Enfant d'âge préscolaire , Nourrisson , Adolescent , Études de suivi , Rachitisme hypophosphatémique/génétique , Rachitisme hypophosphatémique/étiologie , Phosphatase alcaline/sang , Taille , PHEX Phosphate regulating neutral endopeptidase/génétique , Phosphates/sang , Mutation
18.
Microbiol Res ; 286: 127823, 2024 Sep.
Article de Anglais | MEDLINE | ID: mdl-38959523

RÉSUMÉ

Plant-associated streptomycetes play important roles in plant growth and development. However, knowledge of volatile-mediated crosstalk between Streptomyces spp. and plants remains limited. In this study, we investigated the impact of volatiles from nine endophytic Streptomyces strains on the growth and development of plants. One versatile strain, Streptomyces setonii WY228, was found to significantly promote the growth of Arabidopsis thaliana and tomato seedlings, confer salt tolerance, and induce early flowering and increased fruit yield following volatile treatment. Analysis of plant growth-promoting traits revealed that S. setonii WY228 could produce indole-3-acetic acid, siderophores, ACC deaminase, fix nitrogen, and solubilize inorganic phosphate. These capabilities were further confirmed through genome sequencing and analysis. Volatilome analysis indicated that the volatile organic compounds emitted from ISP-2 medium predominantly comprised sesquiterpenes and 2-ethyl-5-methylpyrazine. Further investigations showed that 2-ethyl-5-methylpyrazine and sesquiterpenoid volatiles were the primary regulators promoting growth, as confirmed by experiments using the terpene synthesis inhibitor phosphomycin, pure compounds, and comparisons of volatile components. Transcriptome analysis, combined with mutant and inhibitor studies, demonstrated that WY228 volatiles promoted root growth by activating Arabidopsis auxin signaling and polar transport, and enhanced root hair development through ethylene signaling activation. Additionally, it was confirmed that volatiles can stimulate plant abscisic acid signaling and activate the MYB75 transcription factor, thereby promoting anthocyanin synthesis and enhancing plant salt stress tolerance. Our findings suggest that aerial signaling-mediated plant growth promotion and abiotic stress tolerance represent potentially overlooked mechanisms of Streptomyces-plant interactions. This study also provides an exciting strategy for the regulation of plant growth and the improvement of horticultural crop yields within sustainable agricultural practices.


Sujet(s)
Arabidopsis , Acides indolacétiques , Tolérance au sel , Streptomyces , Composés organiques volatils , Arabidopsis/croissance et développement , Arabidopsis/microbiologie , Streptomyces/métabolisme , Composés organiques volatils/métabolisme , Acides indolacétiques/métabolisme , Facteur de croissance végétal/métabolisme , Développement des plantes/effets des médicaments et des substances chimiques , Stress salin , Transduction du signal , Racines de plante/microbiologie , Racines de plante/croissance et développement , Plant/croissance et développement , Plant/microbiologie , Plant/métabolisme , Régulation de l'expression des gènes végétaux , Carbon-carbon lyases/métabolisme , Phosphates/métabolisme
19.
Microbiol Res ; 286: 127818, 2024 Sep.
Article de Anglais | MEDLINE | ID: mdl-38970906

