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1.
J Med Ultrasound ; 32(3): 255-258, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39310862

RESUMO

Megacystis-microcolon-intestinal hypoperistalsis syndrome is a rare congenital disease with a poor prognosis and life expectancy. We present the prenatal diagnosis of four consecutive cases in the same woman. After medical genetics consultation, the couple was advised to resort to medically assisted reproduction techniques with oocyte donation. This case report demonstrates the recurrence of a rare disease in four consecutive pregnancies and how prenatal diagnosis assumed a preponderant role in parental counseling.

2.
Clin Genet ; 93(3): 577-587, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28940419

RESUMO

Epilepsies are common neurological disorders and genetic factors contribute to their pathogenesis. Copy number variations (CNVs) are increasingly recognized as an important etiology of many human diseases including epilepsy. Whole-exome sequencing (WES) is becoming a standard tool for detecting pathogenic mutations and has recently been applied to detecting CNVs. Here, we analyzed 294 families with epilepsy using WES, and focused on 168 families with no causative single nucleotide variants in known epilepsy-associated genes to further validate CNVs using 2 different CNV detection tools using WES data. We confirmed 18 pathogenic CNVs, and 2 deletions and 2 duplications at chr15q11.2 of clinically unknown significance. Of note, we were able to identify small CNVs less than 10 kb in size, which might be difficult to detect by conventional microarray. We revealed 2 cases with pathogenic CNVs that one of the 2 CNV detection tools failed to find, suggesting that using different CNV tools is recommended to increase diagnostic yield. Considering a relatively high discovery rate of CNVs (18 out of 168 families, 10.7%) and successful detection of CNV with <10 kb in size, CNV detection by WES may be able to surrogate, or at least complement, conventional microarray analysis.


Assuntos
Variações do Número de Cópias de DNA , Epilepsia/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Testes Genéticos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Criança , Pré-Escolar , Hibridização Genômica Comparativa , Biologia Computacional/métodos , Epilepsia/diagnóstico , Exoma , Feminino , Estudos de Associação Genética/métodos , Testes Genéticos/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Sequenciamento do Exoma , Adulto Jovem
3.
Clin Genet ; 91(2): 302-312, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-26970254

RESUMO

Perrault syndrome is a rare autosomal recessive disorder characterized by sensorineural hearing loss (SNHL) in both sexes and primary ovarian insufficiency in 46, XX karyotype females. Biallelic variants in five genes are reported to be causative: HSD17B4, HARS2, LARS2, CLPP and C10orf2. Here we present eight families affected by Perrault syndrome. In five families we identified novel or previously reported variants in HSD17B4, LARS2, CLPP and C10orf2. The proband from each family was whole exome sequenced and variants confirmed by Sanger sequencing. A female was compound heterozygous for a known, p.(Gly16Ser) and novel, p.(Val82Phe) variant in D-bifunctional protein (HSD17B4). A family was homozygous for mitochondrial leucyl aminocyl tRNA synthetase (mtLeuRS) (LARS2) p.(Thr522Asn), previously associated with Perrault syndrome. A further family was compound heterozygous for mtLeuRS, p.(Thr522Asn) and a novel variant, p.(Met117Ile). Affected individuals with LARS2 variants had low frequency SNHL, a feature previously described in Perrault syndrome. A female with significant neurological disability was compound heterozygous for p.(Arg323Gln) and p.(Asn399Ser) variants in Twinkle (C10orf2). A male was homozygous for a novel variant in CLPP, p.(Cys144Arg). In three families there were no putative pathogenic variants in these genes confirming additional disease-causing genes remain unidentified. We have expanded the spectrum of disease-causing variants associated with Perrault syndrome.


