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1.
Braz J Biol ; 83: e274806, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38126633

RESUMO

Chicken (Gallus gallus domesticus) is one of the primary sources of animal protein for the Brazilian population. Thus, the safety of this food is highly relevant. This study was based on the evidence of severe contamination of these animals by metals such as lead in Santo Amaro, Bahia. This exploratory study aimed to evaluate associations between lead levels in blood of chicken exposed to a contaminated area with the occurrence of chromosomal alterations, evidencing genotoxic effects. Serum lead analysis was performed by GF-AAS after dilution with a matrix modifier solution (Triton X-100 0.2% v/v and HNO3 0.1% v/v), while chromosomal damage was evaluated using the comet assay. The results showed genotoxic effects (positive comet assay) only for the specimen sample with higher serum lead concentrations (33.9 µg dL-1), suggesting the occurrence of toxic effects at this level of exposure. This work evaluated a relationship between the reduction of serum lead levels in chicken and increased distance from the primary polluting source - a lead processing plant (COBRAC). It also showed that lead is bioavailable in this territory, contaminating chicken and causing genotoxic effects in these animals, further expanding the concern with the local biota and the health of the residents of Santo Amaro.


Assuntos
Galinhas , Chumbo , Animais , Chumbo/toxicidade , Brasil , Ensaio Cometa , Cromossomos
2.
Lett Appl Microbiol ; 72(1): 41-52, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32910828

RESUMO

The use of rosemary essential oil (RO) and its combination with nisin (RO+N) in preventing the multiplication of Alicyclobacillus acidoterrestris in orange juice was evaluated. The minimum inhibitory and bactericidal concentrations (MIC and MBC) for RO were both 125 µg ml-1 while RO+N displayed a synergistic effect. The use of RO and RO+N at concentrations of 1, 4 and 8× MIC in orange juice for 96 h was evaluated in terms of their sporicidal effectiveness. With regard to the action against A. acidoterrestris spores, RO at 8× MIC was sporostatic, whereas RO+N at 1× MIC was sporicidal. Morphological changes in the structure of the micro-organism after treatment were also observed by microscopy. Furthermore, flow cytometric analysis showed that most cells were damaged or killed after treatment. In general, the antioxidant activity after addition of RO+N decreased with time. The results demonstrate that using the combination of RO and nisin can prevent the A. acidoterrestris growth in orange juice.


Assuntos
Alicyclobacillus/crescimento & desenvolvimento , Antibacterianos/farmacologia , Sucos de Frutas e Vegetais/microbiologia , Nisina/farmacologia , Óleos Voláteis/farmacologia , Rosmarinus/química , Alicyclobacillus/efeitos dos fármacos , Citrus sinensis
3.
Zygote ; 25(2): 111-119, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28264730

RESUMO

Previous investigations suggested that elevated cell-free DNA (cfDNA) can indicate non-healthy states. However, the potential association between cfDNA seminal plasma levels and fertility sperm parameters has not yet been determined. Therefore, the present study evaluated the association between seminal cfDNA levels and sperm fertility criteria to determine the use of seminal cfDNA quantification. An in vivo protocol quantified cfDNA levels of semen samples obtained from 163 male patients using fluorescent PicoGreen dye staining. To confirm if semen cfDNA quantification is realistic, an in vitro complementary test was performed using three or four semen samples. The fresh sperm samples were exposed to paraquat that generates high levels of superoxide anion causing oxidative stress and cell mortality. The results showed significant association between dsDNA levels and several sperm fertility parameters, such as low viability and alterations of motility and morphology. The in vitro analysis confirmed the association between dsDNA levels and sperm viability. Together, these results suggest that dsDNA levels could be an important biomarker to test sperm fertility.


