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1.
Environ Sci Pollut Res Int ; 31(10): 14971-14979, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38285253

RESUMEN

This study was conducted to investigate the efficacy of smoke-water obtained from biotics, for example coconut shells, rice husk, and pine cones on banana ripening, and compared with calcium carbide. Bio-chemical composition and remarkable bactericidal effect towards ATCC cultures of Escherichia coli, Staphylococcus aureus, and Bacillus cereus discovered the biological safety of the smoke-water in all collected smoke-water samples. Further, inductively coupled plasma mass spectrometry (ICP-MS) was carried out to investigate heavy metals; however, no traces were found in all collected samples. Consequently, it is proposed that heavy metal-free smoke-water obtained from various biotics series might be employed as ultrasafe fruit ripening as compared to calcium carbide (CaC2) that was found with heavy metal traces.


Asunto(s)
Acetileno/análogos & derivados , Metales Pesados , Musa , Humo , Análisis Costo-Beneficio , Metales Pesados/análisis
2.
Toxicol Res (Camb) ; 12(5): 711-715, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37915477

RESUMEN

A recent incidence reported in NEWS media of artificial fruits ripening agent's toxic to health and killed several seasonal fruit eaters because of the toxicity of the fruit introduced with such toxic ripening agents that affect adversely on health of humans and animals both consumers equivalently have been highlighted in this study.

3.
Plant J ; 115(5): 1316-1330, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37235700

RESUMEN

Increasing concentration of CO2 has significant impacts on many biological processes in plants, and its impact is closely associated with changes in the ratio of photosynthesis to photorespiration. Studies have reported that high CO2 can promote carbon fixing and alleviate plant oxidative damage in response to environmental stresses. However, the effect of high CO2 on fatty acid (FA) metabolism and cellular redox balance in FA-deficient plants is rarely reported. In this study, we identified a high-CO2 -requiring mutant cac2 through forward genetic screening. CAC2 encodes biotin carboxylase, which is one of the subunits of plastid acetyl-CoA carboxylase and participates in de novo FA biosynthesis. Null mutation of CAC2 is embryonic lethal. A point mutation of CAC2 in cac2 mutants produces severe defects in chloroplast development, plant growth and photosynthetic performance. These morphological and physiological defects were largely absent under high CO2 conditions. Metabolite analyses showed that FA contents in cac2-1 leaves were decreased, while photorespiratory metabolites, such as glycine and glycolate, did not significantly change. Meanwhile, cac2 exhibited higher reactive oxygen species (ROS) levels and mRNA expression of stress-responsive genes than the wild-type, indicating that cac2 plants may suffer oxidative stress under ambient CO2 conditions. Elevated CO2 significantly increased FA contents, especially C18:3-FA, and reduced ROS accumulation in cac2-1 leaves. We propose that stress mitigation by high CO2 in cac2 could be due to increased FA levels by promoting carbon assimilation, and the prevention of over-reduction due to decreased photorespiration.


Asunto(s)
Arabidopsis , Arabidopsis/metabolismo , Dióxido de Carbono/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Oxidación-Reducción , Fotosíntesis/fisiología , Estrés Oxidativo , Hojas de la Planta/metabolismo , Plantas/metabolismo , Carbono/metabolismo , Ácidos Grasos/metabolismo
4.
Small ; 19(11): e2205533, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36581562

RESUMEN

The 2D graphyne-related scaffolds linked by carbon-carbon triple bonds have demonstrated promising applications in the field of catalysis and energy storage due to their unique features including high conductivity, permanent porosity, and electron-rich properties. However, the construction of related scaffolds is still mainly limited to the cross-linking of CaC2 with multiple substituted aromatic halogens and there is still a lack of efficient methodology capable of introducing high-concentration heteroatoms within the architectures. The development of alternative and facile synthesis procedures to afford nitrogen-abundant graphyne materials is highly desirable yet challenging in the field of energy storage, particularly via the facile mechanochemical procedure under neat and ambient conditions. Herein, graphyne materials with abundant nitrogen-containing species (nitrogen content of 6.9-29.3 wt.%), tunable surface areas (43-865 m2  g-1 ), and hierarchical porosity are produced via the mechanochemistry-driven pathway by deploying highly electron-deficient multiple substituted aromatic nitriles as the precursors, which can undergo cross-linking reaction with CaC2 to afford the desired nitrogen-doped graphyne scaffolds efficiently. Unique structural features of the as-synthesized materials contributed to promising performance in supercapacitor-related applications, delivering high capacitance of 254.5 F g-1 at 5 mV s-1 , attractive rate performance, and good long-term stability.

