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The effect of buffer species on biomolecules and biomolecule-nanoparticle interactions is a phenomenon that has been either neglected, or not understood. Here, we study the formation of a BSA protein corona (PC) around amino-functionalized mesoporous silica nanoparticles (MSN-NH 2 ) in the presence of different buffers (Tris, BES, cacodylate, phosphate, and citrate) at the same pH (7.15) and different concentrations (10, 50, and 100 mM). We find that BSA adsorption is buffer specific, with the adsorbed amount of BSA being 4.4 times higher in the presence of 100 mM Tris (184 ± 3 mg/g) than for 100 mM citrate (42 ± 2 mg/g). That is a considerable difference that cannot be explained by conventional theories. The results become clearer if the interaction energies between BSA and MSN-NH 2 , considering the electric double layer (E EDL ) and the van der Waals (E vdW ) terms, are evaluated. The buffer specific PC derives from buffer specific zeta potentials that, for MSN-NH 2 , are positive with Tris and negative with citrate buffers. A reversed sign of zeta potentials can be obtained by considering polarizability-dependent dispersion forces acting together with electrostatics to give the buffer specific outcome. These results are relevant not only to our understanding of the formation of the PC but may also apply to other bio- and nanosystems in biological media., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

In this work, the effect of incorporating silk fibroin, a fibrous biocompatible protein, into physically cross-linked agarose hydrogels was investigated as a simple model study to examine how supramolecular fibrous structures influence the properties of the hydrogels. The rheological and transport properties were studied. Fibroin did not change the general viscoelastic properties of the investigated hydrogels but changed the viscoelastic moduli values and also the mesh size, as calculated from rheometry data. Fibroin influenced the mechanical properties depending on its concentration: at lower concentrations, it increased the mesh size, while at higher concentrations, it acted as a filler, decreasing the mesh size. Similarly, the storage and loss moduli were affected, either increasing or decreasing based on the fibroin concentration. The fibroin effect on the diffusion of two dyes differing in their charge was the result of a combination of structural effects, responsible also for changes in the rheological properties, and a result of electrostatic interactions between the charged groups. For positively charged methylene blue, low fibroin concentrations accelerated diffusion, while higher concentrations slowed it by filling network vacancies. In contrast, for negatively charged eosin-B, fibroin strongly impeded diffusion at all concentrations due to electrostatic repulsion, leading to its accumulation at the hydrogel interface. The findings of this work may contribute to an understanding of the behavior of the extracellular matrix or soft tissues as well as to the development of the tailored design of hydrogel materials.

Acute pericarditis is a serious and potentially fatal disease in which a diagnostic workup is not always straightforward. Hiatal hernia, on the other hand, is often asymptomatic and can be easily diagnosed if symptomatic. In advanced forms of hiatal hernia, oppression of intrathoracic organs and heart failure can occur. In uncommon cases, the large intestine can also be translocated into the chest cavity, and very rarely, it can be perforated with the development of mediastinitis and/or pericarditis. We report the case of a 74-year-old female with a 1.5-month history of chest pain with elevated inflammatory markers. This patient was empirically treated with antibiotics for suspected pneumonia. After a few weeks, due to a worsening of the patient's condition, an echocardiogram and then a CT of the chest were performed, showing a large hiatal hernia and a very probable purulent pericarditis, necessitating a surgical exploration. A cardiac surgeon found stercoral contents in the pericardium, with a fistula at the apex of the heart. The operation continued with an exploration of the abdominal cavity; the general surgeon returned the massive hiatal hernia to the abdomen, the contents of which were the stomach and transverse colon. An extensive perforation in the transverse colon was found. Lavage, drainage, and resection of the affected part of the intestine were performed, and a permanent (terminal) colostomy was constructed. The patient was in severe septic shock with multiorgan failure and died 10 hours after surgery despite maximal therapy. This case highlights the importance of interdisciplinary cooperation and the importance of considering the possible fistula in the co-occurrence of hiatal hernia and pericarditis., Competing Interests: Human subjects: Consent was obtained or waived by all participants in this study. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Branny et al.)

