RESUMO
There is an increasing need for renewable energy sources to replace part of our fossil fuel-based economy and reduce greenhouse gas emission. Sugarcane bagasse is a prominent feedstock to produce cellulosic bioethanol, but strategies are still needed to improve the cost-effective exploitation of this potential energy source. In model plants, it has been shown that GUX genes are involved in cell wall hemicellulose decoration, adding glucuronic acid substitutions on the xylan backbone. Mutation of GUX genes increases enzyme access to cell wall polysaccharides, reducing biomass recalcitrance in Arabidopsis thaliana. Here, we characterized the sugarcane GUX genes and silenced GUX2 in commercial hybrid sugarcane. The transgenic lines had no penalty in development under greenhouse conditions. The sugarcane GUX1 and GUX2 enzymes generated different patterns of xylan glucuronidation, suggesting they may differently influence the molecular interaction of xylan with cellulose and lignin. Studies using biomass without chemical or steam pretreatment showed that the cell wall polysaccharides, particularly xylan, were less recalcitrant in sugarcane with GUX2 silenced than in WT plants. Our findings suggest that manipulation of GUX in sugarcane can reduce the costs of second-generation ethanol production and enhance the contribution of biofuels to lowering the emission of greenhouse gases.
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Arabidopsis , Saccharum , Celulose/metabolismo , Xilanos/química , Biomassa , Polissacarídeos , Arabidopsis/genética , Plantas/metabolismoRESUMO
Strokes affect up to 10% of children with sickle-cell disease (SCD). The most commonly used strategy to prevent a first-time stroke or its recurrence is to perform periodic red blood cell transfusions. This article aims to evaluate the quality of life (QoL) of children and adolescents with SCD undergoing a chronic transfusion regimen (CTR) for stroke prophylaxis, according to their caregivers' perception. A cross-sectional study was conducted using a sociodemographic interview with an application of a validated instrument (Pediatric Quality of Life Inventory) involving 16 caregivers of patients with SCD aged <18 years undergoing CTR in a reference center. The data were processed using STATA version 13.0. The caregivers were predominantly the mothers of the minors that were part of the study cohort (87.5%), an income of <2 minimum wages (81.2% of cases) and >8 years of schooling (56.2%). The patients had a mean age of 10.4 years, 68.8% were male, 75% were mixed-race and came from small towns and rural areas (68.8%). The overall mean QoL was 45.8 (95% confidence interval [CI] 42.5-49.2). Female patients and those aged <12 years had lower levels of overall QoL. The emotional dimension of the children was the least compromised as per the caregivers' perception. The mean QoL of children with SCD on a CTR is lower than the estimated global mean QoL reported in the literature. It is possible that the occurrence of a stroke enhances the caregivers' negative perceptions about the QoL of patients with SCD.
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Anemia Falciforme , Acidente Vascular Cerebral , Criança , Adolescente , Humanos , Masculino , Feminino , Qualidade de Vida/psicologia , Cuidadores/psicologia , Estudos Transversais , Anemia Falciforme/terapia , Acidente Vascular Cerebral/prevenção & controleRESUMO
BACKGROUND: Achondroplasia is the most common bone dysplasia associated with disproportionate short stature, and other comorbidities, such as foramen magnum stenosis, thoracolumbar kyphosis, lumbar hyperlordosis, genu varum and spinal compression. Additionally, patients affected with this condition have higher frequency of sleep disorders, ear infections, hearing loss and slowed development milestones. Considering these clinical features, we aimed to summarize the regional experts' recommendations for the multidisciplinary management of patients with achondroplasia in Latin America, a vast geographic territory with multicultural characteristics and with socio-economical differences of developing countries. METHODS: Latin American experts (from Argentina, Brazil, Chile and Colombia) particiáted of an Advisory Board meeting (October 2019), and had a structured discussion how patients with achondroplasia are followed in their healthcare centers and punctuated gaps and opportunities for regional improvement in the management of achondroplasia. RESULTS: Practical recommendations have been established for genetic counselling, prenatal diagnosis and planning of delivery in patients with achondroplasia. An outline of strategies was added as follow-up guidelines to specialists according to patient developmental phases, amongst them neurologic, orthopedic, otorhinolaryngologic, nutritional and anthropometric aspects, and related to development milestones. Additionally, the role of physical therapy, physical activity, phonoaudiology and other care related to the quality of life of patients and their families were discussed. Preoperative recommendations to patients with achondroplasia were also included. CONCLUSIONS: This study summarized the main expert recommendations for the health care professionals management of achondroplasia in Latin America, reinforcing that achondroplasia-associated comorbidities are not limited to orthopedic concerns.
