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1.
Int J Clin Pharmacol Ther ; 62(5): 213-221, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38431832

RESUMO

OBJECTIVE: Irinotecan (IRI) is an anticancer drug that is frequently used to treat colorectal, gastric, and pancreatic cancers. Its side effects include cholinergic symptoms, such as diarrhea, abdominal pain, nausea, and hyperhidrosis. Anticholinergic medicines are frequently used for treatment or prophylaxis; however, the risk factors for the failure of a single prophylactic anticholinergic administration remain unclear. Moreover, an appropriate anticholinergic drug for prophylaxis remains unknown. Thus, we aimed to identify the risk factors associated with the failure of a single prophylactic dose of anticholinergic drugs for IRI-induced cholinergic symptoms and to evaluate the usefulness of multiple prophylactic doses of anticholinergic drugs. MATERIALS AND METHODS: Patients who underwent IRI treatment for colorectal, gastric, or pancreatic cancer and received prophylactic anticholinergic drugs for IRI-induced cholinergic symptoms (n = 135) were retrospectively evaluated. Univariate and multivariate logistic regression analyses were performed to identify the risk factors for failure of a single prophylactic dose of anticholinergic drugs. We also evaluated the efficacy of multiple prophylactic anticholinergic drug administration. RESULTS: Based on univariate and multivariate analyses, colorectal cancer, female sex, and prophylactic use of scopolamine butyl bromide were identified as risk factors for failure of a single prophylactic dose of anticholinergic drugs. The efficacy of multiple prophylactic doses was confirmed to be 95% of the patients who had a single prophylactic failure due to temporary effect but symptom appearance after a certain period of time (wearing-off). CONCLUSION: We determined that colorectal cancer, female sex, and prophylactic use of scopolamine butyl bromide were risk factors associated with the failure of a single prophylactic dose of anticholinergic drugs, and that multiple prophylactic doses for wearing-off can be a promising method.


Assuntos
Antagonistas Colinérgicos , Neoplasias Colorretais , Hidrocarbonetos Bromados , Humanos , Feminino , Irinotecano/efeitos adversos , Estudos Retrospectivos , Antagonistas Colinérgicos/efeitos adversos , Fatores de Risco , Colinérgicos , Brometo de Butilescopolamônio , Neoplasias Colorretais/tratamento farmacológico
2.
J Mater Chem B ; 12(15): 3764-3773, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38533806

RESUMO

In this study, we utilized X-ray-induced photodynamic therapy (X-PDT) against triple-negative breast cancer (TNBC) cells. To achieve this, we developed a liposome delivery system that co-loaded protoporphyrin IX (PPIX) and perfluorooctyl bromide (PFOB) in a rational manner. Low-dose X-ray at 2 Gy was employed to activate PPIX for the generation of reactive oxygen species (ROS), and the co-loading of PFOB provided additional oxygen to enhance ROS production. The resulting highly toxic ROS effectively induced cell death in TNBC. In vitro X-PDT effects, including intracellular ROS generation, cell viability, and apoptosis/necrosis assays in TNBC cells, were thoroughly investigated. Our results indicate that the nanocarriers effectively induced X-PDT effects with very low-dose radiation, making it feasible to damage cancer cells. This suggests the potential for the effective utilization of X-PDT in treating hypoxic cancers, including TNBC, with only a fraction of conventional radiotherapy.


Assuntos
Fluorocarbonos , Hidrocarbonetos Bromados , Fotoquimioterapia , Protoporfirinas , Neoplasias de Mama Triplo Negativas , Humanos , Fotoquimioterapia/métodos , Lipossomos/uso terapêutico , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Espécies Reativas de Oxigênio/metabolismo
3.
PLoS Med ; 21(3): e1004352, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38547322