Assuntos
DNA/análise , Corantes Fluorescentes/química , Infertilidade Masculina/fisiopatologia , Análise do Sêmen/métodos , Sêmen/química , Motilidade dos Espermatozoides , Adulto , Sistema Livre de Células , Humanos , Masculino , Compostos Orgânicos/química , Estresse Oxidativo
4.
Lupus ; 24(14): 1562-6, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26251401

RESUMO

We report a case of a patient with localized discoid lupus erythematosus (DLE) who was found to have high-grade squamous dysplasia (carcinoma in situ) over the upper lip. This report also consists of a brief review of 16 other cases of DLE with squamous cell carcinoma (SCC) we came across while going through the literature in an Indian scenario.Incidence of SCC over DLE in the Indian population is found to be 0.98% to 3.4% with a male-to-female ratio of 1.6:1. The latent period between onset of DLE and development of SCC was 9.59 ± 5.6 years.There was history of chronic sun exposure in 81.8% of patients, which indicates a possible role of prolonged ultraviolet light exposure in malignant transformation. The lips were the most commonly affected area (28.57%), with the upper lip being more commonly involved than the lower lip. We also observed that the latent period (5 ± 2.7 years) in lip tumours was shorter than that in other sites (11.22 ± 6.78 years), indicating a more rapid transformation in lips (p value = 0.038). Well differentiated was the most common (46.2%) type of SCC noted. Lymph node involvement was found in three of 17 cases (25%) and one case (8.3%) had recurrence of lesions after excision.We conclude that in India though SCC is rare per se, its occurrence in the context of DLE is not uncommon and is aggressive in nature.


Assuntos
Carcinoma de Células Escamosas/complicações , Carcinoma de Células Escamosas/etiologia , Lúpus Eritematoso Discoide/complicações , Lúpus Eritematoso Discoide/patologia , Anticorpos Antinucleares/análise , Povo Asiático , Biópsia , Carcinoma in Situ/patologia , Feminino , Humanos , Índia , Neoplasias Labiais/patologia , Masculino , Pessoa de Meia-Idade
5.
J Dent Res ; 94(7): 990-7, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25861800

RESUMO

The effect of chronic fluoride (F) exposure from the drinking water on parameters related to glucose homeostasis was investigated. Wistar rats were randomly distributed into 2 groups (diabetic [D] and nondiabetic [ND]; n = 54 each). In D, diabetes was induced with streptozotocin. Each group was further divided into 3 subgroups (0, 10, or 50 mgF/L in drinking water). After 22 days of treatment, plasma and liver samples were collected. No alterations in glycemia, insulinemia, K(ITT), and HOMA2-IR (homeostasis model assessment 2 of insulin resistance) were seen for ND. F-exposure of D rats led to significantly lower insulinemia, without alterations in glycemia (increased %S). Proteomic analysis detected 19, 39, and 16 proteins differentially expressed for the comparisons D0 vs. D10, D0 vs. D50, and D10 vs. D50, respectively. Gene Ontology with the most significant terms in the comparisons D0 vs. D10, D0 vs. D50, and D50 vs. D10 were organic acid metabolic process and carboxylic acid metabolic process, organic acid metabolic process, and cellular ketone metabolic process. Analysis of subnetworks revealed that proteins with fold changes interacted with GLUT4 in comparison D0 vs. D10. Among these proteins, ERj3p was present in D10. Upregulation of this protein in the presence of F might help to explain the higher %S found in these animals. These data suggest that fluoride might enhance glucose homeostasis in diabetes and identify specific biological mechanisms that merit future studies.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Fluoretos/administração & dosagem , Glucose/metabolismo , Hipoglicemiantes/administração & dosagem , Resistência à Insulina , Animais , Glicemia/análise , Ácidos Carboxílicos/metabolismo , Relação Dose-Resposta a Droga , Fluoretos/análise , Ontologia Genética , Transportador de Glucose Tipo 4/metabolismo , Proteínas de Choque Térmico HSP40/metabolismo , Homeostase/fisiologia , Hipoglicemiantes/análise , Insulina/sangue , Cetonas/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Dobramento de Proteína , Proteoma/análise , Distribuição Aleatória , Ratos , Ratos Wistar , Estreptozocina , Abastecimento de Água
6.
Eur J Prosthodont Restor Dent ; 21(3): 127-34, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24261105

RESUMO

The aim of this study was to investigate the current guidelines used for the undergraduate course subject Removable Partial Denture in Portuguese Dental Schools following the Bologna Process. All Dental Schools were sent a questionnaire, divided into the following areas: (I) organization and syllabus; (II) teaching methods; (III) materials and techniques; Answers about organization and syllabus of course subjects showed the most variability; teaching methods were identical regarding principal textbook and live demonstrations of laboratory/clinical procedures; the same techniques and materials are used in all the schools' dental clinics. The majority of Dental Schools present similar guidelines for removable partial dentures.


