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We presented intracardiac electrograms during the parahisian pacing, which represent three types of retrograde conduction and focus on the mechanism of types of retrograde conduction on wide QRS complexes and conclude that the two types of QRS of the retrograde conduction resulted from the presence or absence of retrograde block at the right bundle branch.

Monocyte-high density lipoprotein ratio (MHR) has recently emerged as a marker of inflammation and oxidative stress in the cardiovascular disease. We aimed to investigate whether baseline MHR is associated with functional significance of intermediate coronary artery lesions.

The ‘smoker's paradox’ refers to the observation of favorable prognosis in current smokers following an acute ST elevation myocardial infarction (STEMI) in the era of fibrinolysis, however, several STEMI studies have demonstrated conflicting results in patients undergoing primary percutaneous coronary intervention (p-PCI).

The transition of the tachycardia from narrow to wide by a spontaneous atrial premature contraction causing a long‐short sequence and right bundlebranch block

ObjectiveIatrogenic femoral pseudoaneurysm is a well-known vascular access site complication. Many invasive and noninvasive techniques have been proposed for the management of this relatively common complication. In this study, we aimed to evaluate effi ciency and safety of stethoscopeguided compression as a novel noninvasive technique in the femoral pseudoaneurysm treatment.Methods and resultsWe prospectively included 29 consecutive patients with the diagnosis of femoral pseudoaneurysm who underwent coronary angiography. Patients with a clinical suspicion of femoral pseudoaneurysm were referred to colour Doppler ultrasound evaluation. The adult (large) side of the stethoscope was used to determine the location where the bruit was best heard. Then compression with the paediatric (small) side of the stethoscope was applied until the bruit could no longer be heard and compression was maintained for at least two sessions. Once the bruit disappeared, a 12-hour bed rest with external elastic compression was advised to the patients, in order to prevent disintegration of newly formed thrombosis. Mean pseudoaneurysm size was 1.7 ± 0.4 cm × 3.0 ± 0.9 cm and the mean duration of compression was 36.2 ± 8.5 minutes. Twenty-six (89.6%) of these 29 patients were successfully treated with stethoscope-guided compression. In 18 patients (62%), the pseuodoaneurysms were successfully closed after 2 sessions of 15-minute compression. No severe complication was observed.ConclusionStethoscope-guided compression of femoral pseudoaneurysms is a safe and eff ective novel technique which requires less equipment and expertise than other contemporary methods.

Anincreased circulating monocyte count has been found to be related to good collateral development in patients with stable coronary artery disease. Our aim in this study was to determine any possible relationship between the levels of circulating monocyte subsets and coronary collateral development.

Our aims were to evaluate the efficacy of ozone therapy (OT) in an experimental rat model of acute necrotizing pancreatitis (ANP) and to compare its effects with hyperbaric oxygen (HBO) therapy in this entity.

Molecular, genetic and epigenetic pathways of peroxynitrite-induced cellular toxicityOxidative stress plays a key role in the pathogenesis of cancer and many metabolic diseases; therefore, an effective antioxidant therapy would be of great importance in these circumstances. Nevertheless, convincing randomized clinical trials revealed that antioxidant supplementations were not associated with significant reduction in incidence of cancer, chronic diseases and all-cause mortality. As oxidation of essential molecules continues, it turns to nitro-oxidative stress because of the involvement of nitric oxide in pathogenesis processes. Peroxynitrite damages via several distinctive mechanisms; first, it has direct toxic effects on all biomolecules and causes lipid peroxidation, protein oxidation and DNA damage. The second mechanism involves the induction of several transcription factors leading to cytokine-induced chronic inflammation. Finally, it causes epigenetic perturbations that exaggerate nuclear factor kappa-B mediated inflammatory gene expression. Lessons-learned from the treatment of several chronic disorders including pulmonary diseases suggest that, chronic inflammation and glucocorticoid resistance are regulated by prolonged peroxynitrite production.

Chronically-elevated blood glucose initiates a harmful series of processes in which toxic reactive species play crucial roles. Oxidative as well as nitro-oxidative stress is harmful for virtually all biomolecules including lipids, proteins and DNA. Such pathophysiologic mechanisms eventually results in cellular dysfunction, apoptosis or necrosis. Melatonin is a multifunctional indolamine which counteracts several pathophysiologic steps and displays significant beneficial effects against hyperglycemia-induced cellular toxicity. These are related to melatonins antioxidative, anti-inflammatory and possibly epigenetic regulatory properties. Current knowledge encourages using this non-toxic indolamine either as a sole treatment or in conjunction with other treatments for inhibition of the biohazards of hyperglycemia.

