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1.
ACS Appl Mater Interfaces ; 16(31): 40483-40498, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39058959

RESUMO

Three-dimensional (3D) spheroid cell cultures of fibroblast (L929) and tumor mammary mouse (4T1) were chosen as in vitro tissue models for tissue imaging of ternary AgInS/ZnS fraction quantum dots (QDs). We showed that the tissue-mimetic morphology of cell spheroids through well-developed cell-cell and cell-matrix interactions and distinct diffusion/transport characteristics makes it possible to predict the effect of ternary AgInS/ZnS fraction QDs on the vital activity of cells while simultaneously comparing with classical two-dimensional (2D) cell cultures. The AgInS/ZnS fractions, emitting in a wide spectral range from 635 to 535 nm with a mean size from ∼3.1 ± 0.8 to ∼1.8 ± 0.4 nm and a long photoluminescence lifetime, were separated from the initial QD ensemble by using antisolvent-induced precipitation. For ternary AgInS/ZnS fraction QDs, the absence of toxicity at different QD concentrations was demonstrated on 2D and 3D cell structures. QDs show a robust correlation between numerous factors: their sizes in biological fluids over time, penetration capabilities into 2D and 3D cell structures, and selectivity with respect to penetration into cancerous and healthy cell spheroids. A reproducible protocol for the preparation of QDs along with their unique biological properties allows us to consider ternary AgInS/ZnS fraction QDs as attractive fluorescent contrast agents for tissue imaging.


Assuntos
Pontos Quânticos , Esferoides Celulares , Sulfetos , Compostos de Zinco , Pontos Quânticos/química , Pontos Quânticos/toxicidade , Animais , Camundongos , Sulfetos/química , Compostos de Zinco/química , Esferoides Celulares/efeitos dos fármacos , Linhagem Celular Tumoral , Índio/química , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Prata/química , Tamanho da Partícula , Compostos de Prata/química
2.
Biomedicines ; 12(7)2024 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-39061967

RESUMO

Conventional chemotherapeutic approaches currently used for brain tumor treatment have low efficiency in targeted drug delivery and often have non-target toxicity. Development of stable and effective drug delivery vehicles for the most incurable diseases is one of the urgent biomedical challenges. We have developed polymer nanoparticles (NPs) with improved temozolomide (TMZ) delivery for promising brain tumor therapy, performing a rational design of polyelectrolyte complexes of oppositely charged polysaccharides of cationic chitosan and anionic pectin. The NPs' diameter (30 to 330 nm) and zeta-potential (-29 to 73 mV) varied according to the initial mass ratios of the biopolymers. The evaluation of nanomechanical parameters of native NPs demonstrated changes in Young's modulus from 58 to 234 kPa and adhesion from -0.3 to -3.57 pN. Possible mechanisms of NPs' formation preliminary based on ionic interactions between ionogenic functional groups were proposed by IR spectroscopy and dynamic rheology. The study of the parameters and kinetics of TMZ sorption made it possible to identify compounds that most effectively immobilize and release the active substance in model liquids that simulate the internal environment of the body. A polyelectrolyte carrier based on an equal ratio of pectin-chitosan (0.1% by weight) was selected as the most effective for the delivery of TMZ among a series of obtained NPs, which indicates a promising approach to the treatment of brain tumors.

3.
Anal Chem ; 96(29): 12057-12064, 2024 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-38979842

RESUMO

De novo sequencing of any novel peptide/protein is a difficult task. Full sequence coverage, isomeric amino acid residues, inter- and intramolecular S-S bonds, and numerous other post-translational modifications make the investigators employ various chemical modifications, providing a variety of specific fragmentation MSn patterns. The chemical processes are time-consuming, and their yields never reach 100%, while the subsequent purification often leads to the loss of minor components of the initial peptide mixture. Here, we present the advantages of the EThcD method that enables establishing the full sequence of natural intact peptides of ranid frogs in de novo top-down mode without any chemical modifications. The method provides complete sequence coverage, including the cyclic disulfide section, and reliable identification of isomeric leucine/isoleucine residues. The proposed approach demonstrated its efficiency in the analysis of peptidomes of ranid frogs from several populations of Rana arvalis, Rana temporaria, and Pelophylax esculentus complexes.


