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1.
Environ Toxicol ; 2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-32167222

RESUMO

Glyburide is a classic antidiabetic drug that is dominant in inflammation regulation, but its specific role in ozone-induced lung inflammation and injury remains unclear. In order to investigate whether glyburide prevents ozone-induced pulmonary inflammation and its mechanism, C57BL/6 mice were intratracheally pre-instilled with glyburide or the vehicle 1 hour before ozone (1 ppm, 3 hours) or filtered air exposure. After 24 hours, the total inflammatory cells and total protein in bronchoalveolar lavage fluid (BALF) were detected. The pathological alternations in lung tissues were evaluated by HE staining. The expression of NLRP3, interleukin-1ß (IL-1ß), and IL-18 protein in lung tissues was detected by immunohistochemistry. Western blotting was used to examine the levels of caspase-1 p10 and active IL-1ß protein. Levels of IL-1ß and IL-18 in BALF were measured using ELISA kits. Glyburide treatment decreased the total cells in BALF, the inflammatory score, and the mean linear intercept induced by ozone in lung tissues. In addition, glyburide inhibited the expression of NLRP3, IL-18, and IL-1ß protein in lung tissues, and also suppressed NLRP3 inflammasome activation, including caspase-1 p10, active IL-1ß protein in lung tissues, IL-1ß, and IL-18 in BALF. These results demonstrate that glyburide effectively attenuates ozone-induced pulmonary inflammation and injury via blocking the NLRP3 inflammasome.

2.
J Med Virol ; 92(3): 372-381, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31670402

RESUMO

Human papillomavirus (HPV)16 gene mutation is usually associated with persistent HPV infection and cervical intraepithelial neoplasia (CIN). However, the functional implications of HPV16 mutations remain poorly understood.145 LCR/E6/E7 of the HPV16 isolates were amplified and sequenced, and HPV16 integration status was detected. In total, 89 SNPs (68 in the LCR, 13 in E6, 8 in E7) were discovered, 11 of which were nonsynonymous mutations (8 in E6, 3 in E7). The H85Y and E120D variants in E6 were significantly reduced in the high-grade squamous intraepithelial lesion (HSIL) group compared to the T," a potential binding site for TATA-binding protein, is the most common in LCR variants. A4 (Asian) was associated with an increased risk of HSIL compared to A1-3(P = .009). The H85/E120 in E6 and N29 in HPV16 E7 might play a critical role in carcinogenesis by disrupting p53 and Rb degradation due to affecting their interaction, respectively. In a word, the findings in this study provide preventative and therapeutic interventions of HPV16 -related cervical lesions/cancer.

3.
Opt Express ; 27(21): 31094-31109, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31684349

RESUMO

An ultra-compact concentric catadioptric imaging spectrometer with large relative aperture and long slit is proposed. It consists of three optical components integrated monolithically in a concentric layout. Its astigmatism theory is discussed through tracing its chief ray and its athermalization is realized by optimizing lens materials. A high-speed (F/2.25) long-slit (48mm) VNIR design with high imaging quality and small distortions is presented. Results show a 10× reduction in volume than classic designs based on Offner-Chrisp configuration and a 1.9× reduction in length than Dyson configuration. Moreover, the design shows superior thermal adaptability with negligible decline in imaging quality while operating temperature changes between -30 ℃ and 70 ℃.

4.
Nanoscale ; 11(39): 18320-18328, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31573013

RESUMO

Plasmonic metal nanocatalysts have excellent light trapping properties and high chemical reactivity. Impressively, Au nanostructures can absorb a wide array of visible light by tuning their morphology. In this work, spherical gold nanoparticles (Au NSs), multi-branched gold nanoparticles (Au NMs) and gold nanorods (Au NRs) were successfully synthesized; the shape- and size-dependences of these gold nanocatalysts on the methanol oxidation reaction (MOR) under light irradiation were studied. It is worth mentioning that Au NRs have the highest anode peak current density under dark conditions due to the exposure of highly active facets. A similar enhancement effect was obtained for Au NSs and Au NMs under visible light irradiation, which is due to the generation of a high concentration of energetic charge carriers on these Au nanostructures. The size dependences of Au NSs on the MOR showed that a larger electrochemically active surface area (ECSA) was obtained for small nanoparticles, which is due to the surface effect. In addition, the catalytic performance, durability and anti-CO stripping of these Au nanocatalysts under visible light irradiation, as well as the effect of light intensity and wavelength were described in detail. This work provides an insight into the mechanism of plasmon enhanced electrocatalysis by Au nanostructures with different sizes and shapes.

