Operative Versus Nonoperative Management of Acute Pediatric Monteggia Injuries With Complete Ulna Fractures.

Background: The treatment of acute pediatric Monteggia injuries involving a complete fracture of the ulna remains controversial. The purpose of this study is to compare the outcomes of immediate operative fixation to a trial of closed reduction and casting of acute pediatric Monteggia fractures involving complete ulna fractures.

Methods: We performed a retrospective analysis of 73 patients with Monteggia injuries with complete ulna fractures presenting to 2 pediatric trauma centers from 2008 to 2018.

Sagittal Plane Residual Deformity in Pediatric Type II Supracondylar Humerus Fractures.

Introduction: The incidence of residual deformity in the sagittal plane of the humerus (RDSPH) after nonoperative management of type II supracondylar humerus fractures (SCHFs), and the effects of such deformity on the overall arc of motion (AOM) of the elbow, are unknown. Our purpose was to analyze data collected prospectively on a large cohort of type II SCHF's to establish the incidence and extent of RDSPH, and the effects of the deformity on the elbow function, to further support our previously published recommendations on the treatment of type II SCHF.

Methods: The clinical data and radiographs of 1107 pediatric type II SCHFs enrolled in a prospective registry, and followed for a minimum of 8 weeks, were retrospectively reviewed.

Telehealth: a novel approach for the treatment of nondisplaced pediatric elbow fractures.

Telehealth has seldom been used in the field of pediatric orthopaedics. The purpose of this study is to assess the efficacy of telehealth as a tool for the follow-up of children with nondisplaced elbow fractures. We hypothesize that patients treated via telehealth will have comparable clinical outcomes as those treated at our institution, with increased patient satisfaction.

The outcome of in-situ fixation of unstable slipped capital femoral epiphysis.

There is limited information regarding the outcome of in-situ fixation of unstable slipped capital femoral epiphysis (U-SCFE). We aimed to report the outcome of a cohort of patients with U-SCFE that were treated with in-situ fixation, by comparing it to the outcome of patients with stable slipped capital femoral epiphysis (S-SCFE). After Institutional Review Board approval, a retrospective analysis of patients with SCFE that were treated with in-situ fixation at a single institution between 2005 and 2016 was performed.

Intrinsic activation of the vitamin D antimicrobial pathway by M. leprae infection is inhibited by type I IFN.

Following infection, virulent mycobacteria persist and grow within the macrophage, suggesting that the intrinsic activation of an innate antimicrobial response is subverted by the intracellular pathogen. For Mycobacterium leprae, the intracellular bacterium that causes leprosy, the addition of exogenous innate or adaptive immune ligands to the infected monocytes/macrophages was required to detect a vitamin D-dependent antimicrobial activity. We investigated whether there is an intrinsic immune response to M.

A Removable Long-arm Soft Cast to Treat Nondisplaced Pediatric Elbow Fractures: A Randomized, Controlled Trial.

Background: The ideal type of immobilization for nondisplaced pediatric elbow fractures has not been established. We hypothesized that the use of a long-arm cylinder made of soft cast material will result in similar outcomes to those obtained with a traditional long-arm hard cast.

Methods: We randomly assigned 100 consecutive children who presented with a closed, nondisplaced, type I supracondylar humeral fracture or an occult, closed, acute elbow injury, to 1 of 2 groups: group A (n=50) received a long-arm, traditional fiberglass (hard) cast.

Is the "Appropriate Use Criteria" for Type II Supracondylar Humerus Fractures Really Appropriate?

Introduction: The Appropriate Use Criteria for the treatment of supracondylar humerus fractures (SCHFs), developed by American Academy of Orthopaedic Surgeons, recommends pinning for all type II SCHFs. However, previous studies have suggested that, with close follow-up some of the less severe type II SCHF's can be successfully treated without surgery. Our purpose was to analyze data collected prospectively on a large cohort of type II SCHF's.

Interaction of factor V B-domain acidic region with its basic region and with TFPI/TFPI2: Structural insights from molecular modeling studies.

