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Nature Communications May 2024Magnetic field-induced changes in the electrical resistance of materials reveal insights into the fundamental properties governing their electronic and magnetic...
Magnetic field-induced changes in the electrical resistance of materials reveal insights into the fundamental properties governing their electronic and magnetic behavior. Various classes of magnetoresistance have been realized, including giant, colossal, and extraordinary magnetoresistance, each with distinct physical origins. In recent years, extreme magnetoresistance (XMR) has been observed in topological and non-topological materials displaying a non-saturating magnetoresistance reaching 10-10% in magnetic fields up to 60 T. XMR is often intimately linked to a gapless band structure with steep bands and charge compensation. Here, we show that a linear XMR of 80,000% at 15 T and 2 K emerges at the high-mobility interface between the large band-gap oxides γ-AlO and SrTiO. Despite the chemically and electronically very dissimilar environment, the temperature/field phase diagrams of γ-AlO/SrTiO bear a striking resemblance to XMR semimetals. By comparing magnetotransport, microscopic current imaging, and momentum-resolved band structures, we conclude that the XMR in γ-AlO/SrTiO is not strongly linked to the band structure, but arises from weak disorder enforcing a squeezed guiding center motion of electrons. We also present a dynamic XMR self-enhancement through an autonomous redistribution of quasi-mobile oxygen vacancies. Our findings shed new light on XMR and introduce tunability using dynamic defect engineering.
PubMed: 38762504
DOI: 10.1038/s41467-024-48398-8 -
Zhong Nan Da Xue Xue Bao. Yi Xue Ban =... Feb 2024Hypoxia is a common pathological phenomenon, usually caused by insufficient oxygen supply or inability to use oxygen effectively. Hydroxylated and methoxylated...
OBJECTIVES
Hypoxia is a common pathological phenomenon, usually caused by insufficient oxygen supply or inability to use oxygen effectively. Hydroxylated and methoxylated flavonoids have significant anti-hypoxia activity. This study aims to explore the synthesis, antioxidant and anti-hypoxia activities of 6-hydroxygenistein (6-OHG) and its methoxylated derivatives.
METHODS
The 6-OHG and its methoxylated derivatives, including 4',6,7-trimethoxy-5-hydroxyisoflavone (compound 3), 4',5,6,7-tetramethoxyisoflavone (compound 4), 4',6-imethoxy-5,7-dihydroxyisoflavone (compound 6), and 4'-methoxy-5,6,7-trihydroxyisoflavone (compound 7), were synthesized by methylation, bromination, methoxylation, and demethylation using biochanin A as raw material. The structure of these products were characterized by hydrogen-nuclear magnetic resonance spectroscopy (H-NMR) and mass spectrometry (MS). The purity of these compounds was detected by high pressure chromatography (HPLC). The antioxidant activity in vitro was investigated by 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) free radical scavenging assay. PC12 cells were divided into a normal group, a hypoxia model group, rutin (1×10-1×10 mol/L) groups, and target compounds (1×10-1×10 mol/L) groups under normal and hypoxic conditions. Cell viability was detected by cell counting kit-8 (CCK-8) assay, the target compounds with excellent anti-hypoxia activity and the drug concentration at the maximum anti-hypoxia activity were screened. PC12 cells were treated with the optimal concentration of the target compound or rutin with excellent anti-hypoxia activity, and the cell morphology was observed under light microscope. The apoptotic rate was determined by flow cytometry, and the expressions of hypoxia inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) were detected by Western blotting.
