Integrity and Quantity of Total Cell-Free DNA in the Diagnosis of Thyroid Cancer: Correlation with Cytological Classification.

Cell-free DNA (cfDNA) quantity and quality in plasma has been investigated as a non-invasive biomarker in cancer. Previous studies have demonstrated increased cfDNA amount and length in different types of cancer with respect to healthy controls. The present study aims to test the hypothesis that the presence of longer DNA strands circulating in plasma can be considered a biomarker for tumor presence in thyroid cancer. We adopted a quantitative real-time PCR (qPCR) approach based on the quantification of two amplicons of different length (67 and 180 bp respectively) to evaluate the integrity index 180/67. Cell-free DNA quantity and integrity were higher in patients affected by nodular thyroid diseases than in healthy controls. Importantly, cfDNA integrity index was higher in patients with cytological diagnosis of thyroid carcinoma (Thy4/Thy5) than in subjects with benign nodules (Thy2). Therefore, cfDNA integrity index 180/67 is a suitable parameter for monitoring cfDNA fragmentation in thyroid cancer patients and a promising circulating biomarker in the diagnosis of thyroid nodules.

Hyponatraemia alters the biophysical properties of neuronal cells independently of osmolarity: a study on Ni(2+) -sensitive current involvement.

What is the central question of this study? Hyponatraemia, an electrolyte disorder encountered in hospitalized patients, can cause neurological symptoms usually attributed to a reduction in plasma osmolarity. Here, we investigated whether low [Na(+) ] per se can cause neuronal changes independent of osmolarity, focusing on involvement of the Na(+) -Ca(2+) exchanger. What is the main finding and its importance? We show that hyponatraemia per se causes alterations of neuronal properties. The novel finding of Na(+) -Ca(2+) exchanger involvement helps us to elucidate the volume regulation following hyponatraemia. This might have relevance in a translational perspective because Na(+) -Ca(2+) exchanger could be a target for novel therapies. Hyponatraemia is the most frequent electrolyte disorder encountered in hospitalized patients, and it can cause a wide variety of neurological symptoms. Most of the negative effects of this condition on neuronal cells are attributed to cell swelling because of the reduction of plasma osmolarity, although in hyponatraemia different membrane proteins are supposed to be involved in the conservation of neuronal volume. We have recently reported detrimental effects of hyponatraemia on two different neuronal cell lines, SK-N-AS and SH-SY5Y, independent of osmotic alterations. In this study we investigated, in the same cell lines, whether hyponatraemic conditions per se can cause electrophysiological alterations and whether these effects vary over time. Accordingly, we carried out experiments in low-sodium medium in either hyposmotic [Osm(-)] or isosmotic [Osm(+)] conditions, for a short (24 h) or long time (7 days). Using a patch pipette in voltage-clamp conditions, we recorded possible modifications of cell capacitance (Cm ) and membrane conductance (Gm ). Our results indicate that in both Osm(-) and Osm(+) medium, Cm and Gm show a similar increase, but such effects are dependent on the time in culture in different ways. Notably, regarding the possible mechanisms involved in the maintenance of Cm , Gm and Gm /Cm in Osm(+) conditions, we observed a greater contribution of the Na(+) -Ca(2+) exchanger compared with Osm(-) and control conditions. Overall, these novel electrophysiological results help us to understand the mechanisms of volume regulation after ionic perturbation. Our results might also have relevance in a translational perspective because the Na(+) -Ca(2+) exchanger can be considered a target for planning novel therapies.

The Economic Burden of Hyponatremia: Systematic Review and Meta-Analysis.

BACKGROUND: Hyponatremia is the most common electrolyte abnormality observed in clinical practice. Several studies have demonstrated that hyponatremia is associated with an increased length of hospital stay and of hospital resource utilization. To clarify the impact of hyponatremia on the length of hospitalization and costs, we performed a meta-analysis based on published studies that compared hospital length of stay and cost between patients with and without hyponatremia. METHODS: An extensive Medline, Embase, and Cochrane search was performed to retrieve all studies published up to April 1, 2015 using the following words: "hyponatremia" or "hyponatraemia" AND "hospitalization" or "hospitalisation." A meta-analysis was performed including all studies comparing duration of hospitalization and hospital readmission rate in subjects with and without hyponatremia. RESULTS: Of 444 retrieved articles, 46 studies satisfied the inclusion criteria, encompassing a total of 3,940,042 patients; among these, 757,763 (19.2%) were hyponatremic. Across all studies, hyponatremia was associated with a significantly longer duration of hospitalization (3.30 [2.90-3.71; 95% CIs] mean days; P < .000). Similar results were obtained when patients with associated morbidities were analyzed separately. Furthermore, hyponatremic patients had a higher risk of readmission after the first hospitalization (odds ratio 1.32 [1.18-1.48; 95% CIs]; P < .000). A meta-regression analysis showed that the hyponatremia-related length of hospital stay was higher in males (Slope = 0.09 [0.05-0.12; 95% CIs]; P = .000 and Intercept = -1.36 [-3.03-0.32; 95% CIs]; P = .11) and in elderly patients (Slope = 0.002 [0.001-0.003; 95% CIs]; P < .000 and Intercept = 0.89 [0.83-0.97; 95% CIs]; P < .001). A negative association between serum [Na(+)] cutoff and duration of hospitalization was detected. No association between duration of hospitalization, serum [Na(+)], and associated morbidities was observed. Finally, when only US studies (n = 8) were considered, hyponatremia was associated with up to around $3000 higher hospital costs/patient when compared with the cost of normonatremic subjects. CONCLUSIONS: This meta-analysis confirms that hyponatremia is associated with a prolonged hospital length of stay and higher risk of readmission. These observations suggest that hyponatremia may represent one important determinant of the hospitalization costs.

