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1.
Nat Chem ; 16(4): 658-665, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38216752

RESUMO

The activation of dioxygen at haem and non-haem metal centres, and subsequent functionalization of unactivated C‒H bonds, has been a focal point of much research. In iron-mediated oxidation reactions, O2 binding at an iron(II) centre is often accompanied by an oxidation of the iron centre. Here we demonstrate dioxygen activation by sodium tetraphenylborate and protons in the presence of an iron(II) complex to form a reactive radical species, whereby the iron oxidation state remains unaltered in the presence of a highly oxidizing phenoxyl radical and O2. This complex, containing an unusual iron(II)-phenoxyl radical motif, represents an elusive example of a spectroscopically characterized oxygen-derived iron(II)-reactive intermediate during chemical and biological dioxygen activation at haem and non-haem iron active centres. The present report opens up strategies for the stabilization of a phenoxyl radical cofactor, with its full oxidizing capabilities, to act as an independent redox centre next to an iron(II) site during substrate oxidation reactions.

2.
Angew Chem Int Ed Engl ; 62(10): e202209437, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36541062

RESUMO

Diiron cofactors in enzymes perform diverse challenging transformations. The structures of high valent intermediates (Q in methane monooxygenase and X in ribonucleotide reductase) are debated since Fe-Fe distances of 2.5-3.4 Šwere attributed to "open" or "closed" cores with bridging or terminal oxido groups. We report the crystallographic and spectroscopic characterization of a FeIII 2 (µ-O)2 complex (2) with tetrahedral (4C) centres and short Fe-Fe distance (2.52 Å), persisting in organic solutions. 2 shows a large Fe K-pre-edge intensity, which is caused by the pronounced asymmetry at the TD FeIII centres due to the short Fe-µ-O bonds. A ≈2.5 ŠFe-Fe distance is unlikely for six-coordinate sites in Q or X, but for a Fe2 (µ-O)2 core containing four-coordinate (or by possible extension five-coordinate) iron centres there may be enough flexibility to accommodate a particularly short Fe-Fe separation with intense pre-edge transition. This finding may broaden the scope of models considered for the structure of high-valent diiron intermediates formed upon O2 activation in biology.


Assuntos
Ferro , Oxigênio , Ferro/química , Análise Espectral , Cristalografia por Raios X , Oxigênio/química , Oxirredução
3.
J Neurooncol ; 161(1): 165-174, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36525166

RESUMO

PURPOSE: Astrocytomas are a type of malignant brain tumor with an unfavorable clinical course. The impact of AGT and MGMT somatic variants in the prognosis of astrocytoma is unknown, and it is controversial for TP53. Moreover, there is a lack of knowledge regarding the molecular characteristics of astrocytomas in Mexican patients. METHODS: We studied 48 Mexican patients, men and women, with astrocytoma (discovery cohort). We performed DNA deep sequencing in tumor samples, targeting AGT, MGMT and TP53, and we studied MGMT gene promoter methylation status. Then we compared our findings to a cohort which included data from patients with astrocytoma from The Cancer Genome Atlas (validation cohort). RESULTS: In the discovery cohort, we found a higher number of somatic variants in AGT and MGMT than in the validation cohort (10.4% vs < 1%, p < 0.001), and, in both cohorts, we observed only women carried variants AGT variants. We also found that the presence of either MGMT variant or promoter methylation was associated to better survival and response to chemotherapy, and, in conjunction with TP53 variants, to progression-free survival. CONCLUSIONS: The occurrence of AGT variants only in women expands our knowledge about the molecular differences in astrocytoma between men and women. The increased prevalence of AGT and MGMT variants in the discovery cohort also points towards possible distinctions in the molecular landscape of astrocytoma among populations. Our findings warrant further study.


