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Ernst Brücke's 1861 essay Die Elementarorganismen has often been cited as a watershed in the history of physiology as well as in the history of cell theory. In its time it was widely read as a reform of animal cell theory, shifting the concept of the cell away from Schleiden and Schwann's original cell schema of a membranous vesicle with a nucleus, and towards the protoplasm theory that had developed in botany, centered on the cell's living contents. It was also notorious for its arguments against the necessity of both the nucleus and the cell membrane. An English translation of "The Elementary Organisms" is presented for the first time in this journal issue, with annotations and illustrations, https://doi.org/10.1007/s10739-024-09773-9. Brücke's essay was not only an intervention into cell theory: historians can read it as a continuation of debates on the nature of the organism and theories of organization, and as an epistemological meditation on the microscope. In addition, although Brücke was known as a founder of the Berlin school of organic physics, "The Elementary Organisms" shows how he combined an avant-garde physicalist physiology with a much older tradition of comparative anatomy and physiology. The following introductory essay will provide a scientific biography of Ernst Brücke up to 1863, with background on debates on biological organization, cell theory, and muscle histology. [ABSTRACT FROM AUTHOR]

The aim of this paper is to elucidate the vital meaning and strategic role that nutrition holds in Claude Bernard's "biological philosophy", in the sense Auguste Comte gave to this expression, i.e. the theoretical part of biology. I propose that Bernard's nutritive perspective on life should be thought of as an "interfield" object, following Holmes' category. Not only does nutrition bridge disciplines like physiology and organic chemistry, as well as levels of inquiry ranging from special physiology to the organism's total level, including the cell and protoplasm, but it also forms the genetic and structural foundation for Bernard's two fundamental axioms in general physiology: the necessary complementarity of destruction and creation (1) and the uniformity of this physiological law across all life forms, be it plants or animals (2). Because Bernard's nutritive theory is a major pivot for the re-ordering of life and its characterization, I argue that it must be located and understood in the scientific and metaphysical context of his time, of which he claims to be the heir and challenger—what I propose to characterize as the "epistemic space" of nutrition, on the background of which Bernard builds his own "logic". I then set out this logic of nutrition, focusing on three interrelated bernardian theses: the establishment of the theory of indirect nutrition as the basis for the notion of "milieu intérieur"; the enduring conception of nutrition as a continuous generation; the emphasis on nutrition as a way of reshaping the form/matter relationship. [ABSTRACT FROM AUTHOR]

The seta and stem in Leucodon canariensis are examined by means of light microscopy, transmission and scanning electron microscopy. Their anatomies reveal relevant differences although both show a remarkable structural complexity, as their conducting tissues are equally effective in carrying out essential processes. Five types of cells have been recognized in the transverse sections: in both seta and stem: (i) stereids in the external region with a peripheral cuticle; in the stem only: (ii) parenchymatous cells with plasmodesmata underlying the stereids; in the seta only: (iii) an unusual area of nacreous-walled cells without live protoplasm, surrounding (iv) the food-conducting cells (leptoid-like), and again both in seta and stem: (v) hydroids in the internal region. The seta in this species has a peculiar organization and shares some characteristics with polytrichaceous mosses; the ultrastructural similarities and differences and functional significance of these cells are discussed, both systematically and in relation to the habit of the moss itself. [ABSTRACT FROM AUTHOR]

Biofilms are ubiquitous at interfaces of natural and technical origin. Depending on type and application, biofilm formation is desired or has to be prevented. Therefore, reliable detection of initial biofilm growth is essential in many areas. One method of biofilm monitoring is the electrochemical impedance spectroscopy. Among other factors, this method is heavily dependent on the electrode geometry. In order to achieve a high measurement sensitivity, the electrode size must be chosen according to the biofilm that is to be measured. This paper presents an approach for simulating and modeling the optimal electrode geometry for a specific biofilm. First, a geometric model of a biofilm with up to 6000 individual bacteria is generated. The simulated impedances are used to calculate which electrode geometry maximizes sensitivity depending on the biofilm height. In the chosen example of an E. coli biofilm in a nutrient solution, the optimum size of an interdigital electrode (bar gap equals width) was 2.5 µm for a biofilm height of up to 2 µm. The used algorithms and models can be simply adapted for other biofilms. In this way, the most sensitive electrode geometry for a specific biofilm measurement can be determined with minimal effort. [ABSTRACT FROM AUTHOR]

The article discusses the concept of missing links in evolutionary transitions and explores two specific examples: the transition of algae to terrestrial habitats and the development of the chorda in vertebrates. The study on Trentepohlia, a genus of green algae, examines how these organisms are able to survive in harsh terrestrial environments through physiological adaptations. The investigation of intermediate filament proteins in Branchiostoma, a model for chordate evolution, reveals the role of a deletion in the coiled domain in enabling the expansion of cytoplasmic intermediate filaments and the development of the chorda. The article emphasizes that transitions in evolution are often complex and involve combinations of old and new traits, and that de-regulation of certain processes can lead to innovative adaptations. [Extracted from the article]

Myxogastrea is a group of eukaryotic microorganisms included in Amoebozoa. Its life cycle includes two trophic stages: plasmodia and myxamoeflagellates. However, only about 102 species have their complete life cycle known in literature and only about 18 species have their plasmodial axenic culture accomplished in laboratory conditions. The research presented herein involved culturing of Physarum galbeum on the water agar medium. The events that transpired during its life cycle including spore germination, plasmodia formation, and sporocarp development were documented especially the subglobose or discoid sporotheca and the stalk formation. The spores germinated by the V‐shape split method to release a single protoplasm. Yellow‐green pigmented phaneroplasmodia developed into sporocarps by subhypothallic type. The present article gives details of the sporocarp development of P. galbeum and its plasmodial axenic culture on solid and liquid mediums. [ABSTRACT FROM AUTHOR]

Biomolecular condensates play a key role in organizing cellular reactions by concentrating a specific set of biomolecules. However, whether condensate formation is accompanied by an increase in the total mass concentration within condensates or by the demixing of already highly crowded intracellular components remains elusive. Here, using refractive index imaging, we quantify the mass density of several condensates, including nucleoli, heterochromatin, nuclear speckles, and stress granules. Surprisingly, the latter two condensates exhibit low densities with a total mass concentration similar to the surrounding cyto- or nucleoplasm. Low-density condensates display higher permeability to cellular protein probes. We find that RNA tunes the biomolecular density of condensates. Moreover, intracellular structures such as mitochondria heavily influence the way phase separation proceeds, impacting the localization, morphology, and growth of condensates. These findings favor a model where segregative phase separation driven by non-associative or repulsive molecular interactions together with RNA-mediated selective association of specific components can give rise to low-density condensates in the crowded cellular environment. The cell interior is organized by diverse membrane-less condensates. Here, the authors reveal that the densities of certain condensates are surprisingly low, similar to the surrounding protoplasm and driven by cellular RNA as well as the crowded milieu. [ABSTRACT FROM AUTHOR]