Melatonin combats molecular terrorism at the mitochondrial levelThe intracellular environmental is a hostile one. Free radicals and related oxygen and nitrogen-based oxidizing agents persistently pulverize and damage molecules in the vicinity of where they are formed. The mitochondria especially are subjected to frequent and abundant oxidative abuse. The carnage that is left in the wake of these oxygen and nitrogen-related reactants is referred to as oxidative damage or oxidative stress. When mitochondrial electron transport complex inhibitors are used, e.g., rotenone, 1-methyl-1-phenyl-1,2,3,6-tetrahydropyridine, 3-nitropropionic acid or cyanide, pandemonium breaks loose within mitochondria as electron leakage leads to the generation of massive amounts of free radicals and related toxicants. The resulting oxidative stress initiates a series of events that leads to cellular apoptosis. To alleviate mitochondrial destruction and the associated cellular implosion, the cell has at its disposal a variety of free radical scavengers and antioxidants. Among these are melatonin and its metabolites. While melatonin stimulates several antioxidative enzymes it, as well as its metabolites (cyclic 3-hydroxymelatonin, N1-acetyl-N2-formyl-5-methoxykynuramine and N1-acetyl-5-methoxykynuramine), likewise effectively neutralize free radicals. The resulting cascade of reactions greatly magnifies melatonin's efficacy in reducing oxidative stress and apoptosis even in the presence of mitochondrial electron transport inhibitors. The actions of melatonin at the mitochondrial level are a consequence of melatonin and/or any of its metabolites. Thus, the molecular terrorism meted out by reactive oxygen and nitrogen species is held in check by melatonin and its derivatives.

Epigenetic perturbations in the pathogenesis of mustard toxicity; hypothesis and preliminary resultsAmong the most readily available chemical warfare agents, sulfur mustard (SM), also known as mustard gas, has been the most widely used chemical weapon. SM causes debilitating effects that can leave an exposed individual incapacitated for days to months; therefore delayed SM toxicity is of much greater importance than its ability to cause lethality. Although not fully understood, acute toxicity of SM is related to reactive oxygen and nitrogen species, oxidative stress, DNA damage, poly(ADP-ribose) polymerase (PARP) activation and energy depletion within the affected cell. Therefore several antioxidants and PARP inhibitors show beneficial effects against acute SM toxicity. The delayed toxicity of SM however, currently has no clear mechanistic explanation. One third of the 100,000 Iranian casualties are still suffering from the detrimental effects of SM in spite of the extensive treatment. We, therefore, made an attempt whether epigenetic aberrations may contribute to pathogenesis of mustard poisoning. Preliminary evidence reveals that mechlorethamine (a nitrogen mustard derivative) exposure may not only cause oxidative stress, DNA damage, but epigenetic perturbations as well. Epigenetic refers to the study of changes that influence the phenotype without causing alteration of the genotype. It involves changes in the properties of a cell that are inherited but do not involve a change in DNA sequence. It is now known that in addition to mutations, epimutations contribute to a variety of human diseases. Under light of preliminary results, the current hypothesis will focus on epigenetic regulations to clarify mustard toxicity and the use of drugs to correct possible epigenetic defects.

Acute and delayed sulfur mustard toxicity; novel mechanisms and future studiesSulfur mustard (SM), also known as mustard gas, has been the most widely used chemical weapon. The toxicity of SM as an incapacitating agent is of much greater importance than its ability to cause lethality. Acute toxicity of SM is related to reactive oxygen and nitrogen species, DNA damage, poly(ADP-ribose) polymerase activation and energy depletion within the affected cell. Therefore melatonin shows beneficial effects against acute SM toxicity in a variety of manner. It scavenges most of the oxygen- and nitrogen-based reactants, inhibits inducible nitric oxide synthase, repairs DNA damage and restores cellular energy depletion. The delayed toxicity of SM however, currently has no mechanistic explanation. We propose that epigenetic aberrations may be responsible for delayed detrimental effects of mustard poisoning. Epigenetic refers to the study of changes that influence the phenotype without causing alteration of the genotype. It involves changes in the properties of a cell that are inherited but do not involve a change in DNA sequence. It is now known that in addition to genetic mutations, epimutations can also involve in the pathogenesis of a variety of human diseases. Several actions of melatonin are now delineated by epigenetic actions including modulation of histone acetylation and DNA methylation. Future studies are warranted to clarify whether epigenetic mechanisms are involved in pathogenesis of delayed sulfur mustard toxicity and melatonin alleviates delayed toxicity of this warfare agent.