Assuntos
Peptídeos , Ranidae , Animais , Peptídeos/química , Peptídeos/análise , Peptídeos/metabolismo , Sequência de Aminoácidos , Análise de Sequência de Proteína/métodos , Proteínas de Anfíbios/química , Proteínas de Anfíbios/metabolismo
4.
Nutrients ; 16(13)2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38999817

RESUMO

Amygdalin is purported to exhibit anti-cancer properties when hydrolyzed to hydrogen cyanide (HCN). However, knowledge about amygdalin efficacy is limited. A questionnaire evaluating the efficacy, treatment, and dosing protocols, reasons for use, HCN levels, and toxicity was distributed to physicians and healers in Germany, providing amygdalin as an anti-cancer drug. Physicians (20) and healers (18) provided amygdalin over 8 (average) years to nearly 80 annually treated patients/providers. Information about amygdalin was predominantly obtained from colleagues (55%). Amygdalin was administered both intravenously (100%) and orally (32%). Intravenous application was considered to maximally delay disease progression (90%) and relieve symptoms (55%). Dosing was based on recommendations from colleagues (71%) or personal experience (47%). If limited success became apparent after an initial 3g/infusion, infusions were increased to 27g/infusion. Treatment response was primarily monitored with established (26%) and non-established tumor markers (19%). 90% did not monitor HCN levels. Negative effects were restricted to a few dizzy spells and nausea. Only 58% were willing to participate in clinical trials or contribute data for analysis (34%). Amygdalin infusions are commonly administered by healers and physicians with few side effects. The absence of standardized treatment calls for guidelines. Since intravenous application bypasses metabolization, re-evaluation of its mode of action is required.


Assuntos
Amigdalina , Neoplasias , Amigdalina/administração & dosagem , Humanos , Neoplasias/tratamento farmacológico , Inquéritos e Questionários , Médicos , Alemanha , Feminino , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
5.
Endocr Relat Cancer ; 31(9)2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38864697

RESUMO

Pheochromocytoma (PCC) and abdominal paraganglioma (aPGL) (together abbreviated PPGL) frequently present with an underlying genetic event in a PPGL driver gene, and additional susceptibility genes are anticipated. Here, we re-analyzed whole-exome sequencing data for PCC patients and identified two patients with rare missense variants in the calcium voltage-gated channel subunit 1H gene (CACNA1H). CACNA1H variants were also found in the clinical setting in PCC patients using targeted sequencing and from analysis of The Cancer Genome Atlas database. In total, CACNA1H variants were found in six PCC cases. Three of these were constitutional, and two are known to have functional consequences on hormone production and gene expression in primary aldosteronism and aldosterone-producing adrenocortical adenoma. In general, PPGL exhibited reduced CACNA1H mRNA expression as compared to normal adrenal. Immunohistochemistry showed strong CACNA1H (CaV3.2) staining in adrenal medulla while PPGL typically had weak or negative staining. Reduced CACNA1H gene expression was especially pronounced in PCC compared to aPGL and in PPGL with cluster 2 kinase signaling phenotype. Furthermore, CACNA1H levels correlated with HIF1A and HIF2A. Moreover, TCGA data revealed a correlation between CACNA1H methylation density and gene expression. Expression of rCacna1h in PC12 cells induced differential protein expression profiles, determined by mass spectrometry, as well as a shift in the membrane potential where maximum calcium currents were observed, as determined by electrophysiology. The findings suggest the involvement of CACNA1H/CaV3.2 in pheochromocytoma development and establish a potential link between the etiology of adrenomedullary and adrenocortical tumor development.


