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1.
Zhongguo Yi Liao Qi Xie Za Zhi ; 44(1): 60-64, 2020 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-32343069

RESUMO

Fluorescence imaging now becomes an intraoperative navigation technique that gaining popularity in surgery and clinical research. However, at present, there is no mature and reliable method or other related guidance documents for the detection of fluorescence imaging performance. The performance analysis and quality supervision of products on the market could not be performed, which affects their clinical use and image quality. In this paper, a standard method of fluorescence imaging performance testing for fluorescence imaging system is proposed. Several kinds of fluorescence imaging performance parameters affecting fluorescence images are defined strictly. We also recommend scientific and feasible methods for their detections and analyses, which are verified by practical examples. This paper aims to provide a feasible reference standard for fluorescence performance evaluation.

2.
Korean J Radiol ; 21(5): 550-560, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32323500

RESUMO

OBJECTIVE: To evaluate the interobserver agreement, diagnostic value, and associated clinical factors of automated breast ultrasound (ABUS) coronal features in differentiating breast lesions. MATERIALS AND METHODS: This study enrolled 457 pathologically confirmed lesions in 387 female (age, 46.4 ± 10.3 years), including 377 masses and 80 non-mass lesions (NMLs). The unique coronal features, including retraction phenomenon, hyper- or hypoechoic rim (continuous or discontinuous), skipping sign, and white wall sign, were defined and recorded. The interobserver agreement on image type and coronal features was evaluated. Furthermore, clinical factors, including the lesion size, distance to the nipple or skin, palpability, and the histological grade were analyzed. RESULTS: Among the 457 lesions, 296 were malignant and 161 were benign. The overall interobserver agreement for image type and all coronal features was moderate to good. For masses, the retraction phenomenon was significantly associated with malignancies (p < 0.001) and more frequently presented in small and superficial invasive carcinomas with a low histological grade (p = 0.027, 0.002, and < 0.001, respectively). Furthermore, continuous hyper- or hypoechoic rims were predictive of benign masses (p < 0.001), whereas discontinuous rims were predictive of malignancies (p < 0.001). A hyperechoic rim was more commonly detected in masses more distant from the nipple (p = 0.027), and a hypoechoic rim was more frequently found in large superficial masses (p < 0.001 for both). For NMLs, the skipping sign was a predictor of malignancies (p = 0.040). CONCLUSION: The coronal plane of ABUS may provide useful diagnostic value for breast lesions.

3.
Phys Chem Chem Phys ; 2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-32219230

RESUMO

In this study, the formation energies and electronic properties of six native defects as well as H impurities in wurtzite (wz) CdSe are systematically investigated using hybrid density functional calculations. It is shown that native defects, including antisite CdSe and interstitial Cdi, may be sources of the unintentional n-type conductivity in CdSe under Se-poor conditions; meanwhile, the vacancy defect VSe is not a good donor. However, when the common H impurity is considered, it is suggested that both the substitutional impurity HSe and the interstitial impurity Hi are the dominant and effective origins of the unintentional n-type conductivity in Se-poor conditions. However, unintentional p-type conductivity in CdSe is challenging to form regardless of the growth conditions. Moreover, hybrid functional calculations of the electronic structures show that the six native point defects and the extrinsic impurities Hi and HSe will cause more or fewer changes in the band gap. Among all considered defects and impurities, it is found that only the interstitial defect Cdi introduces impurity levels into the band gap. In particular, the present hybrid functional calculations theoretically affirm that the vacancy defect VCd in CdSe can induce a 2 µB magnetic moment; however, other native defects will not introduce any magnetic moment.

