scholarly journals Thermally tolerant symbionts may explain Caribbean octocoral resilience to heat stress

Coral Reefs ◽  
2021 ◽  
Author(s):  
Jessie Pelosi ◽  
Katherine M. Eaton ◽  
Samantha Mychajliw ◽  
Casey P. terHorst ◽  
Mary Alice Coffroth

AbstractCoral reef ecosystems are under threat from the frequent and severe impacts of anthropogenic climate change, particularly rising sea surface temperatures. The effects of thermal stress may be ameliorated by adaptation and/or acclimation of the host, symbiont, or holobiont (host + symbiont) to increased temperatures. We examined the role of the symbiont in promoting thermal tolerance of the holobiont, using Antillogorgia bipinnata (octocoral host) and Breviolum antillogorgium (symbiont) as a model system. We identified five distinct genotypes of B. antillogorgium from symbiont populations isolated from Antillogorgia colonies in the Florida Keys. Three symbiont genotypes were cultured and maintained at 26 °C (ambient historical temperature), and two were cultured and maintained at 30 °C (elevated historical temperature) for 2 yrs. We analyzed the growth rate and carrying capacity of each symbiont genotype at both ambient and elevated temperatures in culture (in vitro). All genotypes grew well at both temperatures, indicating that thermal tolerance exists among these B. antillogorgium cultures. However, a history of long-term growth at 30 °C did not yield better performance for B. antillogorgium at 30 °C (as compared to 26 °C), suggesting that prior culturing at the elevated temperature did not result in increased thermal tolerance. We then inoculated juvenile A. bipinnata polyps with each of the five symbiont genotypes and reared these polyps at both ambient and elevated temperatures (in hospite experiment). All genotypes established symbioses with polyps in both temperature treatments. Survivorship of polyps at 30 °C was significantly lower than survivorship at 26 °C, but all treatments had surviving polyps at 56 d post-infection. Our results suggest broad thermal tolerance in B. antillogorgium, which may play a part in the increased resilience of Caribbean octocorals during heat stress events.

2020 ◽  
Author(s):  
Jessie Pelosi ◽  
Katherine M. Eaton ◽  
Samantha Mychajliw ◽  
Casey P. terHorst ◽  
Mary Alice Coffroth

AbstractCoral reef ecosystems are under threat from the frequent and severe impacts of anthropogenic climate change, particularly rising sea surface temperatures. The effects of thermal stress may be ameliorated by adaptation and/or acclimation of the host, symbiont, or holobiont (host + symbiont) to increased temperatures. We examined the role of the symbiont in promoting thermal tolerance of the holobiont, using Antillogorgia bipinnata (octocoral host) and Breviolum antillogorgium (symbiont) as a model system. We identified five distinct genotypes of B. antillogorgium from symbiont populations isolated from A. bipinnata colonies. Three symbiont genotypes were maintained at 26°C (ambient historical temperature) and two were maintained at 30°C (elevated historical temperature) for two years. We analyzed the in vitro growth rate and carrying capacity of each genotype at both ambient and elevated temperatures. All genotypes grew well at both temperature treatments, indicating thermal tolerance among these B. antillogorgium genotypes. We also inoculated juvenile A. bipinnata polyps with each of the five symbiont genotypes, and reared these polyps at both ambient and elevated temperatures. All genotypes were able to infect polyps at both temperature treatments. Survivorship of polyps at 30°C was significantly lower than survivorship at 26°C, but all treatments had surviving polyps at 56 days post-infection, suggestive of broad-scale thermal tolerance in this system. The widespread thermal tolerance observed in B. antillogorgium may play a part in the increased resilience of Caribbean octocorals during heat stress events.


