Polymeric Membranes Doped with Halloysite Nanotubes Imaged using Proton Microbeam Microscopy

Polymeric membranes are useful tools for water filtration processes, with their performance strongly dependent on the presence of hydrophilic dopants. In this study, polyaniline (PANI)-capped aluminosilicate (halloysite) nanotubes (HNTs) are dispersed into polyether sulfone (PES), with concentrations ranging from 0.5 to 1.5 wt%, to modify the properties of the PES membrane. Both undoped and HNT-doped PES membranes are investigated in terms of wettability (static and time-dependent contact angle), permeance, mechanical resistance, and morphology (using scanning electron microscopy (SEM)). The higher water permeance observed for the PES membranes incorporating PANI-capped HNTs is, finally, assessed and discussed vis-à-vis the real distribution of HNTs. Indeed, the imaging and characterization in terms of composition, spatial arrangement, and counting of HNTs embedded within the polymeric matrix are demonstrated using non-destructive Micro Particle Induced X-ray Emission (µ-PIXE) and Scanning Transmission Ion Microscopy (STIM) techniques. This approach not only exhibits the unique ability to detect/highlight the distribution of HNTs incorporated throughout the whole thickness of polymer membranes and provide volumetric morphological information consistent with SEM imaging, but also overcomes the limits of the most common analytical techniques exploiting electron probes. These aspects are comprehensively discussed in terms of practical analysis advantages.

PIGQ-Related Glycophosphatidylinositol Deficiency Associated with Nonprogressive Congenital Ataxia

The glycophosphatidylinositol (GPI) anchor pathway plays an essential role in posttranslational modification of proteins to facilitate proper membrane anchoring and trafficking to lipid rafts, which is critical for many cell functions, including embryogenesis and neurogenesis. GPI biosynthesis is a multi-step process requiring the activity of over 25 distinct genes, most of them belonging to the phosphatidylinositol glycan (PIG) family and associated with rare neurodevelopmental disorders. PIGQ encodes the phosphatidylinositol glycan class Q protein and is part of the GPI-N-acetylglucosaminyltransferase complex that initiates GPI biosynthesis from phosphatidylinositol (PI) and N-acetylglucosamine (GlcNAc) on the cytoplasmic side of the endoplasmic reticulum (ER). Pathogenic variants in the PIGQ gene have been previously reported in 10 patients with congenital hypotonia, early-infantile epileptic encephalopathy, and premature death occurring in more than half cases. We detected a novel homozygous variant in PIGQ (NM_004204.5: c.1631dupA; p.Tyr544fs*79) by WES trio-analysis of a male patient with a neurodevelopmental disorder characterized by nonprogressive congenital ataxia, intellectual disability, generalized epilepsy, and cerebellar atrophy. Flow cytometry confirmed deficiency of several GPI-anchored proteins on leukocytes (CD14, FLAER). Clinical features of this case broaden the phenotypic spectrum of PIGQ-related GPI deficiency, outlining the importance of glycophosphatidylinositol (GPI) anchor pathway in the pathogenesis of cerebellar ataxia.

Validation of low-cost system for gait assessment in children with ataxia

BACKGROUND

Ataxic syndromes include several rare, inherited and acquired conditions. One of the main issues is the absence of specific, and sensitive automatic evaluation tools and digital outcome measures to obtain a continuous monitoring of subjects' motor ability.

OBJECTIVES

This study aims to test the usability of the Kinect system for assessing ataxia severity, exploring the potentiality of clustering algorithms and validating this system with a standard motion capture system.

METHODS

Gait evaluation was performed by standardized gait analysis and by Kinect v2 during the same day in a cohort of young patient (mean age of 13.8±7.2). We analyzed the gait spatio-temporal parameters and we looked at the differences between the two systems through correlation and agreement tests. As well, we tested for possible correlations with the SARA scale as well. Finally, standard classification algorithm and principal components analysis were used to discern disease severity and groups.

RESULTS

We found biases and linear relationships between all the parameters. Significant correlations emerged between the SARA and the Speed, the Stride Length and the Step Length. PCA results, highlighting that a machine learning approach combined with Kinect-based evaluation shows great potential to automatically assess disease severity and diagnosis.