Assuntos
Planejamento de Dentadura , Prótese Parcial Removível , Educação em Odontologia , Prostodontia/educação , Currículo , Educação em Odontologia/métodos , Humanos , Portugal , Faculdades de Odontologia , Inquéritos e Questionários
7.
Kathmandu Univ Med J (KUMJ) ; 11(41): 91-3, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23774424

RESUMO

Incontinentia pigmenti is an X- linked dominant condition characterized by cutaneous lesions associated with developmental defects of the eye, skeletal system and central nervous system. We report a case of incontinentia pigmenti in a 30 day old female infant who presented to us with skin eruptions over bilateral upper limbs, lower limbs and trunk since birth. She had linear verrucous plaques and vesicles distributed along the Blaschko's lines in addition to macular hyperpigmentation in a linear and whorled pattern involving the concerned areas. On ophthalmological examination, proliferative retinopathy in the right eye was noted.


Assuntos
Incontinência Pigmentar/diagnóstico , Pele/patologia , Vitreorretinopatia Proliferativa/complicações , Biópsia , Diagnóstico Diferencial , Feminino , Angiofluoresceinografia , Fundo de Olho , Humanos , Incontinência Pigmentar/complicações , Recém-Nascido , Vitreorretinopatia Proliferativa/diagnóstico
8.
Leukemia ; 26(3): 481-9, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21860432

RESUMO

Myeloproliferative neoplasms are characterized by overproduction of myeloid lineage cells with frequent acquisition of oncogenic JAK2V617F kinase mutations. The molecular mechanisms that regulate energy requirements in these diseases are poorly understood. Transformed cells tend to rely on fermentation instead of more efficient oxidative phosphorylation for energy production. Our data in JAK2V617F-transformed cells show that growth and metabolic activity were strictly dependent on the presence of glucose. Uptake of glucose and cell surface expression of the glucose transporter Glut1 required the oncogenic tyrosine kinase. Importantly, JAK2V617F as well as active STAT5 increased the expression of the inducible rate-limiting enzyme 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3 (PFKFB3), which controls glycolytic flux through 6-phosphofructo-1-kinase. PFKFB3 was required for JAK2V617F-dependent lactate production, oxidative metabolic activity and glucose uptake. Targeted knockdown of PFKFB3 also limited cell growth under normoxic and hypoxic conditions and blocked in vivo tumor formation in mice. Overall, these data suggest that inducible PFKFB3 is required for increased growth, metabolic activity and is regulated through active JAK2 and STAT5. Novel therapies that specifically block PFKFB3 activity or expression would, therefore, be expected to inhibit JAK2/STAT5-dependent malignancies and related cancers.


Assuntos
Frutose-Bifosfatase/genética , Frutose-Bifosfatase/metabolismo , Janus Quinase 2/genética , Janus Quinase 2/metabolismo , Fosfofrutoquinase-2/genética , Animais , Linhagem Celular Tumoral , Proliferação de Células , Transformação Celular Neoplásica/genética , Feminino , Glucose/metabolismo , Transportador de Glucose Tipo 1/genética , Transportador de Glucose Tipo 1/metabolismo , Humanos , Camundongos , Camundongos SCID , Fosfofrutoquinase-2/metabolismo , Fator de Transcrição STAT5/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Leukemia ; 25(2): 281-9, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21072051

