Internal Structure Of Cells Research Articles

Effect of Regulating the Expression of HSP47 on Collagen Metabolism in Scleral Fibroblasts

ABSTRACT Purpose To explore the effect of heat shock protein 47 (HSP 47) on collagen (types I, III, and V) metabolism in scleral fibroblasts. Methods Scleral fibroblasts with over- or low-expression of HSP 47 were constructed by plasmid transfection. The mRNA and intracellular proteins expression of HSP 47, collagen (types I, III, and V) and α-smooth muscle actin (α-SMA) were detected by quantitative real-time polymerase chain reaction and western blot. The proteins expression of collagen (types I, III, and V), matrix metalloproteinase 2 (MMP-2), and tissue inhibitor of matrix metalloproteinases 1 and 2 (TIMP-1 and −2) in extracellular matrix (ECM) were detected by ELISA. The migration and proliferation activities of cells were detected by scratch-wound assay and MTS. The internal structure of scleral fibroblasts was observed by transmission electron microscopy (TEM). Results The results obtained demonstrated significant increases in the expression of the mRNA and protein expression of collagen I in HSP47 up-regulated cells. Overexpression of HSP 47 promotes the expression of α-SMA and cell migration. Down-regulated expression of HSP 47 results in decreased mRNA and protein expression of collagen. Low expression of HSP 47 significantly inhibits cell migration and proliferation, and affects the internal structure of cells. Conclusion HSP 47 affects collagen metabolism in scleral fibroblasts. It appears to promote the synthesis and secretion of collagen I as well as inhibit degradation.

A study on the migration and internal structure of cells on the micro-grooved substrates

A study on the migration and internal structure of cells on the micro-grooved substrates

Investigation of the internal structure and dynamics of gum cancer cells, tissues and tumors by 13C–NMR spectra of DNA/RNA of gum cancer cells as an essential structural tool for integrative studies of gum cancer cells development

Investigation of the internal structure and dynamics of gum cancer cells, tissues and tumors by 13C–NMR spectra of DNA/RNA of gum cancer cells as an essential structural tool for integrative studies of gum cancer cells development

How Does the Internal Structure of Cardiac Muscle Cells Regulate Cellular Metabolism?

How Does the Internal Structure of Cardiac Muscle Cells Regulate Cellular Metabolism?

COMBINED EFFECT OF CADMIUM AND LOWERED SALINITY ON DYNAMICS OF ABUNDANCE AND PHYSIOLOGICAL PROCESSES FOR ALGA PLAGIOSELMIS PROLONGA

Combined effect of cadmium (10, 30, and 50 mg/L) and salinity (32, 24, and 16 ‰) on marine unicellular alga Plagioselmis prolonga (Cryptophyta) is investigated. Such parameters as the cells number dynamics, their size, side scattering (as a characteristic of internal structure of cells), photosynthetic pigments fluorescence (chlorophyll a, phycoerythrin, allophycocyanin, as a measure of the photosynthetic apparatus function), and reactive oxygen species (ROS) content (as an index of the cellular membranes destruction) were registered in experiments using the flow cytometer CytoFLEX (Beckman Coulter). Addition of cadmium in concentration of 10 mg/L to the water with salinity 32 ‰ did not influence on alga growth and its physiological parameters. The higher concentrations of cadmium, as 30 and 50 mg/L, stimulated the cells growth and ROS increased under the concentration of 50 mg/L, but other parameters did not altered. The same contamination with cadmium under salinity 24 ‰ caused the cells size rising and their intensive growth, ROS increasing on 3rd day and decreasing on 7th day of exposition, and phycoerythrin and allophycocyanin fluorescence diminishing, but the side scattering and chlorophyll a fluorescence still did not differ from the control. Any concentration of cadmium in the water with salinity 16 ‰ caused the population growth inhibition, decreasing of side scattering and all photosynthetic pigments fluorescence, and increasing of ROS and cells size. There is concluded that cadmium contamination in conditions of normal (32 ‰) salinity has a stimulation effect on Plagioselmis prolonga growth and no effect on its photosynthetic apparatus, but the same contamination in conditions of lowered salinity has a negative effect on both its growth and photosynthetic functions, whereas the reactive oxygen species content increases and the cells become larger under the cadmium contamination regardless the salinity factor.