Assuntos
Aminoacil-tRNA Sintetases/genética , DNA Helicases/genética , Endopeptidase Clp/genética , Disgenesia Gonadal 46 XX/genética , Perda Auditiva Neurossensorial/genética , Proteínas Mitocondriais/genética , Proteína Multifuncional do Peroxissomo-2/genética , Exoma/genética , Feminino , Genótipo , Disgenesia Gonadal 46 XX/patologia , Perda Auditiva Neurossensorial/patologia , Homozigoto , Humanos , Masculino , Mutação , Linhagem , Fenótipo , Insuficiência Ovariana Primária/genética , Insuficiência Ovariana Primária/fisiopatologia
4.
Acta Neurol Scand ; 136(5): 541-545, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28229454

RESUMO

Spinocerebellar ataxia type 8 (SCA8) is a progressive neurological disorder caused by the expanded repeat CTA/CTG of two overlapping genes, ATXN8OS and ATXN8, expressed bidirectionally. Normal alleles have 15-50 repeats, and pathogenic alleles range from 71 to 1300 repeats. The disorder is relatively rare, accounting for about 2%-5% of the autosomal dominant forms of hereditary ataxia worldwide. However, the prevalence of disease-causing ATXN8OS/ATXN8 expansions is higher than the disease because of the reduced penetrance of the expanded allele. The aim of this study was to describe the first fully penetrant SCA8 family showing mixed Brazilian African and Amerindian origin. Eight members of this family were evaluated-the mother and seven offspring-through a complete neurological examination conducted at the Neurogenetics Clinic, HCFMRP-USP in Brazil. The number of CTA/CTG repeats was obtained after polymerase chain reaction (PCR) and fragment analysis. The haplotype analysis was conducted using a microsatellite marker, D13S1296, and four single nucleotide polymorphisms (SNPs), rs1831189, rs8002227, rs11841483, and rs72284461, all spanning a 70.1 Mb region on chromosome 13q21.3. The molecular analysis showed that the expansions ranged from 104 to 109 CTA/CTG repeats in the six affected individuals and were absent in two asymptomatic daughters (aged 53 and 40 years). Three SNPs cosegregate with the expanded alleles, confirming the connection between expansion and disease in this family. As the SCA8 diagnosis demands careful interpretation, we suggest the use of linkage analysis to observe segregation of the mutation, making more accurate its genotyping.


Assuntos
Proteínas do Tecido Nervoso/genética , Penetrância , Polimorfismo de Nucleotídeo Único , Ataxias Espinocerebelares/genética , Adulto , Idoso , Brasil , Feminino , Haplótipos , Humanos , Masculino , Pessoa de Meia-Idade , Ataxias Espinocerebelares/patologia , Expansão das Repetições de Trinucleotídeos
5.
J Med Genet ; 52(8): 514-22, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26092869

RESUMO

BACKGROUND: Joubert syndrome (JS) is a recessive neurodevelopmental disorder characterised by hypotonia, ataxia, cognitive impairment, abnormal eye movements, respiratory control disturbances and a distinctive mid-hindbrain malformation. JS demonstrates substantial phenotypic variability and genetic heterogeneity. This study provides a comprehensive view of the current genetic basis, phenotypic range and gene-phenotype associations in JS. METHODS: We sequenced 27 JS-associated genes in 440 affected individuals (375 families) from a cohort of 532 individuals (440 families) with JS, using molecular inversion probe-based targeted capture and next-generation sequencing. Variant pathogenicity was defined using the Combined Annotation Dependent Depletion algorithm with an optimised score cut-off. RESULTS: We identified presumed causal variants in 62% of pedigrees, including the first B9D2 mutations associated with JS. 253 different mutations in 23 genes highlight the extreme genetic heterogeneity of JS. Phenotypic analysis revealed that only 34% of individuals have a 'pure JS' phenotype. Retinal disease is present in 30% of individuals, renal disease in 25%, coloboma in 17%, polydactyly in 15%, liver fibrosis in 14% and encephalocele in 8%. Loss of CEP290 function is associated with retinal dystrophy, while loss of TMEM67 function is associated with liver fibrosis and coloboma, but we observe no clear-cut distinction between JS subtypes. CONCLUSIONS: This work illustrates how combining advanced sequencing techniques with phenotypic data addresses extreme genetic heterogeneity to provide diagnostic and carrier testing, guide medical monitoring for progressive complications, facilitate interpretation of genome-wide sequencing results in individuals with a variety of phenotypes and enable gene-specific treatments in the future.


