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1.
Nat Immunol ; 21(11): 1336-1345, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32887977

RESUMEN

The development of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines and therapeutics will depend on understanding viral immunity. We studied T cell memory in 42 patients following recovery from COVID-19 (28 with mild disease and 14 with severe disease) and 16 unexposed donors, using interferon-γ-based assays with peptides spanning SARS-CoV-2 except ORF1. The breadth and magnitude of T cell responses were significantly higher in severe as compared with mild cases. Total and spike-specific T cell responses correlated with spike-specific antibody responses. We identified 41 peptides containing CD4+ and/or CD8+ epitopes, including six immunodominant regions. Six optimized CD8+ epitopes were defined, with peptide-MHC pentamer-positive cells displaying the central and effector memory phenotype. In mild cases, higher proportions of SARS-CoV-2-specific CD8+ T cells were observed. The identification of T cell responses associated with milder disease will support an understanding of protective immunity and highlights the potential of including non-spike proteins within future COVID-19 vaccine design.


Asunto(s)
Antígenos Virales/inmunología , Betacoronavirus/inmunología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Memoria Inmunológica/inmunología , COVID-19 , Vacunas contra la COVID-19 , Infecciones por Coronavirus/inmunología , Infecciones por Coronavirus/patología , Infecciones por Coronavirus/prevención & control , Epítopos de Linfocito T/inmunología , Humanos , Epítopos Inmunodominantes/inmunología , Pandemias , Neumonía Viral/inmunología , Neumonía Viral/patología , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus/inmunología , Reino Unido , Vacunas Virales/inmunología
2.
Cell ; 157(7): 1644-1656, 2014 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-24949974

RESUMEN

Because apoptosis of infected cells can limit virus production and spread, some viruses have co-opted prosurvival genes from the host. This includes the Epstein-Barr virus (EBV) gene BHRF1, a homolog of human Bcl-2 proteins that block apoptosis and are associated with cancer. Computational design and experimental optimization were used to generate a novel protein called BINDI that binds BHRF1 with picomolar affinity. BINDI recognizes the hydrophobic cleft of BHRF1 in a manner similar to other Bcl-2 protein interactions but makes many additional contacts to achieve exceptional affinity and specificity. BINDI induces apoptosis in EBV-infected cancer lines, and when delivered with an antibody-targeted intracellular delivery carrier, BINDI suppressed tumor growth and extended survival in a xenograft disease model of EBV-positive human lymphoma. High-specificity-designed proteins that selectively kill target cells may provide an advantage over the toxic compounds used in current generation antibody-drug conjugates.


Asunto(s)
Herpesvirus Humano 4/química , Ingeniería de Proteínas , Proteínas/farmacología , Proteínas Virales/antagonistas & inhibidores , Secuencia de Aminoácidos , Animales , Apoptosis/efectos de los fármacos , Biología Computacional , Cristalografía por Rayos X , Infecciones por Virus de Epstein-Barr/tratamiento farmacológico , Herpesvirus Humano 4/fisiología , Xenoinjertos , Humanos , Linfoma de Células B/tratamiento farmacológico , Ratones , Modelos Moleculares , Datos de Secuencia Molecular , Trasplante de Neoplasias , Proteínas/química , Proteínas/metabolismo , Alineación de Secuencia , Proteínas Virales/química
3.
Nature ; 620(7972): 218-225, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37438532

RESUMEN

Retrotransposons are highly enriched in the animal genome1-3. The activation of retrotransposons can rewrite host DNA information and fundamentally impact host biology1-3. Although developmental activation of retrotransposons can offer benefits for the host, such as against virus infection, uncontrolled activation promotes disease or potentially drives ageing1-5. After activation, retrotransposons use their mRNA as templates to synthesize double-stranded DNA for making new insertions in the host genome1-3,6. Although the reverse transcriptase that they encode can synthesize the first-strand DNA1-3,6, how the second-strand DNA is generated remains largely unclear. Here we report that retrotransposons hijack the alternative end-joining (alt-EJ) DNA repair process of the host for a circularization step to synthesize their second-strand DNA. We used Nanopore sequencing to examine the fates of replicated retrotransposon DNA, and found that 10% of them achieve new insertions, whereas 90% exist as extrachromosomal circular DNA (eccDNA). Using eccDNA production as a readout, further genetic screens identified factors from alt-EJ as essential for retrotransposon replication. alt-EJ drives the second-strand synthesis of the long terminal repeat retrotransposon DNA through a circularization process and is therefore necessary for eccDNA production and new insertions. Together, our study reveals that alt-EJ is essential in driving the propagation of parasitic genomic retroelements. Our study uncovers a conserved function of this understudied DNA repair process, and provides a new perspective to understand-and potentially control-the retrotransposon life cycle.


