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1.
Proc Natl Acad Sci U S A ; 120(11): e2217946120, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36877845

RESUMO

Gas exchange between the atmosphere and ocean interior profoundly impacts global climate and biogeochemistry. However, our understanding of the relevant physical processes remains limited by a scarcity of direct observations. Dissolved noble gases in the deep ocean are powerful tracers of physical air-sea interaction due to their chemical and biological inertness, yet their isotope ratios have remained underexplored. Here, we present high-precision noble gas isotope and elemental ratios from the deep North Atlantic (~32°N, 64°W) to evaluate gas exchange parameterizations using an ocean circulation model. The unprecedented precision of these data reveal deep-ocean undersaturation of heavy noble gases and isotopes resulting from cooling-driven air-to-sea gas transport associated with deep convection in the northern high latitudes. Our data also imply an underappreciated and large role for bubble-mediated gas exchange in the global air-sea transfer of sparingly soluble gases, including O2, N2, and SF6. Using noble gases to validate the physical representation of air-sea gas exchange in a model also provides a unique opportunity to distinguish physical from biogeochemical signals. As a case study, we compare dissolved N2/Ar measurements in the deep North Atlantic to physics-only model predictions, revealing excess N2 from benthic denitrification in older deep waters (below 2.9 km). These data indicate that the rate of fixed N removal in the deep Northeastern Atlantic is at least three times higher than the global deep-ocean mean, suggesting tight coupling with organic carbon export and raising potential future implications for the marine N cycle.

2.
PLoS Pathog ; 19(10): e1011646, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37796819

RESUMO

Congenital cytomegalovirus (cCMV) is the leading infectious cause of neurologic defects in newborns with particularly severe sequelae in the setting of primary CMV infection in the first trimester of pregnancy. The majority of cCMV cases worldwide occur after non-primary infection in CMV-seropositive women; yet the extent to which pre-existing natural CMV-specific immunity protects against CMV reinfection or reactivation during pregnancy remains ill-defined. We previously reported on a novel nonhuman primate model of cCMV in rhesus macaques where 100% placental transmission and 83% fetal loss were seen in CD4+ T lymphocyte-depleted rhesus CMV (RhCMV)-seronegative dams after primary RhCMV infection. To investigate the protective effect of preconception maternal immunity, we performed reinfection studies in CD4+ T lymphocyte-depleted RhCMV-seropositive dams inoculated in late first / early second trimester gestation with RhCMV strains 180.92 (n = 2), or RhCMV UCD52 and FL-RhCMVΔRh13.1/SIVgag, a wild-type-like RhCMV clone with SIVgag inserted as an immunological marker, administered separately (n = 3). An early transient increase in circulating monocytes followed by boosting of the pre-existing RhCMV-specific CD8+ T lymphocyte and antibody response was observed in the reinfected dams but not in control CD4+ T lymphocyte-depleted dams. Emergence of SIV Gag-specific CD8+ T lymphocyte responses in macaques inoculated with the FL-RhCMVΔRh13.1/SIVgag virus confirmed reinfection. Placental transmission was detected in only one of five reinfected dams and there were no adverse fetal sequelae. Viral whole genome, short-read, deep sequencing analysis confirmed transmission of both reinfection RhCMV strains across the placenta with ~30% corresponding to FL-RhCMVΔRh13.1/SIVgag and ~70% to RhCMV UCD52, consistent with the mixed human CMV infections reported in infants with cCMV. Our data showing reduced placental transmission and absence of fetal loss after non-primary as opposed to primary infection in CD4+ T lymphocyte-depleted dams indicates that preconception maternal CMV-specific CD8+ T lymphocyte and/or humoral immunity can protect against cCMV infection.


Assuntos
Infecções por Citomegalovirus , Citomegalovirus , Recém-Nascido , Animais , Feminino , Gravidez , Humanos , Citomegalovirus/genética , Macaca mulatta , Reinfecção , Placenta , Imunidade Inata
3.
PLoS Pathog ; 19(10): e1011378, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37871009

