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Irena Kaczmarska - One of the best experts on this subject based on the ideXlab platform.
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RESEARCH Open Access
2016Co-Authors: Equal Contributorsmichael L Macgillivary, Irena KaczmarskaAbstract:Paralia (Bacillariophyta) stowaways in ship ballast: implications for biogeography and diversity o
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Auxosporulation in Paralia guyana MacGillivary (Bacillariophyta) and Possible New Insights into the Habit of the Earliest Diatoms.
PLOS ONE, 2015Co-Authors: Irena Kaczmarska, James M. EhrmanAbstract:Background Diatoms are one of the most ecologically important aquatic micro-eukaryotes. As a group unambiguously recognized as diatoms, they seem to have appeared relatively recently with a limited record of putative remains from oldest sediments. In contrast, molecular clock estimates for the earliest possible emergence of diatoms suggest a considerably older date. Depending on the analysis, Paralia and Leptocylindrus have been recovered within the basal molecular divergences of diatoms. Thus these genera may be in the position to inform on characters that the earliest diatoms possessed. Findings Here we present auxospore development and structure of initial and post-auxospore cells in a representative of the ancient non-polar centric genus Paralia. Their initial frustules showed unusual, but not unprecedented, spore-like morphology. Similarly, initial frustules of Leptocylindrus have been long considered resting spores and a unique peculiarity of this genus. However, even though spore-like in appearance, initial cells of Paralia readily resumed mitotic divisions. In addition, Paralia post-auxospore cells underwent several rounds of mitoses in a multi-step process of building a typical, “perfect” vegetative valve. This degree of heteromorphy immediately post-auxosporulation is thus far unknown among the diatoms. Implications A spore-related origin of diatoms has already been considered, most recently in the form of the “multiplate diploid cyst” hypothesis. Our discovery that the initial cells in some of the most ancient diatom lineages are structurally spore-like is consistent with that hypothesis because the earliest diatoms may be expected to look somewhat similar to their ancestors. We speculate that because the earliest diatoms may have appeared less diatom-like and more spore-like, they could have gone unrecognized as such in the Triassic/Jurassic sediments. If correct, diatoms may indeed be much older than the fossil record indicates, and possibly more in line with some molecular clock predictions.
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Paralia (Bacillariophyta) stowaways in ship ballast: implications for biogeography and diversity of the genus
Journal of Biological Research-Thessaloniki, 2015Co-Authors: Michael L Macgillivary, Irena KaczmarskaAbstract:Background The genus Paralia Heiberg is one of the most recognizable, widely distributed and commonly reported diatoms from contemporary coastal marine environments and ship ballast. Species discovery has historically been made in diatoms through the recognition of morphological discontinuities between specimens, first using light and later electron microscopy. However, recently, morphologically semi-cryptic species of Paralia were delineated using genetic analyses, among mostly tropical and subtropical sites. Results Ten morphological characters of the frustules and sequence fragments from the nuclear genome (conserved 18S regions of ribosomal RNA and the variable internal transcribed spacer [ITS]), and from the RuBisCo large subunit ( rbc L) gene of the chloroplast genome were examined. Frustule morphology did not segregate species, however, comparisons of sequence fragments and ITS2 secondary structures yielded a new species from North American waters, P. guyana (with four genodemes), and another widely-distributed species, P. marina . The latter was lecto- and epitypified here because it is most similar to specimens in the type preparation BM1021 representing Smith’s concept of the species. Paralia marina and certain genodemes of P. guyana were morphologically cryptic. Only those genodemes of P. guyana that possess prickly separation valves could be morphologically distinguished from P. marina with relative confidence in SEM preparations. All clones established from chains isolated from the ballast sediment of the ships sailing along the Atlantic coast of North America belonged to P. guyana . All DNA sequences of preserved Paralia chains recovered from the three trans-Atlantic voyages (TAVs) samples arriving to eastern Canada from Europe shared 100% identity with P. marina . Conclusion First, if the x ¯ $$ \overline{x} $$ = 130592 P. marina cells per ballast tank at the end of the TAVs represents their abundance in ballast tanks of similar crossings and following mid-ocean ballast water exchange, then this diatom, if de-ballasted, exerts a strong and continued propagule pressure on Eastern Canadian coasts. Despite this, as of 2009, P. marina was found only in Cheticamp, Nova Scotia, Canada. Second, genetic analysis readily segregated cryptic and semi-cryptic taxa of Paralia , highlighting the usefulness of the molecular approach to species recognition, e.g., in programs monitoring alien introductions.
