Search Results (1,326)

Accurate and detailed tissue characterization is a central goal in medical diagnostics, often requiring the combination of multiple imaging modalities. This study presents a multimodal imaging system that integrates mid-infrared (MIR) scanning with fluorescence imaging to enhance the chemical specificity and spatial resolution in biological samples. A motorized mirror allows rapid switching between MIR and fluorescence modes, enabling efficient, co-registered data acquisition. The MIR modality captures label-free chemical maps based on molecular vibrations, while the fluorescence channel records endogenous autofluorescence for additional biochemical contrast. Applied to mouse brain tissue, the system enabled the clear differentiation of gray matter and white matter, supported by the clustering analysis of spectral features. The addition of autofluorescence imaging further improved anatomical segmentation and revealed fine structural details. In mouse skin, the approach allowed the precise mapping of the layered tissue architecture. These results demonstrate that combining MIR scanning and fluorescence imaging provides complementary, label-free insights into tissue morphology and chemistry. The findings support the utility of this approach as a powerful tool for biomedical research and diagnostic applications, offering a more comprehensive understanding of tissue composition without relying on staining or external markers. Full article

Background: The detection of circulating tumor cells (CTCs) holds significant promise for the diagnosis and monitoring of lung cancer (LC). However, the clinical utility of CTCs is limited by the heterogeneity of their phenotypes and the shortcomings of existing detection methods, which often rely on epithelial markers like EpCAM. DNA aptamers offer a promising alternative due to their high affinity, stability, and ability to recognize diverse cancer-specific biomarkers. Methods: This study utilized DNA aptamers LC-17 and LC-18, previously selected against primary lung tumor tissue, to isolate and detect CTCs in the peripheral blood of 43 non-small cell lung cancer (NSCLC) patients. Mass spectrometry (LC-MS/MS) was employed to identify the target proteins of aptamer LC-17. CTCs from patients’ blood and healthy donors were isolated via filtration after erythrocyte and lymphocyte lysis and stained with FAM-labeled LC-17 and LC-18 aptamers for detection using fluorescence and light microscopy. Results: Mass spectrometry identified neutrophil defensin 1 (DEFA1) and peroxiredoxin-2 (PRDX2) as the primary protein targets of aptamer LC-17 in CTCs, both of which were absent in healthy donor samples. CTC enumeration revealed statistically significant correlations between elevated CTC counts (>3 cells/4 mL blood) and advanced primary tumor size (T4 vs. T1–T3, p = 0.012), extensive regional lymph node metastasis (N3 vs. N1–N2, p = 0.014), and shorter overall survival (median 24 vs. 32 months, p < 0.05). Conclusions: The developed aptamer-based liquid biopsy method effectively captures heterogeneous CTC populations independent of EpCAM expression. The strong correlation of CTC counts with disease progression and survival underscores their clinical relevance as a prognostic biomarker in NSCLC. This approach presents a viable, non-invasive tool for disease monitoring and stratification of NSCLC patients, with potential for integration into clinical practice. Full article

Diabetic peripheral neuropathy (DPN) is a common complication of diabetes, marked by Schwann cell dysfunction, demyelination, and impaired nerve regeneration. Although Schwann cells undergo phenotypic changes under hyperglycemic conditions, the underlying molecular mechanisms remain unclear. This study aimed to examine the effects of high glucose on Schwann cell phenotype and assess the involvement of the mTOR signaling pathway. Primary Schwann cells were isolated from rat sciatic nerves and cultured in media containing 5 mM (control), 25 mM, or 50 mM glucose for five days. Immunofluorescence staining and corrected total cell fluorescence (CTCF) analysis were used to evaluate expression of key markers: c-Jun, Krox-20, p75^NTR, MBP, mTOR, phosphorylated mTOR (Ser2448), and AKR1B1. Among these, significant changes were observed in MBP (p = 0.002), total mTOR (p = 0.001), and phosphorylated mTOR (Ser2448) (p = 0.0179), indicating impaired mTOR activation and loss of myelin protein expression. Non-significant changes in the other markers are discussed as preliminary observations. These findings highlight mTOR dysregulation and impaired myelin protein expression as central features of Schwann cell responses to hyperglycemia, which may contribute to the development of DPN. Full article

