scholarly journals Long Term Adaptation to Heat Stress: Shifts in the Minimum Mortality Temperature in the Netherlands

2020 ◽  
Vol 11 ◽  
Author(s):  
Mireille A. Folkerts ◽  
Peter Bröde ◽  
W. J. Wouter Botzen ◽  
Mike L. Martinius ◽  
Nicola Gerrett ◽  
...  
Keyword(s):  
Heat Stress ◽  
The Netherlands ◽  
Adaptation To Heat ◽  
Minimum Mortality Temperature

scholarly journals When enemies do not become friends: Experimental evolution of heat-stress adaptation in a vertically transmitted parasite

2020 ◽  
Author(s):  
Eike Dusi ◽  
Sascha Krenek ◽  
Thomas Petzoldt ◽  
Oliver Kaltz ◽  
Thomas U. Berendonk
Keyword(s):  
Heat Stress ◽  
Experimental Evolution ◽  
Bacterial Symbiont ◽  
Stress Adaptation ◽  
Paramecium Tetraurelia ◽  
Fitness Costs ◽  
Selective Elimination ◽  
Symbiont Transmission ◽  
Adaptation To Heat

AbstractStrict vertical (parent-to-offspring) transmission of symbionts may be associated with benevolence and mutualism, because host reproduction and symbiont transmission are linked. Nonetheless, many such symbionts do reduce host fitness costs and the factors driving their evolution are unclear. Using microcosm populations of Caedibacter taeniospiralis, a vertically transmitted bacterial symbiont of the protozoan Paramecium tetraurelia, we investigated evolutionary change under permissive conditions (26°C) and under heat stress (32°C), over 150 host generations. We found evidence for symbiont adaptation to heat stress, involving increased infection persistence and, consequently, higher rates of vertical transmission. For certain genetic backgrounds, heat-stress adaptation was associated with higher proliferation of infected lines at 26°C, suggesting cost-free evolution of super-generalists. Despite a general decrease in symbiont virulence relative to ancestral strains, infected evolved lines still showed substantial reductions (>20%) in population growth. There was no sign of a temperature-specific reduction in virulence or protection of the host against heat stress. Our results show that obligately vertically transmitted symbionts can still qualify as ‘parasites’ and evolve adaptations that do not help their hosts. Long-term infection persistence might require additional mechanisms, such as the symbiont-mediated ’killer trait’ in this system, allowing the selective elimination of uninfected individuals in the population.

scholarly journals Linking population size structure, heat stress and bleaching responses in a subtropical endemic coral

Coral Reefs ◽  
2021 ◽  
Author(s):  
Liam Lachs ◽  
Brigitte Sommer ◽  
James Cant ◽  
Jessica M. Hodge ◽  
Hamish A. Malcolm ◽  
...  
Keyword(s):  
Heat Stress ◽  
Size Structure ◽  
Temporal Trends ◽  
Early Recovery ◽  
Size Frequency Distribution ◽  
Frequency Distributions ◽  
Community Organisation ◽  
Size Frequency ◽  
Eastern Australia

AbstractAnthropocene coral reefs are faced with increasingly severe marine heatwaves and mass coral bleaching mortality events. The ensuing demographic changes to coral assemblages can have long-term impacts on reef community organisation. Thus, understanding the dynamics of subtropical scleractinian coral populations is essential to predict their recovery or extinction post-disturbance. Here we present a 10-yr demographic assessment of a subtropical endemic coral, Pocillopora aliciae (Schmidt-Roach et al. in Zootaxa 3626:576–582, 2013) from the Solitary Islands Marine Park, eastern Australia, paired with long-term temperature records. These coral populations are regularly affected by storms, undergo seasonal thermal variability, and are increasingly impacted by severe marine heatwaves. We examined the demographic processes governing the persistence of these populations using inference from size-frequency distributions based on log-transformed planar area measurements of 7196 coral colonies. Specifically, the size-frequency distribution mean, coefficient of variation, skewness, kurtosis, and coral density were applied to describe population dynamics. Generalised Linear Mixed Effects Models were used to determine temporal trends and test demographic responses to heat stress. Temporal variation in size-frequency distributions revealed various population processes, from recruitment pulses and cohort growth, to bleaching impacts and temperature dependencies. Sporadic recruitment pulses likely support population persistence, illustrated in 2010 by strong positively skewed size-frequency distributions and the highest density of juvenile corals measured during the study. Increasing mean colony size over the following 6 yr indicates further cohort growth of these recruits. Severe heat stress in 2016 resulted in mass bleaching mortality and a 51% decline in coral density. Moderate heat stress in the following years was associated with suppressed P. aliciae recruitment and a lack of early recovery, marked by an exponential decrease of juvenile density (i.e. recruitment) with increasing heat stress. Here, population reliance on sporadic recruitment and susceptibility to heat stress underpin the vulnerability of subtropical coral assemblages to climate change.

