ABSTRACT
A reliable source of identical (indistinguishable) photons is a prerequisite for exploiting interference effects, which is a necessary component for linear optical based quantum computing, and applications thereof such as Boson sampling. Generally speaking, the degree of distinguishability will determine the efficacy of the particular approach, for example by limiting the fidelity of constructed resource states, or reducing the complexity of an optical circuits output distribution. It is therefore of great practical relevance to engineer heralded sources of highly pure and indistinguishable photons. Inspired by magic state distillation, we present a protocol using standard linear optics which can be used to increase the indistinguishability of a photon source, to arbitrary accuracy. In particular, in the asymptotic limit of small error ε, to reduce the error to ε^{'}<ε requires O((ε/ε^{'})^{2}) photons. We demonstrate the scheme is robust to detection and control errors in the optical components, and discuss the effect of other error sources.
ABSTRACT
Background: Critical care patients receive 50% of gastrostomy tubes placed in the United States. Several gastrostomy placement methods exist, however care processes remain variable and often lack health system cost effectiveness. No data exists on efficiency or cost impact of performing bedside percutaneous ultrasound gastrostomy (PUG) on patients with ventilator-dependent respiratory failure. This study's objective was to determine if implementing bedside PUG would positively impact efficiency and cost outcomes in intensive care unit (ICU) patients compared to usual care gastrostomy. Design and Methods: This is a retrospective cohort study of patients with ventilator-dependent respiratory failure who received a gastrostomy consult or procedure in the ICU. Patients received PUG or usual care gastrostomy, determined by the presiding attending's skillset, and both groups were compared across patients' demographics, clinical characteristics and outcomes. Primary outcomes were length of stay (LOS) and total hospital costs. Results: A total of 88 patients were included in the analysis, 45 patients in the PUG group and 43 in the usual care gastrostomy group. No differences were observed in demographic and clinical characteristics. Patients who received PUG had a significantly shorter mean ICULOS and hospital LOS, with reductions of 5.0 and 8.7 days, respectively. Total hospital costs were significantly reduced in the PUG group, with a cost savings of US $26,621 per patient. No differences in mortality or discharge disposition were observed. PUG patients received concomitant percutaneous dilatation tracheostomy (PDT) and PUG ("TPUG") 70% of the time, whereas no usual care patients received concomitant procedures. Off-hour procedures occurred in 53.3% of PUG and 4.6% of usual care gastrostomy. Conclusions: This study demonstrates bedside PUG leads to decreased LOS and total hospital costs in patients with ventilator-dependent respiratory failure. Hospital costs were significantly reduced with a per patient savings of $26,621 compared to usual care gastrostomy.
Subject(s)
Hospital Costs , Respiratory Insufficiency , Humans , Length of Stay , Gastrostomy/methods , Retrospective Studies , Intensive Care Units , Critical CareABSTRACT
Neonatal AAV9-gene therapy of the lysosomal enzyme galactosylceramidase (GALC) significantly ameliorates central and peripheral neuropathology, prolongs survival, and largely normalizes motor deficits in Twitcher mice. Despite these therapeutic milestones, new observations identified the presence of multiple small focal demyelinating areas in the brain after 6-8 months. These lesions are in stark contrast to the diffuse, global demyelination that affects the brain of naive Twitcher mice. Late-onset lesions exhibited lysosomal alterations with reduced expression of GALC and increased psychosine levels. Furthermore, we found that lesions were closely associated with the extravasation of plasma fibrinogen and activation of the fibrinogen-BMP-SMAD-GFAP gliotic response. Extravasation of fibrinogen correlated with tight junction disruptions of the vasculature within the lesioned areas. The lesions were surrounded by normal appearing white matter. Our study shows that the dysregulation of therapeutic GALC was likely driven by the exhaustion of therapeutic AAV episomal DNA within the lesions, paralleling the presence of proliferating oligodendrocyte progenitors and glia. We believe that this is the first demonstration of diminishing expression in vivo from an AAV gene therapy vector with detrimental effects in the brain of a lysosomal storage disease animal model. The development of this phenotype linking localized loss of GALC activity with relapsing neuropathology in the adult brain of neonatally AAV-gene therapy-treated Twitcher mice identifies and alerts to possible late-onset reductions of AAV efficacy, with implications to other genetic leukodystrophies.