5.
Nat Cell Biol ; 21(6): 687-699, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31160711

RESUMO

We recently derived mouse expanded potential stem cells (EPSCs) from individual blastomeres by inhibiting the critical molecular pathways that predispose their differentiation. EPSCs had enriched molecular signatures of blastomeres and possessed developmental potency for all embryonic and extra-embryonic cell lineages. Here, we report the derivation of porcine EPSCs, which express key pluripotency genes, are genetically stable, permit genome editing, differentiate to derivatives of the three germ layers in chimeras and produce primordial germ cell-like cells in vitro. Under similar conditions, human embryonic stem cells and induced pluripotent stem cells can be converted, or somatic cells directly reprogrammed, to EPSCs that display the molecular and functional attributes reminiscent of porcine EPSCs. Importantly, trophoblast stem-cell-like cells can be generated from both human and porcine EPSCs. Our pathway-inhibition paradigm thus opens an avenue for generating mammalian pluripotent stem cells, and EPSCs present a unique cellular platform for translational research in biotechnology and regenerative medicine.


Assuntos
Diferenciação Celular/genética , Reprogramação Celular/genética , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes/citologia , Animais , Blastômeros/citologia , Blastômeros/metabolismo , Linhagem da Célula/genética , Células-Tronco Embrionárias/citologia , Camadas Germinativas/crescimento & desenvolvimento , Camadas Germinativas/metabolismo , Humanos , Camundongos , Medicina Regenerativa , Transdução de Sinais/genética , Suínos , Trofoblastos/citologia , Trofoblastos/metabolismo
6.
Anal Chim Acta ; 1022: 131-137, 2018 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-29729733

RESUMO

In this study, a system was established for the detection of tetracyclines (TCs) by simply mixing graphene quantum dots (GQDs) and Eu3+. The GQDs-Eu3+ system exhibits both strong emission of GQDs and weak characteristic emission of Eu3+ upon 360 nm excitation. In the presence of TCs, the luminescence of GQDs was quenched, while the luminescence of Eu3+ was significantly enhanced. It is worth to mention that the GQDs we prepared possess a lot of carboxyl groups on the surface and edge. This carboxyl groups play an important role in fluorescent enhancement of Eu3+. On the basis of this effect, a novel label free ratiometric sensor was developed for the detection of TCs. Under the optimized conditions, linear concentration ranges from 0 to 20 µM for tetracycline was found, and the detection limits was 8.2 nM. This system also exhibited excellent selectivity toward TCs over other antibiotics. In addition, it was successfully applied to the determination of tetracycline in river water and milk samples. The proposed system was simple in design, fast in operation, rapid in response and cost-effective. In view of the advantages, the developed system demonstrates great potential for the detection of TCs in environmental and biological samples.


Assuntos
Európio/química , Grafite/química , Limite de Detecção , Pontos Quânticos/química , Tetraciclinas/análise , Animais , Medições Luminescentes , Leite/química , Modelos Moleculares , Conformação Molecular , Rios/química , Tetraciclinas/química
7.
J Mater Chem B ; 6(42): 6858-6864, 2018 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-32254702

RESUMO

Nanomaterial-based artificial enzymes (nanozymes), as an emerging generation of artificial enzymes, have received extensive attention in recent years owing to their striking merits. In this study, the obtained Co3O4 nanocrystals exhibited catalase-like activity and could catalyze the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) in the presence of H2O2, and a clear absorption peak at 652 nm can be observed. It was verified that the catalytic activity for the oxidation of TMB originated from the oxygen, which is generated by Co3O4 catalyzed H2O2 decomposition. Upon addition of glutathione (GSH), the catalytic ability of the Co3O4 nanocrystals was inhibited. And, the changes of absorbance at 652 nm could be utilized to quantify the concentration of GSH. Under the optimized conditions, the proposed assay showed good linear relationships and a low detection limit towards GSH. Moreover, the Co3O4 nanocrystals had excellent stability and can maintain the catalytic activity for a long time. Thus, a simple, sensitive and selective nanozyme-based biosensor was developed for the colorimetric detection of GSH.

