TriTrap: A Robotic Gripper Inspired by Insect Tarsal Chains.

Gripping, holding, and moving objects are among the main functional purposes of robots. Ever since automation first took hold in society, optimizing these functions has been of high priority, and a multitude of approaches has been taken to enable cheaper, more reliable, and more versatile gripping. Attempts are ongoing to reduce grippers' weight, energy consumption, and production and maintenance costs while simultaneously improving their reliability, the range of eligible objects, working loads, and environmental independence.

Gripping performance in the stick insect Sungaya inexpectata in dependence on the pretarsal architecture.

Insect attachment devices and capabilities have been subject to research efforts for decades, and even though during that time considerable progress has been made, numerous questions remain. Different types of attachment devices are known, alongside most of their working principles, however, some details have yet to be understood. For instance, it is not clear why insects for the most part developed pairs of claws, instead of either three or a single one.

The anti-inflammatory effect of a pomegranate husk extract on inflamed adipocytes and macrophages cultivated independently, but not on the inflammatory vicious cycle between adipocytes and macrophages.

Obese adipose tissues contain a higher proportion of inflamed macrophages than the normal adipose tissue. Adipocytes and macrophages are known to secrete pro-inflammatory markers that establish the systemic inflammation leading to metabolic complications. CCL-2 secreted by hypertrophied adipocytes attracts and activates macrophages in the adipose tissue.

Anti-inflammatory effects of pomegranate (Punica granatum L.) husk ellagitannins in Caco-2 cells, an in vitro model of human intestine.

This study aimed at evaluating the anti-inflammatory properties of a pomegranate fruit husk (PomH) polyphenolic extract, rich in punicalagin, using Caco-2 cells, an in vitro model of human intestinal epithelium. Differentiated cells in bicameral inserts were pretreated or not with a PomH extract or punicalagin, as reference, at the apical side, representing the intestinal lumen. Inflammation was then induced with a cocktail of cytokines (Il-1β, TNFα and IFNγ) and LPS.

Natriuretic peptide receptors of type A in human neuroblastomas.

Functional natriuretic peptide receptors of type A (NPR-A) were detected in the human neuroblastoma NB-OK-1, SK-N-SH and SK-N-BE, but not the SH-SY5Y, cell lines. Also, NPR-A mRNA was detected in 19 of the 25 tumor neuroblastoma samples tested in this study. Five of the eight tumor neuroblastoma samples that were assayed for atrial natriuretic peptide (ANP) binding revealed the presence of ANP-binding sites.

Human A-type ANP receptor upregulation by PACAP and carbachol in neuroblastoma cells.

Pituitary adenylyl cyclase activating polypeptide (PACAP-27), forskoline and carbachol increased type A atrial natriuretic peptide receptor (NPR-A) density, as well as NPR-A mRNA level, in the human neuroblastoma NB-OK-1 cell line. TPA did not have any effect per se, but blunted the effect of PACAP-27 on both NPR-A density and NPR-A mRNA. The half-life of the NPR-A mRNA was not modified by any of the agents tested.

Ferritin-associated iron induces neutrophil dysfunction in hemosiderosis.

Neutrophils (PMNs) from patients with secondary iron overload have an increased iron and ferritin content as well as a phagocytosis defect. Several serum components might be incriminated in the cellular iron accumulation. We therefore compared the effects on the PMN phagocytosis of total serum as well as the ferritin and transferrin fractions of serum derived from patients with thalassemia major and healthy control subjects.

The pituitary adenylate cyclase activating polypeptide (PACAP I) and VIP (PACAP II VIP1) receptors stimulate inositol phosphate synthesis in transfected CHO cells through interaction with different G proteins.

The PACAP receptor (PACAP I receptor, selective for PACAP) and the PACAP II VIP1 receptor (recognizing PACAP and VIP with the same high affinity) were stably expressed in Chinese Hamster Ovary (CHO) cells. Cell lines expressing different receptor densities, as measured by binding saturation curves, were selected. Inositol phosphate production was stimulated dose dependently in all the cell lines by PACAP and VIP, and the order of potency of the agonists was identical to that of high affinity receptor occupancy.

Role of phosphodiesterase II in cross talk between cGMP and cAMP in human neuroblastoma NB-OK-1 cells.

Cyclic nucleotides levels and cyclic nucleotide phosphodiesterase (PDE) activities were measured in human neuroblastoma NB-OK-1 cells possessing atrial natriuretic peptide (ANP) receptors of the A type and pituitary adenylate cyclase activating polypeptide (PACAP)-preferring receptors. Adenosine 3',5'-cyclic monophosphate (cAMP) and guanosine 3',5'-cyclic monophosphate (cGMP) degradation were interrelated since the increase in cGMP, induced by ANP-(99-126), stimulated the hydrolysis of cAMP by PDE isoenzyme II. In intact NB-OK-1 cells, the levels of cAMP and cGMP attained in the presence of, respectively, 1 nM PACAP-(1-27) and 10 nM ANP-(99-126), and in the absence or presence of PDE inhibitors, strongly suggested that cAMP hydrolysis was mainly achieved by isoenzyme IV, and to a lesser extent by isoenzymes I, II, and III, while cGMP was degraded by isoenzymes I, II, III, and V.