Desmoplastic small round cell tumor is a very rare soft tissue sarcoma with a bleak prognosis and short patient survival. The most common occurrence is in 20-30-year-old men. Our study presents the case report of a 40-year-old patient who was diagnosed with this sarcoma. The first symptom of the illness was an incarcerated epigastric hernia with sarcoma metastasis resembling an intestinal loop in an ultrasound image. The fluorescence in situ hybridization (FISH) method showed a fusion of the EWS and WT1 genes. Systemic palliative chemotherapy using the VDC-IE (vincristine, doxorubicin, cyclophosphamide, ifosfamide, and etoposide) regimen was chosen instead of further surgery due to the disease's generalization. However, the therapy failed to halt the disease progression and was thus terminated after 18 months. The patient's overall survival was 19 months. The rare character of this disease complicates the diagnostics in clinical practice. Nevertheless, rare sarcomas should be considered in patients with non-specific abdominal symptoms, including patients with incarcerated ventral hernia., Competing Interests: Human subjects: Consent was obtained or waived by all participants in this study. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Pekař et al.)

Sarcopenia is a serious systemic disease that reduces overall survival. TAVI is selectively performed in patients with severe aortic stenosis who are not indicated for open cardiac surgery due to severe polymorbidity. Artificial intelligence-assisted body composition assessment from available CT scans appears to be a simple tool to stratify these patients into low and high risk based on future estimates of all-cause mortality. Within our study, the segmentation of preprocedural CT scans at the level of the lumbar third vertebra in patients undergoing TAVI was performed using a neural network (AutoMATiCA). The obtained parameters (area and density of skeletal muscles and intramuscular, visceral, and subcutaneous adipose tissue) were analyzed using Cox univariate and multivariable models for continuous and categorical variables to assess the relation of selected variables with all-cause mortality. 866 patients were included (median(interquartile range)): age 79.7 (74.9-83.3) years; BMI 28.9 (25.9-32.6) kg/m 2 . Survival analysis was performed on all automatically obtained parameters of muscle and fat density and area. Skeletal muscle index (SMI in cm 2 /m 2 ), visceral (VAT in HU) and subcutaneous adipose tissue (SAT in HU) density predicted the all-cause mortality in patients after TAVI expressed as hazard ratio (HR) with 95% confidence interval (CI): SMI HR 0.986, 95% CI (0.975-0.996); VAT 1.015 (1.002-1.028) and SAT 1.014 (1.004-1.023), all p < 0.05. Automatic body composition assessment can estimate higher all-cause mortality risk in patients after TAVI, which may be useful in preoperative clinical reasoning and stratification of patients., (© 2024. The Author(s).)

Desmoplastic small round cell tumor belongs to a group of soft tissue sarcomas. It is a rare disease, since its discovery in 1989, only hundreds of cases have been described in the literature. Due to the rare incidence of the tumor, this disease remains unknown in common medical practice. It occurs most often in men at young age. Its prognosis is serious and the average survival of patients ranges from 1.5 to 2.5 years. Treatment options include surgical resection, chemo-, radio- and targeted therapy. Our work presents a case report of a 40 year-old patient sufferred from this sarcoma. The first manifestation of the disease was an incarcerated epigastric hernia with omentum and sarcoma metastasis. A resection of the incarcerated part of the omentum was performed with a biopsy from another intra-abdominal lesion. Biopsy specimens were sent for histopathological evaluation. For the generalization of the disease, further surgery was not indicated and systemic palliative chemotherapy in the VDC-IE regimen was chosen. At the time of submitting the manuscript, the patient has survived 6 months since the surgical procedure.

Hyaluronic acid, a naturally occurring carbohydrate biopolymer in human tissues, finds wide application in cosmetics, medicine, and material science. Its anionic properties play a crucial role in its interaction with positively charged macromolecules and ions. Among these macromolecules, positively charged arginine molecules or polyarginine peptides demonstrate potential in drug delivery when complexed with hyaluronan. This study aimed to compare and elucidate the results of both experimental and computational investigations on the interactions between hyaluronic acid polymers and polyarginine peptides. Experimental findings revealed that by varying the length of polyarginine peptides and the molar ratio, it is possible to modulate the size, solubility, and stability of hyaluronan-arginine particles. To further explore these interactions, molecular dynamics simulations were conducted to model the complexes formed between hyaluronic acid polymers and arginine peptides. The simulations are considered in different molar ratios and lengths of polyarginine peptides. By analysis of the data, we successfully determined the shape and size of the resulting complexes. Additionally, we identified the primary driving forces behind complex formation and explained the observed variations in peptide interactions with hyaluronan.

