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1.
J Neurophysiol ; 2024 Jul 11.
Article in English | MEDLINE | ID: mdl-38988287

ABSTRACT

Generation of human induced pluripotent stem cells (iPSCs) through reprogramming was a transformational change in the field of regenerative medicine that led to new possibilities for drug discovery and cell replacement therapy. Several protocols have been established to differentiate hiPSCs into neuronal lineages. However, low differentiation efficiency is one of the major drawbacks of these approaches. Here, we compared the efficiency of two methods of neuronal differentiation from iPSCs cultured in two different culture media, StemFlex Medium (SFM) and Essential 8 Medium (E8M). The results indicated that iPSCs cultured in E8M efficiently generated different types of neurons in a shorter time and without the growth of undifferentiated non-neuronal cells in the culture as compared to those generated from iPSCs in SFM. Furthermore, these neurons were validated as functional units immunocytochemically by confirming the expression of mature neuronal markers (i.e., NeuN, Beta tubulin, and Synapsin I), and whole-cell patch-clamp recordings. Long-read single-cell RNA sequencing confirms the presence of upper and deep layer cortical layer excitatory and inhibitory neuronal subtypes in addition to small populations of GABAergic neurons in day 30 neuronal cultures. Pathway analysis indicated that our protocol triggers the signaling transcriptional networks important for the process of neuronal differentiation in vivo.

2.
Physiol Plant ; 175(6): e14066, 2023.
Article in English | MEDLINE | ID: mdl-38148241

ABSTRACT

Abiotic stress has been shown to induce the formation of reactive oxygen species (ROS) in plant cells. When the level of ROS surpasses the capacity of the endogenous defence mechanism, oxidative stress status is reached, leading to plant damage and a drop in crop productivity. Under oxidative stress conditions, ROS can react with polyunsaturated fatty acids to form oxidized derivatives called phytoprostanes (PhytoPs) and phytofurans (PhytoFs), which are recognized as biomarkers of oxidative damage advance. Modern agriculture proposes the use of biostimulants as a sustainable strategy to alleviate the negative effects of oxidative stress on plants. This work evaluates the dose effect of natural antioxidant extract to mitigate the oxidative-stress deleterious effects in melon and sweet pepper exposed to thermal stress. The plants were sprayed with Ilex paraguariensis (IP) aqueous extract in three different concentrations before exposure to abiotic stress. PhytoP and PhytoF levels were determined in the leaves of melon and pepper plants. IP1 and IP2 were effective against oxidative stress in both plants, with IP1 being the most protective one. IP1 decreased the levels of PhytoPs and PhytoFs by roughly 44% in both melon plants and pepper plants. The yield, with IP1, increased by 57 and 39% in stressed melon and pepper plants, respectively. IP3 foliar application in melon plants induced a pro-oxidant effect rather than the expected mitigating action. However, in sweet pepper plants, IP3 decreased the oxidative stress progress and increased the fruit yield.


Subject(s)
Ilex paraguariensis , Ilex paraguariensis/metabolism , Reactive Oxygen Species , Oxidative Stress , Antioxidants/pharmacology , Antioxidants/metabolism , Crops, Agricultural
3.
Sci Total Environ ; 905: 166990, 2023 Dec 20.
Article in English | MEDLINE | ID: mdl-37704132

ABSTRACT

European semi-natural dry grasslands are among the most endangered terrestrial ecosystems, being recognised as habitats of community interest by the EU Habitats Directive. The occurrence and preservation of these habitats depend on a combination of anthropogenic and natural factors, although little is known regarding the role of past land-use changes. Here, we investigated the role of time since cultivation abandonment as a major driver of grassland successional dynamics in the Mediterranean agro-pastoral system of Alta Murgia, southern Italy. By integrating cartographic information on the past agricultural land-use with the main abiotic constraints (patch area, slope and aspect), we used generalised additive mixed models to test for the probability of occurrence of current grassland habitat types along time since cultivation abandonment (10 to 200 years). Our results disclosed the successional sequence of grassland plant communities since crop abandonment in the study area, highlighting that the distribution of semi-natural grassland communities largely depends on land use history besides current environmental patterns. Among the habitat types protected under the EU Habitats Directive, we highlighted that xero-thermic communities may represent an intermediate step of grassland succession after cultivation abandonment, while more mesic perennial communities indicate a late successional stage. These successional dynamics are further modulated by mesoclimatic conditions associated with slope and aspect, especially in case of long-standing pastures that were not historically affected by agricultural transformations. Our findings can contribute to a deeper understanding of dynamics relevant to spontaneous vegetation recovery in open environments, which is a prerequisite for setting up effective grassland conservation and restoration actions. Furthermore, our results underline the value of integrating historical maps and current information for the assessment of habitat conservation status.


