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1.
Cell ; 179(7): 1661-1676.e19, 2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31835038

RESUMO

Reliable detection of disseminated tumor cells and of the biodistribution of tumor-targeting therapeutic antibodies within the entire body has long been needed to better understand and treat cancer metastasis. Here, we developed an integrated pipeline for automated quantification of cancer metastases and therapeutic antibody targeting, named DeepMACT. First, we enhanced the fluorescent signal of cancer cells more than 100-fold by applying the vDISCO method to image metastasis in transparent mice. Second, we developed deep learning algorithms for automated quantification of metastases with an accuracy matching human expert manual annotation. Deep learning-based quantification in 5 different metastatic cancer models including breast, lung, and pancreatic cancer with distinct organotropisms allowed us to systematically analyze features such as size, shape, spatial distribution, and the degree to which metastases are targeted by a therapeutic monoclonal antibody in entire mice. DeepMACT can thus considerably improve the discovery of effective antibody-based therapeutics at the pre-clinical stage. VIDEO ABSTRACT.


Assuntos
Anticorpos/uso terapêutico , Aprendizado Profundo , Diagnóstico por Computador/métodos , Quimioterapia Assistida por Computador/métodos , Neoplasias/patologia , Animais , Humanos , Células MCF-7 , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , Camundongos SCID , Metástase Neoplásica , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Software , Microambiente Tumoral
2.
Nature ; 603(7901): 464-469, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35264793

RESUMO

The brain generates complex sequences of movements that can be flexibly configured based on behavioural context or real-time sensory feedback1, but how this occurs is not fully understood. Here we developed a 'sequence licking' task in which mice directed their tongue to a target that moved through a series of locations. Mice could rapidly branch the sequence online based on tactile feedback. Closed-loop optogenetics and electrophysiology revealed that the tongue and jaw regions of the primary somatosensory (S1TJ) and motor (M1TJ) cortices2 encoded and controlled tongue kinematics at the level of individual licks. By contrast, the tongue 'premotor' (anterolateral motor) cortex3-10 encoded latent variables including intended lick angle, sequence identity and progress towards the reward that marked successful sequence execution. Movement-nonspecific sequence branching signals occurred in the anterolateral motor cortex and M1TJ. Our results reveal a set of key cortical areas for flexible and context-informed sequence generation.


Assuntos
Córtex Motor , Movimento , Animais , Camundongos , Córtex Motor/fisiologia , Movimento/fisiologia , Optogenética , Córtex Somatossensorial/fisiologia , Língua/fisiologia , Tato
3.
Proc Natl Acad Sci U S A ; 121(13): e2309994121, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38517976

RESUMO

Maternal immunoglobulins of the class G (IgGs) protect offspring from enteric infection, but when, where, and how these antibodies are physiologically generated and confer protection remains enigmatic. We found that circulating IgGs in adult mice preferentially bind early-life gut commensal bacteria over their own adult gut commensal bacteria. IgG-secreting plasma cells specific for early-life gut bacteria appear in the intestine soon after weaning, where they remain into adulthood. Manipulating exposure to gut bacteria or plasma cell development before, but not after, weaning reduced IgG-secreting plasma cells targeting early-life gut bacteria throughout life. Further, the development of this anti-gut commensal IgG response coincides with the early-life interval in which goblet cell-associated antigen passages (GAPs) are present in the colon. Offspring of dams "perturbed" by B cell ablation or reduced bacterial exposure in early life were more susceptible to enteric pathogen challenge. In contrast to current concepts, protective maternal IgGs targeted translocating gut commensals in the offspring, not the enteric pathogen. These early-life events affecting anti-commensal IgG production have intergenerational effects for protection of the offspring.


Assuntos
Linfócitos B , Bactérias , Animais , Camundongos , Bactérias/metabolismo , Células Caliciformes/metabolismo , Imunoglobulina G
4.
Proc Natl Acad Sci U S A ; 119(26): e2202912119, 2022 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-35727967

