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BACKGROUND: Premature birth is known to affect the newborn's autonomic nervous system (ANS) maturation, with potential short and long-term impact on their neurobehavioral development. The purpose of the study was to investigate the effects of maternal directed singing and speaking on the preterm infants' autonomic nervous system (ANS) maturation as measured by the heart rate variability (HRV) parameters. METHODS: In this multi-center randomized clinical trial, 30 stable preterm infants (m = 29,6 weeks of gestational age), without any abnormalities were randomized into an intervention (16) or a control group (14). HRV was measured weekly, for a total of 80 recordings during hospitalization, as well as before and after each session of singing or speaking. RESULTS: The intervention group showed a significant increase of the percentage value of HRV power in the high frequency range when compared to the control group (p = 0.044). More specifically, the maternal singing significantly increased the high frequency power and decreased the low/high frequency power ratio (p = 0.037). CONCLUSIONS: The preterm infant's vagal activity significantly increased in the intervention group, potentially enhancing their ANS maturation. The effect is specifically evidenced in the singing condition. IMPACT: Maternal singing affects the autonomic nervous system maturation of preterm hospitalized newborns in the NICU. No previous studies investigated how early vocal parental intervention can affect preterm infants developement, throught their autonomic nervous system maturation. Early Vocal Contact as an early intervention involving parents has a positive impact on preterm infant's development and it can be easily implemented in the care of preterm infants. TRIAL REGISTRATION: NCT04759573, retrospectively registered, 17 February 2021.
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Nascimento Prematuro , Canto , Lactente , Feminino , Gravidez , Recém-Nascido , Humanos , Recém-Nascido Prematuro/fisiologia , Sistema Nervoso Autônomo , Idade Gestacional , Frequência Cardíaca/fisiologiaRESUMO
Therapeutic hypothermia (TH) is the standard of care for newborns with moderate to severe hypoxic-ischemic encephalopathy (HIE). Discomfort and pain during treatment are common and may affect the therapeutic efficacy of TH. Opioid sedation and analgesia (SA) are generally used in clinical practice, and fentanyl is one of the most frequently administered drugs. However, although fentanyl's pharmacokinetics (PKs) may be altered by hypothermic treatment, the PK behavior of this opioid drug in cooled newborns with HIE has been poorly investigated. The aim of this phase 1 study protocol (Trial ID: FentanylTH; EUDRACT number: 2020-000836-23) is to evaluate the fentanyl time-concentration profiles of full-term newborns with HIE who have been treated with TH. Newborns undergoing TH receive a standard fentanyl regimen (2 mcg/Kg of fentanyl as a loading dose, followed by a continuous infusion-1 mcg/kg/h-during the 72 h of TH and subsequent rewarming). Fentanyl plasma concentrations before bolus administration, at the end of the loading dose, and 24-48-72-96 h after infusion are measured. The median, maximum, and minimum plasma concentrations, together with drug clearance, are determined. This study will explore the fentanyl time-concentration profiles of cooled, full-term newborns with HIE, thereby helping to optimize the fentanyl SA dosing regimen during TH.
