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Introduction: Dynamization of proximal femoral nailing by removal of distal interlocking is one of the recommended treatment options for nonunions of femur fractures. However, in certain inter-/subtrochanteric fractures, gliding of the nail along the femoral shaft is blocked by lateral femoral cortical support of the lag screw. For these cases, Biber et al. proposed lateral cortical notching (LCN), in which the supporting lateral bone is removed. This study investigates the biomechanical effect of LCN on gliding of proximal femoral nailing and stress distribution at the bone/implant interface., Materials and Methods: In this finite element analysis a three-dimensional model of an unstable intertrochanteric fracture with proximal femoral nailing without distal interlocking was simulated using the FebioStudio software suite. To simulate LCN, the lag screw hole was lengthened to 15.34 mm at the lateral cortex. Displacement of the nail along the femoral shaft axis and von Mises stress distribution were compared between LCN model and standard implantation model., Results: Displacement of the nail along the femoral shaft axis was higher in the LCN model than in the standard implantation model (0.48 mm vs. 0.07 mm). Highest von Mises stresses of 176-178 MPa at the implant and of 52-81 MPa at the proximal femur were detected. Maximum von Mises stresses of the implant were comparable at all sides, except for a reduced von Mises stress at the lateral inferior side in the LCN model (80 vs. 102 MPa). At the inferior lateral screw hole and the anterior/posterior lateral screw hole maximum von Mises stress was reduced in the LCN model (2 vs. 49 MPa and 52 vs. 81 MPa), whereas the maximum von Mises stress at the inferior medial screw hole was higher in the LCN model than in the standard implantation model (53 vs. 27 MPa)., Conclusions: Lateral cortical notching facilitates gliding of a distally dynamized proximal femoral nail along the femoral shaft axis in intertrochanteric fractures. Additionally, the lack of lateral cortical bone support at the lag screw reduces von Mises stress at the bone/implant interface and thus could lower the risk for implant breakage and peri‑implant fractures., Competing Interests: Declaration of Competing Interest KS and CL are employees of Swemac Innovation (Germany) GmbH. The authors have no competing interests to declare that are relevant to the content of this article., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Pro/Ala-rich sequences (PAS) are polypeptides that were developed as a biological alternative to poly-ethylene glycol (PEG) to generate biopharmaceuticals with extended plasma half-life. Like PEG, PAS polypeptides are conformationally disordered and show high solubility in water. Devoid of any charged or prominent hydrophobic side chains, these biosynthetic polymers represent an extreme case of intrinsically disordered proteins. Despite lack of immunogenicity of PAS tags in numerous animal studies we now succeeded in generating monoclonal antibodies (MAbs) against three different PAS versions. To this end, mice were immunized with a PAS#1, P/A#1 or APSA 40mer peptide conjugated to keyhole limpet hemocyanin as highly immunogenic carrier protein. In each case, one MAb with high binding activity and specificity towards a particular PAS motif was obtained. The apparent affinity was strongly dependent on the avidity effect and most pronounced for the bivalent MAb when interacting with a long PAS repeat. X-ray structural analysis of four representative anti-PAS Fab fragments in complex with their cognate PAS epitope peptides revealed interactions dominated by hydrogen bond networks involving the peptide backbone as well as multiple Van der Waals contacts arising from intimate shape complementarity. Surprisingly, Ala, the L-amino acid with the smallest side chain, emerged as a crucial feature for epitope recognition, contributing specific contacts at the center of the paratope in several anti-PAS complexes. Apart from these insights into how antibodies can recognize feature-less peptides without secondary structure, the MAbs characterized in this study offer valuable reagents for the preclinical and clinical development of PASylated biologics., (Copyright © 2021 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Acute myeloid leukemia is characterized by the accumulation of clonal myeloid blast cells unable to differentiate into mature leukocytes. Chemotherapy induces remission in the majority of patients, but relapse rates are high and lead to poor clinical outcomes. Because this is primarily caused by chemotherapy-resistant leukemic stem cells (LSCs), it is essential to eradicate LSCs to improve patient survival. LSCs have predominantly been studied at the transcript level, thus information about posttranscriptionally regulated genes and associated networks is lacking. Here, we extend our previous report on LSC proteomes to healthy age-matched hematopoietic stem and progenitor cells (HSPCs) and correlate the proteomes to the corresponding transcriptomes. By comparing LSCs to leukemic blasts and healthy HSPCs, we validate candidate LSC markers and highlight novel and potentially targetable proteins that are absent or only lowly expressed in HSPCs. In addition, our data provide strong evidence that LSCs harbor a characteristic energy metabolism, adhesion molecule composition, as well as RNA-processing properties. Furthermore, correlating proteome and transcript data of the same individual samples highlights the strength of proteome analyses, which are particularly potent in detecting alterations in metabolic pathways. In summary, our study provides a comprehensive proteomic and transcriptomic characterization of functionally validated LSCs, blasts, and healthy HSPCs, representing a valuable resource helping to design LSC-directed therapies., (© 2020 by The American Society of Hematology.)

