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1.
Methods Mol Biol ; 2050: 175-179, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31468492

RESUMO

Electroporation refers to the application of high strength electric pulse to create transient pores in the membrane, thereby enabling the passage of hydrophilic molecules into the cells. Based on the properties of cell and cell wall, the electroporation parameters vary among the algal species. Here, we demonstrated the optimized protocol for successful introduction of recombinant DNA (~5000 bp) into Nannochloropsis oceanica. The linearized recombinant plasmid that harbors eGFP and Bh-sle as the reporter and marker gene, respectively, was electroporated into the electrocompetent N. oceanica cells at voltage of 2200 V, 50 µF, resistance at 600 Ω using electroporator, and the transformed cells were then screened by molecular analysis. The report exemplifies a straightforward and reliable electroporation strategy for generating transgenic N. oceanica cells.

2.
J Nanosci Nanotechnol ; 20(3): 1873-1877, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492355

RESUMO

The structure and anisotropic magnetization of One-dimensional (1D) Nd/Co/PA66 coaxial nanocables prepared by a low cost physical infiltration and electrodeposition methods are investigated. The preparation of Co nanotubes, Co/PA66 two-layer nanotubes and Nd/Co/PA66 three-layer nanocales is described, respectively. The structure, chemical composition and magnetic properties of various nanomaterials were investigated. The results show that the magnetic properties were affected by the rare earth metal Nd and the structural properties. The residual magnetization ratio of Nd/Co/PA66 nanocables is the biggest due to the synergistic effect of Nd and Co. In addition, the magnetization processes of the nanostructure were discussed in detail. We believe that these methods may provide an idea for ferromagnetic alloys and permanent magnet material and suitable for future applications in perpendicular recording media.

3.
J Cell Physiol ; 235(1): 548-562, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31232471

RESUMO

Accumulating evidence implies that N6-methyladenosine (m6A) methylation participated in the tumorigenesis of gastric cancer (GC). Here we synthetically analyzing the prognostic value and expression profile of seven m6A methylation-relevant genes through silico analysis of sequencing data downloaded from The Cancer Genome Atlas, Kaplan-Meier plotter, and Gene Expression Omnibus database. We explored the methyltransferase-like 3 (METTL3) expression in GC cell line and tumor tissues by reverse transcription quantitative polymerase chain reaction and western blot analysis. The m6A methylation status of total RNA was measured by m6A RNA methylation quantification kit. Small interfering RNA was used to establish METTL3 knockdown cell lines. We also measure the proliferation and migration capability GC cell. Furthermore, we detect the epithelial cell mesenchymal transition marker and m6A methylation level after METTL3 knock down. Our result revealed that METTL3 was significantly increased in GC tissues compared with control in big crowd data sets. Survival analysis showed that METTL3 serve as a poor prognostic factor for GC patients. The expression level of METTL3 gradually increased with the progress of tumor stage and grade. GFI1 is an important transcription factor associated with METTL3. We verified the up-trend of METTL3 in messenger RNA and protein expression and observed a significant increase in the m6A methylation status of total RNA in the GC cells and tissues. METTL3 knockdown inhibited total RNA m6A methylation level, as well as cell proliferation and migration capacity. Moreover, METTL3 knockdown decreased α-smooth muscle actin. Taken together, our finding revealed that m6A methylation writer METTL3 serve as an oncogene in tumorigenesis of GC.

