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1.
Cell ; 185(2): 266-282.e15, 2022 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-35026153

RESUMO

HIV-1-infected cells that persist despite antiretroviral therapy (ART) are frequently considered "transcriptionally silent," but active viral gene expression may occur in some cells, challenging the concept of viral latency. Applying an assay for profiling the transcriptional activity and the chromosomal locations of individual proviruses, we describe a global genomic and epigenetic map of transcriptionally active and silent proviral species and evaluate their longitudinal evolution in persons receiving suppressive ART. Using genome-wide epigenetic reference data, we show that proviral transcriptional activity is associated with activating epigenetic chromatin features in linear proximity of integration sites and in their inter- and intrachromosomal contact regions. Transcriptionally active proviruses were actively selected against during prolonged ART; however, this pattern was violated by large clones of virally infected cells that may outcompete negative selection forces through elevated intrinsic proliferative activity. Our results suggest that transcriptionally active proviruses are dynamically evolving under selection pressure by host factors.


Assuntos
HIV-1/genética , Provírus/genética , Transcrição Gênica , Idoso , Sequência de Bases , Evolução Biológica , Cromatina/metabolismo , Células Clonais , DNA Viral/genética , Epigênese Genética/efeitos dos fármacos , Feminino , Humanos , Ionomicina/farmacologia , Masculino , Pessoa de Meia-Idade , Filogenia , Provírus/efeitos dos fármacos , RNA Viral/genética , Acetato de Tetradecanoilforbol/farmacologia , Transcrição Gênica/efeitos dos fármacos , Integração Viral/genética , Latência Viral/efeitos dos fármacos , Latência Viral/genética
2.
Cell ; 170(2): 249-259.e25, 2017 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-28669536

RESUMO

Widespread resistance to first-line TB drugs is a major problem that will likely only be resolved through the development of new drugs with novel mechanisms of action. We have used structure-guided methods to develop a lead molecule that targets the thioesterase activity of polyketide synthase Pks13, an essential enzyme that forms mycolic acids, required for the cell wall of Mycobacterium tuberculosis. Our lead, TAM16, is a benzofuran class inhibitor of Pks13 with highly potent in vitro bactericidal activity against drug-susceptible and drug-resistant clinical isolates of M. tuberculosis. In multiple mouse models of TB infection, TAM16 showed in vivo efficacy equal to the first-line TB drug isoniazid, both as a monotherapy and in combination therapy with rifampicin. TAM16 has excellent pharmacological and safety profiles, and the frequency of resistance for TAM16 is ∼100-fold lower than INH, suggesting that it can be developed as a new antitubercular aimed at the acute infection. PAPERCLIP.


Assuntos
Antituberculosos/farmacologia , Benzofuranos/farmacologia , Desenho de Fármacos , Farmacorresistência Bacteriana , Mycobacterium tuberculosis/efeitos dos fármacos , Piperidinas/farmacologia , Tuberculose/microbiologia , Animais , Antituberculosos/química , Benzofuranos/química , Benzofuranos/farmacocinética , Linhagem Celular , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Modelos Moleculares , Piperidinas/química , Piperidinas/farmacocinética , Organismos Livres de Patógenos Específicos
3.
Nature ; 608(7922): 405-412, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35922506

RESUMO

After cessation of blood flow or similar ischaemic exposures, deleterious molecular cascades commence in mammalian cells, eventually leading to their death1,2. Yet with targeted interventions, these processes can be mitigated or reversed, even minutes or hours post mortem, as also reported in the isolated porcine brain using BrainEx technology3. To date, translating single-organ interventions to intact, whole-body applications remains hampered by circulatory and multisystem physiological challenges. Here we describe OrganEx, an adaptation of the BrainEx extracorporeal pulsatile-perfusion system and cytoprotective perfusate for porcine whole-body settings. After 1 h of warm ischaemia, OrganEx application preserved tissue integrity, decreased cell death and restored selected molecular and cellular processes across multiple vital organs. Commensurately, single-nucleus transcriptomic analysis revealed organ- and cell-type-specific gene expression patterns that are reflective of specific molecular and cellular repair processes. Our analysis comprises a comprehensive resource of cell-type-specific changes during defined ischaemic intervals and perfusion interventions spanning multiple organs, and it reveals an underappreciated potential for cellular recovery after prolonged whole-body warm ischaemia in a large mammal.


