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1.
Horm Metab Res ; 53(9): 575-587, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34496408

RESUMEN

Global warming and the rising prevalence of obesity are well described challenges of current mankind. Most recently, the COVID-19 pandemic arose as a new challenge. We here attempt to delineate their relationship with each other from our perspective. Global greenhouse gas emissions from the burning of fossil fuels have exponentially increased since 1950. The main contributors to such greenhouse gas emissions are manufacturing and construction, transport, residential, commercial, agriculture, and land use change and forestry, combined with an increasing global population growth from 1 billion in 1800 to 7.8 billion in 2020 along with rising obesity rates since the 1980s. The current Covid-19 pandemic has caused some decline in greenhouse gas emissions by limiting mobility globally via repetitive lockdowns. Following multiple lockdowns, there was further increase in obesity in wealthier populations, malnutrition from hunger in poor populations and death from severe infection with Covid-19 and its virus variants. There is a bidirectional relationship between adiposity and global warming. With rising atmospheric air temperatures, people typically will have less adaptive thermogenesis and become less physically active, while they are producing a higher carbon footprint. To reduce obesity rates, one should be willing to learn more about the environmental impact, how to minimize consumption of energy generating carbon dioxide and other greenhouse gas emissions, and to reduce food waste. Diets lower in meat such as a Mediterranean diet, have been estimated to reduce greenhouse gas emissions by 72%, land use by 58%, and energy consumption by 52%.


Asunto(s)
Cambio Climático , Obesidad/etiología , Agricultura/economía , Agricultura/tendencias , COVID-19/complicaciones , COVID-19/epidemiología , COVID-19/patología , Cambio Climático/historia , Comorbilidad , Disruptores Endocrinos/toxicidad , Ambiente , Exposición a Riesgos Ambientales/historia , Exposición a Riesgos Ambientales/estadística & datos numéricos , Gases de Efecto Invernadero/toxicidad , Historia del Siglo XIX , Historia del Siglo XX , Historia del Siglo XXI , Humanos , Obesidad/epidemiología , Obesidad/metabolismo , Pandemias , Factores de Riesgo
2.
Zool Res ; 42(5): 592-605, 2021 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-34387415

RESUMEN

The large yellow croaker (Larimichthys crocea), which is an economically important mariculture fish in China, is often exposed to environmental hypoxia. Reactive oxygen species (ROS) homeostasis is essential for the maintenance of normal physiological conditions in an organism. Direct evidence that environmental hypoxia leads to ROS overproduction is scarce in marine fish. Furthermore, the sources of ROS overproduction in marine fish under hypoxic stress are poorly known. In this study, we investigated the effects of hypoxia on redox homeostasis in L. crocea and the impact of impaired redox homeostasis on fish. We first confirmed that hypoxia drove ROS production mainly via the mitochondrial electron transport chain and NADPH oxidase complex pathways in L. crocea and its cell line (large yellow croaker fry (LYCF) cells). We subsequently detected a marked increase in the antioxidant systems of the fish. However, imbalance between the pro-oxidation and antioxidation systems ultimately led to excessive ROS and oxidative stress. Cell viability showed a remarkable decrease while oxidative indicators, such as malondialdehyde, protein carbonylation, and 8-hydroxy-2 deoxyguanosine, showed a significant increase after hypoxia, accompanied by tissue damage. N-acetylcysteine (NAC) reduced ROS levels, alleviated oxidative damage, and improved cell viability in vitro. Appropriate uptake of ROS scavengers (e.g., NAC and elamipretide Szeto-Schiller-31) and inhibitors (e.g., apocynin, diphenylene iodonium, and 5-hydroxydecanoate) may be effective at overcoming hypoxic toxicity. Our findings highlight previously unstudied strategies of hypoxic toxicity resistance in marine fish.


