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OBJECTIVE: The purpose of this study was to examine the histopathologic, ultrastructural and immunohistochemical changes in the umbilical cord in women diagnosed with HELLP syndrome. MATERIALS AND METHODS: Postpartum umbilical cords of 40 patients at the 35-38th week of pregnancy were included. 20 severe preeclamptic (HELLP) and 20 normal umbilical cords were used. After the follow-up of tissue parts of 10% formaldehyde solution for histopathology and immunohistochemistry, histopathological and angiopoietin-1 and vimentin antibodies were examined as immunohistochemical after routine paraffin follow-up. For electron microscope analysis, umbilical cord samples were taken into 2.5% glutaral aldehyde solution. RESULTS: In the statistical comparison, mean difference in increased diameter and additional anomaly on the ultrasound of preeclamptic patients was statistically different compared to control patients. In the HELLP group, hyperplasia and degenerative changes, pyknosis of the endothelial cell nuclei of the vessels and apoptotic changes in some regions were observed. Immunohistochemical analysis showed that endothelial cells, basal membrane and fibroblast cells in the HELLP group expressed high levels of vimentin. Angiotensin-1 expression was increased in amniotic epithelial cells, endothelial cells and some pericyte cells. CONCLUSIONS: As a result, it was observed that the signaling that started with trophoblastic invasion with the effect of hypoxia in severe preeclampsia and continued with dysfunction in endothelial cells was parallel to the increase in angiotensin and vimentin receptors. It is thought that the ultrastructural change in endothelial cells may cause disruption of the collagenized structure in Wharton gel, which supports this, and may cause adverse effects in fetal development and nutrition. [ABSTRACT FROM AUTHOR]

Thin endometrium, defined as an endometrial thickness of less than 7 mm during the late follicular phase, is a common cause of frequent cancelation of embryo transfers or recurrent implantation failure during assisted reproductive treatment. Small proteoglycans regulate intracellular signaling cascades by bridging other matrix molecules and tissue elements, affecting cell proliferation, adhesion, migration, and cytokine concentration. The aim of the study is to investigate the role of small leucine-rich proteoglycans in the pathogenesis of thin and thick human endometrium and their differences from normal endometrium in terms of fine structure properties. Normal, thin, and thick endometrial samples were collected, and small leucine-rich proteoglycans (SLRPs), decorin, lumican, biglycan, and fibromodulin immunoreactivities were comparatively analyzed immunohistochemically. The data were compared statistically. Moreover, ultrastructural differences among the groups were evaluated by transmission electron microscopy. The immunoreactivities of decorin, lumican, and biglycan were higher in the thin endometrial glandular epithelium and stroma compared to the normal and thick endometrium ( p  < .001). Fibromodulin immunoreactivity was also higher in the thin endometrial glandular epithelium than in the normal and thick endometrium ( p  < .001). However, there was no statistical difference in the stroma among the groups. Ultrastructural features were not profoundly different among cases. Telocytes, however, were not seen in the thin endometrium in contrast to normal and thin endometrial tissues. These findings suggest a possible role of changes in proteoglycan levels in the pathogenesis of thin endometrium.

Purpose: To examine corneal buttons with light and transmission electron microscopy (TEM) to visualize the interface area and highlight the ultrastructural corneal changes after deep anterior lamellar keratoplasty (DALK)., Methods: Two patients underwent excimer laser-assisted penetrating repeat keratoplasty after predescemetic DALK. The corneal buttons were examined by light microscopy and TEM., Results: The light microscopic examination of the corneal buttons revealed fragments of a second Descemet's membrane in the central and midperipheral areas (Case 1). In both cases, visualization of the interface area was not possible by light microscopy. The donor and host stroma were tightly attached without dehiscence. TEM identified the interface area by irregularities in the collagen distribution between the donor and host stroma. The thickness of the remaining recipient corneal stroma measured approximately 30 µm (Case 1) and 100 µm (Case 2), respectively. In the host stroma, TEM revealed the absence or degeneration of keratocytes, accumulation of amorphous material between the collagen lamellae, and vacuolar inclusions dispersed in the stroma, forming a band-like zone anterior to Descemet's membrane., Conclusion: The interface area after DALK has been mainly investigated by in vivo confocal microscopy. Light microscopy and TEM findings indicate remodeling processes after DALK that are associated with increased keratocyte degeneration and structural alterations of the extracellular matrix in the host stroma. The choice of surgical method may influence the postoperative morphological and functional outcome since these findings were primarily apparent in the remaining host stroma. Therefore, complete exposure of Descemet's membrane is an important prognostic factor for the postoperative visual outcome., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)

