An assessment of the biodiversity and bioremediation potential of distromatic Ulva spp (Chlorophyta) in the Great Bay Estuarine System of New Hampshire and Maine, USA

Eutrophication of coastal ecosystems is a global problem, and algae have become an important resource for bioremediation. The goals of this study were (1) to assess the biodiversity of Ulva spp. in the Great Bay Estuarine System (GBES) of New Hampshire and Maine, and (2) to assess which Ulva populations are most appropriate for bioremediation by determining if environmental nutrient history and/or taxonomie differences affect ammonium uptake. Molecular analysis of the internal transcribed spacer nrDNA regions of Ulva spp. revealed four distinct distromatic taxa: Ulva lactuca Linnaeus, Ulva rigida C. Agardh, Ulva compressa Linnaeus, and U. pertusa Kjellman. The latter three are new reports for New Hampshire. Infra- and interspecific comparisons revealed that nutrient history influences substrate affinity, whereas taxonomy influences uptake rate. Consequently, there is a clear need for reassessment of global Ulva populations, and both nutrient history and taxonomy should be considered when using Ulva for bioremediation

Macroalgal Performance and Competition under Elevated CO2

Since the industrial revolution, atmospheric carbon dioxide (CO2) concentrations have been increasing, and the surface waters of the global oceans have absorbed 30% of the anthropogenic CO2 released into the atmosphere. A higher CO2 concentration in surface ocean waters shifts the carbon chemistry, resulting in higher concentrations of bicarbonate ions (HCO3-) and protons (H ) and lower concentrations of carbonate ions (CO32-). Such a shift in ocean carbon chemistry decreases the pH and the saturation state of the seawater with respect to CO32- thereby making the precipitation of CaCO3 less kinetically favorable. These changes in ocean chemistry termed ocean acidification) are expected to have negative impacts on marine calcifying organisms, which deposit CaCO3 in the form of aragonite, calcite and high-magnesium calcite into their shells and skeletons. Because calcifying marine primary producers are very important to the carbon cycle and for rocky shore habitat structure and stability, investigating how they will respond to future oceanic CO2 levels is a relevant and important topic of research. Therefore, two calcifying marine macroalgae were chosen as the central organisms for investigation in this thesis. I investigated the physiological responses of the temperate calcifying coralline rhodophyte alga Corallina officinalis (L.) and the tropical calcifying chlorophyte alga Halimeda opuntia (L.) J. V. Lamouroux to elevated CO2 concentrations which are expected to occur by the end of this century. Furthermore, the effect of elevated CO2 on the competitive interactions between these two calcifiers and their noncalcifying counterparts was investigated in order to predict how macroalgal communities will respond to future surface ocean CO2 levels in both temperate and tropical environments. Because CO2 concentrations are increasing in surface ocean in parallel with other abiotic stressors, I also chose to investigate the response of H. opuntia to the combined effect of elevated CO2 and inorganic nutrients, which replicates a likely scenario for the condition of some eutrophied tropical coral reefs at the end of this century. The studies carried out during this thesis revealed that there are differences in the physiological responses of calcifying macroalgae to elevated CO2, but similar patterns of competitive interactions between calcifiers and noncalcifiers occur under elevated CO2 regardless of species and latitude. I found that the temperate coralline alga C. officinalis was highly sensitive to elevated CO2, as shown by lower growth and 3 photosynthetic rates and less calcified cell walls than under normal conditions. On the other hand, the tropical calcifying chlorophyte alga H. opuntia was only moderately sensitive to elevated CO2 concentrations, as this species had lower growth rates but maintained normal calcification rates and increased electron transport rates. Enzyme activity (external carbonic anhydrase and in situ nitrate reductase) in both species was affected by CO2 indicating that external carbonic anhydrase plays an important role in calcification by regulating the speciation of inorganic carbon, and that nitrogen assimilation in these species is affected by elevated CO2. The effect of CO2 on energy balance in these two species is also discussed. The different calcification mechanisms utilized by these two species is likely to account for some of the observed differences in physiological responses, and is discussed in detail below. While these two species showed different susceptibilities to elevated CO2 in isolation, they both showed similar sensitivity to overgrowth and outcompetition by noncalcifying algae when grown with their natural communities under elevated CO2 conditions. This trend was amplified under conditions of inorganic nutrients. The results of this thesis indicate that calcifying macroalgae show differences in their susceptibility to ocean acidification, but regardless of their sensitivity in isolation, both temperate and tropical species are likely to be outcompeted by noncalcifying macroalgae under elevated CO2 conditions. Tropical systems are especially susceptible to a shift in community composition (from calcifier- to noncalcifier-dominated) when eutrophication and ocean acidification occur simultaneously

