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1.
J Biol Regul Homeost Agents ; 35(2 Suppl. 1): 139-145, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34281310

RESUMO

The route of transmission of SARS-CoV-2 has been understood thanks to the knowledge of previously identified human coronaviruses. According to these studies, the transmission of the virus occurs mainly between humans at close range, through respiratory droplets produced during conversation or coughing, as well as through direct contact of the hands then placed on the mucous membranes or mouth. From the final analysis of studies carried out on protective systems, the validity of plexiglass as a material to be used for the construction of protective devices could be affirmed. The plexiglass, in fact, would seem able to isolate the diffusion of aerosol particles dispersed by infected subjects and in different environments.


Assuntos
COVID-19 , Polimetil Metacrilato , Aerossóis , Tosse , Humanos , SARS-CoV-2
2.
Ultrasound Obstet Gynecol ; 47(6): 726-31, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26053472

RESUMO

OBJECTIVE: To compare first-trimester uterine artery pulsatility index (UtA-PI) and three-dimensional (3D) placental volume in pregnancies conceived through in-vitro fertilization (IVF) using autologous or donor oocytes and pregnancies conceived naturally, and to relate these measurements to the development of pre-eclampsia (PE). METHODS: UtA-PI and placental volume were measured at 11 + 0 to 13 + 6 weeks of gestation in 416 IVF pregnancies (307 with autologous and 109 with donor oocytes) and in 498 spontaneously conceived pregnancies. We recruited nulliparous women with singleton pregnancy. The measured mean UtA-PI and placental volume values were converted to multiples of the expected normal median (MoM), adjusted for gestational age. MoM values of IVF pregnancies were compared with MoM values of the naturally conceived pregnancies and related to PE development. RESULTS: Placental volume was significantly reduced in IVF pregnancies (K = 169.3; P < 0.0001) compared with natural pregnancies. No difference was found in UtA-PI MoM between the two groups. Among IVF pregnancies, significantly lower placental volumes were seen in those that received donor oocytes when compared with those with autologous oocytes (z = 3.89; P < 0.001). In IVF pregnancies that developed PE, lower values of placental volume were demonstrated with respect to normotensive pregnancies (donor: U = 6.8; P = 0.009; autologous: U = 5.1; P = 0.023), whereas no difference was found in UtA-PI. Multivariate logistic regression analysis demonstrated that placental volume (odds ratio (OR), 1.97 (95% CI, 1.33-2.27)) and donor oocytes in IVF pregnancy (OR, 2.24 (95% CI, 1.5-2.83)) were independent predictors of PE, whereas autologous oocytes in IVF pregnancy were not found to be significant in the model. CONCLUSIONS: First-trimester placental volume, as assessed by 3D ultrasound, is reduced in IVF pregnancies and this reduction is more marked in those involving donor oocyte recipients. The relative decrease in placental volume in IVF pregnancies that developed PE suggests an etiological mechanism different from uterine perfusion in such patients. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Ultrassonografia Pré-Natal/métodos , Artéria Uterina/diagnóstico por imagem , Útero/irrigação sanguínea , Adulto , Feminino , Fertilização in vitro , Idade Gestacional , Humanos , Pessoa de Meia-Idade , Doação de Oócitos , Gravidez , Adulto Jovem
3.
Ultrasound Obstet Gynecol ; 48(4): 511-515, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26565728