Assuntos
Astrocitoma , Neoplasias Encefálicas , Feminino , Humanos , Masculino , Astrocitoma/patologia , Biomarcadores , Neoplasias Encefálicas/patologia , DNA/uso terapêutico , Metilação de DNA , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Mutação , Prognóstico , Análise de Sequência de DNA , Proteína Supressora de Tumor p53/genética , Proteínas Supressoras de Tumor/genética
4.
Rev. colomb. psiquiatr ; 51(2): 163-166, abr.-jun. 2022. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1394987

RESUMO

ABSTRACT Objective: Inhalant users may develop toluene leukoencephalopathy, a devastating neuropsychiatric disorder. We present a case of toluene-induced damage to the corticospinal and the corticonuclear tracts, which presented with involuntary emotional expression dis-order. Methods: Case study of a 20-year-old man with a 3-year history of frequent solvent abuse was admitted to the Neuropsychiatry Unit of the National Institute of Neurology and Neurosurgery because "he could not speak or walk" but would keep "laughing and crying without reason". Results: Neuropsychiatric examination revealed pathological laughter and crying, facial and speech apraxia, a bilateral pyramidal syndrome, and lack of control of urinary sphincter. Magnetic resonance imaging revealed a highly selective bilateral damage to the pyramidal system and the somatosensory pathway. SPECT imaging showed left fronto-parietal hypoperfusion. Conclusions: This document provides support for the understanding of involuntary emotional expression disorders as a differential diagnosis in the clinical practice of psychiatrists, as well as the functional anatomy of these conditions.


RESUMEN Objetivo: Los usuarios de inhalantes pueden contraer leucoencefalopatía por tolueno, un trastorno neuropsiquiátrico devastador. Se presenta un caso de daño inducido por tolueno en el tracto corticoespinal y corticonuclear, que se manifestó con un trastorno involuntario de la expresión emocional. Métodos: Un varón de 20 años con antecedente de 3 años de abuso de solventes ingresó en la Unidad de Neuropsiquiatría del Instituto Nacional de Neurología y Neurocirugía porque «no podía hablar ni caminar¼ y presentaba episodios súbitos de risa y llanto sin razón aparente. Resultados: La valoración neuropsiquiátrica reveló risa y llanto patológicos, apraxia facial y fonatoria, síndrome piramidal bilateral y ausencia de control del esfínter urinario. La resonancia magnética cerebral mostró un daño bilateral muy selectivo del sistema piramidal y la vía somatosensorial. La imagen de tomografía computarizada por emisión monofotónica mostró hipoperfusión frontoparietal izquierda. Conclusiones: Este documento proporciona apoyo para la comprensión de los trastornos de la expresión emocional involuntaria como diagnóstico diferencial en la práctica clínica de los psiquiatras, así como de la anatomía funcional de estas condiciones.

5.
Cell Mol Neurobiol ; 41(6): 1285-1297, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32535722

RESUMO

Astrocytoma is the most common type of primary brain tumor. The risk factors for astrocytoma are poorly understood; however, germline genetic variants account for 25% of the risk of developing gliomas. In this study, we assessed the risk of astrocytoma associated with variants in AGT, known by its role in angiogenesis, TP53, a well-known tumor suppressor and the DNA repair gene MGMT in a Mexican population. A case-control study was performed in 49 adult Mexican patients with grade II-IV astrocytoma. Sequencing of exons and untranslated regions of AGT, MGMT, and TP53 from was carried in an Ion Torrent platform. Individuals with Mexican Ancestry from the 1000 Genomes Project were used as controls. Variants found in our cohort were then assessed in a The Cancer Genome Atlas astrocytoma pan-ethnic validation cohort. Variants rs1926723 located in AGT (OR 2.74, 1.40-5.36 95% CI), rs7896488 in MGMT (OR 3.43, 1.17-10.10 95% CI), and rs4968187 in TP53 (OR 2.48, 1.26-4.88 95% CI) were significantly associated with the risk of astrocytoma after multiple-testing correction. This is the first study where the AGT rs1926723 variant, TP53 rs4968187, and MGMT rs7896488 were found to be associated with the risk of developing an astrocytoma.


