Profile of Bacterial Infections in COVID-19 Patients: Antimicrobial Resistance in the Time of SARS-CoV-2

SIMPLE SUMMARY: Since the beginning of COVID-19 pandemic, no specific drugs have been available to treat the SARS-CoV-2 infection, therefore antibiotics have been often used both for prophylactic and therapeutic purposes. Their wide use, though, is known to contribute to the emergence of antimicrobial resistance. Aiming at evaluating the impact of the COVID-19 pandemic on the distribution and characteristics of bacterial infections, and on the frequency of antimicrobial resistance, we investigated the microbial strains identified through laboratory tests on clinical specimens from COVID-19 and non-COVID-19 patients accessing an Italian tertiary hospital over nearly one year. We highlighted that COVID+ patients bore a significantly higher number of bacterial species. Eight out of the 100 species identified were isolated exclusively from COVID+ and most of them are known to establish infections only in immunocompromised patients. Resistance to every tested antibiotic was seen in 8.3% of the isolates with a correlation with the positivity to COVID, but neither all COVID+ or COVID− isolates showed characteristic responses to the tested antibiotics. The predicted increase of antibiotic resistance is not observable yet, but the higher frequency of multi-resistant COVID+ isolates suggests that it is actually occurring, further calling for the definition of alternative treatments of COVID-19 infections. ABSTRACT: The global onset of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus infections happened suddenly, hence imposing a rapid definition of effective therapeutic approaches. Antibiotics were included among the prophylactic agents because of both the similarity between SARS-CoV-2 and atypical pneumonia symptoms, and the immune-modulating and anti-inflammatory properties of such drugs. Although, this approach could exacerbate the emergence of antimicrobial resistance. To evaluate the impact of the COVID-19 pandemic on the spread and characteristics of bacterial infections, as well as on the frequency of antimicrobial resistance, we investigated and compared clinical bacterial strains isolated in an Italian hospital from COVID-19 patients and non-COVID-19 patients during and before the COVID-19 outbreak. Data clearly indicate the impact of the COVID-19 pandemic on bacterial infections: not only some bacterial species were found in either COVID-19 positive or in COVID-19 negative patients, but isolates from COVID-19 patients also showed higher levels of antimicrobial resistance. Nevertheless, despite some bacterial species were isolated only before or over the pandemic, no differences were observed among the antimicrobial resistance levels. Overall, these results recapitulate the current situation of microbial infections and could also provide an overview of the impact of COVID-19 on bacterial pathogens spread and resistance

Mutant p53 proteins counteract autophagic mechanism sensitizing cancer cells to mTOR inhibition

Mutations in TP53 gene play a pivotal role in tumorigenesis and cancer development. Here, we report that gain-of-function mutant p53 proteins inhibit the autophagic pathway favoring antiapoptotic effects as well as proliferation of pancreas and breast cancer cells. We found that mutant p53 significantly counteracts the formation of autophagic vesicles and their fusion with lysosomes throughout the repression of some key autophagy-related proteins and enzymes as BECN1 (and P-BECN1), DRAM1, ATG12, SESN1/2 and P-AMPK with the concomitant stimulation of mTOR signaling. As a paradigm of this mechanism, we show that atg12 gene repression was mediated by the recruitment of the p50 NF-\u3baB/mutant p53 protein complex onto the atg12 promoter. Either mutant p53 or p50 NF-\u3baB depletion downregulates atg12 gene expression. We further correlated the low expression levels of autophagic genes (atg12, becn1, sesn1, and dram1) with a reduced relapse free survival (RFS) and distant metastasis free survival (DMFS) of breast cancer patients carrying TP53 gene mutations conferring a prognostic value to this mutant p53-and autophagy-related signature. Interestingly, the mutant p53-driven mTOR stimulation sensitized cancer cells to the treatment with the mTOR inhibitor everolimus. All these results reveal a novel mechanism through which mutant p53 proteins promote cancer cell proliferation with the concomitant inhibition of autophagy