Asunto(s)
Antioxidantes/metabolismo , Peces/metabolismo , Estrés Oxidativo/fisiología , Oxígeno/química , Oxígeno/metabolismo , Especies Reactivas de Oxígeno , Animales , Línea Celular , Supervivencia Celular , Ambiente , Homeostasis , NADP
3.
Vet Dermatol ; 2021 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-34415086

RESUMEN

The ecology of the early environment - including microbial diversity, nutrition, nature, social interactions and the totality of exposures in the wider "exposome" - have life-long implications for all aspects of health and resilience. In particular, the emergence of "microbiome science" provides new evidence for vital relationships between biodiversity and health at every level. New perspectives of ecological interdependence connect personal and planetary health; the human health crisis cannot be separated from the social, political and economic "ecosystems" otherwise driving dysbiosis (from its etymological root, "life in distress") at every level. Adverse changes in macroscale ecology - of food systems, lifestyle behaviours, socioeconomic disadvantage and environmental degradation - all impact the microbial systems sitting at the foundations of all ecosystems. In particular, changes in the function and composition of the human-associated microbiome have been implicated in the mounting global burden of noncommunicable diseases (NCDs), exacerbating inflammation and metabolic dysregulation through multiple pathways across the lifespan. This "dysbiotic drift" (adverse shifts in ecology at all scales) underscores the need for ecological approaches aimed at restoring symbiosis, balance and mutualism. While there is promise with supplement-based strategies (e.g. probiotics, prebiotics), it is essential to focus on upstream factors implicated in dysbiosis, including the health of wider environments, lifestyle, nature relatedness, and the social policies and practices which can facilitate or inhibit dysbiotic drift. This also calls for ambitious integrative approaches which not only define these interconnections, but also capitalize on them to create novel, collaborative and mutualistic solutions to our vast interdependent global challenges.

4.
Commun Biol ; 4(1): 848, 2021 07 07.
Artículo en Inglés | MEDLINE | ID: mdl-34234264

RESUMEN

Multi-scale macroalgae growth models are required for the efficient design of sustainable, economically viable, and environmentally safe farms. Here, we develop a multi-scale model for Ulva sp. macroalgae growth and nitrogen sequestration in an intensive cultivation farm, regulated by temperature, light, and nutrients. The model incorporates a range of scales by incorporating spatial effects in two steps: light extinction at the reactor scale (1 m) and nutrient absorption at the farm scale (1 km). The model was validated on real data from an experimental reactor installed in the sea. Biomass production rates, chemical compositions, and nitrogen removal were simulated under different seasons, levels of dilution in the environment and water-exchange rate in the reactor. This multi-scale model provides an important tool for environmental authorities and seaweed farmers who desire to upscale to large bioremediation and/or macroalgae biomass production farms, thus promoting the marine sustainable development and the macroalgae-based bioeconomy.


Asunto(s)
Algoritmos , Modelos Biológicos , Nitrógeno/metabolismo , Algas Marinas/metabolismo , Ulva/metabolismo , Biomasa , Conservación de los Recursos Naturales/métodos , Ecosistema , Reproducibilidad de los Resultados , Estaciones del Año , Algas Marinas/crecimiento & desarrollo , Ulva/crecimiento & desarrollo
5.
Commun Biol ; 4(1): 869, 2021 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-34267317

RESUMEN

The tropical forests of Central America serve a pivotal role as biodiversity hotspots and provide ecosystem services securing human livelihood. However, climate change is expected to affect the species composition of forest ecosystems, lead to forest type transitions and trigger irrecoverable losses of habitat and biodiversity. Here, we investigate potential impacts of climate change on the environmental suitability of main plant functional types (PFTs) across Central America. Using a large database of occurrence records and physiological data, we classify tree species into trait-based groups and project their suitability under three representative concentration pathways (RCPs 2.6, 4.5 and 8.5) with an ensemble of state-of-the-art correlative modelling methods. Our results forecast transitions from wet towards generalist or dry forest PFTs for large parts of the study region. Moreover, suitable area for wet-adapted PFTs is projected to latitudinally diverge and lose connectivity, while expected upslope shifts of montane species point to high risks of mountaintop extinction. These findings underline the urgent need to safeguard the connectivity of habitats through biological corridors and extend protected areas in the identified transition hotspots.


