Comparison of Aerobic Scope for Metabolic Activity in Aquatic Ectotherms With Temperature Related Metabolic Stimulation: A Novel Approach for Aerobic Power Budget

ABSTRACT Interactions among microorganisms and their mineralogical substrates govern the structure, function and emergent properties of microbial communities. These interactions are predicated on spatial relationships, which dictate metabolite exchange and access to key substrates. To quantitatively assess links between spatial relationships and metabolic activity, this study presents a novel approach to map all organisms, the metabolically active subset and associated mineral grains, all while maintaining spatial integrity of an environmental microbiome. We applied this method at an outgassing fumarole of Vanuatu's Marum Crater, one of the largest point sources of several environmentally relevant gaseous compounds, including H2O, CO2 and SO2. With increasing distance from the sediment-air surface and from mineral grain outer boundaries, organism abundance decreased but the proportion of metabolically active organisms often increased. These protected niches may provide more stable conditions that promote consistent metabolic activity of a streamlined community. Conversely, exterior surfaces accumulate more organisms that may cover a wider range of preferred conditions, implying that only a subset of the community will be active under any particular environmental regime. More broadly, the approach presented here allows investigators to see microbial communities ‘as they really are’ and explore determinants of metabolic activity across a range of microbiomes.

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Procalcitonin Impairs Liver Cell Viability and Function In Vitro: A Potential New Mechanism of Liver Dysfunction and Failure during Sepsis?

BioMed Research International ◽

10.1155/2017/6130725 ◽

2017 ◽

Vol 2017 ◽

pp. 1-7 ◽

Cited By ~ 7

Author(s):

Martin Sauer ◽

Sandra Doß ◽

Johannes Ehler ◽

Thomas Mencke ◽

Nana-Maria Wagner

Keyword(s):

Metabolic Activity ◽

Liver Cell ◽

Liver Dysfunction ◽

Cell Function ◽

Positive Control ◽

Novel Approach ◽

Biosensor System ◽

Cellular Integrity ◽

And Function

Purpose. Liver dysfunction and failure are severe complications of sepsis and result in poor outcome and increased mortality. The underlying pathologic mechanisms of hepatocyte dysfunction and necrosis during sepsis are only incompletely understood. Here, we investigated whether procalcitonin, a biomarker of sepsis, modulates liver cell function and viability.Materials and Methods. Employing a previously characterized and patented biosensor system evaluating hepatocyte toxicity in vitro, human hepatocellular carcinoma cells (HepG2/C3A) were exposed to 0.01–50 ng/mL procalcitonin for2×72 h and evaluated for proliferation, necrosis, metabolic activity, cellular integrity, microalbumin synthesis, and detoxification capacity. Acetaminophen served as positive control. For further standardization, procalcitonin effects were confirmed in a cellular toxicology assay panel employing L929 fibroblasts. Data were analyzed using ANOVA/Tukey’s test.Results. Already at concentrations as low as 0.25 ng/mL, procalcitonin induced HepG2/C3A necrosis (P<0.05) and reduced metabolic activity, cellular integrity, synthesis, and detoxification capacity (allP<0.001). Comparable effects were obtained employing L929 fibroblasts.Conclusion. We provide evidence for procalcitonin to directly impair function and viability of human hepatocytes and exert general cytotoxicity in vitro.Therapeutical targeting of procalcitonin could thus display a novel approach to reduce incidence of liver dysfunction and failure during sepsis and lower morbidity and mortality of septic patients.

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Linking Microbial Phylogeny to Metabolic Activity at the Single-Cell Level by Using Enhanced Element Labeling-Catalyzed Reporter Deposition Fluorescence In Situ Hybridization (EL-FISH) and NanoSIMS

Applied and Environmental Microbiology ◽

10.1128/aem.00191-08 ◽

2008 ◽

Vol 74 (10) ◽

pp. 3143-3150 ◽

Cited By ~ 171

Author(s):

Sebastian Behrens ◽

Tina Lösekann ◽

Jennifer Pett-Ridge ◽

Peter K. Weber ◽

Wing-On Ng ◽

...

