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1.
Nucleic Acids Res ; 48(12): 6672-6684, 2020 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-32504494

RESUMO

Hereditary mutations in polynucleotide kinase-phosphatase (PNKP) result in a spectrum of neurological pathologies ranging from neurodevelopmental dysfunction in microcephaly with early onset seizures (MCSZ) to neurodegeneration in ataxia oculomotor apraxia-4 (AOA4) and Charcot-Marie-Tooth disease (CMT2B2). Consistent with this, PNKP is implicated in the repair of both DNA single-strand breaks (SSBs) and DNA double-strand breaks (DSBs); lesions that can trigger neurodegeneration and neurodevelopmental dysfunction, respectively. Surprisingly, however, we did not detect a significant defect in DSB repair (DSBR) in primary fibroblasts from PNKP patients spanning the spectrum of PNKP-mutated pathologies. In contrast, the rate of SSB repair (SSBR) is markedly reduced. Moreover, we show that the restoration of SSBR in patient fibroblasts collectively requires both the DNA kinase and DNA phosphatase activities of PNKP, and the fork-head associated (FHA) domain that interacts with the SSBR protein, XRCC1. Notably, however, the two enzymatic activities of PNKP appear to affect different aspects of disease pathology, with reduced DNA phosphatase activity correlating with neurodevelopmental dysfunction and reduced DNA kinase activity correlating with neurodegeneration. In summary, these data implicate reduced rates of SSBR, not DSBR, as the source of both neurodevelopmental and neurodegenerative pathology in PNKP-mutated disease, and the extent and nature of this reduction as the primary determinant of disease severity.


Assuntos
Quebras de DNA de Cadeia Dupla , Quebras de DNA de Cadeia Simples , Enzimas Reparadoras do DNA/genética , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Proteína 1 Complementadora Cruzada de Reparo de Raio-X/genética , Apraxias/genética , Apraxias/patologia , Doença de Charcot-Marie-Tooth/genética , Doença de Charcot-Marie-Tooth/patologia , Reparo do DNA/genética , Fibroblastos/metabolismo , Fibroblastos/patologia , Humanos , Microcefalia/genética , Microcefalia/patologia , Mutação/genética , Convulsões/genética , Convulsões/patologia
2.
Sensors (Basel) ; 22(1)2021 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-35009729

RESUMO

The emergence of Industry 4.0 technologies, such as the Internet of Things (IoT) and Wireless Sensor Networks (WSN), has prompted a reconsideration of methodologies for network security as well as reducing operation and maintenance costs, especially at the physical layer, where the energy consumption plays an important role. This article demonstrates through simulations and experiments that, while the cooperative scheme is more efficient when a WSN is at normal operating conditions, the collaborative scheme offers more enhanced protection against the aggressiveness of jamming in the performance metrics, thus making it safer, reducing operation and maintenance costs and laying the foundations for jamming mitigation. This document additionally offers an algorithm to detect jamming in real time. Firstly, it examines the characteristics and damages caused by the type of aggressor. Secondly, it reflects on the natural immunity of the WSN (which depends on its node density and a cooperative or collaborative configuration). Finally, it considers the performance metrics, especially those that impact energy consumption during transmission.

3.
Neurogenetics ; 19(4): 215-225, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30039206

RESUMO

Charcot-Marie-Tooth disease (CMT) represents a heterogeneous group of hereditary peripheral neuropathies. We previously reported a CMT locus on chromosome 19q13.3 segregating with the disease in a large Costa Rican family with axonal neuropathy and autosomal recessive pattern of inheritance (CMT2B2). We proposed a homozygous missense variant in the Mediator complex 25 (MED25) gene as causative of the disease. Nevertheless, the fact that no other CMT individuals with MED25 variants were reported to date led us to reevaluate the original family. Using exome sequencing, we now identified a homozygous nonsense variant (p.Gln517ter) in the last exon of an adjacent gene, the polynucleotide kinase 3'-phosphatase (PNKP) gene. It encodes a DNA repair protein recently associated with recessive ataxia with oculomotor apraxia type 4 (AOA4) and microcephaly, seizures, and developmental delay (MCSZ). Subsequently, five unrelated Costa Rican CMT2 subjects initially identified as being heterozygous for the same MED25 variant were found to be also compound heterozygote for PNKP. All were heterozygous for the same variant found homozygous in the large family and a second one previously associated with ataxia (p.Thr408del). Detailed clinical reassessment of the initial family and the new individuals revealed in all an adult-onset slowly progressive CMT2 associated with signs of cerebellar dysfunction such as slurred speech and oculomotor involvement, but neither microcephaly, seizures, nor developmental delay. We propose that PKNP variants are the major causative variant for the CMT2 phenotype in these individuals and that the milder clinical manifestation is due to an allelic effect.


