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1.
Methods Mol Biol ; 2615: 267-280, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36807798

RESUMO

Defects in deoxyribonucleoside triphosphate (dNTP) metabolism are associated with a number of mitochondrial DNA (mtDNA) depletion syndromes (MDS). These disorders affect the muscles, liver, and brain, and the concentrations of dNTPs in these tissues are already normally low and are, therefore, difficult to measure. Thus, information about the concentrations of dNTPs in tissues of healthy animals and animals with MDS are important for mechanistic studies of mtDNA replication, analysis of disease progression, and the development of therapeutic interventions. Here, we present a sensitive method for the simultaneous analysis of all four dNTPs as well as all four ribonucleoside triphosphates (NTPs) in mouse muscles using hydrophilic interaction liquid chromatography coupled with triple quadrupole mass spectrometry. The simultaneous detection of NTPs allows them to be used as internal standards for the normalization of dNTP concentrations. The method can be applied for measuring dNTP and NTP pools in other tissues and organisms.


Assuntos
Nucleosídeos , Espectrometria de Massas em Tandem , Camundongos , Animais , Espectrometria de Massas em Tandem/métodos , Nucleotídeos , Cromatografia Líquida/métodos , DNA Mitocondrial/genética , Interações Hidrofóbicas e Hidrofílicas , Músculos
2.
J Am Coll Health ; : 1-7, 2023 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36701478

RESUMO

Objectives: This study examined the prevalence, patterns, and knowledge of Energy Drink (ED) consumption among undergraduate students. Participants: Participants included students (n = 373) attending a medium-sized rural university in Texas. Methods: Students were surveyed anonymously using convenience sampling and a cross-sectional design with 15 items structured questionnaire. Results: Nearly 90% of the study participants (N = 373) were between 18-24 years. Among the consumers (n = 165), the majority were females (80%) and Caucasian (73%). About 60% of them lived on campus, 22% were engaged in some type of sports activity, and primarily represented the freshmen (42%) and sophomore (25%) population. Having apriori knowledge of the negative health effects of EDs was associated with their consumption [OR: 0.40, CI: (0.22, 0.72)]. Conclusions: Our findings highlight the need to establish programs and policies on campus to address ED consumption issues and create educational campaigns to inform the undergraduate population attending a rural university.

3.
PLoS One ; 18(1): e0280962, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36719877

RESUMO

Seed priming is a simple and cost effective method to obtain a better plant stand under diverse environmental conditions. The current study was designed to determine the optimal priming duration and water volume for wheat seed. For this experiment, three wheat genotypes with distinct genetic and adaptive backgrounds were chosen. Seeds of each genotype were hydroprimed for 7 durations, i.e. 1, 2, 4, 8, 12, 16, and 20 hours, in three different water volumes, i.e. half, equal, and double volume with respect to seed weight and then surface dried for 1 hour. The control was unprimed (dry) seed. The germination characteristics and seedling vigour potential of hydroprimed seeds were evaluated in the lab by recording several parameters such as germination percentage and speed, seedling growth, and vigour indices at two different temperature levels. The results showed that optimal duration for hydropriming of wheat seed is 12 hours with an equal volume with respect to original seed weight, closely followed by 8 hours with double volume. Reduction in seed performance was observed at 16 and 20 hours priming particularly at double volume treatment. Effect of temperature on seed germination showed improvement in seedling vigour at 25°C when compared to 20°C, although effect on germination percentage was non-significant. Volume of water and priming duration showed significant interactive effects demonstrating that a higher volume can give equivalent results at a shorter duration and vice versa. Another experiment was also conducted to compare the on-farm priming (surface dried seed) with conventional priming (seed re-dried to original moisture) taking 3 potential durations i.e. 8, 12 and 16 hours. Results revealed that both priming methods were statistically at par in terms of germination percentage, while, surface drying resulted in better seedling vigour and speed of germination.


