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Laser-driven dynamic compression experiments of plastic materials have found surprisingly fast formation of nanodiamonds (ND) via X-ray probing. This mechanism is relevant for planetary models, but could also open efficient synthesis routes for tailored NDs. We investigate the release mechanics of compressed NDs by molecular dynamics simulation of the isotropic expansion of finite size diamond from different P-T states. Analysing the structural integrity along different release paths via molecular dynamic simulations, we found substantial disintegration rates upon shock release, increasing with the on-Hugnoiot shock temperature. We also find that recrystallization can occur after the expansion and hence during the release, depending on subsequent cooling mechanisms. Our study suggests higher ND recovery rates from off-Hugoniot states, e.g., via double-shocks, due to faster cooling. Laser-driven shock compression experiments of polyethylene terephthalate (PET) samples with in situ X-ray probing at the simulated conditions found diamond signal that persists up to 11 ns after breakout. In the diffraction pattern, we observed peak shifts, which we attribute to thermal expansion of the NDs and thus a total release of pressure, which indicates the stability of the released NDs.
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Batborne henipaviruses, such as Nipah virus and Hendra virus, represent a major threat to global health due to their propensity for spillover, severe pathogenicity, and high mortality rate in human hosts. Coupled with the absence of approved vaccines or therapeutics, work with the prototypical species and uncharacterized, emergent species is restricted to high biocontainment facilities. There is a scarcity of such specialized spaces for research, and often the scope and capacity of research which can be conducted at BSL-4 is limited. Therefore, there is a pressing need for innovative life-cycle modeling systems to enable comprehensive research within lower biocontainment settings. This work showcases tetracistronic, transcription and replication competent minigenomes for Nipah virus, Hendra virus, Cedar virus, and Ghana virus, which encode viral proteins facilitating budding, fusion, and receptor binding. We validate the functionality of all encoded viral proteins and demonstrate a variety of applications to interrogate the viral life cycle. Notably, we found that the Cedar virus replicase exhibits remarkable promiscuity, efficiently rescuing minigenomes from all tested henipaviruses. We also apply this technology to GhV, an emergent species which has so far not been isolated in culture. We demonstrate that the reported sequence of GhV is incomplete, but that this missing sequence can be substituted with analogous sequences from other henipaviruses. Use of our GhV system establishes the functionality of the GhV replicase and identifies two antivirals which are highly efficacious against the GhV polymerase.
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Hydrogenated diamond-like carbon (HDLC) is a promising solid lubricant for its superlubricity which can benefit various industrial applications. While HDLC exhibits notable friction reduction in macroscale tests in inert or reducing environmental conditions, ultralow friction is rarely observed at the nanoscale. This study investigates this rather peculiar dependence of HDLC superlubricity on the contact scale. To attain superlubricity, HDLC requires i) removal of ≈2 nm-thick air-oxidized surface layer and ii) shear-induced transformation of amorphous carbon to highly graphitic and hydrogenated structure. The nanoscale wear depth exceeds the typical thickness of the air-oxidized layer, ruling out the possibility of incomplete removal of the air-oxidized layer. Raman analysis of transfer films indicates that shear-induced graphitization readily occurs at shear stresses lower than or comparable to those in the nanoscale test. Thus, the same is expected to occur at the nanoscale test. However, the graphitic transfer films are not detected in ex-situ analyses after nanoscale friction tests, indicating that the graphitic transfer films are pushed out of the nanoscale contact area due to the instability of transfer films within a small contact area. Combining all these observations, this study concludes the retention of highly graphitic transfer films is crucial to achieving HDLC superlubricity.
