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1.
Annu Rev Biochem ; 82: 531-50, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23746262

RESUMO

Methylamine dehydrogenase (MADH) catalyzes the oxidative deamination of methylamine to formaldehyde and ammonia. Tryptophan tryptophylquinone (TTQ) is the protein-derived cofactor of MADH required for this catalytic activity. TTQ is biosynthesized through the posttranslational modification of two tryptophan residues within MADH, during which the indole rings of two tryptophan side chains are cross-linked and two oxygen atoms are inserted into one of the indole rings. MauG is a c-type diheme enzyme that catalyzes the final three reactions in TTQ formation. In total, this is a six-electron oxidation process requiring three cycles of MauG-dependent two-electron oxidation events using either H2O2 or O2. The MauG redox form responsible for the catalytic activity is an unprecedented bis-Fe(IV) species. The amino acids of MADH that are modified are ≈ 40 Å from the site where MauG binds oxygen, and the reaction proceeds by a hole hopping electron transfer mechanism. This review addresses these highly unusual aspects of the long-range catalytic reaction mediated by MauG.


Assuntos
Heme/metabolismo , Indolquinonas/biossíntese , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/metabolismo , Paracoccus denitrificans/enzimologia , Processamento de Proteína Pós-Traducional/fisiologia , Triptofano/análogos & derivados , Triptofano/metabolismo , Catálise , Transporte de Elétrons , Oxirredução , Paracoccus denitrificans/genética , Paracoccus denitrificans/metabolismo , Triptofano/biossíntese
2.
Nat Immunol ; 17(9): 1075-83, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27400149

RESUMO

Adhesion and migration of T cells are controlled by chemokines and by adhesion molecules, especially integrins, and have critical roles in the normal physiological function of T lymphocytes. Using an RNA-mediated interference screen, we identified the WNK1 kinase as a regulator of both integrin-mediated adhesion and T cell migration. We found that WNK1 is a negative regulator of integrin-mediated adhesion, whereas it acts as a positive regulator of migration via the kinases OXSR1 and STK39 and the ion co-transporter SLC12A2. WNK1-deficient T cells home less efficiently to lymphoid organs and migrate more slowly through them. Our results reveal that a pathway previously known only to regulate salt homeostasis in the kidney functions to balance T cell adhesion and migration.


Assuntos
Adesão Celular/genética , Movimento Celular/genética , Antígenos de Histocompatibilidade Menor/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Receptores de Retorno de Linfócitos/metabolismo , Linfócitos T/fisiologia , Animais , Células Cultivadas , Homeostase , Transporte de Íons , Rim/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Antígenos de Histocompatibilidade Menor/genética , Proteínas Serina-Treonina Quinases/genética , Interferência de RNA , Receptores de Retorno de Linfócitos/genética , Membro 2 da Família 12 de Carreador de Soluto/metabolismo , Proteína Quinase 1 Deficiente de Lisina WNK
3.
Development ; 150(8)2023 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-37102702

RESUMO

Down syndrome (DS), trisomy of human chromosome 21 (Hsa21), occurs in 1 in 800 live births and is the most common human aneuploidy. DS results in multiple phenotypes, including craniofacial dysmorphology, which is characterised by midfacial hypoplasia, brachycephaly and micrognathia. The genetic and developmental causes of this are poorly understood. Using morphometric analysis of the Dp1Tyb mouse model of DS and an associated mouse genetic mapping panel, we demonstrate that four Hsa21-orthologous regions of mouse chromosome 16 contain dosage-sensitive genes that cause the DS craniofacial phenotype, and identify one of these causative genes as Dyrk1a. We show that the earliest and most severe defects in Dp1Tyb skulls are in bones of neural crest (NC) origin, and that mineralisation of the Dp1Tyb skull base synchondroses is aberrant. Furthermore, we show that increased dosage of Dyrk1a results in decreased NC cell proliferation and a decrease in size and cellularity of the NC-derived frontal bone primordia. Thus, DS craniofacial dysmorphology is caused by an increased dosage of Dyrk1a and at least three other genes.


Assuntos
Síndrome de Down , Camundongos , Humanos , Animais , Síndrome de Down/genética , Crânio , Mapeamento Cromossômico , Fenótipo , Modelos Animais de Doenças
4.
Am J Hum Genet ; 109(10): 1828-1849, 2022 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-36084634