RESULTS
The structure of 6-OHG and its 4 methylated derivatives were correct, and the purity was all more than 97%. When the concentration was 4 mmol/L, the DPPH free radical removal rates of chemical compounds 7 and 6-OHG were 81.16% and 86.94%, respectively, which were higher than those of rutin, the positive control. The removal rates of chemical compounds 3, 4, and 6 were all lower than 20%. Compared with the normal group, the cell viability of the hypoxia model group was significantly decreased (<0.01). Compared with the hypoxia model group, compounds 3, 4, and 6 had no significant effect on cell viability under hypoxic conditions. At all experimental concentrations, the cell viability of the 6-OHG group was significantly higher than that of the hypoxia model group (all <0.05). The cell viability of compound 7 group at 1×10 and 1×10 mol/L was significantly higher than that of the hypoxia model group (both <0.05). The anti-hypoxia activity of 6-OHG and compound 7 was excellent, and the optimal drug concentration was 1×10 and 1×10 mol/L. After PC12 cells was treated with 6-OHG (1×10 mol/L) and compound 7 (1×10 mol/L), the cell damage was reduced, the apoptotic rate was significantly decreased (<0.01), and the protein expression levels of HIF-1α and VEGF were significantly decreased in comparison with the hypoxia model group (both <0.01).
CONCLUSIONS
The optimized synthesis route can increase the yield of 6-OHG and obtain 4 derivatives by methylation and selective demethylation. 6-OHG and compound 7 have excellent antioxidant and anti-hypoxia activities, which are related to the structure of the A-ring ortho-triphenol hydroxyl group in the molecule.
Topics: Antioxidants; Rats; Animals; PC12 Cells; Methylation; Cell Hypoxia; Vascular Endothelial Growth Factor A; Isoflavones; Flavones
PubMed: 38755719
DOI: 10.11817/j.issn.1672-7347.2024.230228 -
Nature Communications May 2024Computational super-resolution methods, including conventional analytical algorithms and deep learning models, have substantially improved optical microscopy. Among...
Computational super-resolution methods, including conventional analytical algorithms and deep learning models, have substantially improved optical microscopy. Among them, supervised deep neural networks have demonstrated outstanding performance, however, demanding abundant high-quality training data, which are laborious and even impractical to acquire due to the high dynamics of living cells. Here, we develop zero-shot deconvolution networks (ZS-DeconvNet) that instantly enhance the resolution of microscope images by more than 1.5-fold over the diffraction limit with 10-fold lower fluorescence than ordinary super-resolution imaging conditions, in an unsupervised manner without the need for either ground truths or additional data acquisition. We demonstrate the versatile applicability of ZS-DeconvNet on multiple imaging modalities, including total internal reflection fluorescence microscopy, three-dimensional wide-field microscopy, confocal microscopy, two-photon microscopy, lattice light-sheet microscopy, and multimodal structured illumination microscopy, which enables multi-color, long-term, super-resolution 2D/3D imaging of subcellular bioprocesses from mitotic single cells to multicellular embryos of mouse and C. elegans.
Topics: Animals; Caenorhabditis elegans; Microscopy, Fluorescence; Mice; Imaging, Three-Dimensional; Algorithms; Image Processing, Computer-Assisted; Deep Learning
PubMed: 38755148
DOI: 10.1038/s41467-024-48575-9 -
Frontiers in Pharmacology 2024To expand the application of nobiletin (NOB) in semi-solid functional foods, bovine serum albumin (BSA)/carboxymethyl inulin (CMI) complexes-stabilized Pickering...
To expand the application of nobiletin (NOB) in semi-solid functional foods, bovine serum albumin (BSA)/carboxymethyl inulin (CMI) complexes-stabilized Pickering emulsion (BCPE) (φ = 60%, v/v) was fabricated, and the swallowing index and bioavailability of the NOB-loaded Pickering emulsion was evaluated. Confocal laser scanning microscope (CLSM) and cryo-scanning electron microscopy (cryo-SEM) images revealed that BSA/CMI complexes attached to the oil-water interface. NOB-loaded BCPE exhibited a viscoelastic and shear-thinning behavior. Fork drip test results suggested that the textural value of unloaded and NOB-loaded emulsions was International Dysphagia Diet Standardisation Initiative Level 4, which could be swallowed directly without chewing. The lipolysis model suggested that NOB had a faster digestive profile and a higher bioaccessibility in the BCPE than in the oil suspension. The rat model revealed that the oral bioavailability of NOB was increased by 2.07 folds in BCPE compared to its bioavailability in unformulated oil. Moreover, BCPE led to a higher plasma concentration of the major demethylated metabolite of NOB (4'-demethylnobiletin) than the unformulated oil. Accordingly, BCPE enhanced the oral bioavailability of NOB by improving bioaccessibility, absorption, and biotransformation.
