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1.
Bioprocess Biosyst Eng ; 44(10): 2153-2166, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34057575

RESUMO

Expensive cellulase and complex detoxification procedures increase the cost of biomass lactic acid fermentation. Therefore, it is of great significance to develop a robust method to ferment lactic acid using biomass by avoiding cellulase and detoxification. This study demonstrates the advantage of combining mechanocatalytic P2O5 pre-treatment and strain domestication. We show that an enzyme-free mechanocatalytic saccharification process by combining mix-milling of P2O5 with biomass and successive hydrolysis produces a fermentable hydrolysate with much less inhibitory compounds than the hydrolysates obtained by conventional methods; only 5-HMF, furfural and acetic acid were detected in the biomass hydrolysate, and no phenolic inhibitors were detected. Pretreatment of biomass with P2O5 not only avoided cellulase, but also obtained less toxic hydrolysate. Furthermore, the Pediococcus pentosaceus strain gained superior inhibitor tolerance through domestication. It could tolerate 17.1 g/L acetic acid, 12.5 g/L 5-HMF, 11.9 g/L guaiacol and 11.5 g/L furfural and showed activity in decomposing furfural and 5-HMF for self-detoxification, allowing efficient lactic acid fermentation from biomass hydrolysate without detoxification. The lactic acid concentration and conversion rate fermented by domesticated bacteria were increased by 113.5% and 22.4%, respectively. In addition, the domesticated bacteria could utilize glucose and xylose simultaneously to produce lactic acid selectively. The combination of P2O5 pre-treatment and strain domestication to ferment lactic acid is applied to several biomass feedstocks, including corn stalk, corn stalk residue and rice husk residue. Lactic acid concentrations of 29.8 g/L, 31.1 g/L, and 46.2 g/L were produced from the hydrolysates of corn stalk, corn stalk residue and rice husk residue, respectively.


Assuntos
Ácido Láctico/biossíntese , Pediococcus pentosaceus/efeitos dos fármacos , Compostos de Fósforo/farmacologia , Biomassa , Cromatografia Líquida de Alta Pressão , Fermentação , Hidrólise , Oryza/metabolismo , Espectrofotometria Ultravioleta , Zea mays/metabolismo
2.
Chem Soc Rev ; 50(4): 2260-2279, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33367452

RESUMO

Pnictogens (the non-metal phosphorus, metalloids arsenic and antimony, and metal bismuth) possess diverse chemical characteristics that support the formation of extended molecular structures. As witnessed by the centuries-old (and ongoing) clinical utilities, pnictogen-based compounds have secured their places in history as "magic bullet" therapeutic drugs in medicinal contexts. Moreover, with the development of recent metalloproteomics and bio-coordination chemistry, the pnictogen-based drugs functionally binding to proteins/enzymes in biological systems have been underlaid for "drug repurposing" with promising opportunities. Furthermore, advances in the modern materials science and nonotechnology have stimulated a revolution in other newly discovered forms of pnictogens-phosphorene, arsenene, antimonene, and bismuthine (layered pnictogens). Based on their favorable optoelectronic properties, layered pnictogens have shown dramatic superiority as emerging photonic nanomedicines for the treatment of various diseases. This tutorial review outlines the history and mechanism of action of ancient pnictogen-based drugs (e.g., arsenical compounds in traditional Chinese medicine) and their repurposing into modern therapeutics. Then, the revolutionary use of emerging layered pnictogens as photonic nanomedicines, alongside assessments of their in vivo biosafety, is discussed. Finally, the challenges to further development of pnictogens are set forth and insights for further exploration of their appealing properties are offered. This tutorial review may also provide some deep insights into the fields of integrated traditional Chinese and Western medicines from the perspective of materials science and nanotechnology.


Assuntos
Antimônio/química , Arsenicais/química , Bismuto/química , Nanoestruturas/química , Preparações Farmacêuticas/química , Compostos de Fósforo/química , Animais , Antimônio/farmacologia , Arsenicais/farmacologia , Materiais Biocompatíveis/química , Bismuto/farmacologia , Humanos , Imunoterapia , Estrutura Molecular , Nanomedicina , Dispositivos Ópticos , Compostos de Fósforo/farmacologia , Fototerapia , Ligação Proteica , Radioterapia
3.
Biochem Pharmacol ; 170: 113668, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31628909