Subject(s)
Ecosystem , Grassland , Biodiversity , Agriculture/methods , Italy
4.
Rev Med Virol ; 33(6): e2482, 2023 11.
Article in English | MEDLINE | ID: mdl-37749807

ABSTRACT

Human bocaviruses were first described between 2005 and 2010, identified in respiratory and enteric tract samples of children. Screening studies have shown worldwide distribution. Based on phylogenetic analysis, they were classified into four genotypes (HBoV1-4). From a clinical perspective, human bocavirus 1 (HBoV1) is considered the most relevant, since it can cause upper and lower acute respiratory tract infection, mainly in infants, including common cold, bronchiolitis, and pneumonia, as well as wheezing in susceptible patients. However, the specific processes leading to structural, biochemical, and functional changes resulting in the different clinical presentations have not been elucidated yet. This review surveys the interactions between the virus and target cells that can potentially explain disease-causing mechanisms. It also summarises the clinical phenotype of cases, stressing the role of HBoV1 as an aetiological agent of lower acute respiratory infection in infants, together with laboratory tests for detection and diagnosis. By exploring the current knowledge on the epidemiology of HBoV1, insights into the complex scenario of paediatric respiratory infections are presented, as well as the potential effects that changes in the circulation can have on the dynamics of respiratory agents, spotlighting the benefits of comprehensively increase insights into incidence, interrelationships with co-circulating agents and potential control of HBoV1.


Subject(s)
Human bocavirus , Parvoviridae Infections , Respiratory Tract Infections , Infant , Child , Humans , Human bocavirus/genetics , Phylogeny , Respiratory Tract Infections/diagnosis , Respiratory Tract Infections/epidemiology , Virus Replication , Cell Communication , Parvoviridae Infections/diagnosis , Parvoviridae Infections/epidemiology
5.
Diagn Microbiol Infect Dis ; 107(3): 116050, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37597460

ABSTRACT

Acute respiratory infections represent the leading cause of morbimortality in children and viruses are the main etiological agents. Here we describe the clinical characteristics and evolution of infants admitted to intensive care unit with severe acute respiratory infection (SARI) due to Human Bocavirus 1 mono-infection in patients without previous comorbidity. We also compared them with respiratory syncytial virus (RSV) cases. Of 141 cases included (age 5.43 ± 4.54 months, 52% male), 80% had at least 1 virus detected. RSV was the most frequent in the series (71.6%) followed by HBoV1 (28%). Five cases of HBoV1 mono-detection were identified. Pediatric acute respiratory distress syndrome was present in both groups, HBoV1 and RSV. The clinical presentation and evolution of HBoV1 single infection was similar to RSV. HBoV1 should be included among the agents investigated in cases of SARI in infants.


Subject(s)
Human bocavirus , Parvoviridae Infections , Respiratory Syncytial Virus Infections , Respiratory Syncytial Virus, Human , Respiratory Tract Infections , Humans , Child , Infant , Male , Infant, Newborn , Female , Parvoviridae Infections/diagnosis , Parvoviridae Infections/epidemiology , Respiratory Tract Infections/diagnosis , Respiratory Tract Infections/epidemiology , Intensive Care Units , Respiratory Syncytial Virus Infections/diagnosis , Respiratory Syncytial Virus Infections/epidemiology , Acute Disease
6.
Proc Natl Acad Sci U S A ; 120(31): e2207978120, 2023 08.
Article in English | MEDLINE | ID: mdl-37487086