5.
Materials (Basel) ; 15(15)2022 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-35897543

RESUMEN

In order to realize the high-value utilization of copper slag, a process for preparing Cu-Fe alloy through the reduction of copper slag is proposed. The sulfur in the alloy exists in the form of matte inclusions, which is different from sulfur in molten iron. The reaction of CaO with Cu2S is difficult. It is necessary to add a reducing agent to promote desulfurization. To avoid the introduction of other elements, Fe-Mn and CaC2 additions were used as desulfurizers for the desulfurization of Cu-Fe alloy. The thermodynamics of the desulfurization reaction were calculated and the experimental process was studied. It was found that the Gibbs free energy of desulfurization reactions was negative for Fe-Mn and that CaC2 can reduce the sulfur in the alloy to 0.0013% and 0.0079%, respectively. The desulfurization process affected the shape of copper in the alloy. Part of copper in this alloy exists in the form of nano-copper spheres, and the size of the spheres is found to increase after desulfurization. Reducing agents can facilitate the desulfurization process of stable sulfides.

6.
Cell Calcium ; 103: 102554, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35193095

RESUMEN

Androgen deprivation therapy (ADT) is the main treatment for advanced prostate cancer (PCa) but resistance results in progression to terminal castrate resistant PCa (CRPC), where there is an unmet therapeutic need. Aberrant intracellular calcium (Cai2+) is known to promote neoplastic transformation and treatment resistance. There is growing evidence that voltage gated calcium channel (VGCC) expression is increased in cancer, particularly CACNA1D/CaV1.3 in CRPC. The aim of this study was to investigate if increased CaV1.3 drives resistance to ADT and determine its associated impact on Cai2+ and cancer biology. Bioinformatic analysis revealed that CACNA1D gene expression is increased in ADT treated PCa patients. This was corroborated in both in vivo LNCaP xenograft mouse and in vitro PCa cell line models, which demonstrated a significant increase in CaV1.3 protein expression following ADT with bicalutamide. Expression was found to be of a shortened 170kDa CaV1.3 isoform associated with plasma and intracellular membranes, which failed to induce calcium influx following membrane depolarisation. Instead, under ADT CaV1.3 mediated a rise in basal cytosolic calcium and an increase in store operated calcium entry (SOCE). This mechanism was found to promote the proliferation and survival of ADT resistant CRPC cells. Overall, this study demonstrates for the first time in PCa that under ADT specific CaV1.3 isoforms promote an upregulation of SOCE which contributes to treatment resistance and CRPC biology. Thus, this novel oncochannel represents a target for therapeutic development to improve PCa patient outcomes.


Asunto(s)
Neoplasias de la Próstata Resistentes a la Castración , Neoplasias de la Próstata , Antagonistas de Andrógenos/farmacología , Antagonistas de Andrógenos/uso terapéutico , Andrógenos/farmacología , Andrógenos/uso terapéutico , Animales , Calcio/metabolismo , Línea Celular Tumoral , Humanos , Masculino , Ratones , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Neoplasias de la Próstata Resistentes a la Castración/genética , Neoplasias de la Próstata Resistentes a la Castración/metabolismo , Regulación hacia Arriba
7.
J Hazard Mater ; 416: 125783, 2021 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-33839503

RESUMEN

In order to investigate the explosion process of calcium carbide (CaC2) dust in the acetylene (C2H2) atmosphere, the explosion characteristics of C2H2 gas and C2H2/CaC2 dust gas-solid two-phase mixture were studied using a 20-L spherical vessel, and the chemical composition of solid residues after explosion were also analyzed. Experimental results showed that the Pex values of C2H2 gas explosion rose first and then remained stable with the increasing stoichiometric ratio values (φ) of C2H2/air, while the (dP/dt)ex values tended to increase at early stage and then decrease, the inflection point of (dP/dt)ex values was φ = 1.78. The explosion severity and risk of C2H2 gas were enhanced by adding CaC2 dust, and the optimum additive concentration of CaC2 dust was 100 g/m3. In the oxygen atmosphere, the C2H2/CaC2 hybrid explosion was divided into two stages when the concentration of CaC2 dust was over 300 g/m3. The explosion risk of the first stage (Stage Ⅰ) was much more serious, while the explosion severity of the second stage (Stage Ⅱ) was much more fierce. The solid residues of hybrid explosion only contained CaO in the oxygen atmosphere, however, Ca(OH)2 and CaO were detected in the solid residues in the air atmosphere, owing to the combustion heat of C2H2 gas in oxygen was higher than that in air. The hydrolysis reaction time of CaC2 particle with large particle size was prolonged, and the diffusion of solid product layer and surface chemical reaction both influenced the hydrolysis process according to the shrinking core model. Based on the explosion and chemical analysis experiments, the explosion mechanism of C2H2/CaC2 dust gas-solid two-phase mixture was analyzed systematically.