Copyright of Food & Machinery is the property of Food & Machinery Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This essay traces an imaginative history of protoplasm in the late nineteenth and early twentieth centuries. It is a material that still exists today, though, with the advent of DNA and cellular biology, in a somewhat different form. For the biologist Ernst Haeckel (1834–1919) and the short story writer H. P. Lovecraft (1890–1937), protoplasm was the key to the specific nature of evolved life. Not only was it the material that, in the living organism, was given shape, but it was also the place where the hereditary information of what shape to give was passed on from one generation to the next, making evolution possible in the first place. For Haeckel, it was the missing piece in the puzzle that Darwin had almost completed, and with it the whole mystery and wonder of life was within explanatory reach. For Lovecraft, on the other hand, it was the very essence of the shapeless, primitive, and fundamentally menacing quality of life that civilization had to keep at bay. Though protoplasm plays a very different role in modern science than it did then, its imaginative legacy lives on in a whole range of fiction genres nowadays, and Haeckel's and Lovecraft's both very different and very similar conceptions provide a starting point for exploring a conception of biological life that is far from dead. [ABSTRACT FROM AUTHOR]

Stoichiometry of leaf macronutrients can provide insight into the tradeoffs between leaf structural and metabolic investments. Structural carbon (C) in cell walls is contained in lignin and polysaccharides (cellulose, hemicellulose, and pectins). Much of leaf calcium (Ca) and a fraction of magnesium (Mg) were further bounded with cell wall pectins. The macronutrients phosphorus (P), potassium (K), and nitrogen (N) are primarily involved in cell metabolic functions. There is limited information on the functional interrelations among leaf C and macronutrients, and the functional dimensions characterizing the leaf structural and metabolic tradeoffs are not widely appreciated. We investigated the relationships between leaf C and macronutrient (N, P, K, Ca, Mg) concentrations in two widespread broad-leaved deciduous woody species Quercus wutaishanica (90 individuals) and Betula platyphylla (47 individuals), and further tested the generality of the observed relationships in 222 woody eudicots from 15 forest ecosystems. In a subsample of 20 broad-leaved species, we also analyzed the relationships among C, Ca, lignin, and pectin concentrations in leaf cell walls. We found a significant leaf C–Ca tradeoff operating within and across species and across ecosystems. This basic relationship was explained by variations in the share of cell wall lignin and pectin investments at the cell scale. The C–Ca tradeoffs were mainly driven by soil pH and mean annual temperature and precipitation, suggesting that leaves were more economically built with less C and more Ca as soil pH increased and at lower temperature and lower precipitation. However, we did not detect consistent patterns among C–N, and C–Mg at different levels of biological organization, suggesting substantial plasticity in N and Mg distribution among cell organelles and cell protoplast and cell wall. We observed two major axes of macronutrient differentiation: the cell-wall structural axis consisting of protein-free C and Ca and the protoplasm metabolic axis consisting of P and K, underscoring the decoupling of structural and metabolic elements inherently linked with cell wall from protoplasm investment strategies. We conclude that the tradeoffs between leaf C and Ca highlight how carbon is allocated to leaf structural function and suggest that this might indicate biogeochemical niche differentiation of species. [ABSTRACT FROM AUTHOR]

Super-host plants are elegant models to evaluate the peculiarities of gall structural and nutritional profiles due to the stimuli of distinct gall inducers in temporal and spatial perspectives. Galls induced by congeneric insects, Lopesia spp. (Diptera, Cecidomyiidae) on the same host plant, Mimosa gemmulata Barneby (Fabaceae) were analyzed to estimate if variations of 1 or 2 months in gall lifespans may result in differences over the accumulation of nutritional resources, and their compartmentalization both in cell walls and protoplasm. Mimosa gemmulata hosts four Lopesia -induced galls: the lenticular bivalve-shaped gall (LG) with a 2-month life cycle, the brown lanceolate bivalve-shaped gall (BLG) and the green lanceolate bivalve-shaped gall (GLG) with 3 month-life cycles, and the globoid bivalve-shaped gall (GG) with a 4 month-life cycle. The comparisons among the four Lopesia galls, using anatomical, histometric, histochemical, and immunocytochemical tools, have demonstrated that the longest lifespan of the GG related to its highest increment in structural and nutritional traits compared with the LG, GLG, and BLG. The differences among the tissue stratification and cell wall thickness of the galls with the 2-month and the 3-month lifespans were subtle. However, the GG had thicker cell walls and higher stratification of the common storage tissue, schlerenchymatic layers and typical nutritive tissue than the other three gall morphospecies. The higher tissue thickness of the GG was followed by the formation of a bidirectional gradient of carbohydrates in the protoplasm, and the detection of xyloglucans in cell walls. Current data supported the presumption that the longest the lifespan, the highest the impact over the structural and nutritional metabolism of the Lopesia galls associated to M. gemmulata. [ABSTRACT FROM AUTHOR]

This study was conducted in the postgraduate laboratory at the College of Education for Pure Science at the University of Kerbala in collaborating with Center for Manuscript Preservation, Restoration and Care of Researchers at the Imam Hussain Holy Shrine in Kerbala for the period from 17-3-2019 to 20-9-2020 . In order to evaluate the virulence of fungal isolates Trichophyton rubrum isolate IQT-No.1 and Microsporum canis isolate IQM-No. 1 registered in the Global Genebank that accession numbers MK167434 and MK167435 respectively, in a previous study in their production of protease, lipase and keratinase during 3, 6 and 9 days incubation periods at 25°C and evaluation of the efficacy of different concentrations at twelve combinations of mineral –zinc or nano-zinc and fluconazole antifungal and the interaction between zinc in its two forms with the fluconazole antifungal on a biomass dry weight of colony (mg) on grown the liquid sabouraud dextrose broth media, as well as the phenotypic characteristics of fungal colonies developing on sabouraud dextrose agar media as a colony diameter (mm), and the microscopic features of mycelium and conidia after 14 days of incubation. The results showed that both fungi have the ability to produce the enzymes protease, lipase and keratinase, the fungus Trichophyton rubrum was higher in its production of the protease and lipase on the ninth day of incubation, which was significantly different from the Microsporum canis, while the Microsporum canis recorded a significant superiority in its production of the keratinase on the ninth day of incubation compared to the Trichophyton rubrum. The results indicated that using the combination of 30 mg zinc with 10 mg flucanazole was the best combination in the low dry weight of T. rubrum, while the M. canis was affected by the combination of 10.0mg zinc and 10.0mg flucanazole and it did not significantly differ from 15.0 mg zinc and 5.0 mg flucanazole compared with the control. The two fungi also differed with each other in the average dry weight of the biomass and the M.canis was less dry weight compared to T.rubrum. All the combinations of nano zinc and fluconazole were positive in decreasing the dry weight of the biomass of the T. rubrum, except for treatments 7.5 and 15.0 nano zinc to 22.5 and 15.5 respectively, which did not differ from the control. Likewise, the M. canis was affected by the combinations and gave a significant decrease over the control, especially in treatment, 30 nano zinc and 10 flucanozol. T.rubrum, 5.0mg mineral zinc and 5.0mg flucanozol, recorded the lowest rate of colony diameter over the solid Sabouraud’s dextrose agar medium, while two treatments 22.5m zinc with the 7.5mg fluconazol and 20mg zinc with 20mg fluconazol respectively showed the lowest average for the M.canis colony diameter (mm) and all the treatments recorded a significant decrease compared to the control. The best combination was 15.0 mg nano zinc with 5.0 mg only fluconazol in decreasing the diameter colony of T.rubrum. Likewise, the M.canis was affected by the combinations and gave a significant decrease over the control, especially in treatment 7.5mg nano zinc and 22.5mg flucanozol. The inhibition of the average diameter of the fungal culture in terms of phenotypically and grow vertically tend toward the cover plate. As for the microscopic aspect, deformation occurred in the fungal hypha, separation of protoplasm from the cell wall and aggregation of protoplasm, in addition to the disappearance of the conidia, compared to the control. In conclusion, this is the first report on T. rubrum and M.canis tinea were treated with the combination between mineral zinc or nano zinc with fluconazole antifungal to reduce the pathogenic fungal growth and deformation of conidia formation. Tests showed that nano zinc has more effective effect than mineral zinc and has an important role in reducing the amount of antifungal used. [ABSTRACT FROM AUTHOR]

