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1.
Cell ; 184(6): 1530-1544, 2021 03 18.
Artículo en Inglés | MEDLINE | ID: mdl-33675692

RESUMEN

The prevalence of type 2 diabetes and obesity has risen dramatically for decades and is expected to rise further, secondary to the growing aging, sedentary population. The strain on global health care is projected to be colossal. This review explores the latest work and emerging ideas related to genetic and environmental factors influencing metabolism. Translational research and clinical applications, including the impact of the COVID-19 pandemic, are highlighted. Looking forward, strategies to personalize all aspects of prevention, management and care are necessary to improve health outcomes and reduce the impact of these metabolic diseases.


Asunto(s)
COVID-19/epidemiología , Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/terapia , Obesidad/epidemiología , Obesidad/terapia , Pandemias , Medicina de Precisión/métodos , SARS-CoV-2 , COVID-19/virología , Ritmo Circadiano , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Epigénesis Genética , Predisposición Genética a la Enfermedad , Humanos , Inflamación/inmunología , Inflamación/metabolismo , Obesidad/genética , Obesidad/metabolismo , Prevalencia , Factores de Riesgo , Termotolerancia
2.
Cell ; 176(1-2): 1, 2019 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-30633900

RESUMEN

During the postpartum period, the brain's inhibitory GABAA receptors may not recover in time following their reduced numbers during pregnancy. This is likely the cause of postpartum depression prevalent in ∼12% of childbearing women. A new therapy for this condition consists of administering a synthetic neurosteroid during the postpartum period to alleviate the mood disorder. To view this Bench to Bedside, open or download the PDF.


Asunto(s)
Depresión Posparto/terapia , Pregnanolona/farmacología , Receptores de GABA-A/metabolismo , beta-Ciclodextrinas/farmacología , Adulto , Depresión Posparto/metabolismo , Trastorno Depresivo Mayor/metabolismo , Trastorno Depresivo Mayor/terapia , Combinación de Medicamentos , Femenino , Humanos , Trastornos del Humor , Neurotransmisores/farmacología , Periodo Posparto/metabolismo , Embarazo , Prevalencia , Receptores de GABA-A/fisiología
3.
Immunity ; 55(6): 1051-1066.e4, 2022 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-35649416

RESUMEN

Microbial exposures are crucial environmental factors that impact healthspan by sculpting the immune system and microbiota. Antibody profiling via Phage ImmunoPrecipitation Sequencing (PhIP-Seq) provides a high-throughput, cost-effective approach for detecting exposure and response to microbial protein products. We designed and constructed a library of 95,601 56-amino acid peptide tiles spanning 14,430 proteins with "toxin" or "virulence factor" keyword annotations. We used PhIP-Seq to profile the antibodies of ∼1,000 individuals against this "ToxScan" library. In addition to enumerating immunodominant antibody epitopes, we studied the age-dependent stability of the ToxScan profile and used a genome-wide association study to find that the MHC-II locus modulates bacterial epitope selection. We detected previously described anti-flagellin antibody responses in a Crohn's disease cohort and identified an association between anti-flagellin antibodies and juvenile dermatomyositis. PhIP-Seq with the ToxScan library is thus an effective tool for studying the environmental determinants of health and disease at cohort scale.


Asunto(s)
Bacteriófagos , Biblioteca de Péptidos , Secuencia de Aminoácidos , Anticuerpos , Formación de Anticuerpos , Bacteriófagos/genética , Estudio de Asociación del Genoma Completo , Humanos , Epítopos Inmunodominantes , Prevalencia , Factores de Virulencia/genética
4.
Immunity ; 54(10): 2172-2176, 2021 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-34626549

RESUMEN

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its associated disease, coronavirus disease 2019 (COVID-19), has caused a devastating pandemic worldwide. Here, we explain basic concepts underlying the transition from an epidemic to an endemic state, where a pathogen is stably maintained in a population. We discuss how the number of infections and the severity of disease change in the transition from the epidemic to the endemic phase and consider the implications of this transition in the context of COVID-19.


