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1.
Small ; 19(39): e2302617, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37264519

RESUMEN

To ensure the safety and performance of lithium-ion batteries (LIBs), a rational design and optimization of suitable cathode materials are crucial. Lithium nickel cobalt manganese oxides (NCM) represent one of the most popular cathode materials for commercial LIBs. However, they are limited by several critical issues, such as transition metal dissolution, formation of an unstable cathode-electrolyte interphase (CEI) layer, chemical instability upon air exposure, and mechanical instability. In this work, coating fabricated by self-assembly of osmotically delaminated sodium fluorohectorite (Hec) nanosheets onto NCM (Hec-NCM) in a simple and technically benign aqueous wet-coating process is reported first. Complete wrapping of NCM by high aspect ratio (>10 000) nanosheets is enabled through an electrostatic attraction between Hec nanosheets and NCM as well as by the superior mechanical flexibility of Hec nanosheets. The coating significantly suppresses mechanical degradation while forming a multi-functional CEI layer. Consequently, Hec-NCM delivers outstanding capacity retention for 300 cycles. Furthermore, due to the exceptional gas barrier properties of the few-layer Hec-coating, the electrochemical performance of Hec-NCM is maintained even after 6 months of exposure to the ambient atmosphere. These findings suggest a new direction of significantly improving the long-term stability and activity of cathode materials by creating an artificial CEI layer.

2.
Ann Rheum Dis ; 82(9): 1142-1152, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37344156

RESUMEN

INTRODUCTION: Structural reorganisation of the synovium with expansion of fibroblast-like synoviocytes (FLS) and influx of immune cells is a hallmark of rheumatoid arthritis (RA). Activated FLS are increasingly recognised as a critical component driving synovial tissue remodelling by interacting with immune cells resulting in distinct synovial pathotypes of RA. METHODS: Automated high-content fluorescence microscopy of co-cultured cytokine-activated FLS and autologous peripheral CD4+ T cells from patients with RA was established to quantify cell-cell interactions. Phenotypic profiling of cytokine-treated FLS and co-cultured T cells was done by flow cytometry and RNA-Seq, which were integrated with publicly available transcriptomic data from patients with different histological synovial pathotypes. Computational prediction and knock-down experiments were performed in FLS to identify adhesion molecules for cell-cell interaction. RESULTS: Cytokine stimulation, especially with TNF-α, led to enhanced FLS-T cell interaction resulting in cell-cell contact-dependent activation, proliferation and differentiation of T cells. Signatures of cytokine-activated FLS were significantly enriched in RA synovial tissues defined as lymphoid-rich or leucocyte-rich pathotypes, with the most prominent effects for TNF-α. FLS cytokine signatures correlated with the number of infiltrating CD4+ T cells in synovial tissue of patients with RA. Ligand-receptor pair interaction analysis identified ICAM1 on FLS as an important mediator in TNF-mediated FLS-T cell interaction. Both, ICAM1 and its receptors were overexpressed in TNF-treated FLS and co-cultured T cells. Knock-down of ICAM1 in FLS resulted in reduced TNF-mediated FLS-T cell interaction. CONCLUSION: Our study highlights the role of cytokine-activated FLS in orchestrating inflammation-associated synovial pathotypes providing novel insights into disease mechanisms of RA.


Asunto(s)
Artritis Reumatoide , Sinoviocitos , Humanos , Citocinas , Factor de Necrosis Tumoral alfa/farmacología , Membrana Sinovial/patología , Sinoviocitos/patología , Fibroblastos/patología , Células Cultivadas
3.
World J Surg Oncol ; 21(1): 4, 2023 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-36624456

