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1.
PLoS One ; 15(9): e0238783, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32946473

RESUMO

Diffusible iodine-based contrast-enhanced computed tomography (diceCT) techniques allow visualization of soft tissues of fluid-preserved specimens in three dimensions without dissection or histology. Two popular diceCT stains, iodine-potassium iodide (I2KI) dissolved in water and elemental iodine (I2) dissolved in 100% ethanol (EtOH), yield striking results. Despite the widespread use of these stains in clinical and biological fields, the molecular mechanisms that result in color change and radiopacity attributed to iodine staining are poorly understood. Requests to apply these stains to anatomical specimens preserved in natural history museums are increasing, yet curators have little information about the potential for degradation of treated specimens. To assess the molecular effects of iodine staining on typical museum specimens, we compared the two popular stains and two relatively unexplored stains (I2KI in 70% EtOH, I2 in 70% EtOH). House sparrows (Passer domesticus) were collected and preserved under uniform conditions following standard museum protocols, and each was then subjected to one of the stains. Results show that the three ethanol-based stains worked equally well (producing fully stained, life-like, publication quality scans) but in different timeframes (five, six, or eight weeks). The specimen in I2KI in water became degraded in physical condition, including developing flexible, demineralized bones. The ethanol-based methods also resulted in some demineralization but less than the water-based stain. The pH of the water-based stain was notably acidic compared to the water used as solvent in the stain. Our molecular analyses indicate that whereas none of the stains resulted in unacceptable levels of protein degradation, the bones of a specimen stained with I2KI in water demineralized throughout the staining process. We conclude that staining with I2KI or elemental I2 in 70% EtOH can yield high-quality soft-tissue visualization in a timeframe that is similar to that of better-known iodine-based stains, with lower risk of negative impacts on specimen condition.


Assuntos
Preservação Biológica/métodos , Coloração e Rotulagem , Microtomografia por Raio-X/métodos , Animais , Aves/anatomia & histologia , Meios de Contraste/química , Iodo/química , Museus
2.
Chemistry ; 26(43): 9430-9444, 2020 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-32227537

RESUMO

The last decade has witnessed the rapid development of high-valent Pd-involved organic transformations. This has also led to a steadily growing number of publications concerning the preparation of isolable and characterizable palladium(III) and palladium(IV) complexes. A variety of one-electron and two-electron oxidants have been employed to give access to high-oxidation-state Pd compounds. Undoubtedly, the study of these stoichiometric reactions has great implications for relevant Pd-mediated catalysis. In this minireview, the focus is on the synthetic approaches to structurally determined PdIII/IV complexes starting from their PdII precursors, and the advances in this research area from early 2010 to late 2019 will be highlighted. Chemical oxidations exploiting various oxidizing agents including 1) hypervalent iodine reagents; 2) halogens; 3) electrophilic fluorination reagents; 4) alkyl/aryl halides; 5) ferrocenium salts; 6) peroxides/O2 ; 7) sulfonyl chlorides; and 8) others are covered. A "greener" electrooxidation manner has also been reviewed.


Assuntos
Compostos Ferrosos/química , Paládio/química , Catálise , Elétrons , Halogenação , Halogênios/química , Indicadores e Reagentes/química , Iodo/química , Oxirredução
3.
Int J Pharm Compd ; 24(1): 83-85, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32023220

RESUMO

Melphalan is used in selective ophthalmic artery infusion chemotherapy. In the procedure to catheterize the ophthalmic artery in selective ophthalmic artery infusion chemotherapy, the microcatheter is usually filled with an iodinated contrast medium. It is not known whether mixing of iodinated contrast medium with melphalan solutions promotes precipitation of melphalan during selective ophthalmic artery infusion chemotherapy. The objective of the present study was to examine the compatibility of melphalan and iodinated contrast medium. In the experiments, melphalan solutions were prepared with and without iodinated contrast medium (iohexol 300 mg Iodine/mL or ioversol 74%). Melphalan solution of clinically relevant concentration (0.45 mg/mL) in the absence of iodinated contrast medium was evaluated as a reference. The 0.45-mg/mL melphalan solution was diluted with iodinated contrast medium at 1:9 and 1:1 ratios to form solutions comprising iodinated contrast medium at 10% or 50% (v/v), and each was evaluated. The formation of particles was examined using filtration (pore size 0.45 µm) followed by high-performance liquid chromatography at four quarterly time intervals (15 min, 30 min, 45 min, and 60 min) over a 1-hour period after solution preparation. High-performance liquid chromatography analysis of microfiltered solutions did not reveal evidence of melphalan crystal formation over a 60-minute period for the solutions studied. The filtration studies suggest that mixing of the iodinated contrast medium with melphalan solutions does not result in significant melphalan precipitation.