Assuntos
Cerebelo/anormalidades , Heterogeneidade Genética , Retina/anormalidades , Anormalidades Múltiplas/genética , Anormalidades Múltiplas/patologia , Cerebelo/patologia , Estudos de Coortes , Análise Mutacional de DNA , Anormalidades do Olho/genética , Anormalidades do Olho/patologia , Estudos de Associação Genética , Humanos , Doenças Renais Císticas/genética , Doenças Renais Císticas/patologia , Modelos Teóricos , Linhagem , Retina/patologia , Análise de Sequência de DNA
6.
Int J Cosmet Sci ; 38(5): 535-40, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26833020

RESUMO

BACKGROUND: Bromelain is a mixture of proteolytic enzymes found in various tissues of the pineapple plant (Ananas comosus) and other species of Bromeliaceae. Owing to its proteolytic activity, bromelain has been used in the food, medical, pharmaceutical and cosmetic industries, for its cell renewal, anti-ageing, whitening and anti-cellulite properties. OBJECTIVE: This study evaluated the stability of bromelain (commercial powder) incorporated in topical formulations. METHODS: Bromelain was incorporated at three concentrations, 0.5%, 1.0% and 2.0%, in oil-in-water emulsion and gel, and stored for six months at varying stress conditions. Stability was accessed by measuring the changes in the protein content, enzymatic activity, viscosity, rheology, pH and colour of the selected formulations. RESULTS: The colour of all the samples changed after 180 days of incubation, indicating the concentration-dependence and temperature-sensitive nature of these formulations. No relationship was observed between the changes in the pH, temperature and luminosity exposure in all the samples. Gels proved to be the least preferred base for incorporation of bromelain for use as a topical formulation, owing to its inability to maintain the integrity of bromelain, thereby affecting the formulation characteristics. CONCLUSION: The emulsion-based formulations at all the concentrations of bromelain were more stable than the gel-based formulation over 180 days of evaluation, at a temperature of 5°C, protected from light.


Assuntos
Bromelaínas/química , Administração Tópica , Bromelaínas/metabolismo , Cor , Cosméticos , Reologia , Temperatura , Viscosidade
7.
J Appl Microbiol ; 119(3): 677-87, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26086953

RESUMO

AIMS: Red propolis is a resinous product popularly consumed in Brazil as it improves health, and it is considered a nutraceutical. The objective of this study was to test the antimicrobial activity of eight samples of red propolis from Brazil and Cuba to assess the possibility of application of this natural product as an antimicrobial agent, along with a study of its cytotoxic activity against non-tumor cell lines to evaluate at which concentrations it could be safely used. METHODS AND RESULTS: The chemical profile of the samples was evaluated by UHPLC-MS. All the samples presented antimicrobial activity which was tested using agar diffusion and serial dilution methods; and these samples displayed a better activity against most Gram-negative bacteria with minimum inhibitory concentration (MIC) in the range between 6·25 µg ml(-1) and 500 µg ml(-1). However our studies also revealed an inherent cytotoxic effect against HaCaT human keratinocytes and BALBc 3T3. CONCLUSIONS: To have a noncytotoxic and safe use of red propolis, it is necessary to use a concentration below the IC50 cytotoxic values. SIGNIFICANCE AND IMPACT OF THE STUDY: The traditional use of propolis does not necessarily guarantee its safety. The evaluation of the safety of bioactive natural products should always be considered together with the evaluation of the activity.


Assuntos
Antibacterianos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Própole/farmacologia , Própole/toxicidade , Animais , Antibacterianos/química , Antibacterianos/toxicidade , Células 3T3 BALB , Brasil , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Qualidade de Produtos para o Consumidor , Bactérias Gram-Negativas/crescimento & desenvolvimento , Humanos , Camundongos , Testes de Sensibilidade Microbiana , Própole/química
8.
BMC Vet Res ; 10: 194, 2014 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-25193623

