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1.
Environ Sci Technol ; 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39106076

RESUMO

In this study, we measured 15 common organophosphate flame retardants (OPFRs) in six categories of tea samples across China. OPFRs were found in all the tea samples, with the total concentrations of OPFRs (∑OPFRs) at 3.44-432 ng/g [geometric mean (GM): 17.6 ng/g]. Triphenyl phosphate (TPhP) was the dominant OPFR, accounting for 39.0-76.2% of ∑OPFRs across all tea categories. The potential factors influencing the residual OPFRs in tea were thoroughly examined, including the agricultural environment, fermentation, and packaging of teas. Tea packaging materials (TPMs) were then identified as the primary sources of OPFRs in teas. The migration test revealed that OPFRs with lower molecular weights and log Kow values exhibited a higher propensity for facilitating the migration of OPFRs from TPMs to teas. The estimated daily intakes of OPFRs from teas were relatively higher for the general populations in Mauritania, Gambia, Togo, Morocco, and Senegal (3.18-9.79 ng/kg bw/day) than China (3.12 ng/kg bw/day). The health risks arising from OPFRs in Chinese teas were minor. This study established a baseline concentration and demonstrated the contamination sources of OPFRs in Chinese tea for the first time, with an emphasis on enhancing the hygiene standards for TPMs.

2.
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
3.
Environ Res ; 252(Pt 1): 118768, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38521355

RESUMO

Chlorinated paraffins (CPs) are hazardous to humans, and dietary intake acts as the primary pathway for human exposure to CPs. Takeout food is popular worldwide, but the presence of CPs in takeout food and its packaging is unclear. In this study, the concentrations and distributions of short- and median-chain CPs (SCCPs and MCCPs, respectively) were measured in 97 samples of four categories of takeout food and 33 samples of three types of takeout packaging. The SCCP and MCCP median concentrations for the takeout food samples were 248 and 339, 77.2 and 98.2, 118 and 258, 42.9 and 64.4 ng/g wet weight in meat, starch, half meat/half starch, and vegetables, respectively. Takeout food contained higher concentrations of SCCPs than MCCPs. The dominant SCCP and MCCP congener groups in takeout food were C10Cl6-7 and C14Cl7-8, respectively. The CP concentrations in takeout food were lower than those in packaging. The SCCP and MCCP median concentrations, respectively, in packaging were 9750 and 245 ng/g in polypropylene, 2830 and 135 ng/g in paper, and 2060 and 119 ng/g in aluminum foil. The concentrations of SCCPs and MCCPs were comparable in aluminum foil, whereas the concentrations of SCCPs were higher than those of MCCPs in polypropylene and paper. Correlations between CP concentrations in the takeout food and packaging indicated that CPs in packaging were potentially an important source of CPs in the takeout food. A dietary exposure risk assessment showed the takeout food posed a low risk for human exposure to CPs; however, high-frequency consumption may pose a health risk. This study clarified the current contamination situation in takeout food in Beijing, China. The resulting data could be used to prevent human exposure to CPs through dietary intake and to facilitate the market's control over the quality of takeout food.


Assuntos
Exposição Dietética , Contaminação de Alimentos , Embalagem de Alimentos , Parafina , Exposição Dietética/análise , Contaminação de Alimentos/análise , Parafina/análise , Humanos , Medição de Risco , Pequim , Hidrocarbonetos Clorados/análise , China
4.
Environ Res ; 246: 118109, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38185221

RESUMO

Chlorinated paraffins (CPs) in poultry feed and the farm environment might bioaccumulate in poultry eggs. Unlike chickens, which are mostly raised in cages, ducks are commonly raised free range. This would expose ducks to CPs in the environment. However, information on the presence of CPs on duck farms is scarce. In the present study, samples of duck eggs, duck feathers, poultry feed, and soil were collected from 25 duck farms in South China. Forty-eight congener groups of short- and medium-chain CPs (SCCPs and MCCPs) were detected in the samples. Interestingly, relatively high concentrations of SCCPs and MCCPs were found in the duck feathers. The median concentrations of SCCPs and MCCPs in the duck eggs, feathers, feed and soil were: 46 and 18 ng/g wet weight, 2460 and 992 ng/g, 103 and 47 ng/g, and 24 and 10 ng/g dry weight, respectively. The dominant groups of SCCPs and MCCPs were C10Cl6-7 and C14Cl7-8, respectively. The close relationship between duck feathers and poultry feed indicated that the duck feathers might act as a bioindicator for the exposure of ducks to CPs. The margin of exposure approach was used to assess the health risk, with the results showing that the consumption of duck eggs posed a low risk to different age groups from exposure to SCCPs and MCCPs.


