scholarly journals Distribution and abundance of dinoflagellates from the coastal waters of Karachi, Pakistan, northern part of the Arabian Sea

2022 ◽  
Vol 82 ◽  
Author(s):  
F. N. Khokhar ◽  
N. Ahmed ◽  
A. Ali ◽  
K. Gabol ◽  
A. R. Khooharo ◽  
...  
Keyword(s):  
Shannon Index ◽  
Strong Positive Correlation ◽  
Alexandrium Minutum ◽  
Alexandrium Catenella ◽  
Seasonal And Spatial Variations ◽  
Total Phytoplankton ◽  
Shore Station ◽  
Near Shore ◽  
Percent Contribution ◽  
Offshore Station

Abstract The present study reports on seasonal and spatial variations in diversity, distribution and abundance of dinoflegellates and indicates the presence of HAB species in Pakistan waters. A total of 179 taxa, recorded in this study from offshore and near-shore waters, belong to 41 genera in 26 families and 10 orders. The high species count (149 species) was recorded from Manora Island offshore station (MI-1) and 105 spp, 109 spp and 115 spp were encountered from the Mubarak village offshore station (MV-1), Manora near shore station (MI-2) and Mubarak Village near-shore station (MV-2) respectively. Tripos furca was the dominant and frequently occurring species (> 1 x103 to > 25 x103 cells L-1 from coastal and >1x 105 cells L-l from near-shore stations) in addition to less abundant Alexandrium catenella, Alexandrium sp., Alexandrium minutum, and Prorocentrum micans (>103 to 25x 103cells/L). Another 44 species occurred in relatively low numbers (<103 cell L-l). Seventy species were found throughout the study period at all four stations. High number of species in three genera (Tripos (38), Protoperidinium (34) and Prorocentrum (20) was recorded. Potently toxic (16 genera 43 species) and HAB related (19 genera and 30 species) dinoflagellate taxa were also recorded. The percent contribution of dinoflagellates in total phytoplankton population generally remained below 20% except for a few instances. Manora Island stations had comparatively higher Shannon index and equitability and slightly lower dominance index. The PCA plot showed strong positive correlation among chlorophyll-a concentration, dissolved oxygen, total number of phytoplankton and dinoflagellates.

scholarly journals Limacina helicina shell dissolution as an indicator of declining habitat suitability owing to ocean acidification in the California Current Ecosystem

2014 ◽  
Vol 281 (1785) ◽  
pp. 20140123 ◽  
Author(s):  
N. Bednaršek ◽  
R. A. Feely ◽  
J. C. P. Reum ◽  
B. Peterson ◽  
J. Menkel ◽  
...  
Keyword(s):  
Ocean Acidification ◽  
Natural Environment ◽  
Habitat Suitability ◽  
California Current ◽  
Strong Positive Correlation ◽  
Near Shore ◽  
Biological Impacts ◽  
Biological Sampling ◽  
Physical And Chemical ◽  
Chemical Water

Few studies to date have demonstrated widespread biological impacts of ocean acidification (OA) under conditions currently found in the natural environment. From a combined survey of physical and chemical water properties and biological sampling along the Washington–Oregon–California coast in August 2011, we show that large portions of the shelf waters are corrosive to pteropods in the natural environment. We show a strong positive correlation between the proportion of pteropod individuals with severe shell dissolution damage and the percentage of undersaturated water in the top 100 m with respect to aragonite. We found 53% of onshore individuals and 24% of offshore individuals on average to have severe dissolution damage. Relative to pre-industrial CO 2 concentrations, the extent of undersaturated waters in the top 100 m of the water column has increased over sixfold along the California Current Ecosystem (CCE). We estimate that the incidence of severe pteropod shell dissolution owing to anthropogenic OA has doubled in near shore habitats since pre-industrial conditions across this region and is on track to triple by 2050. These results demonstrate that habitat suitability for pteropods in the coastal CCE is declining. The observed impacts represent a baseline for future observations towards understanding broader scale OA effects.

