Light environment and Seasonal Dynamics of Microalgae in the Annual Sea Ice at Terra Nova Bay, Ross Sea, Antarctica

We investigated the physical conditions of the Spring pack ice environment at Terra Nova Bay to understand their influence on the structure and physiology of sympagic microalgae. Bio-optical methods were used to study the availability and spectral quality of solar radiation, both inside and underneath the ice cover. Pack ice thickness was around 2.5 m, with a temperature between -2 and -7°C. On average, only 1.4% of surface PAR penetrated to the bottom ice and less than 0.6% below platelet ice level. Surface UV-B radiation under the bottom ice was 0.2-0.4%. Biomass concentrations up to 2400 mg Chl a m-3, dominated by two species of diatoms (Entomoneis kjellmannii and Nitschia cf. stellata), showed marked spatial and temporal patterns. Maximum values were in the platelet ice during the first half of November, and in the bottom ice two weeks later. Strong shade adaptation characteristics emerged clearly and explained the relevant abundance of microalgae within the sea ice, with specific absorption coefficients (a*) as low as 0.005 m2 (mg Chl a)-1 and the photo-acclimation index (Ek) in the range of in situ irradiance. The biomass specific production values were low, around 0.12-0.13 mg C mg Chl a-1 h-1. The hypothesis suggesting bottom ice colonization by platelet ice microalgae is supported here

A paradigmatic autistic phenotype associated with loss of PCDH11Y and NLGN4Y genes

Background: Most studies relative to Y chromosome abnormalities are focused on the sexual developmental disorders. Recently, a few studies suggest that some genes located on Y chromosome may be related to different neurodevelopment disorders. Case presentation: We report a child with sexual developmental disorder associated with a peculiar phenotype characterized by severe language impairment and autistic behaviour associated with a mosaicism [45,X(11)/46,XY(89)] and a partial deletion of the short and long arm of Y chromosome (del Yp11.31q11.23) that also involves the loss of both PCDH11Y and NLGN4Y genes. To our knowledge no study has ever reported the occurrence of the lack of both PCDH11Y and NLGN4Y located in the Y chromosome in the same patient. Conclusions: We hypothesized a functional complementary role of PCDH11Y and NLGN4Y within formation/maturation of the cerebral cortex. The impairment of early language development may be mainly related to the lack of PCDH11Y that underlies the early language network development and the later appearance of the autistic behaviour may be mainly related to deficit of inhibitory glicinergic neurotransmission NLGN4Y-linked

Commonalities and distinctions between two neurodevelopmental disorder subtypes associated with SCN2A and SCN8A variants and literature review

This study was aimed to analyze the commonalities and distinctions of voltage-gated sodium channels, Nav1.2, Nav1.6, in neurodevelopmental disorders. An observational study was performed including two patients with neurodevelopmental disorders. The demographic, electroclinical, genetic, and neuropsychological characteristics were analyzed and compared with each other and then with the subjects carrying the same genetic variants reported in the literature. The clinical features of one of them argued for autism spectrum disorder and developmental delay, the other for intellectual disability, diagnoses confirmed by the neuropsychological assessment. The first patient was a carrier of SCN2A (p.R379H) variant while the second was carrier of SCN8A (p.E936K) variant, both involving the pore loop of the two channels. The results of this study suggest that the neurodevelopmental disorders without overt epilepsy of both patients can be the consequences of loss of function of Nav1.2/Nav1.6 channels. Notably, the SCN2A variant, with an earlier expression timing in brain development, resulted in a more severe phenotype as autism spectrum disorder and developmental delay, while the SCN8A variant, with a later expression timing, resulted in a less severe phenotype as intellectual disability

Variable phenotype in 17q12 microdeletions: Clinical and molecular characterization of a new case

Microdeletions of 17q12 including the hepatocyte nuclear factor 1 beta (HNF1B) gene, as well as point mutations of this gene, are associated with the Renal Cysts and Diabetes syndrome (RCAD, OMIM 137920) and genitourinary alterations. Also, microdeletions encompassing HNF1B were identified as a cause of Mayer\u2013Rokitansky\u2013 K\ufcster\u2013Hauser Syndrome (MRKH, OMIM277000) in females and, recently,were associatedwith intellectual disability, autistic features, cerebral anomaly and facial dysmorphisms. In this report, we describe a boywith a deletion in 17q12 region detected by SNP array, encompassing the HNF1B gene, that showed dysmorphic features, intellectual disability (ID), serious speech delay and autistic features. In addition, obesity was observed. In order to study the parental origin of the rearrangement, we analyzed selected SNPs in the deleted area in the patient and his parents, showing Mendelian incompatibilities suggesting a de novo deletion on the chromosome of maternal origin. Our case confirms the incomplete penetrance and variable expressivity of this deletion, its complex clinical variability, and strengthens the evidence that ID and stereotyped behaviors may be part of the phenotypic spectrum characterizing the affected patients. Also, it is useful to further delineate the phenotypes associated to the deletion being the first case in which obesity has been documented. We present a genotype\u2013phenotype correlation discussing the possible role of some genes, encompassed by the deletion, in the etiology of the observed phenotypes

Autism spectrum disorder in Italy: demand for an integrated epidemiological surveillance system.

Autism spectrum disorder (ASD) is a complex neurodevelopmental syndrome of emerging public health concern, according to a documented significant increase of diagnosed cases of ASD in Europe and USA. In Italy, actually, it is not possible to estimate at national level a reliable ASD occurrence by using existing health and scholastic data flows. The lack of information has implications on social and healthcare services dedicated to subjects affected by ADS. The database of the Italian institute in charge of social and security assistance was accessed at the provincial level to investigate the ASD cases occurred in the Palermo province. The official reports of all subjects visited in 2013 by INPS physicians were analyzed by using an automatic software and diagnosis consistent with ASD were ex- tracted and flagged. Our findings support the choice of alternative use of INPS administrative database in order to define a reliable ASD occurrence estimate as first step to develop an integrated epidemiological surveillance system on AS

Devices for less invasive surfactant therapy: a manikin study

peer reviewedBackground: “Less invasive surfactant therapy” (LIST), or tracheal instillation of surfactant through a small catheter in spontaneously breathing infants, is gaining popularity. Different catheters are currently used for this purpose: a nasogastric tube inserted with (LISA) or without (Take Care) Magill’s forceps, a 13 cm 16G adult angiocath (MIST), a 30 cm F4 angiography catheter (Stockholm). We developed a specific device by combining a F5 umbilical catheter and an intubation stylet (Liege). We aimed to compare those 5 devices using INSURE as a reference. Methods: 20 neonatologists from 4 institutions supporting different surfactant instillation policies intubated 2 manikin heads with the 5 catheters and an endotracheal tube in a predetermined random sequence. Water was flushed trough the catheter. Video review provided times between laryngoscope (T1) or catheter insertion (T2) in the mouth and water flowing from the trachea. Participants gave an ease of use score (range: 1-9) for each catheter. Results: Procedural times were longer with the Take Care method and shorter with the Liège device (Table). Failure rates were higher for LIST procedures than for INSURE. Take Care and LISA were rated as more difficult, while Liège, Stockholm and INSURE were considered easier. Conclusions: LIST procedures remain difficult, even on a manikin. The choice of catheter is important. A device combining the rigidity of a stylet with the soft distal end of an umbilical catheter is associated with procedures of shorter duration and is considered easier by neonatologists