Assuntos
Triticum , Água , Água/farmacologia , Fazendas , Germinação , Plântula , Sementes
4.
Plant Physiol Biochem ; 194: 533-549, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36521290

RESUMO

The rapid population growth and environmental challenges in agriculture need innovative and sustainable solutions to meet the growing need for food worldwide. Recent nanotechnological advances found its broad applicability in agriculture's protection and post-harvesting. Engineered nanomaterials play a vital role in plant regulation, seed germination, and genetic manipulation. Their size, surface morphology, properties, and composition were designed for controlled release and enhanced properties in agriculture and the food industry. Nanoparticles can potentially be applied for the targeted and controlled delivery of fertilizers, pesticides, herbicides, plant growth regulators, etc. This help to eliminate the use of chemical-based pesticides and their water solubility, protect agrochemicals from breakdown and degradation, improve soil health, and naturally control crop pathogens, weeds, and insects, ultimately leading to enhanced crop growth and production capacity in the food industry. They can be effectively utilized for nano-encapsulation, seed germination, genetic manipulation, etc., for protecting plants and improving crop productivity, safe and improved food quality, and monitoring climate conditions. Nanoparticles played a crucial role in the uptake and translocation processes, genetically modifying the crops, high seed germination, and productivity. In this article, we have reviewed some important applications of nanoparticles for sustainable agro-food systems. The need and role of nanotechnology concerning challenges and problems faced by agriculture and the food industry are critically discussed, along with the limitations and future prospects of nanoparticles.


Assuntos
Nanopartículas , Praguicidas , Nanotecnologia , Agricultura , Nanopartículas/química , Praguicidas/química , Fertilizantes , Produtos Agrícolas
5.
Front Biosci (Landmark Ed) ; 27(11): 310, 2022 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-36472106

RESUMO

In the present era of climate change and global warming, high temperatures have increased considerably, posing a threat to plant life. Heat stress affects the biochemistry, physiology and molecular makeup of the plant by altering the key processes, i.e., photosynthesis, respiration and reproduction which reduces its growth and development. There is a dire need to manage this problem sustainably for plant conservation as well as the food security of the human population. Use of phytohormones to induce thermotolerance in plants can be a sustainable way to fight the adversities of heat stress. Phytohormone-induced thermotolerance proves to be a compelling approach to sustainably relieve the damaging effects of heat stress on plants. Salicylic acid (SA) is an essential molecule in biotic and abiotic defense response signal transduction pathways. When supplied externally, it imparts heat stress tolerance to the plants by different means, viz., increased Heat Shock Proteins (HSP) production, Reactive oxygen species (ROS) scavenging, protection of the reproductive system and enhancing photosynthetic efficiency. The effect of SA on plants is highly dependent on the concentration applied, plant species, plant age, type of tissues treated, and duration of the treatment. The present review paper summarizes the mechanism of thermotolerance induced by salicylic acid in plants under heat stress conditions. It includes the regulatory effects of SA on heat shock proteins, antioxidant metabolism, and maintenance of Ca2+ homeostasis under heat stress. This review combines the studies conducted to elucidate the role of SA in the modulation of different mechanisms which lead to heat stress tolerance in plants. It discusses the mechanism of SA in protecting the photosynthetic machinery and reproductive system during high-temperature stress.


Assuntos
Resposta ao Choque Térmico , Ácido Salicílico , Humanos , Ácido Salicílico/farmacologia , Fotossíntese , Antioxidantes/farmacologia , Proteínas de Choque Térmico/metabolismo , Proteínas de Choque Térmico/farmacologia , Estresse Fisiológico
6.
Cell Metab ; 34(12): 1895-1896, 2022 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-36476929

RESUMO

A recent publication reported a uniform ∼5- to 6-fold increase in dNTP pools 30 min after exposure to ionizing radiation. Das et al. were not able to reproduce these results. Their data instead agree with earlier publications reporting no increase in dNTP pools in mammalian cells in response to DNA damage.