scholarly journals Heavy metal uptake of near-shore benthic foraminifera during multi-metal culturing experiments

2021 ◽  
Author(s):  
Sarina Schmidt ◽  
Edmund Charles Hathorne ◽  
Joachim Schönfeld ◽  
Dieter Garbe-Schönberg
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Mining Industry ◽  
Anthropogenic Pollution ◽  
Anthropogenic Sources ◽  
Strong Positive Correlation ◽  
Clear Trend ◽  
Direct Function ◽  
Metal Concentrations ◽  
Near Shore

Abstract. Heavy metal pollution originating from anthropogenic sources, e.g., mining, industry and extensive land use, is increasing in many parts of the world and influences coastal marine environments for a long time. The elevated input of heavy metals into the marine system potentially affects the biota because of their toxicity, persistence and bioaccumulation. An emerging tool for environmental applications is the heavy metal incorporation into foraminiferal tests calcite, which facilitates monitoring of anthropogenic footprints on recent and past environmental systems. The aim of this study is to investigate whether the incorporation of heavy metals in foraminifera is a direct function of their concentration in seawater. Culturing experiments with a mixture of dissolved chromium (Cr), manganese (Mn), nickel (Ni), copper (Cu), zinc (Zn), silver (Ag), cadmium (Cd), tin (Sn), mercury (Hg) and lead (Pb) in artificial seawater were carried out over a wide concentration range to assess the uptake of heavy metals by the near-shore foraminiferal species Ammonia aomoriensis, Ammonia batava and Elphidium excavatum. Seawater analysis exhibited the increasing metal concentrations between culturing phases and revealed high metal concentrations in the beginning of the culturing phases due to the punctual metal addition. Furthermore, a loss of metals during the culturing process was discovered, which lead to a deviation between the expected and the actual concentrations of the metals in seawater. Laser ablation ICP-MS analysis of the newly formed calcite revealed species-specific differences in the incorporation of heavy metals. The foraminiferal calcite of all three species reveals a strong positive correlation with Pb and Ag concentrations in the culturing medium. Ammonia aomoriensis further showed a correlation with Mn and Cu, A. batava with Mn and Hg and E. excavatum with Cr and Ni, and partially also with Hg. Zn, Sn and Cd showed no clear trend for the species studied, which may be caused by the little variation of these metals in seawater. Our calibrations and the calculated partition coefficients render A. aomoriensis, A. batava and E. excavatum as natural archives that enable the direct quantification of metals in polluted and pristine environments. This in turn allows monitoring of the ecosystem status of areas that are potentially under the threat of anthropogenic pollution in order to evaluate contemporary emission reduction measures.

SYSTEMATICS AND THE SYNECOLOGY OF AQUATIC INSECTS: PHENOLOGY AND TEMPORAL STRUCTURE OF TEMPERATE LAKE ASSEMBLAGES

1993 ◽  
Vol 125 (S165) ◽  
pp. 243-256 ◽  
Author(s):  
P.P. Harper ◽  
Louise Cloutier
Keyword(s):  
Aquatic Vegetation ◽  
Temporal Structure ◽  
Seasonal Succession ◽  
Late Summer ◽  
Open Water ◽  
Temporal Analysis ◽  
Shore Station ◽  
Near Shore ◽  
The One ◽  
Lake Systems

