Latin America's Nitrogen Challenge Austin, A. T.; Bustamante, M. M. C.; Nardoto, G. B. ...
Science (American Association for the Advancement of Science),
04/2013, Letnik:
340, Številka:
6129
Journal Article
Recenzirano
Odprti dostop
Latin America (LA) has many social indicators similar to those of highly developed economies but most frequently falls midway between least developed countries and industrialized regions. To move ...forward, LA must address uncontrolled urbanization, agricultural production, social inequity, and destruction of natural resources. We discuss these interrelated challenges in terms of human impact on the nitrogen (N) cycle. Human activity has caused unprecedented changes to the global N cycle; in the past century; total global fixation of reactive N (Nr) has at least doubled (1). Excess Nr leaked into the environment negatively affects soils, atmosphere, and water resources in temperate zones (1). In addition to N excess from human impact, mining of natural soil N creates N deficits in some regions (2, 3).
We previously associated HIST1H1E mutations causing Rahman syndrome with a specific genome-wide methylation pattern.
Methylome analysis from peripheral blood samples of six affected subjects led us ...to identify a specific hypomethylated profile. This "episignature" was enriched for genes involved in neuronal system development and function. A computational classifier yielded full sensitivity and specificity in detecting subjects with Rahman syndrome. Applying this model to a cohort of undiagnosed probands allowed us to reach diagnosis in one subject.
We demonstrate an epigenetic signature in subjects with Rahman syndrome that can be used to reach molecular diagnosis.
This study documents regional patterns in stream nitrogen and phosphorus concentrations in the Brazilian state of Rondônia in the southwestern Amazon basin, and interprets the patterns as functions ...of watershed soil properties, deforestation extent, and urban population density. The survey includes 77 different locations sampled in the dry and wet seasons, with a watershed size range from 1.8 to 33,000 km2 over a total area of approximately 140,000 km2. A sequential regression technique is used to separate the effects of natural watersheds properties and anthropogenic disturbance on nutrients and chloride. Natural variation in soil texture explains most of the variance in stream nitrate concentrations, while deforestation extent and urban population density explain most of the variance in stream chloride (Cl) and total dissolved nitrogen (TDN) concentrations. Stream TDN, total dissolved phosphorus (TDP), particulate phosphorus (PP) and Cl concentrations all increase non-linearly with deforestation extent in the dry season after controlling for natural variability due to soil type. Stream nutrient and Cl disturbances are observed only in watersheds more than 66-75% deforested (watershed area range 2-300 km2), suggesting stream nutrient concentrations are resistant to perturbation from vegetation conversion below a 66-75% threshold. In heavily deforested watersheds, stream Cl shows the largest changes in concentration (12 ± 6 times forested background), followed by TDP (2.3 ± 1.5), PP (1.9 ± 0.8) and TDN (1.7 ± 0.5). Wet season signals in Cl and TDP are diluted relative to the dry season, and no land use signal is observed in wet season TDN, PN, or PP. Stream TDN and TDP concentrations in non-urban watersheds both correlate with stream Cl, suggesting that sources other than vegetation and soil organic matter contribute to enhanced nutrient concentrations. Small, urbanized watersheds (5-20 km2) have up to 40 times the chloride and 10 times the TDN concentrations of forested catchments in the dry season. Several large watersheds (∼ 1000-3000 km2) with urban populations show higher Cl, TDN and TDP levels than any small pasture watershed, suggesting that human impacts on nutrient concentrations in large river systems may be dominated by urban areas. Anthropogenic disturbance of dry-season stream Cl and TDN is detectable in large streams draining deforested and urbanized watersheds up to 33,000 km2. We conclude that regional deforestation and urbanization result in changes in stream Cl, N and P concentrations at wide range of scales, from small pasture streams to large river systems.
Lignin phenols were measured in the sediments of Sepitiba Bay, Rio de Janeiro, Brazil and in bedload sediments and suspended sediments of the four major fluvial inputs to the bay; São Francisco and ...Guandu Channels and the Guarda and Cação Rivers. Fluvial suspended lignin yields (Σ8 3.5–14.6
mgC
10
g
dw
−1) vary little between the wet and dry seasons and are poorly correlated with fluvial chlorophyll concentrations (0.8–50.2
μgC
L
−1). Despite current land use practices that favor grassland agriculture or industrial uses, fluvial lignin compositions are dominated by a degraded leaf-sourced material. The exception is the Guarda River, which has a slight influence from grasses. The Lignin Phenol Vegetation Index, coupled with acid/aldehyde and 3.5
Db/V ratios, indicate that degraded leaf-derived phenols are also the primary preserved lignin component in the bay. The presence of fringe
Typha sp. and
Spartina sp. grass beds surrounding portions of the Bay are not reflected in the lignin signature. Instead, lignin entering the bay appears to reflect the erosion of soils containing a degraded signature from the former Atlantic rain forest that once dominated the watershed, instead of containing a significant signature derived from current agricultural uses. A three-component mixing model using the LPVI, atomic N:C ratios, and stable carbon isotopes (which range between –26.8 and –21.8‰) supports the hypothesis that fluvial inputs to the bay are dominated by planktonic matter (78% of the input), with lignin dominated by leaf (14% of the input) over grass (6%). Sediments are composed of a roughly 50–50 mixture of autochthonous material and terrigenous material, with lignin being primarily sourced from leaf.