Pollen viability is crucial for wheat breeding programs. The unique potential of the protoplasm of live cells to turn brown due to the synthesis of silver nanoparticles (AgNPs) through rapid photoreduction of Ag+, was exploited for testing wheat pollen viability. Ag+-viability test medium (consisting of 0.5 mM AgNO3 and 300 mM KNO3) incubated with wheat pollen turned brown within 2 min under intense light (~600 μmol photon flux density m-2s-1), but not in dark. The brown medium displayed AgNPs-specific surface plasmon resonance band in its absorption spectrum. Light microscopic studies showed the presence of uniformly stained brown protoplasm in viable pollen incubated with Ag+-viability medium in the presence of light. Investigations with transmission electron microscope coupled with energy dispersive X-ray established the presence of distinct 5–35 nm NPs composed of Ag. Powder X-ray diffraction analysis revealed that AgNPs were crystalline and biphasic composed of Ag0 and Ag2O. Conversely, non-viable pollen and heat-killed pollen did not turn brown on incubation with Ag+-medium in light. We believe that the viable wheat pollen turn brown rapidly by bio-transforming Ag+ to AgNPs through photoreduction. Our findings furnish a novel simplest and rapid method for testing wheat pollen viability. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Henan Agricultural Sciences is the property of Editorial Board of Journal of Henan Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A new species of Pythiogeton isolated from wild rice exhibiting rot and dieback of roots and stalks in California is described. Pythiogeton manoomin sp. nov. is characterized by coenocytic hyphae, club-like appressorium, and terminal or intercalary sporangia, which are often a short distance from the end of supporting hyphae. The protoplasm is discharged through a discharge tube into an elongate transient vesicle, which soon disappears, leaving the naked protoplasm to differentiate into reniform zoospores. Pythiogeton manoomin also produces thick-walled pigmented chlamydospores, not found in other Pythiogeton species. In greenhouse trials, Pg. manoomin did not infect economically important crops such as rice, bean, chard, corn, carrot, lettuce, oat, radish, sweet pepper, tomato, or wheat. Phylogenetic analysis based on ITS data supports the conclusion that this organism is a new species that is most closely related to Pg. ramosum. In this paper, we describe morphological characteristics, temperature–growth relationships, pathogenicity, and phylogenetic relationships that support the description of this taxon as a new species, Pythiogeton manoomin sp. nov. [ABSTRACT FROM AUTHOR]

Lewis Victor Heilbrunn has been called the pioneer of Ca2+ as an intracellular regulator (Campbell AK. Cell Calcium 7: 287-296, 1986; Campbell AK. Intracellular Calcium, 2015). In 1947, he was the first to provide convincing evidence that Ca2+ triggered muscle contraction (Heilbrunn LV, Wiercinski FJ. J Cell Comp Physiol 29: 15-32, 1947). Yet his work was met mostly with silence and neglect. One wonders why. Heilbrunn was a general physiologist who believed in the uniformity of nature with regard to movement. He believed that ". . . the theory of what makes cells divide should not be very different from the theory of what makes muscle contract . . ." (Heilbrunn LV. The Dynamics of Living Protoplasm, 1956). He did not believe that one could understand how the living machine worked by investigating its parts. He believed that, to understand life, one must study the dynamics of living protoplasm. The origin and evolution of Heilbrunn's thought process regarding the role of Ca2+ as a physiological activator will be traced back to the 1920s. The ways in which he tested the Ca2+ hypothesis in sea urchin eggs in the 1920s and 1930s will be explored. This work shaped Heilbrunn's thinking about the role of Ca2+ in muscle contraction. Importantly, why he and his results were ignored for years will be examined. It turned out that being right was not enough. Bad luck and a stubborn belief in an outmoded scientific philosophy contributed to the neglect. [ABSTRACT FROM AUTHOR]

Since the early nineteenth century, a membrane or wall has been central to the cell's identity as the elementary unit of life. Yet the literally and metaphorically marginal status of the cell membrane made it the site of clashes over the definition of life and the proper way to study it. In this article I show how the modern cell membrane was conceived of by analogy to the first "artificial cell," invented in 1864 by the chemist Moritz Traube (1826-1894), and reimagined by the plant physiologist Wilhelm Pfeffer (1845-1920) as a precision osmometer. Pfeffer's artificial cell osmometer became the conceptual and empirical basis for the law of dilute solutions in physical chemistry, but his use of an artificial analogue to theorize the existence of the plasma membrane as distinct from the cell wall prompted debate over whether biology ought to be more closely unified with the physical sciences, or whether it must remain independent as the science of life. By examining how the histories of plant physiology and physical chemistry intertwined through the artificial cell, I argue that modern biology relocated vitality from protoplasmic living matter to non-living chemical substances--or, in broader cultural terms, that the disenchantment of life was accompanied by the (re)enchantment of ordinary matter. [ABSTRACT FROM AUTHOR]