Assuntos
Sobrevivência Celular , Citoproteção , Perfusão , Suínos , Isquemia Quente , Animais , Morte Celular , Perfilação da Expressão Gênica , Isquemia/metabolismo , Isquemia/patologia , Isquemia/prevenção & controle , Especificidade de Órgãos , Perfusão/métodos , Suínos/anatomia & histologia
4.
Proc Natl Acad Sci U S A ; 121(12): e2316878121, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38466851

RESUMO

Deep sea cold seeps are sites where hydrogen sulfide, methane, and other hydrocarbon-rich fluids vent from the ocean floor. They are an important component of Earth's carbon cycle in which subsurface hydrocarbons form the energy source for highly diverse benthic micro- and macro-fauna in what is otherwise vast and spartan sea scape. Passive continental margin cold seeps are typically attributed to the migration of hydrocarbons generated from deeply buried source rocks. Many of these seeps occur over salt tectonic provinces, where the movement of salt generates complex fault systems that can enable fluid migration or create seals and traps associated with reservoir formation. The elevated advective heat transport of the salt also produces a chimney effect directly over these structures. Here, we provide geophysical and geochemical evidence that the salt chimney effect in conjunction with diapiric faulting drives a subsurface groundwater circulation system that brings dissolved inorganic carbon, nutrient-rich deep basinal fluids, and potentially overlying seawater onto the crests of deeply buried salt diapirs. The mobilized fluids fuel methanogenic archaea locally enhancing the deep biosphere. The resulting elevated biogenic methane production, alongside the upward heat-driven fluid transport, represents a previously unrecognized mechanism of cold seep formation and regulation.

5.
Am J Hum Genet ; 110(3): 427-441, 2023 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-36787739

RESUMO

Ewing sarcoma (EwS) is a rare bone and soft tissue malignancy driven by chromosomal translocations encoding chimeric transcription factors, such as EWSR1-FLI1, that bind GGAA motifs forming novel enhancers that alter nearby expression. We propose that germline microsatellite variation at the 6p25.1 EwS susceptibility locus could impact downstream gene expression and EwS biology. We performed targeted long-read sequencing of EwS blood DNA to characterize variation and genomic features important for EWSR1-FLI1 binding. We identified 50 microsatellite alleles at 6p25.1 and observed that EwS-affected individuals had longer alleles (>135 bp) with more GGAA repeats. The 6p25.1 GGAA microsatellite showed chromatin features of an EWSR1-FLI1 enhancer and regulated expression of RREB1, a transcription factor associated with RAS/MAPK signaling. RREB1 knockdown reduced proliferation and clonogenic potential and reduced expression of cell cycle and DNA replication genes. Our integrative analysis at 6p25.1 details increased binding of longer GGAA microsatellite alleles with acquired EWSR-FLI1 to promote Ewing sarcomagenesis by RREB1-mediated proliferation.


Assuntos
Neoplasias Ósseas , Sarcoma de Ewing , Humanos , Alelos , Neoplasias Ósseas/genética , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/metabolismo , Proteína Proto-Oncogênica c-fli-1/genética , Proteína Proto-Oncogênica c-fli-1/metabolismo , Proteína EWS de Ligação a RNA/genética , Proteína EWS de Ligação a RNA/metabolismo , Sarcoma de Ewing/genética , Sarcoma de Ewing/metabolismo , Sarcoma de Ewing/patologia
6.
Proc Natl Acad Sci U S A ; 120(10): e2216678120, 2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36857346

RESUMO

Low-light imaging is challenging in regimes where low-noise detectors are not yet available. One such regime is the shortwave infrared where even the best multipixel detector arrays typically have a noise floor in excess of 100 photons per pixel per frame. We present a homodyne imaging system capable of recovering both intensity and phase images of an object from a single frame despite an illumination intensity of ≈​1 photon per pixel. We interfere this weak signal which is below the noise floor of the detector with a reference beam that is ∼​300, 000 times brighter, record the resulting interference pattern in the spatial domain on a detector array, and use Fourier techniques to extract the intensity and phase images. We believe our approach could vastly extend the range of applications for low-light imaging by accessing domains where low-noise cameras are not currently available and for which low-intensity illumination is required.

7.
Proc Natl Acad Sci U S A ; 120(7): e2215371120, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-36749730

RESUMO

The ε4-allele variant of apolipoprotein E (ApoE4) is the strongest genetic risk factor for Alzheimer's disease, although it only differs from its neutral counterpart ApoE3 by a single amino acid substitution. While ApoE4 influences the formation of plaques and neurofibrillary tangles, the structural determinants of pathogenicity remain undetermined due to limited structural information. Previous studies have led to conflicting models of the C-terminal region positioning with respect to the N-terminal domain across isoforms largely because the data are potentially confounded by the presence of heterogeneous oligomers. Here, we apply a combination of single-molecule spectroscopy and molecular dynamics simulations to construct an atomically detailed model of monomeric ApoE4 and probe the effect of lipid association. Importantly, our approach overcomes previous limitations by allowing us to work at picomolar concentrations where only the monomer is present. Our data reveal that ApoE4 is far more disordered and extended than previously thought and retains significant conformational heterogeneity after binding lipids. Comparing the proximity of the N- and C-terminal domains across the three major isoforms (ApoE4, ApoE3, and ApoE2) suggests that all maintain heterogeneous conformations in their monomeric form, with ApoE2 adopting a slightly more compact ensemble. Overall, these data provide a foundation for understanding how ApoE4 differs from nonpathogenic and protective variants of the protein.