4.
Int J Surg ; 71: 140-148, 2019 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-31568844

RESUMO

BACKGROUND: Despite increasing evidence demonstrated robot-assisted distal gastrectomy (RADG) is safe and feasible for the treatment of advanced gastric cancer (AGC), robot-assisted total gastrectomy (RATG) remains a challenging procedure due to its technical difficulties and possible postoperative complications (POCs). This study aimed to systematically evaluate POCs following RATG. METHODS: Between January 2017 and January 2019, 319 AGC patients with pathological stage T2-4aN0-3M0 who underwent RADG or RATG were enrolled. POCs were stratified using the Clavien-Dindo classification. One-to-one propensity score matching was performed to reduce confounding differences. RESULTS: After matching, 266 patients met the criteria for further analysis. Ultimately, 64 patients (24.1%) who developed POCs had 126 clinical manifestation events. Overall the POCs rate was significantly greater after RATG in comparison with RADG (29.3% vs. 18.8%; P = 0.045), and more major POCs (Clavien-Dindo grade ≥ IIIa) were observed in the RATG group (14.3% vs. 5.3%; P = 0.013). The POCs were then classified into local and systemic POCs. The rates of local POCs (35.3% vs. 19.5%; P = 0.004) and systemic POCs (24.8% vs. 15.0%; P = 0.046) were significantly higher in the RATG group than the RADG group. Subgroup analysis showed that the anastomotic leakage rate was higher after RATG (5.3% vs. 0.8%; P = 0.031), whereas the remaining POCs were similar between the two groups. Patients with higher POCs significantly had longer postoperative length of stay (R = 0.895, P = 0.003). Multivariate analysis confirmed age, extent of resection, and TNM stage were risk factors for all POCs. CONCLUSIONS: These findings demonstrated that RATG is technically feasible and safe for treatment of AGC with acceptable morbidity and mortality rates. The POCs rate of RATG was higher than RADG, especially for anastomotic leakage. More effective anastomotic techniques are needed in RATG to prevent leakage.

5.
Environ Pollut ; 255(Pt 2): 113292, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31597112

RESUMO

The wide application of bisphenol A (BPA) leads to the emergence of BPA residuals in natural water environments. Dissolved organic matter (DOM) existed in water can bind with BPA, hence influencing the migration and transformation of BPA in aquatic environments. pH is a crucial factor governing the binding interactions between DOM and BPA. However, the mechanisms driven the binding process under different pH conditions are still unclear. In this study, the interactions between BPA and humic acids (HA), a primary component of DOM, are investigated over a wide pH range of 3-12 by integrating fluorescence quenching, dynamic light scattering and microcalorimetry. pH dependence of the binding interactions between HA and BPA are interpreted from a thermodynamic perspective. The results indicate that HA can spontaneously interact with BPA to form a stable HA-BPA complex. With the increasing pH, the binding interactions change from entropy driven to entropy-enthalpy co-driven. Hydrophobic force dominate the binding interactions under acidic condition. The synergy of hydrophobic force and hydrogen bond promotes the binding process under neutral condition. Under alkaline conditions, electrostatic repulsion participates the binding process in addition to hydrophobic force and hydrogen bond, weakening the binding strength. Therefore, neutral pH is favorable for HA to bind with BPA, consequently enhancing the dissolution of BPA in natural water bodies. The results are beneficial to better understand the pH dependent distribution of BPA in aquatic environments.

6.
Medicine (Baltimore) ; 98(39): e17043, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31574801

RESUMO

RATIONALE: Post-hysterectomy collision tumors of the vulva has rarely been reported. Though long-term HPV infection may induce vulva tumor, but the relationship between HPV infection and collision vulva tumor is not clear. And there are no clear rules of the post-hysterectomy cancer surveillance for human papilloma virus (HPV) long-term infections. So here we first report a case of post-hysterectomy rare collision vulva tumor with long-term HPV infection composed of squamous cell carcinoma of the labia major and adenosquamous carcinoma of bartholin gland and hope to bring new direction to our future research. PATIENT CONCERNS: A 48-year-old woman with long-term HPV infection, 3 years after hysterectomy, gravida 3, para 2, was admitted to our hospital with complaints of a 4-month history of an itching vulva ulceration. An anabrosis was located on the surface of the solid mass of the bartholin gland at the posterior part of the right labium and the right inguinal lymph nodes were palpable. Result of the incisional biopsy of the ulcer area at local hospital was atypical squamous cells couldn't exclude high-grade squamous intraepithelial lesion (ASC-H). Subsequently more authoritative pathological consultation results suggested squamous cell carcinoma of the vulva. DIAGNOSES: Post-hysterectomy collision vulva tumor with long-term HPV infection composed of squamous cell carcinoma of the labia major and adenosquamous carcinoma of bartholin gland. INTERVENTIONS: The extensive excision of the vulva, bilateral inguinal lymph nodes dissection, and local skin flap transposition surgeon was done to this patient. The final certificate diagnosis was: vulvar tumor T1bM0N0 composed of squamous cell carcinoma of the labia major and adenosquamous carcinoma of bartholin gland; HPV infection; post hysterectomy, and bilateral salpingectomy. OUTCOMES: The patient recovered well after surgery, and consequently received 6 courses of TC (paclitaxel + carboplatin) chemotherapy, and 9 months and 13 days followed up. So far patient recorded as complete response (CR). LESSONS: Collision vulva tumor occurred post-hysterectomy is extremely rare. It is most likely related to long-term HPV infection, which suggests us should to modify the manner of the post-hysterectomy cancer surveillance for HPV long-term infections. For patients with high-risk HPV infection, even if the cytology results are negative, we may should perform colposcopy and vulva biopsy more positively to prevent the disease from progressing into cancer. And the pathogenesis of relationship between HPV infection and collision vulva tumor is still need further investigation.