Sandwich freezing is a method of rapid freezing by sandwiching specimens between two metal disks and has been used for observing exquisite the close-to-native ultrastructure of living yeast and bacteria. Recently, this method has been found to be useful for preserving cell images of glutaraldehyde-fixed animal and human tissues. In the present study, this method was applied to observe the fine structure of mouse glomerular capillary loops. Morphometry was then performed, and the results were compared with the data obtained by an in vivo cryotechnique, which may provide the closest ultrastructure to the native state of living tissue. The results show that the ultrastructure of glomerular capillary loops obtained by sandwich freezing-freeze-substitution after glutaraldehyde fixation was close to that of the ultrastructure obtained by in vivo cryotechnique not only in the quality of cell image but also in quantitative morphometry. They indicate that the ultrastructure obtained by sandwich freezing-freeze-substitution after glutaraldehyde fixation may more closely reflect the living state of cells and tissues than conventional chemical fixation and dehydration at room temperature and conventional rapid freezing-freeze-substitution of excised tissues without glutaraldehyde fixation. Sandwich freezing-freeze-substitution techniques should be used routinely as a standard method for observing the close-to-native ultrastructure of biological specimens., (© The Author(s) 2022. Published by Oxford University Press on behalf of The Japanese Society of Microscopy. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

The paper presents a summary of examinations on the variation of pycnidia and conidia of the following Opegrapha species occurring in Poland: O. atra, O. calcarea, O. dolomitica, O. gyrocarpa, O. niveoatra, O. rupestris, O. varia, O. vermicellifera, O. viridis and O. vulgata.

In this study, following the fibronectin-coated integrin activation in ovarian cancer cells (SKOV-3), endoplasmic reticulum (ER) stress was generated by intracellular calcium increase and then possible apoptotic effects were investigated. Tunicamycin (TN) concentrations and intracellular calcium alterations in SKOV-3 cells were analyzed by flow cytometry using Fluo-3 AM ve Rhod-2 AM flourescent dyes. Apoptotic cell death dependent to ER stress that generated after the treatment with 18 pM TN were investigated by Annexin V / PI protocol and the localisations of cytochrome c and EndoG proteins were also imaged by fluorescent microscope. In addition, morphological alterations were determined by Transmission electron microscope. Following the treatment with 18 pM TN of SKOV-3 cells staining with Fluo-3 AM ve Rhod-2 AM, cytoplasmic and mitochondrial Ca+2 increases were observed, respectively. Correspondingly, early apoptosis percentage was 11.38 % and late apoptosis percentage was 10.24% in SKOV-3 cells. After 2 h, TN incubations of mitochodrial apoptotic proteins cytocrome c and EndoG, flourescent radiations were found as more intense than non-coating cells. Apoptotic changes depending on ER stress in fibronectin coated SKOV-3 cells were determined as plasma and nucleus membrane damages, nucleus condensation and intense heterochromatin structures in nucleus by fragmentation. On the other hand, autophagic findings were also obseved. As a result, calcium dependent apoptotic process in SKOV-3 cells in metastatic stage were partially shown. Electron microscopic findings showed that TN treatment effectively induced ER stress-associated apoptosis and autophagy in SKOV-3 cells that effect becomes stronger with binding of cells to fibronectin. However, the detailed mechanism underlying the crosstalk between TN-induced autophagy and apoptosis in SKOV-3 cells warrants further study. [ABSTRACT FROM AUTHOR]

This study was done by examining the biopsy materials in the Histology-Embryology Department under light and electron microscopy, that were taken from a total of 27 patients, 19 females and 8 males with an age range of 10 to 61 years, who were operated because of chronic otitis media in University of Istanbul Cerrahpafla Medical Faculty Otolaryngology Department. Besides common findings like cholesteatoma and metaplasia observed in majority of the cases, various specific histopathologic structural changes like development of abnormal cilia, intracellular canals and presence of neoplastic areas were also recorded.

Projections from auditory cortex (AC) can alter the responses of cells in the inferior colliculus (IC) to sounds. Most IC cells show excitation and inhibition after stimulation of the AC. AC axons release glutamate and excite their targets, so inhibition is presumed to result from cortical activation of GABAergic IC cells that inhibit other IC cells via local projections. However, it is not known whether cortical axons contact GABAergic IC cells directly. We labeled corticocollicular axons by injecting fluorescent dextrans into the AC in guinea pigs. We visualized the tracer with diaminobenzidine and processed the tissue for electron microscopy. We identified presumptive GABAergic profiles with post-embedding anti-GABA immunogold histochemistry on ultrathin sections. We identified dextran-labeled cortical boutons in the IC and identified their postsynaptic targets according to morphology (e.g., spine, dendrite) and GABA-reactivity. Cortical synapses were observed in all IC subdivisions, but were comparatively rare in the central nucleus. Cortical boutons contain round vesicles and few mitochondria. They form asymmetric synapses with spines (most frequently), dendritic shafts and, least often, with cell bodies. Excitatory boutons in the IC can be classified as large, medium or small; most cortical boutons belong to the small excitatory class, while a minority (~14%) belong to the medium excitatory class. Approximately 4% of the cortical targets were GABA-positive; these included dendritic shafts, spines, and cell bodies.We conclude that the majority of cortical boutons contact non-GABAergic (i.e., excitatory) IC cells and a small proportion (4%) contact GABAergic cells. Given that most IC cells show inhibition (as well as excitation) after cortical stimulation, it is likely that the majority of cortically-driven inhibition in the IC results from cortical activation of a relatively small number of IC GABAergic cells that have extensive local axons.