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At least 19 recordsLinked to original sources
PubMed2026

Assessing the genetic potential of a milk mid-infrared prediction of heat stress response in dairy cows using a temperature-humidity index-independent approach.

Selection for heat tolerance remains challenging due to the difficulty of accessing reliable phenotypes at large scale. An alternative could be established using mid-infrared spectra, which are collected routinely through milk recording, and have already shown their value as proxies for a variety of phenotypes that are costly or difficult to measure. Recently, a first prediction of heat stress response in dairy cows based solely on milk mid-infrared spectra was developed. This prediction was obtained using models calibrated on surface body temperature and milk composition variations. Its potential as a detection tool was explored, but no genetic analyses has been performed. On this basis, the objectives of this study were to estimate the heritability of the predicted heat stress response, assess its genetic correlations with traits from the Walloon official genetic evaluation, and identify genomic regions associated with heat tolerance through a GWAS, all without using temperature-humidity index (THI) information. The estimated heritability (0.10) was low but sufficient to enable genetic selection and consistent with expectations for a heat stress-related trait. Also as expected, an antagonistic relationship between heat tolerance and milk production was observed, but its extent was notably reduced compared with traditional approaches. In addition, genetic correlations with other traits were neutral (fat yield) or favorable (protein yield, SCS, fertility, longevity). Concerning the GWAS, genomic regions and candidate genes previously associated with the response to heat stress were highlighted, as well as others related to energy balance maintenance. Overall, these results support the relevance of the prediction for the heat stress response as a new phenotype for heat tolerance selection that does not require any THI information. They also reinforce the importance of energy balance for dairy cows to cope with heat stress.

Journal Article↗
PubMed2026

Self-healing materials for food packaging: Design principles, activation mechanisms and implications for food safety.

Self-healing materials (SHMs), originally developed to restore mechanical integrity, have recently attracted growing interest in food packaging. By autonomously repairing physical damage, SHMs help preserve packaging integrity, barrier performance, food safety, and shelf-life during storage and transportation. This review summarizes recent advances in the design principles, activation mechanisms, material systems and food packaging applications of SHMs. Key healing strategies, including microencapsulation, dynamic covalent bond exchange, reversible non-covalent interactions and responsiveness to external stimuli such as temperature, pH, and humidity, are discussed. Representative material systems, including biopolymer-based films, hydrogels, nanocomposites, and stimuli-responsive polymers are evaluated with respect to their relevance to packaging animal-derived foods, fruits, and vegetables. Performance evaluation methods, sustainability implications, and food-contact safety concerns are addressed. Despite promising healing efficiency and mechanical resilience, challenges remain regarding production cost, food-grade safety, migration risks, trigger compatibility and stability under fluctuating environmental conditions. Future research should focus on scalable manufacturing, standardized evaluation protocols, repeated damage-healing safety assessment, regulatory compliance, and integration with intelligent packaging technologies.

Food Packaging↗
PubMed2026

Balancing growth and immunity of potato by humidity-dependent expression of a late blight resistance gene.

Inducible expression of resistance genes is an effective approach to balance plant growth and immunity, thus facilitating the development of disease-resistant crop cultivars. While pathogen-responsive and immunity-related promoters have been adopted for this purpose, alternative design strategies remain to be explored. High relative humidity (RH) has been recognized as a crucial permissive environmental condition for the occurrence of devastating plant diseases including tomato and potato late blight. Here, we identified humidity-activated cis-regulatory elements (HAEs) in Solanum lycopersicum through an integrative analysis of transcriptomics and chromatin accessibility data. Sequence homology-inferred HAEs in S. tuberosum can predict humidity-elicited changes in downstream gene expression. Transgenic S. tuberosum lines expressing a late blight resistance gene driven by an artificial humidity-inducible promoter containing a natural S. tuberosum HAE were generated. These transgenic lines exhibited comparable late blight resistance levels to the lines overexpressing the same resistance gene in controlled zoospore inoculation bioassays, while avoiding growth suppression and tuber yield penalties in common garden experiments. Our findings highlight the importance of plant cis-regulatory elements in the transcriptional responses to high RH and provide a proof-of-concept for a humidity-inducible environment-responsive resistance gene deployment strategy to engineer disease-resistant crop cultivars without compromising growth and yield.