Asunto(s)
Cambio Climático , Ecosistema , Agricultura Forestal/estadística & datos numéricos , Plantas/metabolismo , Árboles/metabolismo , Animales , Biodiversidad , América Central , Conservación de los Recursos Naturales/métodos , Conservación de los Recursos Naturales/estadística & datos numéricos , Conservación de los Recursos Naturales/tendencias , Agricultura Forestal/métodos , Agricultura Forestal/tendencias , Geografía , Humanos , Modelos Teóricos , Plantas/clasificación , Dinámica Poblacional , Árboles/clasificación , Clima Tropical
6.
Int J Mol Sci ; 22(12)2021 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-34204586

RESUMEN

Thyroid hormones are necessary for the normal functioning of physiological systems. Therefore, knowledge of any factor (whether genetic, environmental or intrinsic) that alters the levels of thyroid-stimulating hormone (TSH) and thyroid hormones is crucial. Genetic factors contribute up to 65% of interindividual variations in TSH and thyroid hormone levels, but many environmental factors can also affect thyroid function. This review discusses studies that have analyzed the impact of environmental factors on TSH and thyroid hormone levels in healthy adults. We included lifestyle factors (smoking, alcohol consumption, diet and exercise) and pollutants (chemicals and heavy metals). Many inconsistencies in the results have been observed between studies, making it difficult to draw a general conclusion about how a particular environmental factor influences TSH and thyroid hormone levels. However, lifestyle factors that showed the clearest association with TSH and thyroid hormones were smoking, body mass index (BMI) and iodine (micronutrient taken from the diet). Smoking mainly led to a decrease in TSH levels and an increase in triiodothyronine (T3) and thyroxine (T4) levels, while BMI levels were positively correlated with TSH and free T3 levels. Excess iodine led to an increase in TSH levels and a decrease in thyroid hormone levels. Among the pollutants analyzed, most studies observed a decrease in thyroid hormone levels after exposure to perchlorate. Future studies should continue to analyze the impact of environmental factors on thyroid function as they could contribute to understanding the complex background of gene-environment interactions underlying the pathology of thyroid diseases.


Asunto(s)
Ambiente , Regulación de la Expresión Génica , Interacción Gen-Ambiente , Hormonas Tiroideas/genética , Tirotropina/genética , Animales , Biomarcadores , Dieta , Contaminantes Ambientales , Antecedentes Genéticos , Humanos , Estilo de Vida , Hormonas Tiroideas/metabolismo , Tirotropina/metabolismo
7.
Nat Commun ; 12(1): 4398, 2021 07 20.
Artículo en Inglés | MEDLINE | ID: mdl-34285226

RESUMEN

Studies in rodents and captive primates suggest that the early-life social environment affects future phenotype, potentially through alterations to DNA methylation. Little is known of these associations in wild animals. In a wild population of spotted hyenas, we test the hypothesis that maternal care during the first year of life and social connectedness during two periods of early development leads to differences in DNA methylation and fecal glucocorticoid metabolites (fGCMs) later in life. Here we report that although maternal care and social connectedness during the den-dependent life stage are not associated with fGCMs, greater social connectedness during the subadult den-independent life stage is associated with lower adult fGCMs. Additionally, more maternal care and social connectedness after den independence correspond with higher global (%CCGG) DNA methylation. We also note differential DNA methylation near 5 genes involved in inflammation, immune response, and aging that may link maternal care with stress phenotype.


Asunto(s)
Epigénesis Genética/fisiología , Hyaenidae/psicología , Conducta Materna/fisiología , Medio Social , Estrés Psicológico/diagnóstico , Envejecimiento/genética , Envejecimiento/psicología , Animales , Metilación de ADN/fisiología , Heces/química , Femenino , Glucocorticoides/análisis , Glucocorticoides/metabolismo , Hyaenidae/genética , Hyaenidae/crecimiento & desarrollo , Masculino , Estrés Psicológico/genética , Estrés Psicológico/metabolismo , Estrés Psicológico/psicología
8.
Int J Mol Sci ; 22(12)2021 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-34208294

RESUMEN

Cryptococcus neoformans is a facultative intracellular pathogen responsible for fungal meningoencephalitis primarily in immunocompromised individuals. It has become evident the pathogenicity of C. neoformans is dependent on the fungal cell's environment. The differential expression of virulence factors, based on the cell's environmental conditions, is one mechanism allowing for the environmental control of the pathogenic ability of C. neoformans. Here, we discuss how these virulence factors (including melanin, the polysaccharide capsule, and Antiphagocytic protein 1) have been shown to be differentially expressed dependent on the cell's environment. The genetics and signaling pathways leading to the environmental-dependent regulation of virulence factors will also be examined. Susceptibility to antifungal therapeutics is also regulated by the environment, and thus affects the pathogenic abilities of C. neoformans and disease outcomes. This review will also examine the role of the C. neoformans's environment on antifungal susceptibilities, and the genetics and signaling pathways responsible for these susceptibility alterations. By examining the complex interplay between the environment and the pathogenicity of C. neoformans, we have a better understanding of the intricacies of the pathogen-environment interaction and how to exploit this interaction to develop the most effective treatment protocols.


