79 research outputs found
Agro-climate tools for a new climate-smart agriculture
The way we produce food must adapt to a variable and changing climate. And key to achieving this is to improve the link between climate information and agricultural practices, especially those of smallholder farmers in developing countries. ‘Agro-climate tools’ do just that and some are introduced here
Silent polymorphisms in the RYR1 gene do not\ud modify the phenotype of the p.4898 I>T\ud pathogenic mutation in central core disease:\ud a case report
Background: Central core disease is a congenital myopathy, characterized by presence of central core-like areas in\ud
muscle fibers. Patients have mild or moderate weakness, hypotonia and motor developmental delay. The disease is\ud
caused by mutations in the human ryanodine receptor gene (RYR1), which encodes a calcium-release channel.\ud
Since the RYR1 gene is huge, containing 106 exons, mutation screening has been limited to three ‘hot spots’, with\ud
particular attention to the C-terminal region. Recent next- generation sequencing methods are now identifying\ud
multiple numbers of variants in patients, in which interpretation and phenotype prevision is difficult.\ud
Case presentation: In a Brazilian Caucasian family, clinical, histopathological and molecular analysis identified a\ud
new case of central core disease in a 48-year female. Sanger sequencing of the C-terminal region of the RYR1\ud
gene identified two different missense mutations: c.14256 A > C polymorphism in exon 98 and c.14693 T > C in\ud
exon 102, which have already been described as pathogenic. Trans-position of the 2 mutations was confirmed\ud
because patient’s daughter, mother and sister carried only the exon 98’s mutation, a synonymous variant that was\ud
subsequently found in the frequency of 013–0,05 of alleles. Further next generation sequencing study of the whole\ud
RYR1 gene in the patient revealed the presence of additional 5 common silent polymorphisms in homozygosis and\ud
8 polymorphisms in heterozygosis.\ud
Conclusions: Considering that patient’s relatives showed no pathologic phenotype, and the phenotype presented\ud
by the patient is within the range observed in other central core disease patients with the same mutation, it was\ud
concluded that the c.14256 A > C polymorphism alone is not responsible for disease, and the associated additional\ud
silent polymorphisms are not acting as modifiers of the primary pathogenic mutation in the affected patient. The\ud
case described above illustrates the present reality where new methods for wide genome screening are becoming\ud
more accessible and able to identify a great variety of mutations and polymorphisms of unknown function in\ud
patients and their families.Fundação de Amparo a Pesquisa do Estado de São Paulo - Centro de Pesquisa, Inovação e Difusão (FAPESP-CEPID)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq-INCT)Associação Brasileira de Distrofia Muscular (ABDIM)CAPES-COFECU
Novel fibronectin mutations and expansion of the phenotype in spondylometaphyseal dysplasia with “corner fractures”
Heterozygous pathogenic variants in the FN1 gene, encoding fibronectin (FN), have recently been shown to be associated with a skeletal disorder in some individuals affected by spondylometaphyseal dysplasia with “corner fractures” (SMD-CF). The most striking feature characterizing SMD-CF is irregularly shaped metaphyses giving the appearance of “corner fractures”. An array of secondary features, including developmental coxa vara, ovoid vertebral bodies and severe scoliosis, may also be present. FN is an important extra cellular matrix component for bone and cartilage development. Here we report five patients affected by this subtype of SMD-CF caused by five novel FN1 missense mutations: p.Cys123Tyr, p.Cys169Tyr, p.Cys213Tyr, p.Cys231Trp and p.Cys258Tyr. All individuals shared a substitution of a cysteine residue, disrupting disulfide bonds in the FN type-I assembly domains located in the N-terminal assembly region. The abnormal metaphyseal ossification and “corner fracture” appearances were the most remarkable clinical feature in these patients. In addition, generalized skeletal fragility with low-trauma bilateral femoral fractures was identified in one patient. Interestingly, the distal femoral changes in this patient healed with skeletal maturation. Our report expands the phenotypic and genetic spectrum of the FN1-related SMD-CF and emphasizes the importance of FN in bone formation and possibly also in the maintenance of bone strength.Peer reviewe
Nemaline Myopathy in Brazilian Patients: Molecular and Clinical Characterization
Nemaline myopathy (NM), a structural congenital myopathy, presents a significant clinical and genetic heterogeneity. Here, we compiled molecular and clinical data of 30 Brazilian patients from 25 unrelated families. Next-generation sequencing was able to genetically classify all patients: sixteen families (64%) with mutation in NEB, five (20%) in ACTA1, two (8%) in KLHL40, and one in TPM2 (4%) and TPM3 (4%). In the NEB-related families, 25 different variants, 11 of them novel, were identified; splice site (10/25) and frame shift (9/25) mutations were the most common. Mutation c.24579 G>C was recurrent in three unrelated patients from the same region, suggesting a common ancestor. Clinically, the “typical” form was the more frequent and caused by mutations in the different NM genes. Phenotypic heterogeneity was observed among patients with mutations in the same gene. Respiratory involvement was very common and often out of proportion with limb weakness. Muscle MRI patterns showed variability within the forms and genes, which was related to the severity of the weakness. Considering the high frequency of NEB mutations and the complexity of this gene, NGS tools should be combined with CNV identification, especially in patients with a likely non-identified second mutation