Multi-Site Protein Subcellular Localization Based on Deep Convolutional Neural Network

Each part of internal structure of cells which is commonly mentioned as subcellular is highly ordered and interconnected has unique functions. The experiments show that deviated protein delivery to the corresponding subcellular causes of human disease. Studies of protein localization can clarify pathogenesis and find treatments. As protein subcellular localization has a very important position in the field of biology, the research in this area is extremely active. Most of the existing protein sub cellular localization methods are more suitable for single-site sub cellular localization. This paper proposed an algorithm based deep convolution neural network which is suit for multi-site protein subcellular localization and the algorithm is implemented on the human protein database to verify and analyze the performance. In order to further improve the classification result of the algorithm, it was combined ensemble learning and features fusion. It can be inferred from experiments that the proposed algorithm is effective in multi-site protein subcellular localization and the overall correct rate of classification is 59.13% which is higher than SAE, SVM and RF. The algorithm proposed in this paper is more uniform and less affected by the number of samples. When the data samples are different, the classification results will have a certain impact, but the overall classification is good. Besides ensemble learning and features fusion are effective for improving classification result.

Analysis of cell migration and internal structure of cells cultured on the micro-grooved substrate for application of cell sorting.

Analysis of cell migration and internal structure of cells cultured on the micro-grooved substrate for application of cell sorting.

Identification of pathogenicity-related genes and the role of a subtilisin-related peptidase S8 (PePRT) in authophagy and virulence of Penicillium expansum on apples

Blue mold caused by Penicillium expansum is a major postharvest disease of pome fruit. Several mechanisms possibly involved in P. expansum pathogenicity and virulence. However, factors that mediate pathogenicity and virulence are largely not yet characterized. In this work we analyzed P. expansum predicted secretome to reveal potential genes that have a role in host-pathogen interaction. A prediction pipeline was designed using an approach that combines common effector features, transcriptomic data and homology to proteins reported to be involved in pathogenicity of other pytopathogenic fungi. Among 297 genes predicted in P. expansum secretome, 103 genes (35%) were found to code for hydrolytic enzymes. The majority of the secreted enzymes are carbohydrate-degrading enzymes among which five coding for pectin-degrading enzymes are highly induced during the infection and decay of apple fruit by P. expansum, indicating that they may represent an important aspect of pathogenicity and virulence. Applying the pipeline we have predicted 17 candidate genes coding for proteins that are most likely involved in pathogenicity and virulence. One of the top candidates is a subtilisin-related peptidase, S8 (PePRT), proteolytic enzyme highly expressed in planta, and potentially involved in authophagy process. Deletion of PePRT-coding gene resulted in reduced virulence of P. expansum on apples. Moreover, ΔPeprt exhibited decreased sporulation as well as affected mycelial morphology and internal mycelial cell structure.

Sample Preparation for Transmission Electron Microscopy.

Transmission electron microscopy (TEM) is an ideal device to study the internal structure of cells and different types of biological materials, but adverse conditions inside electron microscopes such as damage induced by electron bombardment and vacuum evaporation of structural water necessitates complex preparation methods to survive this environment. In order to introduce the sample into the evacuated microscope column, it should be stabilized and altered to small enough (about 3 mm in diameter) and thin enough parts to permit the transmission of electrons. Depending on applications different thicknesses are required; for example, in biological research studies usually 300-500nm thickness isindicated. To stabilize the specimen and preserve the sample structures, different preparation methods are used involving different steps based on the type of study and the specimen, although theultimate goal of all these preparation technics is to maintain the native structure of the sample. In this chapter, we try to explain the series of steps that involve in preparation. Virtually every step can affect the quality of sample, and therefore it is important to execute each step in detail.