RESUMO

Transformation by tyrosine kinase oncogenes (TKOs) in myeloid malignancies, including BCR-ABL in chronic myeloid leukemia, FLT3ITD in acute myeloid leukemia or JAK2V617F in myeloproliferative neoplasms, is associated with increased growth and cytoskeletal abnormalities. Using targeted approaches against components of the superoxide-producing NADPH-oxidases, including NADPH oxidase 2 (NOX2), NOX4 and the common p22(phox) subunit of NOX1-4, myeloid cells were found to display reduced cell growth and spontaneous migration. Consistent with a role of NOXs as regulators of membrane proximal signaling events in nonphagocytic cells, NOX2 and NOX4 were not involved in the excess production of intracellular reactive oxygen species and did not significantly increase oxygen consumption. All NOX family members are controlled in part through levels of the rate-limiting substrate NADPH, which was found to be significantly elevated in TKO-transformed cells. Also, reduced phosphorylation of the actin filament crosslinking protein myristoylated alanine-rich C-kinase substrate (MARCKS) in response to suppression of p22(phox) hints at a novel effector of NOX signaling. MARCKS was also found to be required for increased migration. Overall, these data suggest a model whereby NOX links metabolic NADPH production to cellular events that directly contribute to transformation.


Assuntos
Movimento Celular , Proliferação de Células , Transformação Celular Neoplásica , Células Mieloides/patologia , NADPH Oxidases/fisiologia , Proteínas Tirosina Quinases/genética , Animais , Linhagem Celular , Humanos , Leucemia Mieloide/etiologia , Leucemia Mieloide/patologia , Camundongos , NADP/biossíntese , Oncogenes
10.
Artigo em Inglês | MEDLINE | ID: mdl-21097031

RESUMO

We present a new type of flexible dry copper electrodes based on Polydimethylsiloxane (PDMS) coatings, requiring no electrical contact with the body. Tests were performed in order to evaluate the performance of these types of electrodes using electro-optic techniques, suitable for wearable devices. Conductive and insulated PDMS layers were fabricated through a spin coating process, reaching a thickness of 100µ. These layers were then deposited on top of a flexible copper sheet. In a first set of experiments PDMS-based electrodes were compared with Ag/AgCl pre-gelled electrodes, showing comparable performances and lower noise signals. In order to test the influence of electrode area into signal strength, different sizes were chosen: 10.14 cm(2), 17.55 cm(2), 25.3 cm(2) and 39 cm(2). The results have shown that the signal strength increases with electrode area. We have also tested the influence of PDMS conductivity in signal strength, by adding two types of nickel to the pre-polymer solution. PDMS conductive electrodes have shown slightly better performances, with amplitudes higher than 200mV, which is the maximum value recorded with PDMS insulated electrodes.


Assuntos
Dimetilpolisiloxanos/química , Eletrodos , Eletroencefalografia/instrumentação , Monitorização Ambulatorial/instrumentação , Nylons/química , Imagens com Corantes Sensíveis à Voltagem/instrumentação , Materiais Biocompatíveis/química , Módulo de Elasticidade , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos
11.
Hum Reprod Update ; 15(1): 119-38, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-18936037

RESUMO

BACKGROUND: The steroid hormone progesterone is indispensable for mammalian procreation by controlling key female reproductive events that range from ovulation to implantation, maintenance of pregnancy and breast development. In addition to activating the progesterone receptors (PRs)-B and -A, members of the superfamily of ligand-dependent transcription factors, progesterone also elicits a variety of rapid signalling events independently of transcriptional or genomic regulation. This review covers our current knowledge on the mechanisms and relevance of non-genomic progesterone signalling in female reproduction. METHODS: PubMed was searched up to August 2008 for papers on progesterone actions in ovary/breast/endometrium/myometrium/brain, focusing primarily on non-genomic signalling mechanisms. RESULTS: Convergence and intertwining of rapid non-genomic events and the slower transcriptional actions critically determine the functional response to progesterone in the female reproductive system in a cell-type- and environment-specific manner. Several putative progesterone-binding moieties have been implicated in rapid signalling events, including the 'classical' PR and its variants, progesterone receptor membrane component 1, and the novel family of membrane progestin receptors. Progesterone and its metabolites have also been implicated in the allosteric regulation of several unrelated receptors, such as gamma-aminobutyric acid type A, oxytocin and sigma(1) receptors. CONCLUSIONS: Identification of the mechanisms and receptors that relay rapid progesterone signalling is an area of research fraught with difficulties and controversy. More in-depth characterization of the putative receptors is required before the non-genomic progesterone pathway in normal and pathological reproductive function can be targeted for pharmacological intervention.


