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1.
Nat Immunol ; 20(9): 1208-1219, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31384057

RESUMO

Regulatory T cells (Treg cells) deficient in the transcription factor Foxp3 lack suppressor function and manifest an effector T (Teff) cell-like phenotype. We demonstrate that Foxp3 deficiency dysregulates metabolic checkpoint kinase mammalian target of rapamycin (mTOR) complex 2 (mTORC2) signaling and gives rise to augmented aerobic glycolysis and oxidative phosphorylation. Specific deletion of the mTORC2 adaptor gene Rictor in Foxp3-deficient Treg cells ameliorated disease in a Foxo1 transcription factor-dependent manner. Rictor deficiency re-established a subset of Treg cell genetic circuits and suppressed the Teff cell-like glycolytic and respiratory programs, which contributed to immune dysregulation. Treatment of Treg cells from patients with FOXP3 deficiency with mTOR inhibitors similarly antagonized their Teff cell-like program and restored suppressive function. Thus, regulatory function can be re-established in Foxp3-deficient Treg cells by targeting their metabolic pathways, providing opportunities to restore tolerance in Treg cell disorders.


Assuntos
Reprogramação Celular/imunologia , Fatores de Transcrição Forkhead/genética , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Proteína Companheira de mTOR Insensível à Rapamicina/genética , Linfócitos T Reguladores/imunologia , Animais , Células Cultivadas , Feminino , Regulação da Expressão Gênica , Glicólise/fisiologia , Humanos , Masculino , Alvo Mecanístico do Complexo 2 de Rapamicina/antagonistas & inibidores , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosforilação Oxidativa , Transdução de Sinais , Linfócitos T Reguladores/citologia
2.
Genes Dev ; 37(19-20): 883-900, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37890975

RESUMO

Loss-of-function mutations in MECP2 cause Rett syndrome (RTT), a severe neurological disorder that mainly affects girls. Mutations in MECP2 do occur in males occasionally and typically cause severe encephalopathy and premature lethality. Recently, we identified a missense mutation (c.353G>A, p.Gly118Glu [G118E]), which has never been seen before in MECP2, in a young boy who suffered from progressive motor dysfunction and developmental delay. To determine whether this variant caused the clinical symptoms and study its functional consequences, we established two disease models, including human neurons from patient-derived iPSCs and a knock-in mouse line. G118E mutation partially reduces MeCP2 abundance and its DNA binding, and G118E mice manifest RTT-like symptoms seen in the patient, affirming the pathogenicity of this mutation. Using live-cell and single-molecule imaging, we found that G118E mutation alters MeCP2's chromatin interaction properties in live neurons independently of its effect on protein levels. Here we report the generation and characterization of RTT models of a male hypomorphic variant and reveal new insight into the mechanism by which this pathological mutation affects MeCP2's chromatin dynamics. Our ability to quantify protein dynamics in disease models lays the foundation for harnessing high-resolution single-molecule imaging as the next frontier for developing innovative therapies for RTT and other diseases.


Assuntos
Cromatina , Síndrome de Rett , Feminino , Humanos , Masculino , Camundongos , Animais , Cromatina/metabolismo , Encéfalo/metabolismo , Proteína 2 de Ligação a Metil-CpG/genética , Síndrome de Rett/genética , Mutação , Neurônios/metabolismo
3.
Nature ; 622(7982): 255-260, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37648866

