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1.
Sci Total Environ ; 954: 176503, 2024 Sep 27.
Article in English | MEDLINE | ID: mdl-39343402

ABSTRACT

Methane (CH4) and nitrous oxide (N2O) are critical biogenic greenhouse gases (GHGs) with global warming potentials substantially greater than that of carbon dioxide (CO2). The exchange of these gases in tropical forests, particularly via foliar processes, remains poorly understood. We quantified foliar CH4 and N2O fluxes among tropical tree species and examined their potential association with the leaf economics spectrum (LES) traits. Sampling within Lawachara National Park, Bangladesh, we used in-situ measurements of foliar CH4 and N2O fluxes employing off-axis integrated cavity output spectroscopy (CH4, CO2 and H2O) and optical feedback-cavity enhanced absorption spectroscopy (N2O) analyzers. Leaves were measured under dark, low, and high (0, 100, and 1000 µmol·m-2·s-1) light conditions. Surveyed tree species exhibited both net foliar uptake and efflux of CH4, with a mean flux not different from zero, suggesting negligible net foliar emissions at the stand level. Plant families showed differences in CH4, but not N2O fluxes. Consistent efflux was observed for N2O, with a mean of 0.562 ± 0.060 pmol·m-2·s-1. Pioneer species exhibited a higher mean N2O flux (0.81 ± 0.17 pmol·m-2·s-1) compared to late-successional species (0.37 ± 0.05 pmol·m-2·s-1). Pioneer species also showed a trend toward a higher mean CH4 flux (0.24 ± 0.21 nmol·m-2·s-1) compared to mid-successional (-0.01 ± 0.26 nmol·m-2·s-1) and late-successional species (-0.05 ± 0.28 nmol·m-2·s-1). Moreover, among all leaf traits within the leaf economic spectrum, a significant positive relationship was observed between leaf N2O flux and total leaf nitrogen. Our results suggest that pioneer tree species significantly contribute to net CH4 and N2O emissions, potentially counteracting the carbon sequestration benefits in regenerating tropical forests. These findings indicate that accurate GHG budgeting should include direct measurements of foliar CH4 and N2O fluxes. Moreover, the results suggest that forest conservation and management strategies that prioritize late successional species will better mitigate GHG emissions.

2.
bioRxiv ; 2024 Sep 08.
Article in English | MEDLINE | ID: mdl-39282428

ABSTRACT

Alveolar macrophages (AMs) are key mediators of lung function and are potential targets for therapies during respiratory infections. TGFß is an important regulator of AM differentiation and maintenance, but how TGFß directly modulates the innate immune responses of AMs remains unclear. This shortcoming prevents effective targeting of AMs to improve lung function in health and disease. Here we leveraged an optimized ex vivo AM model system, fetal-liver derived alveolar-like macrophages (FLAMs), to dissect the role of TGFß in AMs. Using transcriptional analysis, we first globally defined how TGFß regulates gene expression of resting FLAMs. We found that TGFß maintains the baseline metabolic state of AMs by driving lipid metabolism through oxidative phosphorylation and restricting inflammation. To better understand inflammatory regulation in FLAMs, we next directly tested how TGFß alters the response to TLR2 agonists. While both TGFß (+) and TGFß (-) FLAMs robustly responded to TLR2 agonists, we found an unexpected activation of type I interferon (IFN) responses in FLAMs and primary AMs in a TGFß-dependent manner. Surprisingly, mitochondrial antiviral signaling protein and the interferon regulator factors 3 and 7 were required for IFN production by TLR2 agonists. Together, these data suggest that TGFß modulates AM metabolic networks and innate immune signaling cascades to control inflammatory pathways in AMs.