RESUMO

OBJECTIVE: To determine whether the subpubic arch angle (SPA) measured by three-dimensional ultrasound is associated with the fetal occiput position at delivery and the mode of delivery. METHODS: Nulliparous women with an uncomplicated singleton pregnancy at ≥ 37 weeks' gestation were recruited from two tertiary centers between September 2013 and August 2015. All women underwent a three-dimensional transperineal ultrasound examination and the SPA was measured using the previously validated Oblique View Extended Imaging software. Data on the outcome of labor were obtained prospectively in all cases and the correlations between SPA and the fetal occiput position at delivery and the incidence of operative delivery were investigated. RESULTS: Overall, 368 women were included in the study. Fetal position at delivery was occiput anterior in 339 (92.1%) cases and occiput posterior (OP) in 29 (7.9%) cases. A significantly narrower SPA was found in the OP group compared with the occiput anterior group (104.4 ± 16.8° vs 116.4 ± 11.9°; P < 0.0001). The SPA was significantly narrower in women requiring obstetric intervention compared with in women with a spontaneous vaginal delivery. From multivariable logistic regression analysis, SPA and maternal height appeared to be significant predictors of both the fetal occiput position at delivery and the risk of operative delivery. The best cut-off value of SPA for predicting an OP position at delivery was 90.5°. CONCLUSION: A narrow SPA is associated with a higher risk of persistent OP position at delivery and of operative delivery. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Parto Obstétrico/métodos , Pelve/anatomia & histologia , Ultrassonografia Pré-Natal/métodos , Adulto , Feminino , Humanos , Imageamento Tridimensional/métodos , Apresentação no Trabalho de Parto , Pelve/diagnóstico por imagem , Gravidez , Estudos Prospectivos
5.
Ultrasound Obstet Gynecol ; 44(5): 557-61, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24585633

RESUMO

OBJECTIVES: To compare uterine artery pulsatility index (PI) obtained at 11 + 0 to 13 + 6 weeks of gestation in singleton and twin pregnancies and to evaluate changes in PI values of twin pregnancies developing pre-eclampsia (PE) or small-for-gestational age (SGA) of either one or both fetuses. METHODS: Uterine artery PI was measured in 421 twin pregnancies (384 dichorionic and 37 monochorionic) and in 500 singleton pregnancies. The measured mean and lowest uterine artery PI values were converted to multiples of the expected normal median (MoM) after correction for maternal body mass index, ethnicity and gestational age. The median PI-MoM values of twins were compared with those of singleton pregnancies. In twin pregnancies, PI-MoM values were analyzed according to chorionicity, development of early-onset (< 34 weeks) or late-onset (≥ 34 weeks) PE and SGA of one or both twins. RESULTS: Uterine artery PI-MoM was significantly lower in twin compared with singleton pregnancies (mean K = 174.31, P < 0.0001, lowest K = 139.27, P < 0.0001). However, there were no significant differences in the uterine artery PI-MoM values between monochorionic and dichorionic twins. The uterine artery PI in twin pregnancies that developed early-onset PE (P < 0.001) and SGA of both twins (P < 0.05) was higher than the uterine artery PI in uncomplicated twin pregnancies, whereas no differences were found for late PE or SGA of one twin. CONCLUSIONS: First-trimester placental impedance to flow, as assessed by uterine artery Doppler examination, is reduced in twin pregnancies, with no differences related to chorionicity. The relative increase of uterine artery PI found in twin pregnancies that developed early PE and SGA of both twins suggests that first-trimester uterine artery assessment may be useful in identifying such complications.


Assuntos
Recém-Nascido Pequeno para a Idade Gestacional/fisiologia , Pré-Eclâmpsia/fisiopatologia , Gravidez de Gêmeos/fisiologia , Artéria Uterina/fisiologia , Adolescente , Adulto , Velocidade do Fluxo Sanguíneo/fisiologia , Estudos de Casos e Controles , Feminino , Retardo do Crescimento Fetal/diagnóstico por imagem , Retardo do Crescimento Fetal/fisiopatologia , Idade Gestacional , Humanos , Idade Materna , Pré-Eclâmpsia/diagnóstico por imagem , Gravidez , Resultado da Gravidez , Primeiro Trimestre da Gravidez , Fluxo Pulsátil , Gêmeos Dizigóticos , Gêmeos Monozigóticos , Ultrassonografia Doppler , Ultrassonografia Pré-Natal , Adulto Jovem
6.
Life Sci ; 312: 121219, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36435222