RESUMO

BACKGROUND: Prolonged labor is a common condition associated with maternal and perinatal complications. The standard treatment with oxytocin for augmentation of labor increases the risk of adverse outcomes. Hyoscine butylbromide is a spasmolytic drug with few side effects shown to shorten labor when used in a general population of laboring women. However, research on its effect on preventing prolonged labor is lacking. We aimed to assess the effect of hyoscine butylbromide on the duration of labor in nulliparous women showing early signs of slow labor. METHODS AND FINDINGS: In this double-blind randomized placebo-controlled trial, we included 249 nulliparous women at term with 1 fetus in cephalic presentation and spontaneous start of labor, showing early signs of prolonged labor by crossing the alert line of the World Health Organization (WHO) partograph. The trial was conducted at Oslo University Hospital in Norway from May 2019 to December 2021. One hundred and twenty-five participants were randomized to receive 1 ml hyoscine butylbromide (Buscopan) (20 mg/ml), while 124 received 1 ml sodium chloride intravenously. Randomization was computer-generated, with allocation concealment by opaque sequentially numbered sealed envelopes. The primary outcome was duration of labor from administration of the investigational medicinal product (IMP) to vaginal delivery, which was analyzed by Weibull regression to estimate the cause-specific hazard ratio (HR) of vaginal delivery between the 2 treatment groups, with associated 95% confidence interval (CI). A wide range of secondary maternal and perinatal outcomes were also evaluated. Time-to-event outcomes were analyzed by Weibull regression, whereas continuous and dichotomous outcomes were analyzed by median regression and logistic regression, respectively. All main analyses were based on the modified intention-to-treat (ITT) set of eligible women with signed informed consent receiving either of the 2 treatments. The follow-up period lasted during the postpartum hospital stay. All personnel, participants, and researchers were blinded to the treatment allocation. Median (mean) labor duration from IMP administration to vaginal delivery was 401 (440.8) min in the hyoscine butylbromide group versus 432.5 (453.6) min in the placebo group. We found no statistically significant association between IMP and duration of labor from IMP administration to vaginal delivery: cause-specific HR of 1.00 (95% CI [0.77, 1.29]; p = 0.993). Among 255 randomized women having received 1 dose of IMP, 169 women (66.3%) reported a mild adverse event: 75.2% in the hyoscine butylbromide group and 57.1% in the placebo group (Pearson's chi-square test: p = 0.002). More than half of eligible women were not included in the study because they did not wish to participate or were not included upon admission. The participants might have represented a selected group of women reducing the external validity of the study. CONCLUSIONS: One intravenous dose of 20 mg hyoscine butylbromide was not found to be superior to placebo in preventing slow labor progress in a population of first-time mothers at risk of prolonged labor. Further research is warranted to answer whether increased and/or repeated doses of hyoscine butylbromide might have an effect on duration of labor. TRIAL REGISTRATION: ClinicalTrials.gov (NCT03961165) EudraCT (2018-002338-19).


Assuntos
Brometo de Butilescopolamônio , Hidrocarbonetos Bromados , Trabalho de Parto , Gravidez , Humanos , Feminino , Brometo de Butilescopolamônio/efeitos adversos , Escopolamina , Parassimpatolíticos/uso terapêutico , Método Duplo-Cego
4.
Sci Rep ; 14(1): 6486, 2024 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-38499858

RESUMO

Brominated flame retardants (BFRs) are a group of chemicals widely used in various applications to prevent or slow down the spread of fire. However, they have adverse effects on human health. There is a relative scarcity of population-based studies regarding BFRs, particularly their impact on the respiratory system. This study aimed to investigate the influence of BFRs on pulmonary function using data from the National Health and Nutrition Examination Survey. The study found that elevated serum concentrations of certain BFRs were associated with pulmonary ventilatory dysfunction. Adjusted analyses revealed positive correlations between PBDE47, PBDE183, and PBDE209 concentrations and ventilatory dysfunction. The analysis of mixed BFRs showed a positive relationship with pulmonary ventilation dysfunction, with PBDE47 making the most significant contribution. Our study demonstrates that both individual and combined BFRs exposure can lead to impaired pulmonary ventilation function. These findings provide evidence of the adverse effects of BFRs on lung function, emphasizing the importance of further investigating the potential health consequences of these compounds. Further large-scale longitudinal studies are needed to investigate this relationship in the future.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Retardadores de Chama , Hidrocarbonetos Bromados , Adulto , Humanos , Hidrocarbonetos Bromados/efeitos adversos , Retardadores de Chama/efeitos adversos , Retardadores de Chama/análise , Estudos Transversais , Inquéritos Nutricionais , Éteres Difenil Halogenados/análise , Pulmão/química
5.
J Hazard Mater ; 469: 134036, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38493623

RESUMO

1,2,5,6,9,10-Hexabromocyclododecanes (HBCDs) are a sort of persistent organic pollutants (POPs). This research investigated 12 microbial communities enriched from sediments of four mangroves in China to transform HBCDs. Six microbial communities gained high transformation rates (27.5-97.7%) after 12 generations of serial transfer. Bacteria were the main contributors to transform HBCDs rather than fungi. Analyses on the bacterial compositions and binning genomes showed that Alcanivorax (55.246-84.942%) harboring haloalkane dehalogenase genes dadAH and dadBH dominated the microbial communities with high transformation rates. Moreover, expressions of dadAH and dadBH in the microbial communities and Alcanivorax isolate could be induced by HBCDs. Further, it was found that purified proteins DadAH and DadBH showed high conversion rates on HBCDs in 36 h (91.9 ± 7.4 and 101.0 ± 1.8%, respectively). The engineered Escherichia coli BL21 strains harbored two genes could convert 5.7 ± 0.4 and 35.1 ± 0.1% HBCDs, respectively, lower than their cell-free crude extracts (61.2 ± 5.2 and 56.5 ± 8.7%, respectively). The diastereoisomer-specific transforming trend by both microbial communities and enzymes were γ- > α- > ß-HBCD, differed from α- > ß- > Î³-HBCD by the Alcanivorax isolate. The identified transformation products indicated that HBCDs were dehalogenated via HBr elimination (dehydrobromination), hydrolytic and reductive debromination pathways in the enriched cultures. Two enzymes converted HBCDs via hydrolytic debromination. The present research provided theoretical bases for the biotransformation of HBCDs by microbial community and the bioremediation of HBCDs contamination in the environment.