3.
Ther Adv Med Oncol ; 16: 17588359241273053, 2024.
Article in English | MEDLINE | ID: mdl-39220298

ABSTRACT

Background: The prognostic implications of tumor mutational burden (TMB) and programmed death ligand 1 (PD-L1) expression are poorly studied in hematologic malignancies. Objectives: This study aimed to better understand the characteristics and prognostic value of TMB and PD-1/PD-L1 in hematologic malignancies. Design: This real-world study was conducted among patients with hematologic malignancies who had next-generation sequencing (NGS) (Foundation Medicine) at the University of California San Diego Moores Cancer Center (2014-2018). Methods: TMB was measured by NGS. PD-L1 expression (tumor proportion score, TPS) was measured by immunohistochemistry (classified as high (⩾50%), low (1-49%), and negative (<1%)). Data was curated from the electronic medical records. Results: In 388 evaluable patients, the most common diagnoses were B-cell non-Hodgkin lymphoma (NHL) (35%) and Philadelphia chromosome-negative myeloproliferative disorders (16%). Median TMB was 1.6 mutations/Mb (range, 0-46.83). Forty-eight patients (12%) had TMB ⩾10 mutations/Mb, 90% of which were B-cell or T-cell NHL. In 85 samples with available PD-L1 scores, 11 were high; 26, low; and 48, no tumor cell expression. PD-L1 TPS positive (⩾1%) was most common in T-cell NHL (7/9 (77%) cases) followed by B-cell NHL (21/51 (41%) cases). TMB ⩾4 mutations/Mb and PD-L1 score ⩾1% were significantly associated with shorter overall survival (OS) from diagnosis, with hazard ratio (HR) = 1.46 (p = 0.02, 95% confidence interval (CI) 1.05-2.03) and HR = 2.11 (p = 0.04, 95% CI 1.04-4.30), respectively; the relationship was more pronounced when PD-L1 ⩾50% versus <50% was used (HR = 2.80, p = 0.02, 95% CI 1.19-6.59). Higher TMB and higher PD-L1 positivity correlation were significant but weak (Pearson correlation coefficient R 2 = 0.04, p = 0.04). Conclusion: TMB ⩾4 mutations/Mb and positive PD-L1 TPS are poor prognostic factors, correlating with shorter OS across hematologic malignancies. Trial registration: ClinicalTrials.gov NCT02478931.

4.
Environ Sci Pollut Res Int ; 31(31): 43874-43895, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38910184

ABSTRACT

Use of waste wood biomass for bioenergy produces wood ash as a by-product; this ash is typically landfilled, but can potentially play an important role in soil improvement and forest restoration. In particular, high-carbon wood ash biochar (HCWAB) could supply nutrients, improve substrate water-holding capacity and pH, and emulate the ecosystem benefits of wildfire residues. Thickened tailings sites at metal mines across Canada are subject to stringent restoration regulations that entail planting of native trees to promote rapid reforestation. While HCWAB may prove beneficial in this context, field trials have been very limited to date. We conducted a large-scale, replicated field trial on sand-capped tailings at an operational gold mine in the Canadian boreal forest to assess the impact of HCWAB (at dosages of 0, 6.4, 12.8, and 19.1 t/ha) on survival and growth of four native tree species, as well as substrate chemical properties and element uptake in tree tissues. After 2 years, the survival of planted, native trees was highest at low to moderate application rates; HCWAB dosages above 13 t/ha presented reduced tree survival to levels comparable to unamended substrates. Tree growth was higher across all HCWAB doses relative to growth in samples planted on untreated substrates; tree species and initial size also had large impacts on final tree survival and aboveground growth. The survival of Betula papyrifera was significantly higher than other species, while smaller transplanted trees in general survived in greater numbers compared to larger size classes. Volunteer herbaceous vegetation significantly increased at the higher HCWAB application dosages and tree performance was negatively correlated with vegetation cover, consistent with a resource competition effect. HCWAB additions to sand-capped mine tailings did not significantly alter tree tissue concentrations or substrate availability of potentially toxic metals (Cd, Cu, Al). We conclude that low to moderate dosages of HCWAB on sand-capped tailings, particularly between 6.4 and 12.8 t/ha, may offer benefits to early tree survival, growth, and substrate nutrient status without causing significant risks of phytotoxicity and recommend future field trials focus on strategies to reduce tree competition with competing vegetation.


Subject(s)
Charcoal , Mining , Trees , Wood , Charcoal/chemistry , Wood/chemistry , Sand , Carbon , Soil/chemistry , Canada
5.
Biochar ; 6(1): 51, 2024.
Article in English | MEDLINE | ID: mdl-38799720