RESUMO

BACKGROUND: Acute postsurgical pain is of great interest due to potential risk of becoming chronic if not treated properly, worsening patient's recovery and quality of life. Twenty-eight dogs with ruptured cruciate ligaments were divided into three groups that received intramuscular injections of 4 mg/kg of tramadol (TRA), 0.5 mg/kg of methadone (MET0.5), or 0.7 mg/kg of methadone (MET0.7). Physiological parameters (heart and respiratory rates and blood pressure) were evaluated at specified times: baseline (TBL), 1 (T1), 2 (T2), 4 (T4), 6 (T6), and 24 (T24) hours after premedication. Pain scores were described by visual analogue scale (VAS), modified Glasgow Composite, and Colorado University Acute Pain scales. Blood samples for measurement of interleukin (IL)-6 were collected at TBL, T1, T6, and T24. This was a prospective, randomised investigation to evaluate the efficacy of tramadol and methadone as premedications in dogs undergoing osteotomies. RESULTS: There were no statistically significant differences between groups with respect to age, weight, gender, surgery time, and time to extubation. Heart rate, respiratory rate, and blood pressure values were maintained within acceptable ranges, and a reduction was observed at T2 in MET0.5 and MET0.7 compared with TBL. Increases in VAS scores were observed in TRA at T4 compared with TBL, T1, and T24 and between T1 and T6 (p < 0.001). In MET0.5, there was significant increase in VAS score at T4 compared with T1 (p < 0.001). TRA and MET0.5 showed significantly higher mean ± SD VAS scores (3.4 ± 2.5 and 2.5 ± 2.6, respectively) than MET0.7 (1.1 ± 1.5) at T4 (p < 0.001). TRA showed greater demand of rescue analgesia (four animals in T4 and two in T6) (p < 0.037). There were no statistically significant differences in sedation scores, Colorado Scale scores, or interleukin levels between groups and time points. CONCLUSIONS: Methadone given as premedication in doses of 0.7 mg/kg was better at controlling pain compared with lower doses and tramadol. However, dosage increases, administered as rescue analgesia, promoted adequate pain control even in tramadol group. Influence of these analgesics on IL-6 release could not be demonstrated, but significant levels were not found.


Assuntos
Analgésicos Opioides/farmacologia , Cães/cirurgia , Interleucina-6/metabolismo , Metadona/farmacologia , Dor Pós-Operatória/veterinária , Tramadol/farmacologia , Analgésicos Opioides/administração & dosagem , Animais , Ligamento Cruzado Anterior/cirurgia , Lesões do Ligamento Cruzado Anterior , Cães/lesões , Regulação da Expressão Gênica/efeitos dos fármacos , Metadona/administração & dosagem , Medição da Dor/veterinária , Dor Pós-Operatória/prevenção & controle , Ruptura/cirurgia , Tramadol/administração & dosagem
9.
Mol Metab ; 87: 101990, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39009220

RESUMO

OBJECTIVES: This study aimed to evaluate the efficacy of a purification method developed for isolating alpha, beta, and delta cells from pancreatic islets of adult mice, extending its application to islets from newborn and aged mice. Furthermore, it sought to examine transcriptome dynamics in mouse pancreatic endocrine islet cells throughout postnatal development and to validate age-related alterations within these cell populations. METHODS: We leveraged the high surface expression of CD71 on beta cells and CD24 on delta cells to FACS-purify alpha, beta, and delta cells from newborn (1-week-old), adult (12-week-old), and old (18-month-old) mice. Bulk RNA sequencing was conducted on these purified cell populations, and subsequent bioinformatic analyses included differential gene expression, overrepresentation, and intersection analysis. RESULTS: Alpha, beta, and delta cells from newborn and aged mice were successfully FACS-purified using the same method employed for adult mice. Our analysis of the age-related transcriptional changes in alpha, beta, and delta cell populations revealed a decrease in cell cycling and an increase in neuron-like features processes during the transition from newborn to adult mice. Progressing from adult to old mice, we identified an inflammatory gene signature related to aging (inflammaging) encompassing an increase in ß-2 microglobulin and major histocompatibility complex (MHC) Class I expression. CONCLUSIONS: Our study demonstrates the effectiveness of our cell sorting technique in purifying endocrine subsets from mouse islets at different ages. We provide a valuable resource for better understanding endocrine pancreas aging and identified an inflammaging gene signature with increased ß-2 microglobulin and MHC Class I expression as a common hallmark of old alpha, beta, and delta cells, with potential implications for immune response regulation and age-related diabetes.


