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1.
Sci Rep ; 14(1): 1131, 2024 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-38212429

RESUMO

The main objective of this study was to investigate the potential probiotic properties of Lacticaseibacillus rhamnosus VHProbi®M15 (M15). This study examined the effects of M15 on sucralfate-induced constipation in a mouse model. The BALB/c mice were randomly divided into four groups: the normal group (NOR) was without any treatment, while the constipation (CON), phenolphthalein (PHE), and probiotic (PRO) treatment groups were fed with sucralfate until the appearance of constipation symptoms. Afterward, the NOR and CON groups were given 1 ml saline orally every day until the end of the experiment; the PHE and PRO groups were given phenolphthalein or M15 suspension in 1 ml orally, respectively. Compared with the CON group, the fecal water content and intestinal peristalsis improved in the PRO group. Here, intake of M15 effectively attenuated sucralfate-induced constipation, recuperated colonic epithelial integrity, and increased serum levels of gastrointestinal excitatory neurotransmitters (motilin, gastrin, substance P). Analysis of the intestinal microbiota of mice by 16S rRNA metagenomic revealed an increase in the relative abundance of Bacteroides and a decrease in Sclerotinia, Verrucosa and Proteus in the PRO group. Compared with the CON group, the constipation-induced intestinal microecological changes were partially recovered in the PHE and PRO groups. These results demonstrate that M15 enhanced gastrointestinal transit and alleviated in mice with sucralfate-induced constipation.


Assuntos
Galanina/análogos & derivados , Lacticaseibacillus rhamnosus , Probióticos , Substância P/análogos & derivados , Camundongos , Animais , Sucralfato/efeitos adversos , RNA Ribossômico 16S , Constipação Intestinal/induzido quimicamente , Constipação Intestinal/tratamento farmacológico , Probióticos/farmacologia , Probióticos/uso terapêutico , Fenolftaleínas/efeitos adversos
2.
JPEN J Parenter Enteral Nutr ; 47(7): 904-910, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37350060

RESUMO

BACKGROUND: Our goal was to quantify the pH and total acidity of human milk fortified with human milk fortifiers (HMFs), powder infant formulas, and protein additives. METHODS: Commercial liquid HMFs and powder infant formulas were added to pasteurized pooled donor human milk in triplicate and stirred. The pH of unfortified and fortified human milk at 22, 24, 26, 27, 28, and 30 kcal/ounce (624, 680, 737, 765, 794, and 850 kcal/g, respectively) was determined using a pH meter. Phenolphthalein acidity at 24 and 30 kcal/ounce (680 and 850 kcal/g, respectively) was determined using diluted sodium hydroxide. RESULTS: The pH of unfortified human milk increased within the first hour (6.52 ± 0.06 vs 6.62 ± 0.05, P < 0.0001). Changes in pH largely correlated with caloric density; however, directional changes varied considerably between HMFs and powder infant formulas. Two liquid HMFs demonstrated modest reductions in pH with increasing caloric density whereas one liquid HMF alkalinized human milk with increasing caloric density (analysis of variance P < 0.0001). Phenolphthalein acidity was significantly higher for five HMFs and lower for one HMF at 30 kcal/ounce (850 kcal/g) but not 24 kcal/ounce (680 kcal/g). Powder infant formulas generally increased pH with increasing caloric density (analysis of variance P < 0.0001), but no differences in phenolphthalein acidity were noted. CONCLUSION: Changes in acid/base balancefor fortified human milk are variable and may be a consideration when selecting a fortifying agent for human milk.


Assuntos
Alimentos Fortificados , Leite Humano , Lactente , Humanos , Pós , Suplementos Nutricionais , Fenolftaleínas
3.
Biosensors (Basel) ; 13(5)2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37232895

RESUMO

Osteoarthritis (OA) is the most common joint disease, which accompanies pain and inconvenience in daily life owing to degradation of cartilage and adjacent tissues. In this study, we propose a simple point-of-care testing (POCT) kit for the detection of the MTF1 OA biomarker to achieve on-site clinical diagnosis of OA. The kit contains an FTA card for patient sample treatments, a sample tube for loop-mediated isothermal amplification (LAMP), and a phenolphthalein-soaked swab for naked eye detection. The MTF1 gene was isolated from synovial fluids using an FTA card and amplified using the LAMP method at 65 °C for 35 min. A test part of the phenolphthalein-soaked swab was decolorized in the presence of the MTF1 gene due to the pH change after the LAMP, but the color remained pink in the absence of the MTF1 gene. The control part of the swab served as a reference color in relation to the test part. When real-time LAMP (RT-LAMP), gel electrophoresis, and colorimetric detection of the MTF1 gene were performed, the limit of detection (LOD) was confirmed at 10 fg/µL, and the overall processes were completed in 1 h. The detection of an OA biomarker in the form of POCT was reported for the first time in this study. The introduced method is expected to serve as a POCT platform directly applicable by clinicians for easy and rapid identification of OA.


