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1.
Sci Rep ; 14(1): 8533, 2024 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609424

RESUMO

Craniosynostosis (CS) is a major birth defect resulting from premature fusion of cranial sutures. Nonsyndromic CS occurs more frequently than syndromic CS, with sagittal nonsyndromic craniosynostosis (sNCS) presenting as the most common CS phenotype. Previous genome-wide association and targeted sequencing analyses of sNCS have identified multiple associated loci, with the strongest association on chromosome 20. Herein, we report the first whole-genome sequencing study of sNCS using 63 proband-parent trios. Sequencing data for these trios were analyzed using the transmission disequilibrium test (TDT) and rare variant TDT (rvTDT) to identify high-risk rare gene variants. Sequencing data were also examined for copy number variants (CNVs) and de novo variants. TDT analysis identified a highly significant locus at 20p12.3, localized to the intergenic region between BMP2 and the noncoding RNA gene LINC01428. Three variants (rs6054763, rs6054764, rs932517) were identified as potential causal variants due to their probability of being transcription factor binding sites, deleterious combined annotation dependent depletion scores, and high minor allele enrichment in probands. Morphometric analysis of cranial vault shape in an unaffected cohort validated the effect of these three single nucleotide variants (SNVs) on dolichocephaly. No genome-wide significant rare variants, de novo loci, or CNVs were identified. Future efforts to identify risk variants for sNCS should include sequencing of larger and more diverse population samples and increased omics analyses, such as RNA-seq and ATAC-seq.


Assuntos
Craniossinostoses , Estudo de Associação Genômica Ampla , Humanos , Alelos , Proteína Morfogenética Óssea 2/genética , Craniossinostoses/genética , DNA Intergênico/genética , Sequenciamento Completo do Genoma , RNA Longo não Codificante
2.
Sci Rep ; 14(1): 8546, 2024 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609399

RESUMO

In cases of osseous defects, knowledge of the anatomy, and its age and sex-related variations, is essential for reconstruction of normal morphology. Here, we aimed at creating a 3D atlas of the human mandible in an adult sample using dense landmarking and geometric morphometrics. We segmented 50 male and 50 female mandibular surfaces from CBCT images (age range: 18.9-73.7 years). Nine fixed landmarks and 510 sliding semilandmarks were digitized on the mandibular surface, and then slid by minimizing bending energy against the average shape. Principal component analysis extracted the main patterns of shape variation. Sexes were compared with permutation tests and allometry was assessed by regressing on the log of the centroid size. Almost 49 percent of shape variation was described by the first three principal components. Shape variation was related to width, height and length proportions, variation of the angle between ramus and corpus, height of the coronoid process and inclination of the symphysis. Significant sex differences were detected, both in size and shape. Males were larger than females, had a higher ramus, more pronounced gonial angle, larger inter-gonial width, and more distinct antegonial notch. Accuracy of sexing based on the first two principal components in form space was 91 percent. The degree of edentulism was weakly related to mandibular shape. Age effects were not significant. The resulting atlas provides a dense description of mandibular form that can be used clinically as a guide for planning surgical reconstruction.


Assuntos
Mandíbula , Caracteres Sexuais , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Epífises , Articulações , Mandíbula/anatomia & histologia , Mandíbula/diagnóstico por imagem , Polímeros
3.
Stem Cell Res Ther ; 14(1): 339, 2023 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-38012707