RESUMO

Neptune-sized planets exhibit a wide range of compositions and densities, depending on factors related to their formation and evolution history, such as the distance from their host stars and atmospheric escape processes. They can vary from relatively low-density planets with thick hydrogen-helium atmospheres1,2 to higher-density planets with a substantial amount of water or a rocky interior with a thinner atmosphere, such as HD 95338 b (ref. 3), TOI-849 b (ref. 4) and TOI-2196 b (ref. 5). The discovery of exoplanets in the hot-Neptune desert6, a region close to the host stars with a deficit of Neptune-sized planets, provides insights into the formation and evolution of planetary systems, including the existence of this region itself. Here we show observations of the transiting planet TOI-1853 b, which has a radius of 3.46 ± 0.08 Earth radii and orbits a dwarf star every 1.24 days. This planet has a mass of 73.2 ± 2.7 Earth masses, almost twice that of any other Neptune-sized planet known so far, and a density of 9.7 ± 0.8 grams per cubic centimetre. These values place TOI-1853 b in the middle of the Neptunian desert and imply that heavy elements dominate its mass. The properties of TOI-1853 b present a puzzle for conventional theories of planetary formation and evolution, and could be the result of several proto-planet collisions or the final state of an initially high-eccentricity planet that migrated closer to its parent star.

4.
Genes Dev ; 34(15-16): 1075-1088, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32616520

RESUMO

Nonsense-mediated decay (NMD) is a translation-dependent RNA quality control mechanism that occurs in the cytoplasm. However, it is unknown how NMD regulates the stability of RNAs translated at the endoplasmic reticulum (ER). Here, we identify a localized NMD pathway dedicated to ER-translated mRNAs. We previously identified NBAS, a component of the Syntaxin 18 complex involved in Golgi-to-ER trafficking, as a novel NMD factor. Furthermore, we show that NBAS fulfills an independent function in NMD. This ER-NMD pathway requires the interaction of NBAS with the core NMD factor UPF1, which is partially localized at the ER in the proximity of the translocon. NBAS and UPF1 coregulate the stability of ER-associated transcripts, in particular those associated with the cellular stress response. We propose a model where NBAS recruits UPF1 to the membrane of the ER and activates an ER-dedicated NMD pathway, thus providing an ER-protective function by ensuring quality control of ER-translated mRNAs.


Assuntos
Retículo Endoplasmático/metabolismo , Degradação do RNAm Mediada por Códon sem Sentido , Retículo Endoplasmático/enzimologia , Complexo de Golgi/metabolismo , Células HeLa , Humanos , Proteínas de Neoplasias/metabolismo , Proteínas de Neoplasias/fisiologia , Biossíntese de Proteínas , RNA Helicases/metabolismo
5.
Nature ; 583(7814): 39-42, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32612222

RESUMO

The interiors of giant planets remain poorly understood. Even for the planets in the Solar System, difficulties in observation lead to large uncertainties in the properties of planetary cores. Exoplanets that have undergone rare evolutionary processes provide a route to understanding planetary interiors. Planets found in and near the typically barren hot-Neptune 'desert'1,2 (a region in mass-radius space that contains few planets) have proved to be particularly valuable in this regard. These planets include HD149026b3, which is thought to have an unusually massive core, and recent discoveries such as LTT9779b4 and NGTS-4b5, on which photoevaporation has removed a substantial part of their outer atmospheres. Here we report observations of the planet TOI-849b, which has a radius smaller than Neptune's but an anomalously large mass of [Formula: see text] Earth masses and a density of [Formula: see text] grams per cubic centimetre, similar to Earth's. Interior-structure models suggest that any gaseous envelope of pure hydrogen and helium consists of no more than [Formula: see text] per cent of the total planetary mass. The planet could have been a gas giant before undergoing extreme mass loss via thermal self-disruption or giant planet collisions, or it could have avoided substantial gas accretion, perhaps through gap opening or late formation6. Although photoevaporation rates cannot account for the mass loss required to reduce a Jupiter-like gas giant, they can remove a small (a few Earth masses) hydrogen and helium envelope on timescales of several billion years, implying that any remaining atmosphere on TOI-849b is likely to be enriched by water or other volatiles from the planetary interior. We conclude that TOI-849b is the remnant core of a giant planet.