The biocompatibility of materials used in biomedical applications, especially those in direct contact with human tissue, is crucial to ensuring their safety. Ensuring material biocompatibility requires a wide range of in vitro and in vivo tests, with in vitro tests using cell culture systems being the first step in biomaterial characterization. Among the commonly used methods for assessing cell viability are colorimetric tests, such as MTT and LDH assays. While these assays provide valuable information about cell viability, their results can be affected by biochemical substances. This study focused on evaluating the reliability of MTT and LDH assays in nicotinamide-supplemented medium, which optimized culture conditions for the differentiation of ARPE-19 cells. The results were compared with a live/dead viability test based on fluorescence staining, providing insight into the effectiveness of different cell viability assessment methods in this specific context. This research is important in developing biomaterials for retinal prostheses, where maintaining high biocompatibility is essential for successful implantation. Full article

Alpha-synuclein (αsyn) misfolding and aggregation underlie several neurodegenerative disorders, including Parkinson’s disease. Early oligomeric intermediates are particularly toxic yet remain challenging to detect and characterize within cellular systems. Here, we employed the luminescent conjugated oligothiophene h-FTAA to investigate early aggregation events of human wildtype (huWT) and A53T-mutated αsyn (huA53T) both in vitro and in HEK293 cells stably expressing native human-αsyn. Comparative fibrillation assays revealed that h-FTAA detected αsyn aggregation with higher sensitivity and earlier onset than Thioflavin T, with the A53T variant displaying accelerated fibrillation. HEK293 cells stably expressing huWT- or huA53T-αsyn were exposed to respective pre-formed fibrils (PFFs), assessed via immunocytochemistry, h-FTAA staining, spectral emission profiling, and fluorescence lifetime imaging microscopy (FLIM). Notably, huA53T PFFs promoted earlier aggregation patterns and yielded narrower fluorescence lifetime distributions compared with huWT PFFs. Spectral imaging showed h-FTAA emission maxima (~550–580 nm) red-shifted and broadened in cells along with variable lifetimes (0.68–0.87 ns), indicating heterogeneous aggregate conformations influenced by cellular milieu. These findings demonstrate that h-FTAA is useful for distinguishing early αsyn conformers in living systems and, together with stable αsyn-expressing HEK293 cells, offers a platform for probing early αsyn morphotypes. Taken together, this opens for further discovery of biomarkers and drugs that can interfere with αsyn aggregation. Full article

Background: Over the last years, the phenomenon of entosis, a form of cell-in-cell structure, has been highlighted in various tumors, including poorly treatable breast or pancreatic cancers. Nevertheless, not only the biological properties, but also the molecular drivers of entosis remain unclear. Here, we evaluated SRC tyrosine kinase, a key proto-oncogene, and podoplanin (PDPN), a membrane glycoprotein, as potential regulators of entotic cell formation. Methods: In the study, two entosis-competent cell lines, BxPC-3 and MFC-7, originating from pancreatic and breast cancers, respectively, were used. SRC or PDPN genes were silenced using dedicated siRNA and the frequency of entotic structure formation was assessed using fluorescent staining and confocal imaging. Results: It was found that BxPC-3 cells deficient in PDPN are more prone to form entotic structures and that over 90% of all entotic figures formed by mixed PDPN⁺ and PDPN^- BxPC-3 cells involved PDPN-silenced cells. The SRC data supports this observation, as the suppressed entotic formation ability presented by SRC-deficient cells was linked with increased expression of PDPN. Even though the observed effects were mainly limited to BxPC-3 cells, as PDPN expression in MCF-7 cells is restricted, overall, the obtained data suggest a strong anti-entotic function of PDPN. Additionally, the performed Western blotting indicated the activation of ezrin-radixin-moesin (ERM) proteins in PDPN-deficient cells. Conclusions: Taken together, these data suggest that the negatively controlled PDPN-ERM axis may act as a molecular factor controlling the development of entotic structures and cells with naturally low PDPN expression may be more liable to form entoses. Full article

Background/Objectives: Synovial sarcoma (SS) is an aggressive soft-tissue tumor characterized by the chromosomal translocation t(X;18) (p11.2;q11.2), most commonly involving the fusion of the SYT gene on chromosome 18 with the SSX1 or SSX2 genes on chromosome X. This study aims to explore the clinicopathological and molecular characteristics of synovial sarcoma in a cohort of Moroccan patients. Methods: We analyzed 48 cases of synovial sarcoma using formalin-fixed, paraffin-embedded (FFPE) tissue samples. Histological grading was performed according to the FNCLCC system. Immunohistochemical staining was employed to detect cytokeratin (CK) and epithelial membrane antigen (EMA). Molecular analysis included fluorescence in situ hybridization (FISH) to identify SS18 gene rearrangements and reverse transcription–polymerase chain reaction (RT-PCR) to detect SYT-SSX fusion transcripts. Results: Among the cohort, 56% of cases showed SS18 gene rearrangements via FISH, while RT-PCR confirmed the presence of SS18-SSX1 and SS18-SSX2 transcripts in 60% and 32% of cases, respectively. The remainder was classified as undifferentiated sarcoma. Notably, no significant associations were observed between SYT-SSX fusion type and clinicopathological features. Conclusions: These findings underscore the importance of integrating molecular techniques for precise diagnosis in synovial sarcoma. The results align with global patterns, emphasizing the necessity for molecular testing to enhance diagnostic accuracy and informing potential therapeutic advancements. Full article