RESUMO

Orofaciodigital syndrome (OFD) is a genetically heterogeneous ciliopathy characterized by anomalies of the oral cavity, face, and digits. We describe individuals with OFD from three unrelated families having bi-allelic loss-of-function variants in SCNM1 as the cause of their condition. SCNM1 encodes a protein recently shown to be a component of the human minor spliceosome. However, so far the effect of loss of SCNM1 function on human cells had not been assessed. Using a comparative transcriptome analysis between fibroblasts derived from an OFD-affected individual harboring SCNM1 mutations and control fibroblasts, we identified a set of genes with defective minor intron (U12) processing in the fibroblasts of the affected subject. These results were reproduced in SCNM1 knockout hTERT RPE-1 (RPE-1) cells engineered by CRISPR-Cas9-mediated editing and in SCNM1 siRNA-treated RPE-1 cultures. Notably, expression of TMEM107 and FAM92A encoding primary cilia and basal body proteins, respectively, and that of DERL2, ZC3H8, and C17orf75, were severely reduced in SCNM1-deficient cells. Primary fibroblasts containing SCNM1 mutations, as well as SCNM1 knockout and SCNM1 knockdown RPE-1 cells, were also found with abnormally elongated cilia. Conversely, cilia length and expression of SCNM1-regulated genes were restored in SCNM1-deficient fibroblasts following reintroduction of SCNM1 via retroviral delivery. Additionally, functional analysis in SCNM1-retrotransduced fibroblasts showed that SCNM1 is a positive mediator of Hedgehog (Hh) signaling. Our findings demonstrate that defective U12 intron splicing can lead to a typical ciliopathy such as OFD and reveal that primary cilia length and Hh signaling are regulated by the minor spliceosome through SCNM1 activity.


Assuntos
Ciliopatias , Síndromes Orofaciodigitais , Cílios/genética , Cílios/metabolismo , Ciliopatias/genética , Proteínas Hedgehog/metabolismo , Humanos , Íntrons/genética , Mutação/genética , Síndromes Orofaciodigitais/genética , Splicing de RNA/genética , Fatores de Processamento de RNA/metabolismo , RNA Interferente Pequeno/metabolismo , Spliceossomos/genética , Spliceossomos/metabolismo
5.
J Neurosci ; 43(9): 1492-1508, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36653191

RESUMO

NG2 is a structurally unique transmembrane chondroitin sulfate proteoglycan (CSPG). Its role in damaged spinal cord is dual. NG2 is considered one of key inhibitory factors restricting axonal growth following spinal injury. Additionally, we have recently detected its novel function as a blocker of axonal conduction. Some studies, however, indicate the importance of NG2 presence in the formation of synaptic contacts. We hypothesized that the optimal treatment would be neutralization of inhibitory functions of NG2 without its physical removal. Acute intraspinal injections of anti-NG2 monoclonal antibodies reportedly prevented an acute block of axonal conduction by exogenous NG2. For prolonged delivery of NG2 function neutralizing antibody, we have developed a novel gene therapy: adeno-associated vector (AAV) construct expressing recombinant single-chain variable fragment anti-NG2 antibody (AAV-NG2Ab). We examined effects of AAV-NG2Ab alone or in combination with neurotrophin NT-3 in adult female rats with thoracic T10 contusion injuries. A battery of behavioral tests was used to evaluate locomotor function. In vivo single-cell electrophysiology was used to evaluate synaptic transmission. Lower urinary tract function was assessed during the survival period using metabolic chambers. Terminal cystometry, with acquisition of external urethral sphincter activity and bladder pressure, was used to evaluate bladder function. Both the AAV-NG2Ab and AAV-NG2Ab combined with AAV-NT3 treatment groups demonstrated significant improvements in transmission, locomotion, and bladder function compared with the control (AAV-GFP) group. These functional improvements associated with improved remyelination and plasticity of 5-HT fibers. The best results were observed in the group that received combinational AAV-NG2Ab+AAV-NT3 treatment.SIGNIFICANCE STATEMENT We recently demonstrated beneficial, but transient, effects of neutralization of the NG2 proteoglycan using monoclonal antibodies delivered intrathecally via osmotic mini-pumps after spinal cord injury. Currently, we have developed a novel gene therapy tool for prolonged and clinically relevant delivery of a recombinant single-chain variable fragment anti-NG2 antibody: AAV-rh10 serotype expressing scFv-NG2 (AAV-NG2Ab). Here, we examined effects of AAV-NG2Ab combined with transgene delivery of Neurotrophin-3 (AAV-NT3) in adult rats with thoracic contusion injuries. The AAV-NG2Ab and AAV-NG2Ab+AAV-NT3 treatment groups demonstrated significant improvements of locomotor function and lower urinary tract function. Beneficial effects of this novel gene therapy on locomotion and bladder function associated with improved transmission to motoneurons and plasticity of axons in damaged spinal cord.