RESUMO

Cytomegalovirus (CMV) is the most common congenital infection and cause of birth defects worldwide. Primary CMV infection during pregnancy leads to a higher frequency of congenital CMV (cCMV) than maternal re-infection, suggesting that maternal immunity confers partial protection. However, poorly understood immune correlates of protection against placental transmission contributes to the current lack of an approved vaccine to prevent cCMV. In this study, we characterized the kinetics of maternal plasma rhesus CMV (RhCMV) viral load (VL) and RhCMV-specific antibody binding and functional responses in a group of 12 immunocompetent dams with acute, primary RhCMV infection. We defined cCMV transmission as RhCMV detection in amniotic fluid (AF) by qPCR. We then leveraged a large group of past and current primary RhCMV infection studies in late-first/early-second trimester RhCMV-seronegative rhesus macaque dams, including immunocompetent (n = 15), CD4+ T cell-depleted with (n = 6) and without (n = 6) RhCMV-specific polyclonal IgG infusion before infection to evaluate differences between RhCMV AF-positive and AF-negative dams. During the first 3 weeks after infection, the magnitude of RhCMV VL in maternal plasma was higher in AF-positive dams in the combined cohort, while RhCMV glycoprotein B (gB)- and pentamer-specific binding IgG responses were lower magnitude compared to AF-negative dams. However, these observed differences were driven by the CD4+ T cell-depleted dams, as there were no differences in plasma VL or antibody responses between immunocompetent AF-positive vs AF-negative dams. Overall, these results suggest that levels of neither maternal plasma viremia nor humoral responses are associated with cCMV following primary maternal infection in healthy individuals. We speculate that other factors related to innate immunity are more important in this context as antibody responses to acute infection likely develop too late to influence vertical transmission. Yet, pre-existing CMV glycoprotein-specific and neutralizing IgG may provide protection against cCMV following primary maternal CMV infection even in high-risk, immunocompromised settings.


Assuntos
Infecções por Citomegalovirus , Citomegalovirus , Animais , Feminino , Humanos , Gravidez , Citomegalovirus/fisiologia , Macaca mulatta , Formação de Anticorpos , Carga Viral , Placenta , Anticorpos Antivirais , Glicoproteínas/metabolismo , Transmissão Vertical de Doenças Infecciosas , Imunoglobulina G/metabolismo
4.
J Immunol ; 211(3): 443-452, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37314415

RESUMO

"Adaptive" NK cells, characterized by FcRγ deficiency and enhanced responsiveness to Ab-bound, virus-infected cells, have been found in certain hCMV-seropositive individuals. Because humans are exposed to numerous microbes and environmental agents, specific relationships between hCMV and FcRγ-deficient NK cells (also known as g-NK cells) have been challenging to define. Here, we show that a subgroup of rhesus CMV (RhCMV)-seropositive macaques possesses FcRγ-deficient NK cells that stably persist and display a phenotype resembling human FcRγ-deficient NK cells. Moreover, these macaque NK cells resembled human FcRγ-deficient NK cells with respect to functional characteristics, including enhanced responsiveness to RhCMV-infected target in an Ab-dependent manner and hyporesponsiveness to tumor and cytokine stimulation. These cells were not detected in specific pathogen-free (SPF) macaques free of RhCMV and six other viruses; however, experimental infection of SPF animals with RhCMV strain UCD59, but not RhCMV strain 68-1 or SIV, led to induction of FcRγ-deficient NK cells. In non-SPF macaques, coinfection by RhCMV with other common viruses was associated with higher frequencies of FcRγ-deficient NK cells. These results support a causal role for specific CMV strain(s) in the induction of FcRγ-deficient NK cells and suggest that coinfection by other viruses further expands this memory-like NK cell pool.


Assuntos
Coinfecção , Infecções por Citomegalovirus , Viroses , Animais , Humanos , Citomegalovirus/genética , Macaca mulatta , Células Matadoras Naturais
5.
N Engl J Med ; 385(9): 815-825, 2021 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-34437784