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BACKGROUND: Improvements in perinatal care have substantially decreased mortality rates among preterm infants, yet their neurodevelopmental outcomes and quality of life persist as a pertinent public health concern. Family-centered care has emerged as a holistic philosophy that promotes effective alliances among patients, families, and healthcare providers to improve the quality of care. AIMS: This longitudinal prospective study aims to evaluate the neurodevelopmental outcomes and brain MRI findings in a cohort of preterm newborns admitted to a neonatal intensive care unit (NICU) adopting a family-centered care model. METHODS: Very low birth weight (VLBW) infants admitted to the NICU of Modena between 2015 and 2020 were enrolled. Infants who underwent conventional brain magnetic resonance imaging (MRI) at term-equivalent age were included. Neurodevelopmental follow-up was performed until the age of 24 months by a multidisciplinary team using the Amiel-Tison neurological assessment and the Griffiths Mental Developmental Scales (GMDS-R). Neurodevelopmental outcomes were classified as major sequelae (cerebral palsy, DQ ≤ 70, severe sensory impairment), minor sequelae (minor neurological signs such as clumsiness or DQ between 71 and 85), and normal outcomes (no neurological signs and DQ > 85). Risk factors for severe outcomes were assessed. RESULTS: In total, 49 of the 356 infants (13.8%) died before hospital discharge, and 2 were excluded because of congenital disorders. Of the remaining 305 infants, 222 (72.8%) completed the 24 month follow-up and were included in the study. Neurodevelopmental outcomes were classified as normal (n = 173, 77.9%), minor (n = 34, 15.3%), and major sequelae (n = 15, 6.8%). Among 221 infants undergoing brain MRI, 76 (34.4%) had major lesions (intraventricular hemorrhage, hemorrhagic parenchymal infarction, periventricular leukomalacia, and large cerebellar hemorrhage). In the multivariate regression model, the retinopathy of prematurity (OR 1.8; p value 0.016) and periventricular-intraventricular hemorrhage (OR 5.6; p value < 0.004) were associated with major sequelae. CONCLUSIONS: We reported low rates of severe neurodevelopmental outcomes in VLBW infants born in an Italian NICU with FCC. Identifying the risk factors for severe outcomes can assist in tailoring and optimizing early interventions on an individual basis, both within the NICU and after discharge.
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Sudden unexpected postnatal collapse (SUPC) is a rare event, potentially associated with catastrophic consequences. Since the beginning of the 2000s, therapeutic hypothermia (TH) has been proposed as a treatment for asphyxiated neonates after SUPC. However, only a few studies have reported the outcome of SUPC after TH. The current study presents the long-term neurodevelopmental outcome of four cases of SUPC treated with TH in a single Italian center. Furthermore, we reviewed the previous literature concerning 49 cases of SUPC treated with TH. Among 53 total cases (of whom four occurred in our center), 15 (28.3%) died before discharge from the NICU. A neurodevelopmental follow-up was available only for 21 (55.3%) out of the 38 surviving cases, and seven infants developed neurodevelopmental sequelae. TH should be considered in neonates with asphyxia after SUPC. However, SUPC is a rare event, and there is a lack of comparative clinical data to establish the risk/benefit of TH after SUPC with different degrees of asphyxia. Analysis of large cohorts of newborns with SUPC, whether treated with TH or untreated, are needed in order to better identify infants who should undergo TH.
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In March 2020, the first pandemic caused by a coronavirus was declared by the World Health Organization. Italy was one of the first and most severely affected countries, particularly the northern part of the country. The latest evidence suggests that the virus could have been circulating, at least in Italy, before the first autochthonous SARS-COV-2 case was detected in February 2020. The present study aimed to investigate the presence of antibodies against SARS-CoV-2 in human serum samples collected in the last months of 2019 (September-December) in the Apulia region, Southern Italy. Eight of 455 samples tested proved positive on in-house receptor-binding-domain-based ELISA. Given the month of collection of the positive samples, these findings may indicate early circulation of SARS-CoV-2 in Apulia region in the autumn of 2019. However, it cannot be completely ruled out that the observed sero-reactivity could be an unknown antigen specificity in another virus to which subjects were exposed containing an epitope adventitiously cross-reactive with an epitope of SARS-CoV-2.
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COVID-19 , SARS-CoV-2 , Anticorpos Antivirais , COVID-19/epidemiologia , Epitopos , Humanos , Itália/epidemiologia , PandemiasRESUMO
BACKGROUND: Early parental interventions in the Neonatal Intensive Care Units (NICUs) have beneficial effects on preterm infants' short and long-term outcomes. The aim of this study was to investigate the effects of Early Vocal Contact (EVC)-singing and speaking-on preterm infants' vagal activity and autonomic nervous system (ANS) maturation. METHODS: In this multi-center randomized clinical trial, twenty-four stable preterm infants, born at 25-32 weeks gestational age, were randomized to either the EVC group or control group, where mothers did not interact with the babies but observed their behavior. Heart Rate Variability (HRV) was acquired before intervention (pre-condition), during vocal contact, and after it (post condition). RESULTS: No significant effect of the vocal contact, singing and speaking, was found in HRV when the intervention group was compared to the control group. However, a significant difference between the singing and the pre and post conditions, respectively, preceding and following the singing intervention, was found in the Low and High Frequency power nu, and in the low/high frequency features (p = 0.037). By contrast, no significant effect of the speaking was found. CONCLUSIONS: Maternal singing, but not speaking, enhances preterm infants' vagal activity in the short-term, thus improving the ANS stability. Future analyses will investigate the effect of enhanced vagal activity on short and long-term developmental outcomes of preterm infants in the NICU.
