SuperMap algorithm: an efficient, safe and accurate modality for mapping and eliminating challenging cardiac arrhythmias.

Even with the development of advanced catheter-based mapping systems, there remain several challenges in the electrophysiological evaluation and elimination of atrial arrhythmias. For instance, atrial tachycardias with irregular rates cannot be reliably mapped by systems that require stability in order to sequentially gather data points to be organized thereafter. Separately, these arrhythmias often arise following initial ablation for atrial fibrillation, posing logistic challenges. Here, we present the available literature summarizing the use of a non-contact mapping catheter, the AcQMap catheter, in conjunction with SuperMap, an algorithm that compiles a large number of non-contact data points from multiple catheter positions within the atria. These studies demonstrate the efficiency, safety and accuracy of this technology.

Irregular heart rhythms (arrhythmias) are often treatable with medications, but sometimes require expert evaluation in a cardiac electrophysiology laboratory. They are often studied and treated using thin, flexible catheters which enter the body through blood vessels in the leg and reach the internal walls of the heart. Time, expertise and specialized equipment are necessary to identify characteristics specific to each patient's arrhythmia. For each arrhythmia, a unique electrical blueprint is created before trying to eliminate it. The fleeting nature of certain arrhythmias can make it difficult to generate these blueprints, and many take a lot of time to accurately identify, leading to procedural challenges. Here we evaluate studies discussing the use of a new catheter (AcQMap) and its accompanying strategy for identifying arrhythmias. Unlike traditional catheters that require direct contact with the internal walls of the heart, the AcQMap catheter floats within these blood-filled chambers and does not touch the walls when obtaining data points. Instead, using ultrasound waves and electrical signals, it can generate data points to create blueprints. This technology also uses a new algorithm that enables the catheter to move freely within the heart, obtaining numerous data points and grouping them together to create maps efficiently and safely, even for fleeting or challenging arrhythmias.

Purulent Bacterial Pericarditis: Rare Yet Lethal.

Bacterial pericarditis is a rare phenomenon that progresses rapidly and carries high mortality. Patients presenting with new pericardial effusions are often evaluated for concomitant rheumatologic, oncologic, and infectious diseases. We present a complex case of purulent pericarditis with pneumopericardium.

Boosting inpatient exercise after hip fracture using an alternative workforce: a mixed methods implementation evaluation.

BACKGROUND: Hip fracture has a devastating impact on individuals and is an increasing burden for health systems and society. Compared to usual care, increased physiotherapy provision has demonstrated efficacy in improving patient and health service outcomes in this population. However, physiotherapy workforce challenges prevent sustained implementation. METHODS: Our aim was to evaluate the safety, feasibility, acceptability, effectiveness and implementation cost of thrice daily physiotherapy for patients in the acute care setting after hip fracture at two public hospitals. We added twice-daily exercise implemented by an alternative workforce, to usual care consisting of daily mobility practice by a physiotherapist. Sites identified their preferred alternative workforce, with pre-registration physiotherapy students and allied health assistants chosen. We used a mixed methods approach, using the Consolidated Framework for Implementation Research (CFIR) as a determinant framework to guide implementation planning and data collection. We compared hospital length of stay data to a reference cohort. RESULTS: We recruited 25 patients during the study period. Acute care hospital length of stay decreased from 11 days in the reference cohort to 8 days in the BOOST cohort (mean difference - 3.3 days, 95%CI -5.4 to -1.2 days, p = 0.003). Intervention fidelity was 72% indicating feasibility, no safety concerns were attributed to the intervention, and uptake was 96% of all eligible patients. The intervention was acceptable to patients, carers and healthcare providers. This intervention was cost-effective from the acute orthopaedic service perspective. CONCLUSION: Higher daily frequency of physiotherapy can be safely, feasibly and effectively implemented by an alternative workforce for patients in the acute care setting following hip fracture surgery.

Percutaneous Retrieval of an Embolized Transcatheter Mitral Valve Repair Clip Causing ST-Segment Elevation Myocardial Infarction.

