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2.
Background: The onset of menopause marks a pivotal time in which the incidence of hypertension and of cardiovascular disease (CVD) begins to increase dramatically in women. Before menopause, the incidences of these diseases are significantly lower in women than in age-matched men. After menopause, the rates of these diseases in women eventually approximate those in men. The loss of endogenous estrogen at menopause has been traditionally believed to be the primary factor involved in these changes. Objective: This review summarizes recent findings regarding the effectiveness of botanicals in the treatment of some menopausal symptoms and other symptoms of aging (eg, rise in arterial pressure, cognitive decline, insulin resistance, and hyperlipidemia). Methods: Articles were selected for inclusion in this review based on the significance of the research and contribution to the current understanding of how each botanical elicits cardioprotective effects. To this end, PubMed and MEDLINE databases were searched, using terms that included the name of the specific botanical along with the relevant aspects of its action(s), such as blood pressure, glycemic control, and lipids. Most of the articles used were published within the past 5 years, although some older articles that were seminal in advancing the current understanding of botanicals were also included. Results: Soy has been found to lower plasma lipid concentrations and arterial pressure in postmenopausal women and age-matched men, and to have protective effects in heart disease and atherosclerosis of the carotid and coronary circulation. Soy was also found to lower fasting insulin concentrations and glycosylated hemoglobin concentrations. Grape seed extract, another frequently used botanical, contains polyphenols that have been found to reduce arterial pressure and salt-sensitive hypertension in estrogendepleted animal models. Conclusion: Several botanical compounds have been found to have beneficial effects in the treatment of the symptoms of menopause and other symptoms of aging, including CVD, cognitive decline, and metabolic diseases. 相似文献
3.
Conventional tools for measuring dietary exposure have well recognized limitations. Measurement of food-derived metabolites
in biofluids provides an alternative approach and our aim was to develop an experimental protocol which ensures that extraneous
variability does not obscure metabolic signals from ingested foods. Healthy adults consumed a standardized meal in the evening
before each test day and collected pooled overnight urine. On each test day of three different studies, urine was collected
in the fasted state and at different time points after consumption of a standardized breakfast. Metabolite fingerprinting
of samples using Flow Infusion Electrospray-Ionization Mass Spectrometry followed by multivariate data analysis showed strong
discrimination between overnight, fasting and postprandial samples, in each study separately and when data from the three
studies were pooled. Such differences were robust and highly reproducible within individuals on separate occasions. Urine
volume was an efficient data normalization factor for metabolite fingerprinting data. Postprandial urines had a stable chemical
composition over a period of 2–4 h after eating a standardized breakfast, suggesting that there is a flexible time window
for urine collection. Fasting urine samples provided a stable baseline for universal comparisons with postprandial samples.
A dietary exposure biomarker discovery protocol was validated by demonstrating that top-ranked signals discriminating between
fasting and 2–4 h postprandial urine samples could be linked to metabolites abundant in some components of the standardized
breakfast. We conclude that the protocol developed will have value in the search for biomarker leads of dietary exposure. 相似文献
4.
We evaluated the application of gas chromatography-mass spectrometry metabolic fingerprinting to classify forward genetic mutants with similar phenotypes. Mutations affecting distinct metabolic or signaling pathways can result in common phenotypic traits that are used to identify mutants in genetic screens. Measurement of a broad range of metabolites provides information about the underlying processes affected in such mutants. Metabolite profiles of Arabidopsis (Arabidopsis thaliana) mutants defective in starch metabolism and uncharacterized mutants displaying a starch-excess phenotype were compared. Each genotype displayed a unique fingerprint. Statistical methods grouped the mutants robustly into distinct classes. Determining the genes mutated in three uncharacterized mutants confirmed that those clustering with known mutants were genuinely defective in starch metabolism. A mutant that clustered away from the known mutants was defective in the circadian clock and had a pleiotropic starch-excess phenotype. These results indicate that metabolic fingerprinting is a powerful tool that can rapidly classify forward genetic mutants and streamline the process of gene discovery. 相似文献
5.
