Acellular dermal regeneration template for soft tissue reconstruction of the digits.

PURPOSE: Trauma to the digits often leaves soft tissue defects with exposed bone, joint, and/or tendon that require soft tissue replacement. The objective of this study was to evaluate the effectiveness of acellular dermal regeneration template combined with full-thickness skin grafting for soft tissue reconstruction in digital injuries with soft tissue defects. METHODS: Acellular dermal regeneration template was used to reconstruct digital injuries with exposed bone, joint, tendon, and/or hardware not amenable to treatment with healing by secondary intention, rotation flaps, or primary skin grafts. Acellular dermal regeneration template was applied to 21 digits in 17 patients. Nineteen digits had exposed bone, 8 digits had exposed tendon, 6 digits had exposed joints, and 2 digits had exposed hardware. The acellular dermal regeneration template was sutured over the soft tissue defect. Over 3 weeks, a neodermis formed. The superficial silicone layer of the acellular dermal regeneration template was removed, and the digits received full-thickness epidermal autografting with cotton bolster. RESULTS: The duration of postoperative follow-up extended to a minimum of 12 months. For the injury sites where acellular dermal regeneration template was applied, the total area of application ranged from 1 cm(2) to 24 cm(2), with the largest individual site measuring 12 cm(2). Twenty of 21 digits demonstrated 100% incorporation of the acellular dermal regeneration template skin substitute. One digit that had sustained multilevel trauma developed necrosis requiring revision amputation. Full-thickness epidermal autografting was performed an average of 24 days after acellular dermal regeneration template skin substitute application and demonstrated a 100% take in 16 of 20 digits and partial graft loss of 15% to 25% in 4 of 20 digits that did not require further treatment. CONCLUSIONS: Acellular dermal regeneration template combined with secondary full-thickness skin grafting is an effective method of skin reconstruction in complex digital injuries with soft tissue defects involving exposed bone, tendon, and joint. The neodermis increases tissue bulk and facilitates epidermal autografting with digital injuries that otherwise would require flap coverage or skeletal shortening of the digit. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV

The Hand in Art: Hand of Hope

The “Hand of Hope” (Fig. 1) statue was commissioned for display in the street-level lobby of my practice, The Philadelphia Hand Center, by its founders, James M. Hunter, MD, and Lawrence H. Schneider, MD. The work became a hallmark of the practice’s former Walnut Street location as well as a recognizable feature of its neighborhood. After a sojourn of several years residing next to Thomas Eakins’ portrait of the operative theatre in “The Gross Clinic,” at Thomas Jefferson University, the sculpture has returned to grace our office’s lobby in the historic Benjamin Franklin Hotel

Surgical Correction of Severe Bilateral Thumb Pincer-Nail Deformity

A 53 year old woman presented to the office with complaint of severe bilateral thumb nail pain and the deformity shown (Figure 1). She denied previous trauma to her thumb nails and had no history of previous bacterial or fungal infections of her nails. Based on the curvature of her nails, which increased from proximal to distal, a diagnosis of bilateral thumb pincer nail deformity was made

The Impact of Video Conference on Orthopaedic Resident Education: A Survey

Background: Covid and required social distancing has accelerated the use of video conferencing. We hypothesized that residents and faculty would be less receptive to the video lecture format and prefer traditional didactic methods. Methods: A 16-question anonymous survey was distributed nationally to orthopaedic residents and faculty. The survey collected basic demographic information such as, level in training, gender, and age. We then asked the respondent to rate their agreement or disagreement with 8 statements on a Likert scale (1-5) about video conferencing regarding orthopedic education. Likert scale responses were evaluated using basic descriptive statistics. Respondents were divided into groups of faculty and residents. Residents were subdivided into junior residents (PGY-1s and PGY-2s) and senior residents (PGY-3s, PGY-4s, and PGY-5s). A Wilcoxon rank sum test was used for the Likert scale type questions and a Fisher’s exact test was used for the pros/cons questions to evaluate for a difference in responses between groups. Results: A total of 123 residents or faculty responded to the survey. One was excluded because only the demographics section was completed, leaving 122 respondents. Respondents were found to prefer the traditional didactics compared to the new virtual format (p Conclusions: Orthopaedic residents and faculty do not prefer the new virtual didactic format compared to the traditional approach. Level of Evidence: Level IV Cross-Sectional Stud