Assuntos
Contusões , Anticorpos de Cadeia Única , Traumatismos da Medula Espinal , Sistema Urinário , Animais , Feminino , Ratos , Contusões/terapia , Locomoção , Fatores de Crescimento Neural , Recuperação de Função Fisiológica/genética , Medula Espinal , Transmissão Sináptica , Neurotrofina 3
6.
Pflugers Arch ; 476(8): 1209-1219, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38829391

RESUMO

The intestinal epithelium is covered by mucus that protects the tissue from the luminal content. Studies have shown that anion secretion via the cystic fibrosis conductance regulator (Cftr) regulates mucus formation in the small intestine. However, mechanisms regulating mucus formation in the colon are less understood. The aim of this study was to explore the role of anion transport in the regulation of mucus formation during steady state and in response to carbamylcholine (CCh) and prostaglandin E2 (PGE2). The broad-spectrum anion transport inhibitor 4,4'-diisothiocyanatostilbene-2,2'-disulfonate (DIDS), CftrdF508 (CF) mice, and the slc26a3 inhibitor SLC26A3-IN-2 were used to inhibit anion transport. In the distal colon, steady-state mucus expansion was reduced by SLC26A3-IN-2 and normal in CF mice. PGE2 stimulated mucus expansion without de novo mucus release in wild type (WT) and CF colon via slc26a3 sensitive mechanisms, while CCh induced de novo mucus secretion in WT but not in CF colon. However, when added simultaneously, CCh and PGE2 stimulated de novo mucus secretion in the CF colon via DIDS-sensitive pathways. A similar response was observed in CF ileum that responded to CCh and PGE2 with DIDS-sensitive de novo mucus secretion. In conclusion, this study suggests that slc26a3 regulates colonic mucus expansion, while Cftr regulates CCh-induced de novo mucus secretion from ileal and distal colon crypts. Furthermore, these findings demonstrate that in the absence of a functional Cftr channel, parallel stimulation with CCh and PGE2 activates additional anion transport processes that help release mucus from intestinal goblet cells.


Assuntos
Carbacol , Colo , Regulador de Condutância Transmembrana em Fibrose Cística , Dinoprostona , Muco , Transportadores de Sulfato , Animais , Dinoprostona/metabolismo , Dinoprostona/farmacologia , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Transportadores de Sulfato/metabolismo , Transportadores de Sulfato/genética , Camundongos , Colo/metabolismo , Colo/efeitos dos fármacos , Muco/metabolismo , Muco/efeitos dos fármacos , Carbacol/farmacologia , Camundongos Endogâmicos C57BL , Ácido 4,4'-Di-Isotiocianoestilbeno-2,2'-Dissulfônico/farmacologia , Antiporters/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Masculino
7.
J Neurochem ; 168(9): 2736-2750, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38814273

RESUMO

The reliability of plasma biomarkers of Alzheimer's disease (AD) can be compromised by protease-induced degradation. This can limit the feasibility of conducting plasma biomarker studies in environments that lack the capacity for immediate processing and appropriate storage of blood samples. We hypothesized that blood collection tube supplementation with protease inhibitors can improve the stability of plasma biomarkers at room temperatures (RT). In this study, we conducted a comparative analysis of blood biomarker stability in traditional ethylenediaminetetraacetic acid (EDTA) tubes versus BD™ P100 collection tubes, the latter being coated with a protease inhibitor cocktail. The stability of six plasma AD biomarkers was evaluated over time under RT conditions. We evaluated three experimental approaches. In Approach 1, pooled plasma samples underwent storage at RT for up to 96 h. In Approach 2, plasma samples isolated upfront from whole blood collected into EDTA or P100 tubes were stored at RT for 0 h or 24 h before biomarker measurements. In Approach 3, whole blood samples were collected into paired EDTA and P100 tubes, followed by storage at RT for 0 h or 24 h before isolating the plasma for analyses. Biomarkers were measured with Single Molecule Array (Simoa) and immunoprecipitation-mass spectrometry (IP-MS) assays. Both the IP-MS and Simoa methods revealed that the use of P100 tubes significantly improves the stability of Aß42 and Aß40 across all approaches. However, the Aß42/Aß40 ratio levels were significantly stabilized only in the IP-MS assay in Approach 3. No significant differences were observed in the levels of plasma p-tau181, GFAP, and NfL for samples collected using either tube type in any of the approaches. Supplementation of blood collection tubes with protease inhibitors could reduce the protease-induced degradation of plasma Aß42 and Aß40, and the Aß42/40 ratio for the IP-MS assay. These findings have crucial implications for preanalytical procedures, particularly in resource-limited settings.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Biomarcadores , Coleta de Amostras Sanguíneas , Inibidores de Proteases , Doença de Alzheimer/sangue , Humanos , Coleta de Amostras Sanguíneas/métodos , Biomarcadores/sangue , Inibidores de Proteases/farmacologia , Masculino , Idoso , Feminino , Peptídeos beta-Amiloides/sangue , Idoso de 80 Anos ou mais , Ácido Edético/farmacologia , Proteínas tau/sangue , Fragmentos de Peptídeos/sangue
8.
Development ; 148(18)2021 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-33712441