Assuntos
Neoplasias das Glândulas Suprarrenais , Regulação para Baixo , Feocromocitoma , Feocromocitoma/genética , Feocromocitoma/metabolismo , Humanos , Neoplasias das Glândulas Suprarrenais/genética , Neoplasias das Glândulas Suprarrenais/metabolismo , Feminino , Masculino , Animais , Pessoa de Meia-Idade , Adulto , Ratos , Canais de Cálcio Tipo T/genética , Canais de Cálcio Tipo T/metabolismo , Células PC12
6.
Colloids Surf B Biointerfaces ; 241: 113994, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38850744

RESUMO

Guided bone regeneration (GBR) is a widely used procedure that prevents the fast in-growth of soft tissues into bone defect. Among the different types of membranes, the use of collagen membranes is the gold standard. However, these membranes are implanted in tissue location where a severe acute inflammation will occur and can be negatively affected. The aim of this study was to develop a collagen-based membrane for GBR that incorporated alginate-hydroxyapatite microparticles. Membranes were manufactured using collagen type I and gelatin and alginate-hydroxyapatite microparticles. Membranes were assessed in terms of topography by scanning electron microscopy and confocal microscopy; stability by swelling after an overnight incubation in saline and enzymatic degradation against collagenase and mechanical properties by tensile tests. Furthermore, the biological response was assessed with SaOs-2 cells and THP-1 macrophages to determine alkaline phosphatase activity and inflammatory cytokine release. Our results showed that the incorporation of different percentages of these microparticles could induce changes in the surface topography. When the biological response was analyzed, either membranes were not cytotoxic to THP-1 macrophages or to SaOs-2 cells and they did not induce the release of pro-inflammatory cytokines. However, the different surface topographies did not induce changes in the macrophage morphology and the release of pro- and anti-inflammatory cytokines, suggesting that the effect of surface roughness on macrophage behavior could be dependent on other factors such as substrate stiffness and composition. Collagen-gelatin membranes with embedded alginate-hydroxyapatite microparticles increased ALP activity, suggesting a positive effect of them on bone regeneration, remaining unaffected the release of pro- and anti-inflammatory cytokines.


Assuntos
Alginatos , Regeneração Óssea , Durapatita , Inflamação , Osteoblastos , Regeneração Óssea/efeitos dos fármacos , Humanos , Osteoblastos/efeitos dos fármacos , Osteoblastos/citologia , Durapatita/química , Durapatita/farmacologia , Alginatos/química , Inflamação/patologia , Propriedades de Superfície , Gelatina/química , Macrófagos/metabolismo , Regeneração Tecidual Guiada/métodos , Membranas Artificiais , Tamanho da Partícula , Citocinas/metabolismo , Colágeno Tipo I/química , Colágeno Tipo I/metabolismo , Colágeno Tipo I/farmacologia , Ácido Glucurônico/química , Ácido Glucurônico/farmacologia , Ácidos Hexurônicos/química , Ácidos Hexurônicos/farmacologia
7.
Methods Mol Biol ; 2817: 133-143, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38907152

RESUMO

Nontargeted single-cell proteomics analysis by mass spectrometry with sample multiplexing utilizing isobaric labeling is often performed using a carrier proteome. The presented protocol describes a targeted approach that replaces the carrier proteome with a set of synthetic peptides from selected proteins, which improves the identification and quantification of these proteins in single human cells.


Assuntos
Espectrometria de Massas , Proteoma , Proteômica , Análise de Célula Única , Proteômica/métodos , Análise de Célula Única/métodos , Humanos , Espectrometria de Massas/métodos , Proteoma/análise , Peptídeos/química , Peptídeos/metabolismo , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos
8.
Environ Microbiol ; 26(6): e16632, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38861374