Phytophthora infestans↗
PubMed1977

Effect of combined heat and radiation on microbial destruction.

A series of experiments at several levels of relative humidity and radiation dose rates was carried out using spores of Bacillus subtilis var. niger to evaluate the effect of heat alone, radiation alone, and a combination of heat and radiation. Combined heat and radiation treatment of microorganisms yields a destruction rate greater than the additive rates of the independence agents. The synergistic mechanism shows a proportional dependency on radiation dose rate an Arrhenius dependency on temperature, and a dependency on relative humidity. Maximum synergism occurs under conditions where heat and radiation individually destroy microorganisms at approximately equal rates. Larger synergistic advantage is possible at low relative humidities rather than at high relative humidities.

Bacillus subtilis↗
PubMed1975

[Effects of drugs and environmental factors on ciliary movement (author's transl)].

The effects of a number of drugs, potassium and calcium ions, and air humidity on mucociliary function were studied in isolated preparations of rats bronchial tree. Adrenergic drugs increased the rate of ciliary beat significantly. Cilioexitation also occurred, though to a smaller degree, after application of acetylcholine, pilocarpine, aminophylline, prednisolone, KI and NH4C1. Serotonin, histamine, and acetylcystein did not change ciliary frequency to any significant degree; however, histamine in high concentrations caused ciliary incoordination. Codein and normetadon, nicotine and pentobarbital had a dose-dependent ciliodepressive effect. However, small concentrations of nicotine and pentobarbital were slightly stimulative. Methysergid and phentolamine were slightly ciliodepressive. Alterations of the concentrations of calcium and potassium ions in the nutritive solution influenced ciliary frequency but had no effect on other characteristic features of the ciliary movement. The ciliated epithelium of the bronchial tree could be irreversibly damaged by air having low relative humidity.

Acetylcholine↗
PubMed1977

Seasonal variation of cardiac failure in northern Nigeria.

The number of patients with cardiac failure admitted to hospital in Zaria, Nigeria, month by month during 1972-75 differed highly significantly between the cooler dry months and the hot wet months. The reasons are uncertain, but seasonal changes in blood-pressure and the effects of heat on the circulation and of humidity on the efficiency of sweating may be responsible.

Aortic Valve Insufficiency↗
PubMed2025

Eco-Evolutionary Genomics Reveal Mountain Range-Specific Adaptation and Intraspecific Variation in Vulnerability to Climate Change of Alpine Endemics.

Alpine plants restricted to rocky habitats exhibit intraspecific diversification due to range fragmentation during Holocene warming, complicating predictions of their climate vulnerability. A lack of understanding of eco-evolutionary mechanisms driving their response to climate change results in ineffective conservation efforts. To uncover the genomic basis of their diversification and explain spatial patterns of their vulnerability, we combine landscape genomics and species distribution modelling. Our model, the Campanula lehmanniana complex, occurs in three distinct central Asian mountain ranges, considered both a biodiversity hotspot and a vascular plant diversity darkspot. Genome-environment association confirmed the adaptive basis of intraspecific diversification, driven by numerous loci of small effect. Genomic and ecological data indicate mountain range-specific climate sensitivity driven by altitude, temperature and precipitation. The cold-dry adapted group from Zeravshan-Hissar Mts will face niche decline but show a higher degree of preadaptation to future climate, while the temperate-humid group from Tian Shan shows an opposite response, with a higher risk of maladaptation despite predicted niche expansion. Maladapted populations at northern margins may require an influx of adaptive variation to cope with predicted changes. However, limited landscape connectivity between island-like habitats, combined with long migration distances required to minimise genotype-environment disruption, highlights the role of human-assisted migration in enabling evolutionary rescue. These results underscore the need to facilitate gene flow from pre- to maladapted populations and the importance of population-specific approaches to inform effective conservation strategies in heterogeneous mountain ecosystems. The results may be relevant to numerous Central Asian mountain species that show similar phylogeographic patterns.

Climate Change↗
PubMed1979

The effect of controlled temperature variations on growth rate and blood pressure, hematocrit, and hemoglobin values in the turkey.