RESUMO

Human Vγ9Vδ2 T cells respond to small phosphorus-containing compounds, often called phosphoantigens, which are now known to be intracellular ligands of the immune receptor butyrophilin 3A1 (BTN3A1). In order to compare the efficiency of butyrophilin ligands, we developed a luciferase-based lysis assay that measures the direct cytolysis by Vγ9Vδ2 T cells of luciferase-expressing K562 leukemia cells sensitized by phosphoantigen prodrugs. Our results show that the luciferase-based lysis assay allows in vitro and in vivo assessment of phosphoantigen activity in a way that does not require the extensive processing of flow cytometry or ELISA based approaches. In cellular assays, the structure activity relationships of phosphoantigen prodrugs correlate with ELISA-based activation assays, though phosphoantigen induced target cell lysis occurs at lower concentrations relative to T cell interferon γ production measured by ELISA. In mice dosed with phosphoantigens, a racemic aryl phosphonamidate prodrug, methyl 2-[[[(E)-5-hydroxy-4-methyl-pent-3-enyl]-(1-naphthyloxy)phosphoryl]amino]acetate (1-Nap/GlyOMe C-HMBP, 5), sensitized subcutaneous K562 tumors within minutes, and this effect was maintained at least four hours after treatment. In vivo activity of compound 5 was stronger than that of an equivalent dose of zoledronate. This luciferase lysis assay can be used for evaluation of phosphoantigens due to its time efficiency, high sensitivity, and in vivo compatibility and demonstrates rapid in vitro and in vivo sensitization of tumor cells by phosphoantigen prodrugs.


Assuntos
Leucócitos Mononucleares/enzimologia , Luciferases/metabolismo , Organofosfatos/farmacologia , Pró-Fármacos/farmacologia , Animais , Relação Dose-Resposta a Droga , Humanos , Células K562 , Leucócitos Mononucleares/efeitos dos fármacos , Camundongos , Camundongos da Linhagem 129 , Camundongos Knockout , Organofosfatos/química , Compostos de Fósforo/química , Compostos de Fósforo/farmacologia , Pró-Fármacos/química , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
4.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 53(7): 470-474, 2018 Jul 09.
Artigo em Chinês | MEDLINE | ID: mdl-29996365

RESUMO

Objective: To evaluate the remineralization effect and mechanism of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) with different concentrations of fluorine on demineralized enamel using electronic probe. Methods: Extracted premolar teeth for orthodontic purpose were immersed into lactic acid gel to prepare artificial white spot lesions (10 teeth in each group). Then the specimens were randomly assigned to three groups: Control group, with 5% of the CPP-ACP+deionized water; Group A with 5% CPP-ACP+500 mg/L F(-) and Group B with 5% CPP-ACP+900 mg/L F(-). The teeth in each group were soaked in different solutions for 4 days and then were measured using electron probe tester. The changes of contents among the three groups were compared. Results: No statistically significant difference in the percentage of fluorine was found in the control group before and after treatment (P=0.06), and the difference in the percentage of fluorine quality in the other two groups was statistically significant (P<0.05). Statistically significant difference was found between calcium oxide and phosphorus peroxide in the three groups before and after mineralization (P<0.05). The percentage change of fluorine mass in group B [(0.107±0.035)%] was significantly greater than that in group A [(0.057±0.038)%] (P<0.05), while fluorine mass in group A was significantly greater than that in control group [(0.013±0.019)%] (P<0.05). In group A and group B, the change in quality of calcium oxide and phosphorus peroxide was significantly greater than that in control group (P<0.05), while no significant difference was found between group A and group B (P>0.05). Conclusions: The addition of fluorine in CPP-ACP increased the transport and penetration of calcium, phosphorus and fluorine on enamel surface.


Assuntos
Caseínas/farmacologia , Esmalte Dentário/efeitos dos fármacos , Flúor/administração & dosagem , Remineralização Dentária/métodos , Dente Pré-Molar , Cálcio/farmacocinética , Compostos de Cálcio/farmacologia , Assistência Odontológica , Esmalte Dentário/fisiologia , Microanálise por Sonda Eletrônica/métodos , Flúor/farmacocinética , Flúor/farmacologia , Humanos , Óxidos/farmacologia , Fósforo/farmacocinética , Compostos de Fósforo/farmacologia , Distribuição Aleatória
5.
eNeuro ; 4(4)2017.
Artigo em Inglês | MEDLINE | ID: mdl-28798954

RESUMO

ε-Toxin is a pore forming toxin produced by Clostridium perfringens types B and D. It is synthesized as a less active prototoxin form that becomes fully active upon proteolytic activation. The toxin produces highly lethal enterotoxaemia in ruminants, has the ability to cross the blood-brain barrier (BBB) and specifically binds to myelinated fibers. We discovered that the toxin induced a release of ATP from isolated mice optic nerves, which are composed of myelinated fibers that are extended from the central nervous system. We also investigated the effect of the toxin on compound action potentials (CAPs) in isolated mice optic nerves. When nerves were stimulated at 100 Hz during 200 ms, the decrease of the amplitude and the area of the CAPs was attenuated in the presence of ε-toxin. The computational modelling of myelinated fibers of mouse optic nerve revealed that the experimental results can be mimicked by an increase of the conductance of myelin and agrees with the pore forming activity of the toxin which binds to myelin and could drill it by making pores. The intimate ultrastructure of myelin was not modified during the periods of time investigated. In summary, the acute action of the toxin produces a subtle functional impact on the propagation of the nerve action potential in myelinated fibers of the central nervous system with an eventual desynchronization of the information. These results may agree with the hypothesis that the toxin could be an environmental trigger of multiple sclerosis (MS).