Assuntos
Retardadores de Chama , Hidrocarbonetos Bromados , Microbiota , Estereoisomerismo , Hidrocarbonetos Bromados/metabolismo , Biotransformação , Bactérias/metabolismo
6.
Aquat Toxicol ; 268: 106853, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38330652

RESUMO

Hexabromocyclododecane (HBCD), third-generation brominated flame retardants (BRFs), has aroused worldwide concern because of its wide application and potentially negative impacts on marine ecosystems, but an information gap still exists regarding marine low-trophic organisms. Brachionus plicatilis, the model marine zooplankton, was used in the present study, and its reproductive responses were used as the endpoint to indicate HBCD-induced toxicity. HBCD was suggested to be extremely highly toxic compounds regarding the 96 h-LC50 of 0.58 mg L-1. The sublethal exposure of HBCD injured the reproduction of B. plicatilis: The total number of offspring per female and the key population index calculated from the life table, including the intrinsic rate of population increase (rm) and net reproductive rate (R0), were significantly influenced in a concentration-dependent manner. The reproductive process was also altered, as indicated by the first spawning time, first hatching time and oocyst development time. At the same time, individual survival and growth (body length) were also negatively affected by HBCD. Reactive oxygen species (ROS) were suggested to be responsible for reproductive toxicity mainly because the total ROS contents as well as the main components of •OH and H2O2 greatly increased and resulted in the oxidative imbalance that presented as malondialdehyde (MDA) elevation. Simultaneous activation of the glutathione antioxidant system was accompanied by the apoptosis marker enzymes Caspase-3 and 9, as well as the correlation between ROS content, physiological alteration and cell apoptosis, providing further evidence for this. The integrated biomarker response (IBR) and adverse outcome pathway (AOP) showed that HBCD had a significant toxic effect on B. plicatilis near the concentration range of 96 h-LC50. The establishment of this concentration range will provide a reliable reference for future environmental concentration warning of HBCD in marine.


Assuntos
Retardadores de Chama , Hidrocarbonetos Bromados , Rotíferos , Poluentes Químicos da Água , Animais , Feminino , Espécies Reativas de Oxigênio/metabolismo , Ecossistema , Peróxido de Hidrogênio , Poluentes Químicos da Água/toxicidade , Hidrocarbonetos Bromados/toxicidade , Reprodução , Retardadores de Chama/toxicidade
7.
Environ Sci Technol ; 58(9): 4237-4246, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38386008

RESUMO

Concentrations of polybrominated diphenyl ethers, hexabromocyclododecane (HBCDD), and novel brominated flame retardants (NBFRs) were measured in indoor dust, indoor air, and outdoor air in Birmingham, UK. Concentrations of ΣBFRs ranged from 490 to 89,000 ng/g, 46-14,000 pg/m3, and 22-11,000 pg/m3, respectively, in UK indoor dust, indoor air, and outdoor air. BDE-209 and decabromodiphenyl ethane (DBDPE) were the main contributors. The maximum concentration of DBDPE (10,000 pg/m3) in outdoor air is the highest reported anywhere to date. In contrast with previous studies of outdoor air in Birmingham, we observed significant correlations between concentrations of tri- to hepta-BDEs and HBCDD and temperature. This may suggest that primary emissions from ongoing use of these BFRs have diminished and that secondary emissions (e.g., evaporation from soil) are now a potentially major source of these BFRs in outdoor air. Conversely, the lack of significant correlations between temperature and concentrations of BDE-209 and DBDPE may indicate that ongoing primary emissions from indoor sources remain important for these BFRs. Further research to clarify the relative importance of primary and secondary sources of BFRs to outdoor air is required. Comparison with earlier studies in Birmingham reveals significant (p < 0.05) declines in concentrations of legacy BFRs, but significant increases for NBFRs over the past decade. While there appear minimal health burdens from BFR exposure for UK adults, dust ingestion of BDE-209 may pose a significant risk for UK toddlers.