Assuntos
Meios de Contraste/administração & dosagem , Iodo , Iohexol/administração & dosagem , Melfalan , Iodo/química , Artéria Oftálmica
4.
Top Curr Chem (Cham) ; 378(2): 22, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-32030596

RESUMO

Heterocyclic compounds having a nitrogen atom in the ring exhibit very interesting biological activities. Indole is the core structure of many bioactive compounds owing to its high affinity to bind with most biological targets. Indole is an electron-rich compound and generally prefers electrophilic rather than nucleophilic substitution. Hence, many important indole derivatives are difficult to synthesize through the conventional reactivity of indole. This limitation can be avoided by using the umpolung, from the German word meaning polarity inversion. In umpolung, the indole molecule, especially the C2 and C3 positions, behave as an electrophile. As C2-functionalized indoles have substantial importance in synthetic and pharmaceutical chemistry, this review focuses on the C2 umpolung of indoles via the indirect approach which is less explored. Unlike direct approaches of indole umpolung, indirect methods have several advantages and therefore a number of research articles have been published in this field. But no review is available up till now. This is the first review on this topic and we believe that it will surely motivate the readers to work in this area further.


Assuntos
Carbono/química , Indóis/química , Alcaloides/síntese química , Alcaloides/química , Catálise , Ciclização , Iodo/química , Quinolinas/síntese química , Quinolinas/química , Ácidos Sulfínicos/química
5.
Org Lett ; 22(4): 1290-1294, 2020 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-31999466

RESUMO

2-Aminobenzimidazole cores are among the most common structural components in medicinal chemistry and can be found in many biologically active molecules. Herein, we report a mild protocol for the synthesis of multifunctional 2-aminobenzimidazoles on-DNA with broad substrate scopes. The reaction conditions expand our ability to design and synthesize 2-aminobenzimidazole core-focused DNA-encoded libraries.


Assuntos
Benzimidazóis/síntese química , DNA/química , Iodo/química , Benzimidazóis/química , Ciclização , Estrutura Molecular , Estereoisomerismo
6.
Spectrochim Acta A Mol Biomol Spectrosc ; 224: 117444, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31394388

RESUMO

The application of fluorescent carbon dots in bio-imaging has huge positive significance in the field of biomedicine. By taking this advantage, herein we prepared nitrogen, sulfur and iodine doped carbon dots (N,S,I-CDs) by a facile hydrothermal reaction using C3N3S3, potassium iodate (KIO3) and ethylenediamine (EDA), and the obtained N,S,I-CDs show bright blue fluorescence with a high fluorescence quantum yield of about 32.4%. The prepared N, S, I-CDs could interact with the folic acid (FA) with high selectivity, lead to development of a high sensitive method for the FA detection from 0.1 to 175 µM wide linear range with a detection limit of 84 nM (S/N = 3) and also applied them in U-2 OS cells imaging. Moreover, this sensor possessed a good sensitivity, linearity and reversibility in the temperature range of 10-80 °C, and successfully applied for the temperature sensing in cell HT-29 samples. This investigation illustrates that as-prepared N, S, I-CDs probe may have great potential as a high-performance platform for the accurate recognition of temperature in cells and could provide a new tool for the detection of FA in cells.