Assuntos
Osteoartrite , Testes Imediatos , Humanos , Técnicas de Diagnóstico Molecular , Limite de Detecção , Técnicas de Amplificação de Ácido Nucleico/métodos , Osteoartrite/diagnóstico , Biomarcadores , Fenolftaleínas , Sensibilidade e Especificidade
4.
Pharm Biol ; 61(1): 125-134, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36582187

RESUMO

CONTEXT: Bombax ceiba Linnaeus (Bombacaceae) is known as silk cotton tree, the flowers of which are used in many medicinal applications. OBJECTIVE: To investigate the therapeutic effect of B. ceiba flower aqueous extracts (BCE) against loperamide-induced constipation and characterize the chemical composition of BCE. MATERIALS AND METHODS: Sixty male Kunming mice were divided into control (saline), model (10 mg/kg loperamide + saline), phenolphthalein (10 mg/kg loperamide + 10 mg/kg phenolphthalein) and different dosage of BCE (10 mg/kg loperamide + 40, 80 and 160 mg/kg BCE, respectively) groups, and received intragastric administrations for eight days. Faecal water content, number of faeces, first black-stool defecation time and gastrointestinal transit rates were evaluated. Various biochemical and molecular biomarkers were assessed in blood and colon. UPLC-ESI-QTOF-MS/MS was used to tentatively identify the composition of the BCE. RESULTS: BCE treatment (160 mg/kg) could increase faecal water (15.75%), faeces number (11.65%), gastrointestinal transit rate (25.37%) and decrease first black-stool defecation time (24.04%). The BCE (80 mg/kg) increased the serum level of motilin (30.62%), gastrin (54.46%) and substance P (18.99%), and decreased somatostatin (19.47%). Additionally, the BCE (160 mg/kg) reduced the mucosal damage, restored colonic goblet cell function, down-regulated the protein expression of AQP3 (33.60%) and increased c-kit protein expression (11.63%). Twelve known compounds, including protocatechuic acid, chlorogenic acid and rutin, previously reported in B. ceiba, were identified in the BCE. DISCUSSION AND CONCLUSIONS: This study suggested that BCE is a promising agent for the treatment of constipation.


Assuntos
Bombax , Loperamida , Camundongos , Animais , Loperamida/toxicidade , Bombax/química , Espectrometria de Massas em Tandem , Constipação Intestinal/induzido quimicamente , Constipação Intestinal/tratamento farmacológico , Flores , Água , Fenolftaleínas/efeitos adversos
5.
Sensors (Basel) ; 22(19)2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-36236640

RESUMO

In this work, a coulometer was developed from a digitally controlled galvanostat. A simple colorimeter based on a RGB LED was used as a light emitter coupled to light detectors, while light dependent resistance (LDR) and photodiodes have been developed as endpoint detectors. Both hardware and software have been adapted from the original galvanostat design. Regarding the hardware, new electrical signal conditioners (filters and voltage dividers) were included to optimize the working system. The software was developed based on an open source Arduino UNO microcontroller. The different variables that control the titration process are managed by an add-in module for Excel data acquisition software that is freely available. A study of the possible variables that influence the titration process has been carried out. The system was tested with two classical coulometric titrations such as iodometry (thiosulfate, ascorbic acid) and acid/base (potassium acid phthalate as standard). The developed system is versatile as different endpoint color indicators can be employed (starch and phenolphthalein for the investigated reactions). Different experimental arrangements have been studied: the nature of the electrodes (Pt, Ag), type of cells (two separate compartments or a single compartment), and light detectors (LDR, photodiode). The influence of several experimental parameters (both electrical, light, and integration time) was studied and chosen to obtain the best performance of the complete system. Reproducibility results below 1% can be obtained under controlled conditions. In the case of acid/base titrations, the presence of atmospheric carbon dioxide was detected, whose interference was mainly affected by the stirring rate and the titration time.