RESUMEN

BACKGROUND: It is known that specimen collection followed by histopathological workup is the core of evidence-based medical therapy of musculoskeletal tumors. There exist many controversies about how a biopsy should be performed. While some centers recommend minimal invasive biopsy procedures, mostly the core needle biopsy (CNB), others prefer the incisional biopsy. PURPOSE OF THE STUDY: This study aimed to determine the accuracy of incisional biopsy for malignant tumors in the musculoskeletal system. Moreover, advantages and disadvantages to other biopsy methods are discussed. METHODS: This retrospective, single-center study about 844 incisional biopsies (benign and malignant) analysis the diagnostic accuracy of 332 malignant tumors, concerning the final histopathological result. In addition, surgical complications are analyzed to find the best way to plan and treat patients timely and correct. Secondary endpoints are the patients age, the pure operation time, as well as the type of tumor, and the subsequent therapy. RESULTS: In summary, incisional biopsy corresponded a sensitivity of 100% for malignancy in 844 incisional biopsies and a specificity of 97.6% in 332 malignant tumors, but it features greater operative expense (incision/suture 23.5 min) and the risk of general anesthesia. CONCLUSION: The method of biopsy should be tailored to the individual patient and the experience of the center performing the procedure.


Asunto(s)
Sistema Musculoesquelético , Neoplasias de los Tejidos Blandos , Humanos , Estudios Retrospectivos , Neoplasias de los Tejidos Blandos/patología , Biopsia/métodos , Sistema Musculoesquelético/patología , Biopsia con Aguja Gruesa , Sensibilidad y Especificidad
4.
Arch Orthop Trauma Surg ; 143(2): 967-975, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35344064

RESUMEN

INTRODUCTION: Arthroscopic reconstruction techniques of the posterolateral corner (PLC) of the knee have been developed in recent years. Reconstruction techniques for higher-grade PLC injuries have not yet been validated in clinical studies. This study aimed to compare clinical outcomes of two different techniques and to present results of the first prospective randomized clinical trial of patients to undergo these novel procedures. MATERIALS AND METHODS: 19 patients with Fanelli Type B posterolateral corner injuries and additional posterior cruciate ligament ruptures were included in this prospective study. They were randomly assigned to one of two novel arthroscopic reconstruction techniques, based on open surgeries developed by Arciero (group A) and LaPrade (group B). Follow-up was conducted at 6 and 12 months postoperatively and included clinical examinations for lateral, rotational and posterior stability, range of motion and subjective clinical outcome scores (IKDC Subjective Score, Lysholm Score, Tegner Activity Scale and Numeric Rating Scale for pain). RESULTS: At 6 and 12 months postoperative, all patients in both groups presented stable to varus, external rotational and posterior forces, there were no significant differences between the two groups. At 12-month follow-up, group A patients showed significantly higher maximum flexion angles (134.17° ± 3.76° vs. 126.60° ± 4.22°; p = 0.021) compared to patients of group B. Duration of surgery was significantly longer in Group B patients than in group A (121.88 ± 11.63 vs. 165.00 ± 35.65 min; p = 0.003). Posterior drawer (side-to-side difference) remained more reduced in group A (2.50 ± 0.69 mm vs. 3.27 ± 0.92 mm; p = 0.184). Subjective patient outcome scores showed no significant differences between groups (Lysholm Score 83.33 ± 7.79 vs. 86.40 ± 9.21; p = 0.621). CONCLUSIONS: This study indicates sufficient restoration of posterolateral rotational instability, varus instability and posterior drawer after arthroscopic posterolateral corner reconstruction without neurovascular complications. Increased postoperative range of motion and a shorter and less invasive surgical procedure could favor the arthroscopic reconstruction technique according to Arciero over LaPrade's technique in future treatment considerations.


Asunto(s)
Inestabilidad de la Articulación , Traumatismos de la Rodilla , Ligamento Cruzado Posterior , Humanos , Estudios Prospectivos , Ligamento Cruzado Posterior/cirugía , Articulación de la Rodilla/cirugía , Traumatismos de la Rodilla/cirugía , Escala de Puntuación de Rodilla de Lysholm , Inestabilidad de la Articulación/cirugía , Resultado del Tratamiento
5.
World J Surg Oncol ; 20(1): 184, 2022 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-35676721