Podocytopathy, characterized by proteinuria, contributes significantly to kidney diseases, with hypertension playing a key role in damaging podocytes and the glomerular filtration barrier (GFB). The lack of functional in vitro models, however, impedes research and treatment development for hypertensive podocytopathy. We established a novel constant pressure-driven podocyte-on-chip model, utilizing our previously developed dynamic staining self-assembly cell array chip (SACA chip) and 3D printing. This platform features a differentiated podocyte monolayer under controlled hydrostatic pressures, mimicking the epithelial side of the GFB. Using this platform, we investigated mechanical force-dependent permeability to three sizes of fluorescent dextran under varying hydrostatic pressures, comparing the results with a puromycin aminonucleoside (PAN)-induced injury model. We observed that external pressures induced size-dependent permeability changes and altered cell morphology. Higher pressures led to greater macromolecule infiltration, especially for larger dextran (70 kDa, 500 kDa). Mature podocytes exhibited immediate, pressure-dependent cytoskeleton rearrangements, with better recovery at lower pressures (20 mmHg) but irreversible injury at higher pressures (40, 60 mmHg). These morphological changes were also corroborated by dynamic mRNA expression of cytoskeleton-associated proteins, Synaptopodin and ACTN4. This platform offers a promising in vitro tool for investigating the pathomechanisms of hypertension-induced podocytopathy, performing on-chip studies of the GFB, and conducting potential drug screening. Full article

Hops essential oil (HEO), a by-product of the brewing industry, has known antibacterial and antifungal properties, but its antiparasitic effects remain underexplored. This study evaluated the cytotoxicity of HEO and its predominant monoterpene, myrcene, in intestinal cells and assessed their ability to reduce Cryptosporidium parvum infection in vitro. The cytotoxicity (IC₅₀) of HEO and myrcene was determined in HCT-8 intestinal cells using flow cytometry and propidium iodide staining after 24 and 48 h of exposure. The anti-Cryptosporidium activity of HEO and myrcene was assessed by infecting confluent HCT-8 cells with C. parvum sporozoites (1 × 10⁴ sporozoites/mL) and treating them with bioactives below their IC₅₀ values. Two treatment modalities were tested: (1) immediate treatment during infection (invasion) and (2) treatment initiated 2 h after infection (growth). Parasite growth was quantified using an immunofluorescence assay with a fluorescence-conjugated anti-Cryptosporidium antibody. HEO exhibited low cytotoxicity (IC₅₀ = 382.7 µg/mL), while myrcene showed higher cytotoxicity (IC₅₀ = 240.6 µg/mL). HEO reduced C. parvum growth in a dose-dependent manner, with IC₅₀ values of 45.8 and 58.7 µg/mL under either modality, respectively. Myrcene alone demonstrated greater anti-Cryptosporidium activity, with IC₅₀ values lower under the invasion modality (17.7 µg/mL) than the growth modality (28.1 µg/mL) on average for both food-grade and analytical standards. HEO and myrcene exhibited significant in vitro anti-Cryptosporidium activity, highlighting their potential as novel therapeutic agents against cryptosporidiosis. Full article

