Microscopy and Microanalysis最新文献

The pituitary gland is the primary endocrine gland, consisting of many cell types in its anterior region that regulate crucial physiological processes like development, maturation, metabolism, reproduction, stress response, and aging. This study aims to investigate and compare anatomical, histological, and histochemical variations between young and adult female pituitary glands of Rhinopoma hardwickii. The pituitary gland of ten healthy young and adult R. hardwickii has been used. Histological findings indicated that the gland in adult bats was irregular, whereas in young bats it was semicircular. Three types of cells appeared: acidophilic, basophilic, and chromophobic, which were unevenly distributed across the gland's body. Histochemically, chromophilic cells reacted positively with PAS and Alcian blue-PAS-Orange G stains. Also, using Masson's Trichrome stain, collagen fibers between the cells of adenohypophysis and in the capsule surrounding the gland gave a blue color. This study revealed several similarities as well as certain variations in the external shape of the anterior pituitary cells and their distribution pattern in both stages may be attributed to age-related developmental and physiological changes. Furthermore, the hormone cells of the anterior Pituitary were extensively specialized and became dedicated at after birth illustrating evolutionary adaptations to endocrine regulation.

Quantitative potential retrieval in scanning transmission electron microscopy (STEM) is of much importance for detailed material characterization but is often hindered by substantial multiple scattering effects in thicker samples. Here, we propose a gradient-descent-based optimization algorithm to obtain the quantitative potential from thick samples from a four-dimensional (4D) STEM dataset using the scattering matrix (S-matrix), which is an operator to calculate the exit-surface wavefunction in the presence of multiple scattering. This optimization uses optimum bright-field STEM data as an initial guess of potential and a loss function based on measured and estimated 4D STEM datasets without the regularization terms commonly used in iterative potential retrieval techniques in STEM. We show the capabilities of our approach through systematic simulations across a range of sample thicknesses, doses, and degrees of spatial incoherence and by applying it to experimental data. The extension of our algorithm from pixelated to segmented detectors is also investigated.

In this study, light microscopy and scanning electron microscopy (SEM) were employed to investigate morphological and structural characteristics of otoliths (ear stones) in garfish Belone belone individuals (n = 190) collected from the Kocaeli (n = 114) and Ordu (n = 76) coasts of the Black Sea. SEM analyses enabled high-resolution imaging of otolith surface microstructures and revealed clear morphological deviations in a subset of specimens. Otolith abnormalities were observed in nine individuals, with a regional frequency of 3.5% in Kocaeli and 6.58% in Ordu. While normal otoliths displayed consistent aragonite crystal patterns and elliptical morphology with defined mesial and lateral surfaces, abnormal otoliths showed irregular growth patterns, asymmetry, and disrupted surface architecture, particularly on the lateral surface. Morphometric measurements such as length, width, area, perimeter, and weight indicated significant differences between normal and abnormal otoliths (p < 0.05), especially in the Ordu samples. SEM provided detailed evidence of altered biomineralization in abnormal otoliths, suggesting possible environmental or developmental influences. These results highlight the utility of integrated microscopy techniques in identifying subtle structural anomalies and contribute to a deeper understanding of otolith formation and variability in marine teleosts. The combined use of SEM and light microscopy proves essential for comprehensive microstructural characterization in fish biomineral studies.

Insomnia is one of the main manifestations of subhealth, a condition that has become increasingly prevalent and seriously affects the physical and mental well-being of many individuals. This study aims to investigate the effects of γ-aminobutyric acid (GABA)-herbal medicine composite (GABA-HMC) on sleep in both healthy and insomnia-plagued rats. According to traditional Chinese medicine theory, the Du Meridian, situated along the dorsal midline fascia of the body, plays a crucial role in regulating neuropsychiatric disorders, such as insomnia. Recent reports morphologically confirmed that telocytes (TCs) are the key cells of meridian essence. In this experiment, we developed GABA-HMC containing GABA, valerian oil, Hypericum perforatum extract, and ginseng extract. We applied it to the Du Meridian of healthy and insomnia rats and observed the changes in TCs. The results showed that treatment with GABA-HMC significantly increased serotonin content, alleviating insomnia and improving sleep quality. Immunofluorescence and transmission electron microscopy (TEM) further revealed that the application of the cream increased the number of TCs in the subcutaneous fascia, elongated telopodes, and enhanced cell junctions. These results suggest that TCs are the key effector cells of GABA-HMC, providing valuable insights into potential novel approaches for treating insomnia.

Precession of a converged beam during acquisition of a 4D-STEM dataset improves strain, orientation, and phase mapping accuracy by averaging over continuous angles of illumination. Precession experiments usually rely on integrated systems, where automatic alignments lead to fast, high-quality results. The dependence of these experiments on specific hardware and software is evident even when switching to nonintegrated detectors on a precession tool, as experimental set-up becomes challenging and time-consuming. Here, we introduce multi-angle precession electron diffraction (MAPED): a method to perform electron diffraction by collecting sequential 4D-STEM scans at different incident beam tilts. The multiple diffraction datasets are averaged together postacquisition, resulting in a single dataset that minimizes the impact of the curvature and orientation of the Ewald sphere relative to the crystal under study. Our results demonstrate that even four additional tilts improved measurement of material properties, namely strain and orientation, as compared to single-tilt 4D-STEM experiments. We show the versatility and flexibility of our MAPED approach with data collected on a number of microscopes with different hardware configurations and a variety of detectors.