RESUMO

This study conducted a comparative proteomic analysis to identify potential genetic markers for the biological function of chemolithoautotrophic iron oxidation in the marine bacterium Ghiorsea bivora. To date, this is the only characterized species in the class Zetaproteobacteria that is not an obligate iron-oxidizer, providing a unique opportunity to investigate differential protein expression to identify key genes involved in iron-oxidation at circumneutral pH. Over 1000 proteins were identified under both iron- and hydrogen-oxidizing conditions, with differentially expressed proteins found in both treatments. Notably, a gene cluster upregulated during iron oxidation was identified. This cluster contains genes encoding for cytochromes that share sequence similarity with the known iron-oxidase, Cyc2. Interestingly, these cytochromes, conserved in both Bacteria and Archaea, do not exhibit the typical ß-barrel structure of Cyc2. This cluster potentially encodes a biological nanowire-like transmembrane complex containing multiple redox proteins spanning the inner membrane, periplasm, outer membrane, and extracellular space. The upregulation of key genes associated with this complex during iron-oxidizing conditions was confirmed by quantitative reverse transcription-PCR. These findings were further supported by electromicrobiological methods, which demonstrated negative current production by G. bivora in a three-electrode system poised at a cathodic potential. This research provides significant insights into the biological function of chemolithoautotrophic iron oxidation.


Assuntos
Proteínas de Bactérias , Ferro , Oxirredução , Proteômica , Ferro/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Crescimento Quimioautotrófico , Família Multigênica , Regulação Bacteriana da Expressão Gênica , Água do Mar/microbiologia
9.
Neuropharmacology ; 255: 110019, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38810926

RESUMO

The endogenous opioid system has been implicated in alcohol consumption and preference in both humans and animals. The mu opioid receptor (MOR) is expressed on multiple cells in the striatum, however little is known about the contributions of specific MOR populations to alcohol drinking behaviors. The current study used mice with a genetic deletion of MOR in cholinergic cells (ChAT-Cre/Oprm1fl/fl) to examine the role of MORs expressed in cholinergic interneurons (CINs) in home cage self-administration paradigms. Male and female ChAT-Cre/Oprm1fl/fl mice were generated and heterozygous Cre+ (knockout) and Cre- (control) mice were tested for alcohol consumption in two drinking paradigms: limited access "Drinking in the Dark" and intermittent access. Quinine was added to the drinking bottles in the DID experiment to test aversion-resistant, "compulsive" drinking. Nicotine and sucrose drinking were also assessed so comparisons could be made with other rewarding substances. Cholinergic MOR deletion did not influence consumption or preference for ethanol (EtOH) in either drinking task. Differences were observed in aversion-resistance in males with Cre + mice tolerating lower concentrations of quinine than Cre-. In contrast to EtOH, preference for nicotine was reduced following cholinergic MOR deletion while sucrose consumption and preference was increased in Cre+ (vs. Cre-) females. Locomotor activity was also greater in females following the deletion. These results suggest that cholinergic MORs participate in preference for rewarding substances. Further, while they are not required for consumption of alcohol alone, cholinergic MORs may influence the tendency to drink despite negative consequences.


Assuntos
Consumo de Bebidas Alcoólicas , Camundongos Knockout , Quinina , Receptores Opioides mu , Recompensa , Animais , Receptores Opioides mu/genética , Receptores Opioides mu/metabolismo , Masculino , Feminino , Camundongos , Quinina/farmacologia , Quinina/administração & dosagem , Consumo de Bebidas Alcoólicas/genética , Consumo de Bebidas Alcoólicas/psicologia , Nicotina/farmacologia , Etanol/farmacologia , Etanol/administração & dosagem , Neurônios Colinérgicos/efeitos dos fármacos , Neurônios Colinérgicos/fisiologia , Neurônios Colinérgicos/metabolismo , Autoadministração , Sacarose/administração & dosagem , Aprendizagem da Esquiva/efeitos dos fármacos , Aprendizagem da Esquiva/fisiologia , Interneurônios/efeitos dos fármacos , Interneurônios/fisiologia , Interneurônios/metabolismo
11.
J Am Soc Mass Spectrom ; 35(5): 902-911, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38609335