PubMed: 38751784
DOI: 10.3389/fphar.2024.1375779 -
American Journal of Kidney Diseases :... May 2024Light and heavy chain deposition disease (LHCDD) is a rare form of monoclonal immunoglobulin deposition disease (MIDD), and limited clinical data are available...
RATIONALE & OBJECTIVE
Light and heavy chain deposition disease (LHCDD) is a rare form of monoclonal immunoglobulin deposition disease (MIDD), and limited clinical data are available characterizing this condition. We described the clinicopathological characteristics and outcomes of LHCDD.
STUDY DESIGN
Case series.
SETTING & PARTICIPANTS
13 patients with biopsy-proven LHCDD, diagnosed between January 2008 to December 2022, at two Chinese medical centers.
FINDINGS
Among the 13 patients described, 6 were men and 7 were women, with a mean age of 52.6 ± 8.0 years. Patients presented with hypertension (76.9%), anemia (84.6%), elevated serum creatinine (84.6%, median serum creatinine 1.7 mg/dL), proteinuria (100%, average urine protein 3.0g/24h), nephrotic syndrome (30.8%) and microscopic hematuria (76.9%). Serum immunofixation electrophoresis showed monoclonal immunoglobulin for 11 (84.6%) patients. Serum free light chain (FLC) ratios were abnormal in 11 (84.6%) patients, and heavy/light chain (HLC) ratios were abnormal in 9 of 10 (90%) patients with available data. Five patients were diagnosed with multiple myeloma. A histological diagnosis of nodular mesangial sclerosis was made in 10 (76.9%) patients. Immunofluorescence demonstrated deposits of IgG subclass (γ-κ/γ-λ:4/3) in 7 patients, and IgA (α-κ/α-λ:2/3) in 5 patients. Six patients underwent IgG subclass staining (γ1/γ2/γ3:3/2/1). The deposits of IgD-κ were confirmed by mass spectrometry in 1 patient. Among 12 patients for whom data were available over a median of 26.5 months, 11 received chemotherapy, and 1 received conservative treatment. One patient died. Three (25%) patients progressed to kidney failure. Among the 9 patients evaluable for hematological and kidney disease progression, five (56%) had a hematologic response and one (11%) achieved improvement in kidney disease.
LIMITATIONS
Retrospective descriptive study, limited number of patients, UPEP or UIFE missing for most patients.
CONCLUSIONS
In this case series of LHCDD, light and heavy chain deposition in kidney tissues were most frequent with monoclonal IgG1-κ. Among patients with evaluable data, more than half had hematologic response but a kidney response was uncommon.
PubMed: 38750878
DOI: 10.1053/j.ajkd.2024.03.021 -
Brazilian Oral Research 2024Dental pulp stem cells (DPSCs) and periodontal ligament stem cells (PDLSCs) can differentiate into osteoblasts, indicating that both are potential candidates for bone...
Dental pulp stem cells (DPSCs) and periodontal ligament stem cells (PDLSCs) can differentiate into osteoblasts, indicating that both are potential candidates for bone tissue engineering. Osteogenesis is influenced by many environmental factors, one of which is lipopolysaccharide (LPS). LPS-induced NF-κB activity affects the osteogenic potencies of different types of MSCs differently. This study evaluated the effect of LPS-induced NF-κB activity and its inhibition in DPSCs and PDLSCs. DPSCs and PDLSCs were cultured in an osteogenic medium, pretreated with/without NF-κB inhibitor Bay 11-7082, and treated with/without LPS. Alizarin red staining was performed to assess bone nodule formation, which was observed under an inverted light microscope. NF-κB and alkaline phosphatase (ALP) activities were measured to examine the effect of Bay 11-7082 pretreatment and LPS supplementation on osteogenic differentiation of DPSCs and PDLSCs. LPS significantly induced NF-κB activity (p = 0.000) and reduced ALP activity (p = 0.000), which inhibited bone nodule formation in DPSCs and PDLSCs. Bay 11-7082 inhibited LPS-induced NF-κB activity, and partially maintained ALP activity and osteogenic potency of LPS-supplemented DPSCs and PDLSCs. Thus, inhibition of LPS-induced NF-κB activity can maintain the osteogenic potency of DPSCs and PDLSCs.
