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1.
Mol Ther ; 32(4): 1096-1109, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38291756

RESUMO

Spasticity, affecting ∼75% of patients with spinal cord injury (SCI), leads to hyperreflexia, muscle spasms, and cocontractions of antagonist muscles, greatly affecting their quality of life. Spasticity primarily stems from the hyperexcitability of motoneurons below the lesion, driven by an upregulation of the persistent sodium current and a downregulation of chloride extrusion. This imbalance results from the post-SCI activation of calpain1, which cleaves Nav1.6 channels and KCC2 cotransporters. Our study was focused on mitigating spasticity by specifically targeting calpain1 in spinal motoneurons. We successfully transduced lumbar motoneurons in adult rats with SCI using intrathecal administration of adeno-associated virus vector serotype 6, carrying a shRNA sequence against calpain1. This approach significantly reduced calpain1 expression in transduced motoneurons, leading to a noticeable decrease in spasticity symptoms, including hyperreflexia, muscle spasms, and cocontractions in hindlimb muscles, which are particularly evident in the second month post-SCI. In addition, this decrease, which prevented the escalation of spasticity to a severe grade, paralleled the restoration of KCC2 levels in transduced motoneurons, suggesting a reduced proteolytic activity of calpain1. These findings demonstrate that inhibiting calpain1 in motoneurons is a promising strategy for alleviating spasticity in SCI patients.


Assuntos
Traumatismos da Medula Espinal , Simportadores , Animais , Ratos , Neurônios Motores/metabolismo , Espasticidade Muscular/genética , Espasticidade Muscular/terapia , Qualidade de Vida , Reflexo Anormal , Espasmo/metabolismo , Espasmo/patologia , Medula Espinal/metabolismo , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/genética , Traumatismos da Medula Espinal/terapia , Simportadores/genética
2.
Proc Natl Acad Sci U S A ; 119(21): e2200413119, 2022 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-35576468

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection fatality rate (IFR) doubles with every 5 y of age from childhood onward. Circulating autoantibodies neutralizing IFN-α, IFN-ω, and/or IFN-ß are found in ∼20% of deceased patients across age groups, and in ∼1% of individuals aged <70 y and in >4% of those >70 y old in the general population. With a sample of 1,261 unvaccinated deceased patients and 34,159 individuals of the general population sampled before the pandemic, we estimated both IFR and relative risk of death (RRD) across age groups for individuals carrying autoantibodies neutralizing type I IFNs, relative to noncarriers. The RRD associated with any combination of autoantibodies was higher in subjects under 70 y old. For autoantibodies neutralizing IFN-α2 or IFN-ω, the RRDs were 17.0 (95% CI: 11.7 to 24.7) and 5.8 (4.5 to 7.4) for individuals <70 y and ≥70 y old, respectively, whereas, for autoantibodies neutralizing both molecules, the RRDs were 188.3 (44.8 to 774.4) and 7.2 (5.0 to 10.3), respectively. In contrast, IFRs increased with age, ranging from 0.17% (0.12 to 0.31) for individuals <40 y old to 26.7% (20.3 to 35.2) for those ≥80 y old for autoantibodies neutralizing IFN-α2 or IFN-ω, and from 0.84% (0.31 to 8.28) to 40.5% (27.82 to 61.20) for autoantibodies neutralizing both. Autoantibodies against type I IFNs increase IFRs, and are associated with high RRDs, especially when neutralizing both IFN-α2 and IFN-ω. Remarkably, IFRs increase with age, whereas RRDs decrease with age. Autoimmunity to type I IFNs is a strong and common predictor of COVID-19 death.


Assuntos
Anticorpos Neutralizantes , Autoanticorpos , Autoimunidade , COVID-19 , Interferon Tipo I , SARS-CoV-2 , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Anticorpos Neutralizantes/sangue , Autoanticorpos/sangue , COVID-19/imunologia , COVID-19/mortalidade , Feminino , Humanos , Interferon Tipo I/imunologia , Masculino , Pessoa de Meia-Idade , Risco
3.
J Clin Immunol ; 44(7): 163, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39008214