ABSTRACT

Although addition of pyrolyzed organic materials (biochars) to soil generally results in increased growth and physiological performance of plants, neutral and negative responses have also commonly been detected. Toxicity of organic compounds generated during pyrolysis, sorbed by biochars, and then released into the soil solution, has been implicated as a possible mechanism for such negative effects. Conversely, water-soluble biochar constituents have also been suggested to have "hormetic" effects (positive effects on plants at low concentrations); however, no specific compounds responsible have been identified. We investigated the relative phytotoxicity-and possible hormetic effects-of 14 organic compounds common in aqueous extracts of freshly produced lignocellulosic biochars, using seed germination bioassays. Of the compounds examined, volatile fatty acids (VFAs: acetic, propionic, butyric, valeric, caproic, and 2-ethylbutyric acids) and phenol, showed acute phytotoxicity, with germination-based ED50 values of 1-30 mmol L-1, and 2-ethylbutyric acid showed ED50 values of 0.1-1.0 mmol L-1. Other compounds (benzene, benzoic acid, butanone, methyl salicylate, toluene, and 2,4-di-tert-butylphenol) showed toxic effects only at high concentrations close to solubility limits. Although phytotoxic at high concentrations, valeric and caproic acid also showed detectable hormetic effects on seedlings, increasing radicle extension by 5-15% at concentrations of ~ 0.01-0.1 mmol L-1. These data support the hypothesis that VFAs are the main agents responsible for phytotoxic effects of lignocellulosic biochar leachates, but that certain VFAs also have hormetic effects at low concentrations and may contribute to positive effects of biochar leachates on early plant development in some cases. Supplementary Information: The online version contains supplementary material available at 10.1007/s42773-024-00339-w.

6.
Sci Total Environ ; 930: 172666, 2024 Jun 20.
Article in English | MEDLINE | ID: mdl-38653415

ABSTRACT

The net effect of forest disturbances, such as fires and harvesting, on soil greenhouse gas fluxes is determined by their impacts on both biological and physical factors, as well as the temporal dynamics of these effects post-disturbance. Although harvesting and fire may have distinct effects on soil carbon (C) dynamics, the temporal patterns in soil CO2 and CH4 fluxes and the potential differences between types of disturbances, remain poorly characterized in boreal forests. In this study, we measured soil CO2 and CH4 fluxes using a off-axis integrated cavity output spectroscopy system in snow-free seasons over two years in post-harvest and post-fire chronosequence sites within a mixedwood boreal forest in northwestern Ontario, Canada. Soil CO2 efflux showed a post-disturbance peak, with differing dynamics depending on the disturbance type: post-harvest stands exhibited a nearly tenfold increase (from ∼1 to ∼11 µmol CO2.m-2.s-1) from 1 to 9-10 years post-disturbance, followed by a steep decline; post-fire stands showed a more gradual increase, peaking at ∼6-7.2 µmol CO2.m-2.s-1 after ∼12-15 years. The youngest post-harvest stands were net sources of CH4,whereas post-fire stands were never net CH4 sources. In both disturbance types, the strength of the CH4 sink increased with stand age, approaching ∼2.4 nmol.m-2.s-1 by 15 years post-disturbance. Volumetric water content, bulk density, litter depth, and pH were significant predictors of CO2 fluxes; for CH4 fluxes, litter depth, pH, and the interaction of VWC and soil temperature were significant predictors in both disturbance types, with EC also showing a relationship in post-harvest stands. Our findings indicate that while soil CH4 oxidation rapidly recovers following disturbance, both post-harvest and post-fire stands show a multi-decade release of soil CO2 that is too large to be offset by C gains over this period.

7.
Sci Total Environ ; 922: 171302, 2024 Apr 20.
Article in English | MEDLINE | ID: mdl-38428607

ABSTRACT

Green roofs have been increasingly used to improve stormwater management, but poor vegetation performance on roof systems, varying with vegetation type, can degrade discharge quality. Biochar has been suggested as an effective substrate additive for green roofs to improve plant performance and discharge quality. However, research on the effects of biochar and vegetation on discharge quality in the long term is lacking and the underlying mechanisms involved are unclear. We examined the effects of biochar amendment and vegetation on discharge quality on organic-substrate green roofs with pre-grown sedum mats and direct-seeded native plants for three years and investigated the key factors influencing discharge quality. Sedum mats reduced the leaching of nutrients and particulate matter by 6-64% relative to native plants, largely due to the higher initial vegetation cover of the former. Biochar addition to sedum mat green roofs resulted in the best integrated water quality due to enhanced plant cover and sorption effects. Structural equation modeling revealed that nutrient leaching was primarily influenced by rainfall depth, time, vegetation cover, and substrate pH. Although biochar-amended sedum mats showed better discharge quality from organic-substrate green roofs, additional ecosystem services may be provided by native plants, suggesting future research to optimize plant composition and cover and biochar properties for sustainable green roofs.


