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1.
Nat Commun ; 15(1): 3522, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38664386

RESUMO

Despite decades of research, the influence of climate on the export of dissolved organic carbon (DOC) from soil remains poorly constrained, adding uncertainty to global carbon models. The limited temporal range of contemporary monitoring data, ongoing climate reorganisation and confounding anthropogenic activities muddy the waters further. Here, we reconstruct DOC leaching over the last ~14,000 years using alpine environmental archives (two speleothems and one lake sediment core) across 4° of latitude from Te Waipounamu/South Island of Aotearoa New Zealand. We selected broadly comparable palaeoenvironmental archives in mountainous catchments, free of anthropogenically-induced landscape changes prior to ~1200 C.E. We show that warmer temperatures resulted in increased allochthonous DOC export through the Holocene, most notably during the Holocene Climatic Optimum (HCO), which was some 1.5-2.5 °C warmer than the late pre-industrial period-then decreased during the cooler mid-Holocene. We propose that temperature exerted the key control on the observed doubling to tripling of soil DOC export during the HCO, presumably via temperature-mediated changes in vegetative soil C inputs and microbial degradation rates. Future warming may accelerate DOC export from mountainous catchments, with implications for the global carbon cycle and water quality.

2.
Proc Natl Acad Sci U S A ; 121(11): e2307810121, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38437545

RESUMO

Treating pregnancy-related disorders is exceptionally challenging because the threat of maternal and/or fetal toxicity discourages the use of existing medications and hinders new drug development. One potential solution is the use of lipid nanoparticle (LNP) RNA therapies, given their proven efficacy, tolerability, and lack of fetal accumulation. Here, we describe LNPs for efficacious mRNA delivery to maternal organs in pregnant mice via several routes of administration. In the placenta, our lead LNP transfected trophoblasts, endothelial cells, and immune cells, with efficacy being structurally dependent on the ionizable lipid polyamine headgroup. Next, we show that LNP-induced maternal inflammatory responses affect mRNA expression in the maternal compartment and hinder neonatal development. Specifically, pro-inflammatory LNP structures and routes of administration curtailed efficacy in maternal lymphoid organs in an IL-1ß-dependent manner. Further, immunogenic LNPs provoked the infiltration of adaptive immune cells into the placenta and restricted pup growth after birth. Together, our results provide mechanism-based structural guidance on the design of potent LNPs for safe use during pregnancy.


Assuntos
Células Endoteliais , Feto , Lipossomos , Nanopartículas , Feminino , Gravidez , Humanos , Animais , Camundongos , RNA Mensageiro/genética , Cuidado Pré-Natal
3.
Water Res ; 211: 118054, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35066262

RESUMO

Large river systems, such as the River Ganges (Ganga), provide crucial water resources for the environment and society, yet often face significant challenges associated with cumulative impacts arising from upstream environmental and anthropogenic influences. Understanding the complex dynamics of such systems remains a major challenge, especially given accelerating environmental stressors including climate change and urbanization, and due to limitations in data and process understanding across scales. An integrated approach is required which robustly enables the hydrogeochemical dynamics and underpinning processes impacting water quality in large river systems to be explored. Here we develop a systematic approach for improving the understanding of hydrogeochemical dynamics and processes in large river systems, and apply this to a longitudinal survey (> 2500 km) of the River Ganges (Ganga) and key tributaries in the Indo-Gangetic basin. This framework enables us to succinctly interpret downstream water quality trends in response to the underpinning processes controlling major element hydrogeochemistry across the basin, based on conceptual water source signatures and dynamics. Informed by a 2019 post-monsoonal survey of 81 river bank-side sampling locations, the spatial distribution of a suite of selected physico-chemical and inorganic parameters, combined with segmented linear regression, reveals minor and major downstream hydrogeochemical transitions. We use this information to identify five major hydrogeochemical zones, characterized, in part, by the inputs of key tributaries, urban and agricultural areas, and estuarine inputs near the Bay of Bengal. Dominant trends are further explored by investigating geochemical relationships (e.g. Na:Cl, Ca:Na, Mg:Na, Sr:Ca and NO3:Cl), and how water source signatures and dynamics are modified by key processes, to assess the relative importance of controls such as dilution, evaporation, water-rock interactions (including carbonate and silicate weathering) and anthropogenic inputs. Mixing/dilution between sources and water-rock interactions explain most regional trends in major ion chemistry, although localized controls plausibly linked to anthropogenic activities are also evident in some locations. Temporal and spatial representativeness of river bank-side sampling are considered by supplementary sampling across the river at selected locations and via comparison to historical records. Limitations of such large-scale longitudinal sampling programs are discussed, as well as approaches to address some of these inherent challenges. This approach brings new, systematic insight into the basin-wide controls on the dominant geochemistry of the River Ganga, and provides a framework for characterising dominant hydrogeochemical zones, processes and controls, with utility to be transferable to other large river systems.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , Monitoramento Ambiental , Índia , Rios , Poluentes Químicos da Água/análise , Qualidade da Água , Tempo (Meteorologia)
4.
Microorganisms ; 9(8)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34442702