Asunto(s)
Reparación del ADN por Unión de Extremidades , Replicación del ADN , ADN Circular , Parásitos , Retroelementos , Animales , Retroelementos/genética , ADN Polimerasa Dirigida por ARN/genética , ADN Polimerasa Dirigida por ARN/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Moldes Genéticos , ADN Circular/biosíntesis , ADN Circular/genética , ADN Circular/metabolismo , ADN de Cadena Simple/biosíntesis , ADN de Cadena Simple/genética , ADN de Cadena Simple/metabolismo , Parásitos/genética , Genoma/genética
4.
Nature ; 617(7960): 409-416, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37138077

RESUMEN

CrAssphage and related viruses of the order Crassvirales (hereafter referred to as crassviruses) were originally discovered by cross-assembly of metagenomic sequences. They are the most abundant viruses in the human gut, are found in the majority of individual gut viromes, and account for up to 95% of the viral sequences in some individuals1-4. Crassviruses are likely to have major roles in shaping the composition and functionality of the human microbiome, but the structures and roles of most of the virally encoded proteins are unknown, with only generic predictions resulting from bioinformatic analyses4,5. Here we present a cryo-electron microscopy reconstruction of Bacteroides intestinalis virus ΦcrAss0016, providing the structural basis for the functional assignment of most of its virion proteins. The muzzle protein forms an assembly about 1 MDa in size at the end of the tail and exhibits a previously unknown fold that we designate the 'crass fold', that is likely to serve as a gatekeeper that controls the ejection of cargos. In addition to packing the approximately 103 kb of virus DNA, the ΦcrAss001 virion has extensive storage space for virally encoded cargo proteins in the capsid and, unusually, within the tail. One of the cargo proteins is present in both the capsid and the tail, suggesting a general mechanism for protein ejection, which involves partial unfolding of proteins during their extrusion through the tail. These findings provide a structural basis for understanding the mechanisms of assembly and infection of these highly abundant crassviruses.


Asunto(s)
Virus ADN , Intestinos , Proteínas Virales , Virión , Humanos , Cápside/química , Cápside/metabolismo , Cápside/ultraestructura , Microscopía por Crioelectrón , Virus ADN/química , Virus ADN/clasificación , Virus ADN/aislamiento & purificación , Virus ADN/metabolismo , Virus ADN/ultraestructura , Virión/química , Virión/metabolismo , Virión/ultraestructura , Ensamble de Virus , Intestinos/microbiología , Intestinos/virología , Proteínas Virales/química , Proteínas Virales/metabolismo , Proteínas Virales/ultraestructura , Desplegamiento Proteico , Pliegue de Proteína
5.
Nature ; 621(7978): 312-317, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37532941

RESUMEN

The balance between degradation and preservation of sedimentary organic carbon (OC) is important for global carbon and oxygen cycles1. The relative importance of different mechanisms and environmental conditions contributing to marine sedimentary OC preservation, however, remains unclear2-8. Simple organic molecules can be geopolymerized into recalcitrant forms by means of the Maillard reaction5, although reaction kinetics at marine sedimentary temperatures are thought to be slow9,10. More recent work in terrestrial systems suggests that the reaction can be catalysed by manganese minerals11-13, but the potential for the promotion of geopolymerized OC formation at marine sedimentary temperatures is uncertain. Here we present incubation experiments and find that iron and manganese ions and minerals abiotically catalyse the Maillard reaction by up to two orders of magnitude at temperatures relevant to continental margins where most preservation occurs4. Furthermore, the chemical signature of the reaction products closely resembles dissolved and total OC found in continental margin sediments globally. With the aid of a pore-water model14, we estimate that iron- and manganese-catalysed transformation of simple organic molecules into complex macromolecules might generate on the order of approximately 4.1 Tg C yr-1 for preservation in marine sediments. In the context of perhaps only about 63 Tg C yr-1 variation in sedimentary organic preservation over the past 300 million years6, we propose that variable iron and manganese inputs to the ocean could exert a substantial but hitherto unexplored impact on global OC preservation over geological time.