Cells dynamically adjust their protein translation profile to maintain homeostasis in changing environments. During nutrient stress, the kinase general control nonderepressible 2 (GCN2) phosphorylates translation initiation factor eIF2α, initiating the integrated stress response (ISR). To examine the mechanism of GCN2 activation, we have reconstituted this process in vitro, using purified components. We find that recombinant human GCN2 is potently stimulated by ribosomes and, to a lesser extent, by tRNA. Hydrogen/deuterium exchange-mass spectrometry (HDX-MS) mapped GCN2-ribosome interactions to domain II of the uL10 subunit of the ribosomal P-stalk. Using recombinant, purified P-stalk, we showed that this domain of uL10 is the principal component of binding to GCN2; however, the conserved 14-residue C-terminal tails (CTTs) in the P1 and P2 P-stalk proteins are also essential for GCN2 activation. The HisRS-like and kinase domains of GCN2 show conformational changes upon binding recombinant P-stalk complex. Given that the ribosomal P-stalk stimulates the GTPase activity of elongation factors during translation, we propose that the P-stalk could link GCN2 activation to translational stress, leading to initiation of ISR. [ABSTRACT FROM AUTHOR]

Adaptation to continuous normobaric hypoxia (CNH) protects the heart against acute ischemia/reperfusion injury. Recently, we have demonstrated the infarct size-limiting effect of CNH also in hearts of spontaneously hypertensive rats (SHR) and in conplastic SHR-mtBN strain characterized by the selective replacement of the mitochondrial genome of SHR with that of more ischemia-resistant Brown Norway rats. Importantly, cardioprotective effect of CNH was more pronounced in SHR-mtBN than in SHR. Thus, here we aimed to identify candidate genes which may contribute to this difference between the strains. Rats were adapted to CNH (FiO2 0.1) for 3 weeks or kept at room air as normoxic controls. Screening of 45 transcripts was performed in left ventricles using Biomark Chip. Significant differences between the groups were analyzed by univariate analysis (ANOVA) and the genes contributing to the differences between the strains unmasked by CNH were identified by multivariate analyses (PCA, SOM). ANOVA with Bonferroni correction revealed that transcripts differently affected by CNH in SHR and SHR-mtBN belong predominantly to lipid metabolism and antioxidant defense. PCA divided four experimental groups into two main clusters corresponding to chronically hypoxic and normoxic groups, and differences between the strains were more pronounced after CNH. Subsequently, the following 14 candidate transcripts were selected by PCA, and confirmed by SOM analyses, that can contribute to the strain differences in cardioprotective phenotype afforded by CNH: Alkaline ceramidase 2 (Acer2), Fatty acid translocase (Cd36) , Aconitase 1 (Aco1), Peroxisome proliferator activated receptor gamma (Pparg) , Hemoxygenase 2 (Hmox2) , Phospholipase A2 group IIA (Ppla2g2a), Dynamin-related protein (Drp), Protein kinase C epsilon (Pkce), Hexokinase 2 (Hk2) , Sphingomyelin synthase 2 (Sgms2) , Caspase 3 (Casp3), Mitofussin 1 (Mfn1), Phospholipase A2 group V (Pla2g5), and Catalase (Cat). Our data suggest that the stronger cardioprotective phenotype of conplastic SHR-mtBN strain afforded by CNH is associated with either preventing the drop or increasing the expression of transcripts related to energy metabolism, antioxidant response and mitochondrial dynamics. [ABSTRACT FROM AUTHOR]

Highlights • Light absorption is attenuated in dehydrated C. pumilum leaves. • Chloroplasts shrink, fragment and exhibit senescence-like features during dehydration. • Senescence is avoided by unknown mechanisms, enabling revival of the plants upon rehydration. Abstract The vegetative tissues of resurrection plants are able to withstand severe protoplasmic dehydration and revive quickly upon rehydration. Resurrection species defined as 'homoiochlorophyllous' retain most or part of their chlorophyll and photosynthetic complement in the dry state, and rely on various mechanisms to protect themselves against photo-damage. In this study, we investigated the changes in chlorophyll distribution, light absorption gradients as well as the alterations in ultrastructure that take place during dehydration of the homoiochlorophyllous species Craterostigma pumilum. Chlorophyll fluorescence profiles show that light absorption is attenuated in dry leaves, likely minimizing generation of reactive oxygen species. These are accompanied by changes that take place in the supramolecular organization of the photosynthetic protein complexes, and ordered functional adjustments of the photosynthetic apparatus, further lessening the excitation and electron pressures. Albeit these, the ultrastructural studies reveal that chloroplasts in dehydrated leaf tissues exhibit features indicative of oxidative stress, which are also reminiscent of senescing chloroplasts. These include mass proliferation of plastoglobules, variable degrees of thylakoid dismantling, as well as chloroplast fragmentation and seemingly vacuolar degradation of such fragments. In addition, unique vesicular structures between the two chloroplast envelope membranes were visualized, some of which appeared to detach from chloroplasts, likely en route to degradation. Together, the data indicate that homoiochlorophyllous resurrection species handle photo-induced damage during dehydration on two levels. Minimization of photo-damage is achieved by attenuation of light absorption and other photo-protective mechanisms. When this is insufficient and significant damage does occur, elimination of damaged components takes place via processes resembling senescence. Nevertheless, these processes are reversible, enabling the plants to avoid the terminal steps of senescence and, hence, to recover. [ABSTRACT FROM AUTHOR]

Black foot disease of grapevines causes significant economic loss to the viticulture industry worldwide. A novel method was developed to investigate the fate of propagules of three species associated with black foot disease in New Zealand, Dactylonectria macrodidyma, Ilyonectria europaea and I. liriodendri, in soil. Conidia or mycelium of one isolate each of the three species were buried in soil in nylon mesh bags, and conidia/chlamydospore numbers were determined microscopically after 2 and 3 weeks. Conidia and chlamydospores were produced by mycelial inocula of all isolates, with greater numbers of chlamydospores after 3 weeks. Conidial inocula of all isolates also produced chlamydospores. Chlamydospores were formed at either the terminus or side of a hypha, and single and multiple conidia formed chlamydospores by combining their cellular protoplasm. Chlamydospores were produced from conidia, and conidia from mycelium faster for the I. europaea isolate than the D. macrodidyma and I. liriodendri isolates. The rapid formation of chlamydospores as survival propagules will facilitate the ability of these pathogens to persist in soil in the absence of a host. [ABSTRACT FROM AUTHOR]

This article reviews G. Deleuze's (1925-1995) relationship to C.S. Peirce (1839-1914) played out in the former's lectures held and books published between 1981 and 1985, both dedicated to the signs of cinema. It focuses on the interchange of their respective concepts of (triadic) relations and habit, revealing a higher resonance from Deleuze's thought towards Peirce's pragmatism than the literature usually admits. It faces an embarrassing issue: Deleuze never mentions pragmatism in his studies on semiotic concerning the classification of the signs of cinema, to which Peirce, along with H. Bergson (1859-1941), are the main references. Reversely, when Deleuze unsystematically approaches pragmatism he makes no mention of Peirce at all. In the final part, the article provides a portrait of the early and recent reception of Peirce in France to insert the argument into the historical context. Ultimately, this article exposes and inspects eight limited, but close, conceptual correspondences between Deleuze's and Peirce's thought with respect to: triadic relations and reality; triadic relations and meaning; irreducibility of triadic relations; triadic relations and the changing form of time; habits and triadic relations; habits and human beings; habits and nature; and the principle of habit-taking. [ABSTRACT FROM AUTHOR]