Subject(s)
Charcoal , Sedum , Water Quality , Ecosystem , Conservation of Natural Resources/methods , Rain , Plants
8.
PNAS Nexus ; 3(1): pgad428, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38234583

ABSTRACT

There has been a recent surge of interest in UTe2 due to its unconventional magnetic field (H)-reinforced spin-triplet superconducting phases persisting at fields far above the simple Pauli limit for H∥[010]. Magnetic fields in excess of 35 T then induce a field-polarized magnetic state via a first-order-like phase transition. More controversially, for field orientations close to H∥[011] and above 40 T, electrical resistivity measurements suggest that a further superconducting state may exist. However, no Meissner effect or thermodynamic evidence exists to date for this phase making it difficult to exclude alternative scenarios. In this paper, we describe a study using thermal, electrical, and magnetic probes in magnetic fields of up to 55 T applied between the [010] (b) and [001] (c) directions. Our MHz conductivity data reveal the field-induced state of low or vanishing electrical resistance; our simultaneous magnetocaloric effect measurements (i.e. changes in sample temperature due to changing magnetic field) show the first definitive evidence for adiabaticity and thermal behavior characteristic of bulk field-induced superconductivity.

9.
Eur J Orthop Surg Traumatol ; 34(1): 237-242, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37433971

ABSTRACT

PURPOSE: Pilon fractures are often complex injuries involving severe soft tissue injury. Studies have shown pilon fractures may entrap soft tissue structures between fracture fragments. Staged fixation of pilon fractures with spanning external fixation (SEF) is important for soft tissue rest and plays an important role in the management of these injuries. While SEF has been shown to promote soft tissue rest prior to definitive fixation, no studies have shown the effect SEF has on entrapped structures (ES). The purpose of this study was to evaluate how SEF effects ES in pilon fractures. METHODS: A retrospective review of 212 pilon fractures treated at our institution between 2010 and 2022 was performed. Patients with a CT scan pre-SEF and post-SEF met inclusion criteria. CTs were reviewed to characterize ES in pre- and post-SEF imaging. RESULTS: Of the 19 patients with ES identified on CT pre-SEF, seven (36.8%) had full release of ES post-SEF and 12 (63.2%) had no release of ES. The posterior tibial tendon was the most commonly ES and remained entrapped in 62.5% of cases. Only 25% of 43-C3 fractures had release of ES post-SEF, while 100% of 43-C1 and 43-C2 fractures demonstrated complete release of ES post-SEF. CONCLUSION: Entrapped structures in pilon fractures are likely to remain entrapped post-SEF, with only one-third of our cohort demonstrating release. In 43-C3 patterns, if ES are identified on CT pre-SEF, surgeons should consider addressing these either through mini open versus open approaches at the time of SEF as they are likely to remain entrapped post-SEF.


Subject(s)
Ankle Fractures , Ankle Injuries , Tibial Fractures , Humans , Fracture Fixation, Internal , Fracture Fixation , External Fixators , Treatment Outcome , Ankle Injuries/surgery , Tibial Fractures/diagnostic imaging , Tibial Fractures/surgery , Ankle Fractures/diagnostic imaging , Ankle Fractures/surgery , Retrospective Studies
10.
J Orthop Trauma ; 38(1): e15-e19, 2024 01 01.
Article in English | MEDLINE | ID: mdl-37876218

ABSTRACT

OBJECTIVES: The objective of this study was to define the danger zone at which the anterior tibial artery (ATA) is at risk during anterolateral plating of the distal tibia using a novel 3D computed tomography angiography (CTA) modeling technique. METHODS: 116 patients (232 lower extremities) who underwent lower extremity CTAs between April 2020 and April 2022 were identified. Those with lower extremity trauma, evidence of a previously healed tibial fracture, or poor visualization of the ATA were excluded. The remaining 150 lower extremities (92 patients) were modeled with an anterolateral distal tibia plate using Sectra IDS7 software. The distance of the ATA from bony landmarks was measured perpendicular to the level at which the vessel intersected the plate. RESULTS: The ATA intersected the plate proximally at a mean distance of 10.5 cm (95% confidence intervals, 10.2-10.9) and at a mean distance of 4.6 cm (95% confidence intervals, 4.4-4.9) distally from the central tibial plafond. The ATA intersected with the plate as far distal as hole number 1 and as proximal as hole 14 of the plate. The greatest injury risk was associated with plate holes 3-8. In this region, the artery was at risk in 46-99 percent of specimens. CONCLUSIONS: The ATA is at risk when screws are placed percutaneously in an anterolateral distal tibia plate. The artery can be as close as 4.4 cm and as far as 10.9 cm proximal to the tibial plafond when crossing the plate, correlating to a risk of injury to the ATA at plate holes 1 through 14.


