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1.
Cell ; 184(14): 3762-3773.e10, 2021 07 08.
Artículo en Inglés | MEDLINE | ID: mdl-34133943

RESUMEN

Sneezing is a vital respiratory reflex frequently associated with allergic rhinitis and viral respiratory infections. However, its neural circuit remains largely unknown. A sneeze-evoking region was discovered in both cat and human brainstems, corresponding anatomically to the central recipient zone of nasal sensory neurons. Therefore, we hypothesized that a neuronal population postsynaptic to nasal sensory neurons mediates sneezing in this region. By screening major presynaptic neurotransmitters/neuropeptides released by nasal sensory neurons, we found that neuromedin B (NMB) peptide is essential for signaling sneezing. Ablation of NMB-sensitive postsynaptic neurons in the sneeze-evoking region or deficiency in NMB receptor abolished the sneezing reflex. Remarkably, NMB-sensitive neurons further project to the caudal ventral respiratory group (cVRG). Chemical activation of NMB-sensitive neurons elicits action potentials in cVRG neurons and leads to sneezing behavior. Our study delineates a peptidergic pathway mediating sneezing, providing molecular insights into the sneezing reflex arc.


Asunto(s)
Tronco Encefálico/fisiopatología , Neuropéptidos/metabolismo , Nariz/fisiopatología , Reflejo/fisiología , Estornudo/fisiología , Animales , Modelos Animales de Enfermedad , Hipersensibilidad/fisiopatología , Masculino , Ratones Endogámicos C57BL , Neuroquinina B/análogos & derivados , Neuroquinina B/metabolismo , Neuronas/metabolismo , ARN Interferente Pequeño/metabolismo , Células Receptoras Sensoriales/fisiología , Canales Catiónicos TRPV/metabolismo , Grabación en Video
2.
Nat Immunol ; 23(1): 23-32, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34937933

RESUMEN

Systemic immune cell dynamics during coronavirus disease 2019 (COVID-19) are extensively documented, but these are less well studied in the (upper) respiratory tract, where severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) replicates1-6. Here, we characterized nasal and systemic immune cells in individuals with COVID-19 who were hospitalized or convalescent and compared the immune cells to those seen in healthy donors. We observed increased nasal granulocytes, monocytes, CD11c+ natural killer (NK) cells and CD4+ T effector cells during acute COVID-19. The mucosal proinflammatory populations positively associated with peripheral blood human leukocyte antigen (HLA)-DRlow monocytes, CD38+PD1+CD4+ T effector (Teff) cells and plasmablasts. However, there was no general lymphopenia in nasal mucosa, unlike in peripheral blood. Moreover, nasal neutrophils negatively associated with oxygen saturation levels in blood. Following convalescence, nasal immune cells mostly normalized, except for CD127+ granulocytes and CD38+CD8+ tissue-resident memory T cells (TRM). SARS-CoV-2-specific CD8+ T cells persisted at least 2 months after viral clearance in the nasal mucosa, indicating that COVID-19 has both transient and long-term effects on upper respiratory tract immune responses.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Nasofaringe/inmunología , Nariz/citología , Mucosa Respiratoria/inmunología , SARS-CoV-2/inmunología , Anticuerpos Antivirales/sangre , COVID-19/inmunología , COVID-19/patología , Granulocitos/inmunología , Antígenos HLA-DR/metabolismo , Humanos , Células Asesinas Naturales/inmunología , Células T de Memoria/inmunología , Monocitos/inmunología , Nasofaringe/citología , Nasofaringe/virología , Neutrófilos/inmunología , Nariz/inmunología , Nariz/virología , Estudios Prospectivos , Mucosa Respiratoria/citología , Mucosa Respiratoria/virología
3.
Nature ; 625(7996): 768-777, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38200313