Amanitin-based ADCs represent a new class of ADCs using a novel mode of action. This payload introduces a novel mode of action into oncology therapy, the inhibition of RNA Polymerase II. The high potency of the toxin leads to highly efficacious ADCs. The development of the technology around this toxin will be described. These developments support the clinical development of amanitin-based ADCs by using a toxin with a new mode of action and with a favorable therapeutic index. HDP-101 is an Amanitin based ADC directed against BCMA and will be advancing to the clinical phase in 2019., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

The following surgical technique is intended for patients with chronic valgus laxity and rotational knee instability. It is a percutaneous 2-bundle ligament reconstruction method that uses the semitendinosus tendon, allowing it to remain pedicled to its distal tibial insertion. The aim is to correct the laxity without otherwise limiting the motion of the knee.

Injuries to stabilizing elements on the medial side of the knee are one of the most common knee ailments. Because of the good healing capacity of these structures, acute injuries are typically treated conservatively. However, valgus laxity near full extension can persist in some patients. This laxity may be the source of instability due to medial joint space opening, which then requires surgical treatment. Various procedures have been described that aim to reproduce the anatomy of the medial collateral ligament (MCL) and the posterior oblique ligament (POL), which work together to stabilize the medial aspect of the knee. However, these are complex open surgical procedures, technically demanding to achieve the favorable isometry, which prevent joint contracture or recurrence of laxity. The purpose of this study was to describe a short construct that minimizes the risk of secondary loss of tension and complies with the principle of favorable anisometry. The graft is positioned in the joint opening axis, between the deep bundle of the MCL and the POL.

Interest and knowledge on the anatomy, function, and biomechanical properties of the anterolateral ligament has led to the recognition of the importance of this structure in rotational control of the knee. This article describes a technique that allows for a combined anterior cruciate ligament (ACL) and anterolateral reconstruction, using an Iliotibial band (ITB) autograft. The graft is detached from the vastus lateralis from proximal to distal, at the center portion from ITB, preserving its distal insertion on the Gerdy tubercle. Its width is 1 cm for the distal part, used for the anterolateral ligament reconstruction, and 3 cm for the proximal part. An outside-in femoral tunnel is drilled respecting both the preferred favorable isometric femoral insertion site and the femoral ACL footprint. An ACL reconstruction combined with a lateral tenodesis with a continuous ITB graft respects the anatomical and isometric rules providing superior internal rotational control of the knee in comparison with a stand-alone ACL reconstruction.

The actin-binding protein filamins (FLNs) are major organizers of the actin cytoskeleton. They control the elasticity and stiffness of the actin network and provide connections with the extracellular microenvironment by anchoring transmembrane receptors to the actin filaments. Although numerous studies have revealed the importance of FLN levels, relatively little is known about the regulation of its stability in physiological relevant settings. Here, we show that the ASB2α cullin 5-ring E3 ubiquitin ligase is highly expressed in immature dendritic cells (DCs) and is down-regulated after DC maturation. We further demonstrate that FLNs are substrates of ASB2α in immature DCs and therefore are not stably expressed in these cells, whereas they exhibit high levels of expression in mature DCs. Using ASB2 conditional knockout mice, we show that ASB2α is a critical regulator of cell spreading and podosome rosette formation in immature DCs. Furthermore, we show that ASB2(-/-) immature DCs exhibit reduced matrix-degrading function leading to defective migration. Altogether, our results point to ASB2α and FLNs as newcomers in DC biology.