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INTRODUCTION: Therapeutic hypothermia is the standard care for asphyxiated newborns. Discomfort and pain during treatment are common and may affect therapeutic efficacy of hypothermia. Opioid analgosedation is commonly used in the clinical setting, but its effects in the cooled newborns is poorly investigated. OBJECTIVE: The aim of this study was to assess the safety of fentanyl analgosedation during therapeutic hypothermia, by evaluating severe adverse effects and possible correlation with the neurodevelopmental outcome. METHODS: We analyzed asphyxiated newborns treated with hypothermia receiving fentanyl intravenous infusion (years 2013-2018). Severe neurodevelopmental outcome was defined as cerebral palsy or Griffith's developmental quotient <70 or major sensorineural deficit. Severe brain lesions were defined as cortical or/and basal ganglia extensive involvement. RESULTS: Fentanyl cumulative dose was variable (61.7 ± 18.5 µg/kg; range 34.3-120.3 µg/kg) among 45 enrolled patients. Respiratory depression was recorded in 13.3% cases of 30 spontaneously breathing patients. Severe brain lesions and severe neurodevelopmental disability were found in 24.4 and 11.1% of all included cases, respectively. Higher cumulative fentanyl dose was not associated with poor outcome. CONCLUSIONS: Fentanyl treatment during therapeutic hypothermia does not negatively affect the neurodevelopmental outcome, thus on the contrary, it may contribute to ameliorate neuroprotection in the asphyxiated cooled newborns.
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Analgesia , Asfixia Neonatal , Hipotermia Induzida , Hipotermia , Hipóxia-Isquemia Encefálica , Doenças do Recém-Nascido , Recém-Nascido , Humanos , Asfixia Neonatal/complicações , Asfixia Neonatal/terapia , Fentanila , Hipotermia/terapia , Hipóxia-Isquemia Encefálica/terapia , Hipotermia Induzida/efeitos adversos , Doenças do Recém-Nascido/etiologia , Dor/etiologiaRESUMO
INTRODUCTION: Children with late fetal growth restriction (FGR) are at high risk of being born small for gestational age (SGA). These categories of newborns are at increased risk for neurodevelopment impairment. The general movements assessment, in particular at fidgety age, has been used to predict neurological dysfunctions. This study aimed to evaluate growth recovery, presence of fidgety movements at 3 months, and neurodevelopmental outcome at 2 years of age in term late FGR infants and adequate for gestational age (AGA) controls. METHODS: Prospective clinical evaluation. At 3 months auxological parameters (AP) and neurological examination were evaluated while at 24 months neurodevelopment outcome by Griffiths Mental Development Scales (GMDS-R) was evaluated. RESULTS: 38 late FGR and 20 AGA controls completed the study. Despite a significant catch up, at 3 months 13% of late FGR presented at least one auxological parameter <3° percentile. Moreover, 23.7% of late FGR infants did not show fidgety movements compared to 100% AGA controls (p < .001). Cranial circumference at birth resulted a positive predictive factor for FMs (p = .039). At 2 years of age, a difference statistically significant between late FGR and AGA was detected in GMDS-R. CONCLUSION: Independently from growth recovery, fidgety movements resulted less expressed in late FGR infants, and at 2 years of age the neurodevelopmental assessment revealed differences in each domain of evaluation between late FGR and AGA infants, although within normal ranges.