Subject(s)
Galactosylceramidase/genetics , Genetic Therapy/methods , Leukodystrophy, Globoid Cell/pathology , White Matter/pathology , Animals , Animals, Newborn , Cells, Cultured , Dependovirus/genetics , Disease Models, Animal , Female , Fibrinogen/metabolism , Galactosylceramidase/metabolism , Genetic Vectors/administration & dosage , Leukodystrophy, Globoid Cell/blood , Leukodystrophy, Globoid Cell/genetics , Leukodystrophy, Globoid Cell/therapy , Male , Mice , RecurrenceABSTRACT
Exposure of nanoparticles in a porous medium, such as a hydrogel, to low-intensity ultrasound has been observed to dramatically enhance particle penetration rate. Enhancement of nanoparticle penetration is a key issue affecting applications such as biofilm mitigation and targeted drug delivery in human tissue. The current study used fluorescent imaging to obtain detailed experimental measurements of the effect of ultrasound amplitude and frequency on diffusion of nanoparticles of different diameters in an agarose hydrogel, which is often used as a simulant for biofilms and biological tissues. We demonstrate that the acoustic enhancement occurs via the phenomenon of oscillatory diffusion, in which a combination of an oscillatory flow together with random hindering of the particles by interaction with hydrogel proteins induces a stochastic random walk of the particles. The measured variation of acoustic diffusion coefficients with amplitude and frequency were used to validate a previous statistical theory of oscillatory diffusion based on the continuous time random walk approach.
Subject(s)
Hydrogels , Nanoparticles , Biofilms , Diffusion , Humans , Nanoparticles/metabolism , SepharoseABSTRACT
N-linked glycosylation in monoclonal antibodies (mAbs) is crucial for structural and functional properties of mAb therapeutics, including stability, pharmacokinetics, safety and clinical efficacy. The biopharmaceutical industry currently lacks tools to precisely control N-glycosylation levels during mAb production. In this study, we engineered Chinese hamster ovary cells with synthetic genetic circuits to tune N-glycosylation of a stably expressed IgG. We knocked out two key glycosyltransferase genes, α-1,6-fucosyltransferase (FUT8) and ß-1,4-galactosyltransferase (ß4GALT1), genomically integrated circuits expressing synthetic glycosyltransferase genes under constitutive or inducible promoters and generated antibodies with concurrently desired fucosylation (0-97%) and galactosylation (0-87%) levels. Simultaneous and independent control of FUT8 and ß4GALT1 expression was achieved using orthogonal small molecule inducers. Effector function studies confirmed that glycosylation profile changes affected antibody binding to a cell surface receptor. Precise and rational modification of N-glycosylation will allow new recombinant protein therapeutics with tailored in vitro and in vivo effects for various biotechnological and biomedical applications.
Subject(s)
Antibodies, Monoclonal/biosynthesis , Cell Engineering , Small Molecule Libraries/pharmacology , Animals , Antibodies, Monoclonal/chemistry , CHO Cells , Cricetulus , Glycosylation/drug effects , Small Molecule Libraries/chemistryABSTRACT
Bacterial biofilms play a critical role in environmental processes, water treatment, human health, and food processing. They exhibit highly complex dynamics due to the interactions between the bacteria and the extracellular polymeric substance (EPS), water, and nutrients and minerals that make up the biofilm. We present a hybrid computational model in which the dynamics of discrete bacterial cells are simulated within a multiphase continuum, consisting of EPS and water as separate interacting phases, through which nutrients and minerals diffuse. Bacterial cells in our model consume water and nutrients in order to grow, divide, and produce EPS. Consequently, EPS flows outward from the bacterial colony, while water flows inward. The model predicts bacterial colony formation as a treelike structure. The distribution of bacterial growth and EPS production is found to be sensitive to the pore spacing between bacteria and the consumption of nutrients within the bacterial colony. Forces that are sometimes neglected in biofilm simulations, such as lubrication force between nearby bacterial cells and osmotic (swelling) pressure force resulting from gradients in EPS concentration, are observed to have an important effect on biofilm growth via their influence on bacteria pore spacing and associated water/nutrient percolation into the bacterial colony.