ABSTRACT

Loss-of-function mutations in the KCNA1(Kv1.1) gene cause episodic ataxia type 1 (EA1), a neurological disease characterized by cerebellar dysfunction, ataxic attacks, persistent myokymia with painful cramps in skeletal muscles, and epilepsy. Precision medicine for EA1 treatment is currently unfeasible, as no drug that can enhance the activity of Kv1.1-containing channels and offset the functional defects caused by KCNA1 mutations has been clinically approved. Here, we uncovered that niflumic acid (NFA), a currently prescribed analgesic and anti-inflammatory drug with an excellent safety profile in the clinic, potentiates the activity of Kv1.1 channels. NFA increased Kv1.1 current amplitudes by enhancing the channel open probability, causing a hyperpolarizing shift in the voltage dependence of both channel opening and gating charge movement, slowing the OFF-gating current decay. NFA exerted similar actions on both homomeric Kv1.2 and heteromeric Kv1.1/Kv1.2 channels, which are formed in most brain structures. We show that through its potentiating action, NFA mitigated the EA1 mutation-induced functional defects in Kv1.1 and restored cerebellar synaptic transmission, Purkinje cell availability, and precision of firing. In addition, NFA ameliorated the motor performance of a knock-in mouse model of EA1 and restored the neuromuscular transmission and climbing ability in Shaker (Kv1.1) mutant Drosophila melanogaster flies (Sh5). By virtue of its multiple actions, NFA has strong potential as an efficacious single-molecule-based therapeutic agent for EA1 and serves as a valuable model for drug discovery.


Subject(s)
Myokymia , Animals , Mice , Drosophila melanogaster , Ataxia , Drosophila , Kv1.2 Potassium Channel
7.
Sci Rep ; 13(1): 5695, 2023 04 07.
Article in English | MEDLINE | ID: mdl-37029149

ABSTRACT

Xylella fastidiosa subsp. pauca (Xfp), has attacked the olive trees in Southern Italy with severe impacts on the olive agro-ecosystem. To reduce both the Xfp cell concentration and the disease symptom, a bio-fertilizer restoration technique has been used. Our study applied multi-resolution satellite data to evaluate the effectiveness of such technique at both field and tree scale. For field scale, a time series of High Resolution (HR) Sentinel-2 images, acquired in the months of July and August from 2015 to 2020, was employed. First, four spectral indices from treated and untreated fields were compared. Then, their trends were correlated to meteo-events. For tree-scale, Very High Resolution (VHR) Pléiades images were selected at the closest dates of the Sentinel-2 data to investigate the response to treatments of each different cultivar. All indices from HR and VHR images were higher in treated fields than in those untreated. The analysis of VHR indices revealed that Oliarola Salentina can respond better to treatments than Leccino and Cellina cultivars. All findings were in agreement with in-field PCR results. Hence, HR data could be used to evaluate plant conditions at field level after treatments, while VHR imagery could be used to optimize treatment doses per cultivar.


Subject(s)
Olea , Xylella , Fertilizers , Ecosystem , Xylella/physiology , Plant Diseases/prevention & control
8.
Viral Immunol ; 36(6): 429-434, 2023.
Article in English | MEDLINE | ID: mdl-37102675

ABSTRACT

We determined anti-rubella and anti-measles immunoglobulin G (IgG) in 7- to 19-year-old children and adolescents with vaccine only-induced immunity of Córdoba, Argentina, during a 6-month period over 2021-2022. Of the 180 individuals studied, 92.2% and 88.3% were positive for anti-measles and anti-rubella IgG, respectively. No significant differences were found comparing anti-rubella IgG concentrations (p = 0.144) and anti-measles IgG concentrations (p = 0.105) of individuals classified by age, but anti-measles IgG and anti-rubella IgG levels were significantly higher among female individuals compared with males (p = 0.031 and p = 0.036, respectively). Female subjects in the younger age group had higher concentrations of anti-rubella IgG as well (p = 0.020), even when anti-measles IgG concentrations did not differ among female age-subgroups (p = 0.187). In contrast, age subgroups of male individuals did not have significantly different IgG concentrations for rubella (p = 0.745) or measles (p = 0.124). Among samples with discordant results (22/180, 12.6%), 9.1% were negative for rubella but positive for measles; 13.6% were equivocal for rubella and positive for measles; 22.7% were equivocal for rubella and negative for measles, while 54.5% were positive for rubella but negative for measles. The findings indicate a seroprevalence below recommended for preventing measles in the population studied, while they evidence the need for standardization of serological tests for rubella IgG.