RESUMO

BACKGROUND: Cryptococcosis is a life-threatening disease caused by Cryptococcus neoformans or C. gattii. Neutralizing autoantibodies (auto-Abs) against granulocyte-macrophage colony-stimulating factor (GM-CSF) in otherwise healthy adults with cryptococcal meningitis have been described since 2013. We searched for neutralizing auto-Abs in sera collected from Colombian patients with non-HIV-associated cryptococcosis in a retrospective national cohort from 1997 to 2016. METHODS: We reviewed clinical and laboratory records and assessed the presence of neutralizing auto-Abs against GM-CSF in 30 HIV negative adults with cryptococcosis (13 caused by C. gattii and 17 caused by C. neoformans). RESULTS: We detected neutralizing auto-Abs against GM-CSF in the sera of 10 out of 13 (77%) patients infected with C. gattii and one out of 17 (6%) patients infected with C. neoformans. CONCLUSIONS: We report eleven Colombian patients diagnosed with cryptococcosis who had auto-Abs that neutralize GM-CSF. Among these patients, ten were infected with C. gattii and only one with C. neoformans.


Assuntos
Anticorpos Neutralizantes , Autoanticorpos , Criptococose , Cryptococcus gattii , Cryptococcus neoformans , Fator Estimulador de Colônias de Granulócitos e Macrófagos , Humanos , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Autoanticorpos/sangue , Autoanticorpos/imunologia , Masculino , Colômbia , Feminino , Adulto , Cryptococcus gattii/imunologia , Pessoa de Meia-Idade , Cryptococcus neoformans/imunologia , Criptococose/imunologia , Criptococose/diagnóstico , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Estudos Retrospectivos , Soronegatividade para HIV/imunologia , Adulto Jovem , Idoso
4.
Am J Bot ; 111(4): e16309, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38584339

RESUMO

PREMISE: Barriers at different reproductive stages contribute to reproductive isolation. Self-incompatibility (SI) systems that prevent self-pollination could also act to control interspecific pollination and contribute to reproductive isolation, preventing hybridization. Here we evaluated whether SI contributes to reproductive isolation among four co-occurring Opuntia species that flower at similar times and may hybridize with each other. METHODS: We assessed whether Opuntia cantabrigiensis, O. robusta, O. streptacantha, and O. tomentosa, were self-compatible and formed hybrid seeds in five manipulation treatments to achieve self-pollination, intraspecific cross-pollination, open pollination (control), interspecific crosses or apomixis, then recorded flowering phenology and synchrony. RESULTS: All species flowered in the spring with a degree of synchrony, so that two pairs of species were predisposed to interspecific pollination (O. cantabrigiensis with O. robusta, O. streptacantha with O. tomentosa). All species had distinct reproductive systems: Opuntia cantabrigiensis is self-incompatible and did not produce hybrid seeds as an interspecific pollen recipient; O. robusta is a dioecious species, which formed a low proportion of hybrid seeds; O. streptacantha and O. tomentosa are self-compatible and produced hybrid seeds. CONCLUSIONS: Opuntia cantabrigiensis had a strong pollen-pistil barrier, likely due to its self-incompatibility. Opuntia robusta, the dioecious species, is an obligate outcrosser and probably partially lost its ability to prevent interspecific pollen germination. Given that the self-compatible species can set hybrid seeds, we conclude that pollen-pistil interaction and high flowering synchrony represent weak barriers; whether reproductive isolation occurs later in their life cycle (e.g., germination or seedling survival) needs to be determined.


Assuntos
Flores , Hibridização Genética , Opuntia , Polinização , Isolamento Reprodutivo , Sementes , Autoincompatibilidade em Angiospermas , Simpatria , Autoincompatibilidade em Angiospermas/fisiologia , Flores/fisiologia , Sementes/fisiologia , Opuntia/fisiologia , Reprodução , Pólen/fisiologia , Especificidade da Espécie , Apomixia/fisiologia
5.
Bioorg Med Chem Lett ; 110: 129879, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38977106

RESUMO

In this study, we synthesized a series of seven benzimidazole derivatives incorporating the structural acidic framework of angiotensin II (Ang II) type 1 receptor (AT1R) antagonists (ARA-II) employing a three-step reaction sequence. The chemical structures were confirmed by 1H NMR, 13C NMR and mass spectral data. Through biosimulation, compounds 1-7 were identified as computational safe hits, thus, best candidates underwent ex vivo testing against two distinct mechanisms implicated in hypertension: antagonism of the Ang II type 1 receptor and the blockade of calcium channel. Molecular docking studies helped to understand at the molecular level the dual vasorelaxant effects with the recognition sites of the AT1R and the L-type calcium channel. In an in vivo spontaneously hypertensive rat model (SHR), intraperitoneally administration of compound 1 at 20 mg/kg resulted in a 25 % reduction in systolic blood pressure, demonstrating both ex vivo vasorelaxant action and in vivo antihypertensive multitarget efficacy. ©2024 Elsevier.


