Abstract Professor Abby Smith grew up in New England loving the ocean, and in due course became a marine scientist. From the vantage point of nearing retirement after over 30 years in the game, she ...reflects here on where she came from, people who helped along the journey, and what she learned.
Anthropogenically-modulated reductions in pH, termed ocean acidification, could pose a major threat to the physiological performance, stocks, and biodiversity of calcifiers and may devalue their ...ecosystem services. Recent debate has focussed on the need to develop approaches to arrest the potential negative impacts of ocean acidification on ecosystems dominated by calcareous organisms. In this study, we demonstrate the role of a discrete (i.e. diffusion) boundary layer (DBL), formed at the surface of some calcifying species under slow flows, in buffering them from the corrosive effects of low pH seawater. The coralline macroalga Arthrocardia corymbosa was grown in a multifactorial experiment with two mean pH levels (8.05 'ambient' and 7.65 a worst case 'ocean acidification' scenario projected for 2100), each with two levels of seawater flow (fast and slow, i.e. DBL thin or thick). Coralline algae grown under slow flows with thick DBLs (i.e., unstirred with regular replenishment of seawater to their surface) maintained net growth and calcification at pH 7.65 whereas those in higher flows with thin DBLs had net dissolution. Growth under ambient seawater pH (8.05) was not significantly different in thin and thick DBL treatments. No other measured diagnostic (recruit sizes and numbers, photosynthetic metrics, %C, %N, %MgCO3) responded to the effects of reduced seawater pH. Thus, flow conditions that promote the formation of thick DBLs, may enhance the subsistence of calcifiers by creating localised hydrodynamic conditions where metabolic activity ameliorates the negative impacts of ocean acidification.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Coralline algae are susceptible to the changes in the seawater carbonate system associated with ocean acidification (OA). However, the coastal environments in which corallines grow are subject to ...large daily pH fluctuations which may affect their responses to OA. Here, we followed the growth and development of the juvenile coralline alga Arthrocardia corymbosa, which had recruited into experimental conditions during a prior experiment, using a novel OA laboratory culture system to simulate the pH fluctuations observed within a kelp forest. Microscopic life history stages are considered more susceptible to environmental stress than adult stages; we compared the responses of newly recruited A. corymbosa to static and fluctuating seawater pH with those of their field-collected parents. Recruits were cultivated for 16 weeks under static pH 8.05 and 7.65, representing ambient and 4× preindustrial pCO2 concentrations, respectively, and two fluctuating pH treatments of daily Formula: see text (daytime pH = 8.45, night-time pH = 7.65) and daily Formula: see text (daytime pH = 8.05, night-time pH = 7.25). Positive growth rates of new recruits were recorded in all treatments, and were highest under static pH 8.05 and lowest under fluctuating pH 7.65. This pattern was similar to the adults' response, except that adults had zero growth under fluctuating pH 7.65. The % dry weight of MgCO3 in calcite of the juveniles was reduced from 10% at pH 8.05 to 8% at pH 7.65, but there was no effect of pH fluctuation. A wide range of fleshy macroalgae and at least 6 species of benthic diatoms recruited across all experimental treatments, from cryptic spores associated with the adult A. corymbosa. There was no effect of experimental treatment on the growth of the benthic diatoms. On the community level, pH-sensitive species may survive lower pH in the presence of diatoms and fleshy macroalgae, whose high metabolic activity may raise the pH of the local microhabitat.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The effects of ocean acidification, a major anthropogenic impact on marine life, have been mainly investigated in laboratory/mesocosm experiments. We used the CO
vents at Ischia as a natural ...laboratory to study the long-term effects of ocean acidification on the sea urchin Paracentrotus lividus population resident in low-pH (7.8 ± 0.2) compared to that at two control sites (pH 8.02 ± 0.00; 8.02 ± 0.01). The novelty of the present study is the analysis of the sea urchin immune cells, the sentinels of environmental stress responses, by a wide-ranging approach, including cell morphology, biochemistry and proteomics. Immune cell proteomics showed that 311 proteins were differentially expressed in urchins across sites with a general shift towards antioxidant processes in the vent urchins. The vent urchin immune cells showed higher levels of total antioxidant capacity, up-regulation of phagosome and microsomal proteins, enzymes of ammonium metabolism, amino-acid degradation, and modulation of carbon metabolism proteins. Lipid-hydroperoxides and nitric oxide levels were not different in urchins from the different sites. No differences in the coelomic fluid pH, immune cell composition, animal respiration, nitrogen excretion and skeletal mineralogy were observed. Our results reveal the phenotypic plasticity of the immune system of sea urchins adapted to life at vent site, under conditions commensurate with near-future ocean acidification projections.