Mitral valve repair clip detachment and embolization is a rare phenomenon, with few reported cases. We describe a case of subacute transcatheter mitral valve repair clip embolization presenting as an inferior ST-segment elevation myocardial infarction, with subsequent successful percutaneous device retrieval. (Level of Difficulty: Intermediate.).

The current state of tobacco cessation treatment.

Nicotine addiction and dependence is a chronic relapsing disease driven by addiction to nicotine. Proactive treatment for all tobacco users, regardless of their readiness to quit, is recommended. First-line tobacco cessation medications include nicotine replacement therapy, bupropion, and varenicline. Comprehensive treatment with behavioral interventions and pharmacologic therapy increases success rates of smoking cessation. Although there are many popular alternative treatments, they should not replace or delay the use of known effective therapies.

Vaping-related pulmonary granulomatous disease.

The use of electronic cigarettes, or "vaping," has garnered significant popularity and attention in recent years. Its pulmonary and systemic effects have yet to be fully studied and quantified, and recent reports of vaping-related illnesses and deaths have brought the clinical consequences of vaping into the public spotlight. This report describes the case of a 34 year old woman who presented to clinic with new-onset cough and dyspnea, shortly after beginning to use electronic cigarettes. Imaging demonstrated new micronodular opacities and mediastinal lymphadenopathy, while pathology confirmed granulomatous disease. After she received counseling and successfully quit vaping, her symptoms resolved and repeat imaging demonstrated resolution of parenchymal findings and lymphadenopathy. This case report therefore presents a longitudinal narrative of reversible vaping-related pulmonary granulomatous disease.

Kidney-intrinsic factors determine the severity of ischemia/reperfusion injury in a mouse model of delayed graft function.

Delayed graft function due to transplant ischemia/reperfusion injury adversely affects up to 50% of deceased-donor kidney transplant recipients. However, key factors contributing to the severity of ischemia/reperfusion injury remain unclear. Here, using a clinically relevant mouse model of delayed graft function, we demonstrated that donor genetic background and kidney-intrinsic MyD88/Trif-dependent innate immunity were key determinants of delayed graft function. Functional deterioration of kidney grafts directly corresponded with the duration of cold ischemia time. The graft dysfunction became irreversible after cold ischemia time exceeded six hours. When cold ischemia time reached four hours, kidney grafts displayed histological features reflective of delayed graft function seen in clinical kidney transplantation. Notably, kidneys of B6 mice exhibited significantly more severe histological and functional impairment than kidneys of C3H or BALB/c mice, regardless of recipient strains or alloreactivities. Furthermore, allografts of B6 mice also showed an upregulation of IL-6, neutrophil gelatinase-associated lipocalin, and endoplasmic reticulum stress genes, as well as an increased influx of host neutrophils and memory CD8 T-cells. In contrast, donor MyD88/Trif deficiency inhibited neutrophil influx and decreased the expression of IL-6 and endoplasmic reticulum stress genes, along with improved graft function and prolonged allograft survival. Thus, kidney-intrinsic factors involving genetic characteristics and innate immunity serve as critical determinants of the severity of delayed graft function. This preclinical murine model allows for further investigations of the mechanisms underlying delayed graft function.

e-Cigarette or Vaping Product Use-Associated Lung Injury: Clinical, Radiologic, and Pathologic Findings of 15 Cases.

Since mid-2019, > 2,000 cases of e-cigarette or vaping product use-associated lung injury (EVALI) have been reported. Although initial reports suggested that this entity may be a form of inhalation-related lipoid pneumonia, subsequent studies indicate that EVALI represents various patterns of acute lung injury. Cases of EVALI continue to be reported, and public awareness of the epidemic is increasingly high. However, evidence surrounding optimal management of EVALI remains limited. In this case series, we report 15 cases of EVALI across a spectrum of severity, highlighting key radiologic, pathologic, and cytologic findings, and discuss management implications. In line with national findings, most patients with EVALI in the series vaped liquids containing tetrahydrocannabinol. Our imaging and pathologic findings support the notion that EVALI is a form of acute lung injury.

A Narrative Review of Discrimination Experienced by Medical Students.

