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991.
Luís Roque Noélia Duarte Maria Rosário Bronze Catarina Garcia Julia Alopaeus Jesus Molpeceres 《Biofouling》2013,29(8):880-892
AbstractGlycyrrhiza glabra L. is considered an important source of bioactive compounds. This study aimed at the development of an efficient solution for the treatment of oral candidiasis. Several extracts of Glycyrrhiza glabra L. were prepared using different solvents and their potential in vitro antifungal activity was assessed. Ethanolic extracts showed the most promising results against C. albicans. This extract was incorporated into mucoadhesive nanoparticles (PLA, PLGA and alginate), which were further included in an oral gel, an oral film and a toothpaste, respectively. The results showed that nanoparticles were successfully produced, presenting a mean size among 100–900?nm with high encapsulation efficiency. In vitro studies showed that the most bioadhesive formulation was the oral film with extract-loaded PLGA nanoparticles, followed by the toothpaste with extract-loaded alginate nanoparticles and the oral gel with extract-loaded PLA nanoparticles. 相似文献
992.
Cell-free extracts ofAnacystis nidulans were fractionated by discontinuous sucrose density gradient centrifugation resulting in the separation of two distinct types of membranes, the heavier one containing the chlorophyll and the lighter one devoid of chlorophyll. Identity of the latter with plasma membrane was confirmed by labeling of intact cells with impermeant marker,35S-diazobenzenesulfonate, prior to cell disruption. Both membrane fractions were purified individually by repeated recentrifugation on identical gradients. Purified membranes were subjected to dissociating polyacrylamide gel electrophoresis, either type of membranes yielding a distinct polypeptide pattern. After transfer of the polypeptides to nitrocellulose by Western blotting, two of the proteins, with molecular weights of approximately 55,000 and 32,000, respectively, gave strong and specifically complementary cross-reactions with antibodies raised against subunits I and II of the aa3-type cytochrome oxidase fromParacoccus denitrificans. The findings will be discussed in terms of the presence of aa3-type cytochrome oxidase in both plasma and thylakoid membranes ofAnacystis nidulans. 相似文献
993.
Matrix metalloproteinases (MMPs) are essential contributors to a microenvironment that promotes tumour progression. During the two last decades, inhibition of MMPs has become the focus of considerable interest for cancer therapy, and numerous synthetic metalloproteinase inhibitors have been developed by the pharmaceutical industry. However, clinical trials have shown disappointing efficacy or unexpected toxicity and new targets are thus eagerly awaited. The identification of endocytic clearance of several MMPs by the low-density lipoprotein receptor-related protein (LRP) might provide insight into novel strategies for controlling MMP level during malignant processes. This review attempts to summarize recent aspects on the cellular and molecular basis of LRP-mediated endocytic disposal of MMPs. 相似文献
994.
Thireau J Poisson D Zhang BL Gillet L Le Pécheur M Andres C London J Babuty D 《Free radical biology & medicine》2008,45(4):396-403
Cu/Zn superoxide dismutase (SOD1) is implicated in various pathological conditions including Down's syndrome, neurodegenerative diseases, and afflictions of the autonomic nervous system (ANS). To assess the SOD1 contribution to ANS dysfunction, especially its influence on cardiac regulation, we studied the heart rate variability (HRV) and cardiac arrhythmias in conscious 12-month-old male and female transgenic mice for the human SOD1 gene (TghSOD1). TghSOD1 mice presented heart rate reduction as compared with control FVB/N individuals. All HRV parameters reflecting parasympathetic activity were increased in TghSOD1. Pharmacological studies confirmed that the parasympathetic tone was exacerbated and the sympathetic pathway was functional in TghSOD1 mice. A high frequency of atrioventricular block and premature ventricular contractions was observed in TghSOD1. By biochemical assays we found that SOD1 activities were multiplied by 9 and 4 respectively in the heart and brainstem of transgenic mice. A twofold decrease in cholinesterase activity was observed in the heart but not in the brainstem. We demonstrate that SOD1 overexpression induces an ANS dysfunction by an exacerbated vagal tone that may be related to impaired cardiac activity of the cholinesterases and may explain the high occurrence of arrhythmias. 相似文献
995.