6.
J Neurosci ; 44(28)2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38871463

RESUMO

Interspecies comparisons are key to deriving an understanding of the behavioral and neural correlates of human cognition from animal models. We perform a detailed comparison of the strategies of female macaque monkeys to male and female humans on a variant of the Wisconsin Card Sorting Test (WCST), a widely studied and applied task that provides a multiattribute measure of cognitive function and depends on the frontal lobe. WCST performance requires the inference of a rule change given ambiguous feedback. We found that well-trained monkeys infer new rules three times more slowly than minimally instructed humans. Input-dependent hidden Markov model-generalized linear models were fit to their choices, revealing hidden states akin to feature-based attention in both species. Decision processes resembled a win-stay, lose-shift strategy with interspecies similarities as well as key differences. Monkeys and humans both test multiple rule hypotheses over a series of rule-search trials and perform inference-like computations to exclude candidate choice options. We quantitatively show that perseveration, random exploration, and poor sensitivity to negative feedback account for the slower task-switching performance in monkeys.


Assuntos
Macaca mulatta , Animais , Feminino , Masculino , Humanos , Adulto , Aprendizagem/fisiologia , Adulto Jovem , Especificidade da Espécie , Comportamento de Escolha/fisiologia , Tempo de Reação/fisiologia
7.
Nat Methods ; 19(11): 1393-1402, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36216958

RESUMO

We present Light-Seq, an approach for multiplexed spatial indexing of intact biological samples using light-directed DNA barcoding in fixed cells and tissues followed by ex situ sequencing. Light-Seq combines spatially targeted, rapid photocrosslinking of DNA barcodes onto complementary DNAs in situ with a one-step DNA stitching reaction to create pooled, spatially indexed sequencing libraries. This light-directed barcoding enables in situ selection of multiple cell populations in intact fixed tissue samples for full-transcriptome sequencing based on location, morphology or protein stains, without cellular dissociation. Applying Light-Seq to mouse retinal sections, we recovered thousands of differentially enriched transcripts from three cellular layers and discovered biomarkers for a very rare neuronal subtype, dopaminergic amacrine cells, from only four to eight individual cells per section. Light-Seq provides an accessible workflow to combine in situ imaging and protein staining with next generation sequencing of the same cells, leaving the sample intact for further analysis post-sequencing.


Assuntos
DNA , Sequenciamento de Nucleotídeos em Larga Escala , Animais , Camundongos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , DNA Complementar , DNA/genética
8.
Cereb Cortex ; 34(2)2024 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-38216528

RESUMO

Our brains extract structure from the environment and form predictions given past experience. Predictive circuits have been identified in wide-spread cortical regions. However, the contribution of medial temporal structures in predictions remains under-explored. The hippocampus underlies sequence detection and is sensitive to novel stimuli, sufficient to gain access to memory, while the amygdala to novelty. Yet, their electrophysiological profiles in detecting predictable and unpredictable deviant auditory events remain unknown. Here, we hypothesized that the hippocampus would be sensitive to predictability, while the amygdala to unexpected deviance. We presented epileptic patients undergoing presurgical monitoring with standard and deviant sounds, in predictable or unpredictable contexts. Onsets of auditory responses and unpredictable deviance effects were detected earlier in the temporal cortex compared with the amygdala and hippocampus. Deviance effects in 1-20 Hz local field potentials were detected in the lateral temporal cortex, irrespective of predictability. The amygdala showed stronger deviance in the unpredictable context. Low-frequency deviance responses in the hippocampus (1-8 Hz) were observed in the predictable but not in the unpredictable context. Our results reveal a distributed network underlying the generation of auditory predictions and suggest that the neural basis of sensory predictions and prediction error signals needs to be extended.


