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1.
J Wound Care ; 33(8): 570-576, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39137253

RESUMO

OBJECTIVE: Acute laceration wound (ALW) is one of the most common injuries in Indonesia with potential significant morbidities. In rural areas, povidone-iodine and honey are commonly used as wound dressings. This study aimed to identify the effectiveness of honey compared to paraffin gauze and the commonly used povidone-iodine in improving ALW healing time. METHOD: This study was a single-blind, pilot randomised controlled trial (RCT) with three intervention groups (honey, povidone-iodine, and paraffin). The outcomes were wound healing time, slow healing, secondary healing, signs of infection, wound dehiscence, oedema, maceration, necrosis, exudate and cost. RESULTS: A total of 35 patients (male to female ratio: 4:1), with a mean age of 22.5 (range: 6-47) years, were included and randomised to treatment groups using predetermined randomisation according to wound location and wound dressing selection: honey group, n=12; povidone-iodine group, n=11; paraffin group, n=12 with one patient lost to follow-up. All groups achieved timely healing, with a mean healing time of 9.45±5.31 days and 11.09±5.14 days for the povidone-iodine and paraffin groups, respectively, and a median healing time of 10 (3-19) days for the honey group (p>0.05). More wounds in the honey group achieved healing in ≤10 days compared with the other groups. Both povidone-iodine and honey groups had fewer adverse events, with the latter having the lowest cost. CONCLUSION: In this study, honey was clinically effective in accelerating healing time with a lower cost compared to paraffin, and was comparable to povidone-iodine. Future RCTs with a larger sample size should be pursued to determine honey's role in ALW treatment.


Assuntos
Anti-Infecciosos Locais , Mel , Lacerações , Povidona-Iodo , Cicatrização , Humanos , Povidona-Iodo/uso terapêutico , Cicatrização/efeitos dos fármacos , Masculino , Feminino , Adulto , Projetos Piloto , Pessoa de Meia-Idade , Adolescente , Método Simples-Cego , Anti-Infecciosos Locais/uso terapêutico , Lacerações/terapia , Adulto Jovem , Criança , Indonésia , Bandagens , Parafina/uso terapêutico , Resultado do Tratamento
2.
Environ Sci Technol ; 58(33): 14797-14811, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39120259

RESUMO

Short-, medium-, and long-chain chlorinated paraffins (CPs) (SCCPs, MCCPs, and LCCPs) and dechloranes are chemicals of emerging concern; however, little is known of their bioaccumulative potential compared to legacy contaminants in marine mammals. Here, we analyzed SCCPs, MCCPs, LCCPs, 7 dechloranes, 4 emerging brominated flame retardants, and 64 legacy contaminants, including polychlorinated biphenyls (PCBs), in the blubber of 46 individual marine mammals, representing 10 species, from Norway. Dietary niche was modeled based on stable isotopes of nitrogen and carbon in the skin/muscle to assess the contaminant accumulation in relation to diet. SCCPs and dechlorane-602 were strongly positively correlated with legacy contaminants and highest in killer (Orcinus orca) and sperm (Physeter macrocephalus) whales (median SCCPs: 160 ng/g lw; 230 ng/g lw and median dechlorane-602: 3.8 ng/g lw; 2.0 ng/g lw, respectively). In contrast, MCCPs and LCCPs were only weakly correlated to recalcitrant legacy contaminants and were highest in common minke whales (Balaenoptera acutorostrata; median MCCPs: 480 ng/g lw and LCCPs: 240 ng/g lw). The total contaminant load in all species was dominated by PCBs and legacy chlorinated pesticides (63-98%), and MCCPs dominated the total CP load (42-68%, except 11% in the long-finned pilot whale Globicephala melas). Surprisingly, we found no relation between contaminant concentrations and dietary niche, suggesting that other large species differences may be masking effects of diet such as lifespan or biotransformation and elimination capacities. CP and dechlorane concentrations were higher than in other marine mammals from the (sub)Arctic, and they were present in a killer whale neonate, indicating bioaccumulative properties and a potential for maternal transfer in these predominantly unregulated chemicals.