The effects of ocean acidification, a major anthropogenic impact on marine life, have been mainly investigated in laboratory/mesocosm experiments. We used the CO2 vents at Ischia as a natural ...laboratory to study the long-term effects of ocean acidification on the sea urchin Paracentrotus lividus population resident in low-pH (7.8 ± 0.2) compared to that at two control sites (pH 8.02 ± 0.00; 8.02 ± 0.01). The novelty of the present study is the analysis of the sea urchin immune cells, the sentinels of environmental stress responses, by a wide-ranging approach, including cell morphology, biochemistry and proteomics. Immune cell proteomics showed that 311 proteins were differentially expressed in urchins across sites with a general shift towards antioxidant processes in the vent urchins. The vent urchin immune cells showed higher levels of total antioxidant capacity, up-regulation of phagosome and microsomal proteins, enzymes of ammonium metabolism, amino-acid degradation, and modulation of carbon metabolism proteins. Lipid-hydroperoxides and nitric oxide levels were not different in urchins from the different sites. No differences in the coelomic fluid pH, immune cell composition, animal respiration, nitrogen excretion and skeletal mineralogy were observed. Our results reveal the phenotypic plasticity of the immune system of sea urchins adapted to life at vent site, under conditions commensurate with near-future ocean acidification projections.
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•Paracentrotus lividus living at CO2 vents was compared to those at two control sites.•Sea urchins are adapted to life at vent site by altering immune cells metabolism.•Vent animals show a rearrangement of defensive abilities and antioxidant processes.
We examined the long-term effects of near-future changes in temperature and acidification on skeletal mineralogy, thickness, and strength in the sea urchin Tripneustes gratilla reared in all ...combinations of three pH (pH 8.1, 7.8, 7.6) and three temperatures (22 °C, 25 °C, 28 °C) from the early juvenile to adult, over 146 days. As the high-magnesium calcite of the echinoderm skeleton is a biomineral form highly sensitive to acidification, and influenced by temperature, we documented the MgCO3 content of the spines, test plates, and teeth. The percentage of MgCO3 varied systematically, with more Mg2+ in the test and spines. The percentage of MgCO3 in the test and teeth, but not the spines increased with temperature. Acidification did not change the percentage MgCO3. Test thickness increased with warming and decreased at pH 7.6, with no interaction between these factors. In crushing tests live urchins mostly ruptured at sutures between the plates. The force required to crush a live urchin was reduced in animals reared in low pH conditions but increased in those reared in warm conditions, a result driven by differences in urchin size. It appears that the interactive effects of warming and acidification on the Mg2+ content and protective function of the sea urchin skeleton will play out in a complex way as global climatic change unfolds.
Bryozoans are colonial benthic marine invertebrate calcifiers, important and especially abundant and diverse in southern hemisphere shelf environments. Large heavily calcified colonies can be up to ...50 years old, but most longer-lived bryozoans are limited to 10–20 y. Many smaller species are annual. Radial extension in flat encrusting bryozoans is generally on the order of 1–5 mm/y. Erect calcified species generally grow vertically 2–15 mm/y, though articulated species such as Cellaria may reach rates of 40 mm/y. Corresponding calcification rates are generally 101–102 mg/y, but there can be an order of magnitude variation in rate among years in high-latitude bryozoans. Multi-branched bryozoans produce up to 24 g of CaCO3/y. The carbonate produced by bryozoans varies from calcite to aragonite and mixtures of both. Skeletal carbonate mineralogy of bryozoans is complex and appears to be strongly genetically controlled. Global climate change, leading to increasing water temperatures, will generally increase marine bryozoan metabolic rates, and may increase Mg in calcite. On the other hand, decreasing pH (ocean acidification) causes corrosion, changes in mineralogy, and decreased survival. This review of bryozoan growth and calcification allows a general perspective, but also reveals gaps in our knowledge which need to be addressed.