1H NMR spectroscopy is one of the techniques whose potential is currently being explored in the emerging field of metabolomics. It is a non-targeted method, producing signals for all proton-containing chemical species. For crude plant materials the spectra are always complex, with many signals overlapping. Hence a most suitable approach for analysing them is 'metabolite fingerprinting', which is aimed at highlighting compositional similarities and exploring the overall natural variability in a population of samples. The most commonly used method for this is principal component analysis (PCA), as it allows the whole spectral trace to be analysed and the vast quantity of information to be simplified. In this paper we investigate whether there are factors which may affect the NMR spectra in a way that subsequently decreases the robustness of the metabolite fingerprinting by PCA. Imperfections in the signal registration (i.e. inconsistency of the peak position) are generally detrimental to analysing whole traces by multivariate methods. The sources of such problems are illustrated through specially designed repeatability studies using potato and tomato samples, and the analysis of a tea dataset containing many samples. Careful sample preparation can help to limit peak shifts; for instance here by attempting to control the pH of the extracts. In addition, some compounds are susceptible to interactions affecting their chemical shifts and mathematical alignment of peaks may be necessary. Lastly factors such as resolution can also affect analyses and must be carefully adjusted. Our choice of examples aims to raise awareness of potential problems. We do not question the validity of the NMR approach, but point out those areas where special care may need to be taken. 相似文献
6.
Amino Acids - Impurities in nine dietary supplements containing l-tryptophan were evaluated using an HPLC methodology. In five tested products, the total impurities were higher than the thresholds... 相似文献
7.
Hydrated diacylglycerol-PEG lipid conjugates, glyceryl dioleate-PEG12 (GDO-PEG12) and glyceryl dipalmitate-PEG23 (GDP-PEG23), spontaneously form uni- or oligolamellar liposomes in their liquid crystalline phase, in distinct difference from the PEGylated phospholipids which form micelles. GDP-PEG23 exhibits peculiar hysteretic phase behavior and can arrange into a long-living hexagonal phase at ambient and physiological temperatures. Liposomes of GDO-PEG12 and its mixture with soy lecithin exchange lipids with the membranes much more actively than common lecithin liposomes; such an active lipid exchange might facilitate the discharging of the liposome cargo upon uptake and internalization, and can thus be important in drug delivery applications. Diacylglycerol-PEG lipid liposome formulations can encapsulate up to 20-30 wt.% lipophilic dietary supplements such as fish oil, coenzyme Q10, and vitamins D and E. The encapsulation is feasible by way of dry mixing, avoiding the use of organic solvent. 相似文献
8.
The production of food supplements containing cyanobacteria is a growing worldwide industry. While there have been several
reports of health benefits that can be gained from the consumption of these supplements, there have also been a growing number
of studies showing the presence of toxins some of which (for example microcystins) are known to affect human health. In this
paper, we report a multiplex polymerase chain reaction (PCR) technique that can be used to identify microcystin contamination
in dietary supplements produced for human consumption. This method involves a PCR reaction containing three primer pairs,
the first of which is used to amplify a 220-bp fragment of 16s rDNA specific to Microcystis, the most common microcystin-producing cyanobacterium. The second primer pair is used to amplify a 300-bp fragment of the
mcyA gene, linked to microcystin biosynthesis in Anabaena, Microcystis, and Planktothrix. A third primer pair, used as a positive control, results in the amplification of a 650-bp fragment from the phycocyanin
operon common to all cyanobacteria. This technique was found to be useful for detecting the presence of toxigenic Microcystis in all dietary supplements produced from the nontoxic cyanobacterium Aphanizomenon flos-aquae. 相似文献
9.
Celiac disease (CD) is a chronic intestinal disorder of public health concern caused by gluten ingestion in sensitive individuals. Gluten is a protein found not only in gluten-containing food but also as normal component of drugs and dietary supplements. Detection of gluten in dietary supplements is a very important task required for establishing their gluten status, which is highly important for the safety of products consumed by CD and gluten-sensitive patients. In this paper, we investigated the presence of gluten in twenty one common dietary supplements from the national market using the immunochromatographic assay. This visual assay proved to be an efficient rapid tool for gluten screening as an alternative to the ELISA techniques. The results have shown the presence of gluten in 23.8% of the investigated samples (vitamins, minerals, plant extracts, probiotics supplements, lactoferrin, propolis supplements). The results provide information which may contribute to the completion of the existing lists of gluten-free pharmaceuticals. It is known that for CD patients obtaining accurate information about the gluten content of a particular item is a difficult and time-consuming process. 相似文献
10.