RESUMO

Traditionally, mass spectrometry (MS) output is the ion abundance plotted versus the ionic mass-to-charge ratio m/z. While employing only commercially available equipment, Charge Determination Analysis (CHARDA) adds a third dimension to MS, estimating for individual peaks their charge states z starting from z = 1 and color coding z in m/z spectra. CHARDA combines the analysis of ion signal decay rates in the time-domain data (transients) in Fourier transform (FT) MS with the interrogation of mass defects (fractional mass) of biopolymers. Being applied to individual isotopic peaks in a complex protein tandem (MS/MS) data set, CHARDA aids peptide mass spectra interpretation by facilitating charge-state deconvolution of large ionic species in crowded regions, estimating z even in the absence of an isotopic distribution (e.g., for monoisotopic mass spectra). CHARDA is fast, robust, and consistent with conventional FTMS and FTMS/MS data acquisition procedures. An effective charge-state resolution Rz ≥ 6 is obtained with the potential for further improvements.


Assuntos
Análise de Fourier , Espectrometria de Massas em Tandem , Espectrometria de Massas em Tandem/métodos , Biopolímeros/química , Biopolímeros/análise , Íons/química , Cor
12.
Biochemistry (Mosc) ; 89(2): 212-222, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38622091

RESUMO

Quinone derivatives of triphenylphosphonium have proven themselves to be effective geroprotectors and antioxidants that prevent oxidation of cell components with participation of active free radicals - peroxide (RO2·), alkoxy (RO·), and alkyl (R·) radicals, as well as reactive oxygen species (superoxide anion, singlet oxygen). Their most studied representatives are derivatives of plastoquinone (SkQ1) and ubiquinone (MitoQ), which in addition to antioxidant properties also have a strong antibacterial effect. In this study, we investigated antibacterial properties of other quinone derivatives based on decyltriphenylphosphonium (SkQ3, SkQT, and SkQThy). We have shown that they, just like SkQ1, inhibit growth of various Gram-positive bacteria at micromolar concentrations, while being less effective against Gram-negative bacteria, which is associated with recognition of the triphenylphosphonium derivatives by the main multidrug resistance (MDR) pump of Gram-negative bacteria, AcrAB-TolC. Antibacterial action of SkQ1 itself was found to be dependent on the number of bacterial cells. It is important to note that the cytotoxic effect of SkQ1 on mammalian cells was observed at higher concentrations than the antibacterial action, which can be explained by (i) the presence of a large number of membrane organelles, (ii) lower membrane potential, (iii) spatial separation of the processes of energy generation and transport, and (iv) differences in the composition of MDR pumps. Differences in the cytotoxic effects on different types of eukaryotic cells may be associated with the degree of membrane organelle development, energy status of the cell, and level of the MDR pump expression.


Assuntos
Antineoplásicos , Benzoquinonas , Mitocôndrias , Animais , Mitocôndrias/metabolismo , Antioxidantes/farmacologia , Compostos Organofosforados/farmacologia , Plastoquinona/farmacologia , Antibacterianos/farmacologia , Antibacterianos/metabolismo , Antineoplásicos/farmacologia , Mamíferos/metabolismo
13.
Artigo em Inglês | MEDLINE | ID: mdl-38428676

RESUMO

The aim of this study is to describe the anaesthesia management of two patients undergoing carinal resection under veno-venous extracorporeal membrane oxygenation (VV ECMO). In both cases, anaesthesia was induced and then maintained with inhalational agents during pneumonectomy and mediastinoscopy (respectively). Then the jugular and femoral veins were cannulated and VV ECMO was started after heparinization. One of the patients presented bleeding during surgery, which was treated with low-dose vasopressors (norepinephrine) and transfusion of platelets, fresh frozen plasma, and concentrated red blood cells. During VV ECMO, anaesthesia was maintained with target-controlled infusion of propofol. VV ECMO can be expected to improve surgical conditions in tracheal surgery; however, it is still a novel technique in this context. In selected patients, it would guarantee ventilatory support during carinal resection, but it is essential to carefully plan anaesthesia maintenance and prepare for VV ECMO-related complications. This technique should only be used in tertiary centres with experience in VV ECMO management.