Assuntos
Anti-Hipertensivos , Benzimidazóis , Simulação de Acoplamento Molecular , Ratos Endogâmicos SHR , Benzimidazóis/química , Benzimidazóis/farmacologia , Benzimidazóis/síntese química , Animais , Anti-Hipertensivos/farmacologia , Anti-Hipertensivos/síntese química , Anti-Hipertensivos/química , Ratos , Relação Estrutura-Atividade , Pressão Sanguínea/efeitos dos fármacos , Hipertensão/tratamento farmacológico , Receptor Tipo 1 de Angiotensina/metabolismo , Estrutura Molecular , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Bloqueadores do Receptor Tipo 1 de Angiotensina II/síntese química , Bloqueadores do Receptor Tipo 1 de Angiotensina II/química , Bloqueadores dos Canais de Cálcio/farmacologia , Bloqueadores dos Canais de Cálcio/síntese química , Bloqueadores dos Canais de Cálcio/química , Canais de Cálcio Tipo L/metabolismo
6.
J Chem Inf Model ; 64(4): 1229-1244, 2024 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-38356237

RESUMO

Food chemicals have a fundamental role in our lives, with an extended impact on nutrition, disease prevention, and marked economic implications in the food industry. The number of food chemical compounds in public databases has substantially increased in the past few years, which can be characterized using chemoinformatics approaches. We and other groups explored public food chemical libraries containing up to 26,500 compounds. This study aimed to analyze the chemical contents, diversity, and coverage in the chemical space of food chemicals and additives and, from here on, food components. The approach to food components addressed in this study is a public database with more than 70,000 compounds, including those predicted via omics techniques. It was concluded that food components have distinctive physicochemical properties and constitutional descriptors despite sharing many chemical structures with natural products. Food components, on average, have large molecular weights and several apolar structures with saturated hydrocarbons. Compared to reference databases, food component structures have low scaffold and fingerprint-based diversity and high structural complexity, as measured by the fraction of sp3 carbons. These structural features are associated with a large fraction of macronutrients as lipids. Lipids in food components were decompiled by an analysis of the maximum common substructures. The chemical multiverse representation of food chemicals showed a larger coverage of chemical space than natural products and FDA-approved drugs by using different sets of representations.


Assuntos
Produtos Biológicos , Bases de Dados Factuais , Produtos Biológicos/química , Lipídeos
7.
J Chem Inf Model ; 64(6): 1984-1995, 2024 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-38472094

RESUMO

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) main Protease (Mpro) is an enzyme that cleaves viral polyproteins translated from the viral genome and is critical for viral replication. Mpro is a target for anti-SARS-CoV-2 drug development, and multiple Mpro crystals complexed with competitive inhibitors have been reported. In this study, we aimed to develop an Mpro consensus pharmacophore as a tool to expand the search for inhibitors. We generated a consensus model by aligning and summarizing pharmacophoric points from 152 bioactive conformers of SARS-CoV-2 Mpro inhibitors. Validation against a library of conformers from a subset of ligands showed that our model retrieved poses that reproduced the crystal-binding mode in 77% of the cases. Using models derived from a consensus pharmacophore, we screened >340 million compounds. Pharmacophore-matching and chemoinformatics analyses identified new potential Mpro inhibitors. The candidate compounds were chemically dissimilar to the reference set, and among them, demonstrating the relevance of our model. We evaluated the effect of 16 candidates on Mpro enzymatic activity finding that seven have inhibitory activity. Three compounds (1, 4, and 5) had IC50 values in the midmicromolar range. The Mpro consensus pharmacophore reported herein can be used to identify compounds with improved activity and novel chemical scaffolds against Mpro. The method developed for its generation is provided as an open-access code (https://github.com/AngelRuizMoreno/ConcensusPharmacophore) and can be applied to other pharmacological targets.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Bibliotecas de Moléculas Pequenas/farmacologia , Farmacóforo , Consenso , Proteínas não Estruturais Virais/química , Inibidores de Proteases/farmacologia , Inibidores de Proteases/química , Simulação de Acoplamento Molecular , Antivirais/farmacologia , Antivirais/química
8.
J Neuropsychiatry Clin Neurosci ; 36(1): 63-69, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37667628

