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STUDY OBJECTIVE: We present a mathematical model of sleep-EEG structure applied to the analysis of sleep patterns in narcoleptics by combining the 2-process model of sleep regulation and the reciprocal interaction model of REM regulation suggested by McCarley and Hobson. The aim was the individuation of parameters characterizing narcoleptic sleep in comparison to controls. DESIGN: Polysomnographic data were drawn from a previous study about sleep in narcolepsy. The mathematical model was fitted to quantitative EEG data by an optimization procedure. SETTING: Polysomnographic data were recorded in single and sound attenuated hospital rooms, for one night following an adaptation night. PARTICIPANTS: 9 narcoleptic subjects (7 males, 2 females, mean age 39.6 +/- 4.3 years) and 9 age- and sex- matched controls. MEASUREMENTS: Slow Wave Activity (SWA) time series were evaluated by spectral analysis. The sleep model was fitted to SWA profile for each recording and to the averaged SWA profile for each group. Bartlett and Kolmogorov-Smirnov test were used to evaluate the goodness of fit and the accuracy of model predictions. RESULTS: In both controls and narcoleptics the optimization procedure produced a good fit of SWA raw data. The only significant difference between the groups were the RemOn/RemOff coupling parameters, reflecting an enhanced strength of the REM oscillator in narcoleptics. CONCLUSIONS: The mathematical model of sleep provides a substantial description of empirical patterns for both controls and narcoleptics. The variation of values in the parameters describing the strength of RemOn /RemOff interaction is the major feature characterizing narcoleptics; it can explain sleep onset REM periods (SOREMPs) and variations of REM-NREM sleep cycle duration.

There is growing evidence that cyclic alternating pattern (CAP) and arousals are woven into the basic mechanisms of sleep regulation. In the present study, the overnight sleep cycles (SC) of 20 normal subjects were analyzed according to their stage composition, CAP rate, phase A subtypes and arousals. Individual SC were then divided into 10 normalized temporal epochs. CAP parameters and arousals were measured in each epoch and averaged in relation to the SC order. Subtypes A2 and A3 of CAP in non-rapid eye movement (NREM) sleep, and arousals, both in REM and NREM sleep when not coincident with a A2 or A3 phases, were lumped together as fast electroencephalographic (EEG) activities (FA). Subtypes A1 of CAP, characterized by slow EEG activities (SA), were analyzed separately. The time distribution of SA and FA was compared to the mathematical model of normal sleep structure including functions representing the homeostatic process S, the circadian process C, the ultradian process generating NREM/REM cycles and the slow wave activity (SWA) resulting from the interaction between homeostatic and ultradian processes. The relationship between SA and FA and the sleep-model components was evaluated by multiple regression analysis in which SA and FA were considered as dependent variables while the covariates were the process S, process C, SWA, REM-on and REM-off activities and their squared values. Regression was highly significant (P < 0.0001) for both SA and FA. SA were prevalent in the first three SC, and exhibited single or multiple peaks immediately before and in the final part of deep sleep (stages 3 + 4). The peaks of FA were delayed and prevailed during the pre-REM periods of light sleep (stages 1 + 2) and during REM sleep. SA showed an exponential decline across the successive SC, according to the homeostatic process. In contrast, the distribution of FA was not influenced by the order of SC, with periodic peaks of FA occurring before the onset of REM sleep, in accordance with the REM-on switch. The dynamics of CAP and arousals during sleep can be viewed as an intermediate level between cellular activities and macroscale EEG phenomena as they reflect the decay of the homeostatic process and the interaction between REM-off and REM-on mechanisms while are slightly influenced by circadian rhythm.

The Saccharopolyspora erythraea gene (fdxA) corresponding to a previously purified ferredoxin [Shafiee and Hutchinson, J. Bacteriol., 170 (1988) 1548–1553] was cloned using an oligodeoxyribonucleotide probe based on the N-terminal sequence of the ferredoxin. The nucleotide sequence of a 1.3-kb segment encompassing fdxA indicates that the corresponding protein, SeFdI, is 105 amino acids long, and very similar to other 7Fe ferredoxins. A partial open reading frame closely linked to fdxA was also detected. Disruption of fdxA was attempted by replacing the wild-type allele with an in vitro mutated copy. The failure to construct an fdxA mutant strain suggests that fdxA lies in an essential region of the S. erythraea chromosome.

