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1.
J Am Chem Soc ; 2020 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-32402194

RESUMO

While positively charged nanomaterials induce cytotoxicity in many organisms, much less is known about how the spatial distribution and presentation of molecular surface charge impacts nanoparticle-biological interactions. We systematically functionalized diamond nanoparticle surfaces with five different cationic surface molecules having different molecular structures and conformations, including four small ligands and one polymer, and we then probed the molecular-level interaction between these nanoparticles and bacterial cells. Shewanella oneidensis MR-1 was used as a model bacterial cell system to investigate how molecular length and conformation of cationic surface charges influence their interactions with the Gram-negative bacterial membranes. Nuclear magnetic resonance (NMR) and X-ray photoelectron spectroscopy (XPS) demonstrate the covalent modification of nanoparticle surface with the desired cationic organic monolayers. Surprisingly, bacterial growth-based viability (GBV) and membrane damage assays both show only minimal biological impact by the NPs functionalized with short cationic ligands within the concentration range tested. Yet NPs covalently linked to a cationic polymer induce strong cytotoxicity, including reduced cellular viability and significant membrane damage at the same concentration of cationic groups. Transmission electron mi-croscopy (TEM) images of these NP-exposed bacterial cells show that NPs functionalized with cationic polymers induce significant membrane distortion and production of outer membrane vesicles, while NPs bearing short cationic ligands exhibit only weak membrane association. Our results demonstrate that the spatial distribution of molecular charge plays a key role in controlling the interaction of cationic nanoparticles with bacterial cell membranes and subsequent biological impact. Nanoparticles functionalized with ligands having different lengths and conformations can have large differences in interactions even while having nearly identical zeta potentials. While zeta potential is a convenient and commonly used measure of nanoparticle charge, it does not capture essential differences in molecular-level nanoparticle properties that control their biological impact.

4.
Eur Rev Med Pharmacol Sci ; 24(9): 5176-5177, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32432783

RESUMO

OBJECTIVE: COVID-19 broke out in China at the end of 2019 and spread rapidly around the world. The World Health Organization designated COVID-19 as a global pandemic on March 11, 2020. China has adopted its own country-specific comprehensive prevention and control measures, and, as a result, the domestic COVID-19 epidemic became effectively controlled in China in mid-March 2020. During the COVID-19 epidemic, remarkable changes have taken place in China's domestic learning, living, and working methods, primarily in terms of the synergy between the Internet Plus (Internet+) strategy and the leadership of the Chinese government.

8.
Eur Rev Med Pharmacol Sci ; 24(6): 3397-3399, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32271457

RESUMO

On December 31, 2019, the World Health Organization (WHO) reported a cluster of cases of pneumonia of unknown cause detected in Wuhan City, Hubei Province, China. As of February 29, 2020, the National Health Commission of China has reported 79,389 confirmed cases of SARS-CoV-2 infection in 34 provinces. The masks can be used to block respiratory transmission from human to human, and are an effective way to control influenza. It is, therefore, necessary to wear a mask when respiratory infectious diseases are prevalent. China has a population of 1.4 billion. Assuming that two-thirds of the people in China must wear a mask every day, the daily demand for masks will reach 900 million. The Chinese government has taken many measures to solve these problems. Additionally, more measures should be taken to properly dispose of mask garbage. Although the outbreak originated in China, person-to-person transmission of SARS-CoV-2 has been confirmed, which means that it can be spread to anywhere in the world if prevention measures fail. The issues regarding face mask shortages and garbage in China, therefore, deserve worldwide attention.


Assuntos
Betacoronavirus , Infecções por Coronavirus/prevenção & controle , Surtos de Doenças , Máscaras/provisão & distribução , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/transmissão , Humanos , Pneumonia Viral/epidemiologia , Pneumonia Viral/transmissão
9.
Int Endod J ; 2020 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-32189340