Assuntos
Poluição do Ar em Ambientes Fechados , Retardadores de Chama , Hidrocarbonetos Bromados , Adulto , Humanos , Poluição do Ar em Ambientes Fechados/análise , Poeira/análise , Monitoramento Ambiental , Retardadores de Chama/análise , Éteres Difenil Halogenados/análise , Reino Unido , Bromo/análise
8.
Environ Pollut ; 346: 123645, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38402939

RESUMO

Brominated flame retardants (BFRs) are bromine-bearing additives added to the polymeric fraction in various applications to impede fire ignition. The Stockholm Convention and various other legislations abolished legacy BFRs usage and hence, the so-called novel BFRs (NBFRs) were introduced into the market. Recent studies spotlighted their existence in household dust, aquifers and aquatic/aerial species. Co-pyrolysis of BFRs with metal oxides has emerged as a potent chemical recycling approach that produces a bromine-free stream of hydrocarbon. Herein, we investigate the debromination of two prominent two NBFRs; namely tetrabromobisphenol A 2,3-dibromopropyl ether (TD) and tetrabromobisphenol A diallyl ether (TAE) through their co-pyrolysis with zinc oxide (ZnO) and franklinite (ZnFe2O4). Most of the zinc content in electrical arc furnace dust (EAFD) exists in the form of these two metal oxides. Conversion of these metal oxides into their respective bromides could also assist in the selective extraction of the valuable zinc content in EAFD. The debromination potential of both oxides was unveiled via a multitude of characterization studies to analyze products (char, gas and condensates). The thermogravimetric analysis suggested a pyrolytic run up to 500 °C and the TAE treatment with ZnO produced only a trivial amount of brominated compounds (relative area, 0.83%). Phenol was the sole common compound in condensable products; potentially formed by the ß-scission debromination reaction from the parental molecular skeleton. Inorganic compounds and methane were the major constituents in the gaseous products. The pyrochar analyses confirmed the presence of metal bromides retained in the residue, averting the bromine release into the atmosphere. The ion chromatography analysis portrayed <8% of HBr gas release into the atmosphere upon pyrolysis with ZnO. The ZnO dominance herein envisaged further probes into other spinel ferrites in combating brominated polymers.


Assuntos
Resíduo Eletrônico , Retardadores de Chama , Hidrocarbonetos Bromados , Bifenil Polibromatos , Óxido de Zinco , Retardadores de Chama/análise , Resíduo Eletrônico/análise , Bromo , Brometos , Reciclagem/métodos , Polímeros , Zinco/análise , Poeira , Éteres , Hidrocarbonetos Bromados/análise
9.
Environ Sci Technol ; 58(9): 4127-4136, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38382014

RESUMO

Tetrabromobisphenol A-bis(2,3-dibromo-2-methylpropyl ether) (TBBPA-DBMPE) has come into use as an alternative to hexabromocyclododecane (HBCD), but it is unclear whether TBBPA-DBMPE has less hazard than HBCD. Here, we compared the bioaccumulation and male reproductive toxicity between TBBPA-DBMPE and HBCD in mice following long-term oral exposure after birth. We found that the concentrations of TBBPA-DBMPE in livers significantly increased with time, exhibiting a bioaccumulation potency not substantially different from HBCD. Lactational exposure to 1000 µg/kg/d TBBPA-DBMPE as well as 50 µg/kg/d HBCD inhibited testis development in suckling pups, and extended exposure up to adulthood resulted in significant molecular and cellular alterations in testes, with slighter effects of 50 µg/kg/d TBBPA-DBMPE. When exposure was extended to 8 month age, severe reproductive impairments including reduced sperm count, increased abnormal sperm, and subfertility occurred in all treated animals, although 50 µg/kg/d TBBPA-DBMPE exerted lower effects than 50 µg/kg/d HBCD. Altogether, all data led us to conclude that TBBPA-DBMPE exerted weaker male reproductive toxicity than HBCD at the same doses but exhibited bioaccumulation potential roughly equivalent to HBCD. Our study fills the data gap regarding the bioaccumulation and toxicity of TBBPA-DBMPE and raises concerns about its use as an alternative to HBCD.


Assuntos
Retardadores de Chama , Hidrocarbonetos Bromados , Bifenil Polibromatos , Masculino , Animais , Camundongos , Retardadores de Chama/toxicidade , Éter , Bioacumulação , Sêmen , Hidrocarbonetos Bromados/toxicidade , Bifenil Polibromatos/toxicidade , Éteres , Etil-Éteres
10.
Toxicol Lett ; 394: 11-22, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38387762

RESUMO

BACKGROUND: The incidence of endocrine-related cancer, which includes tumors in major endocrine glands such as the breast, thyroid, pituitary, and prostate, has been increasing year by year. Various studies have indicated that brominated flame retardants (BFRs) are neurotoxic, endocrine-toxic, reproductive-toxic, and even carcinogenic. However, the epidemiological relationship between BFR exposure and endocrine-related cancer risk remains unclear. METHODS: We searched the PubMed, Google Scholar, and Web of Science databases for articles evaluating the association between BFR exposure and endocrine-related cancer risk. The odds ratio (OR) and its corresponding 95% confidence interval (95% CI) were used to assess the association. Statistical heterogeneity among studies was assessed with the Q-test and I2 statistics. Begg's test was performed to evaluate the publication bias. RESULTS: We collected 15 studies, including 6 nested case-control and 9 case-control studies, with 3468 cases and 4187 controls. These studies assessed the risk of breast cancer, thyroid cancer, and endocrine-related cancers in relation to BFR levels. Our findings indicate a significant association between BFR exposure in adipose tissue and an increased risk of breast cancer. However, this association was not observed for thyroid cancer. Generally, BFR exposure appears to elevate the risk of endocrine-related cancers, with a notable increase in risk linked to higher levels of BDE-28, a specific polybrominated diphenyl ether congener. CONCLUSIONS: In conclusion, although this meta-analysis has several limitations, our results suggest that BFR exposure is a significant risk factor for breast cancer, and low-brominated BDE-28 exposure could significantly increase the risk of endocrine-related cancers. Further research is essential to clarify the potential causal relationships between BFRs and endocrine-related cancers, and their carcinogenic mechanisms.