RESUMO

BACKGROUND: Elexacaftor-tezacaftor-ivacaftor is a small-molecule cystic fibrosis transmembrane conductance regulator (CFTR) modulator regimen shown to be efficacious in patients with at least one Phe508del allele, which indicates that this combination can modulate a single Phe508del allele. In patients whose other CFTR allele contains a gating or residual function mutation that is already effectively treated with previous CFTR modulators (ivacaftor or tezacaftor-ivacaftor), the potential for additional benefit from restoring Phe508del CFTR protein function is unclear. METHODS: We conducted a phase 3, double-blind, randomized, active-controlled trial involving patients 12 years of age or older with cystic fibrosis and Phe508del-gating or Phe508del-residual function genotypes. After a 4-week run-in period with ivacaftor or tezacaftor-ivacaftor, patients were randomly assigned to receive elexacaftor-tezacaftor-ivacaftor or active control for 8 weeks. The primary end point was the absolute change in the percentage of predicted forced expiratory volume in 1 second (FEV1) from baseline through week 8 in the elexacaftor-tezacaftor-ivacaftor group. RESULTS: After the run-in period, 132 patients received elexacaftor-tezacaftor-ivacaftor and 126 received active control. Elexacaftor-tezacaftor-ivacaftor resulted in a percentage of predicted FEV1 that was higher by 3.7 percentage points (95% confidence interval [CI], 2.8 to 4.6) relative to baseline and higher by 3.5 percentage points (95% CI, 2.2 to 4.7) relative to active control and a sweat chloride concentration that was lower by 22.3 mmol per liter (95% CI, 20.2 to 24.5) relative to baseline and lower by 23.1 mmol per liter (95% CI, 20.1 to 26.1) relative to active control (P<0.001 for all comparisons). The change from baseline in the Cystic Fibrosis Questionnaire-Revised respiratory domain score (range, 0 to 100, with higher scores indicating better quality of life) with elexacaftor-tezacaftor-ivacaftor was 10.3 points (95% CI, 8.0 to 12.7) and with active control was 1.6 points (95% CI, -0.8 to 4.1). The incidence of adverse events was similar in the two groups; adverse events led to treatment discontinuation in one patient (elevated aminotransferase level) in the elexacaftor-tezacaftor-ivacaftor group and in two patients (anxiety or depression and pulmonary exacerbation) in the active control group. CONCLUSIONS: Elexacaftor-tezacaftor-ivacaftor was efficacious and safe in patients with Phe508del-gating or Phe508del-residual function genotypes and conferred additional benefit relative to previous CFTR modulators. (Funded by Vertex Pharmaceuticals; VX18-445-104 ClinicalTrials.gov number, NCT04058353.).


Assuntos
Aminofenóis/uso terapêutico , Benzodioxóis/uso terapêutico , Agonistas dos Canais de Cloreto/uso terapêutico , Fibrose Cística/tratamento farmacológico , Indóis/uso terapêutico , Pirazóis/uso terapêutico , Piridinas/uso terapêutico , Quinolinas/uso terapêutico , Adolescente , Adulto , Aminofenóis/efeitos adversos , Benzodioxóis/efeitos adversos , Criança , Agonistas dos Canais de Cloreto/efeitos adversos , Cloretos/análise , Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Método Duplo-Cego , Combinação de Medicamentos , Feminino , Genótipo , Humanos , Indóis/efeitos adversos , Masculino , Pirazóis/efeitos adversos , Piridinas/efeitos adversos , Quinolinas/efeitos adversos , Suor/química
6.
J Neurol Neurosurg Psychiatry ; 95(7): 671-674, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38418217

RESUMO

In 2021, the National Institute for Health and Care Excellence produced an evidence-based guideline on the diagnosis and management of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), a disabling long-term condition of unknown cause. The guideline provides clear support for people living with ME/CFS, their families and carers, and for clinicians. A recent opinion piece published in the journal suggested that there were anomalies in the processing and interpretation of the evidence when developing the guideline and proposed eight areas where these anomalies were thought to have occurred. We outline how these opinions are based on a misreading or misunderstanding of the guideline process or the guideline, which provides a balanced and reasoned approach to the diagnosis and management of this challenging condition.


Assuntos
Síndrome de Fadiga Crônica , Guias de Prática Clínica como Assunto , Humanos , Síndrome de Fadiga Crônica/diagnóstico , Síndrome de Fadiga Crônica/terapia , Medicina Baseada em Evidências , Reino Unido
7.
Proc Natl Acad Sci U S A ; 118(47)2021 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-34799449

RESUMO

It is well established that mantle plumes are the main conduits for upwelling geochemically enriched material from Earth's deep interior. The fashion and extent to which lateral flow processes at shallow depths may disperse enriched mantle material far (>1,000 km) from vertical plume conduits, however, remain poorly constrained. Here, we report He and C isotope data from 65 hydrothermal fluids from the southern Central America Margin (CAM) which reveal strikingly high 3He/4He (up to 8.9RA) in low-temperature (≤50 °C) geothermal springs of central Panama that are not associated with active volcanism. Following radiogenic correction, these data imply a mantle source 3He/4He >10.3RA (and potentially up to 26RA, similar to Galápagos hotspot lavas) markedly greater than the upper mantle range (8 ± 1RA). Lava geochemistry (Pb isotopes, Nb/U, and Ce/Pb) and geophysical constraints show that high 3He/4He values in central Panama are likely derived from the infiltration of a Galápagos plume-like mantle through a slab window that opened ∼8 Mya. Two potential transport mechanisms can explain the connection between the Galápagos plume and the slab window: 1) sublithospheric transport of Galápagos plume material channeled by lithosphere thinning along the Panama Fracture Zone or 2) active upwelling of Galápagos plume material blown by a "mantle wind" toward the CAM. We present a model of global mantle flow that supports the second mechanism, whereby most of the eastward transport of Galápagos plume material occurs in the shallow asthenosphere. These findings underscore the potential for lateral mantle flow to transport mantle geochemical heterogeneities thousands of kilometers away from plume conduits.