RESUMEN

Cerebrospinal fluid (CSF) in the subarachnoid space around the brain has long been known to drain through the lymphatics to cervical lymph nodes1-17, but the connections and regulation have been challenging to identify. Here, using fluorescent CSF tracers in Prox1-GFP lymphatic reporter mice18, we found that the nasopharyngeal lymphatic plexus is a major hub for CSF outflow to deep cervical lymph nodes. This plexus had unusual valves and short lymphangions but no smooth-muscle coverage, whereas downstream deep cervical lymphatics had typical semilunar valves, long lymphangions and smooth muscle coverage that transported CSF to the deep cervical lymph nodes. α-Adrenergic and nitric oxide signalling in the smooth muscle cells regulated CSF drainage through the transport properties of deep cervical lymphatics. During ageing, the nasopharyngeal lymphatic plexus atrophied, but deep cervical lymphatics were not similarly altered, and CSF outflow could still be increased by adrenergic or nitric oxide signalling. Single-cell analysis of gene expression in lymphatic endothelial cells of the nasopharyngeal plexus of aged mice revealed increased type I interferon signalling and other inflammatory cytokines. The importance of evidence for the nasopharyngeal lymphatic plexus functioning as a CSF outflow hub is highlighted by its regression during ageing. Yet, the ageing-resistant pharmacological activation of deep cervical lymphatic transport towards lymph nodes can still increase CSF outflow, offering an approach for augmenting CSF clearance in age-related neurological conditions in which greater efflux would be beneficial.


Asunto(s)
Líquido Cefalorraquídeo , Vértebras Cervicales , Drenaje , Vasos Linfáticos , Animales , Ratones , Envejecimiento/metabolismo , Líquido Cefalorraquídeo/metabolismo , Vértebras Cervicales/metabolismo , Células Endoteliales/metabolismo , Fluorescencia , Genes Reporteros , Interferón Tipo I/inmunología , Interferón Tipo I/metabolismo , Vasos Linfáticos/fisiología , Miocitos del Músculo Liso/metabolismo , Óxido Nítrico/metabolismo , Nariz/fisiología , Faringe/metabolismo , Receptores Adrenérgicos alfa/metabolismo , Análisis de la Célula Individual , Transducción de Señal
4.
Nature ; 596(7872): 423-427, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34161961

RESUMEN

The emergence of SARS-CoV-2 variants that partially evade neutralizing antibodies poses a threat to the efficacy of current COVID-19 vaccines1,2. The Ad26.COV2.S vaccine expresses a stabilized spike protein from the WA1/2020 strain of SARS-CoV-2, and has recently demonstrated protective efficacy against symptomatic COVID-19 in humans in several geographical regions-including in South Africa, where 95% of sequenced viruses in cases of COVID-19 were the B.1.351 variant3. Here we show that Ad26.COV2.S elicits humoral and cellular immune responses that cross-react with the B.1.351 variant and protects against B.1.351 challenge in rhesus macaques. Ad26.COV2.S induced lower binding and neutralizing antibodies against B.1.351 as compared to WA1/2020, but elicited comparable CD8 and CD4 T cell responses against the WA1/2020, B.1.351, B.1.1.7, P.1 and CAL.20C variants. B.1.351 infection of control rhesus macaques resulted in higher levels of virus replication in bronchoalveolar lavage and nasal swabs than did WA1/2020 infection. Ad26.COV2.S provided robust protection against both WA1/2020 and B.1.351, although we observed higher levels of virus in vaccinated macaques after B.1.351 challenge. These data demonstrate that Ad26.COV2.S provided robust protection against B.1.351 challenge in rhesus macaques. Our findings have important implications for vaccine control of SARS-CoV-2 variants of concern.


Asunto(s)
Vacunas contra la COVID-19/inmunología , COVID-19/prevención & control , COVID-19/virología , Inmunidad Celular , Inmunidad Humoral , Macaca mulatta/inmunología , SARS-CoV-2/inmunología , Ad26COVS1 , Animales , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Líquido del Lavado Bronquioalveolar/virología , COVID-19/inmunología , COVID-19/patología , Femenino , Macaca mulatta/virología , Masculino , Nariz/virología , SARS-CoV-2/crecimiento & desarrollo , SARS-CoV-2/patogenicidad , Linfocitos T/inmunología , Replicación Viral
5.
PLoS Genet ; 20(2): e1011159, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38377146

RESUMEN

Common genetic variants in the repressive GATA-family transcription factor (TF) TRPS1 locus are associated with breast cancer risk, and luminal breast cancer cell lines are particularly sensitive to TRPS1 knockout. We introduced an inducible degron tag into the native TRPS1 locus within a luminal breast cancer cell line to identify the direct targets of TRPS1 and determine how TRPS1 mechanistically regulates gene expression. We acutely deplete over 80 percent of TRPS1 from chromatin within 30 minutes of inducing degradation. We find that TRPS1 regulates transcription of hundreds of genes, including those related to estrogen signaling. TRPS1 directly regulates chromatin structure, which causes estrogen receptor alpha (ER) to redistribute in the genome. ER redistribution leads to both repression and activation of dozens of ER target genes. Downstream from these primary effects, TRPS1 depletion represses cell cycle-related gene sets and reduces cell doubling rate. Finally, we show that high TRPS1 activity, calculated using a gene expression signature defined by primary TRPS1-regulated genes, is associated with worse breast cancer patient prognosis. Taken together, these data suggest a model in which TRPS1 modulates the genomic distribution of ER, both activating and repressing transcription of genes related to cancer cell fitness.


