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Journal of Comparative Physiology. B,... Jul 2024Southern Distinct Population Segment (sDPS) green sturgeon spawn solely in one stretch of the Sacramento River in California. Management of this spawning habitat is...
Southern Distinct Population Segment (sDPS) green sturgeon spawn solely in one stretch of the Sacramento River in California. Management of this spawning habitat is complicated by cold water temperature requirements for the conservation of winter-run Chinook salmon. This study assessed whether low incubation and rearing temperatures resulted in carryover effects across embryo to early juvenile life stages on scaling relationships in growth and metabolism in northern DPS green sturgeon used as a proxy for sDPS green sturgeon. Fish were incubated and reared at 11 °C and 15 °C, with a subset experiencing a reciprocal temperature transfer post-hatch, to assess recovery from cold incubation or to simulate a cold-water dam release which would chill rearing larvae. Growth and metabolic rate of embryos and larvae were measured to 118 days post hatch. Reciprocal temperature transfers revealed a greater effect of low temperature exposure during larval rearing rather than during egg incubation. While 11 °C eggs hatched at a smaller length, log-transformed length-weight relationships showed that these differences in developmental trajectory dissipated as individuals achieved juvenile morphology. However, considerable size-at-age differences persisted between rearing temperatures, with 15 °C fish requiring 60 days post-hatch to achieve 1 g in mass, whereas 11 °C fish required 120 days to achieve 1 g, resulting in fish of the same age at the completion of the experiment with a ca. 37-fold difference in weight. Consequently, our study suggests that cold rearing temperatures have far more consequential downstream effects than cold embryo incubation temperatures. Growth delays from 11 °C rearing temperatures would greatly increase the period of vulnerability to predation in larval green sturgeon. The scaling relationship between log-transformed whole-body metabolism and mass exhibited a steeper slope and thus an increased oxygen requirement with size in 11 °C reared fish, potentially indicating an energetically unsustainable situation. Understanding how cold temperatures affect green sturgeon ontogeny is necessary to refine our larval recruitment estimations for this threatened species.
PubMed: 38955877
DOI: 10.1007/s00360-024-01568-y -
Environmental Management Jul 2024Despite significant advancements in ichthyoplankton collection and data processing, challenges persist in the taxonomic identification of these organisms, particularly...
Despite significant advancements in ichthyoplankton collection and data processing, challenges persist in the taxonomic identification of these organisms, particularly their eggs. To overcome these challenges, a novel technique has been developed to facilitate the identification of live eggs collected directly in wild. This user-friendly technique includes the collection, processing of the material, and field incubation. Sampling must be conducted using a pelagic net towed at low speed, preferably during early evening. The material processing involves pre-sorting and sorting to remove eggs and larvae. The separated eggs, kept in an aerated bowl, can be identified based on their morphological and meristic characteristics. Unidentified eggs can be placed in plastic bags with oxygen and incubated directly in the aquatic environment for 48-72 h. After this incubation period, the hatched larvae at the yolk-sac or preflexion stage, are identified to the lowest possible taxonomic level. Depending on the study's purpose, hatched larvae and field-collected larvae can be transported to research centers for further development, released back into the natural environment, or fixed to complete the collection. The application of this technique supports management and monitoring programs by identifying spawning areas through egg identification, forming broodstock, and replenishing threatened species, thereby enhancing scientific collections of ichthyoplankton. Additionally, it reduces mortality in ichthyoplankton techniques, including endangered species. Therefore, we believe that this novel taxonomic technique for identifying live ichthyoplankton represents a paradigm shift in the monitoring, management, and conservation of fish, as well as in ecological stewardship and advances in this area of research.
PubMed: 38955870
DOI: 10.1007/s00267-024-02010-3 -
Pflugers Archiv : European Journal of... Jul 2024Cellular responses to hypoxia are crucial in various physiological and pathophysiological contexts and have thus been extensively studied. This has led to a... (Review)
Review
Cellular responses to hypoxia are crucial in various physiological and pathophysiological contexts and have thus been extensively studied. This has led to a comprehensive understanding of the transcriptional response to hypoxia, which is regulated by hypoxia-inducible factors (HIFs). However, the detailed molecular mechanisms of HIF regulation in hypoxia remain incompletely understood. In particular, there is controversy surrounding the production of mitochondrial reactive oxygen species (ROS) in hypoxia and how this affects the stabilization and activity of HIFs. This review examines this controversy and attempts to shed light on its origin. We discuss the role of physioxia versus normoxia as baseline conditions that can affect the subsequent cellular response to hypoxia and highlight the paucity of data on pericellular oxygen levels in most experiments, leading to variable levels of hypoxia that might progress to anoxia over time. We analyze the different outcomes reported in isolated mitochondria, versus intact cells or whole organisms, and evaluate the reliability of various ROS-detecting tools. Finally, we examine the cell-type and context specificity of oxygen's various effects. We conclude that while recent evidence suggests that the effect of hypoxia on ROS production is highly dependent on the cell type and the duration of exposure, efforts should be made to conduct experiments under carefully controlled, physiological microenvironmental conditions in order to rule out potential artifacts and improve reproducibility in research.