Subject(s)
Biofilms/growth & development , Models, Biological , Bacteria/growth & development , Bacteria/metabolism , Biomechanical Phenomena , Computational Biology , Computer Simulation , Elastic Modulus , Extracellular Polymeric Substance Matrix/metabolism , Humans , Imaging, Three-Dimensional , Mathematical Concepts , Systems Biology , Viscosity , Water/metabolismABSTRACT
BACKGROUND: The National Cardiogenic Shock Initiative is a single-arm, prospective, multicenter study to assess outcomes associated with early mechanical circulatory support (MCS) in patients presenting with acute myocardial infarction and cardiogenic shock (AMICS) treated with percutaneous coronary intervention (PCI). METHODS: Between July 2016 and February 2019, 35 sites participated and enrolled into the study. All centers agreed to treat patients with AMICS using a standard protocol emphasizing invasive hemodynamic monitoring and rapid initiation of MCS. Inclusion and exclusion criteria mimicked those of the "SHOCK" trial with an additional exclusion criteria of intra-aortic balloon pump counter-pulsation prior to MCS. RESULTS: A total of 171 consecutive patients were enrolled. Patients had an average age of 63 years, 77% were male, and 68% were admitted with AMICS. About 83% of patients were on vasopressors or inotropes, 20% had a witnessed out of hospital cardiac arrest, 29% had in-hospital cardiac arrest, and 10% were under active cardiopulmonary resuscitation during MCS implantation. In accordance with the protocol, 74% of patients had MCS implanted prior to PCI. Right heart catheterization was performed in 92%. About 78% of patients presented with ST-elevation myocardial infarction with average door to support times of 85 ± 63 min and door to balloon times of 87 ± 58 min. Survival to discharge was 72%. Creatinine ≥2, lactate >4, cardiac power output (CPO) <0.6 W, and age ≥ 70 years were predictors of mortality. Lactate and CPO measurements at 12-24 hr reliably predicted overall mortality postindex procedure. CONCLUSION: In contemporary practice, use of a shock protocol emphasizing best practices is associated with improved outcomes.
Subject(s)
Clinical Protocols , Heart-Assist Devices , Non-ST Elevated Myocardial Infarction/therapy , Percutaneous Coronary Intervention , ST Elevation Myocardial Infarction/therapy , Shock, Cardiogenic/therapy , Aged , Female , Hemodynamics , Humans , Male , Middle Aged , Non-ST Elevated Myocardial Infarction/diagnosis , Non-ST Elevated Myocardial Infarction/mortality , Non-ST Elevated Myocardial Infarction/physiopathology , Percutaneous Coronary Intervention/adverse effects , Percutaneous Coronary Intervention/mortality , Prospective Studies , Prosthesis Design , Recovery of Function , Risk Factors , ST Elevation Myocardial Infarction/diagnosis , ST Elevation Myocardial Infarction/mortality , ST Elevation Myocardial Infarction/physiopathology , Shock, Cardiogenic/diagnosis , Shock, Cardiogenic/mortality , Shock, Cardiogenic/physiopathology , Time Factors , Treatment Outcome , United StatesABSTRACT
Analysis of microRNA (miR) expression in the central nervous system white matter of SJL mice infected with the BeAn strain of Theiler's murine encephalomyelitis virus (TMEV) revealed a significant reduction of miR-219, a critical regulator of myelin assembly and repair. Restoration of miR-219 expression by intranasal administration of a synthetic miR-219 mimic before disease onset ameliorates clinical disease, reduces neurogliosis, and partially recovers motor and sensorimotor function by negatively regulating proinflammatory cytokines and virus RNA replication. Moreover, RNA sequencing of host lesions showed that miR-219 significantly downregulated two genes essential for the biosynthetic cholesterol pathway, Cyp51 (lanosterol 14-α-demethylase) and Srebf1 (sterol regulatory element-binding protein-1), and reduced cholesterol biosynthesis in infected mice and rat CG-4 glial precursor cells in culture. The change in cholesterol biosynthesis had both anti-inflammatory and anti-viral effects. Because RNA viruses hijack endoplasmic reticulum double-layered membranes to provide a platform for RNA virus replication and are dependent on endogenous pools of cholesterol, miR-219 interference with cholesterol biosynthesis interfered virus RNA replication. These findings demonstrate that miR-219 inhibits TMEV-induced demyelinating disease through its anti-inflammatory and anti-viral properties.
