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1.
Chemosphere ; 239: 124811, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31726522

RESUMO

China has been suffering from endemic fluorosis for the past 30 years. This study investigated fluoride concentrations in 10 districts of Tianjin, China, to illustrate their spatial distribution characteristics and potential human health risks. The results showed fluoride concentration of 0.01-6.30 mg L-1 with a mean value of 0.99 mg L-1, and 78.82% of water fluoride reaches the standard for drinking water (1.5 mg L-1). Higher fluoride levels were recorded in deep well pumps supply zones, and more potential changes in fluoride occurred was positively correlated with pH in groundwater. Mean value of fluoride in drinking water in 10 districts followed the order of WQ > BC > JZ > NH > BD > BH > JN > JH > DL > XQ. Estimations of non-carcinogenic risk for drinking water indicated that mean hazard quotient values of fluoride for combined pathways (i.e., oral ingestion and dermal absorption) were >1.0 for all age groups of WQ and BC. The results also showed that the estimated risk primarily came from the ingestion pathway. Risk levels for children varied obviously, generally in the order of 1-4y > 4-7y > 7-9y (years old). In the central tendency center and reasonable maximum exposure conditions, estimated risks were 1.25, 1.12, 0.771 and 3.66, 3.29, 2.27, respectively. The results supply material information for health authorities in fluorosis areas to put forward more efficient policies to control the endemic diseases. Attention should be paid to the formulation of health promotion strategies and measures to reduce fluoride intake in order to protect the health of residents.

2.
Environ Sci Technol ; 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31692337

RESUMO

Widespread iron-bearing clay minerals are potential materials that can reduce and immobilize Cr(VI) as insoluble Cr2O3/Cr(OH)3. The kinetics of this process is controlled by various environmental factors, yet the effects of such factors on the Cr(VI) transformation by iron-bearing clays are poorly understood. Herein we report the synergistic effects of reduced nontronite (rNAu-2) and environmentally prevalent organic ligands on Cr(VI) reduction under near-neutral pH condition. The presence of ligands belonging to α-hydroxyl or carbonyl carboxylates, such as tartrate, malate, lactate, pyruvate, and mandelate, significantly promoted the rate and extent of Cr(VI) reduction by rNAu-2, likely because of the formation of Cr(V)-ligand complexes and resulting electron transfer from ligand to Cr(V). In contrast, ligands containing carboxyl groups only, such as succinate and propionate, had a slightly inhibitory or no effect, likely because of their weak complexing ability with Cr(V) and no electron transfer from ligand to Cr(V). In addition, α-hydroxyl carboxylates are probably more easily oxidized by Cr(V)/Cr(IV) than carboxylates. Soluble Cr(III)-organic complexes were the dominant products of Cr(VI) reduction in the presence of tartrate and malate. This study highlights the importance of organic ligands in the biogeochemical cycling of chromium and has significant implications for chromium remediation in contaminated environments.

3.
J Hazard Mater ; : 121431, 2019 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-31672436

RESUMO

Spermatogenesis-related microRNAs (miRNAs) are vulnerable to polycyclic aromatic hydrocarbons (PAHs). Changes in spermatogenesis-related miRNAs may be biological intermedia in mechanisms linking PAHs and semen quality. This study aimed to investigate whether spermatogenesis-related microRNAs mediate the associations between PAHs and semen quality. We measured 10 monohydroxylated PAHs (OH-PAHs) in repeated urine samples and three candidate spermatogenesis-related miRNAs (miRNA106a, miRNA21, and miRNA34c) in seminal plasma from men attending an infertility clinic (n = 111). Mediation analysis was applied to determine the mediating role of spermatogenesis-related miRNAs in the association of PAH exposure with semen quality. Urinary 2-OHFlu and 2-OHPh were related to reduced seminal plasma miRNA34c (p for trend = 0.05 and 0.03, respectively). Urinary 9-OHPh was related to reduced seminal plasma miR106a (p for trend = 0.02), which in turn, was positively associated with sperm concentration, sperm count, sperm total motility, and progressive motility (all p for trends<0.05). Up to 43.8% of the eff ;ect of urinary 9-OHPh on decreased sperm concentration was mediated by seminal plasma miR106a. Our results suggested that certain PAH exposure was associated with reduced spermatogenesis-related miRNAs and such alterations might be an intermediate mechanism by which PAHs exert its adverse effects on semen quality.

