In vitro assessment of a computer-designed potential anticancer agent in cervical cancer cells

BACKGROUND: Computer-based technology is becoming increasingly essential in biological research where drug discovery programs start with the identification of suitable drug targets. 2-Methoxyestradiol (2ME2) is a 17ß-estradiol metabolite that induces apoptosis in various cancer cell lines including cervical cancer, breast cancer and multiple myeloma. Owing to 2ME2's poor in vivo bioavailability, our laboratory in silico-designed and subsequently synthesized a novel 2ME2 analogue, 2-ethyl-3-O-sulphamoyl-estra-1,3,5(10),15-tetraen-17-ol (ESE-15-ol), using receptor- and ligand molecular modeling. In this study, the biological effects of ESE-15-ol (180 nM) and its parent molecule, 2ME2 (1 µM), were assessed on morphology and apoptosis induction in cervical cancer cells. RESULTS: Transmission electron microscopy, scanning electron microscopy and polarization-optical transmitted light differential interference contrast (PlasDIC) images demonstrated morphological hallmarks of apoptosis including apoptotic bodies, shrunken cells, vacuoles, reduced cell density and cell debris. Flow cytometry analysis showed apoptosis induction by means of annexin V-FITC staining. Cell cycle analysis showed that ESE-15-ol exposure resulted in a statistically significant increase in the G2M phase (72%) compared to 2ME2 (19%). Apoptosis induction was more pronounced when cells were exposed to ESE-15-ol compared to 2ME2. Spectrophotometric analysis of caspase 8 activity demonstrated that 2ME2 and ESE-15-ol both induced caspase 8 activation by 2- and 1.7-fold respectively indicating the induction of the apoptosis. However, ESE-15-ol exerted all of the above-mentioned effects at a much lower pharmacological concentration (180 nM) compared to 2ME2 (1 µM physiological concentration). CONCLUSION: Computer-based technology is essential in drug discovery and together with in vitro studies for the evaluation of these in silico-designed compounds, drug development can be improved to be cost effective and time consuming. This study evaluated the anticancer potential of ESE-15-ol, an in silico-designed compound in vitro. Research demonstrated that ESE-15-ol exerts antiproliferative activity accompanied with apoptosis induction at a nanomolar concentration compared to the micromolar range required by 2ME2. This study is the first study to demonstrate the influence of ESE-15-ol on morphology, cell cycle progression and apoptosis induction in HeLa cells. In silico-design by means of receptor- and ligand molecular modeling is thus effective in improving compound bioavailability while preserving apoptotic activity in vitro.

Knowledge and practice of Brazilian pediatricians on gastroesophageal reflux disease in infants / Conhecimento e prática de pediatras brasileiros sobre a doença do refluxo gastroesofágico em lactentes

OBJECTIVE: To assess the knowledge and practice of pediatricians about infants with physiological reflux and gastroesophageal reflux disease. METHODS: 140 pediatricians were interviewed during two scientific events in 2009 and 2010. The questions referred to two clinical cases of infants. One with symptoms of infant regurgitation (physiological reflux) and another with gastroesophageal reflux disease. RESULTS: Among 140 pediatricians, 11.4% (n=16) and 62.1% (n=87) would require investigation tests, respectively for infant regurgitation (physiological reflux) and gastroesophageal reflux disease. A series of upper gastrointestinal exams would be the first requested with a higher frequency. Medication would be prescribed by 18.6% (n=6) in the case of physiological reflux and 87.1% (n=122) in the case of gastroesophageal reflux disease. Prokinetic drugs would be prescribed more frequently than gastric acid secretion inhibitors. Sleeping position would be recommended by 94.2% (n=132) and 92.9% (n=130) of the respondents, respectively for the case of physiological reflux and gastroesophageal reflux disease; however, about half of the respondents would recommend the prone position. Only 10 (7.1%) of the pediatricians would exclude the cow's milk protein from the infants' diet. CONCLUSIONS: Approaches different from the international guidelines are often considered appropriate, especially when recommending a different position other than the supine and prescription of medication. In turn, the interviews enable us to infer the right capacity of the pediatricians to distinguish physiologic reflux and gastroesophageal reflux disease correctly. .