Asunto(s)
COVID-19/epidemiología , COVID-19/inmunología , Enfermedades Endémicas , COVID-19/prevención & control , Susceptibilidad a Enfermedades/epidemiología , Susceptibilidad a Enfermedades/inmunología , Epidemias , Humanos , Inmunidad , Prevalencia , SARS-CoV-2/inmunología , Índice de Severidad de la Enfermedad , Vacunación
5.
Nature ; 626(8001): 1094-1101, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38383783

RESUMEN

Persistent SARS-CoV-2 infections may act as viral reservoirs that could seed future outbreaks1-5, give rise to highly divergent lineages6-8 and contribute to cases with post-acute COVID-19 sequelae (long COVID)9,10. However, the population prevalence of persistent infections, their viral load kinetics and evolutionary dynamics over the course of infections remain largely unknown. Here, using viral sequence data collected as part of a national infection survey, we identified 381 individuals with SARS-CoV-2 RNA at high titre persisting for at least 30 days, of which 54 had viral RNA persisting at least 60 days. We refer to these as 'persistent infections' as available evidence suggests that they represent ongoing viral replication, although the persistence of non-replicating RNA cannot be ruled out in all. Individuals with persistent infection had more than 50% higher odds of self-reporting long COVID than individuals with non-persistent infection. We estimate that 0.1-0.5% of infections may become persistent with typically rebounding high viral loads and last for at least 60 days. In some individuals, we identified many viral amino acid substitutions, indicating periods of strong positive selection, whereas others had no consensus change in the sequences for prolonged periods, consistent with weak selection. Substitutions included mutations that are lineage defining for SARS-CoV-2 variants, at target sites for monoclonal antibodies and/or are commonly found in immunocompromised people11-14. This work has profound implications for understanding and characterizing SARS-CoV-2 infection, epidemiology and evolution.


Asunto(s)
COVID-19 , Encuestas Epidemiológicas , Infección Persistente , SARS-CoV-2 , Humanos , Sustitución de Aminoácidos , Anticuerpos Monoclonales/inmunología , COVID-19/epidemiología , COVID-19/virología , Evolución Molecular , Huésped Inmunocomprometido/inmunología , Mutación , Infección Persistente/epidemiología , Infección Persistente/virología , Síndrome Post Agudo de COVID-19/epidemiología , Síndrome Post Agudo de COVID-19/virología , Prevalencia , ARN Viral/análisis , ARN Viral/genética , SARS-CoV-2/química , SARS-CoV-2/clasificación , SARS-CoV-2/genética , SARS-CoV-2/inmunología , SARS-CoV-2/aislamiento & purificación , Selección Genética , Autoinforme , Factores de Tiempo , Carga Viral , Replicación Viral
6.
Annu Rev Genet ; 55: 265-283, 2021 11 23.
Artículo en Inglés | MEDLINE | ID: mdl-34579539

RESUMEN

Alleles that introgress between species can influence the evolutionary and ecological fate of species exposed to novel environments. Hybrid offspring of different species are often unfit, and yet it has long been argued that introgression can be a potent force in evolution, especially in plants. Over the last two decades, genomic data have increasingly provided evidence that introgression is a critically important source of genetic variation and that this additional variation can be useful in adaptive evolution of both animals and plants. Here, we review factors that influence the probability that foreign genetic variants provide long-term benefits (so-called adaptive introgression) and discuss their potential benefits. We find that introgression plays an important role in adaptive evolution, particularly when a species is far from its fitness optimum, such as when they expand their range or are subject to changing environments.


Asunto(s)
Evolución Biológica , Genoma , Animales , Genómica , Hibridación Genética , Plantas/genética , Prevalencia
7.
Immunity ; 53(5): 925-933.e4, 2020 11 17.
Artículo en Inglés | MEDLINE | ID: mdl-33129373

RESUMEN

We conducted a serological study to define correlates of immunity against SARS-CoV-2. Compared to those with mild coronavirus disease 2019 (COVID-19) cases, individuals with severe disease exhibited elevated virus-neutralizing titers and antibodies against the nucleocapsid (N) and the receptor binding domain (RBD) of the spike protein. Age and sex played lesser roles. All cases, including asymptomatic individuals, seroconverted by 2 weeks after PCR confirmation. Spike RBD and S2 and neutralizing antibodies remained detectable through 5-7 months after onset, whereas α-N titers diminished. Testing 5,882 members of the local community revealed only 1 sample with seroreactivity to both RBD and S2 that lacked neutralizing antibodies. This fidelity could not be achieved with either RBD or S2 alone. Thus, inclusion of multiple independent assays improved the accuracy of antibody tests in low-seroprevalence communities and revealed differences in antibody kinetics depending on the antigen. We conclude that neutralizing antibodies are stably produced for at least 5-7 months after SARS-CoV-2 infection.