INTRODUCTION: The aim of this review was to clarify the nature of discrimination experienced by medical students and identify institutional responses and directions for future research. METHOD: A narrative literature review of first-hand experiences of discrimination reported by medical students across a 10-year time period. RESULTS: Twenty-five reports with different methodologies were included. Discrimination was defined by a wide range of terms. Students had a range of responses to discriminatory treatment and many did not report their experiences. CONCLUSION: Discrimination is a significant issue for medical students in clinical settings. Further research is needed to formulate institutional responses to understanding and addressing discrimination.

Patients' expectations of their anesthesiologists.

OBJECTIVES: To determine the patient's perception of the role of an anesthesiologist and the patient's expectations of their anesthesiologist and their anesthesia care. STUDY DESIGN: Questionnaire survey. METHODS: A total of 170 patients attending the preanesthesia clinic answered a survey prior to their clinic interview and another survey the day after their surgery. The questions pertained to their perception of the role of the anesthesia provider, their expectations, and their level of satisfaction. RESULTS: A majority (>75%) of the participants had high expectations of their anesthesia provider. The satisfaction scores were higher among those who felt that their expectations were met and among those who felt that the anesthesiologist explained to them how they would feel after anesthesia. CONCLUSIONS: Because satisfaction is a fulfillment of one's expectations, understanding what the patient expects from their anesthesiologist is the initial step to improve satisfaction scores. The onus is on the anesthesiologist to educate the patient about their role, to set realistic expectations of the postoperative course, and to involve the patient in decisions regarding their anesthesia care.

A Mouse Model of Vascularized Heterotopic Spleen Transplantation for Studying Spleen Cell Biology and Transplant Immunity.

The spleen is a unique lymphoid organ that plays a critical role in the homeostasis of the immune and hematopoietic systems. Patients that have undergone splenectomy regardless of precipitating causes are prone to develop an overwhelming post-splenectomy infection and experience increased risks of deep venous thrombosis and malignancies. Recently, epidemiological studies indicated that splenectomy might be associated with the occurrence of cardiovascular diseases, suggesting that physiological functions of the spleen have not yet been fully recognized. Here, we introduce a mouse model of vascularized heterotopic spleen transplantation, which not only can be utilized to study the function and behavioral activity of splenic immune cell subsets in different biologic processes, but also can be a powerful tool to test the therapeutic potential of spleen transplantation in certain diseases. The main surgical steps of this model include donor spleen harvest, the removal of recipient native spleen, and spleen graft revascularization. Using congenic mouse strains (e.g., mice with CD45.1/CD45.2 backgrounds), we observed that after syngeneic transplantation, both donor-derived splenic lymphocytes and myeloid cells migrated out of the graft as early as post-operative day 1, concomitant with the influx of multiple types of recipient cells, thus generating a unique chimera.  Despite relatively challenging techniques, this procedure can be performed with >90% success rate. This model allows tracking the fate, longevity, and function of splenocytes during steady state and in a disease setting following a spleen transplantation, thereby offering a great opportunity to discover the distinct role for spleen-derived immune cells in different disease processes.

GutLogo: Agent-based modeling framework to investigate spatial and temporal dynamics in the gut microbiome.

Knowledge of the spatial and temporal dynamics of the gut microbiome is essential to understanding the state of human health, as over a hundred diseases have been correlated with changes in microbial populations. Unfortunately, due to the complexity of the microbiome and the limitations of in vivo and in vitro experiments, studying spatial and temporal dynamics of gut bacteria in a biological setting is extremely challenging. Thus, in silico experiments present an excellent alternative for studying such systems. In consideration of these issues, we have developed a user-friendly agent-based model, GutLogo, that captures the spatial and temporal development of four representative bacterial genera populations in the ileum. We demonstrate the utility of this model by simulating population responses to perturbations in flow rate, nutrition, and probiotics. While our model predicts distinct changes in population levels due to these perturbations, most of the simulations suggest that the gut populations will return to their original steady states once the disturbance is removed. We hope that, in the future, the GutLogo model is utilized and customized by interested parties, as GutLogo can serve as a basic modeling framework for simulating a variety of physiological scenarios and can be extended to capture additional complexities of interest.