Assuntos
Patos , Hidrocarbonetos Clorados , Animais , Parafina/análise , Fazendas , Exposição Dietética , Monitoramento Ambiental/métodos , Hidrocarbonetos Clorados/análise , Galinhas , China , Solo
5.
Environ Sci Technol ; 57(31): 11442-11451, 2023 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-37490655

RESUMO

Chlorinated paraffins (CPs) have become global pollutants and are of considerable concern as a result of their persistence and long-distance transmission in the environment and toxicity to mammals. However, their risks to pollinating insects are unknown. Honeybees are classical pollinators and sensitive indicators of environmental pollution. Herein, the effects of CPs on the gut microenvironment and underlying mechanisms were evaluated and explored using Apis mellifera L. Both short- and medium-chain CPs had significant sublethal effects on honeybees at a residue dose of 10 mg/L detected in bee products but did not significantly alter the composition or diversity of the gut microbiota. However, this concentration did induce significant immune, detoxification, and antioxidation responses and metabolic imbalances in the midgut. The mechanisms of CP toxicity in bees are complicated by the complex composition of these chemicals, but this study indicated that CPs could substantially affect intestinal physiology and metabolic homeostasis. Therefore, CPs in the environment could have long-lasting impacts on bee health. Future studies are encouraged to identify novel bioindicators of CP exposure to detect early contamination and uncover the detailed mechanisms underlying the adverse effects of CPs on living organisms, especially pollinating insects.


Assuntos
Abelhas , Poluentes Ambientais , Microbioma Gastrointestinal , Hidrocarbonetos Clorados , Parafina , Animais , Abelhas/fisiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Hidrocarbonetos Clorados/toxicidade , Parafina/toxicidade , Estresse Fisiológico , Poluentes Ambientais/toxicidade
6.
Clin Oral Investig ; 27(11): 6903-6914, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37831194

RESUMO

OBJECTIVES: Outstanding physical-mechanical properties and aging resistance are key requirements for dental resin composite since it will be placed in the oral environment for a long time. In this work, a new dental resin composite mainly modified by glass flakes was fabricated, and the aging resistance was evaluated by comparing with commercial composites without glass flakes. MATERIALS AND METHODS: The new dental resin composite was produced through hand blending of inorganic glass flakes/Si-Al-borosilicate glass (58wt%:7wt% of dental resin composite), POSS-MA (5wt% of resin matrix), Bis-GMA/TEGDMA(64.4wt%:27.6wt% of resin matrix), and CQ/EDMAB (0.9wt%:2.1wt% of resin matrix) together. The flexural strength, elasticity modulus, and hardness, as well as wear were tested for evaluating the aging resistance of different dental resin composite. RESULTS: Among 6 kinds of commercial composites in this study, after 6-month water storage, the maximum percentage of performance degradation is that the flexural strength decreased 39.96%, elasticity modulus decreased 51.53% and hardness decreased 12.52%. In contrast, the new synthesized material decreased 14.53%, 20.88%, and 0.61%, respectively, and performed lesser wear depth compared to some other groups (P < 0.05). CONCLUSIONS: It was observed that the new dental resin composite performed better performance stability and wear resistance when compared with commercial dimethacrylate-based or low shrinkage dental resin composite tested in this study. CLINICAL RELEVANCE: This possibly paves a path for designing tailored dental composite for practical application. Since the aging resistance of dental resin composite modified by glass flakes is superior, it has the potential to be used for promoting the durability of dental resin composite.


