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Background

Mid-ventricular obstructive hypertrophic cardiomyopathy (MVOHC) is a rare type of cardiomyopathy. The diagnosis is based on the hourglass appearance on the left ventriculogram and the presence of pressure gradient between apical and basal chamber of the ventriculum on the hemodynamic assessment.

Case presentation

The present case represents successful percutaneous treatment with septal ablation to patient with MVOHC associated with systolic anterior motion of the mitral valve and obstruction at both the mid-ventricular and outflow levels.

Conclusion

Alcohol septal ablation has been proposed as less invasive alternatives to surgery in patients with MVOHC.  相似文献   
54.
A study was conducted to evaluate the effect of two dietary carbohydrate sources (waxy maize starch and glucose) on the metabolic adaptation of sea bass juveniles (initial weight: 24 g) to a heat shock treatment (temperature rise from 18 degrees C to 25 degrees C within 24 h). Two isonitrogenous and isolipidic diets were formulated to contain 20% waxy maize starch (WS diet) or 20% glucose (GLU diet). Triplicate groups of fish were fed to near satiation for 4 weeks at both temperatures (18 degrees C and 25 degrees C). Then, fish previously maintained at 18 degrees C were submitted to a heat shock (18 degrees C to 25 degrees C) and continued to be fed with the same diets during 1 more week. The higher water temperature significantly improved growth performance, feed efficiency, as well as protein efficiency ratio, independently of diet. At 25 degrees C, but not at 18 degrees C, growth of fish fed the WS diet was higher than that of fish fed the GLU diet. Plasma glucose levels were higher in sea bass fed the GLU diet and not influenced by water temperature. Fish fed a glucose diet or reared at high temperatures (25 degrees C) showed enhanced liver glycolytic, lipogenic and gluconeogenic capacities compared to fish fed a starch diet or reared at low temperatures (18 degrees C). For the majority of the enzymes studied, 1 week seemed to be enough time for metabolic adaptation in sea bass submitted to an acute heat shock. Irrespective of carbohydrate source, HSP70 gene expression was similar in both cold water (18 degrees C) and warm water (25 degrees C) acclimated sea bass. A weak down regulation was observed after heat shock only in fish fed the GLU diet. This suggests that HSP70 gene expression is not affected by the rearing temperature per se.  相似文献   
55.
We studied whether taurine has any regressive effect on existing atherosclerotic lesions and lipid peroxidation in rabbits fed on a high-cholesterol (HC) diet. The cholesterol, triglyceride, malondialdehyde (MDA) and diene conjugate (DC) levels, as well as the aortic histopathological findings were examined in rabbits that had been fed on a cholesterol-containing diet for 8 months [0.5% cholesterol (w/w) for 3 months and subsequently 0.25% cholesterol (w/w) for 5 months], and then for a further 4 months on a normal diet with or without taurine treatment [1% (w/v) in the drinking water]. High levels of lipid and lipid peroxide induced by the HC diet were observed to decline in the plasma, liver and aorta of atherosclerotic rabbits, as well as a slight retardation in aortic atherosclerotic lesions during the regression period. Although no significant differences in the lipid and lipid peroxide levels in the plasma and aorta were found between the regressed groups with or without the taurine treatment, the extent of atherosclerotic lesions in the aorta was less in the taurine-treated regressed group than in the non-treated regressed group. However, the liver MDA and DC levels were lower in the regressed rabbits with the taurine treatment in the non-treated group. These results indicate that the taurine treatment may accelerate the regression of cholesterol-induced atherosclerotic lesions in rabbits without having any effect on the plasma and aorta lipid and lipid peroxide levels.  相似文献   
56.
Selenium (Se) has long been recognized as both an essential mammalian nutrient and a hazardous element. Sodium selenite is commonly used as a dietary supplement for the treatment of Se deficiency. On the other hand, chronic Se toxicity has been demonstrated to affect the major organs, including the heart, in experimental animals. This study examines the effects of high concentrations of extracellular selenite (in the range of 0.001–1 mM) application into the recording bath on the electrical properties of rat papillary muscles. Conventional glass semifloating microelectrodes were used to record intracellular action potentials (APs) in isolated rat papillary muscles. The amplitude of APs and the resting membrane potential of papillary muscles were not changed following a 20-min selenite (1 mM) application compared to the first minute of its application. Freshly isolated ventricular myocytes by an enzymatic method were used to determine the selenite-induced alterations in Na+ currents. Na+ currents, measured at 22°C, by the whole-cell patch-clamp technique, decreased by 38±8% in the presence of 1 mM selenite for 5 min. These selenite-induced effects were not reversed, but are restored by dithiothreitol (1 mM). These results demonstrated that toxic concentrations of selenite induced a significant shortening in AP duration as a result of an increase in the rate of repolarization. Our findings also suggest that a decrease in Na+ currents, in addition to Ca2+ currents, may play a role in the shortening of AP duration in rat papillary muscles.  相似文献   
57.