Subject(s)
Tibia , Tibial Fractures , Humans , Tibia/diagnostic imaging , Tibia/surgery , Tibia/blood supply , Tibial Arteries/diagnostic imaging , Tibial Arteries/surgery , Tibial Arteries/injuries , Tibial Fractures/diagnostic imaging , Tibial Fractures/surgery , Fracture Fixation, Internal/methods , Tomography, X-Ray Computed , Angiography , Bone Plates
11.
J Environ Manage ; 350: 119068, 2024 Jan 15.
Article in English | MEDLINE | ID: mdl-37821334

ABSTRACT

Deforestation in the Amazon has resulted in large areas of depleted soils on abandoned pastures and agricultural sites that present a restoration challenge central to protecting biodiversity and ecosystem function in the region. Biochar - charcoal made from waste materials - can improve soil physical, chemical, and biological properties, but the few tropical field trials to date do not give consistent results regarding tree growth. This study presents three years of soil performance and tree growth of a secondary forest shading nontimber forest product (NTFP) plantations of Ocotea quixos (Lauraceae), Myroxylon balsamum (Fabaceae), and their mixture. Open kiln and traditional mound biochars were added at 10 t ha-1 at two sites with contrasting soil types. Biochar additions resulted in pronounced effects on soil properties that varied over time and with depth in the soil profile. Biochar additions generally increased soil organic matter, electrical conductivity, and plant nutrients (in particular K, Ca, and N), but there were interactive effects of NTFP treatments, and stronger responses on the poorer soil type. Biochar amendments resulted in increased tree growth, with a 29 ± 12% increase in aboveground biomass (AGB) on plots amended with kiln biochar and a 23 ± 9% increase in plots with mound biochar compared to controls. Tree species also varied in growth responses to biochar additions, with the largest increases observed in Jaccaranda copaia and Piptocoma discolor. Significant interactions between biochar and NTFP treatments were also seen for tree growth responses, such as Cecropia spp., which only showed increased biomass on mound biochar plots planted with Ocotea quixos. Overall, our results demonstrate a stronger effect of biochar in less favorable soil conditions, and an overriding effect of the legume NTFP in richer soils, and suggest that additions of biochar and legumes are important options to increase productivity and ecological resilience in tropical forest restoration.


Subject(s)
Fabaceae , Soil , Soil/chemistry , Ecosystem , Charcoal/chemistry , Ecuador , Forests , Trees , Vegetables
12.
Nutrients ; 15(21)2023 Nov 05.
Article in English | MEDLINE | ID: mdl-37960343

ABSTRACT

Type 2 diabetes mellitus (T2DM) remains a global health concern. Emerging clinical trial (CT) evidence suggests that probiotic intervention may promote a healthy gut microbiome in individuals with T2DM, thereby improving management of the disease. This systematic literature review summarizes thirty-three CTs investigating the use of oral probiotics for the management of T2DM. Here, twenty-one studies (64%) demonstrated an improvement in at least one glycemic parameter, while fifteen studies (45%) showed an improvement in at least one lipid parameter. However, no article in this review was able to establish a uniform decrease in glycemic, lipid, or blood pressure profiles. The lack of consistency across the studies may be attributed to differences in probiotic composition, duration of probiotic consumption, and probiotic dose. An interesting finding of this literature review was the beneficial trend of metformin and probiotic co-administration. Here, patients with T2DM taking metformin demonstrated enhanced glycemic control via the co-administration of probiotics. Taken together, the overall positive findings reported across the studies in combination with minimal adverse effects constitute ground for further quality CTs. This review provides recommendations for future CTs that may address the shortcomings of the current studies and help to extract useful data from future investigations of the use of probiotics in T2DM management.


