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At least 19 recordsLinked to original sources
PubMed2026

Genome-wide epigenomic atlas and multi-omics responses of Eriocheir sinensis to natural extreme heat.

BACKGROUND: Global climate warming has led to increasingly frequent and prolonged extreme summer heat events, posing severe environmental challenges to aquaculture systems. Extreme summer heat can disrupt the performance of pond-cultured ectotherms. The Chinese mitten crab (Eriocheir sinensis) is an economically important freshwater crustacean, but coordinated molecular differences following contrasting natural summers remain incompletely characterized. RESULTS: We performed a comprehensive multi-omics analysis integrating meteorological monitoring, mRNA/lncRNA transcriptomics, small-RNA profiling of miRNAs, DNA methylomics, and LC-MS metabolomics in E. sinensis populations collected from Yancheng, China, between 2020 and 2024. Across the ten farms, survival was significantly lower in 2024, whereas yield and the proportion of large individuals showed nonsignificant downward trends. Gene-set analyses showed negative enrichment of cellular heat-response, protein-folding, oxidative-phosphorylation, and mitochondrial ATP-production terms in the 2024 cohort at the time of sampling. The integrated transcript annotation contained 72,240 lncRNAs and 63,833 mRNAs, and CpG was the predominant methylation context. Differential methylation analysis identified 73 regions and 185 cytosines, with hypomethylated events predominating within the significant subset. Metabolomic profiles differed between annual cohorts and mapped to carbohydrate, lipid, and amino-acid pathways. Cross-omics integration prioritized eight candidate genes-ADCY9, UNC79, UBN1, IFT52, ACO2, LOC126986070, LOC127001126, and LOC126997895-and qPCR reproduced the reported directions of expression for selected RNAs. CONCLUSION: This study provides the first integrative multi-omics framework for understanding chronic heat adaptation in E. sinensis. By linking transcriptomic, epigenomic, and metabolic remodeling, we elucidate the molecular mechanisms underlying energy imbalance, epigenetic reprogramming, and immune dysregulation during prolonged thermal stress. These findings offer valuable insights and genomic resources for breeding heat-tolerant crab strains and improving aquaculture resilience under ongoing climate change.

DNA methylation↗
PubMed1978

Age and sex difference in response to short exposure to extreme dry heat.

Sixty volunteers, 33 males and 27 females (18-63 yr), were divided according to age and sex. They were exposed for 10 min to extreme dry heat: 80-90 degrees C dry bulb temperature and 3-4% relative humidity. Their rectal temperature, skin temperature at eight different points, weight, and heart rate were recorded prior to and immediately following the exposure. A mean rise of only 0.5 degrees C in rectal temperature was recorded following exposure as compared to a mean rise of 5.2 degrees C in mean weighted skin temperature (MWST). Female subjects showed a significantly higher rise in MWST than the male subjects. Similarly, a significantly higher rise in MWST was observed in elderly male subjects as compared to the youngest male group (P less than 0.05). The differences in MWST possibly resulted from differences in mean skin blood flow causing differences in skin conductance. Large individual variation in heat response was recorded in rectal temperature, as well as in weighted skin temperatures. The increase in skin temperature during the first 10 min of exposure to extreme dry heat may serve as an indicator for heat tolerance time, and may help predicting heatstroke susceptible individuals.

Adaptation, Physiological↗
PubMed2025

Molecular mechanisms and breeding strategies for heat tolerance in vegetable crops under global warming.

Extreme heat driven by climate change poses a catastrophic threat to global vegetable production, undermining nutritional security because of the heightened physiological sensitivity and succulent tissues of these crops. This review synthesizes the multistage impacts of heat stress across critical developmental phases-from germination to reproduction-emphasizing morphological impairments (such as leaf wilting and floral abortion) and physiological disruptions (including photosynthetic inhibition and oxidative damage). We systematically dissect thermotolerance mechanisms in vegetables, highlighting transcriptional reprogramming by HSFs, WRKY, and NAC transcription factors; chaperone-mediated proteostasis via HSPs; epigenetic remodeling; Ca2+-ROS signaling pathways; and the role of phase separation dynamics. Importantly, we propose six strategic pathways to develop heat-resilient vegetables: harnessing natural variation through pan-genome-driven allele mining; employing biotechnological interventions such as CRISPR-mediated editing and synthetic promoters; engineering multistress tolerance by targeting conserved 'core response' pathways; exploiting epigenetic memory to achieve transgenerational resilience; optimizing source-sink dynamics with ''Climate-Responsive Carbon Optimization; and applying plant growth regulators and nanotechnology to enhance thermotolerance. Together, these strategies chart a clear roadmap for climate-smart vegetable breeding and call for interdisciplinary collaboration to translate molecular discoveries into practical breeding approaches for sustainable food systems under escalating thermal extremes.