Assuntos
Progesterona/fisiologia , Reprodução/fisiologia , Encéfalo/metabolismo , Mama/metabolismo , Endométrio/metabolismo , Feminino , Genoma Humano , Humanos , Miométrio/metabolismo , Ovário/metabolismo , Progesterona/metabolismo , Receptores de Progesterona/fisiologia , Transdução de Sinais
12.
Methods Find Exp Clin Pharmacol ; 30(3): 209-14, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18597005

RESUMO

This study evaluated the kinetics of fluoride in plasma, femur surface and the whole femur of rats, after chronic exposure to different water fluoride levels was interrupted. Four groups of Wistar rats received drinking water containing 0, 5, 15 or 50 microg F/ml for 60 days (n = 50/group). The animals were euthanized immediately after exposure to fluoride or after 7, 30, 90 or 180 days (n = 10/subgroup). Plasma and femurs were collected. Fluoride on the femur surface, whole femur and plasma was analyzed with an electrode. Data were analyzed using ANOVA and Tukey's test (p< 0.05). The increase in plasma fluoride levels was significant only for the 50 microg F/ml group at 0 and 7 days. Regarding bone surface and whole bone, for most groups, significant increases in fluoride concentrations were observed with the increase in water fluoride concentrations at each time of euthanasia. For fluoride doses up to 15 microg F/ml, femur surface fluoride levels were reestablished 180 days after the exposure was discontinued, which was not valid for whole femur or for higher fluoride doses. We found a different kinetics of fluoride in plasma, femur surface and the whole femur of rats after chronic exposure to fluoride is interrupted.


Assuntos
Osso e Ossos/química , Cariostáticos/análise , Cariostáticos/farmacocinética , Fluoretos/análise , Fluoretos/farmacocinética , Animais , Cariostáticos/administração & dosagem , Relação Dose-Resposta a Droga , Feminino , Fêmur/química , Fluoretos/administração & dosagem , Minerais/química , Ratos , Ratos Wistar , Fatores de Tempo , Distribuição Tecidual
13.
Phytother Res ; 21(8): 771-6, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17486685

RESUMO

Ilex paraguariensis St Hilaire (Aquifoliaceae) is a plant widely cultivated in South America and with various reputed medicinal properties that can be attributed to phenolic constituents of the leaves: caffeine, theophylline and theobromine, besides the flavonoids, quercetin and rutin. This study examined the antiparkinsonian activity of the hydroalcohol extract of Ilex paraguariensis in models of protection against cerebral injury induced by MPTP and reversal of the catatonia induced by reserpine in mice. The hydroalcohol extract prevented MPTP-induced hypolocomotion at doses of 250 and 500 mg/kg at the all time points observed and also prevented the reserpine-induced catalepsy at the same doses. The extract potentiated the effect of apomorphine in preventing catatonia, suggesting a non-dopaminergic activity, probably through antagonism of adenosine. In biochemical studies the hydroalcohol extract caused a significant decrease in the NO levels, exhibited a DPPH-scavenging ability and was effective in preventing the oxidation of deoxyribose. The results obtained suggest that the hydroalcohol extract of Ilex paraguariensis may have an antiparkinsonian profile in animal models, probably through its antioxidant activity and antagonist action on adenosine A(2A) receptors.


Assuntos
Ilex paraguariensis/química , Transtornos Parkinsonianos/tratamento farmacológico , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/farmacologia , Animais , Modelos Animais de Doenças , Radical Hidroxila , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Reserpina/toxicidade
14.
Artigo em Inglês | MEDLINE | ID: mdl-16257551

RESUMO

The respiratory cycles of Rana and Bufo has been disputed in relation to flow patterns and to the respiratory dead-space of the buccal volume. A small tidal volume combined with a much larger buccal space motivated the "jet steam" model that predicts a coherent expired flow within the dorsal part of the buccal space. Some other studies indicate an extensive mixing of lung gas within the buccal volume. In Bufo schneideri, we measured arterial, end-tidal and intrapulmonary PCO(2) to evaluate dead-space by the Bohr equation. Dead-space was also estimated as: V(D)=(total ventilation-effective ventilation)/f(R), where total ventilation and f(R) were measured by pneumotachography, while effective ventilation was derived from the alveolar ventilation equation. These approaches were consistent with a dead space of 30-40% of tidal volume, which indicates a specific pathway for the expired lung gas.