Alternating Hemiplegia of Childhood in a Child Harboring a Novel TBC1D24 Mutation: Case Report and Literature Review

AbstractAlternating Hemiplegia of Childhood (AHC) is a rare neurological disease characterized by early-onset recurrent paroxysmal events and persistent neurological deficits. TBC1D24 gene variants have been associated with a phenotypic spectrum having epilepsy as the main clinical manifestation. Herein, we report the case of a child affected by developmental delay, polymorphic seizures, and nonepileptic episodes characterized by hemiplegia or bilateral plegia, pallor, hypotonia, and dystonic postures without loss of consciousness that resolved with sleep. Noteworthy, the patient fulfills all the diagnostic criteria for AHC. An epilepsy gene panel revealed a novel TBC1D24 mutation. This variant may be considered a PM5, according to the American College of Medical Genetics and Genomics guidelines. TBC1D24 gene variants are associated with various clinical features, and increasing data confirms the association with permanent and paroxysmal movement disorders. Our report suggests that the TBC1D24 molecular analysis could be considered in the diagnostic workup of AHC patients

Cardiac autonomic control in Rett syndrome: Insights from heart rate variability analysis

Rett syndrome (RTT) is a rare and severe neurological disorder mainly affecting females, usually linked to methyl-CpG-binding protein 2 (MECP2) gene mutations. Manifestations of RTT typically include loss of purposeful hand skills, gait and motor abnormalities, loss of spoken language, stereotypic hand movements, epilepsy, and autonomic dysfunction. Patients with RTT have a higher incidence of sudden death than the general population. Literature data indicate an uncoupling between measures of breathing and heart rate control that could offer insight into the mechanisms that lead to greater vulnerability to sudden death. Understanding the neural mechanisms of autonomic dysfunction and its correlation with sudden death is essential for patient care. Experimental evidence for increased sympathetic or reduced vagal modulation to the heart has spurred efforts to develop quantitative markers of cardiac autonomic profile. Heart rate variability (HRV) has emerged as a valuable non-invasive test to estimate the modulation of sympathetic and parasympathetic branches of the autonomic nervous system (ANS) to the heart. This review aims to provide an overview of the current knowledge on autonomic dysfunction and, in particular, to assess whether HRV parameters can help unravel patterns of cardiac autonomic dysregulation in patients with RTT. Literature data show reduced global HRV (total spectral power and R-R mean) and a shifted sympatho-vagal balance toward sympathetic predominance and vagal withdrawal in patients with RTT compared to controls. In addition, correlations between HRV and genotype and phenotype features or neurochemical changes were investigated. The data reported in this review suggest an important impairment in sympatho-vagal balance, supporting possible future research scenarios, targeting ANS

Antioxidant Mechanisms and ROS-Related MicroRNAs in Cancer Stem Cells

Increasing evidence indicates that most of the tumors are sustained by a distinct population of cancer stem cells (CSCs), which are responsible for growth, metastasis, invasion, and recurrence. CSCs are typically characterized by self-renewal, the key biological process allowing continuous tumor proliferation, as well as by differentiation potential, which leads to the formation of the bulk of the tumor mass. CSCs have several advantages over the differentiated cancer cell populations, including the resistance to radio- and chemotherapy, and their gene-expression programs have been shown to correlate with poor clinical outcome, further supporting the relevance of stemness properties in cancer. The observation that CSCs possess enhanced mechanisms of protection from reactive oxygen species (ROS) induced stress and a different metabolism from the differentiated part of the tumor has paved the way to develop drugs targeting CSC specific signaling. In this review, we describe the role of ROS and of ROS-related microRNAs in the establishment and maintenance of self-renewal and differentiation capacities of CSCs

Gain-of-function mutant p53 enhances mitochondrial ROS through the inhibition of PGC-1\u3b1/UCP2 axis in cancer cells