RESUMO

VEGF was initially discovered due to its angiogenic activity and therefore named "vascular endothelial growth factor." However, its more recently discovered neurotrophic activity may be evolutionarily more ancient. Our previous work showed that all the changes produced by axotomy on the firing activity and synaptic inputs of abducens motoneurons were completely restored after VEGF administration. Therefore, we hypothesized that the lack of VEGF delivered by retrograde transport from the periphery should also affect the physiology of otherwise intact abducens motoneurons. For VEGF retrograde blockade, we chronically applied a neutralizing VEGF antibody to the lateral rectus muscle. Recordings of extracellular single-unit activity and eye movements were made in alert cats before and after the application of the neutralizing antibody. Our data revealed that intact, noninjured abducens motoneurons retrogradely deprived of VEGF exhibited noticeable changes in their firing pattern. There is a general decrease in firing rate and a significant reduction in eye position and eye velocity sensitivity (i.e., a decrease in the tonic and phasic components of their discharge, respectively). Moreover, by means of confocal immunocytochemistry, motoneurons under VEGF blockade showed a marked reduction in the density of afferent synaptic terminals contacting with their cell bodies. Altogether, the present findings demonstrate that the lack of retrogradely delivered VEGF renders abducens motoneurons into an axotomy-like state. This indicates that VEGF is an essential retrograde factor for motoneuronal synaptic drive and discharge activity.


Assuntos
Movimentos Oculares , Neurônios Motores , Terminações Pré-Sinápticas , Fator A de Crescimento do Endotélio Vascular , Animais , Anticorpos Neutralizantes , Axotomia , Gatos , Movimentos Oculares/efeitos dos fármacos , Movimentos Oculares/fisiologia , Neurônios Motores/efeitos dos fármacos , Neurônios Motores/fisiologia , Músculos Oculomotores/efeitos dos fármacos , Músculos Oculomotores/fisiologia , Terminações Pré-Sinápticas/efeitos dos fármacos , Terminações Pré-Sinápticas/fisiologia , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/farmacologia , Fator A de Crescimento do Endotélio Vascular/fisiologia
5.
Proc Natl Acad Sci U S A ; 119(49): e2212155119, 2022 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-36442090

RESUMO

Jasmonates are phytohormones that regulate defense and developmental processes in land plants. Despite the chemical diversity of jasmonate ligands in different plant lineages, they are all perceived by COI1/JAZ co-receptor complexes, in which the hormone acts as a molecular glue between the COI1 F-box and a JAZ repressor. It has been shown that COI1 determines ligand specificity based on the receptor crystal structure and the identification of a single COI1 residue, which is responsible for the evolutionary switch in ligand binding. In this work, we show that JAZ proteins contribute to ligand specificity together with COI1. We propose that specific features of JAZ proteins, which are conserved in bryophytes and lycophytes, enable perception of dn-OPDA ligands regardless the size of the COI1 binding pocket. In vascular plant lineages beyond lycophytes, JAZ evolved to limit binding to JA-Ile, thus impeding dn-OPDA recognition by COI1.


Assuntos
Oxilipinas , Reguladores de Crescimento de Plantas , Ligantes
6.
Proc Natl Acad Sci U S A ; 119(36): e2202930119, 2022 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-36037336

RESUMO

In plants, jasmonate signaling regulates a wide range of processes from growth and development to defense responses and thermotolerance. Jasmonates, such as jasmonic acid (JA), (+)-7-iso-jasmonoyl-l-isoleucine (JA-Ile), 12-oxo-10,15(Z)-phytodienoic acid (OPDA), and dinor-12-oxo-10,15(Z)-phytodienoic acid (dn-OPDA), are derived from C18 (18 Carbon atoms) and C16 polyunsaturated fatty acids (PUFAs), which are found ubiquitously in the plant kingdom. Bryophytes are also rich in C20 and C22 long-chain polyunsaturated fatty acids (LCPUFAs), which are found only at low levels in some vascular plants but are abundant in organisms of other kingdoms, including animals. The existence of bioactive jasmonates derived from LCPUFAs is currently unknown. Here, we describe the identification of an OPDA-like molecule derived from a C20 fatty acid (FA) in the liverwort Marchantia polymorpha (Mp), which we term (5Z,8Z)-10-(4-oxo-5-((Z)-pent-2-en-1-yl)cyclopent-2-en-1-yl)deca-5,8-dienoic acid (C20-OPDA). This molecule accumulates upon wounding and, when applied exogenously, can activate known Coronatine Insensitive 1 (COI1) -dependent and -independent jasmonate responses. Furthermore, we identify a dn-OPDA-like molecule (Δ4-dn-OPDA) deriving from C20-OPDA and demonstrate it to be a ligand of the jasmonate coreceptor (MpCOI1-Mp Jasmonate-Zinc finger inflorescence meristem domain [MpJAZ]) in Marchantia. By analyzing mutants impaired in the production of LCPUFAs, we elucidate the major biosynthetic pathway of C20-OPDA and Δ4-dn-OPDA. Moreover, using a double mutant compromised in the production of both Δ4-dn-OPDA and dn-OPDA, we demonstrate the additive nature of these molecules in the activation of jasmonate responses. Taken together, our data identify a ligand of MpCOI1 and demonstrate LCPUFAs as a source of bioactive jasmonates that are essential to the immune response of M. polymorpha.