Assuntos
Glândulas Vestibulares Maiores , Carcinoma Adenoescamoso/diagnóstico , Carcinoma de Células Escamosas/diagnóstico , Histerectomia , Neoplasias Primárias Múltiplas/diagnóstico , Infecções por Papillomavirus/diagnóstico , Complicações Pós-Operatórias/diagnóstico , Neoplasias Vulvares/diagnóstico , Glândulas Vestibulares Maiores/patologia , Biópsia , Carcinoma Adenoescamoso/patologia , Carcinoma Adenoescamoso/virologia , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/virologia , Colposcopia , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Primárias Múltiplas/patologia , Neoplasias Primárias Múltiplas/virologia , Infecções por Papillomavirus/patologia , Complicações Pós-Operatórias/patologia , Complicações Pós-Operatórias/virologia , Neoplasias Vulvares/patologia , Neoplasias Vulvares/virologia
7.
Psychophysiology ; : e13486, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31595978

RESUMO

Recent studies show that taxonomic and thematic relationships are functionally and neurologically dissociated; however, there remain some discrepancies due to inconsistencies in definitions, task properties, and concept domains. This issue was further explored via the semantic priming paradigm with a long SOA of 600 ms while controlling for perceptual or functional features of artifacts involved across taxonomic and thematic relationships. Six conditions were compared: perceptual relationship (axe-helve), functional relationship (axe-wood), perceptual classification (axe-hammer), functional classification (axe-saw), unrelated condition (axe-skates), and nonword (axe-derf) conditions. Behavioral priming effects are found for all related conditions relative to unrelated conditions except for perceptual relationships, whereas semantic priming effects (smaller N400 amplitude) are found for functional relationships and perceptual classification relative to unrelated conditions but not for perceptual relationships and functional classification, indicating perceptual features are less important than functional features for artifacts. Furthermore, the frontal negativity elicited by functional relationships is smaller than all other related conditions at 400-550 ms, while it is only smaller than functional classification at 550-650 ms. These results indicate that, besides different features, taxonomic and thematic relationships are dissociated to organize object knowledge, which is primarily fuelled by feature processing, with taxonomic, or thematic, relationships further embedded with such sensory, or functional, features.

8.
Artigo em Inglês | MEDLINE | ID: mdl-31603299

RESUMO

Prussian Blue Analogues (PBAs) are considered to be ideal multivalent cation host materials due to their unique open-framework structure. In aqueous solution, however, the PBAs' cathodes have a low reversible capacity limited by the single electrochemical group Fe(CN)63- and high crystal water content. They also suffer from fast cycle fading resulting from significant oxygen/hydrogen evolution and cathode dissolution. In this work, a high capacity PBA-type FeFe(CN)6 cathode with double transition metal redox sites is successfully demonstrated in 5 m Al(CF3SO3)3 Water-in-Salt electrolyte (Al-WISE). Due to Al-WISE having a wide electrochemical window (2.65 V) and low dissolution of the cathode, our PBA cathode exhibits a high discharge capacity of 116 mAh/g and the superior cycle stability >100 cycles with capacity fading of 0.39% per cycle.

9.
Technol Cancer Res Treat ; 18: 1533033819871300, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31564215

RESUMO

Non-coding RNAs, originally considered junk gene products, have taken center stage in view of their significant involvement in a spectrum of biological processes during human development, thereby offering novel therapeutic targets for improvement of treatment options. Accumulating evidence has demonstrated non-coding RNA dysfunction across various human cancers. In particular, microRNAs have emerged as key regulatory molecules in cancer biology. MicroRNAs are noninvasive, readily accessible biomarkers that can be effectively applied for diagnosis and prognosis of different tumor types, including colon cancer. In this study, we reanalyzed the available data with bioinformatics tools to identify differentially expressed microRNAs in colon cancer cells. The top 3 upregulated microRNAs (miR-10, miR-199, and miR-122) in colon cancer cells were further validated in tissues of clinical patients via reverse transcription-quantitative polymerase chain reaction. Our results showed that miR-122 significantly promotes the proliferation and invasion ability of SW480 and SW620 cells through inhibition of Aldolase, Fructose-Bisphosphate A (ALDOA) expression. We further summarized recent advances in our understanding of the functional relevance of microRNAs in cancer development and discussed the possible implications of specific microRNAs in colon cancer. This study extends our knowledge of microRNA involvement in colon cancer biology and presents novel candidates for the development of attractive therapeutic strategies.