Statistical shape analysis techniques have shown to be efficient tools to build population specific models of anatomical variability. Their use is commonplace as prior models for segmentation, in which case the instance from the shape model that best fits the image data is sought. In certain cases, however, it is not just the most likely instance that must be searched, but rather the whole set of shape instances that meet certain criterion. In this paper we develop a method for the assessment of specific anatomical/morphological criteria across the shape variability found in a population. The method is based on a level set segmentation approach, and used on the parametric space of the statistical shape model of the target population, solved via a multi-level narrow-band approach for computational efficiency. Based on this technique, we develop a framework for evidence-based orthopaedic implant design. To date, implants are commonly designed and validated by evaluating implant bone fitting on a limited set of cadaver bones, which not necessarily span the whole variability in the population. Based on our framework, we can virtually fit a proposed implant design to samples drawn from the statistical model, and assess which range of the population is suitable for the implant. The method highlights which patterns of bone variability are more important for implant fitting, allowing and easing implant design improvements, as to fit a maximum of the target population. Results are presented for the optimisation of implant design of proximal human tibia, used for internal fracture fixation., (Copyright (c) 2010 Elsevier B.V. All rights reserved.)

Proximal spinal muscular atrophy (SMA) results from loss of the survival motor neuron 1 (SMN1) gene, with retention of its nearly identical homolog, SMN2. There is a direct correlation between disease severity and SMN2 copy number. Mice do not have a Smn2 gene, and thus cannot naturally replicate the disorder. However, two murine models of SMA have been generated using SMN2-BAC transgenic mice bred onto a mutant Smn background. In these instances mice die shortly after birth, have variable phenotypes within the same litter, or completely correct the SMA phenotype. Both models have been imported to The Jackson Laboratory for distribution to the research community. To ensure that similar results are obtained after importation to The Jackson Laboratory to what was originally reported in the literature, we have begun a molecular and phenotypic evaluation of these mouse models. Here we report our findings for the SMA mouse model that has been deposited by the Li group from Taiwan. These mice, JAX stock number TJL-005058, are homozygous for the SMN2 transgene, Tg(SMN2)2Hung, and a targeted Smn allele that lacks exon 7, Smn1(tm1Hung). Our findings are consistent with those reported originally for this line and clarify some of the original data. In addition, we have cloned and mapped the integration site for Tg(SMN2)2Hung to Chromosome 4, and provide a simple genotyping assay that is specific to the junction fragment. Finally, based upon the survival data from our genetic crosses, we suggest that this underused SMA model may be a useful compliment or alternative to the more commonly used "delta7" SMA mouse. We provide breeding schemes in which two genotypes of mice can be generated so that 50% of the litter will be SMA-like pups while 50% will be controls., (Copyright 2009 Elsevier Inc. All rights reserved.)

The ordered series of proliferation and differentiation from hematopoietic progenitor cells is disrupted in leukemia, resulting in arrest of differentiation at immature proliferative stages. Characterizing the molecular basis of hematopoietic differentiation is therefore important for understanding and treating disease. Retinoic acid induces expression of ankyrin repeat-containing protein with a suppressor of cytokine signaling box 2 (ASB2) in acute promyelocytic leukemia cells, and ASB2 expression inhibits growth and promotes commitment, recapitulating an early step critical for differentiation. ASB2 is the specificity subunit of an E3 ubiquitin ligase complex and is proposed to exert its effects by regulating the turnover of specific proteins; however, no ASB2 substrates had been identified. Here, we report that ASB2 targets the actin-binding proteins filamin A and B for proteasomal degradation. Knockdown of endogenous ASB2 in leukemia cells delays retinoic acid-induced differentiation and filamin degradation; conversely, ASB2 expression in leukemia cells induces filamin degradation. ASB2 expression inhibits cell spreading, and this effect is recapitulated by knocking down both filamin A and filamin B. Thus, we suggest that ASB2 may regulate hematopoietic cell differentiation by modulating cell spreading and actin remodeling through targeting of filamins for degradation.

