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1.
Nature ; 627(8004): 564-571, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38418889

RESUMO

Numerous studies have shown reduced performance in plants that are surrounded by neighbours of the same species1,2, a phenomenon known as conspecific negative density dependence (CNDD)3. A long-held ecological hypothesis posits that CNDD is more pronounced in tropical than in temperate forests4,5, which increases community stabilization, species coexistence and the diversity of local tree species6,7. Previous analyses supporting such a latitudinal gradient in CNDD8,9 have suffered from methodological limitations related to the use of static data10-12. Here we present a comprehensive assessment of latitudinal CNDD patterns using dynamic mortality data to estimate species-site-specific CNDD across 23 sites. Averaged across species, we found that stabilizing CNDD was present at all except one site, but that average stabilizing CNDD was not stronger toward the tropics. However, in tropical tree communities, rare and intermediate abundant species experienced stronger stabilizing CNDD than did common species. This pattern was absent in temperate forests, which suggests that CNDD influences species abundances more strongly in tropical forests than it does in temperate ones13. We also found that interspecific variation in CNDD, which might attenuate its stabilizing effect on species diversity14,15, was high but not significantly different across latitudes. Although the consequences of these patterns for latitudinal diversity gradients are difficult to evaluate, we speculate that a more effective regulation of population abundances could translate into greater stabilization of tropical tree communities and thus contribute to the high local diversity of tropical forests.


Assuntos
Biodiversidade , Florestas , Mapeamento Geográfico , Árvores , Modelos Biológicos , Especificidade da Espécie , Árvores/classificação , Árvores/fisiologia , Clima Tropical
2.
Cell ; 158(3): 633-46, 2014 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-25083873

RESUMO

ATR controls chromosome integrity and chromatin dynamics. We have previously shown that yeast Mec1/ATR promotes chromatin detachment from the nuclear envelope to counteract aberrant topological transitions during DNA replication. Here, we provide evidence that ATR activity at the nuclear envelope responds to mechanical stress. Human ATR associates with the nuclear envelope during S phase and prophase, and both osmotic stress and mechanical stretching relocalize ATR to nuclear membranes throughout the cell cycle. The ATR-mediated mechanical response occurs within the range of physiological forces, is reversible, and is independent of DNA damage signaling. ATR-defective cells exhibit aberrant chromatin condensation and nuclear envelope breakdown. We propose that mechanical forces derived from chromosome dynamics and torsional stress on nuclear membranes activate ATR to modulate nuclear envelope plasticity and chromatin association to the nuclear envelope, thus enabling cells to cope with the mechanical strain imposed by these molecular processes.


Assuntos
Membrana Nuclear/metabolismo , Estresse Mecânico , Animais , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Pontos de Checagem do Ciclo Celular , Linhagem Celular Tumoral , Quinase 1 do Ponto de Checagem , Cromatina/metabolismo , Fibroblastos/citologia , Fibroblastos/metabolismo , Células HeLa , Humanos , Camundongos , Células NIH 3T3 , Osmose , Proteínas Quinases/metabolismo
3.
PLoS Genet ; 20(2): e1011158, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38359090

RESUMO

Elucidating gene function is a major goal in biology, especially among non-model organisms. However, doing so is complicated by the fact that molecular conservation does not always mirror functional conservation, and that complex relationships among genes are responsible for encoding pathways and higher-order biological processes. Co-expression, a promising approach for predicting gene function, relies on the general principal that genes with similar expression patterns across multiple conditions will likely be involved in the same biological process. For Cryptococcus neoformans, a prevalent human fungal pathogen greatly diverged from model yeasts, approximately 60% of the predicted genes in the genome lack functional annotations. Here, we leveraged a large amount of publicly available transcriptomic data to generate a C. neoformans Co-Expression Network (CryptoCEN), successfully recapitulating known protein networks, predicting gene function, and enabling insights into the principles influencing co-expression. With 100% predictive accuracy, we used CryptoCEN to identify 13 new DNA damage response genes, underscoring the utility of guilt-by-association for determining gene function. Overall, co-expression is a powerful tool for uncovering gene function, and decreases the experimental tests needed to identify functions for currently under-annotated genes.