Hyponatremia improvement is associated with a reduced risk of mortality: evidence from a meta-analysis.

BACKGROUND: Hyponatremia is the most common electrolyte disorder and it is associated with increased morbidity and mortality. However, there is no clear demonstration that the improvement of serum sodium concentration ([Na(+)]) counteracts the increased risk of mortality associated with hyponatremia. Thus, we performed a meta-analysis that included the published studies that addressed the effect of hyponatremia improvement on mortality. METHODS AND FINDINGS: A Medline, Embase and Cochrane search was performed to retrieve all English-language studies of human subjects published up to June 30th 2014, using the following words: "hyponatremia", "hyponatraemia", "mortality", "morbidity" and "sodium". Fifteen studies satisfied inclusion criteria encompassing a total of 13,816 patients. The identification of relevant abstracts, the selection of studies and the subsequent data extraction were performed independently by two of the authors, and conflicts resolved by a third investigator. Across all fifteen studies, any improvement of hyponatremia was associated with a reduced risk of overall mortality (OR=0.57[0.40-0.81]). The association was even stronger when only those studies (n=8) reporting a threshold for serum [Na(+)] improvement to >130 mmol/L were considered (OR=0.51[0.31-0.86]). The reduced mortality rate persisted at follow-up (OR=0.55[0.36-0.84] at 12 months). Meta-regression analyses showed that the reduced mortality associated with hyponatremia improvement was more evident in older subjects and in those with lower serum [Na(+)] at enrollment. CONCLUSIONS: This meta-analysis documents for the first time that improvement in serum [Na(+)] in hyponatremic patients is associated with a reduction of overall mortality.

A case of osmotic demyelination syndrome occurred after the correction of severe hyponatraemia in hyperemesis gravidarum.

BACKGROUND: Osmotic demyelination syndrome (ODS) may be observed as a result of a rapid change in serum osmolarity, such as that induced by an overly rapid correction of serum sodium levels in hyponatraemic patients. CASE PRESENTATION: We describe the case of a 21-year-old woman who was hospitalized at week 10 of gestation because of severe hyperemesis. At admission the patient appeared restless and confused and severe hyponatraemia (serum sodium 107 mmol/L) and hypokalemia (serum potassium 1.1 mmol/L) were detected. Active and simultaneous correction of these imbalances led to an overly rapid increase of serum sodium levels (17 mmol/L in the first 24 hours). Isotonic saline solution was stopped and replaced by 5% dextrose solution infusion. However, the neurological alterations worsened and the radiological features were consistent with the diagnosis of extra-pontine ODS. Steroids were administered intravenously with progressive improvement of biochemical and clinical abnormalities. At the time of discharge, 20 days later, the patient was able to walk and eat autonomously with only minimal external support. CONCLUSIONS: This report illustrates an unusual case of ODS, occurred after an excessive rate of correction of hyponatraemia obtained with isotonic saline infusion. Hypokaliemia and its active correction very likely played a crucial role in facilitating the onset of ODS. This interesting aspect will be explained in detail in the article. A more cautious and thoughtful correction of electrolyte alterations, would have probably prevented the onset of ODS in this patient. Physicians should be aware of the possibly fatal consequences that an exceedingly rapid change of serum osmolarity may have and should strictly follow the known safety measures in order to prevent it to occur.

Effects of Hyponatremia on the Brain.

Hyponatremia is a very common electrolyte disorder, especially in the elderly, and is associated with significant morbidity, mortality and disability. In particular, the consequences of acute hyponatremia on the brain may be severe, including permanent disability and death. Also chronic hyponatremia can affect the health status, causing attention deficit, gait instability, increased risk of falls and fractures, and osteoporosis. Furthermore, an overly rapid correction of hyponatremia can be associated with irreversible brain damage, which may be the result of the osmotic demyelination syndrome. This review analyzes the detrimental consequences of acute and chronic hyponatremia and its inappropriate correction on the brain and the underlying physiopathological mechanisms, with a particular attention to the less known in vivo and in vitro effects of chronic hyponatremia.

