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1.
Healthcare (Basel) ; 12(13)2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38998865

RESUMO

This study examines the association between nurses' perception of caring and attitudes toward caring for dying patients in end-of-life care units. We used a descriptive cross-sectional design with convenience sampling. Data were collected from May to June 2021 through self-reported questionnaires from 303 Spanish nurses (mean age = 48 years, 78.9% female). Participants completed the Caring Dimension Inventory (CDI-25) and the Frommelt Attitudes Toward Care of the Dying scale. Demographic and training information were collected. Data were analyzed using Stata 16.0. Attitudes toward Care of the Dying Patient were significantly higher in nurses with palliative care training (ß = 2.829, p = 0.018) and those who scored higher on the psychosocial (ß = 0.789, p = 0.0001) and technical dimensions (ß = 0.487, p = 0.011) of the CDI-25. Multivariate analysis identified the psychosocial dimension of the CDI-25 scale (ß = 0.783, p = 0.0001) and palliative care training (ß = 2.686, p = 0.017) as the only significant variables associated with Attitudes toward Care of the Dying Patient. Overall, nurses exhibited a positive attitude toward caring for dying patients. Our results could potentially help nursing directors identify those with the necessary qualities and training for optimal end-of-life care and to further plan training courses to provide optimal care in end-of-life situations.

2.
Environ Res ; 252(Pt 2): 118918, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38614198

RESUMO

In this study, the removal of two emerging pollutants (EPs), antipyrine and acetanilide, through adsorption on activated carbons (ACs) prepared by chemical activation of Organosolv lignin with H3PO4 were evaluated. ACs with different pore size distribution were obtained at different impregnation ratios (H3PO4/lignin, 0.5-3.0 w/w) and activating temperatures (500-900 °C). The porosity and surface chemistry of the ACs were determined, and a bimodal size distribution of micropores and narrow mesopores was observed for the different ACs. These ACs were tested for antipyrine and acetanilide adsorption in aqueous solutions in a batch system at 20 °C and low concentration levels (0.5-10 ppm). In general, the ACs exhibited higher adsorption affinity to acetanilide than to antipyrine due to its smaller molecular size. Langmuir adsorption isotherm was able to describe the adsorption equilibrium data. A new Linear Driving Force (2-LDF) kinetic model, based on the bimodal size distribution of micropores and narrow mesopores observed for the ACs has been developed. The new model provided a more accurate description of the batch adsorption rates than that obtained from conventional kinetic models, and also enabled to relate the pore size distribution of the adsorbent with the adsorption kinetics. The validity of this model was checked in small-scale column fixed bed adsorption for the AC showing the highest affinity for both EP. The kinetic model and equilibrium adsorption isotherm obtained from the batch experiments were successfully used to provide an accurate description of the bed service time and the full breakthrough profile of acetanilide and antipyrine.


Assuntos
Acetanilidas , Antipirina , Lignina , Adsorção , Lignina/química , Antipirina/química , Acetanilidas/química , Carvão Vegetal/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/análise
3.
Appl Biochem Biotechnol ; 193(3): 777-790, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33188508

RESUMO

This research study evaluates various pre-treatments to improve sewage sludge solubilization prior to treatment by mesophilic anaerobic digestion. Microwave, thermal, and sonication pre-treatments were compared as these pre-treatments are the most commonly used for this purpose. The solubilization of sewage sludge was evaluated through the variation in soluble total organic carbon (sTOC, mg/L) and soluble total nitrogen (sTN, mg/L). Thermal and microwave pre-treatments increased sTOC/VS by 19.2% and 83.4% (VS, total volatile solids), respectively, after applying lower specific energy through (20 kJ/g TS, approximately) (TS, total solids) unlike the sonication pre-treatment, which required 136 kJ/g TS. Although sTN content did not increase significantly with the pre-treatments with respect to sTOC, both showed proportional trends. Sonication pre-treatments allowed the highest increase in volatile fatty acids (VFA) with respect to the raw sewage sludge (15% ∆VFA/sTOC). Methane production with and without pre-treatment was also evaluated. Methane production increased by 95% after applying sonication pre-treatment compared to the methane production of raw sewage sludge. Thermal and microwave pre-treatments entailed lower improvements (29% and 20%, respectively). Economically, thermal pre-treatments were the most viable alternative at real scale. Graphical abstract.