Assuntos
Doença de Charcot-Marie-Tooth/genética , Enzimas Reparadoras do DNA/genética , Complexo Mediador/genética , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Adulto , Substituição de Aminoácidos/genética , Estudos de Casos e Controles , Consanguinidade , Costa Rica , Análise Mutacional de DNA , Enzimas Reparadoras do DNA/química , Família , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Moleculares , Mutação de Sentido Incorreto , Linhagem , Fosfotransferases (Aceptor do Grupo Álcool)/química , Polimorfismo de Nucleotídeo Único
4.
Am J Hum Biol ; 30(1)2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28884857

RESUMO

OBJECTIVES: The aim of this study was to address the hypothesis that Amerindian ancestry is associated with extended longevity in the admixed population of Nicoya, Costa Rica. The Nicoya Peninsula of Costa Rica has been considered a "longevity island," particularly for males. METHODS: We estimated Amerindian ancestry using 464 ancestral informative markers in 20 old Nicoyans aged ≥99 years, and 20 younger Nicoyans (60-65 years). We used logistic regression to estimate odds ratio (OR) and 95% confidence interval (CI) of the association of Amerindian ancestry and longevity. RESULTS: Older Nicoyans had higher Amerindian ancestry compared to younger Nicoyans (43.3% vs 36.0%, P = .04). Each 10% increase of Amerindian ancestry was associated with more than twice the odds of being long-lived (OR = 2.32, 95% CI = 1.03-5.25). CONCLUSIONS AND IMPLICATIONS: To our knowledge, this is the first time that ancestry is implicated as a likely determinant of extended longevity. Amerindian-specific alleles may protect against early mortality. The identification of these protective alleles should be the focus of future studies.


Assuntos
Indígenas Centro-Americanos/estatística & dados numéricos , Longevidade , Idoso , Idoso de 80 Anos ou mais , Costa Rica , Humanos , Pessoa de Meia-Idade
5.
J Med Genet ; 53(12): 820-827, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27439707

RESUMO

BACKGROUND: Heterozygous copy number variants (CNVs) or sequence variants in the contactin-associated protein 2 gene CNTNAP2 have been discussed as risk factors for a wide spectrum of neurodevelopmental and neuropsychiatric disorders. Bi-allelic aberrations in this gene are causative for an autosomal-recessive disorder with epilepsy, severe intellectual disability (ID) and cortical dysplasia (CDFES). As the number of reported individuals is still limited, we aimed at a further characterisation of the full mutational and clinical spectrum. METHODS: Targeted sequencing, chromosomal microarray analysis or multigene panel sequencing was performed in individuals with severe ID and epilepsy. RESULTS: We identified homozygous mutations, compound heterozygous CNVs or CNVs and mutations in CNTNAP2 in eight individuals from six unrelated families. All aberrations were inherited from healthy, heterozygous parents and are predicted to be deleterious for protein function. Epilepsy occurred in all affected individuals with onset in the first 3.5 years of life. Further common aspects were ID (severe in 6/8), regression of speech development (5/8) and behavioural anomalies (7/8). Interestingly, cognitive impairment in one of two affected brothers was, in comparison, relatively mild with good speech and simple writing abilities. Cortical dysplasia that was previously reported in CDFES was not present in MRIs of six individuals and only suspected in one. CONCLUSIONS: By identifying novel homozygous or compound heterozygous, deleterious CNVs and mutations in eight individuals from six unrelated families with moderate-to-severe ID, early onset epilepsy and behavioural anomalies, we considerably broaden the mutational and clinical spectrum associated with bi-allelic aberrations in CNTNAP2.


Assuntos
Variações do Número de Cópias de DNA , Epilepsia/genética , Deficiência Intelectual/genética , Proteínas de Membrana/genética , Mutação , Proteínas do Tecido Nervoso/genética , Adolescente , Adulto , Alelos , Criança , Pré-Escolar , Anormalidades Craniofaciais , Análise Mutacional de DNA , Epilepsias Parciais/genética , Epilepsias Parciais/metabolismo , Epilepsia/diagnóstico , Feminino , Predisposição Genética para Doença , Humanos , Lactente , Deficiência Intelectual/diagnóstico , Masculino , Malformações do Desenvolvimento Cortical/genética , Malformações do Desenvolvimento Cortical/metabolismo , Pessoa de Meia-Idade , Linhagem , Fenótipo , Síndrome
6.
Rev Biol Trop ; 62(4): 1285-93, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25720167