RESUMO

This work investigates the origin and range of fluorescent organic matter (FOM) produced in-situ by environmentally sourced freshwater bacteria. Aquatic FOM is an essential component in global carbon cycling and is generally classified as either autochthonous, produced in-situ via microbial processes, or allochthonous, transported into aquatic systems from external sources. We have demonstrated that, within laboratory model systems, environmentally sourced mixed microbial communities and bacterial isolates can produce and/or export FOM associated with both autochthonous and allochthonous material. This study focuses on fluorescence peak B, T, M, C and C+, exploring (1) the cellular nature of FOM produced, (2) FOM exported as extracellular material into the water column and (3) the impact of physical cell lysis on FOM signature. For the laboratory model systems studied, Peak T fluorescence is retained within bacterial cells (>68%), while Peak C fluorescence is mainly observed as extracellular material (>80%). Peak M is identified as both cellular and extracellular FOM, produced by all isolated freshwater microorganisms investigated. The origin of Peak C+ is postulated to originate from functional metabolites associated with specific microorganisms, seen specifically within the Pseudomonas sp. monoculture here. This work challenges the binary classification of FOM as either allochthonous or autochthonous, suggesting that FOM processing and production occurs along a dynamic continuum. Within this study, fluorescence intensity data for the environmental bacteria isolate monocultures are presented as enumeration corrected data, for the first time providing quantitative fluorescence data per bacterial colony forming unit (cfu). From this, we are able to assess the relative contribution of different bacteria to the autochthonous FOM pool and if this material is cellular or extracellular.

5.
Sci Total Environ ; 738: 139419, 2020 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-32521357

RESUMO

We explore in-situ fluorescence spectroscopy as an instantaneous indicator of total bacterial abundance and faecal contamination in drinking water. Eighty-four samples were collected outside of the recharge season from groundwater-derived water sources in Dakar, Senegal. Samples were analysed for tryptophan-like (TLF) and humic-like (HLF) fluorescence in-situ, total bacterial cells by flow cytometry, and potential indicators of faecal contamination such as thermotolerant coliforms (TTCs), nitrate, and in a subset of 22 samples, dissolved organic carbon (DOC). Significant single-predictor linear regression models demonstrated that total bacterial cells were the most effective predictor of TLF, followed by on-site sanitation density; TTCs were not a significant predictor. An optimum multiple-predictor model of TLF incorporated total bacterial cells, nitrate, nitrite, on-site sanitation density, and sulphate (r2 0.68). HLF was similarly related to the same parameters as TLF, with total bacterial cells being the best correlated (ρs 0.64). In the subset of 22 sources, DOC clustered with TLF, HLF, and total bacterial cells, and a linear regression model demonstrated HLF was the best predictor of DOC (r2 0.84). The intergranular nature of the aquifer, timing of the study, and/or non-uniqueness of the signal to TTCs can explain the significant associations between TLF/HLF and indicators of faecal contamination such as on-site sanitation density and nutrients but not TTCs. The bacterial population that relates to TLF/HLF is likely to be a subsurface community that develops in-situ based on the availability of organic matter originating from faecal sources. In-situ fluorescence spectroscopy instantly indicates a drinking water source is impacted by faecal contamination but it remains unclear how that relates specifically to microbial risk in this setting.