RESUMO

BACKGROUND: The secretome of mesenchymal stromal cells isolated from the amniotic membrane (hAMSCs) has been extensively studied for its in vitro immunomodulatory activity as well as for the treatment of several preclinical models of immune-related disorders. The bioactive molecules within the hAMSCs secretome are capable of modulating the immune response and thus contribute to stimulating regenerative processes. At present, only a few studies have attempted to define the composition of the secretome, and several approaches, including multi-omics, are underway in an attempt to precisely define its composition and possibly identify key factors responsible for the therapeutic effect. METHODS: In this study, we characterized the protein composition of the hAMSCs secretome by a filter-aided sample preparation (FASP) digestion and liquid chromatography-high resolution mass spectrometry (LC-MS) approach. Data were processed for gene ontology classification and functional protein interaction analysis by bioinformatics tools. RESULTS: Proteomic analysis of the hAMSCs secretome resulted in the identification of 1521 total proteins, including 662 unique elements. A number of 157 elements, corresponding to 23.7%, were found as repeatedly characterizing the hAMSCs secretome, and those that resulted as significantly over-represented were involved in immunomodulation, hemostasis, development and remodeling of the extracellular matrix molecular pathways. CONCLUSIONS: Overall, our characterization enriches the landscape of hAMSCs with new information that could enable a better understanding of the mechanisms of action underlying the therapeutic efficacy of the hAMSCs secretome while also providing a basis for its therapeutic translation.


Assuntos
Âmnio , Células-Tronco Mesenquimais , Humanos , Âmnio/metabolismo , Proteômica/métodos , Secretoma , Células-Tronco Mesenquimais/metabolismo , Espectrometria de Massas
4.
Int J Mol Sci ; 24(19)2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37834461

RESUMO

Saliva houses over 2000 proteins and peptides with poorly clarified functions, including proline-rich proteins, statherin, P-B peptides, histatins, cystatins, and amylases. Their genes are poorly conserved across related species, reflecting an evolutionary adaptation. We searched the nucleotide substitutions fixed in these salivary proteins' gene loci in modern humans compared with ancient hominins. We mapped 3472 sequence variants/nucleotide substitutions in coding, noncoding, and 5'-3' untranslated regions. Despite most of the detected variations being within noncoding regions, the frequency of coding variations was far higher than the general rate found throughout the genome. Among the various missense substitutions, specific substitutions detected in PRB1 and PRB2 genes were responsible for the introduction/abrogation of consensus sequences recognized by convertase enzymes that cleave the protein precursors. Overall, these changes that occurred during the recent human evolution might have generated novel functional features and/or different expression ratios among the various components of the salivary proteome. This may have influenced the homeostasis of the oral cavity environment, possibly conditioning the eating habits of modern humans. However, fixed nucleotide changes in modern humans represented only 7.3% of all the substitutions reported in this study, and no signs of evolutionary pressure or adaptative introgression from archaic hominins were found on the tested genes.


Assuntos
Hominidae , Proteínas e Peptídeos Salivares , Humanos , Animais , Proteínas e Peptídeos Salivares/genética , Histatinas , Proteoma , Nucleotídeos
5.
Cell Death Dis ; 13(9): 793, 2022 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-36114172

RESUMO

Muscle-resident non-myogenic mesenchymal cells play key roles that drive successful tissue regeneration within the skeletal muscle stem cell niche. These cells have recently emerged as remarkable therapeutic targets for neuromuscular disorders, although to date they have been poorly investigated in facioscapulohumeral muscular dystrophy (FSHD). In this study, we characterised the non-myogenic mesenchymal stromal cell population in FSHD patients' muscles with signs of disease activity, identified by muscle magnetic resonance imaging (MRI), and compared them with those obtained from apparently normal muscles of FSHD patients and from muscles of healthy, age-matched controls. Our results showed that patient-derived cells displayed a distinctive expression pattern of mesenchymal markers, along with an impaired capacity to differentiate towards mature adipocytes in vitro, compared with control cells. We also demonstrated a significant expansion of non-myogenic mesenchymal cells (identified as CD201- or PDGFRA-expressing cells) in FSHD muscles with signs of disease activity, which correlated with the extent of intramuscular fibrosis. In addition, the accumulation of non-myogenic mesenchymal cells was higher in FSHD muscles that deteriorate more rapidly. Our results prompt a direct association between an accumulation, as well as an altered differentiation, of non-myogenic mesenchymal cells with muscle degeneration in FSHD patients. Elucidating the mechanisms and cellular interactions that are altered in the affected muscles of FSHD patients could be instrumental to clarify disease pathogenesis and identifying reliable novel therapeutic targets.