Assuntos
Dióxido de Carbono , Tiossulfatos , Ácido Ascórbico , Fenolftaleínas , Potássio , Reprodutibilidade dos Testes , Amido
6.
Langmuir ; 38(38): 11743-11752, 2022 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-36109337

RESUMO

Liquid marbles (LMs), droplets encapsulated with micro/nanoparticles, have attracted significant attention owing to their potential applications in various fields, ranging from microbioreactors to sensors. The volume of the LMs is a key parameter determining their mechanical stability and gas sensing ability. It is ideal to work with small volumes because of their better mechanical stability and gas sensing power compared to the larger LMs. Though many methods exist for producing LMs in the volume range above 2 µL, no reliable method exists to prepare fully coated submicroliter LMs with tunable volume. The situation becomes even more difficult when one attempts to produce tiny Janus Liquid Marbles (JLMs). This paper presents a simple, single-step, and efficient strategy for obtaining both the pristine LMs and JLMs in the volume range 200 nL to 18 µL. The core idea relies on the impact of a liquid drop on a particle bed at a Weber number of ∼55 to produce two daughter droplets and to convert these droplets into LMs/JLMs. The whole process takes only a few tens of milliseconds (∼50 ms). We have rendered the experimental schemes so that both the JLMs and pristine LMs can be produced in a single step, with control over their volume. The mechanical stability analysis of the prepared marbles indicates that 200 nL is 5 times more stable than 10 µL of LMs. The 0.72 µL LMs prepared with a 0.5 v/v % phenolphthalein indicator solution showed 3 times faster response time to ammonia gas sensing than 10 µL of LMs. The results presented in this work open up a new route for the rapid and reliable production of both multilayered LMs and JLMs with tunable volume in a wide range (200 nL to 18 µL).


Assuntos
Amônia , Nanopartículas , Carbonato de Cálcio , Fenolftaleínas
7.
Anal Chem ; 94(40): 13879-13888, 2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36170349

RESUMO

Viral outbreaks have caused great disruptions to the economy and public health in recent years. The accurate detection of viruses is a key factor in controlling and overcoming epidemics. In this study, an ultrasensitive molecularly imprinted virus sensor was developed based on an "explosive" secondary amplification strategy. Magnetic particles coated with carbon quantum dots (Fe3O4@CDs) were used as carriers and fluorescent probes, while aptamers were introduced into the imprinting layer to enhance the specific recognition of the target virus enterovirus 71 (EV71). When EV71 was captured by the imprinted particles, the fluorescence of the CDs was quenched, especially after binding to the aptamer-modified ZIF-8 loaded with a large amount of phenolphthalein, thereby resulting in signal amplification. Then, when adjusting the pH of the solution to 12, the decomposition of ZIF-8 released phenolphthalein, which turned the solution red, leading to the second "explosive" amplification of the signal. Therefore, the detection of EV71 with ultrasensitivity was achieved, which allows for visual detection by the naked eye in the absence of any instruments. The detection limits for fluorescence and visualization detection were 8.33 fM and 2.08 pM, respectively. In addition, a satisfactory imprinting factor of 5.4 was achieved, and the detection time only needed 20 min. It is expected that this fluorescence-colorimetric dual-mode virus molecularly imprinted sensor will show excellent prospects in epidemic prevention and rapid clinical diagnosis.


Assuntos
Substâncias Explosivas , Impressão Molecular , Pontos Quânticos , Vírus , Carbono/química , Corantes Fluorescentes/química , Limite de Detecção , Impressão Molecular/métodos , Fenolftaleínas , Pontos Quânticos/química
8.
Tissue Cell ; 78: 101886, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35985248

RESUMO

Human adipose stem cells (ASCs) hold great potential for regenerative medicine approaches, including osteogenic regeneration of bone defects, that fail to heal autonomously. Osteogenic differentiation of stem cells is dependent on the stimulation of biophysical factors. In the present study, the effects of hypergravity, hypoxia, and hyperbaric treatment were investigated on adipose stem cell (ASC) metabolic activity, quantified by PrestoBlue conversion, and cell numbers, evaluated by crystal violet staining. Osteogenic differentiation was assessed by alkaline phosphatase (ALP) activity and cresolphthalein staining of calcium deposition. Differentiation was performed for 12 days, which was accompanied by periodical stimulation. Increasing gravity forces up to 50x g did not affect ASC viability, but it enhanced osteogenic markers with a strongest effect between 20 and 30x g. Hyperbaric stimulation at 3 bar decreased ASC cell numbers but increased ALP activity and calcium deposition. Hypoxia at 8 % atmospheric oxygen did not affect ASC proliferation, while cell numbers were reduced at 3 % oxygen. Furthermore, hypoxic conditions produced opposing results on osteogenic markers, as ALP activity increased whereas cresolphthalein staining decreased upon stimulation. These data demonstrated that intermittent short duration of basal physical or chemical impulses interfere with the osteogenic differentiation of ASCs. Our findings could be of specific relevance in ASC based therapies for regenerative medicine and bone tissue engineering approaches.