Assuntos
Criptococose , Cryptococcus neoformans , Humanos , Cryptococcus neoformans/genética , Criptococose/genética , Criptococose/microbiologia , Reparo do DNA/genética , Fenótipo , Dano ao DNA/genética , Proteínas Fúngicas/genética
4.
Nature ; 580(7802): 227-231, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32269351

RESUMO

Atmospheric carbon dioxide enrichment (eCO2) can enhance plant carbon uptake and growth1-5, thereby providing an important negative feedback to climate change by slowing the rate of increase of the atmospheric CO2 concentration6. Although evidence gathered from young aggrading forests has generally indicated a strong CO2 fertilization effect on biomass growth3-5, it is unclear whether mature forests respond to eCO2 in a similar way. In mature trees and forest stands7-10, photosynthetic uptake has been found to increase under eCO2 without any apparent accompanying growth response, leaving the fate of additional carbon fixed under eCO2 unclear4,5,7-11. Here using data from the first ecosystem-scale Free-Air CO2 Enrichment (FACE) experiment in a mature forest, we constructed a comprehensive ecosystem carbon budget to track the fate of carbon as the forest responded to four years of eCO2 exposure. We show that, although the eCO2 treatment of +150 parts per million (+38 per cent) above ambient levels induced a 12 per cent (+247 grams of carbon per square metre per year) increase in carbon uptake through gross primary production, this additional carbon uptake did not lead to increased carbon sequestration at the ecosystem level. Instead, the majority of the extra carbon was emitted back into the atmosphere via several respiratory fluxes, with increased soil respiration alone accounting for half of the total uptake surplus. Our results call into question the predominant thinking that the capacity of forests to act as carbon sinks will be generally enhanced under eCO2, and challenge the efficacy of climate mitigation strategies that rely on ubiquitous CO2 fertilization as a driver of increased carbon sinks in global forests.


Assuntos
Atmosfera/química , Dióxido de Carbono/análise , Dióxido de Carbono/metabolismo , Sequestro de Carbono , Florestas , Árvores/metabolismo , Biomassa , Eucalyptus/crescimento & desenvolvimento , Eucalyptus/metabolismo , Aquecimento Global/prevenção & controle , Modelos Biológicos , New South Wales , Fotossíntese , Solo/química , Árvores/crescimento & desenvolvimento
5.
Hum Mol Genet ; 32(5): 709-719, 2023 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-35899434

RESUMO

Childhood socioeconomic position (SEP) is a major determinant of health and well-being across the entire life course. To effectively prevent and reduce health risks related to SEP, it is critical to better understand when and under what circumstances socioeconomic adversity shapes biological processes. DNA methylation (DNAm) is one such mechanism for how early life adversity 'gets under the skin'. In this study, we evaluated the dynamic relationship between SEP and DNAm across childhood using data from 946 mother-child pairs in the Avon Longitudinal Study of Parents and Children. We assessed six SEP indicators spanning financial, occupational and residential domains during very early childhood (ages 0-2), early childhood (ages 3-5) and middle childhood (ages 6-7). Epigenome-wide DNAm was measured at 412 956 cytosine-guanines (CpGs) from peripheral blood at age 7. Using an innovative two-stage structured life-course modeling approach, we tested three life-course hypotheses for how SEP shapes DNAm profiles-accumulation, sensitive period and mobility. We showed that changes in the socioeconomic environment were associated with the greatest differences in DNAm, and that middle childhood may be a potential sensitive period when socioeconomic instability is especially important in shaping DNAm. Top SEP-related DNAm CpGs were overrepresented in genes involved in pathways important for neural development, immune function and metabolic processes. Our findings highlight the importance of socioeconomic stability during childhood and if replicated, may emphasize the need for public programs to help children and families experiencing socioeconomic instability and other forms of socioeconomic adversity.


