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1.
Biosens Bioelectron ; 145: 111718, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31561094

RESUMO

Taking advantage of surface-enhanced Raman scattering (SERS) methodology with its unique ability to collect abundant intrinsic fingerprint information and noninvasive data acquisition we set up a SERS-based approach for recognition of physically induced DNA damage with further incorporation of artificial neural network (ANN). As a proof-of-concept application, we used the DNA molecules, where the one oligonucleotide (OND) was grafted to the plasmonic surface while complimentary OND was exposed to UV illumination with various exposure doses and further hybridized with the grafted counterpart. All SERS spectra of entrapped DNA were collected by several operators using the portable spectrometer, without any optimization of measurements procedure (e.g., optimization of acquisition time, laser intensity, finding of optimal place on substrate, manual baseline correction, etc.) which usually takes a significant amount of operator's time. The SERS spectra were employed as input data for ANN training, and the performance of the system was verified by predicting the class labels for SERS validation data, using a spectra dataset, which has not been involved in the training process. During that phase, accuracy higher than 98% was achieved with a level of confidence exceeding 95%. It should be noted that utilization of the proposed functional-SERS/ANN approach allows identifying even the minor DNA damage, almost invisible by control measurements, performed with common analytical procedures. Moreover, we introduce the advanced ANN design, which allows not only classifying the samples but also providing the ANN analysis feedback, which associates the spectral changes and chemical transformations of DNA structure.


Assuntos
Técnicas Biossensoriais , Dano ao DNA , DNA/isolamento & purificação , Análise Espectral Raman , DNA/química , Ouro/química , Nanopartículas Metálicas/química , Redes Neurais de Computação , Oligonucleotídeos/química
2.
Int J Obes (Lond) ; 39(6): 986-93, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25771926

RESUMO

OBJECTIVES: Obesity is a frequent metabolic disorder but an effective therapy is still scarce. Anorexigenic neuropeptides produced and acting in the brain have the potential to decrease food intake and ameliorate obesity but are ineffective after peripheral application. We have designed lipidized analogs of prolactin-releasing peptide (PrRP), which is involved in energy balance regulation as demonstrated by obesity phenotypes of both PrRP- and PrRP-receptor-knockout mice. RESULTS: Lipidized PrRP analogs showed binding affinity and signaling in PrRP receptor-expressing cells similar to natural PrRP. Moreover, these analogs showed high binding affinity also to anorexigenic neuropeptide FF-2 receptor. Peripheral administration of myristoylated and palmitoylated PrRP analogs to fasted mice induced strong and long-lasting anorexigenic effects and neuronal activation in the brain areas involved in food intake regulation. Two-week-long subcutaneous administration of palmitoylated PrRP31 and myristoylated PrRP20 lowered food intake, body weight and improved metabolic parameters, and attenuated lipogenesis in mice with diet-induced obesity. CONCLUSIONS: Our data suggest that the lipidization of PrRP enhances stability and mediates its effect in central nervous system. Strong anorexigenic and body-weight-reducing effects make lipidized PrRP an attractive candidate for anti-obesity treatment.


Assuntos
Fármacos Antiobesidade/farmacologia , Lipídeos/química , Obesidade/prevenção & controle , Hormônio Liberador de Prolactina/farmacologia , Animais , Regulação do Apetite , Ingestão de Alimentos , Metabolismo Energético , Meia-Vida , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Hormônio Liberador de Prolactina/análogos & derivados , Transdução de Sinais
3.
Mol Cell Endocrinol ; 393(1-2): 120-8, 2014 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-24953973

RESUMO

The only peripherally released orexigenic hormone, ghrelin, plays a key role in food intake and body weight regulation. Antagonizing the ghrelin receptor, GHS-R1a, represents a promising approach for anti-obesity therapy. In our study, two novel GHS-R1a antagonists JMV4208 and JMV3002, which are trisubstituted 1,2,4-triazoles, decreased food intake in fasted lean mice in a dose-dependent manner, with ED50 values of 5.25 and 2.05 mg/kg, respectively. Both compounds were stable in mouse blood, with half-lives of 90 min (JMV4208) and 60 min (JMV3002), and disappeared from the blood 8h after administration. Fourteen days of treatment with the ghrelin antagonists (20 mg/kg twice a day) decreased food intake, body weight and adipose tissue mass in mice with diet-induced obesity (DIO). These results are likely attributable to an impact on food intake reduction and an attenuated expression of the lipogenesis-promoting enzymes (acetyl-CoA carboxylase 1 in subcutaneous fat and fatty acid synthase in subcutaneous and intraperitoneal fat). The decrease in fat mass negatively impacted circulating leptin levels. These data suggest that JMV4208 and JMV3002 could be useful therapeutic agents for the treatment of obesity.