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Nipah virus (NiV) is a highly lethal, zoonotic Henipavirus (HNV) that causes respiratory and neurological signs and symptoms in humans. Similar to other paramyxoviruses, HNVs mediate entry into host cells through the concerted actions of two surface glycoproteins: a receptor-binding protein (RBP) that mediates attachment and a fusion glycoprotein (F) that triggers fusion in an RBP-dependent manner. NiV uses ephrin-B2 (EFNB2) and ephrin-B3 (EFNB3) as entry receptors. Ghana virus (GhV), a novel HNV identified in a Ghanaian bat, uses EFNB2 but not EFNB3. In this study, we employ a structure-informed approach to identify receptor-interfacing residues and systematically introduce GhV-RBP residues into a NiV-RBP backbone to uncover the molecular determinants of EFNB3 usage. We reveal two regions that severely impair EFNB3 binding by NiV-RBP and EFNB3-mediated entry by NiV pseudotyped viral particles. Further analyses uncovered two-point mutations (NiVN557SGhV and NiVY581TGhV) pivotal for this phenotype. Moreover, we identify NiV interaction with Y120 of EFNB3 as important for the usage of this receptor. Beyond these EFNB3-related findings, we reveal two domains that restrict GhV binding of EFNB2, confirm the HNV-head as an immunodominant target for polyclonal and monoclonal antibodies, and describe putative epitopes for GhV- and NiV-specific monoclonal antibodies. Cumulatively, the work presented here generates useful reagents and tools that shed insight to residues important for NiV usage of EFNB3, reveal regions critical for GhV binding of EFNB2, and describe putative HNV antibody-binding epitopes. IMPORTANCE: Hendra virus and Nipah virus (NiV) are lethal, zoonotic Henipaviruses (HNVs) that cause respiratory and neurological clinical features in humans. Since their initial outbreaks in the 1990s, several novel HNVs have been discovered worldwide, including Ghana virus. Additionally, there is serological evidence of zoonotic transmission, lending way to concerns about future outbreaks. HNV infection of cells is mediated by the receptor-binding protein (RBP) and the Fusion protein (F). The work presented here identifies NiV RBP amino acids important for the usage of ephrin-B3 (EFNB3), a receptor highly expressed in neurons and predicted to be important for neurological clinical features caused by NiV. This study also characterizes epitopes recognized by antibodies against divergent HNV RBPs. Together, this sheds insight to amino acids critical for HNV receptor usage and antibody binding, which is valuable for future studies investigating determinants of viral pathogenesis and developing antibody therapies.
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Infecções por Henipavirus , Henipavirus , Receptores Virais , Humanos , Aminoácidos/genética , Anticorpos Monoclonais/metabolismo , Proteínas de Transporte/metabolismo , Efrina-B3/genética , Efrina-B3/química , Efrina-B3/metabolismo , Epitopos/genética , Epitopos/metabolismo , Gana , Vírus Hendra/metabolismo , Henipavirus/classificação , Henipavirus/genética , Henipavirus/metabolismo , Mutagênese , Vírus Nipah/metabolismo , Proteínas do Envelope Viral/genética , Internalização do Vírus , Receptores Virais/metabolismoRESUMO
Subacute sclerosing panencephalitis (SSPE) is a rare but fatal late neurological complication of measles, caused by persistent measles virus (MeV) infection of the central nervous system. There are no drugs approved for the treatment of SSPE. Here, we followed the clinical progression of a 5-year-old SSPE patient after treatment with the nucleoside analog remdesivir, conducted a post-mortem evaluation of the patient's brain, and characterized the MeV detected in the brain. The quality of life of the patient transiently improved after the first two courses of remdesivir, but a third course had no further clinical effect, and the patient eventually succumbed to his condition. Post-mortem evaluation of the brain displayed histopathological changes including loss of neurons and demyelination paired with abundant presence of MeV RNA-positive cells throughout the brain. Next-generation sequencing of RNA isolated from the brain revealed a complete MeV genome with mutations that are typically detected in SSPE, characterized by a hypermutated M gene. Additional mutations were detected in the polymerase (L) gene, which were not associated with resistance to remdesivir. Functional characterization showed that mutations in the F gene led to a hyperfusogenic phenotype predominantly mediated by N465I. Additionally, recombinant wild-type-based MeV with the SSPE-F gene or the F gene with the N465I mutation was no longer lymphotropic but instead efficiently disseminated in neural cultures. Altogether, this case encourages further investigation of remdesivir as a potential treatment of SSPE and highlights the necessity to functionally understand SSPE-causing MeV.IMPORTANCEMeasles virus (MeV) causes acute, systemic disease and remains an important cause of morbidity and mortality in humans. Despite the lack of known entry receptors in the brain, MeV can persistently infect the brain causing the rare but fatal neurological disorder subacute sclerosing panencephalitis (SSPE). SSPE-causing MeVs are characterized by a hypermutated genome and a hyperfusogenic F protein that facilitates the rapid spread of MeV throughout the brain. No treatment against SSPE is available, but the nucleoside analog remdesivir was recently demonstrated to be effective against MeV in vitro. We show that treatment of an SSPE patient with remdesivir led to transient clinical improvement and did not induce viral escape mutants, encouraging the future use of remdesivir in SSPE patients. Functional characterization of the viral proteins sheds light on the shared properties of SSPE-causing MeVs and further contributes to understanding how those viruses cause disease.