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Acondroplasia , Cifose , Acondroplasia/diagnóstico , Acondroplasia/genética , Acondroplasia/terapia , Criança , Feminino , Aconselhamento Genético , Humanos , América Latina/epidemiologia , Qualidade de VidaRESUMO
Cu pollution is a problem in mining areas in Peru. Here we evaluate the phytoextraction capacity, physiological and proteomic responses of four species growing in copper-contaminated areas in Arequipa, Peru. The plants used in the experiments were obtained by collecting seedlings (Tessaria integrifolia, Bacharis salicifolia), rhizomes (Eleocharis montevidensis) and seeds (Chenopodium murale) along a polluted river. They were exposed to solutions containing 2, 4, 8, 16 and 32 mg Cu L-1 during 20 days. Growth was affected in a concentration-dependent way. According to the tolerance index, B. salicifolia and C. murale were the most sensitive species, but with greater Cu phytoextraction capacity and accumulation in the biomass. The content and ratio of photosynthetic pigments changed differently for each specie and carotenoids level were less affected than chlorophyll. Cu also induced changes in the protein and sugar contents. Antioxidant enzyme activities (catalase and superoxide dismutase) increased with a decrease in the malondialdehyde. There were marked changes in the protein 2D-PAGE profiles with an increase in the abundance of metallothioneins (MT) of class II type I and II. Our results suggest that these species can grow in Cu polluted areas because they developed multiple tolerance mechanisms, such as and MTs production seems a important one.
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Adaptação Biológica/efeitos dos fármacos , Cobre/toxicidade , Poluentes Ambientais/toxicidade , Metalotioneína/metabolismo , Desenvolvimento Vegetal/efeitos dos fármacos , Poluentes do Solo/toxicidade , Antioxidantes/metabolismo , Biodegradação Ambiental , Biomassa , Clorofila/metabolismo , Cobre/metabolismo , Poluentes Ambientais/metabolismo , Mineração , Peru , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Proteômica , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Poluentes do Solo/metabolismo , Especificidade da EspécieRESUMO
KEY MESSAGE: A sugarcane MYB present in the culm induces suberin biosynthesis and is involved both with fatty acid and phenolics metabolism. Few transcription factors have been described as regulators of cell wall polymers deposition in C4 grasses. Particularly, regulation of suberin biosynthesis in this group of plants remains poorly understood. Here, we showed that the sugarcane MYB transcription factor ShMYB78 is an activator of suberin biosynthesis and deposition. ShMYB78 was identified upon screening genes whose expression was upregulated in sugarcane internodes undergoing suberization during culm development or triggered by wounding. Agrobacterium-mediated transient expression of ShMYB78 in Nicotiana benthamiana leaves induced the ectopic deposition of suberin and its aliphatic and aromatic monomers. Further, the expression of suberin-related genes was induced by ShMYB78 heterologous expression in Nicotiana benthamiana leaves. ShMYB78 was shown to be a nuclear protein based on its presence in sugarcane internode nuclear protein extracts, and protoplast transactivation assays demonstrated that ShMYB78 activates the promoters of the sugarcane suberin biosynthetic genes ß-ketoacyl-CoA synthase (ShKCS20) and caffeic acid-O-methyltransferase (ShCOMT). Our results suggest that ShMYB78 may be involved in the transcriptional regulation of suberin deposition, from fatty acid metabolism to phenylpropanoid biosynthesis, in sugarcane internodes.