Topics: Humans; Lipopolysaccharides; Periodontal Ligament; Osteogenesis; Dental Pulp; NF-kappa B; Alkaline Phosphatase; Cell Differentiation; Stem Cells; Cells, Cultured; Nitriles; Sulfones; Reproducibility of Results; Time Factors; Young Adult; Adolescent
PubMed: 38747824
DOI: 10.1590/1807-3107bor-2024.vol38.0037 -
Acta Otorhinolaryngologica Italica :... May 2024To evaluate the efficacy of transoral laser exoscopic surgery (TOLES) in a unicentric series of patients affected by benign and malignant glottic and supraglottic... (Comparative Study)
Comparative Study
OBJECTIVE
To evaluate the efficacy of transoral laser exoscopic surgery (TOLES) in a unicentric series of patients affected by benign and malignant glottic and supraglottic lesions, and compare outcomes with those of transoral laser microsurgery (TOLMS).
METHODS
To demonstrate the non-inferiority of TOLES in terms of operative time, margin status and complication rates, we compared outcomes of 93 patients treated by TOLES between July 2021 and July 2023 with those of a match-paired group of 107 historical patients treated by TOLMS. To perform a multiparametric ergonomic evaluation of TOLES TOLMS, we used observational methods for biomechanical overload risk assessment and wearable technologies comparing 15 procedures with TOLES a paired match of 13 surgeries performed with TOLMS by the same surgeon.
RESULTS
No significant differences were found in terms of surgical duration, positive margins, or complications between TOLES and TOLMS. Ergonomics assessment by inertial measurement units and electromyographic surface electrodes demonstrated a reduced biomechanical overload with TOLES compared to TOLMS.
CONCLUSIONS
The many advantages of TOLES, such as its superior didactic value, better digital control of light even through small-bored laryngoscopes, improved binocular vision, and increase in surgical performance by 3 or 4-hand techniques, are difficult to be quantified. In contrast, its non-inferiority in terms of oncological results and better ergonomics compared to TOLMS are demonstrated herein.
Topics: Humans; Microsurgery; Laser Therapy; Male; Female; Middle Aged; Aged; Mouth; Laryngeal Neoplasms; Treatment Outcome; Natural Orifice Endoscopic Surgery; Ergonomics; Adult; Larynx
PubMed: 38745511
DOI: 10.14639/0392-100X-suppl.1-44-2024-N2850 -
BMC Urology May 2024Microplastics are ubiquitous, widespread environmental pollutants with unavoidable human exposure. Herein, it was aimed to investigate the presence of microplastics in...
BACKGROUND
Microplastics are ubiquitous, widespread environmental pollutants with unavoidable human exposure. Herein, it was aimed to investigate the presence of microplastics in prostate tissue.
METHODS
Prostate tissues from 12 patients who underwent Trans Urethral Resection of the Prostate (TUR-P) were analyzed to investigate the presence of microplastics. Initially, the prostate tissues were analyzed for microplastic particles using a light microscope after extraction. Subsequently, the chemical composition of the particles found in the prostate tissues was characterized using Attenuated Total Reflection-Fourier Transform Infrared (ATR-FTIR) spectrophotometry.