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Retardo do Crescimento Fetal , Recém-Nascido Pequeno para a Idade Gestacional , Lactente , Feminino , Criança , Recém-Nascido , Humanos , Retardo do Crescimento Fetal/diagnóstico , Estudos Prospectivos , Idade GestacionalRESUMO
To investigate the evolution of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in the immune population, we coincupi bated the authentic virus with a highly neutralizing plasma from a COVID-19 convalescent patient. The plasma fully neutralized the virus for seven passages, but, after 45 d, the deletion of F140 in the spike N-terminal domain (NTD) N3 loop led to partial breakthrough. At day 73, an E484K substitution in the receptor-binding domain (RBD) occurred, followed, at day 80, by an insertion in the NTD N5 loop containing a new glycan sequon, which generated a variant completely resistant to plasma neutralization. Computational modeling predicts that the deletion and insertion in loops N3 and N5 prevent binding of neutralizing antibodies. The recent emergence in the United Kingdom, South Africa, Brazil, and Japan of natural variants with similar changes suggests that SARS-CoV-2 has the potential to escape an effective immune response and that vaccines and antibodies able to control emerging variants should be developed.
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Substituição de Aminoácidos , Enzima de Conversão de Angiotensina 2/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/imunologia , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Enzima de Conversão de Angiotensina 2/química , Enzima de Conversão de Angiotensina 2/genética , Animais , Anticorpos Neutralizantes/química , Anticorpos Neutralizantes/genética , Anticorpos Neutralizantes/farmacologia , Anticorpos Antivirais/química , Anticorpos Antivirais/genética , Anticorpos Antivirais/farmacologia , Sítios de Ligação , COVID-19/genética , COVID-19/virologia , Chlorocebus aethiops , Convalescença , Expressão Gênica , Humanos , Evasão da Resposta Imune , Soros Imunes/química , Modelos Moleculares , Mutação , Testes de Neutralização , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/imunologia , SARS-CoV-2/patogenicidade , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Células VeroRESUMO
Preterm infants are at risk for developing altered trajectories of cognitive, social, and linguistic competences compared to a term population. This is mainly due to medical and environmental factors, as they are exposed to an atypical auditory environment and simultaneously, long periods of early separation from their parents. The short-term effects of early vocal contact (EVC) on an infant's early stability have been investigated. However, there is limited evidence of its impact on the infant's autonomic nervous system maturation, as indexed by heart rate variability, and its long-term impact on infant neurodevelopment. Our multi-centric study aims to investigate the effects of EVC on a preterm infant's physiology, neurobehaviour, and development. Eighty stable preterm infants, born at 25-32 weeks and 6 days gestational age, without specific abnormalities, will be enrolled and randomised to either an intervention or control group. The intervention group will receive EVC, where mothers will talk and sing to their infants for 10 min three times per week for 2 weeks. Mothers in the control group will be encouraged to spend the same amount of time next to the incubator and observe the infant's behaviour through a standard cluster of indicators. Infants will be assessed at baseline; the end of the intervention; term equivalent age; and 3, 6, 12, and 24 months corrected age, with a battery of physiological, neurobehavioral, and developmental measures. Early interventions in the neonatal intensive care unit have demonstrated effects on the neurodevelopment of preterm infants, thereby lowering the negative long-term effects of an atypical auditory and interactional environment. Our proposed study will provide new insight into mother-infant early contact as a protective intervention against the sequelae of prematurity during this sensitive period of development. Early intervention, such as EVC, is intuitive and easy to implement in the daily care of preterm infants. However, its long-term effects on infant neurodevelopment and maternal sensitivity and stress are still unclear. Trial Registration: NCT04759573, retrospectively registered, 17 February 2021.
