Emergence of fractal geometries in the evolution of a metabolic enzyme.

Fractals are patterns that are self-similar across multiple length-scales. Macroscopic fractals are common in nature; however, so far, molecular assembly into fractals is restricted to synthetic systems. Here we report the discovery of a natural protein, citrate synthase from the cyanobacterium Synechococcus elongatus, which self-assembles into Sierpiński triangles.

Pulmonary Vein Isolation in Elderly Patients ≥ 75 Years: A Propensity Score-Matched Analysis With Focus on Differences Among Atrial Fibrillation Types.

Background: Age is a major risk factor for development of atrial fibrillation (AF) and associated with increased recurrence rates in the setting of rhythm control. Current data tend to support catheter ablation in elderly patients, but uncertainties exist regarding efficacy and safety of ablation in elderly patients.

Methods: This was a prospective single-centre observational study with propensity score matching (PSM) to investigate the influence of age on efficacy and safety of cryoballoon ablation (CBA) stratified by age (< 75 years vs ≥ 75 years) and AF phenotype (paroxysmal vs persistent).

Oral Antibiotics for Treatment of Gram-Negative Bacteremia in Solid Organ Transplant Recipients: A Propensity Score Weighted Retrospective Observational Study.

Background: We assessed the safety and efficacy of oral antibiotic step-down therapy for uncomplicated gram-negative blood stream infections in solid-organ transplant recipients.

Methods: We identified all solid-organ transplant recipients within the Massachusetts General and Brigham and Women's Hospital systems from 2016 to 2021 with uncomplicated gram-negative bacteremia involving an organism susceptible to an acceptably bioavailable oral antibiotic agent. Using inverse probability of treatment-weighted models based on propensity scores adjusting for potential clinical confounders, we compared outcomes of those transitioned to oral antibiotics with those who continued intravenous (IV) therapy for the duration of treatment.

Cryoballoon pulmonary vein isolation for atrial fibrillation in obese patients: A non-inferiority analysis.

Background: Patients with obesity are at higher risk of developing atrial fibrillation (AF) and benefit from radiofrequency ablation. Potentially, cryoballoon ablation (CBA) may be equally effective and safe in such patients.

Methods: We conducted a prospective, single-center study to investigate whether CBA for pulmonary vein isolation is as effective and safe in obese patients as it is in non-obese controls.

Tarsal Navicular Bone Stress Injuries: A Multicenter Case Series Investigating Clinical Presentation, Diagnostic Approach, Treatment, and Return to Sport in Adolescent Athletes.

Background: Tarsal navicular bone stress injuries (BSIs) are considered "high risk" because of prolonged healing times and higher rates of nonunion in adult populations but, to our knowledge, have not been comprehensively examined in adolescent athletes.

Purpose: To describe the characteristics of tarsal navicular BSIs in adolescents.

Study Design: Case series; Level of evidence, 4.

Isolated abnormal FEF75% detects unsuspected bronchiolar obstruction in CF children.

Background: Physiologic detection of bronchiolar obstruction in children with cystic fibrosis (CF) may be clinically unsuspected because of normal routine spirometry despite bronchiectasis on lung CT.

Methods: Children from two accredited CF facilities had spirometry obtained every 3 months when clinically stable. Pre-bronchodilator maximum expiratory flow volume curves were retrospectively analyzed over 16 years to detect an isolated abnormal FEF75%, despite normal routine spirometry.

Delayed Migration of Onyx Embolic Agent after Preoperative Embolization of an Arteriovenous Malformation in a Pediatric Patient: A Case Report and Review of the Literature.

Introduction: Brain arteriovenous malformations (AVMs) are increasingly being treated with Onyx liquid embolic agent (Onyx, Medtronic, Inc.). The phenomenon of delayed Onyx migration is not well documented in the literature.

Stress Injuries of the Knee.

Stress injuries to the bone and physis of the knee are common in the active adolescent patient and can be broken down into bone stress injuries (BSIs) and chronic physeal stress injuries. BSIs result from prolonged, repetitive bone loading, whereas chronic physeal stress injuries develop from repetitive loading to the apophysis or epiphysis. Most stress injuries of the knee resolve with relative rest but will occasionally need surgical intervention in more severe cases.

Process optimization for atrial fibrillation ablation.

Aims: In the light of an increasing prevalence of atrial fibrillation (AF) and growing evidence for the superiority of early invasive rhythm control, the demand for ablation therapy is rising. Accordingly, ablation centres will have to maximize their capacity by either adding electrophysiology laboratory resources or optimizing process management. In order to optimize process management, we applied "Lean Six Sigma" method to a single ablation center.

Retrospective Review of Radiographic Imaging of Tibial Bony Stress Injuries in Adolescent Athletes With Positive MRI Findings: A Comparative Study.

Background: It is difficult to diagnose and grade bony stress injury (BSI) in the athletic adolescent population without advanced imaging. Radiographs are recommended as a first imaging modality, but have limited sensitivity and, even when findings are present, advanced imaging is often recommended.