Assuntos
Potenciais de Ação/efeitos dos fármacos , Toxinas Bacterianas/farmacologia , Nervo Óptico/efeitos dos fármacos , Trifosfato de Adenosina/metabolismo , Animais , Clostridium perfringens/química , Simulação por Computador , Estimulação Elétrica , Técnicas In Vitro , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Transmissão , Modelos Biológicos , Nervo Óptico/ultraestrutura , Compostos de Fósforo/farmacologia , Bloqueadores dos Canais de Potássio/farmacologia , Fatores de Tempo
6.
J Inorg Biochem ; 165: 80-91, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27449160

RESUMO

The phosphane Cu(I) complex [Cu(thp)4][PF6], 1 (thp=tris(hydroxymethyl)phosphane) shows notable in vitro antitumour activity against a wide range of solid tumours. Uptake experiments performed in 1-treated colon cancer cells by atomic absorption spectrometry, reveal that the antiproliferative activity is consistent with the intracellular copper content. The solution chemistry of this agent, investigated by means of X-ray Absorption Spectroscopy and spectrophotometric titrations in aqueous media, indicates that 1 is labile giving coordinative unsaturated [Cu(thp)n]+ species (n=3 and 2) at micromolar concentrations. [Cu(thp)n]+ are reactive species that yield the mixed-ligand complex [Cu(thp)2(BCS)]- (BCS: bathocuproinedisulphonate(2-)) upon interaction with N,N-diimine. Analogously, [Cu(thp)n]+ interact with the methionine-rich peptide sequence (Ac-MMMMPMTFK-NH2; Pep1), relevant in the recruiting of physiological copper, giving [Cu(thp)(Pep1)]+ and [Cu(Pep1)]+ species. The formation of these adducts was assessed by electrospray mass spectrometry in the positive ion mode and validated by density functional theory investigations. The possibility to trans-chelate Cu(I) from pure inorganic [Cu(thp)n]+ assemblies into more physiological adducts represents a pathway that complex 1 might follow during the internalization process into cancer cells.


Assuntos
Antineoplásicos , Cobre , Citotoxinas , Neoplasias/tratamento farmacológico , Compostos de Fósforo , Antineoplásicos/química , Antineoplásicos/farmacologia , Células CACO-2 , Quelantes/química , Quelantes/farmacologia , Cobre/química , Cobre/farmacologia , Citotoxinas/química , Citotoxinas/farmacologia , Células HeLa , Células Hep G2 , Humanos , Células MCF-7 , Neoplasias/metabolismo , Neoplasias/patologia , Compostos de Fósforo/química , Compostos de Fósforo/farmacologia
7.
J Clin Endocrinol Metab ; 100(11): 4264-71, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26323022

RESUMO

CONTEXT: Phosphorus-based food additives can substantially increase total phosphorus intake per day, but the effect of these additives on endocrine factors regulating bone and mineral metabolism is unclear. OBJECTIVE: This study aimed to examine the effect of phosphorus additives on markers of bone and mineral metabolism. Design and Setting, and Participants: This was a feeding study of 10 healthy individuals fed a diet providing ∼1000 mg of phosphorus/d using foods known to be free of phosphorus additives for 1 week (low-additive diet), immediately followed by a diet containing identical food items; however, the foods contained phosphorus additives (additive-enhanced diet). Parallel studies were conducted in animals fed low- (0.2%) and high- (1.8%) phosphorus diets for 5 or 15 weeks. MAIN OUTCOME MEASURES: The changes in markers of mineral metabolism after each diet period were measured. RESULTS: Participants were 32 ± 8 years old, 30% male, and 70% black. The measured phosphorus content of the additive-enhanced diet was 606 ± 125 mg higher than the low-additive diet (P < .001). After 1 week of the low-additive diet, consuming the additive-enhanced diet for 1 week significantly increased circulating fibroblast growth factor 23 (FGF23), osteopontin, and osteocalcin concentrations by 23, 10, and 11%, respectively, and decreased mean sclerostin concentrations (P < .05 for all). Similarly, high-phosphorus diets in mice significantly increased blood FGF23, osteopontin and osteocalcin, lowered sclerostin, and decreased bone mineral density (P < .05 for all). CONCLUSIONS: The enhanced phosphorus content of processed foods can disturb bone and mineral metabolism in humans. The results of the animal studies suggest that this may compromise bone health.


