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1.
Acta Neuropsychiatr ; 36(2): 109-117, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36847240

RESUMEN

OBJECTIVE: Cocaine is a highly addictive psychostimulant that affects synaptic activity with structural and functional adaptations of neurons. The transmembrane synaptic vesicle glycoprotein 2A (SV2A) of pre-synaptic vesicles is commonly used to measure synaptic density, as a novel approach to the detection of synaptic changes. We do not know if a single dose of cocaine suffices to affect pre-synaptic SV2A density, especially during adolescence when synapses undergo intense maturation. Here, we explored potential changes of pre-synaptic SV2A density in target brain areas associated with the cocaine-induced boost of dopaminergic neurotransmission, specifically testing if the effects would last after the return of dopamine levels to baseline. METHODS: We administered cocaine (20 mg/kg i.p.) or saline to rats in early adolescence, tested their activity levels and removed the brains 1 hour and 7 days after injection. To evaluate immediate and lasting effects, we did autoradiography with [3H]UCB-J, a specific tracer for SV2A, in medial prefrontal cortex, striatum, nucleus accumbens, amygdala, and dorsal and ventral areas of hippocampus. We also measured the striatal binding of [3H]GBR-12935 to test cocaine's occupancy of the dopamine transporter at both times of study. RESULTS: We found a significant increase of [3H]UCB-J binding in the dorsal and ventral sections of hippocampus 7 days after the cocaine administration compared to saline-injected rats, but no differences 1 hour after the injection. The [3H]GBR-12935 binding remained unchanged at both times. CONCLUSION: Cocaine provoked lasting changes of hippocampal synaptic SV2A density after a single exposure during adolescence.


Asunto(s)
Cocaína , Hipocampo , Glicoproteínas de Membrana , Animales , Ratas , Amígdala del Cerebelo/efectos de los fármacos , Amígdala del Cerebelo/metabolismo , Encéfalo/metabolismo , Cocaína/metabolismo , Cocaína/farmacología , Cuerpo Estriado , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Tomografía de Emisión de Positrones , Glicoproteínas de Membrana/efectos de los fármacos , Glicoproteínas de Membrana/metabolismo , Proteínas del Tejido Nervioso/efectos de los fármacos , Proteínas del Tejido Nervioso/metabolismo
2.
Front Physiol ; 14: 1145047, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37265839

RESUMEN

The conversion of fibroblasts into myogenic cells is a powerful tool to both develop and test therapeutic strategies and to perform in-depth investigations of neuromuscular disorders, avoiding the need for muscle biopsies. We developed an easy, reproducible, and high-efficiency lentivirus-mediated transdifferentiation protocol, that can be used to convert healthy donor fibroblasts and a promising new cellular model, urinary stem cells (USCs), into myoblasts, that can be further differentiated into multinucleated myotubes in vitro. Transcriptome and proteome profiling of specific muscle markers (desmin, myosin, dystrophin) was performed to characterize both the myoblasts and myotubes derived from each cell type and to test the transdifferentiation-inducing capacity of MYOD1 in fibroblasts and USCs. Specifically, the Duchenne muscular dystrophy (DMD) transcripts and proteins, including both the full-length Dp427 and the short Dp71 isoform, were evaluated. The protocol was firstly developed in healthy donor fibroblasts and USCs and then used to convert DMD patients' fibroblasts, with the aim of testing the efficacy of an antisense drug in vitro. Technical issues, limitations, and problems are explained and discussed. We demonstrate that MyoD-induced-fibroblasts and USCs are a useful in vitro model of myogenic cells to investigate possible therapies for neuromuscular diseases.