Hypothesis: It was hypothesized that the significance of radiographs is underestimated for BSI in the adolescent with positive clinical examination and history findings.

Octogenarians undergoing pancreaticoduodenectomy: Assessing outcomes, disposition, and timing of chemotherapy.

Background: Inclusion of pancreaticoduodenectomy has demonstrated higher rates of curative treatment in pancreatic cancer, yet prior research has suggested increased postoperative complications in octogenarians (patients older than 80 years). This study aimed to understand the impact of age on patients undergoing a pancreaticoduodenectomy, focusing on postoperative outcomes and return to intended oncologic treatment.

Materials And Methods: We conducted a single-institution retrospective cohort study for patients undergoing pancreaticoduodenectomy from 2007 to 2018.

Case report and literature review of BRAF-V600 inhibitors for treatment of papillary craniopharyngiomas: A potential treatment paradigm shift.

What Is Known And Objective: The BRAF-V600E genetic mutation offers a potential targeted therapy for the treatment of papillary craniopharyngiomas.

Case Summary: A 35-year-old man underwent a craniotomy and subtotal resection of a large BRAF-V600E-positive papillary craniopharyngioma before referral to our institution. Our treatment included the BRAF-V600 inhibitor dabrafenib mesylate (75 mg, twice/day) and trametinib dimethyl sulfoxide (2 mg/day).

Stigma and cervical cancer prevention: A scoping review of the U.S. literature.

Cervical cancer is preventable through HPV vaccination and screening however, uptake falls below national targets. A scoping review was conducted to describe stigmas related to HPV infection and vaccination and cervical cancer and screening in the US. Results were organized into the domains proposed by Stangl and colleagues' Health Stigma and Discrimination Framework.

Procedural complications in patients undergoing microsurgical treatment of unruptured intracranial aneurysms: a single-center experience with 1923 aneurysms.

Background: With the growing use of endovascular therapy (EVT) to manage unruptured intracranial aneurysms (IAs), detailed information regarding periprocedural complication rates of microsurgical clipping and EVT becomes increasingly important in determining the optimal treatment for individual cases. We report the complication rates associated with open microsurgery in a large series of unruptured IAs and highlight the importance of maintaining surgical skill in the EVT era.

Methods: We reviewed all cases of unruptured IAs treated with open microsurgery by a single neurosurgeon between July 1997 and June 2019.

Photobiomodulation and diabetic foot and lower leg ulcer healing: A narrative synthesis.

Purpose: To provide a comprehensive narrative review and critical appraisal of research investigating photobiomodulation (PBM), formerly known as low level laser therapy which includes lasers and light emitting diodes (LEDs), as a treatment to promote diabetic foot and lower leg ulcer (DFU) healing for humans.

Materials And Methods: Pubmed, CINAHL, Scopus, and OVID Medline databases were used to find relevant studies published between January 2000 and January 2020. Reference lists of identified articles were scanned for additional studies that might have been missed in the database searches.

Traumatic epidural hematoma treated with endovascular coil embolization.

Background: Traumatic cerebrovascular injury may result in epidural hematoma (EDH) from laceration of the middle meningeal artery (MMA), which is a potentially life-threatening emergency. Treatment ranges from surgical evacuation to conservative management based on a variety of clinical and imaging factors.

Case Description: A 14-year-old male presented to our institution after falling from his bicycle with traumatic subarachnoid hemorrhage and a right frontotemporal EDH.

CT cisternography to visualize epidermoid tumors for stereotactic radiosurgery treatment planning.

The visualization of intracranial epidermoid tumors is often limited by difficulties associated with distinguishing the tumor from the surrounding cerebrospinal fluid using traditional computed tomography (CT) or magnetic resonance imaging (MRI) modalities. This report describes our experience using CT cisternography to visualize intracranial epidermoid tumors in three illustrative cases. CT cisternography of the epidermoid tumor provides more clarity and precision compared to traditional neuroimaging modalities.

Neoplastic cerebral aneurysm from triple-negative breast cancer: A case report.

Background: We present a rare case of a ruptured neoplastic aneurysms (NCA) caused by metastatic spread of triple-negative breast cancer (TNBC) in a female patient in her 60s. The patient had a medical history of TNBC and presented to the emergency department after experiencing 3 days of persistent headache.

Case Description: Head computed tomography (CT) revealed a small volume subarachnoid hemorrhage and digital subtraction angiography revealed a 3.

Transport of patients with giant disfiguring cranial tumors from Africa to the US for collaborative multidisciplinary treatment.

Background: Giant disfiguring cranial tumors are exceptionally rare and develop over the course of many years, typically in patients who lack access to medical care. Here, we describe four patients who were flown to our center for treatment by a multidisciplinary surgical team, who had previously been turned down for treatment at multiple international centers in Africa, Europe, and the United States (US) due to complexity and financial concerns. The case series describes socioeconomic implications and the feasibility of offering such care to patients from outside the US.