University of Graz

About: University of Graz is a education organization based out in Graz, Steiermark, Austria. It is known for research contribution in the topics: Population & Quantum chromodynamics. The organization has 17934 authors who have published 37489 publications receiving 1110980 citations. The organization is also known as: Carolo Franciscea Graecensis & Karl Franzens Universität.

Differential effects of capsaicin on the content of somatostatin, substance P, and neurotensin in the nervous system of the rat.

Abstract: The distribution of immunoreactive substance P (I-SP), somatostatin (I-SRIF), and neurotensin (I-NT) and the effect of capsaicin treatment on the concentration of these peptides was studied in the peripheral and central nervous system of the rat. Neonatal capsaicin treatment (50 mg/kg s.c.) caused a depletion of I-SRIF as well as of I-SP in sensory nerves and in the dorsal half of the spinal cord. No recovery of the peptide content was found when examined 4 months later suggesting an irrerersible effect. I-NT, not a constituent of primary sensory neurons, was not changed in the spinal cord. None of the peptides studied was depleted in the hypothalamus or preoptic area. Capsaicin treatment of adult rats also led to a decrease of I-SRIF and I-SP in primarh sensory neurons. The highest dose used (950 mg/kg s.c.) induced no greater depletion than the lowest one (50 mg/kg), except for I-SP in dorsal root ganglia. Intraperitoneal injection of capsaicin led to a higher degree of depletion than subcutaneous administration as examined 1 week after treatment. In contrast to neonatal treatment, the I-SRIF content was completely restored within 4 months after treatment of adult rats. The I-SP content, however, did not completely recover in all areas but remained reduced in cornea, vagus nerve, dorsal spinal cord, and medulla oblongata for up to 9 months. Intraventricular administration of capsaicin (200 μg) caused a depletion of I-SP in the medulla oblongata but had no effect on the content of all 3 peptides in hypothalamus or preoptic area. In contrast to systemic treatment, no depletion of I-SP or I-SRIF was found in the trigeminal ganglion. Chemosensitivity of the eye was abolished after intraventricular or systemic treatment. Repeated topical application of a capsaicin solution (10 mg/ml) to the eye led within 4 h to a nearly complete depletion of I-SP in the cornea. These experiments show that capsaicin treatment of rats caused a depletion of both I-SRIF and I-SP in primary sensory neurons. While topical or systemic capsaicin administration causes depletion in terminals, the failure of intraventricular injections of capsaicin to deplete the peptides in the trigeminal ganglion suggests that depletion of the entire neuron requires an action of capsaicin on the peripheral branch and/or the cell body.

The antimicrobial peptide SAAP-148 combats drug-resistant bacteria and biofilms

Abstract: Development of novel antimicrobial agents is a top priority in the fight against multidrug-resistant (MDR) and persistent bacteria. We developed a panel of synthetic antimicrobial and antibiofilm peptides (SAAPs) with enhanced antimicrobial activities compared to the parent peptide, human antimicrobial peptide LL-37. Our lead peptide SAAP-148 was more efficient in killing bacteria under physiological conditions in vitro than many known preclinical- and clinical-phase antimicrobial peptides. SAAP-148 killed MDR pathogens without inducing resistance, prevented biofilm formation, and eliminated established biofilms and persister cells. A single 4-hour treatment with hypromellose ointment containing SAAP-148 completely eradicated acute and established, biofilm-associated infections with methicillin-resistant Staphylococcus aureus and MDR Acinetobacter baumannii from wounded ex vivo human skin and murine skin in vivo. Together, these data demonstrate that SAAP-148 is a promising drug candidate in the battle against antibiotic-resistant bacteria that pose a great threat to human health.

Plasmon dispersion relation of Au and Ag nanowires

Abstract: We have studied surface plasmon modes on silver and gold nanowires of a fixed cross section and different lengths, produced by electron beam lithography. The optically excited modes are determined by extinction spectroscopy and can be interpreted in terms of standing plasmon polariton waves. The eigenfrequencies are found to follow a dispersion relation similar to that for a planar metal/dielectric interface.