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3.
Plant Physiol Biochem ; 208: 108529, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38507837

RESUMO

Chromium is a serious heavy metal (HM) and its concentration in plant-soil interface is soaring due to anthropogenic activities, unregulated disposals, and lack of efficient treatments. High concentration of Cr is toxic to ecosystems and human health. Cr stress also diminishes the plant performance by changing the plant's vegetative and reproductive development that ultimately affects sustainable crop production. Silicon (Si) is the second-most prevalent element in the crust of the planet, and has demonstrated a remarkable potential to minimize the HM toxicity. Amending soils with Si mitigates adverse effects of Cr by improving plant physiological, biochemical, and molecular functioning and ensuring better Cr immobilization, compartmentation, and co-precipitation. However, there is no comprehensive review on the role of Si to mitigate Cr toxicity in plants. Thus, in this present review; the discussion has been carried on; 1) the source of Cr, 2) underlying mechanisms of Cr uptake by plants, 3) how Si affects the plant functioning to reduce Cr toxicity, 4) how Si can cause immobilization, compartmentation, and co-precipitation 5) strategies to improve Si accumulation in plants to counter Cr toxicity. We also discussed the knowledge gaps and future research needs. The present review reports up-to-date knowledge about the role of Si to mitigate Cr toxicity and it will help to get better crop productivity in Cr-contaminated soils. The findings of the current review will educate the readers on Si functions in reducing Cr toxicity and will offer new ideas to develop Cr tolerance in plants through the use of Si.


Assuntos
Metais Pesados , Poluentes do Solo , Antioxidantes , Cromo/toxicidade , Ecossistema , Metais Pesados/química , Silício/farmacologia , Poluentes do Solo/toxicidade , Poluentes do Solo/química
4.
ACS Omega ; 9(11): 13041-13050, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38524408

RESUMO

The increased concentration of lead (Pb) in soils is a serious threat to human beings and plants all over the world. Salinity stress is also a major issue across the globe, which limits crop productivity. The use of allelochemicals has become an effective strategy to mitigate the toxic effects of abiotic stresses. Sorghum is an important crop grown across the globe, and it also possesses an appreciably allelopathic potential. Therefore, this study was planned to determine the impacts of the sorghum water extract (SWE) on improving maize growth under Pb and salinity stress. The experiment included different treatments; control, SWE (3%), and different levels of Pb and salinity stress; T1: control, T2: 50 mM NaCl, T3: 100 mM NaCl, T4: 250 µM Pb, and T5: 500 µM Pb. Lead and salinity stress reduced the maize growth by the genesis of reactive oxygen species (ROS), as evidenced by higher production of malondialdehyde (MDA: 39.1 and 32.28%) and hydrogen peroxide (H2O2: 20.62 and 17.81%). Spraying plants with SWE improved the maize growth by increasing antioxidant activities (ascorbate peroxidase: APX, catalase: CAT, peroxidase: POD and superoxide dismutase: SOD), photosynthetic pigments, relative water contents (RWC), osmolyte accumulation (proline, total soluble proteins: TSP, free amino acids: FAA), potassium accumulation, and decreasing MDA, H2O2, sodium, chloride, and Pb accumulation. In conclusion, the application of SWE mitigates adverse impacts of Pb and salinity stresses by improving chlorophyll synthesis and osmolyte accumulation, activating the antioxidant defense system, and preventing the entry of toxic ions.

5.
Food Chem ; 353: 129298, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-33711703

RESUMO

In order to investigate the correlation between free radical scavenging effect and the related molecular structures of active substances in the Haihong fruit (Malus Micromalus Makino) wine, sixteen kinds of components were isolated from the fruit wine. The structures of thirteen components were identified by UV, FTIR, LC-MS, 1D-NMR and 2D-NMR. The scavenging abilities of the fruit wine on DPPH (2,2-Diphenyl-1 -picrylhydrazyl radical), OH, O2- and the protective effects on red blood cell, SOD (Superoxide Dismutase), CAT(Catalase) and GPX(glutathione peroxidases) in aging mice tissues were studied. Results showed that the structures of o-diphenol and m-diphenol play an important role in scavenging free radicals. A larger conjugation system in functional molecule is conducive to getting a higher scavenging rate of free radicals. When the chemical shift of phenol hydrogen is lower, the anti-oxygenation ability is stronger. The fruit wine exhibits a strong scavenging ability on free radicals. It can inhibit the damage of red blood cells caused by OH radical.