RESUMO

OBJECTIVE: The investigators aimed to identify the clinical characteristics of patients with or without delirium and preexisting depression, dementia, both, or neither by using validated tools easily administered in clinical practice. METHODS: In this cross-sectional prospective observational study conducted in Medellín, Colombia, 200 geriatric inpatients were evaluated with the Delirium Diagnostic Tool-Provisional (DDT-Pro), Informant Questionnaire on Cognitive Decline in the Elderly, Hachinski Ischemic Scale, Cornell Scale for Depression in Dementia, and Charlson Comorbidity Index-short form. Delirium motor subtype, mortality, and length of hospital stay were assessed. RESULTS: The study included 134 patients without delirium (67%), 14 with delirium only (7%), 16 with delirium and dementia (8%), 13 with delirium and depression (7%), and 23 with delirium, dementia, and depression (the three Ds) (12%). Prevalence rates of dementia (59%) and depression (55%) among 66 patients with delirium were higher than prevalence rates among patients without delirium (13% and 28%, respectively), suggesting that both conditions are risk factors. Main medical diagnoses, mortality, and dementia type did not differ among groups. Motor subtypes were similar among delirium groups. Patients in the delirium groups, except those in the delirium and depression group, were older than patients without delirium. Medical burden was highest among the patients with delirium and dementia and those with all three conditions. Delirium and dementia were more severe when comorbid with each other. Depression was most severe among patients with delirium and depression. Patients with all three conditions had a longer length of hospital stay than those without delirium. CONCLUSIONS: Using brief tools to detect dementia and depression in conjunction with the DDT-Pro to assess delirium diagnosis and severity is feasible and enables a more in-depth evaluation of elderly hospitalized patients. Because previous longitudinal research suggests that these comorbid conditions influence prognosis following a delirium episode, better identification of the three Ds offers proactive interventional opportunities. Depression is an underrecognized risk factor for delirium.


Assuntos
Delírio , Demência , Humanos , Idoso , Delírio/diagnóstico , Delírio/epidemiologia , Delírio/psicologia , Demência/diagnóstico , Demência/epidemiologia , Demência/psicologia , Pacientes Internados , Estudos Transversais , DDT
9.
J Nat Prod ; 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39269718

RESUMO

Natural products (NPs) are secondary metabolites of natural origin with broad applications across various human activities, particularly the discovery of bioactive compounds. Structural elucidation of new NPs entails significant cost and effort. On the other hand, the dereplication of known compounds is crucial for the early exclusion of irrelevant compounds in contemporary pharmaceutical research. NAPROC-13 stands out as a publicly accessible database, providing structural and 13C NMR spectroscopic information for over 25 000 compounds, rendering it a pivotal resource in natural product (NP) research, favoring open science. This study seeks to quantitatively analyze the chemical content, structural diversity, and chemical space coverage of NPs within NAPROC-13, compared to FDA-approved drugs and a very diverse subset of NPs, UNPD-A. Findings indicated that NPs in NAPROC-13 exhibit properties comparable to those in UNPD-A, albeit showcasing a notably diverse array of structural content, scaffolds, ring systems of pharmaceutical interest, and molecular fragments. NAPROC-13 covers a specific region of the chemical multiverse (a generalization of the chemical space from different chemical representations) regarding physicochemical properties and a region as broad as UNPD-A in terms of the structural features represented by fingerprints.

10.
Sensors (Basel) ; 24(14)2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39066028

RESUMO

This paper presents a deep learning approach for predicting rail corrugation based on on-board rolling-stock vertical acceleration and forward velocity measurements using One-Dimensional Convolutional Neural Networks (CNN-1D). The model's performance is examined in a 1:10 scale railway system at two different forward velocities. During both the training and test stages, the CNN-1D produced results with mean absolute percentage errors of less than 5% for both forward velocities, confirming its ability to reproduce the corrugation profile based on real-time acceleration and forward velocity measurements. Moreover, by using a Gradient-weighted Class Activation Mapping (Grad-CAM) technique, it is shown that the CNN-1D can distinguish various regions, including the transition from damaged to undamaged regions and one-sided or two-sided corrugated regions, while predicting corrugation. In summary, the results of this study reveal the potential of data-driven techniques such as CNN-1D in predicting rails' corrugation using online data from the dynamics of the rolling-stock, which can lead to more reliable and efficient maintenance and repair of railways.