Assuntos
Técnicas Biossensoriais/métodos , Técnicas Citológicas/métodos , Ácido Fólico/análise , Pontos Quânticos/química , Linhagem Celular Tumoral , Transferência Ressonante de Energia de Fluorescência/métodos , Humanos , Iodo/química , Nitrogênio/química , Enxofre/química , Temperatura
7.
Mater Sci Eng C Mater Biol Appl ; 107: 110220, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31761246

RESUMO

ZnO nanoparticles doped with I and Ag were prepared via a solvothermal method. Characterizations of the as-synthesised samples were carried out using X-ray diffraction, X-ray photoelectron spectroscopy, UV-Vis spectrometry, Photoluminescence, transmission electron microscopy and scanning electron microscopy. The nanoparticles exhibit light absorption for wide spectra from ultra-violet (UV) to visible light. The antimicrobial efficacy was evaluated against Escherichia coli (MG1655) and Staphylococcus aureus (USA300) as models of Gram-negative and Gram-positive microorganisms, respectively. The double-doped nanoparticles demonstrated their potent efficacy against both types of microorganisms and they may have great potential in combating infectious diseases. More importantly, the insights into the mechanisms underlying the antimicrobial effects were revealed: synergistic effect of reactive oxygen species (ROS) generation and Ag+ release. Specifically, the ROS generation was believed to be dominant in the I:Ag:ZnO sample under visible light, while both ROS generation and Ag+ release were found to play an important role in the bacteria-killing by Ag:I:ZnO in the visible light and dark conditions. The Ag+ release was found to be the dominant antimicrobial mechanism for the Ag:ZnO NP sample in our experiment.


Assuntos
Antibacterianos/química , Iodo/química , Luz , Nanopartículas/química , Prata/química , Óxido de Zinco/química , Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Nanopartículas/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Staphylococcus aureus/efeitos dos fármacos
8.
Org Biomol Chem ; 17(48): 10245-10250, 2019 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-31793609

RESUMO

A general and simple metal-free protocol for expedient C-H functionalization leading to the regioselective generation of C-5 chalcogenated 8-aminoquinoline analogues in up to 90% yield at room temperature (25 °C) has been established. This methodology is an eco-friendly approach to the atom-economical utilization of diaryl/dialkyl chalcogenides for direct access to chalcogenated quinolines and is scalable to the gram scale without considerable decrease in the yield of the product. It represents a practical alternative to the existing metal-catalyzed functionalization of 8-aminoquinoline derivatives with broad functional group tolerance. The controlled experiments suggest that the reaction possibly proceeds through an ionic pathway at room temperature. Furthermore, the potentiality for the functionalization of free amines in chalcogenated-8-aminoquinolines provides an attractive perspective for further elaboration of the amine substituent through chemical manipulations. The applicability of the standardized method has been augmented through late-stage antimalarial drug diversification of primaquine analogues.


Assuntos
Aminoquinolinas/síntese química , Aminas/química , Catálise , Iodo/química , Estrutura Molecular , Oxirredução , Ácido Selênico/química , Solventes/química , Estereoisomerismo , Ácidos Sulfênicos/química
9.
Chem Pharm Bull (Tokyo) ; 67(12): 1259-1270, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31787652

RESUMO

The biary unit having heteroatom as important scaffolds widely exist in a large number of biologically active compounds and functional organic molecules. Since the cross-coupling is a useful synthetic method for constructing biaryl and heterobiaryl structures, the development of novel cross-coupling methods has been studied intensively. The oxidative biaryl coupling reaction of aromatic compounds having heteroatoms is an attractive method since they do not require the prefunctionalization of arenes. This report describes recent advances in hypervalent iodine(III) induced metal-free synthesis of biaryls having heteroatoms.


Assuntos
Compostos Heterocíclicos/síntese química , Compostos Heterocíclicos/química , Iodo/química , Estrutura Molecular , Oxirredução
10.
J Mol Model ; 26(1): 6, 2019 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-31834479

RESUMO

In the present investigation, we have employed heme as a material for absorbing haloarenes due to its unique structural property, abundant availability, non-toxic nature and its dynamic nature in absorbing oxygen molecule. Haloarenes are toxic gases that are released into atmosphere as an aftermath of various refrigerants. Using first principle study, the absorption of haloarenes on heme molecule was systematically investigated. Fluorine, Chlorine, Bromine and Iodine substituted Haloarenes were allowed to interact with heme molecule with metal ion at +2, +3 and + 4 oxidation states of both low and high spin states. The TD-DFT analysis shows that the heme is a better absorbent at +3 and + 4 oxidation states of Fe ion at low spin state. Among the haloarenes, the interaction energy between IHA and Fe ion at +4 state is maximum with -1.877 eV. The HOMO-LUMO band gap decreases with increase in oxidation state and the orbital delocalization is maximum for high oxidation state. The delocalization of these electronic orbitals shows the active interaction between the heme molecule and haloarene which was confirmed by the DOS plot and the LP to LP* transition in NBO analysis. The absorbing nature of heme was further extended to hexahaloarenes, where heme still stand as a strong absorbing candidate for these toxic gases. The detailed study of the interaction between heme and haloarenes showed that heme at low spin state and with both +3 and + 4 oxidation states can be employed as an absorbent for Haloarenes. Graphical abstract.