CONCLUSIONS

The spatio-temporal parameters measured by Kinect cannot be used interchangeably with those parameters acquired with standard motion capture system in clinical practice but can still provide fundamental information. Specifically, these results might bring to the development of a novel system to perform easy and quick evaluation of gait in young patients with ataxia, useful for patients stratification in terms of clinical severity and diagnosis.

Investigations of byzantine wall paintings in the abbey of Santa Maria di Cerrate (Italy) in view of their restoration

In this paper, diagnostic analyses on 12th-13th century byzantine wall paintings in the abbey of Santa Maria di Cerrate (Southern Italy) were carried out preparatory to restoration work promoted by FAI (Fondo Ambiente Italiano). Both the pigments and the areas with a bleaching alteration in the frescoes were analysed using the energy dispersive X-ray fluorescence, the Raman spectroscopy and the scanning electron microscopy equipped with energy dispersive X-ray spectrometer. In particular, ED-XRF analyses were performed in situ on wall paintings, while Raman spectroscopy and SEM-EDX were accomplished on frescoes fragments. The results obtained allowed to determine the chemical composition of the pigments, helping to identify the original parts of the frescoes from the retouched ones. The work also provided important information about the historical-artistic context of the abbey. Archaeometric investigations have indeed revealed the pictorial technique used for the wall paintings of the abbey, as well as the presence of some very valuable pigments, such as lapis lazuli blue.

Spatio-temporal parameters of ataxia gait dataset obtained with the Kinect

Ataxic syndromes include several rare, inherited and acquired conditions. One of the main issues is the absence of specific, and sensitive automatic evaluation tools and digital outcome measures to obtain a continuous monitoring of subjects' motor ability.

Gait evaluation was performed by Kinect v2 in a cohort of young participant affected by ataxia syndrome. The dataset is composed of the spatio-temporal parameters calculated by the skeleton acquired by the Kinect sensor, by the diagnosis of each participant, and by the total score of the clinical scale SARA. These parameters have been previously validated and corrected as requested by the Bland-Altman test.

EMG-based Indicators of Muscular Co-Activation during Gait in Children with Duchenne Muscular Dystrophy

Muscular weakness is one of the main signs associated with the onset and progression of Duchenne Muscular Dystrophy. During motor functions, this disease also determines deviations in muscular activity, especially in terms of coordination and activation between muscles acting on the same joints. In this study, surface EMG activity of the lower limb muscles of 10 children with Duchenne Muscular Dystrophy at different times from disease onset were recorded along with kinematics during unconstrained gait. Muscular co-activation of muscle pairs was then evaluated by extracting different co-activation indicators, and linking them with kinematic markers of motor function. The combination of disease progression and pharmacological treatment resulted in a significant decrease in terms of co-activation indexes for two pairs of agonist-antagonist muscles, and for one of these two pairs the decrease in co-activation was correlated with a decrease in the motor function of gait.

Chlortetracycline, Oxytetracycline, and Tetracycline in Edible Animal Tissues, Liquid Chromatographic Method: Collaborative Study

Thirteen laboratories analyzed samples of edible animal tissues for tetracycline residues. The method included extraction of analytes into buffer, elution from a C18 solid-phase extraction (SPE) cartridge, and reversed-phase liquid chromatographic (LC) analysis, including use of a confirmation column. An additional laboratory, using an alternative LC assay based on a different sample cleanup, also analyzed the samples. Results showed the 2 methods are comparable. The LC method for determination of cholortetracycline, oxytetracycline, and tetracycline in edible animal tissues has been adopted by AOAC INTERNATIONAL. Results from 13 laboratories indicate that the method under study provides generally better results at the higher concentrations tested than at concentrations near the detection limit and that there is less problem with interferences in muscle tissue than in kidney. The method can achieve reliable results for analytes and matrixes studied at concentrations from 0.1 to 0.6 ppm and above, depending on the analyte-matrix combination, with generally better performance to be expected with muscle than with kidney. The poorer performance for fortified samples, particularly kidney, was attributed to additional homogenization steps required to prepare these samples. Recovery of analytes from different