RESUMO

AIM: The objectives of this laboratory-based study were to investigate the effects of GH12 on Enterococcus faecalis biofilm and virulence. METHODOLOGY: Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of GH12 against E. faecalis were first determined. A time-kill assay was further conducted. The effects of GH12 on the expression of virulence and stress genes in E. faecalis were evaluated by RT-qPCR. Crystal violet stain was used to investigate the effects of GH12 on E. faecalis biofilm formation and 1-day-old biofilm. Finally, an ex vivo tooth model contaminated with E. faecalis was used to evaluate the antimicrobial activity of GH12 as an irrigant by CFU counting, SEM and CLSM. One-way anova and Tukey's multiple comparisons test were used to compare the differences amongst groups (α = 0.05). RESULTS: The MICs and MBCs of GH12 against E. faecalis were 8.0 ± 0.0 and 16.0 ± 0.0 mg L-1 , respectively, and GH12 at 32.0 mg L-1 reduced the bacterial numbers by more than 99.9% within 1 min. Various virulence genes (efaA, esp and gelE) and stress genes (dnaK, groEL, ctsR and clpPBCEX) in E. faecalis were significantly downregulated by GH12 at sub-MIC levels (P < 0.05). Additionally, both E. faecalis biofilm formation and the biomass of 1-day-old E. faecalis biofilm were significantly reduced by GH12 (P < 0.05). Elimination of E. faecalis in biofilms from root canal walls was achieved through irrigation with 64.0 mg L-1 GH12 for 30 min. CLSM analysis revealed that GH12 at 64.0 mg L-1 was most effective in eliminating bacteria within dentinal tubules (P < 0.05). CONCLUSION: In a laboratory setting, and when used as an irrigant, GH12 suppressed E. faecalis, downregulated specific virulence and stress-associated genes, eliminated intracanal E. faecalis protected by biofilms and killed bacteria in dentinal tubules. These results emphasize the need for preclinical and clinical studies to explore the potential of GH12 as an antimicrobial agent during root canal treatment.

10.
Zhonghua Yi Xue Za Zhi ; 100(7): 527-532, 2020 Feb 25.
Artigo em Chinês | MEDLINE | ID: mdl-32164105

RESUMO

Objective: To compare the effect of different supraorbital foramen variations on the clinical efficacy of radiofrequency treatment of primary trigeminal neuralgia V1. Methods: The clinical data of 62 patients with primary trigeminal neuralgia (V1 branch) from February 2011 to August 2017 in the first hospital of Jiaxing were analyzed retrospectively. According to the shape of supraorbital foramen, the patients were divided into foramen group (n=28) and incisional group (n=34). The age, sex, course time, CT scan times of the two groups were recorded, and the mean rank of NRS scores and effective rates (NRS≤1) before operation, 1 day after operation, 6 months after operation, 1 year after operation and 2 years after operation were statistically analyzed, as well as the difference of numbness degree in 1 day and 2 years after operation. The short-term and long-term complications were recorded. Results: There was no significant difference in age, gender, course time, CT scan times, preoperative NRS and postoperative NRS between the two groups (P>0.05). Compared with the preoperative, the mean rank of NRS in the two groups decreased significantly at each postoperative time point, and the difference was statistically significant (all P<0.05). Foramen group of postoperative 1 d Ⅰ, Ⅱ, Ⅲ, Ⅳ numbness rate were 0, 53.6%, 46.4% and 0 respectively, after 2 years were 42.9%, 46.4%, 10.7% and 0 respectively. Incisional group of postoperative 1 d Ⅰ, Ⅱ, Ⅲ, Ⅳ numbness rate were 0, 29.4%, 67.6% and 2.9% respectively, after 2 years were 55.9%, 38.2%, 5.9% and 0 respectively. The degree of numbness 2 years after the operation was reduced in both groups compared with that 1 day after the operation, and the difference was statistically significant (all P<0.05). The effective rates of the foramen group and the incisional group were 78.6% and 52.9%, respectively, with statistically significant differences (χ(2)=4.406, P<0.05) . The patient had no other serious complications in the near and long term except for the swelling of puncture point. Conclusion: The short and long-term effective rates of supraperitoneal foramen in anatomical variants for the radiofrequency treatment of primary trigeminal neuralgia V1 are higher. The supraorbital foramen have higher long-term effective rates, there are no other serious adverse reactions excepting numbness, and the patients have a higher acceptability.