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Lipídeos/biossíntese , Nicotiana/metabolismo , Proteínas de Plantas/genética , Saccharum/genética , Fatores de Transcrição/genética , Núcleo Celular , Regulação da Expressão Gênica de Plantas , Lipídeos/genética , Filogenia , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Nicotiana/genética , Fatores de Transcrição/metabolismoRESUMO
Identification of variants in the acid α-glucosidase (GAA) gene in Pompe disease provides valuable insights and systematic overviews are needed. We report on the number, nature, frequency, and geographic distribution of GAA sequence variants listed in the Pompe Registry, a long-term, observational program and the largest global repository of Pompe disease data. Variant information was reviewed and compared with publicly available GAA databases/resources. Among 1,079 eligible patients, 2,075 GAA variants (80 unique novel) were reported. Variants were listed by groups representing Pompe disease phenotypes. Patients were classified as Group A: Symptom onset ≤ 12 months of age with cardiomyopathy; Group B: Symptom onset ≤ 12 years of age (includes patients with symptom onset ≤ 12 months of age without cardiomyopathy); or Group C: Symptom onset > 12 years of age. Likely impact of novel variants was predicted using bioinformatics algorithms. Variants were classified by pathogenicity using ACMG guidelines. Data reported from the Pompe Registry provide new information about the distribution of GAA variants globally and across the clinical spectrum, add to the number and diversity of GAA variants registered in public databases through published data sharing, provide a first indication of the severity of novel variants, and assist in diagnostic practice and outcome prediction.
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Estudos de Associação Genética , Predisposição Genética para Doença , Doença de Depósito de Glicogênio Tipo II/genética , Mutação , Fenótipo , alfa-Glucosidases/genética , Alelos , Bases de Dados Genéticas , Estudos de Associação Genética/métodos , Loci Gênicos , Variação Genética , Genótipo , Saúde Global , Doença de Depósito de Glicogênio Tipo II/diagnóstico , Doença de Depósito de Glicogênio Tipo II/epidemiologia , Humanos , Sistema de RegistrosRESUMO
BACKGROUND: Sugarcane is a tropical crop that can accumulate high concentration of sucrose in the stem as a storage carbohydrate. For that reason, sugarcane accounts for approximately 75% of all the sugar produced in the world and has become the main sugar source to produce first-generation bioethanol in Brazil. Daily rhythms cause plants to adapt and coordinate their metabolism to achieve maximum photosynthesis and carbohydrate production throughout the day. Circadian rhythms arise from the interaction of an internal oscillator and external stimuli, whereas diel rhythms occur in response to a light-dark cycle. Diel signalling contributes to synchronizing circadian rhythms to photoperiods, and levels of carbohydrates oscillate in a diel fashion. Under regular photoperiods, they are synthesized during the daytime and consumed throughout the night as an energy reserve. However, short days can induce higher rates of synthesis during daytime and lower rates of consumption in the dark. Cell wall carbohydrates are also diurnally regulated, and it has been shown that celluloses, hemicelluloses and pectin are deposited/degraded at different times of the day. To assess the diel carbohydrate profile in young sugarcane plants, we measured soluble sugars and cell wall components along a time course in plants subjected either to a regular day or short day. RESULTS: Short-day influenced sucrose synthesis and cell wall components. In short-day a 44% increase in sucrose concentration was detected in the dark, but was stable during the day. Cellulose, hemicellulose and pectin also fluctuate within a 24 h interval when subjected to a short day. A 38% increase in leaf sheath cellulose was observed from the middle of the day to the first hour of the night. Leaf sheath pectin and hemicellulose also increased from the day to the night, while it decreased in leaves. CONCLUSIONS: The presented data show diurnal patterns of soluble sugar metabolism together with temporal regulation of cell wall metabolism for a short day, suggesting that diel signalling has a role in how sugarcane manages sugar accumulation and partitioning. Understanding cell wall synthesis/degradation dynamics may help to improve the yield of sugarcane.