Subject(s)
Measles , Mumps , Rubella , Humans , Child , Male , Female , Adolescent , Young Adult , Adult , Seroepidemiologic Studies , Argentina/epidemiology , Antibodies, Viral , Rubella/epidemiology , Rubella/prevention & control , Measles/epidemiology , Measles/prevention & control , Measles-Mumps-Rubella Vaccine , Immunoglobulin G , Mumps/epidemiology , Mumps/prevention & control
9.
Int J Mol Sci ; 23(23)2022 Dec 05.
Article in English | MEDLINE | ID: mdl-36499661

ABSTRACT

Locus coeruleus (LC) neurons, with their extensive innervations throughout the brain, control a broad range of physiological processes. Several ion channels have been characterized in LC neurons that control intrinsic membrane properties and excitability. However, ERG (ether-à-go-go-related gene) K+ channels that are particularly important in setting neuronal firing rhythms and automaticity have not as yet been discovered in the LC. Moreover, the neurophysiological and pathophysiological roles of ERG channels in the brain remain unclear despite their expression in several structures. By performing immunohistochemical investigations, we found that ERG-1A, ERG-1B, ERG-2 and ERG-3 are highly expressed in the LC neurons of mice. To examine the functional role of ERG channels, current-clamp recordings were performed on mouse LC neurons in brain slices under visual control. ERG channel blockade by WAY-123,398, a class III anti-arrhythmic agent, increased the spontaneous firing activity and discharge irregularity of LC neurons. Here, we have shown the presence of distinct ERG channel subunits in the LC which play an imperative role in modulating neuronal discharge patterns. Thus, we propose that ERG channels are important players behind the changes in, and/or maintenance of, LC firing patterns that are implicated in the generation of different behaviors and in several disorders.


Subject(s)
Ether-A-Go-Go Potassium Channels , Locus Coeruleus , Mice , Animals , Locus Coeruleus/metabolism , Action Potentials , Ether-A-Go-Go Potassium Channels/genetics , Ether-A-Go-Go Potassium Channels/metabolism , Neurons/metabolism , Anti-Arrhythmia Agents/pharmacology
10.
Access Microbiol ; 4(10): acmi000428, 2022.
Article in English | MEDLINE | ID: mdl-36415736

ABSTRACT

Human parvovirus B19 (B19V) is the aetiological agent of erythema infectiosum. Primary infection during pregnancy can be transmitted to the foetus and cause foetal abnormalities related to depletion of erythrocyte progenitor cells, including congenital anaemia, hydrops, and foetal death. In this paper we report the detection of B19V infection in a pregnant patient, which onset occurred without appreciable signs and symptoms until she developed inappropriate contractions for gestational age and fluid loss. B19V infection resulted in severe hydrops fetalis with a fatal course for the foetus, while persisted in the mother at least 12 months after foetal death. The objective of this report is to highlight the importance of optimizing B19V diagnosis through early suspicion and testing during pregnancy. Knowing the mother's immune status before or at the beginning of gestation can contribute, together with early diagnosis, to improve the management of patients at risk.

11.
J Med Microbiol ; 71(10)2022 Oct.
Article in English | MEDLINE | ID: mdl-36301612

ABSTRACT

Introduction. Human bocavirus 1 (HBoV1) infection occurs with viral genome presence in respiratory secretions (RS) and serum, and therefore both samples can be used for diagnosis.Gap statement. The diagnostic sensitivity of HBoV1 DNA detection in serum and the duration of DNAaemia in severe clinical cases have not been elucidated.Aim. To determine HBoV1 DNA in serum and RS of paediatric patients hospitalized for lower acute respiratory infection (LARI) and to analyse the clinical-epidemiological features of positive cases.Methodology. This was a prospective, transverse study. Physicians selected the clinical situations and obtained paired clinical samples (RS and serum) that were tested by PCR/qPCR for HBoV1. Positive cases were analysed considering time of specimen collection, co-detection, clinical manifestations and viral load; statistical significant level was set at α=0.05.Results. HBoV1 was detected in 98 of 402 cases included (24 %); 18/98 (18 %) patients had the virus detectable in serum and 91/98 (93 %) in RS (P<0.001). Positivity rates were not significantly different in patients with RS and serum collected within or beyond 24 h of admission. Single HBoV1 infection was identified in 39/98 patients (40 %), three patients had HBoV1 in both clinical samples (3/39, 8 %) and 32 (32/39, 82 %) only in RS, 22 of them (69 %) with both clinical samples within 24 h of admission. Cough (P=0.001) and rhinitis (P=0.003) were significantly frequent among them and most patients were diagnosed with bronchiolitis (22/39, 56 %) and pneumonia (9/39, 23 %), which was more frequent compared to cases with co-infection (P=0.04). No significant differences were identified among patients with high, medium or low viral load of HBoV1 regarding rate of positivity in both clinical samples, the time of collection of RS and serum, co-detection, first episode of LARI, clinical manifestations, comorbidity or requirement for assisted ventilation. Intensive care unit (ICU) patients had a significantly higher frequency of detection (P<0.001) and co-detection (P=0.001) compared to patients on standard care.Conclusions. HBoV1 is prevalent among infant patients hospitalized for LARI and including it in the standard testing can add to the aetiological diagnosis in these cases, especially for patients admitted to the ICU. HBoV1 detection in serum did not contribute significantly to the diagnosis as compared to detection in respiratory secretions.


