-
International Journal of Molecular... Mar 2024Research on carbon-based nanomaterials, such as carbon nanotubes and graphene and its derivatives, has experienced exponential development in recent years [...].
Research on carbon-based nanomaterials, such as carbon nanotubes and graphene and its derivatives, has experienced exponential development in recent years [...].
Topics: Nanotubes, Carbon; Nanostructures; Graphite
PubMed: 38474275
DOI: 10.3390/ijms25053032 -
The Journal of Emergency Medicine Aug 2023The use of sodium bicarbonate to treat metabolic acidosis is intuitive, yet data suggest that not all patients benefit from this therapy. (Review)
Review
BACKGROUND
The use of sodium bicarbonate to treat metabolic acidosis is intuitive, yet data suggest that not all patients benefit from this therapy.
OBJECTIVE
In this narrative review, we describe the physiology behind commonly encountered nontoxicologic causes of metabolic acidosis, highlight potential harm from the indiscriminate administration of sodium bicarbonate in certain scenarios, and provide evidence-based recommendations to assist emergency physicians in the rational use of sodium bicarbonate.
DISCUSSION
Sodium bicarbonate can be administered as a hypertonic push, as a resuscitation fluid, or as an infusion. Lactic acidosis and cardiac arrest are two common scenarios where there is limited benefit to routine use of sodium bicarbonate, although certain circumstances, such as patients with concomitant acute kidney injury and lactic acidosis may benefit from sodium bicarbonate. Patients with cardiac arrest secondary to sodium channel blockade or hyperkalemia also benefit from sodium bicarbonate therapy. Recent data suggest that the use of sodium bicarbonate in diabetic ketoacidosis does not confer improved patient outcomes and may cause harm in pediatric patients. Available evidence suggests that alkalinization of urine in rhabdomyolysis does not improve patient-centered outcomes. Finally, patients with a nongap acidosis benefit from sodium bicarbonate supplementation.
CONCLUSIONS
Empiric use of sodium bicarbonate in patients with nontoxicologic causes of metabolic acidosis is not warranted and likely does not improve patient-centered outcomes, except in select scenarios. Emergency physicians should reserve use of this medication to conditions with clear benefit to patients.
Topics: Humans; Child; Bicarbonates; Sodium Bicarbonate; Acidosis, Lactic; Acidosis; Heart Arrest
PubMed: 37442665
DOI: 10.1016/j.jemermed.2023.04.012 -
Proceedings of the National Academy of... Oct 2023Previous evaluations on the biophysical potential of forest carbon sink have focused on forestation area distribution and the associated carbon stock for...
Previous evaluations on the biophysical potential of forest carbon sink have focused on forestation area distribution and the associated carbon stock for equilibrium-state forests after centuries-long growth. These approaches, however, have limited relevance for climate policies because they ignore the near-term and mid-term decadal carbon uptake dynamics and suitable forest species for forestation. This study developed a forestation roadmap to support China's "carbon neutrality" objective in 2060 by addressing three key questions of forestation: where, with what forest species, and when to afforest. The results yielded a high-confidence potential forestation map for China at a resolution of 1 km with the identified optimal native forest type or species. Our analysis revealed an additional 78 Mha suitable for forestation up to the 2060s, a 43% increase on the current forest area. Selecting forest species for maximal carbon stock in addition to maximizing local environmental suitability enabled almost a doubling in forest carbon sink potential. Progressive forestation of this area can fix a considerable amount of CO and compensate for the carbon sink decline in existing forests. Altogether, the entire forest ecosystem can support a persistent biophysical carbon sink potential of 0.4 Pg C y by 2060 and 0.2 Pg C y by 2100, offsetting 7 to 14% of the current national fossil CO emissions. Our research provides an example of building a forestation roadmap toward a sustained forest carbon sink, which creates a critical time window for the emission cuts required by the goal of carbon neutrality.
Topics: Ecosystem; Trees; Carbon; Carbon Dioxide; Forests; China; Carbon Sequestration
PubMed: 37782782
DOI: 10.1073/pnas.2304988120 -
International Journal of Molecular... Oct 2023Materials with a "nano" structure are increasingly used in medicine and biotechnology as drug delivery systems, bioimaging agents or biosensors in the monitoring of... (Review)
Review
Materials with a "nano" structure are increasingly used in medicine and biotechnology as drug delivery systems, bioimaging agents or biosensors in the monitoring of toxic substances, heavy metals and environmental variations. Furthermore, in the food industry, they have found applications as detectors of food adulteration, microbial contamination and even in packaging for monitoring product freshness. Carbon dots (CDs) as materials with broad as well as unprecedented possibilities could revolutionize the economy, if only their synthesis was based on low-cost natural sources. So far, a number of studies point to the positive possibilities of obtaining CDs from natural sources. This review describes the types of carbon dots and the most important methods of obtaining them. It also focuses on presenting the potential application of carbon dots in biotechnology and food technology.