A clinical diagnostic algorithm for early onset cerebellar ataxia

Early onset cerebellar Ataxia (EOAc) comprises a large group of rare heterogeneous disorders. Determination of the underlying etiology can be difficult given the broad differential diagnosis and the complexity of the genotype-phenotype relationships. This may change the diagnostic work-up into a time-consuming, costly and not always rewarding task. In this overview, the Childhood Ataxia and Cerebellar Group of the European Pediatric Neurology Society (CACG-EPNS) presents a diagnostic algorithm for EOAc patients. In seven consecutive steps, the algorithm leads the clinician through the diagnostic process, including EOA identification, application of the Inventory of Non-Ataxic Signs (INAS), consideration of the family history, neuro-imaging, laboratory investigations, genetic testing by array CGH and Next Generation Sequencing (NGS). In children with EOAc, this algorithm is intended to contribute to the diagnostic process and to allow uniform data entry in EOAc databases.

Natural history of a cohort of ABCD1 variant female carriers

BACKGROUND AND PURPOSE

The therapeutic scenario of X-linked adrenoleukodystrophy (X-ALD) is rapidly changing. Whereas the disease is well characterized in men, the condition remains to be fully clarified in women carrying ATP binding cassette subfamily D member 1 (ABCD1) variants. Specifically, data on clinical progression are needed, in order to recommend any appropriate management. The objective of this study was to outline the natural history of a cohort of untreated ABCD1 heterozygous female carriers.

METHODS

Longitudinal data from a single-center population of 60 carriers were retrospectively reviewed. Demographics, anthropometrics, serum very long chain fatty acid (VLCFA) levels, clinical parameters and the Adult ALD Clinical Score (AACS) were collected from every recorded visit in a 7-year period and analyzed to define the phenotype modifications, to determine factors associated with clinical features, and to estimate the annual progression rate and the subsequent sample size for interventional trials.

RESULTS

Thirty-two patients were eligible for the study, and 59.4% were symptomatic at baseline. Clinical severity worsens with age which increases risk of symptom onset, the cut-off of 41 years being crucial for phenoconversion. VLCFA levels were not predictive and did not change over time. Symptomatic carriers were followed up for 3.45 ± 2.1 years. The AACS increased at an annual rate of 0.24 points. The estimated sample size for 30% reduction in annual progression at 80% power was 272.

CONCLUSIONS

This study provides data on the natural disease progression of untreated ABCD1 heterozygous female carriers, demonstrating the relevance of aging. The estimated annual increase of the AACS will be useful for future interventional studies.

Respiratory and cardiac function in congenital muscular dystrophies with alpha dystroglycan deficiency

The aim of this retrospective study was to assess respiratory and cardiac function in a large cohort of patients with congenital muscular dystrophies (CMD) with reduced glycosylation of alphadystroglycan (α-DG). Thirteen of the 115 patients included in the study died between the age of 1 month and 20 years. The age at last follow up of the surviving 102 ranged between 1 year and 68 years (median: 9.3 years). Cardiac involvement was found in 7 of the 115 (6%), 5 with dilated cardiomyopathy, 1 cardiac conductions defects and 1 mitral regurgitation. Respiratory function was impaired in 14 (12%). Ten of the 14 required non invasive nocturnal respiratory support, while the other four required invasive ventilation. Cardiac or respiratory involvement was found in patients with mutations in FKRP, POMT1, POMT2. All of the patients in whom mutation in POMGnT1 were identified had normal cardiac and respiratory function.

Congenital muscular dystrophies with cognitive impairment. A population study

BACKGROUND

Cognitive impairment has been reported in a significant proportion of patients with congenital muscular dystrophies (CMD), generally associated with brain changes.

OBJECTIVES

The aim of this study was to establish 1) the overall prevalence of CMD and cognitive impairment in the Italian population; 2) the frequency of individual genetically defined forms; and 3) the presence of distinct phenotypes not associated with mutations in the known genes.