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Recém-Nascido Prematuro , Unidades de Terapia Intensiva Neonatal , Desenvolvimento Infantil , Pré-Escolar , Feminino , Idade Gestacional , Humanos , Lactente , Recém-Nascido de Baixo Peso , Recém-Nascido , Mães , Estudos Multicêntricos como Assunto , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
Background: Few studies conducted to date have observed general movements in infants affected by hypoxic-ischemic encephalopathy (HIE) who underwent therapeutic hypothermia. We investigated whether foot-to-foot contact (FF) could support the predictive value of fidgety movements (FMs) in infants affected by HIE and treated with brain cooling. Methods: Spontaneous motility was video recorded for 3-5 min at 12 weeks post-term age in 58 full-term newborn infants affected by perinatal asphyxia who were cooled due to moderate to severe HIE. FF and FMs were blindly scored by three independent observers. At 24 months, each patient underwent a neurological examination by Amiel-Tison and Grenier. Results: At 24 months, 47 infants had developed typically at neurological examination, eight had developed mild motor impairment, and three developed cerebral palsy (CP). At 12 weeks, 34 (58.6%) infants had shown normal FMs, four of whom developed mild motor impairment. Twenty-four infants (41.4%) exhibited abnormal or no FMs, four of whom developed mild motor impairment and three developed CP. FF was present in 20 infants (34.5%), two of whom developed mild motor impairment. FF was absent in 38 infants (65.5%), six of whom developed mild motor impairment and three developed CP. Both FMs and FF, considered separately, were 100% sensitive for predicting CP at 24 months, but only 61 and 36%, respectively, were specific. Summing the two patterns together, the specificity increases to 73%, considering only CP as an abnormal outcome, and increases to 74% when considering CP plus mild motor impairment. Unexpectedly, fidgety movements were absent in 24 infants with typical motor outcomes, 17 of whom showed a typical motor outcome. Conclusions: FF is already part of motor repertoire at 12 weeks and allows a comparison of spontaneous non-voluntary movements (FMs) to pre-voluntary movements (FF). FF supports FMs for both sensitivity and specificity. A second video recording at 16-18 weeks, when pedipulation is present in healthy infants, is suggested: it may better define the presence or absence of goal-directed motility.
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BACKGROUND: Neonatal hypoxic-ischemic encephalopathy is still a significant cause of neonatal death and neurodevelopmental disabilities, such as cerebral palsy, mental delay, and epilepsy. After the introduction of therapeutic hypothermia, the prognosis of hypoxic-ischemic encephalopathy has improved, with reduction of death and disabilities. However, few studies evaluated whether hypothermia affects rate and severity of postneonatal epilepsy. We evaluated rates, characteristics and prognostic markers of postneonatal epilepsy in infants with moderate to severe hypoxic-ischemic encephalopathy treated or not with therapeutic hypothermia. METHODS: We analyzed clinical data, EEG recordings, cerebral Magnetic Resonance Imaging (MRI) and outcome in 23 cooled and 26 non-cooled asphyxiated neonates (≥36 weeks' gestation), admitted from 2004 to 2012. RESULTS: Among 49 neonates 11 (22%) had postneonatal epilepsy, of which 9 (18%) were non-cooled and 2 (4%) were cooled (P=0.05). Six of 11 infants (55%) had West syndrome, 4 (36%) had focal epilepsy and 1 (9%) had Lennox-Gastaut Syndrome. At multiple logistic regression analysis MRI pattern significantly correlated with postneonatal epilepsy (OR 0.19, 95% CI 0.04-0.88, P=0.03). Extensive lesions in basal ganglia and thalami plus cortical and white matter were associated with postneonatal epilepsy. CONCLUSIONS: Only perinatal asphyxia with extensive lesions in basal ganglia and thalami plus cortical and white matter lesion conveys a high risk for early and severe postneonatal epilepsy. Moreover, therapeutic hypothermia is associated with a decrease of the risk of developing postneonatal epilepsy.