Asunto(s)
Betacoronavirus/inmunología , Técnicas de Laboratorio Clínico/métodos , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/inmunología , Inmunidad Humoral , Neumonía Viral/epidemiología , Neumonía Viral/inmunología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Neutralizantes/sangre , Anticuerpos Antivirales/sangre , Arizona/epidemiología , Betacoronavirus/aislamiento & purificación , COVID-19 , Prueba de COVID-19 , Infecciones por Coronavirus/sangre , Infecciones por Coronavirus/diagnóstico , Proteínas de la Nucleocápside de Coronavirus , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proteínas de la Nucleocápside/inmunología , Pandemias , Fosfoproteínas , Neumonía Viral/sangre , Neumonía Viral/diagnóstico , Prevalencia , Dominios y Motivos de Interacción de Proteínas , SARS-CoV-2 , Estudios Seroepidemiológicos , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/inmunología , Adulto Joven
8.
CA Cancer J Clin ; 72(1): 57-77, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34714553

RESUMEN

Oral mucositis (OM) is a common, highly symptomatic complication of cancer therapy that affects patients' function, quality of life, and ability to tolerate treatment. In certain patients with cancer, OM is associated with increased mortality. Research on the management of OM is ongoing. Oral mucosal toxicities are also reported in targeted and immune checkpoint inhibitor therapies. The objective of this article is to present current knowledge about the epidemiology, pathogenesis, assessment, risk prediction, and current and developing intervention strategies for OM and other ulcerative mucosal toxicities caused by both conventional and evolving forms of cancer therapy.


Asunto(s)
Antineoplásicos/efectos adversos , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Neoplasias/terapia , Úlceras Bucales/epidemiología , Traumatismos por Radiación/epidemiología , Estomatitis/epidemiología , Humanos , Mucosa Bucal/efectos de los fármacos , Mucosa Bucal/patología , Mucosa Bucal/efectos de la radiación , Úlceras Bucales/diagnóstico , Úlceras Bucales/etiología , Úlceras Bucales/psicología , Prevalencia , Calidad de Vida , Traumatismos por Radiación/diagnóstico , Traumatismos por Radiación/etiología , Traumatismos por Radiación/psicología , Índice de Severidad de la Enfermedad , Estomatitis/diagnóstico , Estomatitis/etiología , Estomatitis/psicología
9.
Genes Dev ; 35(15-16): 1079-1092, 2021 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-34266888

RESUMEN

Chromosome gains and losses are a frequent feature of human cancers. However, how these aberrations can outweigh the detrimental effects of aneuploidy remains unclear. An initial comparison of existing chromosomal instability (CIN) mouse models suggests that aneuploidy accumulates to low levels in these animals. We therefore developed a novel mouse model that enables unprecedented levels of chromosome missegregation in the adult animal. At the earliest stages of T-cell development, cells with random chromosome gains and/or losses are selected against, but CIN eventually results in the expansion of progenitors with clonal chromosomal imbalances. Clonal selection leads to the development of T-cell lymphomas with stereotypic karyotypes in which chromosome 15, containing the Myc oncogene, is gained with high prevalence. Expressing human MYC from chromosome 6 (MYCChr6) is sufficient to change the karyotype of these lymphomas to include universal chromosome 6 gains. Interestingly, while chromosome 15 is still gained in MYCChr6 tumors after genetic ablation of the endogenous Myc locus, this chromosome is not efficiently gained after deletion of one copy of Rad21, suggesting a synergistic effect of both MYC and RAD21 in driving chromosome 15 gains. Our results show that the initial detrimental effects of random missegregation are outbalanced by clonal selection, which is dictated by the chromosomal location and nature of certain genes and is sufficient to drive cancer with high prevalence.


Asunto(s)
Aneuploidia , Inestabilidad Cromosómica , Animales , Transformación Celular Neoplásica/genética , Inestabilidad Cromosómica/genética , Aberraciones Cromosómicas , Cariotipo , Ratones , Prevalencia , Células Madre
10.
CA Cancer J Clin ; 71(3): 250-263, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33283888

RESUMEN

Sexual function is a vital aspect of quality of life among adolescent and young adult (AYA) (ages 15-39 years) cancer survivors. Sexual function encompasses physical, psychosocial, and developmental factors that contribute to sexual health, all of which may be negatively impacted by cancer and treatment. However, limited information is available to inform the care of AYA cancer survivors in this regard. This scoping review, conducted by the Children's Oncology Group AYA Oncology Discipline Committee, summarizes available literature regarding sexual function among AYA cancer survivors, including relevant psychosexual aspects of romantic relationships and body image. Results suggest that, overall, AYA cancer survivors experience a substantial burden of sexual dysfunction. Both physical and psychosocial sequelae influence survivors' sexual health. Interventions to support sexual health and psychosexual adjustment after cancer treatment are needed. Collaborations between the Children's Oncology Group and adult-focused cooperative groups within the National Cancer Institute's National Clinical Trials Network are warranted to advance prospective assessment of sexual dysfunction and test interventions to improve sexual health among AYA cancer survivors.


