Multifunctional Dopamine-Based Hydrogel Microneedle Electrode for Continuous Ketone Sensing.

Diabetic ketoacidosis (DKA), a severe complication of type 1 diabetes (T1D), is triggered by production of large quantities of ketone bodies, requiring patients with T1D to constantly monitor their ketone levels. Here, a skin-compatible hydrogel microneedle (HMN)-continuous ketone monitoring (HMN-CKM) device is reported. The sensing mechanism relies on the catechol-quinone chemistry inherent to the dopamine (DA) molecules that are covalently linked to the polymer structure of the HMN patch. The DA serves the dual-purpose of acting as a redox mediator for measuring the byproduct of oxidation of 3-beta-hydroxybutyrate (ß-HB), the primary ketone bodies; while, also facilitating the formation of a crosslinked HMN patch. A universal approach involving pre-oxidation and detection of the generated catechol compounds is introduced to correlate the sensor response to the ß-HB concentrations. It is further shown that real-time tracking of a decrease in ketone levels of T1D rat model is possible using the HMN-CKM device, in conjunction with a data-driven machine learning model that considers potential time delays.

Performance evaluation of a novel artificial intelligence (AI)-assisted digital microscopy system for the routine analysis of bone marrow aspirates.

Bone marrow aspiration (BMA) smear analysis is essential for diagnosis, treatment and monitoring of a variety of benign and neoplastic hematological conditions. Currently this analysis is performed by manual microscopy. We conducted a multi-center study to validate a computational microscopy approach with an artificial intelligence (AI)-driven decision support system. A total of 795 BMA specimens (615 Romanowsky-stained and 180 Prussian blue-stained) from patients with neoplastic and other clinical conditions were analyzed, comparing the performance of the Scopio Labs X100 Full Field BMA system (test method) with manual microscopy (reference method). The system provided an average of 1385±536 (range 0-3131) cells per specimen for analysis. An average of 39.98±19.64 fields of view (range 0-140) per specimen were selected by the system for analysis, of them 87±21% (range 0-100%) were accepted by the qualified operators. These regions were included in an average of 17.62±7.24 regions of interest (range 1-50) per specimen. The efficiency, sensitivity, and specificity for primary and secondary marrow aspirate characteristics (maturation, morphology, and count assessment), as well as overall inter-user agreement, were evaluated. The test method showed high correlation with the reference method for comprehensive BMA evaluation, both on Romanowsky (90.85% efficiency, 81.61% sensitivity; specificity 92.88%) and Prussian blue (90.0% efficiency, 81.94% sensitivity; 93.38% specificity) stained samples. The overall agreement between the test and reference method for BMA assessment was 91.1%. For repeatability and reproducibility, all standard deviations and coefficients of variation values were below the pre-defined acceptance criteria both for discrete measurements (CV below 20%) and for differential measurements (SD below 5%). The high degree of correlation between the digital decision support system and manual microscopy demonstrates the potential of this system to provide a high-quality, accurate digital BMA analysis, -expediting expert review and diagnosis of BMA specimens, with practical applications including remote BMA evaluation, and possibly new opportunities for the research of normal and neoplastic hematopoiesis.

Continuous pH monitoring using a sensor for the early detection of anastomotic leaks.

Anastomotic leaks (AL) and staple line leaks are a serious post-operative complication that can develop following bariatric surgery. The delay in the onset of symptoms following a leak usually results in reactive diagnostics and treatment, leading to increased patient morbidity and mortality, and a clinical and economic burden on both the patient and the hospital. Despite support in literature for pH as a biomarker for early detection of AL, the current methods of pH detection require significant clinician involvement and resources. Presented here is a polyaniline (PANI)-based pH sensor that can be connected inline to surgical drains to continuously monitor peritoneal secretion in real time for homeostatic changes in pH. During this study, the baseline peritoneal fluid pH was measured in two pigs using the PANI sensor and verified using a benchtop pH probe. The PANI sensor was then utilized to continuously monitor the changes in the pH of peritoneal effluent, as a gastric leak was simulated. The inline sensors were able to detect the resulting local changes in drainage pH within 10 min of leak induction. The successful implementation of this sensor in clinical practice can both enable high efficiency continuous monitoring of patient status and drastically decrease the time required to detect AL, thus potentially decreasing the clinical and economic burden incurred by gastric leaks.