Assuntos
Tratamento por Radiofrequência Pulsada , Neuralgia do Trigêmeo , Eletrocoagulação , Humanos , Estudos Retrospectivos , Resultado do Tratamento , Neuralgia do Trigêmeo/terapia
12.
Chem Res Toxicol ; 33(3): 806-816, 2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-32013395

RESUMO

Cobalt phosphate engineered nanomaterials (ENMs) are an important class of materials that are used as lithium ion battery cathodes, catalysts, and potentially as super capacitors. As production of these nanomaterials increases, so does the likelihood of their environmental release; however, to date, there are relatively few investigations of the impact of nanoscale metal phosphates on biological systems. Furthermore, nanomaterials used in commercial applications are often multiphase materials, and analysis of the toxic potential of mixtures of nanomaterials has been rare. In this work, we studied the interactions of two model environmental bacteria, Shewanella oneidensis MR-1 and Bacillus subtilis, with a multiphase lithiated cobalt phosphate (mLCP) nanomaterial. Using a growth-based viability assay, we found that mLCP was toxic to both bacteria used in this study. To understand the observed toxicity, we screened for production of reactive oxygen species (ROS) and release of Co2+ from mLCP using three abiotic fluorophores. We also used Newport Green DCF dye to show that cobalt was taken up by the bacteria after mLCP exposure. Using transmission electron microscopy, we noted that the mLCP was not associated with the bacterial cell surface. In order for us to further probe the mechanism of interaction of mLCP, the bacteria were exposed to an equivalent dose of cobalt ions that dissolved from mLCP, which recapitulated the changes in viability when the bacteria were exposed to mLCP, and it also recapitulated the observed bacterial uptake of cobalt. Taken together, this implicates the release of cobalt ions and their subsequent uptake by the bacteria as the major toxicity mechanism of mLCP. The properties of the ENM govern the release rate of cobalt, but the toxicity does not arise from nanospecific effects-and importantly, the chemical composition of the ENM may dictate the oxidation state of the metal centers and thus limit ROS production.

13.
Zhonghua Yu Fang Yi Xue Za Zhi ; 54(3): 239-244, 2020 Mar 06.
Artigo em Chinês | MEDLINE | ID: mdl-32064856

RESUMO

In December 2019, novel coronavirus pneumonia epidemic occurred in Wuhan, Hubei Province, and spread rapidly across the country. In the early stages of the epidemic, China adopted the containment strategy and implemented a series of core measures around this strategic point, including social mobilization, strengthening case isolation and close contacts tracking management, blocking epidemic areas and traffic control to reduce personnel movements and increase social distance, environmental measures and personal protection, with a view to controlling the epidemic as soon as possible in limited areas such as Wuhan. This article summarizes the background, key points and core measures in the country and provinces. It sent prospects for future prevention and control strategies.


Assuntos
Controle de Doenças Transmissíveis/métodos , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Betacoronavirus , China , Busca de Comunicante , Humanos , Quarentena
14.
Zhonghua Yi Xue Za Zhi ; 100(3): 178-181, 2020 Jan 21.
Artigo em Chinês | MEDLINE | ID: mdl-32008282

RESUMO

Objective: To evaluate the classification of the types of pediatric posterior fossa brain tumors based on routine MRI (T(1)WI, T(2)WI and ADC) using wavelet transformation analysis of whole tumor. Methods: MRI images of medulloblastoma (n=59), ependymoma (n=13) and pilocytic astrocytoma (n=27) confirmed by pathology before treatments in Children's Hospital of Nanjing Medical University from January 2014 to February 2019 were enrolled in this retrospective study as well as the clinical data of age, gender and symptoms. Registration was performed among the three sequences and wavelet features of ROI were acquired. Afterwards, the top ten features were ranked and trained among groups by using random forest classifier. Finally, the results were compared and analyzed according to the classification. Results: The top ten contribution three sequences and wavelet features of ROI were acquired from the ADC sequence. The random forest classifier achieved 100% accuracy on training data and was validated best accuracy (86.8%) when combined of first and third wavelet features. The sensitivity was 100%, 94.8%, 76.9%, and the specificity was 97.6%, 88.0%, 98.8% respectively. Conclusions: Features based on wavelet transformation of ADC sequence of entire tumor can provide more quantitative information, which could provide help in the differential diagnosis of pediatric posterior fossa brain tumors. The optimum combination to distinguish three pediatric posterior fossa brain tumors is sixth and twelfth wavelet features of ADC sequence.


