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1.
Akush Ginekol (Sofiia) ; 55 Suppl 1 Pt 2: 29-35, 2016.
Artigo em Búlgaro | MEDLINE | ID: mdl-27509667

RESUMO

UNLABELLED: The aim of this review is to discuss the possibilities and disadvantages of the techniques for visual inspection of the uterine cervix with acetic acid (VIA) and with Lugol's iodine (VILI) for early detection of cervical neoplasia. Efficient cervical screening method, approved in practice, is cytology--PAP smear. The lack of organized screening program in Bulgaria is the reason why a lot of cases of cervical cancer are missed or diagnosed late. This raises the question for searching alternative tests to assess the uterine cervix that do not use special techniques and have a reasonable cost. Published results show that VIA and VILI represent an appropriate alternative for cervical screening. The results of VIA and VILI are immediately available and do not require any laboratory processing. CONCLUSION: Both types of visual inspection of the uterine cervix are easy to accomplish, fast--the result is available at the moment of inspection, they do not require special equipment, the correlation between sensitivity and specificity is good and last but not least--they have low price. VIA and VILI have certain position in our practice.


Assuntos
Ácido Acético/análise , Colo do Útero/patologia , Iodetos/análise , Neoplasias do Colo do Útero/diagnóstico , Bulgária/epidemiologia , Detecção Precoce de Câncer/economia , Detecção Precoce de Câncer/métodos , Feminino , Humanos , Programas de Rastreamento/economia , Programas de Rastreamento/métodos , Neoplasias do Colo do Útero/epidemiologia
2.
Anal Chim Acta ; 891: 269-76, 2015 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-26388386

RESUMO

Au@Ag core-shell nanoparticles (NPs) were synthesized and coupled with copper ion (Cu(2+)) for the colorimetric sensing of iodide ion (I(-)). This assay relies on the fact that the absorption spectra and the color of metallic core-shell NPs are sensitive to their chemical ingredient and dimensional core-to-shell ratio. When I(-) was added to the Au@Ag core-shell NPs-Cu(2+) system/solution, Cu(2+) can oxidize I(-) into iodine (I2), which can further oxidize silver shells to form silver iodide (AgI). The generated Au@AgI core-shell NPs led to color changes from yellow to purple, which was utilized for the colorimetric sensing of I(-). The assay only took 10 min with a lowest detectable concentration of 0.5 µM, and it exhibited excellent selectivity for I(-) over other common anions tested. Furthermore, Au@Ag core-shell NPs-Cu(2+) was embedded into agarose gels as inexpensive and portable "test strips", which were successfully used for the semi-quantitation of I(-) in dried kelps.


Assuntos
Colorimetria/métodos , Cobre/química , Água Potável/análise , Ouro/química , Iodetos/análise , Nanopartículas Metálicas/química , Prata/química , Cátions Bivalentes/química , Colorimetria/economia , Limite de Detecção , Nanopartículas Metálicas/ultraestrutura , Fitas Reagentes/análise , Sefarose/química
3.
Analyst ; 138(6): 1898-902, 2013 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-23391999

RESUMO

A simple and sensitive chemiluminescence assay for iodide (I(-)) detection was reported, which was based on iodide extracting Hg(2+) from DNA featuring a stem-loop structure containing T-Hg(2+)-T. Specifically, Hg(2+) induced random coiled G-rich single-strand DNA to form a stem-loop structure containing T-Hg(2+)-T. Because the binding of Hg(2+) and I(-) is much stronger than that of Hg(2+) and thymine (T), I(-) could extract Hg(2+) from the stem-loop structure, releasing the DNA, which then bound with K(+) and transformed into a K(+)-stabilized G-quadruplex (with hemin as a cofactor), which catalyzed the H(2)O(2)-mediated oxidation of luminol. The produced chemiluminescence as a sensing signal was applied to sensitively and selectively detect iodide with a detection limit of 12 nM. This system exhibited the first DNAzyme-based iodide sensor. Finally, the sensor was successfully applied for iodide detection in real lake water samples.


Assuntos
DNA/química , Iodetos/análise , Medições Luminescentes/métodos , Timina/química , Cátions Bivalentes/análise , Quadruplex G , Hemina/química , Peróxido de Hidrogênio/química , Limite de Detecção , Medições Luminescentes/economia , Luminol/química , Mercúrio/isolamento & purificação , Oxirredução
4.
J Environ Monit ; 13(8): 2312-20, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21738937

