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1.
Mol Cell ; 84(6): 1101-1119.e9, 2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38428433

RESUMEN

Mitochondrial outer membrane ⍺-helical proteins play critical roles in mitochondrial-cytoplasmic communication, but the rules governing the targeting and insertion of these biophysically diverse proteins remain unknown. Here, we first defined the complement of required mammalian biogenesis machinery through genome-wide CRISPRi screens using topologically distinct membrane proteins. Systematic analysis of nine identified factors across 21 diverse ⍺-helical substrates reveals that these components are organized into distinct targeting pathways that act on substrates based on their topology. NAC is required for the efficient targeting of polytopic proteins, whereas signal-anchored proteins require TTC1, a cytosolic chaperone that physically engages substrates. Biochemical and mutational studies reveal that TTC1 employs a conserved TPR domain and a hydrophobic groove in its C-terminal domain to support substrate solubilization and insertion into mitochondria. Thus, the targeting of diverse mitochondrial membrane proteins is achieved through topological triaging in the cytosol using principles with similarities to ER membrane protein biogenesis systems.


Asunto(s)
Membranas Mitocondriales , Proteínas de Saccharomyces cerevisiae , Animales , Membranas Mitocondriales/metabolismo , Mitocondrias/genética , Mitocondrias/metabolismo , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Mutación , Proteínas Mitocondriales/genética , Proteínas Mitocondriales/metabolismo , Transporte de Proteínas , Proteínas de Saccharomyces cerevisiae/metabolismo , Mamíferos/metabolismo
2.
Nature ; 613(7943): 340-344, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36384167

RESUMEN

During recent decades, pathogens that originated in bats have become an increasing public health concern. A major challenge is to identify how those pathogens spill over into human populations to generate a pandemic threat1. Many correlational studies associate spillover with changes in land use or other anthropogenic stressors2,3, although the mechanisms underlying the observed correlations have not been identified4. One limitation is the lack of spatially and temporally explicit data on multiple spillovers, and on the connections among spillovers, reservoir host ecology and behaviour and viral dynamics. We present 25 years of data on land-use change, bat behaviour and spillover of Hendra virus from Pteropodid bats to horses in subtropical Australia. These data show that bats are responding to environmental change by persistently adopting behaviours that were previously transient responses to nutritional stress. Interactions between land-use change and climate now lead to persistent bat residency in agricultural areas, where periodic food shortages drive clusters of spillovers. Pulses of winter flowering of trees in remnant forests appeared to prevent spillover. We developed integrative Bayesian network models based on these phenomena that accurately predicted the presence or absence of clusters of spillovers in each of the 25 years. Our long-term study identifies the mechanistic connections between habitat loss, climate and increased spillover risk. It provides a framework for examining causes of bat virus spillover and for developing ecological countermeasures to prevent pandemics.


Asunto(s)
Quirópteros , Ecología , Ecosistema , Virus Hendra , Caballos , Animales , Humanos , Australia , Teorema de Bayes , Quirópteros/virología , Clima , Caballos/virología , Salud Pública , Virus Hendra/aislamiento & purificación , Recursos Naturales , Agricultura , Bosques , Abastecimiento de Alimentos , Pandemias/prevención & control , Pandemias/veterinaria
3.
Nature ; 623(7988): 842-852, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37853127

RESUMEN

Optimum protein function and biochemical activity critically depends on water availability because solvent thermodynamics drive protein folding and macromolecular interactions1. Reciprocally, macromolecules restrict the movement of 'structured' water molecules within their hydration layers, reducing the available 'free' bulk solvent and therefore the total thermodynamic potential energy of water, or water potential. Here, within concentrated macromolecular solutions such as the cytosol, we found that modest changes in temperature greatly affect the water potential, and are counteracted by opposing changes in osmotic strength. This duality of temperature and osmotic strength enables simple manipulations of solvent thermodynamics to prevent cell death after extreme cold or heat shock. Physiologically, cells must sustain their activity against fluctuating temperature, pressure and osmotic strength, which impact water availability within seconds. Yet, established mechanisms of water homeostasis act over much slower timescales2,3; we therefore postulated the existence of a rapid compensatory response. We find that this function is performed by water potential-driven changes in macromolecular assembly, particularly biomolecular condensation of intrinsically disordered proteins. The formation and dissolution of biomolecular condensates liberates and captures free water, respectively, quickly counteracting thermal or osmotic perturbations of water potential, which is consequently robustly buffered in the cytoplasm. Our results indicate that biomolecular condensation constitutes an intrinsic biophysical feedback response that rapidly compensates for intracellular osmotic and thermal fluctuations. We suggest that preserving water availability within the concentrated cytosol is an overlooked evolutionary driver of protein (dis)order and function.