Assuntos
Adsorção/efeitos dos fármacos , Gases/química , Heme/química , Termodinâmica , Animais , Bromo/química , Cloro/química , Elétrons , Flúor/química , Gases/toxicidade , Heme/metabolismo , Humanos , Imidazóis/química , Iodo/química , Íons/química , Ferro/química , Modelos Moleculares , Oxirredução/efeitos dos fármacos , Oxigênio/química , Oxigênio/metabolismo
11.
Org Biomol Chem ; 17(47): 10097-10102, 2019 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-31754683

RESUMO

New open-chain and water-soluble hypervalent iodine reagents were synthesized and used for the transfer of fluoroalkyl groups to sulfur atoms of cysteine and cysteine-containing peptides under biocompatible conditions. Some of the reagents displayed excellent reactivity despite their limited stability in aqueous media. In reactions with a short cysteine-containing peptide, in addition to the expected S-fluoroalkylated product, a range of side-products were obtained. The amount of side-products depended on the conditions used (type of reagent, concentration, and pH). With highly activated hypervalent iodine reagents, a new reactive mode was observed - reaction with disulfides to form fluoroalkyl thiols.


Assuntos
Hidrocarbonetos Fluorados/química , Hidrocarbonetos Fluorados/síntese química , Indicadores e Reagentes/química , Indicadores e Reagentes/síntese química , Iodo/química , Compostos de Sulfidrila/química , Água/química , Alquilação , Estrutura Molecular , Solubilidade
12.
Clin Nucl Med ; 44(12): 929-935, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31689274

RESUMO

PURPOSE: The aim of this study was to assess the value of intravenously contrast-enhanced CT in conjunction with Tc-MIBI SPECT for preoperative localization of parathyroid adenoma. METHODS: One hundred ninety-two patients with primary hyperparathyroidism were enrolled in the study between May 2015 and May 2017. The patients underwent a preoperative "one-stop shop" examination with Tc-MIBI SPECT/CT by using dual time-point (10 and 90 minutes) protocol and both nonenhanced CT and contrast-enhanced CT acquisition in the arterial and venous phase, 35 and 75 seconds, respectively, after contrast medium injection start. For 149 patients, the imaging results could be correlated to those at surgery and histopathology. RESULTS: The median adenoma weight was 330 mg. The addition of contrast-enhanced CT increased the sensitivity from 81.1% to 89.9% (P = 0.003). The specificity of nonenhanced SPECT/CT was similar to contrast-enhanced CT (96.1% vs 97.9%; P = 0.077). For patients with uniglandular disease (n = 140, 94.0%), the sensitivity increased from 86.4% to 93.6% (P = 0.021) and the specificity from 96.2% to 97.9% (P = 0.118) by adding contrast-enhanced CT. In patients with multiglandular disease (n = 9, 6.0%), adding contrast-enhanced CT improved detection sensitivity from 42.1% to 63.2%. However, these patients were few and significance was not reached (P = 0.125). CONCLUSIONS: In this cohort, with generally small parathyroid adenomas, the sensitivity in preoperative localization was greatly improved by adding contrast-enhanced CT to Tc-MIBI SPECT/CT.


