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1.
Eur J Pain ; 22(9): 1685-1690, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29797679

RESUMO

Parathyroid hormone-related peptide (PTHrP) is associated with advanced tumor growth and metastasis, especially in breast, prostate and myeloma cancers that metastasize to bones, resulting in debilitating chronic pain conditions. Our recent studies revealed that the receptor for PTHrP, PTH1R, is expressed in mouse DRG sensory neurons, and its activation leads to flow-activation and modulation of TRPV1 channel function, resulting in peripheral heat and mechanical hypersensitivity. In order to verify the translatability of our findings in rodents to humans, we explored whether this signalling axis operates in primary human DRG sensory neurons. Analysis of gene expression data from recently reported RNA deep sequencing experiments performed on mouse and human DRGs reveals that PTH1R is expressed in DRG and tibial nerve. Furthermore, exposure of cultured human DRG neurons to PTHrP leads to slow-sustained activation of TRPV1 and modulation of capsaicin-induced channel activation. Both activation and modulation of TRPV1 by PTHrP were dependent on PKC activity. Our findings suggest that functional PTHrP/PTH1R-TRPV1 signalling exists in human DRG neurons, which could contribute to local nociceptor excitation in the vicinity of metastatic bone tumor microenvironment.


Assuntos
Gânglios Espinais/metabolismo , Dor/etiologia , Proteína Relacionada ao Hormônio Paratireóideo/metabolismo , Células Receptoras Sensoriais/metabolismo , Canais de Cátion TRPV/metabolismo , Adulto , Animais , Capsaicina/farmacologia , Técnicas de Cultura de Células , Feminino , Gânglios Espinais/patologia , Humanos , Masculino , Camundongos , Dor/fisiopatologia , Transdução de Sinais/efeitos dos fármacos , Adulto Jovem
5.
Sci Total Environ ; 485-486: 263-269, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24727044

RESUMO

Nanoscale photocatalysts have attracted much attention due to their high surface area to volume ratios. However, due to extremely high reactivity, TiO2 and ZnO nanoparticles prepared using different methods tend to either react with surrounding media or agglomerate, resulting in the formation of much larger flocs and significant loss in reactivity. This work investigates the photocatalytic degradation of carbamazepine (CBZ), a persistent pharmaceutical compound from wastewater (WW) using TiO2 and ZnO nanoparticles prepared in the presence of a water-soluble whey powder as stabilizer. The TiO2 and ZnO nanoparticles prepared in the presence of whey stabilizer displayed much less agglomeration and greater degradation power than those prepared without a stabilizer. Higher photocatalytic degradation of carbamazepine was observed (100%) by using whey stabilized TiO2 nanoparticles with 55 min irradiation time as compared to ZnO nanoparticles (92%). The higher degradation of CBZ in wastewater by using TiO2 nanoparticles as compared to ZnO nanoparticles was due to formation of higher photo-generated holes with high oxidizing power of TiO2. The photocatalytic capacity of ZnO anticipated as similar to that of TiO2 as it has the same band gap energy (3.2 eV) as TiO2. However, in the case of ZnO, photocorrosion frequently occurs with the illumination of UV light and this phenomenon is considered as one of the main reasons for the decrease of ZnO photocatalytic activity in aqueous solutions. Further, the estrogenic activity of photocatalyzed WW sample with CBZ and its by-products was carried out by yeast estrogen screen (YES) assay method. Based upon the YES test results, none of the samples showed estrogenic activity.


Assuntos
Carbamazepina/química , Proteínas do Leite/química , Nanoestruturas/química , Titânio/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Óxido de Zinco/química , Carbamazepina/análise , Processos Fotoquímicos , Titânio/análise , Raios Ultravioleta , Águas Residuárias/química , Poluentes Químicos da Água/análise , Proteínas do Soro do Leite , Óxido de Zinco/análise
6.
Sci Total Environ ; 470-471: 58-75, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24140682