Assuntos
Malus/química , Vinho/análise , Animais , Antioxidantes/química , Compostos de Bifenilo/química , Feminino , Radicais Livres/química , Frutas/química , Masculino , Camundongos , Estrutura Molecular , Fenóis/química , Compostos Orgânicos Voláteis/química
6.
Hematol Oncol ; 38(3): 272-276, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32083758

RESUMO

The efficacy and safety of Epstein-Barr virus (EBV)-specific antigen peptide-activated cytotoxic T lymphocytes (CTLs) in the treatment of refractory or recurrent angioimmunoblastic T-cell lymphoma (AITL) was determined in this prospective one-arm clinical study. Seven males and two females were enrolled with a median age of 70 years. The tumor stages were all stage III and IV. All patients had group B symptoms and IPI scores of 3 to 5 points. All patients received chemotherapy before CTLs infusion which the median chemotherapy cycle was three. The diseases states before CTLs included five cases of disease progression (PD), two cases of recurrence (R), and two cases with residual lesions after chemotherapy. Eight patients received HLA-haploidentical EBV-specific CTLs, and one patient chose autologous CTLs. The number of transfused cells was 1.67 to 2.38 × 1010 for one course of CTLs therapy. One patient was treated with three courses of CTLs, three patients were treated with two courses of CTLs, and five patients were treated with one course of CTLs. During the infusion, eight patients had fever, one patient had rash, and no graft-vs-host diseases were observed. The EBV-DNA decreased by more than two orders of magnitude in six patients, and the response rate was 66.7%. Two patients of PD status achieved complete remission (CR), one patient of PD status achieved partial remission, two patients with residual lesions after chemotherapy achieved CR, and four patients had no response. The objective remission rate was 55.6%. After the median follow-up of 14.5 months, five patients died, and three patients were completely relieved while one patient was lost during follow-up. The 3-year overall survival was 44.4% and 3-year progression-free survival was 33.3%. EBV-specific antigen peptide-activated CTLs showed positive effect in certain patients with refractory and recurrent AITL with high clinical safety.


Assuntos
Imunoterapia/métodos , Linfoma de Células T/terapia , Recidiva Local de Neoplasia/terapia , Fragmentos de Peptídeos/imunologia , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/transplante , Proteínas da Matriz Viral/imunologia , Adulto , Idoso , Resistencia a Medicamentos Antineoplásicos , Feminino , Seguimentos , Humanos , Linfoma de Células T/imunologia , Linfoma de Células T/patologia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/imunologia , Recidiva Local de Neoplasia/patologia , Prognóstico , Estudos Prospectivos , Indução de Remissão , Terapia de Salvação
7.
Int J Pharm ; 469(1): 23-30, 2014 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-24751344

RESUMO

Hydrochloric thiothixene (HT) is an antipsychotic drug used in the treatment of various psychoses including schizophrenia, mania, polar disorder, and in behavior disturbances. However, because the psychotics often could not control their behaviors, the independent administration of antipsychotic drug based on medical order was difficult. The omissions of the administration often brought an unsatisfactory therapeutic efficacy. A novel injectable long-term control-released in situ gel of HT for the treatment of schizophrenia was developed based on biodegradable material polylactic acid (PLA). The optimum formulation of the injectable PLA-based HT in situ gel containing 15% (w/w) HT and 45% (w/w) PLA with benzyl benzoate was used as a gelling solvent. The results of the in vitro and in vivo studies showed that this in situ gel had a long-term period of drug release for several weeks and a good histocompatibility without any remarkable inflammatory reactions.


Assuntos
Antipsicóticos/química , Portadores de Fármacos , Ácido Láctico/química , Polímeros/química , Esquizofrenia/tratamento farmacológico , Tiotixeno/química , Animais , Antipsicóticos/administração & dosagem , Antipsicóticos/sangue , Antipsicóticos/farmacocinética , Benzoatos/química , Química Farmacêutica , Preparações de Ação Retardada , Géis , Humanos , Injeções Intramusculares , Masculino , Poliésteres , Ratos Wistar , Solubilidade , Tecnologia Farmacêutica/métodos , Tiotixeno/administração & dosagem , Tiotixeno/sangue , Tiotixeno/farmacocinética
8.
Drug Dev Ind Pharm ; 40(10): 1402-10, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23944837

RESUMO

The purpose of the present study was to optimize the formulations of the thermoresponsive ophthalmic in situ gels of a poorly water-soluble drug fluconazole (FLU) and evaluate the in vitro and in vivo properties of the formulations. The thermoresponsive ophthalmic FLU in situ gels were prepared by mixing FLU, Poloxamer407, Tween80, benzalkonium chloride and carbopol934 in borate buffer solution. The in vivo eye irritation tests and ophthalmic absorption were carried out in rabbits. The formulation compositions influenced the physicochemical properties of FLU in situ gels. The amount of poloxamer407 in the formulation was the main factor that affected the sol-gel transition temperature of the products. Tween80 not only improved the solubility of the FLU but also affected the products' sol-gel transition temperature. In this study, sol-gel transition temperature was not affected by carbopol934. However, carbopol934 affected pH value, transparency and gelling capacity of the products. The product of the optimized formulation was a pseudoplastic fluid and its sol-gel transition temperature was 30.6 ± 1.2 °C. The autoclaving test showed that the sol-gel transition temperature, the flow ability and the flow behavior of the test samples did not change obviously after autoclaving sterilization at 121 °C and 15 psi for 20 min, thus the autoclaving was an acceptable sterilization method for this preparation. The thermoresponsive ophthalmic FLU in situ gels' in vivo ophthalmic absorption was superior to the conventional FLU eye drop. In conclusion, the thermoresponsive ophthalmic FLU in situ gel is a better alternative than the FLU eye drop.


