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1.
J Nanosci Nanotechnol ; 20(2): 719-730, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31383067

RESUMO

The efficient removal of toxic metal ions from waste water is of critical importance in environmental protection. In this study, we report the incorporation of graphene oxide (GO) into bacterial cellulose (BC) and the effect on the removal of metal ions from waste water. The as-prepared BC/GO adsorbents have a three-dimensional (3D) network structure with interconnected pores and high porosity. The adsorption capacities and efficiencies of the BC/GO adsorbents with varying GO contents were compared by using Cu2+, Cd2+, and Pb2+ as model heavy metal ions. The incorporated GO into the BC/GO adsorbents plays a critical role in removing metal ions through strong electrostatic interactions between the positive metal ions and the negative functional groups on GO. In addition, the effects of pH, contact time, adsorbent dose, and ion concentration on the adsorption behavior of the BC/GO adsorbents were investigated. The data from adsorption kinetics indicate that the adsorption of Cu2+, Cd2+, and Pb2+ on BC/GO obeys a pseudo-second-order model, while the adsorption isotherms vary with the type of metal ions. The desorption and readsorption experiments of the BC/GO adsorbents demonstrate good recyclability. It has been demonstrated that incorporating GO into BC is an effective way to improve the adsorption behavior of BC.

2.
Mol Cell Endocrinol ; 499: 110608, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31586455

RESUMO

Previously we had identified adamts9 as a downstream target of Pgr, which is essential for ovulation in zebrafish. The primary goal of this study is to determine whether human chorionic gonadotropin (hCG, LH analog) also regulate adamts9 expression prior to ovulation. The expression of adamts9 was induced by hCG in a dose and time dependent manner in zebrafish preovulatory follicles in vitro. Interestingly, the stimulatory effect of hCG on adamts9 expression was not blocked in pgr-/- follicles but blocked in lhcgr-/-. This effect of hCG was via Lhcgr and its associated cAMP and PKC signaling pathways. Reduced fecundity and reduced expression of adamts9 were also found in lhcgr-/- females in vivo. Therefore, we have provided the first evidence of gonadotropin (hCG) regulated adamts9 in zebrafish, which could be important for ovulation.

3.
J Pharm Biomed Anal ; 177: 112850, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31499430

RESUMO

In the present study, an accurate and sensitive ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method for the determination of plasma talazoparib concentration in rats was developed and established. The purpose of chromatographic separation of talazoparib and the internal standard (bosutinib) was achieved on an Acquity BEH C18 (2.1 mm × 50 mm, 1.7 µm) column with a flow rate of 0.40 mL/min, using a gradient elution with acetonitrile and 0.1% formic acid in water as the mobile phase. The detection was performed on a XEVO TQ-S triple quadrupole tandem mass spectrometer coupled with electrospray ionization interface under positive-ion multiple reaction monitoring (MRM) mode with the precursor-to-product ion transitions of m/z 381.3 → 285.2 for talazoparib and m/z 530.2 → 141.2 for bosutinib (IS), respectively. The method was linear over the range of 0.5-200 ng/mL for talazoparib. The accuracies and precisions of intra- and inter-day were all within the acceptance limits, and no matrix effect was observed in this method. The validated method was further employed to a pharmacokinetic study of talazoparib after oral treatment with 0.2 mg/kg talazoparib to rats.

4.
J Hazard Mater ; 383: 121160, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31518812

RESUMO

The application of current soil quality standards based on total arsenic (As) fails to assess the ecological risks of soil arsenic or to ensure the safety of crops and foods. In this study, bioavailable arsenic instead of total arsenic was applied to improve predictive models for arsenic transfer from soil to wheat (Triticum turgidum L.). The stepwise multiple-linear regression analysis showed that bioavailable arsenic and amorphous iron oxides (FeOX) were the two most important factors contributing to arsenic accumulation in wheat grain, with the explained percentage of variation being up to 82%. Compared with the bioavailable arsenic extracted by NH4H2PO4, bioavailable arsenic extracted by HNO3 from soils generated better predictions of the amount of arsenic in grain. The best reliable model was log[Asgrain] = 0.917 log[HNO3-As] - 0.452 log[FeOX] - 1.507 (R2 = 0.82, P <  0.001). Consistently, bioavailable arsenic and FeOX were also the key factors to predict arsenic accumulation in wheat straw, leaves and spikes. Our prediction models was successfully verified for three independent soils. Our results highlight the role of soil bioavailable heavy metals in predicting their transfer in soil-plant systems and can be used to improve existing Chinese soil quality standards.