Hypertensive and hypotensive strains of turkeys were observed for the possibility of a synergistic response between hypertension and temperature stress. The birds in four experiments were placed in chambers with temperature settings of 15.6, 26.7, and 37.8 C (humidity approximately 60%) and an ambient control. The temperature effect was measured by comparing the responses in body weight-gain, systolic blood pressure, and hematocrit and hemoglobin values. In each experiment both hypertensive and hypotensive strains in the 37.8 C chamber had a significantly lower (P less than or equal to .05) weight gain than those in the other chambers. The 26.7 C chamber had the next lowest weight gain. Considerably more variability in weight gain was observed in the hypertensive strain. Systolic blood pressure data were similar for all experiments. The lowest average blood pressures were recorded in the 37.8 C chamber. The high and low blood pressure strains showed overall average decreases in blood pressure of 28% and 14%, respectively. There was no consistent response in hematocrit and hemoglobin values due to temperature stress. Overall average hematocrit values were 39.1 and 38.0% for the hypertensive and hypotensive strains, respectively, while average hemoglobin values were 11.8 and 12.2 g/dl. The hypertensive strain showed more variation in weight gain, a greater percentage drop in blood pressure, and a 19% mortality rate in the high temperature chambers. These factors indicate that hypertension is an added factor in the overall stress of these birds.

Animals↗
PubMed1977

Thermorespiratory responses of shorn and unshorn sheep to mild heat stress.

Three 3-year-old ewes with surgically exteriorized carotid loops were twice exposed to ambient temperatures (Ta) of 25, 30, 35 and 40 C (at constant 40% relative humidity) for 120 min in the presence (6.6 cm) and absence (less than 0.3 cm) of fleece. Thermoregulatory responses were evaluated during the last 30 min of each exposure by measurements of rectal (Tre), 6 skin surface temperatures (Ts), respiratory frequency (f), oxygen consumption (Vo2) and respiratory evaporative heat (Er); arterial blood samples were analyzed for pH, Pco2 and HCO-3 concentration. Both shorn and unshorn sheep exhibited a progressive increase in f, Er and Ts as Ta was elevated, with the unshorn group showing a higher Er than the shorn sheep at each Ta without a significant change in heat production. Er was found to be the principal avenue of heat loss, accounting for as much as 59% of the total in the shorn sheep compared to65% for the unshorn sheep. Increases in Er were accompanied by a decline in the arterial Pco2 which was linearly related to the Ta in both shorn and unshorn sheep. These data suggest that in defending against hyperthermia, sheep appear unable to increase Er without a concurrent elevation in Va at nearly allstages of acute heat stress.

Animals↗
PubMed1979

Herpesvirus hominis antibodies among children and young adults in Ibadan.

A total of 422 sera collected from children and young adults living in Ibadan, Nigeria, has been examined for the presence of antibodies to type 1 and type 2 herpesvirus hominis. Type 1 antibodies were rapidly acquired from the age of 1 year onwards, reflecting the relatively poor living standards and the overcrowded accommodation among the population studied. Type 2 antibodies were acquired between the ages of 3 and 5 years. It is suggested that non-venereal spread of the virus must be responsible; prolonged survival of the virus on fomites, owing to the high environmental humidity, possibly accounts for this.

Adolescent↗
PubMed2024

A trait-based ecological perspective on the soil microbial antibiotic-related genetic machinery.

Antibiotic resistance crisis dictates the need for resistance monitoring and the search for new antibiotics. The development of monitoring protocols is hindered by the great diversity of resistance factors, while the "streetlight effect" denies the possibility of discovering novel drugs based on existing databases. In this study, we address these challenges using high-throughput environmental screening viewed from a trait-based ecological perspective. Through an in-depth analysis of the metagenomes of 658 topsoil samples spanning Europe, we explored the distribution of 241 prokaryotic and fungal genes responsible for producing metabolites with antibiotic properties and 485 antibiotic resistance genes. We analyzed the diversity of these gene collections at different levels and modeled the distribution of each gene across environmental gradients. Our analyses revealed several nonparallel distribution patterns of the genes encoding sequential steps of enzymatic pathways synthesizing large antibiotic groups, pointing to gaps in existing databases and suggesting potential for discovering new analogues of known antibiotics. We show that agricultural activity caused a continental-scale homogenization of microbial antibiotic-related machinery, emphasizing the importance of maintaining indigenous ecosystems within the landscape mosaic. Based on the relationships between the proportion of the genes in the metagenomes with the main predictors (soil pH, land cover type, climate temperature and humidity), we illustrate how the properties of chemical structures dictate the distribution of the genes responsible for their synthesis across environments. With this understanding, we propose general principles to facilitate the discovery of antibiotics, including principally new ones, establish abundance baselines for antibiotic resistance genes, and predict their dissemination.