Assuntos
Poluentes Orgânicos Persistentes , Animais , Noruega , Poluentes Orgânicos Persistentes/metabolismo , Hidrocarbonetos Clorados/metabolismo , Parafina/metabolismo , Mamíferos/metabolismo , Monitoramento Ambiental , Retardadores de Chama/metabolismo , Dieta , Bifenilos Policlorados/metabolismo
3.
Tissue Cell ; 90: 102511, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39141933

RESUMO

Precision-cut liver slices (PCLS) are tissue explants extensively used as an ex vivo model for metabolism and toxicity studies. When in vitro assays are conducted, it is imperative to perform a histomorphological evaluation as part of the viability analyses throughout the assay time. It is considered that good quality PCLS histological sections are difficult to obtain because they are hard to manipulate, and may shrink or fold during processing. Moreover, bibliography is not detailed on the embedding processes used. In this article, we propose an adjusted and rapid method for paraffin embedding of PCLS from crossbreed steers. Each PCLS was covered with a piece of gauze and placed into a histological cassette. These cassettes were submitted to a series of baths: 80 % ethanol for 10 min; 3 baths of 96 % ethanol for 10 min; 3 baths of butanol for 10 min; 1 bath of butanol-paraffin (1:1) for 20 min in a 60 °C laboratory oven; and 3 baths of paraffin for 20 min in a 60 °C laboratory oven. Folded paper boxes were used to produce paraffin blocks. It was possible to obtain complete sections with preserved cell morphology and no artifacts, and tissue appearance was similar to previous PCLS processed through the routine protocol, demonstrating the adequacy of the method implemented.


Assuntos
Fígado , Inclusão em Parafina , Inclusão em Parafina/métodos , Fígado/citologia , Animais , Bovinos , Parafina , Masculino
4.
Environ Sci Technol ; 58(35): 15428-15437, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39172767

RESUMO

Medium-chain chlorinated paraffins (MCCPs, C14-C17) are frequently detected in diverse environmental media. It has been proposed to be listed in Annex A of the Convention on Persistent Organic Pollutants in 2023. Although MCCPs are a crucial health concern, their toxicity remains unclear. This study investigated the toxic effects of MCCPs (0.1-50 mg/kg body weight/day) on the thyroid gland of female Sprague-Dawley rats and characterized the potential toxic pathways via transcriptomics and metabolomics approaches. MCCPs exposure caused histopathological changes to the endoplasmic reticula and mitochondria in thyroid follicular cells at a dose of 50 mg/kg bw/d and increased serum thyrotropin-releasing hormone, thyroid-stimulating hormones, and thyroxine when exposed to a higher dose of MCCPs. Transcriptomic analysis indicated the excessive expression of key genes related to thyroid hormone synthesis induced by MCCPs. Integrating the dual-omics analysis revealed mitochondrial dysfunction of the thyroid by mediating fatty acid oxidation, Kreb's cycle, and oxidative phosphorylation. Significant metabolic toxicity on the thyroid might be linked to the characteristics of the chlorine content of MCCPs. This study revealed the toxicity of MCCPs to the thyroid gland via triggering thyroid hormone synthesis and interfering with mitochondrial function, which can provide new insights into the modes of action and mechanism-based risk assessment of MCCPs.


Assuntos
Mitocôndrias , Parafina , Ratos Sprague-Dawley , Glândula Tireoide , Hormônios Tireóideos , Ratos , Glândula Tireoide/efeitos dos fármacos , Glândula Tireoide/metabolismo , Hormônios Tireóideos/metabolismo , Animais , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Feminino
5.
Water Res ; 265: 122300, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39173360

RESUMO

The Tibetan Plateau, a recognized global sink for Persistent Organic Pollutants (POPs), lies adjacent to two major emitting regions, inland China and India. This unique geographical setting makes it a pivotal site for examining the presence and compositional evolution of POPs following their long-range atmospheric transport (LRAT). This study focuses on the current predominant POPs, chlorinated paraffins (CPs). We comprehensively screened 675 homologues of the very short- (vSCCPs), short- (SCCPs), medium- (MCCPs), and long-chain CPs (LCCPs) in six dated sediment cores across the extensive Tibetan area. The findings unveiled pronounced temporal disparities in CP concentrations and compositions between Tibet's southern and eastern sectors, reflecting divergent usage and emission chronicles of inland China and India. Notably, a market shift in China from regulated SCCPs to the in-use MCCPs and LCCPs was observed in the 21st century, contrasting with India's unregulated production of SCCPs. The Organization for Economic Cooperation and Development (OECD) Screening Tool, developed to assess the overall persistence (POV) and long-range transport potential (LRTP) of organic chemicals, elucidated the erosion of CP source signatures induced by fractionation, a process that intensifies with transport distance from the source regions. This study enhances our understanding of the emission inventories and LRAT behavior of these transitional regulatory contaminants, highlighting the Tibetan Plateau's crucial role as an environmental sentinel in global pollution dynamics.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos , Lagos , Tibet , Lagos/química , Sedimentos Geológicos/química , Hidrocarbonetos Clorados , Parafina , Atmosfera/química , Poluentes Químicos da Água
6.
J Hazard Mater ; 476: 135056, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-38981235

