314 resultados para HEMODYNAMIC-CHANGES
Resumo:
The hydrogen isotope ratio (HIR) of body water and, therefore, of all endogenously synthesized compounds in humans, is mainly affected by the HIR of ingested drinking water. As a consequence, the entire organism and all of its synthesized substrates will reflect alterations in the isotope ratio of drinking water, which depends on the duration of exposure. To investigate the effect of this change on endogenous urinary steroids relevant to doping-control analysis the hydrogen isotope composition of potable water was suddenly enriched from -50 to 200 0/00 and maintained at this level for two weeks for two individuals. The steroids under investigation were 5β-pregnane-3α,20α-diol, 5α-androst-16-en-3α-ol, 3α-hydroxy-5α-androstan-17-one (ANDRO), 3α-hydroxy-5β-androstan-17-one (ETIO), 5α-androstane-3α,17β-diol, and 5β-androstane-3α,17β-diol (excreted as glucuronides) and ETIO, ANDRO and 3β-hydroxyandrost-5-en-17-one (excreted as sulfates). The HIR of body water was estimated by determination of the HIR of total native urine, to trace the induced changes. The hydrogen in steroids is partly derived from the total amount of body water and cholesterol-enrichment could be calculated by use of these data. Although the sum of changes in the isotopic composition of body water was 150 0/00, shifts of approximately 30 0/00 were observed for urinary steroids. Parallel enrichment in their HIR was observed for most of the steroids, and none of the differences between the HIR of individual steroids was elevated beyond recently established thresholds. This finding is important to sports drug testing because it supports the intended use of this novel and complementary methodology even in cases where athletes have drunk water of different HIR, a plausible and, presumably, inevitable scenario while traveling.
Resumo:
Introduction: Rotenone is a botanical pesticide derived from extracts of Derris roots, which is traditionally used as piscicide, but also as an industrial insecticide for home gardens. Its mechanism of action is potent inhibition of mitochondrial respiratory chain by uncoupling oxidative phosphorylation by blocking electron transport at complex-I. Despite its classification as mild to moderately toxic to humans (estimated LD50, 300-500 mg/kg), there is a striking variety of acute toxicity of rotenone depending on the formulation (solvents). Human fatalities with rotenone-containing insecticides have been rarely reported, and a rapid deterioration within a few hours of the ingestion has been described previously in one case. Case report: A 49-year-old Tamil man with a history of asthma, ingested 250 mL of an insecticide containing 1.24% of rotenone (3.125 g, 52.1-62.5 mg/kg) in a suicide attempt at home. The product was not labeled as toxic. One hour later, he vomited repeatedly and emergency services were alerted. He was found unconscious with irregular respiration and was intubated. On arrival at the emergency department, he was comatose (GCS 3) with fixed and dilated pupils, and absent corneal reflexes. Physical examination revealed hemodynamic instability with hypotension (55/30 mmHg) and bradycardia (52 bpm). Significant laboratory findings were lactic acidosis (pH 6.97, lactate 17 mmol/L) and hypokalemia (2 mmol/L). Cranial computed tomography (CT) showed early cerebral edema. A single dose of activated charcoal was given. Intravenous hydration, ephedrine, repeated boli of dobutamine, and a perfusor with 90 micrograms/h norepinephine stabilized blood pressure temporarily. Atropine had a minimal effect on heart rate (58 bpm). Intravenous lipid emulsion was considered (log Pow 4.1), but there was a rapid deterioration with refractory hypotension and acute circulatory failure. The patient died 5h after ingestion of the insecticide. No autopsy was performed. Quantitative analysis of serum performed by high-resolution/accurate mass-mass spectrometry and liquid chromatography (LC-HR/AM-MS): 560 ng/mL rotenone. Other substances were excluded by gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-mass spectrometry (LC-MS/MS). Conclusion: The clinical course was characterized by early severe symptoms and a rapidly fatal evolution, compatible with inhibition of mitochondrial energy supply. Although rotenone is classified as mild to moderately toxic, physicians must be aware that suicidal ingestion of emulsified concentrates may be rapidly fatal. (n=3): stridor, cyanosis, cough (one each). Local swelling after chewing or swallowing soap developed at the earliest after 20 minutes and persisted beyond 24 hours in some cases. Treatment with antihistamines and/or steroids relieved the symptoms in 9 cases. Conclusion: Bar soap ingestion by seniors carries a risk of severe local reactions. Half the patients developed symptoms, predominantly swellings of tongue and/or lips (38%). Cognitive impairment, particularly in the cases of dementia (37%), may increase the risk of unintentional ingestion. Chewing and intraoral retention of soap leads to prolonged contact with the mucosal membranes. Age-associated physiological changes of oral mucosa probably promote the irritant effects of the surfactants. Medical treatment with antihistamines and corticosteroids usually leads to rapid decline of symptoms. Without treatment, there may be a risk of airway obstruction.