Assuntos
Angiotensinogênio/genética , Astrocitoma/genética , Neoplasias Encefálicas/genética , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Variação Genética/genética , Proteína Supressora de Tumor p53/genética , Proteínas Supressoras de Tumor/genética , Adulto , Astrocitoma/epidemiologia , Astrocitoma/patologia , Neoplasias Encefálicas/epidemiologia , Neoplasias Encefálicas/patologia , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Masculino , México/epidemiologia , Pessoa de Meia-Idade
6.
Neuro Oncol ; 23(4): 599-610, 2021 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-33249487

RESUMO

BACKGROUND: Glioblastomas (GBMs) are the main primary brain tumors in adults with almost 100% recurrence rate. Patients with lateral ventricle proximal GBMs (LV-GBMs) exhibit worse survival compared to distal locations for unknown reasons. One hypothesis is the proximity of these tumors to the cerebrospinal fluid (CSF) and its chemical cues that can regulate cellular phenotype. We therefore investigated the role of CSF on GBM gene expression and the role of a CSF-induced gene, SERPINA3, in GBM malignancy in vitro and in vivo. METHODS: We utilized human CSF and GBM brain tumor-initiating cells (BTICs). We determined the impact of SERPINA3 expression in glioma patients using The Cancer Genome Atlas (TCGA) database. SERPINA3 expression changes were evaluated at mRNA and protein levels. The effects of knockdown (KD) and overexpression (OE) of SERPINA3 on cell migration, viability and cell proliferation were evaluated. Stem cell characteristics on KD cells were evaluated by differentiation and colony formation experiments. Tumor growth was studied by intracranial and flank injections. RESULTS: GBM-CSF increased BTIC migration accompanied by upregulation of the SERPINA3 gene. In patient samples and TCGA data, we observed SERPINA3 to correlate directly with brain tumor grade and indirectly with GBM patient survival. SERPINA3 KD induced a decrease in cell proliferation, migration, invasion, and stem cell characteristics, while SERPINA3 OE increased cell migration. In vivo, SERPINA3 KD BTICs showed increased survival in a murine model. CONCLUSIONS: SERPINA3 plays a key role in GBM malignancy and its inhibition results in a better outcome using GBM preclinical models.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Células-Tronco Neoplásicas , alfa 1-Antiquimotripsina , Adulto , Animais , Neoplasias Encefálicas/genética , Linhagem Celular Tumoral , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Glioblastoma/genética , Humanos , Camundongos , Serpinas
7.
Nat Commun ; 11(1): 1747, 2020 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-32269263

RESUMO

Receptor interacting protein kinase 1 (RIPK1) regulates cell death and inflammatory responses downstream of TNFR1 and other receptors, and has been implicated in the pathogenesis of inflammatory and degenerative diseases. RIPK1 kinase activity induces apoptosis and necroptosis, however the mechanisms and phosphorylation events regulating RIPK1-dependent cell death signaling remain poorly understood. Here we show that RIPK1 autophosphorylation at serine 166 plays a critical role for the activation of RIPK1 kinase-dependent apoptosis and necroptosis. Moreover, we show that S166 phosphorylation is required for RIPK1 kinase-dependent pathogenesis of inflammatory pathologies in vivo in four relevant mouse models. Mechanistically, we provide evidence that trans autophosphorylation at S166 modulates RIPK1 kinase activation but is not by itself sufficient to induce cell death. These results show that S166 autophosphorylation licenses RIPK1 kinase activity to induce downstream cell death signaling and inflammation, suggesting that S166 phosphorylation can serve as a reliable biomarker for RIPK1 kinase-dependent pathologies.


Assuntos
Apoptose , Inflamação/metabolismo , Inflamação/patologia , Fosfosserina/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Alanina Transaminase/metabolismo , Animais , Células da Medula Óssea/citologia , Colite/patologia , Genótipo , Hepatite/patologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Macrófagos/metabolismo , Camundongos Endogâmicos C57BL , Mutação/genética , Neoplasias/patologia , Fosforilação , Sepse/patologia , Pele/patologia , Fator de Necrose Tumoral alfa
8.
J Am Chem Soc ; 142(13): 5924-5928, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32168447