Assuntos
Senescência Celular , Células Secretoras de Glucagon , Células Secretoras de Insulina , Transcriptoma , Animais , Camundongos , Células Secretoras de Insulina/metabolismo , Senescência Celular/genética , Células Secretoras de Glucagon/metabolismo , Camundongos Endogâmicos C57BL , Regulação para Cima , Células Secretoras de Somatostatina/metabolismo , Masculino , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/metabolismo , Envelhecimento/genética , Envelhecimento/metabolismo , Ilhotas Pancreáticas/metabolismo , Animais Recém-Nascidos , Antígenos CD/metabolismo , Antígenos CD/genética
10.
Trans R Soc Trop Med Hyg ; 117(4): 313-315, 2023 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-36482768

RESUMO

BACKGROUND: Lack of access to diagnostic testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection can limit disease surveillance in remote areas. Serological surveillance can indicate the true extent and distribution of infections in such settings. METHODS: This study monitored SARS-CoV-2 seroprevalence in residual serum samples salvaged from laboratories at five healthcare facilities across Timor-Leste from March to October 2021. RESULTS: Seroprevalence increased from 8.3% to 87.0% during the study period. Potential immunity gaps were identified among children aged 0-15 y (who had not been eligible for vaccination) and individuals aged >60 y. CONCLUSIONS: Efforts to vaccinate vulnerable individuals including older people should be maintained. Residual serum samples can be analysed to give local, contemporary information about the extent and distribution of antibodies to infections, especially SARS-CoV-2, in areas where epidemiological information is limited.


Assuntos
COVID-19 , Criança , Humanos , Idoso , Timor-Leste , COVID-19/epidemiologia , SARS-CoV-2 , Estudos Soroepidemiológicos , Anticorpos , Anticorpos Antivirais
11.
Lancet Reg Health Southeast Asia ; 11: 100150, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36744276

RESUMO

Timor-Leste is a small nation of 1.3 million people which shares a land border with Indonesia and is 550 km from Darwin, Australia. It is one of the poorest nations in Asia. The National Health Laboratory (NHL) and its network of smaller laboratories in Timor-Leste had limited capacity to perform molecular diagnostic testing before the coronavirus disease 2019 (COVID-19) pandemic began. With the support of international development partners, the NHL rapidly expanded its molecular testing service. From March 2020 to February 2022, over 200,000 molecular tests were performed; COVID-19 testing sites were established in hospital and community health center laboratories and all 13 municipalities, and the number of scientists and technicians at the molecular diagnostic laboratory at the NHL increased from five to 28 between 2019 and 2022. Molecular diagnostic testing for COVID-19 was successfully established at the NHL and in the municipalities. The molecular diagnostic laboratory at NHL is now equipped to respond to not only large-scale COVID-19 testing but also laboratory detection of other infectious diseases, preparing Timor-Leste for future outbreaks or pandemics.

12.
Int J Cosmet Sci ; 34(5): 435-40, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22738140

RESUMO

Several treatments for skin whitening are available today, but few of them are completely adequate, especially owing to the carcinogenic potential attributed to classical drugs like hydroquinone, arbutin and kojic acid. To provide an alternative and safer technology for whitening, we developed two botanical compounds originated from Brazilian biodiversity, an extract of Schinus terebinthifolius Raddi and a linoleic acid fraction isolated from Passiflora edulis oil. The whitening effect of these compounds was assessed using biochemical assays and in vitro models including cellular assays and equivalent skin. The results showed that S. terebinthifolius Raddi extract is able to reduce the tyrosinase activity in vitro, and the combination of this extract with linoleic acid is able to decrease the level of melanin produced by B16 cells cultured with melanocyte-stimulating hormone. Furthermore, melanin was also reduced in human reconstituted epidermis (containing melanocytes) treated with the compounds. The combination of the compounds may provide a synergistic positive whitening effect rather than their isolated use. Finally, we demonstrated that the performance of these mixed compounds is comparable to classical molecules used for skin whitening, as kojic acid. This new natural mixture could be considered an alternative therapeutic agent for treating hyperpigmentation and an effective component in whitening cosmetics.