Ten different hydrogels were prepared and analyzed from the point of view of their use in soil. FT-IR spectra, morphology, swelling ability, and rheological properties were determined for their characterization and appraisal of their stability. The aim was to characterize prepared materials containing different amounts of NPK as mineral fertilizer, lignohumate as a source of organic carbon, and its combination. This study of stability was focused on utility properties in their application in soil-repeated drying/re-swelling cycles and possible freezing in winter. Lignohumate supported the water absorbency, while the addition of NPK caused a negative effect. Pore sizes decreased with NPK addition. Lignohumate incorporated into polymers resulted in a much miscellaneous structure, rich in different pores and voids of with a wide range of sizes. NPK fertilizer supported the elastic character of prepared materials, while the addition of lignohumate shifted their rheological behavior to more liquid. Both dynamic moduli decreased in time. The most stable samples appeared to contain only one fertilizer constituent (NPK or lignohumate). Repeated re-swelling resulted in an increase in elastic character, which was connected with the gradual release of fertilizers. A similar effect was observed with samples that were frozen and defrosted, except samples containing a higher amount of NPK without lignohumate. A positive effect of acrylamide on superabsorbent properties was not confirmed.

Interactions between hyaluronan and the antimicrobial peptide cecropin B were studied in water and PBS using high-resolution ultrasonic spectroscopy and isothermal titration calorimetry. Although each technique is fundamentally different, they both gave identical results. It was found that the molecular weight of hyaluronan plays an important role in the interactions - in particular, the transition between the rod conformation and the random coil conformation. In water, interactions were saturated in a molar charge ratio of 1.5 and not 1.0 as expected. The later saturation of the interaction probably occurred either for steric reasons or due to the interaction between functional groups in the cecropin structure, which allowed complete dissociation of the antimicrobial peptide. In PBS, in contrast to water, no interactions were observed, irrespective of the molecular weight of hyaluronan. Thus, at a sufficiently high ionic strength, the interactions were suppressed., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Self-balancing diffusion is a theoretical concept that restricts the introduction of extents of reactions. This concept is analyzed in detail for general mass- and molar-based balances of reaction-diffusion mixtures, in relation to non-self-balancing cases, and with respect to its practical consequences. Self-balancing is a mathematical restriction on the divergences of diffusion fluxes. Fulfilling this condition enables the proper introduction of the extents of (independent) reactions that reduce the number of independent variables in thermodynamic descriptions. A note on a recent generalization of the concept of reaction and diffusion extents is also included. Even in the case of self-balancing diffusion, such extents do not directly replace reaction rates. Concentration changes caused by reactions (not by diffusion) are properly described by rates of independent reactions, which are instantaneous descriptors. If an overall descriptor is needed, the traditional extents of reactions can be used, bearing in mind that they include diffusion-caused changes. On the other hand, rates of independent reactions integrated with respect to time provide another overall, but reaction-only-related descriptor.