PubMed: 38955833
DOI: 10.1007/s00424-024-02986-1 -
Aging Cell Jul 2024Searching for biomarkers of senescence remains necessary and challenging. Reliable and detectable biomarkers can indicate the senescence condition of individuals, the...
Searching for biomarkers of senescence remains necessary and challenging. Reliable and detectable biomarkers can indicate the senescence condition of individuals, the need for intervention in a population, and the effectiveness of that intervention in controlling or delaying senescence progression and senescence-associated diseases. Therefore, it is of great importance to fulfill the unmet requisites of senescence biomarkers especially when faced with the growing global senescence nowadays. Here, we established that DNA G-quadruplex (G4) in mitochondrial genome was a reliable hallmark for mesenchymal senescence. Via developing a versatile and efficient mitochondrial G4 (mtG4) probe we revealed that in multiple types of senescence, including chronologically healthy senescence, progeria, and replicative senescence, mtG4 hallmarked aged mesenchymal stem cells. Furthermore, we revealed the underlying mechanisms by which accumulated mtG4, specifically within respiratory chain complex (RCC) I and IV loci, repressed mitochondrial genome transcription, finally impairing mitochondrial respiration and causing mitochondrial dysfunction. Our findings endowed researchers with the visible senescence biomarker based on mitochondrial genome and furthermore revealed the role of mtG4 in inhibiting RCC genes transcription to induce senescence-associated mitochondrial dysfunction. These findings depicted the crucial roles of mtG4 in predicting and controlling mesenchymal senescence.
PubMed: 38955799
DOI: 10.1111/acel.14265 -
Journal of the American Chemical Society Jul 2024The messenger RNA (mRNA) vaccines hold great significance in contagion prevention and cancer immunotherapy. However, safely and effectively harnessing innate immunity to...
The messenger RNA (mRNA) vaccines hold great significance in contagion prevention and cancer immunotherapy. However, safely and effectively harnessing innate immunity to stimulate robust and durable adaptive immune protection is crucial, yet challenging. In this study, we synthesized a library of stimuli-responsive bivalent ionizable lipids (srBiv iLPs) with smart molecular blocks responsive to esterase, HO, cytochrome P450, alkaline phosphatase, nitroreductase, or glutathione (GSH), aiming to leverage physiological cues to trigger fast lipid degradation, promote mRNA translation, and induce robust antitumor immunity via reactive oxygen species (ROS)-mediated boosting. After subcutaneous immunization, esterase-responsive vaccine (eBiv-mVac) was rapidly internalized and transported into the draining lymph nodes. It then underwent fast decaging and self-immolative degradation in esterase-rich antigen-presenting cells, releasing sufficient mRNA for antigen translation and massive reactive quinone methides to elevate ROS levels. This resulted in broad activation of innate immunity to boost T cell response, prompting a large number of primed antigen-specific CD8 T cells to circulate and infiltrate into tumors (>1000-fold versus unvaccinated control), thereby orchestrating innate and adaptive immunity to control tumor growth. Moreover, by further combining our vaccination strategy with immune checkpoint blockade, we demonstrated a synergism that significantly amplified the magnitude and function of antigen-specific CD8 T cells. This, in turn, caused potent systemic antitumor efficacy and prolonged survival with high complete response rate in xenograft and metastasis models. Overall, our generalized stimuli-responsive mRNA delivery platform promises a paradigm shift in the design of potent vaccines for cancer immunotherapy, as well as effective and precise carriers for gene editing, protein replacement, and cell engineering.
