Number Of Cells Research Articles

TUDY OF CHRONIC TOXICITY OF AN IMPROVED A-SILICONE IMPRESSION MATERIAL PRODUCED IN UKRAINE

The objective of this study is to evaluate the potential toxic effects of an improved A-silicone impression material with decorative properties on the organs and mucous membranes of laboratory animals. Materials and Methods The experiment was conducted on white laboratory rats aged 9 months and weighing 230–285 g. Findings indicate that prolonged contact (30 days) with the material does not result in significant changes in the function of major organ systems in these laboratory rats. Results. A single exposure of laboratory rats to A-silicone impression material with disinfectant properties did not cause significant changes in the physiological state of the animals. Weights of internal organs, including the liver, spleen, heart, and adrenal glands, remained within normal limits, indicating that the material had no toxic effects. The analysis of the peripheral blood composition did not reveal any abnormalities in the number of red blood cells, leukocytes, hemoglobin and other cellular components. The functional state of the liver and kidneys, including the activity of the enzymes AlаT and AсаT, levels of total protein, albumin, creatinine and urea, remained stable and did not change under the influence of the material. There was also no effect on carbohydrate metabolism. No abnormalities in protein synthesis and nitrogen excretion functions were detected, which confirms the safety of the material during the 30-day observation. Conclusion. It was established that this material in the tested dose does not affect the enzyme-synthetic function of the liver and does not exhibit cytolytic effects. The material was found to have no toxic impact on liver function with prolonged use, nor does it cause statistically significant deviations in the measured indicators between the control and experimental groups. The absence of sugar, ketones, and protein in the urine indicates no adverse effect on the renal nitrogen-excreting and saluretic functions, as well as on the vital organs of the rats.

Carnosol alleviates cisplatin–induced acute kidney injury by regulating apoptosis and pyroptosis

AbstractThe use of the common anticancer drug cisplatin (CP) in clinical practice often leads to acute kidney injury (AKI); however, no protective therapy is available. Therefore, new drugs that reduce the nephrotoxicity induced by CP are urgently needed. Carnosol (CA) is an antioxidant found. We investigated the renoprotective effects of CA on CP‐induced AKI in male C57BL/6 mice and HK2 cells. CA mitigated renal dysfunction, histopathological changes and tubular injury in vivo, as indicated by the expression of NGAL, KIM1 and HMGB1. Moreover, the numbers of apoptotic cells and the expression of apoptotic proteins were dramatically reduced after CA treatment in mouse kidneys and HK2 cells. CA significantly ameliorated CP‐induced inflammation and decreased TNF‐α and IL‐1β levels in vivo and in vitro and macrophage infiltration in the mouse kidney. CA decreased the expression levels of p‐p65/p65, NLRP3 and ASC, which indicates that CA suppressed the activation of the NF‐κB/NLRP3 signaling axis induced by CP in vivo and in vitro. In addition, CA decreased the levels of certain protein in pyroptotic cells, as indicated by the expression of cleaved caspase‐1, GSDMD, and mature IL‐1β and IL‐18 in vivo and in vitro. Finally, CA reduced the level of cleaved caspase‐1, but those of GSDMD and NLRP3 protein were not significantly different after treatment with the NLRP3 inhibitor MCC950 and were elevated by the NLRP3 activator nigericin. In conclusion, this study revealed that CA protects against CP‐induced AKI by decreasing apoptosis and NF‐κB/NLRP3/GSDMD‐mediated pyroptosis, which provides new insight into the prevention of AKI.