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Encéfalo , Epilepsia Neonatal Benigna/prevenção & controle , Hipotermia Induzida , Hipóxia-Isquemia Encefálica/complicações , Gânglios da Base/diagnóstico por imagem , Eletroencefalografia , Epilepsia Neonatal Benigna/diagnóstico por imagem , Epilepsia Neonatal Benigna/etiologia , Feminino , Humanos , Hipóxia-Isquemia Encefálica/terapia , Recém-Nascido , Síndrome de Lennox-Gastaut , Modelos Logísticos , Imageamento por Ressonância Magnética , Masculino , Prognóstico , Estudos Retrospectivos , Espasmos InfantisRESUMO
A newly identified coronavirus, named SARS-CoV-2, emerged in December 2019 in Hubei Province, China, and quickly spread throughout the world; so far, it has caused more than 49.7 million cases of disease and 1,2 million deaths. The diagnosis of SARS-CoV-2 infection is currently based on the detection of viral RNA in nasopharyngeal swabs by means of molecular-based assays, such as real-time RT-PCR. Furthermore, serological assays detecting different classes of antibodies constitute an excellent surveillance strategy for gathering information on the humoral immune response to infection and the spread of the virus through the population. In addition, it can contribute to evaluate the immunogenicity of novel future vaccines and medicines for the treatment and prevention of COVID-19 disease. The aim of this study was to determine SARS-CoV-2-specific antibodies in human serum samples by means of different commercial and in-house ELISA kits, in order to evaluate and compare their results first with one another and then with those yielded by functional assays using wild-type virus. It is important to identify the level of SARS-CoV-2-specific IgM, IgG and IgA antibodies in order to predict human population immunity, possible cross-reactivity with other coronaviruses and to identify potentially infectious subjects. In addition, in a small sub-group of samples, a subtyping IgG ELISA has been performed. Our findings showed a notable statistical correlation between the neutralization titers and the IgG, IgM and IgA ELISA responses against the receptor-binding domain of the spike protein. Thus confirming that antibodies against this portion of the virus spike protein are highly neutralizing and that the ELISA Receptor-Binding Domain-based assay can be used as a valid surrogate for the neutralization assay in laboratories that do not have biosecurity level-3 facilities.
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Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , COVID-19/sangue , COVID-19/imunologia , Imunoglobulina A/imunologia , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , SARS-CoV-2/imunologia , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/imunologia , Células Cultivadas , Chlorocebus aethiops , Ensaio de Imunoadsorção Enzimática , Humanos , Imunidade Humoral , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Células VeroRESUMO
BACKGROUND: Peroxisome biogenesis disorders (PBDs) are a group of metabolic diseases caused by dysfunction of peroxisomes. Different forms of PBDs are described; the most severe one is the Zellweger syndrome (ZS). We report on an unusual presentation of Zellweger syndrome manifesting in a newborn with severe and fulminant sepsis, causing death during the neonatal period. CASE PRESENTATION: A term male Caucasian neonate presented at birth with hypotonia and poor feeding associated with dysmorphic craniofacial features and skeletal abnormalities. Blood tests showed progressive leukopenia; ultrasounds revealed cerebral and renal abnormalities. He died on the fourth day of life because of an irreversible Gram-negative sepsis. Post-mortem tests on blood and urine samples showed biochemical alterations suggestive of ZS confirmed by genetic test. CONCLUSIONS: ZS is an early and severe forms of PBDs. Peroxisomes are known to be involved in lipid metabolism, but recent studies suggest their fundamental role in modulating immune response and inflammation. In case of clinical suspicion of ZS it is important to focus the attention on the prevention and management of infections that can rapidly progress to death.
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ATPases Associadas a Diversas Atividades Celulares/genética , Infecções por Bactérias Gram-Negativas/genética , Mutação , Peroxissomos/imunologia , Sepse/genética , Síndrome de Zellweger/genética , ATPases Associadas a Diversas Atividades Celulares/deficiência , ATPases Associadas a Diversas Atividades Celulares/imunologia , Evolução Fatal , Expressão Gênica , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/microbiologia , Infecções por Bactérias Gram-Negativas/patologia , Humanos , Imunidade Inata , Recém-Nascido , Masculino , Peroxissomos/microbiologia , Peroxissomos/patologia , Sepse/imunologia , Sepse/microbiologia , Sepse/patologia , Síndrome de Zellweger/imunologia , Síndrome de Zellweger/microbiologia , Síndrome de Zellweger/patologiaRESUMO
The recent outbreak of a novel Coronavirus (SARS-CoV-2) and its rapid spread across the continents has generated an urgent need for assays to detect the neutralising activity of human sera or human monoclonal antibodies against SARS-CoV-2 spike protein and to evaluate the serological immunity in humans. Since the accessibility of live virus microneutralisation (MN) assays with SARS-CoV-2 is limited and requires enhanced bio-containment, the approach based on "pseudotyping" can be considered a useful complement to other serological assays. After fully characterising lentiviral pseudotypes bearing the SARS-CoV-2 spike protein, we employed them in pseudotype-based neutralisation assays in order to profile the neutralising activity of human serum samples from an Italian sero-epidemiological study. The results obtained with pseudotype-based neutralisation assays mirrored those obtained when the same panel of sera was tested against the wild type virus, showing an evident convergence of the pseudotype-based neutralisation and MN results. The overall results lead to the conclusion that the pseudotype-based neutralisation assay is a valid alternative to using the wild-type strain, and although this system needs to be optimised and standardised, it can not only complement the classical serological methods, but also allows serological assessments to be made when other methods cannot be employed, especially in a human pandemic context.