Assuntos
Marchantia , Oxilipinas , Ciclopentanos/metabolismo , Ácidos Graxos Insaturados/metabolismo , Ligantes , Marchantia/química , Marchantia/genética , Mutação , Oxilipinas/metabolismo
7.
J Am Chem Soc ; 146(34): 23955-23962, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39137318

RESUMO

The newly discovered series of layered monophosphate tungsten bronzes (L-MPTB) [Ba(PO4)2]WmO3m-3 consist of m-layer-thick slabs of WO6 octahedra separated by barium-phosphate spacers. They display a 2D metallic behavior confined in the central part of the perovskite slabs. Here, we report the missing m = 2 member of this series, containing the rather uncommon W5+ oxidation state. We have analyzed its structure-property relationships in relation to the other members of the L-MPTB family. In particular, we have determined its crystal structure by means of single-crystal X-ray and electron diffraction and investigated its physical properties from resistivity, Seebeck-coefficient and heat-capacity measurements combined with first-principles calculations. All the L-MPTB compounds show metallic behavior down to 1.8 K without any clear charge-density-wave (CDW) order. The m = 2 member, however, displays an increased influence of the spacer that translates into anisotropic negative thermal expansion, reversed thermopower and reversed crystal-field splitting of the tungsten t2g orbitals. Our analysis of the full [Ba(PO4)2]WmO3m-3 series reveals a systematic and significant W off-centering in their octahedral coordination. We identify the resulting anti-polar character of these W displacements as the crucial aspect behind the 2D metallicity of these systems: It leads to the presence of bound charges whose screening determines the distribution of mobile charges, tending to accumulate at the center of the [WmO3-m] block. We argue that this mechanism is analogous to enhanced conductivity observed for charged domain walls in ferroelectrics, thus providing a general design rule to promote 2D metallicity in layered systems.

8.
Brief Bioinform ; 23(3)2022 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-35443054

RESUMO

The identification of the protein fold class is a challenging problem in structural biology. Recent computational methods for fold prediction leverage deep learning techniques to extract protein fold-representative embeddings mainly using evolutionary information in the form of multiple sequence alignment (MSA) as input source. In contrast, protein language models (LM) have reshaped the field thanks to their ability to learn efficient protein representations (protein-LM embeddings) from purely sequential information in a self-supervised manner. In this paper, we analyze a framework for protein fold prediction using pre-trained protein-LM embeddings as input to several fine-tuning neural network models, which are supervisedly trained with fold labels. In particular, we compare the performance of six protein-LM embeddings: the long short-term memory-based UniRep and SeqVec, and the transformer-based ESM-1b, ESM-MSA, ProtBERT and ProtT5; as well as three neural networks: Multi-Layer Perceptron, ResCNN-BGRU (RBG) and Light-Attention (LAT). We separately evaluated the pairwise fold recognition (PFR) and direct fold classification (DFC) tasks on well-known benchmark datasets. The results indicate that the combination of transformer-based embeddings, particularly those obtained at amino acid level, with the RBG and LAT fine-tuning models performs remarkably well in both tasks. To further increase prediction accuracy, we propose several ensemble strategies for PFR and DFC, which provide a significant performance boost over the current state-of-the-art results. All this suggests that moving from traditional protein representations to protein-LM embeddings is a very promising approach to protein fold-related tasks.