Journal Article↗
PubMed1979

Differentiation of vaccine strains and field isolates of pseudorabies (Aujeszky's disease) virus: thermal sensitivity and rabbit virulence markers.

Eleven cloned North American pseudorabies virus (PRV) strains and the European vaccine strains K and BUK were characterized by their thermal sensitivity and rabbit virulence markers. Heat sensitivity of the strains and isolates ranged from the highly heat resistant strain K, to the extremely heat labile strain BUK and isolate Be. The inactivation curves of each virus were transformed to the logarithmic scale and their standardized slopes and predicted virus survival values at 30 minutes were plotted against each other. The result was a distribution of points that represented a thermal sensitivity spectrum (TSS). Virus strains were subsequently categorized into 1 of 3 groups according to their position in the TSS. Viruses were also categorized into three groups according to their ability to clinically infect rabbits, their ability to produce pruritus and the time required to kill. When individual strains were described according to their marker profiles, 5 of 9 possible marker combinations were revealed. The 2 vaccine strains were each described by separate profiles. Virulent field isolates were characterized by 1 of 3 different profiles.

Animals↗
PubMed2026

Heat stress in cereal crops: reproductive development and grain filling.

Increasingly frequent extreme heat events threaten cereal production and food security under a changing climate. The reproductive-to-grain formation continuum of cereals is particularly vulnerable to elevated temperatures, as heat stress disrupts developmental processes from inflorescence formation and fertilization to grain filling and quality establishment. These disruptions reduce reproductive success, impair yield formation, and compromise grain quality. A comprehensive understanding of the developmental, physiological, molecular, and genetic basis of cereal heat tolerance is therefore essential for developing climate-adapted crops. This review summarizes recent advances in understanding heat stress during cereal reproduction and grain filling across major cereal crops. We first discuss how heat stress affects sequential developmental processes, including inflorescence development, gametophyte development, flowering and pollination, fertilization, and grain filling. We then integrate emerging evidence on cross-cutting mechanisms that connect stage-specific heat responses, focusing on hormonal and redox homeostasis, carbohydrate metabolism and source-sink coordination, proteostasis and endomembrane organization, and genome stability and multilayered gene regulation. Finally, we summarize the genetic basis of cereal heat tolerance by highlighting genetic determinants, favorable alleles, and their potential applications in breeding. We further discuss current bottlenecks and future opportunities for breeding heat-tolerant cereals.

Cereals↗
PubMed1978

Preliminary characterization of a temperature-sensitive mutant of Moloney murine leukemia virus that produces particles at the restrictive temperature.

The isolation and preliminary characterization of a new temperature-sensitive mutant of Moloney murine leukemia virus, designated ts7, are reported. The infectivity of ts7, determined by a focus-forming unit assay, was reduced at least 100-fold when the virus was assayed at the nonpermissive temperature (39 degrees C) as compared with assay at the permissive temperature (34 degrees C). However, several lines of evidence indicated that the diminution of ts7 titer at 39 degrees C is not due to its inability to form virus particles at that temperature. The supernatant from ts7-infected cells grown at 39 degrees C showed significant infectivity when assayed at 34 degrees C; only small reductions in reverse transcriptase activity and fusion ability were observed when compared with supernatant from 34 degrees C ts7-infected cultures. That particles are produced at the nonpermissive temperature was confirmed by transmission electron microscopy of the supernatant from ts7-infected cells at 39 degrees C and by transmission electron microscope observations of mature particles trapped in the intercellular spaces of pelleted thin cell section. A possible explanation for the productivity at 39 degrees C of particles that are infectious at 34 degrees C but not at 39 degrees C is that the virus is heat labile at the nonpermissive temperature. Consistent with this hypothesis is the extreme heat lability of virus harvested at 34 degrees C. Such virus, when incubated at 39 degrees C, has a half-life one-sixth that of identical virus incubated at 34 degrees C, or that of wild-type virus at either temperature.

Cell Fusion↗
PubMed1976

Effects of Tumor-like assay conditions, lonizing radiation, and hyperthermia on immune lysis of tumor cells by cytotoxic T-lymphocytes.

