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Interesting Perspective (interesting + perspective)
Selected AbstractsDetermination of melatonin in wine and plant extracts by capillary electrochromatography with immobilized carboxylic multi-walled carbon nanotubes as stationary phaseELECTROPHORESIS, Issue 13 2010Patricia W. Stege Abstract The finding of melatonin, the often called "hormone of darkness" in plants opens an interesting perspective associated to the plethora of health benefits related to the moderate consumption of red wine. In this study, the implementation of a new method for the determination of melatonin in complex food matrices by CEC with immobilized carboxylic multi-walled carbon nanotubes as stationary phase is demonstrated. The results indicated high electrochromatographic resolution, good capillary efficiencies and improved sensitivity respect to those obtained with conventional capillaries. In addition, it was demonstrated highly reproducible results between runs, days and columns. The LOD for melatonin was 0.01,ng/mL. The method was successfully applied to the determination of melatonin in red and white wine, grape skin and plant extracts of Salvia officinalis L. [source] Life cycle assessment of a PPV plant applied to an existing SUW management systemINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 5 2003Francesco Di Maria Abstract The huge amount of wastes produced by modern and developed countries involves important aspects of economical, social and technical fields and also of the environment. For this reason, different technologies have been proposed for trying to reduce the impact of waste management and disposal. Generally waste management system consists of different steps like selective collection, recycling and reuse operation, energy recovery from waste and landfilling. A new technology proposed for thermal waste treatment is the plasma pyrolysis vetrification (PPV). This system seems to have interesting perspective due to the possibility of thermal treatment of dangerous slag or waste producing inactivate vetrified substances that can be landfilled or used as building materials with no impact on the environment. In this study, the effect of the application of a PPV plant on an existing waste management system was evaluated with a life cycle assessment (LCA) analysis. All the activities connected to the existing system have been carefully analysed by collecting a large quantity of experimental data. Some assumptions have been made, in particular, on the PPV plant performance. LCA analysis results illustrate how the environmental benefits arising from the adoption of the new technology, concerns only few aspects of the whole system. Copyright © 2003 John Wiley & Sons, Ltd. [source] The regulation of HIV-1 transcription: Molecular targets for chemotherapeutic interventionMEDICINAL RESEARCH REVIEWS, Issue 5 2006Miguel Stevens Abstract The regulation of transcription of the human immunodeficiency virus (HIV) is a complex event that requires the cooperative action of both viral and cellular components. In latently infected resting CD4+ T cells HIV-1 transcription seems to be repressed by deacetylation events mediated by histone deacetylases (HDACs). Upon reactivation of HIV-1 from latency, HDACs are displaced in response to the recruitment of histone acetyltransferases (HATs) by NF-,B or the viral transcriptional activator Tat and result in multiple acetylation events. Following chromatin remodeling of the viral promoter region, transcription is initiated and leads to the formation of the TAR element. The complex of Tat with p-TEFb then binds the loop structures of TAR RNA thereby positioning CDK9 to phosphorylate the cellular RNA polymerase II. The Tat-TAR-dependent phosphorylation of RNA polymerase II plays an important role in transcriptional elongation as well as in other post-transcriptional events. As such, targeting of Tat protein (and/or cellular cofactors) provide an interesting perspective for therapeutic intervention in the HIV replicative cycle and may afford lifetime control of the HIV infection. © 2006 Wiley Periodicals, Inc. Med Res Rev, 26, No. 5, 595,625, 2006 [source] Pathogens as potential selective agents in the wildMOLECULAR ECOLOGY, Issue 22 2009MÉLANIE DIONNE Pathogens are considered a serious threat to which wild populations must adapt, most particularly under conditions of rapid environmental change. One way host adaptation has been studied is through genetic population structure at the major histocompatibility