8.
ACS Appl Mater Interfaces ; 12(29): 33076-33082, 2020 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-32589836

RESUMEN

The synthesis of new sp-hybridized carbon allotropes is a meaningful and challenging issue. Among the alkynyl carbon family, polyaromatic alkynes is a new branch to be developed. Herein, naphyne with a frame construction of alkynyl-linked naphthyl skeleton was efficiently fabricated through targeted mechanochemical reaction of calcium carbide and perchloronaphthalene. Its unique property and structure with wide alkynyl-naphthyl conjugation, multilayered nanofilm morphology, and high structural stability were corroborated by the comprehensive characterizations combined with computational simulations. Because of these structural features, the as-prepared naphyne can be applied as high-performance binder-free supercapacitor electrode with high specific capacitance (154 F g-1), robust long-term retention (92.1% after 5000 cycles), and prominent electrical conductivity (1490 S m-1). The successful architecture of naphyne approves the feasible synthesis of polyaromatic alkynes and further may provide a prospective approach for the development of alkynyl carbon materials.

9.
ACS Appl Bio Mater ; 3(6): 3809-3816, 2020 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-35025251

RESUMEN

Percutaneous chemical ablation (PCA) is the oldest and most established technique for treating small solid tumors in organs. It has been widely used in clinics even on an outpatient basis. However, compared with the emerging microwave or magnetic hyperthermal ablation, PCA is faced with relatively poor necrosis results and needs to repeat multiple sessions. Inspired by the three effects in the bomb's explosive process, we herein expect to combine calcium carbide (CaC2) nanoparticles into the PCA technique to generate local explosion within tumor tissues, leading to three killing effects against tumors to further improve the ablation efficacy of PCA. Through an efficient wet milling procedure with poly(ethylene glycol), three kinds of nanobombs including CaC2, calcium oxide (CaO), and calcium hydroxide (Ca(OH)2) were fabricated, and they all exhibited desirable suspension stability. Among these nanobombs, in particular CaC2 nanobombs showed a synergistic effect that the generation of ethyne gas bubbles could facilitate the most rapid diffusion of hyperthermia. Also, CaC2 nanobombs offered the powerful ability to cause the sudden rise of local high temperature and pH value. According to the in vivo mice tumor excision trial, the tumors of 75% of cases that received CaC2 treatment were destroyed and eradicated, exhibiting the excellent ablation ability of CaC2 nanobombs against small solid tumors planted in mice.

10.
J Diabetes Metab Disord ; 19(2): 829-848, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33520806

RESUMEN

PURPOSE: The current study aims to determine the molecular mechanisms of diabetic retinopathy (DR) using the protein-protein interactome and metabolome map. We examined the protein network of novel biomarkers of DR for direct (physical) and indirect (functional) interactions using clinical target proteins in different models. METHODS: We used proteomic tools including 2-dimensional gel electrophoresis, mass spectrometry analysis, and database search for biomarker identification using in vivo murine and human model of diabetic retinopathy and in vitro model of oxidative stress. For the protein interactome and metabolome mapping, various bioinformatic tools that include STRING and OmicsNet were used. RESULTS: We uncovered new diabetic biomarkers including prohibitin (PHB), dynamin 1, microtubule-actin crosslinking factor 1, Toll-like receptor (TLR 7), complement activation, as well as hypothetical proteins that include a disintegrin and metalloproteinase (ADAM18), vimentin III, and calcium-binding C2 domain-containing phospholipid-binding switch (CAC2PBS) using a proteomic approach. Proteome networks of protein interactions with diabetic biomarkers were established using known DR-related proteome data. DR metabolites were interconnected to establish the metabolome map. Our results showed that mitochondrial protein interactions were changed during hyperglycemic conditions in the streptozotocin-treated murine model and diabetic human tissue. CONCLUSIONS: Our interactome mapping suggests that mitochondrial dysfunction could be tightly linked to various phases of DR pathogenesis including altered visual cycle, cytoskeletal remodeling, altered lipid concentration, inflammation, PHB depletion, tubulin phosphorylation, and altered energy metabolism. The protein-metabolite interactions in the current network demonstrate the etiology of retinal degeneration and suggest the potential therapeutic approach to treat DR.