PubMed: 38955767
DOI: 10.1021/jacs.4c04331 -
Zhonghua Er Ke Za Zhi = Chinese Journal... Jul 2024To explore the factors affecting the prognosis of severe pediatric acute respiratory distress syndrome (ARDS) after receiving extracorporeal membrane oxygenation (ECMO)... (Observational Study)
Observational Study
To explore the factors affecting the prognosis of severe pediatric acute respiratory distress syndrome (ARDS) after receiving extracorporeal membrane oxygenation (ECMO) support. It was a multicenter prospective observational study. A total of 95 children with severe ARDS who were treated with ECMO salvage therapy from January 2018 to December 2022 in 9 pediatric ECMO centers in China were enrolled in the study. The general data, disease severity, organ function, comprehensive treatment and prognosis were recorded, and they were divided into survival group and death group according to the outcome at discharge. test, chi-square test, multivariate Logistic regression and mixed linear model were used to analyze the relationship among baseline before ECMO treatment, some important indicators (pediatric critical scores, platelet count, albumin, fibrinogen, etc) during ECMO treatment and prognosis. Among the 95 children with severe ARDS who received ECMO, 55 (58%) were males and 40 (42%) were females, aged 36.9 (0.5, 72.0) months. Twelve children (13%) were immunodeficient. Sixty-eight (72%) children were treated with venous artery (VA) mode and 27 (28%) with venous vein (VV) mode. The discharge survival rates of overall, VA, and VV mode children were 51% (48/95), 47% (32/68), and 59% (16/27), respectively. The number of immunodeficient children in the death group was higher, and there were lower pediatric critical scores, platelet count, albumin, fibrinogen and arterial oxygen partial pressure/fraction of inspired oxygen (PaO/FiO), higher ventilator driving pressure (ΔP), oxygenaion index (OI), and longer ARDS duration before ECMO (all <0.05). There were no statistically significant differences in other indicators, including age, gender, weight, and ECMO mode among different prognostic groups (all >0.05). High ΔP, high OI, low P/F, and low albumin were high-risk factors affecting prognosis(all <0.05). After further grouping, it was found that ΔP≥25 cmHO (1 cmHO=0.098 kPa), P/F≤67 mmHg (1 mmHg=0.133 kPa) and OI≥35 were the thresholds for predicting poor prognosis (<0.05). From 24 h after ECMO, there were significant differences in ΔP, P/F and OI between the dead group and the survival group (all <0.05), and the differences gradually increased with the ECMO process. The platelet level was significant from 7 days after ECMO (<0.05) and gradually expanded. Blood lactate levels showed a significant difference between the 2 groups on before and after ECMO (<0.05) and gradually increased from 24 h after ECMO. The risk factors affecting the prognosis of severe ARDS in ECMO include high ΔP, high OI, low P/F and low albumin purification therapy before ECMO. The gradual decrease of ΔP, OI and increase of P/F from 24 h of ECMO predicted a good prognosis, while the gradual increase of lactate after ECMO application showed a poor prognosis.
Topics: Humans; Extracorporeal Membrane Oxygenation; Male; Female; Prognosis; Prospective Studies; Child, Preschool; Infant; Child; Respiratory Distress Syndrome; Survival Rate; Severity of Illness Index; China; Platelet Count; Infant, Newborn
PubMed: 38955685
DOI: 10.3760/cma.j.cn112140-20231210-00422 -
Neurospine Jun 2024The therapeutic benefits of exosomes obtained from mesenchymal stem cells (MSCs) in acute spinal cord injury (SCI) have been demonstrated in recent years, but the...
OBJECTIVE
The therapeutic benefits of exosomes obtained from mesenchymal stem cells (MSCs) in acute spinal cord injury (SCI) have been demonstrated in recent years, but the precise mechanisms remain unknown. In this study, the efficacy and mechanisms of MSC-derived exosomes (MSC-Exo) in acute SCI were investigated.
METHODS
By utilizing a BV2 ferroptosis cellular model and an SCI rat model, we investigated the effects of MSC-Exo on iron death related indicators and NF-E2 related factor 2 (Nrf2)/GTP cyclolase I (GCH1)/5,6,7,8-tetrahydrobiopterin (BH4) signaling axis, as well as their therapeutic effects on SCI rats.
RESULTS
The results revealed that MSC-Exo effectively inhibited the production of ferrous iron, lipid peroxidation products malonaldehyde and reactive oxygen species, and ferroptosis-promoting factor prostaglandin-endoperoxide synthase 2. Concurrently, they upregulated ferroptosis suppressors FTH-1 (ferritin heavy chain 1), SLC7A11 (solute carrier family 7 member 11), FSP1 (ferroptosis suppressor protein 1), and GPX4 (glutathione peroxidase 4), contributing to enhanced neurological recovery in SCI rats. Further analysis showed the Nrf2/GTP/BH4 signaling pathway's critical role in suppressing ferroptosis. Additionally, MSC-Exo was found to inhibit lipopolysaccharide-induced ferroptosis in BV2 cells and SCI rats by activating the Nrf2/GCH1/BH4 axis.
CONCLUSION
In summary, the study demonstrates that MSC-Exo mitigates microglial cell ferroptosis via the Nrf2/GCH1/BH4 axis, showing potential for preserving and restoring neurological function post-SCI.
PubMed: 38955534
DOI: 10.14245/ns.2448038.019 -
Environmental Technology Jul 2024Pyrolysis is an effective process for disposing of municipal sewage sludge (SS). Plastics can affect the SS pyrolysis behaviour and pyrolysis products due to their low...