Mathematical model of liver cirrhosis formation during morphological and molecular-genetic preclinical studies

BACKGROUND: Currently, researchers describe challenges in developing new treatments for fibrosis and cirrhosis: poor quality of preclinical models, insufficient trial duration, and lack of markers of therapeutic response. A separate task is to standardize the process of liver cirrhosis formation in preclinical trials, which is necessary to obtain accurate quantitative estimates in a short timeframe. AIM: This study aimed to develop a mathematical model for the formation of liver cirrhosis during preclinical trials. MATERIALS AND METHODS: Liver fibrosis and cirrhosis were induced in male Wistar rats using freshly prepared thioacetamide solution for 17 weeks. The area of connective tissue was determined as a percentage of the image area. The area of interlobular veins was measured in µm2. The numbers of cells expressing the FAP marker and the α-SMA marker were counted. The level of mRNA expression of the Vegfa and Yap1 genes was assessed by real-time polymerase chain reaction. A mathematical model for classifying observations into stages was constructed using multiple logistic regression with stepwise selection of predictors, followed by calculation of sensitivity, specificity, and area under the curve with a 95% confidence interval based on ROC analysis. RESULTS: As a result of the analysis, a mathematical model of liver cirrhosis formation was developed. The model is based on the values of two indicators: FAP+ cells and Yap1 mRNA and demonstrated good quality. The resulting value of the area under the ROC curve of 0.883 suggests good results for classifying cases. CONCLUSIONS: The mathematical model makes it possible to differentiate the stage of liver cirrhosis from the stage of fibrosis during preclinical studies. It provides a foundation for studying the pathogenesis of liver fibrosis and cirrhosis, identifying new potential molecular targets for antifibrotic therapy, and reducing the number of expensive, labor-intensive laboratory tests.

Tanshinone IIA Alleviates Pulmonary Fibrosis by Inhibiting Pyroptosis of Alveolar Epithelial Cells Through the MAPK Signaling Pathway

ABSTRACTThe current dearth of safe and efficacious pharmaceutical interventions for pulmonary fibrosis (PF) has prompted investigations into alternative treatments. This study aim to investigate the underlying mechanisms of Tanshinone IIA in the treatment of PF. PF was induced in a mouse model by intratracheal infusion of bleomycin (BLM), followed by gavage administration of varying concentrations of Tanshinone IIA. Lung tissue was obtained for pathological slides, proteomic and transcriptomic analyses. The target was predicted and analyzed using network pharmacology. Initially, an in vitro model in A549 cells was established by adding BLM, followed by treatment with varying concentrations of Tanshinone IIA. Subsequently, NAC and the ERK inhibitor, U0126, were individually introduced. Treatment with Tanshinone IIA in vivo decreased lung tissue lesions. Proteomic, transcriptomic, and network pharmacology analyses suggested that Tanshinone IIA may offer therapeutic benefits for PF by mitigating oxidative stress damage via the MAPK signaling pathway. In vitro studies demonstrated that BLM treatment in A549 cells induced exposure of the N‐terminal end of the pyroptosis core protein GSDMD, and elevated oxidative stress levels in A549 cells, concomitant with the upregulation of P‐ERK protein expression. Subsequent administration of Tanshinone IIA, NAC, and U0126 reduced the number of A549 cells undergoing pyroptosis, decreased oxidative stress levels, and decreased P‐ERK protein expression. These findings suggested that Tanshinone IIA potentially delays the progression of PF. The mechanism of action involves the inhibition of oxidative stress and reduced epithelial cell pyroptosis via the MAPK‐related pathway. The findings may provide a new reference for treatment of PF.

Biocontrol of plant pathogens by Lysobacter enzymogenes isolate LEC: efficacy of shake flask broth, fermentation broth and dried preparations

ABSTRACT The aim of our study was to upscale the production of Lysobacter enzymogenes strain LEC from shake flasks to a laboratory bioreactor. The obtained fermentation broth was to be downstream-processed by lyophilisation and fluidised bed-drying, followed by testing of the dried preparations against plant pathogens. Different batches of broth from shake flasks and from individual fermenter runs were characterised and compared. Number of viable cells, in vitro efficacy (ED90 value) against the apple scab pathogen Ventura inaequalis, as well as efficacy against Phytophthora infestans on potato plants were all reproducible and not impaired by upscaling the production volume from shake flask to the bioreactor. Fermentation broth was processed by lyophilisation and fluidised bed-drying. In bioassays, the activity against downy mildew (Pseudoperonospora cubensis) on cucumber were comparable for the unformulated fermentation broth and the fluidised bed-dried product, while the lyophilised product was significantly more effective. Strain LEC showed reproducible pathogen suppressive activity, independent from production scale and batch. Production upscaling and formulation by drying are possible without loss of efficacy.

