Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 496
Filtrar
Más filtros

Tipo del documento
Intervalo de año de publicación
1.
Crit Rev Biochem Mol Biol ; 57(2): 133-155, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34608838

RESUMEN

Methyl-Cobalamin (Cbl) derives from dietary vitamin B12 and acts as a cofactor of methionine synthase (MS) in mammals. MS encoded by MTR catalyzes the remethylation of homocysteine to generate methionine and tetrahydrofolate, which fuel methionine and cytoplasmic folate cycles, respectively. Methionine is the precursor of S-adenosyl methionine (SAM), the universal methyl donor of transmethylation reactions. Impaired MS activity results from inadequate dietary intake or malabsorption of B12 and inborn errors of Cbl metabolism (IECM). The mechanisms at the origin of the high variability of clinical presentation of impaired MS activity are classically considered as the consequence of the disruption of the folate cycle and related synthesis of purines and pyrimidines and the decreased synthesis of endogenous methionine and SAM. For one decade, data on cellular and animal models of B12 deficiency and IECM have highlighted other key pathomechanisms, including altered interactome of MS with methionine synthase reductase, MMACHC, and MMADHC, endoplasmic reticulum stress, altered cell signaling, and genomic/epigenomic dysregulations. Decreased MS activity increases catalytic protein phosphatase 2A (PP2A) and produces imbalanced phosphorylation/methylation of nucleocytoplasmic RNA binding proteins, including ELAVL1/HuR protein, with subsequent nuclear sequestration of mRNAs and dramatic alteration of gene expression, including SIRT1. Decreased SAM and SIRT1 activity induce ER stress through impaired SIRT1-deacetylation of HSF1 and hypomethylation/hyperacetylation of peroxisome proliferator-activated receptor-γ coactivator-1α (PGC1α), which deactivate nuclear receptors and lead to impaired energy metabolism and neuroplasticity. The reversibility of these pathomechanisms by SIRT1 agonists opens promising perspectives in the treatment of IECM outcomes resistant to conventional supplementation therapies.


Asunto(s)
5-Metiltetrahidrofolato-Homocisteína S-Metiltransferasa , Sirtuina 1 , 5-Metiltetrahidrofolato-Homocisteína S-Metiltransferasa/genética , 5-Metiltetrahidrofolato-Homocisteína S-Metiltransferasa/metabolismo , Animales , Ácido Fólico , Mamíferos/metabolismo , Metionina , Sirtuina 1/genética , Sirtuina 1/metabolismo , Vitamina B 12/genética , Vitamina B 12/metabolismo , Vitaminas
2.
PLoS Pathog ; 18(6): e1010417, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35731824

RESUMEN

Intracellular pathogens secrete effectors to manipulate their host cells. Histoplasma capsulatum (Hc) is a fungal intracellular pathogen of humans that grows in a yeast form in the host. Hc yeasts are phagocytosed by macrophages, where fungal intracellular replication precedes macrophage lysis. The most abundant virulence factor secreted by Hc yeast cells is Calcium Binding Protein 1 (Cbp1), which is absolutely required for macrophage lysis. Here we take an evolutionary, structural, and cell biological approach to understand Cbp1 function. We find that Cbp1 is present only in the genomes of closely related dimorphic fungal species of the Ajellomycetaceae family that lead primarily intracellular lifestyles in their mammalian hosts (Histoplasma, Paracoccidioides, and Emergomyces), but not conserved in the extracellular fungal pathogen Blastomyces dermatitidis. We observe a high rate of fixation of non-synonymous substitutions in the Cbp1 coding sequences, indicating that Cbp1 is under positive selection. We determine the de novo structures of Hc H88 Cbp1 and the Paracoccidioides americana (Pb03) Cbp1, revealing a novel "binocular" fold consisting of a helical dimer arrangement wherein two helices from each monomer contribute to a four-helix bundle. In contrast to Pb03 Cbp1, we show that Emergomyces Cbp1 orthologs are unable to stimulate macrophage lysis when expressed in the Hc cbp1 mutant. Consistent with this result, we find that wild-type Emergomyces africanus yeast are able to grow within primary macrophages but are incapable of lysing them. Finally, we use subcellular fractionation of infected macrophages and indirect immunofluorescence to show that Cbp1 localizes to the macrophage cytosol during Hc infection, making this the first instance of a phagosomal human fungal pathogen directing an effector into the cytosol of the host cell. We additionally show that Cbp1 forms a complex with Yps-3, another known Hc virulence factor that accesses the cytosol. Taken together, these data imply that Cbp1 is a fungal virulence factor under positive selection that localizes to the cytosol to trigger host cell lysis.