Assuntos
Córtex Auditivo , Humanos , Córtex Auditivo/fisiologia , Lobo Temporal , Tonsila do Cerebelo , Encéfalo , Hipocampo , Estimulação Acústica , Percepção Auditiva/fisiologia , Potenciais Evocados Auditivos/fisiologia
9.
J Allergy Clin Immunol ; 153(5): 1423-1431.e2, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38290608

RESUMO

BACKGROUND: P47phox (neutrophil cytosolic factor-1) deficiency is the most common cause of autosomal recessive chronic granulomatous disease (CGD) and is considered to be associated with a milder clinical phenotype. Allogeneic hematopoietic cell transplantation (HCT) for p47phox CGD is not well-described. OBJECTIVES: We sought to study HCT for p47phox CGD in North America. METHODS: Thirty patients with p47phox CGD who received allogeneic HCT at Primary Immune Deficiency Treatment Consortium centers since 1995 were included. RESULTS: Residual oxidative activity was present in 66.7% of patients. In the year before HCT, there were 0.38 CGD-related infections per person-years. Inflammatory diseases, predominantly of the lungs and bowel, occurred in 36.7% of the patients. The median age at HCT was 9.1 years (range 1.5-23.6 years). Most HCTs (90%) were performed after using reduced intensity/toxicity conditioning. HCT sources were HLA-matched (40%) and -mismatched (10%) related donors or HLA-matched (36.7%) and -mismatched (13.3%) unrelated donors. CGD-related infections after HCT decreased significantly to 0.06 per person-years (P = .038). The frequency of inflammatory bowel disease and the use of steroids also decreased. The cumulative incidence of graft failure and second HCT was 17.9%. The 2-year overall and event-free survival were 92.3% and 82.1%, respectively, while at 5 years they were 85.7% and 77.0%, respectively. In the surviving patients evaluated, ≥95% donor myeloid chimerism at 1 and 2 years after HCT was 93.8% and 87.5%, respectively. CONCLUSIONS: Patients with p47phox CGD suffer from a significant disease burden that can be effectively alleviated by HCT. Similar to other forms of CGD, HCT should be considered for patients with p47phox CGD.


Assuntos
Doença Granulomatosa Crônica , Transplante de Células-Tronco Hematopoéticas , NADPH Oxidases , Humanos , Doença Granulomatosa Crônica/terapia , Doença Granulomatosa Crônica/genética , NADPH Oxidases/genética , Masculino , Feminino , Criança , Pré-Escolar , Adolescente , Lactente , Adulto Jovem , Transplante Homólogo , Condicionamento Pré-Transplante/métodos , Doença Enxerto-Hospedeiro , Adulto , Resultado do Tratamento
10.
Biochemistry ; 63(5): 711-722, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38380587

RESUMO

The cytochrome P450 enzyme CYP121A1 endogenously catalyzes the formation of a carbon-carbon bond between the two phenol groups of dicyclotyrosine (cYY) in Mycobacterium tuberculosis (Mtb). One of 20 CYP enzymes in Mtb, CYP121A1 continues to garner significant interest as a potential drug target. The accompanying reports the use of 19F NMR spectroscopy, reconstituted activity assays, and molecular dynamics simulations to investigate the significance of hydrogen bonding interactions that were theorized to stabilize a static active site water network. The active site residue Asn-85, whose hydrogen bonds with the diketopiperazine ring of cYY contributes to a contiguous active site water network in the absence of cYY, was mutated to a serine (N85S) and to a glutamine (N85Q). These conservative changes in the hydrogen bond donor side chain result in inactivation of the enzyme. Moreover, the N85S mutation induces reverse type-I binding as measured by absorbance difference spectra. NMR spectra monitoring the ligand-adaptive FG-loop and the active site Trp-182 side chain confirm that disruption of the active site water network also significantly alters the structure of the active site. These data were consistent with dynamics simulations of N85S and N85Q that demonstrate that a compromised water network is responsible for remodeling of the active site B-helix and a repositioning of cYY toward the heme. These findings implicate a slowly exchanging water network as a critical factor in CYP121A1 function and a likely contributor to the unusual rigidity of the structure.


