Calcium hydroxide associated with a new vehicle: Psidium cattleianum leaf extracts. Tissue response evaluation

Abstract The aim of this study was to evaluate edemogenic activity and subcutaneous inflammatory reaction induced by Psidium cattleianum leaf extracts associated with Ca(OH)2. Thirty male Wistar rats, split equally into three groups [aqueous extract + Ca(OH)2; ethanolic extract + Ca(OH)2; and propylene glycol + Ca(OH)2], were assessed every 3 h or 6 h (five animals in each period). Under general anesthesia, 0.2 mL of 1% Evans blue per 100 g of body weight was injected into the penile vein and each combination to be evaluated was subcutaneously injected into the dorsal region 30 min thereafter. Edemogenic activity was analyzed by spectrophotometry (λ=630 nm). For inflammatory reaction analysis, 50 rats received four polyethylene tubes (three experimental groups) and an empty tube (control group). The assessments were made at 7, 15, 30, 60, and 90 days, followed by hematoxylin-eosin staining and by the assignment of scores for evaluation of tissue response intensity. Ethanolic extract + Ca(OH)2 yielded the largest edemogenic activity at 3 h. Intergroup differences at 6 h were not significant. The histological analysis showed progressive repair over time (p<0.05) and aqueous and ethanolic extracts produced similar responses to those of the control and Ca(OH)2 + propylene glycol groups. Psidium cattleianum leaf extracts used as Ca(OH)2 vehicles evoked similar tissue response when compared to Ca(OH)2 associated with propylene glycol.

Analysis of the reaction of subcutaneous tissues in rats and the antimicrobial activity of calcium hydroxide paste used in association with different substances

The aim of this study was to evaluate the subcutaneous tissue response in rats and the antimicrobial activity of intracanal calcium hydroxide dressings mixed with different substances against E. faecalis. Fifty four rats were divided into three experimental groups according to the vehicle in the calcium hydroxide treatment: 0.4% chlorohexidine in propylene glycol (PG),Casearia sylvestris Sw in PG and calcium hydroxide+PG (control group). The pastes were placed into polyethylene tubes and implanted into the subcutaneous tissue. After 7, 14 and 30 days, the samples were processed and histologically evaluated (hematoxylin and eosin). The tissue surface in contact with the material was analyzed, and the quantitative analysis determined the volume density occupied by the inflammatory infiltrate (giant cells, polymorphonuclear cells and mononuclear cells), fibroblasts, collagen fibers and blood vessels. For the antimicrobial analysis, 20 dentin blocks infected with E. faecalis were treated with calcium hydroxide pastes in different vehicles; 0.4% chlorhexidine in PG, PG, extract fromCasearia sylvestris Sw in PG and a positive control (infection and without medication) for 7 days. The efficiency of the pastes was evaluated by the live/dead technique and confocal microscopy. The results showed that 0.4% chlorhexidine induced a higher inflammatory response than the other groups. The Casearia sylvestris Sw extract showed satisfactory results in relation to the intensity of the inflammatory response. In the microbiological test, there were no statistical differences between the evaluated intracanal dressings and the percentage of bacterial viability was between 33 and 42%. The control group showed an 86% viability. Antimicrobial components such as chlorhexidine or Casearia sylvestris Sw did not improve the antimicrobial activity against E. faecalis in comparison to the calcium hydroxide+PG treatment. In addition, the incorporation of chlorhexidine in the calcium hydroxide paste promoted the highest inflammatory response.

Characterization of gliclazide-polyethylene glycol solid dispersion and its effect on dissolution / Caracterização de gliclazida polietileno-glicol dispersão sólida eo seu efeito sobre a dissolução

The present study was initiated with the objective of studying the in vitro dissolution behavior of gliclazide from its solid dispersion with polyethylene glycol 6000. In this work, a solid dispersion of gliclazide with polyethylene glycol was prepared by the fusion method. In vitro dissolution study of gliclazide, its physical mixture and solid dispersion were carried out to demonstrate the effect of PEG 6000. Analytical techniques of FT-IR spectroscopy, differential scanning calorimetry and X-ray diffractometry were used to characterize the drug in the physical mixtures and solid dispersions. The dissolution studies of solid dispersion and physical mixture showed greater improvement compared to that of the pure drug. The mechanisms for increased dissolution rate may include reduction of crystallite size, a solubilization effect of the carrier, absence of aggregation of drug crystallites, improved wettability and dispersbility of the drug from the dispersion, dissolution of the drug in the hydrophilic carrier or conversion of drug to an amorphous state. The FT-IR spectra suggested that there was no interaction between gliclazide and PEG 6000 when prepared as a solid dispersion. DSC and XRD study indicated that the drug was converted in the amorphous form.

O presente trabalho foi realizado com o objetivo de estudar o comportamento in vitro da dissolução da gliclazida a partir da sua dispersão sólida com polietileno glicol 6000. Neste trabalho, as dispersões sólidas de gliclazida com polietileno glicol foram preparadas pelo método de fusão. Os estudo de dissolução in vitro da gliclazida, na mistura física e nas dispersões sólidas foram realizados para demonstrar o efeito de PEG 6000. Técnicas analíticas como espectroscopia FT-IR, calorimetria diferencial de varredura e difração de raios-X foram empregadas para caracterizar o fármaco nas misturas físicas e nas dispersoes sólidas. Os estudos de dissolução demonstraram maior melhoria. Os mecanismos para aumentar a velocidade de dissolução podem incluir a redução do tamanho dos cristais, a solubilização do carreador, a ausência de agregação dos cristais do fármaco, a melhoria da molhabilidade e dispersibilidade do fármaco a partir da dispersão, a dissolução do fármaco no carreador hidrofílico ou conversão da forma cristalina do fármaco para estado amorfo. Os espectros de FT-IR sugeriram que não houve interação entre gliclazide PEG 6000 e na sua combinação. Os estudos de DSC e DRX indicaram que o fármaco foi convertido para a forma amorfa.