RESULTS
Microplastic particles of various types were detected in 6 out of 12 patients. All detected plastic particles in this study were microplastics, with sizes below 26 μm in size. These microplastics exhibited different shapes as pellets, spheres or fibers. Overall, among the 12 analyzed prostate tissue samples, four different types of plastic were identified in six samples. The most common type of microplastic detected was Polyamide (Nylon 6), found in samples from three patients. Other detected types, Polypropylene, Polyacrylic Acid and Poly (dimethylsiloxane) were each determined in samples from one patient.
CONCLUSIONS
This is the first study to demonstrate the presence of microplastics in prostate tissue, serving as an exploratory investigation, which can trigger further research to validate the results in a larger patient cohort.
Topics: Humans; Male; Microplastics; Prostate; Aged; Middle Aged
PubMed: 38745203
DOI: 10.1186/s12894-024-01495-8 -
Proceedings of SPIE--the International... 2024Zebrafish is a well-established animal model for developmental and disease studies. Its optical transparency at early developmental stages is ideal for tissue...
Zebrafish is a well-established animal model for developmental and disease studies. Its optical transparency at early developmental stages is ideal for tissue visualization. Interaction of light with zebrafish tissues provides information on their structure and properties. In this study, we developed a microscopic imaging system for improving the visualization of unstained zebrafish tissues on tissue slides, with two different setups: polarized light imaging and polarized hyperspectral imaging. Based on the polarized light imaging setup, we collected the RGB images of Stokes vector parameters (S0, S1, S2, and S3), and calculated the Stokes vector derived parameters: the degree of polarization (DOP), the degree of linear polarization (DOLP)). We also calculated Stokes vector data based on the polarized hyperspectral imaging setup. The preliminary results demonstrate that Stokes vector data in two imaging setups (polarized light imaging and polarized hyperspectral imaging) are capable of improving the visualization of different types of zebrafish tissues (brain, muscle, skin cells, blood vessels, and yolk). Using the images collected from larval zebrafish samples by polarized light imaging, we found that DOP and DOLP could show clearer structural information of the brain and of skin cells, muscle and blood vessels in the tail. Furthermore, DOP and DOLP parameters derived from images collected by polarized hyperspectral imaging could show clearer structural information of skin cells developing around yolk as well as the surrounding blood vessel network. In addition, polarized hyperspectral imaging could provide complementary spectral information to the spatial information on Stokes vector data of zebrafish tissues. The polarized light imaging & polarized hyperspectral imaging systems provide a better insight into the microstructures of zebrafish tissues.
PubMed: 38737328
DOI: 10.1117/12.3007294 -
Materials Today. Bio Jun 2024Although 2D cancer models have been the standard for drug development, they don't resemble properties adequately. 3D models can potentially overcome this. Bioprinting...
Although 2D cancer models have been the standard for drug development, they don't resemble properties adequately. 3D models can potentially overcome this. Bioprinting is a promising technique for more refined models to investigate central processes in tumor development such as proliferation, dormancy or metastasis. We aimed to analyze bioinks, which could mimic these different tumor stages in a cast vascularized arteriovenous loop melanoma model . It has the advantage to be a closed system with a defined microenvironment, supplied only with one vessel-ideal for metastasis research. Tested bioinks showed significant differences in composition, printability, stiffness and microscopic pore structure, which led to different tumor stages (Matrigel and Alg/HA/Gel for progression, Cellink Bioink for dormancy) and resulted in different primary tumor growth (Matrigel significantly higher than Cellink Bioink). Light-sheet fluorescence microscopy revealed differences in vascularization and hemorrhages with no additional vessels found in Cellink Bioink. Histologically, typical human melanoma with different stages was demonstrated. HMB-45-positive tumors in progression inks were infiltrated by macrophages (CD163), highly proliferative (Ki67) and metastatic (MITF/BRN2, ATX, MMP3). Stainings of lymph nodes revealed metastases even without significant primary tumor growth in Cellink Bioink. This model can be used to study tumor pathology and metastasis of different tumor stages and therapies.
PubMed: 38736612
DOI: 10.1016/j.mtbio.2024.101071