Assuntos
Adenoma/diagnóstico por imagem , Meios de Contraste/química , Iodo/química , Neoplasias das Paratireoides/diagnóstico por imagem , Período Pré-Operatório , Tomografia Computadorizada com Tomografia Computadorizada de Emissão de Fóton Único/métodos , Adenoma/patologia , Adenoma/cirurgia , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias das Paratireoides/patologia , Neoplasias das Paratireoides/cirurgia , Sensibilidade e Especificidade , Tecnécio Tc 99m Sestamibi , Carga Tumoral
13.
Chem Pharm Bull (Tokyo) ; 67(9): 1015-1018, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31474724

RESUMO

Thiocyanation of aromatic compounds has been investigated using the combination of 1-chloro-1,2-benziodoxol-3-(1H)-one (1) and (trimethylsilyl)isothiocyanate (TMSNCS). The reaction with electron rich aromatic compounds proceeded smoothly to provide the thiocyanated products in high yield, while electron deficient heteroaromatic compounds were not suitable for this reaction. In these reactions, the regioselectivity was generally high. Transformations of the products were also investigated to demonstrate the utility of the reaction. Based on NMR experiments, we propose that thiocyanogen chloride is generated in situ as an active species.


Assuntos
Derivados de Benzeno/química , Compostos Heterocíclicos/química , Isotiocianatos/química , Compostos de Trimetilsilil/química , Iodo/química , Estereoisomerismo
14.
Indian J Public Health ; 63(3): 199-202, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31552848

RESUMO

Background: Iodine deficiency is one of the most prevalent micronutrient deficiencies globally. Women in reproductive age group are vulnerable to develop iodine deficiency as there is an increase in demand for iodine, especially during pregnancy. Objectives: The objective is to assess the prevalence of goiter and its association with iodine status and salt usage practices among the women of reproductive age group. Methods: A community-based cross-sectional study was conducted from August 2015 to July 2017 among 1500 women of reproductive age group in five villages of Udupi Taluk. Stratified sampling design and proportion to population size of the reproductive age women in the study area was used to select the study participants. A pretested semi-structured questionnaire was used for data collection. Goiter was assessed clinically and graded as per the recommended criteria of the WHO. Salt samples from every household were collected for iodine estimation. Blood and urine samples were collected from subsample to estimate thyroid-stimulating hormone levels and urinary iodine excretion levels, respectively. Results: The overall prevalence of goiter was 13% with 11.5% being Grade 1 and 1.5% being Grade 2. No significant association of goiter with urinary iodine, salt iodine levels, and salt usage practices was found. Conclusions: Median urinary iodine among the women with goiter indicates iodine sufficiency and no significant difference observed in urinary iodine levels between women with and without goiter.


Assuntos
Bócio/epidemiologia , Bócio/urina , Iodo/deficiência , Cloreto de Sódio/química , Adolescente , Adulto , Estudos Transversais , Feminino , Humanos , Índia/epidemiologia , Iodo/química , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Cloreto de Sódio na Dieta , Tireotropina/sangue , Adulto Jovem
15.
J Food Sci ; 84(9): 2499-2506, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31393020

RESUMO

As many of the maternal and child health complications result from folic acid, iron, and iodine deficiencies; it makes sense to combat these simultaneously. We have developed cost-effective technology to deliver these three micronutrients simultaneously through salt. Our goal was to retain at least 70% of the micronutrients during 6 months of storage. The fortified salt was formulated by spraying a solution that contained 2% iodine and 0.5% or 1% folic acid onto salt and adding encapsulated ferrous fumarate. The formulated triple fortified salt contained 1,000 ppm iron, 50 ppm iodine, and 12.5 or 25 ppm folic acid. The spray solution and the salt were stored for 2 and 6 months respectively at 25, 35, and 45 °C 60 to 70% relative humidity. Even at 45 °C, over 70% of both iodine and folic acid were retained in the salt. The best formulation based on the color of the salt and stability of iodine and folic acid contained 12.5 ppm folic acid, 50 ppm iodine, and 1,000 ppm iron. These results indicate that iron, iodine, and folic acid can be simultaneously delivered to a vulnerable population through salt using the technology described. Also, the quality control of the process can be developed around pteroic acid that was detected as a primary degradation product of folic acid. PRACTICAL APPLICATION: The technology developed is already transferred to India for industrial scale up. When fully operational, the technology will simultaneously solve iron, iodine, and folic acid deficiencies in vulnerable populations at a very low cost.