4.
BMC Public Health ; 19(1): 1465, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31694683

RESUMO

BACKGROUND: Ischemic heart disease (IHD) is one of the leading causes of deaths worldwide and causes a tremendous disease burden. Temperature is an important environmental determinant among the many risk factors for IHD. However, the emerging temperature-related health risks of IHD in the elderly is limited because of the lack of estimates that integrate global warming and demographic change. METHODS: Data on daily IHD deaths in the elderly aged ≥65 years and meteorological conditions were collected in Tianjin, a megacity of China, from 2006 to 2011. First, the baseline relationship between the temperature and years of life lost (YLL) from IHD was established. Then, future assessments were performed in combination with temperature projections for 19 global-scale climate models (GCMs) under 3 representative concentration pathways (RCPs) for the 2050s and 2070s. RESULTS: Increased YLL from IHD in the elderly was found to be associated with future ambient temperatures. The annual temperature-related YLL from IHD in the 2050s and 2070s were higher than the baseline. For instance, increases of 4.5, 14.9 and 38.3% were found under the RCP2.6, RCP4.5 and RCP8.5 scenarios, respectively, in the 2070s. The most significant increases occurred in warm season months. The increase in heat-related YLL will not be completely offset, even with the 25% adaptation assumed. When considering demographic change, the temperature-related disease burden of IHD in the elderly will be exacerbated by 158.4 to 196.6% under 3 RCPs in the 2050s and 2070s relative to the baseline. CONCLUSIONS: These findings have significant meaning for environmental and public health policy making and interventions towards the important issue of the health impacts of global warming on the elderly.

5.
ACS Nano ; 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31697072

RESUMO

Plasmonic microscopy is a powerful tool for nanoscopic bio- and chemical sample analysis due to its high sensitivity. Phase quantification in plasmonic microscopy would provide inherent information, i.e., refractive index, for identification of nanomaterials. However, it usually relies on complex optics to acquire quantitative phase images. Here, we demonstrated the quantitative amplitude and phase imaging capabilities through holographical reconstructions of the plasmonic patterns recorded in the interferometric plasmonic microscopy. Operating the plasmonic microscopy over the surface plasmon resonance angle separates the twin images and allows for accurate mapping of the amplitude and phase distribution of surface plasmon near fields. Results show that the imaging capabilities enable direct visualization of complex surface plasmon fields arising from interactions with nanoparticles and nanowires, without the need for nanoscopic scanning probes. Theoretical and experimental analysis also suggests future applications in the identification of nanoparticles and super-resolution imaging. The proposed technology is thus promising for nanoplasmonic study and various sensing purposes.

6.
Environ Int ; 134: 105229, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31698198

RESUMO

BACKGROUND: Thyroid hormones (THs) are critical for brain development. Whether low-moderate fluoride exposure affects thyroid function and what the impact is on children's intelligence remain elusive. OBJECTIVES: We conducted a cross-sectional study to examine the associations between low-moderate fluoride exposure and thyroid function in relation to children's intelligence. METHODS: We recruited 571 resident children, aged 7-13 years, randomly from endemic and non-endemic fluorosis areas in Tianjin, China. We measured fluoride concentrations in drinking water and urine using the national standardized ion selective electrode method. Thyroid function was evaluated through the measurements of basal THs [(total triiodothyronine (TT3), total thyronine (TT4), free triiodothyronine (FT3), free thyronine (FT4)] and thyroid-stimulating hormone (TSH) levels in serum. Multivariable linear and logistical regression models were used to assess associations among fluoride exposure, thyroid function and IQ scores. RESULTS: In adjusted models, every 1 mg/L increment of water fluoride was associated with 0.13 uIU/mL increase in TSH. Every 1 mg/L increment of urinary fluoride was associated with 0.09 ug/dL decrease in TT4, 0.009 ng/dL decrease in FT4 and 0.11 uIU/mL increase in TSH. Fluoride exposure was inversely related to IQ scores (B = -1.587; 95% CI: -2.607, -0.568 for water fluoride and B = -1.214; 95% CI: -1.987, -0.442 for urinary fluoride). Higher TT3, FT3 were related to the increased odds of children having high normal intelligence (OR = 3.407, 95% CI: 1.044, 11.120 for TT3; OR = 3.277, 95% CI: 1.621, 6.623 for FT3). We detected a significant modification effect by TSH on the association between urinary fluoride and IQ scores, without mediation by THs. CONCLUSIONS: Our study suggests low-moderate fluoride exposure is associated with alterations in childhood thyroid function that may modify the association between fluoride and intelligence.

