Equal Concentrations Of Glucose Research Articles

Patterns of sweetness preference in red wine according to consumer characterisation

The preference for sweet taste in red wine was examined according to consumer categories of age, gender, drinking experience and personality type (Big-5 personality-test). A total of 114 subjects revealed their preferences for sweetness after tasting dry red wine spiked with equal concentrations of glucose and fructose at 2g/L, 4g/L, 8g/L, 16g/L and 32g/L, following an ascending forced choice paired comparison method (2-AFC).The overall preference for sweetness was shown within the range of 4.8 to 21.9g/L, with maximal liking at 8g/L. Three patterns of response to sweetness were observed (sweet dislikers, sweet likers and indifferent to sweet) according to the different categories of consumers. Differences (p>0.05) were not found in sweetness preference among the categories up to 16g/L sugar except for the trait extraversion at 8g/L, where low extraverts showed a higher proportion of responses preferring the sweeter sample. Most significant differences were found only under the highest tasted concentration (32g/L). Females and novices preferred sweeter samples (p<0.05) when compared with the response of males and experienced consumers, respectively.

The effect of tolbutamide on rat embryonic development in vitro.

Tolbutamide (TOLB) is a sulfonylurea used to treat non-insulin-dependent diabetes mellitus and is a suspected teratogen. However, it is not possible to discriminate between potential teratogenic effects of TOLB and malformations produced by either drug-induced hypoglycemia or the diabetic state itself. We examined the direct effect of TOLB on rat embryos cultured in a rodent whole embryo culture system. CD strain rat embryos were cultured for 48 h beginning on day 9 of gestation (plug day = day 0). Tolbutamide was added at various concentrations (90-3,600 microM). At the end of culture, viable embryos were examined for morphological score, number of somite pairs, crown-rump and head lengths, and DNA and protein content. Tolbutamide produced dose-related decreases in all endpoints at concentrations (2,250-3,600 microM) which are two to four times the human therapeutic concentration. Sera from TOLB-treated rats were adjusted to contain equal concentrations of glucose and insulin and then used for embryo culture. Serum from TOLB-treated rats had no observable effect on embryonic development. The mechanism for the embryotoxic effect of TOLB is unknown; however, the drug was previously demonstrated to alter activity of purified yeast glutathione reductase (GR). Because GR may be important for normal embryonic development, the effect of TOLB on this enzyme activity in cultured rat embryos was evaluated. Tolbutamide (2,700 microM) reduced embryonic GR activity by 35-57%. These results indicate that TOLB has a direct embryotoxic effect at levels 2 to 4 times the usual therapeutic serum concentrations on developing rodent embryos which may be mediated by GR inhibition.

Lectinlike interactions of Fusobacterium nucleatum with human neutrophils

Fusobacterium nucleatum expresses lectinlike adherence factors which mediate binding to a variety of human tissue cells. Adherence is selectively inhibited by galactose, lactose, and N-acetyl-D-galactosamine. In this study, adherence of F. nucleatum to human peripheral blood polymorphonuclear neutrophils (PMNs) was investigated. The results indicated that the fusobacteria adhered to live and metabolically inactivated or fixed PMNs. Adherence of F. nucleatum resulted in activation of PMNs as determined by PMN aggregation, membrane depolarization, increased intracellular free Ca2+, superoxide anion production, and lysozyme release. Transmission electron micrographs showed that F. nucleatum was phagocytized by the PMNs. Microbicidal assays indicated that greater than 98% of F. nucleatum organisms were killed by PMNs within 60 min. Adherence to and activation of PMNs by F. nucleatum were inhibited by N-acetyl-D-galactosamine or lactose greater than galactose, whereas equal concentrations of glucose, N-acetyl-D-glucosamine, mannose, and fucose had little or no effect on F. nucleatum-PMN interactions. Pretreatment of the fusobacteria with heat (80 degrees C, 20 min) or proteases inhibited adherence to and activation of PMNs, but superoxide production was also stimulated by heated bacteria. The results indicate that interaction of F. nucleatum with PMNs is lectinlike and is probably mediated by fusobacterial proteins which bind to other human tissue cells. Adherence of F. nucleatum to PMNs in the absence of serum opsonins, such as antibodies and complement, may play an important role in PMN recognition and killing of F. nucleatum in the gingival sulcus and in the subsequent release of PMN factors associated with tissue destruction.

THE FOLIAR AND FLORAL NECTARIES OF TURNERA ULMIFOLIA L.

The floral and foliar nectaries of Turnera ulmifolia are specialized and are representative of others found in the Turneraceae. The foliar and floral nectary systems must be treated independently. Foliar nectaries are organized into a definite structure (composed of a base, rim, secretory tissue, modified epidermis) and are supplied with vascular tissue composed of both xylem and phloem. Nectar from foliar nectaries contained equal concentrations of glucose, fructose, and sucrose. Floral nectaries are an integral part of the basal portion of each filament. The nectariferous tissue is not supplied with vascular tissue and secretion lasts only a few hours. Nectar from these staminal nectaries yielded a sucrose‐dominant nectar containing also fructose, glucose, an unknown, and a trace amount of melezitose. Observations of flowering confirmed the reported short duration of the individual flowers.

The Foliar and Floral Nectaries of Turneara ulmifolia L.

The floral and foliar nectaries of Turnera ulmifolia are specialized and are representative of others found in the Turneraceae. The foliar and floral nectary systems must be treated independently. Foliar nectaries are organized into a definite structure (composed of a base, rim, secretory tissue, modified epidermis) and are supplied with vascular tissue composed of both xylem and phloem. Nectar from foliar nectaries contained equal concentrations of glucose, fructose, and sucrose. Floral nectaries are an integral part of the basal portion of each filament. The nectariferous tissue is not supplied with vascular tissue and secretion lasts only a few hours. Nectar from these staminal nectaries yielded a sucrose-dominant nectar containing also fructose, glucose, an unknown, and a trace amount of melezitose. Observations of flowering confirmed the reported short duration of the individual flowers.