2018 ◽  
Vol 8 (3) ◽  
pp. 36-41
Author(s):  
Diep Do Thi Hong ◽  
Duong Le Phuoc ◽  
Hoai Nguyen Thi ◽  
Serra Pier Andrea ◽  
Rocchitta Gaia

Background: The first biosensor was constructed more than fifty years ago. It was composed of the biorecognition element and transducer. The first-generation enzyme biosensors play important role in monitoring neurotransmitter and determine small quantities of substances in complex matrices of the samples Glutamate is important biochemicals involved in energetic metabolism and neurotransmission. Therefore, biosensors requires the development a new approach exhibiting high sensibility, good reproducibility and longterm stability. The first-generation enzyme biosensors play important role in monitoring neurotransmitter and determine small quantities of substances in complex matrices of the samples. The aims of this work: To find out which concentration of polyethylenimine (PEI) exhibiting the most high sensibility, good reproducibility and long-term stability. Methods: We designed and developed glutamate biosensor using different concentration of PEI ranging from 0% to 5% at Day 1 and Day 8. Results: After Glutamate biosensors in-vitro characterization, several PEI concentrations, ranging from 0.5% to 1% seem to be the best in terms of VMAX, the KM; while PEI content ranging from 0.5% to 1% resulted stable, PEI 1% displayed an excellent stability. Conclusions: In the result, PEI 1% perfomed high sensibility, good stability and blocking interference. Furthermore, we expect to develop and characterize an implantable biosensor capable of detecting glutamate, glucose in vivo. Key words: Glutamate biosensors, PEi (Polyethylenimine) enhances glutamate oxidase, glutamate oxidase biosensors


2015 ◽  
Vol 93 (8) ◽  
pp. 641-648 ◽  
Author(s):  
Azza Ramadan ◽  
Mark D. Wheatcroft ◽  
Adrian Quan ◽  
Krishna K. Singh ◽  
Fina Lovren ◽  
...  

Autophagy regulates cellular homeostasis and integrates the cellular pro-survival machinery. We investigated the role of autophagy in the natural history of murine abdominal aortic aneurysms (AAA). ApoE−/− mice were implanted with saline- or angiotensin II (Ang-II)-filled miniosmotic pumps then treated with either the autophagy inhibitor chloroquine (CQ; 50 mg·(kg body mass)–1·day–1, by intraperitoneal injection) or saline. Ang-II-elicited aneurysmal expansion of the suprarenal aorta coupled with thrombus formation were apparent 8 weeks later. CQ had no impact on the incidence (50% for Ang-II compared with 46.2% for Ang-II + CQ; P = NS) and categorical distribution of aneurysms. The markedly reduced survival rate observed with Ang-II (57.1% for Ang-II compared with 100% for saline; P < 0.05) was unaffected by CQ (61.5% for Ang-II + CQ; P = NS compared with Ang-II). CQ did not affect the mean maximum suprarenal aortic diameter (1.91 ± 0.19 mm for Ang-II compared with 1.97 ± 0.21 mm for Ang-II + CQ; P = NS). Elastin fragmentation, collagen accumulation, and smooth muscle attrition, which were higher in Ang-II-treated mice, were unaffected by CQ treatment. Long-term CQ administration does not affect the natural history and prognosis of experimental AAA, suggesting that global loss of autophagy is unlikely to be a causal factor in the development of aortic aneurysms. Manipulation of autophagy as a mechanism to reduce AAA may need re-evaluation.


Author(s):  
Paweł Bukowski ◽  
Filip Novokmet

AbstractWe construct the first consistent series on the long-term distribution of income in Poland by combining tax, household survey and national accounts data. We document a U-shaped evolution of inequalities from the end of the nineteenth century until today: (1) inequality was high before WWII; (2) abruptly fell after the introduction of communism in 1947 and stagnated at low levels during the whole communist period; (3) experienced a sharp rise with the return to capitalism in 1989. We find that official survey-based measures strongly under-estimate the rise in inequality since 1989. Our results highlight the prominent role of capital income in driving the U-shaped evolution of top income shares. The unique inequality history of Poland speaks to the central role of institutions and policies in shaping inequality in the long run.