Soil Microbiology↗
PubMed1978

Adrenal responsiveness in pre- and postpartum dairy cows.

Adrenal responsiveness was evaluated by injecting 10 multiparous dairy cows with 200 IU adrenocorticotropin between -13 and -2 days prepartum (I) and postpartum between 24 and 40 h (II) and 21 and 24 days (III). Concentrations of glucocorticoids following injection were influenced by day of injection, temperature, and minimum percent relative humidity but not by breed, breed X injection day interaction, or age of cow. Likewise differences in regressions for adrenal response and mean response (ng/ml) for the three injections were nil. Mean concentrations at peak (45, 60, and 120 min postinjection samples) adjusted for preinjection concentrations also did not differ for the three periods of injection. Mean concentrations of glucocorticoids in plasma for daily samples between -13 and -2 days prepartum were 5.3 +/- .4 (n = 61), reached a peak of 14.8 +/- .3 ng/ml the day of calving, and remained high for 2 days postpartum. Estradiol increased through prepartum sampling from 23.3 to 339.6 +/- 94.1 pg/ml the day of calving, then declined abruptly. Progestins began to decline about -5 days prepartum from mean concentration of 4.09 +/- .62 (n = 25) and attained low concentrations (.30 +/- .06 ng/ml) 2 days postpartum. Although there was a surge of glucocorticoids at parturition, this was not associated with a modification in adrenal responsiveness or with prepartum concentrations of other steroid hormones of plasma. Adrenal potential in prepartum and postpartum dairy cows appears well maintained.

Adrenal Glands↗
PubMed1978

Monitoring ventilation during anesthesia.

In patients under anesthesia, ventilation is often monitored less adequately than circulation. A simple method, neglected in adults, is the use of a precordial or oesophageal stethoscope. Respiratory volumes may be measured directly, or inferred from flowrates or pressure changes. A rough measurement of inspired volumes may be made using a nonrebreathing valve, and controlling fresh gas input to maintain a constant underfilled reservoir bag. Spirometry of expired volumes is difficult and requires sophisticated apparatus. Respiratory volumes are easily inferred from flowrates using the Wright or Dräger respirometers. Flowrates may also be inferred from pressure changes, which are easy to record, as in the pneumotachorgraph. Accurate measurements require attention to many details, such as linearity of the transducer response over the flowrates measured. Calibration should be with the anesthetic gases used, at controlled temperature and humidity. Positive pressure ventilation peaks give a high flow artefact, and electronic drift requires regular recalibration. Electrical impedance changes may also be used to infer and record respiratory volumes, with reasonable accuracy if individual calibration is carried out. Anesthesia offers excellent opportunities to measure compliance and resistance, but itself changes these values, so that relation to normal values or changes due to pathology is difficult. Occlusion pressure is also readily measured during anesthesia, as an indication of respiratory drive, but rigid control of all other factors affecting respiratory muscle tensions is necessary.

Airway Resistance↗
PubMedDate not supplied

Clinical assessment of laboratory rodents on long term bioassay studies.

