A novel case of MSTO1 gene related congenital muscular dystrophy with progressive neurological involvement

Recessive mutations in the MSTO1 gene, encoding for a mitochondrial distribution and morphology regulator, have been recently described in a very limited number of patients with multisystem involvement, mostly characterized by myopathy or dystrophy, cerebellar ataxia, pigmentary retinopathy and raised creatine kinase levels. Here we report an additional patient with recessive MSTO1-related muscular dystrophy (MSTO1-RD), and clinical and radiological evidence of progressive cerebellar involvement. Whole-exome sequencing identified two novel MSTO1 missense variants, c.766C > T (p. (Arg256Trp) and c.1435C > T (p. (Pro479Ser), predicted as damaging by in silico tools. We also report a distinct pattern of selective involvement on muscle MRI in MSTO1-RD. This case confirms a consistent MSTO1-related neuromuscular phenotype and in addition suggests a progressive neurological component at least in some patients, in keeping with the mitochondrial role of the defective protein

Digenic inheritance involving a muscle-specific protein kinase and the giant titin protein causes a skeletal muscle myopathy

\ua9 The Author(s) 2024.In digenic inheritance, pathogenic variants in two genes must be inherited together to cause disease. Only very few examples of digenic inheritance have been described in the neuromuscular disease field. Here we show that predicted deleterious variants in SRPK3, encoding the X-linked serine/argenine protein kinase 3, lead to a progressive early onset skeletal muscle myopathy only when in combination with heterozygous variants in the TTN gene. The co-occurrence of predicted deleterious SRPK3/TTN variants was not seen among 76,702 healthy male individuals, and statistical modeling strongly supported digenic inheritance as the best-fitting model. Furthermore, double-mutant zebrafish (srpk3−/−; ttn.1+/−) replicated the myopathic phenotype and showed myofibrillar disorganization. Transcriptome data suggest that the interaction of srpk3 and ttn.1 in zebrafish occurs at a post-transcriptional level. We propose that digenic inheritance of deleterious changes impacting both the protein kinase SRPK3 and the giant muscle protein titin causes a skeletal myopathy and might serve as a model for other genetic diseases

Dynamics of Co-Transcriptional Pre-mRNA Folding Influences the Induction of Dystrophin Exon Skipping by Antisense Oligonucleotides

Antisense oligonucleotides (AONs) mediated exon skipping offers potential therapy for Duchenne muscular dystrophy. However, the identification of effective AON target sites remains unsatisfactory for lack of a precise method to predict their binding accessibility. This study demonstrates the importance of co-transcriptional pre-mRNA folding in determining the accessibility of AON target sites for AON induction of selective exon skipping in DMD. Because transcription and splicing occur in tandem, AONs must bind to their target sites before splicing factors. Furthermore, co-transcriptional pre-mRNA folding forms transient secondary structures, which redistributes accessible binding sites. In our analysis, to approximate transcription elongation, a “window of analysis” that included the entire targeted exon was shifted one nucleotide at a time along the pre-mRNA. Possible co-transcriptional secondary structures were predicted using the sequence in each step of transcriptional analysis. A nucleotide was considered “engaged” if it formed a complementary base pairing in all predicted secondary structures of a particular step. Correlation of frequency and localisation of engaged nucleotides in AON target sites accounted for the performance (efficacy and efficiency) of 94% of 176 previously reported AONs. Four novel insights are inferred: (1) the lowest frequencies of engaged nucleotides are associated with the most efficient AONs; (2) engaged nucleotides at 3′ or 5′ ends of the target site attenuate AON performance more than at other sites; (3) the performance of longer AONs is less attenuated by engaged nucleotides at 3′ or 5′ ends of the target site compared to shorter AONs; (4) engaged nucleotides at 3′ end of a short target site attenuates AON efficiency more than at 5′ end

Digenic inheritance involving a muscle-specific protein kinase and the giant titin protein causes a skeletal muscle myopathy.