5.
Environ Sci Technol ; 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31682413

RESUMO

Massive amounts of methyl [e.g., methylarsenate, MAs(V)] and aromatic arsenicals [e.g., roxarsone (4-hydroxy-3-nitrophenylarsonate, Rox(V)] have been utilized as herbicides for weed control and growth promotors for poultry and swine, respectively. The majority of these organoarsenicals degrade into more toxic inorganic species. Here, we demonstrate that the legume symbiont Sinorhizobium meliloti both reduces MAs(V) to MAs(III) and catalyzes sequential two-step reduction of nitro and arsenate groups in Rox(V), producing the highly toxic trivalent amino aromatic derivative 4-hydroxy-3-aminophenylarsenite (HAPA(III)). The existence of this process suggests that S. meliloti possesses the ability to transform pentavalent methyl and aromatic arsenicals into antibiotics to provide a competitive advantage over other microbes, which would be a critical process for the synthetic aromatic arsenicals to function as antimicrobial growth promoters. The activated trivalent aromatic arsenicals are degraded into less-toxic inorganic species by an MAs(III)-demethylating aerobe, suggesting that environmental aromatic arsenicals also undergo a multiple-step degradation pathway, in analogy with the previously reported demethylation pathway of the methylarsenate herbicide. We further show that an FAD-NADPH-dependent nitroreductase encoded by mdaB gene catalyzes nitroreduction of roxarsone both in vivo and in vitro. Our results demonstrate that environmental organoarsenicals trigger competition between members of microbial communities, resulting in gradual degradation of organoarsenicals and contamination by inorganic arsenic.

6.
Mol Genet Genomic Med ; : e1038, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31724315

RESUMO

BACKGROUND: Lumbar disc herniation (LDH) is a common musculoskeletal disorder affliction and associated with several genes polymorphism. Storkhead box 1 (STOX1) gene is a transcriptional factor related with several signaling pathways including inflammatory pathway. However, little is known about single-nucleotide polymorphisms (SNPs) of STOX1 associated with LDH risk. METHODS: We conducted a case-control study among 508 LDH cases and well-matched 508 controls, and six candidate SNPs in STOX1 were genotyped by Agena MassARRAY. Chi-squared test, genetic model, and haploview analysis were used to evaluate associations. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated by unconditional logistic regression. RESULTS: In the allelic model analysis, we found the minor allele "T" of rs7903209 and "A" of rs4472827 were associated with an increased risk of LDH (p = .029, p = .016). Furthermore, in the genotype model analysis, rs7903209 polymorphism was associated with the increased susceptibility of LDH based on dominant (p = .033) and additive model (p = .024); and rs4472827 variant was found to play a harmful role in the LDH risk based on genotype (p = .014), dominant (p = .012), and additive model (p = .015). In the haplotype analysis, the haplotype "GT" in block (rs10998461 and rs10998468) decreased LDH risk (OR = 0.7, 95% CI = 0.52-0.93, p = .016). Functional assessment indicated that rs7903209 and rs4472827 polymorphisms may influence the expression of STOX1. CONCLUSION: Our results provide evidence for polymorphisms of rs7903209 and rs4472827 in STOX1 associated with LDH risk in Chinese Han population.