RESUMO

Two alkalinizing mechanisms coexist in cardiac myocytes to maintain intracellular pH: sodium/bicarbonate cotransporter (electroneutral isoform NBCn1 and electrogenic isoform NBCe1) and sodium/proton exchanger (NHE1). Dysfunction of these transporters has previously been reported to be responsible for the development of cardiovascular diseases. The aim of this study was to evaluate the contribution of the downregulation of the NBCe1 to the development of cardiac hypertrophy. To specifically reduce NBCe1 expression, we cloned shRNA into a cardiotropic adeno-associated vector (AAV9-shNBCe1). After 28 days of being injected with AAV9-shNBCe1, the expression and the activity of NBCe1 in the rat heart were reduced. Strikingly, downregulation of NBCe1 causes significant hypertrophic heart growth, lengthening of the action potential in isolated myocytes, an increase in the duration of the QT interval and an increase in the frequency of Ca2+ waves without any significant changes in Ca2+ transients. An increased compensatory expression of NBCn1 and NHE1 was also observed. We conclude that reduction of NBCe1 is sufficient to induce cardiac hypertrophy and modify the electrical features of the rat heart.


Assuntos
Bicarbonatos , Simportadores de Sódio-Bicarbonato , Ratos , Animais , Simportadores de Sódio-Bicarbonato/genética , Simportadores de Sódio-Bicarbonato/metabolismo , Bicarbonatos/metabolismo , Cardiomegalia/genética , Cardiomegalia/metabolismo , Sódio/metabolismo , Isoformas de Proteínas/metabolismo , Concentração de Íons de Hidrogênio
7.
Euro Surveill ; 17(33)2012 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-22913976

RESUMO

Carbapenem-resistant Klebsiella pneumoniae has recently been reported as a new, multidrug-resistant nosocomial pathogen in several hospitals from various Italian regions. Through Micronet, a new Italian sentinel laboratory-based surveillance network, we studied the trend of non-susceptibility of K. pneumoniae to selected carbapenems (imipenem and/or meropenem) in 14 of the 15 hospitals participating in the network. Analysis of data from 1 January 2009 to 30 April 2012 revealed a statistically significant increasing trend (p<0.01) in the proportion of carbapenem non-susceptible K. pneumoniae isolates from clinical specimens (from 2.2 % in 2009 to 19.4% in 2012). The increase in the proportion of non-susceptibility was very large for isolates from the respiratory tract (from 5.3% in 2009 to 38.5% in 2012) and blood (from 5.4% in 2009 to 29.2% in 2012). The results demonstrate the urgent need in Italy for infection control, guidelines, antibiotic stewardship programmes and utilisation of surveillance systems, such as Micronet, which are capable of receiving data from hospitals in real time for many pathogens and types of clinical specimens.


Assuntos
Antibacterianos/farmacologia , Carbapenêmicos/farmacologia , Farmacorresistência Bacteriana , Infecções por Klebsiella/tratamento farmacológico , Klebsiella pneumoniae/efeitos dos fármacos , Hospitais , Humanos , Imipenem/farmacologia , Itália , Klebsiella pneumoniae/isolamento & purificação , Meropeném , Testes de Sensibilidade Microbiana/tendências , Vigilância de Evento Sentinela , Tienamicinas/farmacologia
8.
Ultrasound Obstet Gynecol ; 38(2): 158-64, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21305636

RESUMO

OBJECTIVE: To describe a novel algorithm, based on the new display technology 'OmniView', developed to visualize diagnostic sagittal and coronal planes of the fetal brain from volumes obtained by three-dimensional (3D) ultrasonography. METHODS: We developed an algorithm to image standard neurosonographic planes by drawing dissecting lines through the axial transventricular view of 3D volume datasets acquired transabdominally. The algorithm was tested on 106 normal fetuses at 18-24 weeks of gestation and the visualization rates of brain diagnostic planes were evaluated by two independent reviewers. The algorithm was also applied to nine cases with proven brain defects. RESULTS: The two reviewers, using the algorithm on normal fetuses, found satisfactory images with visualization rates ranging between 71.7% and 96.2% for sagittal planes and between 76.4% and 90.6% for coronal planes. The agreement rate between the two reviewers, as expressed by Cohen's kappa coefficient, was > 0.93 for sagittal planes and > 0.89 for coronal planes. All nine abnormal volumes were identified by a single observer from among a series including normal brains, and eight of these nine cases were diagnosed correctly. CONCLUSIONS: This novel algorithm can be used to visualize standard sagittal and coronal planes in the fetal brain. This approach may simplify the examination of the fetal brain and reduce dependency of success on operator skill.