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Monofosfato de Adenosina , Alanina , Vírus do Sarampo , Sarampo , Panencefalite Esclerosante Subaguda , Proteínas Virais , Pré-Escolar , Humanos , Monofosfato de Adenosina/administração & dosagem , Monofosfato de Adenosina/análogos & derivados , Monofosfato de Adenosina/uso terapêutico , Alanina/administração & dosagem , Alanina/análogos & derivados , Alanina/uso terapêutico , Autopsia , Encéfalo/metabolismo , Encéfalo/patologia , Encéfalo/virologia , Progressão da Doença , Evolução Fatal , Genoma Viral/genética , Sequenciamento de Nucleotídeos em Larga Escala , Sarampo/complicações , Sarampo/tratamento farmacológico , Sarampo/virologia , Vírus do Sarampo/efeitos dos fármacos , Vírus do Sarampo/genética , Vírus do Sarampo/metabolismo , Proteínas Mutantes/análise , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Qualidade de Vida , RNA Viral/análise , RNA Viral/genética , Panencefalite Esclerosante Subaguda/tratamento farmacológico , Panencefalite Esclerosante Subaguda/etiologia , Panencefalite Esclerosante Subaguda/virologia , Proteínas Virais/análise , Proteínas Virais/genética , Proteínas Virais/metabolismoRESUMO
OBJECTIVE: Pediatric researchers use Agency for Healthcare Research and Quality (AHRQ) Kids' Inpatient Database (KID) and National Inpatient Sample (NIS) to analyze the national resource use and outcomes of hospitalized children. Inherent KID-NIS sampling design differences may yield disparate findings. We compared discharge counts and length of stay (LOS) between KID and NIS for common and rare reasons for hospitalization. METHODS: Retrospective analysis of differences in discharges counts and geometric mean LOS for children ages 0-20 years from KID and NIS in 2019, measured for normal newborns and 331 additional reasons for admission, distinguished by All-Payer Refined Diagnosis Related Groups (APR-DRG) and categorized in deciles by annual discharge volume. We followed AHRQ instructions for data clustering, stratification, and weighting to accommodate the KID and NIS designs, including random samples of 80% and 20% of pediatric discharges, respectively, per hospital. RESULTS: KID-NIS differences in national estimates for total annual discharge counts differed by only 0.5% for normal newborns and 3.7% for all other admission reasons in children. KID-NIS differences remained small aside from reasons for admission in the two lowest volume deciles: 9.5% (SD 7.9%) for admission volumes 200-520; 41.1% (SD 64.2%) for volumes <200. KID-NIS LOS differences for these two-lowest volume deciles were 7.9% (SD 7.1%) and 26.0% (SD 29.3%), respectively. CONCLUSIONS: Although KID-NIS differences in discharge counts and LOS were small for high-volume admissions, the differences increased with reasons for admission that had annual discharge volumes approximately 500 or less. For study populations with discharge counts <500, KID may be preferred, given its higher sampling of discharges per hospital.
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Hospitalização , Pacientes Internados , Criança , Humanos , Recém-Nascido , Estados Unidos , Estudos Retrospectivos , Tempo de Internação , Alta do Paciente , Bases de Dados FactuaisRESUMO
C-reactive protein (CRP) is an acute phase, predominantly hepatically synthesized protein, secreted in response to cytokine signaling at sites of tissue injury or infection with the physiological function of acute pro-inflammatory response. Historically, CRP has been classified as a mediator of the innate immune system, acting as a pattern recognition receptor for phosphocholine-containing ligands. For decades, CRP was envisioned as a single, non-glycosylated, multi-subunit protein arranged non-covalently in cyclic symmetry around a central void. Over the past few years, however, CRP has been shown to exist in at least three distinct isoforms: 1.) a pentamer of five identical globular subunits (pCRP), 2.) a modified monomer (mCRP) resulting from a conformational change when subunits are dissociated from the pentamer, and 3.) a transitional isoform where the pentamer remains intact but is partially changed to express mCRP structural characteristics (referred to as pCRP* or mCRPm). The conversion of pCRP into mCRP can occur spontaneously and is observed under commonly used experimental conditions. In careful consideration of experimental design used in published reports of in vitro pro- and anti-inflammatory CRP bioactivities, we herein provide an interpretation of how distinctive CRP isoforms may have affected reported results. We argue that pro-inflammatory amplification mechanisms are consistent with the biofunction of mCRP, while weak anti-inflammatory mechanisms are consistent with pCRP. The interplay of each CRP isoform with specific immune cells (platelets, neutrophils, monocytes, endothelial cells, natural killer cells) and mechanisms of the innate immune system (complement), as well as differences in mCRP and pCRP ligand recognition and effector functions are discussed. This review will serve as a revised understanding of the structure-function relationship between CRP isoforms as related to inflammation and innate immunity mechanisms.