Assuntos
Mycobacterium tuberculosis , Domínio Catalítico , Asparagina , Água , Sistema Enzimático do Citocromo P-450/metabolismo , Carbono , Ligação de Hidrogênio
11.
J Biol Chem ; 299(12): 105396, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37890781

RESUMO

Scaffold proteins help mediate interactions between protein partners, often to optimize intracellular signaling. Herein, we use comparative, biochemical, biophysical, molecular, and cellular approaches to investigate how the scaffold protein NEMO contributes to signaling in the NF-κB pathway. Comparison of NEMO and the related protein optineurin from a variety of evolutionarily distant organisms revealed that a central region of NEMO, called the Intervening Domain (IVD), is conserved between NEMO and optineurin. Previous studies have shown that this central core region of the IVD is required for cytokine-induced activation of IκB kinase (IKK). We show that the analogous region of optineurin can functionally replace the core region of the NEMO IVD. We also show that an intact IVD is required for the formation of disulfide-bonded dimers of NEMO. Moreover, inactivating mutations in this core region abrogate the ability of NEMO to form ubiquitin-induced liquid-liquid phase separation droplets in vitro and signal-induced puncta in vivo. Thermal and chemical denaturation studies of truncated NEMO variants indicate that the IVD, while not intrinsically destabilizing, can reduce the stability of surrounding regions of NEMO due to the conflicting structural demands imparted on this region by flanking upstream and downstream domains. This conformational strain in the IVD mediates allosteric communication between the N- and C-terminal regions of NEMO. Overall, these results support a model in which the IVD of NEMO participates in signal-induced activation of the IKK/NF-κB pathway by acting as a mediator of conformational changes in NEMO.


Assuntos
Quinase I-kappa B , Quinase I-kappa B/química , Quinase I-kappa B/metabolismo , NF-kappa B/metabolismo , Separação de Fases , Transdução de Sinais , Ubiquitina/metabolismo , Humanos
12.
Circulation ; 147(22): 1654-1669, 2023 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-37070436

RESUMO

BACKGROUND: Sodium-glucose co-transporter 2 inhibitors (SGLT2i) have emerged as a paramount treatment for patients with heart failure (HF), irrespective of underlying reduced or preserved ejection fraction. However, a definite cardiac mechanism of action remains elusive. Derangements in myocardial energy metabolism are detectable in all HF phenotypes, and it was proposed that SGLT2i may improve energy production. The authors aimed to investigate whether treatment with empagliflozin leads to changes in myocardial energetics, serum metabolomics, and cardiorespiratory fitness. METHODS: EMPA-VISION (Assessment of Cardiac Energy Metabolism, Function and Physiology in Patients With Heart Failure Taking Empagliflozin) is a prospective, randomized, double-blind, placebo-controlled, mechanistic trial that enrolled 72 symptomatic patients with chronic HF with reduced ejection fraction (HFrEF; n=36; left ventricular ejection fraction ≤40%; New York Heart Association class ≥II; NT-proBNP [N-terminal pro-B-type natriuretic peptide] ≥125 pg/mL) and HF with preserved ejection fraction (HFpEF; n=36; left ventricular ejection fraction ≥50%; New York Heart Association class ≥II; NT-proBNP ≥125 pg/mL). Patients were stratified into respective cohorts (HFrEF versus HFpEF) and randomly assigned to empagliflozin (10 mg; n=35: 17 HFrEF and 18 HFpEF) or placebo (n=37: 19 HFrEF and 18 HFpEF) once daily for 12 weeks. The primary end point was a change in the cardiac phosphocreatine:ATP ratio (PCr/ATP) from baseline to week 12, determined by phosphorus magnetic resonance spectroscopy at rest and during peak dobutamine stress (65% of age-maximum heart rate). Mass spectrometry on a targeted set of 19 metabolites was performed at baseline and after treatment. Other exploratory end points were investigated. RESULTS: Empagliflozin treatment did not change cardiac energetics (ie, PCr/ATP) at rest in HFrEF (adjusted mean treatment difference [empagliflozin - placebo], -0.25 [95% CI, -0.58 to 0.09]; P=0.14) or HFpEF (adjusted mean treatment difference, -0.16 [95% CI, -0.60 to 0.29]; P=0.47]. Likewise, there were no changes in PCr/ATP during dobutamine stress in HFrEF (adjusted mean treatment difference, -0.13 [95% CI, -0.35 to 0.09]; P=0.23) or HFpEF (adjusted mean treatment difference, -0.22 [95% CI, -0.66 to 0.23]; P=0.32). No changes in serum metabolomics or levels of circulating ketone bodies were observed. CONCLUSIONS: In patients with either HFrEF or HFpEF, treatment with 10 mg of empagliflozin once daily for 12 weeks did not improve cardiac energetics or change circulating serum metabolites associated with energy metabolism when compared with placebo. Based on our results, it is unlikely that enhancing cardiac energy metabolism mediates the beneficial effects of SGLT2i in HF. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT03332212.