7.
J Matern Fetal Neonatal Med ; : 1-6, 2019 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-31736410

RESUMO

Introduction: The efficacy of intravenous fluid supplementation for neonatal hyperbilirubinemia remains controversial. We conduct a systematic review and meta-analysis to explore the influence of intravenous fluid supplementation on treatment efficacy of neonatal hyperbilirubinemia.Methods: We search PubMed, Embase, Web of Science, EBSCO, and Cochrane Library databases through June 2019 for randomized controlled trials (RCTs) assessing the efficacy of intravenous fluid supplementation for neonatal hyperbilirubinemia. This meta-analysis is performed using the random-effect model.Results: Six RCTs are included in the meta-analysis. Overall, compared with control group for neonatal hyperbilirubinemia, intravenous fluid supplementation is associated with decreased TSB at 8 h (std. MD = -0.82; 95% CI = -1.46 to -0.17; p = .01), 12 h (std. MD = -0.46; 95% CI = -0.81 to -0.10; p = .01), 24 h (std. MD = -0.47; 95% CI = -0.78 to -0.16; p = .003) and 36 h (std. MD = -0.37; 95% CI = -0.73 to -0.02; p = .04), as well as reduced incidence of exchange transfusion (RR = 0.29; 95% CI = 0.14-0.59; p = .0006), but has no significant impact on duration of phototherapy (std. MD = -0.34; 95% CI = -0.88-0.21; p = .22).Conclusions: Intravenous fluid supplementation can provide additional benefits for the treatment of neonatal hyperbilirubinemia.

8.
Sci Total Environ ; : 134977, 2019 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-31757553

RESUMO

The optimization of more sustainable fertilization practice to relieve phosphorus (P) resource scarcity and increase P fertilizer utilization, a better understanding of the regulatory roles of microbes in P mobilization is urgently required to reduce P input. The genes phoD and pqqC are responsible for regulating organic and inorganic P mobilization, respectively. Using high-throughput sequencing, the corresponding bacterial communities harbored by these genes were determined. We conducted a 4-year rice-rice-crop rotation to investigate the responses of phoD- and pqqC-harboring bacterial communities to the partial replacement of inorganic P fertilizer by organic manure with reduced P input. The results showed that a combination of organic and inorganic fertilization maintained high rice yield, and also produced a more complex and stable phosphate mobilizing bacterial community, which contributed to phosphatase activities more than their gene abundances in the model analysis. Compared with the conventional mineral fertilization, organic-inorganic fertilization with the reduced P input slightly increased pqqC gene abundance while significantly enhanced the abundance of phoD-harboring bacteria, especially the genera Bradyrhizobium and Methylobacterium known as potential organic P mineralizers which can maintain high rice production. Moreover, the increased pH was the most impactful factor for the phoD- and pqqC-harboring bacterial communities, by promoting microbial P turnover and greatly increasing bioavailable P pools (H2O-Pi and NaHCO3-Pi, NaOH-Pi) in this P-deficient paddy soil. Hence, our study demonstrated that the partial replacement of mineral P with organic manure could reshape the inorganic phosphate solubilizing and alkaline-phosphomonoesterase encoding bacterial communities towards more resilient and effective to the high P utilization and productivity over intense cultivation, providing insights into the potential of soil microbes in the efficient management of agricultural P fertilization.

9.
Anal Chem ; 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31714062

RESUMO

With the ever-increasing demand for improved medical diagnosis, safe food supply, advanced biotechnology, and sustainable ecosystems, characterization of the microbial world by sensitive, specific, rapid, and quantitative tools is gaining more and more attentions. Surface-enhanced Raman spectroscopy (SERS) and its flexible integration with other tools, such as microscopes, stable isotope probing, microfluidic analysis, and chemometric analysis, have advanced rapidly and showed great promise for versatile microbial characterization. This perspective provides an overview of the recent advances of SERS and related coupling techniques for microbial diagnosis (e.g., identification and antibiotic resistance testing), phenotypic response profiling, microbial function assessment, in situ biofilm characterization, and multifunctional SERS tags. We further propose future requirements and the direction for SERS methodology to be headed, including standardization of SERS methodology, database generation and management, coupling with omics technology and single-cell sorting, and application in deciphering microbial processes.

10.
Int J Pharm ; : 118736, 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31756442

RESUMO

Oxaliplatin is a chemotherapeutic agent widely used in cancer treatment whereas its immunosuppressive effect hinders the progress of immunotherapy. Here we have synthesized a new compound NLGplatin constructed by combining oxaliplatin (OXA) and indoleamine 2,3-dioxygenase (IDO) inhibitor NLG919. The NLGplatin acquires chemotherapeutic properties of OXA and can activate the immune system, and also retains the ability to inhibit IDO enzyme activity without affecting the proliferation of immune cells. This difunctional drug has a great potential to achieve effective cancer chemoimmunotherapy.