complex (MHC), a complex of adaptive genes involved in pathogen resistance in vertebrates. However, while associations between specific pathogens and MHC alleles or diversity have been documented from laboratory studies, the interaction between hosts and pathogens in the wild is more complex. As such, identifying selective agents and understanding underlying co-evolutionary mechanisms remains a major challenge. In this issue of Molecular Ecology, Evans & Neff (2009) characterized spatial and temporal variation in the bacterial parasite community infecting Chinook salmon (Oncorhynchus tshawytscha) fry from five populations in British Columbia, Canada. They used a 16S rDNA sequencing-based approach to examine the prevalence of bacterial infection in kidney and looked for associations with MHC class I and II genetic variability. The authors found a high diversity of bacteria infecting fry, albeit at low prevalence. It was reasoned that spatial variability in infection rate and bacterial community phylogenetic similarity found across populations may represent differential pathogen-mediated selection pressures. The study revealed some evidence of heterozygote advantage at MHC class II, but not class I, and preliminary associations between specific MHC alleles and bacterial infections were uncovered. This research adds an interesting perspective to the debate on host,pathogen co-evolutionary mechanisms and emphasizes the importance of considering the complexity of pathogen communities in studies of host local adaptation. [source] Clinical presentation and management of antibody-induced failure of botulinum toxin therapyMOVEMENT DISORDERS, Issue S8 2004Dirk Dressler MD Abstract Therapy with botulinum toxin (BT) can fail due to numerous reasons, including failure due to formation of antibodies against BT (BT-AB, AB-TF). AB-TF is a secondary therapy failure, i.e. it occurs during the course of an ongoing BT therapy. It can be subjective or objective, temporary or permanent, and partial or complete. Complete AB-TF is usually preceded by injection series with partial AB-TF in which the therapeutic effect is reduced in its intensity and duration. AB-TF usually occurs within 2 or 3 years after initiation of BT therapy. After 4 years it is rare. BT-AB are neutralising or blocking by definition, i.e. they are directly interfering with BT's biological mechanism of action. Non-neutralizing or non-blocking antibodies occur. BT-AB can be detected by the mouse diaphragm assay, the mouse protection assay, and by patient-based tests such as the sternocleidomastoid test, the extensor digitorum brevis test, and the frowning test. Enzyme-linked immunosorbent assays (ELISA) have a low specificity and a low sensitivity for detection of BT-AB. BT-AB titres drop spontaneously after cessation of BT therapy but latencies are too long to be compatible with an effective BT therapy. BT dosage increase can be successful to overcome AB-TF when AB-TF is partial and when BT-AB titres are low. Usage of alternative BT type A preparations fail to overcome AB-TF. Alternative BT types, such as BT type B and BT type F, are initially successful in AB-TF, but stimulate formation of antibodies against the alternative BT types after few applications. BT-AB reduction with immunosuppressants and inactivation of BT-AB by intravenous immunoglobuline application has not yet been achieved. Extraction of BT-AB by plasmapheresis and immunoadsorption is possible but is associated with substantial logistic problems. Prevention of BT-AB formation, therefore, is of paramount importance. Identified risk factors for BT-AB formation must be taken into account when BT therapy is planned. The most interesting perspective seems to be the development of new BT preparations with reduced antigenicity. © 2004 Movement Disorder Society [source] Facial templates: a new perspective in three dimensionsORTHODONTICS & CRANIOFACIAL RESEARCH, Issue 1 2006CH Kau Structured Abstract Authors ,, Kau CH, Zhurov A, Richmond S, Cronin A, Savio C, Mallorie C Purpose ,, This paper describes the use of adult facial template in gender-specific facial analysis. Subjects and Methods ,, Eighty adults, mean age 24.5, were selected for the study. Laser-scanned images of the subjects were obtained under a reproducible and controlled environment with two Minolta Vivid 900 (Osaka, Japan) optical laser-scanning devices assembled as a stereo-pair. A set of left and right scanned images was taken for each subject and each scan took an average of 2.5 s. These scanned images