11.
Int J Mol Sci ; 25(17)2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39273608

RESUMO

The coronavirus disease 2019 (COVID-19) survivors are frequently observed to present persistent symptoms constituting what has been called "post-acute COVID-19 syndrome" (PACS) or "long COVID-19". Some clinical risk factors have been identified to be associated with PACS development; however, specific mechanisms responsible for PACS pathology remain unknown. This study investigates clinical, immunological, and metabolomic risk factors associated with post-acute COVID-19 syndrome (PACS) in 51 patients, assessed 7-19 months after acute infection. Among the participants, 62.7% were male and 37.2% were female, with an average age of 47.8 years. At the follow-up, 37.2% met the criteria for PACS, revealing significant differences in immunological and metabolomic profiles at the time of acute infection. Patients with PACS were characterized by elevated levels of mature low-density granulocytes (LDGs), interleukin-8 (IL-8), pyruvate, pseudouridine, and cystine. Baseline multivariate analysis showed increased pyruvate and decreased alpha tocopherol levels. At follow-up, there was a decrease in absolute B lymphocytes and an increase in non-classical monocytes and 3-hydroxyisovaleric acid levels. These findings suggest that specific immunological and metabolomic markers during acute infection can help identify patients at higher risk of developing persistent PACS.


Assuntos
COVID-19 , Síndrome de COVID-19 Pós-Aguda , SARS-CoV-2 , Humanos , Feminino , COVID-19/imunologia , COVID-19/metabolismo , COVID-19/complicações , Masculino , Pessoa de Meia-Idade , Adulto , Fatores de Risco , Biomarcadores , Metabolômica/métodos , Idoso , Metaboloma , Interleucina-8/metabolismo
12.
Environ Monit Assess ; 196(10): 916, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39254906

RESUMO

Soil and water characteristics in micro basins with different land uses/land cover (LULC) can influence riparian vegetation diversity, stream water quality, and benthic diatom diversity. We analyzed 18 streams in the upper part of the La Antigua River basin, México, surrounded by cloud forests, livestock pastures, and coffee plantations. Concentrations of P, C, and N were elevated in the humus of forested streams compared to other land uses. In contrast, cations, ammonium, and total suspended solids (TSS) of water streams were higher in pastures and coffee plantations. These results indicate that LULC affects stream chemistry differently across land uses. Vegetation richness was highest (86-133 spp.) in forest streams and lowest in pastures (46-102), whereas pasture streams had the greatest richness of diatoms (9-24), likely due to higher light and temperatures. Some soil and water characteristics correlated with both true diversity and taxonomic diversity; soil carbon exchange capacity (CEC) correlated with vegetation diversity (r = 0.60), while water temperature correlated negatively (r = - 0.68). Diatom diversity was related to soil aluminum (r = - 0.59), magnesium (r = 0.57), water phosphorus (r = 0.88), and chlorophyll (r = 0.75). These findings suggest that land use affects riparian vegetation, while physical and chemical changes influence diatom diversity in stream water and soil. The lack of correlation between vegetation and diatom diversity indicates that one cannot predict the other. This research is an essential first step in understanding how land use changes impact vegetation and diatom diversity in mountain landscapes, providing valuable insights for environmental monitoring and conservation efforts in tropical cloud forests.


Assuntos
Biodiversidade , Diatomáceas , Monitoramento Ambiental , Florestas , Solo , México , Solo/química , Rios/química , Plantas , Fósforo/análise
13.
J Cell Biochem ; 124(8): 1173-1185, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37357420

RESUMO

Sialyl Lewis X (sLex ) antigen is a fucosylated cell-surface glycan that is normally involved in cell-cell interactions. The enhanced expression of sLex on cell surface glycans, which is attributed to the upregulation of fucosyltransferase 6 (FUT6), has been implicated in facilitating metastasis in human colorectal, lung, prostate, and oral cancers. The role that the upregulated FUT6 plays in the progression of tumor to malignancy, with reduced survival rates, makes it a potential target for anticancer drugs. Unfortunately, the lack of experimental structures for FUT6 has hampered the design and development of its inhibitors. In this study, we used in silico techniques to identify potential FUT6 inhibitors. We first modeled the three-dimensional structure of human FUT6 using AlphaFold. Then, we screened the natural compound libraries from the COCONUT database to sort out potential natural products (NPs) with best affinity toward the FUT6 model. As a result of these simulations, we identified three NPs for which we predicted binding affinities and interaction patterns quite similar to those we calculated for two experimentally tested FUT6 inhibitors, that is, fucose mimetic-1 and a GDP-triazole derived compound. We also performed molecular dynamics (MD) simulations for the FUT6 complexes with identified NPs, to investigate their stability. Analysis of the MD simulations showed that the identified NPs establish stable contacts with FUT6 under dynamics conditions. On these grounds, the three screened compounds appear as promising natural alternatives to experimentally tested FUT6 synthetic inhibitors, with expected comparable binding affinity. This envisages good prospects for future experimental validation toward FUT6 inhibition.


