Holocephalan (Chondrichthyes) dental plates with hypermineralized dentine as a substitute for missing teeth through developmental plasticity.

All extant holocephalans (Chimaeroidei) have lost the ability to make individual teeth, as tooth germs are not part of the embryonic development of the dental plates or of their continuous growth. Instead, a hypermineralized dentine with a unique mineral, whitlockin, is specifically distributed within a dentine framework into structures that give the dental plates their distinctive, species-specific morphology. Control of the regulation of this distribution must be cellular, with a dental epithelium initiating the first outer dentine, and via contact with ectomesenchymal tissue as the only embryonic cell type that can make dentine.

Estimation of subject coregistration errors during multimodal preclinical imaging using separate instruments: origins and avoidance of artifacts.

We use high-resolution [Formula: see text] data in multiple experiments to estimate the sources of error during coregistration of images acquired on separate preclinical instruments. In combination with experiments with phantoms, we completed imaging on mice, aimed at identifying the possible sources of registration errors, caused either by transport of the animal, movement of the animal itself, or methods of coregistration. The same imaging cell was used as a holder for phantoms and animals.

Radiographic and Clinical Assessment of Intramedullary Nail Fixation for the Treatment of Unstable Metacarpal Fractures.

Background: The purpose of the article was to evaluate clinical and radiographic outcomes in a case series of unstable metacarpal fractures treated with flexible intramedullary nail (IMN) fixation.

Methods: A total of 55 patients with unstable metacarpal fractures between 2003 and 2010 were treated with IMN fixation and followed for a minimum of 1 year. The outcomes were assessed via a radiological study of longitudinal and angular collapse, Disabilities of the Arm, Shoulder, and Hand (DASH) score, total active range of motion (ROM) of the wrist, and grip strength testing.

Effects of Transendocardial Stem Cell Injection on Ventricular Proarrhythmia in Patients with Ischemic Cardiomyopathy: Results from the POSEIDON and TAC-HFT Trials.

Transendocardial stem cell injection in patients with ischemic cardiomyopathy (ICM) improves left ventricular function and structure but has ill-defined effects on ventricular arrhythmias. We hypothesized that mesenchymal stem cell (MSC) implantation is not proarrhythmic. Post hoc analyses were performed on ambulatory ECGs collected from the POSEIDON and TAC-HFT trials.

Differences Between Access to Follow-Up Care and Inappropriate Shocks Based on Insurance Status of Implantable Cardioverter Defibrillator Recipients.

Differences in implantable cardioverter defibrillator (ICD) utilization based on insurance status have been described, but little is known about postimplant follow-up patterns associated with insurance status and outcomes. We collected demographic, clinical, and device data from 119 consecutive patients presenting with ICD shocks. Insurance status was classified as uninsured/Medicaid (uninsured) or private/Health Maintenance Organization /Medicare (insured).

Cryoballoon versus Radiofrequency Catheter Ablation in Atrial Fibrillation: A Meta-Analysis.

Introduction: Radiofrequency (RF) and cryoballoon (CB) catheter ablation are effective for pulmonary vein isolation (PVI) in atrial fibrillation (AF). This report presents an updated meta-analysis comparing the efficacy and safety of CB versus RF ablations in AF.

Methods: Databases and conference abstracts were systematically searched for studies that directly compared CB and RF PVI, and reported safety or efficacy outcomes in follow-up ≥12 months.

ICD discrimination of SVT versus VT with 1:1 V-A conduction: A review of the literature.

Inappropriate ICD shocks are associated with increased mortality. They also impair patients' quality of life, increase hospitalizations, and raise health-care costs. Nearly 80% of inappropriate ICD shocks are caused by supraventricular tachycardia.

Activated WNT signaling in postnatal SOX2-positive dental stem cells can drive odontoma formation.

In common with most mammals, humans form only two dentitions during their lifetime. Occasionally, supernumerary teeth develop in addition to the normal complement. Odontoma represent a small group of malformations containing calcified dental tissues of both epithelial and mesenchymal origin, with varying levels of organization, including tooth-like structures.