Clade versus grade is an old question in taxonomy, going back as far as Darwin himself. Taxonomists have long believed that both must be taken into account in the formation of a general-purpose system. Recently clade has been elevated to a position of total dominance by a group of taxonomists who take their inspiration from Willi Hennig. Mayr has dubbed this approach cladism, and its exponents cladists. Cladistic theory is being vigorously developed and propounded by Hennig’s disputatious disciples, and much of the present-day theory would scarcely be recognized by the founder. I here address myself to what I consider the core features of present-day cladism. The essential distinctive feature of cladism, and its fatal flaw, is that a group is considered to be monophyletic, and thus taxonomically acceptable, only if it includes all the descendants from the most recent common ancestor. The traditional taxonomic view has been that a group can still be considered monophyletic (and thus taxonomically acceptable) after some of its more divergent branches have been trimmed off. This simple and seemingly innocuous difference has profound consequences to the taxonomic system. In Hennigian classification, organisms are ranked entirely on the basis of recency of common descent, that is, on the basis of the sequence of dichotomies in the inferred phylogeny. The amount of divergence scarcely enters into the picture. This procedure represents an effort to capture taxonomy for a narrowly limited special purpose, at the expense of the important and necessary function of providing a general-purpose system that can be used by all who are concerned with similarities and differences among organisms. The first corollary of the Hennigian concept of phylogenetic taxonomy is that no existing taxon can be ancestral to any other existing taxon. The descendant must be included in the same taxon as its ancestor. At the level of species this is palpably false. The ancestral species often continues to exist for an indefinite time after giving rise to one or more descendants. At the higher taxonomic levels adherence to the principle often requires excessive lumping or excessive splitting to avoid paraphyletic groups (i.e., groups that do not include all of their own descendants), and it forbids the taxonomic recognition of many conceptually useful groups. Neither the prokaryotes nor the dicotyledons form a cladistically acceptable taxon, since both are paraphyletic. The prokaryotes are putatively ancestral to the eukaryotes, and the dicotyledons are putatively ancestral to the monocotyledons. Many other traditional and readily recognizable taxa would have to be abandoned, without being replaced by conceptually useful groups. Fossils present a special problem, because the whole concept of cladistic classification depends on the absence of taxa at the branch points of the cladogram. Presumably all of these branch points were at some time in the past represented by actual taxa, which under cladistic theory can neither be assigned to one of their descendants nor treated as paraphyletic taxa. The difficulty is mitigated somewhat by the gaps in the known fossil record. Once it is admitted that paraphyletic as well as holophyletic groups are taxonomically acceptable, there is much value in cladistic methodology. Formal outgroup comparison for the establisment of polarity, and the emphasis on synapomorphies in the construction of a cladogram can both be usefully incorporated into taxonomic theory and practice. These require no revolution in taxonomic thought. There are unresolved problems, however, in how to gather and manipulate the data, and how to interpret the cladogram produced by computers. In any complex group, the computer may produce several or many cladograms of equal or nearly equal parsimony. This is particularly true in angiosperms, among which the extensive evolutionary parallelism casts doubt on the importance of parsimony and may lead to the production of hundreds of such cladograms for a single group. Despite the claims of objectivity and repeatability in cladistic taxonomy, the necessity for some subjective decisions remains. The Wagner groundplan-divergence method has most of the advantages of formal cladism without the most important disadvantages. Wagner accepts paraphyletic taxa in principle, and he casts a wider net for data bearing on the polarity of characters. In complex groups consisting of many taxa, however, both methods retain a strong subjective component in the computer manipulation and in the degree of reliance on absolute parsimony. 相似文献
11.