Resumo:
We recently reported on the deficiency of carbohydrate sulfotransferase 3 (CHST3; chondroitin-6-sulfotransferase) in six subjects diagnosed with recessive Larsen syndrome or humero-spinal dysostosis [Hermanns et al. (2008); Am J Hum Genet 82:1368-1374]. Since then, we have identified 17 additional families with CHST3 mutations and we report here on a series of 24 patients in 23 families. The diagnostic hypothesis prior to molecular analysis had been: Larsen syndrome (15 families), humero-spinal dysostosis (four cases), chondrodysplasia with multiple dislocations (CDMD "Megarbane type"; two cases), Desbuquois syndrome (one case), and spondylo-epiphyseal dysplasia (one case). In spite of the different diagnostic labels, the clinical features in these patients were similar and included dislocation of the knees and/or hips at birth, clubfoot, elbow joint dysplasia with subluxation and limited extension, short stature, and progressive kyphosis developing in late childhood. The most useful radiographic clues were the changes of the lumbar vertebrae. Twenty-four different CHST3 mutations were identified; 16 patients had homozygous mutations. We conclude that CHST3 deficiency presents at birth with congenital dislocations of knees, hips, and elbows, and is often diagnosed initially as Larsen syndrome, humero-spinal dysostosis, or chondrodysplasia with dislocations. The incidence of CHST3 deficiency seems to be higher than assumed so far. The clinical and radiographic pattern (joint dislocations, vertebral changes, normal carpal age, lack of facial flattening, and recessive inheritance) is characteristic and distinguishes CHST3 deficiency from other disorders with congenital dislocations such as filamin B-associated dominant Larsen syndrome and Desbuquois syndrome.
Resumo:
We have investigated the changes in the responses to noradrenaline of isolated tail arteries of spontaneously hypertensive (SHR) and renovascular hypertensive rats (Wistar-Kyoto: two-kidney, one-clip model, WKY:2K1C) compared with normotensive (Wistar-Kyoto, WKY) rats. Renovascular hypertension was induced by 4 weeks' unilateral renal artery clipping. Arteries were vasoconstricted with exogenous noradrenaline, electrical field stimulation or high potassium. The effects of the latter two stimuli were abolished by reserpine and so were presumably dependent on the presence of endogenous noradrenaline. In the SHR the maximal vasoconstriction produced by all three stimuli was greater than in WKY. Dose-response curves were steeper and there was no change in threshold. Vascular mass was greater. We interpret these results as showing an increase in vascular reactivity in the SHR caused by structural adaptation. The WKY:2K1C responses to noradrenaline could also be explained in terms of structural adaptation but there was no increase in vascular mass. Sensitivity to potassium and electrical stimulation was decreased, suggesting a defect in vascular neurotransmission. This was supported by the observations of a decreased arterial noradrenaline content and of decreased sensitivity to cocaine.
