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1.
Cureus ; 15(11): e49145, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38130538

RESUMO

Introduction Preeclampsia is a multisystem disorder with hypertension after 20 weeks of gestation. Among many predictors of preeclampsia, vitamin D being one of them is under many studies for establishing a correlation between levels of vitamin D and preeclampsia. Objective To observe a relation between vitamin D levels and preeclampsia and assess related fetomaternal outcomes. Method It is an observational study at the tertiary care center. One hundred twenty patients, out of which 60 were taken as cases with BP>140/90, and 60 were taken as controls with normal BP in a tertiary care center from January 1, 2020, to June 30, 2021. All investigations were sent, and the mode of delivery and the fetomaternal outcome were assessed. Results Compared to normal pregnant patients, preeclamptic patients have significantly lower levels of vitamin D with a p-value of <0.001, which is significant. Conclusion There is a relationship between vitamin D levels and preeclampsia. However, the effects of supplementation of vitamin D on fetomaternal outcomes need further studies.

2.
Phys Chem Chem Phys ; 25(18): 12900-12913, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37165884

RESUMO

Polyethoxylated surfactants, such as those of the Tween and Pluronic series, are commonly used to disperse carbon nanotubes (CNTs) and other nanoparticles. However, the current understanding of the nature of interactions between these surfactants and CNTs is limited. The nature of the interactions between surfactants (Tween-80 [T80] and Pluronic F68 [PF68]) and CNTs was investigated using high-resolution magic angle spinning nuclear magnetic resonance (HRMAS-NMR) and coarse-grained molecular dynamics (MD) simulations. HRMAS-NMR revealed that T80 molecules interact with single-walled CNTs (SWCNTs) and multi-walled CNTs (MWCNTs) via the oleyl chain, whereas PF68 molecules interact with the surface of SWCNTs and MWCNTs via the polypropylene oxide residues. The polyethylene oxide chains were oriented towards the external aqueous environment. The HRMAS-NMR results were supported by MD simulations, and the latter provided further insights into the nature of the interactions.

3.
Protein Sci ; 30(7): 1454-1466, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34018649

RESUMO

Fusion transcription factors generated by genomic translocations are common drivers of several types of cancers including sarcomas and leukemias. Oncofusions of the FET (FUS, EWSR1, and TAF15) family proteins result from the fusion of the prion-like domain (PLD) of FET proteins to the DNA-binding domain (DBD) of certain transcription regulators and are implicated in aberrant transcriptional programs through interactions with chromatin remodelers. Here, we show that FUS-DDIT3, a FET oncofusion protein, undergoes PLD-mediated phase separation into liquid-like condensates. Nuclear FUS-DDIT3 condensates can recruit essential components of the global transcriptional machinery such as the chromatin remodeler SWI/SNF. The recruitment of mammalian SWI/SNF (mSWI/SNF) is driven by heterotypic PLD-PLD interactions between FUS-DDIT3 and core subunits of SWI/SNF, such as the catalytic component BRG1. Further experiments with single-molecule correlative force-fluorescence microscopy support a model wherein the fusion protein forms condensates on DNA surface and enrich BRG1 to activate transcription by ectopic chromatin remodeling. Similar PLD-driven co-condensation of mSWI/SNF with transcription factors can be employed by other oncogenic fusion proteins with a generic PLD-DBD domain architecture for global transcriptional reprogramming.


Assuntos
Proteínas Cromossômicas não Histona/metabolismo , Proteínas de Fusão Oncogênica/metabolismo , Príons/metabolismo , Proteína FUS de Ligação a RNA/metabolismo , Fatores de Transcrição/metabolismo , Linhagem Celular , Proteínas Cromossômicas não Histona/química , Proteínas Cromossômicas não Histona/genética , Humanos , Microscopia de Fluorescência , Proteínas de Fusão Oncogênica/química , Proteínas de Fusão Oncogênica/genética , Príons/química , Príons/genética , Domínios Proteicos , Proteína FUS de Ligação a RNA/química , Proteína FUS de Ligação a RNA/genética , Fatores de Transcrição/química , Fatores de Transcrição/genética
4.
Nat Commun ; 12(1): 872, 2021 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-33558506