3.
Int J Mol Sci ; 24(6)2023 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-36982290

RESUMEN

Duchenne muscular dystrophy (DMD) is a rare neuromuscular disease caused by pathogenic variations in the DMD gene. There is a need for robust DMD biomarkers for diagnostic screening and to aid therapy monitoring. Creatine kinase, to date, is the only routinely used blood biomarker for DMD, although it lacks specificity and does not correlate with disease severity. To fill this critical gap, we present here novel data about dystrophin protein fragments detected in human plasma by a suspension bead immunoassay using two validated anti-dystrophin-specific antibodies. Using both antibodies, a reduction of the dystrophin signal is detected in a small cohort of plasma samples from DMD patients when compared to healthy controls, female carriers, and other neuromuscular diseases. We also demonstrate the detection of dystrophin protein by an antibody-independent method using targeted liquid chromatography mass spectrometry. This last assay detects three different dystrophin peptides in all healthy individuals analysed and supports our finding that dystrophin protein is detectable in plasma. The results of our proof-of-concept study encourage further studies in larger sample cohorts to investigate the value of dystrophin protein as a low invasive blood biomarker for diagnostic screening and clinical monitoring of DMD.


Asunto(s)
Distrofia Muscular de Duchenne , Proteómica , Femenino , Humanos , Anticuerpos , Biomarcadores , Cromatografía Liquida , Distrofia Muscular de Duchenne/genética , Proteómica/métodos , Distrofina/sangre
4.
Cancer Metastasis Rev ; 42(1): 197-215, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36757577

RESUMEN

The biological complexity of cancer represents a tremendous clinical challenge, resulting in the frequent failure of current treatment protocols. In the rapidly evolving scenario of a growing tumor, anticancer treatments impose a drastic perturbation not only to cancer cells but also to the tumor microenvironment, killing a portion of the cells and inducing a massive stress response in the survivors. Consequently, treatments can act as a double-edged sword by inducing a temporary response while laying the ground for therapy resistance and subsequent disease progression. Cancer cell dormancy (or quiescence) is a central theme in tumor evolution, being tightly linked to the tumor's ability to survive cytotoxic challenges, metastasize, and resist immune-mediated attack. Accordingly, quiescent cancer cells (QCCs) have been detected in virtually all the stages of tumor development. In recent years, an increasing number of studies have focused on the characterization of quiescent/therapy resistant cancer cells, unveiling QCCs core transcriptional programs, metabolic plasticity, and mechanisms of immune escape. At the same time, our partial understanding of tumor quiescence reflects the difficulty to identify stable QCCs biomarkers/therapeutic targets and to control cancer dormancy in clinical settings. This review focuses on recent discoveries in the interrelated fields of dormancy, stemness, and therapy resistance, discussing experimental evidences in the frame of a nonlinear dynamics approach, and exploring the possibility that tumor quiescence may represent not only a peril but also a potential therapeutic resource.


Asunto(s)
Antineoplásicos , Neoplasias , Humanos , Células Madre Neoplásicas/patología , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Neoplasias/metabolismo , Antineoplásicos/farmacología , Progresión de la Enfermedad , Microambiente Tumoral
5.
Cancers (Basel) ; 14(15)2022 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-35954367

RESUMEN

Lung cancer is the leading cause of cancer death worldwide. Despite significant advances in research and therapy, a dismal 5-year survival rate of only 10-20% urges the development of reliable preclinical models and effective therapeutic tools. Lung cancer is characterized by a high degree of heterogeneity in its histology, a genomic landscape, and response to therapies that has been traditionally difficult to reproduce in preclinical models. However, the advent of three-dimensional culture technologies has opened new perspectives to recapitulate in vitro individualized tumor features and to anticipate treatment efficacy. The generation of lung cancer organoids (LCOs) has encountered greater challenges as compared to organoids derived from other tumors. In the last two years, many efforts have been dedicated to optimizing LCO-based platforms, resulting in improved rates of LCO production, purity, culture timing, and long-term expansion. However, due to the complexity of lung cancer, further advances are required in order to meet clinical needs. Here, we discuss the evolution of LCO technology and the use of LCOs in basic and translational lung cancer research. Although the field of LCOs is still in its infancy, its prospective development will likely lead to new strategies for drug testing and biomarker identification, thus allowing a more personalized therapeutic approach for lung cancer patients.