RESUMO

To address the problem of the weak natural restoration ability of oligotrophic groundwater environments, a novel N/P controlled-release material (CRM) for biostimulation, prepared by an improved method, was developed. CRMs can encapsulate N and P (N/P) salts for sustained release in aquifers. Paraffin-based CRMs can be used to control N/P release rates by adjusting the particle size of CRMs and the mass ratio of the paraffin. The developed CRMs had a more remarkable adaptability to groundwater than other materials. Specifically, 0.4-cm CRMs released N/P stably and efficiently over a wide temperature range (7-25 â„ƒ), and the release properties of various CRMs were not affected by pH. The release of N/P followed Fickian diffusion, and a dissolution-diffusion model was established to elucidate the mechanism of the controlled release. In contrast to bare N/P, CRMs obviously enhanced the biodegradation rate of phenol and prolonged the effectiveness of supplying N/P. The degradation rate of phenol in the CRM system increased by 20.8 %. The different supply modes of N/P, CRMs and bare N/P, resulted in differences in salinity. Metagenomic analysis showed that this difference changed the proportion of various phenol-degrading genera and thus changed the abundance of genes associated with the phenol degradation pathway.


Assuntos
Biodegradação Ambiental , Água Subterrânea , Parafina , Fenol , Poluentes Químicos da Água , Água Subterrânea/química , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/química , Fenol/metabolismo , Fenol/química , Parafina/química , Parafina/metabolismo , Nitrogênio/metabolismo , Nitrogênio/química , Fósforo/química , Fósforo/metabolismo , Preparações de Ação Retardada , Salinidade
7.
Environ Sci Technol ; 58(31): 13658-13667, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39056270

RESUMO

The prevalence and distribution of chlorinated paraffins (CPs) have been extensively studied in various matrices and organisms; however, there is a lack of information about insects, particularly in honeybees. To address this gap, we studied young honeybee workers exposed to short- and medium-chain CPs (SCCPs and MCCPs) at an environmentally relevant concentration of 10 mg/L for 7 days, followed by a 7-day elimination period. Results indicated that CPs could transfer into the head after oral consumption and SCCPs and MCCPs exhibited clear bioaccumulation trends: midgut > hindgut > head. An evaluation of congener group distribution patterns demonstrated that the dominant congener groups in all target tissues were C11-13Cl7-8 and C14Cl7-8 for SCCPs and MCCPs, respectively, consistent with the treated CP standards. In honeybees, a significant negative relationship was observed for the log concentration of MCCP congener groups and their log KOW, but not with their log KOA. Conversely, no such correlation was found for SCCPs. These findings suggest that honeybees have a high potential to bioaccumulate MCCPs, particularly those with a low log KOW, and exhibit weak selectivity for SCCPs.


Assuntos
Parafina , Animais , Abelhas , Parafina/metabolismo , Hidrocarbonetos Clorados/metabolismo , Administração Oral
8.
Environ Pollut ; 359: 124559, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39019312

RESUMO

Contaminant accumulation in organisms can be influenced by both biological traits and environmental conditions. However, delineating the main factors affecting contaminant burdens in organisms remains challenging. Here, we conducted an initial investigation into the impact of diet and habitat on the accumulation of short- (SCCPs) and medium-chain chlorinated paraffins (MCCPs) in Indo-Pacific humpback dolphins (2003-2020, n = 128) from the Pearl River Estuary (PRE), a highly polluted estuary in China. The detected levels of SCCPs (5897 ± 3480 ng g-1 lw) and MCCPs (13,960 ± 8285 ng g-1 lw) in blubber samples of humpback dolphin are the highest among recorded values marine mammals. Both SCCPs and MCCPs exhibited biomagnification factor values exceeding 1, suggesting their biomagnification potential within the dolphins and their diet. Quantitative diet analysis using the dolphin fatty acid signatures revealed that humpback dolphins inhabiting the western PRE consumed a larger proportion of carnivorous fish than those from the eastern PRE. However, spatial analysis showed that humpback dolphins in the western PRE contained lower SCCP/MCCP concentrations than those from the eastern PRE. Based on these findings we suggest that, compared to diet differences, spatial variations of SCCPs/MCCPs in humpback dolphins may be predominantly influenced by their space-use strategies, as the eastern PRE is closer to the pollutant discharge source and transfer routes.