RESUMO

Multivalent protein-protein and protein-RNA interactions are the drivers of biological phase separation. Biomolecular condensates typically contain a dense network of multiple proteins and RNAs, and their competing molecular interactions play key roles in regulating the condensate composition and structure. Employing a ternary system comprising of a prion-like polypeptide (PLP), arginine-rich polypeptide (RRP), and RNA, we show that competition between the PLP and RNA for a single shared partner, the RRP, leads to RNA-induced demixing of PLP-RRP condensates into stable coexisting phases-homotypic PLP condensates and heterotypic RRP-RNA condensates. The morphology of these biphasic condensates (non-engulfing/ partial engulfing/ complete engulfing) is determined by the RNA-to-RRP stoichiometry and the hierarchy of intermolecular interactions, providing a glimpse of the broad range of multiphasic patterns that are accessible to these condensates. Our findings provide a minimal set of physical rules that govern the composition and spatial organization of multicomponent and multiphasic biomolecular condensates.


Assuntos
Proteínas de Ligação a RNA/metabolismo , RNA/metabolismo , Sequência de Aminoácidos , Arginina/metabolismo , Sequência de Bases , Peptídeos/metabolismo , Príons/metabolismo , Proteínas de Ligação a RNA/química , Tensão Superficial
5.
Methods Enzymol ; 646: 143-183, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33453924

RESUMO

Biomolecular condensates are membrane-less sub-cellular compartments that perform a plethora of important functions in signaling and storage. The material properties of biomolecular condensates such as viscosity, surface tension, viscoelasticity, and macromolecular diffusion play important roles in regulating their biological functions. Aberrations in these properties have been implicated in various neurodegenerative disorders and certain types of cancer. Unraveling the molecular driving forces that control the fluid structure and dynamics of biomolecular condensates across different length- and time-scales necessitates the application of innovative biophysical methodologies. In this chapter, we discuss major experimental techniques that are widely used to study the material states and dynamics of biomolecular condensates as well as their practical and conceptual limitations. We end this chapter with a discussion on more advanced tools that are currently emerging to address the complex fluid dynamics of these condensates.


Assuntos
Substâncias Macromoleculares , Difusão , Viscosidade
6.
Mol Pharm ; 18(1): 124-147, 2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-33346663

RESUMO

The rate and extent of drug release under physiological conditions is a key factor influencing the therapeutic activity of a formulation. Real-time detection of drug release by conventional pharmacokinetics approaches is confounded by low sensitivity, particularly in the case of tissue-targeted novel drug delivery systems, where low concentrations of the drug reach systemic circulation. We present a novel fluorescence turn-on platform for real-time monitoring of drug release from nanoparticles based on reversible fluorescence quenching in fluorescein esters. Fluorescein-conjugated carbon nanotubes (CNTs) were esterified with methotrexate in solution and solid phase, followed by supramolecular functionalization with a chemoenhancer (suramin) or/and a stealth agent (dextran sulfate). Suramin was found to increase the cytotoxicity of methotrexate in A549 cells. On the other hand, dextran sulfate exhibited no effect on cytotoxicity or cellular uptake of CNTs by A549 cells, while a decrease in cellular uptake of CNTs and cytotoxicity of methotrexate was observed in macrophages (RAW 264.7 cells). Similar results were also obtained when CNTs were replaced with graphene. Docking studies revealed that the conjugates are not internalized by folate receptors/transporters. Further, docking and molecular dynamics studies revealed the conjugates do not exhibit affinity toward the methotrexate target, dihydrofolate reductase. Molecular dynamics studies also revealed that distinct features of dextran-CNT and suramin-CNT interactions, characterized by π-π interactions between CNTs and dextran/suramin. Our study provides a simple, cost-effective, and scalable method for the synthesis of nanoparticles conferred with the ability to monitor drug release in real-time. This method could also be extended to other drugs and other types of nanoparticles.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Nanopartículas/química , Nanotubos de Carbono/química , Neoplasias/tratamento farmacológico , Células A549 , Animais , Linhagem Celular , Linhagem Celular Tumoral , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Fluorescência , Grafite/química , Humanos , Metotrexato/química , Metotrexato/farmacologia , Camundongos , Células RAW 264.7
7.
J Am Chem Soc ; 141(37): 14593-14602, 2019 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-31437398