Asunto(s)
Supervivientes de Cáncer/psicología , Relaciones Interpersonales , Disfunciones Sexuales Fisiológicas/epidemiología , Disfunciones Sexuales Psicológicas/epidemiología , Salud Sexual , Adolescente , Adulto , Imagen Corporal/psicología , Humanos , Orgasmo , Prevalencia , Calidad de Vida , Excitación Sexual , Disfunciones Sexuales Fisiológicas/fisiopatología , Disfunciones Sexuales Fisiológicas/psicología , Disfunciones Sexuales Psicológicas/fisiopatología , Disfunciones Sexuales Psicológicas/psicología , Adulto Joven
11.
PLoS Biol ; 22(1): e3002457, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38175839

RESUMEN

Heteroresistance (HR) is an enigmatic phenotype where, in a main population of susceptible cells, small subpopulations of resistant cells exist. This is a cause for concern, as this small subpopulation is difficult to detect by standard antibiotic susceptibility tests, and upon antibiotic exposure the resistant subpopulation may increase in frequency and potentially lead to treatment complications or failure. Here, we determined the prevalence and mechanisms of HR for 40 clinical Staphylococcus aureus isolates, against 6 clinically important antibiotics: daptomycin, gentamicin, linezolid, oxacillin, teicoplanin, and vancomycin. High frequencies of HR were observed for gentamicin (69.2%), oxacillin (27%), daptomycin (25.6%), and teicoplanin (15.4%) while none of the isolates showed HR toward linezolid or vancomycin. Point mutations in various chromosomal core genes, including those involved in membrane and peptidoglycan/teichoic acid biosynthesis and transport, tRNA charging, menaquinone and chorismite biosynthesis and cyclic-di-AMP biosynthesis, were the mechanisms responsible for generating the resistant subpopulations. This finding is in contrast to gram-negative bacteria, where increased copy number of bona fide resistance genes via tandem gene amplification is the most prevalent mechanism. This difference can be explained by the observation that S. aureus has a low content of resistance genes and absence of the repeat sequences that allow tandem gene amplification of these genes as compared to gram-negative species.


Asunto(s)
Daptomicina , Infecciones Estafilocócicas , Humanos , Staphylococcus aureus/genética , Vancomicina , Linezolid/uso terapéutico , Teicoplanina/uso terapéutico , Prevalencia , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Infecciones Estafilocócicas/genética , Infecciones Estafilocócicas/tratamiento farmacológico , Oxacilina/uso terapéutico , Mutación , Gentamicinas
12.
PLoS Biol ; 22(3): e3002540, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38466718

RESUMEN

DNA methylation plays central roles in diverse cellular processes, ranging from error-correction during replication to regulation of bacterial defense mechanisms. Nevertheless, certain aberrant methylation modifications can have lethal consequences. The mechanisms by which bacteria detect and respond to such damage remain incompletely understood. Here, we discover a highly conserved but previously uncharacterized transcription factor (Cada2), which orchestrates a methylation-dependent adaptive response in Caulobacter. This response operates independently of the SOS response, governs the expression of genes crucial for direct repair, and is essential for surviving methylation-induced damage. Our molecular investigation of Cada2 reveals a cysteine methylation-dependent posttranslational modification (PTM) and mode of action distinct from its Escherichia coli counterpart, a trait conserved across all bacteria harboring a Cada2-like homolog instead. Extending across the bacterial kingdom, our findings support the notion of divergence and coevolution of adaptive response transcription factors and their corresponding sequence-specific DNA motifs. Despite this diversity, the ubiquitous prevalence of adaptive response regulators underscores the significance of a transcriptional switch, mediated by methylation PTM, in driving a specific and essential bacterial DNA damage response.