Assuntos
Algoritmos , Encéfalo/patologia , Doenças do Sistema Nervoso Central/diagnóstico por imagem , Doenças do Sistema Nervoso Central/patologia , Imageamento Tridimensional/métodos , Ultrassonografia Pré-Natal/métodos , Adolescente , Adulto , Encéfalo/anatomia & histologia , Encéfalo/embriologia , Feminino , Humanos , Aumento da Imagem , Pessoa de Meia-Idade , Gravidez , Segundo Trimestre da Gravidez , Adulto Jovem
9.
Minerva Ginecol ; 63(5): 401-10, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21926949

RESUMO

The objective of this review was to establish whether three-dimensional (3D) and four dimensional (4D) ultrasonography adds diagnostic information to what is currently provided by two-dimensional (2D) ultrasound in the diagnosis of the most frequent fetal structural defects: congenital heart disease and central nervous system congenital anomalies. There are evidences suggesting that 3D ultrasound allows to reduce the operator dependency in the visualization of standard diagnostic planes, thus reducing the examination time require for the obstetric ultrasound examination, with minimal impact on the visualization quality of the anatomic landmarks. Furthermore, operators with minimal experience may record cardiac or brain volumes that can be successfully analyzed off-line locally or sent by internet to experts for remote review. As a consequence 3D ultrasonography promises to become the method of choice for diagnosis congenital structural defects.


Assuntos
Ecocardiografia Tridimensional/métodos , Cardiopatias Congênitas/diagnóstico por imagem , Malformações do Sistema Nervoso/diagnóstico por imagem , Ultrassonografia Pré-Natal , Ecocardiografia Quadridimensional/métodos , Feminino , Humanos , Valor Preditivo dos Testes , Gravidez , Sensibilidade e Especificidade , Ultrassonografia Pré-Natal/métodos
10.
Hipertens Riesgo Vasc ; 37(4): 169-175, 2020.
Artigo em Espanhol | MEDLINE | ID: mdl-32527699

RESUMO

The first case of COVID-19 was reported on 31 December 2019 in Wuhan, China. Ever since there has been unprecedented and growing interest in learning about all aspects of this new disease. Debate has been generated as to the association between antihypertensive therapy with renin-angiotensin-aldosterone system (RAAS) inhibitors and SARS-CoV-2 infection. While many questions as yet remain unanswered, the aim of this report is to inform health professionals about the current state of knowledge. Because this is an ever-evolving topic, the recommendation is that it be updated as new evidence becomes available. Below, we provide a review of pre-clinical and clinical studies that link coronavirus to the RAAS.


Assuntos
Betacoronavirus , Infecções por Coronavirus/fisiopatologia , Pandemias , Pneumonia Viral/fisiopatologia , Sistema Renina-Angiotensina/fisiologia , Proteína ADAM17/fisiologia , Angiotensina II/fisiologia , Antagonistas de Receptores de Angiotensina/efeitos adversos , Antagonistas de Receptores de Angiotensina/farmacologia , Antagonistas de Receptores de Angiotensina/uso terapêutico , Enzima de Conversão de Angiotensina 2 , Inibidores da Enzima Conversora de Angiotensina/efeitos adversos , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Anti-Hipertensivos/efeitos adversos , Anti-Hipertensivos/farmacologia , Anti-Hipertensivos/uso terapêutico , COVID-19 , Vacinas contra COVID-19 , Infecções por Coronavirus/complicações , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Humanos , Hipertensão/complicações , Hipertensão/fisiopatologia , Pulmão/fisiopatologia , Modelos Biológicos , Pandemias/prevenção & controle , Peptidil Dipeptidase A/efeitos dos fármacos , Peptidil Dipeptidase A/fisiologia , Pneumonia Viral/complicações , Pneumonia Viral/imunologia , Pneumonia Viral/prevenção & controle , Receptores Virais/efeitos dos fármacos , Sistema Renina-Angiotensina/efeitos dos fármacos , Síndrome do Desconforto Respiratório/etiologia , Síndrome do Desconforto Respiratório/fisiopatologia , SARS-CoV-2 , Serina Endopeptidases/fisiologia , Vacinas Virais , Internalização do Vírus/efeitos dos fármacos
11.
Gait Posture ; 78: 13-18, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32171169

