Cyclic nucleotide-gated channels are important in visual and olfactory transduction, and possibly in other neuronal functions. These channels have a complex permeability to Ca2+ ions that may be important in their cellular functions. They are composed of two different subunits, alpha and beta, that have been cloned and expressed, but the beta subunit alone cannot be activated by cyclic nucleoti...

1. Gluconeogenesis from pyruvate was measured in renal-cortical-tubules fragments prepared from fed male rats 6-8 days after adrenalectomy or sham adrenalectomy. The response of this process to 3':5'-cyclic AMP and adrenaline was compared in these two states at two Ca2+ concentrations. 2. Adrenalectomy decreased the percentage stimulation of gluconeogenesis by 3':5'-cyclic AMP, but increased pe...

To understand the structural and chemical basis for insect neuropeptide activity, we have designed, synthesized, and determined the conformation of a biologically active cyclic analog of the pyrokinins, an insect neuropeptide family that mediates myotropic (visceral muscle contractile) activity. Members of this insect neuropeptide family share the common C-terminal pentapeptide sequence Phe-Xaa...

Definitions: Beta-lactam antimicrobials are characterized by having a four-membered cyclic amide (beta-lactam ring) as part of their chemical structure (Figure 1) [1]. This broad group includes the penicillins, cephalosporins, carbapenems, and monobactams [1]. All beta-lactams have a similar mechanism of action; they inhibit bacterial cell wall synthesis [1]. Resistance to beta-lactam antimicro...

In this paper, we prove some fixed point results in the setting of a Banach space via cyclic \((\alpha ,\beta ,z)\)-admissible mapping imbedded simulation function. Our extend and generalize well known existing literature.

A novel amphoteric glycosphingolipid, cholinephosphoryl-(-->6)-beta-D-GlcpNAc-(1-->3)-beta-D-Manp-(1-->4)-beta-D-Glcp-(1-->)-Cer, isolated from the porcine parasitic nematode, Ascaris suum, may be expected to be involved in host-parasite interactions. This glycosphingolipid analogue containing octyl residue in place of ceramide was synthesized as follows: The key reaction of this synthetic proc...

Cepacidine A is a novel glycopeptide with a potent antifungal activity, which is produced by Pseudomonas cepacia AF 2001. Its molecular weight was determined by FAB-MS (m/z 1215). The compound is comprised of glycine (1), serine (2), 2,4-diaminobutyric acid (1), aspartic acid (1), beta-hydroxy tyrosine (1), beta-hydroxy asparagine (1), xylose (1) and 5,7-dihydroxy-3,9-diamino-octadecanoic acid ...

The COOH-terminal octapeptide of cholecystokinin (CCK-OP) and carbamylcholine each increased calcium outflux, cellular cyclic GMP and amylase secretion in dispersed guinea pig pancreatic acinar cells. Following addition of CCK-OP or carbamylcholine, cellular cyclic GMP increased as early as 15 s, became maximal after 1 to 2 min, and then decreased steadily during the subsequent incubation. For ...

In the present study, we evaluated the physiological responsiveness of the increased numbers of beta-adrenergic receptors in ischemic canine myocardium to in vivo stimulation by (-)-isoproterenol and epinephrine. After 1 hour of temporary proximal left anterior descending coronary artery occlusion and during a 15-minute period of reflow, dogs received (1)-isoproterenol intravenously at a rate s...