Assuntos
Metilação de DNA , Genoma , Criança , Humanos , Pré-Escolar , Recém-Nascido , Lactente , Estudos Longitudinais , Fatores Socioeconômicos , Epigenoma , Epigênese Genética
6.
Brain ; 2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39001866

RESUMO

Mitochondrial and synaptic dysfunction are pathological features of brain aging and cognitive decline. Synaptic mitochondria are vital for meeting the high energy demands of synaptic transmission. However, little is known about the link between age-related metabolic changes and the integrity of synaptic mitochondria. To this end, we investigate the mechanisms of advanced glycation endproducts (AGEs)-mediated mitochondrial and synaptic stress and evaluate the strategies to eliminate these toxic metabolites. Using aged brain and novel transgenic mice overexpressing neuronal glyoxalase 1 (GLO1), we comprehensively analyzed alterations in accumulation/buildup of AGEs and related metabolites in synaptic mitochondria and the association of AGE levels with mitochondrial function. We demonstrate for the first time that synaptic mitochondria are an early and major target of AGEs and the related toxic metabolite methylglyoxal (MG), a precursor of AGEs. MG/AGEs-insulted synaptic mitochondria exhibit deterioration of mitochondrial and synaptic function. Such accumulation of MG/AGEs positively correlated with mitochondrial perturbation and oxidative stress in aging brain. Importantly, clearance of AGEs-related metabolites by enhancing neuronal GLO1, a key enzyme for detoxification/of AGEs, reduces synaptic mitochondrial AGEs accumulation and improves mitochondrial and cognitive function in aging and AGE-challenged mice. Furthermore, we evaluated the direct effect of AGEs on synaptic function in hippocampal neurons in live brain slices as an ex-vivo model and in vitro cultured hippocampal neurons by recording long-term potentiation (LTP) and measuring spontaneously occurring miniature excitatory postsynaptic currents (mEPSCs). Neuronal GLO1 rescues deficits in AGEs-induced synaptic plasticity and transmission by fully recovery of decline in LTP or frequency of mEPSC. These studies explore crosstalk between synaptic mitochondrial dysfunction and age-related metabolic changes relevant to brain aging and cognitive decline. Synaptic mitochondria are particularly susceptible to AGEs-induced damage, highlighting the central importance of synaptic mitochondrial dysfunction in synaptic degeneration in age-related cognitive decline. Thus, augmenting GLO1 function to scavenge toxic metabolites represents a therapeutic approach to reduce age-related AGEs accumulation and to improve mitochondrial function and learning and memory.

7.
PLoS Genet ; 18(11): e1010525, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36441813

RESUMO

Saccharomyces genomes are highly collinear and show relatively little structural variation, both within and between species of this yeast genus. We investigated the only common inversion polymorphism known in S. cerevisiae, which affects a 24-kb 'flip/flop' region containing 15 genes near the centromere of chromosome XIV. The region exists in two orientations, called reference (REF) and inverted (INV). Meiotic recombination in this region is suppressed in crosses between REF and INV orientation strains such as the BY x RM cross. We find that the inversion polymorphism is at least 17 million years old because it is conserved across the genus Saccharomyces. However, the REF and INV isomers are not ancient alleles but are continually being re-created by re-inversion of the region within each species. Inversion occurs due to continual homogenization of two almost identical 4-kb sequences that form an inverted repeat (IR) at the ends of the flip/flop region. The IR consists of two pairs of genes that are specifically and strongly expressed during the late stages of sporulation. We show that one of these gene pairs, YNL018C/YNL034W, codes for a protein that is essential for spore formation. YNL018C and YNL034W are the founder members of a gene family, Centroid, whose members in other Saccharomycetaceae species evolve fast, duplicate frequently, and are preferentially located close to centromeres. We tested the hypothesis that Centroid genes are a meiotic drive system, but found no support for this idea.


Assuntos
Saccharomyces , Saccharomyces/genética , Saccharomyces cerevisiae/genética
8.
Am J Physiol Cell Physiol ; 327(3): C571-C586, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38981605