Subject(s)
Diabetes Mellitus, Type 2 , Metformin , Probiotics , Humans , Diabetes Mellitus, Type 2/drug therapy , Blood Glucose , Probiotics/therapeutic use , Lipids
13.
Environ Sci Technol ; 57(41): 15475-15486, 2023 10 17.
Article in English | MEDLINE | ID: mdl-37788297

ABSTRACT

Urbanization has degraded ecosystem services on a global scale, and cities are vulnerable to long-term stresses and risks exacerbated by climate change. Green infrastructure (GI) has been increasingly implemented in cities to improve ecosystem functions and enhance city resilience, yet GI degradation or failure is common. Biochar has been recently suggested as an ideal substrate additive for a range of GI types due to its favorable properties; however, the generality of biochar benefits the GI ecosystem function, and the underlying mechanisms remain unclear. Here, we present a global meta-analysis and synthesis and demonstrate that biochar additions pervasively benefit a wide range of ecosystem functions on GI. Biochar applications were found to improve substrate water retention capacity by 23% and enhance substrate nutrients by 12-31%, contributing to a 33% increase in plant total biomass. Improved substrate physicochemical properties and plant growth together reduce discharge water volume and improve discharge water quality from GI. In addition, biochar increases microbial biomass on GI by ∼150% due to the presence of biochar pores and enhanced microbial growth conditions, while also reducing CO2 and N2O emissions. Overall results suggest that biochar has great potential to enhance GI ecosystem functions as well as urban sustainability and resilience.


Subject(s)
Ecosystem , Sustainable Growth , Cities , Charcoal/chemistry , Soil/chemistry
14.
PLoS One ; 18(7): e0288291, 2023.
Article in English | MEDLINE | ID: mdl-37463169

ABSTRACT

Declining tree health status due to pollutant impacts and nutrient imbalance is widespread in urban forests; however, chemical fertilizer use is increasingly avoided to reduce eutrophication impacts. Biochar (pyrolyzed organic waste) has been advocated as an alternative soil amendment, but biochar alone generally reduces plant N availability. The combination of biochar and either organic forms of N or Plant Growth Promoting Microbes (PGPMs) as biofertilizers may address these challenges. We examined the effects of two wood biochar types with Bacillus velezensis and an inactivated yeast (IY) biofertilizer in a three-month factorial greenhouse experiment with Acer saccharinum L. (silver maple) saplings grown in a representative urban soil. All treatments combining biochars with biofertilizers significantly increased sapling growth, with up to a 91% increase in biomass relative to controls. Growth and physiological responses were closely related to nutrient uptake patterns, with nutrient vector analyses indicating that combined biochar and biofertilizer treatments effectively addressed nutrient limitations of both macronutrients (N, P, K, Mg, Ca), and micronutrients (B, Fe, Mn, Mo, Na, S, and Zn). Biochar-biofertilizer treatments also reduced foliar concentrations of Cu, suggesting potential to mitigate toxic metal impacts common in urban forestry. We conclude that selected combinations of biochar and biofertilizers have substantial promise to address common soil limitations to tree performance in urban settings.


Subject(s)
Acer , Soil Pollutants , Charcoal , Nutrients , Soil , Trees
15.
Sci Total Environ ; 901: 165861, 2023 Nov 25.
Article in English | MEDLINE | ID: mdl-37516177

ABSTRACT

Unique properties of biochar render it appealing for revegetating and decontaminating historic, barren, and chemically complex mine tailings. Bottom ash from bioenergy facilities can contain high levels of charcoal residue, and thus qualify as a type of biochar; the wide availability of this material at low cost makes it of particular interest in the context of tailings remediation. Nevertheless, bottom ash is variable and often contains residual toxic metal/loids that could be phytoabsorbed into plant tissues. We implemented a replicated field trial on historic contaminated metal mine tailings in Northern Ontario (Canada) over a range of high­carbon wood ash biochar (HCWAB) dosages (0-30 t/ha) to evaluate tree and substrate responses. Sapling survivorship and aboveground biomass growth were quantified over a 4-year period; substrate chemical parameters were measured using acid-digestion and ICP-MS, as well as ion exchange resin probes. To assess elemental composition of sapling tissues, we used electron probe microanalysis combined with laser-ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) on intact samples across the range of dosages applied. Survival and growth of saplings peaked at mid-range ash dosages of 3-6 t/ha. Similarly, substrate ion availability of P, K, and Zn were stable at lower dosages, but increased above 6 t/ha. The trace amounts of toxic metal/loids of concern measured in wood ash (As, Cd, Cu, and Pb) did not result in significantly increased sapling tissue concentrations at low to moderate dosages, but in some cases tissue contaminant levels were elevated at the highest dosage examined (30 t/ha). Our findings highlight the potential for high­carbon wood ash biochar to be used for metal mine restoration at low to moderate dosages.