AbstractFour emergence series were collected from a small mesotrophic–dystrophic lake in the southern Laurentians of Québec: near shore (station A, 0.3 m, shrubs and heaths), in the littoral zone (B, 0.6 m, and C, 1 m, aquatic vegetation), and in open water (D, 6 m, no vegetation). A gradient of species richness (121–34), of numbers (4622–1120/m2), of diversity (5.62–2.42 bits), and of equitability (0.81–0.48) extended from the shore to the open water. Also recognized was a seasonal succession of early synchronized species, many of which completed a second generation by late summer, and of more dispersed summer species. This pattern was best exemplified in the shore station, whereas in deeper sites, the assemblages were increasingly less structured and dominated by fewer species. Chaoborus punctipennis, a benthic insect feeding in the water column at night, tended to predominate in the outer stations and to impose its particular seasonal dynamics on the assemblage there. Chronological clustering revealed distinctive early- and late-season assemblages in all sites. A succession of distinct and temporally structured mid-season assemblages was evident at the shore station, but this pattern was obscured in other stations because of the recurrence and dominance of the same species throughout. Though these particular patterns may be restricted to the one lake studied, this approach based on a taxonomical and temporal analysis offers promise for generalizations once it has been applied to a variety of lake systems.

Alexandrium catenella and Alexandrium minutum blooms in the Mediterranean Sea: Toward the identification of ecological niches

Harmful Algae ◽  
2008 ◽  
Vol 7 (4) ◽  
pp. 515-522 ◽  
Author(s):  
Isabel Bravo ◽  
Magda Vila ◽  
Mercedes Masó ◽  
Rosa Isabel Figueroa ◽  
Isabel Ramilo
Keyword(s):  
Mediterranean Sea ◽  
Ecological Niches ◽  
Alexandrium Minutum ◽  
Alexandrium Catenella ◽  
The Mediterranean

scholarly journals FORAMINIFERA BENTONIK KAITANNYA DENGAN KUALITAS PERAIRAN DI WILAYAH BARAT DAYA PULAU MOROTAI, MALUKU UTARA

2017 ◽  
Vol 14 (1) ◽  
Author(s):  
Amir Sidiq ◽  
Suwarno Hadisusanto ◽  
Kresna Tri Dewi
Keyword(s):  
Water Quality ◽  
Community Structure ◽  
Coral Reef ◽  
Water Depth ◽  
Diversity Index ◽  
Coral Triangle ◽  
Environmental Condition ◽  
Evenness Index ◽  
Shore Station ◽  
Near Shore

Pulau Morotai, Maluku Utara merupakan salah satu pulau yang terletak di kawasan segitiga terumbu karang  sebagai pusat kenakeragaman biota laut global. Kesehatan ekosistem terumbu karang dapat dipantau dengan menggunakan komposisi foraminifera bentonik. Maksud dan tujuan studi ini adalah untuk mengetahui struktur komunitas foraminifera bentoni terkait dengan kualitas perairan sebelah barat daya Pulau Morotai. Studi ini menggunakan enam sampel sedimen dasar laut dengan tiga kali perulangan yang diambil pada  kedalaman antara 16 dan 36 m. Hasilnya menunjukkan ada 28 spesies foraminifera bentonik, dicirikan oleh kehadiran Amphistegina dan Operculina dalam jumlah sangat melimpah. Amphistegina radiata merupakan spesies dengan densitas tertinggi di stasiun dekat pantai. Nilai indeks keanekaragaman foraminifera antara 1,49 dan 2,31 yang tergolong dalam kondisidengan tingkat keanekaragaman sedang. Indeks keseragaman umumnya lebih besar dari 0,6 yang menunjukkan lingkungan stabil. Nilai indeks FORAM (FI) berkisar dari 6,32 hingga 9,16 yang memperlihatkan  kondisi lingkungan yang kondusif bagi pertumbuhan terumbu karang. Kata kunci: struktur komunitas, foraminifera bentonik, terumbu karang, MorotaiMorotai Island, North Molucca is one of islands that is located in the Coral triangle region as the global centre of marine biodiversity.  The health of this coral ecosystem could be monitored by using benthonic foraminferal composition. The purpose of this study are re recognized community structure of benthic foraminifera related to water quality off southwest Morotai, Island. This study used six marine sediments samples with three times of replication that collected from 16 -36 m water depth. The result shows that there are 28 spesies of benthonic foraminifera characterized by occurences of Amphistegina and Operculina abundantly. Amphistegina radiata is a highest density species that is found in the near shore station. The diversity index is between 1,49 and 2,31 as moderate diversity;  evenness index generally is more than 0,6 that indicates stable environment. FORAM index (FI) is more than 4 (6,32 to 9,16) that shows of  condusif environmental condition for reef growth.Keywords: community structure, benthonic foraminifera, coral reef, Morotai

scholarly journals Characterization of the microbiomic association between tonsil and saliva isolated from Korean children subjected to tonsillectomy using 16S rRNA sequencing: a pilot study