10.
J Coll Physicians Surg Pak ; 29(10): 958-961, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31564270

RESUMO

OBJECTIVE: To explore the effect and safety of laparoscopic partial nephrectomy (LPN) and open partial nephrectomy (OPN) in the treatment of complex renal tumours and to compare renal function in the perioperative period. STUDY DESIGN: Comparative study. PLACE AND DURATION OF STUDY: Departments of Urology and Cardiovascular Medicine, Affiliated Hospital of Hebei University, from July 2016 to June 2018. METHODOLOGY: A total of 168 complex renal tumour patients with renal tumour scoring system scores (R.E.N.A.L) <7 and tumour stages of T1aN0M0~TlbN0M0 (diameter of tumour <7 cm without metastasis) were chosen. The patients were classified into the retroperitoneal laparoscopic partial nephrectomy (RLPN) group and open partial nephrectomy (OPN) group, comprising 84 patients in each group. Intraoperative and postoperative characteristics of both groups were compared. Statistical analysis of the occurrence rate of postoperative complications was conducted. Renal function indicators, including serum urea (UREA), creatinine (Cr), uric acid (UA) and glomerular filtration rate (GFR), were evaluated one day before the operation and one week after the operation. RESULTS: The differences between the two groups in intraoperative renal warm ischaemia time (WIT) and postoperative drainage time were not statistically significant. Compared with OPN group, RLPN group had shorter recovery time of gastrointestinal function, less use of analgesics and longer hospital stay. The difference in the recent occurrence rate of complications was not statistically significant. The differences between the two groups in UREA, Cr, UA and GFR one day before the operation and one week after the operation were not statistically significant (p>0.05). The Cr and UA levels of both groups improved significantly after the operation, and the GFR level declined significantly. The differences were statistically significant compared with preoperation levels (p<0.05). CONCLUSION: The effect and safety of RLPN in the treatment of complex renal tumours are equal to those of open operations. Laparoscopic surgery involves a small operative wound and contributes to renal function recovery, allowing patients to recover quickly; however, laparoscopic surgery has high technical requirements for its operators.

11.
Artigo em Inglês | MEDLINE | ID: mdl-31581088

RESUMO

In DNA nanotechnology, the aim in folding DNA origami is to find a good piece of rectangular DNA origami with desired sizes, which could be larger or smaller for different application purposes. In recent three years, the technique of folding smaller ones is paid heavily attentions. In this work, we design a programming rectangular DNA origami in size 20*30nm with M13p18, which is smallest and cheapest to the best acknowledge of the authors. Since it is not hard to prepare with 30 staple strands and short annealing time, the cost of folding our designed rectangular DNA origami is less than 100 dollars. Although the large origami give more space, the smaller ones are cheaper and has the potential applications in penetrating cancer cells. It is obtained by cell penetrating experiments that our designed rectangular DNA origami can penetrate ovarian cancer cells efficiently even loading doxorubicin, but the thermodynamic stability needs further improved. Our designed programming 20-30nm triangular DNA origami shows potential applications in precision control of nanoscale particles and anti-tumor drug delivery in vivo.