Subject(s)
Cardiovirus Infections/complications , Cardiovirus Infections/virology , Demyelinating Diseases/etiology , Demyelinating Diseases/pathology , MicroRNAs/genetics , Theilovirus , Viral Load , Animals , Biomarkers , Cell Line , Cholesterol/metabolism , Cytokines/metabolism , Demyelinating Diseases/metabolism , Disease Models, Animal , Female , Fibrinogen/metabolism , Gene Expression Regulation , Inflammation Mediators/metabolism , Lipid Metabolism/genetics , Mice , Microglia/metabolism , RNA Interference , RatsABSTRACT
We report a global adeno-associated virus (AAV)9-based gene therapy protocol to deliver therapeutic galactosylceramidase (GALC), a lysosomal enzyme that is deficient in Krabbe's disease. When globally administered via intrathecal, intracranial, and intravenous injections to newborn mice affected with GALC deficiency (twitcher mice), this approach largely surpassed prior published benchmarks of survival and metabolic correction, showing long-term protection of demyelination, neuroinflammation, and motor function. Bone marrow transplantation, performed in this protocol without immunosuppressive preconditioning, added minimal benefits to the AAV9 gene therapy. Contrasting with other proposed pre-clinical therapies, these results demonstrate that achieving nearly complete correction of GALC's metabolic deficiencies across the entire nervous system via gene therapy can have a significant improvement to behavioral deficits, pathophysiological changes, and survival. These results are an important consideration for determining the safest and most effective manner for adapting gene therapy to treat this leukodystrophy in the clinic.
Subject(s)
Carbohydrate Metabolism , Galactosylceramidase/genetics , Galactosylceramidase/metabolism , Genetic Therapy , Leukodystrophy, Globoid Cell/genetics , Leukodystrophy, Globoid Cell/metabolism , Phenotype , Animals , Autonomic Pathways/metabolism , Autonomic Pathways/pathology , Autonomic Pathways/ultrastructure , Axons/metabolism , Axons/pathology , Axons/ultrastructure , Behavior, Animal , Brain/metabolism , Dependovirus/genetics , Disease Models, Animal , Female , Gene Expression , Genetic Vectors/administration & dosage , Genetic Vectors/genetics , Genetic Vectors/pharmacokinetics , Leukodystrophy, Globoid Cell/diagnosis , Leukodystrophy, Globoid Cell/therapy , Male , Mice , Myelin Sheath/metabolism , Myelin Sheath/pathology , Myelin Sheath/ultrastructure , Tissue Distribution , Transduction, Genetic , Treatment OutcomeABSTRACT
Pulmonary hypertension describes a heterogeneous disease defined by increased pulmonary artery pressures, and progressive increase in pulmonary vascular resistance due to pathologic remodeling of the pulmonary vasculature involving pulmonary endothelial cells, pericytes, and smooth muscle cells. This process occurs under various conditions, and although these populations vary, the clinical manifestations are the same: progressive dyspnea, increases in right ventricular (RV) afterload and dysfunction, RV-pulmonary artery uncoupling, and right-sided heart failure with systemic circulatory collapse. The overall estimated 5-yr survival rate is 72% in highly functioning patients, and as low as 28% for those presenting with advanced symptoms. Metabolic theories have been suggested as underlying the pathogenesis of pulmonary hypertension with growing evidence of the role of mitochondrial dysfunction involving the major proteins of the electron transport chain, redox-related enzymes, regulators of the proton gradient and calcium homeostasis, regulators of apoptosis, and mitophagy. There remain more studies needed to characterize mitochondrial dysfunction leading to impaired vascular relaxation, increase proliferation, and failure of regulatory mechanisms. The effects on endothelial cells and resulting interactions with their microenvironment remain uncharted territory for future discovery. Additionally, on the basis of observations that the "plexigenic lesions" of pulmonary hypertension resemble the unregulated proliferation of tumor cells, similarities between cancer pathobiology and pulmonary hypertension have been drawn, suggesting interactions between mitochondria and angiogenesis. Recently, mitochondria targeting has become feasible, which may yield new therapeutic strategies. We present a state-of-the-art review of the role of mitochondria in both the pathobiology of pulmonary hypertension and potential therapeutic targets in pulmonary vascular processes.