METHODS

We included all patients with CMD and cognitive impairment followed in all the Italian tertiary neuromuscular centers. Clinical, brain MRI, and morphologic data were collected. Genetic screening of the known genes was performed according to clinical and muscle biopsy findings.

RESULTS

Ninety-two of the 160 (58%) patients with CMD followed in our centers had cognitive impairment. alpha-Dystroglycan (alpha-DG) reduction on muscle biopsy was found in 73/92 (79%), with 42/73 carrying mutations in the known genes. Another 6/92 (7%) showed a laminin alpha2 deficiency on muscle biopsy and 5 of the 6 carried mutations in LAMA2. The remaining 13/92 (14%) patients had normal alpha-DG and laminin alpha2 expression on muscle.

CONCLUSIONS

This is the first population study establishing the prevalence of CMD and cognitive impairment and providing a classification on the basis of clinical, MRI, and genetic findings. We also showed that cognitive impairment was not always associated with alpha-DG or laminin alpha2 reduction or with structural brain changes.

Reliability of the North Star Ambulatory Assessment in a multicentric setting

The aim of this study was to investigate the suitability of the North Star Ambulatory Assessment as a possible outcome measure in multicentric clinical trials. More specifically we wished to investigate the level of training needed for achieving a good interobserver reliability in a multicentric setting. The scale was specifically designed for ambulant children with Duchenne Muscular Dystrophy and includes 17 items that are relevant for this cohort. Thirteen Italian centers participated in the study. In the first phase of the study we provided two training videos and an example of the scale performed on a child. After the first session of training, all the 13 examiners were asked to send a video with an assessment performed in their centre and to score all the videos collected. There were no difficulties in performing the items and in obtaining adequate videos with a hand held camera but the results showed a poor interobserver reliability (<.5). After a second training session with review and discussion of the videos previously scored, the same examiners were asked to score three new videos. The results of this session had an excellent interobserver reliability (.995). The level of agreement was maintained even when the same videos were rescored after a month, showing a significant intra-observer reliability (.95). Our results suggest that the NSAA is a test that can be easily performed, completed in 10 min and can be used in a multicentric setting, providing that adequate training is administered.

Congenital muscular dystrophies with defective glycosylation of dystroglycan: a population study

BACKGROUND

Congenital muscular dystrophies (CMD) with reduced glycosylation of alpha-dystroglycan (alpha-DG) are a heterogeneous group of conditions associated with mutations in six genes encoding proven or putative glycosyltransferases.

OBJECTIVES

The aim of the study was to establish the prevalence of mutations in the six genes in the Italian population and the spectrum of clinical and brain MRI findings.

METHODS

As part of a multicentric study involving all the tertiary neuromuscular centers in Italy, FKRP, POMT1, POMT2, POMGnT1, fukutin, and LARGE were screened in 81 patients with CMD and alpha-DG reduction on muscle biopsy (n = 76) or with a phenotype suggestive of alpha-dystroglycanopathy but in whom a muscle biopsy was not available for alpha-DG immunostaining (n = 5).

RESULTS

Homozygous and compound heterozygous mutations were detected in a total of 43/81 patients (53%), and included seven novel variants. Mutations in POMT1 were the most prevalent in our cohort (21%), followed by POMT2 (11%), POMGnT1 (10%), and FKRP (9%). One patient carried two heterozygous mutations in fukutin and one case harbored a new homozygous variant in LARGE. No clear-cut genotype-phenotype correlation could be observed with each gene, resulting in a wide spectrum of clinical phenotypes. The more severe phenotypes, however, appeared to be consistently associated with mutations predicted to result in a severe disruption of the respective genes.

CONCLUSIONS

Our data broaden the clinical spectrum associated with mutations in glycosyltransferases and provide data on their prevalence in the Italian population.

Longitudinal assessment of visual development in non-syndromic craniosynostosis: a 1-year pre- and post-surgical study

OBJECTIVE

to investigate visual function pre- and post surgery in children with single-suture non-syndromic craniosynostosis

DESIGN

Twenty-nine infants (12 with sagittal synostosis, 10 with trigonocephaly and 7 with anterior plagiocephaly) were longitudinally evaluated using a battery of tests assessing various aspects of visual function, including ocular behaviour, acuity, visual fields and fixation shift. All infants were assessed before surgery and 2, 6 and 12 months after surgery.