Assuntos
Resinas Compostas , Metacrilatos , Bis-Fenol A-Glicidil Metacrilato , Vidro , Módulo de Elasticidade , Teste de Materiais , Propriedades de Superfície
7.
Environ Res ; 215(Pt 2): 114361, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36130663

RESUMO

Animal derived foods are the primary pathway for human exposure to polychlorinated naphthalenes (PCNs), and various foodstuffs have been reported to contain PCNs. However, information on how PCN emission sources affect surrounding animal farms is scarce. The present study determined PCN levels in cow's milk, excrement, feed, plant and soil samples collected from four dairy farms situated within 10 km of an iron smelting plant in China. PCN concentrations in the milk samples from all four farms were in the range from 470 to 797 pg/g lipid weight while the PCN concentrations in the other specimens decreased in the order: plant > soil > excrement > feed. Higher PCN concentrations appeared in silage than in other feedstuffs, and the relationships between PCNs in milk, excrement and feed were closer than those in plant and soil. Human exposure risk to PCNs by consuming milk from this region was relatively higher than in less polluted areas.


Assuntos
Naftalenos , Animais , Bovinos , Humanos , China , Monitoramento Ambiental , Fazendas , Ferro , Lipídeos , Naftalenos/análise , Solo
8.
Environ Res ; 206: 112582, 2022 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-34929190

RESUMO

Polychlorinated naphthalenes (PCNs) are both highly toxic and bioaccumulative environmental contaminates. Dietary intake is the primary pathway for human exposure to PCNs, and PCN concentrations in aquatic foodstuffs are relatively high. Chinese mitten crab (Eriocheir sinensis) is one kind of popular aquatic foodstuffs in Asian countries. Farmed crabs could exposure to PCNs both through feed and environment. However, information on the occurrence of PCNs in farmed crabs is scarce. The present study investigated 75 PCN congeners in farmed Chinese mitten crabs, crab compound feed and sediments collected from Anhui Province and Shanghai in China. The total PCN concentrations in farmed Chinese mitten crabs from Anhui Province and Shanghai were 11.2-42.2 and 5.46-43.8 pg/g wet weight (ww), respectively. The PCN homologue profiles in crabs from both areas were similar, and both were dominated by di-CNs and penta-CNs. In contrast, lower chlorinated PCNs (di-CNs, tri-CNs and tetra-CNs) were the most common homologues in specimens of crab compound feed and sediment samples, indicating that selective bioaccumulation and metabolism of PCNs might occur in farmed crabs. No regional differences were found in the PCN congener profiles of farmed crabs, feed and sediment samples taken from Anhui Province and Shanghai. An assessment found no significant health risk associated with Chinese exposure to PCNs through farmed Chinese mitten crab consumption.


Assuntos
Naftalenos , Alimentos Marinhos , Ásia , China , Monitoramento Ambiental , Fazendas , Humanos , Naftalenos/análise , Alimentos Marinhos/análise
9.
Environ Sci Technol ; 54(19): 12130-12141, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-32936633

RESUMO

Organophosphate triesters (tri-OPEs) have recently been widely identified in aquatic ecosystems, but information on their organophosphate diester (di-OPE) metabolites is sparsely available. Herein, uniform fishmeal products were collected across the globe (the U.S., China, Europe, South America, and Southeast Asia). Sixteen representative tri-OPEs and eight di-OPEs were investigated to reveal whether industrial production, metabolism, environmental persistence, or physicochemical properties are the key factors influencing their environmental burden and distribution. Tri-OPEs and di-OPEs were 100% detected in fishmeal, with bis(2-chloroethyl) hydrogen phosphate (BCEP) and bis(1,3-dichloro-2-propyl) phosphate (BDCIPP) at discernible levels in marine fauna for the first time. Average concentration of di-OPEs (49.6 ± 27.5 ng/g dw) was of the same order of magnitude as that of tri-OPEs (59.3 ± 92.2 ng/g dw). Geographical-specific distributions of tris(2-chloroethyl) phosphate (TCEP), tris(2-chloroisopropyl) phosphate (TCIPP), triphenyl phosphate (TPhP), tris(2-butoxyethyl) phosphate (TBOEP), and 2-ethylhexyl diphenyl phosphate (EHDPP) were statistically significant (p < 0.05). Mean concentration ratios ranged from 0.087 for the BCEP-TCEP pair to 507 for the dimethyl phosphate (DMP)-trimethyl phosphate (TMP) pair. Only the TPhP-diphenyl phosphate (DPhP) pair presented a strong positive linear correlation (r = 0.731; p < 0.01), and DPhP was proved a degradation origin. Commercial sources had a significant overall impact on distribution patterns of the DMP-TMP and the dibutyl phosphate (DnBP) - tri-n-butyl phosphate (TnBP) pairs, whereas biotic transformation and abiotic stability profoundly influenced the bis(2-ethylhexyl) phosphate (BEHP)-tris(2-ethylhexyl) phosphate (TEHP), the bis(1-chloro-2-propyl) phosphate (BCIPP)-TCIPP, and the BCEP-TCEP pairs. Di-OPEs are critical to understand environmental behavior of tri-OPEs in marine fauna.