Rheumatoid arthritis is an autoimmune disease that primarily affects synovial joints, mainly in women. This study analyzed the effects of curcumin supplementation combined with prednisone on functionality, lipoperoxidation, inflammatory, and histological characteristics of the tibiofemoral joint and periarticular structures. For this, thirty 18-month-old female Wistar rats were distributed into six groups: control, arthritis, arthritis + curcumin, arthritis + prednisone low-dose, arthritis + prednisone high-dose, and arthritis + prednisone low-dose supplemented with curcumin. Rheumatoid arthritis was experimentally induced via complete Freund's adjuvant injection into the tibiofemoral joint. Treatments were administered by gavage for 14 days: prednisone (2 or 10 mg/kg/day) and curcumin (100 mg/kg/day). Functional, inflammatory, lipoperoxidation, and histological parameters were assessed in the hind paw, blood plasma, and tibiofemoral joint. Generalized mixed and linear models were used for statistical analysis (p = 0.05). Compared to arthritis, low-dose prednisone + curcumin showed significant improvement in lipoperoxidation (p < 0.0001) and leukocyte migration (p = 0.004) and, together with the curcumin group, also showed the most promising results in the semiquantitative assessments of the joint and periarticular structures (p < 0.0001). Thus, treatment with curcumin, alone or combined with low-dose prednisone, restored joint functionality and improved inflammatory, oxidative, and morphological aspects in old female rats with experimentally induced rheumatoid arthritis.

Podocytes are highly interdigitated epithelial cells in the glomerulus that maintain the kidney's filtration barrier, and their injury underlies the progression of diabetic kidney disease. Early podocyte damage is challenging to detect using light or transmission electron microscopy; new techniques like super-resolution microscopy remain limited in capturing the three-dimensional topography of podocytes. Scanning electron microscopy (SEM) offers superior spatial resolution and surface detail; however, standardized quantitative methods to analyze podocyte ultrastructure are lacking. In this study, we developed and compared three analytical approaches to quantify podocyte injury from SEM images in a streptozotocin-induced diabetic mouse model. Using ImageJ software, we measured the slit diaphragm (SD) fraction via (1) thresholding, (2) ridge detection, and (3) foot process plot profiling, comparing diabetic and nondiabetic podocytes. The ridge detection method showed the best diagnostic accuracy (88% sensitivity and 93% specificity), successfully distinguishing diabetic from healthy podocytes. Furthermore, SD fraction measurements correlated negatively with biomarkers of podocyte dysfunction and diabetic stress. This work establishes the first reliable, quantitative pipeline for detecting subtle early podocyte injury in diabetic kidney disease using SEM, providing a valuable tool for future mechanistic and therapeutic studies.

Cutaneous amoebiasis is a severe opportunistic infection, particularly prevalent among immunocompromised individuals, with high mortality due to the insidiousness of the disease, its ability to evade early diagnosis, and lack of specific symptoms. Herein, we aimed to evaluate the therapeutic potential of the marine alga, Padina pavonica, extract as a topical treatment for Acanthamoeba polyphaga skin infections. Immunocompromised mice with induced cutaneous lesions were topical infected with A. polyphaga and examined 3, 9, and 15 days post infection through histological and molecular analysis. Gas chromatography mass spectrometry of the P. pavonica extract exhibited 20 bioactive compounds belongs to steroids, fatty acids, carotenoid, and flavonoids. Infected animals exhibited ulceronecrotic, cellulitis, and intramuscular abscess involving the hind limbs. Moreover, dense inflammatory infiltrates, necrosis, and infiltration of Acanthamoeba trophozoites in dermal areas, sebaceous glands, around blood vessels, mixed with inflammatory cell infiltrate, and muscles were observed. Treatment with P. pavonica significantly accelerate wound healing, reduce inflammation, and restores normal skin architecture. Notably, P. pavonica extract enhances collagen deposition and modulated the expression of TLR2, TLR4, and cytokeratin 18 as key biomarkers of skin injury. These findings highlight, for the first time, the promising role of P. pavonica in managing wound healing and cutaneous acanthamoebiasis.

Since their discovery, scanning probe microscopy (SPM) and scanning electron microscopy (SEM) techniques have been extensively employed across diverse research fields for nanoscale characterization and analysis. While their ex-situ combination has been widely used, the in-situ integration of the two techniques has gained significant traction in recent years. This review highlights the journey of bringing the complementary capabilities of these two instruments into a single platform, with the focus on extracting correlative, multiparametric, and multidimensional information from samples. We discuss key technological advancements, including mechanical integration, readout electronics, imaging modes, and speed optimization, toward the realization of a consistent SPM/SEM hybrid system. Finally, we highlight how such an integrated approach addresses the growing demand for richer nanoscale insights across disciplines ranging from chemical physics to biochemistry.

The torsional vibration of atomic force microscope (AFM) cantilevers is key to high-resolution and high-sensitivity measurements. However, standard models often fail to accurately describe the dynamics of width-varying geometries. In this study, we present an exact analytical model for computing torsional resonance frequencies and mode shapes of overhang- and T-shaped microcantilevers. Our predictions match experimental torsional-to-flexural frequency ratios within 5%, resolving long-standing discrepancies. We uncover the emergence of multiple spatial maxima in higher-order modes and demonstrate how overhang geometry allows tunable frequency shifts. Crucially, we derive a sensitivity function that quantifies the dependence of modal response on tip-surface coupling stiffness, revealing nontrivial geometry-dependent trends. These results offer clear design principles for enhancing AFM sensitivity via geometric control, providing a robust theoretical basis for optimizing next-generation microcantilever probes.