RESUMO

In soluble methane monooxygenase enzymes (sMMO), dioxygen (O2) is activated at a diiron(II) center to form an oxodiiron(IV) intermediate Q that performs the challenging oxidation of methane to methanol. An analogous mechanism of O2 activation at mono- or dinuclear iron centers is rare in the synthetic chemistry. Herein, we report a mononuclear non-heme iron(II)-cyclam complex, 1-trans, that activates O2 to form the corresponding iron(IV)-oxo complex, 2-trans, via a mechanism reminiscent of the O2 activation process in sMMO. The conversion of 1-trans to 2-trans proceeds via the intermediate formation of an iron(III)-superoxide species 3, which could be trapped and spectroscopically characterized at -50 °C. Surprisingly, 3 is a stronger oxygen atom transfer (OAT) agent than 2-trans; 3 performs OAT to 1-trans or PPh3 to yield 2-trans quantitatively. Furthermore, 2-trans oxidizes the aromatic C-H bonds of 2,6-di-tert-butylphenol, which, together with the strong OAT ability of 3, represents new domains of oxoiron(IV) and superoxoiron(III) reactivities.


Assuntos
Compostos Heterocíclicos/metabolismo , Compostos de Ferro/metabolismo , Oxigênio/metabolismo , Oxigenases/metabolismo , Compostos Heterocíclicos/química , Compostos de Ferro/química , Modelos Moleculares , Oxirredução , Oxigênio/química , Superóxidos/química , Superóxidos/metabolismo
9.
Clin Neurol Neurosurg ; 188: 105588, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31715425

RESUMO

OBJECTIVE: Optic Neuritis (ON) might unfold either as a single intracranial neuritis or as multiple sclerosis, a widespread demyelinating disorder. Different herpes viruses have been proposed as potential participants in the etiology of multiple sclerosis (MS). To analyze the potential presence of herpes viruses in blood and subarachnoid area at the time of ON and contrast the findings according to long-term evolution either as intracranial neuritis or as progression to multiple sclerosis. PATIENTS AND METHODS: In a prospective investigation we searched the presence of DNA from 5 herpes viruses (HSV-1, HSV-2, VZV, EBV and HHV6) in CSF and blood lymphocytes from 54 patients with ON, patients were followed 62 ±â€¯3 months; those who developed MS were separated from those with ephemeral ON. Long-term prognosis of ON was related to DNA findings. RESULTS: As compared with controls, DNA from HSV-1 was significantly more frequent in CSF and blood from cases with ON; VZV and HSV-2 were found only in CSF; EBV was found only in blood samples (p < 0.006). CONCLUSIONS: Our results point out the potential participation of HSV, VZV and EBV in ON; suggesting the intervention of various herpes viruses as triggering agents of autoimmunity. However, the number of positive cases was minor than negative cases. Also, our results suggest that the etiological mechanisms in ON could be similar to those of neuritis of the facial nerve (Bell's palsy).


Assuntos
DNA Viral/líquido cefalorraquidiano , Infecções por Herpesviridae/epidemiologia , Herpesviridae/genética , Neurite Óptica/virologia , Adulto , Paralisia de Bell/virologia , DNA Viral/sangue , Infecções por Vírus Epstein-Barr/epidemiologia , Feminino , Herpes Simples/epidemiologia , Herpesvirus Humano 1/genética , Herpesvirus Humano 2/genética , Herpesvirus Humano 3/genética , Herpesvirus Humano 4/genética , Herpesvirus Humano 6/genética , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/fisiopatologia , Neurite Óptica/epidemiologia , Neurite Óptica/metabolismo , Neurite Óptica/fisiopatologia , Prognóstico , Infecções por Roseolovirus/epidemiologia , Infecção pelo Vírus da Varicela-Zoster/epidemiologia , Adulto Jovem
11.
PLoS Negl Trop Dis ; 13(7): e0007501, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31291239