6.
Ecol Evol ; 12(8): e9155, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35949533

RESUMEN

The processes leading to the emergence of new species are poorly understood in marine plankton, where weak physical barriers and homogeneous environmental conditions limit spatial and ecological segregation. Here, we combine molecular and ecological information from a long-term time series and propose Pseudo-nitzschia allochrona, a new cryptic planktonic diatom, as a possible case of speciation by temporal segregation. The new species differs in several genetic markers (18S, 28S and ITS rDNA fragments and rbcL) from its closest relatives, which are morphologically very similar or identical, and is reproductively isolated from its sibling species P. arenysensis. Data from a long-term plankton time series show P. allochrona invariably occurring in summer-autumn in the Gulf of Naples, where its closely related species P. arenysensis, P. delicatissima, and P. dolorosa are instead found in winter-spring. Temperature and nutrients are the main factors associated with the occurrence of P. allochrona, which could have evolved in sympatry by switching its phenology and occupying a new ecological niche. This case of possible speciation by time shows the relevance of combining ecological time series with molecular information to shed light on the eco-evolutionary dynamics of marine microorganisms.

7.
Intern Emerg Med ; 17(7): 1997-2004, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35930184

RESUMEN

Handgrip strength (HGS), a simple tool for the evaluation of muscular strength, is independently associated with negative prognosis in many diseases. It is unknown whether HGS is prognostically relevant in COVID-19. We evaluated the ability of HGS to predict clinical outcomes in people with COVID-19-related pneumonia. 118 patients (66% men, 63 ± 12 years), consecutively hospitalized to the "Santa Maria" Terni University Hospital for COVID-19-related pneumonia and respiratory failure, underwent HGS measurement (Jamar hand-dynamometer) at ward admission. HGS was normalized to weight2/3 (nHGS) The main end-point was the first occurrence of death and/or endotracheal intubation at 14 days. Twenty-two patients reached the main end-point. In the Kaplan-Meyer analysis, the Log rank test showed significant differences between subjects with lower than mean HGS normalized to weight2/3 (nHGS) (< 1.32 kg/Kg2/3) vs subjects with higher than mean nHGS. (p = 0.03). In a Cox-proportional hazard model, nHGS inversely predicted the main end-point (hazard ratio, HR = 1.99 each 0.5 kg/Kg2/3 decrease, p = 0.03), independently from age, sex, body mass index, ratio of partial pressure arterial oxygen and fraction of inspired oxygen (PaO2/FiO2 ratio), hypertension, diabetes, estimated glomerular filtration rate and history of previous cardiovascular cardiovascular disease. These two latter also showed independent association with the main end-point (HR 1.30, p = 0.03 and 3.89, p < 0.01, respectively). In conclusion, nHGS measured at hospital admission, independently and inversely predicts the risk of poor outcomes in people with COVID-19-related pneumonia. The evaluation of HGS may be useful in early stratifying the risk of adverse prognosis in COVID-19.


Asunto(s)
COVID-19 , Enfermedades Cardiovasculares , Índice de Masa Corporal , COVID-19/complicaciones , Femenino , Fuerza de la Mano , Hospitalización , Humanos , Masculino , Oxígeno
8.
Front Oncol ; 12: 830873, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35719935