7.
Environ Int ; 134: 105282, 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31711017

RESUMO

BACKGROUND: Experimental studies have demonstrated that cadmium exposure induces alterations on immune function, but epidemiological evidence is lacking. OBJECTIVE: To examine the associations between prenatal and postnatal cadmium exposure and cellular immune responses among pre-school children. METHODS: Pre-school aged children (n = 407) were followed from a prospective birth cohort study in Wuhan, China. Maternal urinary and children's plasma cadmium concentrations were measured as biomarkers of prenatal and postnatal cadmium exposure, respectively. Children's cellular immune responses were assessed by peripheral blood T lymphocyte subsets and plasma cytokines. Multivariable adjusted models were applied to estimate the associations of prenatal and postnatal cadmium exposure with T lymphocyte subsets and cytokines, and the effect modification by child gender were also examined. RESULTS: Maternal urinary cadmium was associated with reduced absolute counts of CD3+CD4+ cells (-12.45%; 95% CI: -23.74%, 0.40% for the highest vs. lowest quartile; p for trend = 0.045). Inverse associations of maternal urinary cadmium with %CD3+CD4+ cells and CD4+/CD8+ ratio were only observed among females (both p-interaction < 0.050); whereas an inverse association with absolute counts of CD3+CD8+ cells was only observed among males (p-interaction = 0.057). Positive associations of maternal urinary cadmium with %CD3+CD4+ cells, interleukin-4 (IL-4), and IL-6 were only observed among females, although there were no significant interactions. We observed no clear associations of children's plasma cadmium with T lymphocyte subsets and cytokines. CONCLUSION: Prenatal but not postnatal cadmium exposure was associated with sex-specific alterations on children's cellular immune responses.

8.
Medicine (Baltimore) ; 98(46): e17949, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31725652

RESUMO

Recently, we have proposed a theoretical modified tri-exponential model for multi-b-value diffusion-weighted imaging (DWI) to measure the cytoplasmic organelle water fraction (COWF). This study aims to investigate whether COWF maps are effective in evaluating the malignant degree of gliomas and distinguishing primary central nervous system lymphomas (PCNSL) from gliomas.We performed this retrospective study based on our prospectively collected data. All patients underwent preoperative multi-b-value DWI. Parametric maps were derived from multi-b-value DWI maps using the modified tri-exponential model. Receiver operating characteristic analyses were used to assess the diagnostic accuracy of the parameter maps. Pearson correlation coefficients were calculated to investigate the correlations between the parameters and the Ki-67 proliferation index.A total of 66 patients were enrolled, including 16 low-grade gliomas (LGG), 45 high-grade gliomas (HGG), and 5 PCNSL. The mean COWF values were significantly different among LGG (3.1 ±â€Š1.4%), HGG (6.9 ±â€Š2.8%), and PCNSL (14.0 ±â€Š2.2%) (P < .001). The areas under the curves of the mean COWF value in distinguishing HGG from LGG and distinguishing PCNSL from gliomas were 0.899 and 0.980, respectively. The mean COWF value had a moderate correlation with the Ki-67 proliferation index (r = 0.647).The COWF map is useful in malignant grading of gliomas, and may be helpful in distinguishing PCNSL from gliomas.