Imexon is a member of the class of 2-cyanoaziridine derivatives, which have been of interest as immunomodulators and anticancer agents since the late 1970s. For the scheduled phase I clinical trials a stable, sterile, injectable pharmaceutical dosage form containing 100 mg Imexon was required. Despite adequate solubility, its instability in aqueous media seriously hampered the pharmaceutical development of Imexon. In this study we describe the successful use of the organic solvent dimethyl sulfoxide (DMSO) as a formulation vehicle for Imexon. DMSO is shown to provide the stability required for Imexon during manufacturing and to be a suitable vehicle for lyophilisation, which was employed to gain sufficient shelf-life for the final product. The relatively low vapour pressure of DMSO, which would theoretically result in extremely slow sublimation during lyophilisation, was shown not to limit the successful lyophilisation of Imexon from DMSO at a concentration of 25 mg/mL. The lyophilisation cycle developed for Imexon resulted in residual DMSO contents of 4.6 +/- 0.6% in the lyophilised product, limiting the amount of DMSO administered to the patient to well below the 50 mg/day acceptable in pharmaceutical products as stated in ICH guidelines. Imexon 100 mg/vial lyophilised product was shown stable for at least 12 months of storage at -20 degrees C and +5 +/- 3 degrees C in the dark., (Copyright 2005 Wiley-Liss, Inc)

Retinoic acid induces clinical remission in acute promyelocytic leukemia (APL) by triggering differentiation of leukemia promyelocytes. Here, we have characterized a gene encoding a member of the immunoglobulin superfamily, among novel retinoic acid-induced genes identified in APL cells. This protein, which was named JAML (junctional adhesion molecule-like), contains 2 extracellular immunoglobulin-like domains, a transmembrane segment, and a cytoplasmic tail. JAML mRNA is expressed in hematopoietic tissues and is prominently expressed in granulocytes. The fact that JAML protein is localized at the cell plasma membrane in the areas of cell-cell contacts, whereas it is not detected at free cell borders, suggests that JAML is engaged in homophilic interactions. Furthermore, a conserved dimerization motif among JAM members was shown to be important for JAML localization at the cell membrane. Finally, exogenous expression of JAML in myeloid leukemia cells resulted in enhanced cell adhesion to endothelial cells. Altogether, our results point to JAML as a novel member of the JAM family expressed on leukocytes with a possible role in leukocyte transmigration.

Purpose: The purpose of this study was to evaluate and compare the deltoid to triceps and biceps to triceps transfers for restoration of elbow extension in young persons with tetraplegia., Methods: This was a prospective randomized study. Sixteen arms of 9 subjects between 8 and 20 years of age with cervical-level spinal cord injuries were assigned randomly to undergo either a deltoid to triceps transfer or a biceps to triceps transfer. All arms were followed-up prospectively for at least 2 years after surgery., Results: Elbow extension was restored in 8 arms via the deltoid and in 8 arms via the biceps transfers. At the 24-month follow-up evaluation 7 of the 8 biceps transfers produced antigravity strength (grade 3 or better); in contrast only one arm with the deltoid transfer was able to extend against gravity. There was a considerable but subclinical loss (no subject appreciated any functional deficit) of elbow flexion torque after both transfers. Three months after surgery the deltoid group showed a 51% loss of elbow flexion torque and the biceps group showed a 52% loss of elbow flexion torque. By 24 months after surgery both groups improved but still showed a loss of flexion torque (deltoid 32%, biceps 47%). After gaining elbow extension the subjects in both groups rated the performance of most activities of daily living (ADL) and all self-selected activities as better, as measured on the Modified University of Minnesota Tendon Transfer Functional Improvement Questionnaire and the Canadian Occupational Performance Measure, respectively. Likewise all subjects were more satisfied with performance of their goals after undergoing elbow extension reconstruction., Conclusions: This study showed the benefits of restoring elbow extension in persons with tetraplegia and provided support for the biceps transfer as an alternative to the deltoid to triceps transfer in individuals with good brachialis and supinator strength.