Resumo:
Summary For the nutritional management of bone health and the prevention of osteoporosis it is important to identify nutrients that positively influence the bone remodeling process at the cellular level. Soy isoflavones show promising osteoprotective effects in animals and humans but their mechanism of action in bone cells is yet poorly understood. Firstly, soy tissue cultures were characterized as a new and optimized source of isoflavones. A large variability in the isoflavone content was observed and high-producing strains (46.3 mg/g dry wt isoflavones) were identified. In the Ishikawa cells bioassay, the estrogenicity of isoflavones was confirmed to be 1000 to 10000 less than 17Mestradiol and that of the malonyl forms was shown for the first time (EC50 of 350 nM and 1880 nM for malonylgenistin and malonyldaidzin, respectively). The estrogenic activity of soya tissue culture extracts correlated to their isoflavone content. Secondly, the effects of phytonutrients on BMP-2 gene expression and on the mevalonate synthesis pathway, as key mediators of bone formation, were investigated. Dietary achievable concentrations of genistein and daidzein (10vM), and statins (4xM) but not 17M estradiol (10nM), induced BMP-2 gene expression (by up to 3-fold) and inhibited the cholesterol biosynthetic pathway (by up to 50%) in the human osteoblastic cell line hP0B¬tert. In addition, several plant extracts (Cyperus rotundus, Lindera benzoin and Cnidium monnieri) induced BMP-2 gene expression but this induction was not restricted to the inhibition of the cholesterol synthesis pathway neither to the estrogenicity. Finally, the gene expression profiles during hP0B-tert differentiation induced by vitamin D and dexamethasone were analyzed with the Affymetrix human GeneChip. 1665 different genes and 98 ESTs were significantly regulated. The expression profiles of bone-related genes was largely in agreement with previously documented patterns, supporting the physiological relevance of the genomic results and the hP0B-tert cell line as a valid model of human osteoblast differentiation. The expression of alternative differentiation markers during the osteogenic treatment of hP0B-tert cells indicated that the adipocyte and myoblast differentiation pathways were repressed, confirming that these culture conditions allowed only osteoblast differentiation. The gene ontology analysis identified further sub-groups of genes that may be involved in the bone formation process. Aims of the thesis In order to define new strategies for the nutritional management of bone health and for the prevention of osteoporosis the major goal of the present work was to investigate the potential of phytonutrients to positively modulate the bone formation process at the cellular level and, in particular: 1.To select and optimise alternative plant sources containing high levels of isoflavones with estrogenic activity (Chapter 3). 2.To compare the effects of statins and phytonutrients on BMP-2 gene expression and on the mevalonate synthesis pathway and to select new plant extracts with a bone anabolic potential (Chapter 4). 3.To further characterize the new human periosteal cell line, hP0B-tert, as a bone- formation model, by elucidating its gene expression profile during differentiation induced by vitamin D and dexamethasone (Chapter 5).
Resumo:
The genetics and pathogenesis of splenic marginal zone lymphoma are poorly understood. The lymphoma lacks chromosome translocation, and ~30% of cases are featured by 7q deletion, but the gene targeted by the deletion is unknown. A recent study showed inactivation of A20, a 'global' NF-kB negative regulator, in 1 of 12 splenic marginal zone lymphoma. To investigate further whether deregulation of the NF-kB pathway plays a role in the pathogenesis of splenic marginal zone lymphoma, we screened several NF-kB regulators for genetic changes by PCR and sequencing. Somatic mutations were found in A20 (6/46=13%), MYD88 (6/46=13%), CARD11 (3/34=8.8%), but not in CD79A, CD79B and ABIN1. Interestingly, these genetic changes are largely mutually exclusive from each other and MYD88 mutation was also mutually exclusive from 7q deletion. These results strongly suggest that deregulation of the TLR (toll like receptor) and BCR (B-cell receptor) signalling pathway may play an important role in the pathogenesis of splenic marginal zone lymphoma.