RESUMEN

Chemotherapy is the mainstay for the treatment of non-small cell lung cancer (NSCLC). However, NSCLC cells are either intrinsically chemoresistant or rapidly develop therapy resistance. Cancer stem cells (CSCs) are widely recognized as the cell population responsible for resistance to systemic therapies, but the molecular responses of CSCs to chemotherapeutic agents are largely unknown. We identified the embryonic protein CRIPTO in stem cell-enriched spheroid cultures of adenocarcinoma (AC) and squamous cell carcinoma (SCC) derived from NSCLC surgical specimens. The CRIPTO-positive population had increased clonogenic capacity and expression of stem cell-related factors. Stemness-related properties were also obtained with forced CRIPTO expression, whereas CRIPTO downregulation resulted in cell cycle blockade and CSCs death. Cell populations positive and negative for CRIPTO expression were interconvertible, and interfering with their reciprocal equilibrium resulted in altered homeostasis of cell expansion both in spheroid cultures and in tumor xenografts. Chemotherapy treatment of NSCLC cells resulted in reduction of cell number followed by increased CRIPTO expression and selective survival of CRIPTO-positive cells. In NSCLC tumor xenografts, chemotherapeutic agents induced partial cell death and tumor stabilization followed by CRIPTO overexpression and tumor progression. Altogether, these findings indicate CRIPTO as a marker of lung CSCs possibly implicated in cancer cell plasticity and post-chemotherapy tumor progression.

9.
Front Neurosci ; 16: 864514, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35573314

RESUMEN

In recent years, the field of neuroimaging dramatically moved forward by means of the expeditious development of specific radioligands of novel targets. Among these targets, the synaptic vesicle glycoprotein 2A (SV2A) is a transmembrane protein of synaptic vesicles, present in all synaptic terminals, irrespective of neurotransmitter content. It is involved in key functions of neurons, focused on the regulation of neurotransmitter release. The ubiquitous expression in gray matter regions of the brain is the basis of its candidacy as a marker of synaptic density. Following the development of molecules derived from the structure of the anti-epileptic drug levetiracetam, which selectively binds to SV2A, several radiolabeled markers have been synthetized to allow the study of SV2A distribution with positron emission tomography (PET). These radioligands permit the evaluation of in vivo changes of SV2A distribution held to be a potential measure of synaptic density in physiological and pathological conditions. The use of SV2A as a biomarker of synaptic density raises important questions. Despite numerous studies over the last decades, the biological function and the expressional properties of SV2A remain poorly understood. Some functions of SV2A were claimed, but have not been fully elucidated. While the expression of SV2A is ubiquitous, stronger associations between SV2A and Υ amino butyric acid (GABA)-ergic rather than glutamatergic synapses were observed in some brain structures. A further issue is the unclear interaction between SV2A and its tracers, which reflects a need to clarify what really is detected with neuroimaging tools. Here, we summarize the current knowledge of the SV2A protein and we discuss uncertain aspects of SV2A biology and physiology. As SV2A expression is ubiquitous, but likely more strongly related to a certain type of neurotransmission in particular circumstances, a more extensive knowledge of the protein would greatly facilitate the analysis and interpretation of neuroimaging results by allowing the evaluation not only of an increase or decrease of the protein level, but also of the type of neurotransmission involved.

10.
PLoS One ; 17(3): e0265469, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35358230

RESUMEN

We designed a novel strategy to define codon usage bias (CUB) in 6 specific small cohorts of human genes. We calculated codon usage (CU) values in 29 non-disease-causing (NDC) and 31 disease-causing (DC) human genes which are highly expressed in 3 distinct tissues, kidney, muscle, and skin. We applied our strategy to the same selected genes annotated in 15 mammalian species. We obtained CUB hierarchical clusters for each gene cohort which showed tissue-specific and disease-specific CUB fingerprints. We showed that DC genes (especially those expressed in muscle) display a low CUB, well recognizable in codon hierarchical clustering. We defined the extremely biased codons as "zero codons" and found that their number is significantly higher in all DC genes, all tissues, and that this trend is conserved across mammals. Based on this calculation in different gene cohorts, we identified 5 codons which are more differentially used across genes and mammals, underlining that some genes have favorite synonymous codons in use. Since of the muscle genes clear clusters, and, among these, dystrophin gene surprisingly does not show any "zero codon" we adopted a novel approach to study CUB, we called "mapping-on-codons". We positioned 2828 dystrophin missense and nonsense pathogenic variations on their respective codon, highlighting that its frequency and occurrence is not dependent on the CU values. We conclude our strategy consents to identify a hierarchical clustering of CU values in a gene cohort-specific fingerprints, with recognizable trend across mammals. In DC muscle genes also a disease-related fingerprint can be observed, allowing discrimination between DC and NDC genes. We propose that using our strategy which studies CU in specific gene cohorts, as rare disease genes, and tissue specific genes, may provide novel information about the CUB role in human and medical genetics, with implications on synonymous variations interpretation and codon optimization algorithms.