Assuntos
Apolipoproteína E4 , Apolipoproteínas E , Apolipoproteína E4/genética , Apolipoproteína E3/química , Apolipoproteína E2 , Conformação Proteica , Isoformas de Proteínas/metabolismo
8.
Trends Genet ; 38(5): 483-500, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35227512

RESUMO

Programmed elimination of DNA during development yields somatic cell nuclei with dramatically different DNA sequence and content relative to germline nuclei, profoundly influencing genome architecture and stability. Whole-genome sequencing has significantly expanded the list of taxa known to exhibit this trait and has revealed the identity of excised genes and transposable elements (TEs) in certain taxa. Here, we compare the diverse mechanisms employed by ciliates, nematodes, copepods, and lamprey to downsize their genomes during development and propose tests of hypotheses about the evolution and/or maintenance of this trait. We explore possible functional roles that programmed DNA elimination (PDE) could play in genomic defense (especially against TEs), regulation of development, sex determination, co-option, and modulating nucleotypic effects, which together argue for a place in the mainstream investigation of genome evolution.


Assuntos
Elementos de DNA Transponíveis , Genômica , Sequência de Bases , Núcleo Celular/genética , Elementos de DNA Transponíveis/genética , Evolução Molecular , Células Germinativas
9.
Blood ; 141(1): 90-101, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-36037430

RESUMO

Five-year survival following childhood acute myeloid leukemia (AML) has increased following improvements in treatment and supportive care. Long-term health outcomes are unknown. To address this, cumulative incidence of late mortality and grades 3 to 5 chronic health condition (CHC) were estimated among 5-year AML survivors diagnosed between 1970 and 1999. Survivors were compared by treatment group (hematopoietic cell transplantation [HCT], chemotherapy with cranial radiation [chemo + CRT], chemotherapy only [chemo-only]), and diagnosis decade. Self-reported health status was compared across treatments, diagnosis decade, and with siblings. Among 856 survivors (median diagnosis age, 7.1 years; median age at last follow-up, 29.4 years), 20-year late mortality cumulative incidence was highest after HCT (13.9%; 95% confidence interval [CI], 10.0%-17.8%; chemo + CRT, 7.6%; 95% CI, 2.2%-13.1%; chemo-only, 5.1%; 95% CI, 2.8%-7.4%). Cumulative incidence of mortality for HCT survivors diagnosed in the 1990s (8.5%; 95% CI, 4.1%-12.8%) was lower vs those diagnosed in the 1970s (38.9%; 95% CI, 16.4%-61.4%). Most survivors did not experience any grade 3 to 5 CHC after 20 years (HCT, 45.8%; chemo + CRT, 23.7%; chemo-only, 27.0%). Furthermore, a temporal reduction in CHC cumulative incidence was seen after HCT (1970s, 76.1%; 1990s, 38.3%; P = .02), mirroring reduced use of total body irradiation. Self-reported health status was good to excellent for 88.2% of survivors; however, this was lower than that for siblings (94.8%; P < .0001). Although HCT is associated with greater long-term morbidity and mortality than chemotherapy-based treatment, gaps have narrowed, and all treatment groups report favorable health status.


Assuntos
Sobreviventes de Câncer , Leucemia Mieloide Aguda , Transtornos Mieloproliferativos , Humanos , Criança , Adulto , Avaliação de Resultados em Cuidados de Saúde , Nível de Saúde , Leucemia Mieloide Aguda/terapia , Doença Crônica
10.
CA Cancer J Clin ; 68(2): 133-152, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29377070

RESUMO

The population of adult survivors of childhood cancer continues to grow as survival rates improve. Although it is well established that these survivors experience various complications and comorbidities related to their malignancy and treatment, this risk is modified by many factors that are not directly linked to their cancer history. Research evaluating the influence of patient-specific demographic and genetic factors, premorbid and comorbid conditions, health behaviors, and aging has identified additional risk factors that influence cancer treatment-related toxicity and possible targets for intervention in this population. Furthermore, although current long-term follow-up guidelines comprehensively address specific therapy-related risks and provide screening recommendations, the risk profile of the population continues to evolve with ongoing modification of treatment strategies and the emergence of novel therapeutics. To address the multifactorial modifiers of cancer treatment-related health risk and evolving treatment approaches, a patient-centered and risk-adapted approach to care that often requires a multidisciplinary team approach, including medical and behavioral providers, is necessary for this population. CA Cancer J Clin 2018;68:133-152. © 2018 American Cancer Society.