Asunto(s)
Sustancias Macromoleculares , Proteínas , Solventes , Termodinámica , Agua , Muerte Celular , Citosol/química , Citosol/metabolismo , Homeostasis , Sustancias Macromoleculares/química , Sustancias Macromoleculares/metabolismo , Concentración Osmolar , Presión , Proteínas/química , Proteínas/metabolismo , Solventes/química , Solventes/metabolismo , Temperatura , Factores de Tiempo , Agua/química , Agua/metabolismo
4.
PLoS Genet ; 20(5): e1011230, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38713708

RESUMEN

Fuchs endothelial corneal dystrophy (FECD) is an age-related cause of vision loss, and the most common repeat expansion-mediated disease in humans characterised to date. Up to 80% of European FECD cases have been attributed to expansion of a non-coding CTG repeat element (termed CTG18.1) located within the ubiquitously expressed transcription factor encoding gene, TCF4. The non-coding nature of the repeat and the transcriptomic complexity of TCF4 have made it extremely challenging to experimentally decipher the molecular mechanisms underlying this disease. Here we comprehensively describe CTG18.1 expansion-driven molecular components of disease within primary patient-derived corneal endothelial cells (CECs), generated from a large cohort of individuals with CTG18.1-expanded (Exp+) and CTG 18.1-independent (Exp-) FECD. We employ long-read, short-read, and spatial transcriptomic techniques to interrogate expansion-specific transcriptomic biomarkers. Interrogation of long-read sequencing and alternative splicing analysis of short-read transcriptomic data together reveals the global extent of altered splicing occurring within Exp+ FECD, and unique transcripts associated with CTG18.1-expansions. Similarly, differential gene expression analysis highlights the total transcriptomic consequences of Exp+ FECD within CECs. Furthermore, differential exon usage, pathway enrichment and spatial transcriptomics reveal TCF4 isoform ratio skewing solely in Exp+ FECD with potential downstream functional consequences. Lastly, exome data from 134 Exp- FECD cases identified rare (minor allele frequency <0.005) and potentially deleterious (CADD>15) TCF4 variants in 7/134 FECD Exp- cases, suggesting that TCF4 variants independent of CTG18.1 may increase FECD risk. In summary, our study supports the hypothesis that at least two distinct pathogenic mechanisms, RNA toxicity and TCF4 isoform-specific dysregulation, both underpin the pathophysiology of FECD. We anticipate these data will inform and guide the development of translational interventions for this common triplet-repeat mediated disease.


Asunto(s)
Distrofia Endotelial de Fuchs , Factor de Transcripción 4 , Expansión de Repetición de Trinucleótido , Humanos , Factor de Transcripción 4/genética , Factor de Transcripción 4/metabolismo , Expansión de Repetición de Trinucleótido/genética , Distrofia Endotelial de Fuchs/genética , Empalme Alternativo/genética , Transcriptoma/genética , Células Endoteliales/metabolismo , Endotelio Corneal/metabolismo , Endotelio Corneal/patología , Masculino
5.
Blood ; 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38306597

RESUMEN

Treatment of the common nodal peripheral T-cell lymphomas (PTCLs), which include PTCL, not otherwise specified (PTCL, NOS), anaplastic large cell lymphomas, and T-follicular helper lymphomas, is evolving. These entities are currently treated similarly with CHOP or CHOEP for CD30-negative diseases or brentuximab vedotin plus CHP for CD30-positive diseases, followed by consolidation with autologous stem cell transplant in first remission. Ongoing improvements in PTCL classification, identification of predictive biomarkers, and development of new targeted agents will lead to more specific therapies that address the unique biologic and clinical properties of each entity. For example, widespread efforts focused on molecular profiling of PTCL, NOS is likely to identify distinct subtypes that warrant different treatment approaches. New agents, such as EZH1/2 and JAK/STAT pathway inhibitors, are broadening treatment options for relapsed or refractory disease. Furthermore, promising strategies optimizing immune therapy for PTCL are currently under investigation and have potential to significantly alter the therapeutic landscape. Ongoing front-line study designs incorporate understanding of disease biology and drug sensitivities and are poised to evaluate whether newer targeted agents should be incorporated into the front-line settings for the various disease entities. Although current treatment strategies lump most disease entities together, future treatment will include distinct strategies for each disease subtype that optimizes therapy for individuals. This movement towards individualized therapy will ultimately lead to dramatic improvements in prognosis for patients with PTCL.