THE COMPARATIVE ANALYSIS OF THE ULTRASTRUCTURAL REACTION OF NEO- AND PALLEOCORTEX OF BRAIN ON ACUTE CEREBRAL DISORDER IN BASSIN OF CAROTID ARTERIES ON BACKGROUND OF DIABETIC ENCEPHALOPATHY IN RATS

The aim of the study. The objective is to perform the comparativ analysis the ultrastructural reactions of tissues of neocortex and fields of hippocampus in rats with diabetic encephalopathy to acute cerebrovascular disorder in the bassin of carotid arteries. Material and methods. Diabetes mellitus was modeled by single intraperitoneal administration of the streptozotocin (Sigma, Aldrich, 60 mg / kg) to white nonlinear male rats in age two months, and acute cerebrovascular disorder was performed by a 20-minute clipsing of both common carotid arteries under intraperitoneal anesthesia, with reperfusion for 1 hour. The fragments of the brain containing the hippocampus and the cortex of the frontal and occipital brain lobes were taken, and after appropriate fixation and wiring, ultrathin sections were made, which were stained with 1% aqueous uranyl acetate solution, contrasted by lead citrate and studied using an electron microscope PEM-125K. Results. The diabetic encephalopathy in rats exacerbates destructive changes of all structural components of the gray matter of the cortex of the investigated brain lobes and the fields of the hippocampus in the form of violations of the internal structure and shape of the nerve cells and the appearance of neurocytes with hypo and hyperchromia of neuro-and karyoplasma in varying degrees of severity, violation of the structure of cellular organelles and decrease their number, appearance of perivascular edema, that is caused by ischemia-reperfusion of the brain. Among the all studied structures, the field of the hippocampus CA3 is the least sensitive to the indicated intervention. Conclusions. Diabetic encephalopathy creates pathomorphological preconditions for the deteriorated course of ischemic-reperfusion injury of the brain, especially in the structures of the neocortex and the fields of the hippocampus CA1 and CA2.

Actin as a cytoskeletal basis for cell architecture and a protein essential for ecdysis in Prorocentrum minimum (Dinophyceae, Prorocentrales)

SUMMARYThe specific cell architecture of prorocentroid dinoflagellates is reflected in the internal cell structure, particularly, in cytoskeleton organization. Cytoskeleton arrangement in a Prorocentrum minimum cell was investigated using fluorescent labeling approaches, electron‐microscopy and immunocytochemical methods. The absence of cortical microtubules was confirmed. Phalloidin – tetramethylrhodamine isothiocyanate conjugate staining demonstrated that F‐actin forms a dense layer in the cortical region of the cell; besides, it was detected in the ‘archoplasmic sphere’ adjacent to the nucleus. In some cells the rest of the cytoplasm and the nucleus were also slightly stained. In dividing cells, F‐actin was mainly distributed in the cortical region and in the cleavage furrow. Fluorescent deoxyribonuclease I staining demonstrated more evenly distributed cytoplasmic non‐polymerized actin; the basis of the nuclear actin pool is monomeric actin. It concentrates in the nucleoplasm and forms a meshwork around chromosomes. The significant amount of G‐actin is apparently localized in the P. minimum nucleolus. Assumed involvement of F‐actin in the process of stress‐induced ecdysis – cell cover shedding – was examined. A sharp decrease in the level of ecdysis was observed after treatment with actin‐depolymerizing agent latrunculin B. The fluorescent staining of treated cells demonstrated disturbance of the actin cytoskeleton and disappearance of the cortical F‐actin layer. Our results support the recent data on the actin involvement in fundamental nuclear processes: cytoplasmic F‐actin appears to participate in cell shape determination, cell cover rearrangement and development. Actin may play a substitute role in the absence of cortical microtubules, representing the cytoskeletal basis of P. minimum cell architecture.

Concomitant use of polarization and negative phase contrast microscopy for the study of microorganisms.