scholarly journals COVID-19: first long-term care facility outbreak in the Netherlands following cross-border introduction from Germany, March 2020

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Mitch van Hensbergen ◽  
Casper D. J. den Heijer ◽  
Petra Wolffs ◽  
Volker Hackert ◽  
Henriëtte L. G. ter Waarbeek ◽  
...  
Keyword(s):  
The Netherlands ◽  
Long Term Care ◽  
Care Facility ◽  
Control Measures ◽  
Border Region ◽  
Term Care ◽  
Term Care Facility ◽  
Long Term Care Facility ◽  
Cross Border

Abstract Background The Dutch province of Limburg borders the German district of Heinsberg, which had a large cluster of COVID-19 cases linked to local carnival activities before any cases were reported in the Netherlands. However, Heinsberg was not included as an area reporting local or community transmission per the national case definition at the time. In early March, two residents from a long-term care facility (LTCF) in Sittard, a Dutch town located in close vicinity to the district of Heinsberg, tested positive for COVID-19. In this study we aimed to determine whether cross-border introduction of the virus took place by analysing the LTCF outbreak in Sittard, both epidemiologically and microbiologically. Methods Surveys and semi-structured oral interviews were conducted with all present LTCF residents by health care workers during regular points of care for information on new or unusual signs and symptoms of disease. Both throat and nasopharyngeal swabs were taken from residents suspect of COVID-19, based on regional criteria, for the detection of SARS-CoV-2 by Real-time Polymerase Chain Reaction. Additionally, whole genome sequencing was performed using a SARS-CoV-2 specific amplicon-based Nanopore sequencing approach. Moreover, twelve random residents were sampled for possible asymptomatic infections. Results Out of 99 residents, 46 got tested for COVID-19. Out of the 46 tested residents, nineteen (41%) tested positive for COVID-19, including 3 asymptomatic residents. CT-values for asymptomatic residents seemed higher compared to symptomatic residents. Eleven samples were sequenced, along with three random samples from COVID-19 patients hospitalized in the regional hospital at the time of the LTCF outbreak. All samples were linked to COVID-19 cases from the cross-border region of Heinsberg, Germany. Conclusions Sequencing combined with epidemiological data was able to virtually prove cross-border transmission at the start of the Dutch COVID-19 epidemic. Our results highlight the need for cross-border collaboration and adjustment of national policy to emerging region-specific needs along borders in order to establish coordinated implementation of infection control measures to limit the spread of COVID-19.

Strategies for climate change adaptation: lessons learnt from long-term planning in the Netherlands and Bangladesh

2021 ◽  
pp. 1-28
Author(s):  
Jos van Alphen ◽  
Jaap de Heer ◽  
Ellen Minkman
Keyword(s):  
Climate Change ◽  
The Netherlands ◽  
Climate Change Adaptation ◽  
Lessons Learnt

Short- and long-term dynamics of the physiological and behavioral response to heat stress and thymol supplementation in Japanese quail