8.
J Virol ; 96(3): e0165321, 2022 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-34788083

RESUMO

Rhesus cytomegalovirus (RhCMV) infection of rhesus macaques (Macaca mulatta) is a valuable nonhuman primate model of human CMV (HCMV) persistence and pathogenesis. In vivo studies predominantly use tissue culture-adapted variants of RhCMV that contain multiple genetic mutations compared to wild-type (WT) RhCMV. In many studies, animals have been inoculated by nonnatural routes (e.g., subcutaneous, intravenous) that do not recapitulate disease progression via the normative route of mucosal exposure. Accordingly, the natural history of RhCMV would be more accurately reproduced by infecting macaques with strains of RhCMV that reflect the WT genome using natural routes of mucosal transmission. Here, we tested two WT-like RhCMV strains, UCD52 and UCD59, and demonstrated that systemic infection and frequent, high-titer viral shedding in bodily fluids occurred following oral inoculation. RhCMV disseminated to a broad range of tissues, including the central nervous system and reproductive organs. Commonly infected tissues included the thymus, spleen, lymph nodes, kidneys, bladder, and salivary glands. Histological examination revealed prominent nodular hyperplasia in spleens and variable levels of lymphoid lymphofollicular hyperplasia in lymph nodes. One of six inoculated animals had limited viral dissemination and shedding, with commensurately weak antibody responses to RhCMV antigens. These data suggest that long-term RhCMV infection parameters might be restricted by local innate factors and/or de novo host immune responses in a minority of primary infections. Together, we have established an oral RhCMV infection model that mimics natural HCMV infection. The virological and immunological parameters characterized in this study will greatly inform HCMV vaccine designs for human immunization. IMPORTANCE Human cytomegalovirus (HCMV) is globally ubiquitous with high seroprevalence rates in all communities. HCMV infections can occur vertically following mother-to-fetus transmission across the placenta and horizontally following shedding of virus in bodily fluids in HCMV-infected hosts and subsequent exposure of susceptible individuals to virus-laden fluids. Intrauterine HCMV has long been recognized as an infectious threat to fetal growth and development. Since vertical HCMV infections occur following horizontal HCMV transmission to the pregnant mother, the nonhuman primate model of HCMV pathogenesis was used to characterize the virological and immunological parameters of infection following primary mucosal exposures to rhesus cytomegalovirus.


Assuntos
Infecções por Citomegalovirus/veterinária , Citomegalovirus/fisiologia , Suscetibilidade a Doenças , Interações Hospedeiro-Patógeno , Doenças dos Macacos/imunologia , Doenças dos Macacos/virologia , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Biópsia , DNA Viral , Suscetibilidade a Doenças/imunologia , Interações Hospedeiro-Patógeno/imunologia , Imunoglobulina G/imunologia , Imuno-Histoquímica , Macaca mulatta , Doenças dos Macacos/patologia , Doenças dos Macacos/transmissão , Fases de Leitura Aberta , Especificidade de Órgãos , Carga Viral , Viremia , Eliminação de Partículas Virais
9.
Br J Surg ; 110(8): 966-972, 2023 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-37259179

RESUMO

BACKGROUND: Volume replacement using chest wall perforator flaps (CWPFs) is a promising technique to reduce mastectomy rates without sacrificing function or aesthetics. Owing to limited availability of the technique, only a minority of patients currently have access to CWPF procedures. METHODS: An international web-based survey was disseminated through social media, dedicated webpages, and national and international societies for breast surgery. The survey explored surgeons' attitudes towards CWPFs and their perceived training needs. RESULTS: Of 619 respondents, 88.4 per cent agreed that CWPF surgery was desirable, with one-third offering it and performing a median of 10 (i.q.r. 5-15) procedures annually. They were more likely to be senior (OR 1.35, 95 per cent c.i. 1.18 to 1.55; P < 0.001), with formal oncoplastic training (OR 4.80, 3.09 to 7.48; P < 0.001), and working in larger units (OR 1.18, 1.03 to 1.35; P = 0.018) with a free-flap (OR 1.62, 1.06 to 2.48; P = 0.025) or CWPF (OR 3.02, 1.87 to 4.89; P < 0.001) service available. In cluster and latent class analysis, none showed high cohesion with performance of CWPF surgery. CONCLUSION: There is a discrepancy between perceived importance and availability of CWPF surgery, indicating that optimal training is needed.