RESUMO

In eukaryotic cells, ribonucleoproteins (RNPs) form mesoscale condensates by liquid-liquid phase separation that play essential roles in subcellular dynamic compartmentalization. The formation and dissolution of many RNP condensates are finely dependent on the RNA-to-RNP ratio, giving rise to a windowlike phase separation behavior. This is commonly referred to as reentrant liquid condensation (RLC). Here, using ribonucleoprotein-inspired polypeptides with low-complexity RNA-binding sequences as well as an archetypal disordered RNP, fused in sarcoma, as model systems, we investigate the molecular driving forces underlying this nonmonotonous phase transition. We show that an interplay between short-range cation-π attractions and long-range electrostatic forces governs the heterotypic RLC behavior of RNP-RNA complexes. Short-range attractions, which can be encoded by both polypeptide chain primary sequence and nucleic acid base sequence, control the two-phase coexistence regime, regulate material properties of polypeptide-RNA condensates, and oppose condensate reentrant dissolution. In the presence of excess RNA, a competition between short-range attraction and long-range electrostatic repulsion drives the formation of a colloidlike cluster phase. With increasing short-range attraction, the fluid dynamics of the cluster phase is arrested, leading to the formation of a colloidal gel. Our results reveal that phase behavior, supramolecular organization, and material states of RNP-RNA assemblies are controlled by a dynamic interplay between molecular interactions at different length scales.


Assuntos
RNA/química , Ribonucleoproteínas/química , Arginina/análise , Lisina/análise , Transição de Fase , Eletricidade Estática
8.
J Contemp Dent Pract ; 20(6): 707-715, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31358714

RESUMO

AIM: The purpose of this research is to compare peri-implant bone level in immediate and conventionally loaded implants using flap and flapless techniques. MATERIALS AND METHODS: Forty patients were selected and were subjected into four groups. Group A: 10 patients with immediate loading (IL) by raising the flap. Group B: 10 patients with IL without raising the flap. Group C: 10 patients with conventional loading by raising the flap. Group D: 10 patients with conventional loading without raising the flap. RESULTS: It was observed that for most of the flapless techniques with IL cases, the bone loss settled at first thread or just below the implant collar after 6 months. CONCLUSION: It was seen that the crestal bone height was reduced in both flap and flapless techniques by immediate and conventional loading, respectively. On comparing the bone loss, the flapless approach by IL showed statistically significant lesser reduction as determined by radiovisiography. CLINICAL SIGNIFICANCE: Postoperative pain was less in the flapless technique as compared to the traditional flap technique. IL minimizes invasiveness, complexity, and also improves acceptance by patients.


Assuntos
Implantação Dentária Endóssea , Implantes Dentários , Humanos , Retalhos Cirúrgicos
9.
Biomolecules ; 9(2)2019 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-30791483

RESUMO

Ribonucleoprotein (RNP) granules are membraneless liquid condensates that dynamically form,dissolve, and mature into a gel-like state in response to a changing cellular environment. RNP condensation islargely governed by promiscuous attractive inter-chain interactions mediated by low-complexity domains(LCDs). Using an archetypal disordered RNP, fused in sarcoma (FUS), here we study how molecular crowdingimpacts the RNP liquid condensation. We observe that the liquid⁻liquid coexistence boundary of FUS islowered by polymer crowders, consistent with an excluded volume model. With increasing bulk crowderconcentration, the RNP partition increases and the diffusion rate decreases in the condensed phase.Furthermore, we show that RNP condensates undergo substantial hardening wherein protein-dense dropletstransition from viscous fluid to viscoelastic gel-like states in a crowder concentration-dependent manner.Utilizing two distinct LCDs that broadly represent commonly occurring sequence motifs driving RNP phasetransitions, we reveal that the impact of crowding is largely independent of LCD charge and sequence patterns.These results are consistent with a thermodynamic model of crowder-mediated depletion interaction, whichsuggests that inter-RNP attraction is enhanced by molecular crowding. The depletion force is likely to play akey role in tuning the physical properties of RNP condensates within the crowded cellular space.