Assuntos
Fucosiltransferases , Neoplasias , Humanos , Masculino , Descoberta de Drogas , Fucosiltransferases/antagonistas & inibidores , Fucosiltransferases/metabolismo , Glicosilação , Antígeno Sialil Lewis X/metabolismo
14.
Emerg Infect Dis ; 29(7): 1443-1446, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37347822

RESUMO

We found serologic evidence of spotted fever group Rickettsia in humans and dogs and typhus group Rickettsia in dogs in Reynosa, Mexico. Our investigation revealed serologic samples reactive to spotted fever group Rickettsia in 5 community members, which highlights a potential rickettsial transmission scenario in this region.


Assuntos
Rickettsia , Rickettsiose do Grupo da Febre Maculosa , Tifo Epidêmico Transmitido por Piolhos , Humanos , Animais , Cães , Rickettsia/genética , México/epidemiologia , Anticorpos Antibacterianos , Rickettsiose do Grupo da Febre Maculosa/diagnóstico , Rickettsiose do Grupo da Febre Maculosa/epidemiologia , Rickettsiose do Grupo da Febre Maculosa/veterinária
15.
J Clin Immunol ; 43(2): 247-270, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36648576

RESUMO

Current practices vary widely regarding the immunological work-up and management of patients affected with defects in thymic development (DTD), which include chromosome 22q11.2 microdeletion syndrome (22q11.2del) and other causes of DiGeorge syndrome (DGS) and coloboma, heart defect, atresia choanae, retardation of growth and development, genital hypoplasia, ear anomalies/deafness (CHARGE) syndrome. Practice variations affect the initial and subsequent assessment of immune function, the terminology used to describe the condition and immune status, the accepted criteria for recommending live vaccines, and how often follow-up is needed based on the degree of immune compromise. The lack of consensus and widely varying practices highlight the need to establish updated immunological clinical practice guidelines. These guideline recommendations provide a comprehensive review for immunologists and other clinicians who manage immune aspects of this group of disorders.


Assuntos
Síndrome CHARGE , Síndrome de DiGeorge , Cardiopatias Congênitas , Humanos , Síndrome de DiGeorge/diagnóstico , Síndrome de DiGeorge/genética , Síndrome de DiGeorge/terapia , Deleção Cromossômica , Cromossomos , Cardiopatias Congênitas/genética
16.
J Clin Immunol ; 43(5): 921-932, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36821021

RESUMO

BACKGROUND: Cryptococcosis is a potentially life-threatening fungal disease caused by encapsulated yeasts of the genus Cryptococcus, mostly C. neoformans or C. gattii. Cryptococcal meningitis is the most frequent clinical manifestation in humans. Neutralizing autoantibodies (auto-Abs) against granulocyte-macrophage colony-stimulating factor (GM-CSF) have recently been discovered in otherwise healthy adult patients with cryptococcal meningitis, mostly caused by C. gattii. We hypothesized that three Colombian patients with cryptococcal meningitis caused by C. neoformans in two of them would carry high plasma levels of neutralizing auto-Abs against GM-CSF. METHODS: We reviewed medical and laboratory records, performed immunological evaluations, and tested for anti-cytokine auto-Abs three previously healthy HIV-negative adults with disseminated cryptococcosis. RESULTS: Peripheral blood leukocyte subset levels and serum immunoglobulin concentrations were within the normal ranges. We detected high levels of neutralizing auto-Abs against GM-CSF in the plasma of all three patients. CONCLUSIONS: We report three Colombian patients with disseminated cryptococcosis associated with neutralizing auto-Abs against GM-CSF. Further studies should evaluate the genetic contribution to anti-GM-CSF autoantibody production and the role of the GM-CSF signaling pathway in the immune response to Cryptococcus spp.