Asunto(s)
Neoplasias de la Mama , Cromatina , Dedos , Enfermedades del Cabello , Síndrome de Langer-Giedion , Nariz , Femenino , Humanos , Neoplasias de la Mama/genética , Cromatina/genética , Receptor alfa de Estrógeno/genética , Dedos/anomalías , Factores de Transcripción GATA , Expresión Génica , Genes cdc , Nariz/anomalías , Proteínas Represoras/genética
6.
PLoS Pathog ; 20(2): e1012026, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38377132

RESUMEN

Influenza A virus (FLUAV) infects a wide range of hosts and human-to-swine spillover events are frequently reported. However, only a few of these human viruses have become established in pigs and the host barriers and molecular mechanisms driving adaptation to the swine host remain poorly understood. We previously found that infection of pigs with a 2:6 reassortant virus (hVIC/11) containing the hemagglutinin (HA) and neuraminidase (NA) gene segments from the human strain A/Victoria/361/2011 (H3N2) and internal gene segments of an endemic swine strain (sOH/04) resulted in a fixed amino acid substitution in the HA (A138S, mature H3 HA numbering). In silico analysis revealed that S138 became predominant among swine H3N2 virus sequences deposited in public databases, while 138A predominates in human isolates. To understand the role of the HA A138S substitution in the adaptation of a human-origin FLUAV HA to swine, we infected pigs with the hVIC/11A138S mutant and analyzed pathogenesis and transmission compared to hVIC/11 and sOH/04. Our results showed that the hVIC/11A138S virus had an intermediary pathogenesis between hVIC/11 and sOH/04. The hVIC/11A138S infected the upper respiratory tract, right caudal, and both cranial lobes while hVIC/11 was only detected in nose and trachea samples. Viruses induced a distinct expression pattern of various pro-inflammatory cytokines such as IL-8, TNF-α, and IFN-ß. Flow cytometric analysis of lung samples revealed a significant reduction of porcine alveolar macrophages (PAMs) in hVIC/11A138S-infected pigs compared to hVIC/11 while a MHCIIlowCD163neg population was increased. The hVIC/11A138S showed a higher affinity for PAMs than hVIC/11, noted as an increase of infected PAMs in bronchoalveolar lavage fluid (BALF), and showed no differences in the percentage of HA-positive PAMs compared to sOH/04. This increased infection of PAMs led to an increase of granulocyte-monocyte colony-stimulating factor (GM-CSF) stimulation but a reduced expression of peroxisome proliferator-activated receptor gamma (PPARγ) in the sOH/04-infected group. Analysis using the PAM cell line 3D4/21 revealed that the A138S substitution improved replication and apoptosis induction in this cell type compared to hVIC/11 but at lower levels than sOH/04. Overall, our study indicates that adaptation of human viruses to the swine host involves an increased affinity for the lower respiratory tract and alveolar macrophages.


Asunto(s)
Subtipo H3N2 del Virus de la Influenza A , Virus de la Influenza A , Humanos , Animales , Porcinos , Subtipo H3N2 del Virus de la Influenza A/genética , Macrófagos Alveolares , Aminoácidos , Hemaglutininas , Nariz
7.
Nature ; 586(7830): 567-571, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32756549

RESUMEN

A vaccine for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is needed to control the coronavirus disease 2019 (COVID-19) global pandemic. Structural studies have led to the development of mutations that stabilize Betacoronavirus spike proteins in the prefusion state, improving their expression and increasing immunogenicity1. This principle has been applied to design mRNA-1273, an mRNA vaccine that encodes a SARS-CoV-2 spike protein that is stabilized in the prefusion conformation. Here we show that mRNA-1273 induces potent neutralizing antibody responses to both wild-type (D614) and D614G mutant2 SARS-CoV-2 as well as CD8+ T cell responses, and protects against SARS-CoV-2 infection in the lungs and noses of mice without evidence of immunopathology. mRNA-1273 is currently in a phase III trial to evaluate its efficacy.