RESULTS

Before surgery only 16% of infants had completely normal visual function, while on the assessment performed 12 months after surgery, the number with normal results on all the tests increased to 65%. The only abnormalities found 12 months after surgical correction were mainly found on abnormal oculomotor behaviour in infants with plagiocephaly.

CONCLUSION

Abnormalities of visual function were not frequent in infants with non-syndromic craniosynostosis who underwent surgical correction. Approximately half of the patients had some visual abnormalities before surgery, which subsequently improved, showing a delayed visual maturation rather than persistent abnormalities.

Visual function in infants with non-syndromic craniosynostosis

The aim of this study was to assess various aspects of visual function in children with single-suture, non-syndromic craniosynostosis. Thirty-eight infants (28 males, 10 females; age range 3.5-13mo, mean age 7mo, 11 with plagiocephaly, 12 with trigonocephaly, and 15 with scaphocephaly), were assessed with a battery of tests specifically designed to assess various aspects of visual function in infancy. Thirty-two of the 38 infants had at least one abnormality on one of the aspects of visual function assessed. Abnormal eye movements were found in eight infants of the whole cohort and were mainly found in infants with plagiocephaly (6/11), who also had frequent visual field abnormalities (5/11). In contrast, fixation shift, an aspect of visual function related to the integrity of parietal lobes, was more frequently abnormal in patients with scaphocephaly. Our results suggest that the presence and severity of visual impairment is related to the type of craniosynostosis. Follow-up studies after surgical correction are needed to evaluate the possible beneficial effects of reconstructive surgery on visual function.

Assessment of visual function in children with methylmalonic aciduria and homocystinuria

The aim of this study was to assess various aspects of visual function in 6 patients (age range: 9 months to 7 years and 8 months) with methylmalonic aciduria and homocystinuria. All patients had an ophthalmological examination and were tested with a battery of age-appropriate tests assessing various aspects of visual function such as acuity, visual fields and visual attention. None of the patients had significant retinal abnormalities but all 6 had nystagmus which was associated with strabismus in 3 of the 6. They all had some abnormalities on the behavioral tests assessing visual function which appeared to be related to the age of the patients. Visual impairment was more severe in the 3 patients below 3 years of age and milder in the older patients. The presence and the severity of abnormalities, in contrast, did not depend on the age at onset or the age when treatment was started and were only partly related to brain MRI findings. Severe hydrocephalus and basal ganglia involvement were associated with severe visual impairment, but abnormal visual findings were also present in the children with normal MRI and isolated mild periventricular changes. Our results suggest that age, brain lesions and other factors may be responsible for visual abnormalities in methylmalonic aciduria and homocystinuria. Further studies using early and sequential assessment of visual function are needed to establish whether the differences observed between younger and older children may be related to the duration of therapy.

Bacterial lipoprotein based expression vectors as tools for the characterisation of African swine fever virus (ASFV) antigens

African swine fever virus (ASFV) is the causative agent of an important pig disease for which protective mechanisms are still poorly understood. The present work was aimed at the characterisation of ASFV antigens using previously reported vectors that allow their expression as fusion proteins with the bacterial lipoprotein OprI. Several recombinant clones induced SLA-restricted, ASFV-specific lymphoproliferation and one (A2) was demonstrated to stimulate ASFV-specific CTL activity in vitro, in opposition to the effect of UV inactivated virus. The nucleotide sequence of the fragment cloned in A2 showed 99% identity with a portion of the G1340L ORF of the BA71V isolate, and the expressed fusion lipoprotein induced specific antibodies in vivo. Blood mononuclear leukocytes from a pig immunised with outer membrane preparations from A2 showed to reduce strongly (99.6%) the ASFV yield in cultures of autologous macrophages. However, after inoculation with virulent virus the pig developed acute fatal ASF. Overall our results show that OprI based expression vectors are valuable tools to screen viral antigens in terms of their capacity to trigger immune competent cells.