9.
Artigo em Inglês | MEDLINE | ID: mdl-31722435

RESUMO

OBJECTIVES: aCL and anti-ß2 glycoprotein I antibody (aß2GPI) are autoantibodies associated with thromboembolic diseases. Here we investigated whether they are correlated with ischaemic cardiovascular disease in a Chinese population. METHODS: Serum total aCL and aß2GPI isotypes (IgA, IgG or IgM, separately) were measured in 11 015 Chinese adults. Differences of antibody level between disease and non-disease groups were examined by t-test. The correlation between antibody and ischaemic cardiovascular disease was determined by logistic regression analysis. Performance of risk prediction models employed aCL or aß2GPI isotypes was evaluated by C statistic, net reclassification improvement index and integrated discrimination improvement. RESULTS: Total aCL and aß2GPI isotypes maintained low levels and increased with increasing age except total aCL and aß2GPI IgG in participants older than 70 years. When distinguishing ischaemic cardiovascular disease by coronary heart disease (CHD) and ischaemic stroke, the stroke group had higher levels of aCL and aß2GPI isotypes than the non-stroke group, while the CHD group only had a slightly higher aß2GPI IgG than non-CHD groups. aCL and aß2GPI were positively correlated with stroke but not with CHD, and improved the performance of conventional risk factors for stroke risk prediction, with C statistic from 0.769 (95% CI 0.744, 0.793) to 0.777 (95% CI 0.754, 0.800) (aß2GPI IgG, P = 0.0091), and 0.778 (95% CI 0.754, 0.801) (aß2GPI IgA, P = 0.0793). Stroke risk could be better reclassified by aCL and aß2GPI, in association with both net reclassification improvement and integrated discrimination improvement statistics (P < 0.05). CONCLUSION: aCL and aß2GPI are associated with ischaemic stroke and have added value for stroke risk prediction.

10.
Ann Hematol ; 98(11): 2523-2531, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31637485

RESUMO

The use of hypomethylating agents (HMAs) prior to hematopoietic stem cell transplantation (HSCT) in patients with myelodysplastic syndromes (MDS) was still controversial. Therefore, we sought to evaluate the impact of hypomethylation therapy before HSCT, with a special focus on long-term outcome. Databases, including PubMed, Embase Ovid, and the Cochrane Library, were searched for studies published up to 4 November 2018. Overall survival (OS) was selected as the primary endpoint, and relapse-free survival (RFS) was the secondary endpoint. A total of 6 cohort studies were included in the final meta-analysis. Our results showed that the outcome of patients with MDS using HMAs prior to HSCT was similar compared to those who did not with OS (HR = 0.81, 95% CI 0.63-1.04, p = 0.104) and RFS (HR = 0.96, 95% CI 0.72-1.26, p = 0.749). The pooled HR of OS in the older patients was 0.75 (95% CI 0.57-0.98, p = 0.035). No evidence showed that patients with MDS will benefit from using HMAs before HSCT in long-term survival (OS and RFS) compared to chemotherapy or best supportive therapy, though older patients were more likely to benefit from pre-transplantation HMAs treatment in terms of long-term survival. Our conclusions await further validation by prospective studies with larger sample size and randomized-controlled design. Particularly, to clarify whether the older patients who are candidates for HSCT could benefit from this bridging treatment will be of great interest.