Assuntos
Osso e Ossos/metabolismo , Aditivos Alimentares/farmacologia , Minerais/metabolismo , Compostos de Fósforo/farmacologia , Proteínas Adaptadoras de Transdução de Sinal , Adulto , Animais , Biomarcadores/metabolismo , Densidade Óssea/efeitos dos fármacos , Proteínas Morfogenéticas Ósseas/sangue , Osso e Ossos/efeitos dos fármacos , Dieta , Comportamento Alimentar , Feminino , Fator de Crescimento de Fibroblastos 23 , Fatores de Crescimento de Fibroblastos/sangue , Marcadores Genéticos , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Osteocalcina/sangue , Osteopontina/sangue , Adulto Jovem
8.
Water Res ; 76: 53-65, 2015 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-25792434

RESUMO

Members of the Fusarium group were recently detected in water distribution systems of several hospitals in the world. An epidemiological investigation was conducted over 2 years in hospital buildings in Dijon and Nancy (France) and in non-hospital buildings in Dijon. The fungi were detected only within the water distribution systems of the hospital buildings and also, but at very low concentrations, in the urban water network of Nancy. All fungi were identified as Fusarium oxysporum species complex (FOSC) and Fusarium dimerum species complex (FDSC) by sequencing part of the translation elongation factor 1-alpha (TEF-1α) gene. Very low diversity was found in each complex, suggesting the existence of a clonal population for each. Density and heterogeneous distributions according to buildings and variability over time were explained by episodic detachments of parts of the colony from biofilms in the pipes. Isolates of these waterborne populations as well as soilborne isolates were tested for their ability to grow in liquid medium in the presence of increasing concentrations of sodium hypochlorite, copper sulfate, anti-corrosion pipe coating, at various temperatures (4°-42 °C) and on agar medium with amphotericin B and voriconazole. The waterborne isolates tolerated higher sodium hypochlorite and copper sulfate concentrations and temperatures than did soilborne isolates but did not show any specific resistance to fungicides. In addition, unlike waterborne isolates, soilborne isolates did not survive in water even supplemented with glucose, while the former developed in the soil as well as soilborne isolates. We concluded the existence of homogeneous populations of FOSC and FDSC common to all contaminated hospital sites. These populations are present at very low densities in natural waters, making them difficult to detect, but they are adapted to the specific conditions offered by the complex water systems of public hospitals in Dijon and Nancy and probably other localities in the world.


Assuntos
Água Potável/microbiologia , Fusarium/isolamento & purificação , Microbiologia da Água , Abastecimento de Água , Aclimatação , Antifúngicos/farmacologia , Biofilmes , Sulfato de Cobre/farmacologia , França , Fusarium/genética , Fusarium/crescimento & desenvolvimento , Hospitais , Fator 1 de Elongação de Peptídeos/genética , Compostos de Fósforo/farmacologia , Dióxido de Silício/farmacologia , Hipoclorito de Sódio/farmacologia , Microbiologia do Solo , Temperatura
9.
Daru ; 22: 76, 2014 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-25542373

RESUMO

BACKGROUND: Chronic and oral administration of benzylamine improves glucose tolerance. Picolylamine is a selective functional antagonist of the human adenosine A2B receptor. Phosphonic diamide derivatives enhance the cellular permeability and in turn their biological activities. METHODS: A series of heteroaryl phosphonicdiamide derivatives were designed as therapeutics to control and manage type2 diabetes. Initially defined Lipinski parameters encouraged them as safer drugs. Molecular docking of these compounds against Protein tyrosine phosphatase (PTP), the potential therapeutic target of type 2 diabetes, revealed their potential binding ability explaining their anti-diabetic activity in terms of PTP inhibition. Human intestinal absorption, Caco-2 cell permeability, MDCK cell permeability, BBB penetration, skin permeability and plasma protein binding abilities of the title compounds were calculated by PreADMET server. A convenient method has been developed for the synthesis of title compounds through the formation of 1-ethoxy-N,N'-bis(4-fluorobenzyl/pyridin-3-ylmethyl)phosphinediamine by the reaction of 4-fluorobenzylamine/ 3-picolylamine with ethyldichlorophosphite, subsequently reacted with heteroaryl halides using lanthanum(III) chloride as a catalyst. RESULTS: All the compounds exhibited significant in vitro anti-oxidant activity and in vivo evaluation in streptozotocin induced diabetic rat models revealed that the normal glycemic levels were observed on 12(th) day by 9a and 20(th) day by 5b, 5c, 9e and 9f. The remaining compounds also exhibited normal glycemic levels by 25(th) day. CONCLUSION: The results from molecular modeling, in vitro and in vivo studies are suggesting them as safer and effective therapeutic agents against type2 diabetes. Graphical Abstract Development of PTPs inhibitors.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Inibidores Enzimáticos/farmacologia , Hipoglicemiantes/farmacologia , Compostos de Fósforo/farmacologia , Proteínas Tirosina Fosfatases/antagonistas & inibidores , Animais , Antioxidantes/farmacologia , Biomarcadores/sangue , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Barreira Hematoencefálica/metabolismo , Células CACO-2 , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Tipo 2/sangue , Modelos Animais de Doenças , Cães , Desenho de Fármacos , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/metabolismo , Humanos , Hipoglicemiantes/síntese química , Hipoglicemiantes/metabolismo , Absorção Intestinal , Células Madin Darby de Rim Canino , Masculino , Simulação de Acoplamento Molecular , Estrutura Molecular , Permeabilidade , Compostos de Fósforo/síntese química , Compostos de Fósforo/metabolismo , Ligação Proteica , Proteínas Tirosina Fosfatases/metabolismo , Ratos Wistar , Absorção Cutânea , Relação Estrutura-Atividade , Fatores de Tempo
10.
Eur J Med Chem ; 87: 662-76, 2014 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-25305333