Asunto(s)
Proteínas de Unión al Calcio , Histoplasmosis , Macrófagos , Factores de Virulencia , Animales , Proteínas de Unión al Calcio/genética , Proteínas de Unión al Calcio/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Histoplasma/metabolismo , Histoplasmosis/microbiología , Humanos , Macrófagos/microbiología , Mamíferos , Saccharomyces cerevisiae , Factores de Virulencia/genética , Factores de Virulencia/metabolismo
3.
PLoS Pathog ; 18(9): e1010237, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36174103

RESUMEN

The fungal pathogen Histoplasma capsulatum (Hc) invades, replicates within, and destroys macrophages. To interrogate the molecular mechanisms underlying this interaction, we conducted a host-directed CRISPR-Cas9 screen and identified 361 genes that modify macrophage susceptibility to Hc infection, greatly expanding our understanding of host gene networks targeted by Hc. We identified pathways that have not been previously implicated in Hc interaction with macrophages, including the ragulator complex (involved in nutrient stress sensing), glycosylation enzymes, protein degradation machinery, mitochondrial respiration genes, solute transporters, and the ER membrane complex (EMC). The highest scoring protective hits included the complement C3a receptor (C3aR), a G-protein coupled receptor (GPCR) that recognizes the complement fragment C3a. Although it is known that complement components react with the fungal surface, leading to opsonization and release of small peptide fragments such as C3a, a role for C3aR in macrophage interactions with fungi has not been elucidated. We demonstrated that whereas C3aR is dispensable for macrophage phagocytosis of bacteria and latex beads, it is critical for optimal macrophage capture of pathogenic fungi, including Hc, the ubiquitous fungal pathogen Candida albicans, and the causative agent of Valley Fever Coccidioides posadasii. We showed that C3aR localizes to the early phagosome during Hc infection where it coordinates the formation of actin-rich membrane protrusions that promote Hc capture. We also showed that the EMC promotes surface expression of C3aR, likely explaining its identification in our screen. Taken together, our results provide new insight into host processes that affect Hc-macrophage interactions and uncover a novel and specific role for C3aR in macrophage recognition of fungi.


Asunto(s)
Actinas , Histoplasmosis , Receptores de Complemento/metabolismo , Macrófagos/metabolismo , Histoplasma/genética , Histoplasma/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Fragmentos de Péptidos
4.
Mol Phylogenet Evol ; 194: 108031, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38360081

RESUMEN

Our knowledge of the systematics of the papilionoid legume tribe Brongniartieae has greatly benefitted from recent advances in molecular phylogenetics. The tribe was initially described to include species marked by a strongly bilabiate calyx and an embryo with a straight radicle, but recent research has placed taxa from the distantly related core Sophoreae and Millettieae within it. Despite these advances, the most species-rich genera within the Brongniartieae are still not well studied, and their morphological and biogeographical evolution remains poorly understood. Comprising 35 species, Harpalyce is one of these poorly studied genera. In this study, we present a comprehensive, multi-locus molecular phylogeny of the Brongniartieae, with an increased sampling of Harpalyce, to investigate morphological and biogeographical evolution within the group. Our results confirm the monophyly of Harpalyce and indicate that peltate glandular trichomes and a strongly bilabiate calyx with a carinal lip and three fused lobes are synapomorphies for the genus, which is internally divided into three distinct ecologically and geographically divergent lineages, corresponding to the previously recognized sections. Our biogeographical reconstructions demonstrate that Brongniartieae originated in South America during the Eocene, with subsequent pulses of diversification in South America, Mesoamerica, and Australia. Harpalyce also originated in South America during the Miocene at around 20 Ma, with almost synchronous later diversification in South America and Mexico/Mesoamerica beginning 10 Ma, but mostly during the Pliocene. Migration of Harpalyce from South to North America was accompanied by a biome and ecological shift from savanna to seasonally dry forest.


Asunto(s)
Fabaceae , Filogenia , Fabaceae/genética , Pradera , Bosques , Ecosistema , Teorema de Bayes , Filogeografía
5.
Hum Genomics ; 17(1): 5, 2023 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-36740706

RESUMEN

BACKGROUND: Clinical exome sequencing (CES) provides a comprehensive and effective analysis of relevant disease-associated genes in a cost-effective manner compared to whole exome sequencing. Although several studies have focused on the diagnostic yield of CES, no study has assessed predictors of CES utility among patients with various Mendelian phenotypes. We assessed the effectiveness of CES as a first-level genetic test for molecular diagnosis in patients with a Mendelian phenotype and explored independent predictors of the clinical utility of CES. RESULTS: Between January 2016 and December 2019, 603 patients (426 probands and 177 siblings) underwent CES at the Department of Molecular Medicine of the University Hospital of Nancy. The median age of the probands was 34 years (IQR, 12-48), and the proportion of males was 46.9% (200/426). Adults and children represented 64.8% (276/426) and 35.2% (150/426), respectively. The median test-to-report time was 5.6 months (IQR, 4.1-7.2). CES revealed 203 pathogenic or likely pathogenic variants in 160 patients, corresponding to a diagnostic yield of 37.6% (160/426). Independent predictors of CES utility were criteria strongly suggestive of an extreme phenotype, including pediatric presentation and patient phenotypes associated with an increased risk of a priori probability of a monogenic disorder, the inclusion of at least one family member in addition to the proband, and a CES prescription performed by an expert in the field of rare genetic disorders. CONCLUSIONS: Based on a large dataset of consecutive patients with various Mendelian phenotypes referred for CES as a first-tier genetic test, we report a diagnostic yield of ~ 40% and several independent predictors of CES utility that might improve CES diagnostic efficiency.


