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1.
PLoS Biol ; 21(8): e3002271, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37651406

RESUMO

Taste bud cells are constantly replaced in taste buds as old cells die and new cells migrate into the bud. The perception of taste relies on new taste bud cells integrating with existing neural circuitry, yet how these new cells connect with a taste ganglion neuron is unknown. Do taste ganglion neurons remodel to accommodate taste bud cell renewal? If so, how much of the structure of taste axons is fixed and how much remodels? Here, we measured the motility and branching of individual taste arbors (the portion of the axon innervating taste buds) in mice over time with two-photon in vivo microscopy. Terminal branches of taste arbors continuously and rapidly remodel within the taste bud. This remodeling is faster than predicted by taste bud cell renewal, with terminal branches added and lost concurrently. Surprisingly, blocking entry of new taste bud cells with chemotherapeutic agents revealed that remodeling of the terminal branches on taste arbors does not rely on the renewal of taste bud cells. Although terminal branch remodeling was fast and intrinsically controlled, no new arbors were added to taste buds, and few were lost over 100 days. Taste ganglion neurons maintain a stable number of arbors that are each capable of high-speed remodeling. We propose that terminal branch plasticity permits arbors to locate new taste bud cells, while stability of arbor number supports constancy in the degree of connectivity and function for each neuron over time.


Assuntos
Interneurônios , Paladar , Animais , Camundongos , Neurônios , Axônios , Microscopia Intravital
2.
J Neurosci ; 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39379155

RESUMO

Peripheral taste neurons exhibit functional, genetic, and morphological diversity, yet understanding how or if these attributes combine into taste neuron types remains unclear. In this study, we used male and female mice to relate taste bud innervation patterns to the function of a subset of proenkephalin-expressing (Penk+) taste neurons. We found that taste arbors (the portion of the axon within the taste bud) stemming from Penk+ neurons displayed diverse branching patterns and lacked stereotypical endings. The range in complexity observed for individual taste arbors from Penk+ neurons mirrored the entire population, suggesting that taste arbor morphologies are not primarily regulated by neuron type. Notably, the distinguishing feature of arbors from Penk+ neurons was their propensity to come within 110 nm (in apposition with) different types of taste-transducing cells within the taste bud. This finding is contrary to the expectation of genetically defined taste neuron types that functionally represent a single stimulus. Consistently, further investigation of Penk+ neuron function revealed that they are more likely to respond to innately aversive stimuli -sour, bitter and high salt concentrations - as compared to the full taste population. Penk+ neurons are less likely to respond to non-aversive stimuli -sucrose, umami, and low salt- compared to the full population. Our data support the presence of a genetically defined neuron type in the geniculate ganglion that is responsive to innately aversive stimuli. This implies that genetic expression might categorize peripheral taste neurons into hedonic groups, rather than simply identifying neurons that respond to a single stimulus.Significance Statement Peripheral taste neuron coding has been heavily debated. Our study delves into this issue by leveraging genetic expression in a specific neuron subset to relate peripheral innervation patterns to functional taste responses. We examined a taste neuron type that appears to be in apposition with multiple taste-transducing cell types and responds to innately aversive concentrations of sour, bitter, and high NaCl stimuli. These collective observations suggest that genetic markers can delineate groups of neurons sharing similar hedonic responses rather than categorizing neurons solely based on individual taste qualities.

3.
J Infect Dis ; 230(3): e753-e757, 2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-38723177

RESUMO

Maintaining high-affinity antibodies after vaccination may be important for long-lasting immunity to malaria, but data on induction and kinetics of affinity is lacking. In a phase 1 malaria vaccine trial, antibody affinity increased following a second vaccination but declined substantially over 12 months, suggesting poor maintenance of high-affinity antibodies. CLINICAL TRIALS REGISTRATION: Australian New Zealand Clinical Trials Registry ACTRN12607000552482.