OBJETIVO: Avaliar o conhecimento e a prática de pediatras brasileiros na assistência ao lactente com refluxo fisiológico e doença do refluxo gastroesofágico. MÉTODOS: Foram entrevistados 140 médicos pediatras em dois eventos científicos em 2009 e 2010. As perguntas referiam-se a dois casos clínicos de lactentes, um com quadro compatível com regurgitação do lactente (refluxo fisiológico) e outro com doença do refluxo gastroesofágico. RESULTADOS: Dos 140 participantes, 11,4% (n=16) e 62,1% (n=87) solicitariam exame para lactentes, respectivamente, com refluxo fisiológico e doença do refluxo gastroesofágico. O primeiro exame solicitado com maior frequência seria a radiografia contrastada de esôfago, estômago e duodeno. Medicação seria prescrita por 18,6% (n=26) para o caso de refluxo fisiológico e 87,1% (n=122) para o caso de doença do refluxo gastroesofágico. Procinéticos seriam prescritos com maior frequência do que os redutores da secreção ácida gástrica. Prescrição de posição para dormir fez parte das recomendações de 94,2% (n=132) e 92,9% (n=130) dos entrevistados, respectivamente, para os casos de refluxo fisiológico e doença do refluxo gastroesofágico. Entretanto, cerca da metade dos entrevistados não recomendaria o decúbito dorsal. Prescrição de dieta de exclusão do leite de vaca para um lactente com quadro de doença do refluxo gastroesofágico seria feita por apenas 10 (7,1%) dos participantes. CONCLUSÕES: Condutas diferentes das diretrizes internacionais são frequentemente consideradas adequadas, especialmente quanto à recomendação de posição diferente do decúbito dorsal e prescrição de medicamentos. As respostas permitem inferir a capacidade de correta diferenciação entre refluxo fisiológico e doença do refluxo gastroesofágico. .

Ultrastructural changes of erythrocytes in whole blood after exposure to prospective in silico-designed anticancer agents: a qualitative case study

BACKGROUND: Novel, in silico-designed anticancer compounds were synthesized in our laboratory namely, 2-ethyl-3-O-sulphamoyl-estra-1,3,5(10),15-tetraen-17-ol (ESE-15-ol) and 2-ethyl-3-O-sulphamoyl-estra-1,3,5(10)16-tetraene (ESE-16). These compounds were designed to have improved bioavailability when compared to their source compound, 2-methoxyestradiol. This theoretically would be due to their increased binding affinity to carbonic anhydrase II, present in erythrocytes. Since the novel compounds under investigation are proposed to be transported within erythrocytes bound to carbonic anhydrase II, the morphological effect which they may exert on whole blood and erythrocytes is of great significance. A secondary outcome included revision of previously reported procedures for the handling of the whole blood sample. The purpose of this study was twofold. Firstly, the ultrastructural morphology of a healthy female's erythrocytes was examined via scanning electron microscopy (SEM) after exposure to the newly in silico-designed compounds. Morphology of erythrocytes following exposure to ESE-15-ol and ESE-16 for 3 minutes and 24 hours at 22°C were described with the use of SEM. The haemolytic activity of the compounds after 24 hours exposure were also determined with the ex vivo haemolysis assay. Secondly, storage conditions of the whole blood sample were investigated by determining morphological changes after a 24 hour storage period at 22°C and 37°C. RESULTS: No significant morphological changes were observed in the erythrocyte morphology after exposure to the novel anticancer compounds. Storage of the whole blood samples at 37°C for 24 hours resulted in visible morphological stress in the erythrocytes. Erythrocytes incubated at 22°C for 24 hours showed no structural deformity or distress. CONCLUSIONS: From this research the optimal temperature for ex vivo exposure of whole blood samples to ESE-15-ol and ESE-16 for 24 hours was determined to be 22°C. Data from this study revealed the potential of these compounds to be applied to ex vivo study techniques, since no damage occurred to erythrocytes ultrastructure under these conditions. As no structural changes were observed in erythrocytes exposed to ESE-15-ol and ESE-16, further ex vivo experiments will be conducted into the potential effects of these compounds on whole blood. Optimal incubation conditions up to 24 hours for whole blood were established as a secondary outcome.

Prospecção de atividade inibitória da pasta de hidróxido de cálcio e acetazolamida sobre Enterococcus faecalis e Candida albicans / Antimicrobial effect of calcium hydroxide paste and acetazolamide against the Enterococcus faecalis and Candida albicans