RESUMO

Glutamine is a critical amino acid that serves as an energy source, building block, and signaling molecule for the heart tissue and the immune system. However, the role of glutamine metabolism in regulating cardiac remodeling following myocardial infarction (MI) is unknown. In this study, we show in adult male mice that glutamine metabolism is altered both in the remote (contractile) area and in infiltrating macrophages in the infarct area after permanent left anterior descending artery occlusion. We found that metabolites related to glutamine metabolism were differentially altered in macrophages at days 1, 3, and 7 after MI using untargeted metabolomics. Glutamine metabolism in live cells was increased after MI relative to no MI controls. Gene expression in the remote area of the heart indicated a loss of glutamine metabolism. Glutamine administration improved left ventricle (LV) function at days 1, 3, and 7 after MI, which was associated with improved contractile and metabolic gene expression. Conversely, administration of BPTES, a pharmacological inhibitor of glutaminase-1, worsened LV function after MI. Neither glutamine nor BPTES administration impacted gene expression or bioenergetics of macrophages isolated from the infarct area. Our results indicate that glutamine metabolism plays a critical role in maintaining LV contractile function following MI and that glutamine administration improves LV function. Glutamine metabolism may also play a role in regulating macrophage function, but macrophages are not responsive to exogenous pharmacological manipulation of glutamine metabolism.NEW & NOTEWORTHY Glutamine metabolism is altered in both infarct macrophages and the remote left ventricle (LV) following myocardial infarction (MI). Supplemental glutamine improves LV function following MI while inhibiting glutamine metabolism with BPTES worsens LV function. Supplemental glutamine or BPTES does not impact macrophage immunometabolic phenotypes after MI.


Assuntos
Glutamina , Macrófagos , Camundongos Endogâmicos C57BL , Infarto do Miocárdio , Função Ventricular Esquerda , Animais , Glutamina/metabolismo , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Macrófagos/metabolismo , Macrófagos/imunologia , Masculino , Função Ventricular Esquerda/efeitos dos fármacos , Camundongos , Remodelação Ventricular/efeitos dos fármacos , Glutaminase/metabolismo , Glutaminase/antagonistas & inibidores , Glutaminase/genética , Miocárdio/metabolismo , Miocárdio/patologia , Miocárdio/imunologia , Inflamação/metabolismo , Inflamação/patologia , Metabolismo Energético/efeitos dos fármacos
9.
Artigo em Inglês | MEDLINE | ID: mdl-38269408

RESUMO

Diabetes (DM) and hypertension (HTN) are major risk factors for chronic kidney injury, together accounting for >70% of end-stage renal disease. The combination of DM and HTN significantly accelerates development of renal injury; however, the underlying mechanisms of this synergy are still poorly understood. This study assessed whether mitochondria (MT) dysfunction is essential in developing renal injury in a rat model with combined DM and HTN. Type 1 DM was induced in Wistar rats by streptozotocin (STZ). HTN was induced six weeks later by inter-renal aorta constriction between the renal arteries, so that right kidneys were exposed to HTN while left kidneys were exposed to normotension. Kidneys exposed to DM or HTN alone had only mild glomerular injury and urinary albumin excretion (UAE). In contrast, kidneys exposed to DM plus 8 weeks HTN had significantly increased UAE and glomerular structural damage with reduced glomerular filtration rate. Marked increases in MT-derived reactive oxygen species (ROS) were also observed in right kidneys exposed to HTN+DM. We further tested whether treatment with MT-targeted antioxidant (MitoTEMPO) after the onset of HTN attenuates renal injury in rats with DM+HTN. Results show that kidneys in DM+AC+MitoTEMPO rats had lower UAE, less glomerular damage, and preserved MT function compared to untreated DM+AC rats. Our studies indicate that MT-derived ROS play a major role in promoting kidney dysfunction when DM is combined with HTN. Preserving MT function might be a potential therapeutic approach to halt the development of renal injury when DM coexists with HTN.