Saltijeral A Isla LP Pérez-Rodríguez O Rueda S Fernandez-Golfin C Almeria C Rodrigo JL Gorissen W Rementeria J Marcos-Alberca P Macaya C Zamorano J 《Obesity (Silver Spring, Md.)》2011,19(11):2268-2273
Obesity is considered as a strong risk factor for cardiovascular morbidity and mortality. 3D-wall motion tracking echocardiography (3D-WMT) provides information regarding different parameters of left ventricular (LV) myocardial deformation. Our aim was to assess the presence of early myocardial deformation abnormalities in nonselected obese children free from other cardiovascular risk factors. Thirty consecutive nonselected obese children and 42 healthy volunteer children were enrolled. None of them had any cardiovascular risk factor. Every subject underwent a 2D-echo examination and a 3D-WMT study. Mean age was 13.9 ± 2.56 and 13.25 ± 2.68 years in the nonobese and obese groups, respectively (59.7% and 40.3% male). Statistically significant differences were found for: interventricular septum thickness, LV posterior wall thickness, LV end-diastolic volume, LV end-systolic volume, left atrium volume, LV mass, and lateral annulus peak velocity. Regarding the results obtained by 3D-WMT assessment, all the evaluated parameters were statistically significantly different between the two groups. When the influence of obesity on the different echocardiographic variables was evaluated by means of multivariate logistic regression analysis, the strongest relationship with obesity was found for LV average circumferential strain (β-coefficient: 0.74; r(2): 0.55; P: 0.003). Thus, obesity cardiomyopathy is associated not only with structural cardiac changes, but also with myocardial deformation changes. Furthermore, this association occurs as early as in the childhood and it is independent from any other cardiovascular risk factor. The most related parameter to obesity is LV circumferential strain. 相似文献
996.
Background. In view of the functional capacity of glutathione synthesis in premature infants, and because the availability of cysteine is one the rate limiting steps in glutathione synthesis, we hypothesized that the low glutathione levels in premature infants may be due to immaturity of the active cellular uptake of cysteine.
Objective. To document in cells from newborn infants the effect of maturity and gender on cysteine uptake and consequently on glutathione levels.
Methods. Incorporation of L-[35S] cysteine was measured in leukocytes from cord blood and from tracheal aspirates (TAC) of newborn infants of varying (gestational as well as postnatal) ages and gender. Cysteine uptake was correlated with glutathione in TAC.
Results. The maturity of newborn girls positively influences cysteine uptake, which is responsible for 78% of the variation in their glutathione content. However, in newborn boys, gestational and postnatal ages did not influence the cysteine uptake.
Discussion. Cysteine uptake appears to be the limiting step explaining the reported gender-related differences in glutathione as well as the low levels of this central antioxidant found in premature infants. The immature cysteine uptake found in cells from premature infants raises questions about the bioavailability of this conditionally essential amino acid in regimens of parenteral nutrition for human neonates. 相似文献
Objective. To document in cells from newborn infants the effect of maturity and gender on cysteine uptake and consequently on glutathione levels.
Methods. Incorporation of L-[35S] cysteine was measured in leukocytes from cord blood and from tracheal aspirates (TAC) of newborn infants of varying (gestational as well as postnatal) ages and gender. Cysteine uptake was correlated with glutathione in TAC.
Results. The maturity of newborn girls positively influences cysteine uptake, which is responsible for 78% of the variation in their glutathione content. However, in newborn boys, gestational and postnatal ages did not influence the cysteine uptake.
Discussion. Cysteine uptake appears to be the limiting step explaining the reported gender-related differences in glutathione as well as the low levels of this central antioxidant found in premature infants. The immature cysteine uptake found in cells from premature infants raises questions about the bioavailability of this conditionally essential amino acid in regimens of parenteral nutrition for human neonates. 相似文献
997.
García-Palencia P Sánchez MA Nieto A Vilar MP González M Veiga-Lopez A González-Bulnes A Flores JM 《Animal reproduction science》2007,97(1-2):25-35
The objective of this study was to investigate differences in the expression of estrogen receptor-alpha (ERalpha), progesterone receptor (PR) and the proliferative indexes (Ki-67), in the uterus and oviduct of sheep with estrus synchronized either by prostaglandin analogues (Group PA, n=27) or by treatment with progestagens (Group P, n=29) on days 4 and 7 (day 0=estrus), when the embryos were collected. Immunohistochemical methods were used to quantify ERalpha, PR and Ki-67 in six superficial and deep compartments in the uterus and oviduct. The expression of ERalpha was significantly (P<0.01) lower in progestagen treated ewes than in prostaglandin analogues treated group in the luminal epithelium, superficial glands and superficial stroma in the uterus on day 4. The expression of PR was significantly lower in progesterone treated ewes than in the PA Group in the superficial gland (P<0.05) in both days studied. The lowest expression of PR was observed in the luminal caruncular epithelium and superficial glands in both treatments, obtaining the lowest levels on day 4 (P<0.05). There were significant differences between days 4 and 7 in the Ki-67 immunostaining in the luminal epithelium (P<0.01) and superficial glands (P<0.05). A higher cell proliferation was observed in the uterine epithelium (P<0.05) on day 4 in the animals treated with progestagens. Results indicate that sheep with synchronization of estrus with progestagens showed a reduction of ERalpha and PR protein expression in most of oviductal and uterine cells. 相似文献
998.
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1000.
Grégory Lacraz Florence Figeac Jamileh Movassat Nadim Kassis Josiane Coulaud Anne Galinier Corinne Leloup Danielle Bailbé Fran?oise Homo-Delarche Bernard Portha 《PloS one》2009,4(8)