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Betacoronavirus/genética , Infecções por Coronavirus/virologia , Lentivirus/genética , Testes de Neutralização/métodos , Pandemias , Pneumonia Viral/virologia , Animais , Anticorpos Neutralizantes , Anticorpos Antivirais/imunologia , Betacoronavirus/imunologia , COVID-19 , Linhagem Celular , Infecções por Coronavirus/epidemiologia , Humanos , Soros Imunes/imunologia , Itália/epidemiologia , Plasmídeos/genética , Pneumonia Viral/epidemiologia , SARS-CoV-2 , Estudos Soroepidemiológicos , Glicoproteína da Espícula de Coronavírus/biossíntese , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/fisiologia , Transfecção , Vesiculovirus/genética , Carga ViralRESUMO
The micro-neutralization assay is a fundamental test in virology, immunology, vaccine assessment, and epidemiology studies. Since the SARS-CoV-2 outbreak at the end of December 2019 in China, it has become extremely important to have well-established and validated diagnostic and serological assays for this new emerging virus. Here, we present a micro-neutralization assay with the use of SARS-CoV-2 wild type virus with two different methods of read-out. We evaluated the performance of this assay using human serum samples taken from an Italian seroepidemiological study being performed at the University of Siena, along with the human monoclonal antibody CR3022 and some iper-immune animal serum samples against Influenza and Adenovirus strains. The same panel of human samples have been previously tested in enzyme-linked immunosorbent assay (ELISA) as a pre-screening. Positive, borderline, and negative ELISA samples were evaluated in neutralization assay using two different methods of read-out: subjective (by means of an inverted optical microscope) and objective (by means of a spectrophotometer). Our findings suggest that at least 50% of positive ELISA samples are positive in neutralization as well, and that method is able to quantify different antibody concentrations in a specific manner. Taken together, our results confirm that the colorimetric cytopathic effect-based microneutralization assay could be used as a valid clinical test method for epidemiological and vaccine studies.
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Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , COVID-19/diagnóstico , Colorimetria/normas , Microscopia/normas , Testes de Neutralização/normas , SARS-CoV-2/imunologia , Animais , Anticorpos Monoclonais/análise , COVID-19/imunologia , COVID-19/virologia , Linhagem Celular Tumoral , Chlorocebus aethiops , Colorimetria/métodos , Ensaio de Imunoadsorção Enzimática , Hepatócitos/imunologia , Hepatócitos/virologia , Humanos , Soros Imunes/química , Microscopia/métodos , Espectrofotometria , Células Vero , Carga Viral/imunologiaRESUMO
Growing interest in universal influenza vaccines and novel administration routes has led to the development of alternative serological assays that are able to detect antibodies against conserved epitopes. We present a competitive ELISA method that is able to accurately determine the ratio of serum immunoglobulin G directed against the different domains of the hemagglutinin, the head and the stalk. Human serum samples were treated with two variants of the hemagglutinin protein from the A/California/7/2009 influenza virus. The signals detected were assigned to different groups of antibodies and presented as a ratio between head and stalk domains. A subset of selected sera was also tested by hemagglutination inhibition, single radial hemolysis, microneutralization, and enzyme-linked lectin assays. Pre-vaccination samples from adults showed a quite high presence of anti-stalk antibodies, and the results were substantially in line with those of the classical serological assays. By contrast, pre-vaccination samples from children did not present anti-stalk antibodies, and the majority of the anti-hemagglutinin antibodies that were detected after vaccination were directed against the head domain. The presented approach, when supported by further assays, can be used to assess the presence of specific anti-stalk antibodies and the potential boost of broadly protective antibodies, especially in the case of novel universal influenza vaccine approaches.