Asunto(s)
Antifúngicos/farmacología , Cryptococcus neoformans/efectos de los fármacos , Cryptococcus neoformans/patogenicidad , Ambiente , Factores de Virulencia/metabolismo , Animales , Humanos , Pulmón/microbiología , Pruebas de Sensibilidad Microbiana
9.
Int J Mol Sci ; 22(14)2021 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-34299332

RESUMEN

Exposure of rodents to <20 cGy Space Radiation (SR) impairs performance in several hippocampus-dependent cognitive tasks, including spatial memory. However, there is considerable inter-individual susceptibility to develop SR-induced spatial memory impairment. In this study, a robust label-free mass spectrometry (MS)-based unbiased proteomic profiling approach was used to characterize the composition of the hippocampal proteome in adult male Wistar rats exposed to 15 cGy of 1 GeV/n 48Ti and their sham counterparts. Unique protein signatures were identified in the hippocampal proteome of: (1) sham rats, (2) Ti-exposed rats, (3) Ti-exposed rats that had sham-like spatial memory performance, and (4) Ti-exposed rats that impaired spatial memory performance. Approximately 14% (159) of the proteins detected in hippocampal proteome of sham rats were not detected in the Ti-exposed rats. We explored the possibility that the loss of the Sham-only proteins may arise as a result of SR-induced changes in protein homeostasis. SR-exposure was associated with a switch towards increased pro-ubiquitination proteins from that seen in Sham. These data suggest that the role of the ubiquitin-proteome system as a determinant of SR-induced neurocognitive deficits needs to be more thoroughly investigated.


Asunto(s)
Radiación Cósmica , Hipocampo/efectos de la radiación , Proteoma/metabolismo , Ubiquitina/metabolismo , Animales , Cognición/efectos de la radiación , Relación Dosis-Respuesta en la Radiación , Medio Ambiente Extraterrestre , Hipocampo/metabolismo , Masculino , Proteómica/métodos , Ratas , Ratas Wistar , Memoria Espacial/efectos de la radiación
10.
Nat Genet ; 53(7): 955-961, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34140685

RESUMEN

The interplay between light receptors and PHYTOCHROME-INTERACTING FACTORs (PIFs) serves as a regulatory hub that perceives and integrates environmental cues into transcriptional networks of plants1,2. Although occupancy of the histone variant H2A.Z and acetylation of histone H3 have emerged as regulators of environmentally responsive gene networks, how these epigenomic features interface with PIF activity is poorly understood3-7. By taking advantage of rapid and reversible light-mediated manipulation of PIF7 subnuclear localization and phosphorylation, we simultaneously assayed the DNA-binding properties of PIF7, as well as its impact on chromatin dynamics genome wide. We found that PIFs act rapidly to reshape the H2A.Z and H3K9ac epigenetic landscape in response to a change in light quality. Furthermore, we discovered that PIFs achieve H2A.Z removal through direct interaction with EIN6 ENHANCER (EEN), the Arabidopsis thaliana homolog of the chromatin remodeling complex subunit INO80 Subunit 6 (Ies6). Thus, we describe a PIF-INO80 regulatory module that is an intermediate step for allowing plants to change their growth trajectory in response to environmental changes.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Cromatina/genética , Cromatina/metabolismo , Ambiente , Regulación de la Expresión Génica de las Plantas , Interacción Gen-Ambiente , Epigénesis Genética , Variación Genética , Histonas/genética , Histonas/metabolismo , Procesamiento Proteico-Postraduccional
11.
Viruses ; 13(5)2021 05 12.
Artículo en Inglés | MEDLINE | ID: mdl-34066231

RESUMEN

The spread of SARS-CoV-2 and the resulting disease COVID-19 has killed over 2.6 million people as of 18 March 2021. We have used a modified susceptible, infected, recovered (SIR) epidemiological model to predict how the spread of the virus in regions of France will vary depending on the proportions of variants and on the public health strategies adopted, including anti-COVID-19 vaccination. The proportion of SARS-CoV-2 variant B.1.1.7, which was not detected in early January, increased to become 60% of the forms of SARS-CoV-2 circulating in the Toulouse urban area at the beginning of February 2021, but there was no increase in positive nucleic acid tests. Our prediction model indicates that maintaining public health measures and accelerating vaccination are efficient strategies for the sustained control of SARS-CoV-2.


