Microscopy Research and Technique最新文献

Medical Image plays a vital role in diagnosis, but noise in patient scans severely affects the accuracy and quality of images. Denoising methods are important to increase the clarity of these images, particularly in low-resource settings where current diagnostic roles are inaccessible. Pneumonia is a widespread disease that presents significant diagnostic challenges due to the high similarity between its various types and the lack of medical images for emerging variants. This study introduces a novel Diffusion with swin transformer-based Optimized Crow Search algorithm to increase the image's quality and reliability. This technique utilizes four datasets such as brain tumor MRI dataset, chest X-ray image, chest CT-scan image, and BUSI. The preprocessing steps involve conversion to grayscale, resizing, and normalization to improve image quality in medical image (MI) datasets. Gaussian noise is introduced to further enhance image quality. The method incorporates a diffusion process, swin transformer networks, and optimized crow search algorithm to improve the denoising of medical images. The diffusion process reduces noise by iteratively refining images while swin transformer captures complex image features that help differentiate between noise and essential diagnostic information. The crow search optimization algorithm fine-tunes the hyperparameters, which minimizes the fitness function for optimal denoising performance. The method is tested across four datasets, indicating its optimal effectiveness against other techniques. The proposed method achieves a peak signal-to-noise ratio of 38.47 dB, a structural similarity index measure of 98.14%, a mean squared error of 0.55, and a feature similarity index measure of 0.980, which outperforms existing techniques. These outcomes reflect that the proposed approach effectively enhances the quality of images, resulting in precise and dependable diagnoses.

Electrospun nanofibers offer sufficiently large pore size, good porosity, and interconnectivity for the integration of cells into the scaffold. Consequently, there has been a lot of interest in tissue engineering with electrospun nanomaterials. Numerous cellular functions can be supported by biocompatible conducting polymers. In this study, polyacrylonitrile (PAN)/polypyrrole (PPy) nanofibrous films were prepared by the electrospinning technique and examined as a scaffold for IHOEC ovarian cell attachment and proliferation. The rationale for embedding ovarian cells in a scaffold is particularly relevant to fields such as ovarian tissue engineering, infertility treatments, and postcancer tissue repair. This approach aims to enable cells to grow and form functional tissue in an environment similar to their natural microenvironment. Straight, smooth, and beadless PAN/PPy nanofibers with an average diameter of 216 ± 35 nm were obtained and analyzed by AFM, SEM, TEM, TGA, XRD, and WCA characterization methods. WCA measurements revealed that the nanofibers exhibited hydrophilic behavior, with WCA values of 14.93° ± 0.37 and 12.51° ± 0.50 being measured for the PAN and PAN/PPy nanofibers, respectively. PAN/PPy nanofibrous scaffolds were examined as a tissue engineering scaffold material for IHOEC ovarian cells, and the morphological properties and viability of cells grown on PAN/PPy nanofibers were observed. Results from the MTT test and SEM pictures demonstrated that IHOEC cells could adhere and proliferate on nanofibers. Consequently, PAN/PPy nanofibrous mats would be a potential candidate for an ovarian tissue scaffold.

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.