RESUMO

Characterising phenotypes often requires quantification of anatomical shape. Quantitative shape comparison (morphometrics) traditionally uses manually located landmarks and is limited by landmark number and operator accuracy. Here, we apply a landmark-free method to characterise the craniofacial skeletal phenotype of the Dp1Tyb mouse model of Down syndrome and a population of the Diversity Outbred (DO) mouse model, comparing it with a landmark-based approach. We identified cranial dysmorphologies in Dp1Tyb mice, especially smaller size and brachycephaly (front-back shortening), homologous to the human phenotype. Shape variation in the DO mice was partly attributable to allometry (size-dependent shape variation) and sexual dimorphism. The landmark-free method performed as well as, or better than, the landmark-based method but was less labour-intensive, required less user training and, uniquely, enabled fine mapping of local differences as planar expansion or shrinkage. Its higher resolution pinpointed reductions in interior mid-snout structures and occipital bones in both the models that were not otherwise apparent. We propose that this landmark-free pipeline could make morphometrics widely accessible beyond its traditional niches in zoology and palaeontology, especially in characterising developmental mutant phenotypes.


Assuntos
Pontos de Referência Anatômicos/fisiopatologia , Síndrome de Down/fisiopatologia , Imageamento Tridimensional/métodos , Animais , Pesos e Medidas Corporais/métodos , Modelos Animais de Doenças , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fenótipo , Caracteres Sexuais , Crânio/fisiopatologia
9.
PLoS Pathog ; 18(9): e1010811, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36095012

RESUMO

SARS-CoV-2 non-structural protein Nsp14 is a highly conserved enzyme necessary for viral replication. Nsp14 forms a stable complex with non-structural protein Nsp10 and exhibits exoribonuclease and N7-methyltransferase activities. Protein-interactome studies identified human sirtuin 5 (SIRT5) as a putative binding partner of Nsp14. SIRT5 is an NAD-dependent protein deacylase critical for cellular metabolism that removes succinyl and malonyl groups from lysine residues. Here we investigated the nature of this interaction and the role of SIRT5 during SARS-CoV-2 infection. We showed that SIRT5 interacts with Nsp14, but not with Nsp10, suggesting that SIRT5 and Nsp10 are parts of separate complexes. We found that SIRT5 catalytic domain is necessary for the interaction with Nsp14, but that Nsp14 does not appear to be directly deacylated by SIRT5. Furthermore, knock-out of SIRT5 or treatment with specific SIRT5 inhibitors reduced SARS-CoV-2 viral levels in cell-culture experiments. SIRT5 knock-out cells expressed higher basal levels of innate immunity markers and mounted a stronger antiviral response, independently of the Mitochondrial Antiviral Signaling Protein MAVS. Our results indicate that SIRT5 is a proviral factor necessary for efficient viral replication, which opens novel avenues for therapeutic interventions.


Assuntos
COVID-19 , Sirtuínas , Antivirais , Exorribonucleases/metabolismo , Humanos , Lisina , Metiltransferases/metabolismo , NAD , Provírus , RNA Viral/metabolismo , SARS-CoV-2 , Sirtuínas/genética , Proteínas não Estruturais Virais/metabolismo
11.
Ophthalmology ; 131(9): 1064-1075, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38452874

RESUMO

PURPOSE: Analyze the influence of risk factors at presentation in the long-term immunosuppressive therapy (IMT) outcomes of ocular mucous membrane pemphigoid (OMMP). DESIGN: Retrospective multicenter study. PARTICIPANTS: Patients with OMMP seen at the Duke Eye Center, Tecnologico de Monterrey, and Hospital Clinic of Barcelona from 1990 to 2022. METHODS: Data at presentation on demographics, direct immunofluorescence, ocular findings, sites of extraocular manifestations (EOMs), and previous treatments in patients with a clinical or laboratory diagnosis of OMMP, were analyzed with multivariable analysis and Kaplan-Meier plots to identify factors associated with adverse outcomes. MAIN OUTCOME MEASURES: (1) Inflammatory control (no conjunctival inflammation in both eyes at 3 months on IMT); (2) relapse (new-onset inflammation after absolute control in either eye); (3) progression (≥ 1 cicatrizing stage progression in either eye); and (4) vision loss (≥ 2 Snellen lines). RESULTS: A total of 117 patients (234 eyes), 61% (71/117) of whom were women, with a mean age of 66.6 (SD: 12.4) years (range: 37-97 years) and median follow-up of 34 months (interquartile range: 16-66 months; range: 3-265 months), were enrolled. Inflammatory control was achieved in 57% of patients (67/117), with high-risk EOM (HR-EOM), including esophageal, nasopharyngeal, and/or genital involvement (adjusted odds ratio [aOR]: 12.51; 95% confidence interval [CI]: 2.61-59.99; P = 0.002) and corneal scarring (aOR: 3.06; 95% CI, 1.15-8.14; P = 0.025), as significant risk factors for persistent inflammation. Disease relapse, progression, and vision loss occurred in 20% of patients (23/117), 12% of patients (14/117), and 27% of patients (32/117), respectively. Baseline corneal scarring was a risk factor for relapse (adjusted hazard ratio: 4.14; 95% CI: 1.61-10.62; P = 0.003), progression (aOR: 11.46; 95% CI: 1.78-73.75; P = 0.010), and vision loss (aOR: 3.51; 95% CI: 1.35-9.10; P = 0.010). HR-EOM was associated with stage progression (aOR, 34.57; 95% CI, 6.57-181.89; P<0.001) and vision loss (aOR, 8.42; 95% CI, 2.50-28.42; P = 0.001). No significant differences were found between IMT regimes and relapse (P = 0.169). CONCLUSIONS: Ocular mucous membrane pemphigoid presenting with HR-EOMs and corneal scarring has an increased risk of stage progression and vision loss. Corneal scarring and severe inflammation at baseline were associated with an increased risk of relapse. A disease progression staging system incorporating both the HR-EOMs and corneal involvement is required to predict the visual outcome of OMMP better. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.