6.
Cell ; 155(2): 296-307, 2013 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-24120131

RESUMEN

Robust dendrite morphogenesis is a critical step in the development of reproducible neural circuits. However, little is known about the extracellular cues that pattern complex dendrite morphologies. In the model nematode Caenorhabditis elegans, the sensory neuron PVD establishes stereotypical, highly branched dendrite morphology. Here, we report the identification of a tripartite ligand-receptor complex of membrane adhesion molecules that is both necessary and sufficient to instruct spatially restricted growth and branching of PVD dendrites. The ligand complex SAX-7/L1CAM and MNR-1 function at defined locations in the surrounding hypodermal tissue, whereas DMA-1 acts as the cognate receptor on PVD. Mutations in this complex lead to dramatic defects in the formation, stabilization, and organization of the dendritic arbor. Ectopic expression of SAX-7 and MNR-1 generates a predictable, unnaturally patterned dendritic tree in a DMA-1-dependent manner. Both in vivo and in vitro experiments indicate that all three molecules are needed for interaction.


Asunto(s)
Proteínas de Caenorhabditis elegans/metabolismo , Dendritas/metabolismo , Proteínas de la Membrana/metabolismo , Moléculas de Adhesión de Célula Nerviosa/metabolismo , Neurogénesis , Animales , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Fibronectinas/metabolismo , Proteínas de la Membrana/genética , Moléculas de Adhesión de Célula Nerviosa/genética , Filogenia
7.
Proc Natl Acad Sci U S A ; 120(4): e2200057120, 2023 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-36649432

RESUMEN

Antibody delivery to the CNS remains a huge hurdle for the clinical application of antibodies targeting a CNS antigen. The blood-brain barrier and blood-CSF barrier restrict access of therapeutic antibodies to their CNS targets in a major way. The very high amounts of therapeutic antibodies that are administered systemically in recent clinical trials to reach CNS targets are barely viable cost-wise for broad, routine applications. Though global CNS delivery of antibodies can be achieved by intrathecal application, these procedures are invasive. A non-invasive method to bring antibodies into the CNS reliably and reproducibly remains an important unmet need in neurology. In the present study, we show that intranasal application of a mouse monoclonal antibody against the neurite growth-inhibiting and plasticity-restricting membrane protein Nogo-A leads to a rapid transfer of significant amounts of antibody to the brain and spinal cord in intact adult rats. Daily intranasal application for 2 wk of anti-Nogo-A antibody enhanced growth and compensatory sprouting of corticofugal projections and functional recovery in rats after large unilateral cortical strokes. These findings are a starting point for clinical translation for a less invasive route of application of therapeutic antibodies to CNS targets for many neurological indications.


Asunto(s)
Anticuerpos Monoclonales , Proteínas de la Mielina , Animales , Ratas , Encéfalo/metabolismo , Proteínas de la Mielina/metabolismo , Proteínas Nogo , Médula Espinal/metabolismo , Anticuerpos Monoclonales/administración & dosificación , Administración Intranasal
8.
Am J Respir Crit Care Med ; 210(3): 298-310, 2024 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-38315959

RESUMEN

Rationale: Progressive lung function loss is recognized in chronic obstructive pulmonary disease (COPD); however, no study concurrently evaluates how accelerated lung function decline relates to mucus properties and the microbiome in COPD. Objectives: Longitudinal assessment of mucus and microbiome changes accompanying accelerated lung function decline in patients COPD. Methods: This was a prospective, longitudinal assessment of the London COPD cohort exhibiting the greatest FEV1 decline (n = 30; accelerated decline; 156 ml/yr FEV1 loss) and with no FEV1 decline (n = 28; nondecline; 49 ml/yr FEV1 gain) over time. Lung microbiomes from paired sputum (total 116 specimens) were assessed by shotgun metagenomics and corresponding mucus profiles evaluated for biochemical and biophysical properties. Measurements and Main Results: Biochemical and biophysical mucus properties are significantly altered in the accelerated decline group. Unsupervised principal component analysis showed clear separation, with mucus biochemistry associated with accelerated decline, whereas biophysical mucus characteristics contributed to interindividual variability. When mucus and microbes are considered together, an accelerated decline mucus-microbiome association emerges, characterized by increased mucin (MUC5AC [mucin 5AC] and MUC5B [mucin 5B]) concentration and the presence of Achromobacter and Klebsiella. As COPD progresses, mucus-microbiome shifts occur, initially characterized by low mucin concentration and transition from viscous to elastic dominance accompanied by the commensals Veillonella, Gemella, Rothia, and Prevotella (Global Initiative for Chronic Obstructive Lung Disease [GOLD] A and B) before transition to increased mucus viscosity, mucins, and DNA concentration together with the emergence of pathogenic microorganisms including Haemophilus, Moraxella, and Pseudomonas (GOLD E). Conclusions: Mucus-microbiome associations evolve over time with accelerated lung function decline, symptom progression, and exacerbations affording fresh therapeutic opportunities for early intervention.


