Microscopy Research and Technique最新文献

In this study, we developed nisin-loaded polycaprolactone/sericin nanofibers using electrospinning. The structural properties of the nanofibrous scaffolds were characterized using scanning electron microscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis, and X-ray diffraction analysis. Furthermore, in vitro evaluations assessed swelling ability, biocompatibility, biodegradability, cytotoxicity, and controlled release of nisin. The nanofiber with the optimal combination of properties, including the smallest average fiber diameter and a uniform and bead-free morphology, was selected for nisin loading. The anticancer potency of the nisin-loaded nanofiber against melanoma cells was evaluated using molecular and biochemical assays. Biochemical analyses examined oxidative stress and inflammatory markers (TNF-α, IL-1α, and IL-6) in the cell lysates. In molecular analyses, gene expression levels of p53, caspase-3, TRAIL-1, TRAIL-2, NF-κB, Bcl-2, Bax, Bcl-xL, and Cyclin D1 were measured to elucidate apoptotic and proliferative mechanisms in melanoma cells. Peaks at 3000–650 cm⁻¹ in the nanofibers' FTIR spectrum were characteristic. Thermal gravimetric analysis revealed a two-stage decomposition process for the nanofibers. XRD results showed peaks at 21.74°, 22.39°, and 24.04° for the nanofiber and at 21.59°, 22.17°, 23.94°, 34.80°, and 30.09° for the nisin-loaded nanofiber. In vitro swelling tests demonstrated that the nisin-loaded nanofiber absorbed more water than the unloaded nanofiber. Moreover, the nisin-loaded nanofiber degraded faster than the unloaded nanofiber. Nisin release increased over time. IC₅₀ values for nisin, sericin, and polycaprolactone were 29.58, 75.15, and 11.85 mg/mL, respectively. The expression levels of p53, caspase-3, TRAIL-1, TRAIL-2, NF-κB, Bcl-2, Bax, Bcl-xL, and Cyclin D1 genes in G361 cells were evaluated in comparison to the control group. It was observed that gene expression was stimulated in all regions treated with nisin-loaded PCL/sericin nanofibers, except for the p53 gene. Molecular and biochemical analyses revealed that the nisin-loaded nanofiber induced apoptosis, reduced inflammation and oxidative stress levels, and enhanced antioxidant activity. These findings suggest the anticancer potential of the nisin-loaded nanofiber.

Sambucus ebulus is mainly distributed in the northern, northwestern, and northeastern regions of Iran and is characterized by its perennial growth habit and the characteristics of long, creeping, and branched rhizomes. In the present study, the genetic diversity of seven populations of S. ebulus based on molecular ISSR data and as well as the micromorphology of seeds and leaves in nine populations of this species in Iran was investigated. The AMOVA (analysis of molecular variance) test showed that 87% of the total genetic variance was due to genetic differences among populations, while 13% was due to genetic variability within populations, indicating a high degree of genetic variation among S. ebulus populations. The discriminatory power of ISSR (Inter Simple Sequence Repeat) loci, determined by analyzing Gst against Nm (the number of migrants), showed that almost all ISSR loci have excellent discriminatory power. Thus, ISSR markers are effective in differentiating the studied S. ebulus populations. The Mantel test showed a significant correlation between genetic and geographic distance. In addition, it demonstrated the isolation mechanism responsible for the population structure in the S. ebulus plant populations. The micromorphological study revealed that the stomata are anomocytic and the epidermal cells of the different S. ebulus populations have irregular cell shapes with anticlinal walls ranging from straight to curved. The seed shape was described as predominantly almond-shaped, and the surface of the seed coat of the studied taxa showed a reticulate pattern. Our findings not only demonstrate a considerable degree of genetic diversity among populations of S. ebulus , but also emphasize the importance of micromorphological traits for understanding this species. This study provides a foundation for future research on the ecological importance and conservation of S. ebulus in Iran.

Colorectal cancer (CRC) is one of the leading gastrointestinal malignancies, underscoring the need for an in-depth analysis of the cellular within the tumor microenvironment. While pathological imaging remains the gold standard for cancer diagnosis, it requires extensive annotation time and expert knowledge. Therefore, we propose hierarchical attention multi-instance learning (HAMIL) for label-free CRC typing. Specifically, we integrate optical time-stretch (OTS) imaging technology with microfluidic cell focusing to develop a high-throughput cell image acquisition system, enabling efficient collection of CRC cell images. We measure 10 clinical samples, including 5 from normal samples and 5 from cancerous samples, resulting in a total of 363,931 cell images to construct a high-throughput CRC typing dataset. Based on the clinical CRC typing dataset, our proposed HAMIL utilizes an instance attention layer to extract instance attention weights from individual single-cell instances, allowing for fine-grained modeling of tumor heterogeneity and the tumor microenvironment. Building upon these instance attention weights, the bag attention layer integrates bag-level feature representations, capturing the overall characteristics of the high-throughput cellular population on a global scale. The experimental results show that HAMIL exceeds eight advanced MIL methods and reaches an 86.30% F1 score, which is expected to provide an effective new pathway for clinical CRC typing.

Titanium dioxide (TiO₂) thin films were deposited on glass substrates under HV conditions at room temperature by the physical vapor deposition method. Produced titanium thin films were post-annealed at 573 K at different oxygen flows (0, 9 and 23 cm³/s). The influence of different oxygen flows on nano-structure, crystallography, and optical parameters of TiO₂ films was investigated by XRD, AFM, and spectrophotometer in the UV–VIS wavelength range. Other optical parameters were calculated using the Kramers-Kronig computational method on reflectivity curves. The XRD pattern displays the anatase phase for TiO₂ thin films. With increasing oxygen flow, it became highly transparent in the visible range. It was found that the optical absorption decreased from the UV to near IR region. Various optical parameters such as n, k, σ₁ and σ₂ have been discussed.