Assuntos
Parede Celular/metabolismo , Ritmo Circadiano/fisiologia , Fotoperíodo , Saccharum/fisiologia , Açúcares/metabolismo , Pectinas/metabolismo , Polissacarídeos/metabolismoRESUMO
Saccharum spontaneum has been used for the development of energy cane a crop aimed to be used for the production of second-generation ethanol, or lignocellulosic ethanol. Lignin is a main challenge in the conversion of cell wall sugars into ethanol. In our studies to isolate the genes the lignin biosynthesis in S. spontaneum we have had great difficulty in RT-PCR reactions. Thus, we evaluated the effectiveness of different additives in the amplification of these genes. While COMT and CCoAOMT genes did not need any additives for other genes there was no amplification (HCT, F5H, 4CL and CCR) or the yield was very low (CAD and C4H). The application of supplementary cDNA was enough to overcome the non-specificity and low yield for C4H and C3H, while the addition of 0.04% BSA + 2% formamide was effective to amplify 4CL, CCR, F5H and CCR. HCT was amplified only by addition of 0.04% BSA + 2% formamide + 0.1 M trehalose and amplification of PAL was possible with addition of 2% of DMSO. Besides optimization of expression assays, the results show that additives can act independently or synergistically.
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Regulação da Expressão Gênica de Plantas/genética , Lignina/genética , Técnicas de Amplificação de Ácido Nucleico/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Saccharum/genética , Parede Celular/genética , Primers do DNA , Etanol , Lignina/biossíntese , Metiltransferases/genéticaRESUMO
Sugar cane is an important crop for sugar and biofuel production. Its lignocellulosic biomass represents a promising option as feedstock for second-generation ethanol production. Nitrogen fertilization can affect differently tissues and its biopolymers, including the cell-wall polysaccharides and lignin. Lignin content and composition are the most important factors associated with biomass recalcitrance to convert cell-wall polysaccharides into fermentable sugars. Thus it is important to understand the metabolic relationship between nitrogen fertilization and lignin in this feedstock. In this study, a large-scale proteomics approach based on GeLC-MS/MS was employed to identify and relatively quantify proteins differently accumulated in two contrasting genotypes for lignin composition after excessive nitrogen fertilization. From the â¼1000 nonredundant proteins identified, 28 and 177 were differentially accumulated in response to nitrogen from IACSP04-065 and IACSP04-627 lines, respectively. These proteins were associated with several functional categories, including carbon metabolism, amino acid metabolism, protein turnover, and oxidative stress. Although nitrogen fertilization has not changed lignin content, phenolic acids and lignin composition were changed in both species but not in the same way. Sucrose and reducing sugars increased in plants of the genotype IACSP04-065 receiving nitrogen.
Assuntos
Biocombustíveis , Plantas Geneticamente Modificadas/genética , Proteoma/genética , Saccharum/genética , Biomassa , Carboidratos/química , Carboidratos/genética , Fermentação , Regulação da Expressão Gênica de Plantas , Genótipo , Lignina/química , Lignina/metabolismo , Nitrogênio/química , Nitrogênio/metabolismo , Oxidantes/química , Oxidantes/metabolismo , Fenótipo , Plantas Geneticamente Modificadas/metabolismo , Proteoma/química , Saccharum/metabolismoRESUMO
Holoprosencephaly (HPE) is a spectrum of brain and facial malformations primarily reflecting genetic factors, such as chromosomal abnormalities and gene mutations. Here, we present a clinical and molecular analysis of 195 probands with HPE or microforms; approximately 72% of the patients were derived from the Latin American Collaborative Study of Congenital Malformations (ECLAMC), and 82% of the patients were newborns. Alobar HPE was the predominant brain defect in almost all facial defect categories, except for patients without oral cleft and median or lateral oral clefts. Ethmocephaly, cebocephaly, and premaxillary agenesis were primarily observed among female patients. Premaxillary agenesis occurred in six of the nine diabetic mothers. Recurrence of HPE or microform was approximately 19%. The frequency of microdeletions, detected using Multiplex Ligation-dependant Probe Amplification (MLPA) was 17% in patients with a normal karyotype. Cytogenetics or QF-PCR analyses revealed chromosomal anomalies in 27% of the probands. Mutational analyses in genes SHH, ZIC2, SIX3 and TGIF were performed in 119 patients, revealing eight mutations in SHH, two mutations in SIX3 and two mutations in ZIC2. Thus, a detailed clinical description of new HPE cases with identified genetic anomalies might establish genotypic and phenotypic correlations and contribute to the development of additional strategies for the analysis of new cases.