Assuntos
Reatores Biológicos , Metano/metabolismo , Micro-Ondas , Esgotos/microbiologia , Sonicação , Eliminação de Resíduos Líquidos , Anaerobiose
4.
J Venom Anim Toxins Incl Trop Dis ; 26: e20190079, 2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-32536942

RESUMO

BACKGROUND: Scolopendra polymorpha (S. polymorpha) is a predatory centipede whose venom contains a multiplicity of biochemical effectors that can cause muscle damage and cumulative cell destruction in its prey. Despite previous investigations of S. polymorpha and other centipede venoms, there is a lack of information on the morphological and biochemical patterns elicited by their myotoxic effects. To elucidate these processes, this paper presents evidence of skeletal muscle damage, and alterations in key biochemical mediators that appear only after exposure to centipede venom. METHODS: Venom was collected and fractionated using RP-HPLC; mouse extensor digitorum longus (EDL) muscle was exposed to whole venom and venom fractions to evaluate myotoxicity by means of creatine kinase (CK) - a muscle damage marker - activity measurements and histochemical analysis. RESULTS: CK activity was higher in EDL muscle exposed to venom than in unexposed muscle. This increase was observed after 15 min of venom incubation, and remained stable up to 45 min. Venom-exposed EDL muscle showed signs of muscle damage including necrosis, loss of fascicular structure as well as mitochondrial accumulations and ragged red fibers (RRF), suggesting an impairment in the normal mitochondrial arrangement. Nicotinamide adenine dinucleotide (NADH) and cytochrome oxidase (COX) tests also indicate that respiratory complexes might be affected. CONCLUSION: Our results suggest a different biochemical composition of S. polymorpha venom, based on the different effects of four venom fractions on the cells tested, according to statistical evidence. Fractions F6 and F7 caused the most important alterations.

5.
J. venom. anim. toxins incl. trop. dis ; 26: e20190079, 2020. graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1135133

RESUMO

Scolopendra polymorpha (S. polymorpha) is a predatory centipede whose venom contains a multiplicity of biochemical effectors that can cause muscle damage and cumulative cell destruction in its prey. Despite previous investigations of S. polymorpha and other centipede venoms, there is a lack of information on the morphological and biochemical patterns elicited by their myotoxic effects. To elucidate these processes, this paper presents evidence of skeletal muscle damage, and alterations in key biochemical mediators that appear only after exposure to centipede venom. Methods: Venom was collected and fractionated using RP-HPLC; mouse extensor digitorum longus (EDL) muscle was exposed to whole venom and venom fractions to evaluate myotoxicity by means of creatine kinase (CK) - a muscle damage marker - activity measurements and histochemical analysis. Results: CK activity was higher in EDL muscle exposed to venom than in unexposed muscle. This increase was observed after 15 min of venom incubation, and remained stable up to 45 min. Venom-exposed EDL muscle showed signs of muscle damage including necrosis, loss of fascicular structure as well as mitochondrial accumulations and ragged red fibers (RRF), suggesting an impairment in the normal mitochondrial arrangement. Nicotinamide adenine dinucleotide (NADH) and cytochrome oxidase (COX) tests also indicate that respiratory complexes might be affected. Conclusion: Our results suggest a different biochemical composition of S. polymorpha venom, based on the different effects of four venom fractions on the cells tested, according to statistical evidence. Fractions F6 and F7 caused the most important alterations.(AU)


Assuntos
Animais , Camundongos , Creatina Quinase , Miotoxicidade , Quilópodes , Bioquímica , Cromatografia Líquida de Alta Pressão
6.
Biomed Pharmacother ; 97: 496-502, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29091900