6.
Circulation ; 149(3): 217-226, 2024 01 16.
Artículo en Inglés | MEDLINE | ID: mdl-38014550

RESUMEN

BACKGROUND: Although low-density lipoprotein cholesterol (LDL-C) remains the primary cholesterol target in clinical practice in children and adults, non-high-density lipoprotein cholesterol (non-HDL-C) has been suggested as a more accurate measure of atherosclerotic cardiovascular disease (ASCVD) risk. We examined the associations of childhood non-HDL-C and LDL-C levels with adult ASCVD events and determined whether non-HDL-C has better utility than LDL-C in predicting adult ASCVD events. METHODS: This prospective cohort study included 21 126 participants from the i3C Consortium (International Childhood Cardiovascular Cohorts). Proportional hazards regressions were used to estimate the risk for incident fatal and fatal/nonfatal ASCVD events associated with childhood non-HDL-C and LDL-C levels (age- and sex-specific z scores; concordant/discordant categories defined by guideline-recommended cutoffs), adjusted for sex, Black race, cohort, age at and calendar year of child measurement, body mass index, and systolic blood pressure. Predictive utility was determined by the C index. RESULTS: After an average follow-up of 35 years, 153 fatal ASCVD events occurred in 21 126 participants (mean age at childhood visits, 11.9 years), and 352 fatal/nonfatal ASCVD events occurred in a subset of 11 296 participants who could be evaluated for this outcome. Childhood non-HDL-C and LDL-C levels were each associated with higher risk of fatal and fatal/nonfatal ASCVD events (hazard ratio ranged from 1.27 [95% CI, 1.14-1.41] to 1.35 [95% CI, 1.13-1.60] per unit increase in the risk factor z score). Non-HDL-C had better discriminative utility than LDL-C (difference in C index, 0.0054 [95% CI, 0.0006-0.0102] and 0.0038 [95% CI, 0.0008-0.0068] for fatal and fatal/nonfatal events, respectively). The discordant group with elevated non-HDL-C and normal LDL-C had a higher risk of ASCVD events compared with the concordant group with normal non-HDL-C and LDL-C (fatal events: hazard ratio, 1.90 [95% CI, 0.98-3.70]; fatal/nonfatal events: hazard ratio, 1.94 [95% CI, 1.23-3.06]). CONCLUSIONS: Childhood non-HDL-C and LDL-C levels are associated with ASCVD events in midlife. Non-HDL-C is better than LDL-C in predicting adult ASCVD events, particularly among individuals who had normal LDL-C but elevated non-HDL-C. These findings suggest that both non-HDL-C and LDL-C are useful in identifying children at higher risk of ASCVD events, but non-HDL-C may provide added prognostic information when it is discordantly higher than the corresponding LDL-C and has the practical advantage of being determined without a fasting sample.


Asunto(s)
Aterosclerosis , Enfermedades Cardiovasculares , Masculino , Adulto , Femenino , Niño , Humanos , LDL-Colesterol , Estudios Prospectivos , Colesterol , Aterosclerosis/diagnóstico , Aterosclerosis/epidemiología , Lipoproteínas , Factores de Riesgo , HDL-Colesterol
7.
J Cell Sci ; 136(10)2023 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-37218462

RESUMEN

Translation of mRNAs containing premature termination codons (PTCs) results in truncated protein products with deleterious effects. Nonsense-mediated decay (NMD) is a surveillance pathway responsible for detecting PTC containing transcripts. Although the molecular mechanisms governing mRNA degradation have been extensively studied, the fate of the nascent protein product remains largely uncharacterized. Here, we use a fluorescent reporter system in mammalian cells to reveal a selective degradation pathway specifically targeting the protein product of an NMD mRNA. We show that this process is post-translational and dependent on the ubiquitin proteasome system. To systematically uncover factors involved in NMD-linked protein quality control, we conducted genome-wide flow cytometry-based screens. Our screens recovered known NMD factors but suggested that protein degradation did not depend on the canonical ribosome-quality control (RQC) pathway. A subsequent arrayed screen demonstrated that protein and mRNA branches of NMD rely on a shared recognition event. Our results establish the existence of a targeted pathway for nascent protein degradation from PTC containing mRNAs, and provide a reference for the field to identify and characterize required factors.