Asunto(s)
Uso de Codones , Magnoliopsida , Animales , Análisis por Conglomerados , Codón/genética , Distrofina/genética , Humanos , Magnoliopsida/genética , Mamíferos/genética , Enfermedades Raras/genética , Selección Genética
11.
HGG Adv ; 3(1): 100054, 2022 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-35047845

RESUMEN

Urinary stem cells (USCs) are a non-invasive, simple, and affordable cell source to study human diseases. Here we show that USCs are a versatile tool for studying Duchenne muscular dystrophy (DMD), since they are able to address RNA signatures and atypical mutation identification. Gene expression profiling of DMD individuals' USCs revealed a profound deregulation of inflammation, muscle development, and metabolic pathways that mirrors the known transcriptional landscape of DMD muscle and worsens following USCs' myogenic transformation. This pathogenic transcription signature was reverted by an exon-skipping corrective approach, suggesting the utility of USCs in monitoring DMD antisense therapy. The full DMD transcript profile performed in USCs from three undiagnosed DMD individuals addressed three splicing abnormalities, which were decrypted and confirmed as pathogenic variations by whole-genome sequencing (WGS). This combined genomic approach allowed the identification of three atypical and complex DMD mutations due to a deep intronic variation and two large inversions, respectively. All three mutations affect DMD gene splicing and cause a lack of dystrophin protein production, and one of these also generates unique fusion genes and transcripts. Further characterization of USCs using a novel cell-sorting technology (Celector) highlighted cell-type variability and the representation of cell-specific DMD isoforms. Our comprehensive approach to USCs unraveled RNA, DNA, and cell-specific features and demonstrated that USCs are a robust tool for studying and diagnosing DMD.

12.
Int J Infect Dis ; 116: 154-156, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34986404

RESUMEN

Vaccine-induced immune thrombotic thrombocytopenia (VITT) has emerged as a rare side effect of adenoviral vector-based vaccines against coronavirus disease 2019 (COVID-19), and is most frequently reported after use of the Vaxzevria (AstraZeneca) vaccine. This report describes a case of severe thrombocytopenia associated with massive pulmonary embolism and portal vein thrombosis occurring 13 days after the administration of the single-dose adenoviral vector-based vaccine Ad26.COV2.S (Janssen Vaccines). Based on early clinical suspicion, the patient quickly received treatment with corticosteroids and intravenous immunoglobulin, followed by a rapid increase in platelet count that allowed timely administration of full-dose anticoagulation. Treatment with intravenous immunoglobulin, however, could mask the ability of anti-platelet factor 4-heparin antibodies to bind and activate platelets in the presence of heparin, leading to false-negative results on the immunoassay functional test. Therefore, if VITT is suspected, blood samples for diagnostic confirmation should be collected prior to any treatment to improve diagnostic performance.


Asunto(s)
COVID-19 , Embolia Pulmonar , Trombocitopenia , Vacunas , Ad26COVS1 , Vacunas contra la COVID-19/efectos adversos , Humanos , Embolia Pulmonar/diagnóstico , Embolia Pulmonar/tratamiento farmacológico , Embolia Pulmonar/etiología , SARS-CoV-2 , Trombocitopenia/diagnóstico , Trombocitopenia/etiología , Vacunación/efectos adversos
13.
Front Physiol ; 12: 716471, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34744760