RESUMO

The p.Thr124Met mutation in the myelin protein zero (MPZ) causes the Charcot-Marie-Tooth disease type 2J, a peripheral neuropathy with additional symptoms as pupillary alterations and deafness. It was observed in several families around the world originating e. g. from Germany, Belgium, Japan, Italy and North America. Here we report Central American patients originating from a family in Costa Rica carrying this mutation. Clinical, electrophysiological and molecular analysis of patients and controls were performed, including gene and linked markers' sequencing. Carriers share almost the entire haplotype with two non related Belgian CMT patients. As a result of the haplotype analysis, based on ten markers (seven SNPs, two microsatellites and an intronic polyA stretch), the founder effect hypothesis for this allele migration is suggestive.


Assuntos
Doença de Charcot-Marie-Tooth/genética , Perda Auditiva Neurossensorial/genética , Proteína P0 da Mielina/genética , Mutação Puntual/genética , Adulto , Idoso , Estudos de Casos e Controles , Doença de Charcot-Marie-Tooth/etnologia , Costa Rica , Feminino , Efeito Fundador , Haplótipos , Perda Auditiva Neurossensorial/etnologia , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem , Adulto Jovem
7.
Eur J Hum Genet ; 30(1): 101-110, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34697416

RESUMO

Biallelic PNKP variants cause heterogeneous disorders ranging from neurodevelopmental disorder with microcephaly/seizures to adult-onset Charcot-Marie-Tooth disease. To date, only postnatal descriptions exist. We present the first prenatal diagnosis of PNKP-related primary microcephaly. Pathological examination of a male fetus in the 18th gestational week revealed micrencephaly with extracerebral malformations and thus presumed syndromic microcephaly. A recessive disorder was suspected because of previous pregnancy termination for similar abnormalities. Prenatal trio-exome sequencing identified compound heterozygosity for the PNKP variants c.498G>A, p.[(=),0?] and c.302C>T, p.(Pro101Leu). Segregation confirmed both variants in the sister fetus. Through RNA analyses, we characterized exon 4 skipping affecting the PNKP forkhead-associated (FHA) and phosphatase domains (p.Leu67_Lys166del) as the predominant effect of the paternal c.498G>A variant. We retrospectively investigated two unrelated individuals diagnosed with biallelic PNKP-variants to compare prenatal/postnatal phenotypes. Both carry the splice donor variant c.1029+2T>C in trans with a variant in the FHA domain (c.311T>C, p.(Leu104Pro); c.151G>C, p.(Val51Leu)). RNA-seq showed complex splicing for c.1029+2T>C and c.151G>C. Structural modeling revealed significant clustering of missense variants in the FHA domain with variants generating structural damage. Our clinical description extends the PNKP-continuum to the prenatal stage. Investigating possible PNKP-variant effects using RNA and structural modeling, we highlight the mutational complexity and exemplify a PNKP-variant characterization framework.


Assuntos
Enzimas Reparadoras do DNA/genética , Microcefalia/genética , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Adulto , Enzimas Reparadoras do DNA/química , Feminino , Feto/anormalidades , Humanos , Masculino , Microcefalia/diagnóstico , Mutação de Sentido Incorreto , Fenótipo , Fosfotransferases (Aceptor do Grupo Álcool)/química , Diagnóstico Pré-Natal , Domínios Proteicos , Splicing de RNA
8.
Nutrients ; 13(8)2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34444746

RESUMO

Elderly Costa Ricans have lower mortality rates compared to their counterparts from developed countries. Reasons for this survival advantage are not completely known. In the present study, we aimed to identify dietary factors associated with leukocyte telomere length (LTL), a marker of biologic aging, in the elderly population of Costa Rica. We conducted prospective analysis in 909 participants aged 60+ years from the Costa Rican Longevity and Healthy Aging Study (CRELES). We used a food frequency questionnaire to assess usual diet. We calculated dietary patterns using Principal Component Analysis (PCA). We used generalized linear models to examine the association of dietary patterns and food groups with leukocyte telomere length. We found two major dietary patterns explaining 9.15% and 7.18% of the total variation of food intake, respectively. The first dietary pattern, which represents a traditional Costa Rican rice and beans pattern, was more frequent in rural parts of the country and was positively associated with baseline LTL: ß (95% CI) = 42.0 base-pairs (bp) (9.9 bp, 74.1 bp) per one-unit increase of the traditional dietary pattern. In analysis of individual food groups, intake of grains was positively associated with baseline LTL: ß (95% CI) = 43.6 bp (13.9 bp, 73.3 bp) per one-serving/day increase of consumption of grains. Our results suggest that dietary factors, in particular a traditional food pattern, are associated with telomere length and may contribute to the extended longevity of elderly Costa Ricans.