Asunto(s)
Microbiota , Moco , Enfermedad Pulmonar Obstructiva Crónica , Esputo , Humanos , Enfermedad Pulmonar Obstructiva Crónica/microbiología , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Masculino , Femenino , Anciano , Persona de Mediana Edad , Estudios Prospectivos , Esputo/microbiología , Moco/microbiología , Estudios Longitudinales , Progresión de la Enfermedad , Mucina 5B/metabolismo , Volumen Espiratorio Forzado , Mucina 5AC/metabolismo , Londres
9.
Nucleic Acids Res ; 51(13): 7025-7035, 2023 07 21.
Artículo en Inglés | MEDLINE | ID: mdl-37293963

RESUMEN

Double-stranded DNA viruses utilise machinery, made of terminase proteins, to package viral DNA into the capsid. For cos bacteriophage, a defined signal, recognised by small terminase, flanks each genome unit. Here we present the first structural data for a cos virus DNA packaging motor, assembled from the bacteriophage HK97 terminase proteins, procapsids encompassing the portal protein, and DNA containing a cos site. The cryo-EM structure is consistent with the packaging termination state adopted after DNA cleavage, with DNA density within the large terminase assembly ending abruptly at the portal protein entrance. Retention of the large terminase complex after cleavage of the short DNA substrate suggests that motor dissociation from the capsid requires headful pressure, in common with pac viruses. Interestingly, the clip domain of the 12-subunit portal protein does not adhere to C12 symmetry, indicating asymmetry induced by binding of the large terminase/DNA. The motor assembly is also highly asymmetric, showing a ring of 5 large terminase monomers, tilted against the portal. Variable degrees of extension between N- and C-terminal domains of individual subunits suggest a mechanism of DNA translocation driven by inter-domain contraction and relaxation.


Asunto(s)
Bacteriófagos , Ensamble de Virus , Bacteriófagos/genética , Bacteriófagos/metabolismo , Cápside/metabolismo , Proteínas de la Cápside/genética , Proteínas de la Cápside/química , Empaquetamiento del ADN , ADN Viral/genética , Endodesoxirribonucleasas/metabolismo
10.
Pflugers Arch ; 476(2): 243-256, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37993748

RESUMEN

Motility of detrusor smooth muscle includes adrenergic relaxation and cholinergic contraction. Since the latter may be deregulated in overactive bladder (OAB) pathophysiology, anticholinergics are the standard therapy but occasionally less tolerated due to side effects such as dry mouth and constipation. ß3 adrenoceptor agonists also alleviate OAB symptoms by relaxing the detrusor muscle. Their age dependence, however, is far from understood. To address this issue, we induced contractions with KCl (60 mM) and carbachol (from 10 nM to 100 µM) in the presence of the ß3 adrenoceptor agonist CL316,243 (from 0.1 to 10 µM) in both human and rat muscle strips. Our results confirmed that both contractions were attenuated by ß3 adrenoceptor activation in both species, but with differing age dependence. In humans, specimens from mid-life subjects showed a significantly more pronounced effect of CL316,243 in attenuating carbachol-induced contractions than those from aged subjects (Cohen's d of maximal attenuation: 1.82 in mid-life versus 0.13 in aged) without altering EC50. Conversely, attenuation of KCl responses by CL316,243 increased during ageing (Spearman correlation coefficient = -0.584, P<0.01). In rats, both KCl- and carbachol-induced contractions were significantly more attenuated by CL316,243 in samples from adolescent as compared to aged samples. Immunohistochemistry in human detrusor sections proved ß3 adrenoreceptor abundance to remain unaltered during ageing. In conclusion, our findings suggest differential age-dependent changes in human ß3 adrenoceptor-dependent attenuation of detrusor contraction in terms of electromechanical versus pharmacomechanical coupling; they may help understand the differential responsiveness of OAB patients to ß3 agents.