Pituitary adenylate cyclase activating polypeptide (PACAP) and vasoactive intestinal peptide stimulate two signaling pathways in CHO cells stably transfected with the selective type I PACAP receptor.

The properties of the pituitary adenylate cyclase activating polypeptide (PACAP) type I receptor were studied on a clone of Chinese hamster ovary cells (CHO) stably transfected with the recombinant receptor. PACAP(1-27), PACAP(1-38) and VIP inhibited [125I-acetyl-His1]PACAP (1-27) binding, stimulated cyclic AMP and inositol phosphates production and induced [Ca2+]i increase with the same order of potency: PACAP(1-27) = PACAP(1-38) > VIP. The concentrations required for half maximal receptor occupancy, IP3- and [Ca2+]i increase were not different for both PACAPs (1 nM) and 100-fold higher than those required for cyclic AMP increase (0.

New evidence for a membrane-bound pathway in hormone receptor binding.

The fully active cholecystokinin analog (Thr,Nle)-CCK-9 was lipo-derivatized by N-terminal grafting of a dimyristoylglycerol moiety to induce tight interdigitation with cell membrane bilayers. While the parent CCK peptide was shown to interact only transiently with small unilamellar phospholipid vesicles, the lipo-CCK peptide, although self-aggregating into vesicles, inserts rapidly and quantitatively into phospholipid bilayers. Fluorescence and, even more so, NMR data are supportive for a chain reversal of the CCK moiety of the lipo derivative with embedment of the C-terminus into hydrophobic compartments of the bilayer.

Contrasting effects of PACAP and carbachol on [Ca2+]i and inositol phosphates in human neuroblastoma NB-OK-1 cells.

The effects of PACAPs on [Ca2+]i were compared to those of carbachol in human neuroblastoma NB-OK-1 cells. PACAP(1-27) and PACAP(1-38) increased [Ca2+]i in a biphasic manner: a transient rise and a secondary plateau. The transient phase reflected the mobilization of [Ca2+]i pool(s) via the inositol phosphate pathway.

Regulation of Na-K-Cl cotransport, Na,K-adenosine triphosphatase, and Na/H exchanger in human neuroblastoma NB-OK-1 cells by atrial natriuretic peptide.

The occupancy of atrial natriuretic peptide (ANP) receptors of the ANPA type in human neuroblastoma NB-OK-1 cells elevates cGMP. In this study, ANP concentrations of 10 nM or more increased total K+ uptake. Data obtained in the presence of bumetanide and/or ouabain demonstrated that 1 microM ANP induced a primary stimulation (by 82%) of Na-K-Cl cotransport and a subsequent indirect stimulation (by 15%) of Na,K-ATPase.

Discovery of a potent atrial natriuretic peptide antagonist for ANPA receptors in the human neuroblastoma NB-OK-1 cell line.

The effects of seven competitive atrial natriuretic peptide (ANP) receptor antagonists were compared on cultured human neuroblastoma NB-OK-1 cells expressing exclusively ANPA receptors, by evaluating their capacity to inhibit [125I]ANP binding and to suppress ANP-stimulated cyclic GMP elevation. In ANP analogues with a shortened Cys7-Cys18 bridge, Asp13 and a hydrophobic Tic residue at position 16 expressed antagonistic activity, while Ala16 provoked lower antagonistic potency and Phe16 induced receptor activation. The binding affinity of A71915 ([Arg6, Cha8]ANP-(6-15)-D-Tic-Arg-Cys-NH2), the most potent antagonist (with a pKi of 9.

Atrial natriuretic peptide binds to ANP-R1 receptors in neuroblastoma cells or is degraded extracellularly at the Ser-Phe bond.

ANP-R1 receptors for atrial natriuretic peptide (ANP) showed the following rank order of affinity in intact human neuroblastoma cells NB-OK-1: human ANP-(99-126) approximately human ANP-(102-126) approximately rat ANP-(99-126) (K1 17-32 pM) > human ANP-(103-126) > porcine brain natriuretic peptide (BNP). Analogues truncated at the C-terminal extremity or devoid of a disulphide bridge, such as rat ANP-(103-123), rat C-ANP-(102-121), rat ANP-(111-126), rat ANP-(99-109) and rat [desCys105,Cys121]ANP-(104-126) and chicken C-type natriuretic peptide, were not recognized. The occupancy of these high affinity ANP-R1 receptors led to marked cyclic GMP accumulation in the presence of 3-isobutyl 1-methylxanthine.

