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In Vivo Assessment on Freeze-Cast Calcium Phosphate-Based Scaffolds with a Selective Cell/Tissue Ingrowth
(AMER CHEMICAL SOC, 2024-10-21) Mařáková, Lucie; Pejchal, Jaroslav; Roleček, Jakub; Vojníková, Michaela; Chlup, Zdeněk; Mařák, Vojtěch; González-Sánchez, Manuela; Čížková, Jana; Salamon, David
Highly porous bioceramic scaffolds are widely used as bone substitutes in many applications. However, the use of bioceramics is often limited to hard tissues due to the risk of potential soft tissue calcification. A further limitation of highly porous bioceramic scaffolds is their poor mechanical stability, manifested by their tendency to break under stress. In our study, highly porous CaP-based scaffolds were prepared via freeze-casting with longitudinal and oriented pores ranging from 10 to 20 mu m and a relative porosity of similar to 70%. The resulting scaffolds achieved a flexural strength of 10.6 +/- 2.7 MPa, which, in conjunction with their favorable bioactivity, made them suitable for in vivo testing. The prepared scaffolds were subcutaneously implanted in rats for two distinct periods: 6 weeks and 6 months, respectively. The subsequent development of fibrous tissue and involvement of myofibroblasts, newly formed vessels, and macrophages were observed, with notable changes in spatial and temporal distributions within the implantation. The absence of calcification in the surrounding soft tissue, as a result of the narrow pore geometry, indicates the opportunity to tailor the scaffold behavior for soft tissue regeneration.
The impact of single and combined amendment of elemental sulphur and graphene oxide on soil microbiome and nutrient transformation activities
(Elsevier Ltd, 2024-10-15) Hammerschmiedt, Tereza; Holátko, Jiří; Bytešníková, Zuzana; Škarpa, Petr; Richtera, Lukáš; Kintl, Antonín; Pekárková, Jana; Kučerík, Jiří; Jaskulska, Iwona; Radziemska, Maja; Valová, Radmila; Malíček, Ondřej; Brtnický, Martin
Background: Sulphur (S) deficiency has emerged in recent years in European soils due to the decreased occurrence of acid rains. Elemental sulphur (S0) is highly beneficial as a source of S in agriculture, but it must be oxidized to a plant-accessible form. Micro- or nano-formulated S0 may undergo accelerated transformation, as the oxidation rate of S0 indirectly depends on particle size. Graphene oxide (GO) is a 2D-carbon-based nanomaterial with benefits as soil amendment, which could modulate the processes of S0 oxidation. Micro-and nano-sized composites, comprised of S0 and GO, were tested as soil amendments in a pot experiment with unplanted soil to assess their effects on soil microbial biomass, activity, and transformation to sulphates. Fourteen different variants were tested, based on solely added GO, solely added micro- or nano-sized S0 (each in three different doses) and on a combination of all S0 doses with GO. Results: Compared to unamended soil, nano-S0 and nano-S0+GO increased soil pH(CaCl2). Micro-S0 (at a dose 4 g kg1) increased soil pH(CaCl2), whereas micro-S0+GO (at a dose 4 g kg1) decreased soil pH(CaCl2). The total bacterial and ammonium oxidizer microbial abundance decreased due to micro-S0 and nano-S0 amendment, with an indirect dependence on the amended dose. This trend was alleviated by the co-application of GO. Urease activity showed a distinct response to micro-S0+GO (decreased value) and nano-S0+GO amendment (increased value). Arylsulfatase was enhanced by micro-S0+GO, while sulphur reducing bacteria (dsr) increased proliferation due to high micro-S0 and nano-S0, and co-amendment of both with GO. In comparison to nano-S0, the amendment of micro-S0+GO more increased soluble sulphur content more significantly. Conclusions: Under the conditions of this soil experiment, graphene oxide exhibited a significant effect on the process of sulphur oxidation.