Cytotoxic T-lymphocytes (CTL's) harvested from mixed splenic lymphocyte cultures (DBA/2 + C57BL) were tested for their ability to lyse allogeneic P815 mastocytoma cells under various tumor-like assay conditions, with or without previous exposure to ionizing radiation or hyperthermia (43 degrees). There was little or no decrease of immune cytolysis when CTL's were assayed by 51Cr release under tumor-like conditions (plateau-phase target cells, low pH, or anoxia) or after irradiation, but cytolytic activity was greatly reduced when CTL's were exposed to heat; 45 min of hyperthermic treatment decreased activity by greater than or equal to 99% while reducing the apparent cell viability (as indicated by trypan blue exclusion) by only 30%. When the P815 target cells rather than the CTL's were exposed to heat their susceptibility to immune lysis was not affected even after treatment times that were lethal to the tumor cells. Despite the dissimilar heat sensitivities of CTL and P815 cells, the dose-response curves for inhibition of protein synthesis by heat, as indicated by [3H]leucine incorporation, were similar for both cell types: neither the depression of protein synthesis in heated CTL's nor the decreased cytolytic ability of these cells was reversed within 3 hr. When irradiated or heated P815 cells were incubated with CTL's, the resulting survival curves were always additive, indicating that neither irradiation nor heat treatment affected the susceptibility of the tumor cells to immune attack. The extreme heat sensitivity of cytotoxic T-lymphocytes raises important questions about the possible effects of hyperthermic treatment on the immune competence of cancer patients.

Animals↗
PubMed2026

From population to individual: advocating personalised digital tools for heat-health early warning in a changing climate.

Escalating heat extremes under climate change are imposing substantial health burdens, with 2023 and 2024 consecutively breaking global temperature records. Mounting evidence suggests that heatwaves elevate the risks of hospitalisation and mortality across multiple disease categories, including ischaemic heart disease, stroke, chronic obstructive pulmonary disease, and acute kidney injury. Nonetheless, most existing heat-health warning systems remain primarily reliant on population-level predictions, and considering individual differences and disease-specific considerations when defining warning levels would benefit the effectiveness of early prevention for high-risk groups. In this Viewpoint, which is based on the framework of precision public health-delivering the right intervention to the right population at the right time-we propose a framework for personalised digital heat-health early warning tools comprising three dimensions: individualised, risk-stratified prediction models that generate tiered early warnings; personalised health prompts coupled with theory-informed behavioural interventions; and adaptive, equity-oriented alert delivery mechanisms tailored to diverse populations. Such tools have the potential to bridge precision disease prevention and climate adaptation, thereby helping to mitigate heat exposure risks and disease burdens, particularly among high-risk populations. Future implementation research will be essential to address substantial challenges related to feasibility, validation, and equity.

Journal Article↗
PubMed1977

Purification of a protein inhibitor of adenosine 3':5'-monophosphate-dependent protein kinase from bovine myocardium by a non-denaturing procedure.

The activities of adenosine 3':5'-monophosphate (cyclic AMP)-dependent protein kinase may be partially controlled by a ubiquitous acidic heat-stable protein which inhibits the phosphotransferase reaction by interaction with the catalytic subunit of protein kinase (Walsh, D.A. et al. (1971), J. Biol. Chem. 246, 1977-1985). Since reported purification of this inhibitor involved subjecting tissue extracts to denaturing conditions, its existence under physiological conditions remained uncertain. A protein inhibitor, molecular weight 22,500, has been isolated from bovine myocardium by methods that do not include exposure to extreme heat or acid precipitation. The activity of this acidic protein is destroyed by exposure to trypsin and is unaffected by treatment with neuraminidase, RNAse or DNAse.

Animals↗
PubMed2025

De novo transcriptome assembly and gene expression analysis of Cnidium officinale under high-temperature conditions.