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The agricultural sugarcane residues, bagasse and straws, can be used for second-generation ethanol (2GE) production by the cellulose conversion into glucose (saccharification). However, the lignin content negatively impacts the saccharification process. This polymer is mainly composed of guaiacyl (G), hydroxyphenyl (H), and syringyl (S) units, the latter formed in the ferulate 5-hydroxylase (F5H) branch of the lignin biosynthesis pathway. We have generated transgenic lines overexpressing ShF5H1 under the control of the C4H (cinnamate 4-hydroxylase) rice promoter, which led to a significant increase of up to 160% in the S/G ratio and 63% in the saccharification efficiency in leaves. Nevertheless, the content of lignin was unchanged in this organ. In culms, neither the S/G ratio nor sucrose accumulation was altered, suggesting that ShF5H1 overexpression would not affect first-generation ethanol production. Interestingly, the bagasse showed a significantly higher fiber content. Our results indicate that the tissue-specific manipulation of the biosynthetic branch leading to S unit formation is industrially advantageous and has established a foundation for further studies aiming at refining lignin modifications. Thus, the ShF5H1 overexpression in sugarcane emerges as an efficient strategy to improve 2GE production from straw.
Assuntos
Lignina , Saccharum , Lignina/química , Lignina/metabolismo , Saccharum/genética , Saccharum/química , Saccharum/metabolismo , Oxigenases de Função Mista/metabolismo , Transcinamato 4-Mono-Oxigenase/metabolismo , Etanol/metabolismoRESUMO
Cartilage-hair hypoplasia syndrome (CHH) is an autosomal recessive disorder frequently linked to n.72A>G (previously known as n.70A>G and n.71A>G), the most common RMRP variant worldwide. More than 130 pathogenic variants in this gene have already been described associated with CHH, and founder alterations were reported in the Finnish and Japanese populations. Our previous study in Brazilian CHH patients showed a high prevalence of n.197C>T variant (former n.195C>T and n.196C>T) when compared to other populations. The aim of this study was to investigate a possible founder effect of the n.197C>T variant in the RMRP gene in a series of CHH Brazilian patients. We have selected four TAG SNPs within chromosome 9 and genotyped the probands and their parents (23 patients previously described and nine novel). A common haplotype to the n.197C>T variant carriers was identified. Patients were also characterized for 46 autosomal Ancestry Informative Markers (AIMs). European ancestry was the most prevalent (58%), followed by African (24%) and Native American (18%). Our results strengthen the hypothesis of a founder effect for the n.197C>T variant in Brazil and indicate that this variant in the RMRP gene originated from a single event on chromosome 9 with a possible European origin.
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Efeito Fundador , Cabelo , Doença de Hirschsprung , Osteocondrodisplasias , Polimorfismo de Nucleotídeo Único , Humanos , Brasil , Doença de Hirschsprung/genética , Masculino , Osteocondrodisplasias/genética , Osteocondrodisplasias/congênito , Feminino , Cabelo/anormalidades , RNA Longo não Codificante/genética , Haplótipos , Doenças da Imunodeficiência Primária/genética , Hipotricose/genética , Cromossomos Humanos Par 9/genética , CriançaRESUMO
BACKGROUND: Chronic respiratory insufficiency from progressive muscle weakness causes morbidity and mortality in late-onset Pompe disease (LOPD). Previous Pompe Registry (NCT00231400) analyses for ≤ 5 years' alglucosidase alfa treatment showed a single linear time trend of stable forced vital capacity (FVC) % predicted. METHODS: To assess longer term Pompe Registry data, piecewise linear mixed model regression analyses estimated FVC% predicted trajectories in invasive-ventilator-free patients with LOPD aged ≥ 5 years. We estimated annual FVC change 0-6 months, > 6 months-5 years, and > 5-13 years from treatment initiation, adjusting for baseline age, sex, and non-invasive ventilation. FINDINGS: Among 485 patients (4612 FVC measurements; 8.3 years median follow-up), median ages at symptom onset, diagnosis, and alglucosidase alfa initiation were 34.3, 41.1, and 44.9 years, respectively. FVC% increased during the first 6 months' treatment (slope 1.83%/year; 95% confidence interval: 0.66, 3.01; P = 0.0023), then modestly declined -0.54%/year (-0.79, -0.30; P < 0.0001) during > 6 months-5 years, and -1.00%/year (-1.36, -0.63; P < 0.0001) during > 5-13 years. The latter two periods' slopes were not significantly different from each other (Pdifference = 0.0654) and were less steep than published natural history slopes (-1% to -4.6%/year). Estimated individual slopes were ≥ 0%/year in 96.1%, 30.3%, and 13.2% of patients during the 0-6 month, > 6 month-5 year, and > 5-13 year periods, respectively. CONCLUSION: These real-world data indicate an alglucosidase alfa benefit on FVC trajectory that persists at least 13 years compared with published natural history data. Nevertheless, unmet need remains since most individuals demonstrate lung function decline 5 years after initiating treatment. Whether altered FVC trajectory impacts respiratory failure incidence remains undetermined. TRIAL REGISTRATION: This study was registered (NCT00231400) on ClinicalTrials.gov on September 30, 2005, retrospectively registered.