A simultaneous application of negative phase contrast and polarization microscopy was used to study the internal structure of microbial cells. Negative phase contrast allowed us to display the fine cell structures with a refractive index of light approaching that of the environment, e.g., the cytoplasm, and converted an invisible phase image to a visible amplitude one. In the polarizing microscope, cross-polarizing filters, together with first-order quartz compensator and a turntable, showed maximum birefringence of individual structures. Material containing algae was collected in ponds in the villages Sýkořice and Zbečno (Protected Landscape Area Křivoklátsko). Objects were studied in a laboratory microscope (Carl Zeiss Jena, type NfpK), equipped with a basic body In Ph 160 with an exchangeable module Ph, LOMO St. Petersburg turntable mounted on a centering holder of our own construction and a Nikon D 70 digital SLR camera. Anisotropic granules were found only in the members of two orders of algae (Euglenales, Euglenophyceae and Chlorococcales, Chlorophyceae). They always showed strong birefringence and differed in both number and size. An important finding concerned thin pellicles in genus Euglena (Euglenales, Euglenophyceae) which exhibited weak birefringence. In genus Pediastrum (Chlorococcales, Chlorophyceae), these granules were found only in living coenobium cells. In contrast, dead coenobium cells contained many granules without birefringence-an important finding. Another important finding included birefringent lamellar structure of the transverse cell wall and weak birefringence of pyrenoids in filamentous algae of genus Spirogyra (Zygnematales, Conjugatophyceae). It was clearly displayed by the negative phase contrast and has not been documented by other methods. This method can also record the very weak birefringence of the frustule of a diatom of genus Pinnularia (Naviculales, Bacillariophyceae), which was further reinforced by the use of quartz compensator-an important finding. Simultaneous use of negative phase contrast and polarization microscopy allowed us to study not only birefringent granules of storage substances in microorganisms, but also the individual lamellae of the cell walls of filamentous algae and very thin frustule walls in diatoms. These can be visualized only by this contrast method, which provides a higher resolution (subjective opinion only) than other methods such as positive phase contrast or relief contrast.

Fluorescence nanoscopy in cell biology.

Fluorescence nanoscopy uniquely combines minimally invasive optical access to the internal nanoscale structure and dynamics of cells and tissues with molecular detection specificity. While the basic physical principles of 'super-resolution' imaging were discovered in the 1990s, with initial experimental demonstrations following in 2000, the broad application of super-resolution imaging to address cell-biological questions has only more recently emerged. Nanoscopy approaches have begun to facilitate discoveries in cell biology and to add new knowledge. One current direction for method improvement is the ambition to quantitatively account for each molecule under investigation and assess true molecular colocalization patterns via multi-colour analyses. In pursuing this goal, the labelling of individual molecules to enable their visualization has emerged as a central challenge. Extending nanoscale imaging into (sliced) tissue and whole-animal contexts is a further goal. In this Review we describe the successes to date and discuss current obstacles and possibilities for further development.

How do toxic metals affect harmful cyanobacteria? An integrative study with a toxigenic strain of Microcystis aeruginosa exposed to nickel stress

Nickel (Ni) is an essential metal for some organisms, but also a common toxic pollutant released into the water. Toxicity of Ni has not been completely established for cyanobacteria; for this reason, we evaluated the effect of sub-inhibitory Ni concentrations on a toxigenic strain of Microcystis aeruginosa and on microcystins production. Population growth, photosynthetic pigments concentration, biomarkers, including antioxidant enzymes (catalase [CAT], glutathione peroxidase [GPx], and superoxide dismutase [SOD]), as well as macromolecules (proteins, carbohydrates and lipids) were quantified; SEM and TEM observations were also performed. Population growth was affected starting at 3µgL−1, and at 24µgL−1 growth was completely inhibited; the 96-h Ni2+ IC50 was 3.7µgL−1. Ni exposure increased pigments concentration, augmented all the macromolecules, and increased activities of CAT and GPx; alterations on the internal cell structure were also observed. The integrated biomarker response revealed that Ni2+ augmented the antioxidant response and the macromolecules content. Ni stress also increased microcystins production. M. aeruginosa was affected by Ni at very low concentrations, even lower than those established as safe limit to protect aquatic biota. Aside from the toxic effects produced in this cyanobacterium, stimulation to produce toxins could potentiate the environmental risks associated with water pollution and eutrophication.