Resumo:
INTRODUCTION: Pulmonary hypertension is a hemodynamic condition occurring rarely in pediatrics. Nevertheless, it is associated with significant morbidity and mortality. When characterized by progressive pulmonary vascular structural changes, the disease is called pulmonary arterial hypertension (PAH). It results in increased pulmonary vascular resistance and eventual right ventricular failure. In the vast majority of cases, pediatric PAH is idiopathic or associated with congenital heart disease, and, contrary to adult PAH, is rarely associated with connective tissue, portal hypertension, HIV infection or thromboembolic disease. AREAS COVERED: This article reviews the current drug therapies available for the management of pediatric PAH. These treatments target the recognized pathophysiological pathways of PAH with endothelin-1 receptor antagonists, prostacyclin analogs and PDE type 5 inhibitors. New treatments and explored pathways are briefly discussed. EXPERT OPINION: Although there is still no cure for PAH, quality of life and survival have been improved significantly with specific drug therapies. Nevertheless, management of pediatric PAH remains challenging, and depends mainly on results from adult clinical trials and pediatric experts. Further research on PAH-specific treatments in the pediatric population and data from international registries are needed to identify optimal therapeutic strategies and treatment goals in the pediatric population.
Resumo:
Adjuvants have been shown since many years to have an important role in enhancing the immune responses against the co-administered antigens used as vaccines. The continuous study of the mechanism of action of adjuvants is necessary to develop further safe and efficacious vaccines. Complete Freund's adjuvant (CFA) is currently in use as adjuvant to induce some autoimmune diseases in murine models, therefore the study of the mechanisms involved in the generation of the related immune responses could be instrumental for the understanding of the induction of inflammatory Thl7 responses. In the present work, we showed in C57B1/6 mice that CFA peripheral administration induces very early, at 6 h, a potent influx of CDllb+ cells, mainly neutrophils (CD11b+Ly6GhighLy6Cint) and monocytes (CD11b+Ly6GlowLy6Chigh), in the draining lymph node. By investigating the route by which neutrophils reach the lymph node we observed that, around 20% of them arrive from the afferent lymph and the majority stains positive for Mycobacterium tuberculosis. We also observed a correlation between the influx of neutrophils and an increase in IL-23 and IL-Ιβ, together with several inflammatory chemokines, in the draining lymph node. Concomitantly, we detected the expression of the IL-23 receptor on CDllc+ DCs. Moreover, we confirmed the ability of murine neutrophils to express IL-23 both, in vitro by stimulating bone-marrow extracted PMNs with Mycobacterium tuberculosis, and on total cells from draining lymph node by immunohistochemistry. We also observed by in vivo priming a reduction in the percentage of IFN-γ and CXCR3 expressing Τ cells upon depletion of neutrophils. Altogether, we show that upon stimulation from the periphery, the draining lymph node undergo changes in cytokine/chemokine production leading to the recruitment of different leukocytes subpopulations. Here we show that CFA induces a rapid influx of neutrophils which are responsible for the production of IL-23 that in turn influences the generation of Τ helper cells.
Resumo:
STUDY OBJECTIVES: Gamma-hydroxybutyrate (GHB) was originally introduced as an anesthetic but was first abused by bodybuilders and then became a recreational or club drug.1 Sodium salt of GHB is currently used for the treatment of cataplexy in patients with narcolepsy. The mode of action and metabolism of GHB is not well understood. GHB stimulates growth hormone release in humans and induces weight loss in treated patients, suggesting an unexplored metabolic effect. In different experiments the effect of GHB administration on central (cerebral cortex) and peripheral (liver) biochemical processes involved in the metabolism of the drug, as well as the effects of the drug on metabolism, were evaluated in mice. DESIGN: C57BL/6J, gamma-aminobutyric acid B (GABAB) knockout and obese (ob/ob) mice were acutely or chronically treated with GHB at 300 mg/kg. MEASUREMENTS AND RESULTS: Respiratory ratio decreased under GHB treatment, independent of food intake, suggesting a shift in energy substrate from carbohydrates to lipids. GHB-treated C57BL/6J and GABAB null mice but not ob/ob mice gained less weight than matched controls. GHB dramatically increased the corticosterone level but did not affect growth hormone or prolactin. Metabolome profiling showed that an acute high dose of GHB did not increase the brain GABA level. In the brain and the liver, GHB was metabolized into succinic semialdehyde by hydroxyacid-oxoacid transhydrogenase. Chronic administration decreased glutamate, s-adenosylhomocysteine, and oxidized gluthathione, and increased omega-3 fatty acids. CONCLUSIONS: Our findings indicate large central and peripheral metabolic changes induced by GHB with important relevance to its therapeutic use.