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Heliyon Jul 2023Road dust cotains tire wear particles (TWPs) and a large amount of mineral particles (MPs). Given that tire tread in vehicles is mainly comprised of natural rubber (NR),...
Road dust cotains tire wear particles (TWPs) and a large amount of mineral particles (MPs). Given that tire tread in vehicles is mainly comprised of natural rubber (NR), isoprene and dipentene could be the main pyrogenic products stemmed from the thermolysis of NR. This offers a great chance to quantify the exact mass of TWP in road dust. As such, this study focused on the influence of MPs on the trends in thermolytic behaviors of NR using the resistive furnace (furnance) and Curie point pyrolyzers. This study confirmed that a reliable correlation in line with the formation of isoprene and dipentene could not be realized using the furnace type of a pyrolyzer. This means that employing the furnace type of a pyrolyzer in quantitification of TWPs could not be a viable and approproiate option due to the diverted thermolytic trends of NR due to differences in the heat transfer and adsoprtion of the pyrogenic products triggered by MPs. In the Curie point type of a pyrolyzer, the production rates of isoprene and dipentene were linearly responded to the mass of NR. The ferromagnetic substance in MPs could lead to the thermolytic trend change of NR. Thus, adopting the Curie point type of a pyrolyzer could be a viable option for quantification of TWPs in road dust when the effects of ferromagnetic substance are well neutralized.
PubMed: 37483690
DOI: 10.1016/j.heliyon.2023.e17796 -
Bulletin of Environmental Contamination... Dec 2023The whale shark (Rhincodon typus) is a filter-feeding organism that can be considered a sentinel species, and Bahía de los Ángeles (BLA) in the Gulf of California is...
The whale shark (Rhincodon typus) is a filter-feeding organism that can be considered a sentinel species, and Bahía de los Ángeles (BLA) in the Gulf of California is an important sighting site for these elasmobranchs. This filter-feeding organism can be considered a pollutant sampler from the marine environment. Persistent organic pollutants are toxic compounds with high mobility and environmental persistence, bioaccumulation and trophic transfer. Among these are polycyclic aromatic hydrocarbons (PAHs) and organochlorine pesticides (OCPs). The present work aimed to determine concentrations of PAHs and OCPs in whale shark skin biopsies, collected in 2021 at BLA. Mean detected levels of PAHs and OCPs were 279.4 ng/g dw (dry weight) and 1478.1 ng/g dw, respectively. Analysis of similarities between the ordered sizes (4.2-7.6 m) and the concentrations of PAHs and OCPs indicated no significant differences. Individual PAHs detected indicate pyrogenic and petrogenic sources; the presence of pesticides at levels higher than those of hydrocarbons may be related to agricultural activity in the areas surrounding the Baja California peninsula. This study is the first report of PAH levels in R. typus for the Gulf of California and Mexico.
Topics: Animals; Mexico; Environmental Monitoring; Persistent Organic Pollutants; Brazil; Los Angeles; Pesticides; Hydrocarbons, Chlorinated; Sharks; Polycyclic Aromatic Hydrocarbons; Biopsy; Water Pollutants, Chemical
PubMed: 38141110
DOI: 10.1007/s00128-023-03841-2 -
Oncology Letters Jul 2023Pyrotinib is a novel irreversible tyrosine kinase inhibitor targeting the human epidermal growth factor receptor (HER), whose efficacy in treating metastatic...
Pyrotinib is a novel irreversible tyrosine kinase inhibitor targeting the human epidermal growth factor receptor (HER), whose efficacy in treating metastatic HER2-positive (HER2) breast cancer has been confirmed. The present study aimed to explore the efficacy, safety and prognostic factors of pyrogenic-involved neoadjuvant therapy in patients with HER2 breast cancer. A total of 49 patients with HER2 breast cancer who received pyrotinib-neoadjuvant therapy were recruited. All patients received pyrotinib plus chemotherapy with or without trastuzumab neoadjuvant treatment for six cycles (21 days/cycle). Concerning the clinical response, 4 (8.2%), 36 (73.4%) and 9 (18.4%) patients achieved complete response, partial response and stable disease after 6-cycle pyrotinib-neoadjuvant treatment, respectively; the objective response rate and disease control rate reached 81.6 and 100.0%, respectively. Concerning the pathological response, 23 (46.9%), 12 (24.5%), 12 (24.5%) and 2 (4.1%) patients were evaluated as Miller-Payne grade 5, 4, 3 and 2, respectively. In addition, 23 (46.9%) patients achieved pathological complete response (pCR) in the breast tissue, 40 (81.6%) patients achieved pCR in lymph nodes, while 22 (44.9%) patients obtained total pCR (tpCR). Further multivariate logistic regression analysis demonstrated that pyrotinib plus trastuzumab and chemotherapy (vs. pyrotinib plus chemotherapy) was independently correlated with increased tpCR (P=0.048). The most frequent adverse events included diarrhea (81.6%), anemia (69.4%), nausea and vomiting (63.3%), and fatigue (51.0%). The majority of the adverse events were mild and controllable. In conclusion, pyrotinib-neoadjuvant therapy presented optimal efficacy and mild toxicity in patients with HER2 breast cancer, whose efficacy was affected by the combination treatment with trastuzumab.