Assuntos
Astrocitoma/classificação , Neoplasias Cerebelares/patologia , Neoplasias Infratentoriais/patologia , Imagem por Ressonância Magnética/métodos , Meduloblastoma/classificação , Astrocitoma/patologia , Neoplasias Encefálicas/patologia , Criança , Humanos , Meduloblastoma/patologia , Estudos Retrospectivos
15.
Eur Rev Med Pharmacol Sci ; 23(22): 9840-9847, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31799651

RESUMO

OBJECTIVE: Hepatocellular carcinoma (HCC) is one of the most common malignant tumors. Long noncoding RNAs (lncRNAs) play important roles in many diseases. Therefore, the aim of this study was to investigate the role of lncRNA ZFAS1 in the development of HCC and to explore its underlying mechanism. PATIENTS AND METHODS: Real Time-quantitative Polymerase Chain Reaction (RT-qPCR) was utilized to detect ZFAS1 expression in tissue samples of HCC patients. Subsequently, Cell Counting Kit-8 (CCK-8) assay, colony formation assay, and EdU incorporation assay were performed to detect the function of ZFAS1 in vitro. Furthermore, mechanism assays were performed to explore the interaction between ZFAS1 and miR-193a-3p. RESULTS: ZFAS1 was significantly highly expressed in HCC tissues than that of adjacent normal tissues. The growth ability of HCC cells was markedly inhibited after ZFAS1 was silenced. However, the growth ability of HCC cells was remarkably promoted after ZFAS1 overexpression. Moreover, RT-qPCR results revealed that miR-193a-3p was significantly down-regulated via the overexpression of ZFAS1. However, miR-193a-3p was significantly up-regulated via the knockdown of ZFAS1. Further experiments showed that miR-193a-3p was a direct target of ZFAS1 in HCC. CONCLUSIONS: ZFAS1 could enhance the proliferation of HCC cells by suppressing miR-193a-3p, which might be a potential therapeutic target in HCC.

16.
Zhonghua Yu Fang Yi Xue Za Zhi ; 53(10): 961-963, 2019 Oct 06.
Artigo em Chinês | MEDLINE | ID: mdl-31607037

RESUMO

This year of 2019 is the 10(th) anniversary of the 2009 H1N1 influenza pandemic, and a series of paper on epidemiology, disease burden, vaccine usage and adverse events following immunization (AEFI) incidences, cost-effectiveness of influenza vaccination, are forming an important topic of "influenza disease burden and vaccine policies" in this journal, which provide evidences and options for China's influenza prevention and control. We should continue to strengthen the operational researches on influenza prevention and control polices, increase the influenza vaccine coverage in high-risk groups, and improve the capacities of control and pandemic preparedness.


Assuntos
Promoção da Saúde , Vacinas contra Influenza , Influenza Humana , Vacinação , China , Humanos , Vírus da Influenza A Subtipo H1N1 , Polícia
17.
Environ Sci Nano ; 6(1): 305-314, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31572614

RESUMO

The wide applications of lithium intercalating complex metal oxides in energy storage devices call for a better understanding of their environmental impact at the end of their life cycle. In this study, we examine the biological impact of a panel of nanoscale lithium nickel manganese cobalt oxides (Li x Ni y Mn z Co1-y-z O2, 0 < x, y, z < 1, abbreviated to NMCs) to a model Gram-positive bacterium, Bacillus subtilis, in terms of cellular respiration and growth. A highly sensitive single-cell gel electrophoresis method is also applied for the first time to understand the genotoxicity of these nanomaterials to bacterial cells. Results from these assays indicate that the free Ni and Co ions released from the incongruent dissolution of the NMC material in B. subtilis growth medium induced both hindered growth and cellular respiration. More remarkably, the DNA damage induced by the combination of the two ions in solution is comparable to that induced by the NMC material, which suggests that the free Ni and Co ions are responsible for the toxicity observed. A material redesign by enriching Mn is also presented. The combined approaches of evaluating their impact on bacterial growth, respiration, and DNA damage at a single-cell level, as well as other phenotypical changes allows us to probe the nanomaterials and bacterial cells from a mechanistic prospective, and provides a useful means to an understanding of bacterial response to new potential environmental stressors.