Assuntos
Hipergravidade , Células-Tronco Mesenquimais , Tecido Adiposo , Fosfatase Alcalina/metabolismo , Cálcio/metabolismo , Diferenciação Celular , Células Cultivadas , Violeta Genciana/metabolismo , Violeta Genciana/farmacologia , Humanos , Hipóxia/metabolismo , Osteogênese , Oxigênio/metabolismo , Fenolftaleínas , Células-Tronco/metabolismo
9.
Food Chem ; 342: 128246, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33277123

RESUMO

In this study, we have reported an electrochemical sensor for the determination of butylated hydroxyanisole (BHA) by electropolymerization of O-cresolphthalein complexone (OC) over the multiwalled carbon nanotubes (MWCNTs). In order to confirm the surface morphology, oxidation states, functional groups and charge transfer property of POC/MWCNTs electrode, the resulting POC film with MWCNTs electrode was characterized by spectroscopy, microscopy, and electrochemical techniques. The fabricated electrode was evaluated for its electrochemical performance in oxidation of BHA and the study showed that at POC/MWCNTs electrodes BHA oxidation occurred at 0.27 V. POC/MWCNTs electrode has shown a linear range for the detection of BHA from 0.33 µM to 110 µM with the detection limit of 0.11 µM (S/N = 3). Amperometric determination of BHA was also done using chronoamperometric techniques and the result was found to be linear. The real time analysis of sensors is also validated by analysing the packed potato chips samples.


Assuntos
Hidroxianisol Butilado/análise , Eletroquímica/instrumentação , Análise de Alimentos/instrumentação , Nanotubos de Carbono/química , Fenolftaleínas/química , Hidroxianisol Butilado/química , Eletrodos , Oxirredução
10.
J Appl Lab Med ; 4(2): 201-213, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31639665

RESUMO

BACKGROUND: The tetrabromophenolphthalein ethyl ester (TBPE) assay has been used to quantify urinary albumin in point-of-care devices. We assessed the accuracy of this TBPE assay for urinary albumin through comparison with an established immunoturbidimetric method (ADVIA 1800 Chemistry System, Siemens). METHODS: We developed a TBPE assay protocol to quantify albumin in the range associated with microalbuminuria (0-200 mg/L). The Jaffe reaction and a 3-dimensional (3D) surface were used to compensate for creatinine interference. Spiked simulated urine samples and patient samples were used to compare the TBPE assay with the immunoturbidimetric method. Multiple linear regression was used to analyze factors that could account for discrepancies between the 2 methods. RESULTS: We found that creatinine interfered with the TBPE assay. To compensate, a 3D surface was successfully used to quantify albumin in spiked deionized water and simulated urine samples. In spiked simulated urine samples, the immunoturbidimetric method underestimated the albumin concentration by 2 to 45 mg/L, and the TBPE assay overestimated it by 9 to 82 mg/L. In patient samples, the albumin concentrations measured with the TBPE assay and the immunoturbidimetric method differed by an average of 184 mg/L. CONCLUSIONS: The TBPE assay is a function of the creatinine concentration, and a 3D surface can be used to provide accurate albumin concentrations for standard samples. The corrected TBPE method and the immunoturbidimetric method deviated from known concentrations of spiked samples. Further investigation and comparisons with a third albumin measurement method, such as LC-MS/MS, are necessary before conclusions on the accuracy of the TBPE assay can be made.