Editorial: Coralline algae: Past, present, and future perspectives

Following the success of the Frontiers in Marine Science Research Topic on “Coralline Algae: Globally Distributed Ecosystem Engineers,” the Research Topic on “Coralline Algae: Past, Present and Future Perspectives” was launched to extend the opportunity for publishing further knowledge about these diverse ecosystem engineers across a broader time scale. In this Research Topic, an additional nine original research articles have been published, strengthening our understanding of coralline algae past, present, and future, including their biology, physiology and ecology. From reconstructing coralline algal assemblages during the Paleocene/Eocene thermal maximum, to understanding current trophodynamics and benthic-pelagic coupling in rhodolith beds, to assessing the adaptability of coralline algae to future warming, the original research articles in this Research Topic cover a time frame of 55.6 million years and span across an Atlantic biogeographical range from Brazil to the high Arctic.1521610info:eu-repo/semantics/publishedVersio

State of knowledge regarding the potential of macroalgae cultivation in providing climate-related and other ecosystem services

Macroalgae (or seaweed) aquaculture can potentially provide many ecosystem services, including climate change mitigation, coastal protection, preservation of biodiversity and improvement of water quality. Nevertheless, there are still many constraints and knowledge gaps that need to be overcome, as well as potential negative impacts or scale-dependent effects that need to be considered, before macroalgae cultivation in Europe can be scaled up successfully and sustainably. To investigate these uncertainties, the Expert Working Group (EWG) on Macroalgae was established. Its role was to determine the state of knowledge regarding the potential of macroalgae culture in providing climate-related and other ecosystem services (ES) and to identify specific knowledge gaps that must be addressed before harvesting this potential. The methodological framework combined a multiple expert consultation with Delphi process and a Quick Scoping Review (QSR). To analyse the outcome of both approaches, the EWG classified the findings under the categories Political, Environmental, Social, Technical, Economic and Legal (PESTEL approach) and categorised the ES based on the CICES 5.1 classification. Although representative stakeholders from many different disciplines were contacted, the majority of responses to the Delphi process were from representatives of academia or research. While the results of each method differed in many ways, both methods identified the following top six ecosystem services provided by seaweed cultivation: i) provisioning food, ii) provisioning hydrocolloids and feed, iii) regulating water quality, iv) provisioning habitats, v) provisioning of nurseries and vi) regulating climate. Diverse technological knowledge gaps were identified by both methods at all scales of the macroalgae cultivation process, followed by economic and environmental knowledge gaps depending on the method used. Based on suggestions from the expert respondents in the Delphi process, there is a clear need for an European-wide strategy for reducing risks for seaweed producers, providing clear standards and guidelines for obtaining permits, and providing financial support to improve technological innovation, that will ensure consistent quality. Legal (e.g., safety regulations), economic (e.g., lack of demand for seaweeds in many countries) and technological (e.g., production at large scale) constraints represented almost 70% of the total responses in the Delphi process, whereas environmental and technical constraints were more dominant in the literature. The most commonly identified potential negative impacts of macroalgae cultivation both among the expert responses and the reviewed articles were unknown environmental impacts, e.g. to deep sea, benthic and pelagic ecosystems. The present study provides an assessment of the state of knowledge regarding ES provided by seaweed cultivation and identifies the associated knowledge gaps, constraints and potential negative impacts. One of the main hurdles recognised by the EWG was the understanding of ES themselves by the different stakeholders, as well as the issue of scale. Studies providing clear evidence of ES provided by seaweed cultivation and/or valorisation of these services were lacking in the literature, and some aspects, like cultural impact etc. were missing in the responses to the questionnaires during the Delphi process. The issue of scale and scaling-up was omnipresent both in assessing the ES provided by seaweed cultivation and in identifying knowledge gaps, constraints and potential negative impacts. For example, the ES provided will depend on the scale of cultivation, the main technological knowledge gaps were often related to scale of cultivation. Likewise at a large scale of operations, there could be multiple associated potential side effects, which need to be further investigated. Based on the outcomes of this investigation, we provide an outlook with open questions that need to be answered to support the sustainable scaling-up of seaweed cultivation in Europe