Asunto(s)
Betacoronavirus/inmunología , Infecciones por Coronavirus/inmunología , Infecciones por Coronavirus/prevención & control , Pandemias/prevención & control , Neumonía Viral/inmunología , Neumonía Viral/prevención & control , Vacunas Virales/inmunología , Vacuna nCoV-2019 mRNA-1273 , Animales , Anticuerpos Neutralizantes/inmunología , Betacoronavirus/genética , Linfocitos T CD8-positivos/inmunología , COVID-19 , Vacunas contra la COVID-19 , Ensayos Clínicos Fase III como Asunto , Infecciones por Coronavirus/genética , Infecciones por Coronavirus/virología , Femenino , Pulmón/inmunología , Pulmón/virología , Ratones , Mutación , Nariz/inmunología , Nariz/virología , Neumonía Viral/virología , ARN Mensajero/genética , ARN Viral/genética , SARS-CoV-2 , Células TH1/inmunología , Receptor Toll-Like 4/agonistas , Receptor Toll-Like 4/inmunología , Vacunas Virales/química , Vacunas Virales/genética
8.
Proc Natl Acad Sci U S A ; 120(31): e2303928120, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37494398

RESUMEN

Although sensor technologies have allowed us to outperform the human senses of sight, hearing, and touch, the development of artificial noses is significantly behind their biological counterparts. This largely stems from the sophistication of natural olfaction, which relies on both fluid dynamics within the nasal anatomy and the response patterns of hundreds to thousands of unique molecular-scale receptors. We designed a sensing approach to identify volatiles inspired by the fluid dynamics of the nose, allowing us to extract information from a single sensor (here, the reflectance spectra from a mesoporous one-dimensional photonic crystal) rather than relying on a large sensor array. By accentuating differences in the nonequilibrium mass-transport dynamics of vapors and training a machine learning algorithm on the sensor output, we clearly identified polar and nonpolar volatile compounds, determined the mixing ratios of binary mixtures, and accurately predicted the boiling point, flash point, vapor pressure, and viscosity of a number of volatile liquids, including several that had not been used for training the model. We further implemented a bioinspired active sniffing approach, in which the analyte delivery was performed in well-controlled 'inhale-exhale' sequences, enabling an additional modality of differentiation and reducing the duration of data collection and analysis to seconds. Our results outline a strategy to build accurate and rapid artificial noses for volatile compounds that can provide useful information such as the composition and physical properties of chemicals, and can be applied in a variety of fields, including disease diagnosis, hazardous waste management, and healthy building monitoring.


Asunto(s)
Nariz , Olfato , Humanos , Nariz Electrónica , Aprendizaje Automático , Gases
9.
Proc Natl Acad Sci U S A ; 120(13): e2213584120, 2023 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-36943879

RESUMEN

Virtually all living cells are encased in glycans. They perform key cellular functions such as immunomodulation and cell-cell recognition. Yet, how their composition and configuration affect their functions remains enigmatic. Here, we constructed isogenic capsule-switch mutants harboring 84 types of capsular polysaccharides (CPSs) in Streptococcus pneumoniae. This collection enables us to systematically measure the affinity of structurally related CPSs to primary human nasal and bronchial epithelial cells. Contrary to the paradigm, the surface charge does not appreciably affect epithelial cell binding. Factors that affect adhesion to respiratory cells include the number of rhamnose residues and the presence of human-like glycomotifs in CPS. Besides, pneumococcal colonization stimulated the production of interleukin 6 (IL-6), granulocyte-macrophage colony-stimulating factor (GM-CSF), and monocyte chemoattractantprotein-1 (MCP-1) in nasal epithelial cells, which also appears to be dependent on the serotype. Together, our results reveal glycomotifs of surface polysaccharides that are likely to be important for colonization and survival in the human airway.