In digenic inheritance, pathogenic variants in two genes must be inherited together to cause disease. Only very few examples of digenic inheritance have been described in the neuromuscular disease field. Here we show that predicted deleterious variants in SRPK3, encoding the X-linked serine/argenine protein kinase 3, lead to a progressive early onset skeletal muscle myopathy only when in combination with heterozygous variants in the TTN gene. The co-occurrence of predicted deleterious SRPK3/TTN variants was not seen among 76,702 healthy male individuals, and statistical modeling strongly supported digenic inheritance as the best-fitting model. Furthermore, double-mutant zebrafish (srpk3-/-; ttn.1+/-) replicated the myopathic phenotype and showed myofibrillar disorganization. Transcriptome data suggest that the interaction of srpk3 and ttn.1 in zebrafish occurs at a post-transcriptional level. We propose that digenic inheritance of deleterious changes impacting both the protein kinase SRPK3 and the giant muscle protein titin causes a skeletal myopathy and might serve as a model for other genetic diseases

Contribution of Human Muscle-Derived Cells to Skeletal Muscle Regeneration in Dystrophic Host Mice

Background: Stem cell transplantation is a promising potential therapy for muscular dystrophies, but for this purpose, the cells need to be systemically-deliverable, give rise to many muscle fibres and functionally reconstitute the satellite cell niche in the majority of the patient's skeletal muscles. Human skeletal muscle-derived pericytes have been shown to form muscle fibres after intra-arterial transplantation in dystrophin-deficient host mice. Our aim was to replicate and extend these promising findings.Methodology/Principal Findings: Isolation and maintenance of human muscle derived cells (mdcs) was performed as published for human pericytes. Mdscs were characterized by immunostaining, flow cytometry and RT-PCR; also, their ability to differentiate into myotubes in vitro and into muscle fibres in vivo was assayed. Despite minor differences between human mdcs and pericytes, mdscs contributed to muscle regeneration after intra-muscular injection in mdx nu/nu mice, the CD56+ sub-population being especially myogenic. However, in contrast to human pericytes delivered intra-arterially in mdx SCID hosts, mdscs did not contribute to muscle regeneration after systemic delivery in mdx nu/nu hosts.Conclusions/Significance: Our data complement and extend previous findings on human skeletal muscle-derived stem cells, and clearly indicate that further work is necessary to prepare pure cell populations from skeletal muscle that maintain their phenotype in culture and make a robust contribution to skeletal muscle regeneration after systemic delivery in dystrophic mouse models. Small differences in protocols, animal models or outcome measurements may be the reason for differences between our findings and previous data, but nonetheless underline the need for more detailed studies on muscle-derived stem cells and independent replication of results before use of such cells in clinical trials

Provenienza di ossidiana di Selva dei Muli (Frosinone)

Sono stati sottoposti a determinazione di provenienza, in modo non distruttivo, gli unici tre reperti in ossidiana rinvenuti a Selva dei Muli (FR). Le analisi degli elementi maggiori mediante SEM-EDS e la determinazione delle intensità dei raggi X di alcuni elementi in traccia mediante FRX ha permesso di stabilire la fonte di approvvigionamento di due campioni di ossidiana da Lipari e di un terzo da Palmarola

The Gargano Promontory Flint: Mining Practices and Archaeometric Characterisation

