Publications by authors named "Jonathan Frank"

A systematic study of the impact of film thickness on the properties of thin Bi films is presented. To this end, epitaxial films of high quality have been grown on a Si (111) substrate with thicknesses ranging from 1.9 to 29.

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c-di-GAMP was first identified in bacteria to promote colonization, while mammalian 2'3'-cGAMP is synthesized by cGAS to activate STING for innate immune stimulation. However, 2'3'-cGAMP function beyond innate immunity remains elusive. Here, we report that 2'3'-cGAMP promotes cell migration independent of innate immunity.

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Detection and differentiation of brown fat in humans poses several challenges, as this tissue is sparse and often mixed with white adipose tissue. Non-invasive detection of beige fat represents an even greater challenge as this tissue is structurally and functionally more like white fat than brown fat. Here we used positron emission tomography with F-fluorodeoxyglucose, computed tomography, xenon-enhanced computed tomography, and dynamic contrast-enhanced ultrasound, to non-invasively detect functional and structural changes associated with the browning process of inguinal white fat, induced in mice by chronic stimulation with the β-adrenergic receptor agonist CL-316243.

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The interactions between polymers and the immune system remains poorly controlled. In some instances, the immune system can produce antibodies specific to polymer constituents. Indeed, roughly half of pegloticase patients without immunomodulation develop high titers of anti-PEG antibodies (APA) to the PEG polymers on pegloticase, which then quickly clear the drug from circulation and render the gout treatment ineffective.

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Brown adipose tissue (BAT) is a fat tissue specialized in heat production (non-shivering thermogenesis) and used by mammals to defend core body temperature when exposed to cold. Several studies have shown that during non-shivering thermogenesis the increase in BAT oxygen demand is met by a local and specific increase in tissue's blood flow. While the vasculature of BAT has been extensively studied postmortem in rodents using histology, optical and CT imaging techniques, vasculature changes during stimulation of non-shivering thermogenesis have never been directly detected in vivo.

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Article Synopsis
  • Hemophilia A is a genetic bleeding disorder caused by low levels of coagulation factor VIII (FVIII), traditionally treated with IV FVIII treatments.
  • Recent research shows gene therapy using a vector called adeno-associated virus (AAV) can help, but challenges like cellular stress and immune response limit its effectiveness.
  • In a study with FVIII-deficient mice, researchers found that a specific type of liver cell's structural changes hindered gene transfer, indicating that the absence of proper liver cell function affects the success of this therapy.
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PEGylation is routinely used to extend the systemic circulation of various protein therapeutics and nanomedicines. Nonetheless, mounting evidence is emerging that individuals exposed to select PEGylated therapeutics can develop antibodies specific to PEG, i.e.

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Discovery of novel drug delivery systems to the brain remains a key task for successful treatment of neurodegenerative disorders. Herein, the biodistribution of immunocyte-based carriers, peripheral blood mononuclear cells (PBMCs), and monocyte-derived EVs are investigated in adult rhesus macaques using longitudinal PET/MRI imaging. Cu-labeled drug carriers are introduced via different routes of administration: intraperitoneal (IP), intravenous (IV), or intrathecal (IT) injection.

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Catalytic conversion of alcohols underlies many commodity and fine chemical syntheses, but a complete mechanistic understanding is lacking. We examined catalytic oxidative conversion of methanol near atmospheric pressure using operando small-aperture molecular beam time-of-flight mass spectrometry, interrogating the gas phase 500 μm above Pd-based catalyst surfaces. In addition to a variety of stable C species, we detected methoxymethanol (CHOCHOH)─a rarely observed and reactive C oxygenate that has been proposed to be a critical intermediate in methyl formate production.

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The in vivo fate of nanoformulated drugs is governed by the physicochemical properties of the drug and the functionality of nanocarriers. Nanoformulations such as polymeric micelles, which physically encapsulate poorly soluble drugs, release their payload into the bloodstream during systemic circulation. This results in three distinct fractions of the drug-nanomedicine: encapsulated, protein-bound, and free drug.

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Pegloticase is an enzyme used to reduce serum uric acid levels in patients with chronic, treatment-refractory gout. Clinically, about 40% of patients develop high titers of anti-PEG antibodies (APA) after initial treatment, which in turn quickly eliminate subsequent doses of pegloticase from the systemic circulation and render the treatment ineffective. We previously found that pre-infusion with high MW free PEG (40 kDa) can serve as a decoy to saturate circulating APA, preventing binding to a subsequently administered dose of PEG-liposomes and restoring their prolonged circulation in mice, without any detectible toxicity.

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The study aims to assess site assessment of the performance of F-PBR-111 as a neuroinflammation marker in the cuprizone mouse model of multiple sclerosis (MS). F-PBR-111 PET imaging has not been well evaluated in multiple sclerosis applications both in preclinical and clinical research. This study will help establish the potential utility of F-PBR-111 PET in preclinical MS research and future animal and future human applications.