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Proteína C-Reativa , Células Endoteliais , Humanos , Proteína C-Reativa/metabolismo , Células Endoteliais/metabolismo , Inflamação , Isoformas de Proteínas/metabolismo , ImunidadeRESUMO
BACKGROUND: Computational models of fibrosis-mediated, re-entrant left atrial (LA) arrhythmia can identify possible substrate for persistent atrial fibrillation (AF) ablation. Contemporary models use a 1-size-fits-all approach to represent electrophysiological properties, limiting agreement between simulations and patient outcomes. OBJECTIVES: The goal of this study was to test the hypothesis that conduction velocity (Ï´) modulation in persistent AF models can improve simulation agreement with clinical arrhythmias. METHODS: Patients with persistent AF (n = 37) underwent ablation and were followed up for ≥2 years to determine post-ablation outcomes: AF, atrial flutter (AFL), or no recurrence. Patient-specific LA models (n = 74) were constructed using pre-ablation and ≥90 days' post-ablation magnetic resonance imaging data. Simulated pacing gauged in silico arrhythmia inducibility due to AF-like rotors or AFL-like macro re-entrant tachycardias. A physiologically plausible range of Ï´ values (±10 or 20% vs. baseline) was tested, and model/clinical agreement was assessed. RESULTS: Fifteen (41%) patients had a recurrence with AF and 6 (16%) with AFL. Arrhythmia was induced in 1,078 of 5,550 simulations. Using baseline Ï´, model/clinical agreement was 46% (34 of 74 models), improving to 65% (48 of 74) when any possible Ï´ value was used (McNemar's test, P = 0.014). Ï´ modulation improved model/clinical agreement in both pre-ablation and post-ablation models. Pre-ablation model/clinical agreement was significantly greater for patients with extensive LA fibrosis (>17.2%) and an elevated body mass index (>32.0 kg/m2). CONCLUSIONS: Simulations in persistent AF models show a 41% relative improvement in model/clinical agreement when Ï´ is modulated. Patient-specific calibration of Ï´ values could improve model/clinical agreement and model usefulness, especially in patients with higher body mass index or LA fibrosis burden. This could ultimately facilitate better personalized modeling, with immediate clinical implications.
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Fibrilação Atrial , Flutter Atrial , Humanos , Fibrilação Atrial/cirurgia , Átrios do Coração/diagnóstico por imagem , Átrios do Coração/cirurgia , Flutter Atrial/cirurgia , Fibrose , Simulação por ComputadorRESUMO
Background Postablation arrhythmia recurrence occurs in ~40% of patients with persistent atrial fibrillation. Fibrotic remodeling exacerbates arrhythmic activity in persistent atrial fibrillation and can play a key role in reentrant arrhythmia, but emergent interaction between nonconductive ablation-induced scar and native fibrosis (ie, residual fibrosis) is poorly understood. Methods and Results We conducted computational simulations in pre- and postablation left atrial models reconstructed from late gadolinium enhanced magnetic resonance imaging scans to test the hypothesis that ablation in patients with persistent atrial fibrillation creates new substrate conducive to recurrent arrhythmia mediated by anchored reentry. We trained a random forest machine learning classifier to accurately pinpoint specific nonconductive tissue regions (ie, areas of ablation-delivered scar or vein/valve boundaries) with the capacity to serve as substrate for anchored reentry-driven recurrent arrhythmia (area under the curve: 0.91±0.03). Our analysis suggests there is a distinctive nonconductive tissue pattern prone to serving as arrhythmogenic substrate in postablation models, defined by a specific size and proximity to residual fibrosis. Conclusions Overall, this suggests persistent atrial fibrillation ablation transforms substrate that favors functional reentry (ie, rotors meandering in excitable tissue) into an arrhythmogenic milieu more conducive to anchored reentry. Our work also indicates that explainable machine learning and computational simulations can be combined to effectively probe mechanisms of recurrent arrhythmia.