Assuntos
Imunossupressores , Penfigoide Mucomembranoso Benigno , Humanos , Penfigoide Mucomembranoso Benigno/tratamento farmacológico , Penfigoide Mucomembranoso Benigno/diagnóstico , Penfigoide Mucomembranoso Benigno/fisiopatologia , Feminino , Masculino , Idoso , Estudos Retrospectivos , Fatores de Risco , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Adulto , Imunossupressores/uso terapêutico , Resultado do Tratamento , Acuidade Visual/fisiologia , Progressão da Doença , Seguimentos , Recidiva , Glucocorticoides/uso terapêutico
12.
Clin Genet ; 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39191491

RESUMO

Non-immune hydrops fetalis (NIHF) is a rare entity characterized by excessive accumulation of fluid within the fetal extravascular compartments and body cavities. Here we present two intrauterine fetal demises with NIHF presenting with oligohydramnios, cystic hygroma, pleural effusion, and generalized hydrops with predominance of subcutaneous edema. The fetuses also presented with ascites, severe and precocious IUGR and skeletal anomalies. Whole exome sequencing was applied in order to screen for a possible genetic cause. The results identified biallelic variants in MYBBP1A in both fetuses. A previous report described another case with a similar phenotype having compound heterozygous variants in the same gene. The protein encoded by MYBBP1A is involved in several cellular processes including the synthesis of ribosomal DNA, the response to nucleolar stress, and tumor suppression. Our functional protein analysis through immunohistochemistry indicates that MYBBP1A is a gene expressed during fetal stages. Altogether, we concluded that MYBBP1A is associated with the development of hydrops fetalis. More cases and further studies are necessary to understand the role of this gene and the mechanism associated with NIHF.

13.
Phys Rev Lett ; 133(12): 126505, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39373408

RESUMO

Two-dimensional coherent terahertz spectroscopy (2DCS) emerges as a valuable tool to probe the nature, couplings, and lifetimes of excitations in quantum materials. It thus promises to identify unique signatures of spin liquid states in quantum magnets by directly probing properties of their exotic fractionalized excitations. Here, we calculate the second-order 2DCS of the Kitaev honeycomb model and demonstrate that distinct spin liquid fingerprints appear already in this lowest-order nonlinear response χ_{yzx}^{(2)}(ω_{1},ω_{2}) when using crossed light polarizations. We further relate the off-diagonal 2DCS peaks to the localized nature of the matter Majorana excitations trapped by Z_{2} flux excitations and show that 2DCS thus directly probes the inverse participation ratio of Majorana wave functions. By providing experimentally observable features of spin liquid states in the 2D spectrum, our Letter can guide future 2DCS experiments on Kitaev magnets.

14.
J Nutr ; 154(3): 804-814, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38253225

RESUMO

In wealthy countries, the protein intake of adults is usually considered to be adequate, and considerations of protein quality are often deemed irrelevant. The objective was to examine dietary protein intakes of adults in developed countries in the context of dietary protein quality. An analysis of NHANES population data on actual protein intakes in the United States (a developed country) demonstrated that for a dietary Digestible Indispensable Amino Acid Score (DIAAS) of 100%, 11% of the adult (19-50 y) population had habitual protein intakes below the Estimated Average Requirement (EAR) and 22% below the Recommended Dietary Allowance. The percentage of the population with utilizable protein intakes potentially falling below the EAR increased as the assumed DIAAS declined. Analysis of the NHANES data and several other datasets also indicated that total protein intakes can be limiting or close to limiting for the elderly and some vegetarians and vegans. Here, lower dietary protein quality can potentially lead to inadequate utilizable protein intakes. For many people in specific physiological states (e.g., weight loss, endurance sports, resistance exercise) attempting to meet higher dietary protein targets often with accompanying lowered energy intakes, low dietary protein quality can lead to protein calories expressed as a proportion of total calories, falling outside what may be acceptable limits (maximum of 30% protein calories from total calories). In general, individuals within the adult population may be susceptible to macronutrient imbalance (whenever total protein intakes are high, daily energy intakes low) and for diets with lower protein quality (DIAAS <100%). Our analysis shows that dietary protein quality is relevant in mid- to high-income countries.