Assuntos
Idioma , Redes Neurais de Computação , Processamento de Linguagem Natural , Proteínas/química
9.
Appl Environ Microbiol ; 90(7): e0052824, 2024 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-38916293

RESUMO

Xenorhabdus nematophila is a symbiotic Gammaproteobacterium that produces diverse natural products that facilitate mutualistic and pathogenic interactions in their nematode and insect hosts, respectively. The interplay between X. nematophila secondary metabolism and symbiosis stage is tuned by various global regulators. An example of such a regulator is the LysR-type protein transcription factor LrhA, which regulates amino acid metabolism and is necessary for virulence in insects and normal nematode progeny production. Here, we utilized comparative metabolomics and molecular networking to identify small molecule factors regulated by LrhA and characterized a rare γ-ketoacid (GKA) and two new N-acyl amides, GKA-Arg (1) and GKA-Pro (2) which harbor a γ-keto acyl appendage. A lrhA null mutant produced elevated levels of compound 1 and reduced levels of compound 2 relative to wild type. N-acyl amides 1 and 2 were shown to be selective agonists for the human G-protein-coupled receptors (GPCRs) C3AR1 and CHRM2, respectively. The CHRM2 agonist 2 deleteriously affected the hatch rate and length of Steinernema nematodes. This work further highlights the utility of exploiting regulators of host-bacteria interactions for the identification of the bioactive small molecule signals that they control. IMPORTANCE: Xenorhabdus bacteria are of interest due to their symbiotic relationship with Steinernema nematodes and their ability to produce a variety of natural bioactive compounds. Despite their importance, the regulatory hierarchy connecting specific natural products and their regulators is poorly understood. In this study, comparative metabolomic profiling was utilized to identify the secondary metabolites modulated by the X. nematophila global regulator LrhA. This analysis led to the discovery of three metabolites, including an N-acyl amide that inhibited the egg hatching rate and length of Steinernema carpocapsae nematodes. These findings support the notion that X. nematophila LrhA influences the symbiosis between X. nematophila and S. carpocapsae through N-acyl amide signaling. A deeper understanding of the regulatory hierarchy of these natural products could contribute to a better comprehension of the symbiotic relationship between X. nematophila and S. carpocapsae.


Assuntos
Amidas , Proteínas de Bactérias , Simbiose , Fatores de Transcrição , Xenorhabdus , Xenorhabdus/genética , Xenorhabdus/metabolismo , Xenorhabdus/fisiologia , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Amidas/farmacologia , Amidas/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Regulação Bacteriana da Expressão Gênica , Humanos , Nematoides/microbiologia
10.
New Phytol ; 244(3): 870-882, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38725409

RESUMO

In angiosperms, wound-derived signals travel through the vasculature to systemically activate defence responses throughout the plant. In Arabidopsis thaliana, activity of vasculature-specific Clade 3 glutamate receptor-like (GLR) channels is required for the transmission of electrical signals and cytosolic Ca2+ ([Ca2+]cyt) waves from wounded leaves to distal tissues, triggering activation of oxylipin-dependent defences. Whether nonvascular plants mount systemic responses upon wounding remains unknown. To explore the evolution of systemic defence responses, we investigated electrical and calcium signalling in the nonvascular plant Marchantia polymorpha. We found that electrical signals and [Ca2+]cyt waves are generated in response to mechanical wounding and propagated to nondamaged distal tissues in M. polymorpha. Functional analysis of MpGLR, the only GLR encoded in the genome of M. polymorpha, indicates that its activity is necessary for the systemic transmission of wound-induced electrical signals and [Ca2+]cyt waves, similar to vascular plants. However, spread of these signals is neither coupled to systemic accumulation of oxylipins nor to a transcriptional defence response in the distal tissues of wounded M. polymorpha plants. Our results suggest that lack of vasculature prevents translocation of additional signalling factors that, together with electrical signals and [Ca2+]cyt waves, contribute to systemic activation of defences in tracheophytes.


Assuntos
Sinalização do Cálcio , Cálcio , Regulação da Expressão Gênica de Plantas , Marchantia , Oxilipinas , Marchantia/genética , Marchantia/fisiologia , Oxilipinas/metabolismo , Cálcio/metabolismo , Receptores de Glutamato/metabolismo , Receptores de Glutamato/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Folhas de Planta/metabolismo , Folhas de Planta/genética
11.
Artigo em Inglês | MEDLINE | ID: mdl-39400561