Assuntos
Dano ao DNA
7.
Sci Rep ; 12(1): 20092, 2022 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-36418392

RESUMO

Current study signifies the use of nanoparticles as alternative in plant disease management to avoid harmful effect of pesticide and fungicide residue. Synthesis of nanoparticles (Ni0.5Al0.5Fe2O4) by hydrothermal method and studied their X-ray diffraction analysis (XRD), Raman spectra, and UV spectra and further successfully evaluated for antifungal activity against a soil and seed borne pathogenic fungus (Fusarium oxysporum).Among various pests, fungal pathogens are the main cause of crop destruction and we developed nanoparticles (Ni0.5Al0.5Fe2O4) which is successfully evaluated for antimycotic activity against dry rot (F. oxysporum) of ginger which causes 50-70% losses in the ginger plant. In vitro and in vivo analysis designated that the nanoparticles (Ni0.5Al0.5Fe2O4) has shown an excellent antifungal activity against F. oxysporum at 0.5 mg/ml concentration. Similarly, no disease incidence was recorded when Ni0.5Al0.5Fe2O4 nanoparticles used at 0.5 mg/ml concentration under in vivo conditions. In plants various environmental stresses (biotic and abiotic) leads to excessive production of reactive oxygen species (ROS) causing progressive oxidative damage and ultimately leads to cell death. The role of ROS in nanoparticles (Ni0.5Al0.5Fe2O4) represents by reduction in the growth inhibition of F. oxysporum. We speculated in light of these results that the cytotoxic effect of Ni0.5Al0.5Fe2O4 nanoparticles on F. oxysporum may be mediated through ROS. We can suggest the role of nanoparticles (Ni0.5Al0.5Fe2O4) gives a promising result as a fungicidal activity and could be a novel family of future new generation fungicide.


Assuntos
Fungicidas Industriais , Gengibre , Nanopartículas , Gengibre/metabolismo , Antifúngicos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Fungicidas Industriais/farmacologia
8.
Psychol Health Med ; : 1-8, 2022 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-36120800

RESUMO

The Covid-19 pandemic, which was declared a public health emergency on 30 January 2020, has made it crucial for humans to learn how to behave to control the pandemic's spread. Policymakers must assess human behaviour and their responses to pandemic breakouts to develop a strategy for limiting pandemics and their harm to society at large. The present study applying exploratory factor analysis assessed five aspects of human behaviour regarding Covid-19, namely compliance behaviour, avoidance behaviour, protective behaviour, informed behaviour, and risk perception. The study applying hierarchical regression discovered that by combining informed, protective, and avoidance behaviour, people can be convinced to embrace the compliance behaviour required by public authorities. Furthermore, higher risk perception also positively moderates the relationship between information and compliance behaviour.

9.
Life Sci Alliance ; 5(4)2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35017203

RESUMO

Eukaryotic cells have evolved a replication stress response that helps to overcome stalled/collapsed replication forks and ensure proper DNA replication. The replication checkpoint protein Mrc1 plays important roles in these processes, although its functional interactions are not fully understood. Here, we show that MRC1 negatively interacts with CHL1, which encodes the helicase protein Chl1, suggesting distinct roles for these factors during the replication stress response. Indeed, whereas Mrc1 is known to facilitate the restart of stalled replication forks, we uncovered that Chl1 controls replication fork rate under replication stress conditions. Chl1 loss leads to increased RNR1 gene expression and dNTP levels at the onset of S phase likely without activating the DNA damage response. This in turn impairs the formation of RPA-coated ssDNA and subsequent checkpoint activation. Thus, the Chl1 helicase affects RPA-dependent checkpoint activation in response to replication fork arrest by ensuring proper intracellular dNTP levels, thereby controlling replication fork progression under replication stress conditions.