Assuntos
Neoplasias da Mama , Retardadores de Chama , Hidrocarbonetos Bromados , Bifenil Polibromatos , Masculino , Humanos , Retardadores de Chama/toxicidade , Éteres Difenil Halogenados/toxicidade , Fatores de Risco , Hidrocarbonetos Bromados/toxicidade
11.
Int J Mol Sci ; 25(2)2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38255957

RESUMO

In this work, we present the effect of graphene nanoplatelets (GnPs) modification with ionic liquids (ILs). The textural properties of graphene nanoplatelets (GnPs) used as styrene-butadiene rubber's filler and the thermal properties of the composites obtained with the use of the mentioned fillers were investigated. GnPs were modified with 1-butylpyridinium bromide (BPyBr) and 4-methyl-1-butylpyridinium bromide (BmPyBr) through two different ways. One strategy has been to deposit the filler modifier from the solution. The second one involved the modification of the filler with ionic liquids in bulk during the preparation of elastomer blends. Settlement of the proposed ionic liquids onto the GnPs' surface led to significant changes in the textural characteristics. BPyBr has restricted the filler's microporosity, whereas BmPyBr has caused the formation of a more opened filler structure without the increase in its average pore size. GnPs modified with ILs led to reducing the temperature of vulcanization of SBR compounds and affected the thermal stability of the composites.


Assuntos
Grafite , Hidrocarbonetos Bromados , Líquidos Iônicos , Brometos , Elastômeros , Excipientes
12.
Environ Int ; 183: 108409, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38185044

RESUMO

Persistent pollutants, namely brominated flame retardants (BFRs) and heavy metals, are compounds that are added to a wide range of products and materials for preventing ignition, increasing the functionality of materials or improving their performance, e.g. electric conductivity. The exposure of children might consequently be inferred, through indoor dust and hand-to-mouth or toy-chewing behaviors. The current study is aimed at assessing the exposure of Moroccan children to BFRs and heavy metal elements, and evaluating their associations with global DNA methylation. First, parents responded to a questionnaire pertaining to children's lifestyle, then blood and urine samples were collected from (n = 93) children aged between 5 and 11 years for biomonitoring and DNA methylation analysis. BFRs were detected in 54.84% of samples with a median concentration of 0.01 nmol/mL (range: 0.004-0.051 nmol/mL) while metal elements were detected in more than 90% of samples. BFRs showed no variations with global DNA methylation, unlike metal elements, which revealed significant associations with global DNA methylation markers, namely 5-mC, 5-hmC and N6-mA levels. Moroccan children may be exposed to flame retardants and heavy metals through several routes. Further research is required to assess the exposure and the health impacts of environmental pollutants and ultimately protect the Moroccan population by the prevention of adverse health effects.


Assuntos
Poluição do Ar em Ambientes Fechados , Poluentes Ambientais , Retardadores de Chama , Hidrocarbonetos Bromados , Metais Pesados , Criança , Humanos , Pré-Escolar , Retardadores de Chama/análise , Marrocos , Poluição do Ar em Ambientes Fechados/análise , Éteres Difenil Halogenados/análise , Poluentes Ambientais/análise , Poeira/análise , Metais Pesados/análise , Adenina/análise , Monitoramento Ambiental , Exposição Ambiental/análise , Hidrocarbonetos Bromados/análise
13.
J Mater Chem B ; 12(4): 991-1000, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38193597

RESUMO

Hair dermal papilla cells (hDPCs) play a crucial role in hair growth and regeneration, and their function is influenced by nutrient and oxygen supply. A microenvironment with significantly low oxygen (O2) levels, known as anoxic conditions (<0.2%) due to oxygen deficiency, hinders hDPC promotion and retards hair regrowth. Here, a nanoemulsion (NE) based on perfluorooctyl bromide (PFOB), a member of the perfluorocarbon family, is presented to provide a sustainable O2 supply and maintain physical stability in vitro. The PFOB-NE has been shown to continuously release oxygen for 36 h, increasing and maintaining the O2 concentration in the anoxic microenvironment of up to 0.8%. This sustainable O2 supply using PFOB-NE has promoted hDPC growth and also induced a complex cascade of effects. These effects encompass regulation via inhibiting lactate accumulation caused via oxygen deficiency, increasing lactate dehydrogenase activity, and promoting the expression of genes, such as the hypoxia-inducible factor 1 family and NADPH oxidase 4 under anoxic conditions. Sustained O2 supply is shown to enhance human hair organ elongation approximately four times compared to the control under anoxic conditions. In conclusion, the perfluorocarbon-based NE containing oxygen proves to be an important strategic tool for improving hair growth and alleviating hair loss.