Mutations in the TP53 gene occur in over 50% of the human cancers and most of them are missense mutations that result in the expression of mutant forms of p53. In addition, p53 mutated proteins acquire new biological properties referred as gain-of-function (GOF) that contribute to the induction and maintenance of cancer. Reactive oxygen species (ROS) are radicals, ions or molecules highly reactive that are produced as an inevitable byproduct of mitochondrial oxidative phosphorylation. ROS can act as second messengers in cellular signaling in human cancer and are implicated in a plethora of biological events addressed to sustain each aspect of its progression. Uncoupling protein 2 (UCP2) is located in the mitochondrial inner membrane and plays an essential role is critical in energy regulation and in the maintenance of cellular ROS homeostasis by limiting the production of mitochondrial superoxide. We have investigated the molecular mechanisms by which mutant p53 regulates the redox status in cancer cells and its role in sustaining cancer progression and chemoresistance. We found that mutant p53 proteins, contrarily to wild type p53, enhance mitochondrial ROS in cancer cells which are crucial mediators of their oncogenic activity leading: i) cancer cell proliferation, ii) inhibition of apoptosis, and iii) chemoresistance. Importantly, we unveiled that mutant p53 inhibits SESN/AMPK-\u3b1 interaction leading an inhibition of AMPK phosphorylation. Consequently to the deregulation of AMPK signaling by mutant p53, but not by wild type p53, the expression of its effector PGC-1\u3b1 was also affected, driving a reduction of UCP2 expression and an increase of mitochondrial superoxide. These data reveal a novel mechanism by which mutant p53 sustains tumor progression and lightened on the importance that plays the redox cellular status in the tumors carrying oncogenic mutant p53 proteins

REDOX SIGNALING HYPERSENSITIVITY DISTINGUISHES CHRONIC LYMPHOCYTIC LEUKEMIA PATIENTS WITH FAVORABLE PROGNOSIS

Background. Chronic lymphocytic leukemia (CLL) patients exhibit a variable clinical course, with some patients having indolent disease and others experiencing a more accelerated course, treatment resistance and dismal outcome. The B-cell receptor (BCR) signaling is a key determinant of heterogeneous clinical behavior of CLL and is a target for therapeutic interventions. Endogenously produced H2O2 is thought to fine tune the level of BCR signaling by reversibly inhibiting phosphatases. However, relatively little is known about how CLL cells sense and respond to such redox cues. Aims. In this study, we used phospho-specific flow cytometry to compare BCR signaling responses to H2O2 in prognostic groups of CLL patients. Methods. The phosphorylation levels of five proteins downstream of the BCR signaling, namely SYK, NF-\u3baB p65, ERK1/2, p38 and JNK, were analyzed at the single-cell level in 26 CLL cell samples using phospho-specific flow cytometry. Protein phosphorylation was measured in the basal condition and following stimulation with H2O2. Circulating B cells from healthy individuals were analyzed as controls. The two-sample Wilcoxon\u2019s rank sum test was used to compare protein phosphorylation in groups of patients. Time to first treatment (TTFT) was calculated from the date of diagnosis to the date of initial therapy. TTFT curves estimated using the Kaplan- Meier method for the respective groups of patients were compared using the log-rank test. Results. In CLL cells, stimulation with H2O2 induced a statistically significant increase in phosphorylation of all analyzed signaling proteins with the exception of SYK. Moreover, the extents of responses to H2O2 were significantly higher in CLL than normal B cells for all signaling proteins but SYK. Comparison of H2O2 signaling response in prognostic groups of patients defined by IGHV mutational status, CD38 or ZAP-70 expression, showed that median phosphorylation response of ERK1/2 to H2O2 was significantly higher in the patient subset defined by the mutated IGHV status (M-CLL) (P=0.031). No significant correlations were observed between H2O2 responsiveness of BCR signaling proteins and ZAP-70 or CD38 expression. Kaplan-Meier curves showed statistically significant slower progression (longer time to first treatment, TTFT) in patients with higher p-ERK1/2 and p-NF-\uf06bB p65 responses to H2O2, indicating that lower responsiveness of these signaling proteins to H2O2 correlated with more rapid progression [median TTFT was 41.6 and 115 months for patients with lower and higher NK-\u3baB p65 responsiveness to H2O2, respectively (log-rank test P=0.0011); median TTFT was 38.7 and 117.0 months for patients with lower and higher ERK1/2 responsiveness to H2O2, respectively (log-rank test P=0.0008)] (Figure 1). Interestingly, the ability of H2O2 responsiveness signaling to define prognostic groups is comparable to that of IGHV mutational status (log-rank test P=0.0003). Conclusions. This study reveals that a novel H2O2 signaling response distinguishes a prognostic group of CLL patients with favorable prognosis. Specifically, higher H2O2 responsiveness of ERK1/2 or NF-\u3baB is predictive of longer TTFT, thus highlighting ERK and NF-\u3baB as biologically and clinically relevant signaling nodes in CLL