Assuntos
Bufonidae/fisiologia , Ventilação Pulmonar/fisiologia , Espaço Morto Respiratório/fisiologia , Animais , Dióxido de Carbono/sangue , Volume de Ventilação Pulmonar/fisiologia
15.
J Endocrinol ; 187(1): 89-101, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16214944

RESUMO

Rapid non-genomic actions of progesterone are implicated in many aspects of female reproduction. Recently, three human homologues of the fish membrane progestin receptor (mPR) have been identified. We combined bioinformatic analysis with expression profiling to define further the role of these mPRs in human reproductive tissues. Sequence analysis confirmed that the mPRs belong to a larger, highly conserved family of proteins, termed 'progestin and adiponectin receptors' (PAQRs). A comparison of the expression of mPR transcripts with that of two related PAQR family members, PAQRIII and PAQRIX, in cycling endometrium and pregnancy tissues revealed markedly divergent expression levels and profiles. For instance, endometrial expression of mPRalpha and gamma and PAQRIX was cycle-dependent whereas the onset of parturition was associated with a marked reduction in myometrial mPRalpha and beta transcripts. Interestingly, mPRalpha and PAQRIX were most highly expressed in the placenta, and the tissue expression levels of both genes correlated inversely with that of the nuclear PR. Phylogenetic analysis demonstrated that PAQRIX belongs to the mPR subgroup of proteins. We also validated a polyclonal antibody raised against the carboxy-terminus of human mPRalpha. Immunohistochemical analysis demonstrated more intense immunoreactivity in placental syncytiotrophoblasts than in endometrial glands or stroma. The data suggest important functional roles for mPRalpha, and possibly PAQRIX, in specific reproductive tissues, particularly those that express low levels of nuclear PR.


Assuntos
Membrana Celular/metabolismo , Endométrio/metabolismo , Trabalho de Parto/metabolismo , Miométrio/metabolismo , Placenta/metabolismo , Receptores de Progesterona/genética , Adulto , Análise de Variância , Anticorpos Monoclonais/isolamento & purificação , Sequência de Bases , Clonagem Molecular , Biologia Computacional , Primers do DNA , Membranas Extraembrionárias/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Ciclo Menstrual/metabolismo , Microscopia Confocal , Dados de Sequência Molecular , Gravidez , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Receptores de Progesterona/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Alinhamento de Sequência , Estatísticas não Paramétricas
16.
Regul Pept ; 120(1-3): 167-75, 2004 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-15177935

RESUMO

In the present paper, the modulation of the basolateral membrane (BLM) Na+ -ATPase activity of inner cortex from pig kidney by angiotensin II (Ang II) and angiotensin-(1-7) (Ang-(1-7)) was evaluated. Ang II and Ang-(1-7) inhibit the Na+ -ATPase activity in a dose-dependent manner (from 10(-11) to 10(-5) M), with maximal effect obtained at 10(-7) M for both peptides. Pharmacological evidences demonstrate that the inhibitory effects of Ang II and Ang-(1-7) are mediated by AT2 receptor: The effect of both polypeptides is completely reversed by 10(-8) M PD 123319, a selective AT2 receptor antagonist, but is not affected by either (10(-12) - 10(-5) M) losartan or (10(-10)-10(-7) M) A779, selective antagonists for AT1 and AT(1-7) receptors, respectively. The following results suggest that a PTX-insensitive, cholera toxin (CTX)-sensitive G protein/adenosine 3',5'-cyclic monophosphate (cAMP)/PKA pathway is involved in this process: (1) the inhibitory effect of both peptides is completely reversed by 10(-9) M guanosine 5'-O-(2-thiodiphosphate) (GDPbetaS; an inhibitor of the G protein activity), and mimicked by 10(-10) M guanosine 5'-O-(3-thiotriphosphate) (GTPgammaS; an activator of the G protein activity); (2) the effects of both peptides are mimicked by CTX but are not affected by PTX; (3) Western blot analysis reveals the presence of the Gs protein in the isolated basolateral membrane fraction; (4) (10(-10)-10(-6) M) cAMP has a similar and non-additive effect to Ang II and Ang-(1-7); (5) PKA inhibitory peptide abolishes the effects of Ang II and Ang-(1-7); and (6) both angiotensins stimulate PKA activity.