RESUMO

OBJECTIVE: Identification of those at high and low risk of disease relapse is a major unmet need in the management of patients with ANCA-associated vasculitis (AAV). Precise stratification would allow tailoring of immunosuppressive medication. We profiled the autoantibody repertoire of AAV patients in remission to identify novel autoantibodies associated with relapse risk. METHODS: Plasma samples collected from 246 AAV patients in remission were screened for novel autoantibodies using in-house generated protein arrays including 42 000 protein fragments representing 18 000 unique human proteins. Patients were categorized based on the occurrence and frequency of relapses. We modelled the association between these antibodies and relapse occurrence using descriptive and high dimensional regression approaches. RESULTS: We observed nine autoantibodies at higher frequency in samples from AAV patients experiencing multiple relapses compared with patients in long-term remission off therapy (LTROT). LASSO analysis identified six autoantibodies that exhibited an association with relapse occurrence after sample collection. Antibodies targeting HFE and SYT5 were identified as associated with relapse in both analyses. CONCLUSION: Through a broad protein array-based autoantibody screening, we identified two novel autoantibodies directed against HFE and SYT5 as candidate biomarkers of relapse in AAV.

12.
Plant Cell Environ ; 47(7): 2336-2350, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38500380

RESUMO

Chloroplast function is essential for growth, development, and plant adaptation to stress. Organelle stress and plant defence responses were examined here using noxy8 (nonresponding to oxylipins 8) from a series of Arabidopsis mutants. The noxy8 mutation was located at the CLPC2 gene, encoding a chloroplast chaperone of the protease complex CLP. Although its CLPC1 paralogue is considered to generate redundancy, our data reveal significant differences distinguishing CLPC2 and CLPC1 functions. As such, clpc1 mutants displayed a major defect in housekeeping chloroplast proteostasis, leading to a pronounced reduction in growth and pigment levels, enhanced accumulation of chloroplast and cytosol chaperones, and resistance to fosmidomycin. Conversely, clpc2 mutants showed severe susceptibility to lincomycin inhibition of chloroplast translation and resistance to Antimycin A inhibition of mitochondrial respiration. In the response to Pseudomonas syringae pv. tomato, clpc2 but not clpc1 mutants were resistant to bacterial infection, showing higher salicylic acid levels, defence gene expression and 9-LOX pathway activation. Our findings suggest CLPC2 and CLPC1 functional specificity, with a preferential involvement of CLPC1 in housekeeping processes and of CLPC2 in stress responses.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteínas de Cloroplastos , Cloroplastos , Regulação da Expressão Gênica de Plantas , Proteínas de Choque Térmico , Mutação , Estresse Fisiológico , Arabidopsis/genética , Arabidopsis/fisiologia , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Cloroplastos/metabolismo , Proteínas de Cloroplastos/genética , Cloroplastos/metabolismo , Lincomicina/farmacologia , Chaperonas Moleculares/metabolismo , Chaperonas Moleculares/genética , Doenças das Plantas/microbiologia , Pseudomonas syringae/fisiologia , Ácido Salicílico/metabolismo , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo
13.
J Exp Bot ; 75(11): 3557-3578, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38465958

RESUMO

Modern crops exhibit diverse sensitivities to ammonium as the primary nitrogen source, influenced by environmental factors such as external pH and nutrient availability. Despite its significance, there is currently no systematic classification of plant species based on their ammonium sensitivity. We conducted a meta-analysis of 50 plant species and present a new classification method based on the comparison of fresh biomass obtained under ammonium and nitrate nutrition. The classification uses the natural logarithm of the biomass ratio as the size effect indicator of ammonium sensitivity. This numerical parameter is associated with critical factors for nitrogen demand and form preference, such as Ellenberg indicators and the repertoire of nitrogen transporters for ammonium and nitrate uptake. Finally, a comparative analysis of the developmental and metabolic responses, including hormonal balance, is conducted in two species with divergent ammonium sensitivity values in the classification. Results indicate that nitrate has a key role in counteracting ammonium toxicity in species with a higher abundance of genes encoding NRT2-type proteins and fewer of those encoding the AMT2-type proteins. Additionally, the study demonstrates the reliability of the phytohormone balance and methylglyoxal content as indicators for anticipating ammonium toxicity.