12.
Chin Med J (Engl) ; 132(19): 2354-2361, 2019 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-31567382

RESUMO

BACKGROUND: In our previous paper, we demonstrated that Connexin 43 (CX43) was highly expressed in bladder cancer (BC) tissues. But the molecular mechanism about microRNAs (miRNAs) regulation upstream of CX43 in BC has not been well elucidated and remains to be further studied. MicroRNA-139-5p (miR-139-5p) is a tumor suppressor in progression of multifarious cancers including BC. Nevertheless, the underlying mechanisms of CX43/miR-139-5p in tumorigenesis of BC are still not well illustrated. The specific objective of our study was to inquiry the effect of CX43/miR-139-5p on BC progression and its underlying mechanism. METHODS: The bioinformatics analysis softwares were applied to predict the miRNAs in the upstream of CX43. First, the expression levels of miR-139-5p in BC tissues (tumor) and paracancer tissues (normal) were investigated using the data from The Cancer Genome Atlas database. Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was used to detect the mRNA expression level of miR-139-5p in three human BC cell lines 5637, T24, ECV-304 and a human bladder epithelial immortalized cell line SV-HUC-1 (normal control). Then si-CX43, si-control, miR-139-5p mimic, and its negative control (NC) were transfected into BC cell line ECV-304. The relationship of miR-139-5p and CX43 was analyzed by dual-luciferase reporter assay. The qRT-PCR and Western blotting were used to test the mRNA and protein expression level of CX43. The proliferation of ECV-304 and T24 cells were examined by cell counting kit-8. The migration and invasion of ECV-304 cells were tested by transwell assay. To determine whether miR-139-5p would affect cell proliferation, migration and invasion by targeting CX43, we executed the rescue assay. The comparison between two groups was analyzed by Student's t test, and comparisons among multiple samples were performed by one-way analysis of variance and a Bonferroni post hoc test. RESULTS: The expression of miR-139-5p was remarkably down-regulated in BC tissues (tumor vs. normal, 2.286 ±â€Š0.017 vs. 3.211 ±â€Š0.034, t = 11.540, P < 0.0001) and cell lines (P < 0.01 in all BC cell lines). Besides, we also indicated that over-expression of miR-139-5p reduced the proliferation of ECV-304 (P = 0.001) and T24 cells (P = 0.005). Moreover, miR-139-5p over-expression weakened the invasion (P = 0.001) and migration (P = 0.001) of ECV-304 cells. Furthermore, the relative luciferase activity of CX43-wild type construct was distinctly lessened by up-regulation of miR-139-5p (miR-139-5p mimic NC vs. miR-139-5p mimic, 0.916 ±â€Š0.063 vs. 0.356 ±â€Š0.048, t = 7.085, P = 0.002), nevertheless the activity of CX43-mutant type construct was untouched (miR-139-5p mimic NC vs. miR-139-5p mimic, 0.918 ±â€Š0.057 vs. 0.878 ±â€Š0.039, t = 0.577, P = 0.595). Finally, the rescue assay revealed that CX43 deletion enhanced the depressor effect of miR-139-5p on ECV-304 cell proliferation (P < 0.01), invasion (P = 0.028), and migration (P = 0.014). CONCLUSION: MiR-139-5p, as a tumor-suppressor, repressed cell proliferation, invasion, and migration in BC, which might be achieved by regulating CX43.

13.
J Biochem Mol Toxicol ; : e22405, 2019 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-31593333

RESUMO

Ankylosing spondylitis (AS) is a high disability and greatly destructive disease. In this study, we preliminarily studied the function and mechanism of bilobalide (BIL) on interleukin (IL)-17-induced inflammatory injury in ATDC5 cells. CCK-8 and migration assays were used to detect the functions of IL-7, BIL, and microRNA (miR)-125a on cell viability and migration. The miR-125a level was changed by transfection, and tested by real-time quantitative polymerase chain reaction. Additionally, Western blot tested the levels of inflammatory factors (IL-6 and tumor necrosis factor-α), matrix metalloproteinases (MMPs), and pathway-related proteins. Moreover, the enzyme-linked immunosorbent assay also was used to detect inflammatory factor levels. IL-7 was used to construct an inflammatory injury model in ATDC5 cells. Based on this, BIL inhibited IL-17-induced cell viability, migration, and expressions of inflammatory factors and MMPs. Furthermore, we found BIL negatively regulated miR-125a, and the miR-125a mimic could partly reverse the effects of BIL on IL-17-injury. Finally, we showed that BIL inhibited the c-Jun N-terminal kinase (JNK) and nuclear factor kappa B (NF-κB) pathways, and the miR-125a mimic had the opposite effect. BIL inhibited IL-17-induced inflammatory injury in ATDC5 cells by downregulation of miR-125a via JNK and NF-κB signaling pathways.