Grape seed oil attenuates sodium arsenite-induced gastric, hepatic and colonic damage in Wistar rats

ABSTRACT Arsenic exposure is associated with numerous morbidities due to dysfunction of various organ systems including the gastrointestinal tract. We investigated the protective effect of grape seed oil (GSO) against sodium arsenite (NaAsO2)-induced gastric, hepatic and colonic injuries in rats. Twenty-four male Wistar rats were divided into four groups of six as follows: Group A (control) received saline; group B received NaAsO2 (2.5 mg/kg) orally for 7 days; group C were treated concurrently with NaAsO2 and GSO (2 ml/kg), while group D received only GSO. Administration of NaAsO2 induced significant (p < 0.05) increases in alanine aminotransferase (ALT) and aspartate aminotransferase (AST); increased periodic acid Schiff (PAS) staining for mucus and increased goblet cell numbers in the stomach and colon; inflammatory cell infiltration and vascular congestion and alterations in the fecal bacterial flora. GSO supplementation generally promoted a reversal of changes induced by NaAsO2 towards control levels. Additionally, there was increased immunohistochemically detected expression of colonic B-cell lymphoma-1 (Bcl-2) and cytokeratins AE1/AE3, but reduced expression of mucin 1 (MUC1) and carcinoembryonic antigen (CEA) in NaAsO2 + GSO and GSO treated rats when compared with the NaAsO2 group. These results suggest that GSO promoted anti-inflammatory processes in the liver, stomach and colon, as well as opposing apoptosis in the colon, resulting in significant attenuation of damage to these tissues.

Influence of saponin tauroside Sx1 on lifespan and expression of vitamin D receptors in the liver tissue of mice with influenza infection

Introduction. Respiratory infections, including influenza, are often accompanied by hepatitis in humans which pathogenesis is not fully understood. According to the available datan D deficiency is presumably a risk factor in the occurrence of acute respiratory viral infections due to its modulation of immune response. Recent studies indicate that several plant compounds can interact with vitamin D receptors (VDRs) and modulate the activity of VDRs. The biologically active components saponins have found widespread use in clinical practice due to their wide range of biological and pharmacological effects which mechanisms are still largely unclear.Aim. To study the effect of oral administration of saponin tauroside Sx1, obtained from Crimean ivy, on life expectancy and activation of vitamin D receptors in the liver of mice during experimental viral infection of varying severity.Materials and methods. The 11 subgroups were formed from male BALB/c mice, were used in the experiment depending on the infectious dose of influenza virus, 5 LD50 virus or 10 LD50 virus, respectively, including control. Saponin tauroside Sx1 was used as a corrector. Immunohistochemical studies were carried out automatically in a BOND-MAX immunohistainer (Leica, Germany). Primary rabbit polyclonal antibodies to the vitamin D receptor were used.Results and discussion. Due to the administration of tauroside Sx1 at a dose of 200 μg/mouse/day increases the average life expectancy of animals receiving saponin by 4.6 days. Reducing the infectious dose of IV from 10 LD50 to 5 LD50 also changed the onset of death of animals by 2 days in both groups. With different infectious doses of the virus, on the 10th day of the experiment in the subgroups, the expression of vitamin D receptors changes without correction. In subgroup 2V, the number of total positive cells was lower than the control group. Moreover, in the 2Vir subgroup, VDR expression was significantly higher than the control group.Conclusion. The saponin tauroside Sx1 at a dose of 200 µg/mouse/day has a fairly pronounced antiviral effect during experimental infection of mice with the influenza A/H1N1 virus, which is manifested by an increase in the average life expectancy of animals (for 4.6 days) and a decrease in the mortality rate during severe influenza infection, compared with the control group, where 100 % mortality was observed by the 14th day of the experiment. The introduction of saponin on the 4th day of the experiment in all subgroups reduces the total number of immune cells that intensively express VDR.