RESUMEN

BACKGROUND: According to guidelines, every soft tissue tumor (STT) larger than 3 cm should be biopsied before definitive resection. Advances in magnetic resonance imaging (MRI) improve the possibility to give a provisional diagnosis of the tumor's entity. Can lipomas and atypical lipomatous tumors (ALTs) of the extremities therefore be primarily marginally resected based on interpretation of MR images without a previous biopsy?. METHODS: In this retrospective, single-center study, 240 patients with the suspicion of a lipomatous tumor in MRI and surgical treatment in our institution between 2011 and 2020 were included. MR imaging was performed before surgery. All resected specimens underwent histopathological analysis. RESULTS: The collective comprised 142 tumors that were suspected as lipoma or ALT by the radiologist and underwent primary marginal resection (PMR). One case had myxoid liposarcoma that was underestimated on MRI and needed radical follow-up resection. One-hundred forty-one patients were cured after PMR. Ninety-eight patients were biopsied initially and in 93 cases resected afterwards according to the necessary oncological margins. CONCLUSION: In our institution, PMR is performed if a lipoma or ALT is suspected on MR imaging. Our treatment method and the diagnostic algorithm are presented. Primary resection spares patients from one surgical procedure, but a slight risk for underestimation of the tumor remains.


Asunto(s)
Lipoma , Liposarcoma , Neoplasias de los Tejidos Blandos , Adulto , Biopsia , Diagnóstico Diferencial , Humanos , Lipoma/diagnóstico , Lipoma/patología , Lipoma/cirugía , Liposarcoma/cirugía , Estudios Retrospectivos , Neoplasias de los Tejidos Blandos/cirugía
6.
Arch Orthop Trauma Surg ; 142(3): 443-453, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33751186

RESUMEN

INTRODUCTION: Although open-surgical techniques for the reconstruction of the posterolateral corner (PLC) are well established, the use of arthroscopic procedures has recently increased. When compared with open surgical preparation, arthroscopic orientation in the PLC is challenging and anatomic relations may not be familiar. Nevertheless, a profound knowledge of anatomic key structures and possible structures at risk as well as technical variations of arthroscopic approaches are mandatory to allow a precise and safe surgical intervention. MATERIALS AND METHODS: In a cadaveric video demonstration, an anterolateral (AL), anteromedial (AM), posteromedial (PM) and posterolateral (PL) portal, as well as a transseptal approach (TSA) were developed. Key structures of the PLC were defined and sequentially exposed during posterolateral arthroscopy. Finally, anatomic relations of all key structures were demonstrated. RESULTS: All key structures of the PLC can be visualized during arthroscopy. Thereby, careful portal placement is crucial in order to allow an effective exposure. Two alternatives of the TSA were described, depending on the region of interest. The peroneal nerve can be visualized dorsal to the biceps femoris tendon (BT), lateral to the soleus muscle (SM) and about 3 cm distal to the fibular styloid (FS). The distal attachment of the fibular collateral ligament (FCL) can be exposed on the lateral side of the fibular head (FH). The fibular attachment of the popliteofibular ligament (PFL) is exposed at the tip of the FS. CONCLUSION: Arthroscopy of the posterolateral recessus allows full visualization of all key structures of the posterolateral corner, which provides the basis for anatomic and safe drill channel placement in PLC reconstruction. A sufficient exposure of relevant anatomic landmarks and precise portal preparation reduce the risk of iatrogenic vascular and peroneal nerve injury.


Asunto(s)
Tendones Isquiotibiales , Articulación de la Rodilla , Artroscopía , Peroné , Humanos , Articulación de la Rodilla/cirugía , Ligamentos Articulares
7.
Chemistry ; 27(68): 16930-16937, 2021 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-34138493

RESUMEN

The urge for carbon-neutral green energy conversion and storage technologies has invoked the resurgence of interest in applying brucite-type materials as low-cost oxygen evolution reaction (OER) electrocatalysts in basic media. Transition metal layered hydroxides belonging to the brucite-type structure family have been shown to display remarkable electrochemical activity. Recent studies on the earth-abundant Fe3+ containing mössbauerite and Fe3+ rich Co-Fe layered oxyhydroxide carbonates have suggested that grafted interlayer anions might play a key role in OER catalysis. To probe the effect of such interlayer anion grafting in brucite-like layered hydroxides, we report here a systematic study on the electrocatalytic performance of three distinct Ni and Co brucite-type layered structures, namely, (i) brucite-type M(OH)2 without any interlayer anions, (ii) LDHs with free interlayer anions, and (iii) hydroxynitrate salts with grafted interlayer anions. The electrochemical results indeed show that grafting has an evident impact on the electronic structure and the observed OER activity. Ni- and Co-hydroxynitrate salts with grafted anions display notably earlier formations of the electrocatalytically active species. Particularly Co-hydroxynitrate salts exhibit lower overpotentials at 10 mA cm-2 (η=0.34 V) and medium current densities of 100 mA cm-2 (η=0.40 V) compared to the corresponding brucite-type hydroxides and LDH materials.