Keyword(s):

In Situ Hybridization ◽

Fluorescence In Situ Hybridization ◽

Metabolic Activity ◽

Secondary Ion Mass Spectrometry ◽

Single Cells ◽

Target Cells ◽

Filamentous Cyanobacterium ◽

Novel Approach ◽

Catalyzed Reporter Deposition

ABSTRACT To examine phylogenetic identity and metabolic activity of individual cells in complex microbial communities, we developed a method which combines rRNA-based in situ hybridization with stable isotope imaging based on nanometer-scale secondary-ion mass spectrometry (NanoSIMS). Fluorine or bromine atoms were introduced into cells via 16S rRNA-targeted probes, which enabled phylogenetic identification of individual cells by NanoSIMS imaging. To overcome the natural fluorine and bromine backgrounds, we modified the current catalyzed reporter deposition fluorescence in situ hybridization (FISH) technique by using halogen-containing fluorescently labeled tyramides as substrates for the enzymatic tyramide deposition. Thereby, we obtained an enhanced element labeling of microbial cells by FISH (EL-FISH). The relative cellular abundance of fluorine or bromine after EL-FISH exceeded natural background concentrations by up to 180-fold and allowed us to distinguish target from non-target cells in NanoSIMS fluorine or bromine images. The method was optimized on single cells of axenic Escherichia coli and Vibrio cholerae cultures. EL-FISH/NanoSIMS was then applied to study interrelationships in a dual-species consortium consisting of a filamentous cyanobacterium and a heterotrophic alphaproteobacterium. We also evaluated the method on complex microbial aggregates obtained from human oral biofilms. In both samples, we found evidence for metabolic interactions by visualizing the fate of substrates labeled with 13C-carbon and 15N-nitrogen, while individual cells were identified simultaneously by halogen labeling via EL-FISH. Our novel approach will facilitate further studies of the ecophysiology of known and uncultured microorganisms in complex environments and communities.

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Ultrastructure and Drug Metabolism in the Developing Guinea Pig

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100073131 ◽

1973 ◽

Vol 31 ◽

pp. 538-539

Author(s):

W. Kuenzig ◽

M. Boublik ◽

J.J. Kamm ◽

J.J. Burns

Keyword(s):

Guinea Pig ◽

Metabolic Activity ◽

Animal Species ◽

Adult Animal ◽

Smooth Endoplasmic Reticulum ◽

Fetal Life ◽

Mixed Function Oxidase ◽

Cytochrome P 450 ◽

Microsomal Mixed Function Oxidase ◽

Mixed Function Oxidase Activity

Unlike a variety of other animal species, such as the rabbit, mouse or rat, the guinea pig has a relatively long gestation period and is a more fully developed animal at birth. Kuenzig et al. reported that drug metabolic activity which increases very slowly during fetal life, increases rapidly after birth. Hepatocytes of a 3-day old neonate metabolize drugs and reduce cytochrome P-450 at a rate comparable to that observed in the adult animal. Moreover the administration of drugs like phenobarbital to pregnant guinea pigs increases the microsomal mixed function oxidase activity already in the fetus.Drug metabolic activity is, generally, localized within the smooth endoplasmic reticulum (SER) of the hepatocyte.

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Fibroblasts During Hypertrophic Scar Formation and Resolution

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100072587 ◽

1973 ◽

Vol 31 ◽

pp. 428-429

Author(s):

C. W. Kischer

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Cell Proliferation ◽

Fine Structure ◽

Metabolic Activity ◽

Hypertrophic Scar ◽

Normal Skin ◽

Ground Substance ◽

Hypertrophic Scars ◽

Scanning Electron

The morphology of the fibroblasts changes markedly as the healing period from burn wounds progresses, through development of the hypertrophic scar, to resolution of the scar by a self-limiting process of maturation or therapeutic resolution. In addition, hypertrophic scars contain an increased cell proliferation largely made up of fibroblasts. This tremendous population of fibroblasts seems congruous with the abundance of collagen and ground substance. The fine structure of these cells should reflect some aspects of the metabolic activity necessary for production of the scar, and might presage the stage of maturation.A comparison of the fine structure of the fibroblasts from normal skin, different scar types, and granulation tissue has been made by transmission (TEM) and scanning electron microscopy (SEM).

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Ultrastructural aspects of gymnosperms reproductive organs tissues due to their functional condition

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100083060 ◽

1978 ◽

Vol 36 (2) ◽

pp. 440-441

Author(s):

G. M. Kozubov

Keyword(s):

Metabolic Activity ◽

Functional Condition ◽

Reproductive Organs ◽

Considerable Change ◽

Complicated Structure ◽

Tetrad Stage ◽

Ubisch Bodies ◽

Similar Organization ◽

Female Reproductive Organs ◽

High Metabolic Activity

The ultrastructure of reproductive organs of pine, spruce, larch and ginkgo was investigated. It was found that the male reproductive organs possess similar organization. The most considerable change in the ultrastructure of the microsporocytes occur in meiosis. Sporoderm is being laid at the late tetrad stage. The cells of the male gameto-phyte are distinguished according to the metabolic activity of the or- ganells. They are most weakly developed in the spermiogenic cell. Ta-petum of the gymnosperms is of the periplasmodic - secretorial type. The Ubisch bodies which possess similar structure in the types investigated but are specific in details in different species are produced in tapetum.Parietal and subepidermal layers are distinguished for their high metabolic activity and are capable of the autonomous photosynthesis. Female reproductive organs differ more greatly in their struture and have the most complicated structure in primitive groups. On the first stages of their formation the inner cells of nucellus are transformed into the nucellar tapetum in which the structures similar to the Ubisch bodies taking part in the formation of the sporoderm of female gametophyte have been found.