Subject(s)
Hypertension, Pulmonary/etiology , Hypertension, Pulmonary/pathology , Mitochondria/pathology , Mitochondrial Diseases/complications , Animals , HumansABSTRACT
An experimental study has been performed to measure the effect of ultrasound on nanoparticle diffusion in an agarose hydrogel. Agarose hydrogel is often used as a simulant for biofilms and certain biological tissues, such as muscle and brain tissue. The work was motivated by recent experiments indicating that ultrasonic excitation of moderate intensity can significantly enhance nanoparticle diffusion in a hydrogel. The objective of the current study was to obtain detailed measurements of the effect of ultrasound on nanoparticle diffusion in comparison to the molecular diffusion in the absence of acoustic excitation. Experiments were conducted with 1 MHz ultrasound waves and nanoparticle diameters of 20 and 100 nm, using fluorescent imaging to measure particle concentration distribution. Under ultrasound exposure, the experiments yield estimates for both acoustic diffusion coefficients as well as acoustic streaming velocity within the hydrogel. Measured values of acoustic streaming velocity were on the order of 0.1 µm/s, which agree well with a theoretical estimate. Measured values of the acoustic diffusion coefficient were found to be 74% larger than the molecular diffusion coefficient of the nanoparticles for 20 nm particles and 133% larger than the molecular diffusion coefficient for 100 nm particles.
ABSTRACT
BACKGROUND: The prevalence of opioid use disorder (OUD) has increased sharply. Office-based opioid treatment with buprenorphine (OBOT) is effective but often underutilized because of physicians' lack of experience prescribing this therapy. Little is known about US residency training programs' provision of OBOT and addiction medicine training. METHODS: The authors conducted a survey of residency program directors (RPDs) at all US residency programs in internal medicine, family medicine, and psychiatry to assess the frequency with which their residents provide care for OUD, presence and features of curricula in OBOT and addiction medicine, RPDs' beliefs about OBOT, and potential barriers to providing OBOT training. RESULTS: The response rate was 49.5% (476 of 962). Although 76.9% of RPDs reported that residents frequently manage patients with OUD, only 23.5% reported that their program dedicates 12 or more hours of curricular time to addiction medicine, 35.9% reported that their program encourages/requires training in OBOT, and 22.6% reported that their program encourages/requires obtaining a Drug Enforcement Administration (DEA) waiver to prescribe buprenorphine. Most RPDs believe that OBOT is an important treatment option for OUD (88.1%) and that increased residency training in OBOT would improve access to OBOT (73.7%). The authors also found that programs whose RPD had favorable views of OBOT were more likely to provide OBOT and addiction medicine training. Psychiatry programs were most likely to provide OBOT training and their RPDs most likely to have beliefs about OBOT that were positive. Commonly cited barriers to implementing OBOT training include a lack of waivered preceptors (76.9%), competing curricular priorities (64.1%), and a lack of support (social work and counseling) services (54.0%). CONCLUSIONS: Internal medicine, family medicine, and psychiatry residents often care for patients with OUD, and most RPDs believe that increased residency training in OBOT would increase access to this treatment. Yet, only a minority of programs offer training in OBOT.