Tunable [3+2] and [4+2] annulations for pyrrolidine and piperidine synthesis.

N-heterocycles are privileged pharmaceutical scaffolds in drug discovery and development. We disclose here divergent intermolecular coupling strategies that can access diverse N-heterocycles directly from olefins. The radical-to-polar mechanistic switching is key for the divergent cyclization processes. These distinctive annulations result in the coupling of alkenes with simple bifunctional reagents for divergent N-heterocycle syntheses.

Intravitreal Triamcinolone Acetonide Presents a Diagnostic Challenge on Noncontrast Computed Tomography.

Triamcinolone acetonide (TA) is a widely used corticosteroid for various ophthalmological indications. We report a case of a 27-year-old female presented with upper eyelid edema and punctate corneal erosions and haze of the left eye, 1 week after pars plana vitrectomy with silicone oil (SO) tamponade and intravitreal TA for diabetic tractional retinal detachment. The condition persisted despite topical and systemic therapy. Computed tomography (CT) scan of the orbits was obtained to exclude postoperative SO migration. The scan showed a hyperintense lesion in the vitreous cavity of the left eye with no SO migration. The radiographic appearance of the lesion mimicked a foreign body; however, history and recent operative note excluded this possibility. A CT scan of various TA preparations revealed that the lesion's density is similar to those of TA. Improvement of corneal haze confirmed that the lesion was consistent with intravitreal TA. The patient developed eyelid edema of the right eye and later was diagnosed with nephrotic syndrome after further investigation. In conclusion, it is important to be familiar with the radiographic appearance of TA on CT to avoid incorrect diagnosis.

Visible light bromide catalysis for oxazoline, pyrrolidine, and dihydrooxazine syntheses via Csp3-H functionalizations.

A catalytic benzylic Csp3-H functionalization protocol is described here. This visible light-mediated process is centered on the utilization of a bromide catalyst and oxidant to generate a nitrogen (N)-centered radical for a site-selective hydrogen atom transfer (HAT) process. This strategy enabled the unconventional syntheses of a number of N-heterocycles dependent on the amide identity. We also discovered a nucleophilicity-dependent kinetic resolution for stereochemical differentiation of Csp3-H bonds that enabled the stereoselective synthesis of cis- and trans-oxazolines.

Systematic Phenotyping and Characterization of the 3xTg-AD Mouse Model of Alzheimer's Disease.

Animal models of disease are valuable resources for investigating pathogenic mechanisms and potential therapeutic interventions. However, for complex disorders such as Alzheimer's disease (AD), the generation and availability of innumerous distinct animal models present unique challenges to AD researchers and hinder the success of useful therapies. Here, we conducted an in-depth analysis of the 3xTg-AD mouse model of AD across its lifespan to better inform the field of the various pathologies that appear at specific ages, and comment on drift that has occurred in the development of pathology in this line since its development 20 years ago. This modern characterization of the 3xTg-AD model includes an assessment of impairments in long-term potentiation followed by quantification of amyloid beta (Aß) plaque burden and neurofibrillary tau tangles, biochemical levels of Aß and tau protein, and neuropathological markers such as gliosis and accumulation of dystrophic neurites. We also present a novel comparison of the 3xTg-AD model with the 5xFAD model using the same deep-phenotyping characterization pipeline and show plasma NfL is strongly driven by plaque burden. The results from these analyses are freely available via the AD Knowledge Portal (https://modeladexplorer.org/). Our work demonstrates the utility of a characterization pipeline that generates robust and standardized information relevant to investigating and comparing disease etiologies of current and future models of AD.