Background: Factor V (FV) B-domain contains an acidic region (FV-AR2) and a basic region (FV-BR), which interact with each other and maintain FV in a procofactor form; removal of either region via deletion/proteolysis results in an active FVa molecule. Tissue factor pathway inhibitor type-1 (TFPI) and type-2 (TFPI2) each contain a C-terminus basic segment homologous to FV-BR; this region in TFPI (and predicted in TFPI2) binds to FV-AR2 in platelet FVa (that lacks FV-BR) with high affinity and inhibits FVa function.

Objectives: To understand molecular interactions between FV-AR2 with FV-BR, TFPI-BR and TFPI2-BR.

Pediatric supracondylar humerus fractures: is surgeon experience a surrogate for the need of open reduction?

Although there are many factors that are likely to influence the need for open reduction and percutaneous pinning (ORPF) in the treatment of pediatric supracondylar humerus fractures (SCHFs), the role of surgeon's experience (as represented by the total number of surgically treated SCHFs) on the need for ORPF has seldom been investigated. We reviewed the data on all completely displaced, pediatric SCHFs that were treated surgically by a single, fellowship-trained, pediatric orthopedic surgeon over the first 10 years of the surgeon's clinical practice. The incidence of ORPF was calculated as the percentage of open reductions among surgically treated, completely displaced, consecutive SCHFs at any given time during the 10-year period.

Isolation of Perivascular Multipotent Precursor Cell Populations from Human Cardiac Tissue.

Multipotent mesenchymal stem/stromal cells (MSC) were conventionally isolated, through their plastic adherence, from primary tissue digests whilst their anatomical tissue location remained unclear. The recent discovery of defined perivascular and MSC cell marker expression by perivascular cells in multiple tissues by our group and other researchers has provided an opportunity to prospectively isolate and purify specific homogenous subpopulations of multipotent perivascular precursor cells. We have previously demonstrated the use of fluorescent activated cell sorting (FACS) to purify microvascular CD146CD34 pericytes and vascular CD34CD146 adventitial cells from human skeletal muscle.

Concerted effects of heterogeneous nuclear ribonucleoprotein C1/C2 to control vitamin D-directed gene transcription and RNA splicing in human bone cells.

Traditionally recognized as an RNA splicing regulator, heterogeneous nuclear ribonucleoprotein C1/C2 (hnRNPC1/C2) can also bind to double-stranded DNA and function in trans as a vitamin D response element (VDRE)-binding protein. As such, hnRNPC1/C2 may couple transcription induced by the active form of vitamin D, 1,25-dihydroxyvitamin D (1,25(OH)D) with subsequent RNA splicing. In MG63 osteoblastic cells, increased expression of the 1,25(OH)D target gene CYP24A1 involved immunoprecipitation of hnRNPC1/C2 with CYP24A1 chromatin and RNA.

Outcomes of ORIF >7 Days After Injury in Displaced Pediatric Lateral Condyle Fractures.

Background: The purpose of the present study was to evaluate the effects of surgical timing on the outcome of pediatric lateral condyle fractures (LCF). We hypothesize that performing open reduction and internal fixation (ORIF) for a displaced LCF between 7 and 14 days after the occurrence of injury does not result in significant changes in outcome, as compared with those treated within the first 7 days.

Methods: A total of 181 pediatric LCFs treated with ORIF, with a mean follow-up of 38 weeks and a mean age of 5 years, were included.

Regenerative Translation of Human Blood-Vessel-Derived MSC Precursors.

Mesenchymal stem/stromal cells (MSCs) represent a promising adult progenitor cell source for tissue repair and regeneration. Their mysterious identity in situ has gradually been unveiled by the accumulating evidence indicating an association between adult multipotent stem/progenitor cells and vascular/perivascular niches. Using immunohistochemistry and fluorescence-activated cell sorting, we and other groups have prospectively identified and purified subpopulations of multipotent precursor cells associated with the blood vessels within multiple human organs.

Variation in practice habits in the treatment of pediatric distal radius fractures.

Distal radius fractures are widespread in the pediatric population. Standardized treatment protocols have not been well defined. We sought to examine the diversity of current practice patterns in the treatment of these fractures by surveying hand, pediatric, and general orthopedic surgeons.

Quantifying vitamin K-dependent holoprotein compaction caused by differential γ-carboxylation using high-pressure size exclusion chromatography.