Asunto(s)
COVID-19/transmisión , SARS-CoV-2/genética , COVID-19/epidemiología , COVID-19/genética , Vacunas contra la COVID-19/genética , Métodos Epidemiológicos , Francia/epidemiología , Humanos , Salud Pública , SARS-CoV-2/metabolismo , Vacunación/estadística & datos numéricos , Vacunación/tendencias
12.
Nat Commun ; 12(1): 3892, 2021 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-34162876

RESUMEN

The decline of brain function during aging is associated with epigenetic changes, including DNA methylation. Lifestyle interventions can improve brain function during aging, but their influence on age-related epigenetic changes is unknown. Using genome-wide DNA methylation sequencing, we here show that experiencing a stimulus-rich environment counteracts age-related DNA methylation changes in the hippocampal dentate gyrus of mice. Specifically, environmental enrichment prevented the aging-induced CpG hypomethylation at target sites of the methyl-CpG-binding protein Mecp2, which is critical to neuronal function. The genes at which environmental enrichment counteracted aging effects have described roles in neuronal plasticity, neuronal cell communication and adult hippocampal neurogenesis and are dysregulated with age-related cognitive decline in the human brain. Our results highlight the stimulating effects of environmental enrichment on hippocampal plasticity at the level of DNA methylation and give molecular insights into the specific aspects of brain aging that can be counteracted by lifestyle interventions.


Asunto(s)
Envejecimiento , Islas de CpG/genética , Metilación de ADN , Ambiente , Hipocampo/metabolismo , Factores de Edad , Animales , Giro Dentado/metabolismo , Epigenómica/métodos , Femenino , Hipocampo/citología , Humanos , Ratones Endogámicos C57BL , Neurogénesis/genética , Plasticidad Neuronal/genética , Neuronas/metabolismo
13.
Nat Commun ; 12(1): 3875, 2021 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-34162891

RESUMEN

The conservation of ecosystems and their biodiversity has numerous co-benefits, both for local societies and for humankind worldwide. While the co-benefit of climate change mitigation through so called blue carbon storage in coastal ecosystems has raised increasing interest in mangroves, the relevance of multifaceted biodiversity as a driver of carbon storage remains unclear. Sediment salinity, taxonomic diversity, functional diversity and functional distinctiveness together explain 69%, 69%, 27% and 61% of the variation in above- and belowground plant biomass carbon, sediment organic carbon and total ecosystem carbon storage, respectively, in the Sundarbans Reserved Forest. Functional distinctiveness had the strongest explanatory power for carbon storage, indicating that blue carbon in mangroves is driven by the functional composition of diverse tree assemblages. Protecting and restoring mangrove biodiversity with site-specific dominant species and other species of contrasting functional traits would have the co-benefit of maximizing their capacity for climate change mitigation through increased carbon storage.


Asunto(s)
Avicennia/metabolismo , Biodiversidad , Secuestro de Carbono , Carbono/metabolismo , Conservación de los Recursos Naturales/métodos , Algoritmos , Avicennia/crecimiento & desarrollo , Biomasa , Ecosistema , Sedimentos Geológicos , Modelos Teóricos
14.
Nature ; 594(7863): 345-355, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34135518

RESUMEN

Artificial intelligence (AI) is accelerating the development of unconventional computing paradigms inspired by the abilities and energy efficiency of the brain. The human brain excels especially in computationally intensive cognitive tasks, such as pattern recognition and classification. A long-term goal is de-centralized neuromorphic computing, relying on a network of distributed cores to mimic the massive parallelism of the brain, thus rigorously following a nature-inspired approach for information processing. Through the gradual transformation of interconnected computing blocks into continuous computing tissue, the development of advanced forms of matter exhibiting basic features of intelligence can be envisioned, able to learn and process information in a delocalized manner. Such intelligent matter would interact with the environment by receiving and responding to external stimuli, while internally adapting its structure to enable the distribution and storage (as memory) of information. We review progress towards implementations of intelligent matter using molecular systems, soft materials or solid-state materials, with respect to applications in soft robotics, the development of adaptive artificial skins and distributed neuromorphic computing.