8.
Chemistry ; 27(14): 4691-4699, 2021 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-33332670

RESUMEN

Phenylacetylene adds [Ar*GeH2 -SnAr'], [Ar*GeH2 -PbAr'] and [Ar'SnH2 -PbAr*] at rt in a regioselective and stereoselective reaction. The highest reactivity was found for the stannylene, which reacts immediately upon addition of one equivalent of alkyne. However, the plumbylenes exhibit addition to the alkyne only in reaction with an excess of phenylacetylene. The product of the germylplumbylene addition reacts with a second equivalent of alkyne and the product of a CH-activation, a dimeric lead acetylide, were isolated. In the case of the stannylplumbylene the trans-addition product was characterized as the kinetically controlled product which isomerizes at rt to yield the cis-addition product, which is stabilized by an intramolecular Sn-H-Pb interaction. NMR chemical shifts of the olefins were investigated using two- and four-component relativistic DFT calculations, as spin-orbit effects can be large. Hydride abstraction was carried out by treating [Ar'SnPhC=CHGeH2 Ar*] with the trityl salt [Ph3 C][Al(OC{CF3 })4 ] to yield a four membered ring cation.

9.
Arch Orthop Trauma Surg ; 140(12): 2003-2012, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32955608

RESUMEN

INTRODUCTION: Injuries of the posterolateral corner (PLC) of the knee lead to chronic lateral and external rotational instability and are often associated with PCL injuries. Numerous surgical techniques for repair and reconstruction of the PLC are established. Recently, several arthroscopic techniques have been published in order to address different degrees of PLC injuries through reconstruction of one or more functional structures. The purpose of this systematic review is to give an overview about arthroscopic techniques of posterolateral corner reconstructions and to evaluate their safeness. MATERIALS AND METHODS: A systematic review of the literature on arthroscopic reconstructions of the posterolateral corner of the knee according to the PRISMA guidelines was performed using PubMed MEDLINE and Web of Science Databases on June 15th, 2020. Inclusion criteria were descriptions of surgical techniques to reconstruct different aspects of the posterolateral corner either strictly arthroscopically or minimally-invasive with an arthroscopic assistance. RESULTS: Arthroscopic techniques differ with regard to the extent of reconstructed units (popliteus tendon, popliteofibular ligament, lateral collateral ligament), surgical approach (transseptal, lateral) and biomechanical results (anatomic vs. non-anatomic reconstruction, restoration of rotational instability and/or lateral instability). CONCLUSION: Different approaches to arthroscopic PLC reconstruction are presented, yet clinical results are scarce. Up to now good and excellent clinical results are reported. No major complications are reported in the literature so far.


Asunto(s)
Artroscopía/métodos , Inestabilidad de la Articulación , Traumatismos de la Rodilla/complicaciones , Articulación de la Rodilla , Procedimientos de Cirugía Plástica/métodos , Humanos , Inestabilidad de la Articulación/etiología , Inestabilidad de la Articulación/cirugía , Articulación de la Rodilla/fisiopatología , Articulación de la Rodilla/cirugía , Ligamentos Articulares/lesiones , Ligamentos Articulares/cirugía , Ligamento Cruzado Posterior/cirugía
10.
Inorg Chem ; 58(23): 15758-15768, 2019 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-31368306