This article interprets a series of aborted transcriptions of "The Raven" undertaken by Charles Sanders Peirce and named by him "Art Chirography" as a species of re-mediation of Poe's poem. Attending to Peirce's knowledge of Poe's works (real and faked), the relation between sound and inscription, the power of handwriting as media phenomenon in the nineteenth century, and Peirce's evolutionary metaphysics, the essay concludes that Peirce's "art chirography" is an attempt to image the play of chance and habit-taking that lies at the heart of both Poe's poem and Peirce's metaphysics. [ABSTRACT FROM AUTHOR]

Cystic fibrosis (CF) is the most common genetic disorder that causes a significant damage in secretory epithelial cells due to the defective ion flux across the cystic fibrosis transmembrane conductance regulator (CFTR) Cl- channel. Pancreas is one of the organs most frequently damaged by the disease leading to pancreatic insufficiency, abdominal pain and an increased risk of acute pancreatitis in CF patients causing a significant decrease in the quality of life. CFTR plays a central role in the pancreatic ductal secretory functions by carrying Cl- and HCO3- ions across the apical membrane. Therefore pathophysiological studies in CF mostly focused on the effects of impaired ion secretion by pancreatic ductal epithelial cells leading to exocrine pancreatic damage. However, several studies indicated that CFTR has a central role in the regulation of intracellular signaling processes and is now more widely considered as a signaling hub in epithelial cells. In contrast, elevated intracellular Ca2+ level was observed in the lack of functional CFTR in different cell types including airway epithelial cells. In addition, impaired CFTR expression has been correlated with damaged mitochondrial function in epithelial cells. These alterations of intracellular signaling in CF are not well characterized in the exocrine pancreas yet. Therefore in this review we would like to summarize the complex role of CFTR in the exocrine pancreas with a special focus on the intracellular signaling and mitochondrial function. [ABSTRACT FROM AUTHOR]

Fipronil (FIP), a broad-spectrum phenylpyrazole, is extensively used across the globe to control pests and as a veterinary drug. Incorrect use of FIP leads to contamination of soil and water ultimately causes toxic effects in non-target organisms. Therefore, the present experimental study was aimed to determine the deleterious effects of sub-lethal concentrations of FIP in adult cockerels. FIP mixed in corn oil was administered orally in different groups as follows: A = control, B = 1.5 mg/kg, C = 2.5 mg/kg, D = 3.5 mg/kg and E = 4.5 mg/kg body weight for 60 d. Signs of toxicity like anemic comb, tremors, gasping and watery droppings were evident in birds exposed to higher levels. The feed intake, body weight, absolute and the relative weight of different organs were significantly (p ≤ .05) decreased in birds exposed to higher concentrations. Histomorphometric analysis of small intestine in birds exposed to higher levels of FIP showed decreased villus height and crypt depth of duodenum, jejunum and ilium. Histologically, congestion in liver, pyknosis of hepatocytes and congestion in kidneys along with necrosis of tubular epithelial cells and increased urinary spaces were observed in birds. Microscopically, seminiferous tubules exhibited necrotic nuclei of the spermatids, arrest of process of spermatogenesis and admixture of necrotic cells in testes of exposed birds. Moreover, significantly (p ≤ .05) decreased hematological parameters such as erythrocytes counts, hemoglobin concentrations and hematocrit, while increased total leukocyte counts were recorded in birds. Furthermore, significantly (p ≤ .05) increased concentrations of serum urea, creatinine, alanine aminotransferase, aspartate aminotransferase and cardiac isoenzyme (CK-MB), while reduced serum testosterone levels were recorded in birds. Results revealed significantly (p ≤ .05) increased frequency of micronuclei in erythrocyte and bone marrow cells. The findings of our study demonstrated that FIP induces deleterious impacts on multiple tissues in birds even at low doses. [ABSTRACT FROM AUTHOR]

The article announces that Daniel Liu has got 2020 Everett Mendelsohn Prize for his essay, "The Cell and Protoplasm as Container, Object, and Substance, 1835–1861."

Abstract: Mammalian oocytes and zygotes have the unique ability to reprogram a somatic cell nucleus into a totipotent state. SUV39H1/2‐mediated histone H3 lysine‐9 trimethylation (H3K9me3) is a major barrier to efficient reprogramming. How SUV39H1/2 activities are regulated in early embryos and during generation of induced pluripotent stem cells (iPSCs) remains unclear. Since expression of the CRL4 E3 ubiquitin ligase in oocytes is crucial for female fertility, we analyzed putative CRL4 adaptors (DCAFs) and identified DCAF13 as a novel CRL4 adaptor that is essential for preimplantation embryonic development. Dcaf13 is expressed from eight‐cell to morula stages in both murine and human embryos, and Dcaf13 knockout in mice causes preimplantation‐stage mortality. Dcaf13 knockout embryos are arrested at the eight‐ to sixteen‐cell stage before compaction, and this arrest is accompanied by high levels of H3K9me3. Mechanistically, CRL4‐DCAF13 targets SUV39H1 for polyubiquitination and proteasomal degradation and therefore facilitates H3K9me3 removal and zygotic gene expression. Taken together, CRL4‐DCAF13‐mediated SUV39H1 degradation is an essential step for progressive genome reprogramming during preimplantation embryonic development. [ABSTRACT FROM AUTHOR]

Schizophrenia (SCZ) is a devastating mental disorder that is characterized by distortions in thinking, perception, emotion, language, sense of self, and behavior. Epidemiological evidence suggests that subtle perturbations in early neurodevelopment increase later susceptibility for disease, which typically manifests in adolescence to early adulthood. Early perturbations are thought to be significantly mediated through incompletely understood genetic risk factors. The advent of induced pluripotent stem cell (iPSC) technology allows for the in vitro analysis of disease-relevant neuronal cell types from the early stages of human brain development. Since iPSCs capture each donor's genotype, comparison between neuronal cells derived from healthy and diseased individuals can provide important insights into the molecular and cellular basis of SCZ. In this review, we discuss results from an increasing number of iPSC-based SCZ/control studies that highlight alterations in neuronal differentiation, maturation, and neurotransmission in addition to perturbed mitochondrial function and micro-RNA expression. In light of this remarkable progress, we consider also ongoing challenges from the field of iPSC-based disease modeling that call for further improvements on the generation and design of patient-specific iPSC studies to ultimately progress from basic studies on SCZ to tailored treatments. [ABSTRACT FROM AUTHOR]