Photodynamic inactivation and antimicrobial photodynamic therapy (PDI/APDT) based on the toxic properties of reactive oxygen species (ROS), which are generated by a number of photoexcited dyes, are promising for preventing and treating infections, especially those associated with drug-resistant pathogens. The negatively charged bacterial cell surface attracts polycationic photosensitizers, which contribute to the vulnerability of the bacterial plasma membrane to ROS. The integrity of the plasma membrane is critical for the viability of the bacterial cell. Polycationic phthalocyanines are regarded as promising photosensitizers due to their high quantum yields of ROS generation (mainly singlet oxygen), high extinction coefficients in the far-red spectral range, and low dark toxicity. For application in PDI/APDT, the wide range of possibilities of modifying the chemical structure of phthalocyanines is particularly valuable, especially by introducing various peripheral and non-peripheral substituents into the benzene rings. Depending on the type and location of such substituents, it is possible to obtain photosensitizers with different photophysical properties, photochemical activity, solubility in an aqueous medium, biocompatibility, and tropism for certain structures of photoinactivation targets. In this study, we tested novel water-soluble Zn (II) phthalocyanines bearing four 4-((diethylmethylammonium)methyl)phenoxy substituents with symmetric and asymmetric charge distributions for photodynamic antibacterial activity and compared them with those of water-soluble octacationic zinc octakis(cholinyl)phthalocyanine. The obtained results allow us to conclude that the studied tetracationic aryloxy-substituted Zn(II) phthalocyanines effectively bind to the oppositely charged cell wall of the Gram-negative bacteria E. coli. This finding is supported by data on bacteria’s zeta potential neutralization in the presence of phthalocyanine derivatives and fluorescence microscopy images of stained bacterial cells. Asymmetric substitution influences the aggregation and fluorescent characteristics but has little effect on the ability of the studied tetracationic phthalocyanines to sensitize the bioluminescent E. coli K12 TG1 strain. Both symmetric and asymmetric aryloxy-substituted phthalocyanines are no less effective in PDI than the water-soluble zinc octakis(cholinyl)phthalocyanine, a photosensitizer with proven antibacterial activity, and have significant potential for further studies as antibacterial photosensitizers. Full article

Background/Objectives: In spite of substantial treatment progress, cancer persists as a leading health challenge. With the slow advancement in developing new anticancer agents, drug repurposing provides a promising strategy to enhance cancer therapy. This study investigates the antiproliferative and antimetastatic properties of two 3-Hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors, atorvastatin and rosuvastatin, which represent lipophilic and hydrophilic statins, respectively. Methods: Growth inhibition was evaluated in a panel of human cancer cells using the standard MTT assay. Apoptotic effects were determined through flow cytometry, caspase-3 activity assay, mitochondrial membrane potential assessment, and Hoechst/Propidium iodide fluorescent double staining. Migration and invasion assays were conducted using wound-healing and Boyden chamber assays, respectively. Results: Atorvastatin demonstrated more pronounced growth-inhibitory effects than rosuvastatin, with the IC₅₀ values in the range of 2.57–61.01 µM. Atorvastatin exhibited both biochemical and morphological indicators of apoptosis. Flow cytometry revealed cell cycle disruptions and increased sub-G1 apoptotic populations in HPV-positive oral squamous carcinoma cells (UPCI-SCC-154) and HPV-negative cervical cancer cells (C33A). Atorvastatin also significantly inhibited cell migration and invasion in the tested cell lines. Conclusions: Our results highlight the promising anticancer potential of atorvastatin in cervical cancer and oral squamous carcinoma cells. However, these findings are limited to in vitro models and warrant further in vivo validation. Full article

Upon activation, neutrophils perform three distinct functions: phagocytosis, degranulation of antimicrobial substances into the extracellular medium, and release of neutrophil extracellular traps. Determination of the nuclear area expansion of neutrophils activated to release neutrophil extracellular traps has become critical in demonstrating early neutrophil activation and has become standard. Here, we demonstrate an automated method for measuring nuclear area expansion in two different mammalian species: canine and bovine. For both species, neutrophils were isolated from peripheral blood and co-incubated with fresh spermatozoa for up to 120 min for canine neutrophil–spermatozoa and recently thawed cryopreserved spermatozoa up to 240 min for bovine neutrophil–spermatozoa. Fluorescence images were acquired using a TissueFAXS microscope and then analyzed using StrataQuest v.7.0 software. The images show the release of neutrophil extracellular traps upon activation with spermatozoa for both species, as evidenced by the co-localization of neutrophil elastase and DNA staining. Neutrophil nuclei were expanded as early as 15 min and were detected at up to 120 min in both species. Analysis by nuclei segmentation showed that the data sets generated for both species were reliable and consistent with previously published methods. The method was developed as an automated alternative for measuring the area expansion of neutrophil nuclei in different species. Full article

Expansion microscopy (ExM) enables conventional light microscopes to achieve nanoscale resolution by physically enlarging biological specimens. While ExM has been widely applied in neurobiology, it has not been adapted for the enteric nervous system (ENS). Here, we provide a detailed and reproducible protocol for applying ExM to mouse colonic ENS tissue. The procedure includes preparation of the external muscle layers with the myenteric plexus, histochemical staining for NADPH-diaphorase, immunostaining for glial fibrillary acidic protein (GFAP), anchoring of biomolecules, gelation, proteinase K digestion, and isotropic expansion in a swellable polymer matrix. Step-by-step instructions, required reagents, and critical parameters are described to ensure robustness and reproducibility. Using this protocol, tissues expand 3–5-fold, allowing neuronal somata, fibers, and glial cell processes to be clearly visualized by standard brightfield or fluorescence microscopy. The tissue architecture is preserved, with distortion in the X–Y plane of about 7%. This protocol provides a reliable framework for high-resolution structural analysis of the ENS and can be readily adapted to other peripheral tissues. Full article