Topics: Carbon; Quantum Dots; Drug Delivery Systems; Biotechnology; Food Technology
PubMed: 37834430
DOI: 10.3390/ijms241914984 -
Molecules (Basel, Switzerland) May 2024Polyhydroxyalkanoates (PHAs) are intracellular biopolymers that microorganisms use for energy and carbon storage. They are mechanically similar to petrochemical plastics... (Review)
Review
Polyhydroxyalkanoates (PHAs) are intracellular biopolymers that microorganisms use for energy and carbon storage. They are mechanically similar to petrochemical plastics when chemically extracted, but are completely biodegradable. While they have potential as a replacement for petrochemical plastics, their high production cost using traditional carbon sources remains a significant challenge. One potential solution is to modify heterotrophic PHA-producing strains to utilize alternative carbon sources. An alternative approach is to utilize methylotrophic or autotrophic strains. This article provides an overview of bacterial strains employed for PHA production, with a particular focus on those exhibiting the highest PHA content in dry cell mass. The strains are organized according to their carbon source utilization, encompassing autotrophy (utilizing CO, CO) and methylotrophy (utilizing reduced single-carbon substrates) to heterotrophy (utilizing more traditional and alternative substrates).
Topics: Polyhydroxyalkanoates; Bacteria; Carbon
PubMed: 38792154
DOI: 10.3390/molecules29102293 -
The Science of the Total Environment Aug 2023Dissolved organic carbon (DOC) and particulate organic carbon (POC) play a fundamental role in biogeochemical cycles of freshwater ecosystems. However, the lack of...
Dissolved organic carbon (DOC) and particulate organic carbon (POC) play a fundamental role in biogeochemical cycles of freshwater ecosystems. However, the lack of readily available distributed models for carbon export has limited the effective management of organic carbon fluxes from soils, through river networks and to receiving marine waters. We develop a spatially semi-distributed mass balance modeling approach to estimate organic carbon flux at a sub-basin and basin scales, using commonly available data, to allow stakeholders to explore the impacts of alternative river basin management scenarios and climate change on riverine DOC and POC dynamics. Data requirements, related to hydrological, land-use, soil and precipitation characteristics are easily retrievable from international and national databases, making it appropriate for data-scarce basins. The model is built as an open-source plugin for QGIS and can be easily integrated with other basin scale decision support models on nutrient and sediment export. We tested the model in Piave river basin, in northeast Italy. Results show that the model reproduces spatial and temporal changes in DOC and POC fluxes in relation to changes in precipitation, basin morphology and land use across different sub-basins. For example, the highest DOC export were associated with both urban and forest land use classes and during months of elevated precipitation. We used the model to evaluate alternative land use scenarios and the impact of climate on basin level carbon export to Mediterranean.
Topics: Carbon; Ecosystem; Environmental Monitoring; Rivers; Fresh Water; Soil; Dust; Dissolved Organic Matter
PubMed: 37142038
DOI: 10.1016/j.scitotenv.2023.163840 -
Journal of Plant Physiology Apr 2024Root growth and development need proper carbon partitioning between sources and sinks. Photosynthesis products are unloaded from the phloem and enter the root meristem... (Review)
Review
Root growth and development need proper carbon partitioning between sources and sinks. Photosynthesis products are unloaded from the phloem and enter the root meristem cell by cell. While sugar transporters play a major role in phloem loading, phloem unloading occurs via the plasmodesmata in growing root tips. The aperture and permeability of plasmodesmata strongly influence symplastic unloading. Recent research has dissected the symplastic path for phloem unloading and identified several genes that regulate phloem unloading in the root. Callose turnover and membrane lipid composition alter the shape of plasmodesmata, allowing fine-tuning to adapt phloem unloading to the environmental and developmental conditions. Unloaded sugars act both as an energy supply and as signals to coordinate root growth and development. Increased knowledge of how phloem unloading is regulated enhances our understanding of carbon allocation in plants. In the future, it may be possible to modulate carbon allocation between sources and sinks in a manner that would contribute to increased plant biomass and carbon fixation.