Assuntos
Anacardiaceae/química , Epiderme/efeitos dos fármacos , Ácido Linoleico/farmacologia , Melaninas/antagonistas & inibidores , Melaninas/biossíntese , Passiflora/química , Extratos Vegetais/farmacologia , Preparações Clareadoras de Pele/farmacologia , Animais , Células 3T3 BALB , Brasil , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Epiderme/enzimologia , Epiderme/metabolismo , Feminino , Humanos , Técnicas In Vitro , Concentração Inibidora 50 , Masculino , Melaninas/metabolismo , Melanócitos/efeitos dos fármacos , Melanócitos/enzimologia , Melanócitos/metabolismo , Melanoma Experimental/metabolismo , Camundongos , Monofenol Mono-Oxigenase/antagonistas & inibidores , Monofenol Mono-Oxigenase/metabolismo
13.
Free Radic Biol Med ; 193(Pt 2): 779-786, 2022 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-36403737

RESUMO

Nitrite has been viewed essentially as an inert metabolic endpoint of nitric oxide (•NO). However, under certain conditions, nitrite can be a source of •NO. In the brain, this alternative source of •NO production independent of nitric oxide synthase activity may be particularly relevant in ischemia/reperfusion (I/R), where low oxygen availability limits enzymatic production of •NO. Notably, in vivo concentration of nitrite can be easily increased with diet, through the ingestion of nitrate-rich foods, opening the window for a therapeutic intervention based on diet. Considering the modulation of mitochondrial respiration by •NO, we have hypothesized that the protective action of nitrite in I/R may also result from modulation of mitochondrial function. We used high-resolution respirometry to evaluate the effects of nitrite in two in vitro models of I/R. In both cases, an increase in oxygen flux was observed following reoxygenation, a phenomenon that has been coined "oxidative burst". The amplitude of this "oxidative burst" was decreased by nitrite in a concentration-dependent manner. Additionally, a pilot in vivo study in which animals received a nitrate-rich diet as a strategy to increase circulating and tissue levels of nitrite also revealed that the "oxidative burst" was decreased in the nitrate-treated animals. These results may provide mechanistic support to the observation of a protective effect of nitrite in situations of brain ischemia.


Assuntos
Nitratos , Nitritos , Animais , Reperfusão , Isquemia , Óxido Nítrico , Oxigênio , Estresse Oxidativo
14.
Brain ; 133(Pt 3): 771-86, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20157015

RESUMO

Additional neurological features have recently been described in seven families transmitting pathogenic mutations in OPA1, the most common cause of autosomal dominant optic atrophy. However, the frequency of these syndromal 'dominant optic atrophy plus' variants and the extent of neurological involvement have not been established. In this large multi-centre study of 104 patients from 45 independent families, including 60 new cases, we show that extra-ocular neurological complications are common in OPA1 disease, and affect up to 20% of all mutational carriers. Bilateral sensorineural deafness beginning in late childhood and early adulthood was a prominent manifestation, followed by a combination of ataxia, myopathy, peripheral neuropathy and progressive external ophthalmoplegia from the third decade of life onwards. We also identified novel clinical presentations with spastic paraparesis mimicking hereditary spastic paraplegia, and a multiple sclerosis-like illness. In contrast to initial reports, multi-system neurological disease was associated with all mutational subtypes, although there was an increased risk with missense mutations [odds ratio = 3.06, 95% confidence interval = 1.44-6.49; P = 0.0027], and mutations located within the guanosine triphosphate-ase region (odds ratio = 2.29, 95% confidence interval = 1.08-4.82; P = 0.0271). Histochemical and molecular characterization of skeletal muscle biopsies revealed the presence of cytochrome c oxidase-deficient fibres and multiple mitochondrial DNA deletions in the majority of patients harbouring OPA1 mutations, even in those with isolated optic nerve involvement. However, the cytochrome c oxidase-deficient load was over four times higher in the dominant optic atrophy + group compared to the pure optic neuropathy group, implicating a causal role for these secondary mitochondrial DNA defects in disease pathophysiology. Individuals with dominant optic atrophy plus phenotypes also had significantly worse visual outcomes, and careful surveillance is therefore mandatory to optimize the detection and management of neurological disability in a group of patients who already have significant visual impairment.