RESUMO

Ipomoea tyrianthina Lindley (syn. I. orizabensis Pelletan, Lebed. ex Steud., Convolvulaceae) is known as a purgative, but it has been also used in Mexican traditional medicine in the treatment of seizures and pain for their anticonvulsive, hypnotic and sedative properties. Some glycolipids isolated from this plant have shown significant effects on Central Nervous System, modifying inhibitory or excitatory processes. The mechanism for such activity it is not clear; studies with these metabolites have suggested that a pore-forming mechanism is involved in their activity. Therefore, the present work explores a possible not pore-forming mechanism related to the effect of four resin glycosides, Scammonin 1 (S-1), tyrianthin C (T-C), tyrianthin A (T-A) and tyrianthinic acid VI (TA-VI), isolated from Ipomoea tyrianthina root on GABAergic transmission system in cerebral cortex slices of mouse brain in an in vitro model. The results obtained show that all glycolipids tested evoked endogenous GABA release and increased its concentration within the incubation medium compared with controls; T-C demonstrated a dose-dependent effect. Sodium absence and guvacine presence did not affect significantly the activity of S-1 and T-C in contrast to T-A and TA-VI. S-1 and T-C effects were calcium-dependent, where GABA concentrations were considerably reduced. These results suggest that the increase of endogenous γ-aminobutyric acid (GABA) released evoked by these glycolipids is possibly done through a Na+- and/or Ca2+-dependent mechanisms, discarding a pore-forming mechanism.


Assuntos
Cálcio/metabolismo , Glicosídeos/farmacologia , Ipomoea , Resinas Vegetais/farmacologia , Sódio/metabolismo , Ácido gama-Aminobutírico/metabolismo , Animais , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Relação Dose-Resposta a Droga , Camundongos , Técnicas de Cultura de Órgãos , Raízes de Plantas , Resinas Vegetais/isolamento & purificação
7.
Biomed Pharmacother ; 94: 129-139, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28759750

RESUMO

Waltheria americana is a plant used in Mexican traditional medicine to treat some nervous system disorders. The aims of the present study were to isolate and determine the neuropharmacological and neurprotective activities of metabolites produced by a cell suspension culture of Waltheria americana. Submerged cultivation of W. americana cells provided biomass. A methanol-soluble extract (WAsc) was obtained from biomass. WAsc was fractionated yielding the chromatographic fractions 4WAsc-H2O and WAsc-CH2Cl2. For the determination of anticonvulsant activity in vivo, seizures were induced in mice by pentylenetetrazol (PTZ). Neuropharmacological activities (release of gamma amino butyric acid (GABA) and neuroprotection) of chromatographic fractions were determined by in vitro histological analysis of brain sections of mice post mortem. Fraction 4WAsc-H2O (containing saccharides) did not produce neuronal damage, neurodegeneration, interstitial tissue edema, astrocytic activation, nor cell death. Pretreatment of animals with 4WAsc-H2O and WAsc-CH2Cl2 from W. americana cell suspensions induced an increase in: GABA release, seizure latency, survival time, neuroprotection, and a decrease in the degree of severity of tonic/tonic-clonic convulsions, preventing PTZ-induced death of up to 100% of animals of study. Bioactive compounds produced in suspension cell culture of W. americana produce neuroprotective and neuropharmacological activities associated with the GABAergic neurotransmission system.


Assuntos
Malvaceae/química , Metaboloma , Fármacos Neuroprotetores/farmacologia , Extratos Vegetais/farmacologia , Animais , Anticonvulsivantes/farmacologia , Anticonvulsivantes/uso terapêutico , Biomassa , Córtex Cerebral/patologia , Feminino , Proteína Glial Fibrilar Ácida/metabolismo , Camundongos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Fármacos Neuroprotetores/uso terapêutico , Pentilenotetrazol , Extratos Vegetais/uso terapêutico , Convulsões/induzido quimicamente , Convulsões/tratamento farmacológico , Convulsões/patologia , Solubilidade , Suspensões , Ácido gama-Aminobutírico/metabolismo
9.
Acta sci., Health sci ; 37(2): 181-188, jul.-dez. 2015. tab
Artigo em Inglês | LILACS | ID: biblio-832100

RESUMO

The main objective of this study was to validate and examine the psychometric parameters of Profil der Lebensqualität Chronischkranker (PLC) in climacteric women. We conducted an exploratory research in Health Care and Treatment enrollment 280 participants. The data collection instruments were the PLC and the SF- 36 (Medical Outcomes Study 36 - Item Short - Form Health Survey). The original German version of PLC consists of 40 items that explore the biological and psychosocial items of daily life. The questionnaire was submitted to translation into Portuguese of Brazil, back translation, review by experts and cultural adaptation. For the psychometric study, Cronbach's alpha, factor analysis and the Pearson correlation coefficient were used.In the internal consistency analysis, Cronbach's alpha coefficient ranged from 0.81 a 0.89 in all categories, indicating that the instrument has adequate internal consistency. We could verify the existence of five factors that together explained 55.85% of total variance. For criterion validity, Pearson's correlation was between 0.41 and 0.78. Therefore, the Brazilian version of the PLC is configured in valid, reliable and easy-to-use option for assessment of quality of life in climacteric women.