11.
mBio ; 9(6)2018 12 18.
Artículo en Inglés | MEDLINE | ID: mdl-30563896

RESUMEN

Human infection with Cryptococcus causes up to a quarter of a million AIDS-related deaths annually and is the most common cause of nonviral meningitis in the United States. As an opportunistic fungal pathogen, Cryptococcus neoformans is distinguished by its ability to adapt to diverse host environments, including plants, amoebae, and mammals. In the present study, comparative transcriptomics of the fungus within human cerebrospinal fluid identified expression profiles representative of low-nutrient adaptive responses. Transcriptomics of fungal isolates from a cohort of HIV/AIDS patients identified high expression levels of an alternative carbon nutrient transporter gene, STL1, to be associated with poor early fungicidal activity, an important clinical prognostic marker. Mouse modeling and pathway analysis demonstrated a role for STL1 in mammalian pathogenesis and revealed that STL1 expression is regulated by a novel multigene regulatory mechanism involving the CAC2 subunit of the chromatin assembly complex 1, CAF-1. In this pathway, the global regulator of virulence gene VAD1 was found to transcriptionally regulate a cryptococcal homolog of a cytosolic protein, Ecm15, in turn required for nuclear transport of the Cac2 protein. Derepression of STL1 by the CAC2-containing CAF-1 complex was mediated by Cac2 and modulated binding and suppression of the STL1 enhancer element. Derepression of STL1 resulted in enhanced survival and growth of the fungus in the presence of low-nutrient, alternative carbon sources, facilitating virulence in mice. This study underscores the utility of ex vivo expression profiling of fungal clinical isolates and provides fundamental genetic understanding of saprophyte adaption to the human host.IMPORTANCECryptococcus is a fungal pathogen that kills an estimated quarter of a million individuals yearly and is the most common cause of nonviral meningitis in the United States. The fungus is carried in about 10% of the adult population and, after reactivation, causes disease in a wide variety of immunosuppressed individuals, including the HIV infected and patients receiving transplant conditioning, cancer therapy, or corticosteroid therapy for autoimmune diseases. The fungus is widely carried in the soil but can also cause infections in plants and mammals. However, the mechanisms for this widespread ability to infect a variety of hosts are poorly understood. The present study identified adaptation to low nutrients as a key property that allows the fungus to inhabit these diverse environments. Further studies identified a nutrient transporter gene, STL1, to be upregulated under low nutrients and to be associated with early fungicidal activity, a marker of poor clinical outcome in a cohort of HIV/AIDS patients. Understanding molecular mechanisms involved in adaptation to the human host may help to design better methods of control and treatment of widely dispersed fungal pathogens such as Cryptococcus.


Asunto(s)
Cryptococcus neoformans/genética , Cryptococcus neoformans/patogenicidad , Redes y Vías Metabólicas/genética , Serina-Treonina Quinasas TOR/genética , Factores de Virulencia/genética , Adulto , Animales , Modelos Animales de Enfermedad , Femenino , Perfilación de la Expresión Génica , Genes Reguladores , Infecciones por VIH/microbiología , Interacciones Huésped-Patógeno/genética , Humanos , Masculino , Proteínas de Transporte de Membrana/genética , Meningitis Criptocócica/líquido cefalorraquídeo , Ratones , Ratones Endogámicos CBA , Persona de Mediana Edad , Ensayos Clínicos Controlados Aleatorios como Asunto , Virulencia , Adulto Joven
12.
ACS Appl Mater Interfaces ; 9(4): 3895-3901, 2017 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-28071888

RESUMEN

The discovery of new carbon materials and the reactive activation of CaC2 are challenging subjects. In this study, a series of alkynyl carbon materials (ACMs) were synthesized by the interfacial mechanochemical reaction of CaC2 with four typical polyhalogenated hydrocarbons. Their properties and structures were characterized, and their electrochemical performances were examined. The reaction was rapid and efficient arising from the intense mechanical activation of CaC2. The ACMs are micro-mesoporous materials with distinct layered structure, specific graphitization degree, and clear existence of sp-C. In addition, the ACMs exhibit high specific capacitance in the range of 57-133 F g-1 and thus can be ideal candidates for active materials used in supercapacitors. The results may imply an alternative synthesis of carbon allotropes, as well as an efficient approach for the activation of CaC2.

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