Asunto(s)
Mamíferos , Degradación de ARNm Mediada por Codón sin Sentido , Animales , Degradación de ARNm Mediada por Codón sin Sentido/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Mamíferos/metabolismo
8.
N Engl J Med ; 386(20): 1877-1888, 2022 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-35373933

RESUMEN

BACKGROUND: Childhood cardiovascular risk factors predict subclinical adult cardiovascular disease, but links to clinical events are unclear. METHODS: In a prospective cohort study involving participants in the International Childhood Cardiovascular Cohort (i3C) Consortium, we evaluated whether childhood risk factors (at the ages of 3 to 19 years) were associated with cardiovascular events in adulthood after a mean follow-up of 35 years. Body-mass index, systolic blood pressure, total cholesterol level, triglyceride level, and youth smoking were analyzed with the use of i3C-derived age- and sex-specific z scores and with a combined-risk z score that was calculated as the unweighted mean of the five risk z scores. An algebraically comparable adult combined-risk z score (before any cardiovascular event) was analyzed jointly with the childhood risk factors. Study outcomes were fatal cardiovascular events and fatal or nonfatal cardiovascular events, and analyses were performed after multiple imputation with the use of proportional-hazards regression. RESULTS: In the analysis of 319 fatal cardiovascular events that occurred among 38,589 participants (49.7% male and 15.0% Black; mean [±SD] age at childhood visits, 11.8±3.1 years), the hazard ratios for a fatal cardiovascular event in adulthood ranged from 1.30 (95% confidence interval [CI], 1.14 to 1.47) per unit increase in the z score for total cholesterol level to 1.61 (95% CI, 1.21 to 2.13) for youth smoking (yes vs. no). The hazard ratio for a fatal cardiovascular event with respect to the combined-risk z score was 2.71 (95% CI, 2.23 to 3.29) per unit increase. The hazard ratios and their 95% confidence intervals in the analyses of fatal cardiovascular events were similar to those in the analyses of 779 fatal or nonfatal cardiovascular events that occurred among 20,656 participants who could be evaluated for this outcome. In the analysis of 115 fatal cardiovascular events that occurred in a subgroup of 13,401 participants (31.0±5.6 years of age at the adult measurement) who had data on adult risk factors, the adjusted hazard ratio with respect to the childhood combined-risk z score was 3.54 (95% CI, 2.57 to 4.87) per unit increase, and the mutually adjusted hazard ratio with respect to the change in the combined-risk z score from childhood to adulthood was 2.88 (95% CI, 2.06 to 4.05) per unit increase. The results were similar in the analysis of 524 fatal or nonfatal cardiovascular events. CONCLUSIONS: In this prospective cohort study, childhood risk factors and the change in the combined-risk z score between childhood and adulthood were associated with cardiovascular events in midlife. (Funded by the National Institutes of Health.).


Asunto(s)
Enfermedades Cardiovasculares , Adolescente , Adulto , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/etiología , Niño , Preescolar , Colesterol , Femenino , Factores de Riesgo de Enfermedad Cardiaca , Humanos , Masculino , Estudios Prospectivos , Factores de Riesgo , Adulto Joven
9.
Development ; 149(10)2022 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-35451473

RESUMEN

Notch signaling promotes maturation of nephron epithelia, but its proposed contribution to nephron segmentation into proximal and distal domains has been called into doubt. We leveraged single cell and bulk RNA-seq, quantitative immunofluorescent lineage/fate tracing, and genetically modified human induced pluripotent stem cells (iPSCs) to revisit this question in developing mouse kidneys and human kidney organoids. We confirmed that Notch signaling is needed for maturation of all nephron lineages, and thus mature lineage markers fail to detect a fate bias. By contrast, early markers identified a distal fate bias in cells lacking Notch2, and a concomitant increase in early proximal and podocyte fates in cells expressing hyperactive Notch1 was observed. Orthogonal support for a conserved role for Notch signaling in the distal/proximal axis segmentation is provided by the demonstration that nicastrin (NCSTN)-deficient human iPSC-derived organoids differentiate into TFA2B+ distal tubule and CDH1+ connecting segment progenitors, but not into HNF4A+ or LTL+ proximal progenitors.