RESUMO

A number of novel ansa-spiro-ansa (asa) cyclotetraphosphazenes (1a-5b) was prepared in the range of 63-90 % yields. The structures of the compounds were verified by MS, FTIR, (1)H, (13)C{(1)H} and (31)P{(1)H} NMR, heteronuclear single quantum coherence (HSQC), and heteronuclear multiple-bond correlation (HMBC) techniques. The crystal structures of 1b, 2c and 5a were determined by X-ray crystallography. The compound 2c was analyzed by the changes in the (31)P{(1)H}NMR spectrum in addition of the chiral solvating agent; (R)-(+)-2,2,2-trifluoro-1-(9'-anthryl)-ethanol (CSA), to investigate its stereogenic properties. The result supports that compound 2c was found to be in the racemic mixture. Cyclic voltammetric and chronoamperometric data of the mono-ferrocenyl-spiro-asa-cyclotetraphosphazenes exhibited electrochemically reversible one-electron oxidation of Fe redox centres. The mono-ferrocenyl-spiro-asa compounds (3a-5b) were evaluated for antituberculosis activity against reference strain Mycobacterium tuberculosis H37Rv and M. tuberculosis clinical strain, which is resistant to rifampicin and isoniazid. These compounds appear not to be good candidates for being antituberculosis agents to clinical strains. All of the compounds were screened for antibacterial activities against G(+) and G(-) bacteria, and for antifungal activities against yeast strains. They seem to be more active against Gram positive bacteria than Gram negative. The interactions of the phosphazenes with plasmid DNA and the evaluations for cytotoxic activity against MCF-7 breast cancer cell lines were investigated. The compounds 1b, 2b, 3a and 4a were found to be more effective than Cisplatin against MCF-7 breast cancer cell lines at lower concentrations.


Assuntos
Anti-Infecciosos , Antineoplásicos , Antituberculosos , DNA/efeitos dos fármacos , Compostos de Nitrogênio , Compostos de Fósforo , Anti-Infecciosos/síntese química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Antituberculosos/síntese química , Antituberculosos/química , Antituberculosos/farmacologia , Cristalografia por Raios X , Humanos , Células MCF-7 , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Modelos Moleculares , Estrutura Molecular , Compostos de Nitrogênio/síntese química , Compostos de Nitrogênio/química , Compostos de Nitrogênio/farmacologia , Compostos de Fósforo/síntese química , Compostos de Fósforo/química , Compostos de Fósforo/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier
11.
Colloids Surf B Biointerfaces ; 118: 226-33, 2014 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-24780435

RESUMO

A series of ZrO(2) doped MgO-CaO-SiO(2)-P(2)O(5)-CaF(2) bioactive glass-ceramics were obtained by sintering method. The crystallization behavior, phase composition, morphology and structure of glass-ceramics were characterized. The bending strength, elastic modulus, fracture toughness, micro-hardness and thermal expansion coefficient (TEC) of glass-ceramics were investigated. The in vitro bioactivity and cytotoxicity tests were used to evaluate the bioactivity and biocompatibility of glass-ceramics. The sedimentation mechanism and growth process of apatites on sample surface were discussed. The results showed that the mainly crystalline phases of glass-ceramics were Ca(5)(PO4)3F (fluorapatite) and ß-CaSiO(3). (ß-wollastonite). m-ZrO(2) (monoclinic zirconia) declined the crystallization temperatures of glasses. t-ZrO(2) (tetragonal zirconia) increased the crystallization temperature of Ca(5)(PO4)(3)F and declined the crystallization temperature of ß-CaSiO(3). t-ZrO(2) greatly increased the fracture toughness, bending strength and micro-hardness of glass-ceramics. The nanometer apatites were induced on the surface of glass-ceramic after soaking 28 days in SBF (simulated body fluid), indicating the glass-ceramic has good bioactivity. The in vitro cytotoxicity test demonstrated the glass-ceramic has no toxicity to cell.


Assuntos
Cerâmica/química , Cerâmica/farmacologia , Fenômenos Mecânicos , Zircônio/farmacologia , Animais , Líquidos Corporais/química , Compostos de Cálcio/química , Compostos de Cálcio/farmacologia , Fluoreto de Cálcio/química , Fluoreto de Cálcio/farmacologia , Morte Celular/efeitos dos fármacos , Cristalização , Análise Diferencial Térmica , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Óxido de Magnésio/química , Óxido de Magnésio/farmacologia , Camundongos , Microscopia Eletrônica de Varredura , Óxidos/química , Óxidos/farmacologia , Compostos de Fósforo/química , Compostos de Fósforo/farmacologia , Dióxido de Silício/química , Dióxido de Silício/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Difração de Raios X
12.
Sci Rep ; 4: 4392, 2014 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-24637634

RESUMO

CaO-P2O5-SiO2-B2O3-ZnO bioactive glasses were prepared via an optimized sol-gel method. The current investigation was focused on producing novel zinc based calcium phosphoborosilicate glasses and to evaluate their mechanical, rheological, and biocompatible properties. The morphology and composition of these glasses were studied using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The particle size, mechanical and flexural strength was also determined. Furthermore, the zeta potential of all the glasses were determined to estimate their flocculation tendency. The thermal analysis and weight loss measurements were carried out using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) respectively. For assessing the in-vitro bioactive character of synthesized glasses, the ability for apatite formation on their surface upon their immersion in simulated body fluid (SBF) was checked using SEM and pH measurements. MTS assay cytotoxicity assay and live-dead cell viability test were conducted on J774A.1 cells murine macrophage cells for different glass concentrations.