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Paralia (Bacillariophyta) stowaways in ship ballast: implications for biogeography and diversity of the genus
Journal of Biological Research-Thessaloniki, 2015Co-Authors: Michael L Macgillivary, Irena KaczmarskaAbstract:The genus Paralia Heiberg is one of the most recognizable, widely distributed and commonly reported diatoms from contemporary coastal marine environments and ship ballast. Species discovery has historically been made in diatoms through the recognition of morphological discontinuities between specimens, first using light and later electron microscopy. However, recently, morphologically semi-cryptic species of Paralia were delineated using genetic analyses, among mostly tropical and subtropical sites. Ten morphological characters of the frustules and sequence fragments from the nuclear genome (conserved 18S regions of ribosomal RNA and the variable internal transcribed spacer [ITS]), and from the RuBisCo large subunit (rbcL) gene of the chloroplast genome were examined. Frustule morphology did not segregate species, however, comparisons of sequence fragments and ITS2 secondary structures yielded a new species from North American waters, P. guyana (with four genodemes), and another widely-distributed species, P. marina. The latter was lecto- and epitypified here because it is most similar to specimens in the type preparation BM1021 representing Smith’s concept of the species. Paralia marina and certain genodemes of P. guyana were morphologically cryptic. Only those genodemes of P. guyana that possess prickly separation valves could be morphologically distinguished from P. marina with relative confidence in SEM preparations. All clones established from chains isolated from the ballast sediment of the ships sailing along the Atlantic coast of North America belonged to P. guyana. All DNA sequences of preserved Paralia chains recovered from the three trans-Atlantic voyages (TAVs) samples arriving to eastern Canada from Europe shared 100% identity with P. marina. First, if the $$ \overline{x} $$ = 130592 P. marina cells per ballast tank at the end of the TAVs represents their abundance in ballast tanks of similar crossings and following mid-ocean ballast water exchange, then this diatom, if de-ballasted, exerts a strong and continued propagule pressure on Eastern Canadian coasts. Despite this, as of 2009, P. marina was found only in Cheticamp, Nova Scotia, Canada. Second, genetic analysis readily segregated cryptic and semi-cryptic taxa of Paralia, highlighting the usefulness of the molecular approach to species recognition, e.g., in programs monitoring alien introductions.
Zhekun Zhou - One of the best experts on this subject based on the ideXlab platform.
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fossil endocarps of aralia araliaceae from the upper pliocene of yunnan in southwest china and their biogeographical implications
Review of Palaeobotany and Palynology, 2015Co-Authors: Frederic M B Jacques, Xiang Hui Xiao, Yongjiang Huang, Zhekun Zhou, Li WangAbstract:Aralia stratosa H. Zhu, Y.J. Huang et Z.K. Zhou sp. nov. is described based on fossil endocarps from the upper Pliocene of northwest Yunnan in southwest China. The endocarps are characterized by a semicircular to elliptic outline in the lateral view, an apical beak-like structure bending towards the ventral side, and a transversely wrinkled surface, collectively indicating taxonomical inclusion in the genus Aralia (Araliaceae). The new fossil taxon is compared with nine extant species of Aralia based on endocarp morphology and anatomy, showing the carpological resemblance to A. echinocaulis. Aralia stratosa sp. nov. represents the first confirmed fossil record from lower latitudes in the Northern Hemisphere. This implies a southerly biogeographical range for this genus than was previously interpreted. The fossil record of Aralia suggests a Cretaceous origin in North America and an Eocene dispersal to eastern Asia, likely via the Bering land bridge, followed by Miocene establishment in Europe. The genus likely began to inhabit lower latitudes in eastern Asia no later than the late Pliocene, which is in line with results from molecular analyses. All these may suggest a southward distributional change probably associated with the global cooling and northern acidification. (C) 2015 Elsevier B.V. All rights reserved.
Haixue Kuang - One of the best experts on this subject based on the ideXlab platform.
