Microscopy Research and Technique最新文献

In this study, the secondary male genitalia of Platycnemis dealbata Selys in Selys & Hagen, 1850 was examined for the first time using Scanning Electron Microscope (SEM). The research revealed the ultrastructural features and various sensory structures of these organs. Two main types of sensilla were identified in the secondary genital organ: putative chemical sensilla and hair sensilla that detect mechanical stimuli. The study examined structures such as the ligula head, anterior and posterior hamuli, lamina anterior, and lamina batilliformes in detail. Four projections were observed on the ligula head, and it has been suggested that these projections play a role in sperm transport. Additionally, the hair sensilla on the sternum assist in detecting contact with the female and in anchoring during mating. This research compared the genital structure of P. dealbata with other Platycnemis species and revealed some similarities and differences. The study contributes to our knowledge of the reproductive biology and evolutionary adaptations of the Odonata taxon by presenting new hypotheses about the functions of these complex structures.

The esophagus and stomach of nine adult healthy hooded crows (Corvus cornix) were collected for light and scanning electron microscopes (SEM) as well as histomorphometric analysis. SEM showed that the esophageal mucosa has round-shaped gland openings, extending to its junction with the proventriculus. The proventriculus luminal surface had roughly circular gland openings surrounded by simple mucosal folds that appeared as raised tubular structures. A cuticle at the proventricular–gizzard junction was present. The gizzard cuticle appeared as thread-like rods, while the tubular gastric glands resembled broccoli sprouts. Histologically, the esophageal mucosa exhibited argyrophilic endocrine cells within both the lining epithelium and glandular epithelium. Numerous telocytes surrounded the secretory acini of the superficial and deep proventricular glands and encircled blood vessels in the lamina propria. Columnar to cuboidal (oxynticopeptic) cells were abundant in the deep proventricular glands. The most superficial epithelial cells of the gizzard contained excessive metachromatic granules. Telocytes were detected around the glandular secretory acini within the lamina propria and muscle fibers of the gizzard. The results of the current study suggest that the esophageo-gastric tube histomorphology in hooded crows revealed some characteristics that might be attributed to adaptation to a diverse urban and rural diet.

Globally, breast cancer represents the leading cancer type, with millions of women impacted annually. The success of breast cancer treatment relies heavily on timely detection and precise tumor classification. The classification of breast cancer has gained considerable importance in Deep Learning (DL) and medical research with the development of medical imaging techniques, like histopathological imaging. Many existing DL schemes suffer from overfitting and endure difficulties in effectively mining the key features from high-resolution images with subtle variations. Hence, the Xception Convolutional Deep Maxout Network (Xcov-DMN) is developed to classify breast cancer. At the initial stage, the Mean-Shift Filter is applied to the input histopathological image. Following this, the White Blood Cell Network (WBC-Net) is employed for blood cell segmentation with the Balanced Cross-Entropy (BCE) and Focal Loss for ensuring precise segmentation. Next, Colored Histograms, shape features, Haralick Texture Features, and Complete Local Binary Pattern (CLBP) features are excerpted. Consequently, the developed Xcov-DMN is utilized to classify breast cancer. Xcov-DMN is the combination of the Deep Maxout Network (DMN), Fractional Calculus (FC), and Xception Convolutional Neural Network (XCovNet). Moreover, with learning data at 90%, the Xcov-DMN achieved the highest accuracy of 92.755%, True Negative Rate (TNR) of 91.977%, and True Positive Rate (TPR) of 94.765%.