Asunto(s)
Pruebas Genéticas , Hermanos , Masculino , Humanos , Secuenciación del Exoma , Pruebas Genéticas/métodos , Fenotipo , Derivación y Consulta
6.
Colorectal Dis ; 26(1): 145-196, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38050857

RESUMEN

AIM: The primary aim of the European Society of Coloproctology (ESCP) Guideline Development Group (GDG) was to produce high-quality, evidence-based guidelines for the management of cryptoglandular anal fistula with input from a multidisciplinary group and using transparent, reproducible methodology. METHODS: Previously published methodology in guideline development by the ESCP has been replicated in this project. The guideline development process followed the requirements of the AGREE-S tool kit. Six phases can be identified in the methodology. Phase one sets the scope of the guideline, which addresses the diagnostic and therapeutic management of perianal abscess and cryptoglandular anal fistula in adult patients presenting to secondary care. The target population for this guideline are healthcare practitioners in secondary care and patients interested in understanding the clinical evidence available for various surgical interventions for anal fistula. Phase two involved formulation of the GDG. The GDG consisted of 21 coloproctologists, three research fellows, a radiologist and a methodologist. Stakeholders were chosen for their clinical and academic involvement in the management of anal fistula as well as being representative of the geographical variation among the ESCP membership. Five patients were recruited from patient groups to review the draft guideline. These patients attended two virtual meetings to discuss the evidence and suggest amendments. In phase three, patient/population, intervention, comparison and outcomes questions were formulated by the GDG. The GDG ratified 250 questions and chose 45 for inclusion in the guideline. In phase four, critical and important outcomes were confirmed for inclusion. Important outcomes were pain and wound healing. Critical outcomes were fistula healing, fistula recurrence and incontinence. These outcomes formed part of the inclusion criteria for the literature search. In phase five, a literature search was performed of MEDLINE (Ovid), PubMed, Embase (Ovid) and the Cochrane Database of Systematic Reviews by eight teams of the GDG. Data were extracted and submitted for review by the GDG in a draft guideline. The most recent systematic reviews were prioritized for inclusion. Studies published since the most recent systematic review were included in our analysis by conducting a new meta-analysis using Review manager. In phase six, recommendations were formulated, using grading of recommendations, assessment, development, and evaluations, in three virtual meetings of the GDG. RESULTS: In seven sections covering the diagnostic and therapeutic management of perianal abscess and cryptoglandular anal fistula, there are 42 recommendations. CONCLUSION: This is an up-to-date international guideline on the management of cryptoglandular anal fistula using methodology prescribed by the AGREE enterprise.


Asunto(s)
Enfermedades del Ano , Fístula Rectal , Adulto , Humanos , Absceso , Revisiones Sistemáticas como Asunto , Fístula Rectal/diagnóstico , Fístula Rectal/cirugía , Cicatrización de Heridas , Resultado del Tratamiento
7.
Matern Child Health J ; 28(1): 5-10, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38142261

RESUMEN

INTRODUCTION: Adverse childhood experiences (ACEs) are common and have been associated with poor developmental outcomes. We aimed to investigate the relationship between early ACE exposure, subsequent diagnosis of developmental delay, and receipt of developmental delay services by young children. In addition, we aimed to assess the impact of health-promoting behaviors such as breastfeeding and daily reading on these relationships. METHODS: In this cross-sectional analysis of nationally-representative data from the 2017-2018 National Survey of Children's Health, we examined the relationship between ACEs, prior breastfeeding, daily reading, and developmental delay diagnosis among 7837 children aged 3-5 years, using multivariate logistic regression to adjust for family, personal, and sociodemographic characteristics. RESULTS: We found a dose-dependent relationship between ACEs and developmental delay diagnosis; compared to those without ACEs, developmental delay was more common among those with either one ACE (aOR = 2.03, 95% CI 1.17-3.52) or two or more ACEs (aOR = 2.34, 95% CI 1.25-4.37). Neither breastfeeding (exclusively breastfed for 6 months vs. never breastfed aOR = 0.70, 95% CI 0.33-1.46) nor daily reading (no reading versus daily reading aOR = 1.15, CI 0.57-2.33) were associated with incidence of developmental delay among study participants. There was no significant difference in receipt of services intended to meet developmental needs between children with and without ACEs. DISCUSSION: Children with very early ACE exposure are at increased risk for diagnosis of developmental delay. Early screening for ACEs and developmental delay may mitigate the early developmental manifestations of ACE exposure in vulnerable children.