Subject(s)
Human bocavirus , Parvoviridae Infections , Respiratory Tract Infections , Infant , Humans , Child , Human bocavirus/genetics , Prospective Studies , Parvoviridae Infections/diagnosis , Respiratory Tract Infections/diagnosis , Real-Time Polymerase Chain Reaction
12.
Cells ; 11(17)2022 08 26.
Article in English | MEDLINE | ID: mdl-36078064

ABSTRACT

Astrocytes, the main glial cells of the central nervous system, play a key role in brain volume control due to their intimate contacts with cerebral blood vessels and the expression of a distinctive equipment of proteins involved in solute/water transport. Among these is MLC1, a protein highly expressed in perivascular astrocytes and whose mutations cause megalencephalic leukoencephalopathy with subcortical cysts (MLC), an incurable leukodystrophy characterized by macrocephaly, chronic brain edema, cysts, myelin vacuolation, and astrocyte swelling. Although, in astrocytes, MLC1 mutations are known to affect the swelling-activated chloride currents (ICl,swell) mediated by the volume-regulated anion channel (VRAC), and the regulatory volume decrease, MLC1's proper function is still unknown. By combining molecular, biochemical, proteomic, electrophysiological, and imaging techniques, we here show that MLC1 is a Ca2+/Calmodulin-dependent protein kinase II (CaMKII) target protein, whose phosphorylation, occurring in response to intracellular Ca2+ release, potentiates VRAC-mediated ICl,swell. Overall, these findings reveal that MLC1 is a Ca2+-regulated protein, linking volume regulation to Ca2+ signaling in astrocytes. This knowledge provides new insight into the MLC1 protein function and into the mechanisms controlling ion/water exchanges in the brain, which may help identify possible molecular targets for the treatment of MLC and other pathological conditions caused by astrocyte swelling and brain edema.


Subject(s)
Brain Edema , Cysts , Astrocytes/metabolism , Brain Edema/pathology , Calcium-Calmodulin-Dependent Protein Kinase Type 2/metabolism , Chlorides/metabolism , Cysts/metabolism , Hereditary Central Nervous System Demyelinating Diseases , Humans , Membrane Proteins/metabolism , Proteomics , Voltage-Dependent Anion Channels/metabolism , Water/metabolism
13.
Int J Mol Sci ; 23(15)2022 Jul 22.
Article in English | MEDLINE | ID: mdl-35897654

ABSTRACT

Mutations in the KCNA1 gene, encoding the voltage-gated potassium channel Kv1.1, have been associated with a spectrum of neurological phenotypes, including episodic ataxia type 1 and developmental and epileptic encephalopathy. We have recently identified a de novo variant in KCNA1 in the highly conserved Pro-Val-Pro motif within the pore of the Kv1.1 channel in a girl affected by early onset epilepsy, ataxia and developmental delay. Other mutations causing severe epilepsy are located in Kv1.1 pore domain. The patient was initially treated with a combination of antiepileptic drugs with limited benefit. Finally, seizures and ataxia control were achieved with lacosamide and acetazolamide. The aim of this study was to functionally characterize Kv1.1 mutant channel to provide a genotype-phenotype correlation and discuss therapeutic options for KCNA1-related epilepsy. To this aim, we transfected HEK 293 cells with Kv1.1 or P403A cDNAs and recorded potassium currents through whole-cell patch-clamp. P403A channels showed smaller potassium currents, voltage-dependent activation shifted by +30 mV towards positive potentials and slower kinetics of activation compared with Kv1.1 wild-type. Heteromeric Kv1.1+P403A channels, resembling the condition of the heterozygous patient, confirmed a loss-of-function biophysical phenotype. Overall, the functional characterization of P403A channels correlates with the clinical symptoms of the patient and supports the observation that mutations associated with severe epileptic phenotype cluster in a highly conserved stretch of residues in Kv1.1 pore domain. This study also strengthens the beneficial effect of acetazolamide and sodium channel blockers in KCNA1 channelopathies.