RESUMO

Perchlorate is known to competitively interfere with iodide uptake by the thyroid gland and thereby human exposure to perchlorate is a public health concern. Prevalence of perchlorate in dairy milk is documented; nevertheless, co-occurrence of perchlorate with other thyroid-binding monovalent ions such as iodide and nitrate is not well understood. In this study, we analyzed perchlorate, iodide, and nitrate-N in dairy milk, water and other dairy-related samples collected from Japan and Sri Lanka. Concentrations of perchlorate in Japanese dairy milk samples ranged from 1.03 to 14.1 ng ml(-1); the corresponding concentrations in dairy milk and powdered milk from Sri Lanka were 1.14-38.5 ng ml(-1). Perchlorate concentrations in commercial milk were significantly higher in Japan than in Sri Lanka, while iodide and nitrate levels in milk between the two countries were comparable. All three ions were ubiquitously found in water samples from Japan and Sri Lanka. Analysis of colostrum and raw milk collected from cows fed with the same feed for over 30 days showed no significant temporal variations in perchlorate, iodide and nitrate-N concentrations. A significant positive correlation was found between the concentrations of perchlorate and iodide in Japanese commercial milk. The concentrations of perchlorate and nitrate-N in water samples analyzed from both countries also showed a significant positive correlation. The exposure estimation revealed that dairy milk provides a greater source for perchlorate and iodide, while water predominantly contributes nitrate-N intake for all age groups in both counties. Infants and children demonstrated the highest estimated perchlorate, iodide and nitrate-N intake on a body weight basis in comparison to other age groups. Therefore, further studies of risk associated with perchlorate may need to reconsider co-existence of iodine and other iodide transport inhibitors in food.


Assuntos
Exposição Ambiental , Iodetos/análise , Leite/química , Nitratos/análise , Percloratos/análise , Água/análise , Animais , Bovinos , Iodetos/toxicidade , Japão , Nitratos/toxicidade , Percloratos/toxicidade , Sri Lanka , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
5.
J Chromatogr B Analyt Technol Biomed Life Sci ; 879(9-10): 573-8, 2011 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-21330222

RESUMO

The aim of the study was to examine correlations between the content of iodides in 66 nodular goiters and 100 healthy human thyroid tissues (50- frozen and 50 formalin-fixed). A fast, accurate and precise ion chromatography method on IonPac AS11 chromatographic column (Dionex, USA) with a pulsed amperometric detection (IC-PAD) followed by alkaline digestion with tetramethylammonium hydroxide (TMAH) in a closed system and with the assistance of microwaves was developed and used for the comparative analysis of two types of human thyroid samples. Statistical analysis revealed over eightfold reduction of iodine concentration in the pathological tissues (the mean value was 77.13±14.02 ppm) in comparison with the control group (622.62±187.11 ppm for frozen samples and 601.49±192.11 ppm for formalin-fixed ones). A good correspondence (for 10 additional determinations) between the certified (3.38±0.02 ppm with variation coefficient (V.C.) of 0.59% for Standard Reference Material (SRM) NIST 1549-non-fat milk powder) and the measured iodine concentrations (3.52±0.29 ppm; V.C.=10%) was achieved. It was pointed out that the way of tissue preservation (either in formalin or by freezing) had no significant effect on the iodine determination result (α=0.1). Significantly lower iodide content was found in nodular goiter thyroid samples. The applied conditions of digestion, reinforced by the action of microwaves, brought about a decidedly shorter (less than 20 min) sample preparation time. Suitability of the developed IC method was supported by validation results.


Assuntos
Cromatografia por Troca Iônica/métodos , Bócio Nodular/metabolismo , Iodetos/análise , Glândula Tireoide/química , Adulto , Interpretação Estatística de Dados , Feminino , Humanos , Masculino , Compostos de Amônio Quaternário , Reprodutibilidade dos Testes , Glândula Tireoide/metabolismo , Preservação de Tecido
6.
Radiat Prot Dosimetry ; 144(1-4): 402-6, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21183546

RESUMO

The in vivo monitoring Lab at KIT uses two phoswich detectors for routine lung counting. A simplified model of one of them has been implemented in the two Monte Carlo codes EGSnrc and MCNPX. The active part of the detector consists of a crystal of NaI(Tl) and one of CsI(Tl): the energy deposited in both the crystals have been studied to consider the effect of the anticoincidence logic, present in the read-out electronics of the detectors and not yet studied with Monte Carlo simulations. Only the NaI(Tl) crystal has then been used to study the escape peaks at several energies, which are more prominent at low energies. The results from the two codes have been compared. The comparison of the codes predictions for the escape peaks has been then extended using the model of a germanium detector.


Assuntos
Pulmão/efeitos da radiação , Monitoramento de Radiação/instrumentação , Radiometria/instrumentação , Algoritmos , Amerício/análise , Césio/análise , Desenho de Equipamento , Germânio/análise , Humanos , Iodetos/análise , Método de Monte Carlo , Fótons , Monitoramento de Radiação/métodos , Radiometria/métodos , Iodeto de Sódio/análise , Software
7.
Talanta ; 82(2): 828-33, 2010 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-20602977

RESUMO

A simple, precise and accurate automatic method for the determination of total iodine in milk products by indirect atomic absorption spectrometry is proposed. Iodide in solutions resulting from alkaline ashing of samples is precipitated with silver ion in a precipitation-dissolution flow manifold, which allows performing on-line the retention of the silver iodide precipitate formed on a filter, its wash with diluted ammonia and its dissolution with a diluted thiosulfate solution. Dissolved silver is also determined on-line by flame atomic absorption, and the achieved amount of this metal is proportional to that of iodine in the sample. The proposed method is very selective, avoids interferences from anions present in the samples, which can be also precipitated with silver, because these silver compounds are dissolved with ammonia at the washing step. This method allows the determination of iodine in the range 0.011-0.35 microg mL(-1) with a relative standard deviation between 1.3 and 6.8% at a rate of ca. 17 samplesh(-1).