Assuntos
Angiotensina II/análogos & derivados , Angiotensina II/farmacologia , Angiotensina I/farmacologia , Anti-Hipertensivos/farmacologia , Córtex Renal/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Receptor Tipo 2 de Angiotensina/metabolismo , ATPase Trocadora de Sódio-Potássio/metabolismo , Vasoconstritores/farmacologia , Adjuvantes Imunológicos/farmacologia , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Bloqueadores do Receptor Tipo 2 de Angiotensina II , Animais , Toxina da Cólera/farmacologia , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Guanosina Difosfato/metabolismo , Guanosina Trifosfato/metabolismo , Imidazóis/farmacologia , Córtex Renal/metabolismo , Córtex Renal/patologia , Losartan/farmacologia , Toxina Pertussis/farmacologia , Piridinas/farmacologia , Receptor Tipo 2 de Angiotensina/agonistas , Suínos
17.
Cancer Genet Cytogenet ; 151(1): 68-72, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15120912

RESUMO

We studied 58 childhood B-lineage acute lymphoblastic leukemia (B-ALL) in Brazilian sample patients at the time of diagnosis to investigate the prevalence of the cryptic t(12;21)(p13;q22). All bone marrow specimens were G-band karyotyped, and commercial dual-color DNA probes were used to search for fusion signals in nuclei. The karyotype analysis showed hyperdiploidy as the most frequent abnormality. The frequency of patients with TEL/AML1 gene fusion was 19% (11 out of 58 cases). Six of the positive samples had normal karyotypes. Deletion of the wild-type TEL allele was observed in 27.3% of TEL/AML1 fusion-positive cases, but it was also identified in 4.2% of the negative cases. Three cases presented two fusion signals, indicating possible duplication of the der(21). The mean age of the patients with TEL/AML1 fusion was 4.8 years and the mean amount of peripheral leukocytes was 44,270 x 10(6)/L. The higher frequency of females with B-ALL (33/58 cases) observed in our sample was probably due to the selection mode of the study cases. The prevalence of TEL/AML1 fusion in Brazilian children in our study is similar to that found in other populations.


Assuntos
Linfoma de Burkitt/genética , Proteínas de Fusão Oncogênica/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Brasil , Criança , Cromossomos Humanos Par 12 , Cromossomos Humanos Par 21 , Subunidade alfa 2 de Fator de Ligação ao Core , Feminino , Humanos , Hibridização in Situ Fluorescente , Cariotipagem , Masculino , Sondas Moleculares , Ploidias , Translocação Genética
18.
Regul Pept ; 117(1): 37-41, 2004 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-14687699

RESUMO

Recently, we demonstrated that bradykinin (BK) counteracts the stimulatory effect of Ang-(1-7) on the Na(+)-ATPase activity from basolateral membrane of the proximal tubule through B2 receptor. In the present paper, the signaling pathway involved in the inhibitory response of the Na(+)-ATPase activity to BK was investigated. The following results indicate that the phospholipase A2 (PLA2)/COX/prostaglandin E (PGE2) pathway is implicated in this process: (1) The inhibitory effect of BK on Ang-(1-7)-stimulated enzyme is abolished in a dose-dependent manner by quinacrine (10(-9)-10(-6)M), a nonspecific PLA2 inhibitor, and by PACOCF3 (10(-7)M), an inhibitor of a Ca(2+)-independent PLA2. However, AACOCF3 (2 x 10(-4) M), an inhibitor of the cytosolic PLA2, does not modify the inhibitory effect of BK. (2) The inhibitory effect of BK on the Ang-(1-7)-stimulated enzyme is reversed by cyclooxygenase (COX) inhibitors diclofenac (10(-12) M) and indomethacin (10(-12) M). (3) PGE2 (10(-12)-10(-5) M) inhibits the Na(+)-ATPase activity in a dose dependent manner. (4)The inhibitory effects of PGE2 and BK on the Na(+)-ATPase activity are not cumulative. (5) PGE2 (10(-12)-10(-8) M) counteracts the stimulatory effect of Ang-(1-7) on the enzyme activity in a dose-dependent manner.