Alzheimer's disease (AD) is a progressive and incurable neurodegenerative disorder of integrative areas of the brain, characterized by cognitive decline and disability resulting in negative impacts ...on the family of the patients and the health care services worldwide. AD involves oxidative stress, neuroinflammation and accelerated apoptosis, accompanied by deposition of amyloid-β peptide plaques and tau protein-based neurofibrillary tangles in the central nervous system. Among the multiple factors that contribute to the onset and evolution of this disease, aging stands out. That is why the prevalence of this disease has increased due to the constant increase in life expectancy. In the hope of finding new, more effective methods to slow the progression of this disease, over the last two decades, researchers have promoted “omics”-based approaches that include the gut microbiota and their reciprocal interactions with different targets in the body. This scientific advance has also led to a better understanding of brain compartments and the mechanisms that affect the integrity of the blood-brain barrier. This review aims to discuss recent advances related to the gut-brain-microbiota axis in AD. Furthermore, considering that AD involves psychiatric symptoms, this review also focuses on the psychiatric factors that interact with this axis (an issue that has not yet been sufficiently addressed in the literature).
Background/Objectives: Vitamin A deficiency (VAD) is a major public health problem. The supplementation of lactating women could be an effective strategy to combat it. The objective of this study was ...to assess the impact of maternal vitamin A supplementation on the mother–infant pair. Subjects/Methods: This was a double blind, placebo-controlled randomized clinical assay in which 33 women received 200 000 IU of vitamin A and 33 women received soy oil between 20th and 30th postpartum days. Maternal blood and milk samples were collected immediately before supplementation and 3 months after delivery, when blood was also collected from the babies. Retinol concentrations 0.70 μmol/l in serum and 1.05 μmol/l in milk were considered to indicate VAD. Results: Increase in serum retinol level was observed in the supplemented group compared with the pre-supplementation levels (1.05 and 1.17 μmol/l, respectively; P=0.026) and to the post-supplementation levels of the control group (1.02 μmol/l; P=0.032). Reduction in breast milk retinol was observed in the control group compared with the pre-supplementation levels (1.93 and 1.34 μmol/l, respectively; P<0.0001) and to the post-supplementation levels of the supplemented group (1.56 μmol/l; P=0.0003). There was significant difference in the prevalence of VAD in breast milk after supplementation, 55.6% (15/27) in the control group and 16.1% (5/31) in the supplemented group (P=0.002). VAD was present in 66.1% (39/59) of infants, with mean serum retinol levels of 0.64±0.30 μmol/l in the control group and of 0.69±0.26 μmol/l in the supplemented group. Conclusions: Supplementation had a positive impact on maternal vitamin A status. No effect on infant status was detectable 2 months after supplementation with a single dose.
Essentials
Deep vein thrombosis (DVT) has a large unknown genetic component.
We sequenced coding areas of 734 hemostasis‐related genes in 899 DVT patients and 599 controls.
Variants in F5, FGA‐FGG, ...CYP4V2‐KLKB1‐F11, and ABO were associated with DVT risk.
Associations in
KLKB1 and F5 suggest a more complex genetic architecture than previously thought.
Summary
Background
Although several genetic risk factors for deep vein thrombosis (DVT) are known, almost all related to hemostasis, a large genetic component remains unexplained.
Objectives
To identify novel genetic determinants by using targeted DNA sequencing.
Patients/Methods
We included 899 DVT patients and 599 controls from three case–control studies (DVT‐Milan, Multiple Environmental and Genetic Assessment of risk factors for venous thrombosis MEGA, and the Thrombophilia, Hypercoagulability and Environmental Risks in Venous Thromboembolism THE‐VTE study) for sequencing of the coding regions of 734 genes involved in hemostasis or related pathways. We performed single‐variant association tests for common variants (minor allele frequency MAF ≥ 1%) and gene‐based tests for rare variants (MAF ≤ 1%), accounting for multiple testing by use of the false discovery rate (FDR).