Assuntos
Proteínas de Ciclo Celular/genética , Proteínas Cromossômicas não Histona/genética , Replicação do DNA/genética , Desoxirribonucleotídeos/genética , Proteínas de Saccharomyces cerevisiae/genética , Células Cultivadas , RNA Helicases DEAD-box , DNA Helicases , Desoxirribonucleotídeos/metabolismo , Humanos
10.
DNA Repair (Amst) ; 110: 103272, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35038632

RESUMO

DNA replication is performed by replisome proteins, which are highly conserved from yeast to humans. The CMG [Cdc45-Mcm2-7-GINS(Psf1-3, Sld5)] helicase unwinds the double helix to separate the leading and lagging DNA strands, which are replicated by the specialized DNA polymerases epsilon (Pol ε) and delta (Pol δ), respectively. This division of labor was confirmed by both genetic analyses and in vitro studies. Exceptions from this rule were described mainly in cells with impaired catalytic polymerase ε subunit. The central role in the recruitment and establishment of Pol ε on the leading strand is played by the CMG complex assembled on DNA during replication initiation. In this work we analyzed the consequences of impaired functioning of the CMG complex for the division labor between DNA polymerases on the two replicating strands. We showed in vitro that the GINSPsf1-1 complex poorly bound the Psf3 subunit. In vivo, we observed increased rates of L612M Pol δ-specific mutations during replication of the leading DNA strand in psf1-1 cells. These findings indicated that defective functioning of GINS impaired leading strand replication by Pol ε and necessitated involvement of Pol δ in the synthesis on this strand with a possible impact on the distribution of mutations and genomic stability. These are the first results to imply that the division of labor between the two main replicases can be severely influenced by a defective nonpolymerase subunit of the replisome.


Assuntos
Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , DNA/metabolismo , DNA Helicases/metabolismo , DNA Polimerase II/metabolismo , DNA Polimerase III/genética , DNA Polimerase III/metabolismo , Replicação do DNA , Humanos , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
11.
Nucleic Acids Res ; 50(3): e18, 2022 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-34850106

RESUMO

Information about the cellular concentrations of deoxyribonucleoside triphosphates (dNTPs) is instrumental for mechanistic studies of DNA replication and for understanding diseases caused by defects in dNTP metabolism. The dNTPs are measured by methods based on either HPLC or DNA polymerization. An advantage with the HPLC-based techniques is that the parallel analysis of ribonucleoside triphosphates (rNTPs) can serve as an internal quality control of nucleotide integrity and extraction efficiency. We have developed a Freon-free trichloroacetic acid-based method to extract cellular nucleotides and an isocratic reverse phase HPLC-based technique that is able to separate dNTPs, rNTPs and ADP in a single run. The ability to measure the ADP levels improves the control of nucleotide integrity, and the use of an isocratic elution overcomes the shifting baseline problems in previously developed gradient-based reversed phase protocols for simultaneously measuring dNTPs and rNTPs. An optional DNA-polymerase-dependent step is used for confirmation that the dNTP peaks do not overlap with other components of the extracts, further increasing the reliability of the analysis. The method is compatible with a wide range of biological samples and has a sensitivity better than other UV-based HPLC protocols, closely matching that of mass spectrometry-based detection.


Assuntos
Cromatografia Líquida de Alta Pressão , Desoxirribonucleotídeos , Ribonucleotídeos/análise , Difosfato de Adenosina , Cromatografia Líquida de Alta Pressão/métodos , DNA , Desoxirribonucleotídeos/análise , Reprodutibilidade dos Testes
12.
Explore (NY) ; 17(2): 115-121, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32249198

RESUMO

Studies have reported the benefits of music-listening in stress-reduction using musical pieces of specific scale or 'Raaga'. But the influence of lower-level musical properties (like tempo, octave, timbre, etc.) lack research backing. Carnatic music concerts use incremental modulations in tempo and octave (e.g.: 'Ragam-Tanam-Pallavi') to elevate the mood of audiences. Therefore, the current study aimed to examine the anxiolytic effect of this musical property. A randomised controlled cross-over study with 21 male undergraduate medical students was followed. 11 participants listened to 'Varying music' (VM: instrumental music with incremental variations in tempo and octave) and 10 listened to 'Stable music' (SM: instrumental music without such variations), thrice daily for 6 days, both clips recorded in Raaga-Kaapi and silence being the control intervention. Electroencephalography (EEG) and Electrocardiography (for heart rate variability or HRV) were done on all 6 days. Beck's Anxiety inventory and State-trait anxiety scale were administered on Day-1 and Day-6. A significant anxiety score reduction was seen only in VM. VM showed marked decrease in lower frequency EEG power in bilateral temporo-parieto-occipital regions compared to silence, whereas SM showed increase in higher frequencies. Relatively, VM showed more midline power reduction (i.e., lower default mode network or DMN activity) and SM showed greater left-dominant alpha/beta asymmetry (i.e., greater right brain activation). During both music interventions HRV remained stable, unlike silence intervention. We speculate that, gradual transition between lower-slower and higher-faster music portions of VM induces a 'controlled-mind wandering' state involving balanced switching between heightened mind wandering ('attention to self') and reduced mind wandering ('attention to music') states, respectively. Therefore, music-selection has remarkable influence on stress-management and warrants further research.