Asunto(s)
Células Epiteliales , Streptococcus pneumoniae , Humanos , Streptococcus pneumoniae/genética , Streptococcus pneumoniae/metabolismo , Sistema Respiratorio , Polisacáridos/metabolismo , Nariz
10.
Proc Natl Acad Sci U S A ; 120(17): e2300376120, 2023 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-37068258

RESUMEN

The high transmissibility of SARS-CoV-2 Omicron subvariants was generally ascribed to immune escape. It remained unclear whether the emerging variants have gradually acquired replicative fitness in human respiratory epithelial cells. We sought to evaluate the replicative fitness of BA.5 and earlier variants in physiologically active respiratory organoids. BA.5 exhibited a dramatically increased replicative capacity and infectivity than B.1.1.529 and an ancestral strain wildtype (WT) in human nasal and airway organoids. BA.5 spike pseudovirus showed a significantly higher entry efficiency than that carrying WT or B.1.1.529 spike. Notably, we observed prominent syncytium formation in BA.5-infected nasal and airway organoids, albeit elusive in WT- and B.1.1.529-infected organoids. BA.5 spike-triggered syncytium formation was verified by lentiviral overexpression of spike in nasal organoids. Moreover, BA.5 replicated modestly in alveolar organoids, with a significantly lower titer than B.1.1.529 and WT. Collectively, the higher entry efficiency and fusogenic activity of BA.5 spike potentiated viral spread through syncytium formation in the human airway epithelium, leading to enhanced replicative fitness and immune evasion, whereas the attenuated replicative capacity of BA.5 in the alveolar organoids may account for its benign clinical manifestation.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/genética , Nariz , Organoides , Glicoproteína de la Espiga del Coronavirus/genética , Anticuerpos Neutralizantes , Anticuerpos Antivirales
11.
J Virol ; 98(1): e0161823, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38174928

RESUMEN

The global evolution of SARS-CoV-2 depends in part upon the evolutionary dynamics within individual hosts with varying immune histories. To characterize the within-host evolution of acute SARS-CoV-2 infection, we sequenced saliva and nasal samples collected daily from vaccinated and unvaccinated individuals early during infection. We show that longitudinal sampling facilitates high-confidence genetic variant detection and reveals evolutionary dynamics missed by less-frequent sampling strategies. Within-host dynamics in both unvaccinated and vaccinated individuals appeared largely stochastic; however, in rare cases, minor genetic variants emerged to frequencies sufficient for forward transmission. Finally, we detected significant genetic compartmentalization of viral variants between saliva and nasal swab sample sites in many individuals. Altogether, these data provide a high-resolution profile of within-host SARS-CoV-2 evolutionary dynamics.IMPORTANCEWe detail the within-host evolutionary dynamics of SARS-CoV-2 during acute infection in 31 individuals using daily longitudinal sampling. We characterized patterns of mutational accumulation for unvaccinated and vaccinated individuals, and observed that temporal variant dynamics in both groups were largely stochastic. Comparison of paired nasal and saliva samples also revealed significant genetic compartmentalization between tissue environments in multiple individuals. Our results demonstrate how selection, genetic drift, and spatial compartmentalization all play important roles in shaping the within-host evolution of SARS-CoV-2 populations during acute infection.


Asunto(s)
Evolución Molecular , Flujo Genético , SARS-CoV-2 , Humanos , COVID-19/virología , Nariz/virología , Saliva/virología , SARS-CoV-2/genética , Masculino , Femenino , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad
12.
PLoS Pathog ; 19(9): e1011630, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37669280

RESUMEN

Streptococcus pneumoniae is a leading cause of community-acquired pneumonia and bacteraemia and is capable of remarkable phenotypic plasticity, responding rapidly to environmental change. Pneumococcus is a nasopharyngeal commensal, but is responsible for severe, acute infections following dissemination within-host. Pneumococcus is adept at utilising host resources, but the airways are compartmentalised and those resources are not evenly distributed. Challenges and opportunities in metabolite acquisition within different airway niches may contribute to the commensal-pathogen switch when pneumococcus moves from nasopharynx into lungs. We used NMR to characterise the metabolic landscape of the mouse airways, in health and during infection. Using paired nasopharynx and lung samples from naïve animals, we identified fundamental differences in metabolite bioavailability between airway niches. Pneumococcal pneumonia was associated with rapid and dramatic shifts in the lung metabolic environment, whilst nasopharyngeal carriage led to only modest change in upper airway metabolite profiles. NMR spectra derived from the nasopharynx of mice infected with closely-related pneumococcal strains that differ in their colonisation potential could be distinguished from one another using multivariate dimensionality reduction methods. The resulting models highlighted that increased branched-chain amino acid (BCAA) bioavailability in nasopharynx is a feature of infection with the high colonisation potential strain. Subsequent analysis revealed increased expression of BCAA transport genes and increased intracellular concentrations of BCAA in that same strain. Movement from upper to lower airway environments is associated with shifting challenges in metabolic resource allocation for pneumococci. Efficient biosynthesis, liberation or acquisition of BCAA is a feature of adaptation to nasopharyngeal colonisation.