RESUMEN

Terphenyltin and terphenylgermanium trihydrides were deprotonated in reaction with strong bases, such as LiMe, LDA, or KBn. In the solid state, the Li salts of the germate anion 4 and 4a exhibit a Li-Ge contact. In the Li salt of the dihydridostannate anion 6a, the Li cation is not coordinated at the tin atom instead an interaction of the Li cation with the hydride substituents was found. Evidenced by 1H-7Li-HOESY NMR spectroscopy the Li-salt of the deprotonated tin hydride 6a exhibits in toluene solution a contact between Li cation and hydride substituents, whereas in the 1H-7Li-HOESY NMR spectrum of the homologous germate salt 4a, no crosspeak between hydride and Li signals was found. The organodihydridogermate and -stannate react as nucleophiles with low-valent Group 14 electrophiles. Thus, three compounds were synthesized: Ar-Ë'-EH2-Ar (E', E = Sn, Ge; Pb, Ge; Pb, Sn; Ar = Ar', Ar*). Following an alternative synthesis Ar'SnH2PbAr* was synthesized in reaction between [(Ar*PbH)2] and [(Ar'SnH)4] generated in situ. In reaction between low-valent organotin hydride [(Ar*SnH)2] and organdihydridostannate [Ar*SnH2]- formation of distannate [Ar*2Sn2H3]- was found.

11.
Am J Physiol Renal Physiol ; 310(11): F1356-65, 2016 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-27053686

RESUMEN

Adaptive and innate immune responses contribute to hypertension and hypertensive end-organ damage. Here, we determined the role of anaphylatoxin C5a, a major inflammatory effector of the innate immune system that is generated in response to complement activation, in hypertensive end-organ damage. For this purpose, we assessed the phenotype of C5a receptor 1 (C5aR1)-deficient mice in ANG II-induced renal and cardiac injury. Expression of C5aR1 on infiltrating and resident renal as well as cardiac cells was determined using a green fluorescent protein (GFP)-C5aR1 reporter knockin mouse. Flow cytometric analysis of leukocytes isolated from the kidney of GFP-C5aR1 reporter mice showed that 28% of CD45-positive cells expressed C5aR1. Dendritic cells were identified as the major C5aR1-expressing population (88.5%) followed by macrophages and neutrophils. Using confocal microscopy, we detected C5aR1 in the kidney mainly on infiltrating cells. In the heart, only infiltrating cells stained C5aR1 positive. To evaluate the role of C5aR1 deficiency in hypertensive injury, an aggravated model of hypertension was used. Unilateral nephrectomy was performed followed by infusion of ANG II (1.5 ng·g(-1)·min(-1)) and salt in wild-type (n = 34) and C5aR1-deficient mice (n = 32). C5aR1-deficient mice exhibited less renal injury, as evidenced by significantly reduced albuminuria. In contrast, cardiac injury was accelerated with significantly increased cardiac fibrosis and heart weight in C5aR1-deficient mice after ANG II infusion. No effect was found on blood pressure. In summary, the C5a:C5aR1 axis drives end-organ damage in the kidney but protects from the development of cardiac fibrosis and hypertrophy in experimental ANG II-induced hypertension.


Asunto(s)
Presión Sanguínea/fisiología , Hipertensión/metabolismo , Riñón/patología , Miocardio/metabolismo , Receptor de Anafilatoxina C5a/metabolismo , Angiotensina II , Animales , Modelos Animales de Enfermedad , Fibrosis/metabolismo , Fibrosis/patología , Hipertensión/inducido químicamente , Hipertensión/genética , Hipertensión/patología , Riñón/metabolismo , Ratones , Ratones Noqueados , Miocardio/patología , Receptor de Anafilatoxina C5a/genética
12.
Angew Chem Int Ed Engl ; 54(13): 4087-91, 2015 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-25656569

RESUMEN

NHC adducts of the stannylene Trip2 Sn (Trip=2,4,6-triisopropylphenyl) were reacted with zero-valent Ni, Pd, and Pt precursor complexes to cleanly yield the respective metal complexes featuring a three-membered ring moiety Sn-Sn-M along with carbene transfer onto the metal and complete substitution of the starting ligands. Thus the easily accessible NHC adducts to stannylenes are shown to be valuable precursors for transition-metal complexes with an unexpected SnSn bond. The complexes have been studied by X-ray diffraction and NMR spectroscopy as well as DFT calculations. The compounds featuring the structural motif of a distannametallacycle comprised of a [(NHC)2 M(0) ] fragment and Sn2 Trip4 represent rare higher congeners of the well-known olefin complexes. DFT calculations indicate the presence of a π-type Sn-Sn interaction in these first examples for acyclic distannenes symmetrically coordinating to a zero-valent transition metal.