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simultaneous determination of four triterpenoid saponins in aralia elata leaves by hplc elsd combined with hierarchical clustering analysis
Phytochemical Analysis, 2017Co-Authors: Baimei Li, Qiuhong Wang, Zhibin Wang, Hongwei Zhang, Hai Jiang, Haixue KuangAbstract:Introduction Aralia elata leaves are known to have several biological activities, including anti-arrythmia, antitumor, anti-inflammatory, anti-fatigue, antimicrobial and antiviral effects. Our previous study found that triterpenoid saponins from the leaves of A. elata had antitumor effects. Quantification of the triterpenoids is important for the quality control of A. elata leaves. Objective To establish high-performance liquid chromatography coupled with evaporative light scattering detection (HPLC-ELSD) for the simultaneous determination of four major triterpenoid saponins, including Aralia-saponin IV, Aralia-saponin VI, 3-O-β-d- glucopyranosyl-(1 → 3)-β-d-glucopyranosyl-(1 → 3)-β-d-glucopyranosyl oleanolic acid 28-O-β-d-glucopyranoside (Aralia-saponin TTP)and Aralia-saponin V. Methodology The separation was carried out on a Dikma Diamonsil C18 column (4.6 mm × 250 mm, 5 μm) efficiently with gradient elution consisting of acetonitrile and water. Results All calibration curves showed good linear regression (R2 > 0.9996) within the ranges of tested concentrations. This validated method was applied to determine the contents of the four major triterpenoid saponins in 53 samples from different regions of northeast China. Hierarchical clustering analysis was first used to classify and differentiate Aralia elata leaves. Conclusion The method developed was successfully applied to analyse four major triterpenoid saponins in Aralia elata leaves which is helpful for quality control of the herb. Copyright © 2017 John Wiley & Sons, Ltd.
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determination and pharmacokinetic study of two triterpenoid saponins in rat plasma after oral administration of the extract of aralia elata leaves by uhplc esi ms ms
Journal of Chromatography B, 2015Co-Authors: Chunjuan Yang, Bingyou Yang, Qiuhong Wang, Zhibin Wang, Yonghai Meng, Qi Wang, Qiong Wu, Haixue KuangAbstract:Abstract Aralia elata (Miq.) Seems (A. elata) grow in Northeast China and the total saponins of A. elata is used to auxiliary treatment for the acute hepatitis, chronic hepatitis and the transaminase on the high side. Aralia-saponinV and Aralia-saponinVI are the major bioactive saponins in A. elata leaves. A selective and sensitive UHPLC–MS/MS method was developed and validated for the determination and pharmacokinetic study of Aralia-saponinV and Aralia-saponinVI indwelling the extract in rat plasma in this article. The sample pretreatment involved a one-step extraction of 0.2 mL plasma with methanol. Shengmaxinside C was used as internal standard (I.S.). The separation was carried out on an Agilent SB-C18 column (1.8 μm, 50 mm × 2.1 mm) at 30 °C with a mobile phase of acetonitrile–5 mM ammonium acetate (90:10, v/v) at a flow rate of 0.2 mL/min. The detection was performed on a triple quadrupole tandem mass spectrometer by multiple reaction monitoring (MRM) mode via electrospray ionization (ESI) source operating in the negative ionization mode. The optimized mass transition ion-pairs (m/z) monitored for Aralia-saponinV, Aralia-saponinVI and I.S. were 1103.2/941.2, 1119.2/957.0 and 707.0/647.1, respectively. The current UHPLC–MS/MS assay method was validated for linearity, intra-day and inter-day precisions, accuracy, extraction recovery and stability, and it was suitable for the pharmacokinetic studies of the two saponins after oral administration of extract of A. elata leaves. The lower limits of quantification were 5.70 ng/mL for Aralia-saponinV and 6.15 ng/mL for Aralia-saponinVI. Intra-day and inter-day precisions were less than 7.4% and the accuracy range was from 1.19% to 8.60%. The mean extraction recoveries of analytes and I.S. from rat plasma were all more than 89.5%. This paper described a simple, sensitive and validated UHPLC–MS/MS method for simultaneous determination of Aralia-saponinV and Aralia-saponinVI in rat plasma after oral administration of the extract of A. elata leaves, and investigated on their pharmacokinetic studies as well.
Zhibin Wang - One of the best experts on this subject based on the ideXlab platform.