RESUMEN

Background: Neuromuscular disorders (NMDs) are a heterogeneous group of genetic diseases, caused by mutations in genes involved in spinal cord, peripheral nerve, neuromuscular junction, and muscle functions. To advance the knowledge of the pathological mechanisms underlying NMDs and to eventually identify new potential drugs paving the way for personalized medicine, limitations regarding the availability of neuromuscular disease-related biological samples, rarely accessible from patients, are a major challenge. Aim: We characterized urinary stem cells (USCs) by in-depth transcriptome and protein profiling to evaluate whether this easily accessible source of patient-derived cells is suitable to study neuromuscular genetic diseases, focusing especially on those currently involved in clinical trials. Methods: The global transcriptomics of either native or MyoD transformed USCs obtained from control individuals was performed by RNA-seq. The expression of 610 genes belonging to 16 groups of disorders (http://www.musclegenetable.fr/) whose mutations cause neuromuscular diseases, was investigated on the RNA-seq output. In addition, protein expression of 11 genes related to NMDs including COL6A, EMD, LMNA, SMN, UBA1, DYNC1H1, SOD1, C9orf72, DYSF, DAG1, and HTT was analyzed in native USCs by immunofluorescence and/or Western blot (WB). Results: RNA-seq profile of control USCs shows that 571 out of 610 genes known to be involved in NMDs, are expressed in USCs. Interestingly, the expression levels of the majority of NMD genes remain unmodified following USCs MyoD transformation. Most genes involved in the pathogenesis of all 16 groups of NMDs are well represented except for channelopathies and malignant hyperthermia related genes. All tested proteins showed high expression values, suggesting consistency between transcription and protein representation in USCs. Conclusion: Our data suggest that USCs are human cells, obtainable by non-invasive means, which might be used as a patient-specific cell model to study neuromuscular disease-causing genes and that they can be likely adopted for a variety of in vitro functional studies such as mutation characterization, pathway identification, and drug screening.

14.
Clin Infect Pract ; 12: 100096, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34490417

RESUMEN

BACKGROUND: Management of immunocompromised COVID-19 patients is the object of current debate. Accumulating evidence suggest that treatment with high-titer COVID-19 convalescent plasma (CCP) may be effective in this characteristic clinical scenario. CASE REPORT: A 52-years old immunocompromised female patient, previously treated with rituximab for low grade B-cell lymphoma, showed prolonged SARS-CoV-2 shedding and a long-term course of signs of severe COVID-19. A first cycle of treatment with remdesivir, a nucleotide analogue prodrug effective in inhibiting SARS-CoV-2 replication, did not provide fully and sustained clinical remission. A second hospitalization was deemed necessary after 10 days from the first hospital discharge due to recrudescence of symptoms of severe COVID-19 and the evidence of bilateral interstitial pneumonia at the chest-CT scan. Clinical and radiological findings completely disappeared after CCP administration. The viral culture confirmed the absence of SARS-CoV-2-related cytopathic effect. The clinical evaluation, performed two months after hospital discharge, was unremarkable. RESULTS: Findings from our case report suggest that the host T-cell specific response to SARS-CoV-2 is not sufficient to reduce viral load in the absence of neutralizing antibodies. Acquired immune antibodies and/or related components passively infused with CCP might help in boosting the plasma recipient response to the virus and promoting complete viral clearance. CONCLUSIONS: Independently from negative results in immunocompetent individuals, the potential effectiveness of CCP infusion in selected cohorts of patients with primary or secondary impaired immune response should be tested. Further research about mechanisms of host response in immunocompromised patients with SARS-CoV-2 infection is required.