Assuntos
Dieta , Leucócitos , Longevidade , Telômero , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Costa Rica , Fabaceae , Feminino , Alimentos , Envelhecimento Saudável , Humanos , Masculino
9.
Cad Saude Publica ; 37(5): e00078820, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34076096

RESUMO

Historically, human migrations have determined the spread of many infectious diseases by promoting the emergence of temporal outbreaks between populations. We aimed to analyze health indicators, expenditure, and disability caused by tuberculosis (TB) and HIV/AIDS burden under the Colombian-Venezuelan migration flow focusing on the Northeastern border. A retrospective study was conducted using TB and HIV/AIDS data since 2009. We consolidated a database using official reports from the Colombian Surveillance System, World Health Organization, Indexmundi, the Global Health Observatory, IHME HIV atlas, and Joint United Nations Programme on HIV/AIDS (UNAIDS). Disability metrics regarding DALYs (disability adjusted life years) and YLDs (years lived with disability), were compared between countries. Mapping was performed on ArcGIS using official migration data of Venezuelan citizens. Our results indicate that TB profiles from Colombia and Venezuela are identical in terms of disease burden, except for an increase in TB incidence in the Colombian-Venezuelan border departments in recent years, concomitantly with the massive Venezuelan immigration since 2005. We identified a four-fold underfunding for the TB program in Venezuela, which might explain the low-testing rates for cases of multidrug-resistant TB (67%) and HIV/AIDS (60%), as well as extended hospital stays (150 days). We found a significant increase in DALYs of HIV/AIDS patients in Venezuela, specifically, 362.35 compared to 265.37 observed in Colombia during 2017. This study suggests that the Venezuelan massive migration and program underfunding might exacerbate the dual burden of TB and HIV in Colombia, especially towards the Colombian-Venezuelan border.


Assuntos
Infecções por HIV , Tuberculose , Brasil , Colômbia/epidemiologia , Emigração e Imigração , Infecções por HIV/epidemiologia , Humanos , Estudos Retrospectivos , Tuberculose/epidemiologia , Venezuela/epidemiologia
10.
Cell Immunol ; 260(2): 75-82, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-19917503

RESUMO

Duchenne muscular dystrophy (DMD) is a lethal X-linked musculodegenerative condition consisting of an underlying genetic defect whose manifestation is augmented by inflammatory mechanisms. Previous treatment approaches using gene replacement, exon-skipping or allogeneic cell therapy have been relatively unsuccessful. The only intervention to mediate improvement in survival, albeit minor, is glucocorticoid treatment. Given this modality appears to function via suppression of underlying inflammation; we focus this review on the inflammatory response as a target for mesenchymal stem cell (MSC) therapy. In contrast to other cell based therapies attempted in DMD, MSC have the advantages of (a) ability to fuse with and genetically complement dystrophic muscle; (b) possess anti-inflammatory activities; and (c) produce trophic factors that may augment activity of endogenous repair cells. We conclude by describing one practical scenario of stem cell therapy for DMD.


Assuntos
Inflamação/imunologia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/imunologia , Distrofia Muscular de Duchenne/cirurgia , Animais , Diferenciação Celular , Humanos , Células-Tronco Mesenquimais/citologia , Músculo Esquelético/imunologia , Músculo Esquelético/patologia , Distrofia Muscular de Duchenne/imunologia , Resultado do Tratamento
11.
PLoS One ; 15(12): e0237682, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33332469

RESUMO

The molecular function of a protein relies on its structure. Understanding how variants alter structure and function in multidomain proteins is key to elucidate the generation of a pathological phenotype. However, one may fall into the logical bias of assessing protein damage only based on the variants that are visible (survivorship bias), which can lead to partial conclusions. This is the case of PNKP, an important nuclear and mitochondrial DNA repair enzyme with both kinase and phosphatase function. Most variants in PNKP are confined to the kinase domain, leading to a pathological spectrum of three apparently distinct clinical entities. Since proteins and domains may have a different tolerability to variation, we evaluated whether variants in PNKP are under survivorship bias. Here, we provide the evidence that supports a higher tolerance in the kinase domain even when all variants reported are deleterious. Instead, the phosphatase domain is less tolerant due to its lower variant rates, a higher degree of sequence conservation, lower dN/dS ratios, and the presence of more disease-propensity hotspots. Together, our results support previous experimental evidence that demonstrated that the phosphatase domain is functionally more necessary and relevant for DNA repair, especially in the context of the development of the central nervous system. Finally, we propose the term "Wald's domain" for future studies analyzing the possible survivorship bias in multidomain proteins.