PubMed: 37332338
DOI: 10.3892/ol.2023.13900 -
Scientific Reports Dec 2023The northeastern Pacific (NEP) Ocean spans the coast of British Columbia (Canada) and is impacted by anthropogenic activities including oil pipeline developments,...
The northeastern Pacific (NEP) Ocean spans the coast of British Columbia (Canada) and is impacted by anthropogenic activities including oil pipeline developments, maritime fossil fuel tanker traffic, industrial chemical effluents, agricultural and urban emissions in tandem with stormwater and wastewater discharges, and forest wildfires. Such events may expose surrounding marine environments to toxic polycyclic aromatic hydrocarbons (PAHs) and impact critical habitats of threatened killer whales (Orcinus orca). We analyzed skeletal muscle and liver samples from stranded Bigg's killer whales and endangered Southern Resident killer whales (SRKWs) for PAH contamination using LRMS. C3-phenanthrenes/anthracenes (mean: 632 ng/g lw), C4-dibenzothiophenes (mean: 334 ng/g lw), and C4-phenanthrenes/anthracenes (mean: 248 ng/g lw) presented the highest concentrations across all tissue samples. Diagnostic ratios indicated petrogenic-sourced contamination for SRKWs and pyrogenic-sourced burdens for Bigg's killer whales; differences between ecotypes may be attributed to habitat range, prey selection, and metabolism. A mother-fetus skeletal muscle pair provided evidence of PAH maternal transfer; low molecular weight compounds C3-fluorenes, dibenzothiophene, and naphthalene showed efficient and preferential exposure to the fetus. This indicates in-utero exposure of PAH-contamination to the fetus. Our results show that hydrocarbon-related anthropogenic activities are negatively impacting these top predators; preliminary data found here can be used to improve oil spill and other PAH pollution management and regulation efforts, and inform policy to conserve killer whale habitats in the NEP.
Topics: Animals; Polycyclic Aromatic Hydrocarbons; Whale, Killer; British Columbia; Phenanthrenes; Anthracenes; Environmental Monitoring
PubMed: 38114485
DOI: 10.1038/s41598-023-45306-w -
Environmental Science & Technology Dec 2023Methane (CH) is the second most important greenhouse gas, 27 times as potent as CO and responsible for >30% of the current anthropogenic warming. Globally, more than...
Methane (CH) is the second most important greenhouse gas, 27 times as potent as CO and responsible for >30% of the current anthropogenic warming. Globally, more than half of CH is produced microbially through methanogenesis. Pyrogenic black carbon possesses a considerable electron storage capacity (ESC) and can be an electron donor or acceptor for abiotic and microbial redox transformation. Using wood-derived biochar as a model black carbon, we demonstrated that air-oxidized black carbon served as an electron acceptor to support anaerobic oxidation of organic substrates, thereby suppressing CH production. Black carbon-respiring bacteria were immediately active and outcompeted methanogens. Significant CH did not form until the bioavailable electron-accepting capacity of the biochar was exhausted. An experiment with labeled acetate (CHCOO) yielded 1:1 CH and CO without biochar and predominantly CO with biochar, indicating that biochar enabled anaerobic acetate oxidation at the expense of methanogenesis. Methanogens were enriched following acetate fermentation but only in the absence of biochar. The electron balance shows that approximately half (∼2.4 mmol/g) of biochar's ESC was utilized by the culture, corresponding to the portion of the ESC > +0.173 V (vs SHE). These results provide a mechanistic basis for quantifying the climate impact of black carbon and developing ESC-based applications to reduce CH emissions from biogenic sources.
Topics: Electrons; Carbon Dioxide; Charcoal; Oxidants; Methane; Acetates; Soil
PubMed: 38038997
DOI: 10.1021/acs.est.3c05830 -
Biological Trace Element Research Sep 2023Conditions associated with selenium (Se) and/or vitamin E (VitE) deficiency are still being reported in high-yielding pigs fed the recommended amounts. Here, the dietary...