Relative quiescence is a defining characteristic of hematopoietic stem cells. Reasoning that inhibitory tone dominates control of stem cell cycling, we previously showed that mice engineered to be deficient in the cyclin-dependent kinase inhibitor, p21Cip1/Waf1 (p21), have an increased stem cell pool under homeostatic conditions. Since p21 was necessary to maintain stem cell quiescence and its absence sufficient to permit increased murine stem cell cycling, we tested whether reduction of p21 alone in human adult-derived stem cells could affect stem cell proliferation. We demonstrate here that interrupting p21 expression ex vivo resulted in expanded stem cell number and in vivo stem cell function compared with control, manipulated cells. Further, we demonstrate full multilineage reconstitution capability in cells where p21 expression was knocked down. Therefore, lifting the brake on cell proliferation by altering cell cycle checkpoints provides an alternative paradigm for increasing hematopoietic stem cell numbers. This approach may be useful for relative ex vivo human stem cell expansion.

Activated cell-mediated immunity is known to be accompanied by elevated concentrations of 7,8-dihydroneopterin which in high concentrations was found to interfere with the oxidant-antioxidant balance. In this study we investigated whether 7,8-dihydroneopterin mediates apoptosis of Jurkat T-lymphocytes via a CrmA- or Bcl-2-sensitive pathway. Transient transfection assays with CrmA and Bcl-2 expression constructs showed that apoptosis was not affected by CrmA whereas it was significantly decreased upon cotransfection with Bcl-2 constructs. Results suggest that 7,8-dihydroneopterin-induced apoptosis of T-lymphocytes is mediated by a Bcl-2-sensitive pathway.

A pivotal role has been assigned to Myb in the control of myeloid cell growth. Although Myb is a target of retinoic acid, little is known about the mechanisms by which it may contribute to induced growth arrest in leukemia cells. Indeed, few Myb target genes are known to be linked to proliferation. Myeloblastin is involved in the control of proliferation in myeloid leukemia cells. It is expressed early during hematopoiesis and is a granulocyte colony-stimulating factor-responsive gene. Myeloblastin can confer factor-independent growth to hematopoietic cells, an early step in leukemia transformation. The myeloblastin promoter contains PU.1, C/EBP, and Myb binding sites, each of which are critical for constitutive expression in myeloid cells. Inhibition of myeloblastin expression in leukemia cells growth-arrested by retinoic acid is demonstrated to depend on Myb down-regulation. Myb is shown to induce myeloblastin expression and abolish its down-regulation by retinoic acid. Altogether, the data offer a clue as to how a myeloid-specific transcriptional machinery can be accessible to regulation by retinoic acid and point to myeloblastin as a novel target of Myb. This link between Myb and myeloblastin suggests a previously nonidentified Myb pathway through which growth arrest is induced by retinoic acid in myeloid leukemia cells.

Background: We hypothesize that post-pump syndrome (PPS) following cardiopulmonary bypass (CPB) can be caused by multiple minor insults and that the mechanism of PPS is a priming and subsequent activation of polymorphonuclear (PMN) leukocytes. In this study extensive pathophysiologic and morphometric assessment was undertaken in a porcine model of sequential insult PPS., Methods: Pigs were anesthetized, placed on a ventilator, instrumented for measurements of hemodynamic function, and separated into five groups: (1) Control (n = 4)--surgery only, (2) CPB (n = 4)--placed on femoral-femoral hypothermic (28 degrees C) bypass for 1 h, (3) LPS (n = 6)--underwent sham CPB followed by infusion of low dose endotoxin [E. coli lipopolysaccharide (LPS-1 microg/kg)], (4) Heparin + protamine + LPS (HP + LPS, n = 4)--were heparinized without CPB for 1 h, following which protamine and LPS were infused and (5) CPB + LPS (n = 8)--subjected to both CPB and LPS., Results: Only CPB + LPS resulted in acute respiratory distress typical of PPS as indicated by a significant decrease in PaO2 and increase in intrapulmonary shunt fraction (p<0.05). CPB + LPS significantly increased tissue density and the number of sequestered monocytes and PMNs (p<0.05) above all other groups. Alveolar macrophages (AM) increased equally in all groups receiving LPS., Conclusions: CPB primes the inflammatory system causing pulmonary PMN sequestration without lung injury. Exposure to an otherwise benign dose of endotoxin results in activation of the sequestered PMNs causing PPS. This study confirms that PPS can be caused by multiple minor insults.