Assuntos
Composição de Medicamentos/métodos , Compostos Ferrosos/química , Ácido Fólico/química , Iodo/química , Cloreto de Sódio/química , Composição de Medicamentos/economia , Estabilidade de Medicamentos , Alimentos Fortificados/análise , Alimentos Fortificados/economia , Índia , Micronutrientes/química
16.
Environ Sci Pollut Res Int ; 26(28): 28871-28883, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31385253

RESUMO

The iodine-doped bismuth oxychloride (I-doped BiOCl) microspheres are synthesized as the visible light photocatalysts for the photocatalytic removal of three toxic hydroxyl-contained intermediates of parabens. With the aid of the unique heating mode of microwave method, the I-doped BiOCl photocatalysts with tunable iodine contents and dispersed energy bands, instead of a mixture of BiOI and BiOCl or solid solution, are synthesized under the controllable conditions. Due to the stretched architectures, high specific surface area, and effective separation of photogenerated carriers, they exhibit high activity to the photocatalytic degradation of methyl 2,4-dihydroxybenzoate (MDB), methyl 3,4-dihydroxybenzoate (MDHB), and ethyl 2,4-dihydroxybenzoate (EDB). As a typical result, it is indicated that though MDB as the most difficult intermediate of parabens to be degraded, a 91.2% removal ratio can still be achieved over the I-doped BiOCl with an energy band of 2.79 eV within 60 min. In addition, it is also confirmed that these photocatalysts remain stable throughout the photocatalytic reaction and can be reused, and more importantly, the photogenerated h+ and •O2- are the key reactive species, while •OH plays a negligible role in the photocatalytic reaction. Resorcinol was identified as the main photodegraded intermediate. These results demonstrate that this photocatalytic system not only exhibit a high efficiency but also avoid the consequent secondary pollutions due to the no formation of complex hydroxyl derivatives.


Assuntos
Bismuto/química , Radical Hidroxila/toxicidade , Iodo/química , Parabenos/química , Catálise , Radical Hidroxila/química , Luz , Microesferas , Micro-Ondas , Fotólise
17.
Mikrochim Acta ; 186(8): 565, 2019 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-31338677

RESUMO

A colorimetric and visual assay is described for the herbicide aminotriazole (ATZ). It is based on the etching of gold nanorods (AuNRs) by iodine which is formed on oxidation of iodide via H2O2. Longitudinal etching of the AuNRs occurs quickly and is accompanied by a color change from dark blue to red. In the absence of ATZ and the presence of active catalase (CAT), H2O2 is quickly decomposed into water, and the AuNRs will not be etched. In the presence of ATZ, CAT is partially deactivated, and this affects the amount of available H2O2 and, consequently, of the iodine. Hence, the color is significantly changed. The color changes can be easily detected with bare eyes. The assay has a linear response in the 5 to 70 µM concentration range, with a detection limit of 1.3 µM and high selectivity for ATZ. It was applied to the determination of ATZ in water and food samples. Graphical abstract A multicolor colorimetric method is developed for aminotriazole (ATZ) detection based on catalase (CAT) deactivation-dependent longitudinal etching of gold nanorods (AuNRs). The color signals can be visually identified. Good detection performances and capability for evaluating ATZ level in water and food samples is demonstrated.


Assuntos
Amitrol (Herbicida)/análise , Catalase/metabolismo , Colorimetria/métodos , Nanotubos/química , Cor , Contaminação de Alimentos/análise , Ouro/química , Herbicidas/análise , Peróxido de Hidrogênio/química , Iodo/química , Limite de Detecção , Poluentes Químicos da Água/análise
18.
Anticancer Agents Med Chem ; 19(13): 1627-1632, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31284874