Subject(s)
Epilepsy , Kv1.1 Potassium Channel , Acetazolamide , Ataxia/drug therapy , Ataxia/genetics , Epilepsy/drug therapy , Epilepsy/genetics , HEK293 Cells , Humans , Kv1.1 Potassium Channel/chemistry , Kv1.1 Potassium Channel/genetics , Mutation , Potassium
14.
Sci Total Environ ; 848: 157707, 2022 Nov 20.
Article in English | MEDLINE | ID: mdl-35908692

ABSTRACT

The aim of this work was to evaluate if rivers could be used for SARS-CoV-2 surveillance. Five sampling points from three rivers (AR-1 and AR-2 in Arenales River, MR-1 and MR-2 in Mojotoro River, and CR in La Caldera River) from Salta (Argentina), two of them receiving discharges from wastewater plants (WWTP), were monitored from July to December 2020. Fifteen water samples from each point (75 in total) were collected and characterized physico-chemically and microbiologically and SARS-CoV-2 was quantified by RT-qPCR. Also, two targets linked to human contributions, human polyomavirus (HPyV) and RNase P, were quantified and used to normalize SARS-CoV-2 concentration, which was compared to reported COVID-19 cases. Statistical analyses allowed us to verify the correlation between SARS-CoV-2 and the concentration of fecal indicator bacteria (FIB), as well as to find similarities and differences between sampling points. La Caldera River showed the best water quality; FIBs were within acceptable limits for recreational activities. Mojotoro River's water quality was not affected by the northern WWTP of the city. Instead, Arenales River presented the poorest water quality; at AR-2 was negatively affected by the discharges of the southern WWTP, which contributed to significant increase of fecal contamination. SARS-CoV-2 was found in about half of samples in low concentrations in La Caldera and Mojotoro Rivers, while it was high and persistent in Arenales River. No human tracers were detected in CR, only HPyV was found in MR-1, MR-2 and AR-1, and both were quantified in AR-2. The experimental and normalized viral concentrations strongly correlated with reported COVID-19 cases; thus, Arenales River at AR-2 reflected the epidemiological situation of the city. This is the first study showing the dynamic of SARS-CoV-2 concentration in an urban river highly impacted by wastewater and proved that can be used for SARS-CoV-2 surveillance to support health authorities.


Subject(s)
COVID-19 , SARS-CoV-2 , COVID-19/epidemiology , Humans , Polystyrenes , Ribonuclease P , Rivers , Wastewater
15.
Sci Rep ; 11(1): 20703, 2021 10 19.
Article in English | MEDLINE | ID: mdl-34667231

ABSTRACT

The effects of global warming have been addressed on coral reefs in tropical areas, while it is still unclear how coral forests are reacting, particularly at temperate latitudes. Here we show how mesophotic coral forests are affected by global warming in the Mediterranean Sea. We highlight how the current warming trend is causing the lowering of the thermocline and it is enhancing mucilaginous blooms. These stressors are facilitating a massive macroalgal epibiosis on living corals, here reported for the first time from different areas in the Western and Central Mediterranean Sea. We provide a focus of this phenomenon at Tremiti Islands Marine Protected Area (Adriatic Sea), were the density of the endemic red gorgonian Paramuricea clavata decreased of up to 47% in 5 years, while up to the 96% of the living corals showed signs of stress and macroalgal epibiosis. Only populations deeper than 60 m depth were not touched by this emerging phenomenon. Spot observations performed at Tuscan Archipelago and Tavolara Marine Protected Area (Tyrrhenian Sea) suggest that this this combination of stressors is likely widespread at basin scale.