Assuntos
Golfinhos , Monitoramento Ambiental , Parafina , Poluentes Químicos da Água , Animais , Parafina/análise , Parafina/metabolismo , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/metabolismo , Golfinhos/metabolismo , China , Estuários , Hidrocarbonetos Clorados/metabolismo , Hidrocarbonetos Clorados/análise , Ecossistema , Dieta/veterinária
9.
J Hazard Mater ; 476: 135169, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39024769

RESUMO

Human dermal exposure to chlorinated paraffins (CPs) has not been well documented. Therefore, hand wipes were collected from four occupational populations to analyze short-chain CPs (SCCPs) and medium-chain CPs (MCCPs) in order to estimate dermal uptake and oral ingestion via hand-to-mouth contact. The total CP levels (∑SCCPs and ∑MCCPs) in wipes ranged from 71.4 to 2310 µg/m2 in security guards, 37.6 to 333 µg/m2 in taxi drivers, 20.8 to 559 µg/m2 in office workers, and 20.9 to 932 µg/m2 in undergraduates, respectively. Security guards exhibited the highest levels of ∑SCCPs among four populations (p < 0.01). In undergraduates engaged in outdoor activities, C13 emerged as the most dominant SCCPs homologue group, followed by C12, C11, and C10. The levels of ∑SCCPs and ∑MCCPs in males in light haze pollution were significantly higher than that in heavy haze pollution (p < 0.05). The median estimated dermal absorption dose of SCCPs and MCCPs via hand was 22.2 and 104 ng (kg of bw)-1 day-1, respectively, approximately 1.5 times the oral ingestion [12.3 and 74.4 ng (kg of bw)-1 day-1], suggesting that hand contact is a significant exposure source to humans.


Assuntos
Exposição Ocupacional , Parafina , Absorção Cutânea , Humanos , Masculino , Parafina/análise , Feminino , Exposição Ocupacional/análise , Adulto , Hidrocarbonetos Clorados/análise , Hidrocarbonetos Clorados/toxicidade , Hidrocarbonetos Clorados/farmacocinética , Adulto Jovem , Fatores Sexuais , Pele/metabolismo , Pele/efeitos dos fármacos
10.
Anal Chim Acta ; 1315: 342757, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38879205

RESUMO

BACKGROUND: Chlorinated paraffins (CPs) are industrial chemicals categorised as persistent organic pollutants because of their toxicity, persistency and tendency to long-range transport, bioaccumulation and biomagnification. Despite having been the subject of environmental attention for decades, analytical methods for CPs still struggle reaching a sufficient degree of accuracy. Among the issues negatively impacting the quantification of CPs, the unavailability of well-characterised standards, both as pure substances and as matrix (certified) reference materials (CRMs), has played a major role. The focus of this study was to provide a matrix CRM as quality control tool to improve the comparability of CPs measurement results. RESULTS: We present the process of certification of ERM®-CE100, the first fish reference material assigned with certified values for the mass fraction of short-chain and medium-chain chlorinated paraffins (SCCPs and MCCPs, respectively). The certification was performed in accordance with ISO 17034:2016 and ISO Guide 35:2017, with the value assignment step carried out via an intercomparison of laboratories of demonstrated competence in CPs analysis and applying procedures based on different analytical principles. After confirmation of the homogeneity and stability of the CRM, two certified values were assigned for SCCPs, depending on the calibrants used: 31 ± 9 µg kg-1 and 23 ± 7 µg kg-1. The MCCPs certified value was established as 44 ± 17 µg kg-1. All assigned values are relative to wet weight in the CRM that was produced as a fish paste to enhance similarity to routine biota samples. SIGNIFICANCE AND NOVELTY: The fish tissue ERM-CE100 is the first matrix CRM commercially available for the analysis of CPs, enabling analytical laboratories to improve the accuracy and the metrological traceability of their measurements. The certified CPs values are based on results obtained by both gas and liquid chromatography coupled with various mass spectrometric techniques, offering thus a broad validity to laboratories employing different analytical methods and equipment.