Assuntos
Música , Ansiedade/terapia , Percepção Auditiva , Estudos Cross-Over , Eletroencefalografia , Humanos , Masculino
14.
Proc Natl Acad Sci U S A ; 117(25): 14306-14313, 2020 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-32513727

RESUMO

Ribonucleotides (rNMPs) incorporated in the nuclear genome are a well-established threat to genome stability and can result in DNA strand breaks when not removed in a timely manner. However, the presence of a certain level of rNMPs is tolerated in mitochondrial DNA (mtDNA) although aberrant mtDNA rNMP content has been identified in disease models. We investigated the effect of incorporated rNMPs on mtDNA stability over the mouse life span and found that the mtDNA rNMP content increased during early life. The rNMP content of mtDNA varied greatly across different tissues and was defined by the rNTP/dNTP ratio of the tissue. Accordingly, mtDNA rNMPs were nearly absent in SAMHD1-/- mice that have increased dNTP pools. The near absence of rNMPs did not, however, appreciably affect mtDNA copy number or the levels of mtDNA molecules with deletions or strand breaks in aged animals near the end of their life span. The physiological rNMP load therefore does not contribute to the progressive loss of mtDNA quality that occurs as mice age.


Assuntos
DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Instabilidade Genômica/fisiologia , Ribonucleotídeos/genética , Ribonucleotídeos/metabolismo , Animais , Dano ao DNA , Feminino , Dosagem de Genes , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Nucleotídeos , Proteína 1 com Domínio SAM e Domínio HD/genética
15.
Cell Rep ; 31(6): 107640, 2020 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-32402273

RESUMO

The anti-leukemia agent forodesine causes cytotoxic overload of intracellular deoxyguanosine triphosphate (dGTP) but is efficacious only in a subset of patients. We report that SAMHD1, a phosphohydrolase degrading deoxyribonucleoside triphosphate (dNTP), protects cells against the effects of dNTP imbalances. SAMHD1-deficient cells induce intrinsic apoptosis upon provision of deoxyribonucleosides, particularly deoxyguanosine (dG). Moreover, dG and forodesine act synergistically to kill cells lacking SAMHD1. Using mass cytometry, we find that these compounds kill SAMHD1-deficient malignant cells in patients with chronic lymphocytic leukemia (CLL). Normal cells and CLL cells from patients without SAMHD1 mutation are unaffected. We therefore propose to use forodesine as a precision medicine for leukemia, stratifying patients by SAMHD1 genotype or expression.


Assuntos
Nucleotídeos de Desoxiguanina/metabolismo , Nucleosídeos de Purina/farmacologia , Pirimidinonas/farmacologia , Proteína 1 com Domínio SAM e Domínio HD/metabolismo , Animais , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Masculino , Camundongos , Camundongos Endogâmicos C57BL
16.
Mol Cell ; 78(3): 396-410.e4, 2020 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-32169162

RESUMO

The Mec1 and Rad53 kinases play a central role during acute replication stress in budding yeast. They are also essential for viability in normal growth conditions, but the signal that activates the Mec1-Rad53 pathway in the absence of exogenous insults is currently unknown. Here, we show that this pathway is active at the onset of normal S phase because deoxyribonucleotide triphosphate (dNTP) levels present in G1 phase may not be sufficient to support processive DNA synthesis and impede DNA replication. This activation can be suppressed experimentally by increasing dNTP levels in G1 phase. Moreover, we show that unchallenged cells entering S phase in the absence of Rad53 undergo irreversible fork collapse and mitotic catastrophe. Together, these data indicate that cells use suboptimal dNTP pools to detect the onset of DNA replication and activate the Mec1-Rad53 pathway, which in turn maintains functional forks and triggers dNTP synthesis, allowing the completion of DNA replication.