Excision of a Rare Triquetral Body Fracture Nonunion

Aside from the more common dorsal avulsion fractures, isolated triquetral body fractures are a rare injury and often missed. When they are identified, conservative treatment via immobilization is often the standard of care for initial treatment. Rarely, triquetral body fractures can develop into symptomatic nonunions, causing considerable pain and disability. Multiple classification schemes have been described to categorize triquetrum fractures; however, distal triquetrum fractures fit into none of the established models. There is scarce literature describing treatment of triquetral body fracture nonunions. The few reports that exist often use a variation of open reduction internal fixation with or without grafting as treatment. We present the case of an unusual triquetral body fracture nonunion that was successfully treated via surgical excision of the ununited distal fragment

The role of karyopherins in the regulated sumoylation of septins

In the yeast Saccharomyces cerevisiae, several components of the septin ring are sumoylated during anaphase and then abruptly desumoylated at cytokinesis. We show that septin sumoylation is controlled by the interactions of two enzymes of the sumoylation pathway, Siz1p and Ulp1p, with the nuclear transport machinery. The E3 ligase Siz1p is imported into the nucleus by the karyopherin Kap95p during interphase. In M phase, Siz1p is exported from the nucleus by the karyopherin Kap142p/Msn5p and subsequently targeted to the septin ring, where it participates in septin sumoylation. We also show that the accumulation of sumoylated septins during mitosis is dependent on the interactions of the SUMO isopeptidase Ulp1p with Kap121p and Kap95p–Kap60p and the nuclear pore complex (NPC). In addition to sequestering Ulp1 at the NPC, Kap121p is required for targeting Ulp1p to the septin ring during mitosis. We present a model in which Ulp1p is maintained at the NPC during interphase and transiently interacts with the septin ring during mitosis

Transgene-induced CCWGG methylation does not alter CG methylation patterning in human kidney cells

Several reports suggest that C(m)CWGG methylation tends not to co-exist with (m)CG methylation in human cells. We have asked whether or not methylation at CCWGG sites can influence CG methylation. DNA from cells expressing an M.EcoRII–GFP fusion was actively methylated at CCWGG sites. CG methylation as measured by R.HpaII/R.MspI ratios was unchanged in cells expressing the transgene. Cloned representatives of C(m)CWGG methylated DNA often contained, or were adjacent to an ALU repeat, suggesting that M.EcoRII-GFP actively methylated gene-rich R-band DNA. The transgenic methyltransferase applied C(m)CWGG methylation to a representative human promoter that was heavily methylated at CG dinucleotides (the SERPINB5 promoter) and to a representative promoter that was essentially unmethylated at CG dinucleotides (the APC promoter). In each case, the CG methylation pattern remained in its original state, unchanged by the presence of neighboring C(m)CWGG sites. Q-PCR measurements showed that RNA expression from the APC gene was not significantly altered by the presence of C(m)CWGG in its promoter. Kinetic studies suggested that an adjacent C(m)CWGG methylation site influences neither the maintenance nor the de novo methylation activities of purified human Dnmt1. We conclude that C(m)CWGG methylation does not exert a significant effect on CG methylation in human kidney cells

GiA Roots: Software for the high throughput analysis of plant root system architecture

Background: Characterizing root system architecture (RSA) is essential to understanding the development and function of vascular plants. Identifying RSA-associated genes also represents an underexplored opportunity for crop improvement. Software tools are needed to accelerate the pace at which quantitative traits of RSA are estimated from images of root networks.Results: We have developed GiA Roots (General Image Analysis of Roots), a semi-automated software tool designed specifically for the high-throughput analysis of root system images. GiA Roots includes user-assisted algorithms to distinguish root from background and a fully automated pipeline that extracts dozens of root system phenotypes. Quantitative information on each phenotype, along with intermediate steps for full reproducibility, is returned to the end-user for downstream analysis. GiA Roots has a GUI front end and a command-line interface for interweaving the software into large-scale workflows. GiA Roots can also be extended to estimate novel phenotypes specified by the end-user.Conclusions: We demonstrate the use of GiA Roots on a set of 2393 images of rice roots representing 12 genotypes from the species Oryza sativa. We validate trait measurements against prior analyses of this image set that demonstrated that RSA traits are likely heritable and associated with genotypic differences. Moreover, we demonstrate that GiA Roots is extensible and an end-user can add functionality so that GiA Roots can estimate novel RSA traits. In summary, we show that the software can function as an efficient tool as part of a workflow to move from large numbers of root images to downstream analysis