An emended description and phylogeny of the little-known Prorocentrum sipadanense Mohammad-Noor, Daugbjerg & Moestrup (Prorocentrales, Dinophyceae) from the Indian Ocean, Oman

A small Prorocentrum species was found during a pilot taxonomic survey of marine benthic dinoflagellates in the northwestern Arabian Sea, Oman. Based on the study of cells from natural samples and laboratory cultures using light and scanning electron microscopy, this taxon is attributed to the little-known Prorocentrum sipadanense, recorded so far only from East Malaysia. The description of this species has been emended to include details of internal cell structure, composition of its periflagellar area and intraspecific variability in size, shape and pore pattern. Round to oval or ovoid cells of P. sipadanese are surrounded by a prominent marginal ridge and are 17.9–23.9 µm long and 15.0–19.8 µm wide, with a foveate to reticulate thecal plate surface and asymmetric and scarce pore pattern. The small, V-shaped periflagellar area is composed of nine platelets. Cells possess two golden-brown chloroplasts with a central starch-sheathed pyrenoid and small posterior nucleus. In addition, the phylogenetic position of this taxon in Prorocentrum was revealed for the first time based on SSU and LSU rDNA data. The presence of P. sipadanense among epiphytic dinoflagellates from the Omani coast constitutes its first report from the Indian Ocean.

Comprehensive Identification and Bread-Making Quality Evaluation of Common Wheat Somatic Variation Line AS208 on Glutenin Composition.

High molecular weight glutenin subunits (HMW-GSs) are important seed storage proteins in wheat (Triticum aestivum) that determine wheat dough elasticity and processing quality. Clarification of the defined effectiveness of HMW-GSs is very important to breeding efforts aimed at improving wheat quality. To date, there have no report on the expression silencing and quality effects of 1Bx20 and 1By20 at the Glu-B1 locus in wheat. A wheat somatic variation line, AS208, in which both 1Bx20 and 1By20 at Glu-B1 locus were silenced, was developed recently in our laboratory. Evaluation of agronomic traits and seed storage proteins by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and reversed-phase high performance liquid chromatography (RP-HPLC) indicated that AS208 was highly similar to its parental cultivar Lunxuan987 (LX987), with the exception that the composition and expression of HMW-GSs was altered. The 1Bx20 and 1By20 in AS208 were further identified to be missing by polymerase chain reaction (PCR) and quantitative real-time RT-PCR (qRT-PCR) assays. Based on the PCR results for HMW-GS genes and their promoters in AS208 compared with LX987, 1Bx20 and 1By20 were speculated to be deleted in AS208 during in vitro culture. Quality analysis of this line with Mixograph, Farinograph, and Extensograph instruments, as well as analysis of bread-making quality traits, demonstrated that the lack of the genes encoding 1Bx20 and 1By20 caused various negative effects on dough processing and bread-making quality traits, including falling number, dough stability time, mixing tolerance index, crude protein values, wet gluten content, bread size, and internal cell structure. AS208 can potentially be used in the functional dissection of other HMW-GSs as a plant material with desirable genetic background, and in biscuit making industry as a high-quality weak gluten wheat source.

Polymer physics of intracellular phase transitions

Intracellular organelles are either membrane-bound vesicles or membrane-less compartments that are made up of proteins and RNA. These organelles play key biological roles, by compartmentalizing the cell to enable spatiotemporal control of biological reactions. Recent studies suggest that membrane-less intracellular compartments are multicomponent viscous liquid droplets that form via phase separation. Proteins that have an intrinsic tendency for being conformationally heterogeneous seem to be the main drivers of liquid–liquid phase separation in the cell. These findings highlight the relevance of classical concepts from the physics of polymeric phase transitions for understanding the assembly of intracellular membrane-less compartments. However, applying these concepts is challenging, given the heteropolymeric nature of protein sequences, the complex intracellular environment, and non-equilibrium features intrinsic to cells. This provides new opportunities for adapting established theories and for the emergence of new physics. The internal structure of cells is organized into compartments, many of which lack a confining membrane and instead resemble viscous liquid droplets. Evidence is mounting that these compartments form via spontaneous phase transitions. The internal structure of cells is organized into compartments, many of which lack a confining membrane and instead resemble viscous liquid droplets. Evidence is mounting that these compartments form via spontaneous phase transitions.