Microspore embryogenesis is the most commonly used method to produce doubled haploids. It is based on the ability of a single haploid cell, the microspore, to de-differentiate and regenerate into a whole plant after being exposed to stresses, such as low or high temperatures, carbon starvation and colchicine. Some stresses such as temperature treatments and carbon starvation have been used with success in many plant species, whereas others such as colchicine had limited application in a few species. Reports on the application of whole plant treatments with feminizing agents on inflorescences and buds are scarce. Furthermore, the technical means to apply some stresses such as γ-irradiation are not readily available. Recently, novel stresses such as pH, inducer chemicals, carrageenan oligosaccharides and heavy metals were reported to induce microspore embryogenesis. It remains to be seen, however, whether these stresses are effective in a wider range of species. Finally, pretreatment of cultured cells with high concentrations of 2,4-D efficiently induces somatic embryogenesis in several species (carrot, alfalfa). However, reports on the use of this particular chemical stress are not available in microspore embryogenesis. The paper presented here gives an overview of various stresses and mechanisms of action of these stresses in inducing microspore embryogenesis.  相似文献   
58.
Exopolysaccharides were isolated and purified from Lactobacillus johnsonii FI9785, which has previously been shown to act as a competitive exclusion agent to control Clostridium perfringens in poultry. Structural analysis by NMR spectroscopy revealed that L. johnsonii FI9785 can produce two types of exopolysaccharide: EPS-1 is a branched dextran with the unusual feature that every backbone residue is substituted with a 2-linked glucose unit, and EPS-2 was shown to have a repeating unit with the following structure: -6)-α-Glcp-(1–3)-β-Glcp-(1–5)-β-Galf-(1–6)-α-Glcp-(1–4)-β-Galp-(1–4)-β-Glcp-(1-. Sites on both polysaccharides were partially occupied by substituent groups: 1-phosphoglycerol and O-acetyl groups in EPS-1 and a single O-acetyl group in EPS-2. Analysis of a deletion mutant (ΔepsE) lacking the putative priming glycosyltransferase gene located within a predicted eps gene cluster revealed that the mutant could produce EPS-1 but not EPS-2, indicating that epsE is essential for the biosynthesis of EPS-2. Atomic force microscopy confirmed the localization of galactose residues on the exterior of wild type cells and their absence in the ΔepsE mutant. EPS2 was found to adopt a random coil structural conformation. Deletion of the entire 14-kb eps cluster resulted in an acapsular mutant phenotype that was not able to produce either EPS-2 or EPS-1. Alterations in the cell surface properties of the EPS-specific mutants were demonstrated by differences in binding of an anti-wild type L. johnsonii antibody. These findings provide insights into the biosynthesis and structures of novel exopolysaccharides produced by L. johnsonii FI9785, which are likely to play an important role in biofilm formation, protection against harsh environment of the gut, and colonization of the host.  相似文献   
59.
Tissues respond to injury with inflammation in an effort to protect and repair the damaged site. During inflammation, leukocytes typically accumulate in response to certain chemicals produced within the tissue itself. The passage of leukocytes through the vascular lumen into tissues occurs in several phases, including rolling, activation, firm adhesion, transendothelial migration, and subendothelial migration. Although infiltration of eosinophil leukocytes is one of the most important aspects of allergic inflammatory reactions, eosinophils also participate in nonallergic inflammation. Eosinophil accumulation is regulated not only by endothelial adhesion molecules, but also by interactions between eosinophil adhesion molecules and extracellular matrix elements. This review summarizes the regulation of eosinophil leukocyte adhesion and migration. A better understanding of eosinophil recruitment responses may lead to the development of novel therapeutics for chronic allergic diseases.  相似文献   
60.
In this study, histopathological and biochemical changes due to chronic usage of morphine or tramadol in liver and kidney were assessed in rats. Thirty male Wistar rats (180–220 g) were included and divided into three groups. Normal saline (1 ml) was given intraperitoneally as placebo in the control group (n = 10). Morphine group (n = 10) received morphine intraperitoneally at a dose of 4, 8, 10 mg/kg/day in the first, second and the third ten days of the study, respectively. Tramadol group (n = 10), received the drug intraperitoneally at doses of 20, 40 and 80 mg/kg/day in the first, second and the third ten days of the study, respectively. Aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH), creatinin, blood urea nitrogen (BUN) and malondialdehyde (MDA) levels were measured in the serum. Liver and kidney specimens were evaluated by light microscopy. Serum ALT, AST, LDH, BUN and creatinin levels were significantly higher in morphine group compared to the control group. Serum LDH, BUN and creatinin levels were significantly increased in the morphine group compared to the tramadol group. The mean MDA level was significantly higher in morphine group compared to the tramadol and control groups (P<0.05). Light microscopy revealed severe centrolobular congestion and focal necrosis in the liver of morphine and tramadol groups, but perivenular necrosis was present only in the morphine group. The main histopathologic finding was vacuolization in tubular cells in morphine and tramadol groups. Our findings pointed out the risk of increased lipid peroxidation, hepatic and renal damage due to long term use of opioids, especially morphine. Although opioids are reported to be effective in pain management, their toxic effects should be kept in mind during chronic usage Presented at the 10th XX Annual ESRA Congress, 6–9 April 2002, Warsaw, Poland.  相似文献   
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