Assuntos
Hidrocarbonetos Clorados , Parafina , Padrões de Referência , Hidrocarbonetos Clorados/análise , Parafina/análise , Parafina/química , Animais , Peixes
11.
Swiss Dent J ; 134(3): 18-34, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38864504

RESUMO

This study investigated and compared the consistency and compressive strength of two commercially available paraffin wax chewing gums (Aurosan (AU) and GC Europe (GC)), as well as their impact on stimulated salivary flow rate. Instrumental texture analysis was uti-lized to assess the consistency and compressive strength of AU and GC during a 7-min chewing period. Subsequently, stimulated salivary flow rate (sSFR) was evaluated in healthy subjects using AU and GC over a 7-minute period. The compressive strengths from the pre-liminary test were compared over time with the sialometry data. Eighty-one test subjects, comprising 33 men and 48 women, participated. Over the 7-min measurement period, dif-ferences were observed in the total amount of saliva accumulated per minute. Direct com-parison of AU and GC revealed that regardless of age and gender, the amount of saliva formed after 1 min was 0.63 times less with AU than with GC (95% CI: 0.56 - 0.70; P < 0.001). The accumulated saliva volume with AU was also significantly lower than that with GC in the first 4 min (P = 0.016). However, from minute 5 onwards, the two products no longer showed statistical differences in the total amount of saliva. Comparison of the com-pressive strength of AU and GC showed that the values after 1 and 2 min were significantly higher for AU than for GC (P < 0.05); for all other time points, the compressive strength was higher for GC. In the mixed-effects model after log-transformation of compressive strength and saliva volume, GC exhibited decreasing saliva volumes with increasing compressive strength (P <0.001). Conversely, the opposite was observed for AU (P = 0.019). The study suggests that the consistency or compressive strength of paraffin wax chewing gums from different manufacturers could impact sSFR.


Assuntos
Goma de Mascar , Parafina , Saliva , Humanos , Feminino , Masculino , Adulto , Saliva/química , Força Compressiva/fisiologia , Mastigação/fisiologia , Adulto Jovem , Pessoa de Meia-Idade , Taxa Secretória/fisiologia , Taxa Secretória/efeitos dos fármacos
12.
BMC Public Health ; 24(1): 1648, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38902608

RESUMO

BACKGROUND: Injury due to ingestion of harmful chemicals has become an area of concern globally. In South Africa, paraffin has been widely implicated in multiple health outcomes, including severe ingestion injuries. A specific category of such injuries is those that are self-inflicted. A significant proportion of self-inflicted ingestion is reported to be intentional, although intentionality for self-infliction may be difficult to determine. Nonetheless, the identification of key explanatory risks and demographic factors of self-inflicted ingestion may contribute towards a better understanding of self-inflicted and harmful chemical ingestion injuries. METHODS: This study used secondary data that had been collected on burn injuries of all causes, including those due to the ingestion of harmful chemicals, from a sample of South Africans from low-income communities close to major metropolitan centres. The current analysis focused on the risks for self-inflicted ingestion injuries and used logistic regression to determine risks for self-inflicted ingestion as differentiated from ingestion due to the actions of another person (other-inflicted ingestion) by sex and age cohort of the victim, and the presence of alcohol, by examining paraffin ingestion versus that of other chemicals. RESULTS: The overwhelming majority of ingestion injuries (92.1%) were self-inflicted. The current findings indicate that sex (with females almost twice as likely to present with self-inflicted ingestion), age cohort (with those aged 18-29 and 30-44 years old four times more likely affected than older adults), presence of alcohol (twice as likely present than amongst individuals reporting ingestion injuries inflicted by others), and chemicals other than paraffin (three times more likely) are key explanatory factors for an increased risk for self-inflicted ingestion of harmful chemicals. CONCLUSIONS: The study empirically confirms the role of several key risk factors in what remains a relatively unreported and understudied phenomenon, but which appears to align with the demographic and risk profile reported for suicidal injuries through chemical ingestion, i.e. intentional self-inflicted ingestion. The findings may contribute towards improved safety policies on the availability and sale of chemical products and more focussed community interventions for at-risk individuals such as females and young people. It also flags the importance of assessing for alcohol use and alcohol use disorders at hospital admission of self-ingestion injuries.