4.
Int J Cancer ; 2020 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-32064600

RESUMO

Although early detection and systemic therapies have improved the diagnosis and clinical cure rate of breast cancer, breast cancer remains the most frequently occurring malignant cancer in women due to a lack of sufficiently effective treatments. Thus, to develop potential targeted therapies and thus benefit more patients, it is helpful to understand how cancer cells work. ZIC family members have been shown to play important roles in neural development and carcinogenesis. In our study, we found that ZIC2 is downregulated in breast cancer tissues at both the mRNA and protein levels. Low expression of ZIC2 was correlated with poor outcome in breast cancer patients and serves as an independent prognostic marker. Furthermore, overexpression of ZIC2 repressed, whereas knockdown of ZIC2 promoted, cell proliferation and colony formation ability in vitro and tumor growth in vivo. Using ChIP-seq and RNA-seq analysis, we screened and identified STAT3 as a potential target for ZIC2. ZIC2 bound to the STAT3 promoter and repressed the promoter activities of STAT3. ZIC2 knockdown induced the expression of STAT3, increasing the level of phosphorylated STAT3. These results suggest that ZIC2 regulates the transcription of STAT3 by directly binding to the STAT3 promoter. Additionally, interfering STAT3 with siRNAs or inhibitors abrogated the oncogenic effects induced by decreased ZIC2. Taken together, our results indicate that ZIC2 serves as a useful prognostic marker in breast cancer and acts as a tumor suppressor by regulating STAT3, implying that STAT3 inhibitors might provide an alternative treatment option for breast cancer patients with ZIC2 downregulation.

5.
J Natl Cancer Inst ; 112(1): 55-62, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31093677

RESUMO

BACKGROUND: Taxane-induced peripheral neuropathy (TIPN) is a dose-limiting adverse effect. Ganglioside-monosialic acid (GM1) functions as a neuroprotective factor. We assessed the effects of GM1 on the prevention of TIPN in breast cancer patients. METHODS: We conducted a randomized, double-blind, placebo-controlled trial including 206 patients with early-stage breast cancer planning to receive taxane-based adjuvant chemotherapy with a follow-up of more than 1 year. Subjects were randomly assigned to receive GM1 (80 mg, day -1 to day 2) or placebo. The primary endpoint was the Functional Assessment of Cancer Treatment Neurotoxicity subscale score after four cycles of chemotherapy. Secondary endpoints included neurotoxicity evaluated by National Cancer Institute Common Terminology Criteria for Adverse Events Version 4.0 and the Eastern Cooperative Oncology Group neuropathy scale. All statistical tests were two-sided. RESULTS: In 183 evaluable patients, the GM1 group reported better mean Functional Assessment of Cancer Treatment Neurotoxicity subscale scores than patients in the placebo group after four cycles of chemotherapy (43.27, 95% confidence interval [CI] = 43.05 to 43.49 vs 34.34, 95% CI = 33.78 to 34.89; mean difference = 8.96, 95% CI = 8.38 to 9.54, P < .001). Grade 1 or higher peripheral neurotoxicity in Common Terminology Criteria for Adverse Events v4.0 scale was statistically significantly lower in the GM1 group (14.3% vs 100.0%, P < .001). Additionally, the GM1 group had a statistically significantly lower incidence of grade 1 or higher neurotoxicity assessed by Eastern Cooperative Oncology Group neuropathy scale sensory neuropathy (26.4% vs 97.8%, P < .001) and motor neuropathy subscales (20.9% vs 81.5%, P < .001). CONCLUSIONS: The treatment with GM1 resulted in a reduction in the severity and incidence of TIPN after four cycles of taxane-containing chemotherapy in patients with breast cancer.

6.
Chemosphere ; 242: 125207, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31675591

RESUMO

Landfills leachate contained diverse antibiotic resistance genes (ARGs). Treated landfill leachate effluent could enter into the downstream environments, leading to the dissemination of ARGs, which might pose a health risk to public. Here, we used high-throughput qPCR to characterize the resistome and 16S rRNA-based Illumina sequencing to analyze the bacterial community in a leachate treatment plant and the river near the landfill. A total of 91 ARGs and 5 mobile genetic elements were detected. Leachate treatment process significantly changed the profiles of resistome and bacterial community structures. Similar bacterial community structure and ARG profiles were detected between effluent and downstream river, which were both dominated by multidrug and beta-lactams resistance genes and harbored higher ARG relative abundance than that in upstream river. In particular, seven ARGs were detected both in effluent and downstream river samples but not detected in upstream river, including genes encoding resistance to vancomycin (vanXD and vanSB) and carbapenem (cphA and blaGES), which implied the effects of the effluent on its receiving river. This study highlights the risk of discharge of processed landfill leachate in dissemination of antibiotic resistance determinants to the environments, and suggests an urgent need for surveillance of ARGs and development of techniques to mitigate the risk.