Assuntos
Dieta , Ingestão de Energia , Humanos , Adulto , Estados Unidos , Idoso , Países Desenvolvidos , Inquéritos Nutricionais , Proteínas Alimentares/metabolismo , Dieta com Restrição de Proteínas
15.
J Nutr ; 154(9): 2732-2742, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39025331

RESUMO

BACKGROUND: Current guidelines for the treatment of obesity recommend dietary restriction to create a caloric deficit, and caloric reductions of 16% to 68% have been achieved in adults with overweight or obesity engaging in intentional weight loss programs. OBJECTIVES: This study models the impact of simulated caloric reduction on nutrient adequacy among U.S. adults ≥19 y with overweight or obesity using National Health and Nutrition Examination Survey data (2015-2018). METHODS: Four levels of caloric reduction (20%, 30%, 40%, and 50%) were modeled by prorating daily calorie intake such that usual intakes of 14 nutrients were reduced proportional to caloric reduction. The percentages below the estimated average requirement (EAR) or above the adequate intake (AI) were estimated at each level of caloric reduction, with and without dietary supplement use. Differences across percentages of simulated caloric reductions were determined using nonoverlapping confidence intervals of the means (97.5th percentile confidence intervals were used to approximate P < 0.05). RESULTS: There were significant differences (P < 0.05) in percentages below the EAR (above the AI) between sequential levels of simulated caloric reduction for most of the nutrients analyzed (protein, vitamins A, B-6, folate, and C, calcium, iron, magnesium, potassium, and zinc). For example, after a simulated 30% caloric reduction, 25%-40% of the population had intakes below the EAR for protein, vitamin B-6, and zinc, and 75%-91% of the population had intakes below the EAR for vitamin A, calcium, and magnesium (vs. 4%-18% and 45%-56%, respectively, without caloric reduction). With the inclusion of dietary supplements, percentages below the EAR for all nutrients (except protein) were lower than those for food alone. CONCLUSIONS: Caloric reduction may exacerbate nutrient inadequacies among adults with overweight or obesity. Inclusion of nutrient-dense foods, fortified foods, specially formulated products, and/or dietary supplements should be considered for those on calorie-restricted diets for long-term weight loss.


Assuntos
Restrição Calórica , Inquéritos Nutricionais , Obesidade , Sobrepeso , Humanos , Adulto , Obesidade/dietoterapia , Sobrepeso/dietoterapia , Estados Unidos , Masculino , Feminino , Ingestão de Energia , Pessoa de Meia-Idade , Nutrientes , Adulto Jovem , Estado Nutricional
16.
Mol Psychiatry ; 28(3): 1248-1255, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36476732

RESUMO

Attention-deficit/hyperactivity disorder (ADHD) persists in older age and is postulated as a risk factor for cognitive impairment and Alzheimer's Disease (AD). However, these findings rely primarily on electronic health records and can present biased estimates of disease prevalence. An obstacle to investigating age-related cognitive decline in ADHD is the absence of large-scale studies following patients with ADHD into older age. Alternatively, this study aimed to determine whether genetic liability for ADHD, as measured by a well-validated ADHD polygenic risk score (ADHD-PRS), is associated with cognitive decline and the development of AD pathophysiology in cognitively unimpaired (CU) older adults. We calculated a weighted ADHD-PRS in 212 CU individuals without a clinical diagnosis of ADHD (55-90 years). These individuals had baseline amyloid-ß (Aß) positron emission tomography, longitudinal cerebrospinal fluid (CSF) phosphorylated tau at threonine 181 (p-tau181), magnetic resonance imaging, and cognitive assessments for up to 6 years. Linear mixed-effects models were used to test the association of ADHD-PRS with cognition and AD biomarkers. Higher ADHD-PRS was associated with greater cognitive decline over 6 years. The combined effect between high ADHD-PRS and brain Aß deposition on cognitive deterioration was more significant than each individually. Additionally, higher ADHD-PRS was associated with increased CSF p-tau181 levels and frontoparietal atrophy in CU Aß-positive individuals. Our results suggest that genetic liability for ADHD is associated with cognitive deterioration and the development of AD pathophysiology. Findings were mostly observed in Aß-positive individuals, suggesting that the genetic liability for ADHD increases susceptibility to the harmful effects of Aß pathology.