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Fibrilação Atrial , Ablação por Cateter , Humanos , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/cirurgia , Fibrilação Atrial/patologia , Cicatriz , Átrios do Coração/diagnóstico por imagem , Átrios do Coração/cirurgia , Átrios do Coração/patologia , Fibrose , Simulação por Computador , Aprendizado de Máquina , Ablação por Cateter/efeitos adversos , Ablação por Cateter/métodos , Recidiva , Resultado do TratamentoRESUMO
INTRODUCTION: Late-gadolinium enhancement magnetic resonance (LGE-MRI) imaging is increasingly used in management of atrial fibrillation (AFib) patients. Here, we assess the usefulness of LGE-MRI-based fibrosis quantification to predict arrhythmia recurrence in patients undergoing cryoballoon ablation. Our secondary goal was to compare two widely used fibrosis quantification methods. METHODS: In 102 AF patients undergoing LGE-MRI and cryoballoon ablation (mean age 62 years; 64% male; 59% paroxysmal AFib), atrial fibrosis was quantified using the pixel intensity histogram (PIH) and image intensity ratio (IIR) methods. PIH segmentations were completed by a third-party provider as part of the standard of care at our hospital; Image intensity ratio (IIR) segmentations of the same scans were carried out in our lab using a commercially available software package. Fibrosis burdens and spatial distributions for the two methods were compared. Patients were followed prospectively for recurrent arrhythmia following ablation. RESULTS: Average PIH fibrosis was 15.6 ± 5.8% of the left atrial (LA) volume. Depending on threshold (IIRthr ), the average IIR fibrosis (% of LA wall surface area) ranged from 5.0 ± 7.2% (IIRthr = 1.2) to 37.4 ± 10.9% (IIRthr = 0.97). An IIRthr of 1.03 demonstrated the greatest agreement between the methods, but spatial overlap of fibrotic areas delineated by the two methods was modest (Sorenson Dice coefficient: 0.49). Fourty-two patients (41.2%) had recurrent arrhythmia. PIH fibrosis successfully predicted recurrence (HR 1.07; p = .02) over a follow-up period of 362 ± 149 days; regardless of IIRthr , IIR fibrosis did not predict recurrence. CONCLUSIONS: PIH-based volumetric assessment of atrial fibrosis was modestly predictive of arrhythmia recurrence following cryoballoon ablation in this cohort. IIR-based fibrosis was not predictive of recurrence for any of the IIRthr values tested, and the overlap in designated areas of fibrosis between the PIH and IIR methods was modest. Caution must therefore be exercised when interpreting LA fibrosis from LGE-MRI, since the values and spatial pattern are methodology-dependent.
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Fibrilação Atrial , Ablação por Cateter , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/cirurgia , Fibrilação Atrial/patologia , Meios de Contraste , Gadolínio , Imageamento por Ressonância Magnética/métodos , Átrios do Coração/diagnóstico por imagem , Átrios do Coração/cirurgia , Átrios do Coração/patologia , Fibrose , Ablação por Cateter/métodosRESUMO
Global metagenomic surveys have revealed that bats host a diverse array of paramyxoviruses, including species from at least five major genera. An essential determinant of successful spillover is the entry of a virus into a new host. We evaluate the role of receptor usage in the zoonotic potential of bat-borne henipaviruses, morbilliviruses, pararubulaviruses, orthorubulaviruses, and jeilongviruses; successful spillover into humans depends upon compatibility of a respective viral attachment protein with its cognate receptor. We also emphasize the importance of postentry restrictions in preventing spillover. Metagenomics and characterization of newly identified paramyxoviruses have greatly improved our understanding of spillover determinants, allowing for better forecasts of which bat-borne viruses may pose the greatest risk for cross-species transmission into humans.
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Quirópteros , Animais , Humanos , Adaptação ao Hospedeiro , Ligação Viral , Metagenômica , Especificidade de Hospedeiro , FilogeniaRESUMO
STUDY QUESTION: Are chromosome abnormalities detected at Day 3 post-fertilization predominantly retained in structures of the blastocyst other than the inner cell mass (ICM), where chromosomally normal cells are preferentially retained? SUMMARY ANSWER: In human embryos, aneuploid cells are sequestered away from the ICM, partly to the trophectoderm (TE) but more significantly to the blastocoel fluid within the blastocoel cavity (Bc) and to peripheral cells (PCs) surrounding the blastocyst during Day 3 to Day 5 progression. WHAT IS KNOWN ALREADY: A commonly held dogma in all diploid eukaryotes is that two gametes, each with 'n' chromosomes (23 in humans), fuse to form a '2n' zygote (46 in humans); a state that remains in perpetuity for all somatic cell divisions. Human embryos, however, display high levels of chromosomal aneuploidy in early stages that reportedly declines from Day 3 (cleavage stage) to Day 5 (blastocyst) post-fertilization. While this observation may be partly because of aneuploid embryonic arrest before blastulation, it could also be due to embryo 'normalization' to a euploid state during blastulation. If and how this normalization occurs requires further investigation. STUDY DESIGN, SIZE, DURATION: A total of 964 cleavage-stage (Day 3) embryos underwent single-cell biopsy and diagnosis for chromosome constitution. All were maintained in culture, assessing blastulation rate, both for those assessed