Systematic review and meta-analysis on coronary calcifications in COVID-19.

Chest CT is valuable to detect alternative diagnoses/complications of COVID-19, while its role for prognostication requires further investigation. Non-pulmonary radiological findings such as cardiovascular calcifications could increase the predictivity of clinical outcomes of COVID-19 patients beyond pulmonary involvement. Several observational studies have reported mixed results on the role of coronary calcifications in COVID-19 patients as a predictor of hospitalization, ventilatory support, and mortality. The purpose of the study is to systematically review the available evidence on the predictive role of cardiovascular calcifications in SARS-CoV2 disease. The meta-analysis confirms the prognostic significance of coronary calcifications on hospital mortality, and coronary calcifications (CAC ≠ 0) were associated with an OR for mortality of 2.19 (95% CI 1.36-3.52). CAC was neutral on respiratory outcomes, but it was associated with an increased trend of cardiovascular events. Coronary calcium appears as a promising biomarker imaging even in short-term outcomes (MACEs, hospital mortality) in a non-cardiovascular disease such as Sars-CoV2 infection. Further large studies are needed to confirm promising results of this imaging biomarker in non-cardiovascular disease.

Faulty neuronal determination and cell polarization are reverted by modulating HD early phenotypes.

Increasing evidence suggests that early neurodevelopmental defects in Huntington's disease (HD) patients could contribute to the later adult neurodegenerative phenotype. Here, by using HD-derived induced pluripotent stem cell lines, we report that early telencephalic induction and late neural identity are affected in cortical and striatal populations. We show that a large CAG expansion causes complete failure of the neuro-ectodermal acquisition, while cells carrying shorter CAGs repeats show gross abnormalities in neural rosette formation as well as disrupted cytoarchitecture in cortical organoids. Gene-expression analysis showed that control organoid overlapped with mature human fetal cortical areas, while HD organoids correlated with the immature ventricular zone/subventricular zone. We also report that defects in neuroectoderm and rosette formation could be rescued by molecular and pharmacological approaches leading to a recovery of striatal identity. These results show that mutant huntingtin precludes normal neuronal fate acquisition and highlights a possible connection between mutant huntingtin and abnormal neural development in HD.

Organic fertilization leads to increased peach root production and lifespan.

We evaluated the effects of mineral and organic fertilizers on peach root dynamics in the growing season from 2003 to 2006 in a nectarine (Prunus persica L.) orchard, planted in 2001 and located in the Po valley, northeastern Italy. Very few studies have conducted long-term investigations of root dynamics of fruit crops. Our main objective was to determine whether organic fertilizers affect root dynamics differently than mineral fertilizers. The experiment was a completely randomized block design with four replicates of three treatments: unfertilized, mineral fertilized and composted with municipal waste. Mineral fertilizers included P (100 kg ha(-1) year(-1)) and K (200 kg ha(-1) year(-1)) applied only at planting and N (70-130 kg ha(-1) year(-1)) split into two applications, one at 40 days after full bloom (60%) and the other in September (40%) each year. The compost fertilization represented a yearly rate of 10 metric tons (t) dry weight ha(-1), which approximates (in kg ha(-1) year(-1)) 240 N, 100 P and 200 K, split similarly to that described for the mineral fertilization of N. Both root growth and survival were evaluated at 20-day intervals during the growing season by the minirhizotron technique. Compost increased the production of new roots compared with the other treatments (P < 0.01). Roots were mainly produced at a depth of 41-80 cm and from March to May and in late summer. An analysis of covariance indicated no significant effect of soil nitrate on root production (P = 0.47). The root lifespan was longer in compost-treated trees than in mineral-fertilized or unfertilized trees (P < 0.01) and it was strongly affected by time of birth; roots born later in the summer lived longer than those born in the spring. Across years and treatments, the average root lifespan was positively correlated with soil nitrate (r = 0.60; P < 0.001). Variation in root lifespan with method of fertilization could be accounted for by variation in soil nitrate concentration as indicated by no effect of fertilizer treatment on root lifespan when soil nitrate was included as a covariate. These results reveal how shifting from mineral to organic fertilizers may shift both soil properties and nutrient availability, leading to changes in both root production and lifespan.