Asunto(s)
Nariz , Infecciones Neumocócicas , Animales , Ratones , Metabolómica , Streptococcus pneumoniae , Aminoácidos de Cadena Ramificada
13.
PLoS Pathog ; 19(8): e1011509, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37540710

RESUMEN

Among the many oral streptococci, Streptococcus pneumoniae (Spn) stands out for the capacity of encapsulated strains to cause invasive infection. Spread beyond upper airways, however, is a biological dead end for the organism, raising the question of the benefits of expending energy to coat its surface in a thick layer of capsular polysaccharide (CPS). In this study, we compare mutants of two serotypes expressing different amounts of CPS and test these in murine models of colonization, invasion infection and transmission. Our analysis of the effect of CPS amount shows that Spn expresses a capsule of sufficient thickness to shield its surface from the deposition of complement and binding of antibody to underlying epitopes. While effective shielding is permissive for invasive infection, its primary contribution to the organism appears to be in the dynamics of colonization. A thicker capsule increases bacterial retention in the nasopharynx, the first event in colonization, and also impedes IL-17-dependent clearance during late colonization. Enhanced colonization is associated with increased opportunity for host-to-host transmission. Additionally, we document substantial differences in CPS amount among clinical isolates of three common serotypes. Together, our findings show that CPS amount is highly variable among Spn and could be an independent determinant affecting host interactions.


Asunto(s)
Infecciones Neumocócicas , Streptococcus pneumoniae , Animales , Ratones , Streptococcus pneumoniae/metabolismo , Streptococcus , Polisacáridos/metabolismo , Nasofaringe/microbiología , Nariz , Infecciones Neumocócicas/microbiología , Cápsulas Bacterianas/genética
14.
Proc Natl Acad Sci U S A ; 119(31): e2122563119, 2022 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-35858384

RESUMEN

The elephant's trunk is multifunctional: It must be flexible to wrap around vegetation, but tough to knock down trees and resist attack. How can one appendage satisfy both constraints? In this combined experimental and theoretical study, we challenged African elephants to reach far-away objects with only horizontal extensions of their trunk. Surprisingly, the trunk does not extend uniformly, but instead exhibits a dorsal "joint" that stretches 15% more than the corresponding ventral section. Using material testing with the skin of a deceased elephant, we show that the asymmetry is due in part to patterns of the skin. The dorsal skin is folded and 15% more pliable than the wrinkled ventral skin. Skin folds protect the dorsal section and stretch to facilitate downward wrapping, the most common gripping style when picking up items. The elephant's skin is also sufficiently stiff to influence its mechanics: At the joint, the skin requires 13 times more energy to stretch than the corresponding length of muscle. The use of wrinkles and folds to modulate stiffness may provide a valuable concept for both biology and soft robotics.


Asunto(s)
Elefantes , Nariz , Fenómenos Fisiológicos de la Piel , Piel , Animales , Elefantes/anatomía & histología , Elefantes/fisiología , Nariz/anatomía & histología , Nariz/fisiología
15.
J Allergy Clin Immunol ; 153(1): 122-131, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37742934

RESUMEN

BACKGROUND: Little is known about nasal epithelial gene expression and total IgE in youth. OBJECTIVE: We aimed to identify genes whose nasal epithelial expression differs by total IgE in youth, and group them into modules that could be mapped to airway epithelial cell types. METHODS: We conducted a transcriptome-wide association study of total IgE in 469 Puerto Ricans aged 9 to 20 years who participated in the Epigenetic Variation and Childhood Asthma in Puerto Ricans study, separately in all subjects and in those with asthma. We then attempted to replicate top findings for each analysis using data from 3 cohorts. Genes with a Benjamini-Hochberg-adjusted P value of less than .05 in the Epigenetic Variation and Childhood Asthma in Puerto Ricans study and a P value of less than .05 in the same direction of association in 1 or more replication cohort were considered differentially expressed genes (DEGs). DEGs for total IgE in subjects with asthma were further dissected into gene modules using coexpression analysis, and such modules were mapped to specific cell types in airway epithelia using public single-cell RNA-sequencing data. RESULTS: A higher number of DEGs for total IgE were identified in subjects with asthma (n = 1179 DEGs) than in all subjects (n = 631 DEGs). In subjects with asthma, DEGs were mapped to 11 gene modules. The top module for positive correlation with total IgE was mapped to myoepithelial and mucus secretory cells in lower airway epithelia and was regulated by IL-4, IL5, IL-13, and IL-33. Within this module, hub genes included CDH26, FETUB, NTRK2, CCBL1, CST1, and CST2. Furthermore, an enrichment analysis showed overrepresentation of genes in signaling pathways for synaptogenesis, IL-13, and ferroptosis, supporting interactions between interleukin- and acetylcholine-induced responses. CONCLUSIONS: Our findings for nasal epithelial gene expression support neuroimmune coregulation of total IgE in youth with asthma.