As poor developmental outcomes are related to ACEs, children aged 3­5 years should be routinely screened for ACE exposure. Although breastfeeding and daily reading have multiple benefits to children, they do not adequately mitigate the developmental delays associated with ACE exposure.


Asunto(s)
Experiencias Adversas de la Infancia , Niño , Femenino , Humanos , Preescolar , Estudios Transversales , Lactancia Materna , Salud Infantil
8.
Int J Mol Sci ; 25(8)2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38674152

RESUMEN

The parasite Trichomonas vaginalis is the etiologic agent of trichomoniasis, the most common non-viral sexually transmitted disease worldwide. This infection often remains asymptomatic and is related to several health complications. The traditional treatment for trichomoniasis is the use of drugs of the 5-nitroimidazole family, such as metronidazole; however, scientific reports indicate an increasing number of drug-resistant strains. Benzimidazole derivatives could offer an alternative in the search for new anti-trichomonas drugs. In this sense, two attractive candidates are the compounds O2N-BZM7 and O2N-BZM9 (1H-benzimidazole derivatives), since, through in vitro tests, they have shown a higher trichomonacide activity. In this study, we determined the effect on the expression level of metabolic genes in T. vaginalis. The results show that genes involved in redox balance (NADHOX, G6PD::6PGL) are overexpressed, as well as the gene that participates in the first reaction of glycolysis (CK); on the other hand, structural genes such as ACT and TUB are decreased in expression in trophozoites treated with the compound O2N-BZM9, which would probably affect its morphology, motility and virulence. These results align with the trichomonacidal activity of the compounds, with benzimidazole O2N-BZM9 being the most potent, with an IC50 value of 4.8 µM. These results are promising for potential future therapeutic applications.


Asunto(s)
Bencimidazoles , Trichomonas vaginalis , Trichomonas vaginalis/efectos de los fármacos , Trichomonas vaginalis/genética , Trichomonas vaginalis/metabolismo , Bencimidazoles/farmacología , Proteínas Protozoarias/genética , Proteínas Protozoarias/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Antiprotozoarios/farmacología , Antitricomonas/farmacología
9.
Int J Mol Sci ; 25(9)2024 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-38732256

RESUMEN

Autosomal polycystic kidney disease (ADPKD) is the most common genetic form of kidney failure, reflecting unmet needs in management. Prescription of the only approved treatment (tolvaptan) is limited to persons with rapidly progressing ADPKD. Rapid progression may be diagnosed by assessing glomerular filtration rate (GFR) decline, usually estimated (eGFR) from equations based on serum creatinine (eGFRcr) or cystatin-C (eGFRcys). We have assessed the concordance between eGFR decline and identification of rapid progression (rapid eGFR loss), and measured GFR (mGFR) declines (rapid mGFR loss) using iohexol clearance in 140 adults with ADPKD with ≥3 mGFR and eGFRcr assessments, of which 97 also had eGFRcys assessments. The agreement between mGFR and eGFR decline was poor: mean concordance correlation coefficients (CCCs) between the method declines were low (0.661, range 0.628 to 0.713), and Bland and Altman limits of agreement between eGFR and mGFR declines were wide. CCC was lower for eGFRcys. From a practical point of view, creatinine-based formulas failed to detect rapid mGFR loss (-3 mL/min/y or faster) in around 37% of the cases. Moreover, formulas falsely indicated around 40% of the cases with moderate or stable decline as rapid progressors. The reliability of formulas in detecting real mGFR decline was lower in the non-rapid-progressors group with respect to that in rapid-progressor patients. The performance of eGFRcys and eGFRcr-cys equations was even worse. In conclusion, eGFR decline may misrepresent mGFR decline in ADPKD in a significant percentage of patients, potentially misclassifying them as progressors or non-progressors and impacting decisions of initiation of tolvaptan therapy.


