Selectivity of interaction of spin-labelled lipids with peripheral proteins bound to dimyristoylphosphatidylglycerol bilayers, as determined by ESR spectroscopy.

The selectivity of interaction between spin-labelled lipids and the peripheral proteins, apocytochrome c, cytochrome c, lysozyme and polylysine has been studied using ESR spectroscopy. Derivatives of phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylglycerol (PG), phosphatidylserine (PS), phosphatidylinositol (PI), diphosphatidylglycerol (CL) and diacylglycerol (DG) spin-labelled at the 5-C atom position of the sn-2 chain were used to study the association of these proteins with bilayers of dimyristoylphosphatidylglycero. Binding of the proteins increased the outer hyperfine splitting in the ESR spectra of the lipid spin labees to an extent which depended both on the spin-labelled lipid species involved and on the particular protein. The order of selectivity for apocytochrome c follows the sequence: PI−>CL−≈DG PS−>PC±>PG−>PE±. The selectivity pattern for cytochrome c is: PI−>PG−>CL−>DG PS−≈PC±>PE±; for lysozyme is: CL−>PG−>DG PE−>PC±PS−>PI−; and that for polylysine is: CL−>PS−⩾PG−>PI−>PC±>DG PE+-. The overall strength of interaction is in the order lysozyme>cytochrome c>apcoytochrome c, for equivalent binding, and the spread of the selectivity for the different proteins is in the reverse order. Assuming fast exchange for the ESR spectra of the 5-C atom labelled lipids, the relative association constants of the different labels with the different proteins have been estimated

Structural Descriptions in Human-Assisted Robot Visual Learning

The paper presents an approach to using structural descriptions, obtained through a human-robot tutoring dialogue, as labels for the visual object models a robot learns. The paper shows how structural descriptions enable relating models for different aspects of one and the same object, and how being able to relate descriptions for visual models and discourse referents enables incremental updating of model descriptions through dialogue (either robot- or human-initiated). The approach has been implemented in an integrated architecture for human-assisted robot visual learning

Salvage surgery for a giant melanoma on the back

We report a case of a giant melanoma on the back with a very extreme Breslow thickness. On physical examination a large odorous and ulcerating tumour was seen adjacent to two large crusted lesions, probably in transit metastases. In the right and left axilla enlarged lymph nodes were palpated. The patient underwent salvage surgery consisting of a complete wide excision of the tumors on the back as well as axillary lymph node dissection on both sides. Histopathology showed a malignant melanoma with a Breslow thickness of 48 mm. Four of fifteen nodes in the right axilla and one of nine nodes in the left axilla, were positive for metastatic disease. Also various in transit and subcutaneous metastases were found in the wide excision specimen. The interest of our observation relies in the rarity of a melanoma with such an extreme Breslow thickness and the difficulty in performing adequate palliative therapy that offers quality of life by means of tumor control

A Context-Dependent Model of Proximity in Physically Situated Environments

The paper presents a computational model for a context-dependent analysis of a physical environment in terms of spatial proximity. The model provides a basis for grounding linguistic analyses of spatial expressions in visual perception. The model uses potential fields to model spatial proximity. It has been implemented, and when combined with a handcrafted grammar, is used to enable a conversational robot to carry out a situated dialogue with a human. The key concept in our approach is defining the region that is proximal to a landmark based on the spatial configuration of other objects in the scene. The model extends existing approaches to proximity by including object salience (visual, discourse) and interference effects between multiple objects that could act as landmarks. Theoretically, the model can help motivate the choice between topological and projective prepositions, and provides a basis for defining regions with vague spatial extent

Active Site Mapping of Xylan-Deconstructing Enzymes with Arabinoxylan Oligosaccharides Produced by Automated Glycan Assembly

Xylan-degrading enzymes are crucial for the deconstruction of hemicellulosic biomass, making the hydrolysis products available for various industrial applications such as the production of biofuel. To determine the substrate specificities of these enzymes, we prepared a collection of complex xylan oligosaccharides by automated glycan assembly. Seven differentially protected building blocks provided the basis for the modular assembly of 2-substituted, 3-substituted, and 2-/3-substituted arabino- and glucuronoxylan oligosaccharides. Elongation of the xylan backbone relied on iterative additions of C4-fluorenylmethoxylcarbonyl (Fmoc) protected xylose building blocks to a linker-functionalized resin. Arabinofuranose and glucuronic acid residues have been selectively attached to the backbone using fully orthogonal 2-(methyl)naphthyl (Nap) and 2-(azidomethyl)benzoyl (Azmb) protecting groups at the C2 and C3 hydroxyls of the xylose building blocks. The arabinoxylan oligosaccharides are excellent tools to map the active site of glycosyl hydrolases involved in xylan deconstruction. The substrate specificities of several xylanases and arabinofuranosidases were determined by analyzing the digestion products after incubation of the oligosaccharides with glycosyl hydrolases.Fil: Senf, Deborah. Max Planck Institut für Kolloid und Grenzflächenforschung; Alemania. Freie Universität; AlemaniaFil: Ruprecht, Colin. Max Planck Institut für Kolloid und Grenzflächenforschung; AlemaniaFil: de Kruijff, Goswinus H. M.. Max Planck Institut für Kolloid und Grenzflächenforschung; Alemania. Freie Universität; Alemania. University Mainz. Institute of Institute of Organic Chemistry, Johannes Gutenberg; AlemaniaFil: Simonetti, Sebastián Osvaldo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Química Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Química Rosario; Argentina. Max Planck Institut für Kolloid und Grenzflächenforschung; AlemaniaFil: Schuhmacher, Frank. Max Planck Institut für Kolloid und Grenzflächenforschung; Alemania. Freie Universität; AlemaniaFil: Seeberger, Peter H.. Max Planck Institut für Kolloid und Grenzflächenforschung; Alemania. Freie Universität; AlemaniaFil: Pfrengle, Fabian. Max Planck Institut für Kolloid und Grenzflächenforschung; Alemania. Freie Universität; Alemani