The Role of FLT3-ITD Mutation, PI3K/AKT Pathway, and Leukemia Stem Cells in D3A7 Induction therapy – the Outcomes of Adult Indonesian Patients with Acute Myeloid Leukemia

Objective. This cohort study aimed to examine the impact of the FLT3-ITD mutation on the downstream signaling pathway of PI3K/AKT pathway, the percentage of leukemia stem cells, and the survival of patients receiving D3A7 induction therapy. Method. Bone marrow mononuclear cells were collected from 20 adult AML patients who had completed D3A7 induction therapy at Cipto Mangunkusumo National General Hospital and Dharmais Cancer Hospital. FLT3-ITD gene mutation was examined by the PCR-sequencing method. Expression of phosphorylated PI3K and AKT was detected using the sandwich ELISA method. Flow cytometry was used for detecting the number of apoptosis and proliferation cells, and biomarkers of leukemia stem cells. Result. The expression levels of PI3K and AKT proteins were higher in FLT3-ITD, both in the mutant group compared to the non-mutation group, and in the patient group with treatment failure outcomes compared to the patient group with treatment response. The percentage of the leukemia stem cell population did not differ significantly between the FLT3-ITD mutation group and the wild type group, and between the treatment failure outcome group and the response outcome group. Conclusion. This study presents the important role of FLT3-ITD mutation via its downstream signaling (PI3K/AKT) in the outcome of D3A7 induction therapy. The FLT3-ITD mutation plays an important role in the 12-month survival of AML patients after D3A7 therapy. However, the outcome of D3A7 therapy and FLT3-ITD mutation were not associated with leukemia stem cells.

Immune cell changes in Helicobacter pylori infection-induced glandular epithelial cell damage of the gastric mucosa

Objective The purpose of this study was to investigate the relationship between Helicobacter pylori (H. pylori) infection-induced changes in gastric mucosal immune cells and glandular epithelial cell damage and the histopathological characteristics of these changes. Methods We performed a detailed histomorphometry and immunohistochemical analysis of a total of 1635 H. pylori-infected gastric mucosal specimens. Results Stage-wise features were as follows: Early stage of infection: H. pylori was colonized in the mucous layer, and very few neutrophils were visible in the layer. Gastric surface epithelial cell infection stage: H. pylori specifically and selectively adhered to the cytoplasm of the surface mucous cells, with the presence of a small number of neutrophils, eosinophils, and lymphocytes infiltration, which is termed early immune response. Compensatory mucous neck cell hyperplasia stage: proliferation of stem cells in the deep gastric pit and infiltration of a large number of lymphocytes in the superficial layer of lamina propria were observed, which is termed immune cell mobilization counterinsurgency. Lamina propria lesion stage: excessive upward migration of the proliferative area. Infiltration of a large number of lymphocytes, plasma cells, monocytes, macrophages, and other immune cells was observed in the whole layer of the gastric mucosa, which is termed automatic replication of immune cells. Abnormal proliferative transformation stage: presence of intranuclear milky globular body cells or signet-ring cell-like heterotypic cells at the junction of the gastric pit and the gastric gland, with proliferation of large numbers of immune cells and vacuolar degeneration of immune cells, which is termed the proliferation and degeneration of immune cells. Intraepithelial neoplasia stage: clonal hyperplasia of epithelial cells and immunosuppression. Conclusion For controlling the occurrence and development of gastric cancer and effective immune intervention, it is essential to grasp the relationship between H. pylori infection-induced changes in gastric mucosal immune cells and glandular epithelial cell damage and its histopathological characteristics.