Asunto(s)
Dioxoles , Vejiga Urinaria Hiperactiva , Vejiga Urinaria , Adolescente , Humanos , Ratas , Animales , Anciano , Carbacol/farmacología , Agonistas de Receptores Adrenérgicos beta 3/farmacología , Músculo Liso , Vejiga Urinaria Hiperactiva/tratamiento farmacológico , Receptores Adrenérgicos , Contracción Muscular
11.
Anal Chem ; 96(28): 11181-11188, 2024 07 16.
Artículo en Inglés | MEDLINE | ID: mdl-38967089

RESUMEN

The COVID-19 pandemic has highlighted the need for rapid and reliable diagnostics that are accessible in resource-limited settings. To address this pressing issue, we have developed a rapid, portable, and electricity-free method for extracting nucleic acids from respiratory swabs (i.e. nasal, nasopharyngeal and buccal swabs), successfully demonstrating its effectiveness for the detection of SARS-CoV-2 in residual clinical specimens. Unlike traditional approaches, our solution eliminates the need for micropipettes or electrical equipment, making it user-friendly and requiring little to no training. Our method builds upon the principles of magnetic bead extraction and revolves around a low-cost plastic magnetic lid, called SmartLid, in combination with a simple disposable kit containing all required reagents conveniently prealiquoted. Here, we clinically validated the SmartLid sample preparation method in comparison to the gold standard QIAamp Viral RNA Mini Kit from QIAGEN, using 406 clinical isolates, including 161 SARS-CoV-2 positives, using the SARS-CoV-2 RT-qPCR assays developed by the US Centers for Disease Control and Prevention (CDC). The SmartLid method showed an overall sensitivity of 95.03% (95% CI: 90.44-97.83%) and a specificity of 99.59% (95% CI: 97.76-99.99%), with a positive agreement of 97.79% (95% CI: 95.84-98.98%) when compared to QIAGEN's column-based extraction method. There are clear benefits to using the SmartLid sample preparation kit: it enables swift extraction of viral nucleic acids, taking less than 5 min, without sacrificing significant accuracy when compared to more expensive and time-consuming alternatives currently available on the market. Moreover, its simplicity makes it particularly well-suited for the point-of-care where rapid results and portability are crucial. By providing an efficient and accessible means of nucleic acid extraction, our approach aims to introduce a step-change in diagnostic capabilities for resource-limited settings.


Asunto(s)
COVID-19 , ARN Viral , SARS-CoV-2 , Humanos , SARS-CoV-2/aislamiento & purificación , SARS-CoV-2/genética , COVID-19/diagnóstico , COVID-19/virología , ARN Viral/aislamiento & purificación , ARN Viral/análisis , Prueba de Ácido Nucleico para COVID-19/métodos , Prueba de Ácido Nucleico para COVID-19/instrumentación , Manejo de Especímenes/métodos , Prueba de COVID-19/métodos , Prueba de COVID-19/instrumentación , Técnicas de Diagnóstico Molecular/métodos , Configuración de Recursos Limitados
12.
Artículo en Inglés | MEDLINE | ID: mdl-39347888

RESUMEN

PURPOSE: Exercise offers various clinical benefits to older breast cancer survivors. However, studies report that healthcare providers may not regularly discuss exercise with their patients. We evaluated clinical and sociodemographic determinants of receiving advice about exercise from healthcare providers among older breast cancer survivors (aged ≥65 years). METHODS: We used data from the Surveillance, Epidemiology, and End Results cancer registries linked to the Medicare Health Outcomes Survey (MHOS) from 2008 to 2015. We included female breast cancer survivors, aged ≥65 years, who completed the MHOS survey ≥2 years after a breast cancer diagnosis in a modified Poisson regression to identify clinical and sociodemographic determinants of reportedly receiving advice about exercise from healthcare providers. RESULTS: The sample included 1,836 breast cancer survivors. The median age of the sample was 76 years (range: 72-81). Overall, 10.7% of the survivors were non-Hispanic Black, 10.1% were Hispanic, and 69.3% were non-Hispanic White. Only 52.3% reported receiving advice about exercise from a healthcare provider. Higher body mass index (BMI) and comorbid medical history that included diabetes, cardiovascular, or musculoskeletal disease were each associated with a higher likelihood of receiving exercise advice. Lower education levels, lower BMI, and never having been married were each associated with a lower likelihood of receiving exercise advice. CONCLUSIONS: Nearly half of breast cancer survivors aged ≥65 years did not report receiving exercise advice from a healthcare provider, suggesting interventions are needed to improve exercise counseling between providers and survivors, especially with women with lower educational attainment who have never been married.