The objective of our study was to evaluate the impact of the COVID-19 pandemic on the emotional and behavioral symptoms in minors with neuropsychiatric disorders and on parental stress through a standardized neuropsychological assessment, comparing the data collected before the pandemic with those collected during the lock-down. Another goal of our study was to analyze the relationship between parental stress and behavioral/emotional symptoms in children. Our study was conducted on 383 families of patients who had already been referred at the Child Neuropsychiatry Unit of the University Hospital of Salerno for different neuropsychiatric conditions. All the parents completed two neuropsychological standardized questionnaires for the assessment of parental stress (PSI—Parenting Stress Index-Short Form) and the emotional/behavioral problems of their children (Child Behaviour CheckList). The data collected during the pandemic were compared with those collected from questionnaires administered during the six months preceding the pandemic, as is our usual clinical practice. The comparison between the mean scores of PSI and CBCL before and after the pandemic showed a statistically significant increase in all subscales analyzed in the total sample. The correlation analysis showed significant positive relationship between the subscale Total Stress of PSI and the subscales Total Problems and Internalizing Problems of CBCL. Our study suggested that the COVID-19 pandemic and the corresponding measures adopted led to an increase in internalizing and externalizing symptoms in children and adolescents with neuropsychiatric disorder. Similarly, parental stress increased during COVID-19 and ahigher level of stress in parents can be related to the internalizing symptoms of their children.

Purpose: The importance of dental care and oral hygiene is often underestimated in people with autism spectrum disorder (ASD). Comorbidity with dental anxiety is greater in ASD subjects who also show unusual reactions to sensory stimuli. The aim of our study was to assess the efficacy for a sensory-adapted environment and targeted methods in reducing anxiety and positively influencing cooperation in children with ASD during a dental examination or specific treatments. Material and methods: The sample consisted of 50 Italian children with a diagnosis of ASD (36 males and 14 females; aged 9–10 years) presenting with mild intellectual disability (ID) and verbal language skills. The subjects enrolled in the study had at least two decayed teeth and all were treated in two different dental environments: regular dental environment (RDE) and sensory-adapted dental environment (SADE). Results: 20% of the sample was successfully treated in RDE, while 68% of subjects were successfully treated in SADE. Conclusions: Results suggest that a sensory-adapted environment positively affects the therapeutic dental treatment in patients with ASD and reaffirm that sensory dysregulation in children with ASD is a crucial factor influencing the successful outcome of oral care.

The glycopeptide A40926, produced by the actinomycete Nonomuraea gerenzanensis, is the precursor of dalbavancin, a second-generation glycopeptide antibiotic approved for clinical use in the USA and Europe in 2014 and 2015, respectively. The final product of the biosynthetic pathway is an O-acetylated form of A40926 (acA40926). Glycopeptide biosynthesis in N. gerenzanensis is dependent upon the dbv gene cluster that encodes, in addition to the two essential positive regulators Dbv3 and Dbv4, the putative members of a two-component signal transduction system, specifically the response regulator Dbv6 and the sensor kinase Dbv22. The aim of this work was to assign a role to these two genes. Our results demonstrate that deletion of dbv22 leads to an increased antibiotic production with a concomitant reduction in glycopeptide resistance. Deletion of dbv6 results in a similar phenotype, although the effects are not as strong as in the Δdbv22 mutant. Consistently, quantitative RT-PCR analysis showed that Dbv6 and Dbv22 negatively regulate the regulatory genes (dbv3 and dbv4), as well as some dbv biosynthetic genes (dbv23 and dbv24), whereas Dbv6 and Dbv22 positively regulate transcription of the single, cluster-associated resistance gene. Finally, we demonstrate that exogenously added acA40926 and its precursor A40926 can modulate transcription of dbv genes but with an opposite extent: A40926 strongly stimulates transcription of the Dbv6/Dbv22 target genes while acA40926 has a neutral or negative effect on transcription of those genes. We propose a model in which glycopeptide biosynthesis in N. gerenzanensis is modulated through a positive feedback by the biosynthetic precursor A40926 and a negative feedback by the final product acA40926. In addition to previously reported control systems, this sophisticated control loop might help the producing strain cope with the toxicity of its own product. This work, besides leading to improved glycopeptide producing strains, enlarges our knowledge on the regulation of glycopeptide biosynthesis in actinomycetes, setting N. gerenzanensis and its two-component system Dbv6-Dbv22 apart from other glycopeptide producers.

A bacterial artificial chromosomal library of Nonomuraea sp. ATCC39727 was constructed using Escherichia coli-Streptomyces artificial chromosome (ESAC) and screened for the presence of dbv genes known to be involved in the biosynthesis of the glycopeptide A40926. dbv genes were cloned as two large, partially overlapping, fragments and transferred into the host Streptomyces lividans, thus generating strains S. lividansColon, two colonsNmESAC50 and S. lividansColon, two colonsNmESAC57. The heterologous expression of Nonomuraea genes in S. lividans was successfully demonstrated by using combined RT-PCR and proteomic approaches. MALDI-TOF analysis revealed that a Nonomuraea ABC transporter is expressed as two isoforms in S. lividans. Moreover, its expression may not require a Nonomuraea positive regulator at all, as it is present at similar levels in both clones even though S. lividansColon, two colonsNmESAC57 lacks regulatory genes. Considered together, these results show that S. lividans expresses Nonomuraea genes from their own promoters and support the idea that S. lividans can be a good host for genetic analysis of Nonomuraea.