Assuntos
Fluorocarbonos , Hidrocarbonetos Bromados , Hipóxia , Humanos , Oxigênio/metabolismo , Fluorocarbonos/farmacologia , Cabelo
14.
Braz Oral Res ; 38: e001, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38198301

RESUMO

The aim of this study was to evaluate the influence of adding quaternary ammonium methacrylates (QAMs) to experimental adhesives by assessing the degree of conversion (DC), cytotoxicity against keratinocytes and fibroblasts, and antibacterial activity against biofilm formation. Two QAMs were added to an experimental adhesive: dimethylaminododecyl methacrylate bromododecane (DMADDM) or dimethylaminododecyl methacrylate bromohexadecane (DMAHDM) at three concentrations each: 1, 2.5, and 5 wt.%. Experimental adhesive without QAMs (control group) and commercially available Transbond XT Primer (3M Unitek, Monrovia, California, USA) were used for comparisons. The adhesives were tested for DC, cytotoxicity against keratinocytes and fibroblasts, and antibacterial activity against biofilm formation. DC, cytotoxicity against fibroblasts, and antibacterial activity were analyzed using one-way ANOVA and Tukey's multiple comparisons. Cytotoxicity against keratinocytes was evaluated using the Kruskal Wallis and Dunn's post-hoc (α = 5%) tests. Transbond showed lower DC as compared to 5% DMAHDM, 1% DMADDM, and 5% DMADDM (p < 0.05). However, all groups presented proper DC when compared to commercial adhesives in the literature. In the evaluation of cytotoxicity against keratinocytes, Transbond induced higher viability than 2.5 wt.% groups (p < 0.05). Against fibroblasts, Transbond induced higher viability as compared to 5 wt.% groups (p < 0.05). DMAHDM at 5 wt.% reduced biofilm formation when compared to all the other groups (p < 0.05). Despite their cytotoxic effect against keratinocytes, gingival fibroblasts showed higher viability. DMAHDM at 5 wt.% decreased Streptococcus mutans viability. The incorporation of DMAHDM at 5 wt.% may be a strategy for reducing the development of white spot lesions.


Assuntos
Antibacterianos , Bis-Fenol A-Glicidil Metacrilato , Hidrocarbonetos Bromados , Metacrilatos , Metilaminas , Compostos de Amônio Quaternário , Metacrilatos/farmacologia , Antibacterianos/farmacologia
15.
Mar Environ Res ; 194: 106314, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38185000

RESUMO

Pollutants in the ecological environment of fishery seawater are harmful to the survival and reproduction of aquatic organisms. Hexabromocyclododecanes (HBCDs) were 42.9% detected within ND-48.89 ng/L in 177 seawater samples and 30.7% within ND-1.07 ng/g dw in 88 sediment samples of the fisheries in the Yellow Sea and East China Sea, respectively. γ-HBCD accounted for 65% of seawater and 89% of sediment samples. HBCDs in seawater in winter (ND-48.89 ng/L) were significantly higher than in summer (ND-4.99 ng/L), possibly because the re-suspension caused by winds and waves could re-migrate HBCDs from the sediment to the seawater in winter. However, seasonal differences of HBCDs in sediment were not significant. The fugacities indicated HBCDs' migrating trend from seawater to sediment due to their hydrophobic nature. There is almost no terrestrial input of HBCDs from the Yangtze and Yellow Rivers, and currently used fishery materials in marine may compose long-lasting sources of HBCDs.


Assuntos
Monitoramento Ambiental , Hidrocarbonetos Bromados , Poluentes Químicos da Água , Estações do Ano , Sedimentos Geológicos/química , Poluentes Químicos da Água/análise , Caça , Água do Mar , China
16.
Environ Pollut ; 341: 122895, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37949162