euploid and aneuploid. Pregnancy rate was assessed for those determined euploid, blastulated and subsequently transferred. For those determined aneuploid and blastulated (174 embryos), ICM (all 174 embryos), TE (all 174), Bc (47 embryos) and PC (38 embryos) were analyzed for chromosome constitution. Specifically, concordance with the original Day 3 diagnosis and determination if any 'normalized' to euploid karyotypes within all four structures was assessed. PARTICIPANTS/MATERIALS, SETTING, METHODS: All patients (144 couples) were undergoing routine preimplantation genetic testing for aneuploidy in three IVF clinical settings. Cleavage-stage biopsy preceded chromosome analysis by next-generation sequencing. All patients provided informed consent. Additional molecular testing was carried out on blastocyst embryos and was analyzed for up to four embryonic structures (ICM, TE, Bc and PC). MAIN RESULTS AND THE ROLE OF CHANCE: Of 463/964 embryos (48%) diagnosed as euploid at Day 3, 70% blastulated (leading to a 59% pregnancy rate) and 30% degenerated. Conversely, of the 501 (52%) diagnosed as aneuploid, 65% degenerated and 35% (174) blastulated, a highly significant difference (P < 0.0001). Of the 174 that blastulated, the ratio of '(semi)concordant-aneuploid' versus 'normalized-euploid' versus 'other-aneuploid' embryos was, respectively, 39%/57%/3% in the ICM; 49%/48%/3% in the TE; 78%/21%/0% in the PC; and 83%/10%/5% in the Bc. The TE karyotype therefore has a positive predictive value of 86.7% in determining that of the ICM, albeit with marginally higher aneuploid rates of abnormalities (P = .071). Levels of abnormality in Bc/PC were significantly higher (P < 0.0001) versus the ploidy of the ICM and TE and nearly all chromosome abnormalities were (at least partially) concordant with Day 3 diagnoses. LIMITATIONS, REASONS FOR CAUTION: The results only pertain to human IVF embryos so extrapolation to the in vivo situation and to other species is not certain. We acknowledge (rather than lineage-specific survival, as we suggest here) the possibility of other mechanisms, such as lineage-specific movement of cells, during blastulation. Ethical considerations, however, make investigating this mechanism difficult on human embryos. WIDER IMPLICATIONS OF THE FINDINGS: Mosaic human cleavage-stage embryos can differentiate into a euploid ICM where euploid cell populations predominate. Sequestering of aneuploid cells/nuclei to structures no longer involved in fetal development has important implications for preimplantation and prenatal genetic testing. These results also challenge previous fundamental understandings of mitotic fidelity in early human development and indicate a complex and fluid nature of the human embryonic genome. STUDY FUNDING/COMPETING INTEREST(S): This research was funded by Organon Pharmaceuticals and Merck Serono by grants to W.G.K. W.G.K. is also an employee of AdvaGenix, who could, potentially, indirectly benefit financially from publication of this manuscript. R.C.M. is supported by the National Institute of General Medical Sciences of the National Institutes of Health under award number R35GM133747. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health. D.K.G. provides paid consultancy services for Care Fertility. TRIAL REGISTRATION NUMBER: : N/A.
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Diagnóstico Pré-Implantação , Gravidez , Feminino , Humanos , Diagnóstico Pré-Implantação/métodos , Blastocisto , Aberrações Cromossômicas , Aneuploidia , Cariótipo , FetoRESUMO
Extreme conditions inside ice giants such as Uranus and Neptune can result in peculiar chemistry and structural transitions, e.g., the precipitation of diamonds or superionic water, as so far experimentally observed only for pure CâH and H2O systems, respectively. Here, we investigate a stoichiometric mixture of C and H2O by shock-compressing polyethylene terephthalate (PET) plastics and performing in situ x-ray probing. We observe diamond formation at pressures between 72 ± 7 and 125 ± 13 GPa at temperatures ranging from ~3500 to ~6000 K. Combining x-ray diffraction and small-angle x-ray scattering, we access the kinetics of this exotic reaction. The observed demixing of C and H2O suggests that diamond precipitation inside the ice giants is enhanced by oxygen, which can lead to isolated water and thus the formation of superionic structures relevant to the planets' magnetic fields. Moreover, our measurements indicate a way of producing nanodiamonds by simple laser-driven shock compression of cheap PET plastics.
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Devices based on arrays of interconnected magnetic nano-rings with emergent magnetization dynamics have recently been proposed for use in reservoir computing applications, but for them to be computationally useful it must be possible to optimise their dynamical responses. Here, we use a phenomenological model to demonstrate that such reservoirs can be optimised for classification tasks by tuning hyperparameters that control the scaling and input-rate of data into the system using rotating magnetic fields. We use task-independent metrics to assess the rings' computational capabilities at each set of these hyperparameters and show how these metrics correlate directly to performance in spoken and written digit recognition tasks. We then show that these metrics, and performance in tasks, can be further improved by expanding the reservoir's output to include multiple, concurrent measures of the ring arrays' magnetic states.