O objetivo deste estudo foi validar e verificar os parâmetros psicométricos da Escala Profil der Lebensqualität Chronischkranker (PLC) para uma amostra de 280 mulheres climatéricas. Realizou-se uma pesquisa exploratória, cujos instrumentos de coleta foram o PLC e o SF-36 (Medical Outcomes Study 36 - Item Short - Form Health Survey). A versão original em alemão do PLC compõe- se de 40 itens que exploram os itens biológicos e psicossociais da vida diária. Foi realizada a tradução para o português do Brasil, retrotradução, revisão por painel de especialistas e adaptação cultural. Para o estudo psicométrico foram utilizados alfa de Cronbach, análise fatorial e coeficiente de Pearson. O coeficiente alfa de Cronbach variou de 0,81 a 0,89 em todas as categorias, apontando que o instrumento apresenta adequada consistência interna. Quanto à validade de constructo, verificou- se a existência de cinco fatores (estado de ânimo negativo, capacidade física, função social, estado de ânimo positivo e bem- estar social) que juntos explicam 55,85 % da variância total. Para validade de critério, os valores da correlação de Pearson situaram -se entre 0,41 e 0,78. Sendo assim, a versão brasileira do PLC configura-se em opção válida, confiável e de fácil aplicação para avaliação da qualidade de vida em mulheres climatéricas.


Assuntos
Humanos , Feminino , Qualidade de Vida , Climatério , Estudos Transversais , Estudo de Validação
10.
J Proteomics ; 111: 224-37, 2014 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-24780725

RESUMO

This communication reports the results of proteomic, transcriptomic, biochemical and electrophysiological analysis of the soluble venom and venom glands of the Mexican centipede Scolopendra viridis Say (here thereafter abbreviated S. viridis). Separation of the soluble venom permitted to obtain 54 different fractions, from which a mass finger printing analysis permitted the identification of at least 86 components, where 70% of the molecules have low molecular masses. Two-dimensional electrophoretic separation of this venom revealed the presence of about forty proteins with molecular weights ranging from 17 to 58kDa. The novo sequencing of 149 peptides obtained by LC-MS/MS from the 2D-gels showed the presence of proteins with amino acid sequences similar to several enzymes and venom allergens type 3. Furthermore, a total of 180 sequences were obtained from a cDNA library prepared with two venomous glands. From this, 155 sequences correspond to complete genes containing more than 200 base pairs each. Comparative sequence analyses of these sequences indicated the presence of different types of enzymes and toxin-like genes. Two proteins with molecular weights around 37,000 and 42,000Da were shown to contain hyaluronidase activity. Electrophysiological assays performed with soluble venom show that it decreases mammalian sodium channel currents. BIOLOGICAL SIGNIFICANCE: Animal venoms of Scolopendra species have been scarcely studied, although they have been reported to contain several bioactive compounds, some of which with potential therapeutic interest. The Mexican centipede S. viridis contains a powerful venom, capable of inflicting immediate effects on their preys. This communication is focused on the identification and description of a proteomic and transcriptomic analysis of the protein components of this venom. Several amino acid sequences similar to reported enzymes are the principal components in the S. viridis venom, but also a low number of toxins were identified. This knowledge should contribute to the understanding of the pharmacological effects caused by bites of this centipede species.