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simultaneous determination of four triterpenoid saponins in aralia elata leaves by hplc elsd combined with hierarchical clustering analysis
Phytochemical Analysis, 2017Co-Authors: Baimei Li, Qiuhong Wang, Zhibin Wang, Hongwei Zhang, Hai Jiang, Haixue KuangAbstract:Introduction Aralia elata leaves are known to have several biological activities, including anti-arrythmia, antitumor, anti-inflammatory, anti-fatigue, antimicrobial and antiviral effects. Our previous study found that triterpenoid saponins from the leaves of A. elata had antitumor effects. Quantification of the triterpenoids is important for the quality control of A. elata leaves. Objective To establish high-performance liquid chromatography coupled with evaporative light scattering detection (HPLC-ELSD) for the simultaneous determination of four major triterpenoid saponins, including Aralia-saponin IV, Aralia-saponin VI, 3-O-β-d- glucopyranosyl-(1 → 3)-β-d-glucopyranosyl-(1 → 3)-β-d-glucopyranosyl oleanolic acid 28-O-β-d-glucopyranoside (Aralia-saponin TTP)and Aralia-saponin V. Methodology The separation was carried out on a Dikma Diamonsil C18 column (4.6 mm × 250 mm, 5 μm) efficiently with gradient elution consisting of acetonitrile and water. Results All calibration curves showed good linear regression (R2 > 0.9996) within the ranges of tested concentrations. This validated method was applied to determine the contents of the four major triterpenoid saponins in 53 samples from different regions of northeast China. Hierarchical clustering analysis was first used to classify and differentiate Aralia elata leaves. Conclusion The method developed was successfully applied to analyse four major triterpenoid saponins in Aralia elata leaves which is helpful for quality control of the herb. Copyright © 2017 John Wiley & Sons, Ltd.
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determination and pharmacokinetic study of two triterpenoid saponins in rat plasma after oral administration of the extract of aralia elata leaves by uhplc esi ms ms
Journal of Chromatography B, 2015Co-Authors: Chunjuan Yang, Bingyou Yang, Qiuhong Wang, Zhibin Wang, Yonghai Meng, Qi Wang, Qiong Wu, Haixue KuangAbstract:Abstract Aralia elata (Miq.) Seems (A. elata) grow in Northeast China and the total saponins of A. elata is used to auxiliary treatment for the acute hepatitis, chronic hepatitis and the transaminase on the high side. Aralia-saponinV and Aralia-saponinVI are the major bioactive saponins in A. elata leaves. A selective and sensitive UHPLC–MS/MS method was developed and validated for the determination and pharmacokinetic study of Aralia-saponinV and Aralia-saponinVI indwelling the extract in rat plasma in this article. The sample pretreatment involved a one-step extraction of 0.2 mL plasma with methanol. Shengmaxinside C was used as internal standard (I.S.). The separation was carried out on an Agilent SB-C18 column (1.8 μm, 50 mm × 2.1 mm) at 30 °C with a mobile phase of acetonitrile–5 mM ammonium acetate (90:10, v/v) at a flow rate of 0.2 mL/min. The detection was performed on a triple quadrupole tandem mass spectrometer by multiple reaction monitoring (MRM) mode via electrospray ionization (ESI) source operating in the negative ionization mode. The optimized mass transition ion-pairs (m/z) monitored for Aralia-saponinV, Aralia-saponinVI and I.S. were 1103.2/941.2, 1119.2/957.0 and 707.0/647.1, respectively. The current UHPLC–MS/MS assay method was validated for linearity, intra-day and inter-day precisions, accuracy, extraction recovery and stability, and it was suitable for the pharmacokinetic studies of the two saponins after oral administration of extract of A. elata leaves. The lower limits of quantification were 5.70 ng/mL for Aralia-saponinV and 6.15 ng/mL for Aralia-saponinVI. Intra-day and inter-day precisions were less than 7.4% and the accuracy range was from 1.19% to 8.60%. The mean extraction recoveries of analytes and I.S. from rat plasma were all more than 89.5%. This paper described a simple, sensitive and validated UHPLC–MS/MS method for simultaneous determination of Aralia-saponinV and Aralia-saponinVI in rat plasma after oral administration of the extract of A. elata leaves, and investigated on their pharmacokinetic studies as well.
Michael L Macgillivary - One of the best experts on this subject based on the ideXlab platform.