Utilizing a Personal Smartphone Custom App to Assess the Patient Health Questionnaire-9 (PHQ-9) Depressive Symptoms in Patients With Major Depressive Disorder.

BACKGROUND: Accurate reporting of patient symptoms is critical for diagnosis and therapeutic monitoring in psychiatry. Smartphones offer an accessible, low-cost means to collect patient symptoms in real time and aid in care. OBJECTIVE: To investigate adherence among psychiatric outpatients diagnosed with major depressive disorder in utilizing their personal smartphones to run a custom app to monitor Patient Health Questionnaire-9 (PHQ-9) depression symptoms, as well as to examine the correlation of these scores to traditionally administered (paper-and-pencil) PHQ-9 scores. METHODS: A total of 13 patients with major depressive disorder, referred by their clinicians, received standard outpatient treatment and, in addition, utilized their personal smartphones to run the study app to monitor their symptoms. Subjects downloaded and used the Mindful Moods app on their personal smartphone to complete up to three survey sessions per day, during which a randomized subset of PHQ-9 symptoms of major depressive disorder were assessed on a Likert scale. The study lasted 29 or 30 days without additional follow-up. Outcome measures included adherence, measured by the percentage of completed survey sessions, and estimates of daily PHQ-9 scores collected from the smartphone app, as well as from the traditionally administered PHQ-9. RESULTS: Overall adherence was 77.78% (903/1161) and varied with time of day. PHQ-9 estimates collected from the app strongly correlated (r=.84) with traditionally administered PHQ-9 scores, but app-collected scores were 3.02 (SD 2.25) points higher on average. More subjects reported suicidal ideation using the app than they did on the traditionally administered PHQ-9. CONCLUSIONS: Patients with major depressive disorder are able to utilize an app on their personal smartphones to self-assess their symptoms of major depressive disorder with high levels of adherence. These app-collected results correlate with the traditionally administered PHQ-9. Scores recorded from the app may potentially be more sensitive and better able to capture suicidality than the traditional PHQ-9.

Low-dose ketamine improves pain relief in patients receiving intravenous opioids for acute pain in the emergency department: results of a randomized, double-blind, clinical trial.

OBJECTIVES: Low-dose ketamine has been used perioperatively for pain control and may be a useful adjunct to intravenous (IV) opioids in the control of acute pain in the emergency department (ED). The aim of this study was to determine the effectiveness of low-dose ketamine as an adjunct to morphine versus standard care with morphine alone for the treatment of acute moderate to severe pain among ED patients. METHODS: A double-blind, randomized, placebo-controlled trial with three study groups was conducted at a large, urban academic ED over a 10-month period. Eligible patients were 18 to 65 years old with acute moderate to severe pain (score of at least 5 out of 10 on the numerical pain rating scale [NRS] and pain duration < 7 days) who were deemed by their treating physician to require IV opioids. The three study groups were: 1) morphine and normal saline placebo (standard care group), 2) morphine and 0.15 mg/kg ketamine (group 1), or 3) morphine and 0.3 mg/kg ketamine (group 2). Participants were assessed at 30, 60, and 120 minutes after study medication administration and received rescue analgesia as needed to target a 50% reduction in pain. The primary outcome measure of pain relief, or pain intensity reduction, was derived using the NRS and calculated as the summed pain-intensity (SPID) difference over 2 hours. The amount and timing of rescue opioid analgesia was evaluated as a secondary outcome. The occurrence of adverse events was also measured. RESULTS: Sixty patients were enrolled (n = 20 in each group). There were no differences between study groups with respect to age, sex, race/ethnicity, preenrollment analgesia, or baseline NRS. Over the 2-hour poststudy medication administration period, the SPIDs were higher (greater pain relief) for the ketamine study groups than the control group (standard care 4.0, interquartile range [IQR] = 1.8 to 6.5; group 1 7.0, IQR = 4.3 to 10.8; and group 2 7.8, IQR = 4.8 to 12.8; p < 0.02). The SPIDs for the ketamine groups were similar (p < 0.46). When compared to standard care, group 2 sustained the reduction in pain intensity up to 2 hours, whereas group 1 was similar to standard care by 2 hours. Similar numbers of patients received rescue analgesia: standard care group, seven of 20, 35%; group 1, four of 20, 20%; and group 2, four of 20, 20% (p = 0.48). Among those receiving rescue analgesia, those in the standard care group received analgesia sooner than either low-dose ketamine group, on average. More participants in the low-dose ketamine groups reported dysphoria and dizziness. CONCLUSIONS: Low-dose ketamine is a viable analgesic adjunct to morphine for the treatment of moderate to severe acute pain. Dosing of 0.3 mg/kg is possibly more effective than 0.15 mg/kg, but may be associated with minor adverse events. Future studies should evaluate additional outcomes, optimum dosing, and use in specific populations.