Assuntos
Neoplasias da Mama , Mamoplastia , Retalho Perfurante , Parede Torácica , Humanos , Feminino , Mastectomia , Parede Torácica/cirurgia , Neoplasias da Mama/cirurgia , Mamoplastia/métodos , Inquéritos e Questionários , Atitude
10.
J Med Primatol ; 52(1): 53-63, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36151734

RESUMO

INTRODUCTION: Rhesus macaques are natural hosts to multiple viruses including rhesus cytomegalovirus (RhCMV), rhesus rhadinovirus (RRV), and Simian Foamy Virus (SFV). While viral infections are ubiquitous, viral transmissions to uninfected animals are incompletely defined. Management procedures of macaque colonies include cohorts that are Specific Pathogen Free (SPF). Greater understanding of viral transmission would augment SPF protocols. Moreover, vaccine/challenge studies of human viruses would be enhanced by leveraging transmission of macaque viruses to recapitulate expected challenges of human vaccine trials. MATERIALS AND METHODS: This study characterizes viral transmissions to uninfected animals following inadvertent introduction of RhCMV/RRV/SFV-infected adults to a cohort of uninfected juveniles. Following co-housing with virus-positive adults, juveniles were serially evaluated for viral infection. RESULTS: Horizontal viral transmission was rapid and absolute, reaching 100% penetrance between 19 and 78 weeks. CONCLUSIONS: This study provides insights into viral natural histories with implications for colony management and modeling vaccine-mediated immune protection studies.


Assuntos
Vacinas contra Citomegalovirus , Rhadinovirus , Humanos , Animais , Citomegalovirus , Macaca mulatta , Vacinação
11.
Semin Respir Crit Care Med ; 44(2): 242-251, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36623819

RESUMO

Diagnosing cystic fibrosis (CF) in adulthood is not a rare occurrence for CF centers despite the popular belief that the diagnosis is achieved almost universally in childhood by means of newborn screening or early clinical presentation. The purpose of this review article is to highlight specific considerations of adult diagnosis of CF. Obtaining a diagnosis of CF at any age is exceptionally important to ensure optimal treatment, monitoring, and support. In the new era of more personalized treatment with the advent of transformative therapies targeting the underlying protein defect, accurate diagnosis is of increasing importance. This review highlights the diagnostic algorithm leading to a new diagnosis of CF in adults. The diagnosis is usually confirmed in the presence of a compatible clinical presentation, evidence of cystic fibrosis transmembrane conductance regulator (CFTR) protein dysfunction, and/or identification of variants in the CFTR gene believed to alter protein function. Achieving the diagnosis, however, is not always straightforward as CFTR protein function exists on a continuum with different organs displaying varying sensitivity to diminution in function. We highlight the current knowledge regarding the epidemiology of CF diagnosed in adults and outline the various clinical presentations, including pulmonary and extrapulmonary, which are more common in this population. We expand on the stepwise testing procedures that lead to diagnosis, paying particular attention to additional levels of testing which may be required to achieve an accurate diagnosis. There continues to be an important need for both pulmonary and other specialists to be aware of the potential for later presentation of CF, as the improvements in treatment over decades have had large positive impacts on prognosis for people with this condition.


Assuntos
Fibrose Cística , Adulto , Humanos , Fibrose Cística/diagnóstico , Fibrose Cística/genética , Fibrose Cística/tratamento farmacológico , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Testes Genéticos , Mutação , Triagem Neonatal , Prognóstico
12.
Am J Primatol ; 85(1): e23439, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36263518