RESUMO

Pharmaceutically active compounds (PhACs) are considered as emerging environmental problem due to their continuous input and persistence to the aquatic ecosystem even at low concentrations. Among them, carbamazepine (CBZ) has been detected at the highest frequency, which ends up in aquatic systems via wastewater treatment plants (WWTPs) among other sources. The identification and quantification of CBZ in wastewater (WW) and wastewater sludge (WWS) is of major interest to assess the toxicity of treated effluent discharged into the environment. Furthermore, WWS has been subjected for re-use either in agricultural application or for the production of value-added products through the route of bioconversion. However, this field application is disputable due to the presence of these organic compounds and in order to protect the ecosystem or end users, data concerning the concentration, fate, behavior as well as the perspective of simultaneous degradation of these compounds is urgently necessary. Many treatment technologies, including advanced oxidation processes (AOPs) have been developed in order to degrade CBZ in WW and WWS. AOPs are technologies based on the intermediacy of hydroxyl and other radicals to oxidize recalcitrant, toxic and non-biodegradable compounds to various by-products and eventually to inert end products. The purpose of this review is to provide information on persistent pharmaceutical compound, carbamazepine, its ecological effects and removal during various AOPs of WW and WWS. This review also reports the different analytical methods available for quantification of CBZ in different contaminated media including WW and WWS.


Assuntos
Carbamazepina/química , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Poluentes Químicos da Água/química , Analgésicos não Narcóticos/análise , Analgésicos não Narcóticos/química , Carbamazepina/análise , Monitoramento Ambiental , Oxirredução , Esgotos/química , Poluentes Químicos da Água/análise
9.
Mol Psychiatry ; 18(10): 1077-89, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23711981

RESUMO

Autism spectrum disorders (ASDs) have been suggested to arise from abnormalities in the canonical and non-canonical Wnt signaling pathways. However, a direct connection between a human variant in a Wnt pathway gene and ASD-relevant brain pathology has not been established. Prickle2 (Pk2) is a post-synaptic non-canonical Wnt signaling protein shown to interact with post-synaptic density 95 (PSD-95). Here, we show that mice with disruption in Prickle2 display behavioral abnormalities including altered social interaction, learning abnormalities and behavioral inflexibility. Prickle2 disruption in mouse hippocampal neurons led to reductions in dendrite branching, synapse number and PSD size. Consistent with these findings, Prickle2 null neurons show decreased frequency and size of spontaneous miniature synaptic currents. These behavioral and physiological abnormalities in Prickle2 disrupted mice are consistent with ASD-like phenotypes present in other mouse models of ASDs. In 384 individuals with autism, we identified two with distinct, heterozygous, rare, non-synonymous PRICKLE2 variants (p.E8Q and p.V153I) that were shared by their affected siblings and inherited paternally. Unlike wild-type PRICKLE2, the PRICKLE2 variants found in ASD patients exhibit deficits in morphological and electrophysiological assays. These data suggest that these PRICKLE2 variants cause a critical loss of PRICKLE2 function. The data presented here provide new insight into the biological roles of Prickle2, its behavioral importance, and suggest disruptions in non-canonical Wnt genes such as PRICKLE2 may contribute to synaptic abnormalities underlying ASDs.


Assuntos
Transtornos Globais do Desenvolvimento Infantil/genética , Dendritos/ultraestrutura , Hipocampo/patologia , Hipocampo/fisiopatologia , Proteínas com Domínio LIM/deficiência , Proteínas com Domínio LIM/fisiologia , Proteínas de Membrana/deficiência , Proteínas de Membrana/fisiologia , Potenciais Pós-Sinápticos em Miniatura , Mutação de Sentido Incorreto , Neurônios/fisiologia , Mutação Puntual , Via de Sinalização Wnt , Sequência de Aminoácidos , Animais , Células Cultivadas , Transtornos Globais do Desenvolvimento Infantil/fisiopatologia , Transtornos Globais do Desenvolvimento Infantil/psicologia , Condicionamento Clássico , Comportamento Exploratório , Medo , Feminino , Reação de Congelamento Cataléptica/fisiologia , Humanos , Proteínas com Domínio LIM/genética , Masculino , Aprendizagem em Labirinto , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Potenciais Pós-Sinápticos em Miniatura/genética , Neurônios/patologia , Fenótipo , Densidade Pós-Sináptica/patologia , Proteínas Recombinantes de Fusão/metabolismo , Homologia de Sequência de Aminoácidos , Comportamento Social
10.
Sci Total Environ ; 447: 280-5, 2013 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-23410855