Assuntos
Sobreviventes de Câncer , Neoplasias/complicações , Neoplasias/psicologia , Assistência Centrada no Paciente , Adulto , Fatores Etários , Criança , Comportamentos Relacionados com a Saúde , Acessibilidade aos Serviços de Saúde , Humanos , Neoplasias/terapia , Qualidade de Vida , Fatores de Risco
11.
Genes Chromosomes Cancer ; 63(1): e23195, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37548271

RESUMO

Rhabdoid Tumor Predisposition Syndrome 1 (RTPS1) confers an increased risk of developing rhabdoid tumors and is caused by germline mutations in SMARCB1. RTPS1 should be evaluated in all individuals with rhabdoid tumor and is more likely in those with a young age at presentation (occasionally congenital presentation), multiple primary tumors, or a family history of rhabdoid tumor or RTPS1. Proband genetic testing is the standard method for diagnosing RTPS1. Most known RTPS1-related SMARCB1 gene mutations are copy number variants (CNVs) or single nucleotide variants/indels, but structural variant analysis (SVA) is not usually included in the molecular evaluation. Here, we report two children with RTPS1 presenting with atypical teratoid/rhabdoid tumor (ATRT) who had constitutional testing showing balanced chromosome translocations involving SMARCB1. Patient 1 is a 23-year-old female diagnosed with pineal region ATRT at 7 months who was found to have a de novo, constitutional t(16;22)(p13.3;q11.2). Patient 2 is a 24-month-old male diagnosed with a posterior fossa ATRT at 14 months, with subsequent testing showing a constitutional t(5;22)(q14.1;q11.23). These structural rearrangements have not been previously reported in RTPS1. While rare, these cases suggest that structural variants should be considered in the evaluation of children with rhabdoid tumors to provide more accurate genetic counseling on the risks of developing tumors, the need for surveillance, and the risks of passing the disorder on to future children. Further research is needed to understand the prevalence, clinical features, and tumor risks associated with RTPS1-related constitutional balanced translocations.


Assuntos
Neoplasias Encefálicas , Transtornos Cromossômicos , Tumor Rabdoide , Teratoma , Criança , Feminino , Masculino , Humanos , Adulto Jovem , Adulto , Lactente , Tumor Rabdoide/genética , Tumor Rabdoide/patologia , Proteína SMARCB1/genética , Neoplasias Encefálicas/genética , Mutação em Linhagem Germinativa , Translocação Genética , Teratoma/genética , Teratoma/patologia
12.
Lancet Oncol ; 25(6): 811-822, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38821086

RESUMO

BACKGROUND: The effect of the increasing lifetime burden of non-major cardiovascular conditions on risk for a subsequent major adverse cardiovascular event among survivors of childhood cancer has not been assessed. We aimed to characterise the prevalence of major adverse cardiovascular events and their association with the cumulative burden of non-major adverse cardiovascular events in childhood cancer survivors. METHODS: This is a longitudinal cohort study with participant data obtained from an ongoing cohort study at St Jude Children's Research Hospital: the St Jude Lifetime Cohort Study (SJLIFE). Prospective clinical follow-up was of 5-year survivors of childhood cancer who were diagnosed when aged younger than 25 years from 1962 to 2012. Age-frequency, sex-frequency, and race-frequency matched community-control participants completed a similar one-time clinical assessment. 22 cardiovascular events were graded using a St Jude Children's Research Hospital-modified version of the National Cancer Institute Common Terminology Criteria for Adverse Events (version 4.03). Cumulative incidence and burden of the primary outcome of major adverse cardiovascular events (cardiomyopathy, myocardial infarction, stroke, and other cardiovascular-related mortality) were estimated. Rate ratios (RR) of the association of major adverse cardiovascular events with 22 non-major adverse cardiovascular events were estimated using multivariable piecewise-exponential regression adjusting for attained age, age at diagnosis, sex, race and ethnicity, treatment era, diagnosis of diabetes, and exposure to cardiotoxic cancer therapies. The St Jude Lifetime Cohort study is registered with ClinicalTrials.gov, NCT00760656, and is ongoing. FINDINGS: 9602 5-year survivors of childhood cancer, and 737 community controls were included in the longitudinal follow-up (from Sept 13, 2007, to Dec 17, 2021). The median follow-up was 20·3 years (IQR 12·0-31·4) from the date of primary cancer diagnosis (4311 [44.9%] were females). By the age of 50 years (analysis stopped at age 50 years due to the low number of participants older than that age), the cumulative incidence of major adverse cardiovascular events among survivors was 17·7% (95% CI 15·9-19·5) compared with 0·9% (0·0-2·1) in the community controls. The cumulative burden of major adverse cardiovascular events in survivors was 0·26 (95% CI 0·23-0·29) events per survivor compared with 0·009 (0·000-0·021) events per community control participant. Increasing cumulative burden of grade 1-4 non-major adverse cardiovascular events was associated with an increased future risk of major adverse cardiovascular events (one condition: RR 4·3, 95% CI 3·1-6·0; p<0·0001; two conditions: 6·6, 4·6-9·5; p<0·0001; and three conditions: 7·7, 5·1-11·4; p<0·0001). Increased risk for major adverse cardiovascular events was observed with specific subclinical conditions (eg, grade 1 arrhythmias [RR 1·5, 95% CI 1·2-2·0; p=0·0017]), grade 2 left ventricular systolic dysfunction (2·2, 1·6-3·1; p<0·0001), grade 2 valvular disorders (2·2, 1·2-4·0; p=0·013), but not grade 1 hypercholesterolaemia, grade 1-2 hypertriglyceridaemia, or grade 1-2 vascular stenosis. INTERPRETATION: Among an ageing cohort of survivors of childhood cancer, the accumulation of non-major adverse cardiovascular events, including subclinical conditions, increased the risk of major adverse cardiovascular events and should be the focus of interventions for early detection and prevention of major adverse cardiovascular events. FUNDING: The US National Cancer Institute and the American Lebanese Syrian Associated Charities.