Assuntos
Comportamento Autodestrutivo , Humanos , Feminino , Masculino , Adolescente , África do Sul/epidemiologia , Adulto , Comportamento Autodestrutivo/epidemiologia , Fatores de Risco , Adulto Jovem , Parafina , Pessoa de Meia-Idade , Queimaduras/epidemiologia
13.
J Hazard Mater ; 474: 134759, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-38823100

RESUMO

Short- and medium-chain chlorinated paraffins (SCCPs and MCCPs) are hazardous industrial chemicals that tend to bioaccumulate in animal-derived foodstuffs through the food supply chain. However, the lack of reliable noninvasive bioindicators hinders the monitoring of farm animal exposure to CPs. In this study, 169 cattle hair samples were collected from beef cattle farms in six Chinese provinces, with further beef, feed, and soil samples being collected in Hebei province. Geographical differences in CP concentrations were observed in the hair samples, and CP concentrations in samples collected from Hebei province decreased in the following order: hair > feed > beef > soil. C10-11Cl6-7 and C14Cl7-8 were the predominant SCCPs and MCCPs, respectively, in all the hair, beef, feed, and soil samples. CP concentrations in hair samples significantly correlated with those in beef, feed, and soil samples, indicating that hair can be used as a bioindicator of cattle exposure to CPs. The possible health risks associated with exposure to CPs through beef consumption, especially for children and high-volume beef consumers, should be further investigated.


Assuntos
Cabelo , Parafina , Animais , Bovinos , Cabelo/química , Parafina/análise , China , Hidrocarbonetos Clorados/análise , Ração Animal/análise , Monitoramento Ambiental/métodos , Fazendas , Poluentes do Solo/análise , Poluentes Ambientais/análise , Contaminação de Alimentos/análise
14.
Int J Biol Macromol ; 275(Pt 1): 133533, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38945339

RESUMO

Firefighting clothing is an indispensable protective equipment for firefighters performing rescue activities under extreme heat and fire conditions. However, few bio-based thermal management materials that provide thermal comfort to firefighters in different operational scenarios have been reported. Herein, we present a novel strategy to prepare Janus-type aerogels based on sodium alginate biological macromolecules, consisting of a SiO2 nanoparticle layer and a microencapsulated paraffin@SiO2 phase-change composite layer. A passive radiative cooling and thermal energy storage was integrated into a functional dual-mode material system. Results show that Janus-type aerogel to cool down by 11.5 °C on a hot summer day. Meanwhile, paraffin@SiO2 has a high melting enthalpy of 127.5 J g-1 that effectively buffers temperature rise during the phase-change process. This Janus-type aerogel has ultra-low heat insulation (0.042 W/(m·K)), it can delay approximately 76.6 s to reach second-degree burn time for skin at a radiant heat exposure of 18.4 kW m-2. The work provides an innovative way to develop bio-based thermal management materials, which could enable multi-scenario thermal management for firefighting clothing.


Assuntos
Alginatos , Alginatos/química , Dióxido de Silício/química , Roupa de Proteção , Géis/química , Condutividade Térmica , Humanos , Temperatura Alta , Parafina/química , Nanopartículas/química , Bombeiros
15.
Chemosphere ; 358: 142225, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38705415

RESUMO

Short-chain and medium-chain chlorinated paraffins (SCCPs and MCCPs) have garnered significant attention because they have persistence and potential toxicity, and can undergo long-distance transport. Chlorinated paraffins (CPs) inhaled in the size-fractionated particulate phase and gas phase can carry different risks to human health due to their ability to accumulate in different regions of the respiratory tract and exhibit varying deposition efficiencies. In our study, large-volume ambient air samples in both the size-fractionated particulate phase (Dp < 1.0 µm, 1.0-2.5 µm, 2.5-10 µm, and Dp ≥ 10 µm) and gas phase were collected simultaneously in Beijing using an active sampler. The overall levels of SCCPs and MCCPs were relatively high, the ranges being 57-881 and 30-385 ng/m3, respectively. SCCPs tended to be partitioned in the gas phase (on average 75% of the ΣSCCP concentration), while MCCPs tended to be partitioned in the particulate phase (on average 62% of the ΣMCCP concentration). Significant correlations were discovered between the logarithm-transformed gas-particle partition coefficients (KP) and predicted subcooled vapor pressures (PL0) (p < 0.01 for SCCPs and MCCPs) and between the logarithm-transformed KP values and octanol-air partition coefficients (KOA) (p < 0.01 for SCCPs and MCCPs). Thus, the slopes indicated that organic matter absorption was the dominant process involved in gas-particle partitioning. We used the ICRP model to calculate deposition concentrations for particulate-associated CPs in head airways region (15.6-71.4 ng/m³), tracheobronchial region (0.8-4.8 ng/m³), and alveolar region (5.1-21.9 ng/m³), then combined these concentrations with the CP concentrations in the gas phase to calculate estimated daily intakes (EDIs) for inhalation. The EDIs for SCCPs and MCCPs through inhalation of ambient air for the all-ages group were 67.5-184.2 ng/kg/day and 19.7-53.7 ng/kg/day, respectively. The results indicated that SCCPs and MCCPs in ambient air do not currently pose strong risks to human health in the study area.