The disease status of laboratory rodents should be clinically assessed before the animals are placed on toxicological bioassay programs. This is especially important when the stress of dietary or parenteral intake of toxic substances may trigger the clinical onset of latent diseases in research animals. In clinical evaluation of rodents, the environmental influence on biochemical, physiological and behavioral status of the animals must be continually monitored. Temperature, humidity, ventilation, lighting, and the microenvironment of the cage will all influence, independently or in consort, the response of the animal to various microbial or chemical insults. Unwanted variables in the diet can also markedly after the biological response of the animal and thus alter interpretation of experimental data. Adequately trained personnel, both professional and technical, must be available to provide daily care, clinical observation, and necessary treatment if signs of illness are noted in the laboratory rodent or bioassay experimentation. Clinical signs associated with commonly encountered diseases in laboratory rodents are briefly described. Clinical surveillance and assessment of rodents in part consists of recognition of and detailed recording of clinical signs, coupled with proper diagnostic resources to substantiate clinical observations. It is possible, with proper diagnosis, to evaluate the overall effect of a particular disease on the animal's health, the likelihood that the disease is jeopardizing the health of the other animals on test, and the effect of the disorder on interpretation of experimental results.

Animal Husbandry↗
PubMed2026

Whole-genome sequencing reveals divergent and shared selection signatures of heat stress adaptation in indigenous Ethiopian zebu cattle from dry-hot and humid-hot environments.

African zebu cattle (Bos indicus) exhibit remarkable adaptations to extreme thermal conditions, yet the genomic basis of this resilience remains incompletely characterized. Ethiopia provides a unique natural setting in which closely related zebu populations have adapted divergently to dry-hot (DHETZ) and humid-hot (HHETZ) climates. In this study, we reanalyzed publicly available whole-genome sequencing datasets from 46 Ethiopian zebu cattle from five populations and compared them with Asian zebu, Sudanese zebu, African taurine, and European taurine breeds. By integrating genome-wide SNP analysis, population genetic structure assessment, and multiple selection scans (iHS, Hp, XP-EHH, and XP-CLR), we identified distinct and shared selection signatures between DHETZ and HHETZ. We detected 33.7 million and 34.2 million biallelic autosomal SNPs in DHETZ and HHETZ, respectively. Ethiopian zebu clustered closely with Sudanese zebu but showed clear divergence from Asian zebu and taurine breeds. DHETZ and HHETZ exhibited very low genetic differentiation (FST = 0.0063), consistent with their shared ancestry; however, each group displayed unique selection signals. In DHETZ, iHS and Hp detected 298 and 113 candidate regions, respectively, whereas in HHETZ, they detected 244 and 138 regions, respectively. Cross-population XP-EHH and XP-CLR analyses identified 163 and 227 divergent regions between DHETZ and HHETZ, respectively. Integration of the four selection scans identified 19 high-confidence candidate regions in DHETZ and 13 in HHETZ. DHETZ showed strong selection in genes involved in oxidative stress regulation, protein folding, mitochondrial function, and vascular remodeling, including SESN2, DNAJC8, GRPEL2, ABLIM3, and AFAP1L1. In contrast, HHETZ displayed signatures in genes associated with immune responses, energy metabolism, and angiogenesis inhibition, including MYD88, PRKACA, PRKACB, and WIF1. Several genes, including VEGFC, TNIP3, and DMXL2, were under selection in both groups, suggesting conserved mechanisms of thermotolerance and reproductive adaptation. The shared VEGFC signal and the HHETZ-specific WIF1 signal may indicate a distinct vascular regulatory mechanism in the dry-hot and humid-hot environments. Our results reveal a dual pattern of genomic adaptation in Ethiopian zebu cattle and provide candidate loci for future validation and climate-resilient livestock breeding.

Animals↗
PubMed1976

Evaluation of Moloney murine sarcoma and leukemia virus complex as a model for airborne oncogenic virus biohazards: survival of airborne virus and exposure of mice.

Aerosols of the Moloney murine sarcoma virus (MuSV-M) and leukemia virus (MuLV-M) complex (MuSV-M/MuLV-M) were generated from refluxing atomizers and then aged in rotating drums at 21 degrees C holding temperature with relative humidities ranging from 25 to 76%. The MuSV-M and MuLV-M aerosolized from the same tumor extract preparation survived almost equally at the four humidity levels. Both viruses remained viable in the airborne state for at least 2 hours after aerosolization. When mice were exposed to airborne MuSV-M/MuLV-M, no macroscopic lesions were observed in lungs or other tissues examined during the 2-month postexposure period. On the basis of this study, MuSV-M was determined unsuitable as a "model system" in which a simple aerosol dose response could be used for biohazard evaluation of oncogenic virus aerosols.

Aerosols↗