Conditions associated with selenium (Se) and/or vitamin E (VitE) deficiency are still being reported in high-yielding pigs fed the recommended amounts. Here, the dietary effects of Se source (sodium selenite, NaSe, 0.40 or 0.65 mg Se/kg; L-selenomethionine, SeMet, 0.19 or 0.44 mg Se/kg; a NaSe-SeMet mixture, SeMix, 0.44-0.46 mg Se/kg) and VitE concentration (27, 50-53 or 101 mg/kg) on the antioxidant status of finisher pigs were compared with those in pigs fed non-Se-supplemented diets (0.08-0.09 mg Se/kg). Compared to NaSe-enriched diets, SeMet-supplemented diets resulted in significantly (p < 0.0018) higher plasma concentrations of total Se (14-27%) and selenospecies (GPx3, SelP, SeAlb; 7-83%), significantly increased the total Se accumulation in skeletal muscles, myocardium, liver and brain (10-650%), and enhanced the VitE levels in plasma (15-74%) and tissues (8-33%) by the end of the 80-day trial, proving better Se distribution and retention in pigs fed organic Se. Injecting lipopolysaccharide (LPS) intravenously half-way into the trial provoked a pyrogenic response in the pigs followed by a rapid increase of inorganic Se after 5-12 h, a drastic drop of SeMet levels between 12 and 24 h that recovered by 48 h, and a small increase of SeCys by 24-48 h, together with a gradual rise of GPx3, SelP and SeAlb in plasma up to 48 h. These changes in Se speciation in plasma were particularly significant (0.0024 > p > 0.00007) in pigs receiving SeMet- (0.44 mg Se/kg, above EU-legislated limits) or SeMix-supplemented (SeMet and NaSe both at 0.2 mg Se/kg, within EU-legislated limits) diets, which demonstrates Se metabolism upregulation to counteract the LPS-induced oxidative stress and a strengthened antioxidant capacity in these pigs. Overall, a Se source combination (without exceeding EU-legislated limits) and sufficient VitE supplementation (≥ 50 mg/kg) improved the pigs' antioxidant status, while doubling the allowed dietary organic Se increased the Se in tissues up to sixfold without compromising the animal's health due to toxicity. This study renders valuable results for revising the current dietary SeMet limits in swine rations.
Topics: Animals; Antioxidants; Dietary Supplements; Lipopolysaccharides; Selenium; Selenomethionine; Sodium Selenite; Swine; Vitamin E
PubMed: 36577830
DOI: 10.1007/s12011-022-03516-9 -
Journal of Dairy Science Oct 2023Streptococcus pyogenes is an important human pathogen, commonly spread by airborne droplets but also by ingestion of contaminated food. Apart from causing infection,...
Streptococcus pyogenes is an important human pathogen, commonly spread by airborne droplets but also by ingestion of contaminated food. Apart from causing infection, this pathogen produces 13 distinct types of streptococcal pyrogenic exotoxins (SPE). The current method for detection cannot distinguish between the biologically active form of SPE that has been reported to cause foodborne outbreaks and the inactivated toxin that poses no health risk. To measure the biological activity of SPE type C (SPE-C), one such toxin that was linked to foodborne outbreaks associated with milk and milk products, we developed a cell-based assay that can discern between biologically active and inactive SPE-C. To the best of our knowledge, this is the first showing that SPE-C activates T-cells expressing Vβ8. With this finding, we used a T-cell line natively expressing Vβ8 that was genetically engineered to also express the luciferase reporter gene under the regulation of nuclear factor of activated T-cells response element in combination with a B-cell line to present the recombinant SPE-C (rSPE-C) toxin via major histocompatibility complex (MHC) class II to the Vβ8 T-cell receptor (TCR) in an assay to detect and to discern between biologically active and inactive rSPE-C. By using this system, we demonstrated that SPE-C induced significant IL-2 secretion after 72 h and visible light emission after only 5 h, doubling by 24 h. We utilize this finding to assess the specificity of the assay and the effect of pasteurization on SPE-C activity. We observed no cross-reactivity with SPE-B and significant loss of SPE-C biological activity in spiked phosphate-buffered saline while SPE-C spiked into milk is heat stable. Once SPE-C has formed, it is infeasible to eliminate it from milk by thermal treatment.
Topics: Humans; Exotoxins; Bacterial Proteins; Streptococcus pyogenes; Histocompatibility Antigens Class II; Receptors, Antigen, T-Cell
PubMed: 37210361
DOI: 10.3168/jds.2023-23286 -
Veterinary Research Communications Dec 2023In this study, the efficiency of the ceftiofur N-acyl homoserine lactonase niosome against multi-resistant Klebsiella pneumoniae in broilers was evaluated. Fifty-six K....