7.
Org Lett ; 22(1): 140-144, 2020 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-31858804

RESUMO

We report an I2/FeCl3-co-promoted formal [2 + 2+1] annulation of aryl methyl ketones, 2-aminobenzyl alcohols, and p-toluenesulfonylmethyl isocyanide (TosMIC) by neighboring group (-CH2OH) assistance. This is a novel example of using the Van Leusen reagent as a unique C1N1 "two-atom synthon" in the synthesis of imidazoles. Preliminary mechanism studies showed that TsCH2NH2 might be the key intermediate in this reaction. Furthermore, this reaction not only unlocks a novel strategy for imidazole synthesis, but also exploits a new reactivity of TosMIC.

8.
Zhongguo Zhong Yao Za Zhi ; 44(22): 4781-4785, 2019 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-31872582

RESUMO

Molecular pharmacognosy( MP) is a new interdisciplinary science,which integrates the pharmacognosy and molecular biology,and focuses on the crude drugs' classification and identification,cultivation and protection,and production of active ingredients at the molecular level. Pogostemon cablin is one of the ten major southern medicines in China,MP research on this famous herb has developed on the basis of traditional research methods,and achieved certain results. This article summarized the MP research achievements of P. cablin in recent years,the prospect of this field is also discussed to provide references for the protection,development and utilization of P. cablin resources.


Assuntos
Lamiaceae , Farmacognosia , Pogostemon , China , Biologia Molecular
9.
J Org Chem ; 84(22): 14919-14925, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31612711

RESUMO

A molecular iodine-mediated coupling cyclization reaction for the synthesis of 4-aryl-NH-1,2,3-triazoles has been developed from N-tosylhydrazones and sodium azide. This metal-free cascade [4 + 1] cyclization reaction could rapidly synthesize valuable compounds via a sequential C-N and N-N bond formation. Mechanistic studies demostrate that the nitrogen atoms of the 1,2,3-triazoles are not entirely from sodium azide.

10.
Nat Commun ; 10(1): 4672, 2019 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-31611553

RESUMO

Naturally occurring chorus emissions are a class of electromagnetic waves found in the space environments of the Earth and other magnetized planets. They play an essential role in accelerating high-energy electrons forming the hazardous radiation belt environment. Chorus typically occurs in two distinct frequency bands separated by a gap. The origin of this two-band structure remains a 50-year old question. Here we report, using NASA's Van Allen Probe measurements, that banded chorus waves are commonly accompanied by two separate anisotropic electron components. Using numerical simulations, we show that the initially excited single-band chorus waves alter the electron distribution immediately via Landau resonance, and suppress the electron anisotropy at medium energies. This naturally divides the electron anisotropy into a low and a high energy components which excite the upper-band and lower-band chorus waves, respectively. This mechanism may also apply to the generation of chorus waves in other magnetized planetary magnetospheres.

11.
Org Lett ; 21(22): 8934-8937, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31664838

RESUMO

A highly efficient rongalite-mediated three-component radical annulation reaction to furnish fully substituted pyrazoles from aryldiazonium salts and α,ß-unsaturated aldehydes or ketones under metal- and oxidant-free conditions at room temperature has been developed. In this transformation, aryldiazonium salts served as the precursor of both the aryl and aryl hydrazine units. Mechanistic investigations indicated that rongalite could act as a radical initiator and reducing reagent simultaneously in the reaction.

12.
Org Lett ; 21(18): 7504-7508, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31486652

RESUMO

A novel and efficient formal [4 + 2+1] annulation of aryl methyl ketones and 2-aminobenzyl alcohols for the synthesis of benzo[e][1,4]diazepin-3-ones is reported. This reaction successfully affords diverse seven-membered ring lactams via dual C-O bond cleavage. A preliminary mechanistic study showed that a multicomponent dicyclization and ring-opening sequence might occur, with the introduction of methyl sulfide proposed as the last step. This efficient strategy with mild reaction conditions and a broad substrate scope has potential applications in chemistry and medicine.

13.
Environ Sci Technol ; 53(17): 10445-10453, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31373490

RESUMO

Combinations of metal(loid) contamination and antibiotics are considered to increase the abundance of resistance genes in the environment, whereas the combined effect of metal(loid)s and antibiotics on microbial communities and antibiotic resistance genes (ARGs) in the gut of soil fauna remains unknown. We investigated herein the alteration of ARGs and the gut microbial communities after the earthworm Metaphire sieboldi was exposed to arsenate and/or sulfamethoxazole using high-throughput quantitative PCR and Illumina sequencing analysis. Arsenic accumulation in the body tissues of arsenic-exposed earthworms exerted a significant inhibition on growth and survival. The synergistic interactions of arsenic and sulfamethoxazole increased significantly the incidence of ARGs and mobile genetic elements in the earthworm gut microbiota. In addition, co-exposure to arsenic and sulfamethoxazole altered the structure of the gut microbial communities, and the changes correlated with ARG profiles of the gut microbiota. Our results indicate that the gut of soil fauna is a neglected hotspot of antibiotic resistance.