Assuntos
Poluentes Atmosféricos , Monitoramento Ambiental , Hidrocarbonetos Clorados , Parafina , Tamanho da Partícula , Material Particulado , Parafina/análise , Poluentes Atmosféricos/análise , Humanos , Material Particulado/análise , Hidrocarbonetos Clorados/análise , Medição de Risco , Exposição por Inalação/análise , Exposição por Inalação/estatística & dados numéricos , Pequim , Halogenação , Gases/análise
17.
Environ Sci Pollut Res Int ; 31(26): 38358-38366, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38801611

RESUMO

Concentrations of short- and medium-chain chlorinated paraffins (SCCPs and MCCPs) were analyzed and investigated in surficial sediment collected in 2018 from ten different nearshore sites in Lake Ontario and the St. Lawrence River influenced by inputs from varying urban and historical land uses. Sites were grouped into two categories of tributary and lake according to their location. Results show that tributary sites had higher concentrations of total chlorinated paraffin (CP) than lake sites. Humber Bay, a lake site, had the highest total CP concentration (55,000 ng/gTOC) followed by Humber River, a tributary site (50,000 ng/gTOC). The lowest concentrations were found in eastern Lake Ontario and Lake St. Francis in the St. Lawrence River (540 ng/gTOC). Higher concentrations of chlorinated paraffins (CPs) were found where runoff and wastewater inputs from urban areas, current industrial activities, and population were the greatest. Levels of MCCPs were higher than SCCPs at all sites but one, Lake St. Francis. Among the SCCPs, C13 and among the MCCPs C14 were the dominant chain length alkanes, with C14 being the highest among both groups. The SCCPs and MCCPs profiles suggest that they can be used to distinguish between sites impacted by local sources vs. sites impacted by short-/long-range transport of these chemicals.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos , Lagos , Parafina , Poluentes Químicos da Água , Lagos/química , Parafina/análise , Poluentes Químicos da Água/análise , Sedimentos Geológicos/química , Ontário , Hidrocarbonetos Clorados/análise
18.
J Cancer Res Clin Oncol ; 150(4): 172, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38565653

RESUMO

PURPOSE: Visualizing mitochondria in cancer cells from human pathological specimens may improve our understanding of cancer biology. However, using immunohistochemistry to evaluate mitochondria remains difficult because almost all cells contain mitochondria and the number of mitochondria per cell may have important effects on mitochondrial function. Herein, we established an objective system (Mito-score) for evaluating mitochondria using machine-based processing of hue, saturation, and value color spaces. METHODS: The Mito-score was defined as the number of COX4 (mitochondrial inner membrane) immunohistochemistry-positive pixels divided by the number of nuclei per cell. The system was validated using four lung cancer cell lines, normal tissues, and lung cancer tissues (199 cases). RESULTS: The Mito-score correlated with MitoTracker, a fluorescent dye used to selectively label and visualize mitochondria within cells under a microscope (R2 = 0.68) and with the number of mitochondria counted using electron microscopy (R2 = 0.79). Histologically, the Mito-score of small cell carcinoma (57.25) was significantly lower than that of adenocarcinoma (147.5, p < 0.0001), squamous cell carcinoma (120.6, p = 0.0004), and large cell neuroendocrine carcinoma (111.8, p = 0.002). CONCLUSION: The Mito-score method enables the analysis of the mitochondrial status of human formalin-fixed paraffin-embedded specimens and may provide insights into the metabolic status of cancer.