Assuntos
Ribonucleoproteínas/química , Sarcoma/química , Humanos , Substâncias Macromoleculares/química , Tamanho da Partícula , Propriedades de Superfície , Termodinâmica
10.
BMC Nephrol ; 20(1): 24, 2019 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-30674290

RESUMO

BACKGROUND: Reproductive function in women with end stage renal disease generally improves after kidney transplant. However, pregnancy remains challenging due to the risk of adverse clinical outcomes. METHODS: We searched PubMed/MEDLINE, Elsevier EMBASE, Scopus, BIOSIS Previews, ISI Science Citation Index Expanded, and the Cochrane Central Register of Controlled Trials from date of inception through August 2017 for studies reporting pregnancy with kidney transplant. RESULTS: Of 1343 unique studies, 87 met inclusion criteria, representing 6712 pregnancies in 4174 kidney transplant recipients. Mean maternal age was 29.6 ± 2.4 years. The live-birth rate was 72.9% (95% CI, 70.0-75.6). The rate of other pregnancy outcomes was as follows: induced abortions (12.4%; 95% CI, 10.4-14.7), miscarriages (15.4%; 95% CI, 13.8-17.2), stillbirths (5.1%; 95% CI, 4.0-6.5), ectopic pregnancies (2.4%; 95% CI, 1.5-3.7), preeclampsia (21.5%; 95% CI, 18.5-24.9), gestational diabetes (5.7%; 95% CI, 3.7-8.9), pregnancy induced hypertension (24.1%; 95% CI, 18.1-31.5), cesarean section (62.6, 95% CI 57.6-67.3), and preterm delivery was 43.1% (95% CI, 38.7-47.6). Mean gestational age was 34.9 weeks, and mean birth weight was 2470 g. The 2-3-year interval following kidney transplant had higher neonatal mortality, and lower rates of live births as compared to > 3 year, and < 2-year interval. The rate of spontaneous abortion was higher in women with mean maternal age < 25 years and > 35 years as compared to women aged 25-34 years. CONCLUSION: Although the outcome of live births is favorable, the risks of maternal and fetal complications are high in kidney transplant recipients and should be considered in patient counseling and clinical decision making.


Assuntos
Transplante de Rim , Resultado da Gravidez , Gravidez de Alto Risco , Aborto Induzido/estatística & dados numéricos , Aborto Espontâneo/epidemiologia , Adulto , Peso ao Nascer , Cesárea/estatística & dados numéricos , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Complicações Pós-Operatórias/epidemiologia , Gravidez , Complicações na Gravidez/epidemiologia , Utilização de Procedimentos e Técnicas , Natimorto/epidemiologia , Adulto Jovem
11.
Cleve Clin J Med ; 85(8): 629-638, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30102593

RESUMO

In caring for patients with chronic kidney disease, it is important to prevent and treat hyperphosphatemia with a combination of dietary restrictions and phosphorus binders. This review describes the pathophysiology and control of hyperphosphatemia and the different classes of phosphorus binders with respect to their availability, cost, side effects, and scenarios in which one class of binder may be more beneficial than another.


Assuntos
Quelantes/uso terapêutico , Hiperfosfatemia/fisiopatologia , Fósforo/sangue , Insuficiência Renal Crônica/sangue , Humanos , Hiperfosfatemia/etiologia , Diálise Renal/efeitos adversos , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/terapia
12.
J Water Health ; 15(1): 103-111, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28151444

RESUMO

A novel, phosphate-binding exobiopolymer (EBP) produced by Acinetobacter haemolyticus MG606 was characterized and its biocompatibility evaluated in RAW 264.7 cells and in mice. EBP was identified as a 50 kDa heteropolysaccharide composed of pentose and hexose sugars. EBP exhibited cytotoxicity, stimulation of free radical production and loss of mitochondrial and lysosomal integrity in RAW 264.7 cells at 500 µg/mL concentration while lower concentrations exhibited no significant (p > 0.05) effect on these parameters. EBP exhibited dose-dependent mortality, body weight reduction, hypothermia and clinical signs of toxicity in mice following intraperitoneal administration. The LD50 of EBP was determined to be 92.31 mg/kg. Overall, the results of our study suggest that composition of EBP produced by A. haemolyticus MG606 is distinct from EBP produced by other Acinetobacter spp. The high biocompatibility supports application of EBP as a safe biosorbent for phosphate remediation.