Assuntos
Doença de Alzheimer , Transtorno do Deficit de Atenção com Hiperatividade , Disfunção Cognitiva , Humanos , Idoso , Doença de Alzheimer/genética , Peptídeos beta-Amiloides , Tomografia por Emissão de Pósitrons/métodos , Fatores de Risco , Proteínas tau , Biomarcadores/líquido cefalorraquidiano
17.
Ann Bot ; 133(7): 1025-1040, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38502708

RESUMO

BACKGROUND AND AIMS: Maerl-associated communities have received considerable attention due to their uniqueness, biodiversity and functional importance. Although the impacts of human activities are well documented for maerl-associated macrofauna, the spatio-temporal variations of macroalgae have comparatively been neglected, and the drivers that influence their dynamics are poorly known. We investigate the links between maerl-associated macroalgal communities, anthropogenic pressures and environmental conditions, and hypothesize that sites under human pressure would exhibit different dynamics when compared to reference sites. METHODS: To better understand community variation through space and time, four subtidal maerl beds under different pressures were consistently monitored over one year in the bay of Brest, Brittany, France. Both macroalgae community monitoring and environmental data were acquired through field sampling and available models. KEY RESULTS: Higher macroalgal biomass was observed within eutrophic sites, especially in summer (more than ten times higher than in the Unimpacted site), caused by free-living forms of opportunistic red macroalgae. The Dredged site also exhibited distinct macroalgal communities during summer from the Unimpacted site. Nutrient concentrations and seasonality proved to be key factors affecting the macroalgal community composition, although dredging and its effects on granulometry also had a strong influence. Over the long term, fewer than half of the species identified during historical surveys were found, indicating major temporal changes. CONCLUSIONS: Human pressures have strong impacts on maerl-associated macroalgal communities. Nutrient concentrations and dredging pressure appear as the main anthropogenic factors shaping maerl-associated macroalgal communities. Additionally, our results suggest historical changes in maerl-associated macroalgal communities over 25 years in response to changes in local human pressure management. This study suggests that maerl-associated macroalgal communities could be used as indicators of anthropogenically driven changes in this habitat.


Assuntos
Alga Marinha , Alga Marinha/fisiologia , França , Humanos , Ecossistema , Estações do Ano , Biodiversidade , Efeitos Antropogênicos , Biomassa , Dinâmica Populacional , Eutrofização , Atividades Humanas
18.
J Pediatr Gastroenterol Nutr ; 79(4): 915-923, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39032051

RESUMO

OBJECTIVES: In pediatric patients with intestinal failure (IF) due to short bowel syndrome (SBS), we hypothesized that young children, those with shorter residual small bowel and those with congenital malrotation of the bowel would be more likely to undergo pan-enteroscopy. We aimed to determine the feasibility and diagnostic yield of pan-enteroscopy in this cohort. METHODS: We performed a single-center, retrospective study of pediatric patients with IF due to SBS who had undergone at least one GI endoscopic evaluation between January 1, 2018 and January 1, 2023. RESULTS: A pan-enteroscopy might have been possible in 381 of the 431 procedures (206 patients) reviewed. Forty-four (21%) patients underwent 54 pan-enteroscopies. Children with a residual bowel length <35 cm had higher odds of undergoing pan-enteroscopy (odds ratio [OR] 3.72, 95% confidence interval [CI] [1.32, 10.48], p = 0.01), as did patients with periprocedural glucagon-like peptide 2 (GLP-2) analog use (OR 4.30, 95% CI [1.24, 14.95], p = 0.02). Patients with diagnoses other than necrotizing enterocolitis (NEC) tended to be more likely to achieve a pan-enteroscopy (OR 2.73, 95% CI [0.95,7.88], p = 0.06). Evidence of gross and histopathologic abnormalities were found in 77.8% and 78% of the procedures, respectively. No complications were identified. CONCLUSION: In a large cohort of children with SBS, pan-enteroscopy was successfully performed in 14.2% of the procedures and microscopic abnormalities were common. Shorter residual bowel length, underlying diagnoses of non-NEC, and GLP-2 analog use were generally associated with successful pan-enteroscopy, independent of age and several other factors. These data suggest that pan-enteroscopy is feasible and of high-yield in a subset of patients with SBS.