13.
J Knee Surg ; 36(9): 977-987, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35798341

RESUMEN

INTRODUCTION: Precise fibular tunnel placement in posterolateral corner (PLC) reconstruction is crucial in restoring rotational and lateral stability. Despite the recent progress of arthroscopic PLC reconstruction techniques, landmarks for arthroscopic fibular tunnel placement and a comparison to open tunnel placement have not yet been described. This study aimed to (1) identify reasonable soft-tissue and bony landmarks, which can be identified by either arthroscopy, fluoroscopy, or open surgery in anatomic fibular tunnel placement and (2) to compare accuracy and reliability of arthroscopic fibular tunnel placement with open surgery. MATERIALS AND METHODS: In a retrospective study, 41 magnetic resonance images (MRIs) of the knee were analyzed with emphasis on distances of an ideal anatomic fibular tunnel to 11 soft-tissue and bony landmarks. Subsequently, in eight cadaver knees, the ideal fibular tunnel was created arthroscopically and with a standard open technique from antero-latero-inferior to postero-medio-superior with a 2-mm K-wire. Positions of both tunnels were compared on postinterventional computed tomography scans. RESULTS: Based on MRI measurements, the anatomic tunnel entry should be 14.50 (±2.18) mm distal to the tip of the fibular styloid and 10.76 (±1.37) mm posterior to the anterior edge of the fibula. The anatomic fibular tunnel exit was located 12.89 (±2.35) mm below the tip of the fibular head. Arthroscopic fibular tunnel placement was reliable in all cases. Instead, in five out of the eight cases with open surgery, the fibular tunnel crossed the defined safety distance to the closest cortical edge/tibiofibular joint (distance < 8 mm). CONCLUSIONS: Reliable soft-tissue and bony landmarks of the fibular head allow arthroscopic anatomic fibular tunnel placement in PLC surgery, which shows a lower risk of tunnel malposition compared with open surgical techniques. Future studies will have to show whether clinical results of arthroscopic PLC reconstruction are in line with this study's technical results. LEVEL OF EVIDENCE: Level III.


Asunto(s)
Peroné , Articulación de la Rodilla , Humanos , Peroné/cirugía , Estudios Retrospectivos , Reproducibilidad de los Resultados , Articulación de la Rodilla/cirugía , Artroscopía
14.
IEEE Trans Vis Comput Graph ; 28(1): 562-572, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34587023

RESUMEN

We present a differentiable volume rendering solution that provides differentiability of all continuous parameters of the volume rendering process. This differentiable renderer is used to steer the parameters towards a setting with an optimal solution of a problem-specific objective function. We have tailored the approach to volume rendering by enforcing a constant memory footprint via analytic inversion of the blending functions. This makes it independent of the number of sampling steps through the volume and facilitates the consideration of small-scale changes. The approach forms the basis for automatic optimizations regarding external parameters of the rendering process and the volumetric density field itself. We demonstrate its use for automatic viewpoint selection using differentiable entropy as objective, and for optimizing a transfer function from rendered images of a given volume. Optimization of per-voxel densities is addressed in two different ways: First, we mimic inverse tomography and optimize a 3D density field from images using an absorption model. This simplification enables comparisons with algebraic reconstruction techniques and state-of-the-art differentiable path tracers. Second, we introduce a novel approach for tomographic reconstruction from images using an emission-absorption model with post-shading via an arbitrary transfer function.

15.
IEEE Trans Vis Comput Graph ; 28(7): 2654-2667, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33211659

RESUMEN

A central challenge in data visualization is to understand which data samples are required to generate an image of a data set in which the relevant information is encoded. In this article, we make a first step towards answering the question of whether an artificial neural network can predict where to sample the data with higher or lower density, by learning of correspondences between the data, the sampling patterns and the generated images. We introduce a novel neural rendering pipeline, which is trained end-to-end to generate a sparse adaptive sampling structure from a given low-resolution input image, and reconstructs a high-resolution image from the sparse set of samples. For the first time, to the best of our knowledge, we demonstrate that the selection of structures that are relevant for the final visual representation can be jointly learned together with the reconstruction of this representation from these structures. Therefore, we introduce differentiable sampling and reconstruction stages, which can leverage back-propagation based on supervised losses solely on the final image. We shed light on the adaptive sampling patterns generated by the network pipeline and analyze its use for volume visualization including isosurface and direct volume rendering.