Asunto(s)
Regulación del Desarrollo de la Expresión Génica , Células Madre Pluripotentes Inducidas , Animales , Diferenciación Celular , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Riñón/metabolismo , Ratones , Nefronas/metabolismo , Organogénesis/genética , Receptores Notch/genética , Receptores Notch/metabolismo
10.
Nature ; 574(7778): 390-393, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31597960

RESUMEN

Transition-metal complexes are widely used in the physical and biological sciences. They have essential roles in catalysis, synthesis, materials science, photophysics and bioinorganic chemistry. Our understanding of transition-metal complexes originates from Alfred Werner's realization that their three-dimensional shape influences their properties and reactivity1, and the intrinsic link between shape and electronic structure is now firmly underpinned by molecular-orbital theory2-5. Despite more than a century of advances in this field, the geometries of transition-metal complexes remain limited to a few well-understood examples. The archetypal geometries of six-coordinate transition metals are octahedral and trigonal prismatic, and although deviations from ideal bond angles and bond lengths are frequent6, alternative parent geometries are extremely rare7. The hexagonal planar coordination environment is known, but it is restricted to condensed metallic phases8, the hexagonal pores of coordination polymers9, or clusters that contain more than one transition metal in close proximity10,11. Such a geometry had been considered12,13 for [Ni(PtBu)6]; however, an analysis of the molecular orbitals suggested that this complex is best described as a 16-electron species with a trigonal planar geometry14. Here we report the isolation and structural characterization of a simple coordination complex in which six ligands form bonds with a central transition metal in a hexagonal planar arrangement. The structure contains a central palladium atom surrounded by three hydride and three magnesium-based ligands. This finding has the potential to introduce additional design principles for transition-metal complexes, with implications for several scientific fields.


Asunto(s)
Complejos de Coordinación/química , Metales/química , Complejos de Coordinación/aislamiento & purificación , Ciencia de los Materiales , Conformación Molecular , Elementos de Transición/química
12.
Am J Respir Crit Care Med ; 210(1): 77-86, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38717347

RESUMEN

Rationale: Bronchiectasis is characterized by acute exacerbations, but the biological mechanisms underlying these events are poorly characterized. Objectives: To investigate the inflammatory and microbial characteristics of exacerbations of bronchiectasis. Methods: A total of 120 patients with bronchiectasis were enrolled and presented with acute exacerbations within 12 months. Spontaneous sputum samples were obtained during a period of clinical stability and again at exacerbation before receipt of antibiotic treatment. A validated rapid PCR assay for bacteria and viruses was used to classify exacerbations as bacterial, viral, or both. Sputum inflammatory assessments included label-free liquid chromatography-tandem mass spectrometry and measurement of sputum cytokines and neutrophil elastase activity. 16 s rRNA sequencing was used to characterize the microbiome. Measurements and Main Results: Bronchiectasis exacerbations showed profound molecular heterogeneity. At least one bacterium was identified in 103 samples (86%), and a high bacterial load (total bacterial load > 107 copies/g) was observed in 81 patients (68%). Respiratory viruses were identified in 55 (46%) patients, with rhinovirus being the most common virus (31%). PCR testing was more sensitive than culture. No consistent change in the microbiome was observed at exacerbation. Exacerbations were associated with increased neutrophil elastase, proteinase-3, IL-1ß, and CXCL8. These markers were particularly associated with bacterial and bacterial plus viral exacerbations. Distinct inflammatory and microbiome profiles were seen between different exacerbation subtypes, including bacterial, viral, and eosinophilic events in both hypothesis-led and hypothesis-free analysis using integrated microbiome and proteomics, demonstrating four subtypes of exacerbation. Conclusions: Bronchiectasis exacerbations are heterogeneous events with contributions from bacteria, viruses, and inflammatory dysregulation.


Asunto(s)
Bronquiectasia , Progresión de la Enfermedad , Esputo , Humanos , Bronquiectasia/microbiología , Bronquiectasia/fisiopatología , Masculino , Femenino , Persona de Mediana Edad , Anciano , Esputo/microbiología , Estudios de Cohortes , Elastasa de Leucocito/metabolismo , Microbiota
13.
Am J Respir Crit Care Med ; 210(1): 47-62, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38271608