Assuntos
Insuficiência Cardíaca , Humanos , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/tratamento farmacológico , Volume Sistólico , Função Ventricular Esquerda , Estudos Prospectivos , Dobutamina/farmacologia , Metabolismo Energético , Trifosfato de Adenosina
13.
Physiology (Bethesda) ; 38(2): 0, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36099270

RESUMO

Developing a more comprehensive understanding of the physiological underpinnings of mental illness, precision medicine has the potential to revolutionize psychiatric care. With recent breakthroughs in next-generation multi-omics technologies and data analytics, it is becoming more feasible to leverage multimodal biomarkers, from genetic variants to neuroimaging biomarkers, to objectify diagnostics and treatment decisions in psychiatry and improve patient outcomes. Ongoing work in precision psychiatry will parallel progress in precision oncology and cardiology to develop an expanded suite of blood- and neuroimaging-based diagnostic tests, empower monitoring of treatment efficacy over time, and reduce patient exposure to ineffective treatments. The emerging model of precision psychiatry has the potential to mitigate some of psychiatry's most pressing issues, including improving disease classification, lengthy treatment duration, and suboptimal treatment outcomes. This narrative-style review summarizes some of the emerging breakthroughs and recurring challenges in the application of precision medicine approaches to mental health care.


Assuntos
Transtornos Mentais , Neoplasias , Humanos , Medicina de Precisão , Saúde Mental , Transtornos Mentais/terapia , Transtornos Mentais/genética , Biomarcadores
14.
Lancet ; 402(10396): 129-140, 2023 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-37352885

RESUMO

BACKGROUND: Severe combined immunodeficiency (SCID) is fatal unless durable adaptive immunity is established, most commonly through allogeneic haematopoietic cell transplantation (HCT). The Primary Immune Deficiency Treatment Consortium (PIDTC) explored factors affecting the survival of individuals with SCID over almost four decades, focusing on the effects of population-based newborn screening for SCID that was initiated in 2008 and expanded during 2010-18. METHODS: We analysed transplantation-related data from children with SCID treated at 34 PIDTC sites in the USA and Canada, using the calendar time intervals 1982-89, 1990-99, 2000-09, and 2010-18. Categorical variables were compared by χ2 test and continuous outcomes by the Kruskal-Wallis test. Overall survival was estimated by the Kaplan-Meier method. A multivariable analysis using Cox proportional hazards regression models examined risk factors for HCT outcomes, including the variables of time interval of HCT, infection status and age at HCT, trigger for diagnosis, SCID type and genotype, race and ethnicity of the patient, non-HLA-matched sibling donor type, graft type, GVHD prophylaxis, and conditioning intensity. FINDINGS: For 902 children with confirmed SCID, 5-year overall survival remained unchanged at 72%-73% for 28 years until 2010-18, when it increased to 87% (95% CI 82·1-90·6; n=268; p=0·0005). For children identified as having SCID by newborn screening since 2010, 5-year overall survival was 92·5% (95% CI 85·8-96·1), better than that of children identified by clinical illness or family history in the same interval (79·9% [69·5-87·0] and 85·4% [71·8-92·8], respectively [p=0·043]). Multivariable analysis demonstrated that the factors of active infection (hazard ratio [HR] 2·41, 95% CI 1·56-3·72; p<0·0001), age 3·5 months or older at HCT (2·12, 1·38-3·24; p=0·001), Black or African-American race (2·33, 1·56-3·46; p<0·0001), and certain SCID genotypes to be associated with lower overall survival during all time intervals. Moreover, after adjusting for several factors in this multivariable analysis, HCT after 2010 no longer conveyed a survival advantage over earlier time intervals studied (HR 0·73, 95% CI 0·43-1·26; p=0·097). This indicated that younger age and freedom from infections at HCT, both directly driven by newborn screening, were the main drivers for recent improvement in overall survival. INTERPRETATION: Population-based newborn screening has facilitated the identification of infants with SCID early in life, in turn leading to prompt HCT while avoiding infections. Public health programmes worldwide can benefit from this definitive demonstration of the value of newborn screening for SCID. FUNDING: National Institute of Allergy and Infectious Diseases, Office of Rare Diseases Research, and National Center for Advancing Translational Sciences.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Imunodeficiência Combinada Severa , Humanos , Recém-Nascido , Transplante de Células-Tronco Hematopoéticas/métodos , Estudos Longitudinais , Triagem Neonatal , Modelos de Riscos Proporcionais , Imunodeficiência Combinada Severa/diagnóstico , Imunodeficiência Combinada Severa/terapia , Imunodeficiência Combinada Severa/genética
15.
N Engl J Med ; 384(25): 2406-2417, 2021 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-34161705

