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1.
Clin Proteomics ; 20(1): 54, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38017382

RESUMO

BACKGROUND: This study investigates the proteomic landscapes of chromophobe renal cell carcinoma (chRCC) and renal oncocytomas (RO), two subtypes of renal cell carcinoma that together account for approximately 10% of all renal tumors. Despite their histological similarities and shared origins, chRCC is a malignant tumor necessitating aggressive intervention, while RO, a benign growth, is often subject to overtreatment due to difficulties in accurate differentiation. METHODS: We conducted a label-free quantitative proteomic analysis on solid biopsies of chRCC (n = 5), RO (n = 5), and normal adjacent tissue (NAT, n = 5). The quantitative analysis was carried out by comparing protein abundances between tumor and NAT specimens. Our analysis identified a total of 1610 proteins across all samples, with 1379 (85.7%) of these proteins quantified in at least seven out of ten LC‒MS/MS runs for one renal tissue type (chRCC, RO, or NAT). RESULTS: Our findings revealed significant similarities in the dysregulation of key metabolic pathways, including carbohydrate, lipid, and amino acid metabolism, in both chRCC and RO. Compared to NAT, both chRCC and RO showed a marked downregulation in gluconeogenesis proteins, but a significant upregulation of proteins integral to the citrate cycle. Interestingly, we observed a distinct divergence in the oxidative phosphorylation pathway, with RO showing a significant increase in the number and degree of alterations in proteins, surpassing that observed in chRCC. CONCLUSIONS: This study underscores the value of integrating high-resolution mass spectrometry protein quantification to effectively characterize and differentiate the proteomic landscapes of solid tumor biopsies diagnosed as chRCC and RO. The insights gained from this research offer valuable information for enhancing our understanding of these conditions and may aid in the development of improved diagnostic and therapeutic strategies.

2.
Chem Rev ; 121(20): 12966-13010, 2021 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-34370446

RESUMO

The use of liquid crystals for the fabrication of displays incorporated in technological devices (TVs, calculators, screens of eBook's, tablets, watches) demonstrates the relevance that these materials have had in our way of living. However, society evolves, and improved devices are looked for as we create a more efficient and safe technology. In this context, metallomesogens can behave as multifunctional materials because they can combine the fluidic state of the mesophases with properties such as photo and electroluminescence, which offers new exciting possibilities in the field of optoelectronics, energy, environment, and even biomedicine. Herein, it has been established the role of the molecular geometry induced by the metal center in metallomesogens to achieve the self-assembly required in the liquid-crystalline mesophase. Likewise, the effect of the coordination environment in metallomesogens has been further analyzed because of its importance to induce mesomorphism. The structural analysis has been combined with an in-depth discussion of the properties of these materials, including their current and potential future applications. This review will provide a solid background to stimulate the development of novel and attractive metallomesogens that allow designing improved optoelectronic and microelectronic components. Additionally, nanoscience and nanotechnology could be used as a tool to approach the design of nanosystems based on luminescent metallomesogens for use in bioimaging or drug delivery.


Assuntos
Cristais Líquidos , Luminescência , Sistemas de Liberação de Medicamentos , Cristais Líquidos/química , Metais , Nanotecnologia
3.
J Fluoresc ; 33(3): 799-847, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36576681

RESUMO

Fluorescent organic dyes play an essential role in the creation of new "smart" materials. Fragments and functional groups capable of free rotation around single bonds can significantly change the fluorescent organic dye's electronic structure under analyte effects, phase state transitions, or changes in temperature, pressure, and media polarity. Dependencies between steric and electronic structures become highly important in transition from a solution to a solid-state. Such transitions are accompanied by a significant increase in the dye molecular structure's rigidity due to supramolecular associates' formation such as H-bonding, π···π and dipole-dipole interactions. Among those supramolecular effects, H-bonding interactions, first of all, lead to significant molecular packing changes between loose or rigid structures, thus affecting the fluorescent dye's electronic states' energy and configuration, its fluorescent signal's position and intensity. All the functional groups and heteroatoms that are met in the organic dyes seem to be involved in the control of fluorescence via H-bonding: C-H···N, C-H···π, S = O···H-C, P = O···H, C-H···O, NH···N, C - H···C, C - H···Se, N-H···O, C - H···F, C-F···H. Effects of molecular packing of fluorescent organic dyes are successfully used in developing mechano-, piezo-, thermo- fluorochromes materials for their applications in the optical recording of information, sensors, security items, memory elements, organic light-emitting diodes (OLEDs) technologies.