RESUMO

BACKGROUND: Contralateral strength training (CST) is increasingly investigated and employed as a non-conventional way to induce an indirect gain in strength in the weakened untrained limb. However, its effects on gait performance are more controversial. RESEARCH QUESTION: To assess and compare the effects of contralateral (CST) and direct (DST) strength training on spatio-temporal parameters, kinematic and kinetic descriptors of gait in persons with relapsing-remitting multiple sclerosis (PwMS). METHODS: Twenty-eight PwMS (EDSS 2.0-5.5) with inter-side difference in ankle dorsiflexors' strength ≥ 20 % and moderate gait impairment (walking speed 0.70-0.94 m/s), were randomly assigned to a CST (undergoing training of the less-affected dorsiflexors) or DST group (where the most-affected dorsiflexors were trained). Before and after a 6-week high-intensity resistance training (three 25-minute sessions/week), PwMS underwent bilateral measurements of dorsiflexors' maximal strength and assessment of gait spatio-temporal parameters, lower limb joint kinematics and kinetics. RESULTS AND SIGNIFICANCE: Following the training period, muscle strength increased significantly in both groups (on average, CST + 29.5 %, p < 0.0005; DST + 15.7 %, p = 0.001) with no difference between the two interventions. Significant changes in gait speed (+16.5 %; p < 0.0001) and stride length (+6.0 %; p = 0.04) were detected only after DST, while no difference was detected in the CST group. Ankle moment and ROM were unaffected by the training. In PwMS with mild to moderate disability and lower limb dorsiflexors' strength asymmetry, CST was not inferior to DST in inducing significant strength gains in the untrained most-affected limb. However, only DST significantly improved gait performance and, specifically, walking speed. Even though CST did not worsen asymmetry, data suggest that contralateral approaches should not be recommended straightaway if the training goal is to improve outcomes other than strength and, specifically, walking speed.


Assuntos
Terapia por Exercício/métodos , Marcha , Esclerose Múltipla Recidivante-Remitente/terapia , Treinamento Resistido/métodos , Adulto , Articulação do Tornozelo , Fenômenos Biomecânicos , Feminino , Humanos , Extremidade Inferior , Masculino , Pessoa de Meia-Idade , Força Muscular , Projetos Piloto , Amplitude de Movimento Articular , Velocidade de Caminhada
12.
Clin Ter ; 171(3): e197-e208, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32323706

RESUMO

PURPOSE: Stress is a multifactorial and complex pathway, gaining growing attention from the healthcare community. Surgeons are subjected to higher levels of stress, due to surgical procedures that are demanding and repetitive; unfortunately, high-stress levels may also cause side-effects, as surgical mistakes. This study aimed to evaluate the efficacy of specific probiotics strains formula on stress levels in oral and maxillofacial surgeons, to improve their quality of life. METHODS: We have investigated the hormonal (salivary Cortisol; sC), immune (salivary Immunoglobulin A; sIgA) and cardiovascular (Heart rate, HR, and systolic blood pressure, SBP) responses induced by stress conditions in 40 oral surgeons, randomly selected and allocated, according to their experience level, in three categories: senior, expert, and junior. RESULTS: The results described how the number of heartbeats/ minute and SBP are slightly raised in all surgeons at different timepoints. Such data allow us to assess that work-related stress can induce an increase in cardiovascular parameters, even if they are not significantly modified by the use of probiotics. On the other hand, our data indicate that 10 weeks of probiotic integration may induce the improvement of other stress-related physiological parameters in oral surgeons with different degrees of surgical experience, such as the salivary cortisol levels, even under stress conditions. Moreover, in the test group (probiotics administration), the immunoglobulin levels were higher than the control (placebo administration) group: this happens as a consequence of the regular use of probiotics, which may induce an increased number of IgA producing cells. DISCUSSION: Our data indicated that 10 weeks of probiotics-enriched diet modify some stress-related physiological parameters in oral surgeons with different degrees of surgical experience, but it does not impact on the overall cardiovascular risk.