Asunto(s)
Bacterias , Metilación de ADN , Prevalencia , Bacterias/genética , Metilación de ADN/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Reparación del ADN , Procesamiento Proteico-Postraduccional , Daño del ADN/genética , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , ADN Bacteriano/metabolismo
13.
Nature ; 589(7841): 276-280, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33086375

RESUMEN

Suppressing infections of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) will probably require the rapid identification and isolation of individuals infected with the virus on an ongoing basis. Reverse-transcription polymerase chain reaction (RT-PCR) tests are accurate but costly, which makes the regular testing of every individual expensive. These costs are a challenge for all countries around the world, but particularly for low-to-middle-income countries. Cost reductions can be achieved by pooling (or combining) subsamples and testing them in groups1-7. A balance must be struck between increasing the group size and retaining test sensitivity, as sample dilution increases the likelihood of false-negative test results for individuals with a low viral load in the sampled region at the time of the test8. Similarly, minimizing the number of tests to reduce costs must be balanced against minimizing the time that testing takes, to reduce the spread of the infection. Here we propose an algorithm for pooling subsamples based on the geometry of a hypercube that, at low prevalence, accurately identifies individuals infected with SARS-CoV-2 in a small number of tests and few rounds of testing. We discuss the optimal group size and explain why, given the highly infectious nature of the disease, largely parallel searches are preferred. We report proof-of-concept experiments in which a positive subsample was detected even when diluted 100-fold with negative subsamples (compared with 30-48-fold dilutions described in previous studies9-11). We quantify the loss of sensitivity due to dilution and discuss how it may be mitigated by the frequent re-testing of groups, for example. With the use of these methods, the cost of mass testing could be reduced by a large factor. At low prevalence, the costs decrease in rough proportion to the prevalence. Field trials of our approach are under way in Rwanda and South Africa. The use of group testing on a massive scale to monitor infection rates closely and continually in a population, along with the rapid and effective isolation of people with SARS-CoV-2 infections, provides a promising pathway towards the long-term control of coronavirus disease 2019 (COVID-19).


Asunto(s)
Prueba de Ácido Nucleico para COVID-19/métodos , COVID-19/epidemiología , COVID-19/virología , Vigilancia de la Población/métodos , SARS-CoV-2/aislamiento & purificación , Algoritmos , COVID-19/diagnóstico , Humanos , Prevalencia , Rwanda/epidemiología , Sensibilidad y Especificidad
14.
Nature ; 599(7883): 108-113, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34551425

RESUMEN

Throughout the coronavirus disease 2019 (COVID-19) pandemic, countries have relied on a variety of ad hoc border control protocols to allow for non-essential travel while safeguarding public health, from quarantining all travellers to restricting entry from select nations on the basis of population-level epidemiological metrics such as cases, deaths or testing positivity rates1,2. Here we report the design and performance of a reinforcement learning system, nicknamed Eva. In the summer of 2020, Eva was deployed across all Greek borders to limit the influx of asymptomatic travellers infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and to inform border policies through real-time estimates of COVID-19 prevalence. In contrast to country-wide protocols, Eva allocated Greece's limited testing resources on the basis of incoming travellers' demographic information and testing results from previous travellers. By comparing Eva's performance against modelled counterfactual scenarios, we show that Eva identified 1.85 times as many asymptomatic, infected travellers as random surveillance testing, with up to 2-4 times as many during peak travel, and 1.25-1.45 times as many asymptomatic, infected travellers as testing policies that utilize only epidemiological metrics. We demonstrate that this latter benefit arises, at least partially, because population-level epidemiological metrics had limited predictive value for the actual prevalence of SARS-CoV-2 among asymptomatic travellers and exhibited strong country-specific idiosyncrasies in the summer of 2020. Our results raise serious concerns on the effectiveness of country-agnostic internationally proposed border control policies3 that are based on population-level epidemiological metrics. Instead, our work represents a successful example of the potential of reinforcement learning and real-time data for safeguarding public health.


Asunto(s)
COVID-19/diagnóstico , COVID-19/prevención & control , Portador Sano/diagnóstico , Portador Sano/prevención & control , Aprendizaje Automático , Medicina del Viajero , Viaje , COVID-19/epidemiología , COVID-19/transmisión , Portador Sano/epidemiología , Portador Sano/transmisión , Grecia , Humanos , Prevalencia , Salud Pública
15.
Nature ; 598(7880): 338-341, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34438440