An optimized experimental strategy for efficient conversion of embryonic stem (ES)-derived mouse neural stem (NS) cells into a nearly homogeneous mature neuronal population.

NS cells are a homogeneous population of neural stem cells which were previously derived from embryonic stem cells as well as from the fetal and adult brain. Our previous reports have described a 21 day long neuronal differentiation protocol able to reproducibly convert adult SVZ-derived NS (aNS) cells into a population composed of 65% mature neurons and 35% glial cells. Here we have developed a different procedure specifically applicable to ES-derived NS cells in order to fully explore their neurogenic capacity. Differently from the aNS differentiation procedure, optimized neuronal output from ES-derived NS cells requires replating of the cells on appropriate substrates followed by sequential exposure to modified media. In these conditions, ES-derived NS cells differentiate into neurons with a barely appreciable quota of astrocytes and occasional oligodendrocytes. In particular, 21 days after the beginning of the treatment, 85% of the cells has differentiated into molecularly and electrophysiologically mature neurons belonging to the GABAergic lineage. The procedure, which is applicable with no considerable differences to different ES-derived NS cell lines and to NS cells at different passages, opens to the possibility of molecular and biochemical studies on close-to-uniform stem cell derived neurons.

Effect of compost application on the dynamics of carbon in a nectarine orchard ecosystem.

The aim of the present study was to compare the quantity and the type of carbon (C) stored during the 14-year lifetime of a commercial nectarine orchard ecosystem fertilized with mineral or organic fertilizers. The study was carried out in the Po valley, Italy, in a nectarine orchard of the variety Stark RedGold, grafted on GF677 hybrid peach × almond. Since orchard planting in August 2001, the following treatments were applied in a randomized complete block design with four replicates per block and compared: 1. unfertilized control; 2. mineral fertilization (including P and K at planting and N applied as NO3NH4 yearly at the rate of 70-130 kg ha-1); 3. compost application at a rate of 5 Mg DW ha-1 yr-1; 4. compost application at a rate of 10 Mg DW ha-1 yr-1. Compost was obtained from domestic organic wastes mixed with pruning material from urban ornamental trees and garden management after a 3-month stabilization period. Application of compost at the highest rate increased C in the soil; the amount of C sequestered was approximately 60% from amendment source and 40% from the net primary production of trees and grasses with a net increase of C compared to mineral fertilization. Compost application was found to be a win-win strategy to increase C storage in soil and, at the same time, to promote plant growth and yield to levels similar to those obtained with mineral fertilization. The rate of C application is crucial, indicated by the fact that compost supply at the rate of 10 Mg ha-1 yr-1 was the only fertilization strategy of the ones tested that resulted in higher C sequestration. This shows that compost amendment may stimulate an increase in the net primary production of plants.

Differentiating embryonic stem-derived neural stem cells show a maturation-dependent pattern of voltage-gated sodium current expression and graded action potentials.

A population of mouse embryonic stem (ES)-derived neural stem cells (named NS cells) that exhibits traits reminiscent of radial glia-like cell population and that can be homogeneously expanded in monolayer while remaining stable and highly neurogenic over multiple passages has been recently discovered. This novel population has provided a unique in vitro system in which to investigate physiological events occurring as stem cells lose multipotency and terminally differentiate. Here we analysed the timing, quality and quantity of the appearance of the excitability properties of differentiating NS cells which have been long-term expanded in vitro. To this end, we studied the biophysical properties of voltage-dependent Na(+) currents as an electrophysiological readout for neuronal maturation stages of differentiating NS cells toward the generation of fully functional neurons, since the expression of neuronal voltage-gated Na(+) channels is an essential hallmark of neuronal differentiation and crucial for signal transmission in the nervous system. Using the whole cell and single-channel cell-attached variations of the patch-clamp technique we found that the Na(+) currents in NS cells showed substantial electrophysiological changes during in vitro neuronal differentiation, consisting mainly in an increase of Na(+) current density and in a shift of the steady-state activation and inactivation curves toward more negative and more positive potentials respectively. The changes in the Na(+) channel system were closely related with the ability of differentiating NS cells to generate action potentials, and could therefore be exploited as an appropriate electrophysiological marker of ES-derived NS cells undergoing functional neuronal maturation.

Design of surface properties of PET films: effect of fluorinated block copolymers.