Assuntos
Sobreviventes de Câncer , Doenças Cardiovasculares , Neoplasias , Humanos , Masculino , Feminino , Doenças Cardiovasculares/epidemiologia , Estudos Prospectivos , Criança , Sobreviventes de Câncer/estatística & dados numéricos , Estudos Longitudinais , Adolescente , Neoplasias/epidemiologia , Adulto , Adulto Jovem , Pré-Escolar , Incidência , Fatores de Risco , Lactente , Prevalência , Medição de Risco
13.
J Neurosci ; 43(25): 4598-4611, 2023 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-37221096

RESUMO

Neurons exhibit a striking degree of functional diversity, each one tuned to the needs of the circuitry in which it is embedded. A fundamental functional dichotomy occurs in activity patterns, with some neurons firing at a relatively constant "tonic" rate, while others fire in bursts, a "phasic" pattern. Synapses formed by tonic versus phasic neurons are also functionally differentiated, yet the bases of their distinctive properties remain enigmatic. A major challenge toward illuminating the synaptic differences between tonic and phasic neurons is the difficulty in isolating their physiological properties. At the Drosophila neuromuscular junction, most muscle fibers are coinnervated by two motor neurons: the tonic "MN-Ib" and phasic "MN-Is." Here, we used selective expression of a newly developed botulinum neurotoxin transgene to silence tonic or phasic motor neurons in Drosophila larvae of either sex. This approach highlighted major differences in their neurotransmitter release properties, including probability, short-term plasticity, and vesicle pools. Furthermore, Ca2+ imaging demonstrated ∼2-fold greater Ca2+ influx at phasic neuron release sites relative to tonic, along with an enhanced synaptic vesicle coupling. Finally, confocal and super-resolution imaging revealed that phasic neuron release sites are organized in a more compact arrangement, with enhanced stoichiometry of voltage-gated Ca2+ channels relative to other active zone scaffolds. These data suggest that distinctions in active zone nano-architecture and Ca2+ influx collaborate to differentially tune glutamate release at tonic versus phasic synaptic subtypes.SIGNIFICANCE STATEMENT "Tonic" and "phasic" neuronal subtypes, based on differential firing properties, are common across many nervous systems. Using a recently developed approach to selectively silence transmission from one of these two neurons, we reveal specialized synaptic functional and structural properties that distinguish these specialized neurons. This study provides important insights into how input-specific synaptic diversity is achieved, which could have implications for neurologic disorders that involve changes in synaptic function.


Assuntos
Junção Neuromuscular , Sinapses , Animais , Sinapses/fisiologia , Junção Neuromuscular/metabolismo , Vesículas Sinápticas/metabolismo , Neurônios Motores/fisiologia , Drosophila
14.
J Am Chem Soc ; 146(11): 7708-7722, 2024 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-38457782