Assuntos
Carbono , Microbiologia da Água , Monitoramento Ambiental , Fluorescência , Senegal , Espectrometria de Fluorescência
6.
J Child Adolesc Psychopharmacol ; 24(8): 419-25, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25299355

RESUMO

UNLABELLED: Abstract Objective: This study assessed the efficacy of atomoxetine on attention-deficit/hyperactivity disorder (ADHD) symptoms in children and adolescents having ADHD with comorbid dyslexia (ADHD+D) and the effects of the treatment on reading measures. METHODS: The analyses in this report used data from a study designed to examine the effects of a nonstimulant pharmacological agent, atomoxetine, on reading in children with ADHD+D. Patients ages 10-16 years with ADHD or ADHD+D received open-label atomoxetine for 16 weeks. The ADHD Rating Scale (ADHD-RS) and reading subtests of the Kaufman Test of Educational Achievement (K-TEA) were assessed. Changes in ADHD symptoms and reading scores were also analyzed by ADHD subtype. Treatment effect sizes and correlations between changes in ADHDRS and K-TEA scores were calculated. RESULTS: After atomoxetine treatment, both ADHD and ADHD+D patient groups showed significant reduction in ADHD symptom and improvements in K-TEA reading scores. The range of treatment effect sizes on K-TEA scores was 0.35-0.53 for the ADHD group and 0.50-0.62 for the ADHD+D group. Pearson's correlation coefficients revealed only a few weak correlations between changes in ADHD symptoms and reading scores, regardless of diagnostic group. CONCLUSIONS: ADHD symptoms and K-TEA reading scores improved for both the ADHD and ADHD+D groups following atomoxetine treatment. Correlation analyses indicate that improvements in reading outcomes cannot be explained by a reduction of ADHD symptoms alone. These findings support further exploration of the potential effects of atomoxetine on reading in children with ADHD and dyslexia or dyslexia alone.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Estimulantes do Sistema Nervoso Central/uso terapêutico , Dislexia/tratamento farmacológico , Propilaminas/uso terapêutico , Leitura , Adolescente , Cloridrato de Atomoxetina , Criança , Feminino , Humanos , Masculino , Resultado do Tratamento
7.
J Clin Psychopharmacol ; 33(1): 45-54, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23277268

RESUMO

BACKGROUND: Attention-deficit/hyperactivity disorder (ADHD) is associated with significant impairment in multiple functional domains. This trial evaluated efficacy in ADHD symptoms and functional outcomes in young adults treated with atomoxetine. METHODS: Young adults (18-30 years old) with ADHD were randomized to 12 weeks of double-blind treatment with atomoxetine (n = 220) or placebo (n = 225). The primary efficacy measure of ADHD symptom change was Conners' Adult ADHD Rating Scale (CAARS): Investigator-Rated: Screening Version Total ADHD Symptoms score with adult prompts. Secondary outcomes scales included the Adult ADHD Quality of Life-29, Clinical Global Impression-ADHD-Severity, Patient Global Impression-Improvement, CAARS Self-Report, Behavior Rating Inventory of Executive Function-Adult Version Self-Report, and assessments of depression, anxiety, sleepiness, driving behaviors, social adaptation, and substance use. RESULTS: Atomoxetine was superior to placebo on CAARS: Investigator-Rated: Screening Version (atomoxetine [least-squares mean ± SE, -13.6 ± 0.8] vs placebo [-9.3 ± 0.8], 95% confidence interval [-6.35 to -2.37], P < 0.001), Clinical Global Impression-ADHD-Severity (atomoxetine [-1.1 ± 0.1] vs placebo [-0.7 ± 0.1], 95% confidence interval [-0.63 to -0.24], P < 0.001), and CAARS Self-Report (atomoxetine [-11.9 ± 0.8] vs placebo [-7.8 ± 0.7], 95% confidence interval [-5.94 to -2.15], P < 0.001) but not on Patient Global Impression-Improvement. In addition, atomoxetine was superior to placebo on Adult ADHD Quality of Life-29 and Behavior Rating Inventory of Executive Function-Adult Version Self-Report. Additional assessments failed to detect significant differences (P ≥ 0.05) between atomoxetine and placebo. The adverse event profile was similar to that observed in other atomoxetine studies. Nausea, decreased appetite, insomnia, dry mouth, irritability, dizziness, and dyspepsia were reported significantly more often with atomoxetine than with placebo. CONCLUSIONS: Atomoxetine reduced ADHD symptoms and improved quality of life and executive functioning deficits in young adults compared with placebo. Atomoxetine was also generally well tolerated.