Assuntos
Albuminas/análise , Albuminúria/diagnóstico , Colorimetria/métodos , Imunoturbidimetria/métodos , Fenolftaleínas/química , Albuminúria/urina , Humanos , Testes Imediatos
11.
J Biomed Mater Res B Appl Biomater ; 107(5): 1607-1619, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30318825

RESUMO

To explore the effect of electrical stimulation (ES) on osteogenesis, a polypyrrole (PPy)-made electrical culture system was developed to provide a direct-current electric field (DCEF). This DCEF device was applied to treat differentiated rat bone marrow stromal cells (rBMSCs) once in different stages of osteo-differentation to investigate its temporal effects. The mineralization results showed that the DCEF treatment not only accelerated cell differentiation but also promoted the saturation levels, and the ES on day 8 was the group demonstrated the optimal result. The gene regulation analysis indicated that the DCEF treatment immediately increased the levels of genes related to osteo-differentiation, especially Runx2. Because Runx2 is a crucial transcriptional factor of osteogenesis, the ES-caused improvement of mineralization was likely contributed by the extension of its expression. Further, different ES modes were investigated of their efficacy on bone matrix deposition. Square waves with different parameters including frequency, offset, amplitude, and duty cycle were systematically examined. In contrast to constant voltage, square waves demonstrated periodical changes of current through substrate to significantly improve mineralization, and the efficiencies highly depended on both frequency and intensity. Through this comprehensive study, DCEF treating condition was optimized, which should be beneficial to its application on osteogenesis promotion. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 1607-1619, 2019.


Assuntos
Materiais Biocompatíveis/química , Estimulação Elétrica/métodos , Células-Tronco Mesenquimais/metabolismo , Osteogênese , Polímeros/química , Pirróis/química , Tecidos Suporte/química , Animais , Materiais Biocompatíveis/metabolismo , Calcificação Fisiológica/fisiologia , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Condutividade Elétrica , Matriz Extracelular/metabolismo , Humanos , Fenolftaleínas/química , Fenolftaleínas/metabolismo , Polímeros/metabolismo , Pirróis/metabolismo , Ratos , Ratos Sprague-Dawley , Propriedades de Superfície , Fatores de Tempo , Engenharia Tecidual
12.
Can Vet J ; 59(9): 988-992, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30197442

RESUMO

This study tested the hypothesis that the presence of prostaglandin E2 in seminal plasma would aid in the transport of phenolsulfonphthalein (PSP) across the uterotubal junction. Five mares in estrus were inseminated during estrus with PSP dissolved in phosphate-buffered saline and during the subsequent estrus with PSP added to a standard insemination dose. Serum and urine samples were obtained at hours 0, 1, 2, and 3 following treatment and examined for the presence of PSP. Phenolsulfonphthalein could not be detected in any of the urine samples collected from mares following either treatment. None of the serum samples collected following intrauterine installation of PSP in PBS contained PSP. Phenolsulfonphthalein was detected in serum samples from 1 mare following insemination with semen containing PSP. Components in seminal plasma such as PGE2 did not facilitate the transport of PSP across the uterotubal junction as had been hypothesized.


Le plasma séminal ne facilite pas le transport de la phénolsulfonphtaléine au travers de la jonction utéro-tubaire des juments. Cette étude a testé l'hypothèse voulant que la présence de la prostaglandine E2 dans le plasma séminal facilite le transport de la phénolsulfonphtaléine (PSP) au travers de la jonction utéro-tubaire. Cinq juments en oestrus ont été inséminées avec de la PSP dissoute dans une solution saline tamponnée au phosphate et, durant l'oestrus subséquent, avec de la PSP ajoutée à une dose d'insémination standard. Des prélèvements de sérum et d'urine ont été obtenus aux heures 0, 1, 2 et 3 ainsi qu'après le traitement et examinés pour déceler la présence de la PSP. La phénolsulfonphtaléine n'a pas pu être détectée dans aucun des échantillons d'urine prélevés auprès des juments après l'un ou l'autre des traitements. Aucun des échantillons de sérum prélevés après l'installation intra-utérine de la PSP dans PBS ne contenait de PSP. La phénolsulfonphtaléine a été détectée dans des échantillons de sérum provenant d'une jument après l'insémination avec du sperme contenant de la PSP. Des composants dans le plasma séminal comme le PGE2 n'ont pas facilité le transport de la PSP au travers de la jonction utéro-tubaire conformément à l'hypothèse émise.(Traduit par Isabelle Vallières).