Assuntos
Antifúngicos/administração & dosagem , Excipientes/química , Fluconazol/administração & dosagem , Acrilatos/química , Administração Oftálmica , Animais , Antifúngicos/química , Antifúngicos/farmacocinética , Compostos de Benzalcônio/química , Química Farmacêutica , Feminino , Fluconazol/química , Fluconazol/farmacocinética , Géis , Concentração de Íons de Hidrogênio , Masculino , Soluções Oftálmicas , Poloxâmero/química , Polissorbatos/química , Coelhos , Solubilidade , Esterilização , Temperatura , Temperatura de Transição
9.
Drug Dev Ind Pharm ; 40(1): 9-16, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23317337

RESUMO

BACKGROUND: In the system of the iontophoresis, the external electric field made the ions in the system moving directly, then, the current was generated. Because the current was contributed by all ions in the system, and the small ions with large amount often had higher conductibility than the drug ions, the fraction of the total current contributed by the drug ions was often low. It was the main reason for the generally low efficiency of the transdermal iontophoretic drug delivery. OBJECTIVES: The objective of this study was to find a novel method to increase the fraction of the total current contributed by the drug ions so as to enhance the drug's iontophoretic delivery. METHOD: Iontophoretic transport of nefopam hydrochloride solution and iontophoretic transport of nefopam assisted by ion-exchange materials, including ion-exchange resin, ion-exchange membrane and ion-exchange fiber, across the rat skin were investigated. RESULTS: Both in vitro and in vivo iontophoretic transport experiments showed that the efficiency of the nefopam-fiber iontophoretic system for nefopam permeating across rat skin was the highest among four iontophoretic systems (nefopam solution, nefopam-resin, nefopam-membrane and nefopam-fiber). CONCLUSION: The results of this study suggested that there was an enhancement of nefopam across rat skin by ion-exchange fibers in ion-exchange fibers assisted iontophoresis. The present study has demonstrated the potential of a new approach of using ion-exchange fibers to improve the efficiency of the transdermal iontophoresis for cationizable drugs.


Assuntos
Analgésicos não Narcóticos/farmacocinética , Iontoforese/métodos , Nefopam/farmacocinética , Absorção Cutânea , Administração Cutânea , Analgésicos não Narcóticos/administração & dosagem , Animais , Transporte Biológico , Sistemas de Liberação de Medicamentos , Troca Iônica , Resinas de Troca Iônica/química , Masculino , Nefopam/administração & dosagem , Permeabilidade , Ratos , Ratos Wistar , Pele/metabolismo
10.
Exp Parasitol ; 113(3): 174-8, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16554050

RESUMO

AIM: The present study investigated the processes of macrogametogenesis and oocyst formation of Eimeria tenella (Xiamen strain), including the formation of wall-forming body1 (WFB1) and wall-forming body 2 (WFB2), the club-shape body and the origin of the residual body during the transformation from a macrogamete to an oocyst. METHOD: Transmission electron microscopy was used to follow ultrastructural changes of the organelles during parasite development. Frozen section techniques and special staining were used to determine the chemical composition of the club-shape body. RESULTS: Electron lighter WFB1 appeared earlier than the electron denser WFB2 during the process of cyst wall formation. WFB2 appeared to play a key role in cyst wall formation, whereas WFB1 may have a limited role in the wall-forming process. When two last generation merozoites entered the same host cell simultaneously, one of them grew well, but the other one was developmentally retarded, and became a residual body. Our study indicates that the content of the club-shape body are lipoidal in nature, not amyolpectin as suggested previously, because they stained black by Sudan black-B. CONCLUSIONS: During of macrogametogenesis and oocyst formation of E. tenella (Xiamen strain), WFB2 plays a major role in cyst wall formation. The residual bodies come from the undeveloped macrogametes. The club-body is lipoid; and lipometabolism is important energy resource in E. tenella development.


Assuntos
Eimeria tenella/crescimento & desenvolvimento , Animais , Compostos Azo , Galinhas , Corantes , Eimeria tenella/ultraestrutura , Secções Congeladas , Microscopia Eletrônica de Transmissão , Naftalenos , Oocistos/crescimento & desenvolvimento , Oocistos/ultraestrutura
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