Introdução: A medicação intracanal é fundamental para o tratamento de um dente avulsionado, sendo a pasta de hidróxido de cálcio comumente indicada. A acetazolamida é uma substância inibidora da anidrase carbônica e da reabsorção óssea, podendo ser sugerida como medicação intracanal em dentes avulsionados. Contudo, para que uma substância seja sugerida, estudos devem comprovar sua eficácia tanto in vitro como in vivo. Objetivo: Avaliar in vitro a ação antimicrobiana da pasta de hidróxido de cálcio e da acetazolamida, associadas a diferentes veículos, contra os micro-organismos Enterococcus faecalis e Candida albicans. Materiais e métodos: As formulações selecionadas foram: acetazolamida (pó) com soro fisiológico; acetazolamida (pó) com glicerina; acetazolamida e hidróxido de cálcio (pó) em porções iguais com soro fisiológico; acetazolamida e hidróxido de cálcio (pó) em porções iguais adicionando-se glicerina; acetazolamida (líquido) e hidróxido de cálcio (pó) com soro fisiológico. Como controle positivo foram utilizadas concentrações de clorexidina de 20%, 10%, 5%, 2,5%, 1,25% e 0,65% e como controle negativo a glicerina. O experimento foi realizado por teste de difusão em ágar. Resultados: Não houve inibição do crescimento das bactérias com os medicamentos utilizados, apenas com o controle positivo.Conclusão: As formulações de hidróxido de cálcio e acetazolamida não apresentaram atividade inibitóriacontra o E. faecalis e C. albicans.

Introduction: The intracanal medication is essential for the treatment of avulsed tooth, being the calcium hydroxide paste usually indicated. The acetazolamide is an inhibiting substance of carbonic anhydrase and the bone resorption, being suggested as intracanal medication in avulsed teeth. However, for this substance became an alternative as intracanal therapeutic agent, it must be tested in vitro and in vivo. Objective: To evaluate, in vitro, the antimicrobial action of calcium hydroxide paste and acetazolamide associated with different vehicles, against the Enterococcus faecalis and Candida albicans. Materials and methods: The experimental groups were: acetazolamide (powder) with physiological serum; acetazolamide (powder) with glycerin; acetazolamide and calcium hydroxide (powder) in equal portions with physiological serum; acetazolamide and calcium hydroxide (powder) in equal portions added with glycerin; acetazolamide (liquid) and calcium hydroxide (powder) with physiological serum. Clorexidine was used for positive control in concentrations of 20%, 10%, 5%, 2.5%, 1.25% and 0.65% and glycerin was used as negative control. The study was carried through by test of diffusion in agar. Results: No experimental groups showed inhibition of the bacterial growth, only inhibited by the positive control. Conclusion: The groups with calcium hydroxide and acetazolamide did not show antimicrobial activity against the E. faecalis and C. albicans.

Effect of topical dorzolamide on rabbit central corneal thickness

Our objective was to study the effect of dorzolamide on corneal hydration in an 18-week controlled experiment using ultrasonic pachymetry. Twenty-eight male rabbits were divided randomly into four groups. The 7 rabbits in each group received eye drops containing either 2 percent (w/v) dorzolamide or placebo in their right eye, or in their left eye. The 2 percent dorzolamide rabbits were treated every 8 h. Fellow eyes are defined as eyes which did not receive either dorzolamide or placebo. The study was blind for both the person who applied the drug and the one who performed the pachymetry. The effect of treatments is reported on the basis of the percentage of pachymetric variation compared to the measurement made before drug application. There was no significant difference (P = 0.061) in pachymetric variation between dorzolamide (-4.42 ± 11.71 percent) and placebo (2.48 ± 9.63 percent). However, there was a significant difference (P = 0.0034) in pachymetric variation between the dorzolamide fellow eyes (-7.56 ± 10.50 percent) and the placebo (-4.42 ± 11.71 percent). In conclusion, dorzolamide did not increase the corneal thickness in rabbits.

Luminal acid in water-inmersion stress and the antiulcer effect of axetazolamide in the rat gastric mucosa

En ratas con píloro ligado, la secreción ácida gástrica (volumen y débito) de los animales en estrés por 10 h (inmovilización e inmersión en agua (21 grados celsius) fue significativamente menor que la de las ratas sin estrés. Acetazolomida, un potente inhibidor de la anhidrasa carbónica, administrada por vía intraperitoneal cada 5 h por un total de dos veces, dosis dependientemente (100, 50, 25 mg/kg) inhibió la secreción ácida y la formación de lesiones mucosas gástricas inducidas por el estrés (dosis antisecretoras). La acetazolamida (5 mg/kg) no tuvo efecto sobre dos parámetros (dosis noantisecretora). El incremento de las lesiones mucosas gástricas inducidas por la instilación intragástrica de 150 mM HCL (0.5 ml/h) durante el estrés, no fueinhibido por dosis antisecretoras de acetazolamida. Se concluye que: (1) la exposición de ratas por 10 h de estrés (inmovilización e inmersión en agua) disminuye la secreción ácida gástrica (2) la acetazolamida, inhibiendo la secreción ácida gástrica protégé a la mucosa de las lesiones inducidas por el estrés y (3) una mínima cantidad de ácido en el lumen gástrico es suficiente para desarrollar las lesiones inducidas por este tipo de estrés.