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Objectives The aim of this study was to assess the mortality and predictive factors in patients presenting with a pH<7.0 to the emergency department (ED). Methods A retrospective study of patients presenting to the ED of University Hospital Galway with a pH<7.0 from January 2014 to December 2017 was performed. A pH<7.0 on arrival to the ED from either an arterial or venous sample as measured by the blood gas analyser machine were assessed for inclusion. Results A total of 130 patients presented to ED over a 4-year period, with a mean age of 58 ±20 years. Eighty-one (63%) patients of the total cohort were male. In terms of aetiology of presentation, 66 (51%) cases were from cardiac arrest (CA), while the remaining 64 (49%) cases were non-cardiac arrest (NCA) related. Twenty-eight-day mortality was 69.5% overall, with significant mortality in the CA group (89%) compared to the NCA group (48%) (p<0.00). A modified early warning score (MEWS) (odds ratio [OR] 1.37, 95% CI: 1.18-1.59) and PCO2 ([OR] 1.35, 95% CI: 1.08-1.68.) were predictive of mortality. Conclusion In patients presenting to the ED with a pH of <7.0 the overall mortality was 69.5%, with survival more likely in NCA aetiologies. Mortality was associated with higher pCO2 and MEWS.
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Serviço Hospitalar de Emergência , Parada Cardíaca , Adulto , Idoso , Feminino , Mortalidade Hospitalar , Humanos , Concentração de Íons de Hidrogênio , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Índice de Gravidade de DoençaRESUMO
During the detailed design phase of an aerospace program, one of the most important consistency checks is to ensure that no two distinct objects occupy the same physical space. Since exact geometrical modeling is usually intractable, geometry models are discretized, which often introduces small interferences not present in the fully detailed model. In this paper, we focus on computing the depth of the interference, so that these false positive interferences can be removed, and attention can be properly focused on the actual design. Specifically, we focus on efficiently computing the penetration depth between two polyhedra, which is a well-studied problem in the computer graphics community. We formulate the problem as a constrained five-variable global optimization problem, and then derive an equivalent unconstrained, two-variable nonsmooth problem. To solve the optimization problem, we apply a popular stochastic multistart optimization algorithm in a novel way, which exploits the advantages of each problem formulation simultaneously. Numerical results for the algorithm, applied to 14 randomly generated pairs of penetrating polytopes, illustrate both the effectiveness and efficiency of the method.
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OBJECTIVE: A comprehensive quality improvement (QI) program aimed at all aspects of patient care after pituitary surgery was initiated at a single center. This initiative was guided by standard quality principles to improve patient outcomes and optimize healthcare value. The programmatic goal was to discharge most elective patients within 1 day after surgery, improve patient safety, and limit unplanned readmissions. The program is described, and its effect on patient outcomes and hospital financial performance over a 5-year period are investigated. METHODS: Details of the patient care pathway are presented. Foundational elements of the QI program include evidence-based care pathways (e.g., for hyponatremia and pain), an in-house research program designed to fortify care pathways, patient education, expectation setting, multidisciplinary team care, standard order sets, high-touch postdischarge care, outcomes auditing, and a patient navigator, among other elements. Length of stay (LOS), outcome variability, 30-day unplanned readmissions, and hospital financial performance were identified as surrogate endpoints for healthcare value for the surgical epoch. To assess the effect of these protocols, all patients undergoing elective transsphenoidal surgery for pituitary tumors and Rathke's cleft cysts between January 2015 and December 2019 were reviewed. RESULTS: A total of 609 adult patients who underwent elective surgery by experienced pituitary surgeons were identified. Patient demographics, comorbidities, and payer mix did not change significantly over the study period (p ≥ 0.10). The mean LOS was significantly shorter in 2019 versus 2015 (1.6 ± 1.0 vs 2.9 ± 2.2 midnights, p < 0.001). The percentage of patients discharged after 1 midnight was significantly higher in 2019 versus 2015 (75.4% vs 15.6%, p < 0.001). The 30-day unplanned hospital readmission rate decreased to 2.8% in 2019 from 8.3% in 2015. Per-patient hospital profit increased 71.3% ($10,613 ± $19,321 in 2015; $18,180 ± $21,930 in 2019), and the contribution margin increased 42.3% ($18,925 ± $19,236 in 2015; $26,939 ± $22,057 in 2019), while costs increased by only 3.4% ($18,829 ± $6611 in 2015; $19,469 ± $4291 in 2019). CONCLUSIONS: After implementation of a comprehensive pituitary surgery QI program, patient outcomes significantly improved, outcome variability decreased, and hospital financial performance was enhanced. Future studies designed to evaluate disease remission, patient satisfaction, and how the surgeon learning curve may synergize with other quality efforts may provide additional context.