Assuntos
Anticorpos Antiprotozoários , Afinidade de Anticorpos , Vacinas Antimaláricas , Malária Falciparum , Plasmodium falciparum , Humanos , Vacinas Antimaláricas/imunologia , Vacinas Antimaláricas/administração & dosagem , Plasmodium falciparum/imunologia , Malária Falciparum/prevenção & controle , Malária Falciparum/imunologia , Anticorpos Antiprotozoários/imunologia , Merozoítos/imunologia , Adulto , Vacinação , Masculino , Feminino , Adulto Jovem , Austrália , Adolescente
4.
Immunity ; 42(3): 580-90, 2015 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-25786180

RESUMO

Antibodies play major roles in immunity to malaria; however, a limited understanding of mechanisms mediating protection is a major barrier to vaccine development. We have demonstrated that acquired human anti-malarial antibodies promote complement deposition on the merozoite to mediate inhibition of erythrocyte invasion through C1q fixation and activation of the classical complement pathway. Antibody-mediated complement-dependent (Ab-C') inhibition was the predominant invasion-inhibitory activity of human antibodies; most antibodies were non-inhibitory without complement. Inhibitory activity was mediated predominately via C1q fixation, and merozoite surface proteins 1 and 2 were identified as major targets. Complement fixation by antibodies was very strongly associated with protection from both clinical malaria and high-density parasitemia in a prospective longitudinal study of children. Ab-C' inhibitory activity could be induced by human immunization with a candidate merozoite surface-protein vaccine. Our findings demonstrate that human anti-malarial antibodies have evolved to function by fixing complement for potent invasion-inhibitory activity and protective immunity.


Assuntos
Anticorpos Antiprotozoários/biossíntese , Complemento C1q/metabolismo , Vacinas Antimaláricas/imunologia , Malária Falciparum/prevenção & controle , Merozoítos/imunologia , Parasitemia/prevenção & controle , Plasmodium falciparum/imunologia , Adolescente , Animais , Antígenos de Protozoários/genética , Antígenos de Protozoários/imunologia , Criança , Pré-Escolar , Testes de Fixação de Complemento , Via Clássica do Complemento , Eritrócitos/imunologia , Eritrócitos/parasitologia , Feminino , Expressão Gênica , Interações Hospedeiro-Patógeno , Humanos , Imunoglobulina G/biossíntese , Vacinas Antimaláricas/administração & dosagem , Malária Falciparum/imunologia , Malária Falciparum/parasitologia , Masculino , Proteína 1 de Superfície de Merozoito/antagonistas & inibidores , Proteína 1 de Superfície de Merozoito/genética , Proteína 1 de Superfície de Merozoito/imunologia , Parasitemia/imunologia , Parasitemia/parasitologia , Estudos Prospectivos , Proteínas de Protozoários/antagonistas & inibidores , Proteínas de Protozoários/genética , Proteínas de Protozoários/imunologia
5.
Eur Radiol ; 34(3): 1921-1931, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37656178

RESUMO

OBJECTIVE: To investigate the feasibility and image quality of high-pitch CT pulmonary angiography (CTPA) with reduced iodine volume in normal weight patients. METHODS: In total, 81 normal weight patients undergoing CTPA for suspected pulmonary arterial embolism were retrospectively included: 41 in high-pitch mode with 20 mL of contrast medium (CM); and 40 with normal pitch and 50 mL of CM. Subjective image quality was assessed and rated on a 3-point scale. For objective image quality, attenuation and noise values were measured in all pulmonary arteries from the trunk to segmental level. Contrast-to-noise ratio (CNR) was calculated. Radiation dose estimations were recorded. RESULTS: There were no statistically significant differences in patient and scan demographics between high-pitch and standard CTPA. Subjective image quality was rated good to excellent in over 90% of all exams with no significant group differences (p = 0.32). Median contrast opacification was lower in high-pitch CTPA (283.18 [216.06-368.67] HU, 386.81 [320.57-526.12] HU; p = 0.0001). CNR reached a minimum of eight in all segmented arteries, but was lower in high-pitch CTPA (8.79 [5.82-12.42], 11.01 [9.19-17.90]; p = 0.005). Median effective dose of high-pitch CTPA was lower (1.04 [0.72-1.27] mSv/mGy·cm; 1.49 [1.07-2.05] mSv/mGy·cm; p < 0.0001). CONCLUSION: High-pitch CTPA using ultra-low contrast volume (20 mL) rendered diagnostic images for the detection of pulmonary arterial embolism in most instances. Compared to standard CTPA, the high-pitch CTPA exams with drastically reduced contrast medium volume had also concomitantly reduced radiation exposure. However, objective image quality of high-pitch CTPA was worse, though likely still within acceptable limits for confident diagnosis. CLINICAL RELEVANCE: This study provides valuable insights on the performance of a high-pitch dual-source CTPA protocol, offering potential benefits in reducing contrast medium and radiation dose while maintaining sufficient image quality for accurate diagnosis in patients suspected of pulmonary embolism. KEY POINTS: • High-pitch CT pulmonary angiography (CTPA) with ultra-low volume of contrast medium and reduced radiation dose renders diagnostic examinations with comparable subjective image quality to standard CTPA in most patients. • Objective image quality of high-pitch CTPA is reduced compared to standard CTPA, but contrast opacification and contrast-to-noise ratio remain above diagnostic thresholds. • Challenges of high-pitch CTPA may potentially be encountered in patients with severe heart failure or when performing a Valsalva maneuver during the examination.