RESUMO

A comparative study of ultrasonication (US), Fenton's oxidation (FO) and ferro-sonication (FS) (combination of ultrasonication and Fenton's oxidation) advanced oxidation processes (AOPs) for degradation of carbamazepine (CBZ) from wastewater (WW) is reported for the first time. CBZ is a worldwide used antiepileptic drug, found as a persistent emerging contaminant in many wastewater treatment plants (WWTPs) effluents and other aquatic environments. The oxidation treatments of WW caused an effective removal of the drug. Among the various US, FO and FS pre-treatments carried out, higher soluble chemical oxygen demand (SCOD) and soluble organic carbon (SOC) increment (63 to 86% and 21 to 34%, respectively) was observed during FO pre-treatment process, resulting in higher removal of CBZ (84 to 100%) from WW. Furthermore, analysis of by-products formed during US, FO and FS pre-treatment in WW was carried out by using laser diode thermal desorption-atmospheric pressure chemical ionization (LDTD-APCI) coupled to tandem mass spectrometry (MS/MS). LDTD-APCI-MS/MS analysis indicated formation of two by-products, such as epoxycarbamazepine and hydroxycarbamazepine due to the reaction of hydroxyl radicals (OH) with CBZ during the three types of pre-treatment processes. In addition, the estrogenic activity of US, FO and FS pre-treated sample with CBZ and its by-products was carried out by Yeast Estrogen Screen (YES) assay method. Based upon the YES test results, none of the pre-treated samples showed estrogenic activity.


Assuntos
Carbamazepina/análise , Carbamazepina/química , Testes de Toxicidade/métodos , Águas Residuárias/toxicidade , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química , Análise da Demanda Biológica de Oxigênio , Carbamazepina/toxicidade , Estrogênios/toxicidade , Oxirredução , Quebeque , Sonicação , Espectrometria de Massas em Tandem , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Leveduras/efeitos dos fármacos
11.
Talanta ; 99: 247-55, 2012 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-22967548

RESUMO

In this study, the distribution of the anti-epileptic drug carbamazepine (CBZ) in wastewater (WW) and aqueous and solid phases of wastewater sludge (WWS) was carried out. A rapid and reliable method enabling high-throughput sample analysis for quicker data generation, detection, and monitoring of CBZ in WW and WWS was developed and validated. The ultrafast method (15s per sample) is based on the laser diode thermal desorption-atmospheric pressure chemical ionization (LDTD-APCI) coupled to tandem mass spectrometry (MS/MS). The optimization of instrumental parameters and method application for environmental analysis are presented. The performance of the novel method was evaluated by estimation of extraction recovery, linearity, precision and detection limit. The method detection limits was 12 ng L(-1) in WW and 3.4 ng g(-1) in WWS. The intra- and inter-day precisions were 8% and 11% in WW and 6% and 9% in WWS, respectively. Furthermore, three extraction methods, ultrasonic extraction (USE), microwave-assisted extraction (MAE) and accelerated solvent extraction (ASE) with three different solvent condition such as methanol, acetone and acetonitrile:ethyle acetate (5:1, v/v) were compared on the basis of procedural blank and method recovery. Overall, ASE showed the best extraction efficiency with methanol as compared to USE and MAE. Furthermore, the quantification of CBZ in WW and WWS samples showed the presence of contaminant in all stages of the treatment plant.


Assuntos
Pressão Atmosférica , Carbamazepina/análise , Cidades , Lasers , Esgotos/química , Temperatura , Poluentes Químicos da Água/análise , Carbamazepina/isolamento & purificação , Micro-Ondas , Reprodutibilidade dos Testes , Solventes/química , Espectrometria de Massas em Tandem , Fatores de Tempo , Ultrassom , Poluentes Químicos da Água/isolamento & purificação
12.
Environ Technol ; 33(10-12): 1445-53, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22856320