10.
Artigo em Inglês | MEDLINE | ID: mdl-39361725

RESUMO

In the present study we examined whether chronic intracerebroventricular (ICV) leptin administration protects against ischemia/reperfusion (I/R)-induced acute kidney injury (AKI). Twelve-week-old male rats were implanted with an ICV cannula into the right lateral ventricle and 8-10 days after surgery, leptin (0.021 mg/hr, n=8) or saline vehicle (0.5 ml/h, n=8) was infused via osmotic minipump connected to the ICV cannula for 12 days. On day 8 of leptin or vehicle infusion, rats were submitted to unilateral ischemia/reperfusion (UIR) by clamping the left pedicle for 30 min. To control for leptin-induced reductions in food intake, the vehicle-treated group was pair-fed (UIR-PF) to match the same amount of food consumed by leptin-treated (UIR-Leptin) rats. On the 12th day of leptin or vehicle infusion (4th day after AKI), single-left kidney glomerular filtration rate (GFR) was measured, blood samples were collected to quantify white blood cells, and kidneys were collected for histological assessment of injury. UIR-Leptin treated rats showed reduced right and left kidney weights (right: 1040±24 vs. 1281±36 mg; left: 1127±71 vs. 1707±45 mg, for UIR-Leptin and UIR-PF, respectively). ICV leptin infusion improved GFR (0.50±0.06 vs. 0.13±0.03 ml/min/g KW) and reduced kidney injury scores. ICV leptin treatment also attenuated the reduction in circulating adiponectin levels that was observed in UIR-PF rats, and increased circulating white blood cells count compared to UIR-PF rats (16.3±1.3 vs. 9.8±0.6 k/mL). Therefore, we show that leptin, via its actions on the central nervous system, confers significant protection against major kidney dysfunction and injury in a model of ischemia/reperfusion-induced AKI.

11.
Am J Physiol Renal Physiol ; 326(5): F727-F736, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38511219

RESUMO

Although obesity is recognized as a risk factor for cardiorenal and metabolic diseases, the impact of parental obesity on the susceptibility of their offspring to renal injury at adulthood is unknown. We examined the impact of parental obesity on offspring kidney function, morphology, and markers of kidney damage after acute kidney injury (AKI). Offspring from normal (N) diet-fed C57BL/6J parents were fed either N (NN) or a high-fat (H) diet (NH) from weaning until adulthood. Offspring from obese H diet-fed parents were fed N (HN) or H diet (HH) after weaning. All offspring groups were submitted to bilateral AKI by clamping the left and right renal pedicles for 30 min. Compared with male NH and NN offspring from lean parents, male HH and HN offspring from obese parents exhibited higher kidney injury markers such as urinary, renal osteopontin, plasma creatinine, urinary albumin excretion, and neutrophil gelatinase-associated lipocalin (NGAL) levels, and worse histological injury score at 22 wk of age. Only albumin excretion and NGAL were elevated in female HH offspring from obese parents compared with lean and obese offspring from lean parents. We also found an increased mortality rate and worse kidney injury scores after AKI in male offspring from obese parents, regardless of the diet consumed after weaning. Female offspring were protected from major kidney injury after AKI. These results indicate that parental obesity leads to increased kidney injury in their offspring after ischemia-reperfusion in a sex-dependent manner, even when their offspring remain lean.NEW & NOTEWORTHY Offspring from obese parents are more susceptible to kidney injury and worse outcomes following an acute ischemia-reperfusion insult. Male, but not female, offspring from obese parents exhibit increased blood pressure early in life. Female offspring are partially protected against major kidney injury induced by ischemia-reperfusion.


Assuntos
Injúria Renal Aguda , Rim , Camundongos Endogâmicos C57BL , Traumatismo por Reperfusão , Animais , Masculino , Feminino , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/metabolismo , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/metabolismo , Injúria Renal Aguda/fisiopatologia , Injúria Renal Aguda/patologia , Rim/fisiopatologia , Rim/patologia , Rim/metabolismo , Fatores Sexuais , Obesidade/complicações , Obesidade/fisiopatologia , Dieta Hiperlipídica , Gravidez , Lipocalina-2/metabolismo , Obesidade Materna/metabolismo , Obesidade Materna/complicações , Obesidade Materna/fisiopatologia , Efeitos Tardios da Exposição Pré-Natal , Camundongos , Fatores de Risco , Modelos Animais de Doenças , Biomarcadores/sangue
12.
Am J Epidemiol ; 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38754872