Subject(s)
Addiction Medicine/education , Ambulatory Care , Curriculum , Internship and Residency , Opiate Substitution Treatment , Opioid-Related Disorders , Analgesics, Opioid/therapeutic use , Buprenorphine/therapeutic use , Family Practice/education , Health Knowledge, Attitudes, Practice , Humans , Internal Medicine/education , Opioid-Related Disorders/drug therapy , Psychiatry/education , Surveys and Questionnaires , United StatesABSTRACT
A stochastic model is presented for nanoparticle transport in a biofilm to explain how the combination of acoustic oscillations and intermittent retention due to interaction with the pore walls of the biofilm leads to diffusion enhancement. An expression for the effective diffusion coefficient was derived that varies with the square of the oscillation velocity amplitude. This expression was validated by comparison of an analytical diffusion solution to the stochastic model prediction. The stochastic model was applied to an example problem associated with liposome penetration into a hydrogel, and it was found to yield solutions in which liposome concentration varied exponentially with distance into the biofilm.
Subject(s)
Bacteria/radiation effects , Biofilms/radiation effects , Models, Biological , Nanoparticles/chemistry , Ultrasonic Waves , Ultrasonics/methods , Bacteria/growth & development , Bacteria/metabolism , Biofilms/growth & development , Diffusion , Motion , Nanoparticles/metabolism , Porosity , Stochastic Processes , Time FactorsABSTRACT
Because biofilms have resistance to antibiotics, their control using minimum amounts of chemicals and energy becomes a critical issue particularly for resource-constrained long-term space and deep-sea explorations. This preliminary study investigates how ultrasound promoting penetration of antibiotic-loaded liposomes into alginate-based bacterial biofilms, resulting in enhanced bacterial (Ralstonia insidiosa) killing. Nano-sized liposomes are used as a delivery vehicle for the antibiotic gentamicin. Alginate-based synthetic biofilms, which are widely acknowledged as biofilm phantoms, filled with liposome solution are formed at the bottoms of six-well Petri dishes and exposed to ultrasound (frequency = 2.25 MHz, 10% duty cycle, and spatially and temporally averaged intensity ISAPA = 4.4 W/cm(2)). Gentamicin is released from liposomes after they are lysed using detergent solution (0.05% sodium dodecyl sulfate, 1.0% Triton X-100) and incubated for 20 min. The alginate biofilm is dissolved and diluted, counting of colony-forming units shows about 80% of the bacteria are killed. It has also been shown the liposome-capture density by the alginate film increases linearly with the ultrasound intensity up to ISAPA = 6.2 W/cm(2) reaching approximately threefold that without ultrasound. Measurement by using particle-image velocimetry has demonstrated the acoustic streaming with modification by thermal convection controls the enhancement of the liposome capture rate.