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To investigate the evolution of SARS-CoV-2 in the immune population, we co-incubated authentic virus with a highly neutralizing plasma from a COVID-19 convalescent patient. The plasma fully neutralized the virus for 7 passages, but after 45 days, the deletion of F140 in the spike N-terminal domain (NTD) N3 loop led to partial breakthrough. At day 73, an E484K substitution in the receptor-binding domain (RBD) occurred, followed at day 80 by an insertion in the NTD N5 loop containing a new glycan sequon, which generated a variant completely resistant to plasma neutralization. Computational modeling predicts that the deletion and insertion in loops N3 and N5 prevent binding of neutralizing antibodies. The recent emergence in the United Kingdom and South Africa of natural variants with similar changes suggests that SARS-CoV-2 has the potential to escape an effective immune response and that vaccines and antibodies able to control emerging variants should be developed. ONE SENTENCE SUMMARY: Three mutations allowed SARS-CoV-2 to evade the polyclonal antibody response of a highly neutralizing COVID-19 convalescent plasma.
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General movements (GMs) in combination with neurological examination and magnetic resonance imaging at term age can accurately determine the risk of cerebral palsy. The present study aimed to assess whether 11 motor and postural patterns concomitant with GMs were associated with cerebral palsy. Video recordings performed after birth in 79 preterm infants were reviewed retrospectively. Thirty-seven infants developed cerebral palsy at 2 years corrected age and the remaining 42 showed typical development. GMs were assessed from preterm to fidgety age and GM trajectories were defined. The 11 motor and postural patterns were evaluated at each age and longitudinally, alone and in combination with GM trajectories. A logistic regression model was used to assess the association between GMs, concomitant motor and postural patterns, and cerebral palsy. We confirmed that high-risk GM trajectories were associated with cerebral palsy (odds ratio = 44.40, 95% confidence interval = 11.74-167.85). An association between concomitant motor and postural patterns and cerebral palsy was found for some of the patterns at term age and for all of them at fidgety age. Therefore, at term age, concomitant motor and postural patterns can support GMs for the early diagnosis of cerebral palsy.
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OBJECTIVES: Current predominant routes of group B Streptococcus (GBS) transmission in preterm neonates admitted to neonatal intensive care unit (NICU) are poorly defined. We report 2 overlapping clusters of GBS late-onset disease (LOD) from June to September 2015 in an Italian NICU. METHODS: During the outbreak, possible sources of transmission (equipment, feeding bottles and breast pumps) were swabbed. Specimens from throat and rectum were collected on a weekly basis from all neonates admitted to NICU. Colonized or infected neonates had cohorting. Bacterial isolates were characterized by serologic and molecular typing methods. RESULTS: GBS was isolated in 2 full-term and 7 preterm neonates. Strains belonged to serotype III, with 3 different sequence types (ST17, ST182 and ST19). Full-term neonates were colonized with GBS strains unrelated to the clusters (ST182 and ST19). Two distinct ST17 strains caused 2 clusters in preterm neonates: a first cluster with 1 case of LOD and a second, larger cluster with 6 LOD in 5 neonates (one of them had recurrence). ST17 strains were isolated from vaginorectal and milk samples of 2 mothers. Two preterm neonates had no evidence of colonization for weeks, until they presented with LOD. CONCLUSIONS: Molecular analyses identified the presence of multiclonal GBS strains and 2 clusters of 7 cases of GBS-LOD. The dynamics of transmission of GBS within the NICU were complex. Breast milk was suspected to be one of the possible sources. In a research setting, the screening of GBS carrier mothers who deliver very preterm could contribute to the tracking of GBS transmission.