Assuntos
Retardadores de Chama , China , Ecossistema , Monitoramento Ambiental , Ésteres , Europa (Continente) , Retardadores de Chama/análise , Organofosfatos , América do Sul
10.
Appl Microbiol Biotechnol ; 104(12): 5461-5475, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32333053

RESUMO

Ergosterol is an important fungal-specific biomarker, but its use for fungal biomass estimation is still varied. It is important to distinguish between free and esterified ergosterols, which are mainly located on the plasma membrane and the cytosolic lipid particles, respectively. The present study analyzes free and esterified ergosterol contents in: (1) the fifty-nine strains of culturable fungi isolated from mangrove soil, (2) the broken spores of the fungus Ganoderma lucidum stored in capsule for more than 12 years, and (3) the mangrove soil and nearby campus wood soil samples by high performance liquid chromatography (HPLC). The results show that the contents of free and esterified ergosterols varied greatly in fifty-nine strains of fungi after 5 days of growth, indicating the diversity of ergosterol composition in fungi. The average contents of free and total ergosterols from the fifty-nine strains of fungi are 4.4 ± 1.5 mg/g and 6.1 ± 1.9 mg/g dry mycelia, respectively, with an average ergosterol esterification rate of 27.4%. The present study suggests that the fungi might be divided into two classes, one is fungi with high esterification rates (e.g., more than 27%) such as Nectria spp. and Fusarium spp., and the other is fungi with low esterification rates (e.g., less than 27%) such as Penicillium spp. and Trichoderma spp. Moreover, the ergosterol esterification rate in the spores of G. lucidum is 91.4% with a very small amount of free ergosterol (0.015 mg/g), compared with 41.9% with a higher level of free ergosterol (0.499 mg/g) reported in our previous study in 2007, indicating that free ergosterol degrades more rapidly than esterified ergosterol. In addition, the ergosterol esterification rates in mangrove soil and nearby campus wood soil samples range from 0 to 39.0%, compared with 80% in an old soil organic matter reported in a previous study, indicating the potential relationship between aging degree of fungi or soil and esterification rate. The present study proposes that both free and esterified ergosterols should be analyzed for fungal biomass estimation. When the ergosterol esterification rates in soils are higher, free ergosterol might be a better marker for fungal biomass. It is speculated that the ergosterol esterification rate in soils might contain some important information, such as the age of old-growth forests over time scales of centuries to millennia, besides the senescence degree of fungal mycelia in soils. KEY POINTS: • Fungi might be divided into two classes depending on ergosterol esterification rates. • Ergosterol esterification rate of broken spores stored for long time raised evidently. • Both free and esterified ergosterols should be analyzed for fungal biomass estimate. • Free ergosterol is a better marker for fungal biomass with a high esterification rate.