Efficient and regiospecific syntheses of peptides with piperazic and dehydropiperazic acids via a multicomponent reaction.

Peptides containing N2-acyl piperazic or 1,6-dehydropiperazic acids can be formed efficiently via a novel multicomponent reaction of 1,4,5,6-tetrahydropyridazines, isocyanides, and carboxylic acids. Remarkably, the reaction's induced intramolecularity can enable the regiospecific formation of products with N2-acyl piperazic acid, which counters the intrinsic and troublesome propensity for piperazic acids to react at N1 in acylations. The utility of the methodology is demonstrated in the synthesis of the bicyclic core of the interleukin-1ß converting enzyme inhibitor, Pralnacasan.

Coupler-apodized Bragg-grating add-drop filter.

We demonstrate an apodization technique using tapered coupler gaps in grating-assisted asymmetric couplers, which circumvents the need for tapered waveguide perturbations and enables a higher tolerance to fabrication errors. A high sidelobe suppression ratio of 30 dB has been obtained on the submicrometer silicon-on-insulator platform using a CMOS-compatible photonics process with 193 nm lithography.

Ultra-compact, flat-top demultiplexer using anti-reflection contra-directional couplers for CWDM networks on silicon.

Wavelength-division-multiplexing (WDM) networks with wide channel grids and bandwidths are promising for low-cost, low-power optical interconnects. Wide-bandwidth, single-band (i.e., no free-spectral range) add-drop filters have been developed on silicon using anti-reflection contra-directional couplers with out-of-phase Bragg gratings. Using such filter components, we demonstrate a 4-channel, coarse-WDM demultiplexer with flat passbands of up to 13 nm and an ultra-compact size of 1.2 × 10(-3) mm(2).

Silicon photonic grating-assisted, contra-directional couplers.

We demonstrate, in both theory and experiment, 4-port, electrically tunable photonic filters using silicon contra-directional couplers (contra-DCs) with uniform and phase-shifted waveguide Bragg gratings. Numerical analysis, including both intra- and inter-waveguide couplings, is performed using coupled-mode theory and the transfer-matrix method. The contra-DC devices were fabricated by a CMOS-photonics manufacturing foundry and are electrically tunable using free-carrier injection. A 4-port, grating-based photonic resonator has been obtained using the phase-shifted contra-DC, showing a resonant peak with a 3-dB bandwidth of 0.2 nm and an extinction ratio of 24 dB. These contra-DC devices enable on-chip integration of Bragg-grating-defined functions without using circulators and have great potential for applications such as wavelength-division multiplexing networks and optical signal processing.

Ultra-compact, high-Q silicon microdisk reflectors.

We demonstrate wavelength-selective reflectors based on silicon microdisk resonators integrated with compact Y-branch splitters, using a CMOS-photonics technology. A high quality factor (Q) of ~ 88,000 was measured in the reflection spectrum for a 2.5-µm-radius device with a small footprint of 6 × 17 µm(2) and a wide free-spectral range (FSR) of over 41 nm. As the radius is reduced to 1.5 µm, corresponding to a device footprint of 4 × 15 µm(2), the spectrum shows an ultra-wide FSR of over 71 nm with the compromise of having a reduced Q of ~ 4000. The coupling between a microdisk and a waveguide is numerically investigated. We further propose a multichannel sensing system using cascaded microdisk reflectors.