Deep learning method for detecting fluorescence spots in cancer diagnostics via fluorescence in situ hybridization

Fluorescence in Situ Hybridization (FISH) is a technique for macromolecule identification that utilizes the complementarity of DNA or DNA/RNA double strands. Probes, crafted from selected DNA strands tagged with fluorophore-coupled nucleotides, hybridize to complementary sequences within the cells and tissues under examination. These are subsequently visualized through fluorescence microscopy or imaging systems. However, the vast number of cells and disorganized nucleic acid sequences in FISH images present significant challenges. The manual processing and analysis of these images are not only time-consuming but also prone to human error due to visual fatigue. To overcome these challenges, we propose the integration of medical imaging with deep learning to develop an automated detection system for FISH images. This system features an algorithm capable of quickly detecting fluorescent spots and capturing their coordinates, which is crucial for evaluating cellular characteristics in cancer diagnosis. Traditional models struggle with the small size, low resolution, and noise prevalent in fluorescent points, leading to significant performance declines. This paper offers a detailed examination of these issues, providing insights into why traditional models falter. Comparative tests between the YOLO series models and our proposed method affirm the superior accuracy of our approach in identifying fluorescent dots in FISH images.

Adamts1 and Cyst Expansion in Polycystic Kidney Disease

Background: Autosomal dominant polycystic kidney disease (ADPKD) is characterized by mutations in either the Pkd1 or Pkd2 genes leading to progressive cyst growth and often kidney failure. We have previously demonstrated that tubules can enlarge following loss of Pkd1 without an increase in tubular cell numbers, suggesting that tubular basement membrane remodeling is important for cystic dilation. RNA sequencing of Pkd1 null kidneys revealed increased expression of 17 metalloproteinases, of which A Disintegrin and Metalloproteinase with Thrombospondin Motif 1 (Adamts1) is the most highly expressed and upregulated. Methods: Mice were generated with inducible tubule-specific knockout of Adamts1 alone (AtsTKO), Pkd1 alone (PkdTKO), or both (P/ATKO) following doxycycline induction from 4-6 weeks age. Uninduced mice were used as controls. AtsTKO mice had no detectable phenotype through 12 weeks age. Results: Upregulation of Adamts1 in PkdTKO kidneys correlated with a significant increase in the 70 kDa cleavage product of the V1 isoform of versican, which localized to the tubular basement membrane and adjacent interstitial mononuclear cells. Simultaneous deletion of both Adamts1 and Pkd1 (P/ATKO) reduced Adamts1 expression levels by &gt;90%, prevented V1 versican cleavage, and reduced interstitial macrophage accumulation and activation. P/ATKO mice demonstrated reduced cystic enlargement, improved BUN and creatinine and better survival than did PkdTKO mice. Conclusions: Preventing Adamts1 upregulation following loss of tubular Pkd1 effectively reduced cyst growth and preserved kidney function.

Severe herpes simplex virus − 1 Kaposi varicelliform eruption and SARS-CoV-2 infection in atopic dermatitis treated with dupilumab

Herpes Simplex Virus-1 (HSV-1) Kaposi varicelliform eruption (KVE) is a rare and severe cutaneous manifestation, clinically characterized by the presence of widespread vesicles and pustules. A case report details a patient with a history of Atopic Dermatitis (AD) and recent SARS-CoV-2 infection who developed a severe KVE subsequent to the viral illness. The patient, a 35-year-old male, presented with severe atopic dermatitis (AD) subsequent to a SARS-CoV-2 infection. In a period of four months, the dermatological eruption underwent a rapid progression to a severe state, characterised by the presence of extensive vesicles and pustules, in addition to the emergence of symptoms. In conjunction with a chest CT scan, plasma and antigen testing, the patient was confirmed to be positive for HSV-1 positive. The patient exhibited elevated levels of IgE and a notable reduction in the absolute number of immune cells. The patient was treated with valaciclovir, piperacillin-tazobactam, IVIG at the same time. Within seven days of treatment, the blisters had dried up and the scabs had fallen off without any pain, pruritus, or fever. This case highlights the potential for severe viral eruptions, such as KVE in individuals with underlying dermatological conditions following viral infections.