Chemical allergy is a common and important occupational health issue. Allergic sensitization induced by chemicals may take a variety of forms, including allergic contact dermatitis (skin sensitization) and allergic asthma and rhinitis (sensitization of the respiratory tract). There is a need to identify and characterize chemicals that have the potential to cause such sensitization reactions. Although a number of methods are available for the prospective analysis of skin sensitizing activity, there are currently no widely accepted tests for the identification of chemical respiratory allergens. We here describe a novel approach, cytokine fingerprinting, that has the potential to distinguish between chemical contact and respiratory allergens. The pattern of cytokine production by draining lymph node cells (LNCs) is evaluated following repeated topical exposure of mice to test chemicals. Experience to date reveals that contact allergens stimulate the selective development of type 1 immune responses associated with the secretion by draining LNCs of interferon gamma (IFN-gamma), but little interleukin-4 (IL-4) or interleukin-10 (IL-10). In contrast, chemical respiratory allergens are found to induce the appearance of preferential type 2 immune responses characterized by IL-4 and IL-10 production, but comparatively low levels of IFN-gamma. It is proposed that cytokine fingerprinting may permit the simultaneous identification and characterization of those chemicals that have the potential to cause allergic sensitization. 相似文献
12.
Type 2 diabetes, which accounts for the vast majority of diabetes worldwide is the result of a lowered sensitivity of the insulin receptors, resulting in impaired sugar metabolism is and chronic hyperglycaemia. There is no cure for type 2 diabetes, though some people with pre-diabetes and diabetes manage to reach and hold normal blood sugar levels, thus avoiding most of the complications that come with chronic hyperglycaemia; this is sometimes referred to as ‘reversing diabetes’. A healthy diet, with sufficient amounts of fruits, nuts, and vegetables is positively correlated with maintaining glycaemic control and prevention of diabetes-related complications. Whereas many different dietary phytochemicals have been considered to play a role in the glycaemic control and in prevention of degenerative diseases, there is currently no consensus on a particular mode of action. In this review, a range of pre-clinical studies and intervention studies, including randomised double-blind, placebo controlled clinical studies, are considered that investigate the role of dietary compounds in the prevention of type 2 diabetes-related complications. Three generic mechanisms of action can be discerned: compounds that reduce sugar uptake, compounds that restore insulin function, and compounds that attenuate the effects of oxidative stress and chronic inflammation. Particularly the latter has received wide attention in the form of activation of the Nrf2-antioxidant response element signalling pathway by various polyphenolic or triterpenoid compounds. Although individual reports may present models with clear looking signalling cascades, an overall review shows that many biologically active compounds in the human diet are pan assay interference substances that alter several cell functions simultaneously, which makes them less attractive for drug development.
相似文献
14.
The freshwater microalga Haematococcus pluvialis exhibits a unique morphological response to environmental stress, accumulating carotenoid pigment during encystment. The complexity of characterizing the different cell stages and monitoring the pigment cell content during the life cycle of this microalga is one of the main problems reported when assessing astaxanthin accumulation and degradation. Therefore, with the aim of studying the potential encystment response in this microalga by means of flow cytometry (FCM), we induced oxidative stress in cultures of vegetative growing cells by treating them with paraquat, a known generator of superoxide anion radicals. Two flow cytometric approaches were successfully used to monitor the effect of oxidative stress on morphological changes and genesis of carotenoids in H. pluvialis: (1) a cytometric characterization of different cell types based on analysis of the fluorescence of chlorophyll a vs the fluorescence of astaxanthin, and (2) staining with the fluorochromes hydroethidium (HE) and dihydrorhodamine 123 (DHR), in order to measure the in vivo intracellular levels of reactive oxygen species (ROS). FCM data showed that astaxanthin accumulation during encystment hampers the production of ROS. Furthermore, the cell content of astaxanthin seems to be a good indicator of the extent to which H. pluvialis cells undergo oxidative stress, and also of how the cells defend themselves under stress conditions. 相似文献
15.