Assuntos
Cirurgiões Bucomaxilofaciais/psicologia , Probióticos/uso terapêutico , Estresse Fisiológico/efeitos dos fármacos , Adulto , Pressão Sanguínea , Competência Clínica , Método Duplo-Cego , Frequência Cardíaca , Humanos , Hidrocortisona/metabolismo , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Saliva/metabolismo
13.
J Cell Biol ; 54(3): 493-506, 1972 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-5044757

RESUMO

The form of beat of cilia and the structure of the metachronal wave on the lateral gill epithelium of Mytulus edulis have been studied on living material by interference-contrast microscopy and stroboscopic illumination, and compared with the same features in rapid-fixed preparations studied by light microscopy and with the scanning electron microscope. The most striking finding is that the beat of the cilia is not planar, as previously assumed, but involves a sideways movement in the recovery stroke Previous reports on nonplanar ciliary beating from protozoan examples describe a planar effective stroke and a counterclockwise rotation in the recovery stroke; in this molluscan example there is a clockwise rotation in the recovery stroke The lateral inclination of the cilia in the recovery stroke is in the same direction as the propagation of the waves, and the orientation of cilia in the recovery stroke is thought to determine whether the waves move to the left or right of the direction of the effective stroke


Assuntos
Cílios/fisiologia , Brânquias/fisiologia , Animais , Fenômenos Biomecânicos , Células Epiteliais , Epitélio/fisiologia , Brânquias/citologia , Microscopia Eletrônica de Varredura , Microscopia de Interferência , Modelos Estruturais , Músculos/fisiologia , Rotação
14.
Science ; 194(4264): 539-41, 1976 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-973139

RESUMO

Treatment of the mussel Mytilus edulis with 6-hydroxydopamine or with alpha-methyl-p-tyrosine decreased dopamine and increased serotonin in the nervous system. Treatment with dopamine decreased serotonin concentrations and prevented the effect of 6-hydroxydopamine. The serotonin concentration appears to be determined in part by the concentration of dopamine.


Assuntos
Dopamina/metabolismo , Neurônios/metabolismo , Animais , Bivalves , Dopamina/farmacologia , Gânglios , Brânquias/inervação , Histocitoquímica , Hidroxidopaminas/farmacologia , Metiltirosinas/farmacologia
15.
Life Sci ; 83(7-8): 264-71, 2008 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-18625248

RESUMO

We have previously demonstrated the participation of reactive oxygen species (ROS) in the positive inotropic effect of a physiological concentration of Angiotensin II (Ang II, 1 nM). The objective of the present work was to evaluate the role and source of ROS generation in the positive inotropic effect produced by an equipotent concentration of endothelin-1 (ET-1, 0.4 nM). Isolated cat ventricular myocytes were used to measure sarcomere shortening with a video-camera, superoxide anion (()O(2)(-)) with chemiluminescence, and ROS production and intracellular pH (pH(i)) with epifluorescence. The ET-1-induced positive inotropic effect (40.4+/-3.1%, n=10, p<0.05) was associated to an increase in ROS production (105+/-29 fluorescence units above control, n=6, p<0.05). ET-1 also induced an increase in ()O(2)(-) production that was inhibited by the NADPH oxidase blocker, apocynin, and by the blockers of mitochondrial ATP-sensitive K(+) channels (mK(ATP)), glibenclamide and 5 hydroxydecanoic acid. The ET-1-induced positive inotropic effect was inhibited by apocynin (0.3 mM; 6.3+/-6.6%, n=13), glibenclamide (50 microM; 8.8+/-3.5%, n=6), 5 hydroxydecanoic acid (500 microM; 14.1+/-8.1, n=9), and by scavenging ROS with MPG (2 mM; 0.92+/-5.6%, n=8). ET-1 enhanced proton efflux (J(H)) carried by the Na(+)/H(+) exchanger (NHE) after an acid load, effect that was blocked by MPG. Consistently, the ET-induced positive inotropic effect was also inhibited by the NHE selective blocker HOE642 (5 microM; 9.37+/-6.07%, n=7). The data show that the effect of a concentration of ET-1 that induces an increase in contractility of about 40% is totally mediated by an intracellular pathway triggered by mitochondrial ROS formation and stimulation of the NHE.