BACKGROUND: The medicinal plant Cnidium officinale (CO) is widespread in Northeast Asia and vulnerable to heat stress. The naturally occurring composition of pharmacological ingredients of CO results in overall physiological consequences; therefore, it is crucial to have a comprehensive understanding of metabolic response to ambient heat in terms of acclimation to estimate how much CO is exposed to threatening environmental conditions. RESULTS: Transcriptome analysis is critical for understanding the consequences of long-term physiological adaptation of CO to abiotic stress. However, transcriptome analysis on this species, particularly under prolonged stress conditions, has remained limited. We employed a temperature gradient tunnel (TGT) to subject CO to high-temperature exposure for four months, enabling us to observe the cumulative effects of heat and assess its acclimation mechanisms. In the absence of genome sequencing data, we performed de novo transcriptome assembly and compared DEGs from temperature treatment plots of a TGT and a growth chamber (GC). Since interpreting transcriptomic data can be complex, we employed a sequential analytical approach, including DEG clustering, GO enrichment, KEGG pathway mapping, miRNA-target gene analysis, and multiple rounds of RNA sequencing validation. DEGs were classified into two categories: genes exhibiting significant fold changes and genes showing significant count changes rather than fold changes. Then, we analyzed the functional roles of DEGs to determine which pathways respond to ambient and stressful high temperatures and validated the findings through cross-comparison with GC. Additionally, we conducted miRNA analysis to investigate post-transcriptional regulation under high temperatures. CO grown under higher ambient temperatures exhibited slight upregulation of pathways related to protein stability and turnover, ABA biosynthesis, and energy production, such as photosynthesis and oxidative phosphorylation. However, under extreme heat stress, most metabolic pathways were downregulated except for those involved in transcription, translation, oxidative phosphorylation and the biosynthesis of cutin, suberin, and wax. CONCLUSION: This study demonstrated that proper clustering of genes based on expression levels and fold changes in two different experimental conditions, along with pathway mapping, may provide a comprehensive understanding of CO's response to heat stress. These insights could contribute to future research on heat tolerance and crop improvement.

Gene Expression Profiling↗
PubMed1978

Purification and some properties of three forms of glucoamylase from a Rhizopus species.

1. Three forms of glucoamylase [EC 3.2.1.3] were simultaneously purified from a Rhizopus species by (NH4)2SO4 fractionation and successive chromatographies on Sephadex G-75, DEAE-Sephadex, and CM-Sephadex, and were finally separated from each other by means of recycling chromatography on Bio-Gel P-150. The purification achieved was 3--4 fold from crude extract with respect to each glucoamylase; the yields of the three glucoamylases, designated as Gluc1, Gluc2, and Gluc3 in order of content, were 39, 7, and 0.4%, respectively. All the purified enzymes were homogeneous in polyacrylamide gel electrophoresis, isoelectric focusing, and ultracentrifugation. 2. The three glucoamylases were glycoproteins differing in both amino acid composition and carbohydrate content, but showed a common antigenicity in immunodiffusion. The molecular weights of Gluc1, Gluc2, and Gluc3 were estimated to be 74,000, 58,600, and 61,400, respectively, by sedimentation equilibrium and these values were verified by SDS-polyacrylamide gel electrophoresis. The specific activities of the three enzymes toward starch were in the opposite order to their molecular weights. 3. The three glucoamylases had the same broad pH optima in the range pH 4.5--5.0 and shared a common susceptibility to inactivation by heat, extreme pH, and such divalent cations as Hg2+, Pb2+, and Mn2+, indicating close similarity in enzymatic properties.

Amino Acids↗
PubMed1979

Production of a bacteriocine-like substance by group-A streptococci of M-type 4 and T-pattern 4.

A unique and characteristic bacteriocine-like inhibitor elaborated by M-type 4, T-pattern 4, group-A streptococci was isolated and partially purified. This inhibitor was found to be produced optimally in Todd-Hewitt broth; after extraction and concentration, was shown to be protein in nature, and to have a m.w. of c. 8000. It was extremely heat stable and acid tolerant, but was quickly inactivated in alkaline conditions. It could be demonstrated in cell-bound form, but 99.5% was found in culture supernates. It was specifically adsorbed by viable sensitive cells, and its mode of action was bacteristatic.

Antigens, Bacterial↗
PubMed1978

Receptors for glucocorticoids in the lens epithelium of the calf.

The calf lens epithelium contains a specific cytoplasmic receptor for glucocorticoids. This binding protein has a high affinity for dexamethasone (average dissociation constant, 8 x 10(-9) mole per liter), a low capacity (average, 550 femtomoles per milligram of protein), extreme heat sensitivity, and exhibits a pattern of competition similar to that of glucocorticoid receptors in other tissues. This provides direct biochemical evidence that these tissues may function as a target organ for glucocorticoids.

Animals↗
PubMed1978

Specific 5 alpha-dihydrotestosterone receptors in human gingiva.