Aerodynamic optimisation of flat-upper-surface wing

Purpose The paper aims to optimise several concepts of the flat-upper-surface wing that could install the largest possible number of photovoltaic cells and test them in flight. A wing ideal flat upper surface was necessary to provide the same lighting conditions for each tested cell. Design/methodology/approach The optimised wings were built based on a developed family of airfoils having 75% of their upper surface flat. Within the developed parametric model of the wings, the design parameters described the spanwise distribution of base airfoils. Maximisation of the endurance factor was assumed as the main objective. The aerodynamic properties of optimised wings were evaluated using a panel method coupled with boundary layer analysis. Findings The paper proves that it is possible to design wings with 75% of their upper surface perfectly flat, which are also characterised by good aerodynamic properties. Practical implications The research conducted will allow designing an experimental unmanned aerial vehicle dedicated to investigating the properties of electrical propulsion systems at various altitudes. Data obtained in these investigations will help in the development of future generations of electric-propulsion aircraft. Originality/value The innovative wings, developed within the research are unique due to their unusual geometric and aerodynamic properties. They have 75% of their upper surface perfectly flat. That makes them ideal for testing various photovoltaic cells in flight. The biggest challenge was to design the wings so that their specific geometric features did not impair their aerodynamic properties. The paper proves that this challenge has been fully overcome.

Production of Oncolytic Measles Virus in Vero Cells: Impact of Culture Medium and Multiplicity of Infection

Oncolytic measles virus (MeV) is a promising anti-cancer treatment. However, the production of high titers of infectious MeV (typically 107–109 TCID50 per dose) is challenging because the virus is unstable under typical production conditions. The objective of this study was to investigate how the multiplicity of infection (MOI) and different media—a serum-containing medium (SCM), a serum-free medium (SFM) and two chemically defined media (CDM)—affect MeV production. We infected Vero cells at MOIs of 0.02, 0.2 or 2 TCID50 mL−1 and the lowest MOI resulted in the largest number of infected cells towards the end of the production period. However, this did not equate to higher maximum MeV titers, which were similar for all the MOIs. The medium had a moderate effect, generating maximum titers of 0.89–2.17 × 106, 1.08–1.25 × 106 and 4.58–9.90 × 105 TCID50 mL−1 for the SCM, SFM and CDM, respectively. Infection at a low MOI often required longer process times to reach maximum yields. On the other hand, a high MOI requires a large amount of MeV stock. We would therefore recommend a mid-range MOI of 0.2 TCID50 mL−1 for MeV production. Our findings show that SCM, SFM and CDM are equally suitable for MeV production in terms of yield and process time. This will allow MeV production in serum-free conditions, addressing the safety risks and ethical concerns associated with the use of serum.

Coordinated inheritance of extrachromosomal DNAs in cancer cells

The chromosomal theory of inheritance dictates that genes on the same chromosome segregate together while genes on different chromosomes assort independently1. Extrachromosomal DNAs (ecDNAs) are common in cancer and drive oncogene amplification, dysregulated gene expression and intratumoural heterogeneity through random segregation during cell division2,3. Distinct ecDNA sequences, termed ecDNA species, can co-exist to facilitate intermolecular cooperation in cancer cells4. How multiple ecDNA species within a tumour cell are assorted and maintained across somatic cell generations is unclear. Here we show that cooperative ecDNA species are coordinately inherited through mitotic co-segregation. Imaging and single-cell analyses show that multiple ecDNAs encoding distinct oncogenes co-occur and are correlated in copy number in human cancer cells. ecDNA species are coordinately segregated asymmetrically during mitosis, resulting in daughter cells with simultaneous copy-number gains in multiple ecDNA species before any selection. Intermolecular proximity and active transcription at the start of mitosis facilitate the coordinated segregation of ecDNA species, and transcription inhibition reduces co-segregation. Computational modelling reveals the quantitative principles of ecDNA co-segregation and co-selection, predicting their observed distributions in cancer cells. Coordinated inheritance of ecDNAs enables co-amplification of specialized ecDNAs containing only enhancer elements and guides therapeutic strategies to jointly deplete cooperating ecDNA oncogenes. Coordinated inheritance of ecDNAs confers stability to oncogene cooperation and novel gene regulatory circuits, allowing winning combinations of epigenetic states to be transmitted across cell generations.