Assuntos
Hipertensão Pulmonar , Embolia Pulmonar , Humanos , Estudos Retrospectivos , Embolia Pulmonar/diagnóstico por imagem , Artéria Pulmonar/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Angiografia/métodos , Doses de Radiação , Angiografia por Tomografia Computadorizada/métodos , Meios de Contraste
6.
J Fam Nurs ; 30(3): 218-231, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39206750

RESUMO

Caregiving is often associated with negative physical and mental health outcomes, and as the COVID-19 pandemic escalated, caregivers experienced more burden and provided more care with substantially less support. Digital resources may have been one way caregivers managed demands for care and needs for information. This mixed-methods study included surveys and semi-structured interviews with caregivers (n = 11) to describe experiences and use of digital health resources during the COVID-19 pandemic. Caregivers most often provided significant physical care and experienced reduced or no social support during the pandemic. Caregivers reported the need for improving the quality of telehealth services and digital health resources. COVID-19 will not likely be the last pandemic faced by contemporary society. Measures should be taken to reduce the anticipated negative impacts on caregivers and those receiving care during future pandemics.


Assuntos
COVID-19 , Cuidadores , Telemedicina , Humanos , COVID-19/enfermagem , Cuidadores/psicologia , Feminino , Masculino , Idoso , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Adulto , Apoio Social , SARS-CoV-2 , Pandemias , Inquéritos e Questionários , Sobrecarga do Cuidador/psicologia , Saúde Digital
7.
Analyst ; 148(12): 2745-2757, 2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37191142

RESUMO

Raman spectroscopy enables the label-free assessment of cellular composition. While live cell analysis is the most accurate approach for cellular Raman spectroscopy, the analysis of fixed cells has proved to be very useful, particularly in collaborative projects where samples need to be serially examined by different laboratories or stored and reanalyzed at a later date. However, many chemicals that are widely used for cell fixation directly affect cellular biomolecules, yielding Raman spectra with missing or altered information. In this article, we compared the suitability of dry-fixation with saline versus chemical fixatives. We compared the Raman spectroscopy of saline dry-fixed cells with the more commonly used formaldehyde and methanol fixation and found that dry-fixed cell spectra preserved more cellular information than either chemical fixative. We also assessed the stability of dry-fixed cells over time and found that they were stable for at least 5 months. Finally, a comparison of dry-fixed and live cell spectra revealed effects due to the hydration state of the cells since they were recovered upon rehydrating dry-fixed samples. Thus, for fixed cell Raman spectroscopy, we recommend dry-fixation with unbuffered saline as a superior method to formaldehyde or methanol fixation.


Assuntos
Metanol , Análise Espectral Raman , Fixação de Tecidos/métodos , Análise Espectral Raman/métodos , Metanol/química , Fixadores/química , Fixadores/farmacologia , Formaldeído/química
8.
BMC Nephrol ; 24(1): 41, 2023 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-36814219

RESUMO

BACKGROUND: Foetal and early childhood development contributes to the risk of adult non-communicable diseases such as hypertension and cardiovascular disease. We aimed to investigate whether kidney size at birth is associated with markers of kidney function at 7-11 years. METHODS: Foetal kidney dimensions were measured using ultrasound scans at 34 weeks gestation and used to derive kidney volume (cm3) in 1802 participants in the Born in Bradford (BiB) birth cohort. Blood and urine samples were taken from those who participated in the BiB follow-up at 7-11 years (n = 630) and analysed for serum creatinine, cystatin C, urea, and urinary albumin to creatinine ratio (ACR), protein to creatinine ratio (PCR) and retinol binding protein (RBP). Estimated glomerular filtration rate (eGFR) was calculated using Schwartz creatinine only and combined with cystatin C, and cystatin C only Zappitelli and Filler equations. Linear regression was used to examine the association between foetal kidney volume and eGFR, ACR, PCR and blood pressure, unadjusted and adjusted for confounders. RESULTS: Kidney volume was positively associated in adjusted models with eGFR calculated using Schwartz combined (0.64 ml/min diff per unit increase in volume, 95% CI 0.25 to 1.02), Zappitelli (0.79, 95% CI 0.38 to 1.20) and Filler (2.84, 95% CI 1.40 to 4.28). There was an association with the presence of albuminuria but not with its level, or with other urinary markers or with blood pressure. CONCLUSION: Foetal kidney volume was associated with small increases in eGFR in mid-childhood. Longitudinal follow-up to investigate the relationship between kidney volume and markers of kidney function as children go through puberty is required.


