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At least 37 records · Page 2Linked to original sources
PubMed2004

[Effect of kidney-warming and astringent therapy on plasma endothelin and interleukin-2 receptor in patients with nephrotic syndrome].

OBJECTIVE: To explore the effect and mechanism of kidney-warming and astringent therapy in treating nephrotic syndrome patients with deficiency of spleen and kidney yang and overflow of water, and to observe the change of plasma endothelin and interleukin-2 receptor after treatment. METHODS: Forty-four patients were randomly divided into conventional steroid treated group (control group, 20 cases) and conventional steroid plus kidney-warming and astringent therapy treated group (treatment group, 24 cases). The levels of plasma endothelin (ET) and soluble interleukin-2 receptor (sIL-2) were observed. RESULTS: Before treatment, plasma ET and sIL-2 in the patients were significantly higher than those in healthy people (P<0.01). After treatment, the ET and sIL-2 levels were obviously improved in both treated groups (P<0.05) and the improvement in the treatment group was more obvious. The difference between the two treated groups after treatment was significant (P<0.05). CONCLUSION: Conventional treatment plus kidney-warming and astringent therapy can effectively improve the levels of plasma ET and sIL-2 in treating nephrotic syndrome patients with deficiency of spleen and kidney yang and overflow of water, and hence alleviate the damage of renal tissue.

Adrenal Cortex Hormones↗
PubMed1988

Natural astringency in foodstuffs--a molecular interpretation.

The structures of plant polyphenols (vegetable tannins) are briefly reviewed. Their interactions with proteins, polysaccharides, and the alkaloid caffeine are discussed at the molecular level, and these fundamental properties are related to the quality of astringency that polyphenols possess. The various ways in which astringency may be modified and ultimately lost are outlined in relation to the aging of red wines, the formation of nonbiological hazes in beers and lagers, and the ripening of fruit.

Astringents↗
PubMed1998

[Effects of an antidiarrhoeica containing an extract from geranium herb on astringent action and short-circuit current across jejunal mucosa].

A consists of berberine chloride and an extract from geranium herb. To clarify mechanisms of the antidiarrheal effect of Phelloberin-A, we investigated the astringent action by determining its binding activity to rabbit hemoglobin and effects on active transport, which was indicated by short-circuit current (Isc), in rat jejunum by the Ussing chamber technique. The effects of berberine chloride and geranium herb on both the binding activity to hemoglobin and the electrophysiological parameters such as Isc were compared with those of the antidiarrhoeicas, tannic acid, albumin tannate and bismuth subnitrate. Geranium herb, tannic acid and bismuth subnitrate increased significantly the binding activity to hemoglobin at concentrations of > 1 mg/ml, > 0.3 mg/ml and 10 mg/ml, respectively, but berberine or albumin tannate did not. Geranium herb and tannic acid dose-dependently and moderately increased Isc in rat jejunal mucosa and the increase became significant at a concentration of 10 mg/ml. Neither berberine chloride, albumin tannate nor bismuth subnitrate affected Isc. In contrast, cholera toxin, which increases the secretion from intestinal mucosa to the lumen and induces diarrhea, decreased Isc at a concentration of 0.1 mg/ml. The decrease of Isc induced by cholera toxin was antagonized by pretreatment with geranium herb (10 mg/ml), indicating that geranium herb inhibited the toxin-induced increase in secretion. These results suggest that geranium herb possesses an astringent action and moderately increases Isc across the intestinal mucosa. Therefore, the effects may support an antidiarrheal effect of both geranium herb and Phelloberin-A.

Animals↗
PubMed1997

Intake, digestion, and nitrogen utilization by sheep fed tropical legumes with contrasting tannin concentration and astringency.

We conducted an experiment to determine the effects of concentration and astringency of extractable and bound condensed tannins (CT) in tropical legumes on intake, digestibility, and nitrogen (N) utilization by sheep. The test legumes (Desmodium ovalifolium and Flemingia macrophylla) had similar concentrations of extractable CT (90 g/kg DM) but different concentrations of bound CT and astringency of tannins. Chopped, sun-dried forage of each legume was sprayed with either water (control) or polyethylene glycol (PEG, 35 g/kg of DM) to bind extractable CT and fed daily (26 g/kg BW) to eight sheep with ruminal and duodenal cannulas. The sheep also received starch-extracted cassava meal intraruminally (4 g/kg BW) as a constant source of readily fermentable carbohydrates. Intake of the two legumes was not different (P > .05), but it increased an average of 10% (P < .01) when extractable CT were reduced from 90 to 50 g/kg of DM with PEG. Ruminal and total tract digestibilities of OM, NDF, and ADF were greater (P < .01) with D. ovalifolium than with F. macrophylla and increased for both legumes with the addition of PEG. Greater (P < .01) N flow to the duodenum, N absorbed from the intestine, and fecal N were observed with F. macrophylla than with D. ovalifolium. Extraction of CT with PEG resulted in less (P < .05) ruminal escape protein and less (P < .01) fecal N with both legumes, but apparent postruminal N digestion was not affected. Changes in the concentration of extractable CT in tropical legumes can significantly affect forage intake, digestion, and N utilization by sheep.