13.
J Gen Intern Med ; 39(3): 428-439, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38010458

RESUMEN

BACKGROUND: Guidelines recommend shared decision-making (SDM) around mammography screening for women ≥ 75 years old. OBJECTIVE: To use microsimulation modeling to estimate the lifetime benefits and harms of screening women aged 75, 80, and 85 years based on their individual risk factors (family history, breast density, prior biopsy) and comorbidity level to support SDM in clinical practice. DESIGN, SETTING, AND PARTICIPANTS: We adapted two established Cancer Intervention and Surveillance Modeling Network (CISNET) models to evaluate the remaining lifetime benefits and harms of screening U.S. women born in 1940, at decision ages 75, 80, and 85 years considering their individual risk factors and comorbidity levels. Results were summarized for average- and higher-risk women (defined as having breast cancer family history, heterogeneously dense breasts, and no prior biopsy, 5% of the population). MAIN OUTCOMES AND MEASURES: Remaining lifetime breast cancers detected, deaths (breast cancer/other causes), false positives, and overdiagnoses for average- and higher-risk women by age and comorbidity level for screening (one or five screens) vs. no screening per 1000 women. RESULTS: Compared to stopping, one additional screen at 75 years old resulted in six and eight more breast cancers detected (10% overdiagnoses), one and two fewer breast cancer deaths, and 52 and 59 false positives per 1000 average- and higher-risk women without comorbidities, respectively. Five additional screens over 10 years led to 23 and 31 additional breast cancer cases (29-31% overdiagnoses), four and 15 breast cancer deaths avoided, and 238 and 268 false positives per 1000 average- and higher-risk screened women without comorbidities, respectively. Screening women at older ages (80 and 85 years old) and high comorbidity levels led to fewer breast cancer deaths and a higher percentage of overdiagnoses. CONCLUSIONS: Simulation models show that continuing screening in women ≥ 75 years old results in fewer breast cancer deaths but more false positive tests and overdiagnoses. Together, clinicians and 75 + women may use model output to weigh the benefits and harms of continued screening.


Asunto(s)
Neoplasias de la Mama , Mamografía , Femenino , Humanos , Anciano de 80 o más Años , Anciano , Mamografía/efectos adversos , Mamografía/métodos , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/epidemiología , Mama , Densidad de la Mama , Simulación por Computador , Detección Precoz del Cáncer/efectos adversos , Detección Precoz del Cáncer/métodos , Tamizaje Masivo/efectos adversos , Tamizaje Masivo/métodos
14.
BMC Cancer ; 24(1): 975, 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39118050

RESUMEN

BACKGROUND: A recent trial showed that postmenopausal women diagnosed with hormone receptor-positive, human epidermal growth factor receptor-2 (HER2)-negative, lymph node-positive (1-3 nodes) breast cancer with a 21-gene recurrence score of ≤ 25 could safely omit chemotherapy. However, there are limited data on population-level long-term outcomes associated with omitting chemotherapy among diverse women seen in real-world practice. METHODS: We adapted an established, validated simulation model to generate the joint distributions of population-level characteristics of women diagnosed with early-stage breast cancer in the U.S. Input parameters were derived from cancer registry, meta-analyses, and clinical trial data. The effects of omitting chemotherapy on 10-year distant recurrence-free survival, life-years, and quality adjusted life-years (QALYs) were modeled for premenopausal and postmenopausal women. QALYs were discounted at 3%. Results were evaluated for subgroups stratified by race and ethnicity. Sensitivity analyses included testing results across a range of inputs. The model was validated using the published RxPONDER trial data. RESULTS: In premenopausal women, the 10-year distant recurrence-free survival rates were 85.3% with chemo-endocrine and 80.1% with endocrine therapy. The estimated life-years and QALYs gained with chemotherapy in premenopausal women were 2.1 and 0.6, respectively. There was no chemotherapy benefit in postmenopausal women. There was no variation in the absolute benefit of chemotherapy across racial or ethnic subgroups. However, there were differences in distant recurrence-free survival rates, life-years, and QALYs across groups. Sensitivity analysis showed similar results. The model closely replicated the RxPONDER trial. CONCLUSIONS: Modeled population-level outcomes show a small chemotherapy benefit in premenopausal women, but no benefit among postmenopausal women. Simulation modeling provides a useful tool to extend trial data and evaluate population-level outcomes.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Neoplasias de la Mama/mortalidad , Persona de Mediana Edad , Adulto , Anciano , Simulación por Computador , Premenopausia , Posmenopausia , Años de Vida Ajustados por Calidad de Vida , Metástasis Linfática , Perfilación de la Expresión Génica/métodos , Recurrencia Local de Neoplasia/genética , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Supervivencia sin Enfermedad
15.
Exp Eye Res ; 238: 109729, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38052338