Author(s):  
Christophe Sand

New Caledonia is the southern-most archipelago of Melanesia. Its unique geological diversity, as part of the old Gondwana plate, has led to specific pedological and floral environments that have, since first human settlement, influenced the ways Pacific Islanders have occupied and used the landscape. This essay presents some of the key periods of the nearly 3,000 years of pre-colonial human settlement. After having presented a short history of archaeological research in New Caledonia, the essay focuses first on the Lapita foundation, which raises questions of long-term contacts and cultural change. The second part details the unique specificities developed during the “Traditional Kanak Cultural Complex,” during the millennium predating first European contact, as well as highlighting the massive changes brought by the introduction of new diseases, in the decades before the colonial settlement era. This leads to questions about archaeological history and the role of archaeology in the present decolonizing context.


1993 ◽  
Vol 264 (2) ◽  
pp. C457-C463 ◽  
Author(s):  
I. Dorup ◽  
T. Clausen

In young rats fed a Mg(2+)-deficient diet for 3 wk, Mg2+ and K+ contents in soleus and extensor digitorum longus muscles were significantly reduced and closely correlated. In isolated soleus muscles, Mg2+ depletion induced an even more pronounced loss of K+, and Mg2+ and K+ contents were correlated over a wide range (r = 0.95, P < 0.001). Extracellular Mg2+ (0-1.2 mM) caused no change in total or ouabain-suppressible 86Rb influx. After long-term incubation in Ca(2+)-Mg(2+)-free buffer with EDTA and EGTA, cellular Mg2+ and K+ contents were reduced by 35 and 15%, respectively, without any reduction in ATP and total or ouabain-suppressible 86Rb influx. In Mg(2+)-depleted muscles 42K efflux was increased by up to 42%, and repletion with Mg2+ produced a graded decrease. We conclude that Mg2+ and K+ contents are closely correlated in muscles Mg2+ depleted in vivo or in vitro and that neither extracellular nor moderate intracellular Mg2+ depletion affects total or Na(+)-K+ pump-mediated K+ influx. The reduced K+ content may rather be related to increased K+ efflux from the muscles.


2020 ◽  
Vol 17 (2) ◽  
pp. 54
Author(s):  
Anindita L. ◽  
Aris Aji K. ◽  
Arcadia Sulistijo J.

Hypertension presents an increase in blood pressure following the oral manifestations, such as gingival enlargement. A 42-year-old woman came to the General Sudirman University Dental and Oral Hospital complaining of enlarged front gums seven years ago. The patient had a history of hypertension and regularly consumed drugs, amlodipine 5 mg. Extraoral examination revealed no lymphadenopathy and no swelling of the head and neck area. Intraoral examination revealed a gingival enlargement involving the papilla to the gingival margin present on the entire upper and lower labial gingival surface. The patient's diagnosis was gingival enlargement caused by gingival enlargement due to the use of amlodipine. Gingival enlargement has been noted with long-term or high-dose amlodipine use. The mechanism of amlodipine in causing gingival enlargement is through the role of fibroblasts with abnormal susceptibility to the drug, resulting in increased levels of protein synthesis, especially collagen. The role of pro-inflammatory cytokines occurs through an increase in interleukin-1β (IL-1β) and IL-6 in the inflamed gingival tissue due to the gingival fibrogenic response to drugs. Therapies were DHE and scaling and root planning as phase I in periodontal treatment. Plaque elimination is vital to reduce gingival inflammation that may occur. Substitution of the drug amlodipine may be needed if there is no improvement. Based on case reports, hypertension patients who took amlodipine could have gingival enlargement. The therapy given was plaque elimination in the form of DHE and Scaling and regular check-ups with the dentist.


2021 ◽  
Vol 17 (1) ◽  
pp. e1009153
Author(s):  
Bindu S. Mayi ◽  
Jillian A. Leibowitz ◽  
Arden T. Woods ◽  
Katherine A. Ammon ◽  
Alphonse E. Liu ◽  
...  