2021 ◽  
pp. 102876
Author(s):  
Maria Emilia Fernandez ◽  
Maria Carla Labaque ◽  
Gabriel Orso ◽  
Raúl Hector Marin ◽  
Jackelyn Melissa Kembro
Keyword(s):  
Heat Stress ◽  
Japanese Quail ◽  
Behavioral Response ◽  
Short And Long Term

An ER–Golgi Tethering Factor SLOH4/MIP3 Is Involved in Long-term Heat Tolerance of Arabidopsis

2020 ◽  
Author(s):  
Kazuho Isono ◽  
Ryo Tsukimoto ◽  
Satoshi Iuchi ◽  
Akihisa Shinozawa ◽  
Izumi Yotsui ◽  
...  
Keyword(s):  
Heat Stress ◽  
Heat Tolerance ◽  
Secretory Proteins ◽  
Wild Type ◽  
Additional Function ◽  
Transcript Levels ◽  
Unfolded Protein ◽  
In The Wild ◽  
Protein Response

Abstract Plants are often exposed not only to short-term (S-) heat stress but also to diurnal long-term (L-) heat stress over several consecutive days. To reveal the mechanisms underlying L-heat stress tolerance, we here used a forward genetic screening for sensitive to long-term heat (sloh) mutants and isolated sloh4. The mutant was hypersensitive to L- but not S-heat stress. The causal gene of sloh4 was identical to MIP3 encoding a member of the MAIGO2 (MAG2) tethering complex, which is composed of the MAG2, MIP1, MIP2, and MIP3 subunits and is localized at the endoplasmic reticulum (ER) membrane. Although sloh4/mip3 was hypersensitive to L-heat stress, the sensitivity of the mag2-3 and mip1–1 mutants was similar to that of the wild type. Under L-heat stress, the ER stress and the following unfolded protein response (UPR) were more pronounced in sloh4 than in the wild type. Transcript levels of bZIP60-regulated UPR genes were strongly increased in sloh4 under L-heat stress. Two processes known to be mediated by INOSITOL REQUIRING ENZYME1 (IRE1)—accumulation of the spliced bZIP60 transcript and a decrease in the transcript levels of PR4 and PRX34, encoding secretory proteins—were observed in sloh4 in response to L-heat stress. These findings suggest that misfolded proteins generated in sloh4 under L-heat stress may be recognized by IRE1 but not bZIP28, resulting in initiation of the UPR via activated bZIP60. Therefore, it would be possible that only MIP3 in MAG2 complex has an additional function in L-heat tolerance, which is not related to the ER–Golgi vesicle tethering.

Immunolocalization of antioxidant enzymes in testis of rams submitted to long-term heat stress

Zygote ◽  
2019 ◽  
Vol 27 (6) ◽  
pp. 432-435
Author(s):  
Thais Rose dos Santos Hamilton ◽  
Gabriela Esteves Duarte ◽  
José Antonio Visintin ◽  
Mayra Elena Ortiz D’Ávila Assumpção
Keyword(s):  
Oxidative Stress ◽  
Superoxide Dismutase ◽  
Antioxidant Enzymes ◽  
Heat Stress ◽  
Glutathione Peroxidase ◽  
Cell Types ◽  
Treated Group ◽  
Oxidative Balance ◽  
Testicular Cells

SummaryLong-term heat stress (HS) induced by testicular insulation generates oxidative stress (OS) on the testicular environment; consequently activating antioxidant enzymes such as superoxide dismutase (SOD), glutathione reductase (GR) and glutathione peroxidase (GPx). The aim of this work was to immunolocalize antioxidant enzymes present in different cells within the seminiferous tubule when rams were submitted to HS. Rams were divided into control (n = 6) and treated group (n = 6), comprising rams subjected to testicular insulation for 240 h. After the testicular insulation period, rams were subjected to orchiectomy. Testicular fragments were submitted to immunohistochemistry for staining against SOD, GR and GPx enzymes. We observed immunolocalization of GPx in more cell types of the testis after HS and when compared with other enzymes. In conclusion, GPx is the main antioxidant enzyme identified in testicular cells in an attempt to maintain oxidative balance when HS occurs.

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