Assuntos
Células-Tronco Mesenquimais , Distrofia Muscular Facioescapuloumeral , Diferenciação Celular/fisiologia , Humanos , Imageamento por Ressonância Magnética/métodos , Células-Tronco Mesenquimais/patologia , Músculo Esquelético/metabolismo , Distrofia Muscular Facioescapuloumeral/genética , Distrofia Muscular Facioescapuloumeral/metabolismo , Distrofia Muscular Facioescapuloumeral/patologia
6.
Int J Mol Sci ; 23(16)2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-36012749

RESUMO

In the last 20 years, bone regenerative research has experienced exponential growth thanks to the discovery of new nanomaterials and improved manufacturing technologies that have emerged in the biomedical field. This revolution demands standardization of methods employed for biomaterials characterization in order to achieve comparable, interoperable, and reproducible results. The exploited methods for characterization span from biophysics and biochemical techniques, including microscopy and spectroscopy, functional assays for biological properties, and molecular profiling. This review aims to provide scholars with a rapid handbook collecting multidisciplinary methods for bone substitute R&D and validation, getting sources from an up-to-date and comprehensive examination of the scientific landscape.


Assuntos
Medicina Regenerativa , Engenharia Tecidual , Materiais Biocompatíveis/química , Regeneração Óssea , Osso e Ossos , Ciência dos Materiais , Medicina Regenerativa/métodos , Engenharia Tecidual/métodos
7.
Genes (Basel) ; 13(7)2022 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-35885943

RESUMO

Craniosynostosis are a heterogeneous group of genetic conditions characterized by the premature fusion of the skull bones. The most common forms of craniosynostosis are Crouzon, Apert and Pfeiffer syndromes. They differ from each other in various additional clinical manifestations, e.g., syndactyly is typical of Apert and rare in Pfeiffer syndrome. Their inheritance is autosomal dominant with incomplete penetrance and one of the main genes responsible for these syndromes is FGFR2, mapped on chromosome 10, encoding fibroblast growth factor receptor 2. We report an FGFR2 gene variant in a mother and daughter who present with different clinical features of Crouzon syndrome. The daughter is more severely affected than her mother, as also verified by a careful study of the face and oral cavity. The c.1032G>A transition in exon 8, already reported as a synonymous p.Ala344 = variant in Crouzon patients, also activates a new donor splice site leading to the loss of 51 nucleotides and the in-frame removal of 17 amino acids. We observed lower FGFR2 transcriptional and translational levels in the daughter compared to the mother and healthy controls. A preliminary functional assay and a molecular modeling added further details to explain the discordant phenotype of the two patients.


Assuntos
Acrocefalossindactilia , Craniossinostoses , Acrocefalossindactilia/genética , Craniossinostoses/genética , Feminino , Humanos , Mães , Fenótipo , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética
8.
Genes (Basel) ; 13(5)2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-35627201

RESUMO

Craniosynostosis (CS) is a major birth defect in which one or more skull sutures fuse prematurely. We previously performed a genome-wide association study (GWAS) for sagittal non-syndromic CS (sNCS), identifying associations downstream from BMP2 on 20p12.3 and intronic to BBS9 on 7p14.3; analyses of imputed variants in DLG1 on 3q29 were also genome-wide significant. We followed this work with a GWAS for metopic non-syndromic NCS (mNCS), discovering a significant association intronic to BMP7 on 20q13.31. In the current study, we sequenced the associated regions on 3q29, 7p14.3, and 20p12.3, including two candidate genes (BMP2 and BMPER) near some of these regions in 83 sNCS child-parent trios, and sequenced regions on 7p14.3 and 20q13.2-q13.32 in 80 mNCS child-parent trios. These child-parent trios were selected from the original GWAS cohorts if the probands carried at least one copy of the top associated GWAS variant (rs1884302 C allele for sNCS; rs6127972 T allele for mNCS). Many of the variants sequenced in these targeted regions are strongly predicted to be within binding sites for transcription factors involved in craniofacial development or bone morphogenesis. Variants enriched in more than one trio and predicted to be damaging to gene function are prioritized for functional studies.