were processed and merged to form a composite three-dimensional soft tissue reproduction of the subjects using commercially available reverse modelling software. The differences in facial morphology were measured using shell deviation colour maps. The facial template was used to compare differences between males vs. females groups and two subjects with facial disproportions. Results ,, The difference between the male and female facial templates was 1.28 ± 1.02 mm. The areas of greatest deviation were at the nasal, zygomatic area and lower jaw line. The results of the surface deviation maps between the templates and subjects with facial disproportion showed that the results could be applied for orthodontic diagnosis. Conclusions ,, The construction of the adult facial templates provides an interesting perspective into measuring changes in groups of patients and also acts as a useful template for the comparison of skeletal disproportion. [source] Contribution of neuroinflammation in burning mouth syndrome: indications from benzodiazepine useDERMATOLOGIC THERAPY, Issue 2008Fabrizio Guarneri ABSTRACT: Characterized by burning and painful oral sensations in absence of clinically significant mucosal abnormalities, the burning mouth syndrome is, despite numerous researches made, basically idiopathic and, consequently, difficult to treat effectively. Therapy with tricyclic antidepressants and benzodiazepines has been proposed, although the exact pathomechanism is not clear. The objective of this study is to define the possible reasons for the efficacy of benzodiazepines in the treatment of the burning mouth syndrome. Starting from the report of eight cases successfully treated with prazepam, the present authors examined the clinical features and the evidence from literature that support the possibility of a role of neuroinflammation in the pathogenesis of the burning mouth syndrome. Available data suggest that the nervous system could be crucial in the pathogenesis of the syndrome (altered perception of pain, disturbance of neural transmission, increased excitability, negative involvement of trigeminal-vascular system), and the present authors' experience lets them suppose a role for neuroinflammation. This hypothesis could also explain the positive response to benzodiazepines in some patients. The important role of neuroinflammation in dermatologic and oral diseases has been only recently investigated and acknowledged. Further studies on the connection between neuroinflammation and burning mouth syndrome could open interesting perspectives in the understanding and management of this difficult clinical condition. [source] Distinct, but compensatory roles of PAK1 and PAK3 in spine morphogenesisHIPPOCAMPUS, Issue 9 2008Bernadett Boda Abstract PAK1 and PAK3 belong to a family of protein kinases that are effectors of small Rho GTPases. In humans, mutations of PAK3 have been associated with mental retardation and result in in vitro studies in defects of spine morphogenesis. The functional specificities of PAK1 and PAK3 remain, however, unclear. Here, we investigated using loss and gain of function experiments how PAK1 and PAK3 affect spine morphology in hippocampal slice cultures. We find that while knockdown of PAK3 is associated with an increase in thin, elongated, immature-type spines, downregulation of PAK1 does not alter spine morphology. Conversely, expression of a constitutively active form of PAK3 remains without effect, while expression of constitutively active PAK1 results in the formation of spines with smaller head diameters. Interestingly, expression of constitutively active PAK1 can rescue the long spine phenotype induced by suppression of PAK3. We conclude that while PAK1 and PAK3 share distinct roles in the regulation of spine morphogenesis, their activity may overlap allowing the compensation of the PAK3 deficit by PAK1. This result opens interesting perspectives in the context of reversing the spine defects associated with PAK3 mutations. © 2008 Wiley-Liss, Inc. [source] Hibiscus polyphenol-rich extract induces apoptosis in human gastric carcinoma cells via p53 phosphorylation and p38 MAPK/FasL cascade pathwayMOLECULAR CARCINOGENESIS, Issue 2 2005Hui-Hsuan Lin Abstract In view of the continuing need for effective anticancer agents, and the association of diet with reduced cancer risk, edible plants are increasingly being considered as sources of anticancer drugs. Hibiscus sabdariffa Linne (Malvaceae), an attractive plant believed to be native to Africa, is cultivated in