16.
Infect Immun ; 91(7): e0006023, 2023 07 18.
Article in English | MEDLINE | ID: mdl-37314361

ABSTRACT

Immune networks that control antimicrobial and inflammatory mechanisms have overlapping regulation and functions to ensure effective host responses. Genetic interaction studies of immune pathways that compare host responses in single and combined knockout backgrounds are a useful tool to identify new mechanisms of immune control during infection. For disease caused by pulmonary Mycobacterium tuberculosis (Mtb) infections, which currently lacks an effective vaccine, understanding the genetic interactions between protective immune pathways may identify new therapeutic targets or disease-associated genes. Previous studies have suggested a direct link between the activation of NLRP3-Caspase1 inflammasome and the NADPH-dependent phagocyte oxidase complex during Mtb infection. Loss of the phagocyte oxidase complex alone resulted in increased activation of Caspase1 and IL-1ß production during Mtb infection, resulting in failed disease tolerance during the chronic stages of disease. To better understand this interaction, we generated mice lacking both Cybb, a key subunit of the phagocyte oxidase, and Caspase1/11. We found that ex vivo Mtb infection of Cybb-/-Caspase1/11-/- macrophages resulted in the expected loss of IL-1ß secretion but an unexpected change in other inflammatory cytokines and bacterial control. Mtb infected Cybb-/-Caspase1/11-/- mice rapidly progressed to severe TB, succumbing within 4 weeks to disease characterized by high bacterial burden, increased inflammatory cytokines, and the recruitment of granulocytes that associated with Mtb in the lungs. These results uncover a key genetic interaction between the phagocyte oxidase complex and Caspase1/11 that controls protection against TB and highlight the need for a better understanding of the regulation of fundamental immune networks during Mtb infection.


Subject(s)
Mycobacterium tuberculosis , Tuberculosis, Pulmonary , Tuberculosis , Animals , Mice , Oxidoreductases/metabolism , Tuberculosis/genetics , Phagocytes , Cytokines/metabolism
17.
Front Oncol ; 13: 1171278, 2023.
Article in English | MEDLINE | ID: mdl-37213298

ABSTRACT

Background: Irreversible electroporation (IRE) has been previously investigated in preclinical trials as a treatment for intracranial malignancies. Here, we investigate next generation high-frequency irreversible electroporation (H-FIRE), as both a monotherapy and a combinatorial therapy, for the treatment of malignant gliomas. Methods: Hydrogel tissue scaffolds and numerical modeling were used to inform in-vivo H-FIRE pulsing parameters for our orthotopic tumor-bearing glioma model. Fischer rats were separated into five treatment cohorts including high-dose H-FIRE (1750V/cm), low-dose H-FIRE (600V/cm), combinatorial high-dose H-FIRE + liposomal doxorubicin, low-dose H-FIRE + liposomal doxorubicin, and standalone liposomal doxorubicin groups. Cohorts were compared against a standalone tumor-bearing sham group which received no therapeutic intervention. To further enhance the translational value of our work, we characterize the local and systemic immune responses to intracranial H-FIRE at the study timepoint. Results: The median survival for each cohort are as follows: 31 days (high-dose H-FIRE), 38 days (low-dose H-FIRE), 37.5 days (high-dose H-FIRE + liposomal doxorubicin), 27 days (low-dose H-FIRE + liposomal doxorubicin), 20 days (liposomal doxorubicin), and 26 days (sham). A statistically greater overall survival fraction was noted in the high-dose H-FIRE + liposomal doxorubicin (50%, p = 0.044), high-dose H-FIRE (28.6%, p = 0.034), and the low-dose H-FIRE (20%, p = 0.0214) compared to the sham control (0%). Compared to sham controls, brain sections of rats treated with H-FIRE demonstrated significant increases in IHC scores for CD3+ T-cells (p = 0.0014), CD79a+ B-cells (p = 0.01), IBA-1+ dendritic cells/microglia (p = 0.04), CD8+ cytotoxic T-cells (p = 0.0004), and CD86+ M1 macrophages (p = 0.01). Conclusions: H-FIRE may be used as both a monotherapy and a combinatorial therapy to improve survival in the treatment of malignant gliomas while also promoting the presence of infiltrative immune cells.