Assuntos
Replicação do DNA/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Fase S/fisiologia , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Quinase do Ponto de Checagem 2/genética , Quinase do Ponto de Checagem 2/metabolismo , Desoxirribonucleotídeos/genética , Desoxirribonucleotídeos/metabolismo , Regulação Fúngica da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intracelular/genética , Mitose , Proteínas Serina-Treonina Quinases/genética , Origem de Replicação , Saccharomyces cerevisiae/citologia , Proteínas de Saccharomyces cerevisiae/genética
17.
Nucleic Acids Res ; 48(8): 4274-4297, 2020 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-32187369

RESUMO

Cellular levels of ribonucleoside triphosphates (rNTPs) are much higher than those of deoxyribonucleoside triphosphates (dNTPs), thereby influencing the frequency of incorporation of ribonucleoside monophosphates (rNMPs) by DNA polymerases (Pol) into DNA. RNase H2-initiated ribonucleotide excision repair (RER) efficiently removes single rNMPs in genomic DNA. However, processing of rNMPs by Topoisomerase 1 (Top1) in absence of RER induces mutations and genome instability. Here, we greatly increased the abundance of genomic rNMPs in Saccharomyces cerevisiae by depleting Rnr1, the major subunit of ribonucleotide reductase, which converts ribonucleotides to deoxyribonucleotides. We found that in strains that are depleted of Rnr1, RER-deficient, and harbor an rNTP-permissive replicative Pol mutant, excessive accumulation of single genomic rNMPs severely compromised growth, but this was reversed in absence of Top1. Thus, under Rnr1 depletion, limited dNTP pools slow DNA synthesis by replicative Pols and provoke the incorporation of high levels of rNMPs in genomic DNA. If a threshold of single genomic rNMPs is exceeded in absence of RER and presence of limited dNTP pools, Top1-mediated genome instability leads to severe growth defects. Finally, we provide evidence showing that accumulation of RNA/DNA hybrids in absence of RNase H1 and RNase H2 leads to cell lethality under Rnr1 depletion.


Assuntos
DNA Topoisomerases Tipo I/metabolismo , Ribonucleotídeo Redutases/genética , Ribonucleotídeos/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Dano ao DNA , Desoxirribonucleotídeos/metabolismo , Genoma Fúngico , Instabilidade Genômica , Mutação , Ribonuclease H/genética , Ribonucleases/genética , Pontos de Checagem da Fase S do Ciclo Celular , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/metabolismo , Deleção de Sequência
18.
Sci Total Environ ; 714: 136798, 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-31986391

RESUMO

Livestock depredation is the most ubiquitous type of negative interaction between humans and carnivores. We conducted a range-wide assessment linking diet patterns of the endangered dhole Cuon alpinus, with livestock consumption and human-dhole interactions. We first performed a reanalysis of dhole diet data from all published studies (1973-2013) incorporating a recently-developed non-linear correction factor for quantifying prey biomass consumed. We then determined the relative livestock numbers consumed by dholes over time across its range, compared these with earlier estimates, and investigated the relative importance of wild vs. non-wild prey in dhole diet. Using information from >70 studies, we explored links between livestock consumption by dholes, availability of wild versus non-wild prey, sympatric depredation-prone carnivores, and people's perception of dholes as livestock predators. We found that (a) dhole diet profiles varied regionally, (b) dholes consumed fewer livestock compared to estimates generated using other, widely used methods, (c) livestock consumption by dholes was associated with wild and non-wild prey densities, and number of co-predator species, and (d) people's negative perception of dholes was associated with pack sizes, levels of livestock depredation and number of sympatric carnivore species. Global efforts for dhole conservation should involve different strategies based on region-specific realities that account for ecological context as well as human perceptions, which would require well-designed studies of dhole social and population dynamics, and human-dhole interactions. We also call for more such range-wide assessments of livestock depredation by wild canids, complemented with direct investigations of human-canid interactions.