Assuntos
Doenças do Sistema Nervoso Central/complicações , GTP Fosfo-Hidrolases/genética , Atrofia Óptica Autossômica Dominante/complicações , Adolescente , Adulto , Idoso , Doenças do Sistema Nervoso Central/genética , Doenças do Sistema Nervoso Central/metabolismo , Doenças do Sistema Nervoso Central/patologia , Criança , Estudos de Coortes , DNA Mitocondrial/análise , DNA Mitocondrial/genética , Família , Feminino , Heterozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Mutação , Atrofia Óptica Autossômica Dominante/genética , Atrofia Óptica Autossômica Dominante/metabolismo , Atrofia Óptica Autossômica Dominante/patologia , Fenótipo , Adulto Jovem
15.
Free Radic Biol Med ; 162: 500-513, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33186742

RESUMO

The small and diffusible free radical nitric oxide (•NO) has fascinated biological and medical scientists since it was promoted from atmospheric air pollutant to biological ubiquitous signaling molecule. Its unique physical chemical properties expand beyond its radical nature to include fast diffusion in aqueous and lipid environments and selective reactivity in a biological setting determined by bioavailability and reaction rate constants with biomolecules. In the brain, •NO is recognized as a key player in numerous physiological processes ranging from neurotransmission/neuromodulation to neurovascular coupling and immune response. Furthermore, changes in its bioactivity are central to the molecular pathways associated with brain aging and neurodegeneration. The understanding of •NO bioactivity in the brain, however, requires the knowledge of its concentration dynamics with high spatial and temporal resolution upon stimulation of its synthesis. Here we revise our current understanding of the role of neuronal-derived •NO in brain physiology, aging and degeneration, focused on changes in the extracellular concentration dynamics of this free radical and the regulation of bioenergetic metabolism and neurovascular coupling.


Assuntos
Acoplamento Neurovascular , Óxido Nítrico , Neurônios , Transdução de Sinais
16.
Artigo em Inglês | MEDLINE | ID: mdl-29614328

RESUMO

The Publisher regrets that this article is an accidental duplication of an article that has already been published, https://doi.org/10.1016/j.jpainsymman.2018.03.023. The duplicate article has therefore been withdrawn. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal.

17.
Oncogene ; 36(49): 6815-6822, 2017 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-28806398

RESUMO

The oncogenic transcription factor c-MYC (MYC) is deregulated and often overexpressed in more than 50% of cancers. MYC deregulation is associated with poor prognosis and aggressive disease, suggesting that the development of therapeutic inhibitors targeting MYC would markedly impact patient outcome. MYC is highly regulated, with a protein and mRNA half-life of ~30 min. The most extensively studied pathway regulating MYC protein stability involves ubiquitylation and proteasomal degradation mediated by the E3-ligase, SCFFbxw7. Here we provide evidence for an SCFFbxw7-independent regulatory mechanism centred on the highly conserved lysine-52 (K52) within MYC Box I. This residue has been shown to be post-translationally modified by both ubiquitylation and SUMOylation, hinting at the interplay of post-translational modifications at this site and the importance of this residue. We demonstrate that mutation of K52 to arginine (R) renders the MYC protein more labile. Mechanistically, we show that the degradation pathway regulated by K52 is independent of the Cullin-RING ligase family of E3-ligases, which includes not only the canonical SCFFbxw7 but also other known MYC-targeting E3-ligases, such as SCFSkp2, SCFßTCRP, SCFFbxo28 and DCXTRUSS. Taken together, our data identify a novel regulatory pathway centred on K52 that may be exploited for the development of anti-MYC therapeutics.