4.
Sensors (Basel) ; 23(3)2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36772728

RESUMO

Three coumarin-based boron complexes (L1, L2 and L3) were designed and successfully incorporated into polymeric matrixes for evaluation as temperature probes. The photophysical properties of the complexes were carried out in different solvents and in the solid state. In solution, compound L1 exhibited the highest fluorescence quantum yield, 33%, with a positive solvatochromism also being observed on the absorption and emission when the polarity of the solvent increased. Additionally in the presence of anions, L1 showed a colour change from yellow to pink, followed by a quenching in the emission intensity, which is due to deprotonation with the formation of a quinone base. Absorption and fluorescence spectra of L1 were calculated at different temperatures by the DFT/B3LYP method. The decrease in fluorescence of compound L1 with an increase in temperature seems to be due to the presence of pronounced torsional vibrations of the donor and acceptor fragments relative to the single bond with C(carbonyl)-C (styrene fragment). L1, L2 and L3, through their incorporation into the polymeric matrixes, became highly emissive by aggregation. These dye@doped polymers were evaluated as temperature sensors, showing an excellent fluorescent response and reversibility after 15 cycles of heating and cooling.

5.
Int J Mol Sci ; 24(7)2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37047582

RESUMO

The need for non-invasive therapies capable of conserving drug efficiency and stability while having specific targetability against colorectal cancer (CRC), has made nanoparticles preferable vehicles and principal building blocks for the development of complex and multi-action anti-tumoral approaches. For that purpose, we herein report the production of a combinatory anti-tumoral nanotherapy using the production of a new targeting towards CRC lines. To do so, Magneto-fluorescent NANO3 nanoparticles were used as nanocarriers for a combination of the drugs doxorubicin (DOX) and ofloxacin (OFLO). NANO3 nanoparticles' surface was modified with two different targeting agents, a newly synthesized (anti-CA IX acetazolamide derivative (AZM-SH)) and a commercially available (anti-epidermal growth factor receptor (EGFR), Cetuximab). The cytotoxicity revealed that only DOX-containing nanosystems showed significant and even competitive cytotoxicity when compared to that of free DOX. Interestingly, surface modification with AZM-SH promoted an increased cellular uptake in the HCT116 cell line, surpassing even those functionalized with Cetuximab. The results show that the new target has high potential to be used as a nanotherapy agent for CRC cells, surpassing commercial targets. As a proof-of-concept, an oral administration form of NANO3 systems was successfully combined with Eudragit® enteric coating and studied under extreme conditions.


Assuntos
Neoplasias Colorretais , Nanopartículas , Humanos , Cetuximab/uso terapêutico , Linhagem Celular Tumoral , Doxorrubicina/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Sistemas de Liberação de Medicamentos/métodos
6.
Int J Mol Sci ; 23(20)2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36293142

RESUMO

Cancer-related opportunistic bacterial infections are one major barrier for successful clinical therapies, often correlated to the production of genotoxic factors and higher cancer incidence. Although dual anticancer and antimicrobial therapies are a growing therapeutic fashion, they still fall short when it comes to specific delivery and local action in in vivo systems. Nanoparticles are seen as potential therapeutic vectors, be it by means of their intrinsic antibacterial properties and effective delivery capacity, or by means of their repeatedly reported modulation and maneuverability. Herein we report on the production of a biocompatible, antimicrobial magneto-fluorescent nanosystem (NANO3) for the delivery of a dual doxorubicin-ofloxacin formulation against cancer-related bacterial infections. The drug delivery capacity, rendered by its mesoporous silica matrix, is confirmed by the high loading capacity and stimuli-driven release of both drugs, with preference for tumor-like acidic media. The pH-dependent emission of its surface fluorescent SiQDs, provides an insight into NANO3 surface behavior and pore availability, with the SiQDs working as pore gates. Hyperthermia induces heat generation to febrile temperatures, doubling drug release. NANO3-loaded systems demonstrate significant antimicrobial activity, specifically after the application of hyperthermia conditions. NANO3 structure and antimicrobial properties confirm their potential use in a future dual anticancer and antimicrobial therapeutical vector, due to their drug loading capacity and their surface availability for further modification with bioactive, targeting species.