RESUMO

BACKGROUND: Taenia solium cysticercosis is a public health and agricultural problem in many low and middle-income countries where health education, sanitation, pig management practices and meat inspection infrastructure are insufficient. Cysticercosis affects both human and animal health and has important economic consequences. Very few studies have been conducted to evaluate the monetary burden of cysticercosis. This study aimed at estimating the 2015 costs associated with cysticercosis in humans and pigs in Mexico. METHODS: The monetary burden of human cysticercosis was estimated based on costs incurred by living with and treating epilepsy and severe chronic headaches associated with neurocysticercosis (NCC). The estimated cost of porcine cysticercosis took into consideration losses due to the reduction in the price of cysticercosis-infected animals. Epidemiologic and economic data were obtained from the published literature, government reports, and setting-specific questionnaires. Latin hypercube sampling methods were employed to sample the distributions of uncertain parameters and to estimate 95% credible regions (95% CRs). All results are reported in 2015 U.S.$. FINDINGS: The overall monetary burden associated with NCC morbidity was estimated at U.S.$215,775,056 (95% CR U.S.$109,309,560 -U.S.$361,924,224), with U.S.$436 (95% CR: U.S.$296 -U.S.$604) lost per patient. If loss of future years of income and productivity due to NCC-associated deaths was included, this value increased by U.S.$54.26 million, assuming that these individuals earned Mexico's median wage salary. An additional U.S.$19,507,171 (95% CR U.S.$5,734,782 -U.S.$35,913,487) was estimated to be lost due to porcine cysticercosis. CONCLUSIONS: This study suggests that T. solium cysticercosis results in considerable monetary losses to Mexico.


Assuntos
Efeitos Psicossociais da Doença , Cisticercose/economia , Doenças dos Suínos/economia , Adolescente , Adulto , Animais , Cisticercose/complicações , Cisticercose/epidemiologia , Epilepsia/economia , Epilepsia/epidemiologia , Epilepsia/parasitologia , Feminino , Hospitalização/economia , Humanos , Masculino , México/epidemiologia , Neurocisticercose/economia , Neurocisticercose/epidemiologia , Prevalência , Saúde Pública/economia , Anos de Vida Ajustados por Qualidade de Vida , Suínos , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/parasitologia , Taenia solium , Adulto Jovem
12.
Angew Chem Int Ed Engl ; 58(36): 12534-12539, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31246329

RESUMO

The reactivity of a mononuclear high-spin iron(III)-alkylperoxo intermediate [FeIII (t-BuLUrea )(OOCm)(OH2 )]2+ (2), generated from [FeII (t-BuLUrea )(H2 O)(OTf)](OTf) (1) [t-BuLUrea =1,1'-(((pyridin-2-ylmethyl)azanediyl)bis(ethane-2,1-diyl))bis(3-(tert-butyl)urea), OTf=trifluoromethanesulfonate] with cumyl hydroperoxide (CmOOH), toward the C-H and C=C bonds of hydrocarbons is reported. 2 oxygenates the strong C-H bonds of aliphatic substrates with high chemo- and stereoselectivity in the presence of 2,6-lutidine. While 2 itself is a sluggish oxidant, 2,6-lutidine assists the heterolytic O-O bond cleavage of the metal-bound alkylperoxo, giving rise to a reactive metal-based oxidant. The roles of the urea groups on the supporting ligand, and of the base, in directing the selective and catalytic oxygenation of hydrocarbon substrates by 2 are discussed.

13.
ACS Cent Sci ; 5(1): 13-28, 2019 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-30693322

RESUMO

Utilization of O2 as an abundant and environmentally benign oxidant is of great interest in the design of bioinspired synthetic catalytic oxidation systems. Metalloenzymes activate O2 by employing earth-abundant metals and exhibit diverse reactivities in oxidation reactions, including epoxidation of olefins, functionalization of alkane C-H bonds, arene hydroxylation, and syn-dihydroxylation of arenes. Metal-oxo species are proposed as reactive intermediates in these reactions. A number of biomimetic metal-oxo complexes have been synthesized in recent years by activating O2 or using artificial oxidants at iron and manganese centers supported on heme or nonheme-type ligand environments. Detailed reactivity studies together with spectroscopy and theory have helped us understand how the reactivities of these metal-oxygen intermediates are controlled by the electronic and steric properties of the metal centers. These studies have provided important insights into biological reactions, which have contributed to the design of biologically inspired oxidation catalysts containing earth-abundant metals like iron and manganese. In this Outlook article, we survey a few examples of these advances with particular emphasis in each case on the interplay of catalyst design and our understanding of metalloenzyme structure and function.