Assuntos
Durapatita/síntese química , Vidro/química , Silicatos/química , Animais , Materiais Biomiméticos/química , Líquidos Corporais/química , Compostos de Boro/química , Compostos de Boro/farmacologia , Compostos de Cálcio/química , Compostos de Cálcio/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Teste de Materiais , Camundongos , Óxidos/química , Óxidos/farmacologia , Transição de Fase , Compostos de Fósforo/química , Compostos de Fósforo/farmacologia , Silicatos/farmacologia , Dióxido de Silício/química , Dióxido de Silício/farmacologia , Alicerces Teciduais , Óxido de Zinco/química , Óxido de Zinco/farmacologia
13.
Mol Pharm ; 10(9): 3484-96, 2013 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-23898892

RESUMO

The purpose of this manuscript is to study the toxic responses against murine embryonic hippocampal cells (mHippoE-18) and neuroblastoma cells (N2a) to treatment with cationic phosphorus dendrimers (CPD). Two low generations of CPD--generation 2 (G2) and generation 3 (G3)--were applied to cell cultures to monitor events leading to either apoptosis or necrosis. These processes were analyzed using several bioassays, which included the detection of reactive oxygen species (ROS), mitochondrial membrane potential (ΔΨm) alterations, morphology changes, apoptotic and dead cells, cytochrome c (Cyt c) release, caspase 3 activity, DNA fragmentation, as well as changes in cell cycle phases distribution. The results showed that CPD became highly cytotoxic at concentrations above 1 µM and at 0.7 µM in the case of G3 for mHippoE-18 cells. The toxicity was manifested by a pronounced decrease in cell viability, which is correlated with disturbances in cellular activities, such as massive ROS generation. The breakdown of cellular processes leads mainly to the necrotic cell death. Our findings are of high importance in the context of further biomedical studies on CPD.


Assuntos
Cátions/química , Dendrímeros/farmacologia , Compostos de Fósforo/farmacologia , Animais , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Dendrímeros/química , Citometria de Fluxo , Camundongos , Necrose/induzido quimicamente , Compostos de Fósforo/química , Espécies Reativas de Oxigênio/metabolismo
14.
Pak J Biol Sci ; 16(17): 871-6, 2013 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-24498841

RESUMO

This study aimed to evaluate under field conditions the efficiency in the use ofN coated with urease inhibitor in maize. The experiment was conducted in the year of 2007/2008. The experimental design was a randomized block design in a factorial 2 x 6, with five repetitions, constituted the N sources (common and coated with urease inhibitor) and levels (0, 40, 80, 120, 160 and 200 kg ha-1 of N) sidedressing nitrogen application in the growth stage V4. Based on the data obtained were determined recovery efficiencies, utilization, agronomic and physiological N applied. In all cases, the efficiency levels for maize were influenced by levels of sidedressing nitrogen application, in which increasing levels of N resulted in a decrease of the efficiencies, regardless of the source being common urea or coated with urease inhibitor.


Assuntos
Produtos Agrícolas/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Fertilizantes , Nitrogênio/farmacologia , Proteínas de Plantas/antagonistas & inibidores , Urease/antagonistas & inibidores , Zea mays/efeitos dos fármacos , Produtos Agrícolas/enzimologia , Produtos Agrícolas/crescimento & desenvolvimento , Nitrogênio/metabolismo , Óxidos/metabolismo , Óxidos/farmacologia , Compostos de Fósforo/metabolismo , Compostos de Fósforo/farmacologia , Proteínas de Plantas/metabolismo , Compostos de Potássio/metabolismo , Compostos de Potássio/farmacologia , Ureia/metabolismo , Ureia/farmacologia , Urease/metabolismo , Zea mays/enzimologia , Zea mays/crescimento & desenvolvimento
15.
Eur J Med Chem ; 52: 213-20, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22483088

