István Bátai

Occurrence of hlyA and sheA Genes in Extraintestinal Escherichia coli Strains

ABSTRACT The association of a hemolytic phenotype with the carriage of the α-hemolysin gene (hlyA) and/or the silent hemolysin gene (sheA or clyA) among 540 extraintestinal clinical isolates of Escherichia coli and 110 fecal isolates from healthy individuals was investigated. Though HlyA is an important virulence factor in extraintestinal E. coli infection, the role of SheA is not completely clarified. Two hemolytic sheA+E. coli strains that lacked hlyA and possessed no other hemolysin genes were identified. No hlyA+sheA+ strains were identified, suggesting that there is possible incompatibility between hlyA and sheA in the chromosome of E. coli.

Bacterial growth in ropivacaine hydrochloride.

IMPLICATIONS Drugs affecting bacterial growth may influence the occurrence of postoperative infections. Ropivacaine 10 mg/mL killed Staphylococcus aureus and Escherichia coli; ropivacaine 2 mg/mL supported the growth of E. coli.

PACAP Application Improves Functional Outcome of Chronic Retinal Ischemic Injury in Rats-Evidence From Electroretinographic Measurements

Retinoprotective effects of pituitary adenylate cyclase activating polypeptide (PACAP) are well-known and have been demonstrated in various pathological conditions, such as diabetic retinopathy, excitotoxic retinal injury, UV light-induced degeneration, and ischemic retinal lesion. The neuronal degeneration observed in the different retinal layers under the above pathological conditions can be successfully decreased by PACAP; however, whether this morphological improvement is also reflected in functional amelioration remains unknown. Therefore, our purpose was to investigate the protective effect of PACAP on the rat retina after bilateral common carotid artery occlusion (BCCAO) with electroretinography (ERG) to parallel the functional data with the previous morphological and neurochemical observations. Control eyes received saline treatment while PACAP was injected into the vitreous space of the other eye immediately after the induction of ischemia. Retinal damage and protective effects of PACAP were quantified by the changes in the wave forms and amplitudes. On postoperative days 2 and 14, several parameters were assessed with special attention to the changes of b wave. The results confirm that the previously described morphological protection induced by PACAP treatment is reflected in functional improvement in ischemic retinal lesions.

A comparison of the antimicrobial property of lidocaine/prilocaine cream (EMLA®) and an alcohol-based disinfectant on intact human skin flora.

BACKGROUND: The application of EMLA® cream is indicated for topical anesthesia of the skin in connection with IV cannulation. Recently, we described that EMLA cream has an antibacterial effect in vitro. METHODS: The impact of the local anesthetic lidocaine/prilocaine cream (EMLA) on intact human skin flora was compared to that of an alcohol-based skin disinfectant (Skinsept Pur®). Samples were taken from 0 to 12 h after treatment. RESULTS: The number of colony forming units (cfu) on the skin decreased significantly after both EMLA and Skinsept Pur treatment from 44.9 ± 1.3 (42.4 ± 7.0) to 0.9 ± 0.17 (1.61 ± 0.47) cfu/cm2, respectively (mean ± sem), at the first sampling time (1 h) and remained significantly below 0 h values for the study period. The cfu count was significantly lower with EMLA cream at 4, 6, and 12 h compared to Skinsept Pur. CONCLUSION: EMLA cream has a longer bacteriostatic effect after early bactericidal impact compared to skin disinfection with Skinsept Pur.

Capsaicin-Sensitive Sensory Nerves Mediate the Cellular and Microvascular Effects of H2S via TRPA1 Receptor Activation and Neuropeptide Release.

It is supposed that TRPA1 receptor can be activated by hydrogen sulphide (H2S). Here, we have investigated the role of TRPA1 receptor in H2S-induced [Ca2+]i increase in trigeminal ganglia (TRG) neurons, and the involvement of capsaicin-sensitive sensory nerves in H2S-evoked cutaneous vasodilatation. [Ca2+]i was measured with ratiometric technique on TRG neurons of TRPA1+/+ and TRPA1−/− mice after NaHS, Na2S, allylisothiocyanate (AITC) or KCl treatment. Microcirculatory changes in the ear were detected by laser Doppler imaging in response to topical NaHS, AITC, NaOH, NaSO3 or NaCl. Mice were either treated with resiniferatoxin (RTX), or CGRP antagonist BIBN4096, or NK1 receptor antagonist CP99994, or K+ATP channel blocker glibenclamide. Alpha-CGRP−/− and NK1−/− mice were also investigated. NaHS and Na2S increased [Ca2+]i in TRG neurons derived from TRPA+/+ but not from TRPA1−/− mice. NaHS increased cutaneous blood flow, while NaOH, NaSO3 and NaCl did not cause significant changes. NaHS-induced vasodilatation was reduced in RTX-treated animals, as well as by pre-treatment with BIBN4096 or CP99994 alone or in combination. NaHS-induced vasodilatation was significantly smaller in alpha-CGRP−/− or NK1−/− mice compared to wild-types. H2S activates capsaicin-sensitive sensory nerves through TRPA1 receptors and the resultant vasodilatation is mediated by the release of vasoactive sensory neuropeptides CGRP and substance P.