Assuntos
Craniossinostoses , Estudo de Associação Genômica Ampla , Alelos , Proteínas de Transporte/genética , Craniossinostoses/genética , Humanos
9.
Int J Mol Sci ; 23(6)2022 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-35328476

RESUMO

Fracture non-union is a challenging orthopaedic issue and a socio-economic global burden. Several biological therapies have been introduced to improve traditional surgical approaches. Among these, the latest research has been focusing on adipose tissue as a powerful source of mesenchymal stromal cells, namely, adipose-derived stem cells (ADSCs). ADSC are commonly isolated from the stromal vascular fraction (SVF) of liposuctioned hypodermal adipose tissue, and their applications have been widely investigated in many fields, including non-union fractures among musculoskeletal disorders. This review aims at providing a comprehensive update of the literature on clinical application of ADSCs for the treatment of non-unions in humans. The study was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Only three articles met our inclusion criteria, with a total of 12 cases analyzed for demographics and harvesting, potential manufacturing and implantation of ADSCs. The review of the literature suggests that adipose derived cell therapy can represent a promising alternative in bone regenerative medicine for the enhancement of non-unions and bone defects. The low number of manuscripts reporting ADSC-based therapies for long bone fracture healing suggests some critical issues that are discussed in this review. Nevertheless, further investigations on human ADSC therapies are needed to improve the knowledge on their translational potential and to possibly achieve a consensus on their use for such applications.


Assuntos
Tecido Adiposo , Células-Tronco Mesenquimais , Adipócitos , Terapia Baseada em Transplante de Células e Tecidos , Humanos , Medicina Regenerativa
10.
Sci Rep ; 11(1): 21316, 2021 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-34716352

RESUMO

RUNX2 encodes the master bone transcription factor driving skeletal development in vertebrates, and playing a specific role in craniofacial and skull morphogenesis. The anatomically modern human (AMH) features sequence changes in the RUNX2 locus compared with archaic hominins' species. We aimed to understand how these changes may have contributed to human skull globularization occurred in recent evolution. We compared in silico AMH and archaic hominins' genomes, and used mesenchymal stromal cells isolated from skull sutures of craniosynostosis patients for in vitro functional assays. We detected 459 and 470 nucleotide changes in noncoding regions of the AMH RUNX2 locus, compared with the Neandertal and Denisovan genomes, respectively. Three nucleotide changes in the proximal promoter were predicted to alter the binding of the zinc finger protein Znf263 and long-distance interactions with other cis-regulatory regions. By surface plasmon resonance, we selected nucleotide substitutions in the 3'UTRs able to affect miRNA binding affinity. Specifically, miR-3150a-3p and miR-6785-5p expression inversely correlated with RUNX2 expression during in vitro osteogenic differentiation. The expression of two long non-coding RNAs, AL096865.1 and RUNX2-AS1, within the same locus, was modulated during in vitro osteogenic differentiation and correlated with the expression of specific RUNX2 isoforms. Our data suggest that RUNX2 may have undergone adaptive phenotypic evolution caused by epigenetic and post-transcriptional regulatory mechanisms, which may explain the delayed suture fusion leading to the present-day globular skull shape.


Assuntos
Evolução Biológica , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Crânio/anatomia & histologia , Animais , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Suturas Cranianas/crescimento & desenvolvimento , Craniossinostoses/genética , Epigênese Genética , Genoma Humano , Hominidae/anatomia & histologia , Hominidae/genética , Humanos , Células-Tronco Mesenquimais , MicroRNAs/genética , Homem de Neandertal/anatomia & histologia , Homem de Neandertal/genética , Osteogênese/genética , RNA Longo não Codificante/genética
11.
Genes (Basel) ; 12(7)2021 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-34356089