Nemaline Myopathy in Brazilian Patients: Molecular and Clinical Characterization
Nemaline myopathy (NM), a structural congenital myopathy, presents a significant clinical and genetic heterogeneity. Here, we compiled molecular and clinical data of 30 Brazilian patients from 25 unrelated families. Next-generation sequencing was able to genetically classify all patients: sixteen families (64%) with mutation in NEB, five (20%) in ACTA1, two (8%) in KLHL40, and one in TPM2 (4%) and TPM3 (4%). In the NEB-related families, 25 different variants, 11 of them novel, were identified; splice site (10/25) and frame shift (9/25) mutations were the most common. Mutation c.24579 G>C was recurrent in three unrelated patients from the same region, suggesting a common ancestor. Clinically, the “typical” form was the more frequent and caused by mutations in the different NM genes. Phenotypic heterogeneity was observed among patients with mutations in the same gene. Respiratory involvement was very common and often out of proportion with limb weakness. Muscle MRI patterns showed variability within the forms and genes, which was related to the severity of the weakness. Considering the high frequency of NEB mutations and the complexity of this gene, NGS tools should be combined with CNV identification, especially in patients with a likely non-identified second mutation
Evidence-based Risk Stratification for Sport Medicine Procedures During the COVID-19 Pandemic
Orthopaedic practices have been markedly affected by the emergence of the COVID-19 pandemic. Despite the ban on elective procedures, it is impossible to define the medical urgency of a case solely on whether a case is on an elective surgery schedule. Orthopaedic surgical procedures should consider COVID-19-associated risks and an assimilation of all available disease dependent, disease independent, and logistical information that is tailored to each patient, institution, and region. Using an evidence-based risk stratification of clinical urgency, we provide a framework for prioritization of orthopaedic sport medicine procedures that encompasses such factors. This can be used to facilitate the risk-benefit assessment of the timing and setting of a procedure during the COVID-19 pandemic
Whole-genome sequencing of 1,171 elderly admixed individuals from Brazil
As whole-genome sequencing (WGS) becomes the gold standard tool for studying population genomics and medical applications, data on diverse non-European and admixed individuals are still scarce. Here, we present a high-coverage WGS dataset of 1,171 highly admixed elderly Brazilians from a census-based cohort, providing over 76 million variants, of which ~2 million are absent from large public databases. WGS enables identification of ~2,000 previously undescribed mobile element insertions without previous description, nearly 5 Mb of genomic segments absent from the human genome reference, and over 140 alleles from HLA genes absent from public resources. We reclassify and curate pathogenicity assertions for nearly four hundred variants in genes associated with dominantly-inherited Mendelian disorders and calculate the incidence for selected recessive disorders, demonstrating the clinical usefulness of the present study. Finally, we observe that whole-genome and HLA imputation could be significantly improved compared to available datasets since rare variation represents the largest proportion of input from WGS. These results demonstrate that even smaller sample sizes of underrepresented populations bring relevant data for genomic studies, especially when exploring analyses allowed only by WGS
Soluble iron nutrients in Saharan dust over the central Amazon rainforest
The intercontinental transport of aerosols from the Sahara desert plays a significant role in nutrient cycles in the Amazon rainforest, since it carries many types of minerals to these otherwise low-fertility lands. Iron is one of the micronutrients essential for plant growth, and its long-range transport might be an important source for the iron-limited Amazon rainforest. This study assesses the bioavailability of iron Fe(II) and Fe(III) in the particulate matter over the Amazon forest, which was transported from the Sahara desert (for the sake of our discussion, this term also includes the Sahel region). The sampling campaign was carried out above and below the forest canopy at the ATTO site (Amazon Tall Tower Observatory), a near-pristine area in the central Amazon Basin, from March to April 2015. Measurements reached peak concentrations for soluble Fe(III) (48 ng m−3), Fe(II) (16 ng m−3), Na (470 ng m−3), Ca (194 ng m−3), K (65 ng m−3), and Mg (89 ng m−3) during a time period of dust transport from the Sahara, as confirmed by ground-based and satellite remote sensing data and air mass backward trajectories. Dust sampled above the Amazon canopy included primary biological aerosols and other coarse particles up to 12 µm in diameter. Atmospheric transport of weathered Saharan dust, followed by surface deposition, resulted in substantial iron bioavailability across the rainforest canopy. The seasonal deposition of dust, rich in soluble iron, and other minerals is likely to assist both bacteria and fungi within the topsoil and on canopy surfaces, and especially benefit highly bioabsorbent species. In this scenario, Saharan dust can provide essential macronutrients and micronutrients to plant roots, and also directly to plant leaves. The influence of this input on the ecology of the forest canopy and topsoil is discussed, and we argue that this influence would likely be different from that of nutrients from the weathered Amazon bedrock, which otherwise provides the main source of soluble mineral nutrients
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