Role of Transient Receptor Potential Ankyrin 1 Ion Channel and Somatostatin sst4 Receptor in the Antinociceptive and Anti-inflammatory Effects of Sodium Polysulfide and Dimethyl Trisulfide

Transient receptor potential ankyrin 1 (TRPA1) non-selective ligand-gated cation channels are mostly expressed in primary sensory neurons. Polysulfides (POLYs) are Janus-faced substances interacting with numerous target proteins and associated with both protective and detrimental processes. Activation of TRPA1 in sensory neurons, consequent somatostatin (SOM) liberation and action on sst4 receptors have recently emerged as mediators of the antinociceptive effect of organic trisulfide dimethyl trisulfide (DMTS). In the frame of the present study, we set out to compare the participation of this mechanism in antinociceptive and anti-inflammatory effects of inorganic sodium POLY and DMTS in carrageenan-evoked hind-paw inflammation. Inflammation of murine hind paws was induced by intraplantar injection of carrageenan (3% in 30 µL saline). Animals were treated intraperitoneally with POLY (17 µmol/kg) or DMTS (250 µmol/kg) or their respective vehicles 30 min prior paw challenge and six times afterward every 60 min. Mechanical pain threshold and swelling of the paws were measured by dynamic plantar aesthesiometry and plethysmometry at 2, 4, and 6 h after initiation of inflammation. Myeloperoxidase (MPO) activity in the hind paws were detected 6 h after challenge by luminescent imaging. Mice genetically lacking TRPA1 ion channels, sst4 receptors and their wild-type counterparts were used to examine the participation of these proteins in POLY and DMTS effects. POLY counteracted carrageenan-evoked mechanical hyperalgesia in a TRPA1 and sst4 receptor-dependent manner. POLY did not influence paw swelling and MPO activity. DMTS ameliorated all examined inflammatory parameters. Mitigation of mechanical hyperalgesia and paw swelling by DMTS were mediated through sst4 receptors. These effects were present in TRPA1 knockout animals, too. DMTS inhibited MPO activity with no participation of the sensory neuron–SOM axis. While antinociceptive effects of POLY are transmitted by activation of peptidergic nerves via TRPA1, release of SOM and its effect on sst4 receptors, those of DMTS partially rely on SOM release triggered by other routes. SOM is responsible for the inhibition of paw swelling by DMTS, but TRPA1 does not contribute to its release. Modulation of MPO activity by DMTS is independent of TRPA1 and sst4.

Effects of sulfide and polysulfides transmitted by direct or signal transduction-mediated activation of TRPA1 receptors: TRPA1-mediated effects of sulfide and polysulfides

Hydrogen sulfide (H2S) is a gaseous mediator in various physiological and pathological processes, including neuroimmune modulation, metabolic pathways, cardiovascular system, tumour growth, inflammation and pain. Now the hydrogen polysulfides (H2Sn) have been recognised as signalling molecules modulating ion channels, transcription factors and protein kinases. Transient receptor potential (TRP) cation channels can be activated by mechanical, thermal or chemical triggers. Here, we review the current literature regarding the biological actions of sulfide and polysulfide compounds mediated by TRP channels with special emphasis on the role of TRPA1, best known as ion channels in nociceptors. However, the non‐neuronal TRPA1 channels should also be considered to play regulatory roles. Although sulfide and polysulfide effects in different pathological circumstances and TRPA1‐mediated processes have been investigated intensively, our review attempts to present the first comprehensive overview of the potential crosstalk between TRPA1 channels and sulfide‐activated signalling pathways.

Atropine and glycopyrrolate do not support bacterial growth—safety and economic considerations

STUDY OBJECTIVE Evaluation of bacterial growth in atropine and glycopyrrolate. DESIGN Laboratory investigation. SUBJECTS AND MEASUREMENTS Standard microbiological methods were used to evaluate the impact of atropine and glycopyrrolate on the growth of Acinetobacter baumannii, Pseudomonas aeruginosa, Staphylococcus aureus, and Escherichia coli. Bacterial count was checked at 0, 1, 2, 3, 4, 6, and 24 hours. MAIN RESULTS Atropine or glycopyrrolate did not support the growth of the above bacteria at any examined time at room temperature. Glycopyrrolate killed all of the examined strains (P < .05), whereas in atropine, only the clinical isolates of Staphylococcus and Acinetobacter were killed (P < .05). CONCLUSIONS Drawing up atropine or glycopyrrolate at the beginning of the operating list and use within 24 hours if needed are a safe practice and do not pose infection hazard. We can also reduce hospital costs if we do not throw away these unused syringes following each case.