Neuropilin-1 (NRP-1), a member of a family of signaling proteins, was shown to serve as an entry factor and potentiate SARS Coronavirus 2 (SARS-CoV-2) infectivity in vitro. This cell surface receptor with its disseminated expression is important in angiogenesis, tumor progression, viral entry, axonal guidance, and immune function. NRP-1 is implicated in several aspects of a SARS-CoV-2 infection including possible spread through the olfactory bulb and into the central nervous system and increased NRP-1 RNA expression in lungs of severe Coronavirus Disease 2019 (COVID-19). Up-regulation of NRP-1 protein in diabetic kidney cells hint at its importance in a population at risk of severe COVID-19. Involvement of NRP-1 in immune function is compelling, given the role of an exaggerated immune response in disease severity and deaths due to COVID-19. NRP-1 has been suggested to be an immune checkpoint of T cell memory. It is unknown whether involvement and up-regulation of NRP-1 in COVID-19 may translate into disease outcome and long-term consequences, including possible immune dysfunction. It is prudent to further research NRP-1 and its possibility of serving as a therapeutic target in SARS-CoV-2 infections. We anticipate that widespread expression, abundance in the respiratory and olfactory epithelium, and the functionalities of NRP-1 factor into the multiple systemic effects of COVID-19 and challenges we face in management of disease and potential long-term sequelae.


2021 ◽  
Vol 21 ◽  
Author(s):  
Xinwei Huang ◽  
Xiuqing Li ◽  
Lijuan Yang ◽  
Pengfei Wang ◽  
Jingyuan Yan ◽  
...  

Aims: We aim to define parameters affecting the safety and long-term transgene expression of attenuated HSV-1 vectors and optimize the expression cassettes to achieve robust and sustained expression in CNS. Background: Engineered, attenuated Herpes simplex virus (HSV) vectors are promising vehicles for gene delivery to the peripheral and central nervous systems. The virus latent promoter (LAP) is commonly used to drive exogenous gene expression; however, parameters affecting the safety and long-term transgene expression of attenuated HSV-1 vectors have not been fully understood. Objective: This study aimed to construct attenuated HSV-1 vectors using the CRISPR-Cas9 system and examine the influence of transgene cassette construction and insertion site on transgene expression and vector safety. Method: In this study, we used a CRISPR-Cas9 system to accurately and efficiently edit attenuated HSV-1 strain 1716, and constructed two series of recombinant virus LMR and LMRx with different sets of gene cassettes insertion in Exon1(LAP2) and 2.0 kb intron downstream of LAP, respectively. The transgene expression and viral gene transcriptional kinetics were compared in in-vitro cell lines. The reporter gene expression and safety profiles of each vector were further evaluated in the mouse hippocampus gene transduction model. Result: The in-vitro cell line analysis indicated that the insertion of a gene expression cassette would disrupt virus gene transcription. Mouse hippocampus transducing analysis suggested that complete expression cassette insertion at 2.0 kb intron could achieve robust and longtime gene expression than the other constructs. Recombinants with gene expression cassettes lacked Poly (A), which induced significant neuronal inflammation due to persistent viral antigen expression and microglia activation. Conclusion: Our results indicated that the integrity of LAT transcripts was not necessary for the establishment of long-term latent expression. Exogenous strong promoters (like cBh promoter) could remain active during latency when placed in Exon1 or 2.0 Kb Intron of LAT locus, although their transcriptional activity declined with time. Consistent with previous research, the foreign gene expression would last much longer when the gene cassette was located downstream of Exon1, which suggested a role of LAP2 in maintaining promoter activity during latency. Besides, over-transcription of the downstream part of LAT may induce continuous activation of the attenuated vectors, suggesting an important role of LAT in maintaining viral reactivation potential.


Author(s):  
Elena A. Schneider

The introduction sketches the contours of the British six-week invasion and eleven-month occupation of Havana in 1762–1763, a major event in the history of the Atlantic world. It describes the framework of the book, “an event history” that relies on multiple, overlapping temporal and spatial frames in order to tie together many different strands of history, historical actors, perspectives, and scales. In giving a long-term history of the causes, central dynamics, and enduring consequences of this event, the book focuses on the crucial role of the slave trade and people of African descent. The actions of people of African descent and imperial rivalry over the slave trade shaped both the invasion and occupation of Havana in ways yet to be fully understood. The rest of the book explores the painful irony that black soldiers’ brave service in Havana during the British siege helped lead to new Spanish policies that endorsed and expanded slavery and the slave trade.


Sign in / Sign up

Export Citation Format

Share Document