Assuntos
Doenças dos Anexos/veterinária , Doenças dos Cavalos/diagnóstico , Fenolsulfonaftaleína/administração & dosagem , Doenças dos Anexos/diagnóstico , Animais , Dinoprostona , Estro , Feminino , Cavalos , Inseminação Artificial/veterinária , Masculino , Oviductos/fisiopatologia , Fenolftaleínas/sangue , Fenolftaleínas/urina , Fenolsulfonaftaleína/análise , Sêmen/química
13.
Drug Test Anal ; 9(6): 916-923, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27649484

RESUMO

Procedures for the extraction-spectrophotometric determination of tris(2-chloroethyl)amine, an alkylating agent known as a drug as well as a chemical warfare agent (nitrogen mustard HN-3), with 7 acid-base indicators of a triphenylmethane lactone type, phthaleins, were developed. Representatives of phthaleins without an oxygen bridge (thymolphthalein, o-cresolphthalein, naphtholphthalein) and with an oxygen bridge (fluorescein, 2',7'-dichlorofluorescein, eosin B and eosin Y) were used. The methods were based on the formation of ion pair complexes. Chloroform was used as a non-polar solvent for an extraction. The conditions to determine were optimized for the optimal pH of the buffer and the concentration of a phthalein as a reagent. The dependence on the reaction time in a water phase and the stoichiometry of extraction products were studied. The detection limits and the limits of the determination of separate procedures and conditional extraction constants were determined. Comparison with the spectrophotometric method of the group determination of alkyl halides and acyl halides using alkaline ethanol-water solution of thymolphthalein, the so-called T-135 agent, was conducted. While studying the selectivity, the possible interference of bis(2-chloroethyl)sulphide and 3 nitrogen mustards in the proposed procedures were verified. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Alquilantes/isolamento & purificação , Substâncias para a Guerra Química/isolamento & purificação , Compostos de Mostarda Nitrogenada/isolamento & purificação , Fenolftaleínas/química , Alquilantes/análise , Soluções Tampão , Substâncias para a Guerra Química/análise , Concentração de Íons de Hidrogênio , Limite de Detecção , Compostos de Mostarda Nitrogenada/análise , Espectrofotometria/métodos , Água/análise
14.
Mar Pollut Bull ; 101(2): 566-74, 2015 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-26522162

RESUMO

Number of heterotrophic bacteria ability to decompose organic phosphorus compounds and the level of phosphatase activity in the sand of two marine beaches (southern coast of the Baltic Sea) differing in the level of anthropopressure were studied. The study showed that the number of bacteria and level phosphatase activity were higher in the sand of the beach subjected to stronger anthropopressure. In both studied beaches bacteria hydrolysing DNA were the most numerous (92.7-302.8 CFU·g(-1) d.w.). The least numerous were phytin (26.0·10(3) CFU·g(-1) d.w.) and phenolphthalein diphosphate (11.1·10(3) CFU·g(-1) d.w.) decomposing bacteria. Number of bacteria able to attack tested organic phosphorus compounds were the most numerous in dry zones (10.77-739.92 CFU·g(-1) d.w.) then wet zones (3.34-218.15 CFU·g(-1) d.w.). In both studied beaches bacteria hydrolysing organic phosphorus compounds and phosphatase activity generally were more numerous in surface sand layer. Seasonal variation in the occurrence of bacteria in both studied beaches was observed.


Assuntos
Bactérias/metabolismo , Praias , Biodegradação Ambiental , Monoéster Fosfórico Hidrolases/metabolismo , Compostos de Fósforo/metabolismo , DNA/metabolismo , Sedimentos Geológicos/microbiologia , Processos Heterotróficos , Fenolftaleínas/metabolismo , Ácido Fítico/metabolismo , Polônia , Estações do Ano , Dióxido de Silício
15.
J Basic Clin Physiol Pharmacol ; 26(2): 141-5, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25046310

RESUMO

BACKGROUND: Investigation of the direct link between l-carnitine (LC), a quaternary ammonium compound that facilitates the passage of unsaturated fatty acids into the mitochondrial matrix, and free calcium (Ca2+) is needed to explain a number of varying results obtained from different in vitro and in vivo studies of LC as a supplement. METHODS: The chemical structure of LC, which contains oxygen ligand atoms, prompted to measure its activity asa Ca2+ chelator. The measurement was carried out spectrophotometri cally by measuring the reduction in the formation of Ca2+-o-cresolphthalein complexone (Ca-CPC) in the presence of different doses of LC (0.075, 0.75, and 7.5 mM) compared to the control (0.0 mM LC). RESULTS: The effect of LC was measured as a free entity in solution and when added to human serum. Our results showed a significant decrease (p < 0.05) in the average absorbance of Ca-CPC in the presence of LC compared to the control. CONCLUSIONS: In conclusion, LC exhibits a significant Ca2+ chelating activity. As Ca2+ is vital in the biochemical and physiological processes of living cells, LC could be affecting the calcium-dependent biological systems by limiting the levels of free Ca2+. Examples include decelerating the blood clotting process, amplifying the effect of anticoagulants, reducing nitric oxide synthase activity, inhibiting