Asunto(s)
Inteligencia Artificial , Materiales Biomiméticos , Biomimética/tendencias , Diseño de Equipo , Robótica/tendencias , Coloides , Ambiente , Enzimas/metabolismo , Homeostasis , Humanos , Estimulación Física , Piel Artificial
15.
Nat Nanotechnol ; 16(6): 617-629, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34117462

RESUMEN

The adsorption of biomolecules to the surface of engineered nanomaterials, known as corona formation, defines their biological identity by altering their surface properties and transforming the physical, chemical and biological characteristics of the particles. In the first decade since the term protein corona was coined, studies have focused primarily on biomedical applications and human toxicity. The relevance of the environmental dimensions of the protein corona is still emerging. Often referred to as the eco-corona, a biomolecular coating forms upon nanomaterials as they enter the environment and may include proteins, as well as a diverse array of other biomolecules such as metabolites from cellular activity and/or natural organic matter. Proteins remain central in studies of eco-coronas because of the ease of monitoring and structurally characterizing proteins, as well as their crucial role in receptor engagement and signalling. The proteins within the eco-corona are optimal targets to establish the biophysicochemical principles of corona formation and transformation, as well as downstream impacts on nanomaterial uptake, distribution and impacts on the environment. Moreover, proteins appear to impart a biological identity, leading to cellular or organismal recognition of nanomaterials, a unique characteristic compared with natural organic matter. We contrast insights into protein corona formation from clinical samples with those in environmentally relevant systems. Principles specific to the environment are also explored to gain insights into the dynamics of interaction with or replacement by other biomolecules, including changes during trophic transfer and ecotoxicity. With many challenges remaining, we also highlight key opportunities for method development and impactful systems on which to focus the next phase of eco-corona studies. By interrogating these environmental dimensions of the protein corona, we offer a perspective on how mechanistic insights into protein coronas in the environment can lead to more sustainable, environmentally safe nanomaterials, as well as enhancing the efficacy of nanomaterials used in remediation and in the agri-food sector.


Asunto(s)
Ambiente , Nanoestructuras , Corona de Proteínas , Animales , Biodiversidad , Sustancias Húmicas , Nanoestructuras/química , Corona de Proteínas/química , Corona de Proteínas/metabolismo , Proyectos de Investigación
16.
Ecotoxicol Environ Saf ; 220: 112399, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-34091187

RESUMEN

The Rotimer, a rotifer-specific biopolymer, is an exogenic bioactive exudate secreted by different monogonant species (e.g. Euchlanis dilatata or Lecane bulla). The production of this viscoelastic biomolecule is induced by different micro-particles, thereby forming a special Rotimer-Inductor Conglomerate (RIC) in a web format. In this case, the water insoluble Carmine crystals, filtered to size (max. diameter was 50 µm), functioned as an inductor. The RIC production is an adequate empirical indicator to follow up this filamentous biopolymer secretion experientially; moreover, this procedure is very sensitive to the environmental factors (temperature, pH, metals and possible natural pollutant agents). The above mentioned species show completely different reactions to these factors, except to the presence of calcium and to the modulating effects of different drugs. One of the novelties of this work is that the Rotimer secretion and consequently, the RIC-formation is a mutually obligatory and evolutionary calcium-dependent process in the concerned monogonants. This in vivo procedure needs calcium, both for the physiology of animals and for fiber formation, particularly in the latter case. The conglomerate covered area (%) and the detection of the longest filament (mm) of the given RIC were the generally and simultaneously applied methods in the current modulating experiments. Exploring the regulatory (e.g. calcium-dependency) and stimulating (e.g. Lucidril effect) possibilities of biopolymer secretion are the basis for optimizing the RIC-production capacities of these micro-metazoans.


Asunto(s)
Biopolímeros/biosíntesis , Calcio/farmacología , Ambiente , Contaminantes Ambientales/farmacología , Exudados y Transudados , Rotíferos/metabolismo , Animales , Concentración de Iones de Hidrógeno , Rotíferos/efectos de los fármacos , Temperatura
17.
Int J Food Microbiol ; 351: 109268, 2021 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-34098467