Assuntos
Proteína 7 com Repetições F-Box-WD/metabolismo , Lisina/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Ubiquitinação , Animais , Arginina/genética , Arginina/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Proteína Duplacortina , Células HCT116 , Células HEK293 , Meia-Vida , Humanos , Immunoblotting , Lisina/genética , Mutação de Sentido Incorreto , Estabilidade Proteica , Proteínas Proto-Oncogênicas c-myc/genética , Ratos
18.
Porto Biomed J ; 2(1): 18-22, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-32258579

RESUMO

This work proposes a novel approach to assess spinal curvature, by using Microsoft's Kinect™ to obtain 3D reconstructed models of subject's dorsal skin surface in different postures. This method is non-invasive, radiation-free and low-cost. The trial tests here presented intended to evaluate the reliability of this approach, by assessing the tendency of 98 volunteers to present scoliosis. The shoulder height difference was calculated for each subject's scan, by quantifying the angular slope of a line crossing both scapulae. The volunteers' average age was 24.7 years. Results showed that 68.37% of the volunteers revealed differences higher than 1° between the shoulders, having that their record in what concerns to loads and lesions proved to increase the angular slope. This initial approach shall establish the grounds for assessing spinal posture in pre-clinical or industrial ergonomics scans. Further studies shall include comparison versus traditional imaging methods and experienced clinical evaluation.

19.
Oncogene ; 36(49): 6830-6837, 2017 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-28806396

RESUMO

Developing therapeutics to effectively inhibit the MYC oncoprotein would mark a key advance towards cancer patient care as MYC is deregulated in over 50% of human cancers. MYC deregulation is correlated with aggressive disease and poor patient outcome. Despite strong evidence in mouse models that inhibiting MYC would significantly impact tumour cell growth and patient survival, traditional approaches have not yet yielded the urgently needed therapeutic agents that directly target MYC. MYC functions through its interaction with MAX to regulate gene transcription by binding to E-box DNA response elements of MYC target genes. Here we used a structure-based strategy to design ME47, a small minimalist hybrid protein (MHP) able to disrupt the MAX:E-box interaction/binding and block transcriptional MYC activity. We show that inducing ME47 expression in established tumour xenografts inhibits tumour growth and decreases cellular proliferation. Mechanistically, we show by chromatin immunoprecipitation that ME47 binds to E-box binding sites of MYC target genes. Moreover, ME47 occupancy decreases MYC:DNA interaction at its cognate E-box binding sites. Taken together, ME47 is a prototypic MHP inhibitor that antagonizes tumour cell growth in vitro and in vivo and inhibits the interaction of MYC with DNA E-box elements. These results support ME47's role as a MYC inhibitor and suggest that MHPs provide an alternative therapeutic targeting system that can be used to target transcription factors important in human diseases, including cancer.


Assuntos
Elementos E-Box/genética , Motivos de Nucleotídeos/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto/métodos , Animais , Ligação Competitiva , Linhagem Celular Tumoral , Imunoprecipitação da Cromatina , Células HEK293 , Humanos , Camundongos Endogâmicos NOD , Camundongos SCID , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Regiões Promotoras Genéticas/genética , Ligação Proteica , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Recombinantes de Fusão/genética , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia , Carga Tumoral/genética
20.
Artigo em Inglês | MEDLINE | ID: mdl-28029546

RESUMO

The development and performance evaluation of a method for the simultaneous determination of six antipsychotic drugs in hospital effluents and wastewater treatment plants (WWTP) samples are herein presented. The method involves an off-line mixed mode (reversed-phase and strong cation exchange) solid phase extraction (SPE) with gas chromatography (GC) coupled to tandem mass spectrometry (MS/MS). The present methodology was validated following internationally accepted criteria, and the studied parameters included selectivity, linearity, limits of detection (LOD) and quantitation (LLOQ), instrumental limits, precision and accuracy, stability and recovery. The procedure was linear for concentrations ranging from 0.1 to 10µg/L (0.02 to 2µg/L for haloperidol), with determination coefficients higher than 0.99 for all analytes. Intra- and inter-day precision was lower than 15% for all analytes at the studied concentrations, while accuracy remained between a ±15% interval. Recoveries ranged from 31% to 83%. Low LODs were achieved, between 2 and 10ng/L, allowing a reliable identification of all analytes at trace levels, using only 50mL as sample volume. All studied parameters complied with the defined criteria and the method was successfully applied to gather preliminary results of the determination of antipsychotics on hospital effluents and on influent and effluent of WWTPs, opening perspectives for the study of their fate in the aquatic environment.

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