RESUMO

Childhood adversity is an important risk factor for adverse health across the life course. Epigenetic modifications, such as DNA methylation (DNAm), are one hypothesized mechanism linking adversity to disease susceptibility. Yet, few studies have determined whether adversity-related DNAm alterations are causally related to future health outcomes or if their developmental timing plays a role in these relationships. Here, we used two-sample Mendelian Randomization to obtain stronger causal inferences about the association between adversity-associated DNAm loci across development (i.e., birth; childhood; adolescence; young adulthood) and 24 mental, physical, and behavioral health outcomes. We identified particularly strong associations between adversity-associated DNAm and ADHD, depression, obsessive-compulsive disorder, suicide attempts, asthma, coronary artery disease, and chronic kidney disease. A greater number of associations were identified for birth and childhood DNAm, while adolescent and young adulthood DNAm were more closely linked to mental health. Childhood DNAm loci also showed primarily risk suppressing relationships with health outcomes, suggesting that DNAm might reflect compensatory or buffering mechanisms against childhood adversity, rather than acting solely as an indicator of disease risk. Together, our results suggest adversity-related DNAm alterations are linked to both physical and mental health outcomes, with particularly strong impacts of DNAm differences emerging earlier in development.

13.
Anal Chem ; 96(40): 15960-15969, 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39334534

RESUMO

Specific lipid isomers are functionally critical, but their structural rigidity and usually minute geometry differences make separating them harder than other biomolecules. Such separations by ion mobility spectrometry (IMS) were recently enabled by new high-definition methods using dynamic electric fields, but major resolution gains are needed. Another problem of identifying many isomers with no unique fragments in ergodic collision-induced dissociation (CID) was partly addressed by the direct ozone-induced dissociation (OzID) that localizes the double bonds, but a low reaction efficiency has limited the sensitivity, dynamic range, throughput, and compatibility with other tools. Typically lipids are analyzed by MS as singly charged protonated, deprotonated, or ammoniated ions. Here, we explore the differential IMS (FAIMS) separations with OzID for exemplary lipids cationized by polyvalent metals. These multiply charged adducts have much greater FAIMS compensation voltages (UC) than the 1+ ions, with up to 10-fold resolution gain enabling baseline isomer separations even at a moderate resolving power of the SelexION stage. Concomitantly OzID speeds up by many orders of magnitude, producing a high yield of diagnostic fragments already in 1 ms. These capabilities can be ported to the superior high-definition FAIMS and high-pressure OzID systems to take lipidomic analyses to the next level.


Assuntos
Espectrometria de Mobilidade Iônica , Ozônio , Ozônio/química , Espectrometria de Mobilidade Iônica/métodos , Lipídeos/química , Isomerismo , Cátions/química , Metais/química , Polieletrólitos/química
14.
Anal Chem ; 96(14): 5392-5398, 2024 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-38526848

RESUMO

Along with mass spectrometry (MS), ion mobility separations (IMS) are advancing to ever larger biomolecules. The emergence of electrospray ionization (ESI) and native MS enabled the IMS/MS analyses of proteins up to ∼100 kDa in the 1990s and whole protein complexes and viruses up to ∼10 MDa since the 2000s. Differential IMS (FAIMS) is substantially orthogonal to linear IMS based on absolute mobility K and offers exceptional resolution, unique selectivity, and steady filtering readily compatible with slower analytical methods such as electron capture or transfer dissociation (ECD/ETD). However, the associated MS stages had limited FAIMS to ions with m/z < 8000 and masses under ∼300 kDa. Here, we integrate high-definition FAIMS with the Q-Exactive Orbitrap UHMR mass spectrometer that can handle m/z up to 80,000 and MDa-size ions in the native ESI regime. In the initial evaluation, the oligomers of monoclonal antibody adalimumab (148 kDa) are size-selected up to at least the nonamers (1.34 MDa) with m/z values up to ∼17,000. This demonstrates the survival and efficient separation of noncovalent MDa assemblies in the FAIMS process, opening the door to novel analyses of the heaviest macromolecules.


Assuntos
Espectrometria de Mobilidade Iônica , Proteínas , Espectrometria de Massas/métodos , Proteínas/química , Íons
15.
Anal Chem ; 96(6): 2318-2326, 2024 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-38301112