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Paralia (Bacillariophyta) stowaways in ship ballast: implications for biogeography and diversity of the genus
Journal of Biological Research-Thessaloniki, 2015Co-Authors: Michael L Macgillivary, Irena KaczmarskaAbstract:Background The genus Paralia Heiberg is one of the most recognizable, widely distributed and commonly reported diatoms from contemporary coastal marine environments and ship ballast. Species discovery has historically been made in diatoms through the recognition of morphological discontinuities between specimens, first using light and later electron microscopy. However, recently, morphologically semi-cryptic species of Paralia were delineated using genetic analyses, among mostly tropical and subtropical sites. Results Ten morphological characters of the frustules and sequence fragments from the nuclear genome (conserved 18S regions of ribosomal RNA and the variable internal transcribed spacer [ITS]), and from the RuBisCo large subunit ( rbc L) gene of the chloroplast genome were examined. Frustule morphology did not segregate species, however, comparisons of sequence fragments and ITS2 secondary structures yielded a new species from North American waters, P. guyana (with four genodemes), and another widely-distributed species, P. marina . The latter was lecto- and epitypified here because it is most similar to specimens in the type preparation BM1021 representing Smith’s concept of the species. Paralia marina and certain genodemes of P. guyana were morphologically cryptic. Only those genodemes of P. guyana that possess prickly separation valves could be morphologically distinguished from P. marina with relative confidence in SEM preparations. All clones established from chains isolated from the ballast sediment of the ships sailing along the Atlantic coast of North America belonged to P. guyana . All DNA sequences of preserved Paralia chains recovered from the three trans-Atlantic voyages (TAVs) samples arriving to eastern Canada from Europe shared 100% identity with P. marina . Conclusion First, if the x ¯ $$ \overline{x} $$ = 130592 P. marina cells per ballast tank at the end of the TAVs represents their abundance in ballast tanks of similar crossings and following mid-ocean ballast water exchange, then this diatom, if de-ballasted, exerts a strong and continued propagule pressure on Eastern Canadian coasts. Despite this, as of 2009, P. marina was found only in Cheticamp, Nova Scotia, Canada. Second, genetic analysis readily segregated cryptic and semi-cryptic taxa of Paralia , highlighting the usefulness of the molecular approach to species recognition, e.g., in programs monitoring alien introductions.
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Paralia (Bacillariophyta) stowaways in ship ballast: implications for biogeography and diversity of the genus
Journal of Biological Research-Thessaloniki, 2015Co-Authors: Michael L Macgillivary, Irena KaczmarskaAbstract:The genus Paralia Heiberg is one of the most recognizable, widely distributed and commonly reported diatoms from contemporary coastal marine environments and ship ballast. Species discovery has historically been made in diatoms through the recognition of morphological discontinuities between specimens, first using light and later electron microscopy. However, recently, morphologically semi-cryptic species of Paralia were delineated using genetic analyses, among mostly tropical and subtropical sites. Ten morphological characters of the frustules and sequence fragments from the nuclear genome (conserved 18S regions of ribosomal RNA and the variable internal transcribed spacer [ITS]), and from the RuBisCo large subunit (rbcL) gene of the chloroplast genome were examined. Frustule morphology did not segregate species, however, comparisons of sequence fragments and ITS2 secondary structures yielded a new species from North American waters, P. guyana (with four genodemes), and another widely-distributed species, P. marina. The latter was lecto- and epitypified here because it is most similar to specimens in the type preparation BM1021 representing Smith’s concept of the species. Paralia marina and certain genodemes of P. guyana were morphologically cryptic. Only those genodemes of P. guyana that possess prickly separation valves could be morphologically distinguished from P. marina with relative confidence in SEM preparations. All clones established from chains isolated from the ballast sediment of the ships sailing along the Atlantic coast of North America belonged to P. guyana. All DNA sequences of preserved Paralia chains recovered from the three trans-Atlantic voyages (TAVs) samples arriving to eastern Canada from Europe shared 100% identity with P. marina. First, if the $$ \overline{x} $$ = 130592 P. marina cells per ballast tank at the end of the TAVs represents their abundance in ballast tanks of similar crossings and following mid-ocean ballast water exchange, then this diatom, if de-ballasted, exerts a strong and continued propagule pressure on Eastern Canadian coasts. Despite this, as of 2009, P. marina was found only in Cheticamp, Nova Scotia, Canada. Second, genetic analysis readily segregated cryptic and semi-cryptic taxa of Paralia, highlighting the usefulness of the molecular approach to species recognition, e.g., in programs monitoring alien introductions.
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A readily available SEM substrate for a random orientation of diatom frustules
Diatom Research, 2011Co-Authors: Michael L Macgillivary, James M. EhrmanAbstract:The surface of a vinyl phonograph record was used for SEM imaging of the valves of the centric diatom Paralia Heiberg. This simple method allowed the imaging of various orientations and views of diatom valves without tilting or rotating the SEM stage. This mounting method proved to be more efficient than using traditional flat substrates such as cover slips or polycarbonate filters. Additionally, playing the phonograph record with mounted diatoms prior to SEM imaging fractured some Paralia valves and allowed the viewing of internal morphology. The use of this SEM substrate would be beneficial for other diatom species where it is difficult to match valve and face view morphology, and for species where producing different orientations of the valve is laborious.
