Eyespot and other pigments in nematode esophageal muscle cells

1979 ◽  
Vol 57 (5) ◽  
pp. 1057-1069 ◽  
Author(s):  
Gwendolyn Bollerup ◽  
A. H. Burr
Keyword(s):  
Absorption Spectra ◽  
Chemical Properties ◽  
Muscle Cells ◽  
Common Species ◽  
Dense Patch ◽  
Larval Hatching ◽  
Esophageal Muscle

Nematode eyespots are recognizable as paired spots of granular, dense pigment localized within anterior muscle cells of the esophagus, or projections thereof. The 10 species studied here include a variety of morphologies and colors. A third, less dense, patch of eyespot pigment was observed in six of the species. Of the species for which eggs could be obtained, eyespots of five developed 2–5 days prior to larval hatching, but those of one, Symplocostoma sp., appeared only in males just prior to the last moult. Chemical properties and absorption spectra of eyespot pigments of the more common species were investigated. The brown eyespot pigment of Enoplus spp. resembles mature eumelanin, and the purplish pigment of two other species is probably incompletely polymerized eumelanin. Properties of less stable, reddish eyespot of four species are unlike melanins or other known pigment classes.Another granular esophageal pigment was observed in 4 of the 10 species. Unlike eyespot pigment it is distributed along the length of the esophagus and is absent at hatching, accumulating with age. That of Enoplus spp. resembles hemosiderin in chemical properties. Also, hemoglobin was identified in nonpigmented regions of the esophageal muscle and in the hypodermal chords of two species.

scholarly journals The Effects of Chromospheric Radiation on the Circumstellar Chemistry of Evolved Stars

1987 ◽  
Vol 120 ◽  
pp. 379-385
Author(s):  
A. E. Glassgold
Keyword(s):  
Mass Loss Rate ◽  
Chemical Properties ◽  
Common Species ◽  
Circumstellar Envelopes ◽  
Evolved Stars ◽  
Radiation Fields ◽  
Nearby Stars ◽  
Physical And Chemical ◽  
Gas Ratio ◽  
Small Dust

The physical and chemical properties of the circumstellar envelopes of evolved stars are strongly affected by the interstellar radiation field. Other sources of UV radiation should be similarly effective, and some examples are nearby stars (including companions), chromospheres, and the central stars of planetary nebulae. We consider the particular case of Alpha Ori, which has a chromosphere and an extended CSE with a small dust to gas ratio. Its properties are dominated by the chromospheric and interstellar radiation fields. The most common species are neutral atoms and first ions, and the electron fraction is high throughout the entire CSE, i.e. at least 10−4. The abundances of neutrals peak in the outer CSE close to where the chromospheric and interstellar radiation fields are equal. An important application is KI, whose density has been measured by scattering. The theory predicts that the slope of the KI density should change from about −1.5 to −3.5 in the outer envelope, the exact values being determined by the temperature distribution. The mass loss rate implied by the KI density is of the order of 4×10−6 M⊙ yr−1.

ISOLATION AND IDENTIFICATION OF TWO PHENAZINES FROM A STRAIN OF PSEUDOMONAS AUREOFACIENS

1965 ◽  
Vol 43 (9) ◽  
pp. 1055-1062 ◽  
Author(s):  
J. I. Toohey ◽  
C. D. Nelson ◽  
G. Krotkov
Keyword(s):  
Carboxylic Acid ◽  
Absorption Spectra ◽  
Infrared Absorption ◽  
Chemical Properties ◽  
The Other ◽  
Isolation And Identification ◽  
Pseudomonas Aureofaciens ◽  
Infrared Absorption Spectra

A method is described for the purification of two phenazine compounds from cultures of a strain of Pseudomonas aureofaciens. The chemical properties of the compounds are described and the ultraviolet, visible, and infrared absorption spectra are shown. One compound is identified as phenazine-1-carboxylic acid and the other is probably 2-hydroxyphenazine-1-carboxylic acid.