RESUMEN

The increase in multidrug-resistant Salmonella enterica and its spread from food to humans are considered a serious public health concern worldwide. Little is currently known about the prevalence of extended-spectrum ß-lactamase (ESBL)-producing S. enterica in fish in Africa. Therefore, this study aimed to investigate the existence of ESBL-producing S. enterica in retail fish in Egypt. In total, 200 fish samples were collected randomly from various retail fish markets in Egypt. S. enterica were detected in 19 (9.5%; 95% CI: 5.8-14.4) of the fish samples analyzed. Of the 19 non-repetitive S. enterica isolates, 18 were serologically categorized into eight S. enterica serovars and a non-typable serovar. All 19 S. enterica isolates (100%) showed multidrug-resistant phenotypes to at least three classes of antimicrobials, and 11 (57.9%) exhibited an ESBL-resistant phenotype and harbored at least one ESBL-encoding gene. The ESBL-producing S. enterica serovars were as follows: Kentucky (3 isolates; 15.8%), Enteritidis (2 isolates; 10.5%), Typhimurium (2 isolates; 10.5%), and 1 isolate (5.3%) each of Infantis, Virchow, Paratyphi B, and Senftenberg. The identified ß-lactamase-encoding genes included ESBL-encoding genes blaCTX-M-3, blaCTX-M-14, blaCTX-M-15, blaSHV-1, blaSHV-2 and blaSHV-12; the AmpC ß-lactamase-encoding gene blaCMY-2; and the narrow-spectrum ß-lactamase-encoding genes blaTEM-1 and blaOXA-1. All S. enterica isolates were negative for carbapenemase-encoding genes. Molecular analysis of plasmid transferability and replicon typing revealed that most plasmids (with ß-lactamase-encoding genes) were transferrable, and the most common incompatibility groups were IncI1, IncA/C, IncHI1, and IncN. To the best of our knowledge, this is the first report for molecular characterization of ESBL-producing S. enterica in fish in Egypt. The occurrence of ESBL-producing S. enterica in retail fish constitutes a potential public health threat with the possibility of transmission of these strains with resistance genes to humans. Such transmission would exacerbate the resistance to an important class of antibiotics commonly used in hospitals to treat typhoid and non-typhoidal Salmonella infections.


Asunto(s)
Peces/microbiología , Salmonelosis Animal/microbiología , Salmonella enterica/metabolismo , beta-Lactamasas/metabolismo , Animales , Antibacterianos/farmacología , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Farmacorresistencia Bacteriana Múltiple/genética , Egipto/epidemiología , Humanos , Plásmidos/genética , Prevalencia , Salud Pública , Salmonelosis Animal/epidemiología , Salmonella enterica/efectos de los fármacos , Salmonella enterica/genética , Salmonella enterica/aislamiento & purificación , beta-Lactamasas/genética
18.
BMC Vet Res ; 17(1): 209, 2021 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-34098948

RESUMEN

BACKGROUND: Extreme panting under heat stress threatens dairy cattle milk production. Previous research has revealed that the gas exchange-mediated respiratory drive in critically ill dairy cattle with low O2 saturation induces panting. Vascular endothelial growth factor (VEGF) signaling may play important roles in immunosuppression and oxidative stress during severe respiratory stress responses in heat-stressed cattle. The objectives of this study were to transcriptomically analyze mRNA expression mediating heat-induced respiratory stress-associated panting, evaluate gas exchange, screen hub genes, and verify the expression of proteins encoded by differentially expressed genes in lymphocyte pathways. RESULTS: Jersey cattle were naturally heat-exposed. Physiological data were collected for response evaluation, and blood was collected for gas exchange and gene expression assays at 06:00, 10:00 and 14:00 continuously for 1 week. Lymphocytes were isolated from whole-blood samples for mRNA-seq and expression analysis of key pathway genes/proteins. The cattle respiration rates differed with time, averaging 51 bpm at 06:00, 76 bpm at 10:00, and 121 bpm at 14:00 (p < 0.05). Gas exchange analysis showed that both pH and pCO2 differed with time: they were 7.41 and 41 mmHg at 06:00, 7.45 and 37.5 mmHg at 10:00, and 7.49 and 33 mmHg at 14:00, respectively (p < 0.01). Sixteen heat-related differentially expressed genes (DEGs; 13 upregulated and 3 downregulated) were screened between 212 DEGs and 1370 heat stress-affected genes. Kyoto Encyclopedia of Genes and Genomes (KEGG) hub gene functional analysis annotated eleven genes to signal transduction, six genes to the immune response, and five genes to the endocrine response, including both prostaglandin-endoperoxide synthase 2 (PTGS2) and VEGF. Gene Ontology (GO) functional enrichment analysis revealed that oxygen regulation was associated with the phosphorus metabolic process, response to oxygen levels, response to decreased oxygen levels, response to hypoxia and cytokine activity terms. The main signaling pathways were the VEGF, hypoxia inducible factor-1(HIF-1), cytokine-cytokine receptor interaction and TNF pathways. Four genes involved Integrin beta 3 (ITBG3), PTGS2, VEGF, and myosin light chain 9 (MYL9) among the 16 genes related to immunosuppression, oxidative stress, and endocrine dysfunction were identified as participants in the VEGF signaling pathway and oxygenation. CONCLUSION: These findings help elucidate the underlying immune and oxygen regulation mechanisms associated with the VEGF signaling pathway in heat-stressed dairy cattle.