the Sudan and Eastern Taiwan. Polyphenols had been demonstrated previously to possess antioxidative and antitumor promoting effects. In this study, investigations were conducted to examine the mechanism of the anticancer activity of H. sabdariffa L., Hibiscus polyphenol-rich extracts (HPE). Using HPLC assay, HPE was demonstrated to contain various polyphenols. HPE induced cell death of eight kinds of cell lines in a concentration-dependent manner. Among them human gastric carcinoma (AGS) cells were the most susceptible to HPE (0.95 mg/mL HPE inhibited its growth by 50%). Our results revealed that AGS cells underwent DNA fragmentation, and had an increase in the distribution of hypodiploid phase (apoptotic peak, 52.36%) after a 24-h treatment with HPE (2.0 mg/mL). This effect of HPE in AGS cells might be mediated via p53 signaling and p38 MAPK/FasL cascade pathway, as demonstrated by an increase in the phosphorylation of p53 and the usage of a specific p38 inhibitor, SB203580. Thus, our data present the first evidence of HPE as an apoptosis inducer in AGS cells and these findings may open interesting perspectives to the strategy in human gastric cancer treatment. © 2005 Wiley-Liss, Inc. [source] Synthesis, characterization, in vitro degradation and cytotoxicity of polyphosphazenes containing N -ethoxypyrrolidone side groupsPOLYMER INTERNATIONAL, Issue 2 2010Yunmei Bi Abstract A new biodegradable polyphosphazene (PYRMP) containing N -ethoxypyrrolidone and methoxyethoxyethoxy side groups was synthesized via a route of macromolecular substitution. The synthetic method of poly{bis[2-(2-oxo-1-pyrrolidinyl)ethoxy]phosphazene} (PYRP) was improved. The thermal properties of the polymers were investigated using differential scanning calorimetry. Degradation studies were carried out in vitro with varying pH conditions. The in vitro cytotoxicity of PYRMP and its hydrolysis products was evaluated using the methyl tetrazolium (MTT) cytotoxicity test in HepG2 cell culture. PYRMP and PYRP have low glass transition temperatures of ,68.8 and ,59.6 °C, respectively. The polymers show a higher degradation rate at pH = 5.0 than at both pH = 7.4 and 8.0. The degradation process of PYRMP in different buffer solutions is discussed. The MTT test reveals that PYRMP at concentrations below 800 µg mL,1 and its hydrolysis products are non-toxic to HepG2 cells. Moreover, the hydrolysis products diluted 10 times are able to promote cell proliferation. This study shows that polyphosphazene containing N -ethoxypyrrolidone subsituents provides interesting perspectives for various biomedical applications. Copyright © 2009 Society of Chemical Industry [source] Sodium butyrate induces P53-independent, Fas-mediated apoptosis in MCF-7 human breast cancer cellsBRITISH JOURNAL OF PHARMACOLOGY, Issue 1 2002Valérie Chopin This study was performed to determine the effect and action mechanisms of sodium butyrate (NaB) on the growth of breast cancer cells. Butyrate inhibited the growth of all breast cancer cell lines analysed. It induced cell cycle arrest in G1 and apoptosis in MCF-7, MCF-7ras, T47-D, and BT-20 cells, as well as arrest in G2/M in MDA-MB-231 cells. Transient transfection of MCF-7 and T47-D cells with wild-type and antisense p53 did not modify butyrate-induced apoptosis. Pifithrin-,, which inhibits the transcriptional activity of P53, did not modify cell growth or apoptosis of MCF-7 and T47-D cells treated with butyrate. These results indicate that P53 was not involved in butyrate-induced growth inhibition of breast cancer cells. Treatment of MCF-7 cells with anti-Fas agonist antibody induced cell death, indicating that Fas was functional in these cells. Moreover, butyrate potentiated Fas-induced apoptosis, as massive apoptosis was observed rapidly when MCF-7 cells were treated with butyrate and anti-Fas agonist antibody. In addition, butyrate-induced apoptosis in MCF-7 cells was considerably reduced by anti-Fas antagonist antibody. Western blot analysis showed that butyrate increased Fas and Fas ligand levels (Fas L), indicating that butyrate-induced apoptosis may be mediated by Fas signalling. These results demonstrate that butyrate inhibited the growth of breast cancer cells in a P53-independent manner. Moreover, it induced apoptosis via the Fas/Fas L system and potentiated Fas-triggered apoptosis in MCF-7 cells. These findings may open interesting perspectives in human breast cancer treatment strategy. British Journal of Pharmacology (2002) 135, 79,86; doi:10.1038/sj.bjp.0704456 [source] | |||||||||||||