RESUMO

Craniosynostosis (CS) is the second most prevalent inborn craniofacial malformation; it results from the premature fusion of cranial sutures and leads to dimorphisms of variable severity. CS is clinically heterogeneous, as it can be either a sporadic isolated defect, more frequently, or part of a syndromic phenotype with mendelian inheritance. The genetic basis of CS is also extremely heterogeneous, with nearly a hundred genes associated so far, mostly mutated in syndromic forms. Several genes can be categorised within partially overlapping pathways, including those causing defects of the primary cilium. The primary cilium is a cellular antenna serving as a signalling hub implicated in mechanotransduction, housing key molecular signals expressed on the ciliary membrane and in the cilioplasm. This mechanical property mediated by the primary cilium may also represent a cue to understand the pathophysiology of non-syndromic CS. In this review, we aimed to highlight the implication of the primary cilium components and active signalling in CS pathophysiology, dissecting their biological functions in craniofacial development and in suture biomechanics. Through an in-depth revision of the literature and computational annotation of disease-associated genes we categorised 18 ciliary genes involved in CS aetiology. Interestingly, a prevalent implication of midline sutures is observed in CS ciliopathies, possibly explained by the specific neural crest origin of the frontal bone.


Assuntos
Cílios/fisiologia , Craniossinostoses/fisiopatologia , Mecanotransdução Celular/fisiologia , Cílios/genética , Ciliopatias/genética , Ciliopatias/fisiopatologia , Suturas Cranianas/metabolismo , Anormalidades Craniofaciais/fisiopatologia , Craniossinostoses/genética , Humanos , Crista Neural/metabolismo , Osteogênese/genética , Fenótipo , Transdução de Sinais/fisiologia
12.
Cells ; 10(7)2021 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-34359865

RESUMO

Autologous tissue-assisted regenerative procedures have been considered effective to close different types of fistula, including the leakage around tracheoesophageal puncture. The aim of this study was to retrospectively review 10 years of lipotransfer for persistent periprosthetic leakage in laryngectomized patients with voice prosthesis. Clinical records of patients who experienced periprosthetic leakage from December 2009 to December 2019 were reviewed. Patients receiving fat grafting were included. The leakage around the prosthesis was assessed with a methylene blue test. Twenty patients experiencing tracheoesophageal fistula enlargement were treated with fat grafting. At the one-month follow-up, all patients were considered improved with no leakage observed. At six months, a single injection was sufficient to solve 75% of cases (n 15), whereas 25% (n 5) required a second procedure. The overall success rate was 80% (n 16). Results remained stable for a follow-up of 5.54 ± 3.97 years. Fat grafting performed around the voice prosthesis, thanks to its volumetric and regenerative properties, is a valid and lasting option to solve persistent periprosthetic leakage.


Assuntos
Falha de Prótese , Punções , Regeneração , Fístula Traqueoesofágica/fisiopatologia , Tecido Adiposo/citologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Laringe Artificial , Masculino , Pessoa de Meia-Idade , Células-Tronco/citologia
13.
Colloids Surf B Biointerfaces ; 207: 111989, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34303114

RESUMO

Hydrogels based on short peptide molecules are interesting biomaterials with wide present and prospective use in biotechnologies. A well-known possible drawback of these materials can be their limited mechanical performance. In order to overcome this problem, we prepared Fmoc-Phe3self-assembling peptides by a biocatalytic approach, and we reinforced the hydrogel with graphene oxide nanosheets. The formulation here proposed confers to the hydrogel additional physicochemical properties without hampering peptide self-assembly. We investigated in depth the effect of nanocarbon morphology on hydrogel properties (i.e. morphology, viscoelastic properties, stiffness, resistance to an applied stress). In view of further developments towards possible clinical applications, we have preliminarily tested the biocompatibility of the composites. Our results showed that the innovative hydrogel composite formulation based on FmocPhe3 and GO is a biomaterial with improved mechanical properties that appears suitable for the development of biotechnological applications.