Minimum alveolar concentrations and hemodynamic effects of two different preparations of sevoflurane in pigs

BACKGROUND: Original sevoflurane (Sevo A) is made with water, while a generic sevoflurane (Sevocris) is produced with propylene glycol as a stabilizing additive. We investigated whether the original and generic sevoflurane preparations differed in terms of their minimum alveolar concentration (MAC) values and hemodynamic effects. METHODS: Sixteen pigs weighing 31.6±1.8 kg were randomly assigned to the Sevo A or Sevocris groups. After anesthesia induction via mask with the appropriate sevoflurane preparation (6 percent in 100 percent oxygen), the MAC was determined for each animal. Hemodynamic and oxygenation parameters were measured at 0.5 MAC, 1 MAC and 1.5 MAC. Histopathological analyses of lung parenchyma were performed. RESULTS: The MAC in the Sevo A group was 4.4±0.5 percent, and the MAC in the Sevocris group was 4.1±0.7 percent. Hemodynamic and metabolic parameters presented significant differences in a dose-dependent pattern as expected, but they did not differ between groups. Cardiac indices and arterial pressures decreased in both groups when the sevoflurane concentration increased from 0.5 to 1 and 1.5 MAC. The oxygen delivery index (DO2I) decreased significantly at 1.5 MAC. CONCLUSION: Propylene glycol as an additive for sevoflurane seems to be as safe as a water additive, at least in terms of hemodynamic and pulmonary effects.

Effects of triptolide on hypothalamic-pituitary-adrenal axis of rats / 法医学杂志

OBJECTIVE@#To observe the effects of triptolide on the hypothalamic-pituitary-adrenal axis (HPAA) of rats in light of morphological and functional changes.@*METHODS@#Thirty Sprague-Dawley (SD) male rats were randomized into 3 groups and given 2% propylene glycol, mixture of propylene glycol and prednisone acetate or compounds of propylene glycol and triptolide by gavage, respectively, for consecutive 7 weeks. Determination in the 3 groups was conducted concerning the contents of blood plasma cortisol (COR), adrenocorticotropic hormone (ACTH) and corticotropin-releasing hormone (CRH) besides measurement of the rats' body weight, coefficient of the adrenal gland and observation of the histopathological changes in fascicular zone of adrenal cortex. Immunohistochemical staining technique was used to detect the expression of ACTH in pituitary in the 3 groups.@*RESULTS@#(1) The content of COR in the groups of triptolide and prednisone acetate appeared lower and serum ACTH showed no significant difference, but CRH in the group of triptolide was augmented as compared with the control group (P < 0.05). (2) The rats' weight in the groups of triptolide and prednisone acetate was declined, and yet, the coefficient of the adrenal gland remained no significant change in comparison with the controls. HE staining and electron microscopy examination revealed thinned and constricted zona fasciculata in adrenal gland in the rats of triptolide and prednisone acetate, with hypofunction. ACTH expression in the group of triptolide was higher than that of the control group (P < 0.05).@*CONCLUSION@#Morphologically and functionally, the findings suggest that long-term use of triptolide may result in atrophied cortex and hypofunction of the adrenal gland, leading to augmented production and secretion of CRH and ACTH from respective hypothalamic and pituitary.

Interference of propylene glycol with the hole-board test

Experimental drugs and/or plant extracts are often dissolved in solvents, including propylene glycol. Nevertheless, there is evidence for psychoactive properties of this alcohol. In this study we found that in the hole-board test 10 percent propylene glycol did not modify the head-dipping behavior. However, 30 percent propylene glycol induced an increase in the number of head-dips (46.92 + or - 2.37 compared to 33.83 + or - 4.39, P<0.05, ANOVA/Student-Newman-Keuls), an effect comparable to that obtained with 0.5 mg/kg diazepam (from 33.83 + or - 4.39 to 54 + or - 3.8, P<0.01, ANOVA/Student-Newman-Keuls). These results demonstrate that 30 percent propylene glycol has significant anxiolytic effects in this model and therefore cannot be used as an innocuous solvent

Comportamento dos tecidos periodontais frente a perfuraçöes radiculares tratadas com hidróxido de cálcio, polímero HTR-40 e hidroxiapatita (Avaliaçäo histológica em dentes de cäo) / Behaviour of periodontal tissues of the root perforations treated with calcium hydroxide, HTR-40 polymer and hydroxiapatite (Histological evaluation in dog's teeth)

A autora realizou um estudo visando avaliar, histologicamente, o comportamento dos tecidos periodontais de dentes pré-molares de 8 cäes, frente a perfuraçöes radiculares preenchidas com a pasta de hidróxido de cálcio P.A. e propileno glicol, com o polímero H.T.R-40, com a pasta L & C e com a hidroxiapatita. Os dentes experimentais foram tratados endodonticamente, os canais obturados, e as perfuraçöes, num total de 8 em cada animal (duas por hemiarco), foram executadas com uma broca "spiral drill" 58-E da Maillefer, posicionada na face distal do terço cervical da raiz mesial, em direçäo à furca. As perfuraçöes de cada hemiarco foram preenchidas com um dos materiais mencionados e sobre estes foi adaptada uma lâmina de guta-percha, cimento de óxido de zinco e eugenol de presa rápida, verniz cavitário e, ao final, amálgama de prata...