Exploring the Frontiers of Cell Temperature Measurement and Thermogenesis
(WILEY, 2024-10-28) Zhu, Hanliang; Xu, Haotian; Zhang, Yue; Brodský, Jan; Gablech, Imrich; Korabečná, Marie; Neužil, Pavel
The precise measurement of cell temperature and an in-depth understanding of thermogenic processes are critical in unraveling the complexities of cellular metabolism and its implications for health and disease. This review focuses on the mechanisms of local temperature generation within cells and the array of methods developed for accurate temperature assessment. The contact and noncontact techniques are introduced, including infrared thermography, fluorescence thermometry, and other innovative approaches to localized temperature measurement. The role of thermogenesis in cellular metabolism, highlighting the integral function of temperature regulation in cellular processes, environmental adaptation, and the implications of thermogenic dysregulation in diseases such as metabolic disorders and cancer are further discussed. The challenges and limitations in this field are critically analyzed while technological advancements and future directions are proposed to overcome these barriers. This review aims to provide a consolidated resource for current methodologies, stimulate discussion on the limitations and challenges, and inspire future innovations in the study of cellular thermodynamics.
Nanoformulation of the Broad-Spectrum Hydrophobic Antiviral Vacuolar ATPase Inhibitor Diphyllin in Human Recombinant H-ferritin
(Dove Press, 2024-04-30) Vojníková, Michaela; Súkupová, Martina; Štefánik, Michal; Straková, Petra; Haviernik, Jan; Kapolková, Kateřina; Gruberová, Eliška; Rašková, Klára; Michálková, Hana; Švec, Pavel; Pešková, Marie; Huvarová, Ivana; Růžek, Daniel; Salát, Jiří; Pekařík, Vladimír; Eyer, Luděk; Heger, Zbyněk
As highlighted by recent pandemic outbreaks, antiviral drugs are crucial resources in the global battle against viral diseases. Unfortunately, most antiviral drugs are characterized by a plethora of side effects and low efficiency/poor bioavailability owing to their insolubility. This also applies to the arylnaphthalide lignin family member, diphyllin (Diph). Diph acts as a vacuolar ATPase inhibitor and has been previously identified as a promising candidate with broad-spectrum antiviral activity. However, its physicochemical properties preclude its efficient administration in vivo, complicating preclinical testing.
Optimization of a silver-nanoprism conjugated with 3,3 ',5,5 '-tetramethylbenzidine towards easy-to-make colorimetric analysis of acetaldehyde: a new platform towards rapid analysis of carcinogenic agents and environmental technology
(ROYAL SOC CHEMISTRY, 2023-02-14) Farshchi, Fatemeh; Saadati, Arezoo; Hasanzadeh, Mohammad; Liu, Yu-Qian; Seidi, Farzad
Acetaldehyde acts as an important mediator in the metabolism of plants and animals; however, its abnormal level can cause problems in biological processes. Although acetaldehyde is found naturally in many organisms, exposure to high concentrations can have effects on the eyes, respiratory system, etc. Due to the importance of detecting acetaldehyde in environmental samples and biofluids, determination of its concentration is highly demanded. There are some reports showing exposure to high concentrations of acetaldehyde for a long time can increase the risk of cancer by reacting with DNA. In this work, we presented a novel colorimetric method for rapid and sensitive detection of acetaldehyde with high reproducibility using different AgNPs with various morphologies. The redox reaction between AgNPs, 3,3 ',5,5 '-tetramethylbenzidine (TMB) solution, and analytes endows a color change in 15 minutes that is detectable by the naked eye. UV spectrophotometry was further used for quantitative analysis. An iron mold with a hexagonal pattern and liquid paraffin were also used to prepare the paper-based microfluidic substrate, as a low cost, accessible, and rapid detection tool. Different types of AgNPs showed different lower limits of quantification (LLOQ). The AgNPs-Cit and AgNPrs could identify acetaldehyde with linear range of 10(-7) to 10 M and an LLOQ of 10(-7) M. The AgNWs showed the best color change activity with a linear range 10(-5) to 10 M and the lowest diagnostic limit is 10(-5) M. Finally, analysis of human biofluids as real samples were successfully performed using this system.

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