16.
Cells ; 11(16)2022 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-36010638

RESUMEN

Autophagy is a central mechanism for maintaining cellular homeostasis in health and disease as it provides the critical energy through the breakdown and recycling of cellular components and molecules within lysosomes. One of the three types of autophagy is chaperone-mediated autophagy (CMA), a degradation pathway selective for soluble cytosolic proteins that contain a targeting motif related to KFERQ in their amino acid sequence. This motif marks them as CMA substrate and is, in the initial step of CMA, recognised by the heat shock protein 70 (Hsc70). The protein complex is then targeted to the lysosomal membrane where the interaction with the splice variant A of the lysosomal-associated membrane protein-2 (LAMP-2A) results in its unfolding and translocation into the lysosome for degradation. Altered levels of CMA have been reported in a wide range of pathologies including many cancer types that upregulate CMA as part of the pro-tumorigenic phenotype, while in aging a decline is observed and associated with a decrease of LAMP-2 expression. The potential of altering CMA to modify a physiological or pathological process has been firmly established through genetic manipulation in animals and chemical interference with this pathway. However, its use for therapeutic purposes has remained limited. Compounds used to target and modify CMA have been applied successfully to gain a better understanding of its cellular mechanisms, but they are mostly not specific, also influence other autophagic pathways and are associated with high levels of toxicity. Here, we will focus on the molecular mechanisms involved in CMA regulation as well as on potential ways to intersect them, describe modulators successfully used, their mechanism of action and therapeutic potential. Furthermore, we will discuss the potential benefits and drawbacks of CMA modulation in diseases such as cancer.


Asunto(s)
Autofagia Mediada por Chaperones , Neoplasias , Animales , Proteínas del Choque Térmico HSC70/metabolismo , Lisosomas/metabolismo , Chaperonas Moleculares/metabolismo , Neoplasias/metabolismo
17.
J Bone Oncol ; 34: 100427, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35479666

RESUMEN

Background: Surgical therapy of bone metastases is becoming increasingly important due to prolonged life expectancy and improved oncological treatment options. In a mostly palliative approach, it is necessary to identify those patients who might benefit from surgery. The shorter the remaining lifetime, the more restricted the indication and the less radical the intervention should be. The aim of this study was to evaluate the postoperative outcomes and prognostic factors for survival of patients with surgically treated bone metastases. Methods: We retrospectively included 140 patients who underwent surgery for 151 bone metastases in the extremities and pelvis at our hospital between 2010 and 2020. We examined patient demographics, surgical procedures, 30-day complications, local tumour progression, and reoperations. Survival was calculated using Kaplan-Meier analysis. Prognostic factors were investigated by univariate analysis using the log-rank test and multivariate analysis using the Cox regression hazard model. Results: In 138 patients, the median survival time was 12.3 months. The overall survival rates at one, two, three and five years were 52.3%, 37.6%, 28.0%, and 18.0%, respectively. In univariate analysis, lung cancer, renal cell carcinoma, pathological fracture, visceral metastasis and multiple bone metastases were significantly associated with prognosis. No significant influence was determined for gender, age, location of bone metastasis, type of surgical procedure and time between diagnosis of primary tumour and surgery for bone metastasis. Multivariate analysis confirmed that pathological fracture, visceral metastasis and lung cancer were negative prognostic variables in terms of survival. Within 30 days, the incidence of complications was 25.0% and mortality was 9.3%. The most common complications were urinary tract infections (5.0%), pneumonia (4.3%), and delirium (2.9%). Local tumour progression occurred in 12 patients (8.7%) and five reoperations (3.6%) were performed. There were no significant differences between patients treated with endoprosthetic replacement (n = 47) and those treated with internal fixation (n = 91) in terms of 30-day complications and mortality as well as local tumour progression. Conclusions: Survival of patients after surgery for bone metastases in the extremities or pelvis is very limited. The presence of a pathological fracture, visceral metastasis and lung cancer were independent prognostic factors for poor survival. Both internal fixation and endoprosthetic replacement achieved similar outcomes.