Assuntos
Acinetobacter/química , Biopolímeros/toxicidade , Acinetobacter/metabolismo , Animais , Biopolímeros/análise , Feminino , Injeções Intraperitoneais , Camundongos , Fosfatos/metabolismo , Células RAW 264.7 , Testes de Toxicidade
13.
Int J Biol Macromol ; 94(Pt A): 187-193, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27720965

RESUMO

This study evaluated five extracellular polymers of bacterial origin possessing mucoadhesive properties for their antimicrobial properties and toxicological characteristics. Of the five tested mucoadhesive biopolymers, the extracellular polymer produced by a strain of Acinetobacter haemolyticus exhibited broad antimicrobial efficacy towards Yersinia enterocolitica, Salmonella typhimurium, Listeria monocytogenes, Escherichia coli O157:H7 and Bacillus subtilis. Significant (p<0.05) inhibition of gram negative bacterial pathogens followed by gram positives were observed with the biopolymer at a dose of 40-60µg ml-1 at ambient temperature. The cytotoxicity under in vitro conditions and oral toxicity in murine models was also evaluated. The biopolymer did not elicit either haemolytic activity or toxicity in RAW 264.7 cell lines. Haemotological, histopathological and general examinations indicated no adverse effects in Swiss albino mice fed with the biopolymer (120mg kg-1 body weight-1 day1) over a period of 30 days. These results suggested that the biopolymer was well tolerated without any signs of toxicity and may have several potential biomedical applications where disinfection is desired.


Assuntos
Acinetobacter/química , Antibacterianos/farmacologia , Polissacarídeos Bacterianos/farmacologia , Administração Oral , Animais , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antibiose , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Avaliação Pré-Clínica de Medicamentos , Concentração Inibidora 50 , Masculino , Camundongos , Polissacarídeos Bacterianos/química , Polissacarídeos Bacterianos/isolamento & purificação , Células RAW 264.7
14.
J Phys Ther Sci ; 28(1): 293-7, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26957777

RESUMO

[Purpose] Lack of physical activity and an uncontrolled diet cause excessive weight gain, which leads to obesity and other metabolic disorders. Studies have indicated that brisk walking and aerobics are the best methods for controlling and reducing weight and body mass composition. [Subjects and Methods] In this study, 45 overweight women were enrolled and divided into 3 groups. Women not involved in brisk walking or aerobics were included in group A (n = 15) as control subjects; women involved in brisk walking were in group B (n = 15); and those involved in aerobics were in group C (n = 15). [Results] This program was carried out 5 days/week for 10 weeks. Pre- and post-measurements of body mass index, waist and hip circumference, and skinfold thickness of the abdomen, subscapular area, biceps, and triceps were recorded for the women in all 3 groups. All values decreased in women who participated in brisk walking and aerobics for 10 weeks. [Conclusion] These results indicate that aerobics with diet therapy is a more effective intervention program for controlling and reducing body mass index and skinfold thickness than brisk walking with diet therapy in North Indian women.

15.
Microbiol Res ; 181: 8-14, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26640047

RESUMO

Several members of the Acinetobacter spp. produce exobiopolymer (EBP) of considerable biotechnological interest. In a previous study, we reported phosphate removal capacity of EBP produced by Acinetobacter haemolyticus. Insertional mutagenesis was attempted to develop EBP-overproducing strains of A. haemolyticus and mutant MG606 was isolated. In order to understand the underlying mechanism of overproduction, the EBP overproducing mutant MG606 was analyzed and compared with the wild type counterpart for its key EBP synthetic enzymes. The EBP produced by MG606 mutant was 650 mg/L compared to 220 mg/L in its wild type counterpart. Significantly high (p<0.05) levels of phosphoglucomutase/phosphomannomutase (PGM/PMM) in MG606 mutant was noted, whereas activities of other enzymes responsible for EBP synthesis showed no significant change (p>0.05). The up-regulation of PGM/PMM expression in mutant was further confirmed by real time reverse transcriptase (RT)-PCR of PGM/PMM transcripts. The optimal conditions for PGM/PMM activity were found to be 35 °C and pH 7.5; PGM/PMM activity was inhibited by ions such as lithium, zinc, nickel. Further, incubation of cells with a PGM inhibitor (lithium) resulted in a concentration-dependent decrease in EBP production further confirming the role of PGM/PMM overexpression in enhanced EBP production by the mutant. Overall the results of our study indicate a key role of PGM/PMM in enhanced EBP production, as evident from enhanced enzyme activity, increased PGM/PMM transcripts and reduction in EBP synthesis by a PGM inhibitor. We envisage a potential exploitation of the insights so obtained to effectively engineer strains of Acinetobacter for overproducing phosphate binding EBP.