Assuntos
Formaldeído , Neoplasias Pulmonares , Humanos , Parafina , Inclusão em Parafina , Mitocôndrias , Coloração e Rotulagem
19.
Crit Rev Toxicol ; 54(4): 235-251, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38656260

RESUMO

Some studies suggested that gastrointestinal (GIT) decontamination with oil may improve the prognosis of patients who ingested aluminum phosphide (AlP). The aim of this study is to compare the efficacy and safety of gastric lavage with oil-based solutions to any method of gastric decontamination not using oils in patients presenting with acute AlP poisoning. The literature was searched for English-published randomized controlled trials (RCTs) from inception to 16 September 2023. The searched electronic databases included MEDLINE/PubMed, Cochrane Library, Web of Science, Egyptian Knowledge Bank, Scopus, and Google Scholar. Data were extracted and pooled by calculating the risk ratio (RR) for categorical outcomes and standardized mean difference (SMD) for numerical outcomes, with 95% confidence intervals (CI). Seven RCTs were included. Paraffin oil was significantly associated with a lower risk of mortality (RR = 0.59 [95% CI: 0.45, 0.76], p < .001), intubation (RR = 0.59 [95% CI: 0.46, 0.76], p < .001) and vasopressor need (RR = 0.71 [95% CI: 0.56, 0.91], p = .006). Survival time was significantly prolonged with paraffin oil (SMD = 0.72 [95% CI: 0.32, 1.13], p < .001). Coconut oil was significantly associated with prolonged survival time (SMD = 0.83 [95% CI: 0.06, 1.59], p = .03) as well as decreased risk of requiring intubation (RR = 0.78 [95% CI: 0.62, 0.99], p = .04). Oil-based GIT decontamination using paraffin oil showed benefits over conventional lavage regarding the incidence of in-hospital mortality and endotracheal intubation, and survival time. Coconut oil showed some benefits in terms of the intubation incidence and survival time. Decontamination using paraffin oil is recommended. Future clinical trials are warranted with larger sample sizes and focusing on cost-benefit and safety.


Assuntos
Compostos de Alumínio , Lavagem Gástrica , Fosfinas , Humanos , Compostos de Alumínio/intoxicação , Lavagem Gástrica/métodos , Óleos , Parafina , Praguicidas , Fosfinas/intoxicação , Intoxicação , Ensaios Clínicos Controlados Aleatórios como Assunto
20.
Sci Total Environ ; 928: 172435, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38615758

RESUMO

Knowledge regarding the occurrence of short-chain and medium-chain chlorinated paraffins (SCCPs and MCCPs) in foodstuffs and their dietary exposure risks for rural Tibetan residents remains largely unknown. Herein, we collected main foodstuffs (including highland barley, vegetables, Tibetan butter, mutton, and yak beef) across the rural Tibetan Plateau and characterized the CP profiles and concentrations. The highest SCCPs concentrations were detected in Tibetan butter (geometric mean (GM): 240.6 ng/g wet weight (ww)), followed by vegetables (59.4 ng/g ww), mutton (51.4 ng/g ww), highland barley (46.3 ng/g ww), and yak beef (31.7 ng/g ww). For MCCPs, the highest concentrations were also detected in Tibetan butter (319.5 ng/g ww), followed by mutton (181.9 ng/g ww), vegetables (127.0 ng/g ww), yak beef (71.2 ng/g ww), and highland barley (30.3 ng/g ww). The predominant congener profiles of SCCPs were C13Cl7-8 in mutton and yak beef, C10Cl7-8 in Tibetan butter, and C10-11Cl6-7 in highland barley and vegetables. The predominant congener profiles of MCCPs were C14Cl7-9 in all sample types. Combined with our previous results of free-range chicken eggs, the median estimated daily intakes (EDIs) of SCCPs and MCCPs via diet for Tibetan rural adults and children was estimated to be 728.8 and 1853.9 ng/kg bw/day and 2565.6 and 5952.8 ng/kg bw/day, respectively. In the worst scenario, MCCPs might induce potential health risks for rural Tibetan population. To our knowledge, this is the first systematic dietary exposure research of SCCPs and MCCPs in the remote rural areas.


Assuntos
Exposição Dietética , Parafina , População Rural , Tibet , Humanos , Exposição Dietética/estatística & dados numéricos , Exposição Dietética/análise , Parafina/análise , População Rural/estatística & dados numéricos , Adulto , Contaminação de Alimentos/análise , Contaminação de Alimentos/estatística & dados numéricos , Criança , Pessoa de Meia-Idade , Hidrocarbonetos Clorados/análise , Medição de Risco , Feminino , Masculino , China , Pré-Escolar , Adolescente , Adulto Jovem , Dieta/estatística & dados numéricos , Poluentes Ambientais/análise
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