Assuntos
Enzimas Reparadoras do DNA/genética , Mutação/genética , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Sequência de Aminoácidos , Núcleo Celular/genética , Dano ao DNA/genética , Reparo do DNA/genética , Proteínas de Ligação a DNA/genética , Humanos , Mitocôndrias/genética , Monoéster Fosfórico Hidrolases/genética , Sobrevivência
12.
Neurogenetics ; 10(4): 275-87, 2009 10.
Artigo em Inglês | MEDLINE | ID: mdl-19290556

RESUMO

Charcot-Marie-Tooth (CMT) disease is a clinically and genetically heterogeneous disorder. All mendelian patterns of inheritance have been described. We identified a homozygous p.A335V mutation in the MED25 gene in an extended Costa Rican family with autosomal recessively inherited Charcot-Marie-Tooth neuropathy linked to the CMT2B2 locus in chromosome 19q13.3. MED25, also known as ARC92 and ACID1, is a subunit of the human activator-recruited cofactor (ARC), a family of large transcriptional coactivator complexes related to the yeast Mediator. MED25 was identified by virtue of functional association with the activator domains of multiple cellular and viral transcriptional activators. Its exact physiological function in transcriptional regulation remains obscure. The CMT2B2-associated missense amino acid substitution p.A335V is located in a proline-rich region with high affinity for SH3 domains of the Abelson type. The mutation causes a decrease in binding specificity leading to the recognition of a broader range of SH3 domain proteins. Furthermore, Med25 is coordinately expressed with Pmp22 gene dosage and expression in transgenic mice and rats. These results suggest a potential role of this protein in the molecular etiology of CMT2B2 and suggest a potential, more general role of MED25 in gene dosage sensitive peripheral neuropathy pathogenesis.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Substituição de Aminoácidos , Proteínas de Ciclo Celular , Doença de Charcot-Marie-Tooth/genética , Complexo Mediador , Proteínas da Mielina , Proteínas Nucleares , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adulto , Sequência de Aminoácidos , Animais , Animais Geneticamente Modificados , Sequência de Bases , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Doença de Charcot-Marie-Tooth/fisiopatologia , Costa Rica , Análise Mutacional de DNA , Modelos Animais de Doenças , Feminino , Dosagem de Genes , Genótipo , Humanos , Masculino , Complexo Mediador/química , Complexo Mediador/genética , Complexo Mediador/metabolismo , Camundongos , Modelos Moleculares , Dados de Sequência Molecular , Proteínas da Mielina/genética , Proteínas da Mielina/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Linhagem , Conformação Proteica , Ratos
13.
Neurol Res ; 31(3): 283-8, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18826755

RESUMO

OBJECTIVE: To describe the clinical, electrophysiologic and morphologic features of a Costa Rican family with an autosomal dominant inherited Charcot-Marie-Tooth (CMT) neuropathy. METHODS: The field study took place in Costa Rica, Central America. Seven patients underwent neurological examinations and standard electrodiagnostic tests, and a sural nerve biopsy was taken from one patient. Fifteen family members were screened for gene defects associated with CMT disease. RESULTS: Characteristic features of this family were a late age of onset (35-56 years), positive sensory symptoms and muscle cramps. Based on electrodiagnostic and morphologic data, the patients were classified as having a CMT2 neuropathy. The CMT1A duplication/HNPP deletion and point mutations in genes PMP22, MPZ, Cx32 and EGR2 implicated in the most common types of CMT disease were excluded. Subsequently, almost all known CMT loci were excluded by linkage analysis. DISCUSSION: Features of this family were a late age of onset and positive sensory symptoms. This new autosomal dominant CMT neuropathy is associated with an unknown gene defect.


Assuntos
Doença de Charcot-Marie-Tooth/diagnóstico , Doença de Charcot-Marie-Tooth/genética , Saúde da Família , Adulto , Idade de Início , Idoso , Doença de Charcot-Marie-Tooth/patologia , Doença de Charcot-Marie-Tooth/fisiopatologia , Costa Rica , Feminino , Genes Dominantes , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem
14.
Transl Neurodegener ; 8: 14, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31110700

RESUMO

Mutations in DNA repair enzymes can cause two neurological clinical manifestations: a developmental impairment and a degenerative disease. Polynucleotide kinase 3'-phosphatase (PNKP) is an enzyme that is actively involved in DNA repair in both single and double strand break repair systems. Mutations in this protein or others in the same pathway are responsible for a complex group of diseases with a broad clinical spectrum. Besides, mitochondrial dysfunction also has been consolidated as a hallmark of brain degeneration. Here we provide evidence that supports a shared role between mitochondrial dysfunction and DNA repair defects in the pathogenesis of the nervous system. As models, we analyze PNKP-related disorders, focusing on Charcot-Marie-Tooth disease and ataxia. A better understanding of the molecular dynamics of this relationship could provide improved diagnosis and treatment for neurological diseases.