11.
ChemSusChem ; 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31682086

RESUMO

Fabrication of efficient and convenient photocatalytic H2-evolving system is a fascinating research topic in the field of solar energy conversion. Herein, an original ternary self-assembled system was fabricated by supramolecular host-guest chemistry. The system was led by macrocyclic compound cucurbit[7]uril (CB[7]) and it was used for photocatalytic H2 evolution. In this system, a H2 evolution catalyst, namely, [Co(dmgH)2(4-ppy)2]NO3 (1)and a photosensitizer Eosin Y (EY) were assembled with CB[7] via inclusion and exclusion interactions, respectively. The synchronous self-assembly drives an orthogonal arrangement for 1@CB[7]/EY system. The inclusion complex 1@CB[7] was successfully characterized by 1 H NMR and single-crystal X-ray diffraction. The the exclusion process of CB[7] with EY was identified by NMR titration and the optimized geometry of exclusion structure was determined by density functional theory calculations. was found to be remarkable, which resulted in a 6-fold increase in turnover numbers, a 3-fold enhancement in turnover frequency, and a 3-fold extension in lifetime for photocatalytic H2 evolution  as compared to the system in the absence of CB[7]. The improvement of light driven activity toward H2 evolution was ascribed to the linking effect of CB[7] between photosensitizer and catalyst.

12.
Gene ; : 144197, 2019 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-31669636

RESUMO

Enterococcus faecalis is one of the main components of symbiotic bacteria in the intestine of silkworm (Bombyx mori L.). The abundance of E. faecalis in the intestine of silkworm is affected by fluoride exposure. However, the response mechanism of E. faecalis toward fluoride remains largely unknown. In this study, a strain of E. faecalis (named TV4), which is a symbiotic bacteria of silkworm, was isolated and characterized. Inhibition assay showed that fluoride could significantly inhibit the growth of the TV4 strain (P<0.05) after culture for 4 h. Finally, Illumina X-Ten platform was used to investigate the response mechanism of E. faecalis TV4 under fluoride exposure. We found that the TV4 strain demonstrated significant changes in its carbohydrate transport and metabolism and energy metabolism. The transcriptome sequencing results revealed that 237 genes were differentially expressed for TV4 grown after fluoride exposure, i.e., 92 genes were differentially up-regulated and 145 genes were differentially down-regulated. Many of the down-regulated genes were involved in cell carbohydrate transport and metabolism and energy production, whereas the up-regulated genes were mostly related to ethanolamine utilization and amino acid synthesis and metabolism. Our results revealed that strain TV4 reduced its carbohydrate metabolism and energy metabolism and increased ethanolamine utilization and amino acid metabolism to adapt and survive under fluoride exposure. This study enhances our understanding about the response mechanism of E. faecalis after fluoride exposure and has important implications for investigations on the three-way interaction among fluoride, symbiotic bacteria and silkworm.

13.
J Orthop Surg Res ; 14(1): 370, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31729995

RESUMO

BACKGROUND: The best treatment for lesions of the long head of the biceps tendon (LHBT) with concomitant reparable rotator cuff tears is still controversial. The purpose of the meta-analysis was to compare clinical outcomes of biceps tenotomy and tenodesis for LHBT lesions. METHODS: A literature retrieval was conducted in MEDLINE, Embase, and Cochrane Library from 1979 to March 2018. Comparative studies (level of evidence I or II) comparing tenotomy and tenodesis for LHBT lesions with concomitant reparable rotator cuff tears were included. Risk of bias for all included studies was assessed using the Cochrane Collaboration's risk of bias tool. Clinical outcomes compared were Popeye sign, Constant score, VAS pain score, cramping pain, elbow flexion and forearm supination strength, and re-tear of the rotator cuff. RESULTS: Two randomized controlled trials (RCTs) and five prospective cohort studies (PCS) with 288 biceps tenotomy patients and 303 biceps tenodesis patients were included in this review. Tenotomy resulted in significantly greater rates of Popeye sign (RR, 2.70 [95% CI, 1.80 to 4.04]; P < 0.01) and a less favorable Constant score (MD, - 1.09 [95% CI, - 1.90 to - 0.28]; P < 0.01) compared to tenodesis. No significant heterogeneity was found between the two groups across all parameters except forearm supination strength. CONCLUSIONS: The current evidence indicates that biceps tenodesis for LHBT lesions with concomitant reparable rotator cuff tears results in decreased rate of Popeye sign and improved Constant score compared to biceps tenotomy. TRIAL REGISTRATION: PROSPERO, CRD42018105504. Registered on 13 August 2018.