This paper demonstrates that the addition of fluorinated block copolymers to PET solutions can be used to prepare PET films with controlled surface morphology, porosity and chemical composition, by exploiting the phenomenon known as breath figures (BF) formation during a spin-coating procedure. Surface features, such as number, depth and diameter of pores and chemical composition, can be tuned by varying the experimental conditions: relative humidity, solution composition and amount of the fluorinated block copolymer added to the PET solutions (in the range of 0.5-10 wt% with respect to PET). BF patterns are more evident at relatively high concentrations of PET (3 wt%) and content of fluorinated block copolymer (10 wt% with respect to PET) in the solution. According to the obtained results, the fluorinated block copolymer seems to play a role in different steps of the mechanism of BF formation. XPS measurements showed a surface composition much richer in fluorinated segments than expected from bulk composition. The combined surface roughness and surface segregation of fluorinated segments have only a limited effect on the macroscopic wettability of the surfaces.

Identification of two mutations in cis in the SCN1A gene in a family showing genetic epilepsy with febrile seizures plus (GEFS+) and idiopathic generalized epilepsy (IGE).

Mutations in the SCN1A gene causing either loss or gain of function have been frequently found in patients affected by genetic epilepsy with febrile seizures plus (GEFS+) or Dravet syndrome (also named severe myoclonic epilepsy in infancy SMEI). By mutation screening of the SCN1A gene, we identified for the first time a case of two missense mutations in cis (p.[Arg1525Gln;Thr297Ile]) in all affected individuals of an Italian family showing GEFS+ and idiopathic generalized epilepsy (IGE). The p.Arg1525Gln mutation was not previously reported yet and was predicted to be pathological by prediction tools, whereas the p.Thr297Ile was already identified in patients showing SMEI. Functional studies revealed that the Nav1.1 channels harboring both mutations were characterized by a significant shift in the activation curve towards more positive potentials. Our data demonstrate that the p.Arg1525Gln represents a novel mutation in the SCN1A gene altering the channel properties in the co-presence of the p.Thr297Ile.

Calorimetric study of manganese binding to concanavalin A.

The reaction of concanavalin A with Mn2+ has been studied calorimetrically. The binding enthalpy was measured at two different temperatures, 25 and 30 degrees C, in 10(-3) M acetate buffer; it was found to be constant between pH 4.0 and 5.0, delta H250 = 95 kJ/mol and delta H300 = 65 kJ/mol, respectively. The two S1 binding sites are identical and independent. Experiments at pH 5.6 are distorted by the heat of aggregation, which is several times higher than the heat of binding. Aggregation was demonstrated by spectrophotometric experiments and by light scattering. The presence of Mn2+ increases the stability of the protein molecule.

[Rotavirus diarrhea in a population covered by private health insurance in Córdoba, Argentina]. / Diarrea por rotavirus en una población hospitalaria privada de Córdoba (Argentina).

BACKGROUND: Rotavirus is the most common cause of severe diarrhea worldwide, especially in children under 5 years of age. OBJECTIVES: To study the incidence of rotavirus diarrhea in a population in Cordoba, Argentina. To determine signs and symptoms with potential predictive clinical diagnostic value and evaluate how rotavirus diarrhea affects length of hospital stay. MATERIAL AND METHODS: A case-control study was performed from April 1, 2002 to March 31, 2003. RESULTS: Seventy-three patients were included. There were 33 rotavirus (1) cases and 40 rotavirus (-) controls. The mean age of the rotavirus (1) patients was 16.8 6 2.3 months. There were 14 (42.4 %; 95 % CI: 27.2-59.2) girls and 19 (57.6 %; 95 % CI: 40.8-72.8) boys. The seasonal peak of the disease was observed in the fall (30.3 %; 95 % CI: 17.4-47.3) and at the beginning of the austral winter (39.3 %; 95 % CI: 24.7-56.3). The signs and symptoms associated with the infection were vomiting (OR 8.40; 95 % CI: 2.39-31.33) and dehydration (OR 3.73; 95 % CI: 1.06-13.81). In the 33 rotavirus (1) patients, the mean length of hospital stay was 2.6 days. CONCLUSIONS: One half of the hospitalized cases were produced by rotavirus. The seasonal peak was observed in autumn and winter (southern hemisphere). Rotavirus (1) patients more frequently presented severe vomiting and dehydration than rotavirus (-) patients, although length of hospital stay and diarrhea were longer in the control group.