Assuntos
Iodetos/análise , Leite/química , Animais , Automação , Bioensaio/economia , Espectrofotometria Atômica/métodos , Fatores de Tempo
8.
J Pharm Biomed Anal ; 25(3-4): 363-77, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11377015

RESUMO

USP 1995 (The United States Pharmacopeia, 23rd Edit., (1995), potassium iodide p. 1265, sodium iodide p. 1424), PH. EUR. 1997 (European Pharmacopoeia, third ed., Council of Europe, Strasbourg, (1997), potassium iodide p. 1367, sodium iodide p. 1493) and JAP 1996 (The Japanes Pharmacopoeia, 13th ed. (1996), potassium iodide p. 578, sodium iodide p. 630) determine iodide with the ICl-method (J. Am. Chem. Soc. 25 (1903) 756-761; Z. Anorg. Chem. 36 (1903) 76-83; Fresenius Z. Anal. Chem. 106 (1936) 12-23; Arzneibuch-Kommentar, Wissenschaftliche Erläuterungen zum Europäischen Arzneibuch, Wissenschaftliche Verlagsgesellschaft mbH, Stuttgart, Govi-Verlag - Pharmazeutischer Verlag GmbH, Eschborn, 12th suppl. (1999), K10 p. 2), using chloroform, which is toxic and hazardous to environment. Without the application of chlorinated hydrocarbons USP 2000 (The United State Pharmacopeia, 24th ed. (2000), potassium iodide p. 1368, sodium iodide p. 1535) and Brit 1999 (British Pharmacopoeia London, (1999), Appendix VIII C, p. A162) titrate iodide with the redox indicator amaranth. A titration with potentiometric indication giving two end-points at the step of I(2) and [ICl(2)](-) is described. Due to the high concentration of hydrochloric acid required for the ICl-method, the determination with DBH (1,3-dibromo-5,5-dimethylhydantoin; 1,3-dibromo-5,5-dimethyl-2,4-imidazolidinedione) can be recommended and is performed easily. Similarly, the iodide content of gallamine triethiodide may be analyzed with DBH by application of a visual two-phase titration in water and ethyl acetate or with potentiometric indication in a mixture of 2-propanol and water. During the removal of the excess of DBH 4-bromo-triethylgallamine (2,2',2"-[1-bromo-benzene-2,3,4-triyltris(oxy)]N,N,N-triethylethanium) is formed.


Assuntos
Iodetos/análise , Farmacopeias como Assunto , Hidantoínas , Espectroscopia de Ressonância Magnética
9.
Artigo em Inglês | MEDLINE | ID: mdl-11063093

RESUMO

Natural Rubber (NR) in both its latex and dried form was treated with iodine to make it antibacterial in nature. The NR latex was dried and washed, dissolved in toluene, iodinated and cast into films. In a different approach, NR in its latex form (emulsion) was blended with aqueous solution of povidone-iodine complex (PVP-I) and films were cast. Phase separation of PVP-I was observed in the films prepared using NR latex; whereas the film prepared using NR solution in toluene and molecular iodine were homogeneous, transparent light brown. Solubility assessment of the films revealed that unlike pure NR, the iodinated NR failed to go into solution completely. The films obtained from both the approaches were evaluated for release of iodide ions. On immersion in water, PVP-I blended latex did not retain iodine while sustained release of iodide ion was observed in case of dried NR dissolved in toluene and treated with iodine. The FT-IR spectra of the iodinated films revealed that iodine attaches covalently to the double bonds in the isoprene units of NR. The films were also evaluated for their antibacterial properties and it was observed that the films prepared from both the approaches, acquired antimicrobial properties.


Assuntos
Antibacterianos/farmacologia , Iodo/química , Borracha/farmacologia , Antibacterianos/química , Dessecação , Escherichia coli/efeitos dos fármacos , Iodetos/análise , Teste de Materiais , Testes de Sensibilidade Microbiana , Povidona-Iodo/química , Borracha/química , Solubilidade , Solventes , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus/efeitos dos fármacos , Tolueno , Água
10.
Z Ernahrungswiss ; 34(2): 131-6, 1995 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-8525645

RESUMO

Iodized salt has a high acceptance in the Potsdam region: 82% of the interviewed people use iodized salt, 13% do not use it, and only 5% of the probands were not able to make any statements. The current average iodine intake for adults is 76 micrograms/day. Only 5% of the adult population has an iodine intake of more than 100 micrograms/day. An efficient elimination of iodine deficiency in Germany requires a broad usage of iodized salt in the food industry.


Assuntos
Peixes , Iodetos/metabolismo , Carne , Sódio na Dieta , Adulto , Animais , Dieta , Alemanha , Humanos , Iodetos/análise , Carne/análise , Água do Mar , Especificidade da Espécie
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