Topics: Phloem; Plants; Biological Transport; Meristem; Carbon
PubMed: 38428153
DOI: 10.1016/j.jplph.2024.154203 -
Nature Communications Jun 2023The alkyne unit is a versatile building block in organic synthesis and the development of selective multifunctionalization of alkynes is an important object of research...
The alkyne unit is a versatile building block in organic synthesis and the development of selective multifunctionalization of alkynes is an important object of research in this field. Herein, we report an interesting gold-catalyzed, four-component reaction that achieves the oxo-arylfluorination or oxo-arylalkenylation of internal aromatic or aliphatic alkynes, efficiently breaking a carbon-carbon triple bond and forming four new chemical bonds. The reaction divergence can be controlled by site-directing functional groups in the alkynes; the presence of a phosphonate unit favors the oxo-arylfluorination, while the carboxylate motif benefits oxo-arylalkenylation. This reaction is enabled by an Au(I)/Au(III) redox coupling process using Selectfluor as both an oxidant and a fluorinating reagent. A wide range of structurally diverse α,α-disubstituted ketones, and tri- or tetra-substituted unsaturated ketones have been prepared in synthetically valuable yields and with excellent chemo-, regio- and stereoselectivity. The gram-scale preparation and late-stage application of complex alkynes have further enhanced their synthetic value.
Topics: Gold; Alkynes; Catalysis; Ketones; Carbon
PubMed: 37322071
DOI: 10.1038/s41467-023-39243-5 -
The Science of the Total Environment Mar 2024Biochar can be used for multifunctional applications including the improvement of soil health and carbon storage, remediation of contaminated soil and water resources,... (Review)
Review
Biochar can be used for multifunctional applications including the improvement of soil health and carbon storage, remediation of contaminated soil and water resources, mitigation of greenhouse gas emissions and odorous compounds, and feed supplementation to improve animal health. A healthy soil preserves microbial biodiversity that is effective in supressing plant pathogens and pests, recycling nutrients for plant growth, promoting positive symbiotic associations with plant roots, improving soil structure to supply water and nutrients, and ultimately enhancing soil productivity and plant growth. As a soil amendment, biochar assures soil biological health through different processes. First, biochar supports habitats for microorganisms due to its porous nature and by promoting the formation of stable soil micro-aggregates. Biochar also serves as a carbon and nutrient source. Biochar alters soil physical and chemical properties, creating optimum soil conditions for microbial diversity. Biochar can also immobilize soil pollutants and reduce their bioavailability that would otherwise inhibit microbial growth. However, depending on the pyrolysis settings and feedstock resources, biochar can be comprised of contaminants including polycyclic aromatic hydrocarbons and potentially toxic elements that can inhibit microbial activity, thereby impacting soil health.
Topics: Soil; Charcoal; Carbon; Environmental Pollution; Soil Pollutants
PubMed: 38157897
DOI: 10.1016/j.scitotenv.2023.169585 -
Clinical and Translational Medicine Jan 2024One-carbon (1C) metabolism is a metabolic network that plays essential roles in biological reactions. In 1C metabolism, a series of nutrients are used to fuel metabolic... (Review)
Review
BACKGROUND
One-carbon (1C) metabolism is a metabolic network that plays essential roles in biological reactions. In 1C metabolism, a series of nutrients are used to fuel metabolic pathways, including nucleotide metabolism, amino acid metabolism, cellular redox defence and epigenetic maintenance. At present, 1C metabolism is considered the hallmark of cancer. The 1C units obtained from the metabolic pathways increase the proliferation rate of cancer cells. In addition, anticancer drugs, such as methotrexate, which target 1C metabolism, have long been used in the clinic. In terms of immunotherapy, 1C metabolism has been used to explore biomarkers connected with immunotherapy response and immune-related adverse events in patients.
METHODS
We collected numerous literatures to explain the roles of one-carbon metabolism in cancer immunotherapy.
RESULTS
In this review, we focus on the important pathways in 1C metabolism and the function of 1C metabolism enzymes in cancer immunotherapy. Then, we summarise the inhibitors acting on 1C metabolism and their potential application on cancer immunotherapy. Finally, we provide a viewpoint and conclusion regarding the opportunities and challenges of targeting 1C metabolism for cancer immunotherapy in clinical practicability in the future.
CONCLUSION
Targeting one-carbon metabolism is useful for cancer immunotherapy.
Topics: Humans; Neoplasms; Antineoplastic Agents; Metabolic Networks and Pathways; Carbon
PubMed: 38279895
DOI: 10.1002/ctm2.1521