Producing a comprehensive overview of the chemical content of biologically-derived material is a major challenge. Apart from ensuring adequate metabolome coverage and issues of instrument dynamic range, mass resolution and sensitivity, there are major technical difficulties associated with data pre-processing and signal identification when attempting large scale, high-throughput experimentation. To address these factors direct infusion or flow infusion electrospray mass spectrometry has been finding utility as a high throughput metabolite fingerprinting tool. With little sample pre-treatment, no chromatography and instrument cycle times of less than 5 min it is feasible to analyse more than 1,000 samples per week. Data pre-processing is limited to aligning extracted mass spectra and mass-intensity matrices are generally ready in a working day for a month’s worth of data mining and hypothesis generation. ESI-MS fingerprinting has remained rather qualitative by nature and as such ion suppression does not generally compromise data information content as originally suggested when the methodology was first introduced. This review will describe how the quality of data has improved through use of nano-flow infusion and mass-windowing approaches, particularly when using high resolution instruments. The increasingly wider availability of robust high accurate mass instruments actually promotes ESI-MS from a merely fingerprinting tool to the ranks of metabolite profiling and combined with MS/MS capabilities of hybrid instruments improved structural information is available concurrently. We summarise current applications in a wide range of fields where ESI-MS fingerprinting has proved to be an excellent tool for “first pass” metabolome analysis of complex biological samples. The final part of the review describes a typical workflow with reference to recently published data to emphasise key aspects of overall experimental design. 相似文献
16.
A new parameter could be introduced to facilitate the optimization of media used for cultivation of stock cultures on agar slants. This parameter reduces the amount of data generated in optimization experiments to one single value (hs-value) for each medium composition. The hs-value (high and stable product formation) allows an assessment of any medium formulation with regard to reproducibility and product formation, demonstrated for the production process of the antibiotic gallidermin by Staphylococcus gallinarum TÜ 3928. © Rapid Science Ltd. 1998 相似文献
17.
A lipase substrate microarray was obtained by printing aliphatic C2-C12 monoesters of (5R)- and (5S)-3-(5,6-dihydroxyhexyloxy)benzaldehyde by reductive alkylation on amine-functionalized glass slides coated with bovine serum albumin and a short PEG linker. The microarray features 12 substrates and their 66 possible binary mixtures spotted in a 9 x 36 spot array. Lipase reactions are detected by chemoselective NaIO(4)-oxidation of the 1,2-diol hydrolysis product to form an aldehyde, which is then tagged with the red-fluorescent dye rhodamine B sulfohydrazide . Specific fingerprints are produced by active enzymes. These experiments provide the first example of lipase fingerprinting using microarrays. 相似文献
18.
The objective of process characterization is to demonstrate robustness of manufacturing processes by understanding the relationship between key operating parameters and final performance. Technical information from the characterization study is important for subsequent process validation, and this has become a regulatory expectation in recent years. Since performing the study at the manufacturing scale is not practically feasible, development of scale-down models that represent the performance of the commercial process is essential to achieve reliable process characterization. In this study, we describe a systematic approach to develop a bioreactor scale-down model and to characterize a cell culture process for recombinant protein production in CHO cells. First, a scale-down model using 2-L bioreactors was developed on the basis of the 2000-L commercial scale process. Profiles of cell growth, productivity, product quality, culture environments (pH, DO, pCO2), and level of metabolites (glucose, glutamine, lactate, ammonia) were compared between the two scales to qualify the scale-down model. The key operating parameters were then characterized in single-parameter ranging studies and an interaction study using this scale-down model. Appropriate operation ranges and acceptance criteria for certain key parameters were determined to ensure the success of process validation and the process performance consistency. The process worst-case condition was also identified through the interaction study. 相似文献
20.
AbstractWe present a simplified paraffin embedding method suitable for unsuberized or unlignified small botanical samples (diameter < 0.3 cm). Only 2 h are required to yield plant tissues embedded in paraffin for anatomical observation and molecular analysis. Our method achieved morphological preservation of cell structures and conservation of nucleic acids that were equivalent to the traditional protocol. Fourier transform infrared spectrometry showed that the degree of degradation of the cytoplasmic components (e.g., protein) resulting from our simplified protocol was similar to that of the traditional protocol. The DNA samples embedded using the simplified method was extractable and could be used for PCR analysis. The DNA quality was equivalent to that embedded using the traditional method. 相似文献
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