This study uses high-pressure size exclusion chromatography (HPSEC) to quantify divalent metal ion (X(2+))-induced compaction found in vitamin K-dependent (VKD) proteins. Multiple X(2+) binding sites formed by the presence of up to 12 γ-carboxyglutamic acid (Gla) residues are present in plasma-derived FIX (pd-FIX) and recombinant FIX (r-FIX). Analytical ultracentrifugation (AUC) was used to calibrate the Stokes radius (R) measured by HPSEC.

Stem cell technology for bone regeneration: current status and potential applications.

Continued improvements in the understanding and application of mesenchymal stem cells (MSC) have revolutionized tissue engineering. This is particularly true within the field of skeletal regenerative medicine. However, much remains unknown regarding the native origins of MSC, the relative advantages of different MSC populations for bone regeneration, and even the biologic safety of such unpurified, grossly characterized cells.

Closed Reduction and Percutaneous Pinning of Displaced Pediatric Lateral Condyle Fractures of the Humerus: A Cohort Study.

Background: In treating pediatric lateral condyle fractures (LCFs) of the humerus, closed reduction and percutaneous pinning (CRPP) is an attractive alternative to open reduction and internal fixation (ORIF) because of the potential decrease in tissue injury, shorter surgical times, and faster functional recovery. However, there is limited information available regarding its outcome.

Methods: The data on 191 pediatric LCFs [163 fractures (85%) treated with ORIF (group 1) and 28 fractures (15%) treated with CRPP (group 2)], who were followed for over 12 weeks, was included in the present analysis.

Vitamin D and alternative splicing of RNA.

The active form of vitamin D (1α,25-dihydroxyvitamin D, 1,25(OH)2D) exerts its genomic effects via binding to a nuclear high-affinity vitamin D receptor (VDR). Recent deep sequencing analysis of VDR binding locations across the complete genome has significantly expanded our understanding of the actions of vitamin D and VDR on gene transcription. However, these studies have also promoted appreciation of the extra-transcriptional impact of vitamin D on gene expression.

The Outcome of Surgical Treatment of Multidirectionally Unstable (Type IV) Pediatric Supracondylar Humerus Fractures.

Background: The outcome of multidirectionally unstable (type IV) supracondylar humerus fractures (SCHF) has been rarely described. We aimed to describe several aspects related to the diagnosis, treatment, and outcome of this complex injury.

Methods: We analyzed the clinical and radiographic data on 130 completely displaced SCHF in children, which was collected prospectively over a 6-year period (2007 to 2013), as part of an IRB-approved study.

Cloning of a functional 25-hydroxyvitamin D-1α-hydroxylase in zebrafish (Danio rerio).

Activation of precursor 25-hydroxyvitamin D3 (25D) to hormonal 1,25-dihydroxyvitamin D3 (1,25D) is a pivotal step in vitamin D physiology, catalysed by the enzyme 25-hydroxyvitamin D-1α-hydroxylase (1α-hydroxylase). To establish new models for assessing the physiological importance of the 1α-hydroxylase-25D-axis, we used Danio rerio (zebrafish) to characterize expression and biological activity of the gene for 1α-hydroxylase (cyp27b1). Treatment of day 5 zebrafish larvae with inactive 25D (5-150 nM) or active 1,25D (0.

Platelets contain tissue factor pathway inhibitor-2 derived from megakaryocytes and inhibits fibrinolysis.

Tissue factor pathway inhibitor-2 (TFPI-2) is a homologue of TFPI-1 and contains three Kunitz-type domains and a basic C terminus region. The N-terminal domain of TFPI-2 is the only inhibitory domain, and it inhibits plasma kallikrein, factor XIa, and plasmin. However, plasma TFPI-2 levels are negligible (≤20 pM) in the context of influencing clotting or fibrinolysis.

Isolation of blood-vessel-derived multipotent precursors from human skeletal muscle.

Since the discovery of mesenchymal stem/stromal cells (MSCs), the native identity and localization of MSCs have been obscured by their retrospective isolation in culture. Recently, using fluorescence-activated cell sorting (FACS), we and other researchers prospectively identified and purified three subpopulations of multipotent precursor cells associated with the vasculature of human skeletal muscle. These three cell populations: myogenic endothelial cells (MECs), pericytes (PCs), and adventitial cells (ACs), are localized respectively to the three structural layers of blood vessels: intima, media, and adventitia.