Asunto(s)
Asma , Interleucina-13 , Niño , Humanos , Adolescente , Interleucina-13/genética , Nariz , Transcriptoma , Inmunoglobulina E
16.
J Allergy Clin Immunol ; 153(6): 1563-1573, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38423369

RESUMEN

BACKGROUND: Five distinct respiratory phenotypes based on latent classes of longitudinal patterns of wheezing, allergic sensitization. and pulmonary function measured in urban children from ages from 0 to 7 years have previously been described. OBJECTIVE: Our aim was to determine whether distinct respiratory phenotypes are associated with early-life upper respiratory microbiota development and environmental microbial exposures. METHODS: Microbiota profiling was performed using 16S ribosomal RNA-based sequencing of nasal samples collected at age 12 months (n = 120) or age 36 months (n = 142) and paired house dust samples collected at 3 months (12-month, n = 73; 36-month, n = 90) from all 4 centers in the Urban Environment and Childhood Asthma (URECA) cohort. RESULTS: In these high-risk urban children, nasal microbiota increased in diversity between ages 12 and 36 months (ß = 2.04; P = .006). Age-related changes in microbiota evenness differed significantly by respiratory phenotypes (interaction P = .0007), increasing most in the transient wheeze group. At age 12 months, respiratory illness (R2 = 0.055; P = .0001) and dominant bacterial genus (R2 = 0.59; P = .0001) explained variance in nasal microbiota composition, and enrichment of Moraxella and Haemophilus members was associated with both transient and high-wheeze respiratory phenotypes. By age 36 months, nasal microbiota was significantly associated with respiratory phenotypes (R2 = 0.019; P = .0376), and Moraxella-dominated microbiota was associated specifically with atopy-associated phenotypes. Analysis of paired house dust and nasal samples indicated that 12 month olds with low wheeze and atopy incidence exhibited the largest number of shared bacterial taxa with their environment. CONCLUSION: Nasal microbiota development over the course of early childhood and composition at age 3 years are associated with longitudinal respiratory phenotypes. These data provide evidence supporting an early-life window of airway microbiota development that is influenced by environmental microbial exposures in infancy and associates with wheeze- and atopy-associated respiratory phenotypes through age 7 years.


Asunto(s)
Microbiota , Fenotipo , Ruidos Respiratorios , Población Urbana , Humanos , Lactante , Preescolar , Masculino , Femenino , Estudios Longitudinales , Asma/microbiología , Asma/epidemiología , Polvo/análisis , Polvo/inmunología , Exposición a Riesgos Ambientales , Nariz/microbiología , ARN Ribosómico 16S/genética , Niño
17.
Emerg Infect Dis ; 30(4): 766-769, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38526207

RESUMEN

We describe a classic case of nasal rhinosporidiosis in a woman who resided in Johannesburg, South Africa, but originated from a rural area in Eastern Cape Province. We confirmed histologic diagnosis using PCR testing and compared details with those from records on 17 other cases from South Africa.


Asunto(s)
Rinosporidiosis , Femenino , Humanos , Sudáfrica/epidemiología , Rinosporidiosis/diagnóstico , Nariz
18.
Emerg Infect Dis ; 30(4): 783-785, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38526242

RESUMEN

We describe 10 patients with nonkeratitis Acanthamoeba infection who reported performing nasal rinsing before becoming ill. All were immunocompromised, 7 had chronic sinusitis, and many used tap water for nasal rinsing. Immunocompromised persons should be educated about safe nasal rinsing to prevent free-living ameba infections.