Assuntos
Arsênico , Oligoquetos , Animais , Antibacterianos , Resistência Microbiana a Medicamentos , Genes Bacterianos , Incidência , Sulfametoxazol
14.
Cancer Manag Res ; 11: 5489-5499, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31354355

RESUMO

Background: Large-cell lung carcinomas (LCLCs) were reclassified by the World Health Organization 2015 criteria. and remain fairly unknown at the molecular level and targeted-therapeutic options. Methods: Data of 184 lung cancer patients were retrieved from clinical records, of which 54 were found to be pathologically diagnosed as LCLC. The genetic alterations EGFR/KRAS/BRAF mutations, MET copy number, and exon 14 mutation, ALK and ROS1 rearrangements, and PDL1 expression were investigated using clinical technologies. The relationship between clinicopathologic and genetic features was analyzed, and the Kaplan-Meier method with log-rank test was used for analyzing patient survival. Results: Major events, including EGFR, KRAS, and BRAF mutations and MET copy-number gain, were found in 5.6%, 16.7%, 1.9%, and 18.5% in LCLC, respectively. No ALK or ROS1 translocation was detected. PDL1 expression in tumor cells and in tumor-infiltrating lymphocytes was observed in 24 (44.4%) and 16 (29.6%) patients. Kaplan-Meier analysis showed that patients with a KRAS mutation had ower 5-year overall survival than those with wild-type KRAS (25.4% vs 47.8%, P=0.028) and that patients with negative PDL1 stained in tumor cells but positive for tumor-infiltrating lymphocytes had significantly favorable overall survival compared to those with solitary and positive PDL1 stained in tumor cells (62.5% vs 20.6%, P=0.044). Conclusion: KRAS mutations and PDL1 expression can predict patient survival and be potential target options in LCLC.

15.
Chem Commun (Camb) ; 55(56): 8134-8137, 2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31240291

RESUMO

An efficient I2/CuCl2-promoted one-pot three-component strategy for the construction of 1,2,3-thiadiazoles from aliphatic- or aromatic-substituted methyl ketones, p-toluenesulfonyl hydrazide, and potassium thiocyanate has been developed. Simple and commercially available starting materials, a broad substrate scope, and excellent functional group tolerability make this strategy practical for applications. Furthermore, 1,2,3-thiadiazole synthesis was realized by using potassium thiocyanate as an odorless sulfur source.

16.
Org Lett ; 21(13): 4939-4943, 2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-31247767

RESUMO

A N-H/α,ß-C(sp3)-trifunctionalization of l-proline, proceeding through an iodine-promoted consecutive decarboxylation/ring-opening/dicyclization process, is achieved. This strategy affords structurally diverse fused N-heterocycles in good yields with a wide substrate scope. Preliminary mechanistic studies indicate that catabolism of l-proline might be involved in this cascade reaction and the in situ generated intermediate 4-aminobutanal was identified as the key intermediate. Notably, this domino strategy enriches the reactivity of versatile l-proline in the synthesis of fused heterocycles.

17.
Sci Total Environ ; 683: 210-215, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31132699

RESUMO

Heavy metal induced co-selection of antibiotic resistance genes (ARGs) has become an emerging environmental issue. The guts of soil fauna offer a unique habitat in the terrestrial ecosystem and harbor a variety of microorganisms. However, the effects of heavy metals on the gut-associated ARGs of soil fauna are poorly understood. In the present study, collembolans were cultivated with four types of heavy metals (Zn, Cu, Cd, and Cr) and one antibiotic (oxytetracycline), to investigate their impact on the gut-associated ARGs. High-throughput quantitative PCR and 16S rRNA gene amplicon sequencing were used to examine changes in the gut-associated ARGs and microbial composition caused by the metals and antibiotic. The results showed that heavy metals alone induced co-selection of ARGs in the collembolan gut, but the effects were weaker than selection by oxytetracycline. When Zn or Cu was present together with oxytetracycline, there was a strong synergistic effect between the compounds, which increased the selection of ARGs in the collembolan guts. Furthermore, redundancy analysis revealed that the gut microbiota and mobile genetic elements (MGEs) were significantly correlated with the ARG composition. These results extend our understanding on effects of heavy metals on the dispersal of ARGs in the soil food web.