Assuntos
Oxigenação por Membrana Extracorpórea , Traqueia , Humanos , Oxigenação por Membrana Extracorpórea/métodos , Masculino , Traqueia/cirurgia , Pessoa de Meia-Idade , Feminino , Pneumonectomia/métodos , Neoplasias da Traqueia/cirurgia , Idoso , Adulto , Perda Sanguínea Cirúrgica/prevenção & controle
14.
Orthop Rev (Pavia) ; 16: 91505, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38469575

RESUMO

Case: A 62-year-old woman presenting with ankle pain was initially treated for a non-displaced fracture. Persistent pain despite months of conservative management for her presumed injury prompted repeat radiographs which demonstrated the progression of a lytic lesion and led to an orthopedic oncology referral. Following a complete work-up, including biopsy and staging, she was diagnosed with colorectal carcinoma metastatic to the distal fibula. Conclusion: Secondary tumors of the fibula are uncommon but an important diagnosis to consider for intractable lower extremity pain especially in patients with history of malignancy or lack of age-appropriate cancer screening.

15.
Nutrients ; 16(5)2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38474751

RESUMO

Only 20% of patients with muscle-invasive bladder carcinoma respond to cisplatin-based chemotherapy. Since the natural phytochemical sulforaphane (SFN) exhibits antitumor properties, its influence on the adhesive and migratory properties of cisplatin- and gemcitabine-sensitive and cisplatin- and gemcitabine-resistant RT4, RT112, T24, and TCCSUP bladder cancer cells was evaluated. Mechanisms behind the SFN influence were explored by assessing levels of the integrin adhesion receptors ß1 (total and activated) and ß4 and their functional relevance. To evaluate cell differentiation processes, E- and N-cadherin, vimentin and cytokeratin (CK) 8/18 expression were examined. SFN down-regulated bladder cancer cell adhesion with cell line and resistance-specific differences. Different responses to SFN were reflected in integrin expression that depended on the cell line and presence of resistance. Chemotactic movement of RT112, T24, and TCCSUP (RT4 did not migrate) was markedly blocked by SFN in both chemo-sensitive and chemo-resistant cells. Integrin-blocking studies indicated ß1 and ß4 as chemotaxis regulators. N-cadherin was diminished by SFN, particularly in sensitive and resistant T24 and RT112 cells, whereas E-cadherin was increased in RT112 cells (not detectable in RT4 and TCCSup cells). Alterations in vimentin and CK8/18 were also apparent, though not the same in all cell lines. SFN exposure resulted in translocation of E-cadherin (RT112), N-cadherin (RT112, T24), and vimentin (T24). SFN down-regulated adhesion and migration in chemo-sensitive and chemo-resistant bladder cancer cells by acting on integrin ß1 and ß4 expression and inducing the mesenchymal-epithelial translocation of cadherins and vimentin. SFN does, therefore, possess potential to improve bladder cancer therapy.


Assuntos
Isotiocianatos , Sulfóxidos , Neoplasias da Bexiga Urinária , Bexiga Urinária , Humanos , Bexiga Urinária/metabolismo , Cisplatino , Gencitabina , Vimentina , Linhagem Celular Tumoral , Neoplasias da Bexiga Urinária/tratamento farmacológico , Caderinas/metabolismo , Integrinas/metabolismo , Integrinas/uso terapêutico
16.
ACS Pharmacol Transl Sci ; 7(3): 787-796, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38481686