15.
Front Physiol ; 12: 678974, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34305639

RESUMEN

Duchenne muscular dystrophy (DMD) is a rare genetic disease due to dystrophin gene mutations which cause progressive weakness and muscle wasting. Circadian rhythm coordinates biological processes with the 24-h cycle and it plays a key role in maintaining muscle functions, both in animal models and in humans. We explored expression profiles of circadian circuit master genes both in Duchenne muscular dystrophy skeletal muscle and in its animal model, the mdx mouse. We designed a customized, mouse-specific Fluidic-Card-TaqMan-based assay (Fluid-CIRC) containing thirty-two genes related to circadian rhythm and muscle regeneration and analyzed gastrocnemius and tibialis anterior muscles from both unexercised and exercised mdx mice. Based on this first analysis, we prioritized the 7 most deregulated genes in mdx mice and tested their expression in skeletal muscle biopsies from 10 Duchenne patients. We found that CSNK1E, SIRT1, and MYOG are upregulated in DMD patient biopsies, consistent with the mdx data. We also demonstrated that their proteins are detectable and measurable in the DMD patients' plasma. We suggest that CSNK1E, SIRT1, and MYOG might represent exploratory circadian biomarkers in DMD.

16.
Viruses ; 13(6)2021 05 22.
Artículo en Inglés | MEDLINE | ID: mdl-34067349

RESUMEN

Europe is experiencing a third wave of COVID-19 due to the spread of highly transmissible SARS-CoV-2 variants. A number of positive and negative factors constantly shape the rates of COVID-19 infections, hospitalization, and mortality. Among these factors, the rise in increasingly transmissible variants on one side and the effect of vaccinations on the other side create a picture deeply different from that of the first pandemic wave. Starting from the observation that in several European countries the number of COVID-19 infections in the second and third pandemic wave increased without a proportional rise in disease severity and mortality, we hypothesize the existence of an additional factor influencing SARS-CoV-2 dynamics. This factor consists of an immune defence against severe COVID-19, provided by SARS-CoV-2-specific T cells progressively developing upon natural exposure to low virus doses present in populated environments. As suggested by recent studies, low-dose viral particles entering the respiratory and intestinal tracts may be able to induce T cell memory in the absence of inflammation, potentially resulting in different degrees of immunization. In this scenario, non-pharmaceutical interventions would play a double role, one in the short term by reducing the detrimental spreading of SARS-CoV-2 particles, and one in the long term by allowing the development of a widespread (although heterogeneous and uncontrollable) form of immune protection.


Asunto(s)
COVID-19/inmunología , SARS-CoV-2/inmunología , Linfocitos T/inmunología , COVID-19/prevención & control , Relación Dosis-Respuesta Inmunológica , Exposición a Riesgos Ambientales , Humanos , Memoria Inmunológica
17.
Neuromuscul Disord ; 31(6): 479-488, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33773883

RESUMEN

The aim was to assess 3-year longitudinal data using 6MWT in 26 ambulant boys affected by DMD carrying nonsense mutations and to compare their results to other small mutations. We also wished to establish, within the nonsense mutations group, patterns of change according to several variables. Patients with nonsense mutations were categorized according to the stop codon type newly created by the mutation and also including the adjacent 5' (upstream) and 3' (downstream) nucleotides. No significant difference was found between nonsense mutations and other small mutations (p > 0.05) on the 6MWT. Within the nonsense mutations group, there was no difference in 6MWT when the patients were subdivided according to: Type of stop codon, frame status of exons involved, protein domain affected. In contrast, there was a difference when the stop codon together with the 3' adjacent nucleotide ("stop+4 model") was considered (p < 0.05) with patients with stop codon TGA and 3' adjacent nucleotide G (TGAG) having a more rapid decline. Our finding suggest that the stop+4 model may help in predicting functional changes. This data will be useful at the time of interpreting the long term follow up of patients treated with Ataluren that are becoming increasingly available.