Assuntos
Doença de Depósito de Glicogênio Tipo II , Sistema de Registros , alfa-Glucosidases , Humanos , Doença de Depósito de Glicogênio Tipo II/tratamento farmacológico , Doença de Depósito de Glicogênio Tipo II/fisiopatologia , Masculino , Feminino , alfa-Glucosidases/uso terapêutico , Adulto , Capacidade Vital/efeitos dos fármacos , Capacidade Vital/fisiologia , Pessoa de Meia-Idade , Terapia de Reposição de Enzimas/métodos , Adulto Jovem , Adolescente , Criança , Seguimentos , Pré-EscolarRESUMO
BACKGROUND: Mucopolysaccharidosis type VI (MPS VI) is a progressive, chronic and multisystem lysosomal storage disease with a wide disease spectrum. Clinical and biochemical improvements have been reported for MPS VI patients on enzyme replacement therapy (ERT) with rhASB (recombinant human arylsulfatase B; galsulfase, Naglazyme®, BioMarin Pharmaceutical Inc.), making early diagnosis and intervention imperative for optimal patient outcomes. Few studies have included children younger than five years of age. This report describes 34 MPS VI patients that started treatment with galsulfase before five years of age. METHODS: Data from patients who initiated treatment at <5 years of age were collected from patients' medical records. Baseline and follow-up assessments of common symptoms that led to diagnosis and that were used to evaluate disease progression and treatment efficacy were evaluated. RESULTS: A significant negative correlation was seen with treatment with ERT and urinary GAG levels. Of those with baseline and follow-up growth data, 47% remained on their pre-treatment growth curve or moved to a higher percentile after treatment. Of the 9 patients with baseline and follow-up sleep studies, 5 remained unaffected and 1 patient initially with mild sleep apnea showed improvement. Data regarding cardiac, ophthalmic, central nervous system, hearing, surgical interventions and development are also reported. No patient discontinued treatment due to an adverse event and all that were treatment-emergent resolved. CONCLUSIONS: The prescribed dosage of 1mg/kg IV weekly with galsulfase ERT is shown to be safe and effective in slowing and/or improving certain aspects of the disease, although patients should be closely monitored for complications associated with the natural history of the disease, especially cardiac valve involvement and spinal cord compression. A long-term follow-up investigation of this group of children will provide further information on the benefits of early treatment as well as disease progression and treatment efficacy and safety in this young patient population.