Asunto(s)
Creatinina , Progresión de la Enfermedad , Tasa de Filtración Glomerular , Riñón Poliquístico Autosómico Dominante , Humanos , Femenino , Riñón Poliquístico Autosómico Dominante/tratamiento farmacológico , Riñón Poliquístico Autosómico Dominante/fisiopatología , Masculino , Persona de Mediana Edad , Adulto , Creatinina/sangre , Cistatina C/sangre , Anciano , Tolvaptán/uso terapéutico , Toma de Decisiones Clínicas
10.
Dis Colon Rectum ; 66(3): 383-391, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-35358109

RESUMEN

BACKGROUND: A barrier to the widespread adoption of watch-and-wait management for locally advanced rectal cancer is the inaccuracy and variability of identifying tumor response endoscopically in patients who have completed total neoadjuvant therapy (chemoradiotherapy and systemic chemotherapy). OBJECTIVE: This study aimed to develop a novel method of identifying the presence or absence of a tumor in endoscopic images using deep convolutional neural network-based automatic classification and to assess the accuracy of the method. DESIGN: In this prospective pilot study, endoscopic images obtained before, during, and after total neoadjuvant therapy were grouped on the basis of tumor presence. A convolutional neural network was modified for probabilistic classification of tumor versus no tumor and trained with an endoscopic image set. After training, a testing endoscopic imaging set was applied to the network. SETTINGS: The study was conducted at a comprehensive cancer center. PATIENTS: Images were analyzed from 109 patients who were diagnosed with locally advanced rectal cancer between December 2012 and July 2017 and who underwent total neoadjuvant therapy. MAIN OUTCOME MEASURES: The main outcomes were accuracy of identifying tumor presence or absence in endoscopic images measured as area under the receiver operating characteristic for the training and testing image sets. RESULTS: A total of 1392 images were included; 1099 images (468 of no tumor and 631 of tumor) were for training and 293 images (151 of no tumor and 142 of tumor) for testing. The area under the receiver operating characteristic for training and testing was 0.83. LIMITATIONS: The study had a limited number of images in each set and was conducted at a single institution. CONCLUSIONS: The convolutional neural network method is moderately accurate in distinguishing tumor from no tumor. Further research should focus on validating the convolutional neural network on a large image set. See Video Abstract at http://links.lww.com/DCR/B959 . MODELO BASADO EN APRENDIZAJE PROFUNDO PARA IDENTIFICAR TUMORES EN IMGENES ENDOSCPICAS DE PACIENTES CON CNCER DE RECTO LOCALMENTE AVANZADO TRATADOS CON TERAPIA NEOADYUVANTE TOTAL: ANTECEDENTES:Una barrera para la aceptación generalizada del tratamiento de Observar y Esperar para el cáncer de recto localmente avanzado, es la imprecisión y la variabilidad en la identificación de la respuesta tumoral endoscópica, en pacientes que completaron la terapia neoadyuvante total (quimiorradioterapia y quimioterapia sistémica).OBJETIVO:Desarrollar un método novedoso para identificar la presencia o ausencia de un tumor en imágenes endoscópicas utilizando una clasificación automática basada en redes neuronales convolucionales profundas y evaluar la precisión del método.DISEÑO:Las imágenes endoscópicas obtenidas antes, durante y después de la terapia neoadyuvante total se agruparon en base de la presencia del tumor. Se modificó una red neuronal convolucional para la clasificación probabilística de tumor versus no tumor y se entrenó con un conjunto de imágenes endoscópicas. Después del entrenamiento, se aplicó a la red un conjunto de imágenes endoscópicas de prueba.ENTORNO CLINICO:El estudio se realizó en un centro oncológico integral.PACIENTES:Analizamos imágenes de 109 pacientes que fueron diagnosticados de cáncer de recto localmente avanzado entre diciembre de 2012 y julio de 2017 y que se sometieron a terapia neoadyuvante total.PRINCIPALES MEDIDAS DE VALORACION:La precisión en la identificación de la presencia o ausencia de tumores en imágenes endoscópicas medidas como el área bajo la curva de funcionamiento del receptor para los conjuntos de imágenes de entrenamiento y prueba.RESULTADOS:Se incluyeron mil trescientas noventa y dos imágenes: 1099 (468 sin tumor y 631 con tumor) para entrenamiento y 293 (151 sin tumor y 142 con tumor) para prueba. El área bajo la curva operativa del receptor para entrenamiento y prueba fue de 0,83.LIMITACIONES:El estudio tuvo un número limitado de imágenes en cada conjunto y se realizó en una sola institución.CONCLUSIÓN:El método de la red neuronal convolucional es moderadamente preciso para distinguir el tumor de ningún tumor. La investigación adicional debería centrarse en validar la red neuronal convolucional en un conjunto de imágenes mayor. Consulte Video Resumen en http://links.lww.com/DCR/B959 . (Traducción -Dr. Fidel Ruiz Healy ).