Asunto(s)
Codón sin Sentido/genética , Distrofia Muscular de Duchenne/genética , Mutación/genética , Prueba de Paso , Bélgica , Niño , Preescolar , Distrofina/genética , Exones , Humanos , Italia , Estudios Longitudinales , Masculino , Distrofia Muscular de Duchenne/fisiopatología , Oxadiazoles
18.
J Clin Med ; 10(4)2021 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-33671409

RESUMEN

Duchenne muscular dystrophy (DMD) is the most common childhood muscular dystrophy affecting ~1:5000 live male births. Following the identification of pathogenic variations in the dystrophin gene in 1986, the underlining genotype/phenotype correlations emerged and the role of the dystrophin protein was elucidated in skeletal, smooth, and cardiac muscles, as well as in the brain. When the dystrophin protein is absent or quantitatively or qualitatively modified, the muscle cannot sustain the stress of repeated contractions. Dystrophin acts as a bridging and anchoring protein between the sarcomere and the sarcolemma, and its absence or reduction leads to severe muscle damage that eventually cannot be repaired, with its ultimate substitution by connective tissue and fat. The advances of an understanding of the molecular pathways affected in DMD have led to the development of many therapeutic strategies that tackle different aspects of disease etiopathogenesis, which have recently led to the first successful approved orphan drugs for this condition. The therapeutic advances in this field have progressed exponentially, with second-generation drugs now entering in clinical trials as gene therapy, potentially providing a further effective approach to the condition.

19.
Neurol Genet ; 7(1): e536, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33376799

RESUMEN

OBJECTIVE: Genetic diagnosis and mutation identification are now compulsory for Duchenne (DMD) and Becker muscular dystrophies (BMD), which are due to dystrophin (DMD) gene mutations, either for disease prevention or personalized therapies. To evaluate the ethnic-related genetic assortments of DMD mutations, which may impact on DMD genetic diagnosis pipelines, we studied 328 patients with DMD and BMD from non-European countries. METHODS: We performed a full DMD mutation detection in 328 patients from 10 Eastern European countries (Poland, Hungary, Lithuania, Romania, Serbia, Croatia, Bosnia, Bulgaria, Ukraine, and Russia) and 2 non-European countries (Cyprus and Algeria). We used both conventional methods (multiplex ligation-dependent probe amplification [MLPA] followed by gene-specific sequencing) and whole-exome sequencing (WES) as a pivotal study ran in 28 patients where DMD mutations were already identified by standard techniques. WES output was also interrogated for DMD gene modifiers. RESULTS: We identified DMD gene mutations in 222 male patients. We identified a remarkable allele heterogeneity among different populations with a mutation landscape often country specific. We also showed that WES is effective for picking up all DMD deletions and small mutations and its adoption could allow a detection rate close to 90% of all occurring mutations. Gene modifiers haplotypes were identified with some ethnic-specific configurations. CONCLUSIONS: Our data provide unreported mutation landscapes in different countries, suggesting that ethnicity may orient genetic diagnosis flowchart, which can be adjusted depending on the mutation type frequency, with impact in drug eligibility.

20.
Front Oncol ; 10: 592891, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33194755

RESUMEN

Severe coronavirus disease 2019 (COVID-19) causes an uncontrolled activation of the innate immune response, resulting in acute respiratory distress syndrome and systemic inflammation. The effects of COVID-19-induced inflammation on cancer cells and their microenvironment are yet to be elucidated. Here, we formulate the hypothesis that COVID-19-associated inflammation may generate a microenvironment favorable to tumor cell proliferation and particularly to the reawakening of dormant cancer cells (DCCs). DCCs often survive treatment of primary tumors and populate premetastatic niches in the lungs and other organs, retaining the potential for metastatic outgrowth. DCCs reawakening may be promoted by several events associated to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, including activation of neutrophils and monocytes/macrophages, lymphopenia and an uncontrolled production of pro-inflammatory cytokines. Among pro-inflammatory factors produced during COVID-19, neutrophil extracellular traps (NETs) released by activated neutrophils have been specifically shown to activate premetastatic cancer cells disseminated in the lungs, suggesting they may be involved in DCCs reawakening in COVID-19 patients. If confirmed by further studies, the links between COVID-19, DCCs reactivation and tumor relapse may support the use of specific anti-inflammatory and anti-metastatic therapies in patients with COVID-19 and an active or previous cancer.

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