The cytoplasm of normal human male and female gingiva contains a receptor capable of specifically binding 5 alpha-dihydrotestosterone (DHT). This binding has a high affinity for DHT (Kd, approximately 2.2 x 10-9 M) and a low capacity (approximately 190 fmol/mg protein). The binding is extremely heat sensitive and exhibits a pattern of competition similar to that obtained with DHT receptors from other target tissues. The demonstration of a specific DHT receptor in human gingiva provides the first direct biochemical evidence that this tissue may function as a target organ for androgens. There was no correlation between the Kd in normal tissue and gingival hyperplasia or between the Kd or number of binding sites and the age or sex of the patient. However, there sites and the age or sex of the patient. However, there was a significant difference (P less than 0.0005) between the amount of DHT-binding sites per mg protein in normal tissue as compared to gingival hyperplasia (drugs or pregnancy).

Adolescent↗
PubMed2026

Thermophilic bacteria of the Arabian Gulf and their emerging biotechnological applications: current insights and future prospects.

Thermophilic bacteria represent a powerful class of extremophiles whose ability to thrive at elevated temperatures makes them indispensable to modern biotechnology. The Arabian Gulf characterized by extreme heat, geothermal systems, hot springs, oil reservoirs, and hypersaline habitats hosts a rich yet understudied reservoir of these organisms. This review consolidates current insights into the diversity, ecological niches, and biotechnological relevance of thermophilic bacteria isolated from the region. Dominant genera such as Bacillus, Geobacillus, Thermus, Anoxybacillus, and Brevibacillus exhibit remarkable physiological and molecular strategies that enable survival under intense thermal, saline, and pH stress. Their capacity to produce thermostable enzymes, including proteases, amylases, lipases, cellulases, and DNA polymerases, positions them as high-value contributors to sectors spanning bioenergy, pharmaceuticals, food processing, agriculture, and environmental remediation. Beyond enzyme production, emerging applications such as antimicrobial compound discovery, hydrocarbon bioremediation, wastewater treatment, and sustainable bioprocessing highlight the region's untapped biotechnological potential. However, systematic exploration remains limited, hindered by sparse isolation efforts, incomplete physiological profiling, and a lack of genomic and omics-driven studies. The review underscores the need for integrated approaches that merge classical microbiology with advanced molecular and systems-level tools. Collectively, thermophilic bacteria from the Arabian Gulf constitute a promising yet underutilized biological resource poised to drive sustainable industrial innovation and environmental solutions.

Arabian Gulf↗
PubMed1979

Characterization of liver-type alkaline phosphatase from human gastric carcinoma cells (KMK-2) in vitro.

Alkaline phosphatase was extracted from human gastric carcinoma cells (KMK-2) under long-term culture, and its biochemical and biological properties were investigated. The enzyme was extremely heat labile and was inhibited significantly by L-homoarginine, but only slightly by L-phenylalanine, so that it was classified as a liver-type alkaline phosphatase. Comparative studies with liver and early placental alkaline phosphatases revealed that the enzymes all showed a similar extent of inhibition by amino acids, heat stability, immunological character, molecular, and other biochemical properties. However, KMK-2 alkaline phosphatase was more similar to early placental enzyme in electrophoretic and gel filtration pattern. This liver-type alkaline phosphatase was found ultrastructurally on microvilli of KMK-2 cells, but not on the lateral structurally on microvilli of KMK-2 cells, but not on the lateral surface with interdigitating folds. Prednisolone markedly decreased the content of the present isozyme. Although the present phenotype was stable during long-term culture in regard to the isozyme properties, the original cancer cells from which the cell line had been derived were L-phenylalanine sensitive and moderately L-homoarginine sensitive. This indicated that phenotypic change occurred on cultivation of cancer cells in vitro.

Alkaline Phosphatase↗
PubMed1977

Specific glucocorticoid receptor in the iris--ciliary body of the rabbit.

The cytoplasm of the iris--ciliary body of the rabbit contains a receptor capable of specifically binding dexamethasone. This binding protein has a high affinity for dexamethasone (average KD = 2.0 X 10(-8) M), a low capacity (average 4.8 X 10(-13) mol of steroid bound per milligram of protein), and extreme heat sensitivity; it exhibits a pattern of competition virtually identical to that obtained with glucocorticoid receptors from other tissues and shows characteristic physicochemical behavior in various salt concentrations. The demonstration of a specific dexamethasone receptor in the iris--ciliary body provides the first direct biochemical evidence that these tissues may function as a target organ for glucocorticoids.

Animals↗