Assuntos
Venenos de Artrópodes/química , Artrópodes/química , Proteômica , Transcriptoma , Alérgenos , Animais , Astacoidea , Células CHO , Cromatografia Líquida , Biologia Computacional , Cricetulus , DNA Complementar/metabolismo , Eletroforese em Gel Bidimensional , Etiquetas de Sequências Expressas , Biblioteca Gênica , Gryllidae , Células HEK293 , Humanos , Hialuronoglucosaminidase/metabolismo , Peso Molecular , Peptídeos/química , Venenos de Escorpião/química , Espectrometria de Massas em Tandem
11.
Aten Primaria ; 44(1): 30-5, 2012 Jan.
Artigo em Espanhol | MEDLINE | ID: mdl-21496968

RESUMO

OBJECTIVE: The aim of this study is to determine the levels of burnout among employees of health care workers in the Health Area of Ceuta (Spain). DESIGN: Prevalence study. SETTING: Ceuta Health Area (Primary and Specialty Care). PARTICIPANTS: A sample of 200 workers stratified by sex, job and workplace. MEASUREMENTS: The tool used was the MBI (Maslach Burnout Inventory). We also studied personal (age, sex, marital status) and work variables (centre, job, age) and blood parameters (C-reactive protein and others). RESULTS: The burnout syndrome was present in 17.2% of workers (95% CI: 10.4-26.0). There was a significant relationship with job, with differences in emotional exhaustion, depersonalisation, and professional achievement. C-reactive protein was significantly higher in workers with burnout. CONCLUSIONS: Burnout prevalence in the health care workers in our sample is similar to other studies. The differences between health and non-health workers could be due to greater motivation for professional achievement, but they scored higher in exhaustion and depersonalisation. The increase in C-reactive protein, a non-specific inflammation marker, seems to confirm the findings of other studies.


Assuntos
Esgotamento Profissional/epidemiologia , Pessoal de Saúde , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Prevalência , Espanha/epidemiologia
12.
J Ethnopharmacol ; 135(2): 434-9, 2011 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-21440616

RESUMO

AIM OF THE STUDY: Ipomoea tyrianthina has been used in Mexican traditional medicine as a mild purgative, for the treatment of nervous disorders, and against tumors. In this study, the effect of convolvulin (an ether-insoluble resin glycoside) from the root of Ipomoea tyrianthina on: Central Nervous System; as spasmolytic and vasodilator; cytotoxic against cancer cell lines is evaluated. MATERIALS AND METHODS: Convolvulin isolated from the root of Ipomoea tyrianthina (IT-EM) was tested on pentylentetrazole induced seizures, pentobarbital-induced hypnosis, release of GABA and glutamic acid, isolated rat aorta and ileum rings, and against Caco-2 and KB cell lines. RESULTS: IT-EM increased the hypnotic effect induced by pentobarbital and the release of GABA in brain cortex of mice, but did not protect mice against pentylenetetrazole-induced convulsions. IT-EM produced a significant vasodilator effect in concentration- and endothelium-dependent manners on isolated rat aorta, but did not inhibit significantly contractions on rat ileum, colon, and jejune rings. IT-EM showed cytotoxic activity against nasopharyngeal carcinoma KB cell line. CONCLUSIONS: Convolvulin (IT-EM) from Ipomoea tyrianthina has sedative effect, vasorelaxant effect in concentration- and endothelium-dependent manners, and cytotoxic activity against nasopharyngeal carcinoma KB cell line.


Assuntos
Antineoplásicos/farmacologia , Glicosídeos/farmacologia , Hipnóticos e Sedativos/farmacologia , Ipomoea/química , Extratos Vegetais/química , Resinas Vegetais/farmacologia , Vasodilatadores/farmacologia , Animais , Linhagem Celular Tumoral , Humanos , Camundongos
13.
Bioorg Med Chem Lett ; 21(10): 3168-71, 2011 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-21397502

RESUMO

We have synthesized two new benzologues of Nitazoxanide (NIT) and Tizoxanide (TIZ), using a short synthetic route. Both compounds were tested in vitro against six protozoa (Giardia intestinalis, Trichomonas vaginalis, Entamoeba histolytica, Plasmodium berghei, Leishmania mexicana and Trypanosoma cruzi). Compound 1 (benzologue of NIT) showed broad antiprotozoal effect against all parasites tested, showing IC(50)'s<5 µM. This compound was five-times more active than NIT, and 18-times more potent than metronidazole against G. intestinalis. It was 10-times more active than pentamidine against L. mexicana, and it was sevenfold more potent than benznidazole versus T. cruzi. This compound could be considered as a new broad spectrum antiprotozoal agent.