Assuntos
Síndrome do Intestino Curto , Humanos , Síndrome do Intestino Curto/complicações , Estudos Retrospectivos , Feminino , Masculino , Lactente , Pré-Escolar , Criança , Endoscopia Gastrointestinal/métodos , Estudos de Viabilidade , Insuficiência Intestinal/etiologia , Intestino Delgado/patologia , Intestino Delgado/diagnóstico por imagem , Intestino Delgado/anormalidades
19.
Phys Chem Chem Phys ; 26(17): 13420-13431, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38647171

RESUMO

Autoimmune inflammatory diseases, such as rheumatoid arthritis (RA) and ulcerative colitis, are associated with an uncontrolled production of cytokines leading to the pronounced inflammatory response of these disorders. Their therapy is currently focused on the inhibition of cytokine receptors, such as the Janus kinase (JAK) protein family. Tofacitinib and peficitinib are JAK inhibitors that have been recently approved to treat rheumatoid arthritis. In this study, an in-depth analysis was carried out through quantum biochemistry to understand the interactions involved in the complexes formed by JAK1 and tofacitinib or peficitinib. Computational analyses provided new insights into the binding mechanisms between tofacitinib or peficitinib and JAK1. The essential amino acid residues that support the complex are also identified and reported. Additionally, we report new interactions, such as van der Waals; hydrogen bonds; and alkyl, pi-alkyl, and pi-sulfur forces, that stabilize the complexes. The computational results revealed that peficitinib presents a similar affinity to JAK1 compared to tofacitinib based on their interaction energies.


Assuntos
Adamantano/análogos & derivados , Janus Quinase 1 , Niacinamida , Niacinamida/análogos & derivados , Piperidinas , Pirimidinas , Pirimidinas/química , Pirimidinas/farmacologia , Piperidinas/química , Piperidinas/farmacologia , Piperidinas/uso terapêutico , Niacinamida/química , Janus Quinase 1/antagonistas & inibidores , Janus Quinase 1/metabolismo , Janus Quinase 1/química , Humanos , Teoria Quântica , Doenças Autoimunes/tratamento farmacológico , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Ligação de Hidrogênio , Inibidores de Janus Quinases/química , Inibidores de Janus Quinases/uso terapêutico , Inibidores de Janus Quinases/farmacologia , Adamantano/química , Pirróis/química , Pirróis/farmacologia , Simulação de Acoplamento Molecular
20.
Nature ; 554(7691): 249-254, 2018 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-29420472

RESUMO

To facilitate clinical trials of disease-modifying therapies for Alzheimer's disease, which are expected to be most efficacious at the earliest and mildest stages of the disease, supportive biomarker information is necessary. The only validated methods for identifying amyloid-ß deposition in the brain-the earliest pathological signature of Alzheimer's disease-are amyloid-ß positron-emission tomography (PET) imaging or measurement of amyloid-ß in cerebrospinal fluid. Therefore, a minimally invasive, cost-effective blood-based biomarker is desirable. Despite much effort, to our knowledge, no study has validated the clinical utility of blood-based amyloid-ß markers. Here we demonstrate the measurement of high-performance plasma amyloid-ß biomarkers by immunoprecipitation coupled with mass spectrometry. The ability of amyloid-ß precursor protein (APP)669-711/amyloid-ß (Aß)1-42 and Aß1-40/Aß1-42 ratios, and their composites, to predict individual brain amyloid-ß-positive or -negative status was determined by amyloid-ß-PET imaging and tested using two independent data sets: a discovery data set (Japan, n = 121) and a validation data set (Australia, n = 252 including 111 individuals diagnosed using 11C-labelled Pittsburgh compound-B (PIB)-PET and 141 using other ligands). Both data sets included cognitively normal individuals, individuals with mild cognitive impairment and individuals with Alzheimer's disease. All test biomarkers showed high performance when predicting brain amyloid-ß burden. In particular, the composite biomarker showed very high areas under the receiver operating characteristic curves (AUCs) in both data sets (discovery, 96.7%, n = 121 and validation, 94.1%, n = 111) with an accuracy approximately equal to 90% when using PIB-PET as a standard of truth. Furthermore, test biomarkers were correlated with amyloid-ß-PET burden and levels of Aß1-42 in cerebrospinal fluid. These results demonstrate the potential clinical utility of plasma biomarkers in predicting brain amyloid-ß burden at an individual level. These plasma biomarkers also have cost-benefit and scalability advantages over current techniques, potentially enabling broader clinical access and efficient population screening.


Assuntos
Doença de Alzheimer/sangue , Doença de Alzheimer/diagnóstico , Peptídeos beta-Amiloides/sangue , Precursor de Proteína beta-Amiloide/sangue , Fragmentos de Peptídeos/sangue , Idoso , Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Austrália , Biomarcadores/sangue , Biomarcadores/líquido cefalorraquidiano , Biomarcadores/metabolismo , Encéfalo/metabolismo , Estudos de Casos e Controles , Disfunção Cognitiva/sangue , Disfunção Cognitiva/metabolismo , Análise Custo-Benefício , Feminino , Humanos , Imunoprecipitação , Japão , Masculino , Espectrometria de Massas , Fragmentos de Peptídeos/líquido cefalorraquidiano , Fragmentos de Peptídeos/metabolismo , Tomografia por Emissão de Pósitrons , Reprodutibilidade dos Testes
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