Acrylamide (AA) occurs in many cooked carbohydrate-rich foods and has caused widespread concern as a possible carcinogen. Glycidamide (GA) is the ultimate genotoxic metabolite of AA. The present study was to investigate the protective effect of Cyanidin-3- O -glucoside (C3G) against AA- and GA-induced reproductive toxicity in R2C Leydig cells. The results demonstrated that C3G inhibited AA- and GA-induced cytotoxicity and mitochondria-mediated cell apoptosis, the effective doses of C3G were ranging from 10 to 50 μM. Besides, AA (1.925 mM) and GA (0.872 mM) exposure increased ROS level and decreased mitochondrial membrane potential, which led to a decrease in progesterone production, while C3G ranging from 10 to 50 μM reduced ROS immediately, and increased progesterone production after 24 h treatment. Furthermore, C3G up-regulated expression of Bcl-2 protein and down-regulated pro-apoptotic protein Bax and cleaved Caspase-3 after 24 h treatment in 1.925 mM AA- and 0.872 mM GA-treated R2C cells. Moreover, C3G intervention increased the protein expression of steroidogenic acute regulatory (StAR). It was concluded that C3G is effective in reducing AA- and GA-induced reproductive toxicity via inhibition of ROS generation, mitochondrial membrane depolarization and apoptosis, as well as activating steroidogenic enzymes. [ABSTRACT FROM AUTHOR]

A comparative study of two forms of Betula pendula Roth differing in wood structure (B. pendula var. pendula with common straight-grained wood and B. pendula var. carelica with abnormal patterned wood) has demonstrated that the level of phospholipids reflects the content of parenchyma cells in the wood and can be regarded as an indicator of the abnormality degree in the tissue structure. The content of glycolipids testifies to the dynamics of the plastid apparatus condition and correlates with the activity of the storage function in the wood parenchyma cells. It is shown that two directions in the differentiation of cambial derivatives, namely by the pathway of cell death (vessels and fibrous elements) and the preservation of a live protoplast (parenchyma cells), correlate with different fatty acid compositions of membrane lipids. In the first case, the share of saturated fatty acids in the composition of phospholipids and glycolipids increases, indicating a deterioration of the functional characteristics of cell membranes. In the latter case, the share of unsaturated, mainly dienoic fatty acids, increases, which reflects a rise in the activity of cell membranes. During periods with the highest rate of metabolism, the content of polyunsaturated, mainly trienoic fatty acids increase in membrane lipids. [ABSTRACT FROM AUTHOR]

Abstract: Fresh beef color stability is a muscle‐specific trait. Mitochondria remain biochemically active in postmortem beef muscles and influence meat color. Although several intrinsic factors governing muscle‐specific beef color have been studied extensively, the role of mitochondrial functionality in muscle‐dependent color stability is yet to be examined. Therefore, the objective of this study was to examine mitochondrial oxygen consumption rate (OCR), mitochondrial metmyoglobin reducing activity (MMRA), and instrumental color attributes in beef Longissimus lumborum (LL) and Psoas major (PM) during retail display. Using a split‐plot design, six (n = 6) beef LL and PM muscles were fabricated into 2.54‐cm‐thick steaks, packaged in polyvinylchloride overwrap, and randomly assigned to instrumental color measurement for six days and mitochondrial isolation for days 0, 1, 3, or 5 of display at 4 °C. Mitochondria isolated from steaks were used to assess the effects of muscle and display time on OCR and MMRA. The PM steaks were less color‐stable (p < 0.05) during display compared with the LL counterparts. For both muscles, OCR decreased during display, albeit the decrease was more rapid in PM than in the LL. Similarly, MMRA decreased during display for the LL and PM. However, this decrease was less (p < 0.05) for mitochondria from LL steaks, which were more resistant to display‐mediated effects on OCR and MMRA. These results indicated that the muscle‐specific differences in mitochondrial activity may contribute partially to the variations in color stability of beef LL and PM muscles. Practical Application: During retail display tenderloin steaks packaged in PVC overwrap discolor quicker than strip loin steaks. This research determines the basis for muscle‐specific differences in color stability. The results indicate that mitochondria present in tenderloin lose its functionality faster than strip loin mitochondria. Developing strategies to minimize muscle‐specific differences in mitochondrial changes can increase color stability and value of fresh beef. [ABSTRACT FROM AUTHOR]

Summary: Low testosterone levels in aging men are associated with insulin resistance. Mitochondrial dysfunction, changes in glycogen metabolism, and lipid accumulation are linked to insulin resistance in skeletal muscle. In this randomized, double‐blinded, placebo‐controlled study, we investigated the effects of six‐month testosterone replacement therapy (TRT) and strength training (ST) on mitochondrial, glycogen, and lipid droplet (LD) content in skeletal muscle of aging men with subnormal bioavailable testosterone (BioT) levels. Mitochondrial, glycogen, and LD volume fractions in muscle biopsies were estimated by transmission electron microscopy. Insulin sensitivity (insulin‐stimulated Rd) and body composition were assessed by euglycemic‐hyperinsulinemic clamp and dual X‐ray absorptiometry, respectively. TRT significantly increased total testosterone levels, BioT, and lean body mass (LBM) (p < 0.05), whereas percent body fat decreased (p < 0.05), and insulin sensitivity was unchanged. Baseline mitochondrial volume fraction correlated inversely with percent body fat (ρ = −0.43; p = 0.003). Δ‐mitochondrial fraction correlated positively with Δ‐total testosterone (ρ = 0.70; p = 0.02), and Δ‐glycogen fraction correlated inversely with Δ‐LBM (ρ = −0.83; p = 0.002) during six‐month TRT, but no significant changes were observed in mitochondrial, glycogen, and LD volume fractions during TRT and ST. In conclusion, in this exploratory small‐scale study, the beneficial effects of six‐month TRT on total testosterone, LBM, and percent body fat were not followed by significant changes in fractions of mitochondria, glycogen, or lipid in skeletal muscle of aging men with lowered testosterone levels. Six‐month ST or combined three‐month ST+TRT did not change intramyocellular mitochondria, glycogen, and LD fractions compared to placebo. However, further studies with a larger sample size are needed. [ABSTRACT FROM AUTHOR]

Protein aggregates are formed due to the inappropriate folding of polypeptides. Human lysozyme (HLZ) plays an important role in the innate immune response of the body and has been used extensively as a model protein to study aggregation. In this study, we showed that HLZ undergoes unfolding induced aggregation when heated by using spectroscopic and microscopic techniques. We further showed that the aggregates were recognized by polyclonal antibodies against the native HLZ. The consequences of these observations are further co-related with mammalian physiology. [ABSTRACT FROM AUTHOR]