14.
J Proteomics ; 195: 53-65, 2019 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-30593931

RESUMO

Stable isotope labeling in cell culture (SILAC) was applied for the first time on a lactic acid bacterium strain (L. reuteri CRL1101) for analyzing differential protein expression associated to selenite(Na2SeO3) and selenium nanoparticles (SeNPs) exposure. 57 and 47 proteins were found de-regulated by >1,5 fold in presence of selenite and SeNPs, respectively. Only 16 out of 104 proteins differentially expressed were commonly altered by selenite and SeNPs. The use of a clustered heat map allows us to visualize relations between the de-regulated proteins and exposure conditions. We identified a number of proteins involved in diverse functions and biological processes such as metabolism of carbohydrates, selenium and lipids; folding, sorting and degradation; environmental information and processing. In presence of both, selenite and SeNPs, proteins related to selenium metabolism such as cystathione beta-lyase and oxidoreductases (thioredoxine reductase and NAD/FAD oxidoreductase) were over expressed. Interestingly, the over expression of thioredoxin reductase could protect the host from oxidizing compounds. An over expression of phage proteins and chaperones with selenite was observed; this result and the fact that a lower cell count was detected when selenite was added could indicate that this latter Se species has a more deleterious effect than the nanoparticles.


Assuntos
Proteínas de Bactérias/metabolismo , Limosilactobacillus reuteri/metabolismo , Nanopartículas Metálicas/química , Proteômica , Ácido Selenioso/farmacologia , Selênio/química , Oxirredução/efeitos dos fármacos
15.
PLoS One ; 13(11): e0206590, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30383794

RESUMO

INTRODUCTION: Renin-angiotensin system (RAS) in brain cancer represents a scarcely explored field in neuro-oncology. Recently, some pre- and clinical studies have reported that RAS components play a relevant role in the development and behavior of gliomas. The angiotensinogen (AGT) rs5050 genetic variant has been identified as a crucial regulator of the transcription of AGT mRNA, which makes it a logical and promising target of research. The aim of this study was to determine the relationship between the AGT rs5050 genetic variant in blood with prognosis in astrocytoma. METHODS: A prospective pilot study was performed on forty-eight astrocytoma patients, who received the standard-of-care treatment. Blood samples were taken prior to surgery and DNA was sequenced using Ion Torrent next-generation sequencing and analyzed by Ion Reporter software. Descriptive, bivariate, multivariate, and survival analyses were performed using SPSS v21, STATA 12 and GraphPad Prism 7. RESULTS: Median follow-up was 41 months (range 1-48). Survival analysis showed a significant difference between the rs5050 genotypes (p = .05). We found lower survival rates in individuals with the GG-genotype of rs5050 AGT compared to patients with the TT- and TG-genotype (2 months vs. 11.5 months, respectively [p = .01]). In bivariate and multivariate analyses, GG-genotype was negatively associated with survival. CONCLUSIONS: In patients with astrocytoma, AGT rs5050 GG-genotype was associated with poor prognosis. We propose this germline genetic variant as a complementary biomarker, which can be detected practically and safely in blood samples or saliva.


Assuntos
Angiotensinogênio/genética , Astrocitoma/diagnóstico , Astrocitoma/genética , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/genética , Mutação em Linhagem Germinativa , Adulto , Idoso , Angiotensinogênio/sangue , Astrocitoma/mortalidade , Astrocitoma/terapia , Biomarcadores Tumorais/genética , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/terapia , Feminino , Seguimentos , Frequência do Gene , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Prognóstico , Estudos Prospectivos , Análise de Sobrevida , Adulto Jovem
16.
Angew Chem Int Ed Engl ; 57(45): 14883-14887, 2018 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-30204293

RESUMO

The formation and detailed spectroscopic characterization of the first biuret-containing monoanionic superoxido-NiII intermediate [LNiO2 ]- as the Li salt [2; L=MeN[C(=O)NAr)2 ; Ar=2,6-iPr2 C6 H3 )] is reported. It results from oxidation of the corresponding [Li(thf)3 ]2 [LNiII Br2 ] complex M with excess H2 O2 in the presence of Et3 N. The [LNiO2 ]- core of 2 shows an unprecedented nucleophilic reactivity in the oxidative deformylation of aldehydes, in stark contrast to the electrophilic character of the previously reported neutral Nacnac-containing superoxido-NiII complex 1, [L'NiO2 ] (L'=CH(CMeNAr)2 ). According to density-functional theory (DFT) calculations, the remarkably different behaviour of 1 versus 2 can be attributed to their different charges and a two-state reactivity, in which a doublet ground state and a nearby spin-polarized doublet excited-state both contribute in 1 but not in 2. The unexpected nucleophilicity of the superoxido-NiII core of 2 suggests that such a reactivity may also play a role in catalytic cycles of Ni-containing oxygenases and oxidases.