Results
Sixty‐two of 3617 common variants were associated with DVT risk (FDR < 0.10). Most of these mapped to F5,ABO,FGA–FGG, and CYP4V2–KLKB1–F11. The lead variant at F5 was rs6672595 (odds ratio OR 1.58, 95% confidence interval CI 1.29–1.92), in moderate linkage with the known variant rs4524. Reciprocal conditional analyses suggested that intronic variation might drive this association. We also observed a secondary association at the F11 region: missense KLKB1 variant rs3733402 remained associated conditional on known variants rs2039614 and rs2289252 (OR 1.36, 95% CI 1.10–1.69). Two novel variant associations were observed, in CBS and MASP1, but these were not replicated in the meta‐analysis data from the International Network against Thrombosis (INVENT) consortium. There was no support for a burden of rare variants contributing to DVT risk (FDR > 0.2).
Conclusions
We confirmed associations between DVT and common variants in F5,ABO,FGA–FGG, and CYP4V2–KLKB1–F11, and observed secondary signals in F5 and CYP4V2–KLKB1–F11 that warrant replication and fine‐mapping in larger studies.
To assess pregnancy and fetal outcomes after in utero exposure to interferon-β (IFNβ) in all pregnancies occurring in women with multiple sclerosis (MS) during the study period, with a specific focus ...on the risk of spontaneous abortion.
In this cohort study, data were gathered through a standardized, semi-structured interview. Patients who discontinued IFNβ less than 4 weeks from conception (exposed) were compared with those who had discontinued the drug at least 4 weeks from conception or who were never treated (not exposed). Possible confounders were handled through multivariate analyses adjusted for propensity score (PS).
We collected data on 396 pregnancies in 388 women, 88 classified as exposed (mean exposure 4.6 ± 5.8 weeks). IFNβ exposure was not associated with an increased risk of spontaneous abortion (PS-adjusted odds ratio OR 1.08, 95% confidence interval CI 0.4 to 2.9, p = 0.88), although it was associated with both lower baby weight (PS-adjusted β -113.8, p < 0.0001) and length (PS-adjusted β -1.102, p < 0.0001). Proportion of spontaneous abortion in exposed patients fell within the range expected for the Italian population in the same period. IFNβ exposure (PS-adjusted OR 2.11, 95% CI 1.18 to 3.78, p = 0.012) and cesarean delivery were the only predictors of preterm delivery. In the exposed group, we did not observe any significant fetal complications, malformations, or developmental abnormalities over a median follow-up of 2.1 years.
Our findings point to the relative safety of IFNβ exposure times of up to 4 weeks and can assist neurologists facing therapeutic decisions in women with MS with a pregnancy plan.
Interactions between distant places are increasingly widespread and influential, often leading to unexpected outcomes with profound implications for sustainability. Numerous sustainability studies ...have been conducted within a particular place with little attention to the impacts of distant interactions on sustainability in multiple places. Although distant forces have been studied, they are usually treated as exogenous variables and feedbacks have rarely been considered. To understand and integrate various distant interactions better, we propose an integrated framework based on telecoupling, an umbrella concept that refers to socioeconomic and environmental interactions over distances. The concept of telecoupling is a logical extension of research on coupled human and natural systems, in which interactions occur within particular geographic locations. The telecoupling framework contains five major interrelated components, i.e., coupled human and natural systems, flows, agents, causes, and effects. We illustrate the framework using two examples of distant interactions associated with trade of agricultural commodities and invasive species, highlight the implications of the framework, and discuss research needs and approaches to move research on telecouplings forward. The framework can help to analyze system components and their interrelationships, identify research gaps, detect hidden costs and untapped benefits, provide a useful means to incorporate feedbacks as well as trade-offs and synergies across multiple systems (sending, receiving, and spillover systems), and improve the understanding of distant interactions and the effectiveness of policies for socioeconomic and environmental sustainability from local to global levels.
A comprehensive new inventory of Brazilian plants and fungi was published just in time to meet a 2010 Convention on Biological Diversity target and offers important insights into this biodiversity's ...global significance. Brazil is the home to the world's richest flora (40,989 species; 18,932 endemic) and includes two of the hottest hotspots: Mata Atlântica (19,355 species) and Cerrado (12,669 species). Although the total number of known species is one-third lower than previous estimates, the absolute number of endemic vascular plant species is higher than was previously estimated, and the proportion of endemism (56%) is the highest in the Neotropics. This compilation serves not merely to quantify the scale of the challenge faced in conserving Brazil's unique flora but also serves as a key resource to direct action and monitor progress. Similar efforts by other megadiverse countries are urgently required if the 2020 targets of the Convention on Biological Diversity and the Global Strategy for Plant Conservation are to be attained.
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