Assuntos
Rim , Criança , Humanos , Recém-Nascido , Albuminúria/urina , Biomarcadores , Creatinina , Cistatina C , Taxa de Filtração Glomerular/fisiologia , Rim/anatomia & histologia , Rim/fisiologia , Testes de Função Renal , Tamanho do Órgão
9.
Sensors (Basel) ; 23(22)2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-38005622

RESUMO

Assessment of wastewater effluent quality in terms of physicochemical and microbial parameters is a difficult task; therefore, an online method which combines the variables and represents a final value as the quality index could be used as a useful management tool for decision makers. However, conventional measurement methods often have limitations, such as time-consuming processes and high associated costs, which hinder efficient and practical monitoring. Therefore, this study presents an approach that underscores the importance of using both short- and long-term memory networks (LSTM) to enhance monitoring capabilities within wastewater treatment plants (WWTPs). The use of LSTM networks for soft sensor design is presented as a promising solution for accurate variable estimation to quantify effluent quality using the total chemical oxygen demand (TCOD) quality index. For the realization of this work, we first generated a dataset that describes the behavior of the activated sludge system in discrete time. Then, we developed a deep LSTM network structure as a basis for formulating the LSTM-based soft sensor model. The results demonstrate that this structure produces high-precision predictions for the concentrations of soluble X1 and solid X2 substrates in the wastewater treatment system. After hyperparameter optimization, the predictive capacity of the proposed model is optimized, with average values of performance metrics, mean square error (MSE), coefficient of determination (R2), and mean absolute percentage error (MAPE), of 23.38, 0.97, and 1.31 for X1, and 9.74, 0.93, and 1.89 for X2, respectively. According to the results, the proposed LSTM-based soft sensor can be a valuable tool for determining effluent quality index in wastewater treatment systems.


Assuntos
Memória de Curto Prazo , Purificação da Água , Redes Neurais de Computação , Águas Residuárias , Memória de Longo Prazo
10.
J Neurosci ; 41(22): 4850-4866, 2021 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-33875572

RESUMO

Taste neurons are functionally and molecularly diverse, but their morphologic diversity remains completely unexplored. Using sparse cell genetic labeling, we provide the first reconstructions of peripheral taste neurons. The branching characteristics across 96 taste neurons show surprising diversity in their complexities. Individual neurons had 1-17 separate arbors entering between one and seven taste buds, 18 of these neurons also innervated non-taste epithelia. Axon branching characteristics are similar in gustatory neurons from male and female mice. Cluster analysis separated the neurons into four groups according to branch complexity. The primary difference between clusters was the amount of the nerve fiber within the taste bud available to contact taste-transducing cells. Consistently, we found that the maximum number of taste-transducing cells capable of providing convergent input onto individual gustatory neurons varied with a range of 1-22 taste-transducing cells. Differences in branching characteristics across neurons indicate that some neurons likely receive input from a larger number of taste-transducing cells than other neurons (differential convergence). By dividing neurons into two groups based on the type of taste-transducing cell most contacted, we found that neurons contacting primarily sour transducing cells were more heavily branched than those contacting primarily sweet/bitter/umami transducing cells. This suggests that neuron morphologies may differ across functional taste quality. However, the considerable remaining variability within each group also suggests differential convergence within each functional taste quality. Each possibility has functional implications for the system.SIGNIFICANCE STATEMENT Taste neurons are considered relay cells, communicating information from taste-transducing cells to the brain, without variation in morphology. By reconstructing peripheral taste neuron morphologies for the first time, we found that some peripheral gustatory neurons are simply branched, and can receive input from only a few taste-transducing cells. Other taste neurons are heavily branched, contacting many more taste-transducing cells than simply branched neurons. Based on the type of taste-transducing cell contacted, branching characteristics are predicted to differ across (and within) quality types (sweet/bitter/umami vs sour). Therefore, functional differences between neurons likely depends on the number of taste-transducing cells providing input and not just the type of cell providing input.