Asunto(s)
Aprendizaje Profundo , Neoplasias Primarias Secundarias , Neoplasias del Recto , Humanos , Terapia Neoadyuvante/métodos , Estudios Retrospectivos , Estudios Prospectivos , Proyectos Piloto , Neoplasias del Recto/diagnóstico por imagen , Neoplasias del Recto/terapia , Neoplasias del Recto/patología
11.
Int J Mol Sci ; 24(24)2023 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-38139462

RESUMEN

Glioma cells exhibit genetic and metabolic alterations that affect the deregulation of several cellular signal transduction pathways, including those related to glucose metabolism. Moreover, oncogenic signaling pathways induce the expression of metabolic genes, increasing the metabolic enzyme activities and thus the critical biosynthetic pathways to generate nucleotides, amino acids, and fatty acids, which provide energy and metabolic intermediates that are essential to accomplish the biosynthetic needs of glioma cells. In this review, we aim to explore how dysregulated metabolic enzymes and their metabolites from primary metabolism pathways in glioblastoma (GBM) such as glycolysis and glutaminolysis modulate anabolic and catabolic metabolic pathways as well as pro-oncogenic signaling and contribute to the formation, survival, growth, and malignancy of glioma cells. Also, we discuss promising therapeutic strategies by targeting the key players in metabolic regulation. Therefore, the knowledge of metabolic reprogramming is necessary to fully understand the biology of malignant gliomas to improve patient survival significantly.


Asunto(s)
Glioblastoma , Glioma , Humanos , Glioblastoma/genética , Glioblastoma/metabolismo , Glutamina/metabolismo , Reprogramación Metabólica , Glucólisis/fisiología , Glioma/patología , Transducción de Señal , Apoptosis , Proliferación Celular/fisiología
12.
Int J Mol Sci ; 24(16)2023 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-37628871

RESUMEN

Glucose-6-phosphate dehydrogenase (G6PD) deficiency, affecting an estimated 500 million people worldwide, is a genetic disorder that causes human enzymopathies. Biochemical and genetic studies have identified several variants that produce different ranges of phenotypes; thus, depending on its severity, this enzymopathy is classified from the mildest (Class IV) to the most severe (Class I). Therefore, understanding the correlation between the mutation sites of G6PD and the resulting phenotype greatly enhances the current knowledge of enzymopathies' phenotypic and genotypic heterogeneity, which will assist both clinical diagnoses and personalized treatments for patients with G6PD deficiency. In this review, we analyzed and compared the structural and functional data from 21 characterized G6PD variants found in the Mexican population that we previously characterized. In order to contribute to the knowledge regarding the function and structure of the variants associated with G6PD deficiency, this review aimed to determine the molecular basis of G6PD and identify how these mutations could impact the structure, stability, and function of the enzyme and its relation with the clinical manifestations of this disease.


Asunto(s)
Deficiencia de Glucosafosfato Deshidrogenasa , Glucosafosfato Deshidrogenasa , Humanos , Glucosafosfato Deshidrogenasa/genética , Deficiencia de Glucosafosfato Deshidrogenasa/genética , Genotipo , Mutación , Fenotipo
13.
Int J Mol Sci ; 24(14)2023 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-37511272

RESUMEN

Giardiasis, which is caused by Giardia lamblia infection, is a relevant cause of morbidity and mortality worldwide. Because no vaccines are currently available to treat giardiasis, chemotherapeutic drugs are the main options for controlling infection. Evidence has shown that the nitro drug nitazoxanide (NTZ) is a commonly prescribed treatment for giardiasis; however, the mechanisms underlying NTZ's antigiardial activity are not well-understood. Herein, we identified the glucose-6-phosphate::6-phosphogluconate dehydrogenase (GlG6PD::6PGL) fused enzyme as a nitazoxanide target, as NTZ behaves as a GlG6PD::6PGL catalytic inhibitor. Furthermore, fluorescence assays suggest alterations in the stability of GlG6PD::6PGL protein, whereas the results indicate a loss of catalytic activity due to conformational and folding changes. Molecular docking and dynamic simulation studies suggest a model of NTZ binding on the active site of the G6PD domain and near the structural NADP+ binding site. The findings of this study provide a novel mechanistic basis and strategy for the antigiardial activity of the NTZ drug.


Asunto(s)
Giardia lamblia , Giardiasis , Humanos , Giardiasis/tratamiento farmacológico , Simulación del Acoplamiento Molecular , Tiazoles/farmacología , Tiazoles/uso terapéutico
14.
Molecules ; 28(22)2023 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-38005378

RESUMEN

A multi-objective optimization was performed using response surface methodology to obtain a high-value-added product, pectin enriched in polyphenols, from pomegranate peel. For this purpose, a green extraction technique that combines citric acid and ultrasound was carried out considering three variables: time, pH, and temperature. The extraction procedure was optimized using the Box-Behnken design, these being the most suitable conditions, with an extraction time of 34.16 min, a pH of 2.2, and a temperature of 89.87 °C. At this point, the pectin yield was 31.89%, with a total retained polyphenol content of 15.84 mg GAE/g pectin. In addition, the water activity, ash content, equivalent weight, methoxyl content, and degree of esterification were determined for the pectin obtained at the optimal point. This study demonstrates that polyphenol-enriched pectin can be obtained from pomegranate peel via an eco-friendly and efficient method, and that it presents similar properties to commercial pectin, preserving its quality and with potential use as an ingredient or food supplement with a high nutritional value. This work contributes to developing sustainable strategies to valorize pomegranate agro-industrial waste and produce high-value functional ingredients.