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Hair length can be a highly variable trait within the Felis catus species, varying between and within different cat breeds. Previous research has demonstrated this variability is due to recessive mutations within the fibroblast growth factor 5 (FGF5) gene. Following a genetic screen, four longhaired Maine Coons were identified that had only one copy of a known FGF5 mutation. We performed DNA sequencing on samples from two of these Maine Coons and identified a missense mutation in FGF5 c.577G > A p.Ala193Thr. Genetic screening via restriction digest was then performed on samples from the other two Maine Coons and an additional 273 cats of various breeds. This screening found that only the two additional Maine Coons were heterozygous for the novel variant. Furthermore, the novel variant was not identified after in silico analysis of 68 whole genome cat sequences from various breeds, demonstrating that this novel mutation is most likely a breed-specific variant for the Maine Coon, contributing to the longhair phenotype in about 3% of these cats.
Assuntos
Pelo Animal/anatomia & histologia , Gatos/genética , Fator 5 de Crescimento de Fibroblastos/genética , Mutação de Sentido Incorreto , Animais , Gatos/anatomia & histologia , Feminino , Fator 5 de Crescimento de Fibroblastos/química , Heterozigoto , Masculino , LinhagemRESUMO
Objective Presently, there are no standards for reporting outcomes of endoscopic endonasal skull base reconstruction (ESBR). This is problematic as a lack of consistent reporting makes synthesizing findings in systematic reviews and meta-analysis challenging. Thus, the aim of this study was to systematically review and describe the patterns of reporting outcomes in ESBR as a foundation for developing reporting guidelines. Study Design Present study is a systematic review. Methods Embase, PubMed, CINAHL, Cochrane Library, and Web of Science were searched for all publications with ≥25 patients and a focus on ESBR. The reporting patterns of each study's variables and outcomes were assessed. Results A total of 112 studies were included in the review. The most commonly reported demographic variables were the number of included patients ( n = 112, 100%) and types of pathologies treated ( n = 104, 92.9%). Meanwhile, the most routinely described preoperative variable was history of prior treatment ( n = 48, 42.9%). Type of reconstruction was a commonly reported intraoperative variable ( n = 110, 98.2%), though the rate of intraoperative cerebrospinal fluid (CSF) leak was noted in only 76 studies (67.9%). With regard to postoperative outcomes, postoperative CSF leak rate was routinely provided ( n = 101, 90.2%), but reporting of other surgical complications was more inconsistent. Ultimately, of the 43 variables and outcomes reviewed, a median of 12 (range: 4-22) was reported in each study. Conclusion There is significant heterogeneity in the outcomes reported in studies relating to ESBR. This highlights the need for the development of standard reporting guidelines to minimize bias and improve interstudy comparability.
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BACKGROUND: Postoperative prophylactic antibiotics are commonly used in pituitary surgery, but evidence supporting their use is lacking, which has implications for antibiotic stewardship. OBJECTIVE: To evaluate whether receipt of postoperative oral antibiotics results in superior sinonasal quality of life (QOL) compared with placebo among patients who undergo endoscopic endonasal transsphenoidal pituitary surgery. METHODS: Patients were randomized to receive either oral placebo or cefdinir (trimethoprim-sulfamethoxazole in patients intolerant to cefdinir) for 7 d after surgery. They were monitored for 12 wk. The primary outcome measure was sinonasal QOL at 2 wk on the Anterior Skull Base Nasal Inventory-12. Supplementary end points included sinonasal QOL reported on the Sinonasal Outcome Test-22 and objective endoscopy scores to assess nasal healing according to the Lund-Kennedy method. RESULTS: A total of 461 patients were screened, 131 were randomized, and 113 (placebo arm: 55; antibiotic arm: 58) were analyzed. There was no clinically meaningful or statistically significant difference in sinonasal QOL at any measured time point (P ≥ .24) using either instrument. Nasal cavity endoscopy scores were not significantly different at 1 to 2 wk after surgery (P = .25) or at 3 to 4 wk after surgery (P = .08). CONCLUSION: Postoperative prophylactic oral antibiotics did not result in superior sinonasal QOL compared with placebo among patients who underwent standard endoscopic transsphenoidal surgery.