Background: The disialoganglioside GD2, located at the plasma membrane, is selectively overexpressed in various solid tumors, where it contributes to tumor growth and the development of an aggressive tumor phenotype. Thus, over the last two decades GD2 has been gaining importance both as a tumor marker and a therapy target. In neuroblastoma, anti-GD2 monoclonal antibodies and CAR T-cells have become an integral part of the multimodal treatment for relapsed or refractory high-risk cases, which continue to associate with poor prognosis. GD2 characterization in neuroblastoma is well established for bone marrow aspirates and biopsies, but remains challenging in tumoral tissue samples, mostly due to epitope loss upon fixation. Aims: The aim of our work was to assess a new protocol by staining GD2 in tissue specimens prior to fixation. Methods: Positive controls were tissue specimens from patients with histologically confirmed neuroblastoma and GD2 expression in bone marrow aspirate (n = 5). Nephroblastoma or Hodgkin lymphoma samples were considered as negative controls (n = 5). Tissue staining was performed prior to fixation with either anti-GD2 antibody or isotype control, followed by secondary antibody staining and subsequent paraffinization. To examine GD2 staining before and after paraffinization, fluorescence images were acquired using 3D and 2D immunofluorescence microscopy techniques respectively. Results: GD2 signal was detected in all positive controls, while absent in all negative controls. After fixation, paraffinization and slicing no relevant signal loss was observed. Nevertheless, sufficient staining of 3D specimens required long incubation times, which led to increased cytolysis of the unfixed tissue. Conclusions: We were able to establish and validate a novel protocol to reliably perform immunostaining of the membrane antigen GD2 in unfixed, primary neuroblastoma tissue. Although including few limitations, this staining workflow enables relatively quick assessment of GD2 status and thus, might represent a relevant diagnostic tool within the framework of tumor staging and precision medicine. Full article

Background: Chronic inflammation drives colorectal cancer (CRC) progression, with PAR-2, a G-protein coupled receptor, linking extracellular inflammatory signals to tumor-promoting pathways via ERK1/2 phosphorylation, calcium mobilization, TNF-α upregulation, and apoptosis suppression. While curcumin has notable anti-inflammatory and anti-cancer properties, its effects on PAR-2 signaling in inflammation-driven CRC remain underexplored. Objective: This study investigates how curcumin modulates PAR-2 expression and downstream oncogenic signaling in inflammation-driven CRC cells and explores its potential direct interaction with PAR-2 at the structural level. Methods: HT 29 and Caco-2 CRC cell lines were exposed to lipopolysaccharide (LPS) to induce an inflammatory phenotype, followed by treatment with curcumin at 50 µM and 100 µM. PAR-2 and PAR-1 expression, along with downstream markers including ERK1/2, p-ERK, TNF-α, caspase-8, cleaved caspase-8, caspase-3, Bcl 2, and Bax, were analyzed by Western blot and quantitative PCR. Calcium mobilization was assessed using Fluo-4 dye-based fluorescence imaging. Apoptosis was quantified using MTT viability assays, AO/EtBr dual staining, and Annexin V/PI flow cytometry. In parallel, AlphaFold-predicted structural models of PAR-2 were used to perform molecular docking with curcumin using CB-Dock2, to identify potential binding pockets and assess binding energetics. Results: Curcumin selectively downregulated PAR-2—but not PAR-1—at both transcript and protein levels in a dose-dependent manner. This downregulation was accompanied by suppression of ERK phosphorylation and calcium signaling, inhibition of TNF-α secretion, and reversal of the anti-apoptotic signaling axis (Bcl 2 downregulation and Bax and caspase-3/-8 upregulation). Functional assays confirmed enhanced apoptosis in curcumin-treated cells. Computational docking revealed a high-affinity binding interaction between curcumin and the transmembrane domain of PAR-2, supporting the hypothesis of direct G-Protein-Coupled Receptor (GPCR) modulation. Conclusions: Our findings reveal that curcumin targets the PAR-2/ERK/TNF-α axis and reactivates apoptotic pathways in inflammation-driven CRC, establishing it as a potent, mechanistically validated candidate for therapeutic repurposing in CRC. Full article