Asunto(s)
Amebiasis , Nariz , Humanos , Estados Unidos/epidemiología , Amebiasis/epidemiología , Huésped Inmunocomprometido
19.
Am J Hum Genet ; 108(1): 134-147, 2021 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-33340455

RESUMEN

The ubiquitin-proteasome system facilitates the degradation of unstable or damaged proteins. UBR1-7, which are members of hundreds of E3 ubiquitin ligases, recognize and regulate the half-life of specific proteins on the basis of their N-terminal sequences ("N-end rule"). In seven individuals with intellectual disability, epilepsy, ptosis, hypothyroidism, and genital anomalies, we uncovered bi-allelic variants in UBR7. Their phenotype differs significantly from that of Johanson-Blizzard syndrome (JBS), which is caused by bi-allelic variants in UBR1, notably by the presence of epilepsy and the absence of exocrine pancreatic insufficiency and hypoplasia of nasal alae. While the mechanistic etiology of JBS remains uncertain, mutation of both Ubr1 and Ubr2 in the mouse or of the C. elegans UBR5 ortholog results in Notch signaling defects. Consistent with a potential role in Notch signaling, C. elegans ubr-7 expression partially overlaps with that of ubr-5, including in neurons, as well as the distal tip cell that plays a crucial role in signaling to germline stem cells via the Notch signaling pathway. Analysis of ubr-5 and ubr-7 single mutants and double mutants revealed genetic interactions with the Notch receptor gene glp-1 that influenced development and embryo formation. Collectively, our findings further implicate the UBR protein family and the Notch signaling pathway in a neurodevelopmental syndrome with epilepsy, ptosis, and hypothyroidism that differs from JBS. Further studies exploring a potential role in histone regulation are warranted given clinical overlap with KAT6B disorders and the interaction of UBR7 and UBR5 with histones.


Asunto(s)
Epilepsia/genética , Hipotiroidismo/genética , Trastornos del Neurodesarrollo/genética , Receptores Notch/genética , Transducción de Señal/genética , Ubiquitina-Proteína Ligasas/genética , Animales , Ano Imperforado/genética , Caenorhabditis elegans/genética , Línea Celular , Displasia Ectodérmica/genética , Trastornos del Crecimiento/genética , Células HEK293 , Pérdida Auditiva Sensorineural/genética , Histonas/genética , Humanos , Discapacidad Intelectual/genética , Ratones , Mutación/genética , Nariz/anomalías , Enfermedades Pancreáticas/genética , Complejo de la Endopetidasa Proteasomal/genética
20.
J Clin Microbiol ; 62(1): e0115223, 2024 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-38126761

RESUMEN

The objective of this study was to assess the clinical performances of PhenoMATRIX and PhenoMATRIX PLUS for the screening of methicillin-resistant Staphylococcus aureus (MRSA) from nasal and inguinal/perineal ESwabs using chromogenic media. The automated performances were compared to the manual reading. Additionally, we evaluated PhenoMATRIX PLUS for the automatic release of the negative results to the Laboratory Information System (LIS) and the automatic discharge of the negative plates from the incubators. A total of 6,771 non-duplicate specimens were used by PhenoMATRIX as a machine learning model. The validation of these settings was performed on 17,223 non-duplicate specimens. The MRSA positivity rate was 5% (866/17,223). Validated settings were then used by PhenoMATRIX PLUS on another 1,409 non-duplicate specimens. The sensitivities of PhenoMATRIX and PhenoMATRIX PLUS were 99.8% [95% confidence interval (CI), 99.2%-99.9%] and 100% (95% CI, 92.1%-100%), respectively. The specificities of PhenoMATRIX and PhenoMATRIX PLUS were 99.1% (95% CI, 99.0%-99.2%) and 95.2% (95% CI, 93.8%-96.1%), respectively. All the 1,297 MRSA-negative specimens analyzed by PhenoMATRIX PLUS were automatically released and sent to the LIS immediately after availability of the culture image on the WASPLab (100% accuracy). All negative media plates were automatically discarded. PhenoMATRIX PLUS decreases the time spent by technologists on negative plates and ensures optimal usage of the incubators' capacity.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Humanos , Técnicas Bacteriológicas/métodos , Sensibilidad y Especificidad , Compuestos Cromogénicos , Nariz , Infecciones Estafilocócicas/diagnóstico , Medios de Cultivo
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