Assuntos
Compostos de Amônio , Nitrogênio , Nitrogênio/metabolismo , Concentração de Íons de Hidrogênio , Compostos de Amônio/metabolismo , Nitratos/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Plantas/metabolismo , Adaptação Fisiológica
14.
Psychol Med ; 54(3): 620-630, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37667630

RESUMO

BACKGROUND: The coronavirus disease 2019 (COVID-19) has serious physiological and psychological consequences. The long-term (>12 weeks post-infection) impact of COVID-19 on mental health, specifically in older adults, is unclear. We longitudinally assessed the association of COVID-19 with depression symptomatology in community-dwelling older adults with metabolic syndrome within the framework of the PREDIMED-Plus cohort. METHODS: Participants (n = 5486) aged 55-75 years were included in this longitudinal cohort. COVID-19 status (positive/negative) determined by tests (e.g. polymerase chain reaction severe acute respiratory syndrome coronavirus 2, IgG) was confirmed via event adjudication (410 cases). Pre- and post-COVID-19 depressive symptomatology was ascertained from annual assessments conducted using a validated 21-item Spanish Beck Depression Inventory-II (BDI-II). Multivariable linear and logistic regression models assessed the association between COVID-19 and depression symptomatology. RESULTS: COVID-19 in older adults was associated with higher post-COVID-19 BDI-II scores measured at a median (interquartile range) of 29 (15-40) weeks post-infection [fully adjusted ß = 0.65 points, 95% confidence interval (CI) 0.15-1.15; p = 0.011]. This association was particularly prominent in women (ß = 1.38 points, 95% CI 0.44-2.33, p = 0.004). COVID-19 was associated with 62% increased odds of elevated depression risk (BDI-II ≥ 14) post-COVID-19 when adjusted for confounders (odds ratio; 95% CI 1.13-2.30, p = 0.008). CONCLUSIONS: COVID-19 was associated with long-term depression risk in older adults with overweight/obesity and metabolic syndrome, particularly in women. Thus, long-term evaluations of the impact of COVID-19 on mental health and preventive public health initiatives are warranted in older adults.


Assuntos
COVID-19 , Síndrome Metabólica , Humanos , Feminino , Idoso , COVID-19/epidemiologia , Depressão/psicologia , Síndrome Metabólica/epidemiologia , Sobrepeso/epidemiologia , Obesidade/epidemiologia
15.
Exp Physiol ; 109(1): 17-26, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-36869596

RESUMO

Proprioception is the sense that lets us perceive the location, movement and action of the body parts. The proprioceptive apparatus includes specialized sense organs (proprioceptors) which are embedded in the skeletal muscles. The eyeballs are moved by six pairs of eye muscles and binocular vision depends on fine-tuned coordination of the optical axes of both eyes. Although experimental studies indicate that the brain has access to eye position information, both classical proprioceptors (muscle spindles and Golgi tendon organ) are absent in the extraocular muscles of most mammalian species. This paradox of monitoring extraocular muscle activity in the absence of typical proprioceptors seemed to be resolved when a particular nerve specialization (the palisade ending) was detected in the extraocular muscles of mammals. In fact, for decades there was consensus that palisade endings were sensory structures that provide eye position information. The sensory function was called into question when recent studies revealed the molecular phenotype and the origin of palisade endings. Today we are faced with the fact that palisade endings exhibit sensory as well as motor features. This review aims to evaluate the literature on extraocular muscle proprioceptors and palisade endings and to reconsider current knowledge of their structure and function.


Assuntos
Músculos Oculomotores , Células Receptoras Sensoriais , Animais , Músculos Oculomotores/inervação , Músculos Oculomotores/fisiologia , Mecanorreceptores , Propriocepção/fisiologia , Fusos Musculares , Mamíferos
16.
Nephrol Dial Transplant ; 39(8): 1288-1298, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-38178635

RESUMO

BACKGROUND: Autosomal dominant Alport Syndrome (ADAS), also known as thin basement membrane disease (TBMD), is caused by pathogenic variants in the COL4A3 and COL4A4 genes. A cystic phenotype has been described in some patients with TBMD, but no genetic studies have been performed. We conducted a genetic and radiologic investigation in a cohort of ADAS patients to analyze the prevalence of multicystic kidney disease (MKD) and its association with chronic kidney disease (CKD). METHODS: This was a retrospective single-center cohort study. Thirty-one patients showing pathogenic or likely pathogenic variants in COL4A3 or COL4A4 from a cohort of 79 patients with persistent microscopic hematuria were included. Mean follow-up was 9.4 ± 9.6 years. The primary objective of the study was to determine the prevalence of MKD in the cohort of ADAS patients. Secondary objectives were to determine risk factors associated with an estimated glomerular filtration rate (eGFR) <45 mL/min/1.73 m2 at the time of genetic and radiologic evaluation and to investigate the coexistence of other genetic abnormalities associated with familial hematuria and cystic kidney disease. RESULTS: MKD was found in 16 patients (52%). Mean number of cysts per kidney was 12.7 ± 5.5. No genetic abnormalities were found in a panel of 101 other genes related to familial hematuria, focal segmental glomerulosclerosis and cystic kidney disease. A greater number of patients with MKD had an eGFR <45 mL/min/1.73 m2 (63% vs 7%, P = .006) and more advanced CKD than patients without MKD. The annual rate of eGFR decline was greater in patients with MKD: -1.8 vs 0.06 mL/min/1.73 m2/year (P = .009). By multivariable linear regression analysis, the main determinants of eGFR change per year were time-averaged proteinuria (P = .002) and MKD (P = .02). CONCLUSION: MKD is commonly found in ADAS and is associated with a worse kidney outcome. No pathogenic variants were found in genes other than COL4A3/COL4A4.