Background: Hyperbaric oxygen (HBO) is known to cause oxidative stress in several organs and tissues. We previously defined the pressure-related oxidative effects of HBO in several tissues of rats. This study was performed to elucidate the relationship of HBO exposure time to its oxidative effects. Methods: A total of 49 rats were randomly divided into 5 groups. Study groups were subjected to 3 atm HBO for 30, 60, 90, and 120 min except the control group. Their blood and lungs were removed immediately after exposure and used for analysis. Thiobarbituric acid reactive substances (TBARS), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) levels were determined to reflect oxidant and antioxidant status. Results: TBARS levels were found to increase in a time-dependent manner in both erythrocytes [median (min-max); from 0.65 (0.39-0.84) with 30 mm HBO exposure up to 1.26 (1.00-1.44) nmol · g-1 hemoglobin after 120 min] and lung tissue [from 2140(1550-2510) up to 5465 (5090-5950) nmol g-1 protein]. Similarly, SOD activity also presented a dose-dependent course from 0.06 (0.05-0.10) to 0.18 (0.14-0.26) U -1 g-1 hemoglobin in erythrocytes and from 16,660 (3479-25,994) to 52,522.5 (41,362-65,799) U -1 g-1 protein in lung tissue. In contrast, GSH-Px activity reflected an irregular trend; its levels were mostly found to be increased, but they were decreased at one stage (in the erythrocytes of 30-min exposed rats). Conclusions: The results of this study exhibited a clear relationship of HBO-induced oxidative action to exposure time. This action was most pronounced from 90 to 120 min of exposure. [ABSTRACT FROM AUTHOR]

Differential diagnoses of regularly irregular narrow QRS tachycardias are AV re‐entrant tachycardia (AVRT) with alternating antegrade AVN pathways, atypical AV nodal re‐entrant tachycardia (AVNRT) with alternating antegrade AVN pathways, and atrial tachycardia (AT) with alternating antegrade AVN pathways or with Wenckebach periodicity.

Abstract

Abstract This study was designed to investigate the effects of chronic toluene inhalation in high concentration on lipid peroxidation, antioxidant enzyme activities and ultrastructural changes in the sciatic nerves of rats. Male Wistar albino rats (150–250 g) were divided in two experimental groups: the control and the toluene treated group ( n =10 for each). Toluene treatment was performed by inhalation of 3000 ppm toluene, in a 8 h/day and 6 day/week order for 16 weeks. Blood and tissue samples were obtained for biochemical and histopathological investigation. The blood and sciatic nerves were assayed for toluene by gas chromatography. Toluene significantly increased blood and tissue malondialdehyde (MDA), and decreased tissue superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), but not tissue catalase (CAT) levels when compared with controls. Electron micrographs of sciatic nerve in the toluene group shows myelin destructions with onion-bulb and bubble form protrusion on the myelin sheath and axolemma border of myelinated axons. The area of injury on the myelin sheath were measured by Image-Pro Plus. Mean of the injury area were estimated 34% each myelin. These findings indicate that chronic toluene inhalation might be involved with free radical processes.

The effects of stratification and priming on germination and emergence performance of narrow-leafed purple coneflower (Echinacea angustifolia) seeds were investigated. Seeds were pre-chilled for 3 weeks at 4 ± 0.5 °C (39.2 ± 0.9 °F) in light or primed for 3 days at 20 ± 0.5 °C (68.0 ± 0.9 °F) in darkness in Nas and Read medium (NRM) or in 2% potassium nitrate (KNO3) supplemented with 3 or 5 μM 1-aminocyclopropane carboxylic acid (ACC) or 500 mg·L-1 (ppm) or 1000 mg·L-1 gibberellic acid (GA3). Following stratification and priming, seeds were subjected to germination and emergence tests at 25 ± 0.5 °C (77.0 ± 0.9 °F). Priming the seeds in NRM or KNO3 containing 3 μM ACC gave the highest germination percentages with 78% and 80%, respectively. Stratification alone increased germination to 69% compared to nontreated seeds, which had the lowest germination percentage of 57%. Emergence was enhanced by priming seeds in the presence of 3 μM ACC (75%) compared to stratified seeds (62%), while nontreated seeds had the lowest emergence percentage of 26%. These results indicate that priming in the presence of ACC might be an alternative to lengthy stratification treatments to break the dormancy and improve the germination and emergence of narrow-leafed purple coneflower seeds. [ABSTRACT FROM AUTHOR]