RESUMO

The endangered mountain gorilla (Gorilla beringei beringei) in Rwanda, Uganda, and the Democratic Republic of Congo is frequently in contact with humans through tourism, research activities, and illegal entry of people into protected gorilla habitat. Herpesviruses, which are ubiquitous in primates, have the potential to be shared in any setting where humans and gorillas share habitat. Based on serological findings and clinical observations of orofacial ulcerated lesions resembling herpetic lesions, an alpha-herpesvirus resembling human herpes simplex virus type 1 (HSV-1) has long been suspected to be present in human-habituated mountain gorillas in the wild. While the etiology of orofacial lesions in the wild has not been confirmed, HSV-1 has been suspected in captively-housed mountain gorillas and confirmed in a co-housed confiscated Grauer's gorilla (Gorilla beringei graueri). To better characterize herpesviruses infecting mountain gorillas and to determine the presence/absence of HSV-1 in the free-living population, we conducted a population-wide survey to test for the presence of orally shed herpesviruses. DNA was extracted from discarded chewed plants collected from 294 individuals from 26 groups, and samples were screened by polymerase chain reaction using pan-herpesvirus and HSV-1-specific assays. We found no evidence that human herpesviruses had infected free-ranging mountain gorillas. However, we found gorilla-specific homologs to human herpesviruses, including cytomegaloviruses (GbbCMV-1 and 2), a lymphocryptovirus (GbbLCV-1), and a new rhadinovirus (GbbRHV-1) with similar characteristics (i.e., timing of primary infection, shedding in multiple age groups, and potential modes of transmission) to their human counterparts, human cytomegalovirus, Epstein-Barr virus and Kaposi's sarcoma-associated herpesvirus, respectively.


Assuntos
Infecções por Vírus Epstein-Barr , Gorilla gorilla , Humanos , Animais , Gorilla gorilla/genética , Herpesvirus Humano 4 , Ruanda/epidemiologia , Uganda
13.
Proc Natl Acad Sci U S A ; 117(25): 13997-14004, 2020 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-32513744

RESUMO

Identifying the origin of noble gases in Earth's mantle can provide crucial constraints on the source and timing of volatile (C, N, H2O, noble gases, etc.) delivery to Earth. It remains unclear whether the early Earth was able to directly capture and retain volatiles throughout accretion or whether it accreted anhydrously and subsequently acquired volatiles through later additions of chondritic material. Here, we report high-precision noble gas isotopic data from volcanic gases emanating from, in and around, the Yellowstone caldera (Wyoming, United States). We show that the He and Ne isotopic and elemental signatures of the Yellowstone gas requires an input from an undegassed mantle plume. Coupled with the distinct ratio of 129Xe to primordial Xe isotopes in Yellowstone compared with mid-ocean ridge basalt (MORB) samples, this confirms that the deep plume and shallow MORB mantles have remained distinct from one another for the majority of Earth's history. Krypton and xenon isotopes in the Yellowstone mantle plume are found to be chondritic in origin, similar to the MORB source mantle. This is in contrast with the origin of neon in the mantle, which exhibits an isotopic dichotomy between solar plume and chondritic MORB mantle sources. The co-occurrence of solar and chondritic noble gases in the deep mantle is thought to reflect the heterogeneous nature of Earth's volatile accretion during the lifetime of the protosolar nebula. It notably implies that the Earth was able to retain its chondritic volatiles since its earliest stages of accretion, and not only through late additions.

14.
J Infect Dis ; 226(4): 585-594, 2022 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-35413121

RESUMO

The development of a vaccine to prevent congenital human cytomegalovirus (HCMV) disease is a public health priority. We tested rhesus CMV (RhCMV) prototypes of HCMV vaccine candidates in a seronegative macaque oral challenge model. Immunogens included a recombinant pentameric complex (PC; gH/gL/pUL128/pUL130/pUL131A), a postfusion gB ectodomain, and a DNA plasmid that encodes pp65-2. Immunization with QS21-adjuvanted PC alone or with the other immunogens elicited neutralizing titers comparable to those elicited by RhCMV infection. Similarly, immunization with all 3 immunogens elicited pp65-specific cytotoxic T-cell responses comparable to those elicited by RhCMV infection. RhCMV readily infected immunized animals and was detected in saliva, blood, and urine after challenge in quantities similar to those in placebo-immunized animals. If HCMV evades vaccine-elicited immunity in humans as RhCMV evaded immunity in macaques, a HCMV vaccine must elicit immunity superior to, or different from, that elicited by the prototype RhCMV vaccine to block horizontal transmission.