RESUMO

The brominated flame retardant tetrabromobisphenol A-bis(2,3-dibromo-2-methylpropyl ether) (TBBPA-DBMPE) is a recommended substitute for hexabromocyclododecane (HBCD), a banned persistent organic pollutant, yet its potential toxicities remains largely unexplored. Here, we investigated the effects of a long-term exposure to TBBPA-DBMPE at nominal doses of 50 and 1000 µg/kg/d on lipid homeostasis in CD-1 mice, in comparison with 50 µg/kg/d HBCD as a positive control. Male pups received chemical treatments through maternal administration via drinking water from postnatal day 0-21, followed by direct administration through drinking water after weaning. On the 23rd week after treatment, the oral lipid tolerance test revealed that low-dose TBBPA-DBMPE as well as HBCD affected lipid tolerance, although the fasting serum triglyceride (TG) levels were not altered. When chemical treatment was extended to the 32nd week, TBBPA-DBMPE-treated animals displayed adipocyte hypertrophy in both white adipose tissue (eWAT) and brown adipose tissue (BAT) and hepatic steatosis, which was largely consistent with the effects of HBCD. These findings indicate that like HBCD, TBBPA-DBMPE led to increased lipid load in mice. Interestingly, we also observed intestinal histological changes, coupled with increased expression of lipid absorption-related genes in both HBCD and TBBPA-DBMPE treatments, suggesting increased lipid absorption. This was supported by in vitro findings that both HBCD and TBBPA-DBMPE promoted lipid accumulation in IEC-6 cells under the stress of oleic acid for 6 h, implying that altered lipid absorption by the intestine may partly contributed to increased lipid load in mice. Overall, the effects of 50 µg/kg/d TBBPA-DBMPE in terms of some parameters were comparable with 50 µg/kg/d HBCD, suggesting that TBBPA-DBMPE may not be an ideal substitute of HBCD.


Assuntos
Água Potável , Retardadores de Chama , Hidrocarbonetos Bromados , Bifenil Polibromatos , Masculino , Camundongos , Animais , Retardadores de Chama/toxicidade , Retardadores de Chama/análise , Éter , Hidrocarbonetos Bromados/toxicidade , Hidrocarbonetos Bromados/análise , Bifenil Polibromatos/toxicidade , Bifenil Polibromatos/análise , Éteres , Etil-Éteres , Lipídeos
17.
J Environ Qual ; 53(1): 47-56, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37939688

RESUMO

Methyl bromide (MeBr) is a sterilizing fumigant used to control quarantine pests that is restricted due to its detrimental atmospheric effects. The degradation of injected MeBr produces crop-available Br- . Up to five applications of MeBr were used in southeastern Idaho fields to combat the pale cyst nematode (Globodera pallida). Data regarding the uptake and partitioning of Br- in crops following MeBr application in the region were unavailable. Research determined background concentrations of Br- in alfalfa (Medicago sativa L.), barley (Hordeum vulgare L.), corn (Zea mays L.), potato (Solanum tuberosum L.), and wheat (Triticum aestivum L.) compared to MeBr-treated fields. Background Br- concentrations ranged from nondetectable (ND) to 33.0 mg Br- kg-1 ; vegetative tissue concentrations were greater than reproductive, except corn where there was no difference. Nearly all crops grown in MeBr-treated fields had greater Br- concentrations than background. Background-baled-alfalfa tissue Br- concentration was 33.0 mg kg-1 compared to 117.8 mg Br- kg-1 from a MeBr-treated field. Br- concentration in green alfalfa decreased from 79.8 to 36.5 mg Br- kg-1 at the final cutting in a MeBr-treated field, where time after application decreased crop Br- concentrations. Small grains had low Br- concentrations in reproductive tissue (1.7 mg Br- kg-1 ) compared to vegetative tissue (106.5 mg Br- kg-1 ). Corn stover concentration (12.7 mg Br- kg-1 ) was low relative to small-grain straw, but corn ear (5.8 mg Br- kg-1 ) was greater than small-grain reproductive tissue in the MeBr-treated field. Crop selection following MeBr applications should consider the likelihood of elevated Br- concentration for the plant fractions intended end use.


Assuntos
Brometos , Hidrocarbonetos Bromados , Nematoides , Animais , Fumigação , Idaho
18.
Environ Toxicol Pharmacol ; 105: 104343, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38122861

RESUMO

Assessing the role of α-hexabromocyclododecane α-HBCDD as a factor of susceptibility for Autism Spectrum disorders by using valproic acid-exposed rat model (VPA) required characterizing VPA pharmacokinetic in the context of α-HBCDD-co-exposure in non-pregnant and pregnant rats. The animals were exposed to α-HBCDD by gavage (100 ng/kg/day) for 12 days. This was followed by a single intraperitoneal dose of VPA (500 mg/kg) or a daily oral dose of VPA (500 mg/kg) for 3 days. Exposure to α-HBCDD did not affect the pharmacokinetics of VPA in pregnant or non-pregnant rats. Surprisingly, VPA administration altered the pharmacokinetics of α-HBCDD. VPA also triggered higher foetal toxicity and lethality with the PO than IP route. α-HBCDD did not aggravate the embryotoxicity observed with VPA, regardless of the route of exposure. Based on this evidence, a single administration of 500 mg/kg IP is the most suitable VPA model to investigate α-HBCDD co-exposure.