Assuntos
Axônios/ultraestrutura , Imageamento Tridimensional , Papilas Gustativas/ultraestrutura , Animais , Processamento de Imagem Assistida por Computador , Camundongos , Microscopia Confocal
11.
Mol Psychiatry ; 26(7): 3512-3523, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-32963336

RESUMO

The heterogeneity of schizophrenia has defied efforts to derive reproducible and definitive anatomical maps of structural brain changes associated with the disorder. We aimed to map deviations from normative ranges of brain structure for individual patients and evaluate whether the loci of individual deviations recapitulated group-average brain maps of schizophrenia pathology. For each of 48 white matter tracts and 68 cortical regions, normative percentiles of variation in fractional anisotropy (FA) and cortical thickness (CT) were established using diffusion-weighted and structural MRI from healthy adults (n = 195). Individuals with schizophrenia (n = 322) were classified as either within the normative range for healthy individuals of the same age and sex (5-95% percentiles), infra-normal (<5% percentile) or supra-normal (>95% percentile). Repeating this classification for each tract and region yielded a deviation map for each individual. Compared to the healthy comparison group, the schizophrenia group showed widespread reductions in FA and CT, involving virtually all white matter tracts and cortical regions. Paradoxically, however, no more than 15-20% of patients deviated from the normative range for any single tract or region. Furthermore, 79% of patients showed infra-normal deviations for at least one locus (healthy individuals: 59 ± 2%, p < 0.001). Thus, while infra-normal deviations were common among patients, their anatomical loci were highly inconsistent between individuals. Higher polygenic risk for schizophrenia associated with a greater number of regions with infra-normal deviations in CT (r = -0.17, p = 0.006). We conclude that anatomical loci of schizophrenia-related changes are highly heterogeneous across individuals to the extent that group-consensus pathological maps are not representative of most individual patients. Normative modeling can aid in parsing schizophrenia heterogeneity and guiding personalized interventions.


Assuntos
Esquizofrenia , Substância Branca , Adulto , Anisotropia , Encéfalo/diagnóstico por imagem , Estudos Transversais , Humanos , Esquizofrenia/diagnóstico por imagem , Esquizofrenia/genética , Substância Branca/diagnóstico por imagem
12.
J Child Psychol Psychiatry ; 63(7): 802-809, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34541665

RESUMO

BACKGROUND: Women are 1.5-3 times more likely to suffer from depression than men. This sex bias first emerges during puberty and then persists across the reproductive years. As the cause remains largely elusive, we performed a methylation-wide association study (MWAS) to generate novel hypotheses. METHODS: We assayed nearly all 28 million possible methylation sites in blood in 595 blood samples from 487 participants aged 9-17. MWASs were performed to identify methylation sites associated with increasing sex differences in depression symptoms as a function of pubertal stage. Epigenetic deconvolution was applied to perform analyses on a cell-type specific level. RESULTS: In monocytes, a substantial number of significant associations were detected after controlling the FDR at 0.05. These results could not be explained by plasma testosterone/estradiol or current/lifetime trauma. Our top results in monocytes were significantly enriched (ratio of 2.48) for genes in the top of a large genome-wide association study (GWAS) meta-analysis of depression and neurodevelopment-related Gene Ontology (GO) terms that remained significant after correcting for multiple testing. Focusing on our most robust findings (70 genes overlapping with the GWAS meta-analysis and the significant GO terms), we find genes coding for members of each of the major classes of axon guidance molecules (netrins, slits, semaphorins, ephrins, and cell adhesion molecules). Many of these genes were previously implicated in rodent studies of brain development and depression-like phenotypes, as well as human methylation, gene expression and GWAS studies. CONCLUSIONS: Our study suggests that the emergence of sex differences in depression may be related to the differential rewiring of brain circuits between boys and girls during puberty.