Animals↗
PubMed2003

Skin protectant drug products for over-the-counter human use; astringent drug products; final monograph; direct final rule. Direct final rule.

The Food and Drug Administration (FDA) is amending the regulation that established conditions under which over-the-counter (OTC) skin protectant astringent drug products are generally recognized as safe and effective and not misbranded. This action revises some labeling for astringent drug products to be consistent with the final rule for OTC skin protectant drug products (68 FR 33362, June 4, 2003) and adds labeling for certain small packages (styptic pencils). This action is part of FDA's ongoing review of OTC drug products. Elsewhere in this issue of the Federal Register, FDA is publishing a companion proposed rule, under FDA's usual procedure for notice-and-comment rulemaking, to provide a procedural framework to finalize the rule in the event the agency receives any significant adverse comments and withdraws this direct final rule.

Aluminum Compounds↗
PubMed2004

[Set up of in vitro methods able to detect the safety of astringent liquids].

AIM: Most of dental operators agree about a gengival retraction impregnated cord in order to obtain an accurate and overwide dental impression. Hemostatic agents allow the formation of the primary coagulum that determines/causes the retraction of gum connective. Sometimes these astringent liquids cause local inflammation reaction as reported in literature. Aim of this work was the evaluation of the cytotoxic and inflammatory action of the most common astringent liquid on human gum primary cells by in vitro tests. METHODS: For this purpose primary cultures of normal human oral keratinocytes were established, following used either as monolayer or as reconstituted model. All dental preparations were dissolved in CEC medium, diluted to the designed concentrations and applied to the cultured cells. The cytotoxicity was determined by using MTT test, able to evaluate the succinate dehydrogenase activity and therefore the cell viability. Control cultures were treated with CED alone, whereas sodium dodecyl sulphate (SDS) was used as a positive control. Furthermore, the inflammatory response, determined by measuring TNF-alpha and IFN-gamma release, was evaluated on a reconstituted multilayer human oral epidermis model. RESULTS: All agents tested showed a dose-dependent increase in the cytotoxicity to normal human gingival keratinocytes over the dose range examined. In particular the results obtained suggest the higher toxicity of the Astringedent X compound. CONCLUSION: The results obtained from the present studies not only provide useful estimates of relative toxicities of these preparations to human oral mucose, but also can be useful as a standard for cytotoxic and inflammatory assessment of newly developed dental preparations to be topically applied to the oral mucosa. It is important to note, however, that the interpolation of these findings to in vivo conditions remains to be done.

Astringents↗
PubMed2004

New method for evaluating astringency in red wine.

Astringency is an important sensory attribute of red wine. It is usually estimated by tasting and is subject to a certain subjectivity. It can also be estimated by using the gelatin index. This procedure is not very reproducible because there are many gelatins on the market with a heterogeneous composition. Furthermore, the gelatin index determines procyanidin concentration by acid hydrolysis that gives only an approximate result. This paper proposes a new and reproducible method that determines astringency by using ovalbumin as the precipitation agent and tannic acid solutions as standards. Statistical analysis of the results indicates that this method is more reproducible (RSD = 5%) than the gelatin index (RSD = 12%) and correlates better with sensorial analysis.

Chemical Precipitation↗
PubMed2004

Identification of the astringent taste compounds in black tea infusions by combining instrumental analysis and human bioresponse.

Application of taste dilution analyses on freshly prepared black tea infusions revealed neither the high molecular weight thearubigen-like polyphenols nor the catechins and theaflavins, but a series of 14 flavon-3-ol glycosides as the main contributors to the astringent taste perceived upon black tea consumption. Among these glycosides, the apigenin-8-C-[alpha-l-rhamnopyranosyl-(1-->2)-O-beta-d-glucopyranoside] was identified for the first time in tea infusions. Depending on the structure, the flavon-3-ol glycosides were found to induce a velvety and mouth-coating sensation at very low threshold concentrations, which were far below those of catechins or theaflavins; for example, the threshold of 0.001 micromol/L found for quercetin-3-O-[alpha-l-rhamnopyranosyl-(1-->6)-O-beta-d-glucopyranoside] is 190000, or 16000 times below the threshold determined for epigallocatechin gallate or theaflavin, respectively. Moreover, structure/activity considerations revealed that, besides the type of flavon-3-ol aglycon, the type and the sequence of the individual monosaccharides in the glycosidic chain are key drivers for astringency perception of flavon-3-ol glycosides.

Biflavonoids↗
PubMed1996

Responses of primate taste cortex neurons to the astringent tastant tannic acid.