Assuntos
Criptococose , Cryptococcus neoformans , Meningite Criptocócica , Adulto , Humanos , Fator Estimulador de Colônias de Granulócitos e Macrófagos , Meningite Criptocócica/diagnóstico , Autoanticorpos , Colômbia , Criptococose/diagnóstico
17.
Mol Genet Metab ; 139(2): 107581, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37104980

RESUMO

INTRODUCTION: Immunometabolic studies in mice have suggested the importance of oxidative phosphorylation (OXPHOS) in humoral immunity. However, there are important distinctions between murine and human immunity. Furthermore, translational studies on the role of OXPHOS in humoral immunity are nearly absent from the biomedical literature. Children with primary OXPHOS deficiency (i.e., mitochondrial disease, MtD), are an important patient population for demonstrating the functional effects of this bioenergetic defect on humoral immunity. METHODS: To define whether OXPHOS deficiency extended to human B cells, we performed extracellular flux analysis on lymphoblastoid B cell lines from children with MtD and controls (N = 4/group). To expand the immune phenotype of B cell OXPHOS deficiency, we conducted a cross-sectional multiplex serology study of the antibacterial antibody repertoire in children with MtD (N = 16) and controls (N = 16) using phage display and immunoprecipitation sequencing (PhIPseq). The PhIPseq library contained >3000 peptides (i.e., epitopes) covering >40 genera and > 150 species of bacteria that infect humans. RESULTS: B cell lymphoblastoid cell lines from children with MtD displayed depressed baseline oxygen consumption, ATP production and reserve capacity, indicating that OXPHOS deficiency extended to these key cells in humoral immunity. Characterization of the bacterial exposome revealed comparable bacterial species between the two groups, mostly Streptococcus and Staphylococcus. The most common species of bacteria was S. pneumoniae. By interrogating the antibacterial antibody repertoire, we found that children with MtD had less robust antibody fold changes to common epitopes. Furthermore, we also found that children with MtD failed to show a direct relationship between the number of bacterial epitopes recognized and age, unlike controls. OXPHOS deficiency extends to B cells in children with MtD, leading to limitations in the antibacterial antibody repertoire. Furthermore, the timing of bacterial exposures was asynchronous, suggesting different periods of increased exposure or susceptibility. CONCLUSIONS: Overall, the antibacterial humoral response is distinctive in children with MtD, suggesting an important role for OXPHOS in B cell function.


Assuntos
Doenças Mitocondriais , Humanos , Criança , Camundongos , Animais , Epitopos , Estudos Transversais , Doenças Mitocondriais/genética , Fosforilação Oxidativa , Metabolismo Energético
18.
Phys Rev Lett ; 130(11): 118203, 2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-37001087

RESUMO

While most chemical bonds weaken under the action of mechanical force (called slip bond behavior), nature has developed bonds that do the opposite: their lifetime increases as force is applied. While such catch bonds have been studied quite extensively at the single molecule level and in adhesive contacts, recent work has shown that they are also abundantly present as crosslinkers in the actin cytoskeleton. However, their role and the mechanism by which they operate in these networks have remained unclear. Here, we present computer simulations that show how polymer networks crosslinked with either slip or catch bonds respond to mechanical stress. Our results reveal that catch bonding may be required to protect dynamic networks against fracture, in particular for mobile linkers that can diffuse freely after unbinding. While mobile slip bonds lead to networks that are very weak at high stresses, mobile catch bonds accumulate in high stress regions and thereby stabilize cracks, leading to a more ductile fracture behavior. This allows cells to combine structural adaptivity at low stresses with mechanical stability at high stresses.

19.
Phys Rev Lett ; 131(25): 258202, 2023 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-38181345

RESUMO

In situ interfacial rheology and numerical simulations are used to investigate microgel monolayers in a wide range of packing fractions, ζ_{2D}. The heterogeneous particle compressibility determines two flow regimes characterized by distinct master curves. To mimic the microgel architecture and reproduce experiments, an interaction potential combining a soft shoulder with the Hertzian model is introduced. In contrast to bulk conditions, the elastic moduli vary nonmonotonically with ζ_{2D} at the interface, confirming long-sought predictions of reentrant behavior for Hertzian-like systems.

20.
Bull World Health Organ ; 101(8): 522-528, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37529018

RESUMO

Human African trypanosomiasis is a life-threatening parasitic infection transmitted by the tsetse fly in sub-Saharan Africa. The most common form is caused by Trypanosoma brucei gambiense, with humans as the main reservoir. Diagnosis in the field requires microscopic examination performed by specifically trained personnel. After over two decades of sustained efforts, the incidence of the disease is strongly declining, and some historically endemic countries are no longer detecting cases. The World Health Organization (WHO) has targeted the elimination of transmission of gambiense human African trypanosomiasis by 2030, defined as zero autochthonous cases for at least five consecutive years. Endemic countries reaching this goal must maintain dedicated surveillance to detect re-emergence or re-introduction. With this new agenda, new tools are needed for verification of the absence of transmission. WHO has therefore developed a target product profile calling for development of a method for population-level cross-cutting surveillance of T. b. gambiense transmission. The method needs to be performed in national or sub-national reference laboratories, and to test in parallel numerous samples shipped from remote rural areas. Among other characteristics the product profile specifies: (i) a simple specimen collection procedure; (ii) no cold-chain requirement to transfer specimens to reference laboratories; (iii) high sensitivity and specificity; (iv) high-throughput, substantially automatized; (v) low cost per specimen, when analysed in large batches; and (vi) applicable also in animals.