RESUMEN

The COVID-19 pandemic disrupted health systems and economies throughout the world during 2020 and was particularly devastating for the United States, which experienced the highest numbers of reported cases and deaths during 20201-3. Many of the epidemiological features responsible for observed rates of morbidity and mortality have been reported4-8; however, the overall burden and characteristics of COVID-19 in the United States have not been comprehensively quantified. Here we use a data-driven model-inference approach to simulate the pandemic at county-scale in the United States during 2020 and estimate critical, time-varying epidemiological properties underpinning the dynamics of the virus. The pandemic in the United States during 2020 was characterized by national ascertainment rates that increased from 11.3% (95% credible interval (CI): 8.3-15.9%) in March to 24.5% (18.6-32.3%) during December. Population susceptibility at the end of the year was 69.0% (63.6-75.4%), indicating that about one third of the US population had been infected. Community infectious rates, the percentage of people harbouring a contagious infection, increased above 0.8% (0.6-1.0%) before the end of the year, and were as high as 2.4% in some major metropolitan areas. By contrast, the infection fatality rate fell to 0.3% by year's end.


Asunto(s)
COVID-19/epidemiología , COVID-19/transmisión , SARS-CoV-2 , Número Básico de Reproducción , COVID-19/economía , COVID-19/mortalidad , Calibración , Costo de Enfermedad , Humanos , Incidencia , Pandemias , Prevalencia , Estados Unidos/epidemiología
16.
Nature ; 597(7878): 703-708, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34428777

RESUMEN

SARS-CoV-2 infections have surged across the globe in recent months, concomitant with considerable viral evolution1-3. Extensive mutations in the spike protein may threaten the efficacy of vaccines and therapeutic monoclonal antibodies4. Two signature spike mutations of concern are E484K, which has a crucial role in the loss of neutralizing activity of antibodies, and N501Y, a driver of rapid worldwide transmission of the B.1.1.7 lineage. Here we report the emergence of the variant lineage B.1.526 (also known as the Iota variant5), which contains E484K, and its rise to dominance in New York City in early 2021. This variant is partially or completely resistant to two therapeutic monoclonal antibodies that are in clinical use and is less susceptible to neutralization by plasma from individuals who had recovered from SARS-CoV-2 infection or serum from vaccinated individuals, posing a modest antigenic challenge. The presence of the B.1.526 lineage has now been reported in all 50 states in the United States and in many other countries. B.1.526 rapidly replaced earlier lineages in New York, with an estimated transmission advantage of 35%. These transmission dynamics, together with the relative antibody resistance of its E484K sub-lineage, are likely to have contributed to the sharp rise and rapid spread of B.1.526. Although SARS-CoV-2 B.1.526 initially outpaced B.1.1.7 in the region, its growth subsequently slowed concurrently with the rise of B.1.1.7 and ensuing variants.


Asunto(s)
COVID-19/virología , SARS-CoV-2/crecimiento & desarrollo , SARS-CoV-2/aislamiento & purificación , Anticuerpos Neutralizantes/inmunología , Humanos , Mutación , New York/epidemiología , Filogenia , Filogeografía , Prevalencia , SARS-CoV-2/genética , SARS-CoV-2/inmunología , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/inmunología , Glicoproteína de la Espiga del Coronavirus/metabolismo , Estados Unidos/epidemiología
17.
N Engl J Med ; 389(13): 1191-1202, 2023 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-37754284

RESUMEN

BACKGROUND: Although the clinical efficacy of antimalarial artemisinin-based combination therapies in Africa remains high, the recent emergence of partial resistance to artemisinin in Plasmodium falciparum on the continent is troubling, given the lack of alternative treatments. METHODS: In this study, we used data from drug-efficacy studies conducted between 2016 and 2019 that evaluated 3-day courses of artemisinin-based combination therapy (artesunate-amodiaquine or artemether-lumefantrine) for uncomplicated malaria in Eritrea to estimate the percentage of patients with day-3 positivity (i.e., persistent P. falciparum parasitemia 3 days after the initiation of therapy). We also assayed parasites for mutations in Pfkelch13 as predictive markers of partial resistance to artemisinin and screened for deletions in hrp2 and hrp3 that result in variable performance of histidine rich protein 2 (HRP2)-based rapid diagnostic tests for malaria. RESULTS: We noted an increase in the percentage of patients with day-3 positivity from 0.4% (1 of 273) in 2016 to 1.9% (4 of 209) in 2017 and 4.2% (15 of 359) in 2019. An increase was also noted in the prevalence of the Pfkelch13 R622I mutation, which was detected in 109 of 818 isolates before treatment, from 8.6% (24 of 278) in 2016 to 21.0% (69 of 329) in 2019. The odds of day-3 positivity increased by a factor of 6.2 (95% confidence interval, 2.5 to 15.5) among the patients with Pfkelch13 622I variant parasites. Partial resistance to artemisinin, as defined by the World Health Organization, was observed in Eritrea. More than 5% of the patients younger than 15 years of age with day-3 positivity also had parasites that carried Pfkelch13 R622I. In vitro, the R622I mutation conferred a low level of resistance to artemisinin when edited into NF54 and Dd2 parasite lines. Deletions in both hrp2 and hrp3 were identified in 16.9% of the parasites that carried the Pfkelch13 R622I mutation, which made them potentially undetectable by HRP2-based rapid diagnostic tests. CONCLUSIONS: The emergence and spread of P. falciparum lineages with both Pfkelch13-mediated partial resistance to artemisinin and deletions in hrp2 and hrp3 in Eritrea threaten to compromise regional malaria control and elimination campaigns. (Funded by the Bill and Melinda Gates Foundation and others; Australian New Zealand Clinical Trials Registry numbers, ACTRN12618001223224, ACTRN12618000353291, and ACTRN12619000859189.).