RESUMO

Developing new antibiotics and delivery strategies is of critical importance for treating infections caused by Gram-negative bacterial pathogens. Hijacking bacterial iron uptake machinery, such as that of the siderophore enterobactin (Ent), represents one promising approach toward these goals. Here, we report a novel Ent-inspired siderophore-antibiotic conjugate (SAC) employing an alternative siderophore moiety as the delivery vector and demonstrate the potency of our SACs harboring the ß-lactam antibiotic ampicillin (Amp) against multiple pathogenic Gram-negative bacterial strains. We establish the ability of N,N',N''-(nitrilotris(ethane-2,1-diyl))tris(2,3-dihydroxybenzamide) (TRENCAM, hereafter TC), a synthetic mimic of Ent, to facilitate drug delivery across the outer membrane (OM) of Gram-negative pathogens. Conjugation of Amp to a new monofunctionalized TC scaffold affords TC-Amp, which displays markedly enhanced antibacterial activity against the gastrointestinal pathogen Salmonella enterica serovar Typhimurium (STm) compared with unmodified Amp. Bacterial uptake, antibiotic susceptibility, and microscopy studies with STm show that the TC moiety facilitates TC-Amp uptake by the OM receptors FepA and IroN and that the Amp warhead inhibits penicillin-binding proteins. Moreover, TC-Amp achieves targeted activity, selectively killing STm in the presence of a commensal lactobacillus. Remarkably, we uncover that TC-Amp and its Ent-based predecessor Ent-Amp achieve enhanced antibacterial activity against diverse Gram-negative ESKAPE pathogens that express Ent uptake machinery, including strains that possess intrinsic ß-lactam resistance. TC-Amp and Ent-Amp exhibit potency comparable to that of the FDA-approved SAC cefiderocol against Gram-negative pathogens. These results demonstrate the effective application of native and appropriately designed nonnative siderophores as vectors for drug delivery across the OM of multiple Gram-negative bacterial pathogens.


Assuntos
Sideróforos , beta-Lactamas , Sideróforos/farmacologia , beta-Lactamas/farmacologia , Lactamas , Antibacterianos/farmacologia , Enterobactina/farmacologia , Enterobactina/metabolismo , Bactérias Gram-Negativas , Ferro
15.
Cancer ; 130(1): 128-139, 2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-37732943

RESUMO

BACKGROUND: Treatment exposures for childhood cancer reduce ovarian reserve. However, the success of assisted reproductive technology (ART) among female survivors is not well established. METHODS: Five-year survivors of childhood cancer in the Childhood Cancer Survivor Study were linked to the Society for Assisted Reproductive Technology Clinic Outcome Reporting System, which captures national ART outcomes. The authors assessed the live birth rate, the relative risk (RR) with 95% confidence intervals (95% CIs), and associations with treatment exposure using generalized estimating equations to account for multiple ovarian stimulations per individual. Siblings from a random sample of survivors were recruited to serve as a comparison group. RESULTS: Among 9885 female survivors, 137 (1.4%; median age at diagnosis, 10 years [range, 0-20 years]; median years of follow-up after age 18 years, 11 years [range, 2-11 years]) underwent 224 ovarian stimulations using autologous or donor eggs and/or gestational carriers (157 autologous ovarian stimulation cycles, 67 donor ovarian stimulation cycles). In siblings, 33 (1.4%) underwent 51 autologous or donor ovarian stimulations. Of those who used embryos from autologous eggs without using gestational carriers, 97 survivors underwent 155 stimulations, resulting in 49 live births, for a 31.6% chance of live birth per ovarian stimulation (vs. 38.3% for siblings; p = .39) and a 43.9% chance of live birth per transfer (vs. 50.0%; p = .33). Prior treatment with cranial radiation therapy (RR, 0.44; 95% CI, 0.20-0.97) and pelvic radiation therapy (RR, 0.33; 95% CI, 0.15-0.73) resulted in a reduced chance of live birth compared with siblings. The likelihood of live birth after ART treatment in survivors was not affected by alkylator exposure (cyclophosphamide-equivalent dose, ≥8000 mg/m2 vs. none; RR, 1.04; 95% CI, 0.52-2.05). CONCLUSIONS: Childhood cancer survivors are as likely to undergo treatment using ART as sibling controls. The success of ART treatment was not reduced after alkylator exposure. The results from the current study provide needed guidance on the use of ART in this population.


Assuntos
Sobreviventes de Câncer , Neoplasias , Gravidez , Criança , Feminino , Humanos , Recém-Nascido , Lactente , Pré-Escolar , Adolescente , Adulto Jovem , Adulto , Neoplasias/terapia , Técnicas de Reprodução Assistida , Gravidez Múltipla , Alquilantes
16.
Cancer ; 130(12): 2224-2236, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38373075