Assuntos
Inibidores da Captação Adrenérgica/uso terapêutico , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Propilaminas/uso terapêutico , Adolescente , Inibidores da Captação Adrenérgica/efeitos adversos , Adulto , Análise de Variância , Cloridrato de Atomoxetina , Atenção/efeitos dos fármacos , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Método Duplo-Cego , Função Executiva/efeitos dos fármacos , Humanos , Análise dos Mínimos Quadrados , Valor Preditivo dos Testes , Propilaminas/efeitos adversos , Estudos Prospectivos , Escalas de Graduação Psiquiátrica , Porto Rico , Qualidade de Vida , Recuperação de Função Fisiológica , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento , Estados Unidos , Adulto Jovem
8.
Food Drug Law J ; 67(1): 83-101, iii, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-24624650

RESUMO

While FDA gathers vast amounts of data about prescription drugs prior to their marketing approval, important information about the relative effectiveness and long term safety of products is not required for approval, and often is never collected. Increased postmarket research on the safety and comparative effectiveness of products would improve medical decisionmaking and lead to better clinical outcomes. Fortunately, Congress has recognized the value of this information for healthcare professionals. In response to a congressional mandate in the FDA Amendments Act (FDAAA), FDA is developing the Sentinel Initiative, an active surveillance system for monitoring postmarket drug safety issues. FDAAA also authorized FDA to require a drug sponsor to conduct postmarket safety studies or clinical trials to address a specific safety concern. To increase the repository of comparative effectiveness information, Congress established the Patient-Centered Outcomes Research Institute (PCORI) in the Patient Protection and Affordable Care Act (PPACA), directing it to manage comparative effectiveness research (CER). This article discusses the need for better safety and comparative effectiveness information and outlines methods to efficiently conduct the research and communicate it effectively to healthcare professionals. Coordination between FDA and the PCORI in gathering and communicating postmarket information is recommended. Medical source data collected by the Sentinel Initiative should be used for CER in addition to postmarket safety surveillance, and FDA and the PCORI should adopt identical standards for the distribution and communication of CER. Coordination between the two entities is recommended to save costs, reduce duplication of efforts, and to generate and communicate more information on prescription drugs for medical decisionmakers.


Assuntos
Pesquisa Comparativa da Efetividade , Tomada de Decisões , Vigilância de Produtos Comercializados , Humanos , Estados Unidos
9.
Mol Biol Cell ; 19(1): 207-15, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17978090

RESUMO

The gamma-tubulin small complex (gamma-TuSC) is an evolutionarily conserved heterotetramer essential for microtubule nucleation. We have determined the structure of the Saccharomyces cerevisiae gamma-TuSC at 25-A resolution by electron microscopy. gamma-TuSC is Y-shaped, with an elongated body connected to two arms. Gold labeling showed that the two gamma-tubulins are located in lobes at the ends of the arms, and the relative orientations of the other gamma-TuSC components were determined by in vivo FRET. The structures of different subpopulations of gamma-TuSC indicate flexibility in the connection between a mobile arm and the rest of the complex, resulting in variation of the relative positions and orientations of the gamma-tubulins. In all of the structures, the gamma-tubulins are distinctly separated, a configuration incompatible with the microtubule lattice. The separation of the gamma-tubulins in isolated gamma-TuSC likely plays a role in suppressing its intrinsic microtubule-nucleating activity, which is relatively weak until the gamma-TuSC is incorporated into higher order complexes or localized to microtubule-organizing centers. We propose that further movement of the mobile arm is required to bring the gamma-tubulins together in microtubule-like interactions, and provide a template for microtubule growth.


Assuntos
Microtúbulos/química , Proteínas de Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/química , Tubulina (Proteína)/química , Transferência Ressonante de Energia de Fluorescência , Microscopia Eletrônica , Modelos Moleculares , Nucleotídeos/metabolismo , Maleabilidade , Saccharomyces cerevisiae/ultraestrutura , Proteínas de Saccharomyces cerevisiae/ultraestrutura , Tubulina (Proteína)/ultraestrutura
10.
Dev Biol ; 300(2): 570-82, 2006 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-17055473

RESUMO

Division abnormally delayed (Dally) is one of two glycosylphosphatidylinositol (GPI)-linked heparan sulfate proteoglycans in Drosophila. Numerous studies have shown that it influences Decapentaplegic (Dpp) and Wingless signaling. It has been generally assumed that Dally affects signaling by directly interacting with these growth factors, primarily through its heparan sulfate (HS) chains. To understand the functional contributions of HS chains and protein core we have (1) assessed the growth factor binding properties of purified Dally using surface plasmon resonance, (2) generated a form of Dally that is not HS modified and evaluated its signaling capacity in vivo. Purified Dally binds directly to FGF2, FGF10, and the functional Dpp homolog BMP4. FGF binding is abolished by preincubation with HS, but BMP4 association is partially HS-resistant, suggesting the Dally protein core contributes to binding. Cell binding and co-immunoprecipitation studies suggest that non-HS-modified Dally retains some ability to bind Dpp or BMP4. Expression of HS-deficient Dally in vivo showed it does not promote signaling as well as wild-type Dally, yet it can rescue several dally mutant phenotypes. These data reveal that heparan sulfate modification of Dally is not required for all in vivo activities and that significant functional capacity resides in the protein core.