Asunto(s)
Antimaláricos , Combinación Arteméter y Lumefantrina , Resistencia a Medicamentos , Malaria Falciparum , Plasmodium falciparum , Humanos , Amodiaquina/administración & dosificación , Amodiaquina/farmacología , Amodiaquina/uso terapéutico , Antimaláricos/farmacología , Antimaláricos/uso terapéutico , Combinación Arteméter y Lumefantrina/farmacología , Combinación Arteméter y Lumefantrina/uso terapéutico , Artemisininas/administración & dosificación , Artemisininas/farmacología , Artemisininas/uso terapéutico , Resistencia a Medicamentos/genética , Eritrea/epidemiología , Malaria Falciparum/tratamiento farmacológico , Malaria Falciparum/epidemiología , Malaria Falciparum/genética , Malaria Falciparum/parasitología , Plasmodium falciparum/efectos de los fármacos , Plasmodium falciparum/genética , Prevalencia
18.
PLoS Pathog ; 20(1): e1011908, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38198498

RESUMEN

Macroecological approaches can provide valuable insight into the epidemiology of globally distributed, multi-host pathogens. Toxoplasma gondii is a protozoan that infects any warm-blooded animal, including humans, in almost every habitat worldwide. Toxoplasma gondii infects its hosts through oocysts in the environment, carnivory of tissue cysts within intermediate host prey and vertical transmission. These routes of infection enable specific predictions regarding the ecological and life history traits that should predispose specific taxa to higher exposure and, thus infection rates of T. gondii. Using T. gondii prevalence data compiled from 485 studies representing 533 free-ranging wild mammalian species, we examined how ecological (habitat type, trophic level) and life history (longevity, vagility, gestation duration and torpor) traits influence T. gondii infection globally. We also compared T. gondii prevalence between wild and domesticated species from the same taxonomic families using data compiled from 540 studies of domestic cattle, sheep, and pigs. Across free-ranging wildlife, we found the average T. gondii prevalence was 22%, which is comparable to the global human estimate. Among ecological guilds, terrestrial species had lower T. gondii prevalence than aquatic species, with freshwater aquatic taxa having an increased prevalence compared to marine aquatic species. Dietary niches were also influential, with carnivores having an increased risk compared to other trophic feeding groups that have reduced tissue cyst exposure in their diet. With respect to influential life history traits, we found that more vagile wildlife species had higher T. gondii infection rates, perhaps because of the higher cumulative risk of infection during movement through areas with varying T. gondii environmental loads. Domestic farmed species had a higher T. gondii prevalence compared to free-ranging confamilial wildlife species. Through a macroecological approach, we determined the relative significance of transmission routes of a generalist pathogen, demonstrating an increased infection risk for aquatic and carnivorous species and highlighting the importance of preventing pathogen pollution into aquatic environments. Toxoplasma gondii is increasingly understood to be primarily an anthropogenically-associated pathogen whose dissemination is enhanced by ecosystem degradation and human subsidisation of free-roaming domestic cats. Adopting an ecosystem restoration approach to reduce one of the world's most common parasites would synergistically contribute to other initiatives in conservation, feline and wildlife welfare, climate change, food security and public health.