La trypanosomiase humaine africaine est une infection parasitaire potentiellement mortelle transmise par la mouche tsé-tsé en Afrique subsaharienne. La forme la plus répandue est causée par Trypanosoma brucei gambiense, les humains constituant son principal réservoir. Établir un diagnostic sur le terrain nécessite un examen microscopique réalisé par du personnel formé à cet effet. Après plus de deux décennies d'efforts soutenus, l'incidence de la maladie diminue fortement et quelques pays historiquement endémiques ne découvrent plus aucun cas. L'objectif de l'Organisation mondiale de la Santé (OMS) est d'éliminer la transmission de la trypanosomiase humaine africaine à T. b. gambiense d'ici 2030, ce qui correspond à zéro cas autochtone pendant au moins cinq années consécutives. Les pays endémiques qui atteignent cet objectif doivent maintenir une surveillance spécifique afin de détecter toute réémergence ou réintroduction. Ce nouveau programme doit s'accompagner de nouveaux outils servant à vérifier l'absence de transmission. L'OMS a donc élaboré un profil de produit cible pour le développement d'un procédé de surveillance transversale de la transmission de T. b. gambiense à l'échelle de la population. Ce procédé doit être effectué dans des laboratoires de référence nationaux ou infranationaux et tester simultanément de nombreux échantillons envoyés depuis des régions rurales isolées. Ce profil de produit comporte notamment les caractéristiques suivantes: (i) une procédure simple de collecte d'échantillons; (ii) aucune exigence concernant le respect de la chaîne du froid lors du transfert des échantillons vers les laboratoires de référence; (iii) un niveau élevé de sensibilité et de spécificité; (iv) un haut débit, en grande partie automatisé; (v) de faibles coûts par échantillon lors d'analyses en masse; et enfin, (vi) applicable aux animaux également.


La tripanosomiasis humana africana es una infección parasitaria potencialmente mortal transmitida por la mosca tsetsé en el África Subsahariana. El principal reservorio es el ser humano, y la forma más común está causada por Trypanosoma brucei gambiense. El diagnóstico práctico requiere un examen microscópico a cargo de personal con formación específica. Tras más de dos décadas de esfuerzos sostenidos, la incidencia de la enfermedad está disminuyendo considerablemente, y en algunos países históricamente endémicos ya no se detectan casos. La Organización Mundial de la Salud (OMS) se ha fijado como objetivo la eliminación de la transmisión de la tripanosomiasis africana humana gambiense para 2030, es decir, cero casos autóctonos durante al menos cinco años consecutivos. Los países endémicos que alcancen este objetivo deben mantener una vigilancia permanente para detectar la reaparición o reintroducción de la enfermedad. Con esta agenda nueva, se necesitan herramientas nuevas para verificar la ausencia de transmisión. Por consiguiente, la OMS ha elaborado un perfil de producto objetivo en el que se pide el desarrollo de un método para la vigilancia transversal a nivel de población sobre la transmisión de T. b. gambiense. El método debe realizarse en laboratorios de referencia nacionales o subnacionales y analizar en paralelo numerosas muestras enviadas desde regiones rurales remotas. Entre otras características, el perfil del producto detalla: (i) un procedimiento sencillo de recogida de muestras; (ii) ningún requisito de cadena de frío para transferir las muestras a los laboratorios de referencia; (iii) alta sensibilidad y especificidad; (iv) alto rendimiento, sustancialmente automatizado; (v) bajo coste por muestra, cuando se analizan en grandes lotes; y (vi) aplicable también en animales.


Assuntos
Tripanossomíase Africana , Moscas Tsé-Tsé , Animais , Humanos , Trypanosoma brucei gambiense , Tripanossomíase Africana/diagnóstico , Tripanossomíase Africana/epidemiologia , Tripanossomíase Africana/parasitologia , Moscas Tsé-Tsé/parasitologia , África Subsaariana , Incidência
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