RESUMO

The performance of a laboratory-scale upflow anaerobic sludge blanket (UASB) reactor and a duckweed pond containing Lemna gibba was investigated for suitability for treating effluent for use in aquaculture. While treating low-strength sewage having a chemical oxygen demand (COD) of typically less than 200 mg/L, with an increase in hydraulic retention time (HRT) from 10.04 to 33.49 h, COD removal efficiency of the UASB reactor decreased owing to a decrease in organic loading rate (OLR) causing poor mixing in the reactor. However, even at the lower OLR (0.475 kg COD/(m3 x d)), the UASB reactor gave a removal efficiency of 68% for COD and 74% for biochemical oxygen demand (BOD). The maximum COD, BOD, ammonia-nitrogen and phosphate removal efficiencies of the duckweed pond were 40.77%, 38.01%, 61.87% and 88.57%, respectively. Decreasing the OLR by increasing the HRT resulted in an increase in efficiency of the duckweed pond for removal of ammonia-nitrogen and phosphate. The OLR of 0.005 kg COD/(m2 x d) and HRT of 108 h in the duckweed pond satisfied aquaculture quality requirements. A specific growth rate of 0.23% was observed for tilapia fish fed with duckweed harvested from the duckweed pond. The economic analysis proved that it was beneficial to use the integrated system of a UASB reactor and a duckweed pond for treatment of sewage.


Assuntos
Aquicultura , Reatores Biológicos , Magnoliopsida/metabolismo , Esgotos , Tilápia/crescimento & desenvolvimento , Animais , Aquicultura/economia , Biodegradação Ambiental , Biocombustíveis/análise , Biomassa , Estudos de Viabilidade , Metano/análise , Lagoas , Esgotos/análise , Água/análise
13.
Environ Technol ; 33(22-24): 2699-708, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23437671

RESUMO

Ozonation pre-treatment was investigated for the enhancement of sludge solids and organic matter solubilization and simultaneous degradation of bisphenol A (BPA), an endocrine disruptor compound from wastewater sludge (WWS). The ultrafast method (15 s per sample) used for the analysis of BPA in WWS is based on Laser Diode Thermal Desorption/Atmospheric Pressure Chemical Ionization coupled to tandem Mass Spectrometry. The statistical methods used for optimization studies comprised the response surface method with fractional factorial designs and central composite designs. The ozonation pre-treatment process was carried out with four independent variables, namely WWS solids concentration (15-35 g l(-1)), pH (5-7), ozone dose (5-25 mg g(-1) SS) and ozonation time (10-30 min). It was observed that among all the variables studied, ozone dose had more significantly (probability (p) < 0.001) affected the efficiency of the ozonation pre-treatment by increasing sludge solids (suspended solids (SS) and volatile solids) solubilization and organic matter (soluble chemical oxygen demand and soluble organic carbon) increment and BPA degradation from WWS. During the optimization process, it was found that higher BPA degradation (100%) could be obtained with 24 g l(-1) SS, 6.23 pH with an ozone dose of 26.14 mg g(-1) SS for 16.47 min ozonation time. The higher ozone dose used in this study was observed to be cost effective on the basis of solids and organic matter solubilization and degradation of BPA.


Assuntos
Compostos Benzidrílicos/química , Ozônio/química , Fenóis/química , Esgotos , Solubilidade , Espectrometria de Massas em Tandem
14.
Ultrason Sonochem ; 18(5): 1018-27, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21463964

RESUMO

Degradation of bisphenol A (BPA), an endocrine disruptor, from wastewater sludge (WWS) has attracted great interest recently. In the present study, the effects of different pre-treatment methods, including ultrasonication (US), Fenton's oxidation (FO) and ferro-sonication (FS) was assessed in terms of increase in solubilization of WWS and simultaneous degradation of BPA. Among US, FO and FS pre-treatment, higher suspended solids (SS), volatile suspended solids (VSS), chemical oxygen demand (COD) and soluble organic carbon (SOC) solubilization (39.7%, 51.2%, 64.5% and 17.6%, respectively) was observed during a ferro-sonication pre-treatment process carried out for 180 min, resulting in higher degradation of BPA (82.7%). In addition, the effect of rheological parameters (viscosity and particle size) and zeta potential on the degradation of BPA in raw and different pre-treated sludges were also investigated. The results showed that a decrease in viscosity and particle size and an increase in zeta potential resulted in higher degradation of BPA. BPA degradation by laccases produced by Sinorhizobium meliloti in raw and pre-treated sludge was also determined. Higher activity of laccases (207.9 U L(-1)) was observed in ferro-sonicated pre-treated sludge (180 min ultrasonic time), resulting in higher removal of BPA (0.083 µg g(-1)), suggesting concomitant biological degradation of BPA.