Assuntos
Quelantes de Cálcio/farmacologia , Cálcio/metabolismo , Carnitina/farmacologia , Quelantes de Cálcio/administração & dosagem , Quelantes de Cálcio/química , Carnitina/administração & dosagem , Carnitina/química , Suplementos Nutricionais , Relação Dose-Resposta a Droga , Humanos , Fenolftaleínas/metabolismo
16.
Rinsho Byori ; 62(2): 133-8, 2014 Feb.
Artigo em Japonês | MEDLINE | ID: mdl-24800488

RESUMO

The ionized or free fraction of serum calcium is physiologically important for cellular function, but we most often measure total serum calcium. There are a number of correction formulas that can be used to estimate whether low total serum calcium can be attributed simply to low albumin or serum protein. In Japan, Payne's formula has been widely used to correct calcium concentration. However, there are some problems in the measurement methods of total calcium and serum albumin which were used to establish Payne's formula with respect to specificity, calibration curve and stability. Recently, improved measurement methods of calcium and albumin have been adopted at clinical laboratories. Here we evaluated Payne's formula by comparing it with improved measurement methods of total calcium and serum albumin. For the total calcium measurement, o-CPC (o-cresolphthaleincomplexone), CPZ(chlorophosphonazo) III, and enzymatic methods were used. For the serum albumin measurement, BCG (bromocresol green) and improved BCP(bromocresol purple) methods were used. The results of this comparison study suggest that the calcium correction equation is not affected by changes in total calcium concentration, but the assay used for albumin may affect the calcium correction equation. Using multiple linear regression, the following equations were derived: BCG between CPZ III [corrected Ca(mg/dL) = total Ca-0.76ALB + 3.2], and improved BCP between CPZ III [corrected Ca = total Ca-0.7ALB + 2.6]. These formulas are simplified respectively as [corrected Ca = total Ca + 0.8(4-ALB], and [corrected Ca = total Ca + 0.7 (4-ALB)]. We conclude that Payne's formula is valid with the BCG method, but with the improved BCP method, our formula is more suitable for correcting calcium.


Assuntos
Análise Química do Sangue , Proteínas Sanguíneas/análise , Cálcio/sangue , Albumina Sérica/análise , Análise Química do Sangue/métodos , Humanos , Japão , Fenolftaleínas/análise
17.
Biopharm Drug Dispos ; 35(5): 275-83, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24615849

RESUMO

The interaction between mycophenolate (MPA) and quinolone antibiotics such as ciprofloxacin is considered to reduce the enterohepatic recycling of MPA, which is biotransformed in the intestine from MPA glucuronide (MPAG) conjugate excreted via the biliary system; however, the molecular mechanism underlying this biotransformation of MPA is still unclear. In this study, an in vitro system was established to evaluate ß-glucuronidase-mediated deconjugation and to examine the influence of ciprofloxacin on the enzymatic deconjugation of MPAG and MPA resynthesis. Resynthesis of MPA via deconjugation of MPAG increased in a time-dependent manner from 5 to 60 min in the presence of ß-glucuronidase. Ciprofloxacin and phenolphthalein-ß-d-glucuronide (PhePG), a typical ß-glucuronidase substrate, significantly decreased the production of MPA from MPAG in the ß-glucuronidase-mediated deconjugation system. In addition, enoxacin significantly inhibited the production of MPA from MPAG, while levofloxacin and ofloxacin had no inhibitory effect on MPA synthesis. Pharmacokinetic analysis revealed that ciprofloxacin showed a dose-dependent inhibitory effect on MPA production from MPAG via ß-glucuronidase with a half-maximal inhibitory concentration (IC50 ) value of 30.4 µm. While PhePG inhibited the ß-glucuronidase-mediated production of MPA from MPAG in a competitive manner, ciprofloxacin inhibited MPA synthesis via noncompetitive inhibition. These findings suggest that the reduction in the serum MPA concentration during the co-administration of ciprofloxacin is at least in part due to the decreased enterohepatic circulation of MPA because of noncompetitive inhibition of deconjugation of MPAG by intestinal ß-glucuronidase.