18.
Zhonghua Shao Shang Za Zhi ; 35(10): 740-745, 2019 Oct 20.
Artigo em Chinês | MEDLINE | ID: mdl-31658545

RESUMO

Objective: To construct and identify a mouse model with conditional knockout (cKO) of p75 neurotrophin receptor (p75NTR-cKO) gene in epidermis cells by Cre-loxP system. Methods: Five p75NTR(flox/flox) transgenic C57BL/6J mice (aged 6-8 weeks, male and female unlimited, the age and sex of mice used for reproduction were the same below) and five keratin 14 promotor-driven (KRT14-) Cre(+ /-) transgenic C57BL/6J mice were bred and hybridized via Cre-loxP system. Five p75NTR(flox/+) ·KRT14-Cre(+ /-) mice selected from the first generation of mice were mated with five p75NTR(flox/flox) mice to obtain the second generation hybrids. After the second generation mice were born 20-25 days, the parts of the mice tail were cut off to identify the genotype by polymerase chain reaction method. Four p75NTR gene complete cKO mice (6 weeks old) and 4 wild-type mice (6 weeks old) were selected and sacrificed respectively. The abdominal skin tissue and brain tissue were excised to observe the expression of p75NTR in the two tissue of two types of mice by immunohistochemical staining. The abdominal skin tissue of two types of mice was obtained to observe the histomorphological changes by hematoxylin and eosin staining. Results: (1) Twenty second generation mice were bred. The genotype of 4 mice was p75NTR(flox/flox)·KRT14-Cre(+ /-)(p75NTR(-/-)), i. e. p75NTR gene complete cKO mice; the genotype of 5 mice was p75NTR(flox/+) ·KRT14-Cre(+ /-), i. e. p75NTR gene partial cKO mice; the genotype of 5 mice was p75NTR(flox/flox)·KRT14-Cre(-/-), and that of 6 mice was p75NTR(flox/+) ·KRT14-Cre(-/-), all of which were wild-type mice. (2) The expression of p75NTR was negative in skin epidermis tissue of p75NTR gene complete cKO mice, while numerous p75NTR positive expression was observed in skin epidermis tissue of wild-type mice. Abundant p75NTR positive expression was observed in brain tissue of both wild-type mice and p75NTR gene complete cKO mice. (3) There was no abnormal growth of skin epidermis tissue in both wild-type mice and p75NTR gene complete cKO mice, with intact hair follicle structure. Conclusions: Applying Cre-loxP system can successfully construct a p75NTR-cKO mice model in epidermis cells without obvious changes in skin histomorphology.


Assuntos
Células Epidérmicas , Folículo Piloso/crescimento & desenvolvimento , Receptor de Fator de Crescimento Neural , Animais , Feminino , Folículo Piloso/metabolismo , Integrases , Queratina-14 , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
19.
Phys Rev Lett ; 123(5): 051101, 2019 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-31491288

RESUMO

We report on the highest energy photons from the Crab Nebula observed by the Tibet air shower array with the underground water-Cherenkov-type muon detector array. Based on the criterion of a muon number measured in an air shower, we successfully suppress 99.92% of the cosmic-ray background events with energies E>100 TeV. As a result, we observed 24 photonlike events with E>100 TeV against 5.5 background events, which corresponds to a 5.6σ statistical significance. This is the first detection of photons with E>100 TeV from an astrophysical source.

20.
Eur Rev Med Pharmacol Sci ; 23(17): 7350-7355, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31539121

RESUMO

OBJECTIVE: The role of long noncoding RNAs (lncRNAs) is vital in tumor progression. Our study aims to identify the role of PCAT-1 in the metastasis of pancreatic cancer. PATIENTS AND METHODS: Real time-quantitative polymerase chain reaction (RT-qPCR) was used to measure PCAT-1 expression in 50 pancreatic cancer patients' tissues. Furthermore, to identify the function of PCAT-1 in pancreatic cancer in vitro wound healing assay and transwell assay were conducted. Besides, RT-qPCR and Western blot assay were performed to explore the underlying mechanism. RESULTS: The expression level of PCAT-1 was significantly upregulated in pancreatic cancer samples compared with adjacent tissues. Moreover, cell migration and cell invasion were inhibited via knockdown of PCAT-1 in pancreatic cancer cells. Moreover, the mRNA and protein expression of RBM5 was upregulated via knockdown of PCAT-1 in pancreatic cancer cells. Furthermore, the RBM5 expression level was negatively related to the PCAT-1 expression level in pancreatic cancer tissues. CONCLUSIONS: This study suggests that PCAT-1 acts as an oncogene in pancreatic cancer and promotes cell metastasis via inhibiting RBM5, which might be a novel therapeutic strategy in pancreatic cancer.

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