Assuntos
Colágeno Tipo IV , Taxa de Filtração Glomerular , Nefrite Hereditária , Fenótipo , Insuficiência Renal Crônica , Humanos , Nefrite Hereditária/genética , Nefrite Hereditária/complicações , Feminino , Masculino , Estudos Retrospectivos , Adulto , Insuficiência Renal Crônica/genética , Insuficiência Renal Crônica/etiologia , Insuficiência Renal Crônica/epidemiologia , Colágeno Tipo IV/genética , Seguimentos , Pessoa de Meia-Idade , Autoantígenos/genética , Prognóstico , Doenças Renais Císticas/genética , Doenças Renais Císticas/epidemiologia , Doenças Renais Císticas/complicações , Prevalência
17.
MMWR Morb Mortal Wkly Rep ; 73(11): 239-244, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38512795

RESUMO

Coccidioidomycosis, histoplasmosis, and blastomycosis are lower respiratory tract fungal infections whose signs and symptoms can resemble those of other respiratory illnesses, including pneumonia caused by bacterial or viral etiologies; this overlap in clinical presentation might lead to missed or delayed diagnoses. The causative fungi live in the environment, often in soil or plant matter. To describe the epidemiologic characteristics of cases of coccidioidomycosis, histoplasmosis, and blastomycosis during the COVID-19 pandemic, CDC analyzed case surveillance data for 2019-2021. During this period, a total of 59,655 coccidioidomycosis cases, 3,595 histoplasmosis cases, and 719 blastomycosis cases were reported to CDC. In 2020, fewer cases of each disease occurred in spring compared with other seasons, and most cases occurred in fall; national seasonality is not typically observed, and cases were seasonally distributed more evenly in 2019 and 2021. Fewer cases coinciding with the start of the COVID-19 pandemic, along with an unusually high blastomycosis case fatality rate in 2021 (17% compared with more typical rates of 8%-10%), suggest that the pandemic might have affected patients' health care-seeking behavior, public health reporting practices, or clinical management of these diseases. Increased awareness and education are needed to encourage health care providers to consider fungal diseases and to identify pneumonia of fungal etiology. Standardized diagnostic guidance and informational resources for fungal testing could be incorporated into broader respiratory disease awareness and preparedness efforts to improve early diagnosis of coccidioidomycosis, histoplasmosis, and blastomycosis.


Assuntos
Blastomicose , COVID-19 , Coccidioidomicose , Histoplasmose , Infecções Respiratórias , Humanos , Estados Unidos/epidemiologia , Blastomicose/epidemiologia , Histoplasmose/diagnóstico , Histoplasmose/epidemiologia , Histoplasmose/microbiologia , Coccidioidomicose/diagnóstico , Coccidioidomicose/epidemiologia , Pandemias , COVID-19/epidemiologia , Infecções Respiratórias/epidemiologia
18.
Inorg Chem ; 63(23): 10471-10480, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38787770

RESUMO

Two quaternary manganese selenites, A2(Mn2O)(SeO3)3 (A = K, Rb), have been synthesized by hydrothermal reactions. They both crystallize in a complex triclinic (P-1) structure built of Jahn-Teller (JT) distorted Mn3+O4+2 octahedra, connected into nearly isosceles [Mn3O14] triangles, themselves arranged into so-called "sawtooth (ST) chains". The K and Rb compounds show subtle variations in the orientations of the MnO4 planes inside the elementary triangles. The ST chains are structurally and magnetically isolated by SeO3 groups and alkali cations. In the ST chains, predominant ferromagnetic interactions were calculated and verified experimentally, which finally order antiferromagnetically between the chains around TN ≈ 22 K. The spin exchanges calculated by DFT + U and fitted by Monte Carlo simulations allow for the quantification of an effective "overall" model. The specific role of the µ3-O bridge on the ferromagnetic (FM) exchanges is discussed, together with spin reorientations observed in the ordered state. Magnetocrystalline anisotropy along the [110] direction stabilized by ∼50 meV per Mn by spin-orbit coupling (SOC) was found by DFT + U + SOC.