Assuntos
Grafite , Hidrogéis , Peptídeos , Estudos Prospectivos
14.
J Pers Med ; 11(5)2021 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-33946634

RESUMO

Basic and preclinical research founded the progress of personalized medicine by providing a prodigious amount of integrated profiling data and by enabling the development of biomedical applications to be implemented in patient-centered care and cures. If the rapid development of genomics research boosted the birth of personalized medicine, further development in omics technologies has more recently improved our understanding of the functional genome and its relevance in profiling patients' phenotypes and disorders. Concurrently, the rapid biotechnological advancement in diverse research areas enabled uncovering disease mechanisms and prompted the design of innovative biological treatments tailored to individual patient genotypes and phenotypes. Research in stem cells enabled clarifying their role in tissue degeneration and disease pathogenesis while providing novel tools toward the development of personalized regenerative medicine strategies. Meanwhile, the evolving field of integrated omics technologies ensured translating structural genomics information into actionable knowledge to trace detailed patients' molecular signatures. Finally, neuroscience research provided invaluable models to identify preclinical stages of brain diseases. This review aims at discussing relevant milestones in the scientific progress of basic and preclinical research areas that have considerably contributed to the personalized medicine revolution by bridging the bench-to-bed gap, focusing on stem cells, omics technologies, and neuroscience fields as paradigms.

15.
J Funct Biomater ; 12(1)2021 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-33673516

RESUMO

Due to the extremely high incidence of lesions and diseases in aging population, it is critical to put all efforts into developing a successful implant for osteochondral tissue regeneration. Many of the patients undergoing surgery present osteochondral fissure extending until the subchondral bone (corresponding to a IV grade according to the conventional radiographic classification by Berndt and Harty). Therefore, strategies for functional tissue regeneration should also aim at healing the subchondral bone and joint interface, besides hyaline cartilage. With the ambition of contributing to solving this problem, several research groups have been working intensively on the development of tailored implants that could promote that complex osteochondral regeneration. These implants may be manufactured through a wide variety of processes and use a wide variety of (bio)materials. This review aimed to examine the state of the art regarding the challenges, advantages, and drawbacks of the current strategies for osteochondral regeneration. One of the most promising approaches relies on the principles of additive manufacturing, where technologies are used that allow for the production of complex 3D structures with a high level of control, intended and predefined geometry, size, and interconnected pores, in a reproducible way. However, not all materials are suitable for these processes, and their features should be examined, targeting a successful regeneration.

16.
Int J Mol Sci ; 21(17)2020 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-32878114

RESUMO

Recent evidence has shown that graphene quantum dots (GQDs) are capable of crossing the blood-brain barrier, the barrier that reduces cancer therapy efficacy. Here, we tested three alternative GQDs' surface chemistries on two neural lineages (glioblastoma cells and mouse cortical neurons). We showed that surface chemistry modulates GQDs' biocompatibility. When used in combination with the chemotherapeutic drug doxorubicin, GDQs exerted a synergistic effect on tumor cells, but not on neurons. This appears to be mediated by the modification of membrane permeability induced by the surface of GQDs. Our findings highlight that GQDs can be adopted as a suitable delivery and therapeutic strategy for the treatment of glioblastoma, by both directly destabilizing the cell membrane and indirectly increasing the efficacy of chemotherapeutic drugs.


Assuntos
Doxorrubicina/química , Doxorrubicina/farmacologia , Embrião de Mamíferos/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Grafite/química , Neurônios/efeitos dos fármacos , Pontos Quânticos , Animais , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacologia , Apoptose , Proliferação de Células , Embrião de Mamíferos/citologia , Glioblastoma/patologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/citologia , Células Tumorais Cultivadas
18.
Int J Mol Sci ; 21(12)2020 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-32575385

RESUMO

All skeletal bones house osteogenic stem cell niches, in which mesenchymal stromal cells (MSC) provide progenitors for tissue growth and regeneration. They have been widely studied in long bones formed through endochondral ossification. Limited information is available on the composition of the osteogenic niche in flat bones (i.e., skull vault bones) that develop through direct membranous ossification. Craniosynostosis (CS) is a congenital craniofacial defect due to the excessive and premature ossification of skull vault sutures. This study aimed at analysing the expression of GLI1, AXIN2 and THY1 in the context of the human skull vault, using nonsyndromic forms of CS (NCS) as a model to test their functional implication in the aberrant osteogenic process. The expression of selected markers was studied in NCS patients' calvarial bone specimens, to assess the in vivo location of cells, and in MSC isolated thereof. The marker expression profile was analysed during in vitro osteogenic differentiation to validate the functional implication. Our results show that GLI1 and AXIN2 are expressed in periosteal and endosteal locations within the osteogenic niche of human calvarial bones. Their expression is higher in MSC isolated from calvarial bones than in those isolated from long bones and tends to decrease upon osteogenic commitment and differentiation. In particular, AXIN2 expression was lower in cells isolated from prematurely fused sutures than in those derived from patent sutures of NCS patients. This suggests that AXIN2 could reasonably represent a marker for the stem cell population that undergoes depletion during the premature ossification process occurring in CS.