Assuntos
Carnívoros , Gado , Animais , Biomassa , Dieta , Cães , Humanos , Comportamento Predatório
19.
Nucleic Acids Res ; 48(1): 264-277, 2020 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-31647103

RESUMO

The accumulation of mutations is frequently associated with alterations in gene function leading to the onset of diseases, including cancer. Aiming to find novel genes that contribute to the stability of the genome, we screened the Saccharomyces cerevisiae deletion collection for increased mutator phenotypes. Among the identified genes, we discovered MET7, which encodes folylpolyglutamate synthetase (FPGS), an enzyme that facilitates several folate-dependent reactions including the synthesis of purines, thymidylate (dTMP) and DNA methylation. Here, we found that Met7-deficient strains show elevated mutation rates, but also increased levels of endogenous DNA damage resulting in gross chromosomal rearrangements (GCRs). Quantification of deoxyribonucleotide (dNTP) pools in cell extracts from met7Δ mutant revealed reductions in dTTP and dGTP that cause a constitutively active DNA damage checkpoint. In addition, we found that the absence of Met7 leads to dUTP accumulation, at levels that allowed its detection in yeast extracts for the first time. Consequently, a high dUTP/dTTP ratio promotes uracil incorporation into DNA, followed by futile repair cycles that compromise both mitochondrial and nuclear DNA integrity. In summary, this work highlights the importance of folate polyglutamylation in the maintenance of nucleotide homeostasis and genome stability.


Assuntos
Nucleotídeos de Desoxiuracil/metabolismo , Ácido Fólico/metabolismo , Genoma Fúngico , Peptídeo Sintases/genética , Saccharomyces cerevisiae/genética , Nucleotídeos de Timina/metabolismo , Núcleo Celular/genética , Núcleo Celular/metabolismo , Dano ao DNA , DNA Fúngico/genética , DNA Fúngico/metabolismo , Nucleotídeos de Desoxiguanina/metabolismo , Deleção de Genes , Regulação Fúngica da Expressão Gênica , Instabilidade Genômica , Mitocôndrias/genética , Mitocôndrias/metabolismo , Mutação , Peptídeo Sintases/deficiência , Saccharomyces cerevisiae/metabolismo , Uracila/metabolismo
20.
J Aging Health ; 32(5-6): 328-339, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30614341

RESUMO

Objective: Given that one in four older adults suffer potentially preventable falls annually, we aimed to identify areas with (a) delivery gaps of evidence-based programs (EBPs) targeting fall prevention among older adults, namely A Matter of Balance (AMOB), and (b) high rates of fall-related hospitalizations-hotspots. Method: Analyses included multiple geospatially linked datasets. Results: EBPs were delivered ≥1 time in 84 counties in 2012 and 90 counties in 2014. Factors associated with EPB delivery gaps (absence; p<.05) included high-density older adult areas, non-fall-related hospitalization hotspots, lower population density, nonmetropolitan areas, high-density Hispanic adult areas, and areas with limited access to home health care agencies. Hotspots for fall-related hospitalization numbered 64 in 2012 and 62 in 2014. Factors associated with hotspots included low-density older adult areas, having AMOB delivered ≥1 time annually, high population density, and high-density Hispanic adult areas. Discussion: In resource-finite settings (e.g., the aging services sector), identifying high priority areas allows for precise allocation of limited resources.


Assuntos
Acidentes por Quedas/prevenção & controle , Acidentes por Quedas/estatística & dados numéricos , Atenção à Saúde/tendências , Necessidades e Demandas de Serviços de Saúde/tendências , Hospitalização/tendências , Idoso , Envelhecimento , Atenção à Saúde/métodos , Etnicidade/estatística & dados numéricos , Humanos , Pobreza , Texas
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