Sperm cryopreservation is a critical technique for improving the efficacy of artificial insemination in sheep breeding programs. This study evaluated the effects of different extenders and packaging methods on post-thaw ram sperm quality, ultrastructure, and potential reproductive performance. Semen was collected from five healthy Ossimi rams and extended using three cryopreservation media: Tris-egg yolk (Tris-EY), Tris supplemented with 1% soybean lecithin (Tris-SBL), or Tris supplemented with 2 mM butylated hydroxytoluene (Tris-BHT). The extended semen was then packaged in either plastic straws or pellets and cryopreserved in liquid nitrogen. Post-thaw sperm quality was assessed by evaluating progressive motility, viability, and membrane integrity. Sperm ultrastructure was examined using transmission electron microscopy (TEM) and reproductive index. A two-way ANOVA analysis was used to study the effects of the extender and the method of packing. Cryopreservation using straws significantly improved post-thaw sperm quality compared to pellets, demonstrating higher progressive motility (p = 0.003), viability (p < 0.0001), and membrane integrity (p < 0.0001). However, neither the packaging method nor the extender type significantly affected the plasma membrane status, acrosome integrity, or mitochondrial, tail, and nuclear damage (p > 0.05). Ultrastructural analysis confirmed that straws, regardless of the extender used (Tris-EY, Tris-SBL, or Tris-BHT), effectively preserved sperm ultrastructure, including the nucleus, head, acrosome, plasma membrane, and mitochondria. The methods of packaged and extender types did not significantly affect the conception rate and litter size in sheep (p > 0.05). However, it is worth noting that Tris-SBL in straws had the highest conception rate (85.7%) and litter size (1.5 per ewe), while Tris-BHT in pellets had the lowest values (71.4% and 1.2, respectively). This study confirmed that plastic straw packaging significantly improved post-thaw sperm quality. While Tris-EY showed higher reproductive performance, further research is needed to establish statistical significance in pregnancy rates and litter size.

The current study explores the biosynthesis of silver nanoparticles (AgNPs) using green tea (GT) extract (Camellia sinensis) and its application in detecting mercury ions in potable water samples. The biologically synthesized GT-AgNPs were characterized through a series of spectral analyses. The UV–visible spectroscopy of the GT-AgNPs exhibited a λ max at 417 nm. Fourier Transform-Infrared spectroscopy indicated the presence of functional groups (hydroxyl, amines, alkynes, esters, ethers, and thiols) involved in the capping and stabilization of AgNPs. X-ray Diffraction analysis validated the crystalline structure. Electron microscopic studies revealed that synthesized GT-AgNPs are spherical-shaped. Dynamic light scattering indicated an average particle size of 86.3 nm. The zeta potential value > −30 mV suggested that GT-AgNPs are more stable. The detection of Hg²⁺ through colorimetric analysis demonstrated that the introduction of GT-AgNPs into varying concentrations of Hg²⁺ ions resulted in a significant color change from brownish yellow to a colorless solution, thereby recording the Limit of Detection to be 0.6 μM and the Limit of Quantification as 1.82 μM. Results of the recovery study using various micromolar (0.25–0.75 μM) concentrations of Hg²⁺ ions spiked with drinking and tap water showed a relative standard deviation of less than 5% and a recovery rate > 91%. Considering the sensitivity and selectivity of GT-AgNPs, this calorimetric assay clearly emphasized its potential in detecting Hg²⁺ ions in contaminated aquatic ecosystems. Furthermore, the green tea extracts used to fabricate AgNPs presented several advantages: simple, low-cost, and one-step, with no harmful organic solvents.

Plastic has been recognized as a major toxicological problem, but the recent detection of microplastics (MPs) in human fluids and tissues has raised global concern. MPs, mainly fibers and fragments, have been found in oceans, rivers, and lakes. Due to their small size (< 5 mm), aquatic organisms can accidentally ingest them and may ultimately reach humans through the food chain. This study assessed the gut response of Danio rerio exposed to different concentrations and shapes—microfibers (M.Fb.) and microfragments (M.Fg.)—polyethylene terephthalate (PET) MPs via feeding. Adult fish (n = 114) were exposed to 30 MPs for 24 h (acute toxicity) and to 1 or 6 MPs per feed per day for 15 and 30 days (chronic toxicity). The acute test revealed longer gut retention time for M.Fb. than M.Fg. Chronic exposure led to the detection of M.Fg. in gut sections. Histopathological analysis showed coalescence of villi, epithelial detachment, epithelial degeneration, muscle layer displacement, dysplasia, hypertrophy, hyperplasia, and necrosis, particularly at 6 MPs per feed. The histopathological alteration index (HAI) indicated greater damage with higher MP exposure, especially from M.Fb. Overall, these results suggest that in addition to concentration, the shape of the MPs also influences their impact on fish gut health, with M.Fb. exhibiting more severe effects of M.Fg.on the gut.