Subject(s)
Anthozoa/physiology , Animals , Biodiversity , Coral Reefs , Ecosystem , Forests , Global Warming , Mediterranean Sea
16.
Int J Mol Sci ; 22(18)2021 Sep 14.
Article in English | MEDLINE | ID: mdl-34576077

ABSTRACT

Kv1.2 channels, encoded by the KCNA2 gene, are localized in the central and peripheral nervous system, where they regulate neuronal excitability. Recently, heterozygous mutations in KCNA2 have been associated with a spectrum of symptoms extending from epileptic encephalopathy, intellectual disability, and cerebellar ataxia. Patients are treated with a combination of antiepileptic drugs and 4-aminopyridine (4-AP) has been recently trialed in specific cases. We identified a novel variant in KCNA2, E236K, in a Serbian proband with non-progressive congenital ataxia and early onset epilepsy, treated with sodium valproate. To ascertain the pathogenicity of E236K mutation and to verify its sensitivity to 4-AP, we transfected HEK 293 cells with Kv1.2 WT or E236K cDNAs and recorded potassium currents through the whole-cell patch-clamp. In silico analysis supported the electrophysiological data. E236K channels showed voltage-dependent activation shifted towards negative potentials and slower kinetics of deactivation and activation compared with Kv1.2 WT. Heteromeric Kv1.2 WT+E236K channels, resembling the condition of the heterozygous patient, confirmed a mixed gain- and loss-of-function (GoF/LoF) biophysical phenotype. 4-AP inhibited both Kv1.2 and E236K channels with similar potency. Homology modeling studies of mutant channels suggested a reduced interaction between the residue K236 in the S2 segment and the gating charges at S4. Overall, the biophysical phenotype of E236K channels correlates with the mild end of the clinical spectrum reported in patients with GoF/LoF defects. The response to 4-AP corroborates existing evidence that KCNA2-disorders could benefit from variant-tailored therapeutic approaches, based on functional studies.


Subject(s)
4-Aminopyridine/therapeutic use , Cerebellar Ataxia/congenital , Cerebellar Ataxia/genetics , Epilepsy/drug therapy , Epilepsy/genetics , Kv1.2 Potassium Channel/genetics , Amino Acid Sequence , Brain/diagnostic imaging , Cerebellar Ataxia/diagnostic imaging , Cerebellar Ataxia/drug therapy , Child , Child, Preschool , Epilepsy/diagnostic imaging , Humans , Infant , Kv1.2 Potassium Channel/chemistry , Magnetic Resonance Imaging , Male , Molecular Dynamics Simulation , Young Adult
17.
Int J Mol Sci ; 22(11)2021 Jun 01.
Article in English | MEDLINE | ID: mdl-34205849

ABSTRACT

The ability of spermatozoa to swim towards an oocyte and fertilize it depends on precise K+ permeability changes. Kir5.1 is an inwardly-rectifying potassium (Kir) channel with high sensitivity to intracellular H+ (pHi) and extracellular K+ concentration [K+]o, and hence provides a link between pHi and [K+]o changes and membrane potential. The intrinsic pHi sensitivity of Kir5.1 suggests a possible role for this channel in the pHi-dependent processes that take place during fertilization. However, despite the localization of Kir5.1 in murine spermatozoa, and its increased expression with age and sexual maturity, the role of the channel in sperm morphology, maturity, motility, and fertility is unknown. Here, we confirmed the presence of Kir5.1 in spermatozoa and showed strong expression of Kir4.1 channels in smooth muscle and epithelial cells lining the epididymal ducts. In contrast, Kir4.2 expression was not detected in testes. To examine the possible role of Kir5.1 in sperm physiology, we bred mice with a deletion of the Kcnj16 (Kir5.1) gene and observed that 20% of Kir5.1 knock-out male mice were infertile. Furthermore, 50% of knock-out mice older than 3 months were unable to breed. By contrast, 100% of wild-type (WT) mice were fertile. The genetic inactivation of Kcnj16 also resulted in smaller testes and a greater percentage of sperm with folded flagellum compared to WT littermates. Nevertheless, the abnormal sperm from mutant animals displayed increased progressive motility. Thus, ablation of the Kcnj16 gene identifies Kir5.1 channel as an important element contributing to testis development, sperm flagellar morphology, motility, and fertility. These findings are potentially relevant to the understanding of the complex pHi- and [K+]o-dependent interplay between different sperm ion channels, and provide insight into their role in fertilization and infertility.