Introduction
Endoscopic eradication therapy (EET) is the preferred treatment for Barrett’s esophagus (BE)-related neoplasia patients. However, the impact of EET on critical outcomes, outside of ...clinical trials and registry data, remains scarcely studied. We aimed to assess real-world practice patterns and clinical outcomes among BE patients undergoing EET.
Methods
TriNetX is a large research network comprising linked inpatient and outpatient electronic-health record-derived data from over 80,000,000 patients. Patients with a diagnosis of BE from 2015 to 2020 were identified and included if they underwent EET during the study period. The primary outcome was the progression to EAC after index EET. Secondary outcomes included rate of esophagectomy, and all-cause mortality. All outcomes were stratified by baseline histology. The incidence of EAC and all-cause mortality were reported in person-years and adjusted for age and sex.
Results
A total of 4114 patients were analyzed. Distribution of baseline histology was as follows: NDBE (11.8%), LGD (21.4%), HGD (26.4%), EAC (20.8%), and unspecified (19.6%). The total incidence of EAC after index EET was 6.01 per 1000 person-years (PY) for the entire cohort with the highest rate in HGD patients (12.9/1000 PY). The incidence of all-cause mortality was 13.23 per 1000 PY with the highest rates in EAC patients (25.1 per 1000 PY). Rates of esophagectomy were < 1% for all grades of dysplasia.
Conclusion
The results of this study provide “real-world” data on critical outcomes for BE patients undergoing EET, demonstrating a low risk of incident EAC, all-cause mortality, and need for esophagectomy.
A retrospective chart review of 332 pediatric psoriasis patients seen at a single academic institution from 2012 to 2022 was conducted to examine the risk factors associated with palmoplantar ...psoriasis (PP), a painful and treatment‐resistant subtype of plaque psoriasis affecting hands and feet. Black patients have a 6.386‐fold increase in the odds of having PP compared to White patients and males have a 2.241‐fold increase in the odds of having PP. Black and Hispanic/Latino patients displayed a higher prevalence of nail and palm/sole involvement (p < .0001), whereas White patients exhibited more scalp involvement (p = .04). This study reveals the importance of considering the diagnosis of PP in Black male patients based on its demographic prevalence, which may in turn impact clinical care for these patients.
This paper describes the skeletal carbonate mineralogy of 156 bryozoan species collected from Scotland (sourced both from museum collections and from waters around Scotland) and collated from ...literature. This collection represents 79% of the species which inhabit Scottish waters and is a greater number and proportion of extant species than any previous regional study. The study is also of significance globally where the data augment the growing database of mineralogical analyses and offers first analyses for 26 genera and four families. Specimens were collated through a combination of field sampling and existing collections and were analysed by X-ray diffraction (XRD) and micro-XRD to determine wt% MgCO3 in calcite and wt% aragonite. Species distribution data and phylogenetic organisation were applied to understand distributional, taxonomic and phylo-mineralogical patterns. Analysis of the skeletal composition of Scottish bryozoans shows that the group is statistically different from neighbouring Arctic fauna but features a range of mineralogy comparable to other temperate regions. As has been previously reported, cyclostomes feature low Mg in calcite and very little aragonite, whereas cheilostomes show much more variability, including bimineralic species. Scotland is a highly variable region, open to biological and environmental influx from all directions, and bryozoans exhibit this in the wide range of within-species mineralogical variability they present. This plasticity in skeletal composition may be driven by a combination of environmentally-induced phenotypic variation, or physiological factors. A flexible response to environment, as manifested in a wide range of skeletal mineralogy within a species, may be one characteristic of successful invasive bryozoans.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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