The polycyclic aromatic hydrocarbon (PAH), methylcholanthrene (MCA), is a well studied carcinogen and a teratogen. MCA and other PAH cause immune suppression of B cell and T cell responses in mice and MCA had been reported to induce thymus atrophy. Here we show that MCA treatment causes thymus atrophy in adrenalectomized mice and in C57BL/6 and DBA/2 mice which differ in aryl hydrocarbon receptor (AhR) expression. This indicates that MCA-mediated thymus atrophy is mediated, at least in part, by glucocorticoid hormone receptor- and aryl hydrocarbon receptor-independent mechanisms. Assay of thymocytes, both in situ and ex vivo, demonstrate that MCA induces thymocyte apoptosis. Apoptotic thymocytes can be found within or adjacent to thymic Mphi, suggesting rapid phagocytosis. Mice that are deficient in tumor necrosis factor-alpha receptor-1 or p53, or that overexpress bcl-2 are susceptible to MCA-mediated thymus atrophy.

Histologic examination of the human myocardium has been performed several days, weeks, and months after transmyocardial laser revascularization. We performed microscopic examinations 2 hours postoperatively. In addition to the patent channel (diameter, 1 mm) and a 1-to 2-mm rim of necrosis, a 1- to 3-mm zone of myofibrillary degeneration was found. This additional reversible injury immediately after transmyocardial laser revascularization could explain the higher mortality rate in patients with reduced left ventricular function.

We describe a modified denaturing gradient gel electrophoresis (DGGE) procedure with a 40-nucleotide GC clamp in the polymerase chain reaction to improve resolution in amplifying T cell receptor-gamma (TCR-gamma) rearrangements. DNA from 46 cases of lymphoblastic leukemia/lymphoma, 5T cell lines, 2 B cell lines, 7 normal lymphocytes, and 3 cases of Hodgkin's disease was amplified by polymerase chain reaction. In addition, 20 cases of paraffin-embedded T cell lymphomas and 5 cases of reactive hyperplasia were also studied. Clonal TCR-gamma rearrangements were identified on DGGE by the presence of a predominant band. Results obtained from 5 T cell lines and 12 lymphoblastic leukemia/lymphomas containing known TCR-gamma gene rearrangements revealed 100% concordance in detecting clonal rearrangements between DGGE and traditional Southern blot analysis. Of the remaining 34 lymphoblastic leukemia/lymphoma cases studied by DGGE alone, 30 were positive. DGGE analysis of 10 lymphoblastic leukemia/lymphoma cases with known group IV gamma to J gamma 1 or J gamma 2 rearrangement sequences confirmed that the electrophoretic migration was dependent on the tumor-specific rearranged TCR-gamma sequence. In addition, 17 of 20 cases of paraffin-embedded T cell lymphomas were positive by DGGE, 6 of which had the clonal population also identified in fresh tissue DNA. DGGE analysis of GC-clamped polymerase chain reaction products can provide a way to more accurately detect TCR-gamma clonality of lymphoid tumors and can be applied to archival tissues.

Analysis of breath sounds using the stethoscope is a major part of physicians evaluation of their patients. However, the use of a stethoscope is often inadequate to give quantitative measurements of the clinical state of the individual. In this study a modification of a previously described computer analysis of breath sounds was used to measure sound intensity levels in both normal and asthmatic children who, in most cases, were unable to perform pulmonary function. The intensity levels were derived using a microcomputer-based program that digitizes audio signals and calculates energy values at 25-ms intervals throughout each signal. There were statistical differences between mean intensity levels for normal breath sounds in children between 2 and 6 years and the mean intensity levels for wheezing sounds in the same age group, as well as wheezing sounds in asthmatic patients over the age of 8 years (P less than 0.002). Also, the mean intensity levels for normal breath sounds could be clearly differentiated from intensity levels for other sounds from the chest, including heart sounds and voice sounds. Thus, computer digitized airway phonopneumography (CDAP) proved to be a reproducible, quantifiable method for demonstrating airway obstruction in those children and patients unable to perform pulmonary function testing.