15.
PLoS One ; 14(10): e0223766, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31603943

RESUMO

The objective is to identify cofactors of leukocyte telomere length (LTL) in a Latin American population, specifically the association of LTL with 36 socio-demographic, early childhood, and health characteristics, as well as with DNA sample collection and storage procedures. The analysis is based on longitudinal information from a subsample of 1,261 individuals aged 60+ years at baseline from the Costa Rican Study of Longevity and Healthy Aging (CRELES): a nationally representative sample of elderly population. Random effects regression models for panel data were used to estimate the associations with LTL and its longitudinal changes. Sample collection procedures and DNA refrigerator storage time were strongly associated with LTL: telomeres are longer in blood collected in October-December, in DNA extracted from <1-year-old blood cells, and in DNA stored at 4°C for longer periods of time up to five years. The data confirmed that telomeres are shorter at older ages, as well as among males, and diabetic individuals, whereas telomeres are longer in the high-longevity Nicoya region. Most health, biomarkers, and early childhood indicators did not show significant associations with LTL. Longitudinal LTL variation over approximately two years was mainly associated with baseline LTL levels, as found in other studies. Our findings suggest that if there is unavoidable variability in season of sample collection and DNA storage time, these factors should be controlled for in all demographic and epidemiologic studies of LTL. However, due to unobserved components of measurement variation, statistical control may be inadequate as compared to standardization of data collection procedures.


Assuntos
Coleta de Amostras Sanguíneas/métodos , DNA/normas , Leucócitos/química , Longevidade , Telômero/genética , Idoso , Costa Rica , Feminino , Envelhecimento Saudável , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Homeostase do Telômero , Fatores de Tempo
16.
Cell Immunol ; 253(1-2): 11-5, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18627903

RESUMO

Mesenchymal stem cell (MSC) therapy is the most clinically advanced form of cell therapy, second to hematopoietic stem cell transplants. To date, MSC have been used for immune modulation in conditions such as Graft Versus Host Disease (GVHD) and Crohn's Disease, for which Phase III clinical trials are currently in progress. Here, we review the immunological properties of MSC and make a case for their use in treatment of Charcot-Marie-Tooth disease type 1 (CMT1), a group of inherited peripheral neuropathies. CMT1 is characterized by demyelination and aberrant immune activation making this condition an ideal target for exploration of MSC therapy, given the ability of these cells to promote sheath regeneration as well as suppress inflammation. Studies supporting this hypothesis will be presented and placed into the context of other cell-based approaches that are theoretically feasible. Given that MSCs selectively home to areas of inflammation, as well as exert effects in an allogeneic manner, the possibility of an "off the shelf" therapy for CMT1 will be discussed.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos/métodos , Doença de Charcot-Marie-Tooth , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/imunologia , Animais , Doença de Charcot-Marie-Tooth/imunologia , Doença de Charcot-Marie-Tooth/terapia , Modelos Animais de Doenças , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/terapia , Humanos , Imunidade Inata/fisiologia , Células-Tronco Mesenquimais/citologia
17.
Cancer Res ; 65(4): 1414-24, 2005 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-15735029

RESUMO

The growth and metastasis of tumors are heavily dependent on angiogenesis, but much of the transcriptional regulation of vascular endothelial cell gene expression responsible for angiogenesis remains to be elucidated. The homeobox gene Gax is expressed in vascular endothelial cells and inhibits proliferation and tube formation in vitro. We hypothesized that Gax is a negative transcriptional regulator of the endothelial cell angiogenic phenotype and studied its regulation and activity in vascular endothelial cells. Several proangiogenic factors caused a rapid down-regulation of Gax mRNA in human vascular endothelial cells, as did conditioned media from breast cancer cell lines. In addition, Gax expression using a replication-deficient adenoviral vector inhibited human umbilical vein endothelial cell migration toward proangiogenic factors in vitro and inhibited angiogenesis in vivo in Matrigel plugs. To identify putative downstream targets of Gax, we examined changes in global gene expression in endothelial cells due to Gax activity. Gax expression resulted in changes in global gene expression consistent with a quiescent, nonangiogenic phenotype, with increased expression of cyclin kinase inhibitors and decreased expression of genes implicated in endothelial cell activation and angiogenesis. Further analysis revealed that Gax down-regulated numerous nuclear factor-kappaB (NF-kappaB) target genes and decreased the binding of NF-kappaB to its target sequence in electrophoretic mobility shift assays. To our knowledge, Gax is the first homeobox gene described that inhibits NF-kappaB activity in vascular endothelial cells. Because NF-kappaB has been implicated in endothelial cell activation and angiogenesis, the down-regulation of NF-kappaB-dependent genes by Gax suggests one potential mechanism by which Gax inhibits the angiogenic phenotype.