Interactions of hyaluronan with micelles formed by cationic surfactants were studied by the time-resolved measurement of fluorescence resonance energy transfer (FRET) using perylene and fluorescein as probes. Two surfactants were studied - Cetyltrimethylammonium bromide (CTAB) and Septonex. In pure micellar solutions, the same values of FRET efficiency were found for both surfactants, but values for the binding of the probe pair were lower for Septonex micelles than in the case of CTAB. This was attributed to steric effects of the carbethoxy group in the Septonex polar head. Upon the addition of hyaluronan, decreased FRET efficiency and increased binding were detected in comparison with pure surfactants. To resolve the structure of the formed aggregates, steady state and time-resolved fluorescence anisotropy was employed as an additional technique. All results indicated that cationic micelles bind to hyaluronan forming a pearl necklace structure with micelles of smaller size compared to pure surfactant. Besides theoretical interest, the studied polyelectrolyte-surfactant system may be interesting for the formulation of drug delivery systems., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Obesity is a well-known phenomenon of recent times in adult and pediatric population, as well. It has been proved, that numerous comorbidities are in a different way connected with obesity. Conservative treatment of obesity is the domain of obesitologists, diabetologists, nutritionists and psychologists, as well. Great part of the conservative treatment of obesity lies on the experts on physical activities. Surgical treatment is dedicated to the patients with severe obesity. It is targeted not only at the weight reduction, but also, or at first, at the impact on comorbidities. There are standard procedures defined and they represent substantial part of performed procedures. Novel surgical and endoscopic procedures are introduced into the practice. There are many of them. So far neither of these procedures achieve comparable effectivity and durability with standard procedures in a long-time horizon. The aim of this paper is to present standard surgical procedures, to mention novel ones, surgical and endoscopic, as well. The procedures are presented with respect to the pediatric population too.

In this work, hydrogels formed by interaction of biopolymeric electrolytes and oppositely charged surfactants are studied from the point of view of their ability to incorporate model hydrophobic dyes in their micelle-like structure. Two types of hydrogels were investigated. The first type was based on cationized dextran cross-linked by sodium dodecylsulphate. The second type was prepared by interactions of hyaluronan with carbethoxypendecinium bromide (septonex). Nile red and Atto488 were used as model dyes for the diffusion experiments. The dyes were dissolved in two different media: surfactant and physiological saline. The diffusion of dyes into hydrogel was monitored over time. Effective diffusion coefficients were determined. It was found that their values are strongly influenced by the hydrogel character, the types of dye used and the solvent. The obtained effective coefficients were higher in comparison with the values determined for the diffusion in the opposite direction (release from the hydrogel). The dyes are presented as free in physiological saline and in the form of micelles or micelle aggregates in surfactants. During diffusion into the hydrogel, they can be gradually incorporated in a "pearl necklace structure" which suppresses their mobility. In contrast, this partial immobilization of dyes can increase the concentration gradient which is a driving force of diffusion. Also, the gradual incorporation of dyes into hydrogel structures influences the values of the effective diffusion coefficients., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Introduction: Bariatric-metabolic surgery is an effective tool in the treatment of severe obesity and related diseases. Its importance has increased even more in the era of the type II diabetes mellitus and COVID 19 pandemics. The aim of our study is to present the initial results of a new operation that minimizes surgical trauma., Methods: In the prospective study, laparoscopic side-to-side anisoperistaltic jejunocolic anastomosis was constructed in order to derive part of the chyme by the anastomosis. Patients were operated in the period of IV/2018VII/2019; their mean age was 48.43±10.36 years, mean weight 112.3±16.6 kg and mean BMI 41.9±5.2. Patients were examined one month before surgery and then followed at 3, 6 and 12 months after surgery. We evaluated weight loss and changes in carbohydrate metabolism., Results: We did not record any perioperative or postoperative surgical complications. There was a statistically significant weight loss during the study period. There was a significant decrease in absolute weight in kilograms (p.

High-resolution ultrasound spectroscopy (HR-US), size and ζ-potential titrations, and isothermal titration calorimetry (ITC) were used to characterize the interactions between hyaluronan and catanionic ion pair amphiphile vesicles composed of hexadecyltrimethylammonium-dodecylsulphate (HTMA-DS), dioctadecyldimethylammonium chloride (DODAC), and cholesterol. In addition to these methods, visual observations were performed with the selected molecular weight of hyaluronan. A very good correlation was obtained between data from size titration, HR-US, and visual observation, which indicated in lower charge ratios the formation of hyaluronan-coated vesicles. On the contrary, at higher charge ratios, coated vesicles disintegrated to a size of around 2000 nm. The intensity of these interactions and the disaggregation were dependent on the molecular weight of hyaluronan. All interactions studied by ITC showed strong exothermic behavior, and these interactions between vesicles and hyaluronan were confirmed from the first addition, independently of the molecular weight of hyaluronan.