In order to advance knowledge of the neural control of feeding, we investigated the cortical representation of the taste of tannic acid, which produces the taste of astringency. It is a dietary component of biological importance particularly to arboreal primates. Recordings were made from 74 taste responsive neurons in the orbitofrontal cortex. Single neurons were found that were tuned to respond to 0.001 M tannic acid, and represented a subpopulation of neurons that was distinct from neurons responsive to the tastes of glucose (sweet), NaCl (salty), HCl (sour), quinine (bitter) and monosodium glutamate (umami). In addition, across the population of 74 neurons, tannic acid was as well represented as the tastes of NaCl, HCl quinine or monosodium glutamate. Multidimensional scaling analysis of the neuronal responses to the tastants indicates that tannic acid lies outside the boundaries of the four conventional taste qualities (sweet, sour, bitter and salty). Taken together these data indicate that the astringent taste of tannic acid should be considered as a taste quality, which receives a separate representation from sweet, salt, bitter and sour in the primate cortical taste areas.

Animals↗
PubMed1998

Effect of gelatin (a model for salivary PRP) on the sensory astringency of 5-O-caffeoylquinic acid and tannic acid.

The present work investigates differences (triangular tests) between the astringency of 5-O-caffeoylquinic acid (5-CQA) and that of 5-CQA + gelatin. As an overall reference similar tests are reported using tannic acid (which has been shown to elicit a strong response). Finally, a time-intensity study on aqueous solutions of tannic acid (TA), TA + gelatin and gelatin, reveals relevant temporal factors. Although, under the experimental conditions, the majority of comparisons revealed statistically significant differences, in the time-intensity study no significant differences were found between TA + gelatin and gelatin, either for the intensity or the total duration of the response. Moreover, for the fading of the response there was no difference between TA + gelatin and TA. The main temporal contribution to the difference is in the onset of the response and can be related to the spectral differences observed in the earlier studies. It will be argued that these results may represent an important step in our understanding of the mechanisms of astringency.

Chlorogenic Acid↗
PubMed2006

Techniques for universal evaluation of astringency of green tea infusion by the use of a taste sensor system.

A practical method for universal evaluation of the astringency of green tea infusion by a taste sensor system was established. The use of EGCg aqueous solution as a standard enabled analysis with high accuracy and reproducibility. The sensor output was converted into taste-intensity on the basis of Weber's and Weber-Fechner laws, which was named the "EIT(ast)" value ("EIT" and "ast" are abbreviations for "Estimated Intensity of Taste" and "astringency" respectively). It was clarified that green tea infusion is to be classified into eight grades on the EIT(ast) scale. Furthermore, the high correlation of the EIT(ast) value with the human gustatory sense and the high stability of the taste sensor were proved.

Biosensing Techniques↗
PubMed1994

Polyphenols, astringency and proline-rich proteins.

Recent, NMR and precipitation, studies of molecular recognition of proline-rich proteins and peptides by plant polyphenols are described and rationalized. The action of polysaccharides and caseins in the moderation of the astringent response, which is engendered by polyphenols present in foodstuffs and beverages, is described. The possible influence of plant cell wall glycoproteins on the process of lignification is discussed in the light of the observed affinity of phenolic substrates for prolyl residues in protein structures.

Amino Acid Sequence↗
PubMed1999

A sclerosant with astringent properties developed in China for oesophageal varices: comparison with ethanolamine oleate and polidocanol.

BACKGROUND: Xiao zhi ling (XZL), which consists of Chinese nutgalls and aluminium potassium sulphate, is used as a local injection for the treatment of internal haemorrhoids in China. It is also used for endoscopic sclerotherapy of oesophageal varices. To date, however, it has not been compared with other sclerosants with regard to its safety and efficacy. METHODS: In the present study, the effect on the endothelium and the haemolytic and thrombosing effects of XZL were compared with those of 5% ethanolamine oleate and 1% polidocanol, using an endothelial cell line and red blood cells taken from rats and the dorsal marginal ear vein of rabbits. In addition, XZL was injected into the area surrounding varices in rats and its efficacy was studied endoscopically and histologically. RESULTS: Xiao zhi ling reduced the size of varices in rats after causing severe damage in the injected region. Compared with the other two sclerosants, however, XZL had little effect on the endothelium and was the least haemolytic compound. Furthermore, XZL did not cause thrombosis in the injected vein of a rabbit. CONCLUSIONS: These results suggest that XZL is another type of sclerosant with astringent rather than detergent properties. This compound should be used to treat oesophageal varices by paravariceal injection in smaller doses than 5% ethanolamine oleate and 1% polidocanol.

Alum Compounds↗
PubMed1996

Specificity of glossopharyngeal nerve responses to astringent compounds in Xenopus.

Astringent compounds were applied to oral epithelium of the clawed toad, Xenopus laevis, and rapidly rising and highly sensitive responses could be recorded from the whole glossopharyngeal nerve, but not at all from the trigeminal nerve. The response to 10 mM tannic acid decreased progressively with repetitive application. These responses to tannic acid, however, recovered completely by treating with chemicals capable of forming strong hydrogen and hydrophobic bonds. These chemical bondings are generally recognized as a model for polyphenol (tannin)-protein interactions based on physico-chemical measurements in vitro. The high affinities of these chemicals for tannic acid may be effective in releasing both bonds in the interaction of tannic acid with the receptor molecules. Our results provide in vivo evidence for this model.

Animals↗