RESUMO

BACKGROUND: There is some evidence that Benign Prostatic Hyperplasia (BPH) may increase the risk of developing prostate cancer, so conducting research on effective BPH inhibitors is important. OBJECTIVE: This research studied the inhibitory effect of Iodized Serum Milk Protein (ISMP) on BPH in rats. ISMP is a concentrate of lactic protein containing 2.2% iodine. METHODS: Male Wistar rats, aged 18 months, were used. In the intact control group, sunflower oil was administered intragastrically by gavage. In 36 rats, BPH was induced by surgical castration, followed by subcutaneous injections of prolonged testosterone - omnadren, 25mg/kg every other day (7 administrations). One group of rats served as BPH-control. ISMP and finasteride (positive control), dissolved in sunflower oil, were administered to rats intragastrically daily at a dose of 200µg/kg and 5mg/kg, respectively, for 4 weeks starting immediately after castration. RESULTS: ISMP inhibited the development of BPH in rats, significantly reducing the mass of the prostate and its parts (except for the anterior lobes) by 1.1-1.3 times and the prostatic index (the ratio of prostate weight to the body weight) - by 1.3-1.4 times. Finasteride inhibited the development of BPH, and its activity was higher (by 1.1-1.3 times) than in ISMP. Histological analysis of the prostate showed fewer pronounced morphological hyperplasia signs in animals treated with ISMP or finasteride. CONCLUSION: The iodine-containing preparation ISMP has the ability to inhibit the development of BPH in rats although its activity is somewhat lower than that of finasteride.


Assuntos
Iodo/química , Proteínas do Leite/química , Hiperplasia Prostática/prevenção & controle , Antagonistas de Androgênios/administração & dosagem , Animais , Finasterida/administração & dosagem , Masculino , Proteínas do Leite/administração & dosagem , Ratos , Ratos Wistar
19.
Environ Sci Pollut Res Int ; 26(23): 23850-23860, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31214887

RESUMO

The environmental fate of iodine is of general geochemical interest as well as of substantial concern in the context of nuclear waste repositories and reprocessing plants. Soils, and in particular soil organic matter (SOM), are known to play a major role in retaining and storing iodine. Therefore, we investigated iodide and iodate sorption by four different reference soils for contact times up to 30 days. Selective sequential extractions and X-ray absorption spectroscopy (XAS) were used to characterize binding behavior to different soil components, and the oxidation state and local structure of iodine. For iodide, sorption was fast with 73 to 96% being sorbed within the first 24 h, whereas iodate sorption increased from 11-41% to 62-85% after 30 days. The organic fraction contained most of the adsorbed iodide and iodate. XAS revealed a rapid change of iodide into organically bound iodine when exposed to soil, while iodate did not change its speciation. Migration behavior of both iodine species has to be considered as iodide appears to be the less mobile species due to fast binding to SOM, but with the potential risk of mobilization when oxidized to iodate.


Assuntos
Iodatos/química , Iodo/química , Solo/química , Adsorção , Iodetos/química , Oxirredução , Espectroscopia por Absorção de Raios X
20.
Phys Med ; 63: 1-6, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31221400

RESUMO

PURPOSE: Polymer gel dosimeters provide three-dimensional absorbed dose information and have gradually become a popular tool for quality assurance in radiotherapy. This study aims to incorporate iodine into the MAGAT-based gel as radiation sensitizer and investigate whether it can be used to measure the radiation dose and slice thickness for CT scans. METHODS: The nMAGAT(I) gel was doped with 0.03, 0.05, and 0.07-M iodine. The absorbed dose was delivered using a CT scanner (Alexion 16, Toshiba Medical Systems, Japan) with tube voltages of 80, 100, 120, and 135 kVp. The irradiated nMAGAT(I) gel was read using a cone beam optical CT scanner to produce dose-response curves. The nMAGAT(I) gel was used to obtain the slice sensitivity profile (SSP) and the CT dose index (CTDI) for quality assurance of CT scans. RESULTS: The 0.07-M iodine-doped nMAGAT(I) gel exhibited maximum sensitivity with the dose enhancement ratio of 2.12. The gel was chemically stable 24 h after its preparation, and the polymerization process was completed 24-48 h after the irradiation. For CT quality assurance, the full width at half maximum measured by the nMAGAT(I) gel matched the nominal slice thickness of CT. The CTDI at center, CTDI at peripheral, and weighted CTDI obtained by the nMAGAT(I) gel differed from those obtained by the ionization chamber by -4.2%, 3.1%, and 0.7%, respectively. CONCLUSIONS: The nMAGAT(I) gel can be used to assess radiation doses and slice thickness in CT scans, thus rendering it a potential quality assurance tool for CT and other radiological diagnostic applications.


Assuntos
Iodo/química , Polimetil Metacrilato/química , Dosímetros de Radiação , Tomografia Computadorizada por Raios X/instrumentação , Géis , Imagens de Fantasmas
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