Asunto(s)
Toxoplasma , Toxoplasmosis Animal , Animales , Gatos , Bovinos , Animales Salvajes , Ecosistema , Mamíferos , Prevalencia , Ovinos , Porcinos , Toxoplasmosis Animal/epidemiología , Toxoplasmosis Animal/parasitología
19.
CA Cancer J Clin ; 69(3): 211-233, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30762872

RESUMEN

In the United States, African American/black individuals bear a disproportionate share of the cancer burden, having the highest death rate and the lowest survival rate of any racial or ethnic group for most cancers. To monitor progress in reducing these inequalities, every 3 years the American Cancer Society provides the estimated number of new cancer cases and deaths for blacks in the United States and the most recent data on cancer incidence, mortality, survival, screening, and risk factors using data from the National Cancer Institute, the North American Association of Central Cancer Registries, and the National Center for Health Statistics. In 2019, approximately 202,260 new cases of cancer and 73,030 cancer deaths are expected to occur among blacks in the United States. During 2006 through 2015, the overall cancer incidence rate decreased faster in black men than in white men (2.4% vs 1.7% per year), largely due to the more rapid decline in lung cancer. In contrast, the overall cancer incidence rate was stable in black women (compared with a slight increase in white women), reflecting increasing rates for cancers of the breast, uterine corpus, and pancreas juxtaposed with declining trends for cancers of the lung and colorectum. Overall cancer death rates declined faster in blacks than whites among both males (2.6% vs 1.6% per year) and females (1.5% vs 1.3% per year), largely driven by greater declines for cancers of the lung, colorectum, and prostate. Consequently, the excess risk of overall cancer death in blacks compared with whites dropped from 47% in 1990 to 19% in 2016 in men and from 19% in 1990 to 13% in 2016 in women. Moreover, the black-white cancer disparity has been nearly eliminated in men <50 years and women ≥70 years. Twenty-five years of continuous declines in the cancer death rate among black individuals translates to more than 462,000 fewer cancer deaths. Continued progress in reducing disparities will require expanding access to high-quality prevention, early detection, and treatment for all Americans.


Asunto(s)
Negro o Afroamericano/estadística & datos numéricos , Disparidades en el Estado de Salud , Disparidades en Atención de Salud/etnología , Neoplasias/etnología , Femenino , Humanos , Incidencia , Masculino , Neoplasias/mortalidad , Prevalencia , Factores de Riesgo , Programa de VERF , Estados Unidos/epidemiología
20.
CA Cancer J Clin ; 69(2): 88-112, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30548482

RESUMEN

The prevalence of excess body weight and the associated cancer burden have been rising over the past several decades globally. Between 1975 and 2016, the prevalence of excess body weight in adults-defined as a body mass index (BMI) ≥ 25 kg/m2 -increased from nearly 21% in men and 24% in women to approximately 40% in both sexes. Notably, the prevalence of obesity (BMI ≥ 30 kg/m2 ) quadrupled in men, from 3% to 12%, and more than doubled in women, from 7% to 16%. This change, combined with population growth, resulted in a more than 6-fold increase in the number of obese adults, from 100 to 671 million. The largest absolute increase in obesity occurred among men and boys in high-income Western countries and among women and girls in Central Asia, the Middle East, and North Africa. The simultaneous rise in excess body weight in almost all countries is thought to be driven largely by changes in the global food system, which promotes energy-dense, nutrient-poor foods, alongside reduced opportunities for physical activity. In 2012, excess body weight accounted for approximately 3.9% of all cancers (544,300 cases) with proportion varying from less than 1% in low-income countries to 7% or 8% in some high-income Western countries and in Middle Eastern and Northern African countries. The attributable burden by sex was higher for women (368,500 cases) than for men (175,800 cases). Given the pandemic proportion of excess body weight in high-income countries and the increasing prevalence in low- and middle-income countries, the global cancer burden attributable to this condition is likely to increase in the future. There is emerging consensus on opportunities for obesity control through the multisectoral coordinated implementation of core policy actions to promote an environment conducive to a healthy diet and active living. The rapid increase in both the prevalence of excess body weight and the associated cancer burden highlights the need for a rejuvenated focus on identifying, implementing, and evaluating interventions to prevent and control excess body weight.


Asunto(s)
Salud Global/estadística & datos numéricos , Neoplasias/etiología , Sobrepeso/epidemiología , Índice de Masa Corporal , Costo de Enfermedad , Femenino , Humanos , Masculino , Neoplasias/epidemiología , Obesidad/complicaciones , Obesidad/diagnóstico , Obesidad/epidemiología , Sobrepeso/complicaciones , Sobrepeso/diagnóstico , Prevalencia , Factores de Riesgo , Factores Sexuales
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