Asunto(s)
Enfermedades de los Bovinos/metabolismo , Trastornos de Estrés por Calor/veterinaria , Linfocitos/metabolismo , Transducción de Señal , Factor A de Crecimiento Endotelial Vascular/metabolismo , Animales , Bovinos , Enfermedades de los Bovinos/etiología , Enfermedades de los Bovinos/inmunología , Ambiente , Regulación de la Expresión Génica , Trastornos de Estrés por Calor/inmunología , Trastornos de Estrés por Calor/metabolismo , Respuesta al Choque Térmico , Hipoxia/inmunología , Hipoxia/metabolismo , Hipoxia/veterinaria , Tolerancia Inmunológica/genética , Linfocitos/inmunología , Anotación de Secuencia Molecular , Estrés Oxidativo , Intercambio Gaseoso Pulmonar , RNA-Seq , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria , Transcriptoma
19.
PLoS Biol ; 19(6): e3001306, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34170902

RESUMEN

Free-living bacteria adapt to environmental change by reprogramming gene expression through precise interactions of hundreds of DNA-binding proteins. A predictive understanding of bacterial physiology requires us to globally monitor all such protein-DNA interactions across a range of environmental and genetic perturbations. Here, we show that such global observations are possible using an optimized version of in vivo protein occupancy display technology (in vivo protein occupancy display-high resolution, IPOD-HR) and present a pilot application to Escherichia coli. We observe that the E. coli protein-DNA interactome organizes into 2 distinct prototypic features: (1) highly dynamic condition-dependent transcription factor (TF) occupancy; and (2) robust kilobase scale occupancy by nucleoid factors, forming silencing domains analogous to eukaryotic heterochromatin. We show that occupancy dynamics across a range of conditions can rapidly reveal the global transcriptional regulatory organization of a bacterium. Beyond discovery of previously hidden regulatory logic, we show that these observations can be utilized to computationally determine sequence specificity models for the majority of active TFs. Our study demonstrates that global observations of protein occupancy combined with statistical inference can rapidly and systematically reveal the transcriptional regulatory and structural features of a bacterial genome. This capacity is particularly crucial for non-model bacteria that are not amenable to routine genetic manipulation.


Asunto(s)
Cromosomas Bacterianos/metabolismo , Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Proteínas de Unión al ADN/metabolismo , Ambiente , Escherichia coli/genética , Regiones Promotoras Genéticas/genética , Unión Proteica , Factor sigma/metabolismo , Factores de Transcripción/química , Factores de Transcripción/metabolismo
20.
Nat Rev Microbiol ; 19(9): 553-566, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33981031

RESUMEN

Ruminants produce edible products and contribute to food security. They house a complex rumen microbial community that enables the host to digest their plant feed through microbial-mediated fermentation. However, the rumen microbiome is also responsible for the production of one of the most potent greenhouse gases, methane, and contributes about 18% of its total anthropogenic emissions. Conventional methods to lower methane production by ruminants have proved successful, but to a limited and often temporary extent. An increased understanding of the host-microbiome interactions has led to the development of new mitigation strategies. In this Review we describe the composition, ecology and metabolism of the rumen microbiome, and the impact on host physiology and the environment. We also discuss the most pertinent methane mitigation strategies that emerged to balance food security and environmental impacts.


Asunto(s)
Bacterias/clasificación , Ambiente , Seguridad Alimentaria , Microbioma Gastrointestinal/fisiología , Rumen/microbiología , Rumiantes/microbiología , Animales , Bacterias/metabolismo , Rumiantes/fisiología
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