RESUMEN

PURPOSE: To characterize the neuronal and vascular pathology in vivo and in vitro in a mouse model of radiation retinopathy. METHODS: C57Bl/6J mice underwent cranial irradiation with 12 Gy and in vivo imaging by optical coherence tomography and of relative blood flow velocity by laser speckle flowgraphy for up to 3-6 months after irradiation. Retinal architecture, vascular density and leakage and apoptosis were analyzed by histology and immunohistochemistry before irradiation or at 10, 30, 240, and 365 days after treatment. RESULTS: The vascular density decreased in the plexiform layers starting at 30 days after irradiation. No impairment in retinal flow velocity was seen. Subtle perivascular leakage was present at 10 days, in particular in the outer plexiform layer. This corresponded to increased width of this layer. However, no significant change in the retinal thickness was detected by OCT-B scans. At 365 days after irradiation, the nuclear density was significantly reduced compared to baseline. Apoptosis was detected at 30 days and less prominent at 365 days. CONCLUSIONS: By histology, vascular leakage at 10 days was followed by increased neuronal apoptosis and loss of neuronal and vascular density. However, in vivo imaging approaches that are commonly used in human patients did not detect pathology in mice.


Asunto(s)
Traumatismos por Radiación , Enfermedades de la Retina , Humanos , Ratones , Animales , Angiografía con Fluoresceína , Retina , Vasos Retinianos/patología , Neuronas , Modelos Animales de Enfermedad , Traumatismos por Radiación/patología , Enfermedades de la Retina/etiología , Enfermedades de la Retina/patología , Tomografía de Coherencia Óptica/métodos
16.
Heredity (Edinb) ; 132(1): 5-17, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37952041

RESUMEN

The imprinted isoform of the Mest gene in mice is involved in key mammalian traits such as placental and fetal growth, maternal care and mammary gland maturation. The imprinted isoform has a distinct differentially methylated region (DMR) at its promoter in eutherian mammals but in marsupials, there are no differentially methylated CpG islands between the parental alleles. Here, we examined similarities and differences in the MEST gene locus across mammals using a marsupial, the tammar wallaby, a monotreme, the platypus, and a eutherian, the mouse, to investigate how imprinting of this gene evolved in mammals. By confirming the presence of the short isoform in all mammalian groups (which is imprinted in eutherians), this study suggests that an alternative promoter for the short isoform evolved at the MEST gene locus in the common ancestor of mammals. In the tammar, the short isoform of MEST shared the putative promoter CpG island with an antisense lncRNA previously identified in humans and an isoform of a neighbouring gene CEP41. The antisense lncRNA was expressed in tammar sperm, as seen in humans. This suggested that the conserved lncRNA might be important in the establishment of MEST imprinting in therian mammals, but it was not imprinted in the tammar. In contrast to previous studies, this study shows that MEST is not imprinted in marsupials. MEST imprinting in eutherians, therefore must have occurred after the marsupial-eutherian split with the acquisition of a key epigenetic imprinting control region, the differentially methylated CpG islands between the parental alleles.


Asunto(s)
Impresión Genómica , Macropodidae , Proteínas , ARN Largo no Codificante , Animales , Femenino , Humanos , Masculino , Ratones , Embarazo , Metilación de ADN , Euterios/genética , Euterios/metabolismo , Macropodidae/genética , Macropodidae/metabolismo , Placenta/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteínas/genética , Proteínas/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Semen/metabolismo
17.
Crit Rev Food Sci Nutr ; : 1-29, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39141568

RESUMEN

Dietary fiber-rich foods have been associated with numerous health benefits, including a reduced risk of cardiovascular and metabolic diseases. Harnessing the potential to deliver positive health outcomes rests on our understanding of the underlying mechanisms that drive these associations. This review addresses data and concepts concerning plant-based food functionality by dissecting the cascade of physical and chemical digestive processes and interactions that underpin these physiological benefits. Functional transformations of dietary fiber along the gastrointestinal tract from the stages of oral processing and gastric emptying to intestinal digestion and colonic fermentation influence its capacity to modulate digestion, transit, and commensal microbiome. This analysis highlights the significance, limitations, and challenges in decoding the complex web of interactions to establish a coherent framework connecting specific fiber components' molecular and macroscale interactions across multiple length scales within the gastrointestinal tract. One critical area that requires closer examination is the interaction between fiber, mucus barrier, and the commensal microbiome when considering food structure design and personalized nutritional strategies for beneficial physiologic effects. Understanding the response of specific fibers, particularly concerning an individual's physiology, will offer the opportunity to exploit these functional characteristics to elicit specific, symptom-targeting effects or use fiber types as adjunctive therapies.