RESUMO

BACKGROUND: Prevalence and risk of poor psychological outcomes following rhabdomyosarcoma (RMS) are not well-established. METHODS: Participants in this cross-sectional, case-control study (n = 713 survivors, 42.5% female; mean [SD] age, 30.5 [6.6] years; n = 706 siblings, 57.2% female; mean age, 32.8,[7.9] years) completed measures of neurocognition, emotional distress, and health-related quality of life (HRQOL). Multivariable logistic regression models identified treatments, health behaviors, and chronic conditions associated with impairment. RESULTS: Relative to siblings, more survivors reported neurocognitive impairment (task efficiency: 21.1% vs. 13.7%, emotional regulation: 16.7% vs. 11.0%, memory: 19.3% vs. 15.1%), elevated emotional distress (somatic distress: 12.9% vs. 4.7%, anxiety: 11.7% vs. 5.9%, depression: 22.8% vs. 16.9%) and poorer HRQOL (physical functioning: 11.1% vs. 2.8%, role functioning due to physical problems: 16.8% vs. 8.2%, pain: 17.5% vs. 10.0%, vitality: 22.3% vs. 13.8%, social functioning: 14.4% vs. 6.8%, emotional functioning: 17.1% vs. 10.6%). Cranial radiation increased risk for impaired task efficiency (odds ratio [OR], 2.30; 95% confidence interval [CI], 1.14-4.63), whereas chest and pelvic radiation predicted increased risk of physical functioning (OR, 2.68; 95% CI, 1.16-6.21 and OR, 3.44; 95% CI, 1.70-6.95, respectively). Smoking was associated with impaired task efficiency (OR, 2.06; 95% CI, 1.14-3.70), memory (OR, 2.23; 95% CI, 1.26-3.95), anxiety (OR, 2.71; 95% CI, 1.36-5.41) and depression (OR, 1.77; 95% CI, 1.01-3.11). Neurologic conditions increased risk of anxiety (OR, 2.30; 95% CI, 1.04-5.10), and hearing conditions increased risk of depression (OR, 1.79; 95% CI, 1.05-3.03). Neurologic and hearing conditions, respectively, were associated with impaired memory (OR, 2.44; 95% CI, 1.20-4.95 and OR, 1.87; 95% CI, 1.05-3.35) and poor health perception (OR, 2.62; 95% CI, 1.62-1.28 and OR, 2.33; 95% CI, 1.34-4.06). CONCLUSIONS: RMS survivors are at significant risk for poor psychological outcomes. Advancing therapies for local control, smoking cessation, and managing chronic medical conditions may mitigate poor outcomes following RMS.


Assuntos
Sobreviventes de Câncer , Angústia Psicológica , Qualidade de Vida , Rabdomiossarcoma , Humanos , Feminino , Masculino , Sobreviventes de Câncer/psicologia , Estudos de Casos e Controles , Adulto , Fatores de Risco , Rabdomiossarcoma/psicologia , Estudos Transversais , Criança , Adulto Jovem , Adolescente , Ansiedade/psicologia , Ansiedade/epidemiologia , Ansiedade/etiologia
17.
Cancer ; 130(7): 1125-1136, 2024 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-38100563

RESUMO

BACKGROUND: Siblings of children with cancer may experience adverse household economic consequences, but their financial outcomes in adulthood are unknown. METHODS: A total of 880 siblings (aged 18-64 years) of adult-aged childhood cancer survivors were surveyed to estimate the prevalence of financial hardship by three established domains (behavioral, material, and psychological). For individual financial hardship items matching the contemporaneous National Health Interview Survey or Behavioral Risk Factor Surveillance System, siblings were compared with the general population by calculating adjusted prevalence odds ratios (ORs) to sample-weighted responses. Multivariable logistic regression models examined associations between sibling characteristics and each hardship domain and between sibling hardship and survivors' cancer/treatment characteristics. RESULTS: Behavioral, material, and psychological hardship was reported by 24%, 35%, and 28%, respectively. Compared with national survey respondents, siblings were more likely to report worries about medical bills (OR, 1.14; 95% confidence interval [CI], 1.06-1.22), difficulty affording nutritious foods (OR, 1.79; 95% CI, 1.54-2.07), and forgoing needed medical care (OR, 1.38; 95% CI, 1.10-1.73), prescription medications (OR, 2.52; 95% CI, 1.99-3.20), and dental care (OR, 1.34; 95% CI, 1.15-1.57) because of cost. Sibling characteristics associated with reporting financial hardship in one or more domains included female sex, older age, chronic health conditions, lower income, not having health insurance, high out-of-pocket medical expenditures, and nonmedical/nonhome debt. No survivor cancer/treatment characteristics were associated with sibling financial hardship. CONCLUSIONS: Adult siblings of childhood cancer survivors were more likely to experience financial hardship compared with the general population. Childhood cancer may adversely affect entire households, with potentially lasting implications.