Assuntos
Estudo de Associação Genômica Ampla , Caracteres Sexuais , Encéfalo , Metilação de DNA , Depressão/genética , Feminino , Humanos , Masculino , Puberdade
13.
Ther Drug Monit ; 44(1): 215-223, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34657093

RESUMO

PURPOSE: Innovative and sustainable sampling strategies for bioanalytical quantification of drugs and metabolites have gained considerable interest. Scavenging can be stratified as a sustainable sampling strategy using residual material because it aligns with the green principles of waste reduction and sampling optimization. Scavenged sampling includes all biological fluids' (eg, blood, liquor, and urine) leftover from standard clinical care. This review elaborates on the past and current landscape of sustainable sampling within therapeutic drug monitoring, with a focus on scavenged sampling. METHODS: In February 2021, 4 databases were searched to assess the literature on the clinical use of innovative and sustainable sampling techniques without applying publication date restrictions. Studies reporting the clinical use of scavenged blood sampling and bridging studies of scavenged sampling and normal blood sampling were eligible for inclusion. RESULTS: Overall, 19 eligible studies concerning scavenged sampling were identified from 1441 records. Scavenged sampling is mainly applied in the pediatric population, although other patient groups may benefit from this strategy. The infrastructure required for scavenged sampling encounters several challenges, including logistic hurdles, storage and handling conditions, and documentation errors. A workflow is proposed with identified opportunities that guide the implementation of scavenged sampling. CONCLUSIONS: This review presents current evidence on the clinical use of scavenged sampling strategies. Scavenged sampling can be a suitable approach for drug quantification to improve dosage regimens, perform pharmacokinetic studies, and explore the value of therapeutic drug monitoring without additional sample collection.


Assuntos
Líquidos Corporais , Monitoramento de Medicamentos , Coleta de Amostras Sanguíneas/métodos , Criança , Monitoramento de Medicamentos/métodos , Humanos , Manejo de Espécimes
14.
Addict Biol ; 27(2): e13114, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34791764

RESUMO

Using an integrative, multi-tissue design, we sought to characterize methylation and hydroxymethylation changes in blood and brain associated with alcohol use disorder (AUD). First, we used epigenomic deconvolution to perform cell-type-specific methylome-wide association studies within subpopulations of granulocytes/T-cells/B-cells/monocytes in 1132 blood samples. Blood findings were then examined for overlap with AUD-related associations with methylation and hydroxymethylation in 50 human post-mortem brain samples. Follow-up analyses investigated if overlapping findings mediated AUD-associated transcription changes in the same brain samples. Lastly, we replicated our blood findings in an independent sample of 412 individuals and aimed to replicate published alcohol methylation findings using our results. Cell-type-specific analyses in blood identified methylome-wide significant associations in monocytes and T-cells. The monocyte findings were significantly enriched for AUD-related methylation and hydroxymethylation in brain. Hydroxymethylation in specific sites mediated AUD-associated transcription in the same brain samples. As part of the most comprehensive methylation study of AUD to date, this work involved the first cell-type-specific methylation study of AUD conducted in blood, identifying and replicating a finding in DLGAP1 that may be a blood-based biomarker of AUD. In this first study to consider the role of hydroxymethylation in AUD, we found evidence for a novel mechanism for cognitive deficits associated with AUD. Our results suggest promising new avenues for AUD research.


Assuntos
Alcoolismo , Consumo de Bebidas Alcoólicas , Alcoolismo/genética , Encéfalo , Metilação de DNA , Epigenoma , Humanos
15.
Hum Brain Mapp ; 42(13): 4155-4172, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33544411

RESUMO

Repetitive transcranial magnetic stimulation (rTMS) of the dorsolateral prefrontal cortex (DLPFC) is an established treatment for refractory depression, however, therapeutic outcomes vary. Mounting evidence suggests that clinical response relates to functional connectivity with the subgenual cingulate cortex (SGC) at the precise DLPFC stimulation site. Critically, SGC-related network architecture shows considerable interindividual variation across the spatial extent of the DLPFC, indicating that connectivity-based target personalization could potentially be necessary to improve treatment outcomes. However, to date accurate personalization has not appeared feasible, with recent work indicating that the intraindividual reproducibility of optimal targets is limited to 3.5 cm. Here we developed reliable and accurate methodologies to compute individualized connectivity-guided stimulation targets. In resting-state functional MRI scans acquired across 1,000 healthy adults, we demonstrate that, using this approach, personalized targets can be reliably and robustly pinpointed, with a median accuracy of ~2 mm between scans repeated across separate days. These targets remained highly stable, even after 1 year, with a median intraindividual distance between coordinates of only 2.7 mm. Interindividual spatial variation in personalized targets exceeded intraindividual variation by a factor of up to 6.85, suggesting that personalized targets did not trivially converge to a group-average site. Moreover, personalized targets were heritable, suggesting that connectivity-guided rTMS personalization is stable over time and under genetic control. This computational framework provides capacity for personalized connectivity-guided TMS targets to be robustly computed with high precision and has the flexibly to advance research in other basic research and clinical applications.