Assuntos
Acinetobacter/enzimologia , Fosfoglucomutase/metabolismo , Fosfotransferases (Fosfomutases)/metabolismo , Regulação para Cima , Acinetobacter/efeitos dos fármacos , Acinetobacter/genética , Eletroforese em Gel de Poliacrilamida , Mutagênese Insercional , Fosfoglucomutase/química , Fosfoglucomutase/genética , Fosfotransferases (Fosfomutases)/química , Fosfotransferases (Fosfomutases)/genética , DNA Polimerase Dirigida por RNA , Reação em Cadeia da Polimerase em Tempo Real , Especificidade por Substrato , Ativação Transcricional
16.
Carbohydr Polym ; 132: 72-9, 2015 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-26256326

RESUMO

The present study evaluated an extracellular, novel biopolymer produced by Acinetobacter haemolyticus MG606 for its physicochemical properties and phosphate binding mechanism. The exobiopolymer (EBP) was characterized to be majorly polysaccharide in nature consisting of 48.9 kDa heteropolysaccharide composed of galactose, glucose, xylose, lyxose, allose, ribose, arabinose, mannose and fructose. Maximum phosphate binding efficiency of 25mg phosphate/g of EBP was described by Langmuir isotherm and further, the physicochemical and spectroscopic studies revealed that phosphate appeared to bind predominantly with the polysaccharide fraction, and to a relatively lesser extent to protein fraction of EBP. The electrostatic interactions with amino groups and ligand exchange with hydroxyl groups of EBP were found to be primary basis for phosphate binding mechanism. The results of this study implicate the feasibility of the EBP for commercial bioremediation processes.


Assuntos
Acinetobacter/metabolismo , Poluentes Ambientais/isolamento & purificação , Fosfatos/isolamento & purificação , Polissacarídeos/metabolismo , Acinetobacter/química , Biodegradação Ambiental , Poluentes Ambientais/metabolismo , Fosfatos/metabolismo , Polissacarídeos/química
17.
Water Sci Technol ; 68(12): 2619-25, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24355849

RESUMO

The present study was conducted to develop a biosensor by exploiting phosphate-binding capacity of exobiopolymer (EBP) produced by Acinetobacter sp. An environmental isolate of EBP-producing Acinetobacter sp. was subjected to transposon (Tn5) mutagenesis to overproduce EBP and afford improved phosphate selectivity. A mutant producing the highest amount of EBP with high phosphate-binding capacity was selected for biosensor probe fabrication. Phosphate samples were filtered through EBP-coated membranes and phosphate retained on membranes was determined by molybdenum blue method. The color produced was read using a LED 690 nm/photodiode detection system linked to an amplifier and signals were converted to appropriate phosphate concentrations. The biosensor had a limit of detection of 0.5 mg/L and a limit of quantification 1 mg/L. The biosensor as well as the probe were found to be stable for at least 28 days. In conclusion, we believe that the biosensor may have applications in monitoring of wastewater and environmental samples. Further, the enrichment of phosphate levels by EBP can help in analysis of very low phosphate concentrations.


Assuntos
Biopolímeros/química , Técnicas Biossensoriais/instrumentação , Monitoramento Ambiental/instrumentação , Fosfatos/análise , Poluentes Químicos da Água/análise , Acinetobacter/genética , Acinetobacter/crescimento & desenvolvimento , Biopolímeros/isolamento & purificação , Técnicas Biossensoriais/métodos , Monitoramento Ambiental/métodos , Desenho de Equipamento , Reprodutibilidade dos Testes , Águas Residuárias/química
18.
Indian J Physiol Pharmacol ; 50(3): 303-8, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17193904

RESUMO

We introduce a pragmatic approach towards the corrected Base Excess (BE) by including the large variability of the apparent dissociation constant pK' in non-logarithmic form in Henderson-Hasselbach bicarbonate ion equilibria thereby resulting in a significant correction both in calculated bicarbonate ion concentration and BE at 37 degrees C.


Assuntos
Equilíbrio Ácido-Base , Bicarbonatos/análise , Animais , Gasometria/métodos , Humanos , Reprodutibilidade dos Testes
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