RESUMEN

Rationale: Chronic infection and inflammation shapes the airway microbiome in bronchiectasis. Utilizing whole-genome shotgun metagenomics to analyze the airway resistome provides insight into interplay between microbes, resistance genes, and clinical outcomes. Objectives: To apply whole-genome shotgun metagenomics to the airway microbiome in bronchiectasis to highlight a diverse pool of antimicrobial resistance genes: the "resistome," the clinical significance of which remains unclear. Methods: Individuals with bronchiectasis were prospectively recruited into cross-sectional and longitudinal cohorts (n = 280), including the international multicenter cross-sectional Cohort of Asian and Matched European Bronchiectasis 2 (CAMEB 2) study (n = 251) and two independent cohorts, one describing patients experiencing acute exacerbation and a further cohort of patients undergoing Pseudomonas aeruginosa eradication treatment. Sputum was subjected to metagenomic sequencing, and the bronchiectasis resistome was evaluated in association with clinical outcomes and underlying host microbiomes. Measurements and Main Results: The bronchiectasis resistome features a unique resistance gene profile and increased counts of aminoglycoside, bicyclomycin, phenicol, triclosan, and multidrug resistance genes. Longitudinally, it exhibits within-patient stability over time and during exacerbations despite between-patient heterogeneity. Proportional differences in baseline resistome profiles, including increased macrolide and multidrug resistance genes, associate with shorter intervals to the next exacerbation, whereas distinct resistome archetypes associate with frequent exacerbations, poorer lung function, geographic origin, and the host microbiome. Unsupervised analysis of resistome profiles identified two clinically relevant "resistotypes," RT1 and RT2, the latter characterized by poor clinical outcomes, increased multidrug resistance, and P. aeruginosa. Successful targeted eradication in P. aeruginosa-colonized individuals mediated reversion from RT2 to RT1, a more clinically favorable resistome profile demonstrating reduced resistance gene diversity. Conclusions: The bronchiectasis resistome associates with clinical outcomes, geographic origin, and the underlying host microbiome. Bronchiectasis resistotypes link to clinical disease and are modifiable through targeted antimicrobial therapy.


Asunto(s)
Bronquiectasia , Bronquiectasia/fisiopatología , Bronquiectasia/microbiología , Bronquiectasia/tratamiento farmacológico , Humanos , Masculino , Femenino , Persona de Mediana Edad , Anciano , Estudios Transversales , Estudios Longitudinales , Antibacterianos/uso terapéutico , Estudios Prospectivos , Microbiota/genética , Pseudomonas aeruginosa/genética , Esputo/microbiología , Metagenómica/métodos , Adulto , Infecciones por Pseudomonas/tratamiento farmacológico , Infecciones por Pseudomonas/complicaciones
14.
Proc Natl Acad Sci U S A ; 119(27): e2115538119, 2022 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-35759666

RESUMEN

Blue cone monochromacy (BCM) is an X-linked retinal disorder characterized by low vision, photoaversion, and poor color discrimination. BCM is due to the lack of long-wavelength-sensitive and middle-wavelength-sensitive cone photoreceptor function and caused by mutations in the OPN1LW/OPN1MW gene cluster on Xq28. Here, we investigated the prevalence and the landscape of submicroscopic structural variants (SVs) at single-base resolution in BCM patients. We found that about one-third (n = 73) of the 213 molecularly confirmed BCM families carry an SV, most commonly deletions restricted to the OPN1LW/OPN1MW gene cluster. The structure and precise breakpoints of the SVs were resolved in all but one of the 73 families. Twenty-two families-all from the United States-showed the same SV, and we confirmed a common ancestry of this mutation. In total, 42 distinct SVs were identified, including 40 previously unreported SVs, thereby quadrupling the number of precisely mapped SVs underlying BCM. Notably, there was no "region of overlap" among these SVs. However, 90% of SVs encompass the upstream locus control region, an essential enhancer element. Its minimal functional extent based on deletion mapping in patients was refined to 358 bp. Breakpoint analyses suggest diverse mechanisms underlying SV formation as well as in one case the gene conversion-based exchange of a 142-bp deletion between opsin genes. Using parsimonious assumptions, we reconstructed the composition and copy number of the OPN1LW/OPN1MW gene cluster prior to the mutation event and found evidence that large gene arrays may be predisposed to the occurrence of SVs at this locus.