Assuntos
Ergosterol/química , Fungos/metabolismo , Microbiologia do Solo , Esporos Fúngicos/metabolismo , Biomassa , Cromatografia Líquida de Alta Pressão , Esterificação , Fungos/classificação , Fungos/isolamento & purificação , Micélio/metabolismo , Reishi/isolamento & purificação , Reishi/metabolismo , Áreas Alagadas
11.
Ecotoxicol Environ Saf ; 170: 306-313, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30530183

RESUMO

Novel brominated flame retardants (NBFRs), which are lipophilic compounds that have been widely applied after the phasing-out of legacy BFRs, can bioaccumulate through the food chain. However, information on NBFRs in animal feeds, the beginning of farm-to-fork pathway, is very limited. Fishmeal is one of the most widely applied feedstuff worldwide. The present study identified eleven NBFRs from ninety-two globally collected fishmeal samples with levels in the range of 0.13-822 (mean: 15.1 ±â€¯85.5) ng/g lipid weight (lw). Hexabromobenzene (HBB) and pentabromotoluene (PBT) were the most prevalent contributors (detection frequencies: 95.7% and 73.9%, respectively), and decabromodiphenylethane (DBDPE) was the weightiest contributor (accounted for 67.1% of the ΣNBFRs, mean: 12.1 ±â€¯84.8 ng/g lw). From a geographical view, the highest NBFR level was found in Chinese fishmeal. The NBFRs fell within an order of magnitude in South America, Southeast Asia, Europe and United States. DBDPE was predominant in the fishmeal collected from China, South America and United States, but it was not detected in European fishmeal. The NBFR levels are significantly lower compared to the polybrominated diphenyl ethers (PBDEs) (p < 0.01), indicating that the distribution of NBFRs was not as wide as PBDEs in fishmeal. DBDPE was significantly correlated with BDE209 (r = 0.557, p < 0.01), which implies that the two chemicals might have similar sources. Quantitative structure-activity relationship (QSAR)results imply that the NBFRs might have similar persistence and biomagnification potential as legacy lipophilic POPs.


Assuntos
Ração Animal/análise , Bromobenzenos/análise , Monitoramento Ambiental/métodos , Retardadores de Chama/análise , Contaminação de Alimentos/análise , Tolueno/análogos & derivados , Animais , China , Europa (Continente) , Cadeia Alimentar , Relação Quantitativa Estrutura-Atividade , América do Sul , Tolueno/análise
12.
Mikrochim Acta ; 186(7): 454, 2019 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-31201535

RESUMO

A metal organic framework (MOF) based adsorbent of type UiO-66 was hydrothermally prepared and applied to simultaneous sensing and removal of the asthma drug clenbuterol. The MOF possesses a large specific surface area (1460 cm2·g-1) and a stable structure, and has a large adsorption capacity for clenbuterol (160 mg·g-1). If clenbuterol binds to the MOF, the fluorescence of the sorbent (best measured at excitation/emission wavelengths of 290/396 nm) is quenched by up to 88%. Based on these findings, a fluorometric assay has been developed for the rapid determination of clenbuterol. The adsorption equilibrium of UiO-66 for CLB can be achieved at 60 min and the adsorption efficiency is above 80%. The method has a linear response in the 4.0 to 40 ng·mL-1 concentration range, and the lower limit of detection is 0.17 µM. All of this indicates that UiO-66 is promising for simultaneous detection and the removal of CLB in water. Graphical abstract Schematic presentation of the detection and removal of clenbuterol in water medium by a stable fluorescent Zr(IV)-based metal organic framework. This method exhibited a large adsorption capacity for clenbuterol (160 mg/g) and low limit of detection (0.17 µM).

13.
Molecules ; 24(3)2019 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-30696009

RESUMO

Biomarkers from methane hydrate-bearing sediments can provide vital evidence for microbial activities associated with methanogenesis and their relation to the formation of methane hydrates. However, the former mainly focus on intact polar lipids from these microorganisms, and rarely investigate molecular hydrocarbons such as acyclic isoprenoids and hopanes so far. In this work, the composition of biomarkers in the methane hydrate-bearing sediments in cores SH2B and SH7B from the Shenhu area, the South China Sea (SCS) were identified by gas chromatography-mass spectrometry (GC-MS) and comprehensive two-dimensional gas chromatography/time-of-flight mass spectrometry (GC×GC-TOFMS). The occurrence of unresolved complex mixtures (UCMs) and 25-norhopane indicate that the organic matters in methane hydrate-bearing sediments underwent a high degree of biodegradation. Although specific biomarkers for methanogens were not identified, the UCMs, 25-norhopane, pristane, phytane, and hopanes can still indicate the microbial activities associated with methanogenesis. These molecular signals suggest that diverse microorganisms, particularly methanogens, were quite vigorous in the methane hydrate-bearing sediments. Further, the biomarkers identified in this study can also be steadily detected from deep oil/gas reservoirs. Considering numerous adjacent oil/gas reservoir systems, fault systems, and mud diapers occurred in the SCS, it can be inferred that microbial activities and deep oil/gas reservoirs may have jointly contributed to the formation of methane hydrate deposits in the SCS.