18.
Ecol Appl ; 33(4): e2832, 2023 06.
Article in English | MEDLINE | ID: mdl-36864680

ABSTRACT

Many invasive and some native tree species in North America exhibit strong allelopathic effects that may contribute to their local dominance. Pyrogenic carbon (PyC; including soot, charcoal, and black carbon) is produced by the incomplete combustion of organic matter and is widespread in forest soils. Many forms of PyC have sorptive properties that can reduce the bioavailability of allelochemicals. We investigated the potential for PyC produced by controlled pyrolysis of biomass ("biochar" [BC]) to reduce the allelopathic effects of black walnut (Juglans nigra) and Norway maple (Acer platanoides), a common native tree species and a widespread invasive species in North America, respectively. Seedling growth of two native tree species (Acer saccharinum [silver maple] and Betula papyrifera [paper birch]) in response to leaf-litter-incubated soils was examined; litter incubation treatments included leaves of black walnut, Norway maple, and a nonallelopathic species (Tilia americana [American basswood]) in a factorial design with varying dosages; responses to the known primary allelochemical of black walnut (juglone) were also examined. Juglone and leaf litter of both allelopathic species strongly suppressed seedling growth. BC treatments substantially mitigated these effects, consistent with the sorption of allelochemicals; in contrast no positive effects of BC were observed in leaf litter treatments involving controls or additions of nonallelopathic leaf litter. Treatments of leaf litter and juglone with BC increased the total biomass of silver maple by ~35% and in some cases more than doubled the biomass of paper birch. We conclude that BCs have the capacity to largely counteract allelopathic effects in temperate forest systems, suggesting the effects of natural PyC in determining forest community structure, and also the applied use of BC as a soil amendment to mitigate allelopathic effects of invasive tree species.


Subject(s)
Charcoal , Trees , Charcoal/analysis , Silver/analysis , Soil , Seedlings , Plant Leaves/physiology
19.
bioRxiv ; 2023 Feb 11.
Article in English | MEDLINE | ID: mdl-36798180

ABSTRACT

Immune networks that control antimicrobial and inflammatory mechanisms have overlapping regulation and functions to ensure effective host responses. Genetic interaction studies of immune pathways that compare host responses in single and combined knockout backgrounds are a useful tool to identify new mechanisms of immune control during infection. For disease caused by pulmonary Mycobacterium tuberculosis infections, which currently lacks an effective vaccine, understanding genetic interactions between protective immune pathways may identify new therapeutic targets or disease-associated genes. Previous studies suggested a direct link between the activation of NLRP3-Caspase1 inflammasome and the NADPH-dependent phagocyte oxidase complex during Mtb infection. Loss of the phagocyte oxidase complex alone resulted in increased activation of Caspase1 and IL1ß production during Mtb infection, resulting in failed disease tolerance during the chronic stages of disease. To better understand this interaction, we generated mice lacking both Cybb , a key subunit of the phagocyte oxidase, and Caspase1/11 . We found that ex vivo Mtb infection of Cybb -/- Caspase1/11 -/- macrophages resulted in the expected loss of IL1ß secretion but an unexpected change in other inflammatory cytokines and bacterial control. Mtb infected Cybb -/- Caspase1/11 -/- mice rapidly progressed to severe TB, succumbing within four weeks to disease characterized by high bacterial burden, increased inflammatory cytokines, and the recruitment of granulocytes that associated with Mtb in the lungs. These results uncover a key genetic interaction between the phagocyte oxidase complex and Caspase1/11 that controls protection against TB and highlight the need for a better understanding of the regulation of fundamental immune networks during Mtb infection.

20.
Nanotechnology ; 34(15)2023 Feb 03.
Article in English | MEDLINE | ID: mdl-36657159

ABSTRACT

Novel heterostructures created by coupling one-dimensional semiconductor nanowires with a superconducting thin film show great potential toward next-generation quantum computing. Here, by growing high-crystalline SiGe nanowires on a NbTiN thin film, the resulting heterostructure exhibits Ohmic characteristics as well as a shift of the superconducting transition temperature (Tc). The structure was characterized at atomic resolution showing a sharp SiGe/NbTiN interface without atomic interdiffusion. Lattice spacing, as calculated from large-area x-ray diffraction experiments, suggests a potential preferredd-spacing matching between (200) NbTiN and (110) SiGe grains. The observed out-of-plane compressive strain within the NbTiN films coupled with SiGe nanowires explains the downward shift of the superconductivity behavior. The presented results post scientific insights toward functional heterostructures by coupling multi-dimensional materials, which could enable tunable superconductivity that benefits the quantum science applications.

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