Assuntos
Complexos de Coordenação/química , Lítio/química , Níquel/química , Superóxidos/química , Modelos Moleculares , Oxirredução , Oxirredutases/química , Oxigênio/química , Oxigenases/química , Teoria Quântica , Sais/química
17.
Rev Invest Clin ; 70(2): 68-75, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29718010

RESUMO

BACKGROUND: Retinal vasculopathy with cerebral leukodystrophy (RVCL) is an adult-onset, autosomal dominant disease involving microvessels of the brain and eye resulting in central nervous system degeneration with visual disturbances, stroke, motor impairment, and cognitive decline. Frameshift mutations at the C-terminus of TREX1 gene are the molecular cause of this disorder. OBJECTIVES: The objective of this study is to present the different clinical manifestations of RVCL in three-related patients and to investigate the presence of TREX1 mutation in the extended genealogy. METHODS: Multidisciplinary testing was performed in three related patients. Based on their family history, the study was extended to 34 relatives from the same small community. Neurological evaluation, sequencing of TREX1, and presymptomatic diagnosis were offered to all participants. RESULTS: The patients exhibited the heterozygous TREX1 mutation p.V235Gfs*6, but with phenotypic variability. In addition, 15 relatives were identified as pre-manifest mutation carriers. The remaining participants did not carry the mutation. CONCLUSIONS: This is the figrst report of a large Mexican genealogy with RVCL, where the same TREX1 mutation causes a variation in organ involvement and clinical progression. The early identification and follow-up of individuals at risk may help provide insights into the basis for this variability in presentation.


Assuntos
Variação Biológica da População , Exodesoxirribonucleases/genética , Doenças Desmielinizantes Hereditárias do Sistema Nervoso Central/fisiopatologia , Fosfoproteínas/genética , Doenças Retinianas/fisiopatologia , Doenças Vasculares/fisiopatologia , Feminino , Doenças Desmielinizantes Hereditárias do Sistema Nervoso Central/diagnóstico , Doenças Desmielinizantes Hereditárias do Sistema Nervoso Central/genética , Heterozigoto , Humanos , Masculino , México , Pessoa de Meia-Idade , Mutação , Doenças Retinianas/diagnóstico , Doenças Retinianas/genética , Doenças Vasculares/diagnóstico , Doenças Vasculares/genética
18.
Artigo em Inglês | MEDLINE | ID: mdl-29846471

RESUMO

The objective of this study was to estimate the direct costs associated with the diagnosis and treatment of neurocysticercosis (NCC) during pre-hospitalization, hospitalization, and post-hospitalization periods for 108 NCC patients treated at the Instituto Nacional de Neurologia y Neurocirugia (INNN) in Mexico City, Mexico. Information on clinical manifestations, diagnostic tests, hospitalizations, surgical procedures, prescription medication, and other treatments was collected via medical chart reviews. Uncertain values for costs and frequency of treatments were imputed using bootstrap techniques. The average per-patient pre-hospitalization and hospitalization costs were US$ 257 (95% CI: 185 - 329) and US$ 2,576 (95% CI: 2,244 - 2,908), respectively. Post-hospitalization costs tended to decrease over time, with estimates for the first five years post-hospitalization of US$ 475 (95% CI: 423 - 527), US$ 228 (95% CI: 167 - 288), US$ 157 (95% CI: 111 - 202), US$ 150 (95% CI: 106 - 204), and US$ 91 (95% CI: 27 - 154), respectively. NCC results in a significant economic burden for patients requiring hospitalization, with this burden continuing years post-hospitalization.