2020 ◽  
Author(s):  
Da Hyeon Choi ◽  
Ji Won Park ◽  
Ju Kwang Choi ◽  
Kyeong Eun Lee ◽  
Won Hee Lee ◽  
...  
Keyword(s):  
16S Rrna ◽  
Microbial Communities ◽  
Diversity Index ◽  
Rank Correlation ◽  
16S Rrna Gene Sequencing ◽  
Shannon Index ◽  
Rrna Gene ◽  
Strong Positive Correlation ◽  
Korean Children ◽  
Positive Correlation

Abstract Background Oral microbes have the capacity to spread throughout the gastrointestinal system and are significantly associated with multiple diseases. Given that tonsils are located between the oral cavity and laryngoesophagus at the gateway of both alimentary and respiratory tracts, tonsillar tissue may also be affected by both oral (saliva) and alimentary tract microbiota. While several independent reports on oral microbiomes from saliva and tonsils are documented in the literature, limited studies have compared tonsil and saliva microbiota compositions. Here, we analyzed the distribution of the microbial communities in saliva and tonsils of healthy Korean children subjected to tonsillectomy.ResultsIn total, 29 study subjects were enrolled from an initial 45 participants subjected to tonsillectomy owing to hyperplasia over two years. The microbiome profiles of saliva and tonsils were established via 16S rRNA gene sequencing. Based on the Chao1 diversity index, the tonsil group showed higher richness in species, compared to the saliva group. On the other hand, the Shannon index revealed a significantly higher biodiversity value for saliva relative to tonsils. The microbial communities of the two groups were highly similar. The top 10 ranked taxa common to both groups determined based on average relative abundance were as follows: Haemophilus, Fusobacterium, Streptococcus, Veillonella, Prevotella 7, Alloprevotella, Porphyromonas, Treponema 2, Campylobacter, and Neisseria. Spearman’s rank correlation analysis conducted to elucidate interactions between the groups showed the strongest positive correlation of Treponema 2 between saliva and tonsils. Streptococcus, Veillonella, and Alloprevotella in saliva were negatively correlated with Prevotella 7 in tonsils while Prevotella 7 in saliva showed a strong positive correlation with Alloprevotella in tonsils. ConclusionsTo our knowledge, this is the first study to present a correlation between tonsil and salivary microbiomes in Korean children who have undergone tonsillectomy. Overall, strong similarities between the tonsil and saliva microbial communities are evident in terms of diversity and composition. Furthermore, the saliva microbiome is expected to significantly affect the tonsil microbiome. Based on the collective results, we propose that the identified microbes act as both intracellular and external environmental factors with a major impact on the functioning of tonsils and their primary cells.

scholarly journals Contrasting Quantitative Traits and Neutral Genetic Markers for Genetic Resource Assessment of Mesoamerican Cedrela Odorata

2005 ◽  
Vol 54 (1-6) ◽  
pp. 281-292 ◽  
Author(s):  
C. Navarro ◽  
S. Cavers ◽  
A. Pappinen ◽  
P. Tigerstedt ◽  
A. Lowe ◽  
...  
Keyword(s):  
Genetic Markers ◽  
Population Differentiation ◽  
Quantitative Traits ◽  
Balancing Selection ◽  
Atlantic Coast ◽  
Resource Assessment ◽  
Shannon Index ◽  
Strong Positive Correlation ◽  
Cedrela Odorata ◽  
Endangered Tree