Subject(s)
Anti-Bacterial Agents/administration & dosage , Biofilms , Disinfection/methods , Gentamicins/administration & dosage , Liposomes , Ultrasonic Waves , Water Purification/methods , Alginates , Bacterial Load , Drug Carriers , Fluorescein-5-isothiocyanate/analysis , Glucuronic Acid , Hexuronic Acids , Hot Temperature , Hydrogels , Laser-Doppler Flowmetry , Ralstonia/drug effectsABSTRACT
The Cooling to Help Injured Lungs (CHILL) trial is an open label, two group, parallel design multicenter, randomized phase IIB clinical trial assessing the efficacy and safety of targeted temperature management with combined external cooling and neuromuscular blockade to block shivering in patients with early moderate-severe acute respiratory distress syndrome (ARDS). This report provides the background and rationale for the clinical trial and outlines the methods using the Consolidated Standards of Reporting Trials guidelines. Key design challenges include: [1] protocolizing important co-interventions; [2] incorporation of patients with COVID-19 as the cause of ARDS; [3] inability to blind the investigators; and [4] ability to obtain timely informed consent from patients or legally authorized representatives early in the disease process. Results of the Reevaluation of Systemic Early Neuromuscular Blockade (ROSE) trial informed the decision to mandate sedation and neuromuscular blockade only in the group assigned to therapeutic hypothermia and proceed without this mandate in the control group assigned to a usual temperature management protocol. Previous trials conducted in National Heart, Lung, and Blood Institute ARDS Clinical Trials (ARDSNet) and Prevention and Early Treatment of Acute Lung Injury (PETAL) Networks informed ventilator management, ventilation liberation and fluid management protocols. Since ARDS due to COVID-19 is a common cause of ARDS during pandemic surges and shares many features with ARDS from other causes, patients with ARDS due to COVID-19 are included. Finally, a stepwise approach to obtaining informed consent prior to documenting critical hypoxemia was adopted to facilitate enrollment and reduce the number of candidates excluded because eligibility time window expiration.
ABSTRACT
Patients with mutations in HOIL1 experience a complex immune disorder including intestinal inflammation. To investigate the role of HOIL1 in regulating intestinal inflammation, we employed a mouse model of partial HOIL1 deficiency. The ileum of HOIL1-deficient mice displayed features of type 2 inflammation including tuft cell and goblet cell hyperplasia, and elevated expression of Il13, Il5 and Il25 mRNA. Inflammation persisted in the absence of T and B cells, and bone marrow chimeric mice revealed a requirement for HOIL1 expression in radiation-resistant cells to regulate inflammation. Although disruption of IL-4 receptor alpha (IL4Rα) signaling on intestinal epithelial cells ameliorated tuft and goblet cell hyperplasia, expression of Il5 and Il13 mRNA remained elevated. KLRG1hi CD90lo group 2 innate lymphoid cells were increased independent of IL4Rα signaling, tuft cell hyperplasia and IL-25 induction. Antibiotic treatment dampened intestinal inflammation indicating commensal microbes as a contributing factor. We have identified a key role for HOIL1, a component of the Linear Ubiquitin Chain Assembly Complex, in regulating type 2 inflammation in the small intestine. Understanding the mechanism by which HOIL1 regulates type 2 inflammation will advance our understanding of intestinal homeostasis and inflammatory disorders and may lead to the identification of new targets for treatment.
Subject(s)
Immunity, Innate , Interleukin-13 , Ubiquitin-Protein Ligases/metabolism , Animals , Hyperplasia , Inflammation , Interleukin-5 , Intestine, Small , Lymphocytes , Mice , RNA, MessengerABSTRACT
Base editors are fusions of a deaminase and CRISPR-Cas ribonucleoprotein that allow programmable installment of transition mutations without double-strand DNA break intermediates. The breadth of potential base editing targets is frequently limited by the requirement of a suitably positioned Cas9 protospacer adjacent motif. To address this, we used structures of Cas9 and TadA to design a set of inlaid base editors (IBEs), in which deaminase domains are internal to Cas9. Several of these IBEs exhibit shifted editing windows and greater editing efficiency, enabling editing of targets outside the canonical editing window with reduced DNA and RNA off-target editing frequency. Finally, we show that IBEs enable conversion of the pathogenic sickle cell hemoglobin allele to the naturally occurring HbG-Makassar variant in patient-derived hematopoietic stem cells.