Characterization of a Voltage-dependent Calcium Current in the Human Neuroblastoma Cell Line SH-SY5Y During Differentiation.

In the presence of retinoic acid, cultured human neuroblastoma SH-SY5Y cells grow processes indicative of neuronal differentiation. A voltage-gated Ca current is already present in undifferentiated cells. A gradual increase of the Ca current density occurs during cell differentiation. According to kinetic and pharmacological properties, Ca currents in differentiated cells are indistinguishable from those elicitable in undifferentiated cells and resemble features of the high-voltage activated currents present in mammalian neuronal cells. omega-conotoxin strongly depresses high-voltage activated currents, both in undifferentiated and in differentiated SH-SY5Y cells. Interestingly, the Ca agonist Bay K 8644 is effective, albeit with great variability from cell to cell, only in differentiated cells and only when barium is the current carrier through the Ca channels. A diversity of high-voltage activated Ca channels of distinct pharmacology has been recently observed in other kinds of neurons. This requires a redefinition of the role that voltage-dependent Ca channel subtypes can play in mammalian neurons.

Opposing effects of acetylcholine on the two classes of voltage-dependent calcium channels in hippocampal neurons.

Acetylcholine (Ach) was tested for its effect on calcium currents in primary cultures of embryonic rat hippocampal neurons. Ach reversibly depressed, in a dose-dependent way, the high voltage activated (HVA) Ca currents. The effect was antagonized by atropine. Our results suggest that a pertussis toxin (PTX)-sensitive GTP binding protein (G-protein) is involved in the signal transduction mechanism between the Ach receptor and the HVA Ca channel. Activating rather than depressive effects of Ach were observed on the low voltage-activated component of Ca currents. This effect was also antagonized by atropine but is not mediated by a PTX-sensitive G-protein.

Baclofen inhibits high-threshold calcium currents with two distinct modes in rat hippocampal neurons.

In primary cultures of hippocampal neurons, activation of GABAB receptors reversibly inhibits high-voltage activated (HVA) Ca currents. In some neurons the GABAB agonist baclofen produces slow down of Ca current activation. In these cells the inhibitory action of the agonist can be relieved by strong pre-conditioning depolarizations. In other cells, where no significant changes in activation kinetics could be observed during agonist application, conditioning prepulses are nearly ineffective to recover the current from inhibition. Thus, in hippocampal neurons, activation of GABAergic receptors can modulate Ca currents with two different modes: one is voltage-dependent and the other is voltage-independent. In the presence of omega-conotoxin (omega-CgTx), only the second mode is prevented, suggesting that the two modulatory mechanisms (voltage-dependent and voltage-independent) operate in different cells on separate classes of HVA Ca channels.

Pharmacological characterization of voltage-dependent calcium currents in rat hippocampal neurons.

The kinetics and pharmacology of voltage-dependent calcium (Ca) currents in primary cultures of hippocampal neurons were studied using the whole cell clamp technique. The low voltage-activated (LVA) Ca current was activated at -50 mV and completely inactivated within 100 ms. This current was insensitive to omega-conotoxin (omega-CgTx) and to the calcium agonist Bay K 8644. The high-voltage-activated (HVA) Ca current was activated at -20 mV and inactivated incompletely during pulses of 200 ms duration. The snail toxin omega-CgTx revealed two pharmacological components of the HVA Ca current, one irreversibly blocked and the other insensitive to the toxin. Bay K 8644 had a clear agonistic action mainly on the omega-CgTx insensitive component of the HVA Ca current.

Acetylcholine-induced currents at plasma membrane of the frog oocyte.

Although with remarkable variability, membrane permeability in Rana oocytes can be modified by application of acetylcholine. The experiments were carried out in voltage-clamp conditions. Like in Xenopus, the responses proved to be related to activation of muscarinic receptors operating membrane channels probably selective for Cl-. At differences with Xenopus, the net acetylcholine-induced current showed remarkable deviation from linearity, displaying outward-going rectification. Application of acetylcholine typically produced opening of membrane channels, while in late spring, we observed the opposite effect in several batches of oocytes.

Calcium-dependent chloride transient currents in the immature oocyte of the frog, Rana esculenta.