Assuntos
Infecções por Citomegalovirus , Vacinas contra Citomegalovirus , Animais , Anticorpos Neutralizantes , Anticorpos Antivirais , Citomegalovirus , Humanos , Macaca mulatta , Proteínas do Envelope Viral
15.
BMC Bioinformatics ; 22(Suppl 14): 631, 2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36384559

RESUMO

BACKGROUND: Decisions in healthcare usually rely on the goodness and completeness of data that could be coupled with heuristics to improve the decision process itself. However, this is often an incomplete process. Structured interviews denominated Delphi surveys investigate experts' opinions and solve by consensus complex matters like those underlying surgical decision-making. Natural Language Processing (NLP) is a field of study that combines computer science, artificial intelligence, and linguistics. NLP can then be used as a valuable help in building a correct context in surgical data, contributing to the amelioration of surgical decision-making. RESULTS: We applied NLP coupled with machine learning approaches to predict the context (words) owning high accuracy from the words nearest to Delphi surveys, used as input. CONCLUSIONS: The proposed methodology has increased the usefulness of Delphi surveys favoring the extraction of keywords that can represent a specific clinical context. It permits the characterization of the clinical context suggesting words for the evaluation process of the data.


Assuntos
Inteligência Artificial , Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/cirurgia , Processamento de Linguagem Natural , Aprendizado de Máquina
16.
PLoS Pathog ; 16(2): e1007968, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32059027

RESUMO

Human cytomegalovirus (HCMV) infection is the leading non-genetic cause of congenital birth defects worldwide. While several studies have addressed the genetic composition of viral populations in newborns diagnosed with HCMV, little is known regarding mother-to-child viral transmission dynamics and how therapeutic interventions may impact within-host viral populations. Here, we investigate how preexisting CMV-specific antibodies shape the maternal viral population and intrauterine virus transmission. Specifically, we characterize the genetic composition of CMV populations in a monkey model of congenital CMV infection to examine the effects of passively-infused hyperimmune globulin (HIG) on viral population genetics in both maternal and fetal compartments. In this study, 11 seronegative, pregnant monkeys were challenged with rhesus CMV (RhCMV), including a group pretreated with a standard potency HIG preparation (n = 3), a group pretreated with a high-neutralizing potency HIG preparation (n = 3), and an untreated control group (n = 5). Targeted amplicon deep sequencing of RhCMV glycoprotein B and L genes revealed that one of the three strains present in the viral inoculum (UCD52) dominated maternal and fetal viral populations. We identified minor haplotypes of this strain and characterized their dynamics. Many of the identified haplotypes were consistently detected at multiple timepoints within sampled maternal tissues, as well as across tissue compartments, indicating haplotype persistence over time and transmission between maternal compartments. However, haplotype numbers and diversity levels were not appreciably different between control, standard-potency, and high-potency pretreatment groups. We found that while the presence of maternal antibodies reduced viral load and congenital infection, it had no apparent impact on intrahost viral genetic diversity at the investigated loci. Interestingly, some minor haplotypes present in fetal and maternal-fetal interface tissues were also identified as minor haplotypes in corresponding maternal tissues, providing evidence for a loose RhCMV mother-to-fetus transmission bottleneck even in the presence of preexisting antibodies.


Assuntos
Anticorpos Antivirais/farmacologia , Infecções por Citomegalovirus , Citomegalovirus/metabolismo , Transmissão Vertical de Doenças Infecciosas , Complicações Infecciosas na Gravidez , Animais , Infecções por Citomegalovirus/tratamento farmacológico , Infecções por Citomegalovirus/metabolismo , Infecções por Citomegalovirus/patologia , Feminino , Macaca mulatta , Gravidez , Complicações Infecciosas na Gravidez/tratamento farmacológico , Complicações Infecciosas na Gravidez/metabolismo , Complicações Infecciosas na Gravidez/patologia
17.
PLoS Pathog ; 16(11): e1008666, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33232376

RESUMO

Cytomegaloviruses (CMVs) are highly adapted to their host species resulting in strict species specificity. Hence, in vivo examination of all aspects of CMV biology employs animal models using host-specific CMVs. Infection of rhesus macaques (RM) with rhesus CMV (RhCMV) has been established as a representative model for infection of humans with HCMV due to the close evolutionary relationships of both host and virus. However, the only available RhCMV clone that permits genetic modifications is based on the 68-1 strain which has been passaged in fibroblasts for decades resulting in multiple genomic changes due to tissue culture adaptations. As a result, 68-1 displays reduced viremia in RhCMV-naïve animals and limited shedding compared to non-clonal, low passage isolates. To overcome this limitation, we used sequence information from primary RhCMV isolates to construct a full-length (FL) RhCMV by repairing all mutations affecting open reading frames (ORFs) in the 68-1 bacterial artificial chromosome (BAC). Inoculation of adult, immunocompetent, RhCMV-naïve RM with the reconstituted virus resulted in significant viremia in the blood similar to primary isolates of RhCMV and furthermore led to high viral genome copy numbers in many tissues at day 14 post infection. In contrast, viral dissemination was greatly reduced upon deletion of genes also lacking in 68-1. Transcriptome analysis of infected tissues further revealed that chemokine-like genes deleted in 68-1 are among the most highly expressed viral transcripts both in vitro and in vivo consistent with an important immunomodulatory function of the respective proteins. We conclude that FL-RhCMV displays in vitro and in vivo characteristics of a wildtype virus while being amenable to genetic modifications through BAC recombineering techniques.