Assuntos
Biomarcadores , Sedimentos Geológicos/análise , Sedimentos Geológicos/química , Metano/análise , China , Cromatografia Gasosa-Espectrometria de Massas , Geografia , Sedimentos Geológicos/microbiologia , Microbiota , Oceanos e Mares
14.
Protein Expr Purif ; 129: 9-17, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27576198

RESUMO

α-l-Fucosyl residues are frequently found in oligosaccharides, polysaccharides and glycoconjugates which play fundamental roles in various biological processes. α-l-Fucosidases, glycoside hydrolases for catalyzing the removal of α-l-fucose, can serve as desirable tools in the study and the modification of fucose-containing biomolecules. In this study, an α-l-fucosidase named as Alf1_Wf was purified from a marine bacterium Wenyingzhuangia fucanilytica by using a combination of chromatographic procedures. The sequence of Alf1_Wf was identified via proteomics analysis against the predicted proteome of the bacterium. Recombinant Alf1_Wf with 6×His tag was expressed in E. coli and showed α-l-fucosidase activity. Sequence annotation revealed that Alf1_Wf contained a combination of GH29 catalytic domain and CBM35 accessory domain. Alf1_Wf was confirmed as a member of GH29-A subfamily based on the phylogenetic analysis. Furthermore, biochemical properties and kinetic characteristics of the enzyme were also determined. Substrate specificity determination showed that Alf1_Wf was capable in hydrolyzing α1,4-fucosidic linkage and synthetic substrate pNP-fucose. Besides, Alf1_Wf could act on partially degraded fucoidan. This study successfully purified, identified, cloned, expressed and characterized a novel α-l-fucosidase, and meanwhile revealed a new multidomain structure of glycoside hydrolase. The knowledge gained from this study should facilitate the further research and application of α-l-fucosidases.


Assuntos
Organismos Aquáticos/genética , Proteínas de Bactérias , Escherichia coli/metabolismo , Flavobacteriaceae/genética , Expressão Gênica , alfa-L-Fucosidase , Organismos Aquáticos/enzimologia , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/isolamento & purificação , Escherichia coli/genética , Flavobacteriaceae/enzimologia , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , alfa-L-Fucosidase/biossíntese , alfa-L-Fucosidase/química , alfa-L-Fucosidase/genética , alfa-L-Fucosidase/isolamento & purificação
15.
Lasers Med Sci ; 32(7): 1489-1496, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28667508

RESUMO

Low-level laser could promote osteoblast proliferation, and it has been applied in clinical practice to promote wound healing and tissue regeneration. However, the mechanism related to laser irradiation remains unclear. This study aimed to investigate the effects of low-level laser irradiation on the cell proliferation and the expressions of hedgehog signaling molecules Indian hedgehog (Ihh), Ptch, and Gli in vitro. In our present study, the MTT method was used to evaluate the effect on cell proliferation of laser irradiation on MC3T3-E1 cells. And cell cycle was examined by flow cytometry. Gene and protein expressions of hedgehog signaling molecules, including Ihh, Ptch, Smoothened (Smo), and Gli, were examined by qRT-PCR and western blot analysis. The results showed that laser irradiation at dosage of 3.75 J/cm2 enhances the proliferation of MC3T3-E1 cells compared with control groups (p = 0.00). Moreover, laser irradiation (3.75 J/cm2) increased the cell amount at S phase (p = 0.00). In addition, the expressions of Ihh, Ptch, Smo, and Gli were significantly increased compared to the control during laser irradiation (3.75 J/cm2)-induced MC3T3-E1 osteoblast proliferation. After adding the hedgehog signaling inhibitor CY (cyclopamine), cell proliferation and Ihh, Ptch, Smo, and Gli expressions were inhibited (p = 0.00), and the cell amount at S phase was reduced compared with combination groups (p = 0.00). These results indicated that laser irradiation promotes proliferation of MC3T3-E1 cells through hedgehog signaling pathway. Our findings provide insights into the mechanistic link between laser irradiation-induced osteogenesis and hedgehog signaling pathway.


