About: Calyx is a(n) research topic. Over the lifetime, 1440 publication(s) have been published within this topic receiving 18418 citation(s).
01 May 2005-Phytotherapy Research
TL;DR: Hibiscus sabdariffa L. (English: roselle, red sorrel; Arabic: karkade), the calyces of which are used in many parts of the world to make cold and hot drinks, contains ascorbic acid (vitamin C).
Abstract: This article reviews the reported phytochemical, pharmacological and toxicological properties of Hibiscus sabdariffa L. (English: roselle, red sorrel; Arabic: karkade), the calyces of which are used in many parts of the world to make cold and hot drinks. Nutritionally, these contain ascorbic acid (vitamin C). In folk medicine, the calyx extracts are used for the treatment of several complaints, including high blood pressure, liver diseases and fever. The pharmacological actions of the calyx extracts include strong in vitro and in vivo antioxidant activity. In rats and rabbits, the extract showed antihypercholesterolaemic, antinociceptive and antipyretic, but not antiinflammatory activities. In rat and man a strong antihypertensive action has been demonstrated. The effects of the calyx extracts on smooth muscles in vitro are variable, but they mostly inhibit the tone of the isolated muscles. In healthy men, consumption of H. sabdariffa has resulted in significant decreases in the urinary concentrations of creatinine, uric acid, citrate, tartrate, calcium, sodium, potassium and phosphate, but not oxalate. Oil extracted from the plant's seeds has been shown to have an inhibitory effect on some bacteria and fungi in vitro. The plant extracts are characterized by a very low degree of toxicity. The LD50 of H. sabdariffa calyx extract in rats was found to be above 5000 mg/kg. A single report has suggested that excessive doses for relatively long periods could have a deleterious effect on the testes of rats. In view of its reported nutritional and pharmacological properties and relative safety, H. sabdariffa and compounds isolated from it (for example, anthocyanins and Hibiscus protocatechuic acid) could be a source of therapeutically useful products.
01 May 1997-Journal of Neurobiology
TL;DR: Early larval HU application to P[GAL4] strains that label specific neuron types enabled us to identify the origins of the two major classes of interneurons in the olfactory system and suggested that differentiated RI are present at the larval stage already and may be retained through metamorphosis.
Abstract: Hydroxyurea (HU) treatment of early first instar larvae in Drosophila was previously shown to ablate a single dividing lateral neuroblast (LNb) in the brain. Early larval HU application to P[GAL4] strains that label specific neuron types enabled us to identify the origins of the two major classes of interneurons in the olfactory system. HU treatment resulted in the loss of antennal lobe local interneurons and of a subset of relay interneurons (RI), elements usually projecting to the calyx and the lateral protocerebrum (LPR). Other RI were resistant to HU and still projected to the LPR. However, they formed no collaterals in the calyx region (which was also ablated), suggesting that their survival does not depend on targets in the calyx. Hence, the ablated interneurons were derived from the LNb, whereas the HU-resistant elements originated from neuroblasts which begin to divide later in larval life. Developmental GAL4 expression patterns suggested that differentiated RI are present at the larval stage already and may be retained through metamorphosis.
01 May 1986-Journal of the American Chemical Society
Wulfila Gronenberg1•Institutions (1)
09 Jul 2001-The Journal of Comparative Neurology
TL;DR: The data suggest that the many parallel channels of intrinsic neurons may each process different aspects of sensory input information within the mushroom body's calyx, which is particularly large in social Hymenoptera.
Abstract: The mushroom bodies are regions in the insect brain involved in processing complex multimodal information. They are composed of many parallel sets of intrinsic neurons that receive input from and transfer output to extrinsic neurons that connect the mushroom bodies with the surrounding neuropils. Mushroom bodies are particularly large in social Hymenoptera and are thought to be involved in the control of conspicuous orientation, learning, and memory capabilities of these insects. The present account compares the organization of sensory input to the mushroom body's calyx in different Hymenoptera. Tracer and conventional neuronal staining procedures reveal the following anatomic characteristics: The calyx comprises three subdivisions, the lip, collar, and basal ring. The lip receives antennal lobe afferents, and these olfactory input neurons can terminate in two or more segregated zones within the lip. The collar receives visual afferents that are bilateral with equal representation of both eyes in each calyx. Visual inputs provide two to three layers of processes in the collar subdivision. The basal ring is subdivided into two modality-specific zones, one receiving visual, the other antennal lobe input. Some overlap of modality exists between calycal subdivisions and within the basal ring, and the degree of segregation of sensory input within the calyx is species-specific. The data suggest that the many parallel channels of intrinsic neurons may each process different aspects of sensory input information.
16 Jan 2006-Journal of Ethnopharmacology
TL;DR: The lines of evidence suggest that the aqueous extracts from the dried calyx of roselle possess both antioxidant effects against LDL oxidation and hypolipidemic effects in vivo, however, its mechanism(s) of action remains to be elucidated.
Abstract: The present study was designed to investigate the hypolipidemic effects and antioxidant effects of Hibiscus sabdariffa L. (roselle) with regard to protection of LDL oxidation in vivo and ex vivo in rats made hypercholesterolemic by continuous cholesterol feeding. Administering the dried calyx extracts of roselle at doses of 500 and 1,000 mg/kg together with continuous cholesterol feeding to hypercholesterolemic rats for 6 weeks significantly decreased serum cholesterol level by 22% and 26%, respectively (p<0.001); serum triglycerides level by 33% and 28%, respectively (p<0.05); serum LDL level by 22% and 32%, respectively (p<0.05). However, serum HDL level was not affected. LDL was extracted from plasma of the hypercholesterolemic rats and the effects of the dried calyx extracts of roselle on the oxidation of LDL in vivo and ex vivo were examined. Six-week treatment with 250, 500 and 1,000 mg/kg of the extracts significantly decreased thiobarbituric acid reactive substances (TBARs) formation (p<0.05) while the formation of conjugated dienes during the oxidation of LDL induced by CuSO(4) was reduced, but not significantly different. These lines of evidence suggest that the aqueous extracts from the dried calyx of roselle possess both antioxidant effects against LDL oxidation and hypolipidemic effects in vivo. However, its mechanism(s) of action remains to be elucidated.