Subject(s)
Anemia, Sickle Cell/genetics , Anemia, Sickle Cell/therapy , Gene Editing , Mutation , CRISPR-Associated Protein 9 , CRISPR-Cas Systems , Clustered Regularly Interspaced Short Palindromic Repeats , DNA , DNA Breaks, Double-Stranded , HEK293 Cells , High-Throughput Nucleotide Sequencing , Humans , RNAABSTRACT
Site specific integration (SSI) expression systems offer robust means of generating highly productive and stable cell lines for traditional monoclonal antibodies. As complex modalities such as antibody-like molecules comprised of greater than two peptides become more prevalent, greater emphasis needs to be placed on the ability to produce appreciable quantities of the correct product of interest (POI). The ability to screen several transcript stoichiometries could play a large role in ensuring high amounts of the correct POI. Here we illustrate implementation of an SSI expression system with a single site of integration for development and production of a multi-chain, bi-specific molecule. A SSI vector with a single copy of all of the genes of interest was initially selected for stable Chinese hamster ovary transfection. While the resulting transfection pools generated low levels of the desired heterodimer, utilizing an intensive clone screen strategy, we were able to identify clones having significantly higher levels of POI. In-depth genotypic characterization of clones having the desirable phenotype revealed that a duplication of the light chain within the landing pad was responsible for producing the intended molecule. Retrospective transfection pool analysis using a vector configuration mimicking the transgene configuration found in the clones, as well as other vector configurations, yielded more favorable results with respect to % POI. Overall, the study demonstrated that despite the theoretical static nature of the SSI expression system, enough heterogeneity existed to yield clones having significantly different transgene phenotypes/genotypes and support production of a complex multi-chain molecule.
Subject(s)
Cricetulus , Animals , CHO Cells , Cricetinae , Recombinant Proteins/genetics , Retrospective Studies , Transfection , TransgenesABSTRACT
Interactions in quantum systems can spread initially localized quantum information into the exponentially many degrees of freedom of the entire system. Understanding this process, known as quantum scrambling, is key to resolving several open questions in physics. Here, by measuring the time-dependent evolution and fluctuation of out-of-time-order correlators, we experimentally investigate the dynamics of quantum scrambling on a 53-qubit quantum processor. We engineer quantum circuits that distinguish operator spreading and operator entanglement and experimentally observe their respective signatures. We show that whereas operator spreading is captured by an efficient classical model, operator entanglement in idealized circuits requires exponentially scaled computational resources to simulate. These results open the path to studying complex and practically relevant physical observables with near-term quantum processors.
ABSTRACT
Gram-negative bacteria, as well as some Gram-positive bacteria, possess hair-like appendages known as fimbriae, which play an important role in adhesion of the bacteria to surfaces or to other bacteria. Unlike the sex pili or flagellum, the fimbriae are quite numerous, with of order 1000 fimbriae appendages per bacterial cell. In this paper, a recently developed hybrid model for bacterial biofilms is used to examine the role of fimbriae tension force on the mechanics of bacterial biofilms. Each bacterial cell is represented in this model by a spherocylindrical particle, which interact with each other through collision, adhesion, lubrication force, and fimbrial force. The bacterial cells absorb water and nutrients and produce extracellular polymeric substance (EPS). The flow of water and EPS, and nutrient diffusion within these substances, is computed using a continuum model that accounts for important effects such as osmotic pressure gradient, drag force on the bacterial cells, and viscous shear. The fimbrial force is modeled using an outer spherocylinder capsule around each cell, which can transmit tensile forces to neighboring cells with which the fimbriae capsule collides. We find that the biofilm structure during the growth process is dominated by a balance between outward drag force on the cells due to the EPS flow away from the bacterial colony and the inward tensile fimbrial force acting on chains of cells connected by adhesive fimbriae appendages. The fimbrial force also introduces a large rotational motion of the cells and disrupts cell alignment caused by viscous torque imposed by the EPS flow. The current paper characterizes the competing effects of EPS drag and fimbrial force using a series of computations with different values of the ratio of EPS to bacterial cell production rate and different numbers of fimbriae per cell.