Asunto(s)
Defectos de la Visión Cromática , Opsinas de Bastones , Defectos de la Visión Cromática/genética , Eliminación de Gen , Humanos , Familia de Multigenes/genética , Células Fotorreceptoras Retinianas Conos , Opsinas de Bastones/genética
15.
Br J Cancer ; 130(6): 897-907, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38191608

RESUMEN

Urothelial carcinoma (UC) is a common cancer associated with a poor prognosis in patients with advanced disease. Platinum-based chemotherapy has remained the cornerstone of systemic anticancer treatment for many years, and recent developments in the treatment landscape have improved outcomes. In this review, we provide an overview of systemic treatment for UC, including clinical data supporting the current standard of care at each point in the treatment pathway and author interpretations from a UK perspective. Neoadjuvant cisplatin-based chemotherapy is recommended for eligible patients with muscle-invasive bladder cancer and is preferable to adjuvant treatment. For first-line treatment of advanced UC, platinum-eligible patients should receive cisplatin- or carboplatin-based chemotherapy, followed by avelumab maintenance in those without disease progression. Among patients unable to receive platinum-based chemotherapy, immune checkpoint inhibitor (ICI) treatment is an option for those with programmed death ligand 1 (PD-L1)-positive tumours. Second-line or later treatment options depend on prior treatment, and enfortumab vedotin is preferred after prior ICI and chemotherapy, although availability varies between countries. Additional options include rechallenge with platinum-based chemotherapy, an ICI, or non-platinum-based chemotherapy. Areas of uncertainty include the optimal number of first-line chemotherapy cycles for advanced UC and the value of PD-L1 testing for UC.


Asunto(s)
Antineoplásicos Inmunológicos , Carcinoma de Células Transicionales , Neoplasias de la Vejiga Urinaria , Humanos , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Neoplasias de la Vejiga Urinaria/patología , Carcinoma de Células Transicionales/tratamiento farmacológico , Carcinoma de Células Transicionales/patología , Cisplatino , Antígeno B7-H1 , Platino (Metal)/uso terapéutico , Reino Unido , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico
16.
Anal Chem ; 96(18): 7047-7055, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38653469

RESUMEN

Raman spectroscopy can provide nonbiased single-cell analysis based on the endogenous ensemble of biomolecules, with alterations in cellular content indicative of cell state and disease. The measurements themselves can be performed in a variety of modes: generally, full imaging takes the most time but can provide the most information. By reducing the imaging resolution and generating the most characteristic single-cell Raman spectrum in the shortest time, we optimize the utility of the Raman measurement for cell phenotyping. Here, we establish methods to compare these different measurement approaches and assess what, if any, undesired effects occur in the cell. Assuming that laser-induced damage should be apparent as a change in molecular spectra across sequential measurements, and by defining the information content as the Raman-based separability of two cell lines, we thereby establish a parameter range for optimum measurement sensitivity and single-cell throughput in single-cell Raman spectroscopic analysis. While the work here uses 532 nm irradiation, the same approach can be generalized to Raman analysis at other wavelengths.


Asunto(s)
Análisis de la Célula Individual , Espectrometría Raman , Espectrometría Raman/métodos , Análisis de la Célula Individual/métodos , Humanos , Fenotipo , Ensayos Analíticos de Alto Rendimiento
17.
Development ; 148(9)2021 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-33982759

RESUMEN

Genetic screens are designed to target individual genes for the practical reason of establishing a clear association between a mutant phenotype and a single genetic locus. This allows for a developmental or physiological role to be assigned to the wild-type gene. We previously observed that the concurrent loss of Pax6 and Polycomb epigenetic repressors in Drosophila leads the eye to transform into a wing. This fate change is not seen when either factor is disrupted separately. An implication of this finding is that standard screens may miss the roles that combinations of genes play in development. Here, we show that this phenomenon is not limited to Pax6 and Polycomb but rather applies more generally. We demonstrate that in the Drosophila eye-antennal disc, the simultaneous downregulation of Pax6 with either the NURF nucleosome remodeling complex or the Pointed transcription factor transforms the head epidermis into an antenna. This is a previously unidentified fate change that is also not observed with the loss of individual genes. We propose that the use of multi-gene knockdowns is an essential tool for unraveling the complexity of development.