Assuntos
Conectoma/normas , Transtorno Depressivo Resistente a Tratamento/terapia , Córtex Pré-Frontal Dorsolateral , Estimulação Magnética Transcraniana/normas , Adulto , Conectoma/métodos , Transtorno Depressivo Resistente a Tratamento/diagnóstico por imagem , Córtex Pré-Frontal Dorsolateral/diagnóstico por imagem , Estudos de Viabilidade , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Reprodutibilidade dos Testes , Estimulação Magnética Transcraniana/métodos , Adulto Jovem
16.
Osteoporos Int ; 32(2): 225-232, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33128074

RESUMO

INTRODUCTION: Methotrexate (MTX)-related osteopathy is rare, defined by the triad of pain, osteoporosis, and "atypical fractures" when it was first described in the 1970s in children treated with high doses MTX for acute leukemia. Since then, several cases have been reported in patients treated with low-dose MTX for inflammatory diseases. METHODS: A systematic research of cases of MTX-related osteopathy was performed in records of Rheumatology Department of Rennes University Hospital. Data collection focused on demographic data, corticosteroid doses, MTX doses and intake method, cumulative doses, year of diagnosis, fracture location, bone densitometry value, and osteoporosis treatment if necessary. A literature review was also conducted to identify other cases in literature and try to understand the pathophysiological mechanisms of this rare entity. RESULTS: We report 5 cases identified between 2011 and 2019, which represents the largest cohort described excluding oncology cases. Fracture locations were atypical for osteoporotic fractures. All patients improved in the following months with MTX withdrawal. All patients except one were treated with antiresorptives (bisphosphonates, denosumab). Two patients, treated with bisphosphonates, had a recurrence of fracture, once again of atypical location. Twenty-five cases were collected in literature with similar clinical presentation. The cellular studies that investigated the bone toxicity of MTX mainly showed a decrease in the number of osteoblasts, osteocytes, and chondrocytes in the growth plate and an increase in the number and activity of osteoclasts. In vitro, consequences of mechanical stimulation on human trabecular bone cells in the presence of MTX showed an alteration in mechano-transduction, with membrane hyperpolarization, acting on the integrin pathway. In contrast with our report, the cases described in the literature were not consistently associated with a decrease in bone mineral density (BMD). CONCLUSION: MTX osteopathy while rare must be known by the rheumatologist, especially when using this treatment for inflammatory conditions. The mechanisms are still poorly understood, raising the question of a possible remnant effect of MTX on osteo-forming bone cells, potentially dose-dependent. Methotrexate (MTX) osteopathy, described as a clinical triad, pain, osteoporosis, and atypical stress fractures, while rare, must be known by the rheumatologist. Our cohort of 5 cases represent the largest series of the literature. Pathophysiological studies raised the question of a dose-dependent remnant effect of MTX on osteo-forming bone cells.


Assuntos
Antirreumáticos , Artrite Reumatoide , Doenças Ósseas , Osteoporose , Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Densidade Óssea , Criança , Humanos , Metotrexato/efeitos adversos , Osteoporose/induzido quimicamente , Osteoporose/tratamento farmacológico
17.
Osteoporos Int ; 32(9): 1763-1775, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33655400