Assuntos
Anti-Infecciosos , Neoplasias Colorretais , Hipertermia Induzida , Nanopartículas , Humanos , Portadores de Fármacos/química , Ofloxacino , Porosidade , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Doxorrubicina/química , Dióxido de Silício/química , Nanopartículas/química , Liberação Controlada de Fármacos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Anti-Infecciosos/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Sistemas de Liberação de Medicamentos
7.
Int J Mol Sci ; 23(14)2022 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-35886956

RESUMO

An efficient synthetic access to new cationic porphyrin-bipyridine iridium(III) bis-cyclometalated complexes was developed. These porphyrins bearing arylbipyridine moieties at ß-pyrrolic positions coordinated with iridium(III), and the corresponding Zn(II) porphyrin complexes were spectroscopically, electrochemically, and electronically characterized. The features displayed by the new cyclometalated porphyrin-bipyridine iridium(III) complexes, namely photoinduced electron transfer process (PET), and a remarkable efficiency to generate 1O2, allowing us to envisage new challenges and opportunities for their applications in several fields, such as photo(catalysis) and photodynamic therapies.


Assuntos
Irídio , Porfirinas , Cátions , Transporte de Elétrons , Irídio/química , Ligantes
8.
BMC Med ; 19(1): 196, 2021 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-34482820

RESUMO

BACKGROUND: Renal neoplasms encompass a variety of malignant and benign tumors, including many with shared characteristics. The diagnosis of these renal neoplasms remains challenging with currently available tools. In this work, we demonstrate the total protein approach (TPA) based on high-resolution mass spectrometry (MS) as a tool to improve the accuracy of renal neoplasm diagnosis. METHODS: Frozen tissue biopsies of human renal tissues [clear cell renal cell carcinoma (n = 7), papillary renal cell carcinoma (n = 5), chromophobe renal cell carcinoma (n = 5), and renal oncocytoma (n = 5)] were collected for proteome analysis. Normal adjacent renal tissue (NAT, n = 5) was used as a control. Proteins were extracted and digested using trypsin, and the digested proteomes were analyzed by label-free high-resolution MS (nanoLC-ESI-HR-MS/MS). Quantitative analysis was performed by comparison between protein abundances of tumors and NAT specimens, and the label-free and standard-free TPA was used to obtain absolute protein concentrations. RESULTS: A total of 205 differentially expressed proteins with the potential to distinguish the renal neoplasms were found. Of these proteins, a TPA-based panel of 24, including known and new biomarkers, was selected as the best candidates to differentiate the neoplasms. As proof of concept, the diagnostic potential of PLIN2, TUBB3, LAMP1, and HK1 was validated using semi-quantitative immunohistochemistry with a total of 128 samples assessed on tissue micro-arrays. CONCLUSIONS: We demonstrate the utility of combining high-resolution MS and the TPA as potential new diagnostic tool in the pathology of renal neoplasms. A similar TPA approach may be implemented in any cancer study with solid biopsies.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Biomarcadores Tumorais , Carcinoma de Células Renais/diagnóstico , Diagnóstico Diferencial , Humanos , Neoplasias Renais/diagnóstico , Proteômica , Espectrometria de Massas em Tandem
9.
South Med J ; 114(6): 351-355, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34075427