RESUMO

BACKGROUND: Autophagy is the major intracellular degradation route in mammalian cells. Systemic ablation of core autophagy-related (ATG) genes in mice leads to embryonic or perinatal lethality, and conditional models show neurodegeneration. Impaired autophagy has been associated with a range of complex human diseases, yet congenital autophagy disorders are rare. METHODS: We performed a genetic, clinical, and neuroimaging analysis involving five families. Mechanistic investigations were conducted with the use of patient-derived fibroblasts, skeletal muscle-biopsy specimens, mouse embryonic fibroblasts, and yeast. RESULTS: We found deleterious, recessive variants in human ATG7, a core autophagy-related gene encoding a protein that is indispensable to classical degradative autophagy. Twelve patients from five families with distinct ATG7 variants had complex neurodevelopmental disorders with brain, muscle, and endocrine involvement. Patients had abnormalities of the cerebellum and corpus callosum and various degrees of facial dysmorphism. These patients have survived with impaired autophagic flux arising from a diminishment or absence of ATG7 protein. Although autophagic sequestration was markedly reduced, evidence of basal autophagy was readily identified in fibroblasts and skeletal muscle with loss of ATG7. Complementation of different model systems by deleterious ATG7 variants resulted in poor or absent autophagic function as compared with the reintroduction of wild-type ATG7. CONCLUSIONS: We identified several patients with a neurodevelopmental disorder who have survived with a severe loss or complete absence of ATG7, an essential effector enzyme for autophagy without a known functional paralogue. (Funded by the Wellcome Centre for Mitochondrial Research and others.).


Assuntos
Anormalidades Múltiplas/genética , Ataxia/genética , Proteína 7 Relacionada à Autofagia/genética , Autofagia/genética , Deficiências do Desenvolvimento/genética , Mutação de Sentido Incorreto , Adolescente , Adulto , Autofagia/fisiologia , Proteína 7 Relacionada à Autofagia/fisiologia , Células Cultivadas , Cerebelo/anormalidades , Simulação por Computador , Face/anormalidades , Feminino , Fibroblastos , Genes Recessivos , Humanos , Lactente , Masculino , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Malformações do Sistema Nervoso/genética , Linhagem , Fenótipo
16.
Magn Reson Med ; 92(4): 1323-1337, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38775024