Extremely high diversity of euglenophytes in a small pond in eastern Poland

2018 ◽  
Vol 151 (1) ◽  
pp. 18-34 ◽  
Author(s):  
Małgorzata Poniewozik ◽  
Josef Juráň
Keyword(s):  
Chemical Properties ◽  
Diversity Indices ◽  
Common Species ◽  
Temperature Conductivity ◽  
Upgma Cluster Analysis ◽  
Water Ph ◽  
Special Concern ◽  
Physical And Chemical ◽  
Very High ◽  
And Chemical Properties

Background and aims – Phytoplankton samples were taken from a periodic, small and very shallow former clay-pit pond in eastern Poland near Lublin city. Diversity of the euglenophyte community was assessed during the period 2002–2004 and in 2014. Methods – Water samples were collected with a 20 µm plankton net and with a slime aspirator (20 ml capacity) from the surface of the bottom. One aliquot of each sample was fixed for SEM observation; the fresh part of the sample was analysed using light microscope. Physical and chemical properties of the water (pH, temperature, conductivity, phosphates and ammonium salt contents) were measured. Diversity indices were calculated (Shannon-Wiener, evenness, Margalef and Simpson) and UPGMA cluster analysis was applied to discern differences among euglenoid assemblages.Key results – In total, 63 euglenophyte taxa were found. The euglenophyte community was dominated by species belonging to the Trachelomonas genus (29 taxa). The most abundant and constant component were widespread and common species such as T. caudata, T. hispida, T. intermedia, T. volvocina and T. volvocinopsis. They usually occurred in very high densities. We also found some rarely reported euglenophytes including Euglena granulata, Trachelomonas lemmermannii, and T. sydneyensis. Conclusions – Euglenophytes were, with a few exceptions, the only group inhabiting the pond. Representatives of other groups such as diatoms or Scenedesmus species were recorded only occasionally. Nearly half of the taxa that were recorded in the first period (2002–2004) were found again after ten years. Of special concern was taxa belonging to the genus Trachelomonas. Trachelomonads, although known to represent taxa preferring waters moderately rich in nutrients, were very numerous in the investigated pond, which was enriched in phosphorus and nitrogen compounds.

scholarly journals Investigations on the combustion of hydrocarbons II-Absorption spectra and chemical properties of intermediates

1935 ◽  
Vol 152 (876) ◽  
pp. 378-402 ◽  
Author(s):  
Alfred Rene Jean Paul Ubbelohde ◽  
Alfred Charles Egerton
Keyword(s):  
Absorption Coefficient ◽  
Organic Acids ◽  
Ethyl Acetate ◽  
Induction Period ◽  
Absorption Spectra ◽  
Chemical Properties ◽  
Iron Carbonyl ◽  
Slow Combustion ◽  
Higher Hydrocarbons ◽  
And Chemical Properties

The investigations recorded here are a development of the work of Egerton and Pidgeon on the absorption spectra of burning hydrocarbons, which had included investigations of the absorption and slow combustion of alcohols up to amyl alcohols, aldehydes up to valeraldehyde, acids up to butyric; amylene, ethylene, ethyl acetate, ethyl hydroperoxide, diethyl, peroxide, and of anti-knocks such as lead tetraethyl, iron carbonyl, butyl iodide, and aniline. The results were compared with the slow combustion of the normal hydrocarbons up to pentane, in the same apparatus. The only intermediates which could be demonstrated spectroscopically in the slow combustion of hydrocarbons were formaldehyde and organic acids, mainly because only these substances have a sufficiently large absorption coefficient to he detectable at the concentrations occurring. In addition, a characteristic hand was discovered at the end of the (pseudo) induction period, in the slow combustion of the higher hydrocarbons, though the molecule responsible for it was not identified, in spite of a considerable search among the ordinary products of slow combustion.

scholarly journals Influences of surface chemistry and swelling of salt-treated polyelectrolyte multilayers on migration of smooth muscle cells

2012 ◽  
Vol 9 (77) ◽  
pp. 3455-3468 ◽  
Author(s):  
Lulu Han ◽  
Zhengwei Mao ◽  
Jindan Wu ◽  
Yuying Zhang ◽  
Changyou Gao
Keyword(s):  
Smooth Muscle ◽  
Cell Migration ◽  
Surface Chemistry ◽  
Smooth Muscle Cells ◽  
Focal Adhesion ◽  
Chemical Properties ◽  
Muscle Cells ◽  
Cellular Migration ◽  
Gene Expressions ◽  
And Migration