RESUMO

OBJECTIVES: Refeeding syndrome is a life-threatening, physiological process that occurs when patients with severe malnutrition are too rapidly rehabilitated, leading to the development of electrolyte abnormalities. Hypophosphatemia, a hallmark of the disease, has most commonly been studied, because it is recognized to result in cardiac arrhythmias, seizures, cardiac failure, respiratory failure, rhabdomyolysis, coma, and even death. Although many studies have found caloric intake to be a main causal factor in refeeding syndrome, few have explored other factors, such as geographic location. Border cities, such as El Paso, Texas, have a unique, diverse population. The purpose of this study was to establish the incidence of refeeding syndrome concentrated within a border city. METHODS: We performed a retrospective chart review that focused on the incidence of refeeding syndrome in pediatric patients with eating disorders, ages 10 to 19 years, admitted to El Paso Children's Hospital, the only tertiary teaching hospital in the area, associated with Texas Tech University Health Science Center, located along the US-Mexico border, in El Paso, Texas. RESULTS: Twenty-six subjects with a diagnosis of eating disorder were admitted to El Paso Children's Hospital for treatment between 2012 and 2019. Five subjects developed refeeding syndrome, recognized in our study as hypokalemia or hypomagnesemia, during their treatment. CONCLUSIONS: Among hospitalized adolescents admitted to El Paso Children's Hospital, 19% developed refeeding syndrome. This incidence was higher in our population than had been previously reported. Further research is needed to better establish a protocol for the treatment of patients with eating disorders.


Assuntos
Pediatria/estatística & dados numéricos , Síndrome da Realimentação/diagnóstico , Adolescente , Criança , Emigração e Imigração/estatística & dados numéricos , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Incidência , Masculino , México/epidemiologia , Pediatria/métodos , Síndrome da Realimentação/epidemiologia , Estudos Retrospectivos , Texas/epidemiologia
10.
Anal Chem ; 92(13): 9164-9171, 2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32484334

RESUMO

We propose a new high-throughput ultrafast method for large-scale proteomics approaches by speeding up the classic filter aided sample preparation protocol, FASP, from overnight to 2.5 h. Thirty-six samples can be treated in 2.5 h, and the method is scalable to 96-well plate-based pipelines. After a modification of the FASP-tube, the steps of protein reduction, protein alkylation, and protein digestion of complex proteomes are done in just 5.25 min, each one under the effects of an ultrasonic field (7 cycles: 30 s on and 15 s off). The new method was compared to the standard overnight digestion FASP protocol, and no statistical differences were found for more than 92.4%, 92%, and 93.3% of the proteins identified by studying the proteome of E. coli, mouse brain, and mouse liver tissue samples, respectively. Furthermore, the successful relative label-free quantification of four spiked proteins in E. coli samples, BSA, ß-lactoglobulin, α-casein, and α-lactalbumin, was achieved, using either the ultrasonic-based FASP protocol or the classic overnight one. The new US-FASP method matches the analytical minimalism rules as time, cost, sample requirement, reagent consumption, energy requirements, and production of waste products are reduced to a minimum while maintaining high sample throughput in a robust manner as all of the advantages of the filter aided sample preparation protocol are maintained.


Assuntos
Filtração , Proteoma/análise , Proteômica/métodos , Sonicação , Animais , Encéfalo/metabolismo , Caseínas/análise , Escherichia coli/metabolismo , Proteínas de Escherichia coli/análise , Fígado/metabolismo , Camundongos , Oxirredução
11.
FASEB J ; 33(3): 4610-4625, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30576225