Assuntos
Infecções por Citomegalovirus/virologia , Citomegalovirus/genética , Genoma Viral/genética , Viremia , Animais , Linhagem Celular , Cromossomos Artificiais Bacterianos , Citomegalovirus/patogenicidade , DNA Recombinante , Modelos Animais de Doenças , Feminino , Fibroblastos/virologia , Humanos , Macaca mulatta , Masculino , Mutação , Fases de Leitura Aberta/genética , Filogenia , Especificidade da Espécie
18.
Phys Rev Lett ; 128(4): 047701, 2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-35148146

RESUMO

We demonstrate microwave-mediated distant magnon-magnon coupling on a superconducting circuit platform, incorporating chip-mounted single-crystal Y_{3}Fe_{5}O_{12} (YIG) spheres. Coherent level repulsion and dissipative level attraction between the magnon modes of the two YIG spheres are demonstrated. The former is mediated by cavity photons of a superconducting resonator, and the latter is mediated by propagating photons of a coplanar waveguide. Our results open new avenues toward exploring integrated hybrid magnonic networks for coherent information processing on a quantum-compatible superconducting platform.

19.
Phys Rev Lett ; 128(13): 131801, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35426699

RESUMO

We introduce the Broadband Reflector Experiment for Axion Detection (BREAD) conceptual design and science program. This haloscope plans to search for bosonic dark matter across the [10^{-3},1] eV ([0.24, 240] THz) mass range. BREAD proposes a cylindrical metal barrel to convert dark matter into photons, which a novel parabolic reflector design focuses onto a photosensor. This unique geometry enables enclosure in standard cryostats and high-field solenoids, overcoming limitations of current dish antennas. A pilot 0.7 m^{2} barrel experiment planned at Fermilab is projected to surpass existing dark photon coupling constraints by over a decade with one-day runtime. Axion sensitivity requires <10^{-20} W/sqrt[Hz] sensor noise equivalent power with a 10 T solenoid and 10 m^{2} barrel. We project BREAD sensitivity for various sensor technologies and discuss future prospects.

20.
PLoS Comput Biol ; 17(3): e1008811, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33657095

RESUMO

Forecasting the risk of pathogen spillover from reservoir populations of wild or domestic animals is essential for the effective deployment of interventions such as wildlife vaccination or culling. Due to the sporadic nature of spillover events and limited availability of data, developing and validating robust, spatially explicit, predictions is challenging. Recent efforts have begun to make progress in this direction by capitalizing on machine learning methodologies. An important weakness of existing approaches, however, is that they generally rely on combining human and reservoir infection data during the training process and thus conflate risk attributable to the prevalence of the pathogen in the reservoir population with the risk attributed to the realized rate of spillover into the human population. Because effective planning of interventions requires that these components of risk be disentangled, we developed a multi-layer machine learning framework that separates these processes. Our approach begins by training models to predict the geographic range of the primary reservoir and the subset of this range in which the pathogen occurs. The spillover risk predicted by the product of these reservoir specific models is then fit to data on realized patterns of historical spillover into the human population. The result is a geographically specific spillover risk forecast that can be easily decomposed and used to guide effective intervention. Applying our method to Lassa virus, a zoonotic pathogen that regularly spills over into the human population across West Africa, results in a model that explains a modest but statistically significant portion of geographic variation in historical patterns of spillover. When combined with a mechanistic mathematical model of infection dynamics, our spillover risk model predicts that 897,700 humans are infected by Lassa virus each year across West Africa, with Nigeria accounting for more than half of these human infections.


Assuntos
Reservatórios de Doenças/virologia , Febre Lassa , Vírus Lassa , Modelos Biológicos , África Ocidental , Animais , Animais Selvagens/virologia , Biologia Computacional , Ecologia , Humanos , Febre Lassa/epidemiologia , Febre Lassa/transmissão , Febre Lassa/veterinária , Febre Lassa/virologia , Aprendizado de Máquina , Modelos Estatísticos , Risco , Roedores/virologia
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