14.
Medicine (Baltimore) ; 98(39): e17124, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31574812

RESUMO

INTRODUCTION: Spasticity is the most common complication after stroke, which is the main obstacle in the recovery of motor function. Spasticity seriously affects the quality of life and brings a heavy burden to families and society. Acupuncture is an effective method for stroke. However, whether acupuncture is effective for poststroke spasticity is still unknown. The purpose of this systematic review (SR) is to evaluate the effectiveness and safety of acupuncture for poststroke spasticity. METHODS AND ANALYSIS: We will search the following databases from inception to July 2019: China Biology Medicine (CBM), China National Knowledge Infrastructure (CNKI), Wan Fang Data, the Chinese Science and Technology Periodical Database (VIP), PubMed, Embase, The Cochrane Library, and Web of Science. All relevant randomized controlled trials (RCTs) utilizing acupuncture for poststroke spasticity will be included. The primary outcome is the modified Ashworth scale. Secondary outcomes include composite spasticity scale, clinic spasticity index, electromyographic activity, Hoffmann reflex activity, or other spasticity-related outcomes. Study selection, data extraction, and quality assessment will be performed independently by 2 reviewers. Assessment of risk of bias and data synthesis will be conducted using Review Manager V5.3 software. ETHICS AND DISSEMINATION: The ethical approval is not required since SR is based on published studies. The results of this SR will be published in a peer-reviewed scientific journal according to the Preferred Reporting Item for Systematic Review and Meta-analysis (PRISMA) guidelines. PROSPERO REGISTRATION NUMBER: CRD42019129779.

15.
Vet Med Sci ; 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31589010

RESUMO

BACKGROUND: Porcine infectious pleuropneumonia caused by Actinobacillus pleuropneumoniae (App) is one of the most serious infectious diseases in pigs and has brought huge economic losses to the world pig industry. The aim of this trial was to evaluate the effect of enteric-coated tilmicosin granule in the treatment and control of artificial infection of App. METHODS: Sixty Duroc and Yorkshire crossbred pigs (50 of which were artificially infected) were divided into six groups: BCG (Blank control group), ICG (Infection-only control group), HDG (High-dose enteric-coated tilmicosin granules), MDG (Medium-dose enteric-coated tilmicosin granules), LDG (Low-dose enteric-coated tilmicosin granules) and TPG (Tilmicosin premix drug control group). The cure rate, mortality, clinical respiratory score, body temperature score, weight gain, lung score and so on were recorded. RESULTS: The cure rate of HDG and MDG was as high as 90%, the mortality was 10%, and the clinical signs recovered quickly. CONCLUSION: The results showed that enteric-coated tilmicosin granules had obvious therapeutic effect on artificial infection, which could reduce the damage caused by the disease and reduce the mortality.

16.
Environ Pollut ; 255(Pt 2): 113235, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31561036

RESUMO

The role of sediment-bound organic phosphorus (Po) as an additional nutrient source is a component of internal P budgets in lake system that is usually neglected. Here we examined the relative importance of sediment Po to internal P load and the role of bioavailable Po in algal growth in Lake Erhai, China. Lake Erhai sediment extractable Po accounted for 11-43% (27% average) of extractable total P, and bioavailable Po accounted for 21-66% (40%) of Po. The massive storage of bioavailable Po represents an important form of available P, essential to internal loads. The bioavailable Po includes mainnly labile monoester P and diester P was identified in the sequential extractions by H2O, NaHCO3, NaOH, and HCl. 40% of H2O-Po, 39% of NaHCO3-Po, 43% of NaOH-Po, and 56% of HCl-Po can be hydrolyzed to labile monoester and diester P, suggesting that the bioavailability of Po fractions was in decreasing order as follows: HCl-Po > NaOH-Po > H2O-Po > NaHCO3-Po. It is implied that traditional sequential fractionation of Po might overestimate the availability of labile Po in sediments. Furthermore, analysis of the environmental processes of bioavailable Po showed that the stabler structure of dissloved organic matter (DOM) alleviated the degradation and release of diester P, abundant alkaline phosphatase due to higher algal biomass promoted the degradation of diester P. The stability of DOM structure and the degradation of diester P might responsible for the spatial differences of labile monoester P. The biogeochemical cycle of bioavailable Po replenishs available P pools in overlying water and further facilitate algal growth during the algal blooms. Therefore, to control the algal blooms in Lake Erhai, an effective action is urgently required to reduce the accumulation of Po in sediments and interrupt the supply cycle of bioavailable Po to algal growth.