RESUMO

Liver fatty acid binding protein (L-Fabp) modulates lipid trafficking in enterocytes, hepatocytes, and hepatic stellate cells (HSCs). We examined hepatocyte vs. HSC L-Fabp deletion in hepatic metabolic adaptation and fibrotic injury. Floxed L-Fabp mice were bred to different transgenic Cre mice or injected with adeno-associated virus type 8 (AAV8) Cre and fed diets to promote steatosis and fibrosis or were subjected to either bile duct ligation or CCl4 injury. Albumin-Cre-mediated L-Fabp deletion revealed recombination in hepatocytes and HSCs; these findings were confirmed with 2 other floxed alleles. Glial fibrillary acid protein-Cre and platelet-derived growth factor receptor ß-Cre-mediated L-Fabp deletion demonstrated recombination only in HSCs. Mice with albumin promoter-driven Cre recombinase (Alb-Cre)-mediated or AAV8-mediated L-Fabp deletion were protected against food withdrawal-induced steatosis. Mice with Alb-Cre-mediated L-Fabp deletion were protected against high saturated fat-induced steatosis and fibrosis, phenocopying germline L-Fabp-/- mice. Mice with HSC-specific L-Fabp deletion exhibited retinyl ester depletion yet demonstrated no alterations in fibrosis. On the other hand, fibrogenic resolution after CCl4 administration was impaired in mice with Alb-Cre-mediated L-Fabp deletion. These findings suggest cell type-specific roles for L-Fabp in mitigating hepatic steatosis and in modulating fibrogenic injury and reversal.-Newberry, E. P., Xie, Y., Lodeiro, C., Solis, R., Moritz, W., Kennedy, S., Barron, L., Onufer, E., Alpini, G., Zhou, T., Blaner, W. S., Chen, A., Davidson, N. O. Hepatocyte and stellate cell deletion of liver fatty acid binding protein reveal distinct roles in fibrogenic injury.


Assuntos
Intoxicação por Tetracloreto de Carbono/metabolismo , Proteínas de Ligação a Ácido Graxo/fisiologia , Fígado Gorduroso/metabolismo , Células Estreladas do Fígado/metabolismo , Hepatócitos/metabolismo , Cirrose Hepática/metabolismo , Albuminas/genética , Animais , Ductos Biliares , Intoxicação por Tetracloreto de Carbono/patologia , Cruzamentos Genéticos , Dependovirus/genética , Gorduras na Dieta/toxicidade , Proteínas de Ligação a Ácido Graxo/deficiência , Ácidos Graxos/toxicidade , Fígado Gorduroso/etiologia , Fígado Gorduroso/patologia , Feminino , Fibrose , Privação de Alimentos , Deleção de Genes , Genes Sintéticos , Células Estreladas do Fígado/patologia , Hepatócitos/patologia , Integrases , Ligadura , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Especificidade de Órgãos , Regiões Promotoras Genéticas
12.
Surg Endosc ; 34(3): 1261-1269, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31183792

RESUMO

BACKGROUND: Barbed suture has been adopted across all surgical specialties. One of the infrequent complications seen with the use of barbed suture is small bowel obstructions (SBOs). In this study, we perform a review of the literature and the Manufacturer and User Facility Device Experience Database (MAUDE) to characterize SBOs after the use of barbed sutures in a variety of operative procedures. METHODS: A review of the literature was performed by searching PubMed and Ovid. We used the search terms: "barbed," "suture," "bowel," and "obstructions." For each case report, we examined the initial surgical procedure, type of barbed suture used, the type of complication, the time to complication, the presentation, and the type of operative interventions required. We did the same with the MAUDE database. RESULTS: Our review of the literature revealed 18 different cases of SBO secondary to the use of barbed suture. The four most common procedures, with a total of four cases each, were inguinal hernia procedures, myomectomy, hysterectomy, and pelvic floor reconstructive procedures. The average time of presentation to SBO was found to be 26.3 days post-op (1-196 days). A total of 16 patients (88.9%) presented with abdominal pain. Other common complaints included vomiting (33.3%), abdominal distension (27.8%), oral intolerance (22.2%), and constipation (16.7%). A total of 5 cases were also found to have a possible volvulus on computed tomography (CT), and 2 cases were reported to have strangulation. The MAUDE database had 14 cases reporting on obstruction. CONCLUSIONS: Surgeons should have a high index of suspicion for SBO if a patient presents with obstructive symptoms after a surgery that used barbed suture. This will often present as a mesenteric volvulus on CT. These particular SBOs require operative exploration, with laparoscopy being successful in the majority of cases.