RESUMO

In the present study, a number of new dispirobino and dispiroansa spermine derivatives of cyclotriphosphazene (8-10, 13) were synthesized and characterized by elemental analysis, mass spectrometry, (1)H and (31)P NMR spectroscopy. At first, in vitro cytotoxic activity of cyclotriphosphazene compounds (1-14) against HT-29 (human colon adenocarcinoma), Hep2 (Human epidermoid larynx carcinoma), and Vero (African green monkey kidney) cell lines was investigated. Our study showed that most of these compounds stimulate apoptosis and they have cytotoxic effects for HT-29 and Hep2 cells. Additionally, these compounds (1-14) were investigated for their antibacterial activity against gram-positive (Staphylococcus aureus), gram-negative (Escherichia coli, Pseudomonas aeruginosa) bacteria and for their antifungal activity against Candida albicans, and were shown to be inactive.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Técnicas de Química Sintética , Compostos de Fósforo/síntese química , Animais , Antineoplásicos/química , Antineoplásicos/toxicidade , Bactérias/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Linhagem Celular , Humanos , Concentração Inibidora 50 , Testes de Sensibilidade Microbiana , Compostos de Fósforo/química , Compostos de Fósforo/farmacologia , Compostos de Fósforo/toxicidade
16.
J Comput Neurosci ; 32(1): 119-36, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21667154

RESUMO

In this paper a modular model of the GnRH neuron is presented. For the aim of simplicity, the currents corresponding to fast time scales and action potential generation are described by an impulsive system, while the slower currents and calcium dynamics are described by usual ordinary differential equations (ODEs). The model is able to reproduce the depolarizing afterpotentials, afterhyperpolarization, periodic bursting behavior and the corresponding calcium transients observed in the case of GnRH neurons.


Assuntos
Potenciais de Ação/fisiologia , Hormônio Liberador de Gonadotropina/metabolismo , Modelos Neurológicos , Neurônios/fisiologia , Potenciais de Ação/genética , Animais , Biofísica , Cálcio/metabolismo , Dendritos/fisiologia , Estimulação Elétrica , Hormônio Liberador de Gonadotropina/genética , Proteínas de Fluorescência Verde/genética , Hipotálamo/citologia , Técnicas In Vitro , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neurônios/metabolismo , Técnicas de Patch-Clamp , Compostos de Fósforo/farmacologia , Canais de Potássio/metabolismo , Potenciais Sinápticos/genética , Potenciais Sinápticos/fisiologia
17.
Eur J Med Chem ; 45(11): 5130-9, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20801550

RESUMO

Some new phosphorus(V) hydrazides 1a-12a were synthesized and characterized by (1)H, (13)C, (31)P NMR, IR spectroscopy and elemental analysis. Moreover, the interaction of Cu(M)(2)·nH(2)O with 1a, 3a and 7a gave 4,4'-bis(morpholine)diazene (1b). In fact, in these reactions, copper(II) ions acted as oxidizing agent. The results supported the proposed mechanism. The structures of compounds 1a, 1b and 1c were further determined by X-ray crystallography. Compounds 1a-12a were screened for their antibacterial activities. Also, the acetyl- and butyrylcholinesterase inhibitory activity of 1a, 3a, 7a, 11a and 12a was measured using Ellman's method. It is interesting that these compounds were more potent inhibitors of BChE than of AChE. Also, using Lineweaver-Burk plots, it was indicated these compounds are mixed inhibitors.


Assuntos
Antibacterianos/síntese química , Antibacterianos/farmacologia , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/farmacologia , Compostos de Fósforo/síntese química , Compostos de Fósforo/farmacologia , Acetilcolinesterase/efeitos dos fármacos , Antibacterianos/química , Butirilcolinesterase/efeitos dos fármacos , Inibidores da Colinesterase/química , Cristalografia por Raios X , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Oxirredução , Fósforo/química , Compostos de Fósforo/química , Espectrofotometria Infravermelho
18.
Eur J Med Chem ; 44(11): 4539-46, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19615792

RESUMO

Some new thiadiaza/triazaphospholes, thiadiaza/triaza/tetrazaphosphinines and thiadiaza/tetrazaphosphepines fused with 6-methyl-1,2,4-triazin-5-one moiety were synthesized via reactions of alpha,beta-bifunctional compounds derived from 4-amino-3-mercapto-6-methyl-1,2,4-triazin-5(4H)-one (1) with various phosphorus reagents. The in vitro antibacterial activities of the synthesized compounds were evaluated against some bacterial strains. Compounds 16 and 21 exhibited good inhibitory activities against most the tested organisms with MIC values in the range 6.25-12.5 microg/mL and lower cytotoxicity in comparison with the reference drugs.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Compostos de Fósforo/química , Compostos de Fósforo/farmacologia , Triazinas/química , Triazinas/farmacologia , Animais , Antibacterianos/síntese química , Artemia/efeitos dos fármacos , Bioensaio , Testes de Sensibilidade Microbiana , Estrutura Molecular , Compostos de Fósforo/síntese química , Relação Estrutura-Atividade , Triazinas/síntese química
19.
Exp Brain Res ; 169(1): 126-9, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16369784

RESUMO

Physiological activity-dependent long-term changes in synaptic transmission, as long-term potentiation (LTP) are thought to be the substrate of learning and memory. However, a form of postsynaptic pathological LTP at the CA3-CA1 synapses has been demonstrated following few minutes of anoxia and aglycemia in vitro. The ischemia LTP shared many molecular mechanisms with the physiological LTP, and was believed to be involved in the delayed neuronal death following ischemia. However, the role of the presynaptic component in this regard is not known. Here we show that a short period of oxygen-glucose deprivation can induce a form of LTP (lasting for hours) of the presynaptic response at the CA3-CA1 synapses. This form of LTP is independent of postsynaptic alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) and N-methyl-D-aspartate (NMDA) receptors, but Ca(2+) dependent. This presynaptic LTP may represent a presynaptic hyperexcitability of the afferent fibers following ischemia, and responsible for the excitotoxicity to the CA1 neurons (ischemia-induced increases of glutamate release that kills neurons) and the postsynaptic pathological ischemic LTP.