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Copper-dependent ATP7B up-regulation drives the resistance of TMEM16A-overexpressing head-and-neck cancer models to platinum toxicity

Biochemical Journal ◽

10.1042/bcj20190591 ◽

2019 ◽

Vol 476 (24) ◽

pp. 3705-3719 ◽

Cited By ~ 2

Author(s):

Avani Vyas ◽

Umamaheswar Duvvuri ◽

Kirill Kiselyov

Keyword(s):

Oxidative Stress ◽

Head And Neck ◽

Transcriptional Activation ◽

Platinum Resistance ◽

Mrna Levels ◽

Strong Positive Correlation ◽

Platinum Compounds ◽

Copper Chelation ◽

Novel Approach ◽

Cancer Models

Platinum-containing drugs such as cisplatin and carboplatin are routinely used for the treatment of many solid tumors including squamous cell carcinoma of the head and neck (SCCHN). However, SCCHN resistance to platinum compounds is well documented. The resistance to platinum has been linked to the activity of divalent transporter ATP7B, which pumps platinum from the cytoplasm into lysosomes, decreasing its concentration in the cytoplasm. Several cancer models show increased expression of ATP7B; however, the reason for such an increase is not known. Here we show a strong positive correlation between mRNA levels of TMEM16A and ATP7B in human SCCHN tumors. TMEM16A overexpression and depletion in SCCHN cell lines caused parallel changes in the ATP7B mRNA levels. The ATP7B increase in TMEM16A-overexpressing cells was reversed by suppression of NADPH oxidase 2 (NOX2), by the antioxidant N-Acetyl-Cysteine (NAC) and by copper chelation using cuprizone and bathocuproine sulphonate (BCS). Pretreatment with either chelator significantly increased cisplatin's sensitivity, particularly in the context of TMEM16A overexpression. We propose that increased oxidative stress in TMEM16A-overexpressing cells liberates the chelated copper in the cytoplasm, leading to the transcriptional activation of ATP7B expression. This, in turn, decreases the efficacy of platinum compounds by promoting their vesicular sequestration. We think that such a new explanation of the mechanism of SCCHN tumors’ platinum resistance identifies novel approach to treating these tumors.

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Collecting Words: A Clinical Example of a Morphology-Focused Orthographic Intervention

Language Speech and Hearing Services in Schools ◽

10.1044/2020_lshss-19-00050 ◽

2020 ◽

Vol 51 (3) ◽

pp. 544-560 ◽

Cited By ~ 3

Author(s):

Kimberly A. Murphy ◽

Emily A. Diehm

Keyword(s):

Written Language ◽

Morphological Knowledge ◽

English Orthography ◽

Word Level ◽

Novel Approach ◽

Language Pathology ◽

The One ◽

Critical Intervention ◽

Reading And Spelling ◽

Reading And Spelling Difficulties

Purpose Morphological interventions promote gains in morphological knowledge and in other oral and written language skills (e.g., phonological awareness, vocabulary, reading, and spelling), yet we have a limited understanding of critical intervention features. In this clinical focus article, we describe a relatively novel approach to teaching morphology that considers its role as the key organizing principle of English orthography. We also present a clinical example of such an intervention delivered during a summer camp at a university speech and hearing clinic. Method Graduate speech-language pathology students provided a 6-week morphology-focused orthographic intervention to children in first through fourth grade ( n = 10) who demonstrated word-level reading and spelling difficulties. The intervention focused children's attention on morphological families, teaching how morphology is interrelated with phonology and etymology in English orthography. Results Comparing pre- and posttest scores, children demonstrated improvement in reading and/or spelling abilities, with the largest gains observed in spelling affixes within polymorphemic words. Children and their caregivers reacted positively to the intervention. Therefore, data from the camp offer preliminary support for teaching morphology within the context of written words, and the intervention appears to be a feasible approach for simultaneously increasing morphological knowledge, reading, and spelling. Conclusion Children with word-level reading and spelling difficulties may benefit from a morphology-focused orthographic intervention, such as the one described here. Research on the approach is warranted, and clinicians are encouraged to explore its possible effectiveness in their practice. Supplemental Material https://doi.org/10.23641/asha.12290687

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