Assuntos
Obstrução Intestinal/etiologia , Complicações Pós-Operatórias/etiologia , Suturas/efeitos adversos , Desenho de Equipamento , Feminino , Hérnia Inguinal/cirurgia , Humanos , Histerectomia/efeitos adversos , Volvo Intestinal/diagnóstico por imagem , Volvo Intestinal/etiologia , Intestino Delgado/cirurgia , Laparoscopia , Procedimentos de Cirurgia Plástica/efeitos adversos , Técnicas de Sutura/instrumentação , Miomectomia Uterina/efeitos adversos
13.
Dyes Pigm ; 182: 108660, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32834207

RESUMO

•Special Issue on 4th IC3EM 2020.•Science, Techniques, Surveillance.•The importance of Science.•Fluorescent dyes.

14.
J Proteome Res ; 18(7): 2979-2986, 2019 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-31173681

RESUMO

An effective three-step proteomics workflow is proposed to overcome the pitfalls caused by polymers present in optimum cutting temperature (OCT)-embedded tissue during its preparation for mass spectrometry analysis. First, the OCT-embedded tissue biopsies are cleaned using ethanol and water in a sequential series of ultrasonic washes in an ultrasound bath (35 kHz ultrasonic frequency, 100% ultrasonic amplitude, 2 min of ultrasonic duty time). Second, a fast ultrasonic-assisted extraction of proteins is done using an ultrasonic probe (30 kHz ultrasonic frequency, 50% ultrasonic amplitude, 2 min of ultrasonic duty time, 1 mm diameter tip). Third, a rapid ultrasonic digestion of complex proteomes is performed using a microplate horn assembly device (20 kHz ultrasonic frequency, 25% ultrasonic amplitude, 4 min of ultrasonic duty time). As a proof of concept, the new workflow was applied to human normal and tumor kidney biopsies including chromophobe renal cell carcinomas (chRCCs) and renal oncocytomas (ROs). A successful cluster of proteomics profiles was obtained comprising 511 and 172 unique proteins found in chRCC and RO samples, respectively. The new method provides high sample throughput and comprehensive protein recovery from OCT samples.


Assuntos
Neoplasias/química , Proteoma/análise , Manejo de Espécimes/métodos , Inclusão do Tecido/métodos , Adenoma Oxífilo/química , Biópsia , Carcinoma de Células Renais/química , Humanos , Neoplasias Renais/química , Neoplasias/patologia , Estudo de Prova de Conceito , Espectrometria de Massas em Tandem , Ultrassom
15.
Chemistry ; 25(52): 12046-12051, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31237959

RESUMO

Herein, we report a series of unsymmetrical bispyrazolate-type PtII compounds that exhibit mesomorphism at low temperatures and photophysical multi-stimuli-responsive properties. These PtII compounds show a great ability to be self-assembled by intermolecular Pt⋅⋅⋅Pt interactions in the solid state, so generating a columnar stacking of molecules that is responsible for the formation of the mesophases. By controlling the nature of the molecular assembly through external stimuli such as the temperature, the pressure, or the presence of vapours or solvents, it is possible to modulate the luminescence behaviour of these materials. The PtII monomers emit a greenish light, whereas aggregation of molecules produces a redshifted emission. These metallomesogens also show a high stability and successive grinding/fuming cycles can be performed without degradation of the sample. The application of these materials is very attractive as rewritable luminescent platforms, and their use is already demonstrated.

16.
J Org Chem ; 83(9): 5282-5287, 2018 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-29644855

RESUMO

The synthesis of two triads with two porphyrinyl units linked by oligopyridine derivatives and a new ß-functionalized porphyrin-dihydroazepine is described. One of the porphyrin-oligopyridine triads has a quinquepyridine unit connecting the porphyrins ß-pyrrolic positions, while the other one has an asymmetric quaterpyridine with one of the pyridines fused to the porphyrin. All compounds have fluorescence emission quantum yields in the range of meso-tetraphenylporphyrin (16-22%).