Assuntos
Glucose/deficiência , Hipocampo/fisiopatologia , Hipóxia/fisiopatologia , Potenciação de Longa Duração/fisiologia , Sinapses/fisiologia , 6-Ciano-7-nitroquinoxalina-2,3-diona/farmacologia , Animais , Cálcio/metabolismo , Relação Dose-Resposta à Radiação , Estimulação Elétrica/métodos , Antagonistas de Aminoácidos Excitatórios/farmacologia , Hipocampo/citologia , Técnicas In Vitro , Potenciação de Longa Duração/efeitos da radiação , Compostos de Fósforo/farmacologia , Ratos , Ratos Sprague-Dawley , Sinapses/efeitos da radiação , Tetrodotoxina/farmacologia , Fatores de Tempo
20.
Zhonghua Shao Shang Za Zhi ; 21(5): 363-6, 2005 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-16383040

RESUMO

OBJECTIVE: To explore the bio-inductive effects of inorganic elements (Dermlin) on the human epithelial proliferation and differentiation and their promoting effects on skin wound healing. METHODS: 1 ). Cellular test: Normal human skin epithelial cells were cultured with 20 g/L Dermlin supplemented culture medium (E group) and regular culture medium (C group), respectively. The cell proliferation rate and the expressions of type IV collagen and epidermal growth factor (EGF) in the supernatant were determined in 12 and 20 post culture days (PCD). (2). Animal test: Self-consubstantiality control was employed in the study. Sixty Sprague - Dawley rats were inflicted with two symmetric 10% TBSA of superficial or deep partial thickness scald on the back of each rat, and were divided into control[ C, with topical application of silver sulfadiazine (SD - Ag) cream to the wounds] and treatment (T, with 1 g/100 cm2 Dermlin topical application to the wounds) groups. The pathological changes in wound skin were observed and the wound healing rate was calculated on 3, 5, 7, 10, 14 and 18 post treatment day (PTD). (3). Randomized, double-blinded and consubstantiality control method was employed in the clinical trial. Ninety patients were enrolled in the clinical study, among them 30 cases with 60 donor site wounds, 30 with 60 superficial and 30 with 60 deep partial thickness burn wounds were included. Dermlin in dose of 1 g/100 cm2 was applied to the wounds in T group and SD - Ag cream in C group for up to 18 days. Furthermore, sixty patients with diabetic foot ulcers were included for 1 g/100 cm2 Dermlin treatment. The wound healing rate was observed. And the blood and urine test and the indices of hepatic and renal function were determined. RESULTS: 1). Cellular test: The cell proliferation rate and the expression of type IV collagen and EGF in the culture supernatant were obviously higher than those in control group at the same time points (P < 0.01). 2). Animal test: Hyperplastic granulation tissue occurred in the rat wound in the T group since 5 PTD, while that occurred in the C group since 7 PTD. The healing rate of superficial thickness wound in T group on 7, 10, 14 PTD, and that of deep partial thickness wound in T group on 5, 10, 18 PTD were obviously higher than that in the C group (P <0.05). 3). Clinical study indicated that the wound healing rate of the patients with superficial or deep partial thickness scald in the T group was evidently higher than that in the C group on 5 and 10 PTD (P <0.05), but the wound healing time of the superficial, deep partial thickness wound and donor site wound in the T group was significantly shorter than that in the C group (P < 0.05). Before treatment, the square of the ulcers on the foot of the patients with diabetic was (39 +/- 28) cm2, and it was reduced to (19 +/- 23) cm2 2 weeks later, with the therapeutic efficacy reaching 62.5% . For all patients, no obvious change was found in the blood test and hepatic and renal function indices. CONCLUSION: The inorganic element (Dermlin) is beneficial to wound healing and to the proliferation and differentiation of epithelial cells.


Assuntos
Pé Diabético/tratamento farmacológico , Compostos Inorgânicos/farmacologia , Compostos de Fósforo/farmacologia , Cicatrização/efeitos dos fármacos , Adolescente , Adulto , Animais , Queimaduras/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Modelos Animais de Doenças , Método Duplo-Cego , Epitélio , Humanos , Compostos Inorgânicos/uso terapêutico , Masculino , Compostos de Fósforo/uso terapêutico , Ratos , Ratos Sprague-Dawley , Pele/efeitos dos fármacos , Pele/fisiopatologia
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