SMN depletion impairs skeletal muscle formation and maturation in a mouse model of SMA.

Spinal muscular atrophy (SMA) is characterized by low levels of the ubiquitously expressed Survival Motor Neuron (SMN) protein, leading to progressive muscle weakness and atrophy. Skeletal muscle satellite cells play a crucial role in muscle fiber maintenance, repair, and remodelling. While the effects of SMN depletion in muscle are well documented, its precise role in satellite cell function remains largely unclear. Using the Smn2B/- mouse model, we investigated SMN-depleted satellite cell biology through single fiber culture studies. Myofibers from Smn2B/- mice were smaller in size, shorter in length, had reduced myonuclear domain size, and reduced sub-synaptic myonuclear clusters-all suggesting impaired muscle function and integrity. These changes were accompanied by a reduction in the number of myonuclei in myofibers from Smn2B/- mice across all disease stages examined. Although the number of satellite cells in myofibers was significantly reduced, those remaining retained their capacity for myogenic activation and proliferation. These findings support the idea that a dysregulated myogenic process could be occurring as early in muscle stem cells during muscle formation and maturation in SMA. Targeting those pathways could offer additional options for combinatorial therapies for SMA.

Inhibitory Effect of DNase–Chitosan–Nisin Nanoparticles on Cell Viability, Motility, and Spatial Structures of Listeria monocytogenes Biofilms

Listeria monocytogenes biofilm contamination on food contact surfaces is a major concern for the food industry. Nanoparticle encapsulation appears as a novel strategy for food surface disinfection to prevent biofilm formation. Chitosan nanoparticles loaded with nisin and DNase I (DNase-CS-N) have been constructed to exhibit antimicrobial activity against L. monocytogenes. This study aimed to investigate their ability to inhibit L. monocytogenes biofilm formation and eliminate preformed biofilms on food contact surfaces (polystyrene, polyurethane, and stainless steel). DNase-CS-N could decrease 99% and 99.5% biofilm cell numbers at 1/2 MIC and MIC, respectively. At sub-MICs, DNase-CS-N could reduce cell motility (swimming and swarming) and slime production of L. monocytogenes. In terms of effect on biofilm elimination, DNase-CS-N at the concentration of 4 MIC led to 3–4 log reduction in biofilm cells in preformed biofilms, performing higher efficiency compared with other treatments (CSNPs, CS-N). Furthermore, the three-dimensional structure of L. monocytogenes biofilms was severely disrupted after DNase-CS-N treatment, with bacterial cells scattered on the surface. The morphology of biofilm cells was also greatly damaged with wrinkled surfaces, disrupted cell membranes, and leakage of intracellular nucleic acids and proteins. These results indicate the potential applicability of DNase-CS-N for inhibiting and eliminating L. monocytogenes biofilms on food contact surfaces.

Patient-Derived Organoids on a Microarray for Drug Resistance Study in Breast Cancer.