Management of Ventricular Arrhythmias in Patients with Mechanical Ventricular Support Devices.

The use of mechanical ventricular support devices in the management of patients with advanced heart failure continues to increase. These devices have been shown to prolong life as a destination therapy and to increase survival when used as a bridge to transplantation. However, they are associated with a high rate of complications, including bleeding, infection, device malfunction, and ventricular arrhythmias (VAs).

Arrhythmias in chagasic cardiomyopathy.

Chagas disease, a chronic parasitosis caused by the protozoa Trypanosoma cruzi, is an increasing worldwide problem because of the number of cases in endemic areas and the migration of infected individuals to more developed regions. Chagas disease affects the heart through cardiac parasympathetic neuronal depopulation, immune-mediated myocardial injury, parasite persistence in cardiac tissue with secondary antigenic stimulation, and coronary microvascular abnormalities causing myocardial ischemia. A lack of knowledge exists for risk stratification, management, and prevention of ventricular arrhythmias in patients with chagasic cardiomyopathy.

Reduced dosage of ERF causes complex craniosynostosis in humans and mice and links ERK1/2 signaling to regulation of osteogenesis.

The extracellular signal-related kinases 1 and 2 (ERK1/2) are key proteins mediating mitogen-activated protein kinase signaling downstream of RAS: phosphorylation of ERK1/2 leads to nuclear uptake and modulation of multiple targets. Here, we show that reduced dosage of ERF, which encodes an inhibitory ETS transcription factor directly bound by ERK1/2 (refs. 2,3,4,5,6,7), causes complex craniosynostosis (premature fusion of the cranial sutures) in humans and mice.

Familial atypical cold urticaria: description of a new hereditary disease.

Background: Acquired cold urticaria (ACU) is usually a self-limited, sporadic, cutaneous disease diagnosed based on history and a positive cold stimulation time test (CSTT) result. We describe 3 unrelated families (A, B, and C) with lifelong atypical cold urticaria distinguished from ACU and familial cold autoinflammatory syndrome.

Objective: We sought to describe a new hereditary disease of cold urticaria and study its pathogenesis.

Skeletal analysis of the Fgfr3(P244R) mouse, a genetic model for the Muenke craniosynostosis syndrome.

Muenke syndrome, defined by heterozygosity for a Pro250Arg substitution in fibroblast growth factor receptor 3 (FGFR3), is the most common genetic cause of craniosynostosis in humans. We have used gene targeting to introduce the Muenke syndrome mutation (equivalent to P244R) into the murine Fgfr3 gene. A rounded skull and shortened snout (often skewed) with dental malocclusion was observed in a minority of heterozygotes and many homozygotes.

Mohs micrographic surgery is accurate 95.1% of the time for melanoma in situ: a prospective study of 167 cases.

Background: Mohs micrographic surgery (MMS) represents a promising option for treatment of melanoma in situ (MIS). However, interpretation of melanocytic lesions by fresh frozen sections may be difficult.

Objective: The objective of this study was to determine if margins called clear by MMS were clear by subsequent paraffin-embedded sections and to compare cure rate with available data for MMS and standard excision.

Office surgery incidents: what seven years of Florida data show us.

Background: In the wake of increased media attention focusing on human error in medicine, numerous state medical boards and legislatures have drafted, and are continuing to draft, regulations aimed at protecting patients undergoing procedures in the office setting. These regulations will have a considerable impact on patient access to medically necessary procedures, and any regulations should be based on good data. This report summarizes 7 years of prospective data from the state of Florida, the best data available on office surgery incidents.

Sonic hedgehog in the pharyngeal endoderm controls arch pattern via regulation of Fgf8 in head ectoderm.

Fgf8 signalling is known to play an important role during patterning of the first pharyngeal arch, setting up the oral region of the head and then defining the rostral and proximal domains of the arch. The mechanisms that regulate the restricted expression of Fgf8 in the ectoderm of the developing first arch, however, are not well understood. It has become apparent that pharyngeal endoderm plays an important role in regulating craniofacial morphogenesis.