17.
Molecules ; 23(4)2018 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-29642601

RESUMO

In this work, the N-confused porphyrin 5,10,15,20-tetraphenyl-2-aza-21-carbaporphyrin (NCTPP) was immobilized on neutral or cationic supports based on silica and on Merrifield resin. The new materials were characterized by appropriate techniques (UV-Vis spectroscopy, SEM, and zeta potential analysis). Piezoelectric quartz crystal gold electrodes were coated with the different hybrids and their ability to interact with heavy metals was evaluated. The preliminary results obtained showed that the new materials can be explored for metal cations detection and the modification of the material surface is a key factor in tuning the metal selectivity.


Assuntos
Metais Pesados/análise , Porfirinas/química , Técnicas Biossensoriais , Eletrodos , Estrutura Molecular , Poliestirenos/química , Dióxido de Silício/química , Propriedades de Superfície
18.
Chemistry ; 22(29): 10168-78, 2016 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-27273696

RESUMO

New dicatenar isoquinoline-functionalized pyrazoles, [Hpz(R(n,n)iq) ] (R(n,n)=C6 H3 (OCn H2n+1 )2 ; n=4, 6, 8, 10, 12, 14, 16, 18), have been strategically designed and synthesized to induce mesomorphic and luminescence properties into the corresponding bis(isoquinolinylpyrazolate)platinum(II) complexes [Pt(pz(R(n,n)iq) )2 ]. Thermal studies reveal that all platinum(II) compounds exhibit columnar mesophases over an exceptionally wide temperature range, above 300 °C in most cases. The photophysical behavior was also investigated in solution and in the solid state. As a consequence of the formation of Pt⋅⋅⋅Pt interactions, the weak greenish emission of the platinum derivatives turns bright orange in the mesophase. Additionally, the complexes are sensitive to a great variety of external inputs, such as temperature, mechanical grinding, pressure, solvents, and vapors. On this basis, they are used as dopant agents of a polyvinylpyrrolidone or poly(methyl methacrylate) polymer matrix to achieve stimuli-responsive thin films.

19.
Photochem Photobiol Sci ; 14(4): 757-64, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25620620

RESUMO

A metal complex 1 derivative from a coumarin bearing a porphyrin unit was spectroscopically characterized and its sensing ability towards the alkaloids caffeine 2, nicotine 3 and cotinine 4 was evaluated in these studies. This probe shows to be sensitive to the alkaloids studied, where a detectable amount of 2.5 ± 0.3 µM of cotinine was determined in dam water from the Vigia Dam located in the Montoito village region, Alentejo district, Portugal. The interaction of 1 with cotinine was also verified by MALDI-TOF-MS, where it was found with peaks at 877.2 and 1053.3 m/z corresponding to the species [1H](+) and [1CotinineH](+), respectively.


Assuntos
Cafeína/química , Cotinina/química , Cumarínicos/química , Água Doce/química , Nicotina/química , Porfirinas/química , Zinco/química , Etanol/química , Estrutura Molecular , Processos Fotoquímicos , Portugal , Soluções , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Análise Espectral , Raios Ultravioleta
20.
Clin Proteomics ; 11(1): 17, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24742231

RESUMO

BACKGROUND: Peritoneal dialysis (PD) is a form of renal replacement used for advanced chronic kidney disease. PD effluent holds a great potential for biomarker discovery for diagnosis and prognosis. In this study a novel approach to unravelling the proteome of PD effluent based-on dithiothreitol depletion followed by 2D-SDS-PAGE and protein identification using tandem mass spectrometry is proposed. RESULTS: A total of 49 spots were analysed revealing 25 proteins differentially expressed, among them many proteins involved in calcium regulation. CONCLUSIONS: Remarkably, a group of proteins dealing with calcium metabolism and calcium regulation has been found to be lost through peritoneal dialysate effluent, giving thus a potential explanation to the calcification of soft tissues in patients subjected to peritoneal dialysis and kidney injury. Comparison of literature dealing with PD is difficult due to differences in sample treatment and analytical methodologies.

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