Assuntos
Tecido Adiposo/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Ingestão de Alimentos/efeitos dos fármacos , Ácidos Picolínicos/farmacologia , Receptores de Grelina/antagonistas & inibidores , Triazóis/farmacologia , Animais , Relação Dose-Resposta a Droga , Camundongos , Camundongos Endogâmicos C57BL , Ácidos Picolínicos/química , Triazóis/química
4.
Physiol Res ; 62(4): 435-44, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23590608

RESUMO

Ghrelin and agonists of its receptor GHS-R1a are potential substances for the treatment of cachexia. In the present study, we investigated the acute and long term effects of the GHS R1a agonist JMV 1843 (H Aib-DTrp-D-gTrp-CHO) on food intake, body weight and metabolic parameters in lean C57BL/6 male mice. Additionally, we examined stability of JMV 1843 in mouse blood serum. A single subcutaneous injection of JMV 1843 (0.01-10 mg/kg) increased food intake in fed mice in a dose-dependent manner, up to 5-times relative to the saline-treated group (ED(50)=1.94 mg/kg at 250 min). JMV 1843 was stable in mouse serum in vitro for 24 h, but was mostly eliminated from mouse blood after 2 h in vivo. Ten days of treatment with JMV 1843 (subcutaneous administration, 10 or 20 mg/kg/day) significantly increased food intake, body weight and mRNA expression of the orexigenic neuropeptide Y and agouti-related peptide in the medial basal hypothalamus and decreased the expression of uncoupling protein 1 in brown adipose tissue. Our data suggest that JMV 1843 could have possible future uses in the treatment of cachexia.


Assuntos
Proteína Relacionada com Agouti/metabolismo , Estimulantes do Apetite/farmacologia , Ingestão de Alimentos/efeitos dos fármacos , Grelina/agonistas , Hipotálamo/efeitos dos fármacos , Neuropeptídeo Y/metabolismo , Oligopeptídeos/farmacologia , Aumento de Peso/efeitos dos fármacos , Tecido Adiposo Marrom/efeitos dos fármacos , Tecido Adiposo Marrom/metabolismo , Proteína Relacionada com Agouti/genética , Animais , Estimulantes do Apetite/administração & dosagem , Estimulantes do Apetite/farmacocinética , Relação Dose-Resposta a Droga , Grelina/metabolismo , Hipotálamo/metabolismo , Indóis , Injeções Subcutâneas , Canais Iônicos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Mitocondriais/metabolismo , Neuropeptídeo Y/genética , Oligopeptídeos/administração & dosagem , Oligopeptídeos/farmacocinética , RNA Mensageiro/metabolismo , Receptores de Grelina/agonistas , Receptores de Grelina/metabolismo , Transdução de Sinais/efeitos dos fármacos , Triptofano/análogos & derivados , Proteína Desacopladora 1 , Regulação para Cima
5.
Mol Cell Endocrinol ; 343(1-2): 55-62, 2011 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-21704671

RESUMO

It was demonstrated that estrogen deficiency and consuming high fat (HF) diet enhanced orexigenic activity of ghrelin. Therefore, we hypothesized that antagonizing of ghrelin action would attenuate food intake and body weight in mice obese both from ovariectomy (OVX) and feeding a HF diet. Ghrelin receptor antagonist [D-Lys(3)]GHRP-6 after seven days of subcutaneous treatment markedly decreased food intake in OVX mice fed both HF and standard diets; furthermore, it reduced body weight and blood glucose, insulin and leptin, and increased ß-hydroxybutyrate level and uncoupling-protein-1 mRNA in brown adipose tissue. Pair-feeding revealed that effect of [D-Lys(3)]GHRP-6 was primary anorexigenic. Estrogen supplementation reduced anorexigenic effects of [D-Lys(3)]GHRP-6. OVX [D-Lys(3)]GHRP-6 treatment in mice on HF diet resulted in markedly increased circulating level and liver expression of a major metabolic regulator, fibroblast growth factor 21. Our data suggest that ghrelin antagonists could be especially beneficial in individuals with common obesity combined with estrogen deficiency.