Assuntos
Antiprotozoários/síntese química , Antiprotozoários/farmacologia , Tiazóis , Giardia/efeitos dos fármacos , Estrutura Molecular , Nitrocompostos , Plasmodium/efeitos dos fármacos , Tiazóis/síntese química , Tiazóis/farmacologia , Trichomonas vaginalis/efeitos dos fármacos
14.
J Ethnopharmacol ; 127(2): 551-4, 2010 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-19951739

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Ternstroemia pringlei represents one of the most widely employed and commercially exploited medicinal plant in Mexico, used popularly as a tranquilizer and for the treatment of insomnia. AIM OF THE STUDY: To investigate the sedative constituents of the plant through a bio-guided fractionation of extracts derived from calyx and fruits. MATERIALS AND METHODS: Crude extracts with different polarities (CHCl(3), AcOEt, MeOH, aqueous) were prepared and subjected to chromatographic fractionation, leading to the isolation of the sedative compound (1) from the MeOH crude extract. The identity of 1 was unequivocally established by means of 1D and 2D NMR spectroscopic analysis. The sleeping time induced by sodium pentobarbital and the elevated plus-maze models were performed on mice to determine the sedative and anxiolytic activities, respectively. Bioactivity was also investigated though in vitro GABA release experiments using mice brain slices. RESULTS: The sedative compound was established as jacaranone (1), and its effect was clearly demonstrated through a dose-dependent response analysis (ED(50) = 25 mg/kg mouse weight). When tested in the elevated plus-maze model, none of the extracts from Ternstroemia pringlei displayed anxiolytic activity. GABA release experiments showed that the MeOH and aqueous crude extracts released this neurotransmitter at a ratio of 217 and 179 pmol/g protein, respectively, evidencing the presence of other bioactive constituents in the extracts apart of 1, whose activity was absent in this model. CONCLUSIONS: Although 1 has been isolated and identified in a number of plant species, this is the first time that its sedative effect has been demonstrated. No previous record exists of other sedative compounds having been isolated from Ternstroemia pringlei.


Assuntos
Benzoquinonas/isolamento & purificação , Benzoquinonas/uso terapêutico , Brassicaceae , Flores , Hipnóticos e Sedativos/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/uso terapêutico , Theaceae , Árvores , Animais , Ansiedade/tratamento farmacológico , Ansiedade/psicologia , Benzoquinonas/farmacologia , Relação Dose-Resposta a Droga , Hipnóticos e Sedativos/farmacologia , Hipnóticos e Sedativos/uso terapêutico , Masculino , México , Camundongos , Camundongos Endogâmicos ICR , Extratos Vegetais/farmacologia
15.
Bioorg Med Chem Lett ; 19(16): 4652-6, 2009 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-19596196

RESUMO

Tyrianthins A (1) and B (2), two new partially acylated glycolipid ester-type heterodimers were isolated from Ipomoea tyrianthina. Scammonic acid A was determined as the glycosidic acid in both monomeric units. Tyrianthin A (1) (IC(50) 0.24+/-0.09 microM and E(max) 81.80+/-0.98%), and tyrianthin B (2) (IC(50) 0.14+/-0.08 microM and E(max) 87.68+/-0.72%) showed significant in vitro relaxant effect on aortic rat rings, in endothelium- and concentration-dependent manners. Also, these compounds were able to increase the release of GABA and glutamic acid in brain cortex, and displayed weak antimycobacterial activity.


Assuntos
Glicolipídeos/química , Ipomoea/química , Vasodilatadores/química , Animais , Antituberculosos/química , Antituberculosos/isolamento & purificação , Antituberculosos/farmacologia , Dimerização , Ácido Glutâmico/metabolismo , Glicolipídeos/isolamento & purificação , Glicolipídeos/farmacologia , Camundongos , Raízes de Plantas/química , Ratos , Vasodilatadores/isolamento & purificação , Vasodilatadores/farmacologia , Ácido gama-Aminobutírico/metabolismo
16.
Toxicon ; 54(1): 8-15, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19285520