Assuntos
Transtorno do Espectro Autista , Hidrocarbonetos Bromados , Efeitos Tardios da Exposição Pré-Natal , Gravidez , Humanos , Feminino , Ratos , Animais , Ácido Valproico/toxicidade , Transtorno do Espectro Autista/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Hidrocarbonetos Bromados/toxicidade , Modelos Animais de Doenças
19.
NMR Biomed ; 37(4): e5086, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38110293

RESUMO

Fluorine MRI is finding wider acceptance in theranostics applications where imaging of 19 F hotspots of fluorinated contrast material is central. The essence of such applications is to capture ghosting-artifact-free images of the inherently low MR response under clinically viable conditions. To serve this purpose, this work introduces the balanced spiral spectroscopic imaging (BaSSI) sequence, which is implemented on a 3.0 T clinical scanner and is capable of generating 19 F hotspot images in an efficient manner. The sequence utilizes an all-phase-encoded pseudo-spiral k-space trajectory, enabling the acquisition of broadband (80 ppm) fluorine spectra free from chemical shift ghosting. BaSSI can acquire a 64 × 64 image with 1 mm × 1 mm voxels in just 14 s, significantly outperforming typical MRSI sequences used in 1 H or 31 P imaging. The study employed in silico characterization to verify essential design choices such as the excitation pulse, as well as to identify the boundaries of the parameter space explored for optimization. BaSSI's performance was further benchmarked against the 3D ultrashort-echo-time balanced steady-state free precession (3D UTE BSSFP) sequence, a well established method used in 19 F MRI, in vitro. Both sequences underwent extensive optimization through exploration of a wide parameter space on a small phantom containing 10 µL of non-diluted bulk perfluorooctylbromide (PFOB) prior to comparative experiments. Subsequent to optimization, BaSSI and 3D UTE BSSFP were employed to capture images of small non-diluted bulk PFOB samples (0.10 and 0.05 µL), with variations in the number of signal averages, and thus the total scan time, in order to assess the detection sensitivities of the sequences. In these experiments, the detection sensitivity was evaluated using the Rose criterion (Rc ), which provides a quantitative metric for assessing object visibility. The study further demonstrated BaSSI's utility as a (pre)clinical tool through postmortem imaging of polymer microspheres filled with PFOB in a BALB/c mouse. Anatomic localization of 19 F hotspots was achieved by denoising raw data obtained with BaSSI using a filter based on the Rose criterion. These data were then successfully registered to 1 H anatomical images. BaSSI demonstrated superior detection sensitivity in the benchmarking analysis, achieving Rc values approximately twice as high as those obtained with the 3D UTE BSSFP method. The technique successfully facilitated imaging and precise localization of 19 F hotspots in postmortem experiments. However, it is important to highlight that imaging 10 mM PFOB in small mice postmortem, utilizing a 48 × 48 × 48 3D scan, demanded a substantial scan time of 1 h and 45 min. Further studies will explore accelerated imaging techniques, such as compressed sensing, to enhance BaSSI's clinical utility.


Assuntos
Fluorocarbonos , Hidrocarbonetos Bromados , Camundongos , Animais , Flúor , Imageamento por Ressonância Magnética/métodos , Imageamento Tridimensional/métodos
20.
Sci Total Environ ; 907: 168057, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-37898190

RESUMO

Hexabromocyclododecanes (HBCDs) have become a global pollution problem, particularly in China-a major producer and user of HBCDs. However, little is known about the HBCD pollution status in urban rivers nationwide in China. In this study, we comprehensively investigated the pollution characteristics of HBCDs in 173 sediment samples from black-odorous urban rivers across China. Total HBCD concentrations ranged from not-detected to 848 ng/g dw, showing significant differences among the various sampling cities, but generally increasing from west to east China. This distribution pattern of HBCDs was strongly associated with the local industrial output, gross domestic product, and daily wastewater treatment capacity. α-HBCD was the predominant diastereoisomer in most sediments, with an average proportion of 63.8 ± 18.8 %, followed by γ-HBCD (23.8 ± 19.5 %) and ß-HBCD (12.4 ± 6.49 %), showing a significant increase of the α-HBCD proportions relative to those in HBCD commercial mixtures and an opposite trend for that of γ-HBCD. These results suggested that HBCDs might undergo isomerization from γ- to α-HBCD and biotic/abiotic degradation with preference for γ-HBCD. Of these conversions, the microbial degradation of HBCDs was further verified by the preferential transformation of (-)-α-, (+)-ß-, and (-)-γ-HBCDs and the detection of HBCD-degrading bacteria, including Dehalococcoides, Bacillus, Sphingobium, and Pseudomonas. A risk assessment indicated that HBCDs pose low to moderate risks to aquatic organisms in most black-odorous urban river sediments.


Assuntos
Retardadores de Chama , Hidrocarbonetos Bromados , Rios , Monitoramento Ambiental/métodos , Sedimentos Geológicos , Hidrocarbonetos Bromados/análise , China , Medição de Risco , Retardadores de Chama/análise
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