11.
Ecotoxicol Environ Saf ; 183: 109558, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31509932

RESUMO

High fluoride exposure has been related to harmful health effects, but the impacts of low-to-moderate fluoride on child growth and obesity-related outcomes remain unclear. We performed a large-scale cross-sectional study to examine the association between low-to-moderate fluoride in drinking water and anthropometric measures among Chinese school-age children. We recruited 2430 resident children 7-13 years of age, randomly from low-to-moderate fluorosis areas of Baodi District in Tianjin, China. We analyzed the fluoride contents in drinking water and urine samples using the national standardized ion selective electrode method. Multivariable linear and logistic analyses were used to assess the relationships between fluoride exposure and age- and sex-standardized height, weight and body mass index (BMI) z-scores, and childhood overweight/obesity (BMI z-score > 1). In adjusted models, each log unit (roughly 10-fold) increase in urinary fluoride concentration was associated with a 0.136 unit increase in weight z-score (95% CI: 0.039, 0.233), a 0.186 unit increase in BMI z-score (95% CI: 0.058, 0.314), and a 1.304-fold increased odds of overweight/obesity (95% CI: 1.062, 1.602). These associations were stronger in girls than in boys (Pinteraction = 0.016), and children of fathers with lower education levels were more vulnerable to fluoride (Pinteraction = 0.056). Each log unit (roughly 10-fold) increase in water fluoride concentration was associated with a 0.129 unit increase in height z-score (95% CI: 0.005, 0.254), but not with other anthropometric measures. Our results suggest low-to-moderate fluoride exposure is associated with overweight and obesity in children. Gender and paternal education level may modify the relationship.

12.
Biomed Pharmacother ; 118: 109306, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31545250

RESUMO

BACKGROUND: Notch1 expression has been reported to be associated with chemotherapy resistance and poor prognosis, but the role of Notch1 in head and neck squamous cell carcinoma (HNSCC) sensitivity to anticancer drugs remains unclear. The aim of this study was to evaluate HNSCC sensitivity to paclitaxel and cisplatin in vitro and the chemotherapeutic response of HNSCC to these two drugs in vivo. METHODS: We used immunohistochemistry to assess Notch1 expression in fresh HNSCC samples treated by PF (cisplatin+5- fluorouracil) and TPF (paclitaxel + cisplatin+5- fluorouracil). We also assessed the sensitivity of two HNSCC cell lines to the Notch1 inhibitor of N-[N-(3,5-difluorophenacetyl)-L-alanyl]-S-phenylglycine t-butyl ester (DAPT). The overall and progression-free survival were assessed. RESULTS: High Notch1 expression was significantly associated with paclitaxel resistance (P < 0.01). DAPT increased sensitivity to paclitaxel and cisplatin in vitro (P < 0.05). Compared with patients with Notch1 expression, patients without Notch1 expression were more likely to have a response to neoadjuvant chemotherapy with PF (P < 0.01) or TPF (P < 0.01) and had significantly better overall survival (P < 0.05) and progression-free survival (P < 0.05). Among patients without Notch1 expression (but not among patients with Notch1 expression), those who received TPF had significantly better survival than those who received PF (P < 0.05). CONCLUSION: Taken together, our findings may provide some evidence to partially support the predictive value of Notch1 expression in the therapeutic response to paclitaxel and cisplatin.

13.
ISA Trans ; 2019 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-31558284

RESUMO

In this paper, fully distributed containment control problems of multi-agent systems with double-integrator dynamics are investigated under directed topologies. For the cases with and without communication delay, two new fully distributed control protocols are designed, which do not need any global information of the communication topology graph. Necessary and sufficient conditions are obtained to ensure the solvability of the considered containment control problems. Particularly, for the case with communication delay, the critical value of the maximum allowable time delay of containment control is found. Finally, numerical simulations are presented to demonstrate the effectiveness of the theoretical results.