The cell migration plays a crucial role in a variety of physiological and pathological processes and can be regulated by the cell–substrate interactions. We found previously that the poly(sodium 4-styrenesulphonate) (PSS)/poly(diallyldimethylammonium) chloride (PDADMAC) multilayers post-treated in 1–5 M NaCl solutions result in continuous changes of their physico-chemical properties such as thickness, chemical composition, surface charge, swelling ratio and wettability. In this study, the responses of human smooth muscle cells (SMCs) on these salt-treated multilayers, particularly the governing factors of cellular migration that offer principles for designing therapeutics and implants, were disclosed. The cell migration rate was slowest on the 3 M NaCl-treated multilayers, which was comparable with that on tissue culture plates, but it was highest on 5 M NaCl-treated multilayers. To elucidate the intrinsic mechanisms, cell adhesion, proliferation, adhesion and related gene expressions were further investigated. The SMCs preferred to attach, spread and proliferate on the PSS-dominated surfaces with well-organized focal adhesion and actin fibres, especially on the 3 M NaCl-treated multilayers, while were kept round and showed low viability on the PDADMAC-dominated surfaces. The relative mRNA expression levels of adhesion-related genes such as fibronectin, laminin and focal adhesion kinase, and migration-related genes such as myosin IIA and Cdc42 were compared to explain the different cellular behaviours. These results reveal that the surface chemistry and the swelling of the salt-treated multilayers govern the cell migration behaviours.

scholarly journals Nano-Hydroxyapatite Accelerates Vascular Calcification by Inhibiting Lysosomal Acidification in Smooth Muscle Cells.

2021 ◽  
Author(s):  
Qi Liu ◽  
Yi Luo ◽  
Yun Zhao ◽  
Pingping Xiang ◽  
Jinyun Zhu ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Vascular Calcification ◽  
Chemical Properties ◽  
Muscle Cells ◽  
Calcium Deposition ◽  
Rapid Progression ◽  
Autophagic Flux

Abstract Background: Vascular calcification (VC) is a common characteristic of aging, diabetes, chronic renal failure, and atherosclerosis. The basic component of VC is hydroxyapatite (HAp). Nano-sized HAp (nHAp) has been identified as the initiator of pathological calcification of vasculature. However, whether nHAp can induce calcification in vivo and the mechanism of nHAp in the progression of VC remains unclear.Results: We discovered that nHAp existed both in vascular smooth muscle cells (VSMCs) and their extracellular matrix (ECM) in the calcified arteries from patients. Synthetic nHAp had similar morphological and chemical properties as natural nHAp recovered from calcified artery. nHAp induced rapid progression of VC by stimulating osteogenic differentiation and accelerating mineralization of VSMCs in vitro. Synthetic nHAp could also directly induce VC in vivo. Mechanistically, nHAp was internalized into lysosome, which impaired lysosome vacuolar H+-ATPase for its acidification, therefore blocked autophagic flux in VSMCs. The accumulated autophagosomes and autolysosomes were converted into calcium-containing exosomes which were secreted into ECM and accelerated vascular calcium deposit. Inhibition of exosome release in VSMCs decreased calcium deposition. Conclusions: Our results illustrated a novel mechanism of nHAp-induced vascular calcification. Understanding the role of nHAp in autophagy-lysosome-exosome pathway in SMCs could have great clinical significance in preventing the progression of VC.

scholarly journals The Role of Smooth Muscle Cells in Vessel Wall Pathophysiology and Reconstruction Using Bioactive Synthetic Polymers

2011 ◽  
pp. 419-437 ◽  
Author(s):  
M. PAŘÍZEK ◽  
K. NOVOTNÁ ◽  
L. BAČÁKOVÁ
Keyword(s):  
Cell Culture ◽  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Vascular Tissue ◽  
Culture Media ◽  
Vascular Grafts ◽  
Chemical Properties ◽  
Vascular Diseases ◽  
Cyclic Strain ◽  
Muscle Cells