Assuntos
Ciprofloxacina/farmacologia , Glucuronidase/metabolismo , Glucuronídeos/farmacocinética , Ácido Micofenólico/análogos & derivados , Ácido Micofenólico/farmacocinética , Antibacterianos/administração & dosagem , Antibacterianos/farmacologia , Ciprofloxacina/administração & dosagem , Relação Dose-Resposta a Droga , Enoxacino/farmacologia , Circulação Êntero-Hepática/efeitos dos fármacos , Imunossupressores/administração & dosagem , Imunossupressores/farmacocinética , Técnicas In Vitro , Concentração Inibidora 50 , Levofloxacino/farmacologia , Ofloxacino/farmacologia , Fenolftaleínas/farmacologia , Fatores de Tempo
18.
J Am Chem Soc ; 135(25): 9311-4, 2013 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-23745607

RESUMO

Deduced from thermodynamics and the Thomson-Gibbs equation that the surface energy of crystal face is in proportion to the supersaturation of crystal growth units during the crystal growth, we propose that the exposed crystal faces can be simply tuned by controlling the supersaturation, and higher supersaturation will result in the formation of crystallites with higher surface-energy faces. We have successfully applied it for the growth of ionic (NaCl), molecular (TBPe), and metallic (Au, Pd) micro/nanocrystals with high-surface-energy faces. The above proposed strategy can be rationally designed to synthesize micro/nanocrystals with specific crystal faces and functionality toward specific applications.


Assuntos
Ouro/química , Nanopartículas/química , Paládio/química , Fenolftaleínas/química , Cloreto de Sódio/química , Íons/química , Estrutura Molecular , Tamanho da Partícula , Propriedades de Superfície , Termodinâmica
19.
Talanta ; 107: 61-6, 2013 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-23598193

RESUMO

A new methodology based on fluorescent signal enhancement of o-cresolphthalein (o-CPT) for traces of cadmium determination is proposed. The dye was retained on membrane filters in the presence of a micellar surfactant solution of carbon nanotubes (CNTs). All the experimental variables that influence both the preconcentration procedure and the fluorimetric sensitivity were carefully optimized. The calibration graph using zeroth order regression was linear from 6.5 ng L(-1) to 5.65×10(5) ng L(-1), with a correlation coefficient higher than 0.999. Under optimal conditions, the limits of detection and quantification were of 2 ng L(-1) and 6.5 ng L(-1). respectively. The proposed method showed good sensitivity and selectivity, with good tolerance to foreign ions, and it was applied to the determination of trace amounts of cadmium in leachate from cigarettes' tobacco samples with satisfactory results. The trueness of the recommended procedure was assessed through parallel analysis of the samples with electrothermal atomization atomic absorption spectrometry. This methodology represents an innovative and attractive application of membrane filters that enables metal traces determination by solid surface fluorescence.


Assuntos
Cádmio/análise , Nanotubos de Carbono/química , Nylons/química , Espectrometria de Fluorescência/métodos , Produtos do Tabaco/análise , Poluentes Químicos da Água/análise , Corantes Fluorescentes/química , Limite de Detecção , Membranas Artificiais , Fenolftaleínas/química , Tensoativos/química
20.
J Med Chem ; 56(6): 2406-14, 2013 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-23437772

RESUMO

Colloidal aggregation is the dominant mechanism for artifactual inhibition of soluble proteins, and controls against it are now widely deployed. Conversely, investigating this mechanism for membrane-bound receptors has proven difficult. Here we investigate the activity of four well-characterized aggregators against three G protein-coupled receptors (GPCRs) recognizing peptide and protein ligands. Each of the aggregators was active at micromolar concentrations against the three GPCRs in cell-based assays. This activity could be attenuated by either centrifugation of the inhibitor stock solution or by addition of Tween-80 detergent. In the absence of agonist, the aggregators acted as inverse agonists, consistent with a direct receptor interaction. Meanwhile, several literature GPCR ligands that resemble aggregators themselves formed colloids, by both physical and enzymological tests. These observations suggest that some GPCRs may be artifactually antagonized by colloidal aggregates, an effect that merits the attention of investigators in this field.


Assuntos
Coloides/química , Coloides/farmacologia , Receptores Acoplados a Proteínas G/metabolismo , Linhagem Celular , Clotrimazol/química , Clotrimazol/farmacologia , Itraconazol/química , Itraconazol/farmacologia , Ligantes , Modelos Moleculares , Fenolftaleínas/química , Fenolftaleínas/farmacologia , Conformação Proteica , Quercetina/química , Quercetina/farmacologia , Receptores Acoplados a Proteínas G/química , Transdução de Sinais/efeitos dos fármacos
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