14.
Sci Rep ; 9(1): 13424, 2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31530820

RESUMO

The gut microbiota (GM) is related to obesity and other metabolic diseases. To detect GM markers for obesity in patients with different metabolic abnormalities and investigate their relationships with clinical indicators, 1,914 Chinese adults were enrolled for 16S rRNA gene sequencing in this retrospective study. Based on GM composition, Random forest classifiers were constructed to screen the obesity patients with (Group OA) or without metabolic diseases (Group O) from healthy individuals (Group H), and high accuracies were observed for the discrimination of Group O and Group OA (areas under the receiver operating curve (AUC) equal to 0.68 and 0.76, respectively). Furthermore, six GM markers were shared by obesity patients with various metabolic disorders (Bacteroides, Parabacteroides, Blautia, Alistipes, Romboutsia and Roseburia). As for the discrimination with Group O, Group OA exhibited low accuracy (AUC = 0.57). Nonetheless, GM classifications to distinguish between Group O and the obese patients with specific metabolic abnormalities were not accurate (AUC values from 0.59 to 0.66). Common biomarkers were identified for the obesity patients with high uric acid, high serum lipids and high blood pressure, such as Clostridium XIVa, Bacteroides and Roseburia. A total of 20 genera were associated with multiple significant clinical indicators. For example, Blautia, Romboutsia, Ruminococcus2, Clostridium sensu stricto and Dorea were positively correlated with indicators of bodyweight (including waistline and body mass index) and serum lipids (including low density lipoprotein, triglyceride and total cholesterol). In contrast, the aforementioned clinical indicators were negatively associated with Bacteroides, Roseburia, Butyricicoccus, Alistipes, Parasutterella, Parabacteroides and Clostridium IV. Generally, these biomarkers hold the potential to predict obesity-related metabolic abnormalities, and interventions based on these biomarkers might be beneficial to weight loss and metabolic risk improvement.

15.
Analyst ; 144(20): 6118-6127, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31532402

RESUMO

In this work, a sensing nanochannel based on a N-[3-(triethoxysilyl)propyl]-4,5-dihydroimidazole (DHI) modified nanopipette was prepared and characterized for the ultrasensitive detection of cobalt ions (Co2+) in aqueous solutions. By both experimental and theoretical studies, the detection conditions (chelation balance time, pH of the electrolyte, nanopipette diameter, potentials for ionic current) and parameters (rectification value, resistance and ionic current) have been fully optimized, and the proposed Co2+ sensor shows a significantly wide detection range from 20 fM to 0.2 mM, with an ultra-low detection limit down to 0.94 fM.

16.
J Hazard Mater ; 383: 121189, 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31541958

RESUMO

Phthalates have been reported to affect the function and growth of thyroid. However, there is little data on the effect of phthalates on thyroid oncogenesis. Here we explored the associations between phthalates exposure and the risks of thyroid cancer and benign nodule. We sex-matched 144 thyroid cancer, 138 benign nodule patients and 144 healthy adults from Wuhan, China. Eight phthalate metabolites in spot urine samples were quantified using high-performance liquid chromatography and tandem mass spectrometry. The associations of creatinine-corrected urinary phthalate metabolites with the risks of thyroid cancer and benign nodule were assessed using multivariable logistic regression models. We found that urinary monomethyl phthalate (MMP), mono(2-ethyl-5hydroxyhexyl) phthalate (MEHHP) and mono(2-ethylhexyl) phthalate (MEHP) associated with increased risks of thyroid cancer and nodule, with adjusted odds ratios (ORs) ranging from 1.74 to 4.78 comparing the extreme tertiles, and urinary monobutyl phthalate (MBP) was associated with decreased risks of thyroid cancer and benign nodule (all P for trends < 0.05). Male-specific positive associations of urinary monoethyl phthalate (MEP) with thyroid cancer and nodule as well as urinary mono(2-ethyl-5-oxohexyl) phthalate (MEOHP) with thyroid cancer were also observed. Our results suggest that exposure to certain phthalates may contribute to increased risks of thyroid cancer and benign nodule.

17.
J Hazard Mater ; 383: 121199, 2019 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-31541962

RESUMO

Preparing a cost-effective material which can been applied in a wide pH range is very crucial for the remediation of Cr(Ⅵ) polluted water. In this study, a novel material, almandine/humboldtine nanospheres (AHN) composites, was synthesized directly from almandine by one-pot method. Characterizations of XRD and SEM/TEM showed that the structure changes of almandine to nano-humboldtine leaded to significant increase of Cr(Ⅵ) removal capacities. And 96.45% of Cr(Ⅵ) was removed by AHN-24 composite at pH value of 3, initial Cr(Ⅵ) concentration of 20 mg/L, temperature of 298.15 K and dosage of 0.6 g/L. Furthermore, Cr(Ⅵ) removal capacity was only decreased from 48.23 mg/g to 34.33 mg/g when the initial pH value increased from 3 to 11, which demonstrated that the synthesized composite had a wide pH application range in Cr(Ⅵ) removal. The thermodynamic parameters (ΔG0 < 0, ΔH0 > 0 and ΔS0 > 0) illustrated that Cr(VI) removal process was spontaneous and endothermic. FTIR and XPS revealed that the Cr(Ⅵ) removal mechanisms included reduction-precipitation and reduction-complexation. Combined with cost analysis, all of results implied that the synthesized composites were a high efficient and low cost material for Cr(Ⅵ) pollution remediation in a wide pH range.