19.
J Phys Chem A ; 128(15): 3015-3023, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38593044

RESUMO

Respiratory viruses, such as influenza and severe acute respiratory syndrome coronavirus 2, represent a substantial public health burden and are largely transmitted through respiratory droplets and aerosols. Environmental factors such as relative humidity (RH) and temperature impact virus transmission rates, and a precise mechanistic understanding of the connection between these environmental factors and virus transmission would improve efforts to mitigate respiratory disease transmission. Previous studies on supermicrometer particles observed RH-dependent phase transitions and linked particle phase state to virus viability. Phase transitions in atmospheric aerosols are dependent on size in the submicrometer range, and actual respiratory particles are expelled over a large size range, including submicrometer aerosols that can transmit diseases over long distances. Here, we directly investigated the phase transitions of submicrometer model respiratory aerosols. A probe molecule, Nile red, was added to particle systems including multiple mucin/salt mixtures, a growth medium, and simulated lung fluid. For each system, the polarity-dependent fluorescence emission was measured following RH conditioning. Notably, the fluorescence measurements of mucin/NaCl and Dulbecco's modified Eagle's medium particles indicated that liquid-liquid phase separation (LLPS) also occurs in submicron particles, suggesting that LLPS can also impact the viability of viruses in submicron particles and thus affect aerosol virus transmission. Furthermore, the utility of fluorescence-based measurements to study submicrometer respiratory particle physicochemical properties in situ is demonstrated.


Assuntos
Mucinas , Aerossóis e Gotículas Respiratórios , Umidade , Aerossóis/química
20.
Nature ; 553(7686): 101-105, 2018 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-29258295

RESUMO

Genomic sequencing has driven precision-based oncology therapy; however, the genetic drivers of many malignancies remain unknown or non-targetable, so alternative approaches to the identification of therapeutic leads are necessary. Ependymomas are chemotherapy-resistant brain tumours, which, despite genomic sequencing, lack effective molecular targets. Intracranial ependymomas are segregated on the basis of anatomical location (supratentorial region or posterior fossa) and further divided into distinct molecular subgroups that reflect differences in the age of onset, gender predominance and response to therapy. The most common and aggressive subgroup, posterior fossa ependymoma group A (PF-EPN-A), occurs in young children and appears to lack recurrent somatic mutations. Conversely, posterior fossa ependymoma group B (PF-EPN-B) tumours display frequent large-scale copy number gains and losses but have favourable clinical outcomes. More than 70% of supratentorial ependymomas are defined by highly recurrent gene fusions in the NF-κB subunit gene RELA (ST-EPN-RELA), and a smaller number involve fusion of the gene encoding the transcriptional activator YAP1 (ST-EPN-YAP1). Subependymomas, a distinct histologic variant, can also be found within the supratetorial and posterior fossa compartments, and account for the majority of tumours in the molecular subgroups ST-EPN-SE and PF-EPN-SE. Here we describe mapping of active chromatin landscapes in 42 primary ependymomas in two non-overlapping primary ependymoma cohorts, with the goal of identifying essential super-enhancer-associated genes on which tumour cells depend. Enhancer regions revealed putative oncogenes, molecular targets and pathways; inhibition of these targets with small molecule inhibitors or short hairpin RNA diminished the proliferation of patient-derived neurospheres and increased survival in mouse models of ependymomas. Through profiling of transcriptional enhancers, our study provides a framework for target and drug discovery in other cancers that lack known genetic drivers and are therefore difficult to treat.


Assuntos
Elementos Facilitadores Genéticos/genética , Ependimoma/tratamento farmacológico , Ependimoma/genética , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes/genética , Terapia de Alvo Molecular , Oncogenes/genética , Fatores de Transcrição/metabolismo , Animais , Sequência de Bases , Ependimoma/classificação , Ependimoma/patologia , Feminino , Humanos , Camundongos , Medicina de Precisão , Interferência de RNA , Ensaios Antitumorais Modelo de Xenoenxerto
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