Abstract We compared within-population variability and degree of population differentiation for neutral genetic markers (RAPDS) and eight quantitative traits in Central American populations of the endangered tree, Cedrela odorata. Whilst population genetic diversity for neutral markers (Shannon index) and quantitative traits (heritability, coefficient of additive genetic variation) were uncorrelated, both marker types revealed strong differentiation between populations from the Atlantic coast of Costa Rica and the rest of the species’ distribution. The degree of interpopulation differentiation was higher for RAPD markers (FST = 0.67 for the sampled Mesoamerican range) than for quantitative traits (QST = 0.30). Hence, the divergence in quantitative traits was lower than could have been achieved by genetic drift alone, suggesting that balancing selection for similar phenotypes in different populations of this species. Nevertheless, a comparison of pair-wise estimates of population differentiation in neutral genetic markers and quantitative traits revealed a strong positive correlation (r = 0.66) suggesting that, for C. odorata, neutral marker divergence could be used as a surrogate for adaptive gene divergence for conservation planning. The utility of this finding and suggested further work are discussed.

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

2019 ◽  
Vol 476 (24) ◽  
pp. 3705-3719 ◽  
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.

The Strong Positive Correlation between Factor VII Clotting Activity Using Bovine Thromboplastin and the Activated Factor VII Level

1995 ◽  
Vol 73 (03) ◽  
pp. 429-434 ◽  
Author(s):  
Kazuomi Kario ◽  
Takefumi Matsuo ◽  
Reiko Asada ◽  
Toshiyuki Sakata ◽  
Hisao Kato ◽  
...  
Keyword(s):  
Risk Factor ◽  
Bovine Brain ◽  
Factor Vii ◽  
Rabbit Brain ◽  
Strong Positive Correlation ◽  
Chromogenic Substrate ◽  
Moderate Correlation ◽  
Positive Correlation ◽  
Activated Factor Vii

SummaryWe compared factor VII clotting activity (FVIIc) assays using different thromboplastins to determine which is the most sensitive for activated FVII (FVIIa) or for FVII antigen (FVIIag). FVIIc levels were measured using thromboplastins derived from bovine brain (FVIIc Bov), human placenta (FVIIc Hum), and rabbit brain (FVIIc Rab). FVIIa levels were measured by fluorogenic assays using human soluble tissue factor (rsTF) or bovine rsTF. We also measured FVII activity by an amidolytic assay (FVIIc:am Hum) using human thromboplastin and a chromogenic substrate for thrombin. FVIIag levels were determined by ELISA. In the FVIIa assay, the reaction time obtained from using bovine rsTF was shorter than that with human rsTF, suggesting that the interaction of plasma FVIIa with bovine rsTF was stronger than with human rsTF. The plasma FVIIa levels measured using human rsTF and bovine rsTF were almost the same (r=0.947, p<0.0001). Among the three FVIIc assays, FVIIc Bov had the strongest positive correlation with the plasma FVIIa level (r=0.886, p<0.000l), but had no correlation with FVIIag. An increase of 1 ng/ml in the plasma FVIIa level yielded a 27.9% increase of FVIIc Bov. Plasma FVIIc Hum and FVIIc:am Hum showed moderate correlations with both FVIIa (r=0.520, p<0.02 and r=0.569, p<0.01, respectively) and FVIIag (r=0.438, p<0.05 and r=0.468, p<0.05, respectively). FVIIc Rab had the lowest correlation with FVIIa (r=0.367, p<0.1), but had a moderate correlation with FVIIag (r=0.436, p<0.05). After in vitro cold activation, FVIIc Bov levels increased the most and FVIIc:am levels showed the least change. These findings indicate that consideration of the thromboplastin used for assay is necessary when assessing the clinical significance of FVII activity as a cardiovascular risk factor.

Sign in / Sign up

Export Citation Format

Share Document