Sleep Disturbances in Pediatric Craniopharyngioma: A Systematic Review

Craniopharyngiomas are rare brain tumors of the sellar region and are the most common non-neuroepithelial intracerebral neoplasm in children. Despite a low-grade histologic classification, craniopharyngiomas can have a severe clinical course due to hypothalamic involvement. The hypothalamus plays a crucial role in regulating vital functions, and it is a critical component of the sleep-wake regulatory system. This systematic review aims to provide an overview of the current knowledge on sleep disorders in patients with craniopharyngioma to unravel their underlying mechanisms and identify possible therapeutic strategies. A comprehensive electronic literature search of the PubMed/MEDLINE and Scopus databases was conducted in accordance with the PRISMA (R) statement. Extensively published, peer-reviewed articles involving patients with childhood craniopharyngioma and focused on this specific topic were considered eligible for inclusion. Thirty-two articles were included; a high prevalence of excessive daytime sleepiness was reported in CP patients, with wide variability (25-100%) depending on the diagnostic method of detection (25-43% by subjective measures, 50-100% by objective investigations). In particular, secondary narcolepsy was reported in 14-35%, sleep-disordered breathing in 4-46%. Moreover, sleep-wake rhythm dysregulation has been notified, although no prevalence data are available. Possible mechanisms underlying these disorders are discussed, including hypothalamic injury, damage to the suprachiasmatic nucleus, low melatonin levels, hypocretin deficiency, and hypothalamic obesity. The diagnosis and management of sleep disorders and associated comorbidities are challenging. This review summarizes the pathophysiology of sleep disorders in childhood-onset CP and the main treatment options. Finally, a possible diagnostic algorithm in order to accurately identify and treat sleep disorders in these patients is proposed

Correlations between Sleep Features and Iron Status in Children with Neurodevelopmental Disorders: A Cross-Sectional Study

A high prevalence of sleep disturbances has been reported in children with neurodevelopmental disorders (NDDs), such as autism spectrum disorder (ASD), attention deficit hyperactivity disorder (ADHD), and intellectual disability (ID). The etiology of sleep disorders in these children is heterogeneous and, recently, iron deficiency has received increasing attention. This study aims to investigate sleep features in children with NDDs and to explore a possible correlation between serum iron status biomarkers and qualitative features of sleep. We included 4- to 12-year-old children with a diagnosis of ASD, ADHD, or ID and assessed their sleep features through the children's sleep habits questionnaire (CSHQ). Venous blood samples were collected to investigate ferritin, transferrin, and iron levels. The mean CSHQ total score exceeds the cut-off in all groups of children. In the ASD group, the Parasomnias subscale negatively correlated with serum ferritin levels (Rho = 0.354; p = 0.029). Our findings may suggest the existence of an association between iron status, sleep quality, and neurodevelopmental processes. In clinical practice, sleep assessment should be included in the routine assessment for patients with NDDs. Furthermore, a routine assessment of iron status biomarkers should be recommended for children with NDDs who have sleep disturbances