RESUMO

The purpose of this multicentric study was to evaluate the prevalence and causes of Elevated Bone Mass (EBM) in patients who underwent DXA scanning over a 10-year period. The prevalence of EBM was 1 in 100. The main causes of EBM were degenerative spine disorders and renal osteodystrophy. INTRODUCTION: Reports of elevated bone mass (EBM) on routine dual energy X-Ray absorptiometry (DXA) scanning are not infrequent. However, epidemiological studies of EBM are few and definition thresholds are variable. The purpose of this French multicentric study was to evaluate the prevalence and causes of EBM in adult patients who underwent DXA scanning over a 10-year period. METHODS: This multicentric, retrospective study was conducted in six French regional bone centres. DXA databases were initially searched for individuals with a bone mineral density (BMD) Z-score ≥ +4 at any site in the lumbar spine or hip from April 1st, 2008 to April 30st, 2018. RESULTS: In all, 72,225 patients with at least one DXA scan were identified. Of these, 909 (322 men and 587 women) had a Z-score ≥ + 4, i.e. a prevalence of 1.26% [1.18-1.34%]. The DXA scan reports and imagery and medical records of the 909 EBM patients were reviewed and 936 causes were found. In 42 patients (4%), no cause could be determined due to unavailability of data. Artefactual causes of EBM were found in 752 patients (80%), in whom the predominant cause was degenerative disease of the spine (613 patients, 65%). Acquired causes of focal EBM-including Paget's disease (n = 7)-were found in 12 patients (1%), and acquired causes of generalized EBM-including renal osteodystrophy (n = 32), haematological disorders (n = 20) and hypoparathyroidism (n = 15)-in 84 patients (9%). Other causes were rare hereditary diseases and unknown EBM in 19 (2%) and 27 (3%) cases respectively. CONCLUSIONS: The prevalence of EBM was approximately 1 in 100. These findings suggest that degenerative disease of the spine is the main cause of EBM, but that acquired or hereditary diseases are also causal factors.


Assuntos
Densidade Óssea , Vértebras Lombares , Absorciometria de Fóton , Adulto , Feminino , Humanos , Vértebras Lombares/diagnóstico por imagem , Masculino , Prevalência , Estudos Retrospectivos
18.
Chemistry ; 27(42): 10807-10825, 2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-34032319

RESUMO

The renaissance of Brønsted superbases is primarily based on their pronounced capacity for a large variety of chemical transformations under mild reaction conditions. Four major set screws are available for the selective tuning of the basicity: the nature of the basic center (N, P, …), the degree of electron donation by substituents to the central atom, the possibility of charge delocalization, and the energy gain by hydrogen bonding. Within the past decades, a plethora of neutral electron-rich phosphine and phosphazene bases have appeared in the literature. Their outstanding properties and advantages over inorganic or charged bases have now made them indispensable as auxiliary bases in deprotonation processes. Herein, an update of the chemistry of basic phosphines and phosphazenes is given. In addition, due to widespread interest, their use in catalysis or as ligands in coordination chemistry is highlighted.

19.
Chemistry ; 27(21): 6460-6464, 2021 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-32776547

RESUMO

The reaction of the strong monophosphazene base with the weakly acidic phenol leads to the formation of a phenol-phenolate anion with a moderately strong hydrogen bond. Application of the more powerful tetraphosphazene base (Schwesinger base) renders the isolation of the corresponding salt with a free phenolate anion possible. This compound represents the first species featuring the free phenolate anion [H5 C6 -O]- . The deprotonation of phenol derivatives with tetraphosphazene bases represents a great way for the clean preparation of salts featuring free phenolate anions and in addition allows the selective syntheses of hydrogen bonded phenol-phenolate salts. This work presents a phosphazenium phenolate salt with a redox potential of -0.72 V and its capability for the selective activation of the chemically inert greenhouse gas SF6 . The performed two-electron reduction of SF6 leads to phosphazenium pentafluorosulfanide ([SF5 ]- ) and fluoride salts.

20.
Chemistry ; 27(21): 6465-6478, 2021 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-33368714

RESUMO

In this work, the syntheses of non-coordinated electron-rich phenolate anions via deprotonation of the corresponding alcohols with an extremely powerful perethyl tetraphosphazene base (Schwesinger base) are reported. The application of uncharged phosphazenes renders the selective preparation of anionic phenol-phenolate and phenolate hydrates possible, which allows for the investigation of hydrogen bonding in these species. Hydrogen bonding brings about decreased redox potentials relative to the corresponding non-coordinated phenolate anions. The latter show redox potentials of up to -0.72(1) V vs. SCE, which is comparable to that of zinc metal, thus qualifying their application as organic zinc mimics. We utilized phenolates as reducing agents for the generation of radical anions in addition to the corresponding phenoxyl radicals. A tetracyanoethylene radical anion salt was synthesized and fully characterized as a representative example. We also present the activation of sulfur hexafluoride (SF6 ) with phenolates in a SET reaction, in which the nature of the respective phenolate determines whether simple fluorides or pentafluorosulfanide ([SF5 ]- ) salts are formed.

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