RESUMO

Ion mobility spectrometry (IMS) coupled to mass spectrometry (MS) has become a versatile tool to fractionate complex mixtures, distinguish structural isomers, and elucidate molecular geometries. Along with the whole MS field, IMS/MS advances to ever larger species. A topical proteomic problem is the discovery and characterization of d-amino acid-containing peptides (DAACPs) that are critical to neurotransmission and toxicology. Both linear IMS and FAIMS previously disentangled d/l epimers with up to ∼30 residues. In the first study using all three most powerful IMS methodologies─trapped IMS, cyclic IMS, and FAIMS─we demonstrate baseline resolution of the largest known d/l peptides (CHH from Homarus americanus with 72 residues) with a dynamic range up to 100. This expands FAIMS analyses of isomeric modified peptides, especially using hydrogen-rich buffers, to the ∼50-100 residue range of small proteins. The spectra for d and l are unprecedentedly strikingly similar except for a uniform shift of the separation parameter, indicating the conserved epimer-specific structural elements across multiple charge states and conformers. As the interepimer resolution tracks the average for smaller DAACPs, the IMS approaches could help search for yet larger DAACPs. The a priori method to calibrate cyclic (including multipass) IMS developed here may be broadly useful.


Assuntos
Peptídeos , Proteômica , Peptídeos/química , Espectrometria de Massas/métodos , Proteínas , Espectrometria de Mobilidade Iônica , Aminoácidos/química
16.
HIV Med ; 25(2): 188-200, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37776199

RESUMO

INTRODUCTION: The impact of specific policies on HIV care has been scarcely investigated. In this study we aimed to analyze the impact of the Treatment For All policy (TFA-2013) and the adoption of integrase strand transfer inhibitors (INSTIs-2017) as first-line therapy on clinical indicators of people living with HIV (PLHIV) in Brazil. METHODS: We assessed the public database of Brazil's Ministry of Health and extracted data from 2009 to 2019. We investigated the impact of TFA and INSTIs with a time-series analysis of four health indicators in PLHIV: antiretroviral treatment (ART) initiation with a CD4+ count >500/mm3 ; ART initiation <1 month after the first CD4+ measurement; viral load suppression (VLS); and treatment adherence. We explored trends over time by gender, age, macroregion of residency and municipal-level social vulnerability index. RESULTS: We included 753 316 PLHIV in 2019. Most were males (64.81%) in the 30-49 years age category (50.86%). We observed an overall improvement in all HIV clinical indicators, with notable impact of TFA on timely ART initiation and VLS, and mild impact of INSTIs on treatment adherence. Such improvements were heterogeneous, with remarkable gaps in gender, age and socioeconomic groups that have persisted over time. Indicators point to inferior outcomes among children, older adults, women and people living in socially vulnerable locations. CONCLUSIONS: Recent Brazilian public policies have had positive impacts on key HIV clinical indicators. However, our results highlight the need for specific policies to improve HIV care for children, older adults, women and socially vulnerable groups.


Assuntos
Síndrome da Imunodeficiência Adquirida , Fármacos Anti-HIV , Infecções por HIV , Masculino , Criança , Humanos , Feminino , Idoso , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Brasil/epidemiologia , Fatores Sociodemográficos , Antirretrovirais/uso terapêutico , Política Pública , Carga Viral , Política de Saúde , Fármacos Anti-HIV/uso terapêutico
17.
HIV Med ; 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39319744

RESUMO

INTRODUCTION: Mutations associated with HIV drug resistance (DR) affect clinical outcomes. Understanding the prevalence of HIV DR and its association with viral suppression and survival in the paediatric population is key to inform patient care and health policies. METHODS: We used Brazilian monitoring systems to identify genotyping tests performed in children living with HIV aged ≤18 months between 2009 and 2020. We categorized HIV DR using three criteria: any HIV DR (R1), DR to nevirapine or efavirenz (R2), and DR to at least one antiretroviral recommended for children with HIV in Brazilian guidelines (R3). We investigated factors associated with HIV DR, viral suppression, and survival up to 3 years old using multivariable models. Lastly, we describe the annual prevalence of each type of HIV DR in Brazilian children with HIV between 2009 and 2020. RESULTS: We included 1152 children with HIV with a median age of 5 months at genotype testing; 57% were females. R1 was observed in 30%, R2 in 17%, and R3 in 21%. Children with HIV whose birth parents were exposed to nevirapine or efavirenz before delivery had higher odds of R2 (odds ratio 3.4; 95% confidence interval [CI] 1.1-10.8). Children with HIV with R1 or R3 had higher rates of death than those with HIV with no HIV DR in the adjusted models (adjusted hazard ratios 4.7 [95% CI 1.6-13.9] and 4.1 [95% CI 1.4-12.4], respectively). The prevalence of resistance to nevirapine and efavirenz peaked in 2015. Over time, the prevalence of genotyping tests with no detected resistance varied between 57% and 87%. CONCLUSION: HIV DR is highly prevalent in children with HIV and is associated with lower survival.