Assuntos
Artrópodes/genética , Resistência Microbiana a Medicamentos/genética , Microbioma Gastrointestinal/genética , Metais Pesados/toxicidade , Seleção Genética/efeitos dos fármacos , Animais , Antibacterianos/farmacologia , Artrópodes/efeitos dos fármacos , Microbioma Gastrointestinal/efeitos dos fármacos , Oxitetraciclina/farmacologia
18.
J Org Chem ; 84(12): 8322-8329, 2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31140280

RESUMO

An I2/PhI(OAc)2 copromoted strategy using dimethyl sulfoxide as an "S/C2/O" source for preparing α-dicarbonylsulfoximine derivatives is reported. This process involves oxidative coupling to construct a C-N bond and electrophilic amination of dimethyl sulfoxide to afford an N═S bond, with dimethyl sulfoxide present in the final product as an intact molecule. Furthermore, tetramethylene sulfoxide as a solvent is also compatible with this amination reaction.

19.
Pest Manag Sci ; 75(11): 2873-2881, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31038279

RESUMO

BACKGROUND: With the growing number of available aphid genomes and transcriptomes, an efficient and easy-to-adapt tool for gene function study is urgently required. RNA interference (RNAi), as a post-transcriptional gene silencing mechanism, is important as a research tool for determining gene functions and has potential as a novel insect control strategy. However, these applications have been hampered by the lack of effective dsRNA delivery approaches in aphids. RESULTS: Here, we developed a convenient and efficient dsRNA delivery method, topical RNAi, in aphids. An investigation of its dose and time-dependent RNAi efficiencies revealed that with as little as 60 ng dsRNA per adult pea aphid (Acyrthosiphon pisum), the indicator gene, Aphunchback, could be significantly silenced within 2 h of exposure. The method was further validated by successfully silencing other different genes, and it was also efficient toward two other aphid species, Aphis citricidus and Myzus persicae. Furthermore, a noticeable mortality was also observed in pea aphids using topical RNAi-mediated gene silencing, within 4 days post-dsRNA application for four out of seven tested genes. CONCLUSION: Compared with the currently used dsRNA delivery methods in aphids, microinjection and ingestion, topical RNAi is time- and cost-effective, which could greatly influence RNAi-based gene functional studies and potential candidate gene selection for developing RNAi-based aphid control strategies in the future. © 2019 Society of Chemical Industry.


Assuntos
Afídeos/genética , Inativação Gênica , Genes de Insetos , RNA de Cadeia Dupla/farmacologia , Animais , RNA de Cadeia Dupla/administração & dosagem
20.
Environ Int ; 128: 399-406, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31078874

RESUMO

Growing evidences have demonstrated that heavy metal contamination can promote the proliferation of antibiotic resistance genes (ARGs) via co-selection. However, effects of nano-metal-materials on the occurrence and level of ARGs in the soil and plant, have not been fully explored. To gain insights into this impact, we conducted a pot experiment by adding nano­silver particles (AgNPs) as a stimuli and Ag ion (AgNO3) and tetracycline as a comparison. By using high throughput quantitative PCR, our results indicated that application of AgNPs (~20 nm and ~50 nm) at a concentration of 100 ppm resulted in no significant changes in the abundance of ARGs in either soil or phyllosphere (P > 0.05). Nevertheless, the overall pattern of resistome, especially in soil, was shifted following AgNPs application, with a significance increase in the relative abundance of efflux pumps genes, which is an important mechanism for co-selection of ARGs by heavy metals. By comparison, Ag ion at an equivalent Ag mass of AgNPs markedly increased ARGs abundance and shifted ARGs profile in soil, indicating that free Ag ion had a stronger impact on ARGs than AgNPs. These findings provide new insights in assessing the risks of manufactured nanomaterials accumulated in the environment.


Assuntos
Bactérias/efeitos dos fármacos , Coriandrum/microbiologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Nanopartículas Metálicas , Seleção Genética/efeitos dos fármacos , Prata/farmacologia , Bactérias/genética , Farmacorresistência Bacteriana/genética , Microbiologia do Solo
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