Transient currents of chloride were studied in the plasma membrane of immature frog oocyte in voltage clamp conditions. The transients appeared to be activated by an influx of Ca2+ from the external medium. The mechanism leading to a surge of intracellular Ca2+ concentration needed at least 30 sec before full recovery. It was inhibited by substituting Ba2+ for Ca2+ in the external medium, or in the presence of La3+, Co2+ and Cd2+, or when external Na+ was replaced by Li+. Verapamil proved ineffective. The data suggest that an intracellular system of Ca-activated Ca-release is present in the frog oocyte, which can be primarily activated by membrane hyperpolarization via an influx of Ca2+ through non-selective channels.

Role of motor imitation in traversability of surfaces by walking infants.

The ecological approach by Gibson stressed the role of visual cues in toddlers' locomotor activities. In particular, a rigid surface offers more traversability "affordances" to walkers (13-16 mo. old) than a deformable surface. On the other hand, imitation plays a relevant role in human behaviors. In our study a group of 17 walking infants (12-19 mo.) were asked to choose between locomoting on a rigid versus a deformable surface after having seen an older child walking on the deformable surface. A control group of 19 infants were asked to do the same task without having seen a model. The task was repeated three times. No relevant differences appeared between the two groups as to the choice of surfaces: the rigid surface was preferred by both groups. Some slight differences in the behavior of the experimental group were seen as a result of observing the model. Clearly, however, social stimulus. such as the sight of an older child performing a specific task, does not overcome the affordances which induce infants not to walk on the deformable surface.

Setting the conditions for efficient, robust and reproducible generation of functionally active neurons from adult subventricular zone-derived neural stem cells.

Although new culture conditions enable homogeneous and long-term propagation of radial glia-like neural stem (NS) cells in monolayer and serum-free conditions, the efficiency of the conversion of NS cells into terminally differentiated, functionally mature neurons is relatively limited and poorly characterized. We demonstrate that NS cells derived from adult mouse subventricular zone robustly develop properties of mature neurons when exposed to an optimized neuronal differentiation protocol. A high degree of cell viability was preserved. At 22 days in vitro, most cells (65%) were microtubule-associated protein 2(+) and coexpressed gamma-aminobutyric acid (GABA), GAD67, calbindin and parvalbumin. Nearly all neurons exhibited sodium, potassium and calcium currents, and 70% of them fired action potentials. These neurons expressed functional GABA(A) receptors, whereas activable kainate, alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid and N-methyl-D-aspartic acid receptors were present in approximately 80, 30 and 2% of cells, respectively. Antigenic and functional properties were efficiently and reliably reproduced across experiments and cell passages (up to 68). This is the first report showing a consistent and reproducible generation of large amounts of neurons from long-term passaged adult neural stem cells. Remarkably, the neuronal progeny carries a defined set of antigenic, biochemical and functional characteristics that make this system suitable for studies of NS cell biology as well as for genetic and chemical screenings.

A fast transient outward current in layer II/III neurons of rat perirhinal cortex.

The perirhinal cortex (PRC) is a supra-modal cortical area that collects and integrates information originating from uni- and multi-modal neocortical regions, transmits it to the hippocampus, and receives a feedback from the hippocampus itself. The elucidation of the mechanisms that underlie the specific excitable properties of the different PRC neuronal types appears as an important step toward the understanding of the integrative functions of PRC. In this study, we investigated the biophysical properties of the transient, I (A)-type K(+) current recorded in pyramidal neurons acutely dissociated from layers II/III of PRC of the rat (P8-P16). The current activated at about -50 mV and showed a fast monoexponential decay (tau(h) >> 14 ms at -30 to +10 mV). I (A) recovery from inactivation also had a monoexponential time course. No significant differences in the biophysical properties or current density of I (A) were found in pyramidal neurons from rats of different ages. Application of 4-AP (1-5 mM) reversibly and selectively blocked I (A), and in current clamp conditions it increased spike duration and shortened the delay of the first spike during repetitive firing evoked by sustained depolarizing current injection. These properties are similar to those of the I (A) found in thalamic neurons and other cortical pyramidal neurons. Our results suggest that I (A) contributes to spike repolarization and to regulate both spike onset timing and firing frequency in PRC neurons.