Asunto(s)
Pectinas , Granada (Fruta) , Pectinas/química , Polifenoles , Residuos Industriales , Temperatura
15.
Aten Primaria ; 55(7): 102630, 2023 07.
Artículo en Español | MEDLINE | ID: mdl-37119777

RESUMEN

This manuscript describes the factors that have led to the spread of low-value practices (LVP) and the main initiatives to reverse them. The paper highlights the strategies that have proven to be most useful over the years, from the alignment of clinical practice with "do not do" recommendations, to quaternary prevention and the risks associated with interventionism. Reversing LVP requires a planned process with a multifactorial approach engaging the different actors involved. It considers the barriers to de-implementation of low-value interventions and incorporates tools that facilitate adherence to "do not do" recommendations. Family doctor has an especially relevant role in LVP prevention, detection and de-implementation, due to their coordinating and integrating nature in the patients' healthcare, and because most of the citizens' healthcare demands are managed and resolved at the first level of care.

16.
Hum Genet ; 141(7): 1309-1325, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35190856

RESUMEN

Epigenetic diseases can be produced by a stable alteration, called an epimutation, in DNA methylation, in which epigenome alterations are directly involved in the underlying molecular mechanisms of the disease. This review focuses on the epigenetics of two inherited metabolic diseases, epi-cblC, an inherited metabolic disorder of cobalamin (vitamin B12) metabolism, and alpha-thalassemia type α-ZF, an inherited disorder of α2-globin synthesis, with a particular interest in the role of aberrant antisense transcription of flanking genes in the generation of epimutations in CpG islands of gene promoters. In both disorders, the epimutation is triggered by an aberrant antisense transcription through the promoter, which produces an H3K36me3 histone mark involved in the recruitment of DNA methyltransferases. It results from diverse genetic alterations. In alpha-thalassemia type α-ZF, a deletion removes HBA1 and HBQ1 genes and juxtaposes the antisense LUC7L gene to the HBA2 gene. In epi-cblC, the epimutation in the MMACHC promoter is produced by mutations in the antisense flanking gene PRDX1, which induces a prolonged antisense transcription through the MMACHC promoter. The presence of the epimutation in sperm, its transgenerational inheritance via the mutated PRDX1, and the high expression of PRDX1 in spermatogonia but its nearly undetectable transcription in spermatids and spermatocytes, suggest that the epimutation could be maintained during germline reprogramming and despite removal of aberrant transcription. The epivariation seen in the MMACHC promoter (0.95 × 10-3) is highly frequent compared to epivariations affecting other genes of the Online Catalog of Human Genes and Genetic Disorders in an epigenome-wide dataset of 23,116 individuals. This and the comparison of epigrams of two monozygotic twins suggest that the aberrant transcription could also be influenced by post-zygotic environmental exposures.


Asunto(s)
Enfermedades Metabólicas , Talasemia alfa , Metilación de ADN , Epigénesis Genética , Humanos , Masculino , Enfermedades Metabólicas/genética , Oxidorreductasas/genética , Semen , Talasemia alfa/genética
17.
Hum Genet ; 141(7): 1239-1251, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34652574

RESUMEN

Inherited disorders of cobalamin (cbl) metabolism (cblA-J) result in accumulation of methylmalonic acid (MMA) and/or homocystinuria (HCU). Clinical presentation includes ophthalmological manifestations related to retina, optic nerve and posterior visual alterations, mainly reported in cblC and sporadically in other cbl inborn errors.We searched MEDLINE EMBASE and Cochrane Library, and analyzed articles reporting ocular manifestations in cbl inborn errors. Out of 166 studies a total of 52 studies reporting 163 cbl and 24 mut cases were included. Ocular manifestations were found in all cbl defects except for cblB and cblD-MMA; cblC was the most frequent disorder affecting 137 (84.0%) patients. The c.271dupA was the most common pathogenic variant, accounting for 70/105 (66.7%) cases. One hundred and thirty-seven out of 154 (88.9%) patients presented with early-onset disease (0-12 months). Nystagmus and strabismus were observed in all groups with the exception of MMA patients while maculopathy and peripheral retinal degeneration were almost exclusively found in MMA-HCU patients. Optic nerve damage ranging from mild temporal disc pallor to complete atrophy was prevalent in MMA-HCU.and MMA groups. Nystagmus was frequent in early-onset patients. Retinal and macular degeneration worsened despite early treatment and stabilized systemic function in these patients. The functional prognosis remains poor with final visual acuity < 20/200 in 55.6% (25/45) of cases. In conclusion, the spectrum of eye disease in Cbl patients depends on metabolic severity and age of onset. The development of visual manifestations over time despite early metabolic treatment point out the need for specific innovative therapies.