The application of fluorescence techniques in meningioma surgery-a review

Surgical resections of meningiomas, the most common intracranial tumor in adults, can only be curative if radical resection is achieved. Potentially, the extent of resection could be improved, especially in complex and/or high-grade meningiomas by fluorescence-guided surgery using 5-aminolevulinic acid (5-ALA), indocyanine green (ICG), or fluorescein. This review aims to summarize and evaluate these fluorescence-guided meningioma surgery techniques. PubMed and Embase were searched for relevant articles. Additionally, we checked reference lists for further studies. Forty-eight articles were included in the final analysis. 5-ALA fluoresced with varying sensitivity and selectivity in meningiomas and in invaded bone and dura mater. Although ICG was mainly applied for video angiography, one report shows tumor fluorescence 18-28 h post-ICG injection. Lastly, the use of fluorescein could aid in the identification of tumor remnants; however, detection of dural tail is highly questionable. Fluorescence-guided meningioma surgery should be a reliable, highly specific, and sensitive technique. Despite numerous studies reporting the use of fluorescent dyes, currently, there is no evidence that these tools improve the radical resection rate and long-term recurrence-free outcome in meningioma surgery without neurological deficits. Evidence regarding the effectiveness and increased safety of resection after the application of these fluorophores is currently lacking. Future research should focus on the development of a meningioma-targeted, highly sensitive, and specific fluorophore

Secondary and Tertiary Hyperparathyroidism:A Narrative Review

End-stage renal disease is often complicated by the occurrence of secondary and eventually tertiary hyperparathyroidism, characterized by increased parathormone, calcium, and phosphate concentrations. Related symptoms include pruritus and osteodynia, concentration difficulties, and feelings of depression may be present. In the long-term, end-stage renal disease patients with hyperparathyroidism have an increased risk of all-cause and cardiovascular mortality. Among treatment options are vitamin D supplements, phosphate binders, calcimimetics, and surgical parathyroidectomy. Determining the optimal treatment for the individual patient is challenging for nephrologists and endocrine surgeons. This review resumes the pathogenesis of hyperparathyroidism, clinical presentation, required diagnostic work-up, and discusses indications for the available treatment options for patients with secondary and tertiary hyperparathyroidism

Focal Thyroid Incidentalomas on F-18-FDG PET/CT:A Systematic Review and Meta-Analysis on Prevalence, Risk of Malignancy and Inconclusive Fine Needle Aspiration

BackgroundThe rising demand for 18F-fluorodeoxyglucose positron emission tomography with computed tomography (18F-FDG PET/CT) has led to an increase of thyroid incidentalomas. Current guidelines are restricted in giving options to tailor diagnostics and to suit the individual patient.ObjectivesWe aimed at exploring the extent of potential overdiagnostics by performing a systematic review and meta-analysis of the literature on the prevalence, the risk of malignancy (ROM) and the risk of inconclusive FNAC (ROIF) of focal thyroid incidentalomas (FTI) on 18F-FDG PET/CT.Data SourcesA literature search in MEDLINE, Embase and Web of Science was performed to identify relevant studies.Study SelectionStudies providing information on the prevalence and/or ROM of FTI on 18F-FDG PET/CT in patients with no prior history of thyroid disease were selected by two authors independently. Sixty-one studies met the inclusion criteria.Data AnalysisA random effects meta-analysis on prevalence, ROM and ROIF with 95% confidence intervals (CIs) was performed. Heterogeneity and publication bias were tested. Risk of bias was assessed using the quality assessment of diagnostic accuracy studies (QUADAS-2) tool.Data SynthesisFifty studies were suitable for prevalence analysis. In total, 12,943 FTI were identified in 640,616 patients. The pooled prevalence was 2.22% (95% CI = 1.90% - 2.54%, I2 = 99%). 5151 FTI had cyto- or histopathology results available. The pooled ROM was 30.8% (95% CI = 28.1% - 33.4%, I2 = 57%). 1308 (83%) of malignant nodules were papillary thyroid carcinoma (PTC). The pooled ROIF was 20.8% (95% CI = 13.7% - 27.9%, I2 = 92%).LimitationsThe main limitations were the low to moderate methodological quality of the studies and the moderate to high heterogeneity of the results.ConclusionFTI are a common finding on 18F-FDG PET/CTs. Nodules are malignant in approximately one third of the cases, with the majority being PTC. Cytology results are non-diagnostic or indeterminate in one fifth of FNACs. These findings reveal the potential risk of overdiagnostics of FTI and emphasize that the workup of FTI should be performed within the context of the patient’s disease and that guidelines should adopt this patient tailored approach

Application of CO2 laser evaporation in locally advanced melanoma

Aim: This study aims to investigate the role of CO(2)laser evaporation in the treatment of melanoma patients with satellite or in-transit metastases. Materials & methods: Patients who underwent CO2 laser evaporation were retrospectively included between November 2002 and August 2018. The Sharplan 40C CO2 laser was used with a high pulse wave mode. Data concerning patient and tumor characteristics, CO2 laser evaporation and subsequent therapies were collected. Results:A total of 26patients were included. Median duration of local control was 5.5 months. The median number of lesions evaporated per treatment was three (1-16); patients received a median of three (1-19) treatments. Conclusion: In a selected group of melanoma patients with satellite or in-transit metastases, CO2 laser evaporation should be considered as treatment for local control