18.
ACS Appl Mater Interfaces ; 11(40): 36449-36457, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31532178

RESUMO

Multifunctional antibacterial materials have great significance for treating biomedical device-associated infections (BAIs). In the present work, a facile and rational strategy was developed to produce dual-functional implants with antibacterial and osteointegration-promoting properties for the treatment of BAI. A titanium implant, as a representative demo of implants, was first functionalized with ethanediamine-functionalized poly(glycidyl methacrylate) (PGED) brushes. Then, low-molecular-weight quaternized polyethyleneimine (QPEI, a cationic antibacterial agent) and alendronate (ALN, a clinically used drug with high affinity for bone minerals) were covalently conjugated onto PGED brushes to produce dual-functional dental implants (Ti-AQ). The QPEI component imparted Ti-AQ with antibacterial abilities, and the ALN component could balance the cytotoxicity of a cationic antibacterial agent, improving the biocompatibility for osteoblast cells. The effective performances of anti-infection and osteointegration were demonstrated in a BAI animal model. The results indicated that Ti-AQ inhibited bacterial infection at the early stage and enhanced the osteointegration and biomechanical properties between the implants and bone tissues at the late stage. This study will provide one facile and universal strategy for the design and development of novel multifunctional antibacterial implants.

19.
Environ Sci Technol ; 53(20): 12026-12034, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31525872

RESUMO

The effects of disinfection byproducts (DBPs) on adverse birth outcomes remain unsettled. Maternal genetic variants in relation to DBP metabolism may modify this effect. Pregnant women during late pregnancy (n = 1306) were included from a Chinese cohort. Maternal urinary trichloroacetic acid (TCAA) was measured as a biomarker of DBP exposure. Maternal genotyping was conducted in cytochrome P450 2E1 (CYP2E1; rs2031920, rs3813867, and rs915906) and glutathione S-transferase zeta-1 (GSTZ1; rs7975). The associations between maternal urinary TCAA and birth outcomes and statistical interactions between maternal exposure and genetic polymorphisms were estimated. We found that maternal urinary TCAA levels were associated with decreased birth weight (P for trend = 0.003) and ponderal index (P for trend = 0.004). Interaction analyses showed that maternal urinary TCAA in association with decreased birth weight was observed only among subjects with CYP2E1 rs3813867 GC/CC versus GG (Pint = 0.07) and associations with decreased birth length, ponderal index, and gestational age were observed only among subjects with GSTZ1 rs7975 GA/AA versus GG (Pint = 0.07, 0.02, and 0.02, respectively). Our results suggested that prenatal DBP exposure was negatively associated with birth weight and ponderal index, and maternal genetic polymorphisms in CYP2E1 and GSTZ1 might modify these associations.

20.
Chin J Dent Res ; 22(3): 165-173, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31508604

RESUMO

OBJECTIVE: To investigate the changes of the bacterial community in the oral environment of beagle dogs to gain insights on the possible causes of failed therapy in peri-implantitis. METHODS: Beagles were used as models for experimental peri-implantitis. Samples from peri-implant soft tissue (supramargin and submargin), ligature and contaminated surface of peri-implantitis sites were collected and analysed by sequencing the bacterial 16S rRNA gene. RESULTS: The residual microbial community from the curettes-treated implant surface contained a variety of microorganisms, including periodontal pathogens, which showed no changes in their composition and structure. CONCLUSION: It is possible that the residual bacterial community remained unchanged and this was the cause of recurrent episodes of inflammation.


Assuntos
Implantes Dentários , Microbiota , Peri-Implantite , Animais , Bactérias , Cães , RNA Ribossômico 16S
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