Assuntos
Adiposidade/efeitos dos fármacos , Dieta Hiperlipídica , Modelos Animais , Obesidade/fisiopatologia , Oligopeptídeos/farmacologia , Pós-Menopausa/metabolismo , Receptores de Grelina/antagonistas & inibidores , Tecido Adiposo Marrom/metabolismo , Animais , Comportamento Animal/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Ingestão de Alimentos/efeitos dos fármacos , Estrogênios/administração & dosagem , Estrogênios/deficiência , Feminino , Grelina/metabolismo , Transportador de Glucose Tipo 1/genética , Transportador de Glucose Tipo 1/metabolismo , Humanos , Canais Iônicos/genética , Canais Iônicos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Atividade Motora/efeitos dos fármacos , Ovariectomia , PPAR alfa/genética , PPAR alfa/metabolismo , Receptores de Grelina/genética , Receptores de Grelina/metabolismo , Proteína Desacopladora 1
6.
Anal Chim Acta ; 587(2): 247-53, 2007 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-17386780

RESUMO

The ion selective electrode (ISE)-based potentiometric approach is shown to be an effective means of characterizing the anion recognition sites in the molecular receptor calix[2]pyridino[2]pyrrole (CPP). In particular, potentiometric pH-measurements involving the use of experimental PVC-membranes based on CPP revealed the existence of both mono- and diprotonated forms of the receptor under readily accessible conditions. Based on these analyses, apparent surface protonation constants for this heterocalixarene were found to lie between 8.5-8.9 (pK(B1)) and 3.3-3.8 (pK(B2)). CPP was found to interact with targeted anionic analytes based on both coulombic and hydrogen bond interactions, as inferred from varying the kinds of ionic sites present within the membrane phase. Potentiometric selectivity studies revealed that CPP preferred "Y-shaped" anions (e.g. acetate, lactate, benzoate) over spherical anions (e.g. fluoride and chloride), fluoride over chloride within the set of spherical anions, and the ortho-isomer over the corresponding meta- and para-isomers in the case of hydroxybenzoate (salicylate and congeners). In the context of this study, the advantages of potentiometric determinations of acetylsalicylic acid using optimized PVC-membranes based on CPP relative to more conventional PVC-membrane ISEs based on traditional anion exchanger were also demonstrated.


Assuntos
Ânions/química , Calixarenos/química , Técnicas de Química Analítica/métodos , Eletrodos Seletivos de Íons , Potenciometria/métodos , Aspirina/análise , Sítios de Ligação , Ligação de Hidrogênio , Concentração de Íons de Hidrogênio , Íons , Modelos Químicos , Polímeros/química , Ácido Salicílico/química
7.
Eur J Surg Oncol ; 32(4): 450-4, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16546343

RESUMO

AIMS: Controversial issues with respect to the treatment of patients with endometrial cancer include indications for lymphadenectomy and adjuvant radiotherapy. PATIENT AND METHODS: Between 1998 and 2004 all women with endometrial cancer stage I were included (n = 335). They all underwent total abdominal hysterectomy and bilateral salpingo-oöphorectomy. Two hundred and thirty-seven women also had a pelvic lymphadenectomy. When pelvic lymphadenectomy was performed, radiotherapy was administered only to patients with lymph-node metastases. Otherwise, adjuvant radiotherapy was based on the presence of risk factors. RESULTS: Eleven patients had lymph-node metastases. The overall absolute and relative survival-estimate at 5 years was 85.0 and 93.7%, respectively. Loco-regional recurrence was 8.5%. In the group with pelvic lymphadenectomy and negative lymph nodes these rates were 88.2, 93.9 and 5.6%, respectively. In 58 patients without any of the risk factors tumour grade III, deep myometrial invasion, or age > or =60 years, no lymph-node metastases were found. CONCLUSION: In patients with endometrial cancer FIGO stage I without risk-factors, a phenomenon which occurs in about 25% of patients with clinical stage I endometrial cancer, a lymphadenectomy can be omitted. In other patients, the debate regarding the optimal treatment will remain.


Assuntos
Carcinoma/cirurgia , Neoplasias do Endométrio/cirurgia , Excisão de Linfonodo/métodos , Carcinoma/radioterapia , Carcinoma/secundário , Neoplasias do Endométrio/patologia , Neoplasias do Endométrio/radioterapia , Feminino , Humanos , Metástase Linfática , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Pelve , Radioterapia Adjuvante , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
8.
J Chromatogr A ; 887(1-2): 3-29, 2000 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-10961301

RESUMO

Monolithic columns for capillary electrochromatography (CEC) are receiving quite remarkable attention. Both the simplicity of the in situ preparation and the large number of readily available chemistries make the monolithic separation media a vital alternative to capillary columns packed with particulate materials. This review summarizes the current state-of-the-art in this rapidly growing area of CEC with a focus on monolithic capillary columns prepared from synthetic polymers. Recent achievements in column technologies for both high-performance liquid chromatography and capillary electrophoresis are used as the starting point to highlight the influence of these well established analytical methods on the development of monolithic capillary columns for CEC. The effects of individual variables on the separation properties of monolithic capillaries are discussed in detail. The analytical potential of these columns is demonstrated with separations involving various families of compounds in different chromatographic modes.