14.
Genes Cells ; 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31730247

RESUMO

In Bombyx mori, there are more than 30 mutant strains exhibiting the translucent larval skin resulting from a decrease in the uric acid content in epidermal cell. Of these, the chinese translucent (oc) mutant presents a moderately translucent larval skin. Previously, we narrowed the region linked to the oc phenotype to approximately 234 kb by positional cloning, and found that BmMCT9 was severely suppressed in the mutant. Here, we analyzed the mutation and potential molecular function of BmMCT9. Sequence analysis showed that a 2,624 bp fragment of BmMCT9 promoter region was replaced by a 22 bp sequence in the mutant. Luciferase reporter gene assay confirmed that BmMCT9 promoter activity in the mutant was significantly lower than that in the wild type. Knockdown of BmMCT9 caused a translucent phenotype in the first-instar silkworm larvae. Immunoblotting analysis showed that BmMCT9 expression was severely reduced in the mutant than in the wild type, and immunofluorescence showed that BmMCT9 existed mainly within the cytoplasm of epidermal cells. Together, our results suggest that reduced levels of BmMCT9 was responsible for the translucent phenotype of oc mutant, and that BmMCT9 might function in intracellular vesicles facing the cytoplasm including urate granules in silkworm integument.

15.
Microbiome ; 7(1): 143, 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31672173

RESUMO

BACKGROUND: N fixation is one of the most important microbially driven ecosystem processes on Earth, allowing N to enter the soil from the atmosphere, and regulating plant productivity. A question that remains to be answered is whether such a fundamental process would still be that important in an over-fertilized world, as the long-term effects of fertilization on N fixation and associated diazotrophic communities remain to be tested. Here, we used a 35-year fertilization experiment, and investigated the changes in N fixation rates and the diazotrophic community in response to long-term inorganic and organic fertilization. RESULTS: It was found that N fixation was drastically reduced (dropped by 50%) after almost four decades of fertilization. Our results further indicated that functionality losses were associated with reductions in the relative abundance of keystone and phylogenetically clustered N fixers such as Geobacter spp. CONCLUSIONS: Our work suggests that long-term fertilization might have selected against N fixation and specific groups of N fixers. Our study provides solid evidence that N fixation and certain groups of diazotrophic taxa will be largely suppressed in a more and more fertilized world, with implications for soil biodiversity and ecosystem functions.

16.
J Invest Surg ; : 1-5, 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31769307

RESUMO

Purpose/Aim: This study aims to compare efficacy and safety of Low-profile Visualized Intraluminal Support (LVIS) stent and Pipeline Embolization Device (PED)-assisted endovascular interventions in patients with middle cerebral arterial aneurysms. Materials and methods: This retrospective study included a total of 144 MCA patients, who went to our hospital from January 2013 to December 2017. These patients were divided into two groups: LVIS group, 81 cases; PED group, 63 cases. Then, the basic clinical characteristics were collected. The Raymond grade was used to evaluate the embolism immediately after the surgery and at six months after surgery. The Glasgow Outcome Scale (GOS) and modified Rankin scale were used at six months after surgery, and the recurrence rate was also recorded. Results: The mean aneurysm diameter was 7.7 ± 5.1, which range from 2-25 mm. There were 25 cases with ruptured aneurysms. The results revealed that 57 (70.4%) cases in the LVIS group and 41 (65.1%) cases in the PED group presented with complete embolisms immediately after the surgery. The mean GOS score after six months was 4.6 ± 0.9 in the LVIS group and 4.6 ± 0.9 in the PED group. Furthermore, a total of 86.4% cases had a good prognosis in the LVIS group, while 87.3% cases had a good prognosis in the PED group. Moreover, recurrence was found in six (7.4%) cases in the LVIS group and in five (7.9%) cases in the PED group. Conclusion: Both these two methods are effective and safe, with a high good prognosis rate and low recurrence. However, there was no significant difference between the PED and LVIS stent methods.

17.
FEMS Microbiol Ecol ; 95(11)2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31689345
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