RESUMO

PURPOSE: Prostate tissue has a complex microstructure, mainly composed of epithelial and stromal cells, and of extracellular (acinar-luminal) spaces. Diffusion-weighted MR spectroscopy (DW-MRS) is ideally suited to explore complex microstructure in vivo with metabolites selectively distributed in different subspaces. To date, this technique has been applied to brain and muscle. This study presents the development and pioneering utilization of 1H-DW-MRS in the prostate, accompanied by in vitro studies to support interpretations of in vivo findings. METHODS: Nine healthy volunteers underwent a prostate MR examination (mean age, 56 years; range, 31-66). Metabolic complexation was studied in vitro using solutions with major compounds found in prostatic fluid of the lumen. DW-MRS was performed at 3 T with a non-water-suppressed single-voxel sequence with metabolite-cycling to concurrently measure metabolite and water signals. The water signal was used in postprocessing as a reference in a motion-compensation scheme. The spectra were fitted simultaneously in the spectral and diffusion-weighting dimensions. Apparent diffusion coefficients (ADCs) were derived by fitting signal decays that were assumed to be mono-exponential for metabolites and biexponential for water. RESULTS: DW-MRS of the prostate revealed relatively low ADCs for Cho and Cr compounds, aligning with their intracellular location and higher ADCs for citrate and spermine supporting their luminal origin. In vitro assessments of the ADCs of citrate and spermine demonstrated their complex formation and protein binding. Tissue concentrations of MRS-detectable metabolites were as expected for the voxel location. CONCLUSIONS: This work successfully demonstrates the feasibility of 1H-DW-MRS of the prostate and its potential for providing valuable microstructural information.


Assuntos
Imagem de Difusão por Ressonância Magnética , Próstata , Masculino , Humanos , Próstata/diagnóstico por imagem , Próstata/metabolismo , Pessoa de Meia-Idade , Adulto , Idoso , Imagem de Difusão por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
18.
Artigo em Inglês | MEDLINE | ID: mdl-38878138

RESUMO

In health, the human heart is able to match ATP supply and demand perfectly. It requires 6 kg of ATP per day to satisfy demands of external work (mechanical force generation) and internal work (ion movements and basal metabolism). The heart is able to link supply with demand via direct responses to ADP and AMP concentrations but calcium concentrations within myocytes play a key role, signalling both inotropy, chronotropy and matched increases in ATP production. Calcium/calmodulin-dependent protein kinase (CaMKII) is a key adapter to increased workload, facilitating a greater and more rapid calcium concentration change. In the failing heart, this is dysfunctional and ATP supply is impaired. This review aims to examine the mechanisms and pathologies that link increased energy demand to this disrupted situation. We examine the roles of calcium loading, oxidative stress, mitochondrial structural abnormalities and damage-associated molecular patterns.

19.
Artigo em Inglês | MEDLINE | ID: mdl-38478156

RESUMO

The COVID-19 pandemic contributed to worsening mental health across the globe. The pandemic may have been especially impactful on those experiencing heightened psychosis spectrum symptomatology given greater pre-pandemic social isolation and increased vulnerability to stress. Yet, few studies exploring the impact of the COVID-19 pandemic on perceptions of social relationships and mental health have sampled individuals high in psychosis spectrum symptomatology, including those with psychosis spectrum disorders. Utilizing a mixed transdiagnostic community sample enriched for psychotic spectrum disorders, this longitudinal study investigated whether perceptions of social relationships and psychiatric symptoms changed during the COVID-19 pandemic, whether pandemic-related impacts were associated with social perceptions and symptomatology, and whether paranoid ideation was related to perceptions of the government response to the COVID-19 pandemic. Pandemic impacts were not uniform, with participants reporting a range of adverse impacts including poorer health-related behaviors, difficulties fulfilling basic needs, and medical related challenges. Results indicated that compared to pre-pandemic assessments, perceived rejection and hostility increased during the COVID-19 pandemic. Participants who experienced more pandemic-related impacts reported less social support, more social distress, greater negative affect, and greater paranoid ideation. Paranoid ideation was related to more negative perceptions of the government's response to the pandemic. These findings demonstrate the importance of assessing individual differences in pandemic-related impacts and the clinical consequences of such impacts. Results also suggest that those high in paranoid ideation may be reluctant to engage in government recommended protective health behaviors to limit the spread of COVID-19.

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