Assuntos
Proteínas Hedgehog/metabolismo , Lasers Semicondutores , Osteoblastos/citologia , Osteoblastos/efeitos da radiação , Transdução de Sinais/efeitos da radiação , Animais , Ciclo Celular/efeitos da radiação , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Proliferação de Células/efeitos da radiação , Regulação da Expressão Gênica/efeitos da radiação , Terapia com Luz de Baixa Intensidade , Camundongos , Osteogênese/efeitos dos fármacos , Osteogênese/genética , Osteogênese/efeitos da radiação , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Alcaloides de Veratrum/farmacologia
16.
Int J Syst Evol Microbiol ; 66(9): 3270-3275, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27220912

RESUMO

A Gram-staining-negative, rod-shaped, strictly aerobic, non-flagellated, non-gliding and yellow-pigmented bacterial strain, designated as strain CZ1127T, capable of utilizing sulfated fucan, was isolated from shallow coastal seawater of Jiaozhou Bay, Qingdao, PR China. Its taxonomic position was investigated by a polyphasic approach. CZ1127T grew at 15-37 °C (optimum, 25 °C), pH 5.5-9.0 (optimum, pH 6.5-7.5) and in the presence of 0-4 % (w/v) NaCl [optimum, 0-3 % (w/v)]. CZ1127T contained MK-6 as the sole menaquinone, and iso-C15 : 0, iso-C17 : 0 3-OH, C16 : 1ω7c/C16 : 1ω6c and iso-C15 : 0 3-OH as its major fatty acids. The DNA G+C content of strain CZ1127T was 32.2 mol%. Phylogenetic analysis based on the 16S rRNA gene indicated that strain CZ1127T clustered with members of the genus Wenyingzhuangia and was closely related to Wenyingzhuangia marina CGMCC 1.12162T (97.4 % 16S rRNA gene sequence similarity) and Wenyingzhuangia gracilariae KCTC 42246T (96.1 %). The DNA-DNA relatedness between strain CZ1127T and W. marina CGMCC 1.12162T was 41.9±1.5 %. On the basis of the phenotypic, chemotaxonomic and phylogenetic data, CZ1127T represents a novel species of the genus Wenyingzhuangia, for which the name Wenyingzhuangia fucanilytica sp. nov. is proposed. The type strain is CZ1127T (=CCTCC AB 2015089T=KCTC 42864T).


Assuntos
Flavobacteriaceae/classificação , Filogenia , Polissacarídeos/metabolismo , Água do Mar/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Flavobacteriaceae/genética , Flavobacteriaceae/isolamento & purificação , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
17.
Proteomics ; 14(20): 2335-8, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25047511

RESUMO

Inositol 1,4,5-trisphosohate (IP3 ) and its receptors play a pivotal role in calcium signal transduction in mammals. However, no homologs of mammalian IP3 receptors have been found in plants. In this study, we isolated the microsomal fractions from rice cells in suspension culture and further obtained putative IP3 -binding proteins by heparin-agarose affinity purification. The IP3 -binding activities of these protein fractions were determined by [(3) H] IP3 -binding assay. SDS-PAGE and MS analysis were then performed to characterize these proteins. We have identified 297 proteins from the eluates of heparin-agarose column chromatography, which will provide insight into the IP3 signaling pathways in plants. All MS data have been deposited in the ProteomeXchange with identifier PXD000763 (http://proteomecentral.proteomexchange.org/dataset/PXD000763).