18.
Int J Behav Nutr Phys Act ; 21(1): 100, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39256770

RESUMEN

BACKGROUND: Our systematic review aimed to critically evaluate empirical literature describing the association of muscle-strengthening exercise (MSE) with recurrence and/or mortality among breast cancer survivors. METHODS: We included English-language empirical research studies examining the association between MSE and recurrence and/or mortality among females diagnosed with breast cancer. Seven databases (MEDLINE, PsycINFO, Embase, Scopus, Web of Science, Cochrane CENTRAL, and CINAHL) were searched in September 2023. Quality was appraised using the Mixed Methods Appraisal Tool. Results are summarized descriptively. RESULTS: Five sources were identified. MSE measurement differed in relation to the description of the MSE (i.e., muscle-strengthening vs. strength training), examples of activities (e.g., sit-ups or push-ups vs. calisthenics vs. circuit training), and exercise frequency (i.e., days vs. times/week). Findings offer provisional evidence that some MSE may lower the hazards of recurrence and mortality. This association may vary by race, weight status, and menopausal status. CONCLUSIONS: In summary, limited available evidence suggests that MSE may lower the hazards of recurrence and mortality. More consistent measurement and analyses would help generate findings that are more readily comparable and applicable to inform clinical practice. Further research is needed to improve understanding of the strength and differences of these associations among underserved and underrepresented women.


Asunto(s)
Neoplasias de la Mama , Supervivientes de Cáncer , Fuerza Muscular , Recurrencia Local de Neoplasia , Entrenamiento de Fuerza , Femenino , Humanos , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/fisiopatología , Supervivientes de Cáncer/estadística & datos numéricos , Ejercicio Físico/fisiología , Fuerza Muscular/fisiología , Recurrencia Local de Neoplasia/epidemiología , Recurrencia Local de Neoplasia/fisiopatología , Recurrencia Local de Neoplasia/prevención & control
19.
Nucleic Acids Res ; 50(7): 3985-3997, 2022 04 22.
Artículo en Inglés | MEDLINE | ID: mdl-35357498

RESUMEN

Yersinia phage YerA41 is morphologically similar to jumbo bacteriophages. The isolated genomic material of YerA41 could not be digested by restriction enzymes, and used as a template by conventional DNA polymerases. Nucleoside analysis of the YerA41 genomic material, carried out to find out whether this was due to modified nucleotides, revealed the presence of a ca 1 kDa substitution of thymidine with apparent oligosaccharide character. We identified and purified the phage DNA polymerase (DNAP) that could replicate the YerA41 genomic DNA even without added primers. Cryo-electron microscopy (EM) was used to characterize structural details of the phage particle. The storage capacity of the 131 nm diameter head was calculated to accommodate a significantly longer genome than that of the 145 577 bp genomic DNA of YerA41 determined here. Indeed, cryo-EM revealed, in contrast to the 25 Å in other phages, spacings of 33-36 Å between shells of the genomic material inside YerA41 heads suggesting that the heavily substituted thymidine increases significantly the spacing of the DNA packaged inside the capsid. In conclusion, YerA41 appears to be an unconventional phage that packages thymidine-modified genomic DNA into its capsids along with its own DNAP that has the ability to replicate the genome.


Asunto(s)
Bacteriófagos , Bacteriófagos/química , Bacteriófagos/genética , Cápside , Microscopía por Crioelectrón , ADN Viral/genética , ADN Polimerasa Dirigida por ADN/genética , Genoma Viral/genética , Timidina
20.
Urol Int ; : 1-10, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39250884

RESUMEN

INTRODUCTION: Testicular cancer accounts for the largest proportion of solid tumors in young adult men. With an average age of onset under 40 years and a relative 5-year survival of 97%, it is one of the prognostically favorable tumors. Little is known about the relationship between the financial burden and physical and emotional health of testicular cancer survivors. We examined the association between financial problems caused by cancer and the self-reported quality of life in a cohort-based sample of testicular cancer patients. METHODS: A cross-sectional analysis of testicular cancer patients (n = 87, average age 39 years) was performed. Self-reported data were collected on demographics, income, wealth, cost-coping strategies, out-of-pocket costs, supportive medication compliance, quality of life and perceived social isolation. A multivariable regression model was used to examine the relationship between the degree to which cancer caused financial burdens and the patients´ reported quality of life. RESULTS: The survey showed that, in addition to illness-related additional expenses, a disease-related loss of income can lead to severe financial disadvantages and impair quality of life. The study data show that concerns about the economic situation can increase the burden on patients which already results from cancer diagnosis and therapy. In this patient cohort, 32% reported financial stress. CONCLUSION: Financial distress affects testicular cancer survivors in unique ways. To provide support, health professionals should consider survivors´ developmental life stage to understand their financial stress, and ultimately, to improve quality of life.

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