Sex specific associations in genome wide association analysis of renal cell carcinoma.

Renal cell carcinoma (RCC) has an undisputed genetic component and a stable 2:1 male to female sex ratio in its incidence across populations, suggesting possible sexual dimorphism in its genetic susceptibility. We conducted the first sex-specific genome-wide association analysis of RCC for men (3227 cases, 4916 controls) and women (1992 cases, 3095 controls) of European ancestry from two RCC genome-wide scans and replicated the top findings using an additional series of men (2261 cases, 5852 controls) and women (1399 cases, 1575 controls) from two independent cohorts of European origin. Our study confirmed sex-specific associations for two known RCC risk loci at 14q24.2 (DPF3) and 2p21(EPAS1). We also identified two additional suggestive male-specific loci at 6q24.3 (SAMD5, male odds ratio (ORmale) = 0.83 [95% CI = 0.78-0.89], Pmale = 1.71 × 10-8 compared with female odds ratio (ORfemale) = 0.98 [95% CI = 0.90-1.07], Pfemale = 0.68) and 12q23.3 (intergenic, ORmale = 0.75 [95% CI = 0.68-0.83], Pmale = 1.59 × 10-8 compared with ORfemale = 0.93 [95% CI = 0.82-1.06], Pfemale = 0.21) that attained genome-wide significance in the joint meta-analysis. Herein, we provide evidence of sex-specific associations in RCC genetic susceptibility and advocate the necessity of larger genetic and genomic studies to unravel the endogenous causes of sex bias in sexually dimorphic traits and diseases like RCC

Genetic Variants Related to Longer Telomere Length are Associated with Increased Risk of Renal Cell Carcinoma.

BACKGROUND: Relative telomere length in peripheral blood leukocytes has been evaluated as a potential biomarker for renal cell carcinoma (RCC) risk in several studies, with conflicting findings. OBJECTIVE: We performed an analysis of genetic variants associated with leukocyte telomere length to assess the relationship between telomere length and RCC risk using Mendelian randomization, an approach unaffected by biases from temporal variability and reverse causation that might have affected earlier investigations. DESIGN, SETTING, AND PARTICIPANTS: Genotypes from nine telomere length-associated variants for 10 784 cases and 20 406 cancer-free controls from six genome-wide association studies (GWAS) of RCC were aggregated into a weighted genetic risk score (GRS) predictive of leukocyte telomere length. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Odds ratios (ORs) relating the GRS and RCC risk were computed in individual GWAS datasets and combined by meta-analysis. RESULTS AND LIMITATIONS: Longer genetically inferred telomere length was associated with an increased risk of RCC (OR=2.07 per predicted kilobase increase, 95% confidence interval [CI]:=1.70-2.53, p0.5) with GWAS-identified RCC risk variants (rs10936599 and rs9420907) from the telomere length GRS; despite this exclusion, a statistically significant association between the GRS and RCC risk persisted (OR=1.73, 95% CI=1.36-2.21, p<0.0001). Exploratory analyses for individual histologic subtypes suggested comparable associations with the telomere length GRS for clear cell (N=5573, OR=1.93, 95% CI=1.50-2.49, p<0.0001), papillary (N=573, OR=1.96, 95% CI=1.01-3.81, p=0.046), and chromophobe RCC (N=203, OR=2.37, 95% CI=0.78-7.17, p=0.13). CONCLUSIONS: Our investigation adds to the growing body of evidence indicating some aspect of longer telomere length is important for RCC risk. PATIENT SUMMARY: Telomeres are segments of DNA at chromosome ends that maintain chromosomal stability. Our study investigated the relationship between genetic variants associated with telomere length and renal cell carcinoma risk. We found evidence suggesting individuals with inherited predisposition to longer telomere length are at increased risk of developing renal cell carcinoma

The influence of obesity-related factors in the etiology of renal cell carcinoma-A mendelian randomization study.

