Search results for "Acidosi"

Effect of acidosis on lipid peroxidation in brain slices.

1991

Acidification of the incubation medium markedly increased lipid peroxidation of cortical brain slices. Lactic acidosis caused a more extensive lipid peroxidation than did phosphoric acidosis (+35% at pH 6 and +81% at pH 5), probably due to the rapid diffusion of the protonated form of lactic acid across cell membranes. These results support the hypothesis that free radical mechanisms may be involved in the cytotoxicity of acidosis.

Remission phase in children diagnosed with type 1 diabetes in years 2012 to 2013 in Silesia, Poland: An observational study

2018

Background/objective The study aimed to analyze the frequency of partial remission (PR) and its association with chosen clinical and laboratory factors among pediatric patients with newly diagnosed type 1 diabetes (T1D). The long-term effect of PR on chosen parameters was also investigated. Methods In 194 patients (95 girls) aged 8.1 ± 4.3 years, we analyzed data at T1D onset: glycemia, pH, C-peptide, antibodies, weight, and concomitant autoimmune diseases. Anthropometric parameters, daily insulin requirement (DIR), and HbA1c 2 and 4 years after T1D diagnosis were also analyzed. We determined PR based on HbA1c and DIR measurements at least every 3 months. Results PR occurred in 59% of patie…

Mitochondrial myopathy with lactic acidosis and deficient activity of muscle succinate cytochrome-c-oxidoreductase

1984

A male infant had severe muscular hypotonia from birth. Recurrent vomiting with dehydration and severe metabolic acidosis complicated the course. Elevated lactate (up to 12.3 mmol/l; n less than 2), pyruvate (0.4 mmol/l; n less than 0.05) and alanine levels were found in serum with an abnormal lactate/pyruvate ratio (greater than 30; n less than 15). In urine the concentrations of lactate, pyruvate, alanine and of several intermediates of the citric acid cycle were increased. In muscle, numerous disseminated "ragged red fibres" were found by light microscopy; muscle fibres were found to contain subsarcolemmal aggregates of mitochondria, lipid droplets and glycogen by electromicroscopical me…

Exercise hyperventilation in chronic heart failure is not caused by systemic lactic acidosis

2005

Background: Patients with heart failure have an abnormally high ventilatory response to exercise associated with gas exchange defects and reduced arterial pCO2. Aims: We examined the possibility of lactic acidosis as the stimulus to this increased ventilation that abnormally depresses pCO2 during exercise in heart failure. Method and results: We studied 18 patients with chronic heart failure. We measured VE/VCO2 slope during exercise, arterial blood gases and lactate concentrations during cardiopulmonary exercise testing (rest, peak exercise and one minute after the end of exercise). Neither VE/VCO2 slope nor arterial pCO2 were related to arterial lactate concentrations at peak exercise (r=…

C1-ESTERASE INHIBITOR REVERSES FUNCTIONAL CONSEQUENCES OF SUPERIOR MESENTERIC ARTERY ISCHEMIA/REPERFUSION BY LIMITING REPERFUSION INJURY AND RESTORIN…

2006

Activated complement contributes significantly to reperfusion injury after ischemia. This study explores functional consequences of C1-esterase inhibitor (C1-INH) treatment after superior mesenteric artery occlusion (SMAO)/ reperfusion using intravital microscopy. Thirty anesthetized, spontaneously breathing, male Sprague-Dawley rats underwent SMAO for 60 min followed by reperfusion (4 h). C1-esterase inhibitor (100 and 200 IU/kg body weight) or saline (0.9%) was given as a single bolus before reperfusion. Sham-operated animals (n = 10) without SMAO served as controls.Systemichemodynamicsweremonitoredcontinuously,arterial bloodgasesanalyzedintermittently, andleukocyte/ endothelial interacti…

Endocytotic uptake of HPMA-based polymers by different cancer cells: impact of extracellular acidosis and hypoxia.

2017

Daniel Gündel,1 Mareli Allmeroth,2 Sarah Reime,1 Rudolf Zentel,2 Oliver Thews1 1Institute of Physiology, Martin Luther University Halle-Wittenberg, Halle (Saale), 2Institute of Organic Chemistry, Johannes Gutenberg-University, Mainz, Germany Background: Polymeric nanoparticles allow to selectively transport chemotherapeutic drugs to the tumor tissue. These nanocarriers have to be taken up into the cells to release the drug. In addition, tumors often show pathological metabolic characteristics (hypoxia and acidosis) which might affect the polymer endocytosis.Materials and methods: Six different N-(2-hydroxypropyl)methacrylamide (HPMA)-based polymer structures (homopolymer as well as…

The effect of the type of colloid on the efficacy of hypertonic saline colloid mixtures in hemorrhagic shock: dextran versus hydroxyethyl starch

1993

Colloids increase and prolong the efficacy of hypertonic saline solutions in hemorrhagic shock. We compared the efficacy of dextran 60 and hydroxyethyl starch (HES) 200,000/0.5 at iso-oncotic concentrations of 6.5 or 6% in a 7.5% NaCI solution. Thirty-two rabbits were bled to maintain a mean arterial pressure at 35 mmHg. Twenty-five percent of the shed blood volume was replaced after 40 min by bolus infusion either with hypertonic dextran (HS-DEX) (n = 16) or with hypertonic hydroxyethyl starch (HS-HES) (n = 16). The animals were then observed for a 120-min period. In both groups immediate and complete restoration of cardiovascular function was achieved in up to 30 min and adequate restorat…

Impact of exogenous lactate on survival and radioresponse of carcinoma cells in vitro

2009

Tumour lactate levels have been shown to correlate with high radioresistance in tumour models in vivo. The study aimed to evaluate the impact of pathophysiological extracellular lactate concentrations and acidosis on the in vitro survival and radioresponse of various cancer cell lines.HCT-116, HT29 (colorectal) and FaDu (HNSCC) carcinoma cells were studied. Lactate release rates were determined, and expression of the monocarboxylate transporter MCT1 and its cofactor CD147 were monitored by immunofluorescence and flow cytometry. Colony formation was compared for cells exposed to 20 mM exogenous lactate, acidosis (pH 6.4) and lactate plus acidosis relative to control and dose response curves …

2013

Rodents are most useful models to study physiological and pathophysiological processes in early development, because they are born in a relatively immature state. However, only few techniques are available to monitor non-invasively heart frequency and respiratory rate in neonatal rodents without restraining or hindering access to the animal. Here we describe experimental procedures that allow monitoring of heart frequency by electrocardiography (ECG) and breathing rate with a piezoelectric transducer (PZT) element without hindering access to the animal. These techniques can be easily installed and are used in the present study in unrestrained awake and anesthetized neonatal C57/Bl6 mice and…

Interstitielle Nephritis bei atypischer Manifestation eines Sj�gren's Syndrom

1980

A patient was observed with interstitial nephritis which resulted in renal tubular acidosis (distal type), tubular proteinuria and defective urinary concentrating ability in the absence of edema, elevated arterial blood pressure, glomerular proteinuria or abnormal urinary sediment. The presence of interstitial nephritis was established by renal biopsy which showed dense infiltrates in the interstitium, interstitial fibrosis and thickening and splitting of the pericapillary basal membranes. Immunofluorescence was non contributory. Extrarenal symptoms were discrete (arthralgia of both hands, Raynaud's syndrome upon cold exposure). Mixed connective tissue disease (MCTD) was suspected because o…