An archaeometric project on prehistoric mining has been carried out in the Gargano promontory, in south-eastern Italy, since 1986, leading to the discovery of a large network of at least twenty mining sites, which was active from the Early Neolithic to the Early Bronze Age. The large area in which the mines are located, the considerable size of some mines and the skills required, together with the long duration of mining activities (four millennia), enable us to regard the Gargano as one of the main areas of flint supply in the central-northern Mediterranean. Three geological Gargano formations were mined: the Maiolica, Scaglia and Peschici formations. They appear to differ significantly with regard to the morphology of the flint. In the mines opened in the Nummulite limestone formation, flint seems to occur only as generally rather large lenticular nodules (often more than one metre in diameter). The Maiolica and Scaglia formations are different: the exploited flints primarily occur in the form of spherical and irregular nodules, only in some cases associated with lenticular lists. During the sixth millennium BC on the Gargano promontory we exclusively find flint mines with entrances opened into the slope of a hill and developing sub-horizontally. This type of mining generated large amounts of mining debris that were accumulated outside the mine and that are sometimes still preserved in their entirety. Neolithic mining techniques in the Gargano underwent a radical transformation from the fifth millennium BC on and especially during the fourth millennium BC: rather small mines can be identified that are characterised by vertical access to the flint-bearing formations, with or without horizontal digging at the base of the shafts. Systematic characterisation studies of the flint from primary and secondary Gargano sources are still lacking and the paper presents the plan and the preliminary results of a new project, applying multi-parametric characterisation obtained by non-destructive approaches that are rapid and economic (during this initial stage of the project macroscopic/petrographic description, colour and reflectance/gloss measurements). A total of 151 flint samples, representative of the three flint-bearing limestone formations, the ancient exploitation of which is demonstrated by mining indicators, and of a fourth formation (Fucoid Marls), which has not provided evidence of flint mining yet, was collected. The flint samples were taken from Neolithic mines and from accessible flint outcrops throughout the Gargano promontory. The macroscopic description of the flint samples provided a matrix of categorical and numerical data which helps to identify the distinctive features of the four formations investigated. Spectro-colorimetry provided coordinates in CIE L*a*b* colour space and reflectance in the visible spectrum of the flint matrix. The two main mining districts hitherto identified by archaeologists, namely those of Vieste and Peschici, cut into specific formations (Peschici limestone and Maiolica respectively), with mines that exploited flint with various characteristics even within the same formation. However, we observed some chromatic homogeneity at site level. This classification of chromatic and reflectance data confirms the similarities visible to the naked eye between most of the samples from the Maiolica and the Peschici limestone formations, which also turned out to be more homogeneous than the Scaglia and the Fucoid Marls formations. No mines were found in the Fucoid Marls formation, though the quality of flint was similar to that of most of the mining sites in the other formations. Although our interpretations have to be tested with chemical and mineralogical data, the statistical approach using quantitative macroscopic data seems to be a promising way of classifying and correlating geological and archaeological flints from the Gargano. Following the steps of the multi-analytical protocol, flints will be analysed with Raman spectroscopy to determine their mineralogical composition, whereas the chemical composition will be obtained by LA-ICP-MS. A detailed micro-structural and palaeontological study will be carried out using a scanning electron microscopy in order to distinguish flint sources of different ages

Variability and continuity of ceramic manufacturing of prehistoric pottery from Upper Nubia, Sudan: An ethnographic comparison

In Nubia (currently northern Sudan), the art of making pottery has a very ancient and durable tradition, dating 20 back to the earlyHolocene and preceding the introduction of a food-producing economy. Ethnographic case stud- 21 ies have demonstrated that this tradition has been preserved in many areas of the country. This paper presents a 22 comparative study of ancient and modern traditional ceramics fromfour prehistoric sites at Sai Island, in the river 23 Nile, and a present-dayworkshop located in the nearby village of Abri. The aim of the study was to investigate any 24 diachronic changes in the selection of clayey raw material and the technological processes of themanufacturing 25 sequence. The study combined macroscopic and analytical approaches and examined a large set of ceramic and 26 local clay samples by means of petrographic (OM), mineralogical (X-ray powder diffraction; XRPD) and chemical 27 (X-ray fluorescence; XRF) analyses. The resulting data underline a remarkable continuity in raw material sourc- 28 ing and composition, as well as in many technological processes, from the ceramic assemblages dating from 29 Abkan cultural horizon (c. 5500 BCE) until to the present-day production in Abri. This continuity emerged after 30 a preceding discontinuity, indicated by a different selection of clay raw material and tempers in the oldest pro- 31 duction dating to the Khartoum Variant horizon (c. 7600–4800 BCE)

TEXTURAL AND MORPHOMETRIC ANALYSIS APPLIED TO HOLOCENE POTTERY FROM TAKARKORI ROCK SHELTER (SW LIBYA, CENTRAL SAHARA): A QUANTITATIVE SEDIMENTOLOGICAL APPROACH

This paper proposes the application of digital image processing of plane- and cross-polarized light photomicrographs to textural and morphometric analysis as an extension of routine petrographic characterization. The aim is to answer questions on the provenance and technology of quartz- and calcite-bearing potsherds from the Takarkori rock shelter (Libyan Sahara, from around 8900 to 4200 uncal. years BP). Specific processing algorithms run on image analysis freeware (ImageJ) isolate quartz and calcite inclusions to obtain quantitative textural and morphometric data that are useful in identifying different local fluvial and swampy sedimentary environments as sources of sandy clays for pottery