Assuntos
Proteína Axina/metabolismo , Biomarcadores/metabolismo , Craniossinostoses/metabolismo , Crânio/citologia , Proteína GLI1 em Dedos de Zinco/metabolismo , Proteína Axina/genética , Diferenciação Celular , Células Cultivadas , Craniossinostoses/genética , Regulação para Baixo , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Osteogênese , Cultura Primária de Células , Crânio/metabolismo , Nicho de Células-Tronco , Proteína GLI1 em Dedos de Zinco/genética
19.
Genet Med ; 22(9): 1498-1506, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32499606

RESUMO

PURPOSE: Enrichment of heterozygous missense and truncating SMAD6 variants was previously reported in nonsyndromic sagittal and metopic synostosis, and interaction of SMAD6 variants with a common polymorphism nearBMP2 (rs1884302) was proposed to contribute to inconsistent penetrance. We determined the occurrence of SMAD6 variants in all types of craniosynostosis, evaluated the impact of different missense variants on SMAD6 function, and tested independently whether rs1884302 genotype significantly modifies the phenotype. METHODS: We performed resequencing of SMAD6 in 795 unsolved patients with any type of craniosynostosis and genotyped rs1884302 in SMAD6-positive individuals and relatives. We examined the inhibitory activity and stability of SMAD6 missense variants. RESULTS: We found 18 (2.3%) different rare damaging SMAD6 variants, with the highest prevalence in metopic synostosis (5.8%) and an 18.3-fold enrichment of loss-of-function variants comparedwith gnomAD data (P < 10-7). Combined with eight additional variants, ≥20/26 were transmitted from an unaffected parent but rs1884302 genotype did not predict phenotype. CONCLUSION: Pathogenic SMAD6 variants substantially increase the risk of both nonsyndromic and syndromic presentations of craniosynostosis, especially metopic synostosis. Functional analysis is important to evaluate missense variants. Genotyping of rs1884302 is not clinically useful. Mechanisms to explain the remarkable diversity of phenotypes associated with SMAD6 variants remain obscure.


Assuntos
Craniossinostoses , Craniossinostoses/genética , Genótipo , Humanos , Mutação de Sentido Incorreto/genética , Penetrância , Fenótipo , Proteína Smad6/genética
20.
Artigo em Inglês | MEDLINE | ID: mdl-32523936

RESUMO

With recent advances in nanotechnology, graphene nanomaterials are being translated to applications in the fields of biosensing, medicine, and diagnostics, with unprecedented power. Graphene is a carbon allotrope derived from graphite exfoliation made of an extremely thin honeycomb of sp2 hybridized carbons. In comparison with the bulk materials, graphene and its water-soluble derivative graphene oxide have a smaller size suitable for diagnostic platform miniaturization as well as high surface area and consequently loading of a large number of biological probes. In this work, we propose a nanotechnological method for concentrating total RNA solution and/or enriching small RNA molecules. To this aim, we exploited the unique trapping effects of GO nanoflakes in the presence of divalent cations (i.e., calcium and magnesium) that make it flocculate and precipitate, forming complex meshes that are positively charged. Here, we demonstrated that GO traps can concentrate nucleic acids in the presence of divalent cations and that small RNAs can be selectively released from GO-magnesium traps. GO nano-concentrators will allow better analytical performance with samples available in small amounts and will increase the sensitivity of sequencing platforms by short RNA selection.

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