Assuntos
Eletroforese Capilar/métodos , Polímeros/química , Géis/química , Porosidade , Solventes/química
9.
J Chromatogr A ; 852(1): 297-304, 1999 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-10480254

RESUMO

Porous monolithic columns have been prepared by the direct free radical copolymerization of glycidyl methacrylate and ethylene dimethacrylate within the confines of a 50x8 mm I.D. chromatographic column in the presence of porogens. The epoxide groups of these monoliths were modified to different extents by reaction with diethylamine to afford 1-N,N-diethylamino-2-hydroxypropyl functionalities useful for ion-exchange chromatography. Following characterization of the monoliths, the columns were tested in the chromatographic separation of a homologous series of oligodeoxyadenylic [pd(A)(12-18)] and oligothymidylic acids [d(pT)(12-24)] at different flow-rates. Very good separations of the oligonucleotides were achieved even at the high flow-rate of 4 ml/min.


Assuntos
Cromatografia Líquida de Alta Pressão/instrumentação , Cromatografia por Troca Iônica/instrumentação , Oligonucleotídeos/isolamento & purificação , Espectrofotometria Ultravioleta
10.
Chemosphere ; 33(12): 2411-21, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8976055

RESUMO

Behaviour of PCB added in the form of a technical mixture (Delor 106) and [14C]PCB 77 into different aqueous model cultivation media in long-term experiments was studied. The work was focused on monitoring PCB recovery from liquid media in the absence of micro-organisms. GC-ECD and radioanalysis were utilised for determination of PCB in the examined systems. Strong relations between duration of experiments, composition of media, degree of chlorination of biphenyls, and recovery of PCB were found. The lowest yields of PCB were observed for the extracts from model solutions based on N-limited cultivation media without veratryl alcohol and Tween 80. The addition of these components, mainly of Tween 80, caused a significant increase of PCB recoveries.


Assuntos
Biodegradação Ambiental , Mutagênicos/metabolismo , Bifenilos Policlorados/metabolismo , Álcoois Benzílicos/química , Radioisótopos de Carbono , Cromatografia Gasosa , Meios de Cultura , Marcação por Isótopo , Polissorbatos/química , Relação Estrutura-Atividade
11.
New York; U.S. National Center for Earthquake Engineering Research; Aug. 1993. (148) p. ilus, Tab.(Technical Report NCEER, 93-0016).
Monografia em En | Desastres | ID: des-6556

RESUMO

On October 12, 1992, a moderate earthquake occurred near Dahshur, Egypt, located about 20 km south of Cairo. The intensity of ground shaking at historic districts of Cairo was VI to VII using the Modified Mercalli scale and 212 of 560 monuments in Cairo were reportedly gamaged although none destroyed. nineteen days aftyer the earthquake, a reconnaissance team began making observations at 29 select Coptic and Islamic monuments, 24 of which had incurred some of the most significant damage. The team consisted of five professionals in the fields of architecture, architectural engineering, mathematical modeling, structural engineering, and geotechnical engineering from the United Stetes, Italy, and Turkey, who also provided expertise in the areas of earthquake engineering and the preservation of historic monuments. Damage to historic monuments can be generally described as having resulted from the continuous degradation of foundation and structural masonry from environmental effects, especially groundwater, inadequate lateral structural resistance, and the subsequent imposition of light to moderate earthquake forces. Other large earthquakes have affected old monuments in Cairo, but the recent earthquake may have caused a disproportionate amount of damage because of wide-spread poor structural conditional. This study has provided specific examples of how monuments ranging from 80 to about 1500 years in age, in various conditions, respond to near-field motions from a moderate-magnitude earthquake and helps to define problems that research studies can solve. It also provides strong evidence that a preservation strategy be adopted for historic monuments in Cairo that embraces scientific and engineering knowledge to understand these monuments and propose the least invasive repair and retrofit procedures.(AU)


Assuntos
Terremotos , Avaliação de Danos , Egito , Arquitetura
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