Subject(s)
Infertility, Male/genetics , Potassium Channels, Inwardly Rectifying/genetics , Spermatozoa/metabolism , Animals , Fertility/genetics , Gene Expression Regulation, Developmental/genetics , Infertility, Male/pathology , Male , Membrane Potentials/genetics , Mice , Mice, Knockout , Muscle, Smooth/metabolism , Oocytes/growth & development , Potassium/metabolism , Sperm Motility/genetics , Spermatozoa/growth & development , Testis/growth & development , Testis/metabolism , Kir5.1 Channel
18.
Int J Mol Sci ; 22(11)2021 Jun 04.
Article in English | MEDLINE | ID: mdl-34199759

ABSTRACT

The TWIK-related spinal cord potassium channel (TRESK) is encoded by KCNK18, and variants in this gene have previously been associated with susceptibility to familial migraine with aura (MIM #613656). A single amino acid substitution in the same protein, p.Trp101Arg, has also been associated with intellectual disability (ID), opening the possibility that variants in this gene might be involved in different disorders. Here, we report the identification of KCNK18 biallelic missense variants (p.Tyr163Asp and p.Ser252Leu) in a family characterized by three siblings affected by mild-to-moderate ID, autism spectrum disorder (ASD) and other neurodevelopment-related features. Functional characterization of the variants alone or in combination showed impaired channel activity. Interestingly, Ser252 is an important regulatory site of TRESK, suggesting that alteration of this residue could lead to additive downstream effects. The functional relevance of these mutations and the observed co-segregation in all the affected members of the family expand the clinical variability associated with altered TRESK function and provide further insight into the relationship between altered function of this ion channel and human disease.


Subject(s)
Alleles , Intellectual Disability/genetics , Mutation/genetics , Neurodevelopmental Disorders/genetics , Potassium Channels/genetics , Adolescent , Adult , Amino Acid Sequence , Animals , Base Sequence , Calcineurin/metabolism , Female , Genome, Human , Humans , Ion Channel Gating/drug effects , Ionomycin/pharmacology , Male , Pedigree , Potassium Channels/chemistry , Siblings , Xenopus laevis/metabolism , Young Adult
19.
Toxicol Pathol ; 49(5): 1117-1125, 2021 07.
Article in English | MEDLINE | ID: mdl-34077280

ABSTRACT

The most common target organ for toxicity in the endocrine system is the adrenal gland, and its function is dependent upon the hypothalamus and pituitary gland. Histopathologic examination of the adrenal glands and pituitary gland is routinely performed in toxicity studies. However, the function of the adrenal gland is not routinely assessed in toxicity studies. Assessment of adrenal cortical function may be necessary to determine whether a histopathologic finding in the adrenal cortex results in a functional effect in the test species. As juvenile toxicity studies are more commonly performed in support of pediatric indications for pharmaceuticals, it is important to establish historical control data for adrenal gland function. In this study, adrenal cortical function was assessed in control neonatal and weanling beagle dogs as part of an ongoing juvenile toxicology program. Measurements of serum adrenocorticotropic hormone (ACTH), cortisol prior to and following administration of exogenous ACTH, and aldosterone were conducted beginning at 2 weeks of age continuing through 26 weeks of age. Serum electrolyte concentrations were determined at 4, 13, and 26 weeks of age. Dogs as young as 2 weeks of age synthesize and secrete adrenal cortical hormones and exhibit a functional hypothalamic pituitary adrenal axis.


Subject(s)
Adrenal Cortex , Hypothalamo-Hypophyseal System , Pituitary-Adrenal System , Adrenal Glands , Adrenocorticotropic Hormone , Animals , Animals, Newborn , Dogs
20.
Arch Virol ; 166(3): 929-933, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33492522

ABSTRACT

This is the first study of respiratory infections in Córdoba, Argentina, caused by endemic human coronavirus (HCoV)-OC43 and HCOV-229E, which circulated during 2011-2012 at a 3% rate, either as single or multiple infections. They were detected mainly in children, but HCoV-229E was also found in adults. HCoV-229E was detected in five out of 631 samples (0.8%), and HCoV-OC43 was found in 14 out of 631 (2.2%) samples. Clinical manifestations ranged from fever to respiratory distress, and a significant association of HCoV-229E with asthma was observed. Further studies and surveillance are needed to provide better clinical insights, early diagnosis, and medical care of patients, as well as to contribute to epidemiology modeling and prevention.


Subject(s)
Common Cold/epidemiology , Coronavirus 229E, Human/isolation & purification , Coronavirus Infections/epidemiology , Coronavirus OC43, Human/isolation & purification , Adolescent , Adult , Aged , Argentina , Child , Child, Preschool , Common Cold/virology , Coronavirus 229E, Human/genetics , Coronavirus Infections/virology , Coronavirus OC43, Human/genetics , Cross-Sectional Studies , Humans , Infant , Middle Aged , Retrospective Studies , Seasons , Young Adult
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