Enlargement Of Intercellular Spaces Research Articles

T2-FLAIR Mismatch: An Imaging Biomarker for Children's MYB/MYBL1-Altered Diffuse Astrocytoma or Angiocentric Glioma.

T2-FLAIR mismatch is a highly specific imaging biomarker of IDH-mutant diffuse astrocytoma in adults. It has however also been described in MYB/MYBL1-altered low grade tumors. Our aim was to assess the diagnostic power of the T2-FLAIR mismatch in IDH-mutant astrocytoma and MYB/MYBL1-altered low-grade tumors in children and correlate this mismatch with histology. We evaluated MR imaging examinations of all pediatric patients, performed at the Princess Máxima Center for Pediatric Oncology and the University Medical Center Utrecht between January 2012 and January 2023, with the histomolecular diagnosis of IDH-mutant astrocytoma, diffuse astrocytoma MYB/MYBL1-altered, or angiocentric glioma, and the presence of T2-FLAIR mismatch was assessed. Histologically, the presence of microcysts in the tumor (a phenomenon suggested to be correlated with T2-FLAIR mismatch in IDH-mutant astrocytomas in adults) was evaluated. Nineteen pediatric patients were diagnosed with either IDH-mutant astrocytoma (n = 8) or MYB/MYBL1-altered tumor (n = 11: diffuse astrocytoma, MYB- or MYBL1-altered n = 8; or angiocentric glioma n = 3). T2-FLAIR mismatch was present in 11 patients, 3 (38%) in the IDH-mutant group and 8 (73%) in the MYB/MYBL1 group. No correlation was found between T2-FLAIR mismatch and the presence of microcysts or an enlarged intercellular space in either IDH-mutant astrocytoma (P = .38 and P = .56, respectively) or MYB/MYBL1-altered tumors (P = .36 and P = .90, respectively). In our pediatric population, T2-FLAIR mismatch was more often found in MYB/MYBL1-altered tumors than in IDH-mutant astrocytomas. In contrast to what has been reported for IDH-mutant astrocytomas in adults, no correlation was found with microcystic changes in the tumor tissue. This finding challenges the hypothesis that such microcystic changes and/or enlarged intercellular spaces in the tissue of these tumors are an important part of explaining the occurrence of the T2-FLAIR mismatch.

The role of water distribution, cell wall polysaccharides, and microstructure on radish (Raphanus sativus L.) textural properties during dry-salting process

Radish (Raphanus sativus L.) undergoes texture changes in their phy-chemical properties during the long-term dry-salting process. In our study, we found that during the 60-day salting period, the hardness and crispness of radish decreased significantly. In further investigation, we observed that the collaborative action of pectin methylesterase (PME) and polygalacturonase (PG) significantly decreased the total pectin, alkali-soluble pectin (ASP), and chelator-soluble pectin (CSP) content, while increasing the water-soluble pectin (WSP) content. Furthermore, the elevated activities of cellulase and hemicellulase directly led to the notable fragmentation of cellulose and hemicellulose. The above reactions jointly induced the depolymerization and degradation of cell wall polysaccharides, resulting in an enlargement of intercellular spaces and shrinkage of the cell wall, which ultimately led to a reduction in the hardness and crispness of the salted radish. This study provided key insights and guidance for better maintaining textural properties during the dry-salting process of radish.

Histological changes in the structural components of the gums in lipopolysaccharide periodontitis

Summary. Inflammatory diseases of periodontal tissues are one of the most important problems in dentistry. There is a strong connection between periodontal pathology and inflammatory diseases of the stomach. The aim of the study – to investigate pathomorphological changes in rat periodontal tissues with generalized lipopolysaccharide periodontitis associated with chronic atrophic gastritis. Мaterials and Methods. The experiments were performed on white outbred male rats weighing 160–180 g. 30 animals were used during the work. The tested animals were divided into the following groups: I – intact rats (control); II – animals with a model of generalized lipopolysaccharide periodontitis. For a morphological study of the periodontium, a fragment of the upper jaw was isolated. Histological preparations were studied using an SEOSCAN light microscope. Such classical research methods make it possible to study the structure of tissues, as well as the nature and depth of morphological changes, the sequence of development of destructive and regenerative processes. Results and Discussion. It has been established that with generalized lipopolysaccharide periodontitis, a reorganization of all structural components of the gum tissue occurs. It is manifested by changes in the epithelium of the mucous membrane of the gums, an increase in the stratum corneum, a decrease in the spinous layer, expansion of intercellular spaces, growth of lymphocytic infiltration, swelling of the connective tissue of the mucous membrane, expansion, blood filling of veins and hemocapillaries, cells of the walls of fibrous structures. Conclusions. Concomitant chronic atrophic gastritis significantly aggravates the pathomorphological picture of periodontitis induced in animals by the endotoxin of gram-negative microflora lipopolysaccharide.

1-MCP prevents ultrastructural changes in the organelles of Dendrobium petals that are induced by exogenous ethylene

Ethylene is a plant hormone that causes flower senescence. Dendrobium flowers are sensitive to ethylene and ethylene can induce premature senescence depending on the cultivar and the ethylene concentration. Dendrobium ‘Lucky Duan’ is one of the most sensitive cultivars to ethylene exposure. Open florets of ‘Lucky Duan’ were subjected to ethylene, 1-MCP, or 1-MCP plus ethylene treatments and compared with an untreated control. Ethylene induced earlier development of color fading, drooping and venation in petals, whereas 1-MCP pre-treatment counteracted these changes. Under light microscopy, epidermal cells and mesophyll parenchyma tissue around the vascular bundles of petals treated with ethylene showed collapsed cells whereas 1-MCP pre-treatment counteracted this collapse. An scanning electron microscopy (SEM) study confirmed clearly that ethylene treatment caused the collapse of mesophyll parenchyma tissue around vascular bundles. Ultrastructural changes were also studied using transmission electron microscopy (TEM) and showed that ethylene treatment induced morphological changes in conjunction with disorganization of the plasma membrane, the nuclei, chromatin, the nucleoli, myelin bodies, multivesicular bodies, and mitochondria including changes in size and number, breakages of membranes, enlargement of intercellular spaces and disintegration. 1-MCP pre-treatment was observed to counter these changes that were induced by ethylene. The role of ethylene-induced ultrastructural changes in the different organelles was apparently associated with membrane damage.

Development of basil ‘Dark Opal’ from explant type and plant regulators

Seedling abnormalities are a common problem in micropropagation and require investigation. This study aimed to assess the growth characteristics and morphoanatomy of stem apices and nodal segments of basil (Ocimum basilicum) ‘Dark Opal’ inoculated in medium containing combinations of 6-benzylaminopurine (BAP) and naphthaleneacetic acid (NAA). Presence of calluses, adventitious roots, and abnormal seedlings was quantified at 20 and 40 days after inoculation. Growth, anatomical, and morphological parameters were evaluated after 80 days. Explant type and regulators influenced the growth and morphoanatomy of basil ‘Dark Opal’. Treatment of stem apices with 0.05 and 0.1 mg L-1 of NAA and BAP increased leaf number, fresh weight, and dry weight and decreased the incidence of calluses and abnormalities. Hyperhydric seedlings showed morphoanatomical alterations, such as disorganization and expansion of intercellular spaces with a consequent increase in parenchymal length. Thus, the results of this research allowed optimizing and understanding the important effects of growth regulators on the development of this species, which will help in in vitro mass culture programs and in biofactories for the production of secondary metabolites.

The M3 Muscarinic Acetylcholine Receptor Promotes Epidermal Differentiation

The M3 muscarinic acetylcholine receptor is predominantly expressed in the basal epidermal layer where it mediates the effects of the autocrine/paracrine cytotransmitter acetylcholine. Patients with the autoimmune blistering disease pemphigus develop autoantibodies to M3 muscarinic acetylcholine receptor and show alterations in keratinocyte adhesion, proliferation, and differentiation, suggesting that M3 muscarinic acetylcholine receptor controls these cellular functions. Chmr3-/- mice display altered epidermal morphology resembling that seen in patients with pemphigus vulgaris. In this study, we characterized the cellular and molecular mechanisms through which M3 muscarinic acetylcholine receptor controls epidermal structure and function. We used single-cell RNA sequencing to evaluate keratinocyte heterogeneity and identify differentially expressed genes in specific subpopulations of epidermal cells in Chmr3-/- neonatal mice. We found that Chmr3-/- mice feature abnormal epidermal morphology characterized by accumulation of nucleated basal cells, shrinkage of basal keratinocytes, and enlargement of intercellular spaces. These morphologic changes were associated with upregulation of cell proliferation genes and downregulation of genes contributing to epidermal differentiation, extracellular matrix formation, intercellular adhesion, and cell arrangement. These findings provide, to our knowledge, previously unreported insights into how acetylcholine controls epidermal differentiation and lay a groundwork for future translational studies evaluating the therapeutic potential of cholinergic drugs in dermatology.

The Combination Analysis Between Bacillus thuringiensis Sip1Ab Protein and Brush Border Membrane Vesicles in Midgut of Colaphellus bowringi Baly.

The secretory insecticidal protein Sip1Ab and crystal protein Cry8Ca from Bacillus thuringiensis (Bt) are widely recognized for their coleopteran insecticidal activities. It is worthwhile to investigate the insecticidal mechanisms of these two proteins against Colaphellus bowringi Baly, which is a serious pest of cruciferous vegetables in China and other Asian countries. To that end, the genes encoding the Sip1Ab and Cry8Ca proteins were amplified from the strain QZL38 genome, then expressed in Escherichia coli, after which bioassays were conducted in C. bowringi larvae. After feeding these two proteins, the histopathological changes in the midguts of C. bowringi larvae were observed using transmission electron microscopy (TEM), and the Brush Border Membrane Vesicle (BBMV) was extracted for competition binding assays. TEM showed that ingestion of Sip1Ab caused a significant reduction in growth of the larvae, disruption of midgut microvilli, and expansion of intercellular spaces. Competition binding assays demonstrated that Sip1Ab bound to C. bowringi BBMV with a high binding affinity. However, a mixture of the two proteins in equal proportions showed no significant difference in insecticidal activity from that of Sip1Ab. These results could provide a molecular basis for the application of Sip1Ab in coleopteran insect control and contribute to the study of the Sip1Ab insecticidal mechanism as well.

Epidermal Hyaluronan in Barrier Alteration-Related Disease.

In skin, although the extracellular matrix (ECM) is highly developed in dermis and hypodermis, discrete intercellular spaces between cells of the living epidermal layers are also filled with ECM components. Herein, we review knowledge about structure, localization and role of epidermal hyaluronan (HA), a key ECM molecule. HA is a non-sulfated glycosaminoglycan non-covalently bound to proteins or lipids. Components of the basal lamina maintain some segregation between the epidermis and the underlying dermis, and all epidermal HA is locally synthesized and degraded. Functions of HA in keratinocyte proliferation and differentiation are still controversial. However, through interactions with partners, such as the TSG-6 protein, HA is involved in the formation, organization and stabilization of the epidermal ECM. In addition, epidermal HA is involved in the formation of an efficient epidermal barrier made of cornified keratinocytes. In atopic dermatitis (AD) with profuse alterations of the epidermal barrier, HA is produced in larger amounts by keratinocytes than in normal skin. Epidermal HA inside AD lesional skin is located in enlarged intercellular spaces, likely as the result of disease-related modifications of HA metabolism.

Harmful effects of fipronil exposure on the behavior and brain of the stingless bee Partamona helleri Friese (Hymenoptera: Meliponini)

Fipronil is a pesticide widely used to control agricultural and household insect pests. However, fipronil is highly toxic to non-target insects, including pollinators. In this study, we investigated the acute effects of fipronil on the behavior, brain morphology, antioxidant activity, and proteins related to signaling pathways on the brain of workers of the stingless bee Partamona helleri. The ingestion of fipronil increases both the walking distance and velocity and causes enlarged intercellular spaces in the Kenyon cells and intense vacuolization in the neuropils of the brain. Moreover, fipronil decreases the activity of catalase (CAT) and increases the activity of glutathione S-transferase (GST). However, there is no difference in superoxide dismutase (SOD) activity between the control and fipronil. Regarding immunofluorescence analysis, bees exposed to fipronil showed an increase in the number of cells positive for cleaved caspase-3 and peroxidase, but a reduction in the number of cells positive for ERK 1/2, JNK and Notch, suggesting neuron death and impaired brain function. Our results demonstrate that fipronil has harmful effects on the behavior and brain of a stingless bee, which may threaten the individuals and colonies of this pollinator.

Double-blind randomized study of lidocaine, bupivacaine, levobupivacaine, and ropivacaine myotoxicity in rats

Background. Myotoxicity of local anesthetics in a clinical practice was revealed at various types of regional anesthesia. The degree of functional recovery of damaged muscles and the length of time before the recovery differ significantly in different studies. Despite the generally accepted opinion about the anti-inflammatory effect of local anesthetics, a number of experimental studies have shown that an inflammatory reaction developed at the place of injection into a muscle tissue.
 Material and methods. A double-blind randomized study was conducted on 800 rats. A control group was formed whose members were introduced with 0.9% sodium chloride solution. Lidocaine concentrations under the study were 0.5%, 1%, 1.5%, 2%; bupivacaine, ropivacaine 0.25%, 0.5%, 0.75%, 1%; ropivacaine 0.25%, 0.5%, 0.75%. A 0.2-mL drug was injected into the biceps muscle under the ultrasound control. The sampling of drugs was as follows: stage 1 was in 1 h after the injection, stage 2 was in 2 days, stage 3 was in 7 days, stage 4 was in 14 days, stage 5 was in 21 days. Signs of an inflammation and damage of a muscle tissue were examined.
 Results. An injection of a saline solution to laboratory animals of the control group caused the expansion of intercellular spaces and connective tissue partitions. There were no signs of cell necrosis or apoptosis. The injection of local anesthetics within an hour caused an inflammatory infiltration and a damage to a muscle tissue. The data of pairwise comparisons showed that at the stages of 1 h and day 2 in all the studied groups, the severity of a damage and an inflammation was greater than in the control group with the introduction of 0.9% sodium chloride solution. Then, there was a decrease in signs of a damage and an inflammation. At the stage of day 21, there were no statistical differences in comparison with group 1 in any of the study groups. The dependence of the appearances of damage or inflammation in a muscle tissue on the concentration of a local anesthetic was determined by an ordinal regression model. The regression model indicators were significant. They allowed us to describe 87% for damage and 95% for inflammatory changes.
 Сonclusion. The toxicity of local anesthetics appeared as a damaging effect and development of an inflammatory infiltration. Local anesthetics were toxic in all studied groups with all concentrations. The higher the concentration of the anesthetic, the more expressed was the damaging effect and the development of signs of the inflammation. The maximum development of the damaging effect was at the stages of hour 1 and day 2 of the study, then there was a decrease in signs of myotoxicity, and by 21 days, the signs of damage and inflammation completely disappeared. The comparative analysis did not reveal any statistical differences that allow us to expressly form a rating from the most to the least myotoxic drug.

Ultrastructure of Granulosa Cells of Bovine Ovarian Antral Follicles in Relation to Atresia

Abstract The aim of this study was to describe the most common forms of ovarian follicle atresia in large antral follicles of cows and quantify the occurrence of different cell structures in each form. Atresia of antral follicles in ovaries was determined on the basis of ultrastructural images acquired by electron microscopy of ultrathin sections contrasted with uranyl acetate and lead citrate to visualize cell organelles. All forms of atresia in large follicles are accompanied by regressive changes of the granulosa cells. The initial form of atresia is characterized by enlarged intercellular spaces after the disruption of the gap junctions and desmosomes. Small collapsed cells with pyknotic nuclei, substantially reduced the cytoplasm and a higher incidence of lysosomes are located on the surface of the granulosa layer. The stratum granulosum wall collapses and the basal membrane is swollen with a rupture of the lamina basalis. Obliterative atresia is characterized by a multiplied loose connective tissue consisting of collagen fibers, fibroblasts, histiocytes, blood capillaries and sporadically granulocytes. The cystic form of atresia is characterized by small collapsed, pyknotic granulosa cells settled in one or two layers. In luteinization-associated atresia, granulosa cells are hypertrophied, their cytoplasm contains smooth endoplasmic reticulum and mitochondria with tubules. In conclusion, the initial atresia of large antral ovarian follicles is associated with processes of cell death, followed by multiplication of the loose connective tissue cells, its dystrophy and hyalinization of the collagen fibers. Ultrastructural examination could be used as a complementary method to improve histopathological diagnostics of cow reproductive organs in veterinary practice.

SUBMICROSCOPIC CHANGES OF STRUCTURAL COMPONENTS OF THE SPLEEN DUE TO THE ACTION OF MONOSODIUM GLUTAMATE

The results of an experimental study conducted on white male rats and females of reproductive age were analyzed in order to detect submicroscopic changes in the structural components of the spleen under the action of monosodium glutamate in the dynamics. For two, four, six and eight weeks, the animals received monosodium glutamate at a dose of 0.07 g / kg body weight daily with food. Sections of the spleen were made on a UMTP-6M ultramicrotome with a diamond knife (DIATOM) and double contrast was performed according to Reynolds and uranyl acetate. Submicroscopic examinations of the organ were performed using an electron transmission microscope TEM-100. The investigated material was photodocuted using a SONY – H9 digital camera. The first violations of the structural components of the spleen are observed after two weeks, namely the expansion of intercellular spaces in both white and red pulp of the spleen, which contain vacuole-like structures, an increase in plasma cells, the cytoplasm of which is filled with dilated tubules. In dynamics with increase in duration of reception changes deepen, reaching a maximum in 8 weeks of experiment. Electron microscopy revealed that the signs of adaptive-compensatory processes by the end of the experiment lead to a loss of regenerative function.

Microcystin-LR promotes zebrafish (Danio rerio) oocyte (in vivo) maturation by activating ERK1/2-MPF signaling pathways, and cAMP is involved in this process

Cyanobacterial blooms and their secondary metabolites, microcystins (MCs), are not only toxic to aquatic organisms, but also to humans. MCs exert reproductive toxicity in female fish by affecting the oocyte development. However, the mechanism behind MC-LR interference in oocyte development remains largely unknown. In our study, adult female zebrafish were exposed to MC-LR (0, 1, 5, 20 μg/L) for 30 d. After exposure to MC-LR for 30 d, fertilized eggs from the treated females and healthy males were collected and cultured in water without MC-LR. Histomorphological observations showed pathological damage in the ovary after MC-LR exposure, which was mainly characterized by enlarged intercellular spaces, detachment of follicular cells from oocytes, and vacuolation of parenchymal tissues. The 20 μg/L MC-LR treatment caused a remarkable increase in the rate of the zebrafish oocytes germinal vesicle breakdown (GVBD) and a significant decrease in the levels of cyclic adenosine monophosphate (cAMP) and vitellogenin (VTG). In addition, the phosphorylation levels of the extracellular signal-regulated kinases (ERK) were elevated in ovaries from zebrafish exposed to 5 and 20 μg/L MC-LR, and cyclinB phosphorylation levels were also upregulated notably in the 20 μg/L MC-LR group. However, MC-LR exposure did not cause any change in the levels of cAMP-dependent protein kinase (PKA) protein and cdc2 phosphorylation in all the treatments. All the doses of MC-LR reduced the number of eggs, prematurely hatched the fertilized eggs and increased the abnormal rate of offspring generation. In summary, the present study demonstrates that MC-LR promotes oocyte maturation by activating the ERK1/2 and MPF signaling pathways, and cAMP is involved in this process.

Application of Bio-Impedance Analysis to Estimate the Condition of Yellowtail (Seriola quinqueradiata) Muscle at Different Storage Temperatures.

Changes in impedance at 2 kHz, adenosine triphosphate (ATP) content, and muscle contraction were evaluated in yellowtail during 0 (ice), 5, 10, 15, and 20°C storage. Histological changes during ice storage were also measured. At any temperature, although impedance increased with both rigor mortis and ATP consumption during early storage, it began to decrease rapidly when ATP was almost depleted. Moreover, temporarily increasing impedance had a strong relationship with ATP content; decreasing impedance had a significant correlation with storage temperature after ATP depletion. Furthermore, impedance increased with narrowing of intercellular spaces when sarcolemma was intact and decreased with expansion of intercellular spaces when sarcolemma was leaky. Meanwhile, changes of sarcolemma and intercellular spaces were accompanied by ATP change. Thus, ATP is one significant physiological factor for impedance change, and temperature greatly influenced impedance after depletion of ATP. Results suggest that impedance analysis can be used as a convenient and nondestructive method to diagnose condition of tissue at different storage temperatures. Bioelectromagnetics. 2019;40:488-497. © 2019 Bioelectromagnetics Society.

The possible role of folic acid against sodium fluoride induced toxicity in the skin of adult male albino rats.

Background:Exposure of human being to fluoride occurs through various sources as food, water, toothpastes and fluoride additives. This exposure is either to low concentrations for long periods or to high concentrations and both may lead to poisoning. Folic acid (FA) has an important free radical scavenging property which makes it the most potent antioxidants. Moreover, it suppresses apoptosis and boost cell survival. Aim of the work: To evaluate the protective and therapeutic role of FA against sodium fluoride (NaF) induced toxicity on adult male rat skin. Materials and Methods:Forty adult (3 months) male albino rats(weighing 200-220 gm) were equally divided into 4 groups (10 rats each):group 1 (control),group 2 (NaF, for 4 weeks),group 3 (NaF, for 4 weeks followed by FA for another 4 weeks) and group 4 (NaF plus FA for 4 weeks). Both NaF (25mg/Kg b.w.) and FA (8 mg/Kg b.w.) were given orally daily. The rats were sacrificed and samples of the back skin were processed for histological, immunohistochemical (Bcl2 antiapoptotic protein) and morphometric studies. Results:Group 2 revealed signs of degeneration in epidermal cells, expansion of intercellular spaces and destructed organelles. There wasa reduction in epidermal thickness with disturbance in collagen fibers arrangement and weak immunoreactivity of Bcl-2. FA induced relative improvement in the dermal and epidermal structures in group 3 while there was preservation of these structures in group 4. Conclusion:FA ameliorates NaF induced harmful effects on skin in addition to its valuable preventive role.

Morphofunctional status of inner ear's cells in case of experimental hearing loss

To study ultrastructural changes in stria's vascularis cells of inner ear and determine possible ways of correction. The work was carried out on male guinea pigs. After completion of the experiment, stria vascularis of inner ear was subjected to electron microscopic examination. In the control group (receiving gentamycin sulfate in an ototoxic dose), signs of blood flow disturbance were revealed, as well as ultrastructural changes in stria's vascularis cells (expansion of intercellular space, deformation of organelles, thinning of glycocalyx, blebbing). Also, fragmented cells were found. These changes are characteristics for apoptosis. In experimental group (receiving gentamycin sulfate and melaxen), degenerative changes were less pronounced. An increase of cell's secretory activity was observed. Changes in stria's vascularis cells by using melaxen are less pronounced. Increase of cell's secretory activity in stria vascularis is a compensatory reaction and saves auditory function.

Regulation of Krüppel-like factor 6 via activating transcription factor 4 pathway to apoptosis of human lens epithelial cells

Objective To investigate the regulating effects of Kruppel-like factor 6 (KLF6) on the apoptosis of human lens epithelial cells (HLECs) by activating transcription factor 4 (ATF4) pathway and explore the bio-molecular mechanism of KLF6/ATF4-induced HLECs apoptosis. Methods HLECs (HLE-B3) were cultured using high glucose DMEM medium.The eukaryotic expression plasmid pEGFP-C2-ATF4 was transfected into the cells by liposome 2000 in the ATF4-transfected group, and pEGFP-C2 was transfected in the empty plasmid group.Then the cells were exposed to 20 mJ/cm2 ultraviolet ray B (UVB) for 200 seconds, The morphological changes of the cells were observed by hematoxylin & eosin staining and Hoechst33258 fluorescein staining.Cultured cells were transfected using pEGFP-C2-KLF6 and pEGFP-C2 plasmid and pSilencer-KLF6 (siKLF6) and pSilencer plasmid, respectively, and the expression of ATF4 protein in the cells was detected by Western blot assay.Culture cells were divided into four groups.pEGFP-C2 and pSilencer plasmids were co-transfected into the cells in the empty plasmid group; pEGFP-C2-KLF6 and pSilencer empty plasmid were co-transfected into the cells of the KLF6+ pSilencer group; pEGFP-C2 empty plasmid and pSilencer-ATF4 were co-transfected in the cells of the siATF4+ pEGFP-C2 group; pEGFP-C2-KLF6 and pSilencer-ATF4 plasmids were co-transfected in the cells of the KLF6+ siATF4 group, and then the cells were exposed to UVB.The apoptosis of the cells were detected by ELISA assay. Results Cultured cells grew well in the normal control group with the uniform morphology and regular arrangement.The karyopyknosis, karyorrhexis and enlargement of intercellular space were found in the cells exposed to UVB.In the ATF4 transfected group, the number of cells was decreased.The relative expression level of the ATF4 protein in the cells was 0.99±0.06 and 0.13±0.02 in the UVB+ ATF4 transfected group and UVB+ pEGFP-C2 plasmid group, respectively, with a significant difference between them (t=23.13, P<0.01). The relative expression levels of KLF6 and ATF4 proteins in the KLF6 transfected group were higher than those in the empty plasmid group, and the relative expression levels of KLF6 and ATF4 proteins in the siKLF6 group were significantly lower than those in the empty plasmid group (all at P<0.01). ELISA assay showed that the apoptotic rate in the ATF4 transfected group was 1.37±0.11, which was significantly higher than 0.31±0.11 in the normal control group (t=8.034, P=0.001); the apoptotic rate of the cells was increased in the KLF6+ pSilencer group and decreased in the siATF4+ pEGFP-C2 group in comparison with the empty plasmid group (P<0.01, P=0.02). In addition, the apoptotic rate in the KLF6+ siATF4 group was remarkably lower than that in the KLF6+ pSilencer group (P<0.01). Conclusions KLF6 promotes the apoptosis of HLECs induced by UVB radiation.Silence of ATF4 gene reduces the apoptotic rate of the cells.ATF4 is probably a target factor in the regulating pathway of KLF6 to apoptosis. Key words: Kruppel-like factor 6; Kruppel-like transcription factors/metabolism; Activating transcription factor 4; Epithelial cells, lens; Cell line, crystalline; Humans; Apoptosis

Induction of chorioretinopathy by adrenaline injection in different strains of rabbits

Objective To establish a central serous chorioretinopathy(CSC) model on different strains of rabbits by intravenous injection of adrenaline, which may contribute to related researches of CSC. Methods This study was approved by Bioethics Committee of Fourth Military University and complied with Statement for the Use of Animals in Ophthalmic and Visual Research.Fundus fluorescein angiography(FFA) was initially performed on male New Zealand white rabbits (10), Belgium rabbits (5) and Chinchilla rabbits(10) to make sure that the retinas of subjects were normal.For the New Zealand white rabbits, adrenaline was injected via ear vein at a dose of 0.04 mg/kg once per day for the first 8 weeks and followed by a dose of 0.08 mg/kg for the next 4 weeks, while 0.04 mg/kg adrenaline was injected in the same way for 8 weeks in the Belgium rabbits and Chinchilla rabbits.FFA was performed every week after injection of adrenaline to evaluate the fluorescence leakage in ocular fundus.New Zealand white rabbits were sacrificed in 4 (3 rabbits), 8 (3 rabbits) and 12 weeks (4 rabbits) after injection respectively, and Belgium rabbits and Chinchilla rabbits were sacrificed in the 8 weeks after injection.The eyeballs of the rabbits were enucleated to prepare the retinal sections for histopathological examination after hematoxylin-eosin staining.The results of FFA and retinal structure were compared among different strains of rabbits. Results No fluorescence leakage was found by FFA in ocular fundus, and the retinal structure was normal in all the 10 New Zealand white rabbits during the experiment.Fluorescence leakage was found by FFA in 2 Belgium rabbits at 1 week and 2 weeks after injection respectively, and retinal detachment and depigmentation of retinal pigment epithelium (RPE) with an enlarged intercellular space were shown by hematoxylin-eosin staining.For the Chinchilla rabbits, fluorescence leakages were found in 7 rabbits throughout the whole period of adrenaline administration.Circumscribed retinal detachment, depigmentation of RPE with enlarged intercellular space were also found in leakage lesions. Conclusions Repeated intravenous injection of adrenaline can induce CSC-like lesions in colored rabbits but not in albino rabbits. Key words: Adrenaline; Central serous chorioretinopathy; Disease model, animal/drug induction; Fundus fluorescein angiography; New Zealand rabbit; Belgium rabbit; Chinchilla rabbit

Morphological characteristic and assessment of changesin the main structural components of the histohematological barrier of the thyroid tissue in cases of the sudden cardiac death from alcoholic cardiomyopathy

A retrospective analysis of acts of forensic medical autopsies from the archive of St. Petersburg GBUS BSME and a histological study of thyroid gland tissue in 188 cases (95 women and 93 men) were carried out with statistical processing of the obtained results for the purpose of studying and assessing the morphological changes in the main components of the histohematological barrier of thyroid gland tissue in cases of the sudden cardiac death from alcoholic cardiomyopathy. The decrease in the weight of the thyroid gland in the investigated cases and the revealed morphological signs, indicative of a decrease in the memory function of the thyroid gland were found and can be caused by the prolonged toxic effect of ethanol and its metabolites. Morphological changes in the endothelial lining of the vessels of the microcirculatory bed are caused both by the direct cytotoxic action of ethanol and its metabolites and by the action of mediators, the release of which occurs as a result of stimulation of the reactive cells, which leads to swelling, deformation and increased activity of endothelial cell membranes with the expansion of intercellular spaces and the development of increased permeability of the endothelial lining, which, in its turn, contributes to disruption of electrolyte transport and nutrients transport with changes trophism thyroid gland tissue, which is a substrate for the appearance of dystrophic and necrobiotic processes in main structural components of the histogematogenous barrier of the thyroid gland. The revealed morphological changes in thyroid gland tissue in cases of death from alcoholic cardiomyopathy have a non-specific nature and should be considered in conjunction with other visceral manifestations that are a reflection of alcohol intoxication during the chronic alcoholism.

Usefulness of high-speed digital imaging (HSDI) in the diagnosis of oedematous - hypertrophic changes of the larynx in people using voice occupationally.

The aim of the study is the evaluation of the usefulness of High-Speed Digital Imaging (HSDI) in the diagnosis of organic dysphonia in a form of oedematous-hypertrophic changes of vocal fold mucosa, morphologically confirmed by Transmission Electron Microscopy (TEM) method in patients working with voice occupationally. The group consisted of 30 patients working with voice occupationally with oedematous-hypertrophic changes of vocal fold mucosa. Parameters of vocal folds vibrations were evaluated using HSDI technique with a digital HS camera, HRES Endocam Richard Wolf GmbH. The image of vocal folds was recorded with a rate of 4000 frames per second. Postoperative material of the larynx was prepared in a routine way and observed in transmission electron microscope OPTON 900-PC. HSDI technique allows to assess the real vibrations of vocal folds and determine many parameters. The results of TEM in the postoperative material showed destruction of epithelial cells with severe vacuolar degeneration, the enlargement of intercellular spaces and a large number of blood vessels in the stroma, which indicates the presence of oedematous-hypertrophic changes of the larynx. The ultrastructural assessment confirm the particular usefulness of HSDI method in the diagnosis of organic dysphonia in a form of oedematous-hypertrophic changes. Key words: High-Speed Digital Imaging, oedematous-hypertrophic changes, vocal fold mucosa, larynx.