BACKGROUND: Several obesity-related factors have been associated with renal cell carcinoma (RCC), but it is unclear which individual factors directly influence risk. We addressed this question using genetic markers as proxies for putative risk factors and evaluated their relation to RCC risk in a mendelian randomization (MR) framework. This methodology limits bias due to confounding and is not affected by reverse causation. METHODS AND FINDINGS: Genetic markers associated with obesity measures, blood pressure, lipids, type 2 diabetes, insulin, and glucose were initially identified as instrumental variables, and their association with RCC risk was subsequently evaluated in a genome-wide association study (GWAS) of 10,784 RCC patients and 20,406 control participants in a 2-sample MR framework. The effect on RCC risk was estimated by calculating odds ratios (ORSD) for a standard deviation (SD) increment in each risk factor. The MR analysis indicated that higher body mass index increases the risk of RCC (ORSD: 1.56, 95% confidence interval [CI] 1.44-1.70), with comparable results for waist-to-hip ratio (ORSD: 1.63, 95% CI 1.40-1.90) and body fat percentage (ORSD: 1.66, 95% CI 1.44-1.90). This analysis further indicated that higher fasting insulin (ORSD: 1.82, 95% CI 1.30-2.55) and diastolic blood pressure (DBP; ORSD: 1.28, 95% CI 1.11-1.47), but not systolic blood pressure (ORSD: 0.98, 95% CI 0.84-1.14), increase the risk for RCC. No association with RCC risk was seen for lipids, overall type 2 diabetes, or fasting glucose. CONCLUSIONS: This study provides novel evidence for an etiological role of insulin in RCC, as well as confirmatory evidence that obesity and DBP influence RCC risk

Anpassungsleistung und Wettbewerb von Makroalgen unter erhöhten CO2-Bedingungen

Since the industrial revolution, atmospheric carbon dioxide (CO2) concentrations have been increasing, and the surface waters of the global oceans have absorbed 30% of the anthropogenic CO2 released into the atmosphere. A higher CO2 concentration in surface ocean waters shifts the carbon chemistry, resulting in higher concentrations of bicarbonate ions (HCO3-) and protons (H ) and lower concentrations of carbonate ions (CO32-). Such a shift in ocean carbon chemistry decreases the pH and the saturation state of the seawater with respect to CO32- thereby making the precipitation of CaCO3 less kinetically favorable. These changes in ocean chemistry termed ocean acidification) are expected to have negative impacts on marine calcifying organisms, which deposit CaCO3 in the form of aragonite, calcite and high-magnesium calcite into their shells and skeletons. Because calcifying marine primary producers are very important to the carbon cycle and for rocky shore habitat structure and stability, investigating how they will respond to future oceanic CO2 levels is a relevant and important topic of research. Therefore, two calcifying marine macroalgae were chosen as the central organisms for investigation in this thesis. I investigated the physiological responses of the temperate calcifying coralline rhodophyte alga Corallina officinalis (L.) and the tropical calcifying chlorophyte alga Halimeda opuntia (L.) J. V. Lamouroux to elevated CO2 concentrations which are expected to occur by the end of this century. Furthermore, the effect of elevated CO2 on the competitive interactions between these two calcifiers and their noncalcifying counterparts was investigated in order to predict how macroalgal communities will respond to future surface ocean CO2 levels in both temperate and tropical environments. Because CO2 concentrations are increasing in surface ocean in parallel with other abiotic stressors, I also chose to investigate the response of H. opuntia to the combined effect of elevated CO2 and inorganic nutrients, which replicates a likely scenario for the condition of some eutrophied tropical coral reefs at the end of this century. The studies carried out during this thesis revealed that there are differences in the physiological responses of calcifying macroalgae to elevated CO2, but similar patterns of competitive interactions between calcifiers and noncalcifiers occur under elevated CO2 regardless of species and latitude. I found that the temperate coralline alga C. officinalis was highly sensitive to elevated CO2, as shown by lower growth and 3 photosynthetic rates and less calcified cell walls than under normal conditions. On the other hand, the tropical calcifying chlorophyte alga H. opuntia was only moderately sensitive to elevated CO2 concentrations, as this species had lower growth rates but maintained normal calcification rates and increased electron transport rates. Enzyme activity (external carbonic anhydrase and in situ nitrate reductase) in both species was affected by CO2 indicating that external carbonic anhydrase plays an important role in calcification by regulating the speciation of inorganic carbon, and that nitrogen assimilation in these species is affected by elevated CO2. The effect of CO2 on energy balance in these two species is also discussed. The different calcification mechanisms utilized by these two species is likely to account for some of the observed differences in physiological responses, and is discussed in detail below. While these two species showed different susceptibilities to elevated CO2 in isolation, they both showed similar sensitivity to overgrowth and outcompetition by noncalcifying algae when grown with their natural communities under elevated CO2 conditions. This trend was amplified under conditions of inorganic nutrients. The results of this thesis indicate that calcifying macroalgae show differences in their susceptibility to ocean acidification, but regardless of their sensitivity in isolation, both temperate and tropical species are likely to be outcompeted by noncalcifying macroalgae under elevated CO2 conditions. Tropical systems are especially susceptible to a shift in community composition (from calcifier- to noncalcifier-dominated) when eutrophication and ocean acidification occur simultaneously