Moderate hyponatremia is associated with increased risk of mortality: evidence from a meta-analysis.

BACKGROUND: Hyponatremia is the most common electrolyte disorder in clinical practice, and evidence to date indicates that severe hyponatremia is associated with increased morbidity and mortality. The aim of our study was to perform a meta-analysis that included the published studies that compared mortality rates in subjects with or without hyponatremia of any degree. METHODS AND FINDINGS: An extensive Medline, Embase and Cochrane search was performed to retrieve the studies published up to October 1st 2012, using the following words: "hyponatremia" and "mortality". Eighty-one studies satisfied inclusion criteria encompassing a total of 850222 patients, of whom 17.4% were hyponatremic. The identification of relevant abstracts, the selection of studies and the subsequent data extraction were performed independently by two of the authors, and conflicts resolved by a third investigator. Across all 81 studies, hyponatremia was significantly associated with an increased risk of overall mortality (RR = 2.60[2.31-2.93]). Hyponatremia was also associated with an increased risk of mortality in patients with myocardial infarction (RR = 2.83[2.23-3.58]), heart failure (RR = 2.47[2.09-2.92]), cirrhosis (RR = 3.34[1.91-5.83]), pulmonary infections (RR = 2.49[1.44-4.30]), mixed diseases (RR = 2.59[1.97-3.40]), and in hospitalized patients (RR = 2.48[2.09-2.95]). A mean difference of serum [Na(+)] of 4.8 mmol/L was found in subjects who died compared to survivors (130.1 ± 5.6 vs 134.9 ± 5.1 mmol/L). A meta-regression analysis showed that the hyponatremia-related risk of overall mortality was inversely correlated with serum [Na(+)]. This association was confirmed in a multiple regression model after adjusting for age, gender, and diabetes mellitus as an associated morbidity. CONCLUSIONS: This meta-analysis shows for the first time that even a moderate serum [Na(+)] decrease is associated with an increased risk of mortality in commonly observed clinical conditions across large numbers of patients.

Exendin-4 induces cell adhesion and differentiation and counteracts the invasive potential of human neuroblastoma cells.

Exendin-4 is a molecule currently used, in its synthetic form exenatide, for the treatment of type 2 diabetes mellitus. Exendin-4 binds and activates the Glucagon-Like Peptide-1 Receptor (GLP-1R), thus inducing insulin release. More recently, additional biological properties have been associated to molecules that belong to the GLP-1 family. For instance, Peptide YY and Vasoactive Intestinal Peptide have been found to affect cell adhesion and migration and our previous data have shown a considerable actin cytoskeleton rearrangement after exendin-4 treatment. However, no data are currently available on the effects of exendin-4 on tumor cell motility. The aim of this study was to investigate the effects of this molecule on cell adhesion, differentiation and migration in two neuroblastoma cell lines, SH-SY5Y and SK-N-AS. We first demonstrated, by Extra Cellular Matrix cell adhesion arrays, that exendin-4 increased cell adhesion, in particular on a vitronectin substrate. Subsequently, we found that this molecule induced a more differentiated phenotype, as assessed by i) the evaluation of neurite-like protrusions in 3D cell cultures, ii) the analysis of the expression of neuronal markers and iii) electrophysiological studies. Furthermore, we demonstrated that exendin-4 reduced cell migration and counteracted anchorage-independent growth in neuroblastoma cells. Overall, these data indicate for the first time that exendin-4 may have anti-tumoral properties.

Low extracellular sodium causes neuronal distress independently of reduced osmolality in an experimental model of chronic hyponatremia.

There is evidence that chronic hyponatremia, even when mild, may cause neurological signs and symptoms. These have been traditionally associated with water movement into nervous cells, as a result of the hypotonic state. The aim of the present study was to determine whether low extracellular sodium directly exerts negative effects on human neuronal cells, independently of reduced osmolality. We exposed neuroblastoma SK-N-AS and SH-SY5Y cells to sustained low extracellular sodium, thus mimicking a condition of chronic hyponatremia, both in the presence of reduced and in the presence of unaltered osmolality. We found that very low sodium (i.e., 115 mmol/L in SK-N-AS and 90 mmol/L in SH-SY5Y) significantly reduced cell viability. However, intermediate low sodium was able to cause cell distress, as assessed by the altered expression of anti-apoptotic genes and the reduced ability to differentiate into a mature neuronal phenotype. Noteworthy, these effects were observed also in the presence of unaltered osmolality. Moreover, we performed a comprehensive microarray analysis in cells maintained in normal sodium or in low sodium and unaltered osmolality, and we found that the most altered pathway included genes involved in "cell death and survival." Among the more than 40 differentially expressed genes, the Heme oxygenase gene, which represents a transcriptional response to oxidative stress, showed the highest increase in the expression level. This study demonstrates that low extracellular sodium causes detrimental effects in neuronal cells that are at least in part independent of reduced osmolality. These findings further support the recommendation to effectively correct hyponatremia, even when mild and chronic.