Assuntos
Regulação para Baixo/fisiologia , Endotélio Vascular/fisiologia , Proteínas de Homeodomínio/genética , NF-kappa B/antagonistas & inibidores , Neovascularização Fisiológica/genética , Animais , Movimento Celular/fisiologia , Sequência Consenso , DNA/genética , DNA/metabolismo , Regulação para Baixo/efeitos dos fármacos , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Perfilação da Expressão Gênica , Proteínas de Homeodomínio/biossíntese , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Mitógenos/farmacologia , NF-kappa B/genética , NF-kappa B/metabolismo
18.
JIMD Rep ; 36: 59-66, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28130718

RESUMO

Intellectual disability is a highly heterogeneous disease that affects the central nervous system and impairs patients' ability to function independently. Despite multiples genes involved in the etiology of disease, most of the genetic background is yet to be discovered. We used runs of homozygosity and exome sequencing to study a large Costa Rican family with four individuals affected with severe intellectual disability and found a novel homozygous missense mutation, p. 96G>R, c. 286G>A, in all affected individuals. This gene encodes for a pyridoxal enzyme involved in the production of the neurotransmitter glutamate and is highly expressed in the white matter of brain and cerebellum. Protein modeling of GPT2 predicted that the mutation is located in a loop where the substrate binds to the active site of the enzyme, therefore, suggesting that the catalytic activity is impaired. With our report of a second mutation we fortify the importance of GPT2 as a novel cause of autosomal recessive nonsyndromic intellectual disability and support the premise that GPT2 is highly important for the neurodevelopment of the central nervous system. SYNOPSIS: The mutation p. 96G>R c. 286G>A in GPT2, located in a loop where the substrate binds to the active site of the enzyme, fortifies the importance of GPT2 in the pathogenesis of nonsyndromic intellectual disability.

19.
Annu Int Conf IEEE Eng Med Biol Soc ; 2017: 3032-3035, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29060537

RESUMO

One of the key issues about wireless technologies is their interaction with the human body. The so-called internet of things will comprise many devices that will transmit either around or through the human body. These devices must be tested either in their working medium, when possible, or in the most realistic one. For this purpose, tissue-like phantoms are the best alternative to carry out realistic analyses of the performance of body area networks. In addition, they are the conventional way to certify the compliance of commercial standards by these devices. However, the number of phantoms that work in large bandwidths is limited in literature. This work aims at presenting chemical solutions that will be useful to prepare a variety of wideband tissue phantoms. Besides, the colon was mimicked in two ways, the healthy tissue and the malignant one, taking into account studies that relate changes on the relative permittivity with cancer. They were designed on the basis of acetonitrile in aqueous solutions as described in a previous work. Thus, many scenarios could be developed such as multilayers which imitate parts of the heterogeneous body.


Assuntos
Imagens de Fantasmas , Humanos , Internet , Tecnologia sem Fio
20.
Cad. Saúde Pública (Online) ; 37(5): e00078820, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1249447

RESUMO

Abstract: Historically, human migrations have determined the spread of many infectious diseases by promoting the emergence of temporal outbreaks between populations. We aimed to analyze health indicators, expenditure, and disability caused by tuberculosis (TB) and HIV/AIDS burden under the Colombian-Venezuelan migration flow focusing on the Northeastern border. A retrospective study was conducted using TB and HIV/AIDS data since 2009. We consolidated a database using official reports from the Colombian Surveillance System, World Health Organization, Indexmundi, the Global Health Observatory, IHME HIV atlas, and Joint United Nations Programme on HIV/AIDS (UNAIDS). Disability metrics regarding DALYs (disability adjusted life years) and YLDs (years lived with disability), were compared between countries. Mapping was performed on ArcGIS using official migration data of Venezuelan citizens. Our results indicate that TB profiles from Colombia and Venezuela are identical in terms of disease burden, except for an increase in TB incidence in the Colombian-Venezuelan border departments in recent years, concomitantly with the massive Venezuelan immigration since 2005. We identified a four-fold underfunding for the TB program in Venezuela, which might explain the low-testing rates for cases of multidrug-resistant TB (67%) and HIV/AIDS (60%), as well as extended hospital stays (150 days). We found a significant increase in DALYs of HIV/AIDS patients in Venezuela, specifically, 362.35 compared to 265.37 observed in Colombia during 2017. This study suggests that the Venezuelan massive migration and program underfunding might exacerbate the dual burden of TB and HIV in Colombia, especially towards the Colombian‐Venezuelan border.