RESUMO

Venom components from the centipede Scolopendra viridis Say were studied, using both the soluble venom and a cDNA library prepared from mRNA of the venomous glands. Separation of the soluble venom by high performance liquid chromatography (HPLC) permitted to obtain at least 54 different fractions. The fraction eluting at 46.24 min showed phospholipase activity. The enzyme was purified to homogeneity and the first 25 amino acid residues were identified by Edman degradation. From the cDNA library several genes were cloned, one of which codes for a protein with identical amino acid sequence as the one experimentally determined. The cloned gene codes for a signal peptide of 28 amino acids and a mature peptide of 119 residues. The molecular weight of the enzyme was estimated by mass spectrometry and shown to be 13,752 Da, which matches exactly with the molecular mass expected from the deduced amino acid sequence of the gene. Phylogenetic analysis of this sequence, in comparison with other known from venomous animals, showed that it is more similar to snake phospholipases than to insect or arachnid sequences, suggesting that it has been submitted to convergent evolution. To the best of our knowledge this is the first time that a phospholipase from this species of animal is fully characterized. We have named it Scol/Pla.


Assuntos
Venenos de Artrópodes/genética , Venenos de Artrópodes/toxicidade , Artrópodes/fisiologia , Fosfolipases A2/genética , Fosfolipases A2/toxicidade , Sequência de Aminoácidos , Animais , Venenos de Artrópodes/enzimologia , Artrópodes/classificação , Artrópodes/genética , Sequência de Bases , Clonagem Molecular , DNA Complementar/biossíntese , DNA Complementar/química , DNA Complementar/genética , Biblioteca Gênica , Dados de Sequência Molecular , Filogenia
17.
J Pineal Res ; 46(1): 29-35, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18513209

RESUMO

Aging is a complex process associated with a diminished ability to respond to stress, a progressive increase in free radical generation and a decline in immune function. Melatonin, a molecule with a great functional versatility exerts anti-oxidant, oncostatic, immunomodulatory, and anti-aging properties. Melatonin levels drop during aging and it has been speculated that the loss of melatonin may accelerate aging. This study was designed to elucidate whether aging involves responsiveness to reduced melatonin. Melatonin membrane receptor (MT1 and MT2) expression and MT1 protein expression were analyzed in extrapineal tissues (thymus, spleen, liver, kidney, and heart) of 3- and 12-month-old rats using real time polymerase chain reaction and western blotting analysis. Moreover, melatonin in tissues was measured by high performance liquid chromatography. We report for the first time, an age-related reduction in mRNA MT1 and MT2 expression levels as well as MT1 protein expression in all tissues tested except the thymus, where surprisingly, both melatonin receptor levels were significantly higher in 12-month-old rats and MT1 protein expression maintained unchanged with age. Diminished melatonin concentrations were measured in spleen, liver, and heart during aging. As a conclusion, physiological aging seems to exert responsiveness to melatonin and consequently, the loss of this potent anti-oxidant may contribute to onset of aging.


Assuntos
Envelhecimento/metabolismo , Receptor MT1 de Melatonina/biossíntese , Receptor MT2 de Melatonina/biossíntese , Envelhecimento/genética , Animais , Western Blotting , Cromatografia Líquida de Alta Pressão , Expressão Gênica , Fígado/metabolismo , Masculino , Melatonina/metabolismo , Miocárdio/metabolismo , Glândula Pineal/metabolismo , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Ratos , Ratos Wistar , Receptor MT1 de Melatonina/genética , Receptor MT2 de Melatonina/genética , Baço/metabolismo , Estatísticas não Paramétricas , Timo/metabolismo
18.
Bioorg Med Chem Lett ; 18(11): 3147-51, 2008 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-18486471

RESUMO

A series of ten novel hybrids from benzimidazole and pentamidine were prepared using a short synthetic route. Each compound was tested in vitro against the protozoa Trichomonas vaginalis, Giardia lamblia, Entamoeba histolytica, Leishmania mexicana, and Plasmodium berghei, in comparison with pentamidine and metronidazole. Some analogues showed high bioactivity in the low micromolar range (IC(50)<1 microM) against the first four protozoa, which make them significantly more potent than either standard. 1,5-bis[4-(5-methoxy-1H-benzimidazole-2-yl)phenoxy]pentane (2) was 3- and 9-fold more potent againstG. lamblia than metronidazole and pentamidine, respectively. This compound was 23-, 108-, and 13-fold more active than pentamidine against T. vaginalis, E. histolytica and L. mexicana, respectively. Studying further structure-activity relationships through the use of bioisosteric substitution in these hybrids should provide new leads against protozoal diseases.