Efeito da dorzolamida em glaucoma crônico simples / Dorzolamide in crhronic glaucoma

Foram avaliados os resultados do uso de dorzolamida 2 por cento tópica, um inibidor da andrase carbônica, sobre a pressäo ocular, acuidade visual corrigida e perimetria visual, assim como seus efeitos colaterais em córnea, conjuntiva, câmara anterior, cristalino, fundo de olho e exames laboratoriais (hemograma, Na/K, plaquetas) e clínico geral em 22 olhos (11 pacientes portadores de glaucoma crônico simples. Os resultados obtidos revelam uma diminuiçäo de 26,8 por cento da PO após 30 dias de uso de dorzolamida 2 por cento, a qual se mantém com 6 meses e 1 ano do uso da medicaçäo. Näo houve variaçäo significativa na acuidade visual média durante o tratamento. Houve piora do campo visual em 6 pacientes, sendo que em 3 desses a piora foi inespecífica. Efeitos colaterais oculares leves foram observados em 12 olhos, mas näo se mantiveram em consultas subsequentes. Näo houve alteraçäo laboratorial adversa em nenhum paciente

Efeitos da diclorfenamida sobre a concentraçäo de zinco no humor aquoso e no sangue de cäes / Dicholorphenamide effects on zinc concentration in dog's aqueous humor and blood

Os óligo-elementos, embora presentes em quantidades diminutas no organismo, säo de extrema importância para a vida. O zinco é o segundo óligo-elemento mais abundante do corpo humano, sendo essencial para o desenvolvimento normal dos seres vivos. É componente necessário e integrante da anidrase carbônica, que constitui uma metaloenzima que se encontra em várias formas de isoenzima no corp. Nos processos ciliares de olhos humanos, ela é quase inteiramente pura; mediante a sua inibiçäo, consegue-se, provadamente pela filtraçäo da parede capilar, reduzir a produçäo do humor aquosos e, consequentemente, da pressäo ocular. Entre os inibidores da anidrase carbônica está a diclorfenamida, sendo uma sulfonamida comercializada em nosso meio, somente para uso oral. Este trabalho visou testar o efeito da diclorfenamida sobre o zinco do humor aquoso e do sangue, supondo-se uma interferência do zinco no controle da pressäo ocular; para isto foram estudados, em dezenove cäes, trinta e oito olhos, sendo que para cada cäo, um olho foi controle do outro

Carotid body chemoreception: the importance of CO2-HCO3- and carbonic anhydrase. (review)

The current hypotheses of carotid body (CB) chemoreception regard the glomus cells as the initial site of stimulus transduction. The consensus is that the transduction of chemical stimulus is coupled with the release of transmitter(s) from the glomus cells, which in turn generates action potentials in the afferent nerve terminals. Carbonic anhydrase (CA) is present in the glomus cells of the CB. Inhibition of CA activity in the CB in situ reduces the carotid chemosensory responses to CO2 and to O2, suggesting a common mechanism of chemosensing for both stimuli. However, CA inhibitors also block the red blood cell enzyme. Thus, the CO2 hydration reaction does not come to completion within the transit time of the blood from the lung to the CB. A steady-state reaction is not reached until later and so the PCO2 and pH levels in arterial blood samples are not the same as those sensed by the CB. Experiments in vitro using cat CB perfused and superfused with cell-free solutions, which had been pre-equilibrated with respiratory gases, strongly support the proposition that the CA activity in CB cells is essential for the speed and amplitude of the initial response to CO2 and for its subsequent adaptation. The immediate response to hypoxia also is delayed, but the late steady-state was less dependent on CA activity. In the nominal absence of CO2-HCO3- from the perfusate, hypoxic chemoreception persisted and its magnitude is not affected by CA inhibition, except for a delay which may be due to the initial alkaline pH of the glomus cells. Recent experiments performed in isolated glomus cells and in the whole CB show that hypoxia does not modify significantly the intracellular pH. By its simple catalytic function, CA can speed up the approach of the CO2 hydration reaction to equilibrium. However, CA may also contribute in the steady-state to the regulation of pHi by providing a continuous supply of H+ and HCO3-. Furthermore, CA performs a facilitatory role in the physiological chemosensory responses to CO2 and O2 in the presence of extracellular CO2-HCO3-. This role is likely to be related to the ion exchanger function and then to pHi regulation in the chemoreceptor cells