The effect of lactic acid on the outer membrane permeability of Escherichia coli O157:H7, Pseudomonas aeruginosa, and Salmonella enterica serovar Typhimurium was studied utilizing a fluorescent-probe uptake assay and sensitization to bacteriolysis. For control purposes, similar assays were performed with EDTA (a permeabilizer acting by chelation) and with hydrochloric acid, the latter at pH val...

For more than 20 years the use of media containing potassium cyanide (KCN) has been advocated in the study of enteric bacteria. Braun and Guggenheim (1932) and Braun (1938, 1939) noted that cultures of the Klebsiella-Aerobacter group were able to grow in concentrations of KCN which inhibited Escherichia coli. Buttiaux (1952) employed the medium of Braun in the study of 280 Salmonella cultures a...

Cyanide inhibits aerobic metabolism by binding to the binuclear heme center of cytochrome c oxidase (CcOX). Amyl nitrite and sodium nitrite (NaNO(2)) antagonize cyanide toxicity in part by oxidizing hemoglobin to methemoglobin (mHb), which then scavenges cyanide. mHb generation is thought to be a primary mechanism by which the NO(2)(-) ion antagonizes cyanide. On the other hand, NO(2)(-) can un...

Paradoxically, in eukaryotic cells, hydrogen peroxide (H(2)O(2)) accumulates in response to oxygen deprivation (hypoxia). The source of H(2)O(2) under hypoxia varies according to the species, organs, and tissue. In non-photosynthetic tissues, H(2)O(2) is mainly produced by activation of NAD(P)H-oxidases or by disruption of the mitochondrial electron transport chain (m-ETC). This study showed th...

PURPOSE To report changing trends in indications and techniques of corneal transplantation in Iran. METHODS We reviewed eye bank records of 47,129 patients who had undergone corneal transplantation between 2006 and 2013 at different eye centers throughout Iran. RESULTS The most common indication for corneal transplantation was keratoconus (KCN, n = 21,350 eyes, 45.3%), followed by bullous k...

lipoxygenase(lox) catalyzes irreversible transfer of oxygen molecule to arachidonic and linoleic acid to produce 13 hydroproxy octadecadienoic acid. recent studies showed the involvement of lipoxygenase products, leukotrienes, in inflammations and lipoxygenase pathways acts as mediators of early inflammatory events in atherosclerosis. the aim of the present study was purification and characteri...

Stabilized melanocortin analog peptide ACTH(6–9)PGP (HFRWPGP) possesses a wide range of neuroprotective activities. However, its mechanism action remains poorly understood. In this paper, we present study the proproliferative and cytoprotective activity adrenocorticotropic hormone fragment 6–9 (HFRW) linked with prolyine–glycyl–proline on SH-SY5Y cells in model oxidative stress-related toxicity...

purpose: to evaluate changes in indications of corneal transplantation at labbafinejad medical center during 2001-2003. methods: records of 563 from 684 patients who had undergone corneal transplantation from oct. 2001 to oct. 2003 were evaluated. all the procedures were performed by corneal surgeons and fellows. findings: there were 292 male (51.9%) and 217 female (48.1%) subjects ranging in a...