I spy without my eye: Covert attention in human social interactions.

Looking at other people allows us to collect information about them, but it can also reveal our attentional state when we would rather conceal it. We report that individuals spontaneously employ sustained covert monitoring, rather than direct looking, when evaluating the actions of a live stranger. In contrast, individuals look directly at the actions of a stranger on video. We argue that the ability to secretly monitor live others without executing a look towards them is an important process that compensates for the risk of looking directly during certain social situations. Covert monitoring allows people to avoid visually communicating to others that they are the focus of one's attention. This represents a previously undocumented function of covert attention outside of the laboratory. It suggests that the relationship between covert attention and looking is dynamic and likely to be foundational to the successful navigation of real-world social situations.

Modified hydrodissection to prevent intraoperative iris prolapse.

A modified hydrodissection technique to prevent intraoperative iris prolapse is presented. The phacoemulsification tip is inserted into the main ocular incision while hydrodissection is performed through a side-port incision. Placement of the phacoemulsification tip in this location prevents iris prolapse. This technique can be used routinely and might be especially applicable in cases with a high risk for iris prolapse, such as in intraoperative floppy-iris syndrome.

Improved exercise capacity in cyclophilin-D knockout mice associated with enhanced oxygen utilization efficiency and augmented glucose uptake via AMPK-TBC1D1 signaling nexus.

We previously reported in HEK 293T cells that silencing the mitochondrial peptidyl prolyl isomerase cyclophilin-D (Cyp-D) reduces Vo2. We now report that in vivo Cyp-D ablation using constitutive Cyp-D knockout (KO) mice also reduces Vo2 both at rest (∼15%) and during treadmill exercise (∼12%). Yet, despite Vo2 reduction, these Cyp-D KO mice ran longer (1071 ± 77 vs. 785 ± 79 m; P = 0.002), for longer time (43 ± 3 vs. 34 ± 3 min; P = 0.004), and at higher speed (34 ± 1 vs. 29 ± 1 m/s; P ≤ 0.001), resulting in increased work (87 ± 6 vs. 58 ± 6 J; P ≤ 0.001). There were parallel reductions in carbon dioxide production, but of lesser magnitude, yielding a 2.3% increase in the respiratory exchange ratio consistent with increased glucose utilization as respiratory substrate. In addition, primary skeletal muscle cells of Cyp-D KO mice subjected to electrical stimulation exhibited higher glucose uptake (4.4 ± 0.55 vs. 2.6 ± 0.04 pmol/mg/min; P ≤ 0.001) with enhanced AMPK activation (0.58 ± 0.06 vs. 0.38 ± 0.03 pAMPK/ß-tubulin ratio; P ≤ 0.01) and TBC1 (Tre-2/USP6, BUB2, Cdc16) domain family, member 1 (TBC1D1) inactivation. Likewise, pharmacological activation of AMPK also increased glucose uptake (3.2 ± 0.3 vs. 2.3 ± 0.2 pmol/mg/min; P ≤ 0.001). Moreover, lactate and ATP levels were increased in these cells. Taken together, Cyp-D ablation triggered an adaptive response resulting in increased exercise capacity despite less oxygen utilization associated with increased glucose uptake and utilization involving AMPK-TBC1D1 signaling nexus.-Radhakrishnan, J., Baetiong, A., Kaufman, H., Huynh, M., Leschinsky, A., Fresquez, A., White, C., DiMario, J. X., Gazmuri, R. J. Improved exercise capacity in cyclophilin-D knockout mice associated with enhanced oxygen utilization efficiency and augmented glucose uptake via AMPK-TBC1D1 signaling nexus.

Charged residues on the side of the nucleosome contribute to normal Spt16-gene interactions in budding yeast.