18.
Tomography ; 8(3): 1586-1594, 2022 06 17.
Artículo en Inglés | MEDLINE | ID: mdl-35736879

RESUMEN

Soft tissue sarcomas are malignant diseases with a complex classification and various histological subtypes, mostly clinically inconspicuous appearance, and a rare occurrence. To ensure safe patient care, the European Society of Musculoskeletal Radiology (ESSR) issued a guideline for diagnostic imaging of soft tissue tumors in adults in 2015. In this study, we investigated whether implementation of these guidelines resulted in improved MRI protocol and report quality in patients with soft tissue sarcomas in our cancer center. All cases of histologically confirmed soft tissue sarcomas that were treated at our study center from 2006 to 2018 were evaluated retrospectively. The radiological reports were examined for their compliance with the recommendations of the ESSR. Patients were divided into two groups, before and after the introduction of the 2015 ESSR guidelines. In total, 103 cases of histologically confirmed sarcomas were studied. The distribution of, age, gender, number of subjects, performing radiology, and MRI indication on both groups did not show any significant differences. Only using the required MRI sequences showed a significant improvement after the introduction of the guidelines (p = 0.048). All other criteria, especially the requirements for the report of findings, showed no improvement. The guidelines of the European Society for Musculoskeletal Radiology are not regularly followed, and their establishment did not consistently improve MRI quality in our study group. This poses a risk for incorrect or delayed diagnosis and, ultimately, therapy of soft tissue tumors. However, this study is the first of its kind and involves a limited collective. A European-wide multicenter study would be appreciated to confirm these results.


Asunto(s)
Radiología , Sarcoma , Neoplasias de los Tejidos Blandos , Adulto , Humanos , Radiografía , Estudios Retrospectivos , Sarcoma/diagnóstico por imagen , Neoplasias de los Tejidos Blandos/diagnóstico por imagen
19.
Diagnostics (Basel) ; 12(7)2022 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-35885528

RESUMEN

Appendicular soft tissue lymphoma (ASTL) is rare and is frequently misinterpreted as soft tissue sarcoma (STS). Studies investigating magnet resonance imaging (MRI) characteristics of ASTL are scarce and showed heterogenous investigation criteria and results. The purpose of this study was to systematically review clinical presentations and MRI characteristics of ASTL as described in the current literature. For that purpose, we performed a systematic literature review in compliance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Patient demographics, clinical presentation and MRI imaging characteristics of ASTL were investigated, resulting in a total of nine included studies reporting a total of 77 patients. Signal intensity of lymphoma compared to muscle tissue was mostly described as isointense (53%) or slightly hyperintense (39%) in T1-weighted images and always as hyperintense in proton-and T2-weighted images. Multicompartmental involvement was reported in 59% of cases and subcutaneous stranding in 74%. Long segmental involvement was present in 80% of investigated cases. Involvement of neurovascular structures was reported in 41% of cases and the presence of traversing vessels in 83% of patients. The presence of these findings should lead to the inclusion of ASTL in the differential diagnosis of soft tissue masses.

20.
Diagnostics (Basel) ; 12(7)2022 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-35885479

RESUMEN

Intramuscular myxomas (IMMs) are benign tumors. Evidence regarding diagnostic and therapeutic pathways is rare, and guidelines do not exist due to their low incidence. The aim of this study was a retrospective analysis at a university cancer center and the interdisciplinary re-evaluation of the individual diagnostic and therapeutic procedures. Overall, 38 patients were included in the study. IMMs occurred mostly in middle-aged women. At the time of first consultation, 57.9% had few symptoms or were asymptomatic. In 92.1% of the cases, the tumor was localized in the extremities. The lower extremity was affected in 73.7%. The average size of IMMs was 5.0 cm. The proximally located tumors in the gluteus, thighs, and upper arms were significantly larger (p = 0.02) than the distally-located tumors in the forearms and lower legs. An MRI was performed in 97.4%. Based on imaging, an IMM was suspected in 5.6% by radiologists and in 54.1% by musculoskeletal surgeons. An incision biopsy was performed in 68.4% and led in 100.0% to the right histopathological diagnosis. In total, 89.5% of IMMs were resected. Postoperative complications requiring revision occurred in 8.8%. Recurrences or degenerations of IMMs were not reported in any of these cases.

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