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Many important chemically reacting systems are inherently multi-dimensional with spatial and temporal variations in the thermochemical state, which can be strongly coupled to interactions with transport processes. Fundamental insights into these systems require multi-dimensional measurements of the thermochemical state as well as fluid dynamics quantities. Laser-based imaging diagnostics provide spatially and temporally resolved measurements that help address this need.

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Background: Brown adipose tissue (BAT) is a fat tissue found in most mammals that helps regulate energy balance and core body temperature through a sympathetic process known as non-shivering thermogenesis. BAT activity is commonly detected and quantified in [F]FDG positron emission tomography/computed tomography (PET/CT) scans, and radiotracer uptake in BAT during adrenergic stimulation is often used as a surrogate measure for identifying thermogenic activity in the tissue. BAT thermogenesis is believed to be contingent upon the expression of the protein UCP1, but conflicting results have been reported in the literature concerning [F]FDG uptake within BAT of mice with and without UCP1.

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Hymenogaster is an ectomycorrhizal genus of brown-spored sequestrate fungi that is related to the mushroom-forming genera Hebeloma and Alnicola (Agaricales). However, because of difficulties in morphological taxonomy of sequestrate fungi, Hymenogaster has become a polyphyletic repository for a variety of unrelated brown-spored sequestrate species. During studies of ectomycorrhizal ecology and sequestrate fungal evolution in the western USA, we encountered specimens of a morphologically unique species.

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This study was performed to compare outcomes of open, arthroscopic, and percutaneous surgical techniques for lateral epicondylitis. We searched PubMed (MEDLINE) for literature published between January 1, 2004 and May 23, 2015 using these key words: lateral epicondylitis AND (surgery OR operative OR surgical OR open OR arthroscopic OR percutaneous). Meta-analyses were performed for outcomes reported in 3 studies using 2-sample and 2-proportion Z-tests.

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Background: The biomechanical effects of lateral meniscal posterior root tears with and without meniscofemoral ligament (MFL) tears in anterior cruciate ligament (ACL)-deficient knees have not been studied in detail.

Purpose: To determine the biomechanical effects of the lateral meniscus (LM) posterior root tear in ACL-intact and ACL-deficient knees. In addition, the biomechanical effects of disrupting the MFLs in ACL-deficient knees with meniscal root tears were evaluated.

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The importance of the acetabular labrum has been well documented for the function and overall health of the hip joint. Several biomechanical studies have shown the sealing effect of the acetabular labrum. In the past decade, labral repair procedures have gained increased attention, with the literature suggesting that the outcomes after hip arthroscopy are directly related to labral preservation.

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Meniscal root tears occur in isolation or concurrently with ligamentous knee injury and cause significantly altered knee mechanics with the loss of normal meniscus hoop stress. This loss of normal meniscus function can result in abnormal knee kinematics and, subsequently, more rapid degenerative changes of the knee articular surface. In the setting of anterior cruciate ligament tear, the posterolateral meniscus root is most commonly damaged.

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Lateral hip pain associated with trochanteric bursitis is a common orthopedic condition, and can be debilitating in chronic or recalcitrant situations. Conservative management is the most common initial treatment and often results in resolution of symptoms and improved patient outcomes. These modalities include rest, activity modification, physical therapy, anti-inflammatory medication, or corticosteroid injections.

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Femoroacetabular impingement (FAI) is an increasingly recognized cause of hip pain. This pathology often involves abnormal femoral neck shape (cam-type FAI), acetabular over coverage (pincer-type FAI), or mixed pathology. Surgical treatment of this entity includes labral repair and femoral head-neck osteochondroplasty.

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Primary synovial chondromatosis is a rare, benign, proliferative disease of hyaline cartilaginous bodies within the synovium of joints. We report a rare case of primary synovial chondromatosis diffusely affecting the ulnohumeral joint causing pain and motion limitations with extrusion into the cubital tunnel and compressing the ulnar nerve but without any preoperative signs or symptoms of ulnar nerve compression. The patient was successfully treated with an open synovectomy to limit disease progression and improve motion.

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Background And Objective: The hypoxia PET tracer, 1-[18F]fluoro-3-(2-nitro-1Himidazol- 1-yl)-propan-2-ol ([18F]FMISO) is the first radiotracer developed for hypoxia PET imaging and has shown promising for cancer diagnosis and prognosis. However, access to [18F]FMISO radiotracer is limited due to the needed cyclotron and radiochemistry expertise. The study aimed to develop the automated production method on the [18F]FMISO radiotracer with the novel fully automated platform of the BG75 system and validate its usage on animal tumor models.

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