In this study, the efficiency of the ceftiofur N-acyl homoserine lactonase niosome against multi-resistant Klebsiella pneumoniae in broilers was evaluated. Fifty-six K. pneumoniae isolates previously recovered from different poultry and environmental samples were screened for the ahlK gene. The lactonase enzyme was extracted from eight quorum-quenching isolates. The niosome was formulated, characterized, and tested for minimal inhibitory concentration (MIC) and cytotoxicity. Fourteen-day-old chicks were assigned to six groups: groups Ӏ and П served as negative and positive controls, receiving saline and K. pneumoniae solutions, respectively. In groups Ш and IV, ceftiofur and niosome were administrated intramuscularly at a dose of 10 mg/kg body weight for five consecutive days, while groups V and VI received the injections following the K. pneumoniae challenge. Signs, mortality, and gross lesions were recorded. Tracheal swabs were collected from groups П, V, and VI for counting K. pneumoniae. Pharmacokinetic parameters were evaluated in four treated groups at nine-time points. The niosome was spherical and 56.5 ± 4.41 nm in size. The viability of Vero cells was unaffected up to 5 × MIC (2.4 gml). The niosome-treated challenged group showed mild signs and lesions with lower mortality and colony count than the positive control group. The maximum ceftiofur serum concentrations in treated groups were observed 2 h following administration. The elimination half-life in niosome-treated groups was longer than that reported in ceftiofur-treated groups. This is the first report of the administration of N-acyl homoserine lactonase for the control of multi-resistant K. pneumoniae infections in poultry.
Topics: Chlorocebus aethiops; Animals; Klebsiella pneumoniae; Chickens; Liposomes; Vero Cells; Poultry; Anti-Bacterial Agents
PubMed: 37430152
DOI: 10.1007/s11259-023-10161-7 -
The Science of the Total Environment Dec 2023An integrated biological effects study using field transplanted mussels was applied to determine the potential biological effects of an effluent discharge from an...
An integrated biological effects study using field transplanted mussels was applied to determine the potential biological effects of an effluent discharge from an aluminium smelter into a Norwegian fjord. Chemical body burden and biological effects were measured in mussels positioned downstream (1, 2, 5, 10 and 20 km) from the aluminium smelters discharge for a period of 6 weeks. A suite of biomarkers, from whole organism to subcellular responses were measured. Chemical concentrations in mussel tissues were low; however, a change in the PAC (polyaromatic compound) profile from high to low pyrogenic influence provided evidence of exposure to the smelter's effluent. Overall, the biological responses observed where greater in the mussels positioned closest to the smelter (1-5 km). Lowest chemical accumulation and biomarker responses were observed in mussels positioned 10 km from the smelter and were considered as the reference field population. Mussels located furthest from the smelter (20 km) exhibited significant biomarker responses and suggested a different contaminant source within the fjord. The integrated biological response index (IBR) was applied and reflected the expected level of exposure to the smelters discharge, with highest IBR calculated in mussels positioned closest to the discharge (1-5 km). Principal component analysis (PCA) also differentiated among mussel groups, with the most impacted located closest to the smelter. Not one chemical factor could explain the biological responses observed in mussels, but the presence of PAH16, PAH41 and metals Mn, Ni and Cr were the main contributors measured to the higher stress seen in the mussels from the 1 and 5 km groups.
Topics: Animals; Water; Aluminum; Water Pollutants, Chemical; Environmental Monitoring; Bivalvia; Biomarkers
PubMed: 37673263
DOI: 10.1016/j.scitotenv.2023.166798 -
3D Printing in Medicine Feb 2024Low temperature vaporized hydrogen peroxide sterilization (VH2O2) is used in hospitals today to sterilize reusable medical devices. VH2O2 sterilized 3D printed materials...
BACKGROUND
Low temperature vaporized hydrogen peroxide sterilization (VH2O2) is used in hospitals today to sterilize reusable medical devices. VH2O2 sterilized 3D printed materials were evaluated for sterilization, biocompatibility and material compatibility.
MATERIALS & METHODS
Test articles were printed at Formlabs with BioMed Clear™ and BioMed Amber™, and at Stratasys with MED610™, MED615™ and MED620™. Sterilization, biocompatibility and material compatibility studies with 3D printed materials were conducted after VH2O2 sterilization in V-PRO™ Sterilizers. The overkill method was used to evaluate sterilization in a ½ cycle. Biocompatibility testing evaluated the processed materials as limited contact (< 24-hours) surface or externally communicating devices. Material compatibility after VH2O2 sterilization (material strength and dimensionality) was evaluated via ASTM methods and dimensional analysis.
RESULTS
3D printed devices, within a specific design window, were sterile after VH2O2 ½ cycles. After multiple cycle exposure, the materials were not cytotoxic, not sensitizing, not an irritant, not a systemic toxin, not pyrogenic and were hemo-compatible. Material compatibility via ASTM testing and dimensionality evaluations did not indicate any significant changes to the 3D printed materials after VH2O2 sterilization.
CONCLUSION
Low temperature vaporized hydrogen peroxide sterilization is demonstrated as a suitable method to sterilize 3D printed devices. The results are a subset of the data used in a regulatory submission with the US FDA to support claims for sterilization of 3D printed devices with specified materials, printers, and device design .
PubMed: 38416324
DOI: 10.1186/s41205-024-00206-1