Asunto(s)
Errores Innatos del Metabolismo de los Aminoácidos , Homocistinuria , Degeneración Macular , Degeneración Retiniana , Errores Innatos del Metabolismo de los Aminoácidos/complicaciones , Errores Innatos del Metabolismo de los Aminoácidos/genética , Errores Innatos del Metabolismo de los Aminoácidos/metabolismo , Homocistinuria/complicaciones , Homocistinuria/genética , Humanos , Ácido Metilmalónico , Mutación , Retina/metabolismo , Vitamina B 12/metabolismo
18.
Ann Surg Oncol ; 29(2): 1172-1179, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34601641

RESUMEN

BACKGROUND AND OBJECTIVES: Watch-and-wait is variably adopted by surgeons and the impact of this on outcomes is unknown. We compared the disease-free survival and organ preservation rates of locally advanced rectal cancer patients treated by expert colorectal surgeons at a comprehensive cancer center. METHODS: This study included retrospective data on patients diagnosed with stage II/III rectal adenocarcinoma from January 2013 to June 2017 who initiated neoadjuvant therapy (either with chemoradiation, chemotherapy, or a combination of both) and were treated by an expert colorectal surgeon. RESULTS: Overall, 444 locally advanced rectal cancer patients managed by five surgeons were included. Tumor distance from the anal verge, type of neoadjuvant therapy, and organ preservation rates varied by treating surgeon. There was no difference in disease-free survival after stratifying by the treating surgeon (p = 0.2). On multivariable analysis, neither the type of neoadjuvant therapy nor the treating surgeon was associated with disease-free survival. CONCLUSIONS: While neoadjuvant therapy type and organ preservation rates varied among surgeons, there were no meaningful differences in disease-free survival. These data suggest that among expert colorectal surgeons, differing thresholds for selecting patients for watch-and-wait do not affect survival.


Asunto(s)
Neoplasias del Recto , Cirujanos , Quimioradioterapia , Humanos , Terapia Neoadyuvante , Recurrencia Local de Neoplasia , Estadificación de Neoplasias , Preservación de Órganos , Neoplasias del Recto/patología , Neoplasias del Recto/terapia , Estudios Retrospectivos , Resultado del Tratamiento , Espera Vigilante
19.
Allergy ; 77(6): 1827-1834, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-34687232

RESUMEN

BACKGROUND: Nonimmediate (delayed)-allergic reactions to penicillins are common and some of them can be life-threatening. The genetic factors influencing these reactions are unknown/poorly known/poorly understood. We assessed the genetic predictors of a delayed penicillin allergy that cover the HLA loci. METHODS: Using next-generation sequencing (NGS), we genotyped the MHC region in 24 patients with delayed hypersensitivity compared with 20 patients with documented immediate hypersensitivity to penicillins recruited in Italy. Subsequently, we analyzed in silico Illumina Immunochip genotyping data that covered the HLA loci in 98 Spanish patients with delayed hypersensitivity and 315 with immediate hypersensitivity compared to 1,308 controls. RESULTS: The two alleles DRB3*02:02:01:02 and DRB3*02:02:01:01 were reported in twenty cases with delayed reactions (83%) and ten cases with immediate reactions (50%), but not in the Allele Frequency Net Database. Bearing at least one of the two alleles increased the risk of delayed reactions compared to immediate reactions, with an OR of 8.88 (95% CI, 3.37-23.32; p < .0001). The haplotype (ACAA) from rs9268835, rs6923504, rs6903608, and rs9268838 genetic variants of the HLA-DRB3 genomic region was significantly associated with an increased risk of delayed hypersensitivity to penicillins (OR, 1.7; 95% CI: 1.06-1.92; p = .001), but not immediate hypersensitivity. CONCLUSION: We showed that the HLA-DRB3 locus is strongly associated with an increased risk of delayed penicillin hypersensitivity, at least in Southwestern Europe. The determination of HLA-DRB3*02:02 alleles in the risk management of severe delayed hypersensitivity to penicillins should be evaluated further in larger population samples of different origins.


Asunto(s)
Hipersensibilidad a las Drogas , Hipersensibilidad Tardía , Hipersensibilidad Inmediata , Alelos , Hipersensibilidad a las Drogas/epidemiología , Genotipo , Cadenas HLA-DRB3/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Hipersensibilidad Tardía/inducido químicamente , Hipersensibilidad Tardía/genética , Hipersensibilidad Inmediata/complicaciones , Penicilinas/efectos adversos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA