Cell Conglomerates Research Articles

Synthetic Data Generation for Morphological Analyses of Histopathology Images with Deep Learning Models

In this study, we introduce a new synthetic data generation procedure for augmentation of histopathology image data. This is an extension to our previous research in which we proved the possibility to apply deep learning models for morphological analysis of tumor cells, trained on synthetic data only. The medical problem considered is related to the Ki-67 protein proliferation index calculation. We focused on the problem of cell counting in cell conglomerates, which are considered as structures composed of overlapping tumor cells. The lack of large and standardized data sets is a critical problem in medical image classification. Classical augmentation procedures are not sufficient. Therefore, in this research, we expanded our previous augmentation approach for histopathology images and we proved the possibility to apply it for a cell-counting problem.

Investigating the Impacts of UVC Radiation on Natural and Cultured Biofilms: An assessment of Cell Viability.

Biofilms are conglomerates of cells, water, and extracellular polymeric substances which can lead to various functional and financial setbacks. As a result, there has been a drive towards more environmentally friendly antifouling methods, such as the use of ultraviolet C (UVC) radiation. When applying UVC radiation, it is important to understand how frequency, and thus dose, can influence an established biofilm. This study compares the impacts of varying doses of UVC radiation on both a monocultured biofilm consisting of Navicula incerta and field-developed biofilms. Both biofilms were exposed to doses of UVC radiation ranging from 1626.2 mJ/cm2 to 9757.2 mJ/cm2 and then treated with a live/dead assay. When exposed to UVC radiation, the N. incerta biofilms demonstrated a significant reduction in cell viability compared to the non-exposed samples, but all doses had similar viability results. The field biofilms were highly diverse, containing not only benthic diatoms but also planktonic species which may have led to inconsistencies. Although they are different from each other, these results provide beneficial data. Cultured biofilms provide insight into how diatom cells react to varying doses of UVC radiation, whereas the real-world heterogeneity of field biofilms is useful for determining the dosage needed to effectively prevent a biofilm. Both concepts are important when developing UVC radiation management plans that target established biofilms.

Cultivation of cells in alginate drops as a high-performance method of obtaining cell spheroids for bioprinting

Purpose of the study. Testing the protocol of obtaining cell spheroids of breast cancer cell cultures for bioprinting by growing in alginate drops.Materials and methods. Cells of breast cancer cell lines BT-20 and MDA-MB-453 were cultured in DMEM medium supplemented with 10 % FBS. Next, the cells were removed from the plastic using a trypsin-V ersene solution and resuspended in a sterile 2 % alginate solution in DPBS to the concentration of 105 cells/ml. Then the alginate solution with the cells was slowly dripped through a 30G needle into a sterile cooled solution of calcium chloride (100 mM) from a height of 10 cm. After polymerization, alginate drops were washed in DMEM and cultured for two weeks in DMEM with the addition of 10 % FBS at 37 °C and 5.0 % CO2.The spheroids formed in the alginate were photographed on the 3rd, 7th, 10th, and 14th days of cultivation, after which they were removed from the alginate by keeping in 55 mM sodium citrate solution with the addition of 20mM ethylenediaminetetraacetic acid (EDTA) and embedded in paraffin blocks according to the standard method, followed by histological examination.Results. Cellular spheroids were formed in both cell cultures already on the 3rd day of cultivation. From the 3rd to the 10th day in both cultures, a uniform growth of cell spheroids was observed with a gradual slowdown in the increase in the size of spheroids by the 14th day of cultivation. On the 10th day the proportion of cells that formed clones (more than 500 μm2 in size) was 25.2 % ± 7.1 % (n = 25) in the BT-20 culture and 38.5 % ± 9.9 % (n = 25) in MDA-MB-453 culture. On the 14th day, BT-20 culture was characterized by spheroids varying little in size and shape, with an average area of 1652 ± 175 µm2, having a dense structure with smooth edges. The spheroids in MDA-MB-453 culture turned out to be more loose and easily deformed, their size and shape varied noticeably, the average area of the spheroids was 2785 ± 345 µm2.Conclusion. The production of spheroids in alginate drops is inferior in speed to the methods of forming cell conglomerates in hanging drops or on microwells, but it surpasses these methods in productivity, which is comparable to the production of spheroids by constant medium stirring on low-adhesive substrates. In addition, the clonal nature of the obtained spheroids leads to an increase in research costs and thus limits their scalability.

APPLICATION OF SILICONE COATING TO OPTIMIZE THE PROCESS OF OBTAINING CELLULAR SPHEROIDS BY THE HANGING DROP METHOD

Purpose of the study . To study the effect of SIEL 159–330 coating on the cell clusters formation rate in a hanging drop method in combination with the use of methylcellulose (MC) and collagen as cell aggregation improving agents. Materials and methods . BT20 breast cancer cells were cultured in drops of 20 μL (104 cells per drop) on the lid of a polystyrene Petri dish coated with SIEL 159–330 silicone elastomer (GNIIKHTEOS, Moscow, Russia) or without coating. The study tested three concentrations of MC (0.1 %, 0.25 % and 0.4 %) and collagen (150 µg/ml, 300 µg/ml and 600 µg/ml). The rate of formation of cell conglomerates was assessed by evaluating their area after 4, 24, 48, and 72 hours of cultivation. Results . The use of SIEL 159–330 coating made it possible to obtain spheroids of the same size as the addition of 0.4 % MC over a time interval of 72 hours. The silicone coating additionally reduced the size of cell spheroids in the medium with 0.1 % MC at all time points; however, this effect disappeared with increasing concentration of MC. In addition, the use of SIEL 159–330 reduced the relationship between the size of cellular spheroids and the concentration of MC, which allows us to consider the use of this coating as an alternative to MC or a way to reduce its concentration. In the experiment with the addition of collagen to the culture medium, the sizes of cell conglomerates formed on the silicone coating were significantly smaller than on uncoated plastic in all variants of the experiment and time points. The effect was more pronounced for a collagen concentration of 600 μg/ml. The use of SIEL 159–330 coating, in addition, reduced the variability in the size and shape of the resulting cell conglomerates. Conclusion . Accelerated aggregation of cells and fibers of the extracellular matrix in hanging drops, as well as a reduction in the variability in the size and shape of the resulting cell clusters on SIEL 159–330, allows us to reduce the time of experiments and material costs, as in experiments with the addition of substances that accelerate the formation of spheroids (MC and collagen), as well as in their absence.

Terpenes Combinations Inhibit Biofilm Formation in Staphyloccocus aureus by Interfering with Initial Adhesion.

The biofilm is a conglomerate of cells surrounded by an extracellular matrix, which contributes to the persistence of infections. The difficulty in removing the biofilm drives the research for new therapeutic options. In this work, the effect of terpenes (−)-trans-Caryophyllene, (S)-cis-Verbenol, (S)-(−)-Limonene, (R)-(+)-Limonene, and Linalool was evaluated, individually and in combinations on bacterial growth, by assay with resazurin; the formation of biofilm, by assay with violet crystal; and the expression of associated genes, by real-time PCR, in two clinical isolates of Staphyloccocus aureus, ST30-t019 and ST5-t311, responsible for more than 90% of pediatric infections by this pathogen in Paraguay. All combinations of terpenes can inhibit biofilm formation in more than 50% without affecting bacterial growth. The most effective combination was (−)-trans-Caryophyllene and Linalool at a 500 μg/mL concentration for each, with an inhibition percentage of 88%. This combination decreased the expression levels of the sdrD, spa, agr, and hld genes associated with the initial cell adhesion stage and quorum sensing. At the same time, it increased the expression levels of the cap5B and cap5C genes related to the production of capsular polysaccharides. The combinations of compounds tested are promising alternatives to inhibit biofilm formation in S. aureus.

Biofilm-a Syntrophic Consortia of Microbial Cells: Boon or Bane?

Biofilm is the conglomeration of microbial cells which is associated with a surface. In the recent times, the study of biofilm has gained popularity and vivid research is being done to know about the effects of biofilm and that it consists of many organisms which are symbiotic in nature, some of which are human pathogens. Here, in this study, we have discussed about biofilms, its formation, relevance of its presence in the biosphere, and the possible remediations to cope up with its negative effects. Since removal of biofilm is difficult, emphasis has been made to suggest ways to prevent biofilm formation and also to devise ways to utilize biofilm in an economically and environment-friendly method.

“Hominids with an Infected Brain” Engage in Viral Debate: Agamben and Žižek on the Impact of the Coronavirus Pandemic on Human Relationships

“Hominids with an Infected Brain” Engage in Viral Debate: Agamben and Žižek on the Impact of the Coronavirus Pandemic on Human Relationships

Exploring the potential of taurolidine in inducing mobilization and detachment of colon cancer cells: a preliminary in-vitro study

BackgroundRecently, taurolidine has been intensively studied on a variety of in-vitro cancer cell-lines and first data exhibit encouraging antitumoral effects. While the clinical use of taurolidine is considered, some studies with in-vivo experiments contradict this beneficial effect and even indicate advanced cancer growth. The aim of this study is to further investigate this paradox in-vivo effect by taurolidine and closely analyze the interaction of cancer cells with the surrounding environment following taurolidine exposure.MethodsHT-29 (ATCC® HTB-38™) cells were treated with taurolidine at different concentrations and oxaliplatin using an in-vitro model. Morphological changes with respect to increasing taurolidine dosage were visualized and monitored using electron microscopy. Cytotoxicity of the agents as well as extent of cellular detachment by mechanical stress was measured for each substance using a colorimetric MTS assay.ResultsBoth taurolidine and oxaliplatin exhibit cell toxicity on colon cancer cells. Taurolidine reshapes colon cancer cells from round into spheric cells and further induces cluster formation. When exposed to mechanical stress, taurolidine significantly enhances detachment of adherent colon carcinoma cells compared to the control (p < 0.05) and the oxaliplatin group (p < 0.05). This effect is dose dependent.ConclusionsBeside its cytotoxic effects, taurolidine could also change mechanical interactions of cancer cells with their environment. Local cancer cell conglomerates could be mechanically mobilized and may cause metastatic growth further downstream. The significance of changes in cellular morphology caused by taurolidine as well as its interaction with the microenvironment must be further addressed in clinical cancer therapies. Further clinical studies are needed to evaluate both the safety and efficacy of taurolidine for the treatment of peritoneal surface malignancies.

Cell Adaptations of Rhodococci to Pharmaceutical Pollutants

Against the background of atense environmental situation, the risk of drug pollution in the natural environment is steadily increasing. Pharmaceuticals entering open ecosystems can cause toxic effects in wildlife from molecular to population levels. The aim of this research was to examine the impact of pharmaceutical pollutants on rhodococci, which are typical representatives of soil actinobacteria and active biodegraders of these compounds. The pharmaceutical products used in this research werediclofenac sodium and ibuprofen, which are non-steroidal anti-inflammatory drugs (NSAIDs) that are widely used and frequently found in the environment. The most common cell adaptations of rhodococci to the effects of NSAIDs were changes in zeta potential, catalase activity, morphometric parameters and degree of hydrophobicity; elevated contents of total cellular lipids; and the formation of cell conglomerates. The findings demonstrated the adaptation mechanisms of rhodococci and their increased resistance to the toxic effects of the pharmaceutical pollutants.&#x0D; Keywords: pharmaceutical pollutants, NSAIDs, diclofenac, ibuprofen, cell responses, Rhodococcus

Peculiarities of the ultrastructure of mixed biofilms of the causing agent of diphtheria and conditionally pathogenic microorganisms isolated from the human respiratory tract.

Modeling of the biofilm formation process was carried out using the strains C.diphtheriae gravis tox+№. 665, C.pseudodiphtheriticum, S.aureus. Biofilm samples were placed on the stage of a scanning electron microscope and gold-sputtered in an EicoIB-3 ioncoater vacuum deposition unit (Eico, Japan) at an ion current of 6-8 mA. The samples obtained were examined in a JEOL 6510LB scanning electronmicroscope. («JEOL» company, Japan) at an accelerating voltage of 30 kV. Electron microscopic examination of samples of biofilms C. diphtheriae gravis tox+ № 665 and opportunistic microorganisms shows groups of 2-7 young bacterial cells packed into a single microcapsule. Much more voluminous accumulations of bacterial cells (more than 10-12) are typical for biofilm samples represented by C. diphtheriae gravis tox+№ 665 and S. aureus cells. On the surface of the biofilm, young bacterial cells with an intact structure are located at various stages of active division. The conglomerates of bacterial cells, covered with a common intermicrobial matrix, adhere tightly to each other and form a multilayer biofilm. Features of the ultrastructure of biofilms containing strains of C. diphtheriae and opportunistic bacteria, especially antibiotic-resistant bacteria inhabiting the respiratory tract, can contribute to long-term persistence of the pathogen of diphtheria in the body. They not only significantly complicate the access of antibacterial drugs, but also interfere with the isolation of C.diphtheriae during bacteriological research.

The study of biotechnological potential of &lt;i&gt;Lactobacillus sakei&lt;/i&gt; LSK-103

Lactic acid bacteria play an important role in the production of food. Bacterial cultures widely used in the food industry often have a set of characteristics that ensure the stability of the production. The biotechnological properties of Lactobacillus sakei LSK-103 have been studied in the present work. Lactobacillus sakei LSK-103 has shown high biochemical activity on MRS medium. It has been found that after 16 h of cultivation at the end of the exponential growth phase, the number of viable bacterial cells reaches 10 CFU/cm. The study of the effect of different concentrations of sodium chloride on biomass accumulation has shown that Lactobacillus sakei LSK-103 is highly resistant to salt. Increase in NaCl concentration from 2 to 10 % leads to decrease in cell survival from 96.8 to 91.2 %, and in number of bacteria to 10 CFU/cm. Morphological studies indicate that an increase in the concentration of sodium chloride in the medium is accompanied by cell cohesion, the formation of cell conglomerates. Cohesion intensifies intercellular contacts and increases the resistance of Lactobacillus sakei LSK-103 to osmotic stress. The high survival rate of Lactobacillus sakei LSK-103 has been shown in the presence of bile, phenol (0.4 %), high (pH 8.3) and low (pH 3.5) values of active acidity of the medium indicating its probiotic properties. The results of research have shown that the Lactobacillus sakei LSK-103 has high biotechnological potential and can be used as part of bacterial preparations for the production of fermented fish products.

Digital Microscopy Technologies: A Method for Constructing Incision Lines on Cell Conglomerate Images

The article is devoted to the technology of separating conglomerates of leukocyte cells in digital microscopy images of bone marrow preparations in the light range for determining the number of cells and automatic diagnosing. A special feature of the proposed method is the use of the principle of separating cell conglomerates based on abnormal points. The key points of the method: the determination of the cell conglomerate contour, the detection of abnormal points, and sectioning the cell conglomerate image by the bisector of the angle whose vertex is the abnormal point. The parameters providing necessary accuracy of cell conglomerate separation are determined. Here the accuracy is understood as a fraction of correctly separated cells in the images of bone marrow preparations with respect to the total number of cells in the images used in the experiment. Images containing cell conglomerates forming chains were considered. The experiment confirmed the efficiency of the proposed method. The separation accuracy of adjacent cells is 95%.

Influence of calcium ions on physical chemical characteristics of semiconductor quantum dots encapsulated by amphiphilic polymer and their efficiency of cellular uptake

Here, we studied the effect of calcium ions on the physicochemical properties and cellular uptake of CdSe/ZnS quantum dots encapsulated with poly(maleic anhydride-alt-1-tetradecene), modified to a varying extent by quaternary ammonium groups. It was shown that quantum dots carrying negatively charged carboxyl groups in the polymer shell change their physicochemical and optical characteristics in the presence of Ca2+ and Ba2+ ions. As the negatively charged carboxyl groups in the shell are completely replaced by positively charged quaternary ammonium groups, these effects gradually decrease. A change in the physicochemical properties of nanoparticles leads to a change in their cellular uptake in the presence of calcium ions. Nanoparticles carrying only negatively charged groups in the shell in the presence of Ca2+ agglomerate and form conglomerates of nanoparticles and cells. The positively charged quaternary ammonium groups in the polymer shell of the nanoparticles increase their aggregative stability in the presence of Ca2+ and contribute to their uptake by cells. The mechanisms of uptake depend on nanoparticle’s charge. Nanoparticles with a positive ζ potential are absorbed by calcium-dependent mechanisms, which are suppressed by inhibition of the calcium-dependent enzyme dynamin or in the presence of calcium chelator EGTA. The uptake of nanoparticles with a negative ζ potential, in contrast, is enhanced by the chelation of calcium ions. This indicates the different role of cellular calcium-dependent mechanisms in the uptake of positively and negatively charged nanoparticles.

Grafted polymer brush coatings for growth of cow granulosa cells and oocyte-cumulus cell complexes.

In the present work, three types of grafted brush coatings [P4VP, POEGMA246, and P(4VP-co-POEGMA246)] were successfully fabricated using graft polymerization of monomers "from the surface." The composition, thickness, and morphology of the grafted brush coatings were analyzed by TOF-SIMS, ellipsometry, and AFM, respectively. The chemical nature of the polymer surface plays a crucial role in the growth and development of the cow granulosa cells and, therefore, also oocyte-cumulus complexes. In comparison with other coatings, the P(4VP-co-POEGMA246) copolymer coating enables the formation of dispersed and small but numerous cell conglomerates and high cumulus expansion in oocyte-cumulus complexes with highly homogeneous cumulus layers surrounding the oocytes. Moreover, the cellular oxygen uptake for this coating in the presence of NaF (inhibitor glycolysis) was stimulated. This new (4VP-co-POEGMA246) copolymer nanostructured coating is a promising material for granulosa cell and oocyte-cumulus complex cultivation and possibly will have great potential for applications in veterinary and reproductive medicine.

ВЛИЯНИЕ КАДМИЯ НА ГЕМАТОЛОГИЧЕСКИЕ ПОКАЗАТЕЛИ КАРПА

The article is devoted to the assessment of the toxic effects of cadmium acetate on fish. The research topic is relevant, since heavy metals, and especially cadmium, are ones of the most dangerous pollutants for the aquatic environment. After the emission of the already used water by the electricity-power plants into the reservoirs of circulating wa-ter, a sharp increase in the maximum permit-ted concentrations of heavy substances can be observed often, which act on hydrobi-onts for a rather short period of time. That is why, modeling this effect is necessary to study the effects of heavy metals. The aim of the assay was to study the hematological parameters of carp after exposure to various concentrations of cadmium acetate. During the experiment, 5 groups of fish were formed - 1 control group (10 fish), 4 experimental groups - 10 fish each. The experimental groups of fish were exposed in a solution of cadmium acetate (Cd (CH3COO) 2) with concentrations of 0.05 mg / l, 0.5 mg / l, 5 mg / l, 50 mg / l (exceeding the maximum permissible concentration of cadmium for fisheries in 10, 100, 1000 and 10000 times respectively). We have investigated: the erythrocyte sedimentation rate, the number of red blood cells in the blood and the con-centration of hemoglobin in the blood. Dur-ing the study, the authors noted an increase in the erythrocyte sedimentation rate due to the formation of conglomerates of blood cells with plasma proteins, as well as a de-crease in the number of red blood cells due to the toxic effect of cadmium acetate. A decrease in the concentration of hemoglobin in the blood was also observed, probably associated with a decrease in the number of red blood cells due to their lysis. With an increase in the concentration of the metal under study, there is a significant increase in ESR, a decrease in the level of hemoglobin and the number of red blood cells.

91 Mitral fracking: an unusual complication of infective endocarditis

Abstract The conglomerate of microorganisms, inflammatory cells, fibrin and platelets that constitutes the characteristic lesion of infectious endocarditis, that is, vegetation, was considered as a major criterion of infectious endocarditis in the 90s thanks to the development of ultrasound. Ecocardiography allows the diagnosis of complications derived from the infection, such as valvular perforation, prosthetic dehiscence, fistula or abscesses. One of the most infrequent complications is the mitral pseudoaneurysm. It has its origin in the impact of a jet of aortic regurgitation on the anterior leaflet of the mitral valve, which is why we have called it mitral fracking. A 60-year-old man who had a recent history of pneumonia and for whom he was still receiving antibiotic treatment, debuted suddenly with dyspnea of minimal effort. He went to a cardiology clinic where he was found to have severe mitral regurgitation. He was directly derived to cardiac surgery of our hospital. Prior to the intervention, a transesophageal ultrasound study was performed in our department, which showed the following findings: a bicuspid aortic valve with a small vegetation on its aortic surface (Figure A, surgical piece), a protuberance on the anterior mitral leaflet (Figure B) with internal flow that caused systolic expansion towards the atrium (Figure C) and diastolic collapse towards the ventricle (figure D): the mitral pseudoaneurysm. The therapeutic action was based on the replacement of both valves with mechanical prostheses. The blood cultures were negative, but the surgical piece revealed unequivocal histological findings of infectious endocarditis. Currently, the patient is stable and the valves are normofunctional in the regular follow-up controls. Abstract 91 Figure.

Quantitative and Compositional Study of Monospecies Biofilms of Spoilage Microorganisms in the Meat Industry and Their Interaction in the Development of Multispecies Biofilms.

Food spoilage is a serious problem in the food industry, since it leads to significant economic losses. One of its main causes is the cross-contamination of food products from industrial surfaces. Three spoilage bacterial species which are highly present in meat and the gastrointestinal tract of chickens were selected: Pseudomonas fragi, Leuconostoc gasicomitatum, and Lactobacillus reuteri. The dual aim was to determine their ability to form monospecies biofilms and to examine how they interact when they coexist together. To do so, mature monospecies biofilms were produced statically for seven days at a temperature of 30 °C. L. gasicomitatum was also used to investigate the behavior of P. fragi and L. reuteri in the formation of multispecies biofilms. The structure and composition of the monospecies biofilms were evaluated by direct epifluorescence microscopy, and the multispecies biofilms were evaluated by plate counting. Both L. gasicomitatum and L. reuteri were able to form biofilms, with counts of approximately 7 Log CFU/cm2 and a defined structure. However, P. fragi obtained counts to the order of 4 Log CFU/cm2, which is significantly different from the previous species (P < 0.05), and it had no network of cell conglomerates. The content of the L. gasicomitatum and L. reuteri biofilm matrices were 70–80% protein, unlike P. fragi, which presented a higher polysaccharide content (P < 0.05). In the multispecies biofilms, the presence of P. fragi did not affect the growth of L. gasicomitatum, which remained at between 5.76 to 6.1 Log CFU/cm2. However, L. reuteri was able to displace L. gasicomitatum growth after 24 h of coexisting in a mixed biofilm, presenting differences in counts of approximately 2 Log CFU/cm2. The study of the biofilms constructed by food industry resident microbiota can help to understand the ecological relations that exist between species, characterize them, and propose strategies to eliminate them. The name of genes and species should be written in italic.

The Effect of Nutrition on Immune System Review Paper

The most basic definition of immunity is the ability of the organism to resist the invasion of microorganisms and harmful substances. Blood plays an important role in immune development due to the presence of certain types of white blood cells in the blood and in some other tissues have the ability to eliminate strange organisms and destroy it as well the blood plasma contains antibodies made by certain immune cells to resist any strange proteins or any other substances linked to proteins, such proteins that stimulate the body tissues to form antibodies called antigen generators or antigens.Some objects work on precipitation these strange proteins to isolate them, so it called precipitins, while others work on the conglomerate of microorganisms or red blood cells. These are called agglutinins, while some act on neutralizing of toxins, called antitoxins.Immunizations are either natural immunity or innate immunity or acquired immunity. When the body resists the invasion of a particular species of microorganisms for the first time, it will have natural immunity, But the immunity acquired by the individual as a result of immunizations or vaccination of such microorganisms is known as acquired immunity, However, acquired immunity may be natural or artificial. The immunity generated in the individual an actual measles infection is known as naturally acquired immunity, but the immunity that is formed as a result of vaccinating the individual of typhoid or diphtheria vaccine is artificially acquired immunity (1, 2, 3, 4, 5).However, acquired immunity may be natural or artificial. The immunity generated in the individual following an actual measles infection is known as naturally acquired immunity (6). DOI : 10.7176/FSQM/90-06 Publication date :September 30 th 2019

Clinical and molecular markers in retinal detachment-From hyperreflective points to stem cells and inflammation.

PurposeRetinal detachment (RD) is one of the most frequently diagnosed ophthalmologic conditions requiring prompt surgical intervention. Combination of proper surgical technique and new diagnostic markers, both clinical and molecular, can help improve the diagnosis and prognosis of RD treatment.Methods12 patients with rhegmatogenous RD (rRD) were included into the study after obtaining patient consent and Regional Ethical Approval (average age: 58.1 ± 17.4 years). OCT was performed before and after 23G vitrectomy for RD. Pure subretinal fluid (SRF) was collected during surgery and analyzed by protein array profiling on a panel of 105 inflammatory cytokines (Human XL Cytokine Array), while the effect of SRF upon human macrophages-driven phagocytosis of apoptotic retinal pigment epithelial (RPE) cells ex vivo was quantified by flow cytometry. Immunohistochemistry (IHC) of retinectomized tissue due to PVR caused by RD was performed to determine presence of markers for microglial cells (CD34), macrophages and activated microglia (CD68), regulator of the immune response to infection (NFkB), progenitor and stem cell marker (Sox2), pluripotency marker (Oct4) and intermediate filament markers (GFAP and Nestin).ResultsOCT of fresh RD patients contained pre-operatively hyper reflective points (HRPs) at the detached neuroretina border and proximal to the RPE layer—their size and number decreased following successful reattachment surgery. IHC of the retinectomized tissue from detached retina due to severe PVR showed presence of cell conglomerates at the detached neuroretina border which were positive for CD68, NFkB, Sox2 and GFAP, less positive for CD47 and Nestin and negative for Oct4 and CD34. The SRF contained at least 37 cytokines with higher, and 4 cytokine with lower concentration compared to that in vitreous from non-RD pathology; when used as conditional medium to human macrophages ex vivo, the SRF doubled their capacity for engulfing dying RPEs.ConclusionsFresh RD can be hallmarked by presence of HRPs at the detached neuroretina border on OCT; the HRPs decrease in size and number after successful reattachment surgery, and likely resemble the macrophage conglomerates seen by IHC. The neuroretina in RD contains progenitor/stem-like cells and signs of inflammatory reaction, while the SRF contains inflammatory cytokines and other factors which increase the ability of professional phagocytes to engulf dying RPE, or for that matter, other dying cells in the retina.

How diatom Cylindrotheca closterium vanquish invasive copepod Oithona davisae

Some diatoms are rich food for herbivorous copepods, while others are toxic for their recruitment. No negative effect of diatom Cylindrotheca closterium was ever observed for copepods, and some estuarine copepods preferred it as a food. Data on grazing diatoms by abundant now in the Black Sea coastal waters invasive copepod Oithona davisae are still contradictory. Interaction of O. davisae and C. closterium, both having high colonizing potential and both typical for coastal waters, was studied in experimental culture. Two weeks after inoculation of C. closterium the cultured O. davisae was drastically fouled by globulous conglomerates of diatom cells. Diatom cells in “colonies” on copepod exoskeleton were interconnected by means of adhesive substances at one of their flexible ends at the point-wise areas at various parts of copepods exoskeleton, and the opposite flexible ends performed various circular roll-over fan-shaped movements around the axis passing through the point of their attachment. “Colonies” behaved as integrated aggressive organisms against any approaching flagellate and prevented normal locomotion of copepods. Herein we present the first report on epizoic behavior of C. closterium: quick disastrous colonization of alive copepods O. davisae by diatom “colonies” led to total extinction of cyclopoid experimental population while alive diatoms formed dense network on copepods degenerative tissues.