Pyrolysis is an effective process for disposing of municipal sewage sludge (SS). Plastics can affect the SS pyrolysis behaviour and pyrolysis products due to their low ash and high hydrocarbon ratio. The secondary pollutants from the pyrolysis process may also be affected. Therefore, polyethylene terephthalate (PET), a typical plastic, was chosen to investigate the release characteristics of pollutants containing nitrogen, sulphur, and chlorine via SS pyrolysis, and the changes of biochar to adsorb two typical heavy metals, Pb and Cu. The pyrolysis of PET plastics facilitates the migration of N toward solid and liquid-phase products, S and Cl to the gas-phase products via pyrolysis. Oxygenated compounds of pyrolytic volatiles decreased from 38.18% to 28.43%, concurrently promoting the formation of phenolic compounds. The co-pyrolysis improved the quality of biochar and the ability to adsorb Pb and Cu. This systematic study can provide some support for the further improvement of SS pyrolysis technology, and will also be beneficial for subsequent applications.
PubMed: 38955513
DOI: 10.1080/09593330.2024.2371079 -
Environmental Technology Jul 2024The study investigated the spatial variation of potential methane (CH) oxidation and residual carbon dioxide (CO) sequestration in biogeochemical cover (BGCC) system...
The study investigated the spatial variation of potential methane (CH) oxidation and residual carbon dioxide (CO) sequestration in biogeochemical cover (BGCC) system designed to remove CH, CO, and hydrogen sulfide (HS) from landfill gas (LFG) emissions. A 50 cm x 50 cm x 100 cm tank simulated BGCC system, comprising a biochar-amended soil (BAS) layer for CH oxidation, a basic oxygen furnace (BOF) slag layer for CO and HS sequestration, and an upper topsoil layer. Synthetic LFG was flushed through the system in five phases, with each corresponding to different compositions and flow rates. Following monitoring, the system was dismantled, and samples were extracted from different depths and locations to analyze spatial variations, focusing on moisture content (MC), organic content (OC), pH, and electrical conductivity (EC). Additionally, batch tests on selected samples from BAS and BOF slag layers were performed to assess potential CH oxidation and residual carbonation capacity. The aim of study was to evaluate the BGCC's effectiveness in LFG mitigation, however this study focused on assessing spatial variations in physico-chemical properties, CH oxidation in the BAS layer, and residual carbonation in the BOF slag layer. Findings revealed CH oxidation in the BAS layer varied between 22.4 and 277.9 µg CH/g-day, with higher rates in the upper part, and significant spatial variations at 50 cm below ground surface (bgs) compared to 85 cm bgs. The BOF slag layer showed a residual carbonation capacity of 40-49.3 g CO/kg slag, indicating non-uniform carbonation. Overall, CH oxidation and CO sequestration capacities varied spatially and with depth in the BGCC system.
PubMed: 38955503
DOI: 10.1080/09593330.2024.2372052 -
Nursing in Critical Care Jul 2024Critical patients may experience various adverse events during transportation within hospitals. Therefore, quickly evaluating and classifying patients before...
BACKGROUND
Critical patients may experience various adverse events during transportation within hospitals. Therefore, quickly evaluating and classifying patients before transporting them from the emergency department and focusing on managing high-risk patients are critical. At present, no unified classification method exists; all the current approaches are subjective.
AIMS
To ensure transportation safety, we conducted a cluster analysis of critically ill patients transferred from the emergency department to the intensive care unit.
STUDY DESIGN
Single-centre cohort study. This study was conducted at a comprehensive first-class teaching hospital in Beijing. Convenience sampling and continuous enrolment were employed. We collected data from 1 January 2019, to 31 December 2021. All patients were transferred from the emergency department to the intensive care unit, and cluster analysis was conducted using five variables.
RESULTS
A total of 584 patients were grouped into three clusters. Cluster 1 (high systolic blood pressure group) included 208 (35.6%) patients. Cluster 2 (high heart rate and low blood oxygen group) included 55 (9.4%) patients. Cluster 3 (normal group) included the remaining 321 (55%) patients. The oxygen saturation levels of all the patients were lower after transport, and the proportion of adverse events (61.8%) was the highest in Cluster 2 (p < .05).
CONCLUSIONS
This study utilized data on five important vital signs from a cluster analysis to explore possible patient classifications and provide a reference for ensuring transportation safety.
RELEVANCE TO CLINICAL PRACTICE
Before transferring patients, we should classify them and implement targeted care. Changes in blood oxygen levels in all patients should be considered, with a focus on the occurrence of adverse events during transportation among patients with high heart rates and low blood oxygen levels.
PubMed: 38955501
DOI: 10.1111/nicc.13099