Camels have unique morphological traits that enable them to adapt well to harsh conditions. This work aims to describe the vascular architecture of the camel retina and investigate its cellular components with a focus on the distribution of mitochondria in Muller cells and photoreceptors, using light and electron microscopy. The camel retina is euangiotic in which blood vessels extend in the inner retina from the nerve fiber layer to the outer plexiform layer. The pericytes are embedded in the basement membrane of the retinal capillaries, and overlapping of pericytes could be observed. Glial cells are localized in the vicinity of blood vessels. Muller cells display mitochondria throughout their length, from their end-feet, which form the inner limiting membrane, to their scleral end, which forms the outer limiting membrane. Interestingly, the bodies of camel Muller cells are densely packed with mitochondria, while their end-feet show few mitochondria. Numerous mitochondria could be observed in the axons and synaptic terminals of rods and cones. Photoreceptor bodies are devoid of mitochondria. The inner segment's ellipsoid region is densely packed with mitochondria, whereas the outer segment lacks them. In conclusion, these findings provide new insights into the vascular and cellular organization of the camel retina, highlighting key adaptations such as a well-developed inner retinal vasculature, specialized features of the inner blood–retinal barrier, and a distinctive pattern of mitochondrial distribution in Muller cells and photoreceptors. This structural specialization may play a crucial role in maintaining retinal function under the challenging environmental conditions camels face.

This study was carried out using light and scanning electron microscopy to examine in detail the anatomical and micromorphological characteristics of roots, stems, and leaves of six Centaurea taxa (two of which are endemic) to determine the characters that are important for the taxa studied. For anatomical investigations, transverse and superficial sections were taken from root, stem, and leaf organs and examined by light microscopy. For micromorphological assessments, dried leaf surfaces were analyzed via scanning electron microscopy (SEM). Several statistical methods were used for data analysis. A total of 38 characters were considered to determine the anatomical differences among the taxa. Anatomical analyses indicated that variations in the structure of sclerenchyma, phloem, and cortex parenchyma in root; epidermis, chlorenchyma, sclerenchyma, and phloem in stem; and upper epidermis, upper, and lower stomatal characteristics in leaf, including stomatal and epidermal cell density, were statistically significant among the taxa. SEM investigations revealed the presence of four types of trichomes and extrafloral nectaries (only C. carduiformis DC. subsp. carduiformis var. carduiformis) on the leaf surfaces.

Identification of chromosome pairs is important for karyotype generation and genetic disease prediction. Conventional methods tend to fail with structural variations of the chromosomes and imprecise boundaries. To solve these issues, we propose a deep learning architecture, Edge Fusion Attention Network (EFANet), for chromosome classification. It is a new architecture that combines the Adaptive Edge Preserve Fusion (AEPF) algorithm with the Feature Focused Attention Network (F²ANet). The AEPF algorithm clearly identifies chromosome boundaries and highlights the morphological differences. It improves feature representation by combining edge features with intensity, thereby ensuring accurate classification. The F²ANet block in EFANet improves classification using three main components: a feature extraction block, an attention block with both channel and spatial attention, and a classification block. Our proposed method ensures accurate chromosome classification, which is essential for diagnosing genetic disorders such as aneuploidies and translocations. Edge detection, a key feature of EFANet, enhances the identification of chromosome abnormalities by focusing more on unusual shapes than normal ones. Our proposed EFANet showed strong performance with 99.5% accuracy, 99.48% F1 score, 99.63% precision, and 99.45% recall. These results highlight its effectiveness in edge detection, which is important for improving automated chromosome analysis. This approach tremendously improves karyotyping by overcoming the limitations of the traditional approaches, resulting in more accurate and timely genetic disease diagnosis and eventually better patient outcomes.

Primula denticulata (Primulaceae) has long been used in traditional medicine to treat a variety of diseases. Around the globe, it is used to cure different diseases such as bronchitis, enhanced bronchial output, making phlegm less thick, asthma, joint discomfort, fever, diarrhea, sleeplessness, urinary infections, wound healing, eye illnesses, and dysuria. The study's findings provide several pharmacognostic benchmarks that support the maintenance of P. denticulata 's purity, safety, and effectiveness. Light and scanning electron microscopes (SEM and LM) were used to investigate several plant sections, and cross-sectional images yielded several useful botanical features. During the macroscopic evaluation procedure, the form, color, size, odor, and surface characteristics of the plant parts were evaluated. The pharmacognostic standardization parameters (ash values, loss on drying, swelling index, hemolytic index, and foaming index) were determined in accordance with the guidelines provided by the World Health Organization. When the heavy metal content was examined using the atomic absorption spectrophotometer (AAS), it was discovered that both heavy metals and trace elements were found within allowable bounds. Qualitative phytochemical tests were performed on plant extracts to determine their contents, including alkaloids, flavonoids, saponins, glycosides, tannins, carbohydrates, lipids, and protein. Preliminary phytochemical testing indicates the major classes of phytoconstituents that are found in the plant. The quantitative and qualitative microscopic characteristics help to set criteria for planting pharmacopeia. Several pharmacognostic parameters, alike size, shape, and structure of various plant constituents described in connection with physicochemical and phytochemical examination, could be assessed with significant advantage for future research.