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Terapia de Reposição de Enzimas , Mucopolissacaridose VI/terapia , N-Acetilgalactosamina-4-Sulfatase/genética , Pré-Escolar , Terapia de Reposição de Enzimas/efeitos adversos , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Masculino , Mucopolissacaridose VI/enzimologia , Mucopolissacaridose VI/genética , N-Acetilgalactosamina-4-Sulfatase/efeitos adversos , N-Acetilgalactosamina-4-Sulfatase/metabolismo , N-Acetilgalactosamina-4-Sulfatase/uso terapêutico , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/genética , Proteínas Recombinantes/uso terapêuticoRESUMO
Introduction: Pathogenic variants in the SLC26A2/DTDST gene cause the following spectrum of phenotypes: achondrogenesis 1B (ACG1B), atelosteogenesis 2 (AO2), diastrophic dysplasia (DTD), and recessive-multiple epiphyseal dysplasia (rMED), the first 2 being lethal. Here, we report a cohort and a comprehensive literature review on a genotype-phenotype correlation of SLC26A2/DTDST-related disorders. Methods: The local patients were genotyped by Sanger sequencing or next-generation sequencing (NGS). We reviewed data from the literature regarding phenotype, zygosity, and genotype in parallel. Results: The local cohort enrolled 12 patients, including one with a Desbuquois-like phenotype. All but one showed biallelic mutations, however, only one allele mutated in a fetus presenting ACG1B was identified. The literature review identified 42 articles and the analyses of genotype and zygosity included the 12 local patients. Discussion: The R279W variant was the most prevalent among the local patients. It was in homozygosity (hmz) in 2 patients with rMED and in compound heterozygosity (chtz) in 9 patients. The genotype and zygosity review of all patients led to the following conclusions: DTD is the most common phenotype in Finland due to a Finnish mutation (c.727-1G>C). Outside of Finland, rMED is the most prevalent phenotype, usually associated with R279W in hmz. In contrast, DTD's genotype is usually in chtz. Despite a large number of variants (38), just 8 are recurrent (R279W, C653S, c.-26+2T>C, R178*, K575Sfs*10, V340del, G663R, T512K). The last 3 in hmz lead to lethal phenotypes. The Finnish mutation is found only in chtz outside of Finland, being associated with all 4 classical phenotypes. The p.R178* and p.K575Sfs*10 variants should be viewed as lethal mutations since both were mainly described with lethal phenotypes and were never reported in hmz. The existence of 9 patients with only one mutated allele suggests that other mutations in the other allele of these patients still need to be unveiled.
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BACKGROUND: Studies indicate that doses of alglucosidase alfa (ALGLU) higher than label dose (20 mg/kg every other week) improve clinical outcomes in infantile-onset Pompe disease (IOPD). We investigated data from the Pompe Registry to determine the association between ALGLU dose and survival in IOPD. RESULTS: We included 332 IOPD patients from the Registry as of January 2022 who had cardiomyopathy and were first treated at age < 1 year. We used Cox proportional hazards models to estimate hazard ratios (HR) and 95% confidence intervals (CI) for the association between ALGLU as a time-varying exposure and survival, adjusting for age at first treatment, sex, and cross-reactive immunologic material (CRIM)/immune tolerance induction (ITI) status. Dose was measured as average relative dose received over time (in multiples of label dose, range > 0 to 4 times label dose), current dose, and lagged dose. 81% patients received label dose at treatment initiation. Over time, 52% received a higher dose. Higher ALGLU dose over time was associated with improved survival: adjusted HR 0.40 (95% CI 0.22-0.73, p = 0.003) per 1-unit increase in average relative dose, with similar results for invasive ventilation-free survival (adjusted HR 0.48, 95% CI 0.28-0.84; p = 0.010). The association was consistent in patients first treated before or after 3 months of age and did not vary significantly by CRIM status. Results for current and lagged dose were similar to average dose. CONCLUSIONS: Higher ALGLU doses were associated with significantly improved overall and invasive ventilator-free survival in IOPD. Results were consistent across sensitivity analyses.
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Doença de Depósito de Glicogênio Tipo II , Humanos , Doença de Depósito de Glicogênio Tipo II/tratamento farmacológico , alfa-Glucosidases/uso terapêutico , Sistema de Registros , Terapia de Reposição de Enzimas/métodosRESUMO
Hunter disease or mucopolysaccharidosis type II (MPS II) is an X-linked recessive lysosomal disorder caused by the deficiency of iduronate-2-sulfatase, which is involved in the catabolism of the glycosaminoglycans (GAGs) heparan and dermatan sulphate. Our aim was to analyze three patients with severe Hunter syndrome that showed a total deletion of the iduronate-2-sulphatase (IDS) gene, after exon by exon PCR. DNA was used as a template for PCR synthesis of IDS, FRAXA, FRAXE, and DXS1113 specific amplicons. The DNA analysis for all three patients demonstrated a complete deletion of IDS, FRAXA, and FRAXE contiguous genes. We further performed SNP-array to delineate the deletion breakpoints and to characterize the deletion extension in the different patients. The results indicated a â¼9.4 Mb deletion in Patient 1, a â¼3.9 Mb deletion of the Xq27.3-Xq28 and a â¼3.1 Mb duplication of the X q28 region in Patient 2 and a â¼41.8 Kb deletion in Patient 3. SNP-array was shown to be important to map for deletion breakpoints. A comprehensive molecular analysis in patients with Hunter syndrome, especially in the ones presenting the severe form, is important to the understanding of the genetic determinants of the phenotype and for the genetic counseling to be provided to the families.