Drug resistance is always a challenge in cancer treatment, whether for chemotherapy, targeting, or immunotherapy. Although tumor cell lines are derived from cancer patients, they gradually lost the original characteristics, including heterogeneity and tumor microenvironment (TME), during the long period of in vitro culturing. Therefore, it is urgent to use patient-derived tumor models instead of cancer cell lines to study tumor drug resistance. Herein, we developed a microarray device that serves as a platform for high-throughput and three-dimensional culture of breast cancer patient-derived organoids (BCOs) and investigated their resistance to adriamycin (ADM). Coupled with fluorescence microscopy, this system enabled on-chip drug response monitoring and cell viability assessment without the consumption of a large number of tumor cells. The organoids were divided into a resistant BCO group (RBCO) and a sensitive BCO group (SBCO) according to their half-inhibitory concentration (IC50). Different from cancer cell lines, BCOs demonstrated obvious heterogeneity in drug treatment. Ivermectin (IVM), a broad-spectrum antiparasitic agent approved by the Food and Drug Administration (FDA), was observed to synergistically augment ADM-induced cytotoxicity in organoids. The BCO chip provides a promising platform for investigation of drug resistance and preclinical drug screening based on clinical samples.

Quantifying Mast Cell and Eosinophil Cellular Density in Skin Biopsy Tissue From Adults With Maculopapular Cutaneous Mastocytosis as Compared With Urticaria and Normal Skin: A Retrospective Histopathologic Study.

Maculopapular cutaneous mastocytosis (MPCM) is a rare disorder characterized by a pathologic accumulation of mast cells in the skin, which may or may not be accompanied by systemic mastocytosis. Diagnosis of MPCM on skin biopsy can be challenging because the findings may be subtle. Although mast cell density in MPCM has been reported, data informing a proposed cutoff for diagnosis and diagnostic criteria are limited. We identified adult patients diagnosed with MPCM and urticarial tissue reaction/chronic urticaria on skin biopsy and compared the mast cell and eosinophil counts per 1 mm2 in 10 cases each of MPCM, chronic urticaria, and normal skin from routine biopsies. All slides were stained with CD117, and CD117-positive mast cells were counted per 1 mm2 using digital microscopy. Eosinophils were counted on hematoxylin and eosin-stained slides per 1 mm2 using digital microscopy. The median number of mast cells per 1 mm2 was significantly higher in MPCM than in cases of urticaria and normal skin/control tissue (177.3 vs. 26.8 vs. 47.8 mast cell per mm2, respectively; P ≤ 0.001). The calculated "cut point" for mastocytosis versus chronic urticaria and normal skin was 66 mast cells per 1 mm2, whereas the value for controls versus urticaria was 37 mast cells per 1 mm2. Eosinophils had similar density in MPCM and urticaria, and their presence was significant in the differentiation of MPCM and urticaria from normal tissue. This study adds to the literature by providing objective mast cell density data to distinguish challenging cases of cutaneous mastocytosis from urticarial reactions and normal skin. Future studies could explore the development of computer-aided estimations of cellular density with more extensive comparison with other inflammatory conditions to translate our findings more readily into clinical practice.

Developmental encoding of natural sounds in the mouse auditory cortex.

Mice communicate through high-frequency ultrasonic vocalizations, which are crucial for social interactions such as courtship and aggression. Although ultrasonic vocalization representation has been found in adult brain areas along the auditory pathway, including the auditory cortex, no evidence is available on the neuronal representation of ultrasonic vocalizations early in life. Using in vivo two-photon calcium imaging, we analyzed auditory cortex layer 2/3 neuronal responses to USVs, pure tones (4 to 90kHz), and high-frequency modulated sweeps from postnatal day 12 (P12) to P21. We found that ACx neurons are tuned to respond to ultrasonic vocalization syllables as early as P12 to P13, with an increasing number of responsive cells as the mouse age. By P14, while pure tone responses showed a frequency preference, no syllable preference was observed. Additionally, at P14, USVs, pure tones, and modulated sweeps activate clusters of largely nonoverlapping responsive neurons. Finally, we show that while cell correlation decreases with increasing processing of peripheral auditory stimuli, neurons responding to the same stimulus maintain highly correlated spontaneous activity after circuits have attained mature organization, forming neuronal subnetworks sharing similar functional properties.