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Date fruit (Phoenix dactylifera L) contains many macronutrients, minerals, vitamins and antioxidants which has been related to beneficial health properties. The objective of this study was to evaluate the potential efficacy of date fruit extract (DFE) against Al-induced toxicity in rat model. Male albino rats were divided into four groups of 8 rats : A control group, did not receive any treatment, the DFE group received date water extract (DFE) (500 mg kg-1 b. w) orally per day, the Al group: rats were supplemented with aluminum chloride (AlCl3) added to the drinking water at a concentration of 53.5 mg/ l and the DFE-Al group, rats received DFE along with AlCl3. The experimental duration lasted for six weeks. The data obtained indicate that Al administration results in inducing hematological alterations decline in the concentration of hemoglobin (Hb), RBC, Hct%, PCV, MCH, MCV and MCHC accompanied by a significant increase in WBC counts. Significant elevations in the serum inflammatory markers as C-reactive protein (CRP), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α) and the nuclear transcription factor (NF-κB) were observed in AlCl3-treated rats. The results demonstrated, also, that Al promotes lipid peroxidation and decreases the level of antioxidants: superoxide dismutase (SOD) and catalase (CAT) activities and reduced glutathione (GSH) contents in serum. However, treatment of AlCl3 group with DFE resulted in significant amelioration in the mentioned parameters as compared with AlCl3 group. According to the results obtained in the present study, it could be concluded that date fruits have beneficial health properties through immunomodulatory, anti-inflammatory and antioxidant effects. [ABSTRACT FROM AUTHOR]

Date fruit (Phoenix dactylifera L) contains many macronutrients, minerals, vitamins and antioxidants which has been related to beneficial health properties. The objective of this study was to evaluate the potential efficacy of date fruit extract (DFE) against Al-induced toxicity in rat model. Male albino rats were divided into four groups of 8 rats : A control group, did not receive any treatment, the DFE group received date water extract (DFE) (500 mg kg-1 b. w) orally per day, the Al group: rats were supplemented with aluminum chloride (AlCl3) added to the drinking water at a concentration of 53.5 mg/ l and the DFE-Al group, rats received DFE along with AlCl3. The experimental duration lasted for six weeks. The data obtained indicate that Al administration results in inducing hematological alterations decline in the concentration of hemoglobin (Hb), RBC, Hct%, PCV, MCH, MCV and MCHC accompanied by a significant increase in WBC counts. Significant elevations in the serum inflammatory markers as C-reactive protein (CRP), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α) and the nuclear transcription factor (NF-κB) were observed in AlCl3-treated rats. The results demonstrated, also, that Al promotes lipid peroxidation and decreases the level of antioxidants: superoxide dismutase (SOD) and catalase (CAT) activities and reduced glutathione (GSH) contents in serum. However, treatment of AlCl3 group with DFE resulted in significant amelioration in the mentioned parameters as compared with AlCl3 group. According to the results obtained in the present study, it could be concluded that date fruits have beneficial health properties through immunomodulatory, anti-inflammatory and antioxidant effects. [ABSTRACT FROM AUTHOR]

The nest is a protein motif of three consecutive amino acid residues with dihedral angles 1,2-αR αL (RL nests) or 1,2-αL αR (LR nests). Many nests form a depression in which an anion or δ-negative acceptor atom is bound by hydrogen bonds from the main chain NH groups. We have determined the extent and nature of this bridging in a database of protein structures using a computer program written for the purpose. Acceptor anions are bound by a pair of bridging hydrogen bonds in 40% of RL nests and 20% of LR nests. Two thirds of the bridges are between the NH groups at Positions 1 and 3 of the motif (N1N3-bridging)-which confers a concavity to the nest; one third are of the N2N3 type-which does not. In bridged LR nests N2N3-bridging predominates (14% N1N3: 75% N2N3), whereas in bridged RL nests the reverse is true (69% N1N3: 25% N2N3). Most bridged nests occur within larger motifs: 45% in (hexapeptide) Schellman loops with an additional 4 → 0 hydrogen bond (N1N3), 11% in Schellman loops with an additional 5 → 1 hydrogen bond (N2N3), 12% in a composite structure including a type 1β-bulge loop and an asx- or ST- motif (N1N3)-remarkably homologous to the N1N3-bridged Schellman loop-and 3% in a composite structure including a type 2β-bulge loop and an asx-motif (N2N3). A third hydrogen bond is a previously unrecognized feature of Schellman loops as those lacking bridged nests have an additional 4 → 0 hydrogen bond., (© 2014 Wiley Periodicals, Inc.)

Helical parameters displayed on a Ramachandran plot allow peptide structures with successive residues having identical main chain conformations to be studied. We investigate repeating dipeptide main chain conformations and present Ramachandran plots encompassing the range of possible structures. Repeating dipeptides fall into the categories: rings, ribbons, and helices. Partial rings occur in the form of "nests" and "catgrips"; many nests are bridged by an oxygen atom hydrogen bonding to the main chain NH groups of alternate residues, an interaction optimized by the ring structure of the nest. A novel recurring feature is identified that we name unpleated β, often situated at the ends of a β-sheet strand. Some are partial rings causing the polypeptide to curve gently away from the sheet; some are straight. They lack β-pleat and almost all incorporate a glycine. An example is the first glycine in the GxxxxGK motif of P-loop proteins. Ribbons in repeating dipeptides can be either flat, as seen in repeated type II and type II' β-turns, or twisted, as in multiple type I and type I' β-turns. Hexa- and octa-peptides in such twisted ribbons occur frequently in proteins, predominantly with type I β-turns, and are the same as the "β-bend ribbons" hitherto identified only in short peptides. One is seen in the GTPase-activating protein for Rho in the active, but not the inactive, form of the enzyme. It forms a β-bend ribbon, which incorporates the catalytic arginine, allowing its side chain guanidino group to approach the active site and enhance enzyme activity., (Copyright © 2013 Wiley Periodicals, Inc.)