Assuntos
Proteínas de Drosophila/fisiologia , Glipicanas/fisiologia , Heparitina Sulfato/metabolismo , Glicoproteínas de Membrana/fisiologia , Proteoglicanas/fisiologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular , Proteínas de Drosophila/química , Proteínas de Drosophila/genética , Glipicanas/química , Glipicanas/genética , Heparitina Sulfato/química , Glicoproteínas de Membrana/química , Glicoproteínas de Membrana/genética , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Proteoglicanas/química , Proteoglicanas/genética , Relação Estrutura-Atividade
11.
Mol Cell ; 12(6): 1353-65, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14690591

RESUMO

Interpreting genome sequences requires the functional analysis of thousands of predicted proteins, many of which are uncharacterized and without obvious homologs. To assess whether the roles of large sets of uncharacterized genes can be assigned by targeted application of a suite of technologies, we used four complementary protein-based methods to analyze a set of 100 uncharacterized but essential open reading frames (ORFs) of the yeast Saccharomyces cerevisiae. These proteins were subjected to affinity purification and mass spectrometry analysis to identify copurifying proteins, two-hybrid analysis to identify interacting proteins, fluorescence microscopy to localize the proteins, and structure prediction methodology to predict structural domains or identify remote homologies. Integration of the data assigned function to 48 ORFs using at least two of the Gene Ontology (GO) categories of biological process, molecular function, and cellular component; 77 ORFs were annotated by at least one method. This combination of technologies, coupled with annotation using GO, is a powerful approach to classifying genes.


Assuntos
Biologia Computacional , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Genoma Fúngico , Análise de Sequência com Séries de Oligonucleotídeos , Fases de Leitura Aberta , Proteoma/análise , Técnicas do Sistema de Duplo-Híbrido
12.
J Cell Sci ; 115(Pt 1): 123-30, 2002 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-11801730

RESUMO

division abnormally delayed (dally) encodes an integral membrane proteoglycan of the glypican family that affects a number of patterning events during both embryonic and larval development. Earlier studies demonstrated that Dally regulates cellular responses to Wingless (Wg) and Decapentaplegic (Dpp) in a tissue-specific manner, consistent with its proposed role as a growth factor co-receptor. dally mutants also display cell cycle progression defects in specific sets of dividing cells in the developing optic lobe and retina. The affected cells in the retina and lamina show delays in completion of the G2-M segment of the cell cycle. We have investigated the molecular basis of dally-mediated cell division defects by examining the genetic interactions between dally and known cell cycle regulators. Reductions in cyclin A but not cyclin B or string expression, suppress dally cell division defects in the optic lobe. cycA mutations also dominantly rescue many dally adult morphological defects including lethality, phenotypes that are unaffected by reducing cycB function. dally mutants show abnormal Cyclin A expression in the dividing cells affected, with appreciable levels of Cyclin A remaining in late prophase and metaphase, stages where Cyclin A is normally absent. Given that Dally is known to regulate the activity of secreted growth factors our findings suggest that extracellular cues influence the degradation of Cyclin A in a manner that controls cell cycle progression and ultimately, cell division patterning.


Assuntos
Ciclo Celular/fisiologia , Ciclina A/metabolismo , Drosophila/embriologia , Glicoproteínas de Membrana/fisiologia , Proteoglicanas/fisiologia , Alelos , Animais , Ciclo Celular/genética , Divisão Celular/genética , Divisão Celular/fisiologia , Cruzamentos Genéticos , Ciclina A/genética , Drosophila/genética , Drosophila/ultraestrutura , Proteínas de Drosophila , Olho/citologia , Olho/embriologia , Olho/ultraestrutura , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Genes de Insetos , Masculino , Glicoproteínas de Membrana/genética , Microscopia Eletrônica de Varredura , Morfogênese , Mutação , Lobo Óptico de Animais não Mamíferos/citologia , Lobo Óptico de Animais não Mamíferos/embriologia , Lobo Óptico de Animais não Mamíferos/ultraestrutura , Fenótipo , Proteoglicanas/genética
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