Inhibitory effects of ATP and other nucleotides on atrial natriuretic peptide (ANP) binding to R1-type ANP receptors in human neuroblastoma NB-OK-1 cell membranes.

ATP dose-dependently inhibited rat 125I-ANP-(99-126) binding to membranes from the human neuroblastoma cell line NB-OK-1 by increasing the KD value for the hormone without altering the Bmax value. After a 20 min preincubation with 37.5 pM 125I-ANP-(99-126) and 0.

A new metallo- endopeptidase from human neuroblastoma NB-OK-1 cells which inactivates atrial natriuretic peptide by selective cleavage at the Ser123-Phe124 bond.

A novel metallo-endopeptidase from human neuroblastoma NB-OK-1 cells was partially purified and characterized. This enzyme activity was detected in the culture medium and could be detached from intact cells by gentle washing, suggesting a peripheral localization of the enzyme. This endopeptidase inactivated Atrial Natriuretic Peptide (ANP) by a unique and selective cleavage of the Ser123-Phe124 bond.

Functional cholecystokinin receptors are distinguished kinetically by biotinyl-Tyr-Gly-(Thr28,Nle31)CCK(25-33) in rat pancreatic acini.

Biotinyl-tyrosine-glycine(Thr28,Nle31)CCK(25-33) (BTG-TN-CCK-9) promoted amylase secretion and phosphatidylinositol (PI) metabolism with the same potency and efficacy as TN-CCK-9 in dispersed rat pancreatic acini. A 1 min preincubation of the ligand with a 20-fold excess of streptavidin completely suppressed this biological activity. On the other hand, amylase secretion and PI metabolism prestimulated with BTG-TN-CCK-9 were blocked within 1-5 min after streptavidin addition.

Characterization and regulation of atrial natriuretic peptide (ANP)-R1 receptors in the human neuroblastoma cell line NB-OK-1.

We characterized in membranes from the human neuroblastoma cell line NB-OK-1, an ANP-R1 receptor (Mr 130 kDa) for the atrial natriuretic peptide (ANP). This receptor recognized biologically active forms of ANP with high affinity but showed no affinity for truncated ANP forms. It was functional in that binding correlated with guanylate cyclase activation (a 2-fold increase in Vmax) with the following rank order of potency: rat ANP-(99-126) greater than human ANP-(99-126) greater than human ANP-(102-126) greater than porcine BNP (brain natriuretic peptide).

The metabolic effects of guanyl nucleotides on rat pancreatic acini permeabilized with streptolysin O suggest a widespread use of G proteins.

In streptolysin O permeabilized acini that were normally responsive to carbamylcholine and cholecystokinin octapeptide, amylase secretion was stimulated: a) by the stable guanyl nucleotides with a potency decreasing as follows: guanosine 5'-O-(3-thiotriphosphate) (GTP gamma S) greater than guanylyl-imidodiphosphate (GMP-PNP) = guanylyl-(beta, gamma-methylene)-diphosphonate (GMP-PCP), in the presence of 0.5 mM calcium and b) by calcium alone (EC50 3 microM). The maximal secretory effect of calcium alone (a 2-fold increase) was less effective than that of GTP gamma S and calcium offered in combination (an 8-fold increase).

Purification and characterization of five variants of phospholipase A2 and complete primary structure of the main phospholipase A2 variant in Heloderma suspectum (Gila monster) venom.

1. Five increasingly anionic variants (Pa1-Pa5) of Ca2+-dependent phospholipase A2 were purified to homogeneity from the venom of the lizard Heloderma suspectum (Gila monster). The purification procedure was based on semi-preparative reverse-phase HPLC followed by anion-exchange HPLC and analytical reverse-phase HPLC.

Functional characterization of muscarinic receptors in rat parotid acini.

The muscarinic agonist, carbamylcholine, stimulated amylase secretion in rat parotid acini 6-fold, the 86Rb efflux 5-fold, the 45Ca efflux 5-fold and the accumulation of inositol monophosphate, bisphosphate, trisphosphate and tetrakisphosphate 4-, 4-, 3- and 3-fold, respectively. The EC50 of carbamylcholine on these parameters were 0.4, 0.

Species differences in the molecular characteristics of vasoactive-intestinal-peptide receptors in the pancreas from rat and guinea-pig.

1. The receptors for vasoactive intestinal peptide (VIP) present in dispersed acini and membranes from rat and guinea-pig pancreas differed in selectivity pattern, i.e.

Vasoactive intestinal peptide receptors in pancreas and liver. Structure-function relationship.

In purified rat pancreatic plasma membranes, (D-Phe4)PHI interacts as a selective VIP agonist for rat pancreatic VIP-preferring receptors, based on binding selectivity and adenylate cyclase activation, therefore allowing us to discriminate between the participation of VIP-preferring and secretin-preferring receptors in VIP stimulation. VIP-preferring receptors also bind GRF. They rely on disulfide bridges for their functional integrity.