17.
Obes Rev ; 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31482658

RESUMO

Childhood obesity is one of the most pressing public health issues nowadays. The environmental factors have been identified as potential risks for obesity, as they may influence people's lifestyle behaviours. Lack of access to supermarkets that usually provide healthy food options has been found to be a risk factor for childhood obesity in several studies. However, findings remained inconclusive. We aimed to systematically review the association between access to supermarkets and childhood obesity. A literature search was conducted in the Cochrane Library, PubMed, Web of Science, and Embase for studies published before 1 January 2019. Twenty-four studies conducted in four countries were identified, from which data on the basic characteristics of studies and participants, measures of access to supermarkets, and associations between access to supermarkets and weight-related behaviours and outcomes were extracted. The median sample size was 1858 participants. Half of the included studies indicated a negative association, one fourth reported a positive association, and the remaining one fourth did not find a significant association. Better designed studies are necessary to achieve a robust understanding of this epidemiological relationship in the future.

18.
Arch Pharm (Weinheim) ; : e1900129, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31478565

RESUMO

To gain further knowledge of the structure-activity relationship and druggability of novel oxazolidinone-based UDP-3-O-acyl-N-acetylglucosamine deacetylase (LpxC) inhibitors as Gram-negative antibacterial agents, compounds containing the hydrophobic tails with different lengths and terminal substitutions were synthesized and their antibacterial activities against standard and clinically isolated Gram-negative strains were evaluated. We summarized their structure-activity relationships and found that oxazolidinone-based compounds exhibited a narrower antibacterial spectrum compared with threonine-based compounds. Furthermore, we parallelly compared the metabolic stabilities of the compounds with the classic threonine scaffold and the novel oxazolidinone scaffold in liver microsomes. The results indicated that the druggability of the oxazolidinone scaffold may be inferior to the classic threonine scaffold in the design of LpxC inhibitors.

19.
Cereb Cortex ; 2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31512720

RESUMO

Men and women process language differently, but how the brain functions to support this difference is poorly understood. A few studies reported sex influences on brain activation for language, whereas others failed to detect the difference at the functional level. Recent advances of brain network analysis have shown great promise in picking up brain connectivity differences between sexes, leading us to hypothesize that the functional connections among distinct brain regions for language may differ in males and females. To test this hypothesis, we scanned 58 participants' brain activities (28 males and 30 females) in a semantic decision task using functional magnetic resonance imaging. We found marked sex differences in dynamic interactions among language regions, as well as in functional segregation and integration of brain networks during language processing. The brain network differences were further supported by a machine learning analysis that accurately discriminated males from females using the multivariate patterns of functional connectivity. The sex-specific functional brain connectivity may constitute an essential neural basis for the long-held notion that men and women process language in different ways. Our finding also provides important implications for sex differences in the prevalence of language disorders, such as dyslexia and stuttering.

20.
Dalton Trans ; 48(36): 13753-13759, 2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31475701

RESUMO

In this work, we present the hydrothermal synthesis of delafossite oxide Ca-doped CuCoO2 (CCCaO) nanosheets at a low temperature of 100 °C. The crystal phase, morphology and chemical composition of these CuCoO2 (CCO) based samples were comprehensively characterized by powder X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy. The size of CCCaO nanosheets decreased with increasing Ca dopant concentration, and the optimized CCCaO nanosheets (∼490 nm in lateral size and ∼15 nm in thickness) were much smaller than CCO nanocrystals (∼540 nm in lateral size and 85 nm in thickness). The specific surface area of these CCO based samples increased with increasing Ca content, and the optimized CCCaO nanosheets present a high BET surface area of 28 m2 g-1. XPS and Raman spectroscopy analyses indicate Ca2+ dopant substitution on the Cu+ site in CCCaO nanosheets. Moreover, the effects of Ca2+ doping on the optical and electrical properties of these CCO based samples were further studied. The optical properties measured at room temperature show high absorbability (up to 90%) in the ultraviolet-visible-near infrared (UV-VIS-NIR) region, and the indirect band gap shows a significant blue-shift with increasing Ca2+ concentration. The CCO nanocrystals possess a higher electrical conductivity than the CCCaO nanosheets, and present good conductivities of around 12.81, 4.47 and 0.69 s m-1 for the CCO and CCCaO samples at room temperature. The facile fabrication process, tunable crystallite sizes, and excellent optical absorption and electrical properties of these CCO based nanomaterials are encouraging for the development of future applications in photoelectric devices.

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