Assuntos
Efeitos Psicossociais da Doença , Custos de Cuidados de Saúde/estatística & dados numéricos , Hospitalização/economia , Neurocisticercose/economia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , México , Pessoa de Meia-Idade , Encaminhamento e Consulta/economia , Adulto Jovem
19.
Cent Nerv Syst Agents Med Chem ; 18(1): 8-15, 2018 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-26915659

RESUMO

INTRODUCTION: Multiple Sclerosis (MS) is a chronic, inflammatory, neurodegenerative demyelinating disease of the central nervous system (CNS). Unfortunately, MS causes important disability in young adults and its prevalence is increasing. While the etiology of MS etiology is not completely understood, it seems to be a multifactorial entity that is influenced by both genetic and epigenetic modifications. Epigenetic mechanisms add or remove different chemical groups for the activation or inhibition of gene expression to block the production of proinflammatory proteins. It is truly important to identify the factors that can trigger epigenetic changes in MS to complement the therapeutic approach, prevent disability and improve patients quality of life. Here, we have conducted a review of external factors that influence in MS and their epigenetic mechanisms. For example, hypomethylation can promote changes in the myelin and subsequent autoimmune reactions. Therapeutic tools can be used, including the histone deacetylase inhibitor Trichostatin A, which ameliorates demyelinating diseases in rodents. However, drugs are not only the therapeutic option: recent studies have also evaluated the therapeutic potential of several bioactive dietary components in neurodegeneration and axonal dysfunction. Numerous food-derived molecules exert important metabolic actions. These molecules include plant polyphenols such as catechins and isoflavones, Ω-3 and Ω-6 polyunsaturated fatty acids, short-chain fatty acids, sulfur-containing compounds such as dally sulfide and other compounds. Antioxidant and anti-inflammatory components in the diet involve transcription factors as well. However, many external factors have shown to influence MS, although no specific epigenetic mechanisms are known. CONCLUSION: In this review, we gather both established and new evidences about the genetic, epigenetic and environmental factors influencing MS and the dietary components that could modulate MS relapse and progression.


Assuntos
Antioxidantes/administração & dosagem , Epigênese Genética/fisiologia , Esclerose Múltipla/dietoterapia , Esclerose Múltipla/metabolismo , Polifenóis/administração & dosagem , Animais , Antioxidantes/metabolismo , Metilação de DNA/fisiologia , Ácidos Graxos Ômega-3/administração & dosagem , Ácidos Graxos Ômega-3/metabolismo , Ácidos Graxos Ômega-6/administração & dosagem , Ácidos Graxos Ômega-6/metabolismo , Humanos , Esclerose Múltipla/genética , Polifenóis/metabolismo
20.
J Cell Biol ; 216(3): 675-693, 2017 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-28188211

RESUMO

Mitochondria are essential organelles that host crucial metabolic pathways and produce adenosine triphosphate. The mitochondrial proteome is heterogeneous among tissues and can dynamically change in response to different metabolic conditions. Although the transcriptional programs that govern mitochondrial biogenesis and respiratory function are well known, posttranscriptional regulatory mechanisms remain unclear. In this study, we show that the cytosolic RNA-binding protein clustered mitochondria homologue (CLUH) regulates the expression of a mitochondrial protein network supporting key metabolic programs required under nutrient deprivation. CLUH exerts its function by controlling the stability and translation of target messenger RNAs. In the absence of Cluh, mitochondria are severely depleted of crucial enzymes involved in catabolic energy-converting pathways. CLUH preserves oxidative mitochondrial function and glucose homeostasis, thus preventing death at the fetal-neonatal transition. In the adult liver, CLUH ensures maximal respiration capacity and the metabolic response to starvation. Our results shed new light on the posttranscriptional mechanisms controlling the expression of mitochondrial proteins and suggest novel strategies to tailor mitochondrial function to physiological and pathological conditions.


Assuntos
Mitocôndrias/metabolismo , Biossíntese de Proteínas/fisiologia , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Citosol/metabolismo , Citosol/fisiologia , Metabolismo Energético/fisiologia , Regulação da Expressão Gênica/fisiologia , Homeostase/fisiologia , Metabolismo/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Mitocondriais/metabolismo , Interferência de RNA/fisiologia
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