Activation of the Calcium Sensing Receptor Decreases Secretagogue-Induced Fluid Secretion in the Rat Small Intestine

BackgroundThe calcium-sensing receptor (CaSR) has been localized and characterized in numerous tissues throughout the body. In the mammalian gastrointestinal tract, the CaSR is known to act as a nutrient sensor and has recently been found to play a role in intestinal fluid and electrolyte balance. This study aims to demonstrate the functionality of the CaSR as a modulator of fluid secretion and absorption along the small intestine.MethodsSmall intestine regions (proximal, middle, and distal) were isolated from Sprague Dawley rats and loaded into an ex vivo intestinal perfusion device that provides independent intraluminal and extraluminal (serosa/basolateral) perfusion. The regions were perfused with 5 and 7 mM of Ca2+, both in the presence and absence of forskolin (FSK), a potent secretagogue. Control experiments were conducted with intraluminal perfusate containing standard Ringer-HEPES buffer with a physiological concentration of Ca2+ (1 mM). A second set of comparison experiments was performed with intraluminal perfusates containing AC-265347, a CaSR activator and agonist, in the presence of FSK. In all experimental conditions, the intraluminal perfusate contained fluorescein isothiocyanate (FITC)-inulin, a nonabsorbable fluorescent marker of secretion and/or absorption. Intraluminal fluorescence signal was utilized as a measure of water movement at the start of the experiment and every 15 min for 90 min.ResultsUnder physiological conditions, increasing the concentration of Ca2+ in the luminal perfusate reduced intestinal fluid secretion in all regions. At a Ca2+ concentration of 7 mM, net fluid absorption was observed in all regions. In the presence of FSK, 5 mM Ca2+ significantly decreased fluid secretion and 7 mM Ca2+ abolished FSK-induced fluid secretion. Intraluminal perfusion with 5 mM Ca2+ was as effective as AC-265347, in reducing secretagogue-induced fluid hypersecretion in the proximal and middle regions.ConclusionThis study concludes that apical CaSR is active along the small intestine. Its activation by Ca2+ and/or calcimimetics reduces fluid secretion in a dose-dependent manner, with higher Ca2+ concentrations, or application of a calcimimetic, leading to fluid absorption. We furthermore show that, in the presence of FSK, receptor activation abates FSK secretagogue-induced fluid secretion. This presents a new therapeutic target to address secretory diarrheal illnesses

Search for Higgs Bosons in e+e- Collisions at 183 GeV

The data collected by the OPAL experiment at sqrts=183 GeV were used to search for Higgs bosons which are predicted by the Standard Model and various extensions, such as general models with two Higgs field doublets and the Minimal Supersymmetric Standard Model (MSSM). The data correspond to an integrated luminosity of approximately 54pb-1. None of the searches for neutral and charged Higgs bosons have revealed an excess of events beyond the expected background. This negative outcome, in combination with similar results from searches at lower energies, leads to new limits for the Higgs boson masses and other model parameters. In particular, the 95% confidence level lower limit for the mass of the Standard Model Higgs boson is 88.3 GeV. Charged Higgs bosons can be excluded for masses up to 59.5 GeV. In the MSSM, mh > 70.5 GeV and mA > 72.0 GeV are obtained for tan{beta}>1, no and maximal scalar top mixing and soft SUSY-breaking masses of 1 TeV. The range 0.8 < tanb < 1.9 is excluded for minimal scalar top mixing and m{top} < 175 GeV. More general scans of the MSSM parameter space are also considered.Comment: 49 pages. LaTeX, including 33 eps figures, submitted to European Physical Journal