Previous work in Saccharomyces cerevisiae identified three residues located in close proximity to each other on the side of the nucleosome whose integrity is required for proper association of the Spt16 component of the FACT complex across transcribed genes. In an effort to gain further insights into the parameters that control Spt16 interactions with genes in vivo, we tested the effects of additional histone mutants on Spt16 occupancy across two constitutively transcribed genes. These studies revealed that mutations in several charged residues in the vicinity of the three residues originally identified as important for Spt16-gene interactions also significantly perturb normal association of Spt16 across genes. Based on these and our previous findings, we propose that the charge landscape across the region encompassed by these residues, which we refer to as the Influences Spt16-Gene Interactions or ISGI region, is an important contributor to proper Spt16-gene interactions in vivo.

Light-responsive nanoparticle depot to control release of a small molecule angiogenesis inhibitor in the posterior segment of the eye.

Therapies for macular degeneration and diabetic retinopathy require intravitreal injections every 4-8 weeks. Injections are uncomfortable, time-consuming, and carry risks of infection and retinal damage. However, drug delivery via noninvasive methods to the posterior segment of the eye has been a major challenge due to the eye's unique anatomy and physiology. Here we present a novel nanoparticle depot platform for on-demand drug delivery using a far ultraviolet (UV) light-degradable polymer, which allows noninvasively triggered drug release using brief, low-power light exposure. Nanoparticles stably retain encapsulated molecules in the vitreous, and can release cargo in response to UV exposure up to 30 weeks post-injection. Light-triggered release of nintedanib (BIBF 1120), a small molecule angiogenesis inhibitor, 10 weeks post-injection suppresses choroidal neovascularization (CNV) in rats. Light-sensitive nanoparticles are biocompatible and cause no adverse effects on the eye as assessed by electroretinograms (ERG), corneal and retinal tomography, and histology.

Improving the inter-laboratory harmonization of the international normalized ratio (INR): utilizing the concept of transference to estimate and/or validate international sensitivity index (ISI) and mean normal prothrombin time (MNPT) values and/or to eliminate measurement bias.

BACKGROUND: The Prothrombin Time (PT) assay is clinically the most often requested coagulation test, as used primarily for monitoring of Vitamin K antagonist therapy where results are typically expressed as an International Normalized Ratio (INR). The INR reflects the patient's PT adjusted for the specific test reagent and instrument combination used by applying two correction factors, namely the International Sensitivity Index (ISI) and the Mean Normal Prothrombin Time (MNPT), according to the formula: INR = (patient PT/MNPT)ISI. When the manufacturer provides an ISI, laboratories are encumbered to check or locally validate the assigned value. Where a manufacturer does not provide an ISI, the laboratory needs to define its own (local ISI) value. The MNPT typically has to be locally defined, based on the population being tested. The main current CLSI recommendation for defining ISI values comprises use of commercial reference ('certified') plasma calibration sets, but FDA cleared material is limited, and different results may arise using different products. The MNPT can be defined using a WHO/CLSI recommended procedure requiring 20 normal individuals or with some calibration sets. Overall, there is limited data to validate the performance of these processes in laboratory practice, and ongoing evidence from external quality assurance (proficiency testing) programs indicates continued failure in INR harmonization, suggesting that ISI and MNPT values used by laboratories (and presumably assessed using current recommended processes) continue to be inaccurate. OBJECTIVE: To assess some novel approaches to the laboratory estimation and/or validation of ISI and MNPT values for use in the INR calculation, and including the process of 'transference', normally used to assess the comparability of analytical systems or to transfer reference intervals between comparable systems. RESULTS: We have successfully adapted these comparative procedures, including 'transference', to permit ongoing estimation and/or validation of ISI and MNPT values for use in INR calculations for a range of instrumentation, which has led to improved harmonization of INR values obtained in our pathology network. These processes do not require the use of any normal individual plasmas or calibrator sets and greatly simplifies the INR process. Evidence for validation of the processes used is provided by ongoing satisfactory performance in external quality assurance (proficiency testing).