Assuntos
Fertilizantes/análise , Peróxido de Hidrogênio/química , Ferro/química , Fenóis/química , Fenóis/efeitos da radiação , Esgotos/química , Sonicação/métodos , Purificação da Água/métodos , Compostos Benzidrílicos , Peróxido de Hidrogênio/efeitos da radiação , Resíduos Industriais/prevenção & controle , Ferro/efeitos da radiação , Oxirredução/efeitos da radiação , Doses de Radiação , Poluentes Químicos da Água/química , Poluentes Químicos da Água/efeitos da radiação
15.
J Nanosci Nanotechnol ; 11(2): 899-918, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21456120

RESUMO

Renewed interest has arisen in the manufacture of nanoparticles due to their unusually enhanced physico-chemical properties and biological activities compared to the bulk parent materials. The industrial scale production and wide variety of application of nanoparticles has resulted in broad range applications in biotechnology, more recently in the increase in efficiency of biotransformation processes. Biotransformation processes utilized to form different bio-products and nanoparticles demonstrate various roles in the bio-products formation. In order to address the issue, it is necessary to understand the different methods available for synthesis of nanoparticles and their effects on biotransformation process, an efficient process for utilization of nanoparticles. In this review, an overview of physical, chemical and biological methods for synthesis of nanoparticles and their role in biotransformation process on formation of different bio-products, such as bioethanol, biohydrogen, biodiesel, enzymes and bioplastics is outlined. In fact, the nanoparticles are going to prove revolutionary in the field of biotransformation by improving the efficiency and yield and often widening the application range.


Assuntos
Biotransformação , Nanopartículas , Bactérias/metabolismo , Biodegradação Ambiental , Biocombustíveis , Enzimas/metabolismo , Fungos/metabolismo , Nanopartículas/química , Nanotecnologia , Plantas/metabolismo , Plásticos/metabolismo
16.
J Hazard Mater ; 189(1-2): 100-7, 2011 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-21354701

RESUMO

In this study, the application of response surface model in predicting and optimizing the ferro-sonication pre-treatment for degradation of bisphenol A (BPA), an endocrine disrupter compound from wastewater sludge (WWS) was investigated. The ferro-sonication pre-treatment process was carried out according to central composite design (CCD) with four independent variables such as wastewater sludge solids concentration, pH, ultrasonication time and FeSO(4) concentration. The effect of ferro-sonication pre-treatment was assessed in terms of increase in sludge solids (suspended solids (SS) and volatile solids (VS)) and organic matter (chemical oxygen demand (COD) and soluble organic carbon (SOC)) solubilization and simultaneous BPA degradation from WWS. It was observed that among all the variables studied, ultrasonication time had more significantly affected the efficiency of the ferro-sonication pre-treatment process followed by FeSO(4) and solids concentration. Through this optimization process, it was found that maximum BPA degradation of 88% could be obtained with 163 min ultrasonication time, 2.71 mg/L FeSO(4) concentration, pH 2.81 with 22 g/L SS. Further, the effect of ferro-sonication pre-treatment on biodegradation of WWS was also studied. It was observed that ultrasonication time had significant effect and the higher biodegradation (32.48%) was observed at 180 min ultrasonication time.


Assuntos
Biodegradação Ambiental , Fenóis/metabolismo , Esgotos/química , Sonicação , Poluentes Químicos da Água/metabolismo , Poluentes Ocupacionais do Ar , Compostos Benzidrílicos , Disruptores Endócrinos , Estrogênios não Esteroides , Sequestradores de Radicais Livres , Fenóis/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química
17.
Biotechnol Res Int ; 2011: 917505, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21350671

RESUMO

In vitro antibacterial activity of methanol, ethanol, and ethyl acetate extracts of raw and processed honey was tested against Gram-positive bacteria (Staphylococcus aureus, Bacillus subtilis, Bacillus cereus, Enterococcus faecalis, and Micrococcus luteus) and Gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa, and Salmonella typhi). Both types of honey showed antibacterial activity against tested organisms with the zone of inhibition (ZOI) ranging from 6.94 to 37.94 mm, while E. coli, S. typhi, and P. aeruginosa showed that sensibility towards all the extracts with ZOI ranges between 13.09 to 37.94 mm. The methanol extract showed more potent activity than other organic extracts. Gram-negative bacteria were found to be more susceptible as compared to Gram-positive bacteria except E. faecalis. The broth microdilution assay gave minimum inhibitory concentrations (MIC) value of 625 µg/mL, while the minimum bactericidal concentration (MBC) ranges between 625 µg/mL 2500 µg/mL. The study showed that honey has antibacterial activity (bacteriostatic and bactericidal effect), similar to antibiotics, against test organisms and provides alternative therapy against certain bacteria.