State of knowledge regarding the potential of macroalgae cultivation in providing climate-related and other ecosystem services : a report of the Eklipse Expert Working Group on Macroalgae cultivation and Ecosystem Services

Macroalgae (or seaweed) aquaculture can potentially provide many ecosystem services, including climate change mitigation, coastal protection, preservation of biodiversity and improvement of water quality. Nevertheless, there are still many constraints and knowledge gaps that need to be overcome, as well as potential negative impacts or scale-dependent effects that need to be considered, before macroalgae cultivation in Europe can be scaled up successfully and sustainably. To investigate these uncertainties, the Expert Working Group (EWG) on Macroalgae was established. Its role was to determine the state of knowledge regarding the potential of macroalgae culture in providing climate-related and other ecosystem services (ES) and to identify specific knowledge gaps that must be addressed before harvesting this potential

Sex specific associations in genome wide association analysis of renal cell carcinoma

International audienceRenal cell carcinoma (RCC) has an undisputed genetic component and a stable 2:1 male to female sex ratio in its incidence across populations, suggesting possible sexual dimorphism in its genetic susceptibility. We conducted the first sex-specific genome-wide association analysis of RCC for men (3227 cases, 4916 controls) and women (1992 cases, 3095 controls) of European ancestry from two RCC genome-wide scans and replicated the top findings using an additional series of men (2261 cases, 5852 controls) and women (1399 cases, 1575 controls) from two independent cohorts of European origin. Our study confirmed sex-specific associations for two known RCC risk loci at 14q24.2 (DPF3) and 2p21(EPAS1). We also identified two additional suggestive male-specific loci at 6q24.3 (SAMD5, male odds ratio (ORmale) = 0.83 [95% CI = 0.78-0.89], Pmale = 1.71 × 10−8 compared with female odds ratio (ORfemale) = 0.98 [95% CI = 0.90–1.07], Pfemale = 0.68) and 12q23.3 (intergenic, ORmale = 0.75 [95% CI = 0.68-0.83], Pmale = 1.59 × 10−8 compared with ORfemale = 0.93 [95% CI = 0.82–1.06], Pfemale = 0.21) that attained genome-wide significance in the joint meta-analysis. Herein, we provide evidence of sex-specific associations in RCC genetic susceptibility and advocate the necessity of larger genetic and genomic studies to unravel the endogenous causes of sex bias in sexually dimorphic traits and diseases like RCC