Assuntos
Angiotensina I/farmacologia , Bradicinina/metabolismo , Dinoprostona/metabolismo , Túbulos Renais Proximais/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Fosfolipases A/metabolismo , ATPase Trocadora de Sódio-Potássio/metabolismo , Animais , Antagonistas de Receptor B2 da Bradicinina , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Inibidores de Ciclo-Oxigenase/metabolismo , Diclofenaco/metabolismo , Relação Dose-Resposta a Droga , Indometacina/metabolismo , Túbulos Renais Proximais/enzimologia , Fosfolipases A2 , Quinacrina/farmacologia , Receptor B2 da Bradicinina/metabolismo , Suínos
19.
Regul Pept ; 110(3): 207-12, 2003 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-12573801

RESUMO

Recently, we demonstrated that angiotensin-(1-7) (Ang-(1-7)) stimulates the Na(+)-ATPase activity through a losartan-sensitive angiotensin receptor, whereas bradykinin inhibits the enzyme activity through the B(2) receptor [Regul. Pept. 91 (2000) 45; Pharmacol. Rev. 32 (1980) 1]. In the present paper, the effect of bradykinin (BK) on Ang-(1-7)-stimulated Na(+)-ATPase activity was evaluated. Preincubation of Na(+)-ATPase with 10(-9) M Ang-(1-7) increases enzyme activity from 7.9+/-0.9 to 14.1+/-1.5 nmol Pi mg(-1) min(-1), corresponding to an increase of 79% (p<0.05). This effect is reverted by bradykinin in a dose-dependent manner (10(-14)-10(-8) M), reaching maximal inhibitory effect at 10(-9) M. Des-Arg(9) bradykinin (DABK), an agonist of B(1) receptor, at the concentrations of 10(-9)-10(-7) M, does not mimic the BK inhibitory effect, and des-Arg(9)-[Leu(8)]-BK (DALBK), a B(1) receptor antagonist, at the concentrations of 10(-10)-10(-7) M, does not prevent the inhibitory effect of BK on Ang-(1-7)-stimulated enzyme. On the other hand, HOE 140, an antagonist of B(2) receptor, abolishes the inhibitory effect of BK on the Ang-(1-7)-stimulated enzyme in a dose-dependent manner, reaching maximal effect at 10(-7) M. Taken together, these data indicate that stimulation of B(2) receptors by BK can counteract the stimulatory effect of Ang-(1-7) on the proximal tubule Na(+)-ATPase activity.


Assuntos
Adenosina Trifosfatases/metabolismo , Angiotensina I/antagonistas & inibidores , Angiotensina I/farmacologia , Bradicinina/metabolismo , Proteínas de Transporte de Cátions/metabolismo , Túbulos Renais Proximais/efeitos dos fármacos , Túbulos Renais Proximais/enzimologia , Fragmentos de Peptídeos/antagonistas & inibidores , Fragmentos de Peptídeos/farmacologia , Receptor B2 da Bradicinina/metabolismo , Animais , Antagonistas de Receptor B2 da Bradicinina , Suínos
20.
Rev Esc Enferm USP ; 35(2): 122-9, 2001 Jun.
Artigo em Português | MEDLINE | ID: mdl-12049047

RESUMO

This study discusses the functional method applied to Nursing, approached through a group dynamics developed with three groups of Master students from the University of São Paulo at Ribeirão Preto College of Nursing. After the dynamics, the subjects answered a questionnaire with four questions. The responses of the first group showed the limitations of the functional model that interfere in the work such as: impersonal relationships, fragmentation of tasks, centralization of decisions causing the workers' dissatisfaction. The groups II and III pointed out some advantages when the work is based on a team, such as the exchange of experiences, participant planning and shared decisions, resulting in satisfaction at work.


Assuntos
Processos Grupais , Enfermagem/métodos , Prática Profissional , Educação em Enfermagem
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