Castor cake is a by-product of the extraction of oil from from seeds of castor plants ( Ricinus communis ). This by-product contains high levels of proteins, but a toxic protein, ricin, limits its use as an animal feed. Ricin can be efficiently inactivated by treatment with calcium oxide (CaO), which can be evaluated by a cytotoxicity assay using LLC - MK2 cells. The mechanism by which the CaO treatment inactivates ricin, however, is unclear. We report the structural changes responsible for ricin inactivation. Purified ricin was treated with 0.6% CaO and then analyzed by mass spectrometry. This treatment degraded the ricin at preferential sites. The aqueous CaO solution had a pH >12, which preferentially cleaved asparagine residues, followed by glutamine, serine and glycine residues. The alkaline pH affected the tertiary structure of the ricin, cleaving its polypeptide chains and thereby eliminating its cytotoxic activity. [ABSTRACT FROM AUTHOR]

Electromagnetic radiation (EMR) can induce or modulate several neurobehavioral disorders. Duration and frequency of exposure of EMR is critical to develop cognitive disorders. Even though EMR-2450 is widely used, its effects on cognition in relation to mitochondrial function and apoptosis would provide better understanding of its pathophysiological effects. Therefore, a comparative study of different frequencies of EMR exposure would give valuable information on effects of discrete frequencies of EMR on cognition. Male rats were exposed to EMR (900, 1800 and 2450 MHz) every day for 1 h for 28 consecutive days. The cognitive behavior in terms of novel arm entries in Y-maze paradigm was evaluated every week after 1 h to last EMR exposure. Animals exposed to EMR-2450 MHz exhibited significant cognitive deficits. EMR-2450 MHz caused loss of mitochondrial function and integrity, an increase in amyloid beta expression. There was release of cytochrome-c and activation of apoptotic factors such as caspase-9 and -3 in the hippocampus. Further, there was decrease in levels of acetylcholine, and increase in activity of acetyl cholinesterase, indicating impairment of cholinergic system. Therefore, exposure of EMR-2450 in rats caused cognitive deficit with related pathophysiological changes in mitochondrial and cholinergic function, and amyloidogenesis. [ABSTRACT FROM AUTHOR]

Chlorination remains a big hurdle in membrane technology as the most commonly used membranes for water purification consist of a polyamide top-layer, which is not fully resistant towards chlorine-induced oxidation. In this work, DOW FILMTEC™ BW30 membrane elements were systematically chlorinated with NaOCl at pilot-scale under acidic conditions (pH4) at 10 bar for 2.5 h. Variations in membrane performance and their physicochemical properties were determined by ATR-FTIR, XPS, WD-XRF, SEM, AFM and zeta-potential measurements. With increasing bleaching concentration, both membrane roughness and chlorine incorporation via N- and ring-chlorination increased, while surface charge remained quasi unaltered. Both water flux and salt passage decreased proportionally over the whole concentration range. Accordingly, positron annihilation lifetime spectroscopy (PALS) revealed a decrease in the size of the top-layer free-volume elements as chlorine concentration increased, confirming, for the first time in a quantitative manner, the so-called tightening effect. The obtained results also show that thin-film composite (TFC) membranes are altered differently when chlorinated under pressure than via simple immersion, as conventionally performed in literature. [ABSTRACT FROM AUTHOR]

The development of sensitive methods for imaging endogenous peroxynitrite (ONOO − ) in the mitochondria of living cells is very important to disclose its diverse physiological and pathological functions. In this paper, we have described a simple, mitochondria-targeted far-red fluorescent probe Mito-PN for selectively detecting ONOO − even though in the presence of higher concentration (1 mM) other biologically important substances. The experimental results indicated that probe Mito-PN could quantitatively determine ONOO − in the range of 0.5–8 μM with the detection limit of 17 nM. In addition, probe Mito-PN exhibits a fast response for ONOO − (<5 s), which is favorable for monitoring the highly reactive and short-lived ONOO − in the biological systems. The excellent sensing properties of probe Mito-PN enable its applications in the tracking of the fluctuations of endogenous ONOO − levels in the mitochondria of living cells. [ABSTRACT FROM AUTHOR]

Background/Aims: Podocyte injury, especially podocyte apoptosis, plays a major role in early-stage diabetic nephropathy (DN). Swiprosin-1, also known as EF hand domain containing 2 (EFhd2), is a Ca2+-binding protein in different cell types. However, the function of swiprosin-1 in podocytes remains unknown. Methods: The expression and distribution of swiprosin-1 were investigated in the mouse renal glomerulus and conditionally immortalized mouse podocyte cell line MPC-5. The expression of swiprosin-1 was also detected in streptozotocin (STZ)-treated mice and MPC-5 cells treated with high glucose (HG). Nephrin and podocin were detected by immunohistochemistry and immunofluroscence. Collagen IV, transforming growth factor-β (TGF-β) and fibronectin mRNA expressions were assayed by real-time PCR. Apoptotic proteins and phosphorylation of p38 mitogen-activated protein kinase (MAPK) were detected by immunoblotting. Results: Swiprosin-1 was found to be expressed in podocytes of the mouse glomerulus and MPC-5 cells. Swiprosin-1 expression was increased in STZ-treated mice and MPC-5 cells treated with HG. In Swiprosin-1-/- diabetic mice, kidney/ body weight, urinary albumin, podocyte foot process effacement and glomerular basement membrane thickening were attenuated; the downregulation of nephrin and podocin expression in the glomerulus was inhibited; and the upregulation of collagen IV, TGF-β and fibronectin mRNA expression in the renal cortex was ameliorated as compared with those in diabetic swiprosin-1+/+ mice. In addition, the increased apoptosis of podocytes, proapoptotic protein expression and p38 phosphorylation in Swiprosin-1-/- diabetic mice were inhibited as compared with those in diabetic swiprosin-1+/+ mice. Knockdown of swiprosin-1 in MPC-5 cells reduced the apoptosis of podocytes, proapoptotic protein expression and p38 phosphorylation induced by HG. Targeted knockdown of p38 attenuated the increased apoptosis of MPC-5 cells over-expressing swiprosin-1. Conclusion: Swiprosin-1 expression in podocytes of the mouse glomerulus played a critical role in early-stage DN. Swiprosin-1 deficiency in early DN attenuated mitochondria-dependent podocyte apoptosis induced by hyperglycemia or HG via p38 MAPK signaling pathway. [ABSTRACT FROM AUTHOR]