Resumen: Históricamente, las migraciones humanas han determinado la expansión de muchas enfermedades infecciosas, promoviendo el surgimiento de brotes temporales en la población. Nuestro objetivo fue analizar indicadores de salud, gastos, así como la discapacidad causada por la tuberculosis (TB) y la carga del VIH/SIDA ante el flujo migratorio entre Colombia-Venezuela, centrándose en los departamentos fronterizos del nordeste. Se realizó un estudio retrospectivo usando datos sobre TB y VIH/SIDA desde 2009. Consolidamos una base de datos usando informes oficiales del Sistema de Vigilancia Colombiano, Organización Mundial de la Salud, Indexmundi, Observatorio Global de la Salud, IHME HIV atlas, y Programa Conjunto de las Naciones Unidas sobre el VIH/SIDA (ONUSIDA). Se midió la discapacidad en términos del DALYs (incapacidad ajustada por años de vida) y YLDs (años vividos con discapacidad) y se compararon entre ambos países. El mapeo se realizó en ArcGIS, usando datos oficiales de migración de ciudadanos venezolanos. Nuestros resultados indican que los perfiles de TB de Colombia y Venezuela son idénticos, en lo que se refiere a la carga de la enfermedad, excepto por el incremento en la incidencia de TB en los departamentos fronterizos de la frontera entre Colombia y Venezuela en años recientes, concomitantemente con la inmigración masiva venezolana desde 2005. Identificamos una cuadruplicación de la subfinanciación para el programa de TB en Venezuela, que podría explicar las bajas tasas de test para los casos multirresistentes a medicamentos contra la TB (67%) y VIH/SIDA (60%), al igual que las estancias prolongadas en el hospital (150 días). Hallamos un incremento significativo en DALYs de pacientes con VIH/SIDA en Venezuela, específicamente, 362,35 comparados con los 265,37 observados en Colombia durante 2017. Este estudio sugiere que la migración venezolana masiva y la subfinanciación del programa podrían haber exacerbado la doble carga de la TB y el VIH en Colombia, especialmente a través de la frontera entre Colombia y Venezuela.


Resumo: Historicamente, as migrações humanas determinaram a propagação de muitas doenças infecciosas ao facilitar surtos temporais entre populações. O estudo buscou analisar os indicadores sanitários e os gastos e taxas de incapacidade relacionados à tuberculose (TB) e à carga de HIV/aids no fluxo migratório entre Colômbia e Venezuela, com destaque para os departamentos (estados) da fronteira nordeste. Foi realizado um estudo retrospectivo de dados sobre TB e HIV/aids desde 2009. Consolidamos uma base de dados a partir de relatórios do Sistema de Vigilância da Colômbia, Organização Mundial da Saúde, Indexmundi, Observatório de Saúde Global, IHME HIV Atlas e Programa Conjunto das Nações Unidas sobre HIV/AIDS (UNAIDS). As métricas de incapacidade em termos de AVAIs (anos de vida ajustados para incapacidade) e AVIs (anos vividos com incapacidade) foram comparadas entre os dois países. O mapeamento foi realizado no ArcGIS, com dados oficiais sobre migração de cidadãos venezuelanos. Nossos resultados indicam que os perfis de TB da Colômbia e da Venezuela são idênticos em termos de carga de doença, exceto por um aumento da incidência de TB nos departamentos na fronteira entre os dois países em anos recentes, concomitantemente com a imigração venezuelana maciça desde 2005. Identificamos um subfinanciamento (por um fator de quatro) no programa de tuberculose da Venezuela, o que pode explicar as baixas taxas de testagem para casos de TB multirresistente (67%) e HIV/aids (60%), além das internações hospitalares prolongadas (150 dias). Encontramos um aumento significativo de AVAIs em pacientes de HIV/aids na Venezuela, especificamente 362,35 comparado com 265,37 na Colômbia em 2017. O estudo sugere que a migração maciça venezuelana e o subfinanciamento podem exacerbar a carga dupla de TB e HIV na Colômbia, principalmente na fronteira com a Venezuela.


Assuntos
Humanos , Tuberculose/epidemiologia , Infecções por HIV/epidemiologia , Venezuela/epidemiologia , Brasil , Estudos Retrospectivos , Colômbia/epidemiologia , Emigração e Imigração
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