Assuntos
Marcadores de Afinidade/metabolismo , Inositol 1,4,5-Trifosfato/metabolismo , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Sefarose/análogos & derivados , Eletroforese em Gel de Poliacrilamida , Espectrometria de Massas , Proteínas de Plantas/isolamento & purificação , Proteômica , Sefarose/metabolismo , Transdução de Sinais
18.
J Econ Entomol ; 107(2): 601-5, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24772539

RESUMO

Bactrocera tau (Walker) is one of the most harmful pests to fruits and vegetables. To counteract this pest, the development of phytosanitary treatment is required to comply with the pest regulation requirements of certain countries. This study investigated the toxicity of phosphine fumigation against B. tau under low temperature conditions. Different growth stages (eggs and instars) of B. tau were exposed to 1.07 mg/liter phosphine for 1-10 d at 5 degrees C, and compared with unfumigated flies at 5 degrees C. The results showed that tolerance to cold treatment alone or phosphine fumigation at low temperatures generally increased with the stage of insect development. However, eggs incubated for 12 h at 25 degrees C represented the most tolerant growth stage to phosphine fumigation at 5 degrees C. Furthermore, 8.56- to 2.18-d exposure periods were required to achieve 99% mortality with a range of phosphine concentrations from 0.46 to 3.81 mg/liter. C0.62 t = k expression was obtained from the LT99 values, indicating that the exposure time was more important than the phosphine concentration.


Assuntos
Controle de Insetos/métodos , Inseticidas/farmacologia , Fosfinas/farmacologia , Tephritidae/efeitos dos fármacos , Animais , Temperatura Baixa , Fumigação , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Dose Letal Mediana , Óvulo/efeitos dos fármacos , Tephritidae/crescimento & desenvolvimento
19.
Front Bioeng Biotechnol ; 12: 1411494, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38827033

RESUMO

Periodontal defects involve the damage and loss of periodontal tissue, primarily caused by periodontitis. This inflammatory disease, resulting from various factors, can lead to irreversible harm to the tissues supporting the teeth if not treated effectively, potentially resulting in tooth loss or loosening. Such outcomes significantly impact a patient's facial appearance and their ability to eat and speak. Current clinical treatments for periodontitis, including surgery, root planing, and various types of curettage, as well as local antibiotic injections, aim to mitigate symptoms and halt disease progression. However, these methods fall short of fully restoring the original structure and functionality of the affected tissue, due to the complex and deep structure of periodontal pockets and the intricate nature of the supporting tissue. To overcome these limitations, numerous biomaterials have been explored for periodontal tissue regeneration, with hydrogels being particularly noteworthy. Hydrogels are favored in research for their exceptional absorption capacity, biodegradability, and tunable mechanical properties. They have shown promise as barrier membranes, scaffolds, carriers for cell transplantation and drug delivery systems in periodontal regeneration therapy. The review concludes by discussing the ongoing challenges and future prospects for hydrogel applications in periodontal treatment.

20.
Sci Adv ; 10(22): eadk1894, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38820153

RESUMO

Antibody drug conjugates (ADCs) have made impressive strides in the clinic in recent years with 11 Food and Drug Administration approvals, including 6 for the treatment of patients with solid tumors. Despite this success, the development of new agents remains challenging with a high failure rate in the clinic. Here, we show that current approved ADCs for the treatment of patients with solid tumors can all show substantial efficacy in some mouse models when administered at a similar weight-based [milligrams per kilogram (mg/kg)] dosing in mice that is tolerated in the clinic. Mechanistically, equivalent mg/kg dosing results in a similar drug concentration in the tumor and a similar tissue penetration into the tumor due to the unique delivery features of ADCs. Combined with computational approaches, which can account for the complex distribution within the tumor microenvironment, these scaling concepts may aid in the evaluation of new agents and help design therapeutics with maximum clinical efficacy.


Assuntos
Imunoconjugados , Neoplasias , Animais , Imunoconjugados/administração & dosagem , Imunoconjugados/farmacocinética , Imunoconjugados/farmacologia , Camundongos , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Humanos , Ensaios Antitumorais Modelo de Xenoenxerto , Pesquisa Translacional Biomédica , Modelos Animais de Doenças , Microambiente Tumoral/efeitos dos fármacos , Linhagem Celular Tumoral , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacocinética , Avaliação Pré-Clínica de Medicamentos
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