RÉSUMÉ

The agricultural land in the Indian Himalayan region (IHR) is susceptible to various spells of snowfall, which can cause nutrient leaching, low temperatures, and drought conditions. The current study, therefore, sought an indigenous psychrotrophic plant growth-promoting (PGP) bacterial inoculant with the potential to alleviate crop productivity under cold and drought stress. Psychrotrophic bacteria preisolated from the night-soil compost of the Lahaul Valley of northwestern Himalaya were screened for phosphate (P) and potash (K) solubilization, nitrogen fixation, indole acetic acid (IAA) production, siderophore and HCN production) in addition to their tolerance to drought conditions for consortia development. Furthermore, the effects of the selected consortium on the growth and development of wheat (Triticum aestivum L.) and maize (Zea mays L.) were assessed in pot experiments under cold semiarid conditions (50 % field capacity). Among 57 bacteria with P and K solubilization, nitrogen fixation, IAA production, siderophore and HCN production, Pseudomonas protegens LPH60, Pseudomonas atacamensis LSH24, Psychrobacter faecalis LUR13, Serratia proteamaculans LUR44, Pseudomonas mucidolens LUR70, and Glutamicibacter bergerei LUR77 exhibited tolerance to drought stress (-0.73 MPa). The colonization of wheat and maize seeds with these drought-tolerant PGP strains resulted in a germination index >150, indicating no phytotoxicity under drought stress. Remarkably, a particular strain, Pseudomonas sp. LPH60 demonstrated antagonistic activity against three phytopathogens Ustilago maydis, Fusarium oxysporum, and Fusarium graminearum. Treatment with the consortium significantly increased the foliage (100 % and 160 %) and root (200 % and 133 %) biomasses of the wheat and maize plants, respectively. Furthermore, whole-genome sequence comparisons of LPH60 and LUR13 with closely related strains revealed genes associated with plant nutrient uptake, phytohormone synthesis, siderophore production, hydrogen cyanide (HCN) synthesis, volatile organic compound production, trehalose and glycine betaine transport, cold shock response, superoxide dismutase activity, and gene clusters for nonribosomal peptide synthases and polyketide synthetases. With their PGP qualities, biocontrol activity, and ability to withstand environmental challenges, the developed consortium represents a promising cold- and drought-active PGP bioinoculant for cereal crops grown in cold semiarid regions.


Sujet(s)
Basse température , Produits agricoles , Sécheresses , Acides indolacétiques , Sidérophores , Microbiologie du sol , Triticum , Zea mays , Triticum/microbiologie , Zea mays/microbiologie , Zea mays/croissance et développement , Produits agricoles/microbiologie , Acides indolacétiques/métabolisme , Sidérophores/métabolisme , Fixation de l'azote , Inde , Acide cyanhydrique/métabolisme , Bactéries/génétique , Bactéries/métabolisme , Bactéries/classification , Consortiums microbiens/génétique , Racines de plante/microbiologie , Phosphates/métabolisme , Fusarium/génétique , Stress physiologique , Maladies des plantes/microbiologie , Facteur de croissance végétal/métabolisme , Pseudomonas/génétique , Pseudomonas/métabolisme
20.
Environ Geochem Health ; 46(8): 294, 2024 Jul 08.
Article de Anglais | MEDLINE | ID: mdl-38976147

RÉSUMÉ

Lushan Yunwu tea quality is limited by soil acidity and sterility. This article examined a 3-year localization experiment at 1100 m altitude to demonstrate the sustainable management of conditioners, calcium magnesium phosphate (P), rapeseed cake (C), and combination application (P + C) by one-time application on the soil-tea system in Mount Lushan. The study found that conditioners (P, C, P + C) reduced soil acidification and maintained a pH of 4.75-5.34, ideal for tea tree development for 3 years. Phosphorus activation coefficient (PAC), nitrogen activation coefficient (NAC), and organic matter (OM) content were significantly higher (P < 0.05) in the first year after conditioner treatment, with P + C being the best. After P + C, PAC, NAC, and OM rose by 31.25%, 47.70%, and 10.06 g kg-1 compared to CK. In comparison to the CK, tea's hundred-bud weight (BW), free amino acids (AA), tea polyphenols (TPC), and chlorophyll (Chl) content of P + C treatment got 29.98%, 14.41%, 22.49%, and 28.85% increase compared to that of the CK, respectively. In the second year, the three treatments of P, C and P + C still had significant moderating effects on the physicochemical properties of the soil and the quality indexes of the tea leaves. The PAC of the soil under the three treatments increased by 0.06%, 0.07% and 0.18%, respectively, as compared to the control.P + C increased BW, AA, TPC and Chl of tea for 2 years. Three conditioners had 2-year regulatory impacts on soil fertility indicators, tea output, and quality. C and P + C both increased soil OM by 18.59% and 21.78% compared to CK in the third year, outperforming P treatment. Redundancy analysis revealed that the primary physicochemical factors influencing tea output and quality were soil OM and pH, with available phosphorus, urease, acid phosphatase, and available nitrogen following closely afterwards.


Sujet(s)
Sol , Sol/composition chimique , Chine , Thé/composition chimique , Camellia sinensis/composition chimique , Concentration en ions d'hydrogène , Engrais , Brassica rapa , Phosphates , Azote , Chlorophylle , Phosphore/analyse
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