Assuntos
Antiprotozoários/síntese química , Antiprotozoários/farmacologia , Benzimidazóis/síntese química , Benzimidazóis/farmacologia , Desenho de Fármacos , Pentamidina/síntese química , Pentamidina/farmacologia , Animais , Antiprotozoários/química , Benzimidazóis/química , Entamoeba histolytica/efeitos dos fármacos , Giardia lamblia/efeitos dos fármacos , Concentração Inibidora 50 , Leishmania mexicana/efeitos dos fármacos , Metronidazol/farmacologia , Estrutura Molecular , Testes de Sensibilidade Parasitária , Pentamidina/química , Plasmodium berghei/efeitos dos fármacos , Relação Estrutura-Atividade , Trichomonas vaginalis/efeitos dos fármacos
19.
Virology ; 368(1): 41-9, 2007 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-17643462

RESUMO

T cell response against HBV is vigorous in patients with acute hepatitis who clear the virus, whereas it is weak and narrowly focused in patients with chronic disease. We report that following incubation with HBcAg, a population of CD4+FoxP3+ cells expressing phenotypic markers of both natural and induced Tregs, can be antigen-induced from peripheral mononuclear cells. Conversely, naive and naturally immune subjects did not increase CD4+FoxP3+ Tregs following stimulation with HBcAg, supporting the idea that natural Tregs are able to respond specifically to HBV antigen. Furthermore, increased frequencies of antigen-induced CD4+FoxP3+IL-10+ Tregs correlated with viral load, suggesting that antigen-induced Tregs could contribute to an inadequate response against the virus, leading to chronic infection and support the view that specific natural Tregs may be implicated in host immune tolerance during HBV infection.


Assuntos
Antígenos do Núcleo do Vírus da Hepatite B/imunologia , Vírus da Hepatite B/imunologia , Hepatite B/imunologia , Linfócitos T Reguladores/imunologia , Adulto , Linfócitos T CD4-Positivos/química , Linfócitos T CD4-Positivos/imunologia , Doença Crônica , Fatores de Transcrição Forkhead/análise , Humanos , Interleucina-10/análise , Pessoa de Meia-Idade , Subpopulações de Linfócitos T/imunologia , Carga Viral
20.
J Ethnopharmacol ; 110(2): 364-7, 2007 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-17113736

RESUMO

Heliopsis longipes (Compositae) is a Mexican plant used as analgesic in pain toothache. A solution of 10mug/ml of dichloromethane extract from this plant showed analgesic activity determined by means of GABA release in mice brain slices. Through a bioassay-directed separation, fractions G-1, G-2, G-4 and G-6 at the same concentration were active. Affinin was the unique and common active compound, and evoke the GABA release 0.5min after administration at 1x10(-4)M concentration. Inactive compound were undeca-2E-en-8,10-dyinoic acid isobutylamide, hinokinin, 2'-hydroxyhinokinin, 3beta-sn-glyceroyl-(1''-palmitoxy)urs-12-ene, 13(18)-ursen-3beta-ol, 13(18)-ursen-3beta-acetate, beta-sitosterol and stigmasterol. The analgesic activity of Heliopsis longipes could be associated to affinin.


Assuntos
Alcenos/farmacologia , Amidas/farmacologia , Analgésicos/farmacologia , Asteraceae/química , Dor/tratamento farmacológico , Extratos Vegetais/farmacologia , Alcamidas Poli-Insaturadas/farmacologia , 4-Butirolactona/análogos & derivados , 4-Butirolactona/isolamento & purificação , Alcenos/isolamento & purificação , Amidas/isolamento & purificação , Analgésicos/isolamento & purificação , Animais , Benzodioxóis , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Dioxóis/isolamento & purificação , Feminino , Técnicas In Vitro , Lignanas/isolamento & purificação , Medicina Tradicional , Cloreto de Metileno , México , Camundongos , Plantas Medicinais , Alcamidas Poli-Insaturadas/isolamento & purificação , Ácido gama-Aminobutírico/efeitos dos fármacos , Ácido gama-Aminobutírico/metabolismo
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