18.
Methods ; 220: 142-157, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37939912

RESUMO

This review aims to provide a comprehensive overview of recent advancements and applications of fluorescence imaging probes synthesized via MCRs (multicomponent reactions). These probes, also known as functional chromophores, belong to a currently investigated class of fluorophores that are presently being successfully applied in bioimaging experiments, especially in various living cell lineages. We describe some of the MCRs that have been employed in the synthesis of these probes and explore their applications in biological imaging, with an emphasis on cellular imaging. The review also discusses the challenges and future perspectives in the field, particularly considering the potential impact of MCR-based fluorescence imaging probes on advancing this field of research in the coming years. Considering that this area of research is relatively new and nearly a decade has passed since the first publication, this review also provides a historical perspective on this class of fluorophores, highlighting the pioneering works published between 2011 and 2016.


Assuntos
Corantes Fluorescentes , Imagem Óptica
19.
An Acad Bras Cienc ; 96(3): e20230970, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38985033

RESUMO

The Irati Formation (Paraná Basin) is a mixed carbonate and organic-rich shale sequence intruded by Jurassic-Cretaceous basic rocks, featuring Brazil's most important oil shale deposits with different maturity levels. For the first time, the distribution of oil shale biomarkers from an outcrop section (quarry) of the Irati Formation in the northernmost Paraná Basin was analyzed by GC-MS and GC-MS/MS to determine the thermal evolution, organic matter origin and the depositional paleoenvironment. The organic-rich shale at the northernmost border of the basin has high similarity with the central and southernmost areas, indicating a primary control able to induce cyclic sedimentation in a broad (106 km2) and restricted environment. PCA and HCA analysis of bulk and molecular parameters showed changes in the organic matter composition and paleoenvironmental conditions throughout the stratigraphic column. Nonetheless, there are significant differences compared to the central-eastern and southern areas of the basin. Contrasting with the southern region, the north, predominates biphytane, low and medium gammacerane index. Pr/n-C17, Ph/n-C18, HI and OI values suggest type II/III kerogen from marine organic matter with freshwater input. Among the steranes, those of stereochemistry ααα 20R predominate over ααα 20S, and the presence of ßTm indicates the shales are less thermally evolved.


Assuntos
Biomarcadores , Sedimentos Geológicos , Brasil , Sedimentos Geológicos/química , Sedimentos Geológicos/análise , Biomarcadores/análise , Cromatografia Gasosa-Espectrometria de Massas , Lipídeos/análise , Fósseis
20.
An Acad Bras Cienc ; 96(1): e20230539, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38597500

RESUMO

Green manure (GM) may reduce the use of chemical fertilizers, been an ecologically appropriate strategy to cultivation of medicinal plants. Crotalaria juncea, is one of the most used because it adapts to different climatic and high nitrogen content. Origanum vulgare. is widely used in cooking, pharmaceutical, cosmetic industries and food products. The objectives of this study were to evaluate the GM on biomass, essential oil (EO), phenolic and antioxidant. The experiment consisted: control; 150, 300, 450, and 600 g (Sh= leaves+steam) more 200 g roots (R); 600 g aerial part; 200 g roots; and soil with 300 g cattle manure per pot. The highest dry weights were observed in the presence of GM and cattle manure (90 days). The control had an EO production 75% lower in relation to the dose of 450 g GM (Sh+R). Principal component analysis showed that GM and cattle manure positively influenced the dry weight, content, yield, and EO constituents, and total flavonoids. The GM contributed to the accumulation of the major EO compounds (trans-sabinene hydrate, thymol, terpinen-4-ol). The GM management may be beneficial for cultivating, because it can increase the production of biomass and the active components, in addition to being an inexpensive resource.


Assuntos
Crotalaria , Óleos Voláteis , Origanum , Bovinos , Animais , Óleos Voláteis/química , Origanum/química , Esterco , Biomassa , Compostos Fitoquímicos
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