The aim of the present study was to evaluate the possible protective effects of Nigella sativaL. (NS) against ß-cell damage from streptozotocin (STZ)-induced diabetes in rats. STZ was injected intraperitoneally at a single dose of 50 mg/kg to induce diabetes. NS (0.2 ml/kg/day, i.p.) was injected for 3 days prior to STZ administration, and these injections were continued throughout the 4-week study. Oxidative stress is believed to play a role in the pathogenesis of diabetes mellitus (DM). To assess changes in the cellular antioxidant defense system, we measured the activities of antioxidant enzymes (such as glutathione peroxidase (GSHPx), superoxide dismutase (SOD), and catalase (CAT)) in pancreatic homogenates. We also measured serum nitric oxide (NO) and erythrocyte and pancreatic tissue malondialdehyde (MDA) levels, a marker of lipid peroxidation, to determine whether there is an imbalance between oxidant and antioxidant status. Pancreatic ß-cells were examined by immunohistochemical methods. STZ induced a significant increase in lipid peroxidation and serum NO concentrations, and decreased antioxidant enzyme activity. NS treatment has been shown to provide a protective effect by decreasing lipid peroxidation and serum NO, and increasing antioxidant enzyme activity. Islet cell degeneration and weak insulin immunohistochemical staining was observed in rats with STZ-induced diabetes. Increased intensity of staining for insulin, and preservation of ß-cell numbers were apparent in the NS-treated diabetic rats. These findings suggest that NS treatment exerts a therapeutic protective effect in diabetes by decreasing oxidative stress and preserving pancreatic ß-cell integrity. Consequently, NS may be clinically useful for protecting ß-cells against oxidative stress. © 2004 Wiley-Liss, Inc.

Despite the new diagnostic and therapeutic advancements, acute pancreatitis has still high rate of morbidity and mortality. We aimed to evaluate the effects of hyperbaric oxygen (HBO) therapy alone or combined with S-methylisothiourea (SMT), and meropenem (MER) therapy in an experimental rat model of acute necrotizing pancreatitis. Rats were randomly divided into 8 groups, and acute pancreatitis was induced in all groups except group 1. Treatment protocols were saline for group 2, SMT for group 3, SMT MER for group 4, SMT HBO for group 5, HBO for group 6, HBO MER for group 7, and MER for group 8. All surviving animals were killed 48 hours after the induction of pancreatitis, and specimens were collected. Oxidative stress parameters, histopathologic scores and amylase levels were better in treatment groups than in the positive control group (group 2). The most favorable results were obtained in HBO treatment groups, especially in HBO MER group (group 7). Our results indicate that adding HBO therapy to the antibiotic therapy will decrease oxidative stress parameters, serum amylase levels, and histopathological score. We suggest that adding the HBO therapy as an adjunctive to the treatment protocol of acute necrotizing pancreatitis may yield improvement in the morbidity and mortality of the disease.

We evaluated the relationship between nitric oxide and hyperbaric oxygenation in the pathogenesis and treatment of cyclophosphamide induced hemorrhagic cystitis in rats.

Shrimp biosolids (SB) are composed of shrimp fecal matter and decomposed shrimp feed and remain as debris in the bottoms of drained ponds used to culture shrimp. These biosolids are considered waste and usually disposed of in landfills. SB is a valuable source of N, P, K and a variety of other useful plants nutrients; however, SB contains high levels of Na. Field research was conducted to evaluate the potential of SB as a fertilizer source used with and without an inorganic fertilizer source (Osmocote 14N - 6P - 12K) to grow broccoli (Brassica oleracea italica). Yield of marketable heads/ha varied with SB/Osmocote (OSM) ratios. OSM at 75 kg/ha in combination with 9.0 MT SB/ha increased heads/ha significantly compared to lesser rates of each fertilizer source. This SB/OSM fertilizer regime contained a total of 263N - 116P - 99K - 99Na/ha. The biological yield increased 13% with OSM at 150 kg/ha and SB at 9.0 MT/ha, but if OSM was increased to 300 kg/ha, yield decreased significantly by 21% probably due to excessive fertilizer salts from both sources restricting plant growth. Lettuce field bioassays after broccoli production did not indicate that either fertilizer source persisted in the soil. The sodium in SB needs to be considered carefully whenever this material is used and SB should be evaluated in experimental trials before commercial use on other crops.

Hyperbaric oxygen therapy and mesna have been successfully used for hemorrhagic cystitis. We defined the protective effects of hyperbaric oxygen and mesna in further cyclophosphamide induced hemorrhagic cystitis in guinea pigs.

Shrimp biosolids (SB) have value as a fertilizer for bell pepper production, but maximum yields cannot be expected when SB is used alone. Although bell pepper marketable yield increased linearly with SB rate and also with Osmocote (OSM, a slow release encapsulated fertilizer) rate, yield at the highest OSM rate was 92% higher than yield at the highest SB rate. The cultural system that enhanced yield included both the highest rates of SB and OSM which delivered a combined total of 633 N - 253 P - 303 K kg/ha. The sodium in SB needs to be considered carefully whenever this material is used with plants. Apparently, SB persisted in the soil to benefit deeply-rooted crops months after initial application, but it is unknown if continued use of SB may eventually improve soil structure and physical properties.