Background/Aims: Mitochondrial homeostasis is implicated in the development and progression of endometriosis through poorly defined mechanisms. Mst1 is the major growth suppressor related to cancer migration, apoptosis and proliferation. However, whether Mst1 is involved in endometriosis apoptosis and migration via regulating the mitochondrial function remains to be elucidated. Methods: Expression of Mst1 in endometriosis was examined via western blots. Cellular apoptosis was detected via MTT and TUNEL assay. Gain of function assay about Mst1 was conducted via adenovirus over-expression. Mitochondrial functions were evaluated via mitochondrial membrane potential JC-1 staining, ROS flow cytometry analysis, mPTP opening assessment and immunofluorescence of HtrA2/Omi. The mitophagy activity were examined via western blots and immunofluorescence. Results: First, we found that Mst1 was significantly downregulated in the ectopic endometrium of endometriosis compared to the normal endometrium. However, the recovery of Mst1 function was closely associated with the inability of endometrial stromal cells (ESCs) to migrate and survive. A functional study indicated that regaining Mst1 enhanced Drp1 post-transcriptional phosphorylation at Ser616 and repressed Parkin transcription activity via p53, leading to mitochondrial fission activation and mitophagy inhibition. Excessive Drp1-related fission forced the mitochondria to liberate HtrA2/Omi into the cytoplasm. Moreover, Mst1-induced defective mitophagy evoked cellular oxidative stress, energy metabolism and calcium overload. Through excessive mitochondrial fission and aberrant mitophagy, Mst1 launched caspase 9-related mitochondrial apoptosis and abrogated F-actin/lamellipodium-dependent cellular migration. Notably, we also defined NR4A/miR181c as the upstream signal for Mst1 dysfunction in endometriosis. Conclusion: Collectively, our results comprehensively described the important role of the NR4A-miR181c-Mst1 pathway in endometriosis, which handled mitochondrial apoptosis and F-actin/ lamellipodium-based migration via the regulation of Drp1-related mitochondrial fission and Parkin-required mitophagy, with a potential application in endometriosis therapy by limiting ESCs migration and promoting apoptosis. [ABSTRACT FROM AUTHOR]

Thecadinium kofoidiiis a marine sand-dwelling dinoflagellate that sometimes forms dense blooms. This species was previously thought to be an exclusively autotrophic dinoflagellate, and its mixotrophic ability has not been explored yet. By investigating its ecophysiology, its trophic mode should be revealed. We explored the mixotrophic ability ofT. kofoidiiby examining its protoplasm under light and transmission electron microscopes with diverse algal prey species. Furthermore, the feeding mechanism ofT. kofoidiiand prey species on which it feeds were investigated. In addition, the growth and ingestion rates ofT. kofoidiias a function of prey concentration were determined when feeding on the benthic cryptophyteRhodomonas salina.Thecadinium kofoidiiwas able to feed onR. salinaand the dinoflagellateSymbiodinium voratum, which had equivalent spherical diameters (ESDs) ≤ 10.1 µm, while it did not feed on the benthic dinoflagellatesLevanderina fissa,Prorocentrum concavumorOstreopsiscf.ovata, which had ESDs ≥ 15 µm.Thecadinium kofoidiifed on the edible prey cells using the peduncle. The maximum ingestion rate ofT. kofoidiionR. salinawas 1.3 cells predator−1d−1. However, feeding onR. salinadid not significantly increase the growth rate ofT. kofoidii. The low ingestion rate ofT. kofoidiionR. salinamay have partially resulted in the lack of significant increase in its growth rate due to mixotrophy. The present study discovered predator–prey relationships betweenT. kofoidiiandR. salinaandS. voratum, which may change our view of the energy flow and carbon cycling in marine benthic food webs. [ABSTRACT FROM PUBLISHER]

T cell functions are regulated by multiple signaling cascades, including the MKK4-JNK (c-Jun NH 2 terminal kinase) pathway. However, the mechanism regulating the MKK4-JNK axis in T cells remains unclear. Herein, we demonstrated that protein acetylation modulates JNK activity induced by T cell receptor (TCR) activation. The acetyltransferase, CREB-binding protein (CBP), is transported from the nucleus to the cytoplasm in response to TCR cross-linking. To investigate the role of CBP in TCR signaling, we overexpressed CBP in the cytoplasm of Jurkat cells, a human T lymphocyte line. Enforced expression of cytoplasmic CBP led to MKK4 acetylation and interfered with MKK4-mediated JNK phosphorylation. Insufficient JNK activity decreased the activity of the transcription factor, AP-1. In contrast, other transcription factors, NF-κB and NFAT, stimulated with anti-CD3 and anti-CD28 antibodies were activated normally in the presence of cytoplasmic-CBP. These results provide valuable insights into the role of acetylation in MKK4-JNK signaling in T cells. [ABSTRACT FROM AUTHOR]

Background/Aims: Previous studies have shown that heat shock protein 90 (HSP90)-mediated mitochondrial import of connexin 43 (Cx43) is critical in preconditioning cardioprotection. The present study was designed to test whether postconditioning has the same effect as preconditioning in promoting Cx43 translocation to mitochondria and whether mitochondrial HSP90 modulates this effect. Methods: Cellular models of hypoxic postconditioning (HPC) from rat heart-derived H9c2 cells and neonatal rat cardiomyocytes were employed. The effects of HPC on cardiomyocytes apoptosis were examined by flow cytometry and Hoechst 33342 fluorescent staining. Reactive oxidative species (ROS) production was assessed with the peroxide-sensitive fluorescent probe 2',7'-dichlorofluorescin in diacetate (DCFH-DA). The anti- and pro-apoptotic markers Bcl-2 and Bax, HSP90 and Cx43 protein levels were studied by Western blot analysis in total cell homogenate and sarcolemmal and mitochondrial fractions. The effects on HPC of the HSP90 inhibitor geldanamycin (GA), ROS scavengers superoxide dismutase (SOD) and catalase (CAT), and small interfering RNA (siRNA) targeting Cx43 and HSP90 were also investigated. Results: HPC significantly reduced hypoxia/reoxygenation (H/R)-induced cardiomyocyte apoptosis. These beneficial effects were accompanied by an increase in Bcl-2 levels and a decrease in Bax levels in both sarcolemmal and mitochondrial fractions. HPC with siRNA targeting Cx43 or the ROS scavengers SOD plus CAT significantly prevented ROS generation and HPC cardioprotection, but HPC with either SOD or CAT did not. These data strongly supported the involvement of Cx43 in HPC cardioprotection, likely via modulation of the ROS balance which plays a central role in HPC protection. Furthermore, HPC increased total and mitochondrial levels of HSP90 and the mitochondria-to-sarcolemma ratio of Cx43; blocking the function of HSP90 with the HSP90 inhibitor geldanamycin (GA) or siRNA targeting HSP90 prevented the protection of HPC and the HPC-induced association of Cx43, indicating that mitochondrial HSP90 was important for mitochondrial translocation of Cx43 during HPC. Conclusion: Mitochondrial HSP90 played a central role in HPC cardioprotection, and its activity was linked to the mitochondrial targeting of Cx43, the activation of which triggered ROS signaling and the subsequent reduction of redox stress. Consequently, its target gene, Bcl-2, was upregulated, and proapoptotic Bax was inhibited in the sarcolemma and mitochondria, ultimately attenuating H/R-induced cardiomyocyte apoptosis. These data reveal a novel mechanism of HPC protection. [ABSTRACT FROM AUTHOR]