Inactivation of Vibrio parahaemolyticus by antimicrobial photodynamic technology using methylene blue.

Vibrio parahaemolyticus is the leading causative pathogen of gastroenteritis often related to contaminated seafood. Photodynamic inactivation has been recently proposed as a strategy for killing cells and viruses. The objective of this study was to verify the bactericidal effects caused by photodynamic inactivation using methylene blue (MB) over V. parahaemolyticus via flow cytometry, agarose gel electrophoresis and sodium dodecyl sulfate polyacrylamide gel electrophoresis. Vibrio parahaemolyticus counts were determined using the most probable number method. A scanning electron microscope and a transmission electron microscope were employed to intuitively analyze internal and external cell structure. Combination of MB and laser treatment significantly inhibited the growth of V. parahaemolyticus. The inactivation rate of V. parahaemolyticus was >99.99% and its counts were reduced by 5 log10 in the presence of 0.05 mg mL(-1) MB when illuminated with visible light (power density 200 mW cm(-2)) for 25 min. All inactivated cells showed morphological changes, leakage of cytoplasm and degradation of protein and DNA. Results from this study indicated that photodynamic technology using MB produced significant inactivation of V. parahaemolyticus mainly brought about by the degradation of protein and DNA.

Integrated Multiscale Multiphysics Modeling of Dynamic Short Circuit Behavior in Large Lithium-Ion Batteries

Scale-up of the battery raises the complexity of interactions among the physicochemical processes occurring in intricate geometries across wide range time and length scales. The entangled interplays critically affect the performance, safety, and reliability of the batteries. Violent incidents reported for lithium-ion batteries (LIBs) and consequent safety concerns are still the major hindrance for fast market penetration of LIB-powered electric drive vehicles. Most of safety incidents leading to a thermal runaway in lithium-ion batteries involve internal-short-circuit (ISC). ISCs are caused either from a latent defect growing over time or from a sudden mechanical failure of internal cell structure that may occur during battery intrusion or crush. Puncture and crush response of a battery involves various aspects of physics. The Multiscale Multidomain (MSMD) model framework provides a modular architecture, facilitating flexible integration of multiphysics model components. At initial stage of an ISC, the faulted battery is electrochemically active. This is true even through a whole event if no severe consequence follows. As such, the electrochemical model is imperative to determine the battery dynamic response to short circuit. For an induced ISC, fault current and accompanied heat must be quantified properly in consideration of thermodynamic and kinetic factors, while capturing the electronic current pathways along the intricate LIB geometries. LIB component materials become thermally unstable under exposure to high temperatures. The abuse reaction kinetics model predicts the battery’s chemical responses. In this paper, we introduce an integrated multiphysics LIB safety response model built on the MSMD nonlinear multiscale multiphysics model framework, and apply the model to investigate electrical, thermal, chemical and electrochemical behaviors of large-format cells in various form factors while resolving dynamic evolution of internal short circuit.

Fabrication and Photovoltaic Properties of Dye-Sensitized Solar Cells Modified by Graphene Oxide and Magnetic Bead

In this letter, graphene oxide (GO) and magnetic bead (MB) were incorporated into titanium dioxide (TiO2) photoelectrode by electrophoretic deposition and spin coating. The structure of TiO2 photoelectrode was fabricated into a double-layer structure and the effects of GO and MB on the internal structure of dye-sensitized solar cells (DSSCs) were investigated. This letter indicated that GO and MB could enhance the photovoltaic performances of DSSC, which made the photovoltaic conversion efficiency ( $\eta $ ) of DSSC achieve 4.63%. This improvement could be attributed to the high conductivity of GO and good dispersion of MB.