Asunto(s)
Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila/fisiología , Factor de Transcripción PAX6/genética , Factor de Transcripción PAX6/metabolismo , Animales , Epidermis , Ojo/citología , Ojo/metabolismo , Regulación del Desarrollo de la Expresión Génica , Técnicas de Silenciamiento del Gen , Larva , Nucleosomas , Proteínas del Grupo Polycomb/genética , Factores de Transcripción/metabolismo
18.
Eur Respir J ; 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38811046

RESUMEN

RATIONALE: The inflammasome is a key regulatory complex of the inflammatory response leading to IL-1ß release and activation. IL-1ß amplifies inflammatory responses and induces mucus secretion and hyperconcentration in other diseases. The role of IL-1ß in bronchiectasis has not been investigated. OBJECTIVES: To characterize the role of airway IL-1ß in bronchiectasis including the association with mucus properties, ciliary function, airway inflammation, microbiome and disease severity. METHODS: Stable bronchiectasis patients were enrolled in an international cohort study (n=269). IL-1ß was measured in sputum supernatant. A validation cohort also had sputum rheology and hydration measured (n=53). For analysis, patients were stratified according to the median value of IL-1ß in the population (High versus Low) to compare disease severity, airway infection, microbiome (16S rRNA sequencing), inflammation and caspase-1 activity. Primary human nasal epithelial cells grown in air-liquid interface culture were used to study IL-1ß effect on cilia function. MEASUREMENTS AND MAIN RESULTS: Patients with high sputum IL-1ß had more severe disease, increased caspase-1 activity and increased Th1, Th2 and neutrophil inflammatory response compared with patients with low IL-1ß. The active-dominant form of IL-1ß was associated with increased disease severity. High IL-1ß was related to higher relative abundance of Proteobacteria in the microbiome and increased mucus solid content and viscoelastic properties. Chronic IL-1ß treatment reduced the functionality of cilia and tight junctions of epithelial cells in-vitro. CONCLUSIONS: A subset of stable bronchiectasis patients show increased airway IL-1ß, suggesting pulmonary inflammasome activation is linked with more severe disease, airway infection, mucus dehydration and epithelial dysfunction.

19.
HIV Med ; 25(6): 746-753, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38433523

RESUMEN

OBJECTIVES: This qualitative sub-study aimed to explore how cisgender gay, bisexual, and other men who have sex with men (cis-GBMSM) and transgender people who reported non-consensual sex (NCS) accessed health care services, what barriers they faced, and how this experience influenced subsequent HIV testing. METHODS: SELPHI is an online randomized controlled trial evaluating both acceptability and efficiency of HIV-self testing among cis-GBMSM and transgender people. Semi-structured interviews were conducted, audio-recorded, transcribed, and analysed through a framework analysis, as a qualitative sub-study. We identified narratives of NCS from interviews and investigated experiences of cis-GBMSM and transgender people accessing health care services following sexual assault. RESULTS: Of 95 participants, 15 (16%) spontaneously reported NCS. Participants reported a broad range of NCS, including partner's coercive behaviours, non-consensual removal of condoms, and rapes. All feared HIV transmission, leading them to test for HIV, underlining a marked lack of awareness of post-exposure prophylaxis (PEP). Most had negative experiences in communicating with reception staff in sexual health clinics following these incidents. A lack of confidentiality and empathy was described in these situations of psychological distress. Clinic visits were primarily focused on testing for HIV and sexually transmitted infection, and generally no specific psychological support was offered. Getting a negative HIV result was a key step in regaining control for people who experienced NCS. CONCLUSIONS: Sexual health care providers should take care to more fully address the issue of NCS with cis-GBMSM and transgender people when it arises. Recognizing and managing the emotional impact of NCS on affected patients would prevent negative experiences and increase confidence in care.


Asunto(s)
Infecciones por VIH , Prueba de VIH , Delitos Sexuales , Humanos , Masculino , Adulto , Infecciones por VIH/prevención & control , Infecciones por VIH/diagnóstico , Infecciones por VIH/psicología , Delitos Sexuales/psicología , Adulto Joven , Persona de Mediana Edad , Investigación Cualitativa , Minorías Sexuales y de Género/psicología , Aceptación de la Atención de Salud/psicología , Aceptación de la Atención de Salud/estadística & datos numéricos , Personas Transgénero/psicología , Entrevistas como Asunto , Homosexualidad Masculina/psicología , Adolescente
20.
J Pediatr ; 264: 113778, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37848085

RESUMEN

High cardiorespiratory fitness (CRF) in adulthood is important for survival from major chronic diseases and preserving good health. We examined how childhood CRF tracks, or persists, into adulthood. Among a cohort of 748 school children followed over 34 years, we found child CRF correlated with young- (r = 0.30) and mid-adulthood (r = 0.16) CRF.


Asunto(s)
Capacidad Cardiovascular , Humanos , Niño , Aptitud Física
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