This review summarizes recent trends in the construction of bioartificial vascular replacements, i.e. hybrid grafts containing synthetic polymeric scaffolds and cells. In these advanced replacements, vascular smooth muscle cells (VSMC) should be considered as a physiological component, although it is known that activation of the migration and proliferation of VSMC plays an important role in the onset and development of vascular diseases, and also in restenosis of currently used vascular grafts. Therefore, in novel bioartificial vascular grafts, VSMCs should be kept in quiescent mature contractile phenotype. This can be achieved by (1) appropriate physical and chemical properties of the material, such as its chemical composition, polarity, wettability, surface roughness and topography, electrical charge and conductivity, functionalization with biomolecules and mechanical properties, (2) appropriate cell culture conditions, such as composition of cell culture media and dynamic load, namely cyclic strain, and (3) the presence of a confluent, mature, semipermeable, non-thrombogenic and non-immunogenic endothelial cell (EC) barrier, covering the luminal surface of the graft and separating the VSMCs from the blood. Both VSMCs and ECs can also be differentiated from stem and progenitor cells of various sources. In the case of degradable scaffolds, the material will gradually be removed by the cells and will be replaced by their own new extracellular matrix. Thus, the material component in advanced blood vessel substitutes acts as a temporary scaffold that promotes regeneration of the damaged vascular tissue.

scholarly journals Plankton and Macrobiota Composition and Diversity of Three Tropical Freshwaters Rivers in Ogun and Ondo States, Southwest Nigeria

2016 ◽  
Vol 8 (2) ◽  
pp. 246-255
Author(s):  
Taofikat Abosede ADESALU ◽  
Olakunbi Anike KUNRUNMI ◽  
Muyideen Owonire LAWAL
Keyword(s):  
Ph Value ◽  
Chemical Properties ◽  
Common Species ◽  
Water Bodies ◽  
Dominant Group ◽  
Ogun State ◽  
Tropical Freshwaters ◽  
Southwest Nigeria ◽  
Ondo State ◽  
Physical And Chemical

Three different rivers in Ogun and Ondo states were investigated for both micro and macro-biota of the water bodies. Several physical and chemical properties of these rivers were determined. The pH value of the studied water bodies was essentially neutral with salinity values between 0.02 - 4.0‰. Microalgae communities were represented by three divisions: Cyanophyta, Bacillariophyta and Chlorophyta at Oluwa and Ifara Rivers (Ondo state), while at Ibefun River (Ogun state), five divisions: Cyanophyta, Bacillariophyta, Chlorophyta, Euglenophyta and Pyrrhophyta were identified. Diatoms dominated these water bodies, with Navicula radiosa Kutz. at Ifara River, Fragilaria sp. in Oluwa River, while out of 90 algal taxa identified in Ibefun river, 64 were diatoms species belonging to 26 genera, with Melosira sp. and Synedra sp. recording the highest numbers of cell count. Dinoflagellates recorded only Peridinium sp. while Phacus orbicularis Hubner and Trachelomonas sp. dominated the euglenoids. For the zooplankton composition at Ibefun, rotifers (75.95%) were represented by Brachionus sp., which recorded 62.03%, and Gastropus sp. with 13.92% of the total zooplankton, thus dominated the spectrum, while the copepod recorded 22.78% of the total organisms, with Copilia sp. and Euchirella sp. having 8.86% each. The macrobenthic invertebrates were represented by 3 taxa, belonging to 3 groups, with the dominant group Insecta accounted for 57% of the total individuals (7 individuals/m2), while Oligochaeta and Hirudinea accounted for 29% and 14% respectively of the total individuals at Oluwa and Ifara Rivers. At Ibefun River, the macrobenthic invertebrates were represented by 5 taxa, belonging to 3 groups, Bivalves, Oligochaeta and Insecta, with bivalves being the dominant group (51.7% of the total individuals, as 64 individuals/m2), while Oligochaeta and Insecta accounted for 26.6% and 21.9% respectively of the total individuals. The dominant taxon, Macoma cumana, accounted for 42.2%. A total of seventeen (17) finfish and shellfish species comprised of thirteen (13) finfish and four (4) shellfish species were recorded, being representative of freshwater and brackish water species; Clarias anguillaris (Clariidae), Tilapia zilli (Cichlidae), Chrysichthys nigrodigitatus (Bagridae), Alestes spp. and Macrobrachium vollenhovenii (Palaemonidae) were the most common species observed.

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