RESUMO

Rapamycin is a natural antifungal, immunosuppressive, and antiproliferative compound that allosterically inhibits mTOR complex 1. The ubiquitin-proteasome system (UPS) responsible for protein turnover is usually not listed among the pathways affected by mTOR signaling. However, some previous studies have indicated the interplay between the UPS and mTOR. It has also been reported that rapamycin and its analogs can allosterically inhibit the proteasome itself. In this work, we studied the molecular effect of rapamycin and its analogs (rapalogs), everolimus and temsirolimus, on the A549 cell line by expression proteomics. The analysis of differentially expressed proteins showed that the cellular response to everolimus treatment is strikingly different from that to rapamycin and temsirolimus. In the cluster analysis, the effect of everolimus was similar to that of bortezomib, a well-established proteasome inhibitor. UPS-related pathways were enriched in the cluster of proteins specifically upregulated upon everolimus and bortezomib treatments, suggesting that both compounds have similar proteasome inhibition effects. In particular, the total amount of ubiquitin was significantly elevated in the samples treated with everolimus and bortezomib, and analysis of the polyubiquitination patterns revealed elevated intensities of the ubiquitin peptide with a GG modification at the K48 residue, consistent with a bottleneck in proteasomal protein degradation. Moreover, the everolimus treatment resulted in both ubiquitin phosphorylation and generation of a significant amount of semitryptic peptides, illustrating the increase in the protease activity. These observations suggest that everolimus affects the UPS in a unique way, and its mechanism of action is different from that of its close chemical analogs, rapamycin and temsirolimus.

17.
Polymers (Basel) ; 16(6)2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38543362

RESUMO

In this study, Rhodamine B-containing chitosan-based films were prepared and characterized using their mechanical, photophysical, and antibacterial properties. The films were synthesized using the casting method and their mechanical properties, such as tensile strength and elongation at break, were found to be dependent on the chemical composition and drying process. Infrared spectroscopy and X-ray diffraction analysis were used to examine the chemical structure and degree of structural perfection of the films. The photophysical properties of the films, including absorption spectra, fluorescence detection, emission quantum yields, and lifetimes of excited states, were studied in detail. Rhodamine B-containing films exhibited higher temperature sensitivity and showed potential as fluorescent temperature sensors in the physiological range. The antibacterial activity of the films was tested against Gram-positive bacteria S. aureus and Gram-negative bacteria E. coli, with Rhodamine B-containing films demonstrating more pronounced antibacterial activity compared to blank films. The findings suggest that the elaborated chitosan-based films, particularly those containing Rhodamine B can be of interest for further research regarding their application in various fields such as clinical practice, the food industry, and agriculture due to their mechanical, photophysical, and antibacterial properties.

18.
Artigo em Inglês | MEDLINE | ID: mdl-38305349

RESUMO

STUDY DESIGN: Retrospective single-center study. OBJECTIVES: to evaluate the results of surgical treatment in patients with double crush syndrome associated with cervical radiculopathy and upper limb peripheral nerve compression after staged and simultaneous operations. SUMMARY OF BACKGROUND DATA: Currently, choosing the optimal diagnostic and therapeutic modalities in treating patients with double crush syndrome remains unresolved. METHODS: The study included 79 patients with double crush syndrome (cervical radiculopathy and syndrome of Guyon's canal or Carpal tunnel syndrome). Two independent groups were studied: In the Staged Group (n=35), we performed a cervical decompression with stabilization and peripheral nerve decompression at separate days due to ongoing clinical symptoms (average interval between interventions being 22 (18;26) days). In the Simultaneous Group (n=33), we performed both the cervical spine surgery, as well as the peripheral nerve procedures in one surgical session. Total operative time, estimate blood loss, length of hospitalization, complications and clinical data (NDI score, SF-36, VAS neck pain score, VAS arm pain score, Disabilities of Arm, Shoulder and Hand (DASH) score, Macnab scale) were compared. We used the Mann-Whitney (MW) test for intergroup comparisons, Wilcoxon criterion for dependent samples, and Fisher's exact test for binomial parameters. RESULTS: There was a significantly lower operative time, duration of inpatient treatment and temporary disability in the Simultaneous Group (P=0.01, P=0.04 and P=0.006 respectively). Comparative analysis did not reveal significant intergroup differences using NDI, VAS and DASH (P>0.05), whereas, at discharge, significantly better clinical parameters were appreciated for the Simultaneous Group using SF-36 and Macnab scores (P=0.04 and P=0.03, respectively). At Last Follow-up, an intra-group analysis revealed comparable clinical effectiveness between the two approaches (P>0.05). CONCLUSION: Comparison of the effectiveness of simultaneous and staged surgery revealed comparable long-term clinical outcomes. However, simultaneous surgery conveys clinically important advantages in terms of surgical time, anesthesia duration, length of hospitalization and patient disability. LEVEL OF EVIDENCE: 3.