Assuntos
Sobreviventes de Câncer , Neoplasias , Adulto , Humanos , Criança , Feminino , Irmãos , Neoplasias/epidemiologia , Neoplasias/terapia , Estresse Financeiro/epidemiologia , Efeitos Psicossociais da Doença , Sobreviventes , Inquéritos e Questionários
18.
Lancet ; 401(10386): 1447-1457, 2023 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-37030315

RESUMO

BACKGROUND: 5-year survival after childhood cancer does not fully describe life-years lost due to childhood cancer because there are a large number of deaths occurring beyond 5-years (late mortality) related to cancer and cancer treatment. Specific causes of health-related (non-recurrence, non-external) late mortality and risk reduction through modifiable lifestyle and cardiovascular risk factors are not well described. Through using a well-characterised cohort of 5-year survivors of the most common childhood cancers, we evaluated specific health-related causes of late mortality and excess deaths compared with the general US population and identified targets to reduce future risk. METHODS: In this multi-institutional, hospital-based, retrospective cohort study, late mortality (death ≥5 years from diagnosis) and specific causes of death were evaluated in 34 230 5-year survivors of childhood cancer diagnosed at an age younger than 21 years from 1970 to 1999 at 31 institutions in the USA and Canada; median follow-up from diagnosis was 29 years (range 5-48) in the Childhood Cancer Survivor Study. Demographic, self-reported modifiable lifestyle (ie, smoking, alcohol, physical activity, and BMI) and cardiovascular risk factors (ie, hypertension, diabetes, and dyslipidaemia) associated with health-related mortality (which excludes death from primary cancer and external causes and includes death from late effects of cancer therapy) were evaluated. FINDINGS: 40-year cumulative all-cause mortality was 23·3% (95% CI 22·7-24·0), with 3061 (51·2%) of 5916 deaths from health-related causes. Survivors 40 years or more from diagnosis experienced 131 excess health-related deaths per 10 000 person-years (95% CI 111-163), including those due to the top three causes of health-related death in the general population: cancer (absolute excess risk per 10 000 person-years 54, 95% CI 41-68), heart disease (27, 18-38), and cerebrovascular disease (10, 5-17). Healthy lifestyle and absence of hypertension and diabetes were each associated with a 20-30% reduction in health-related mortality independent of other factors (all p values ≤0·002). INTERPRETATION: Survivors of childhood cancer are at excess risk of late mortality even 40 years from diagnosis, due to many of the leading causes of death in the US population. Modifiable lifestyle and cardiovascular risk factors associated with reduced risk for late mortality should be part of future interventions. FUNDING: US National Cancer Institute and the American Lebanese Syrian Associated Charities.


Assuntos
Sobreviventes de Câncer , Hipertensão , Neoplasias , Humanos , Criança , Adulto Jovem , Adulto , Estudos Retrospectivos , Fatores de Risco , Sobreviventes
19.
Nat Methods ; 18(2): 170-175, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33526886

RESUMO

Haplotype-resolved de novo assembly is the ultimate solution to the study of sequence variations in a genome. However, existing algorithms either collapse heterozygous alleles into one consensus copy or fail to cleanly separate the haplotypes to produce high-quality phased assemblies. Here we describe hifiasm, a de novo assembler that takes advantage of long high-fidelity sequence reads to faithfully represent the haplotype information in a phased assembly graph. Unlike other graph-based assemblers that only aim to maintain the contiguity of one haplotype, hifiasm strives to preserve the contiguity of all haplotypes. This feature enables the development of a graph trio binning algorithm that greatly advances over standard trio binning. On three human and five nonhuman datasets, including California redwood with a ~30-Gb hexaploid genome, we show that hifiasm frequently delivers better assemblies than existing tools and consistently outperforms others on haplotype-resolved assembly.


Assuntos
Genoma , Haplótipos , Análise de Sequência de DNA/métodos , Algoritmos
20.
Cancer Causes Control ; 35(4): 605-609, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37975972

RESUMO

BACKGROUND: Head and neck cancer (HNC) has low 5-year survival, and evidence-based recommendations for tertiary prevention are lacking. Aspirin improves outcomes for cancers at other sites, but its role in HNC tertiary prevention remains understudied. METHODS: HNC patients were recruited in the University of Michigan Head and Neck Cancer Specialized Program of Research Excellence (SPORE) from 2003 to 2014. Aspirin data were collected through medical record review; outcomes (overall mortality, HNC-specific mortality, and recurrence) were collected through medical record review, Social Security Death Index, or LexisNexis. Cox proportional hazards models were used to evaluate the associations between aspirin use at diagnosis (yes/no) and HNC outcomes. RESULTS: We observed no statistically significant associations between aspirin and cancer outcome in our HNC patient cohort (n = 1161) (HNC-specific mortality: HR = 0.91, 95% CI = 0.68-1.21; recurrence: HR = 0.94, 95% CI = 0.73-1.19). In analyses stratified by anatomic site, HPV status, and disease stage, we observed no association in any strata examined with the possible exception of a lower risk of recurrence in oropharynx patients (HR = 0.60, 95% CI 0.35-1.04). CONCLUSIONS: Our findings do not support a protective association between aspirin use and cancer-specific death or recurrence in HNC patients, with the possible exception of a lower risk of recurrence in oropharynx patients.


Assuntos
Aspirina , Neoplasias de Cabeça e Pescoço , Humanos , Aspirina/uso terapêutico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Modelos de Riscos Proporcionais
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