18.
Chemosphere ; 78(8): 923-41, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20083294

RESUMO

Bisphenol A (BPA), an endocrine disrupting compound largely used in plastic and paper industry, ends up in aquatic systems via wastewater treatment plants (WWTPs) among other sources. The identification and quantification of BPA in wastewater (WW) and wastewater sludge (WWS) is of major interest to assess the endocrine activity of treated effluent discharged into the environment. Many treatment technologies, including various pre-treatment methods, such as hydrolysis, Fenton oxidation, peroxidation, ultrasonication and ozonation have been developed in order to degrade BPA in WW and WWS and for the production of WWS based value-added products (VAPs). WWS based VAPs, such as biopesticides, bioherbicides, biofertilizers, bioplastics and enzymes are low cost biological alternatives that can compete with chemicals or other cost intensive biological products in the current markets. However, this field application is disputable due to the presence of these organic compounds which has been discussed with a perspective of simultaneous degradation. The pre-treatment produces an impact on rheology as well as value-addition which has been reviewed in this paper. Various analytical techniques available for the detection of BPA in WW and WWS are also discussed. Presence of heavy metals and possible thermodynamical behavior of the compound in WW and WWS can have major impact on BPA removal, which is also included in the review.


Assuntos
Biodegradação Ambiental , Disruptores Endócrinos , Fenóis , Esgotos/química , Eliminação de Resíduos Líquidos , Animais , Compostos Benzidrílicos , Fenômenos Químicos , Disruptores Endócrinos/análise , Disruptores Endócrinos/metabolismo , Humanos , Resíduos Industriais/legislação & jurisprudência , Fenóis/análise , Fenóis/metabolismo , Reologia , Termodinâmica , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água , Purificação da Água/métodos
19.
Biochem Soc Trans ; 35(Pt 5): 1064-8, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17956280

RESUMO

Voltage-gated K(+) channels are key regulators of neuronal excitability. The Kv2.1 voltage-gated K(+) channel is the major delayed rectifier K(+) channel expressed in most central neurons, where it exists as a highly phosphorylated protein. Kv2.1 plays a critical role in homoeostatic regulation of intrinsic neuronal excitability through its activity- and calcineurin-dependent dephosphorylation. Here, we review studies leading to the identification and functional characterization of in vivo Kv2.1 phosphorylation sites, a subset of which contribute to graded modulation of voltage-dependent gating. These findings show that distinct developmental-, cell- and state-specific regulation of phosphorylation at specific sites confers a diversity of functions on Kv2.1 that is critical to its role as a regulator of intrinsic neuronal excitability.


Assuntos
Ativação do Canal Iônico , Canais de Potássio Shab/fisiologia , Linhagem Celular , Humanos , Neurônios/fisiologia , Fosforilação , Canais de Potássio Shab/química , Canais de Potássio Shab/metabolismo , Espectrometria de Massas em Tandem
20.
J Commun Dis ; 32(4): 289-94, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11668940

RESUMO

Leishmania donovani causes visceral leishmaniasis claiming several thousand lives every year in Indian sub-continent. The etiological agent is grown in cell free media supplemented with fetal calf serum (FCS). Urine from human beings and other mammalian species has also been reported to stimulate growth of Leishmania species No study has been carried out Leishmania donovani. Therefore, we studied the feasibility of culturing Leishmania donovani promastigotes in M199 medium supplemented with 10% human urine and compared the phenotypic and genotypic characters under supplementation with urine vis-a-vis FCS. The growth curve showed no significant difference in the promastigote counts in urine vs. FCS supplementation. The best growth was observed in cultures supplemented with the post-menopausal urine. No difference in antigenic bands and RFLP pattern was seen indicating that no alteration occurred in strain specific characters of the parasites cultured with human urine.


Assuntos
Leishmania donovani/crescimento & desenvolvimento , Leishmaniose Visceral/parasitologia , Urina , Animais , Meios de Cultura Livres de Soro , Humanos
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