19.
Biomedicines ; 12(2)2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38398045

RESUMO

The effect of an extremely low frequency alternating magnetic field (ELF AMF) at frequencies of 17, 48, and 95 Hz at 100 mT on free and internalized 4T1 breast cancer cell submicron magnetic mineral carriers with an anticancer drug, mitoxantrone, was shown. The alternating magnetic field (100 mT; 17, 48, 95 Hz; time of treatment-10.5 min with a 30 s delay) does not lead to the significant destruction of carrier shells and release of mitoxantrone or bovine serum albumin from them according to the data of spectrophotometry, or the heating of carriers in the process of exposure to magnetic fields. The most optimal set of factors that would lead to the suppression of proliferation and survival of cells with anticancer drug carriers on the third day (in comparison with the control and first day) is exposure to an alternating magnetic field of 100 mT in a pulsed mode with a frequency of 95 Hz. The presence of magnetic nanocarriers in cell lines was carried out by a direct label-free method, space-resolved Brillouin light scattering (BLS) spectrometry, which was realized for the first time. The analysis of the series of integrated BLS spectra showed an increase in the magnetic phase in cells with a growth in the number of particles per cell (from 10 to 100) after their internalization. The safety of magnetic carriers in the release of their constituent ions has been evaluated using atomic absorption spectrometry.

20.
ACS Appl Bio Mater ; 7(2): 1095-1114, 2024 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-38270084

RESUMO

Peripheral nerve injury poses a threat to the mobility and sensitivity of a nerve, thereby leading to permanent function loss due to the low regenerative capacity of mature neurons. To date, the most widely clinically applied approach to bridging nerve injuries is autologous nerve grafting, which faces challenges such as donor site morbidity, donor shortages, and the necessity of a second surgery. An effective therapeutic strategy is urgently needed worldwide to overcome the current limitations. Herein, a magnetic nerve guidance conduit (NGC) based on biocompatible biodegradable poly(3-hydroxybutyrate) (PHB) and 8 wt % of magnetite nanoparticles modified by citric acid (Fe3O4-CA) was fabricated by electrospinning. The crystalline structure of NGCs was studied by X-ray diffraction, which indicated an enlarged ß-phase of PHB in the composite conduit compared to a pure PHB conduit. Tensile tests revealed greater ductility of PHB/Fe3O4-CA: the composite conduit has Young's modulus of 221 ± 52 MPa and an elongation at break of 28.6 ± 2.9%, comparable to clinical materials. Saturation magnetization (σs) of Fe3O4-CA and PHB/Fe3O4-CA is 61.88 ± 0.29 and 7.44 ± 0.07 emu/g, respectively. The water contact angle of the PHB/Fe3O4-CA conduit is lower as compared to pure PHB, while surface free energy (σ) is significantly higher, which was attributed to higher surface roughness and an amorphous phase as well as possible PHB/Fe3O4-CA interface interactions. In vitro, the conduits supported the proliferation of rat mesenchymal stem cells (rMSCs) and SH-SY5Y cells in a low-frequency magnetic field (0.67 Hz, 68 mT). In vivo, the conduits were used to bridge damaged sciatic nerves in rats; pure PHB and composite PHB/Fe3O4-CA conduits did not cause acute inflammation and performed a barrier function, which promotes nerve regeneration. Thus, these conduits are promising as implants for the regeneration of peripheral nerves.


Assuntos
Nanopartículas de Magnetita , Neuroblastoma , Traumatismos dos Nervos Periféricos , Poli-Hidroxibutiratos , Ratos , Humanos , Animais , Traumatismos dos Nervos Periféricos/terapia , Ácido 3-Hidroxibutírico/farmacologia , Materiais Biocompatíveis/farmacologia , Nanopartículas de Magnetita/uso terapêutico , Hidroxibutiratos/farmacologia , Regeneração Nervosa/fisiologia
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