Assuntos
Cardiotônicos/farmacologia , Endotelina-1/farmacologia , Mitocôndrias Cardíacas/metabolismo , Miócitos Cardíacos/metabolismo , Superóxidos/metabolismo , Angiotensina II/antagonistas & inibidores , Angiotensina II/farmacologia , Animais , Cardiotônicos/antagonistas & inibidores , Gatos , Células Cultivadas , Relação Dose-Resposta a Droga , Endotelina-1/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Sequestradores de Radicais Livres/farmacologia , Glicina/análogos & derivados , Glicina/farmacologia , Ventrículos do Coração/citologia , Ventrículos do Coração/metabolismo , Contração Miocárdica/efeitos dos fármacos , Miócitos Cardíacos/citologia , NADPH Oxidases/antagonistas & inibidores , NADPH Oxidases/metabolismo , Bloqueadores dos Canais de Potássio/farmacologia , Canais de Potássio/metabolismo , Sarcômeros/metabolismo , Trocadores de Sódio-Hidrogênio/antagonistas & inibidores , Trocadores de Sódio-Hidrogênio/metabolismo , Compostos de Sulfidrila/farmacologia , Superóxidos/antagonistas & inibidores , Vasoconstritores/antagonistas & inibidores , Vasoconstritores/farmacologia
17.
Oncol Rep ; 4(2): 341-3, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-21590055

RESUMO

Folk medicine has attributed antitumor properties to preparations from Aloe vera. We have studied the effects of five purified compounds from the plant on human K562 leukemia and on its multidrug resistant (MDR) variant, K562/R. The glycosides aloin A and B, aloesin and aloeresin were devoid of antitumor activity up to 200 mu M concentrations. Only the aglycone aloe emodin produced reproducible antitumor effects, which, interestingly, were more pronounced in the MDR, P-glycoprotein overexpressing, cell line. Its IC50 was in fact 29 mu M in K562 and 10.5 mu M in K562/R. Aloe emodine caused mainly cytostasis and accumulation of the cells in the S and G(2)-M phases of the cell cycle during the first 48 h of treatment. Thereafter, massive cell death ensued. Research on the antitumor activity of compounds extracted from Aloe vera probably deserves continuation.

18.
Farmaco ; 47(12): 1555-62, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1294170

RESUMO

3-Diazo-2-phenylpyrroles 3a-g showed antimicrobial activity against Gram-positive bacteria, whereas against Gram-negative strains the inhibitory activity is limited to derivatives 3a and 3c. The substituents at 4 and 5 positions strongly influence the inhibitory activity, but the presence of the diazo group is crucial for appearance of activity.


Assuntos
Antibacterianos/síntese química , Pirróis/síntese química , Antibacterianos/farmacologia , Fenômenos Químicos , Físico-Química , Escherichia coli/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Pirróis/farmacologia , Espectrofotometria Ultravioleta , Streptomyces/efeitos dos fármacos
19.
Farmaco ; 50(12): 849-52, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8634075

RESUMO

Indolo[3,2-c]cinnolines of type 5, variously substituted either in the indole and in the cinnoline moieties, were prepared in good overall yields, by intramolecular cyclization of indolo derivatives 4. Compounds 5a-d showed a good cytotoxic activity against FLC and K562 leukemic cell lines, both sensitive and multi-drug resistant.


Assuntos
Antineoplásicos/síntese química , Compostos Heterocíclicos/síntese química , Leucemia/tratamento farmacológico , Antineoplásicos/farmacologia , Humanos , Células Tumorais Cultivadas
20.
Farmaco ; 50(6): 365-8, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7669175

RESUMO

Pyrrolo-, pyrazolo- and triazolo-phenanthridines were synthetized by using a Pschorrtype cyclization reaction or an intramolecular cyclization of arylnitrenium ions. By using these synthetic methods several azolo-phenanthridines, variously functionalized either in the azolo ring and in the phenanthridine moiety, were prepared. The title compounds, tested against murine leukemia cell lines, sensible and multidrug resistant, showed moderate activity with IC50 in the range 5-50 microM.


Assuntos
Antineoplásicos/síntese química , Fenantridinas/síntese química , Animais , Antineoplásicos/farmacologia , Humanos , Fenantridinas/farmacologia
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