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Mucopolissacaridose II/genética , Deleção de Sequência , Pontos de Quebra do Cromossomo , Deleção Cromossômica , Humanos , Iduronato Sulfatase/genética , Fenótipo , Polimorfismo de Nucleotídeo ÚnicoRESUMO
Cell wall biopolymers are major factors responsible for the high recalcitrance of sugarcane biomass. The study of suberization and lignification mechanisms in sugarcane and of the networks that control biosynthesis of these polymers will contribute to the biotechnological improvement of this crop. Here, we describe experiments that allow the visualization of the suberization and lignification mechanism in response to mechanical injury in sugarcane.
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Saccharum , Biomassa , Parede Celular , Grão Comestível , LigninaRESUMO
Sugarcane bagasse has received attention as a raw material for the production of second-generation ethanol (E2G). However, its use is limited because of the cell wall recalcitrance, mostly conferred by lignin. Recently our knowledge of the genes coding for the enzymes of the lignin biosynthesis pathway has increased; however, still little is known about the transcription factors controlling the expression of these genes in sugarcane. Here we describe protocols to optimize the isolation of the promoters of the lignin biosynthetic genes ShCAD8, ShCOMT and ShF5H and the transcription factors (TFs) ShMYB85 and ShMYB58/63 in Saccharum species. To confirm whether these TFs are able to activate the target promoters, a transactivation assay in BY2 protoplasts of Nicotiana tabacum is also detailed.
Assuntos
Saccharum , Celulose/metabolismo , Regulação da Expressão Gênica de Plantas , Lignina/metabolismo , Saccharum/genética , Saccharum/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
BACKGROUND: Achondroplasia (ACH), the most common form of disproportionate short stature, is caused by a pathogenic variant in the fibroblast growth factor receptor 3 gene. Recent advances in drug therapy for ACH have highlighted the importance of elucidating the natural history and socioeconomic burden of this condition. Recognition that there are many potential issues for the patient with ACH is the first step in planning cost-effective interventions in Latin America (LATAM), a vast geographic territory comprising countries with multicultural characteristics and wide socioeconomic differences. We conducted a systematic literature review to characterize the impact of ACH on affected individuals and on healthcare resources in LATAM countries. METHODS: Searches of the global medical literature as well as regional and local medical literature up to August 2020. Observational studies on patients with ACH from any LATAM country. Pairs of reviewers independently screened eligible articles, extracted data from included studies, and assessed their risk of bias. RESULTS: Fifty-three unique studies (28 case series and cross-sectional studies and 25 case reports) including data on 1604 patients were eligible. Of these studies, 11 had data available for meta-analysis. Both premature mortality and all-cause mortality in the pooled studies was 15% [95% Confidence Interval (CI) 1.0E-3 to 0.47; I2 = 82.9%, p = 0.0029; three studies, n = 99 patients]. Frequency of cardio-respiratory-metabolic disorders was 17% [95% CI 0.04-0.37; I2 = 90.3%, p < 0.0001; four studies, n = 230 patients]; nervous system disorders was 18% [95% CI 0.07-0.33; I2 = 84.6%, p < 0.0001; six studies, n = 262 patients]; ear, nose, throat and speech disorders was 32% [95% CI 0.18-0.48; I2 = 73.4%, p = 0.0046; five studies, n = 183 patients]; and spinal issues including stenosis, compression and associated pain was 24% [95% CI 0.07-0.47; I2 = 91.3%, p < 0.0001; five studies, n = 235 patients]. CONCLUSIONS: There is currently evidence of high clinical burden in ACH patients in LATAM countries. Establishing the impact of ACH provides the necessary foundation for planning tailored and effective public health interventions.