8.
Zhonghua Wei Chang Wai Ke Za Zhi ; 19(8): 928-32, 2016 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-27545470

RESUMO

OBJECTIVE: To study postoperative anorectal dynamic change in ultra-low rectal cancer patients undergoing laparoscopic intersphincteric resection. METHODS: Clinical and follow-up data of 26 ultra-low rectal cancer patients undergoing laparoscopic intersphincteric resection in our department from January 2007 to January 2013 were retrospectively analyzed (observation group). Thirty rectal cancer patients undergoing laparoscopic low anterior resection by the same surgical team in the same period from the Medical Record Room were randomly extracted as control group. The observation indexes included preoperative and postoperative anal resting pressure(ARP), anal maximum squeeze pressure (AMSP), rectal maximum tolerable volume (RMTV), rectal anal inhibition reflex (RAIR) and Wexner anal function scores (0 means normal). RESULTS: There were no significant differences in clinical baseline data between the two groups(all P>0.05), except the distance from lower edge of tumor to dentate line [(2.9±0.4) cm in observation group vs. (5.0±0.5) cm in control group, P=0.000]. There were no differences in preoperative anorectal manometry and Wexner anal function score between two groups (all P>0.05). The average follow-up time in observation group and control group was 14.5 months and 14.0 months respectively. Three months after operation, significant differences between observation group and control group (all P=0.000) were as follows: defecation frequency [(6.0±1.5) times/day vs. (2.5±1.0) times/day], Wexner anal function score(5.0±0.9 vs. 2.9±1.2), ARP [(32.0±6.7) mmHg vs. (45.0±8.2) mmHg], AMSP [(90.1±6.9) mmHg vs. (110.0±7.5) mmHg], RMTV [(61.0±7.2) ml vs. (91.1±7.5) ml] and positive rate of RAIR [11.5%(3/26) vs. 66.7%(20/30)]. One year after surgery, there were no significant differences in defecation frequency, Wexner anal function scores, ARP, AMSP and RMTV between the two groups (all P>0.05), however the difference in positive rate of RAIR was still significant[38.5%(10/26) vs. 93.3%(28/30), P=0.000]. CONCLUSION: Laparoscopic intersphincteric resection for ultra- low rectal cancer can achieve satisfactory anorectal dynamic effect.


Assuntos
Canal Anal/fisiopatologia , Laparoscopia , Neoplasias Retais/cirurgia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Pressão , Reto/fisiopatologia , Estudos Retrospectivos
9.
Nanotechnology ; 27(34): 345703, 2016 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-27418592

RESUMO

Upconversion nanoparticles (UCNPs) hold promise as near-infrared light converters to enhance the efficiency of solar cells. However, the prevalent use of UCNPs in solar cells is restricted by their poor electrical conductivity and low emission efficiency. Here reduced graphene oxide (rGO)-NaYF4:Yb(3+)/Er(3+) composites are proposed to achieve good electrical conductivity due to the high charge carrier mobility of rGO. Composites of rGO and UCNPs combined by a chemical bond are in situ synthesized by the hydrothermal method, followed by a reduction process. The contact of UCNPs with rGO is proved by SEM, and the binding between the rGO-UCNP composites is confirmed by Fourier transform infrared spectroscopy. The composites are doped into the photoanode of a solar cell. As anticipated, electrochemical impedance spectroscopy confirms the good electrical conductivity of the in situ synthesized rGO-UCNPs. Furthermore, the use of rGO-UCNPs in solar cells enables an enhancement in short-circuit current density and overall efficiency by about 10%. These findings reveal that the combination of UCNPs with rGO opens up new opportunities of extending the use of UCNPs in the area of solar energy harvesting.

10.
Surg Endosc ; 30(7): 2759-65, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26487219

RESUMO

BACKGROUND: Slow-transit constipation complicated with rectocele is a mixed constipation difficult to treat by surgery. Different hospitals and surgeons may employ different surgical procedures. The present study aims to compare the efficacy of laparoscopic subtotal colectomy (LSC) with posterior vaginal suspension and LSC with transvaginal repair for patients having refractory slow-transit constipation complicated with rectocele. METHODS: This paper is a retrospective study of 64 patients having refractory slow-transit constipation complicated with rectocele. Admitted from January 2002 to December 2012, the 64 patients were non-randomly divided into two groups: patients who underwent LSC with posterior vaginal suspension (Group A, 36 patients) and patients who underwent LSC with transvaginal repair (Group B, 28 patients). RESULTS: There was no statistically significant difference (P > 0.05) in preoperative general characteristics and Wexner constipation score between Group A and Group B. There was no statistically significant difference (P > 0.05) in operative time and intraoperative blood loss between the two groups. One month after the surgery, there was no statistically significant difference (P > 0.05) in early postoperative complications, constipation recurrence rate, degree of improvement in constipation symptoms, and Wexner constipation score between the two groups. But 1-year follow-up results show that there was statistically significant difference (P < 0.05) in constipation recurrence rate, gastrointestinal quality of life index, the degree of improvement in constipation symptoms, and Wexner constipation score between the two groups. CONCLUSION: Compared with the LSC with transvaginal repair, the LSC with posterior vaginal suspension demonstrated better efficacy in treating refractory slow-transit constipation complicated with rectocele.


Assuntos
Colectomia/métodos , Constipação Intestinal/cirurgia , Complicações Pós-Operatórias/epidemiologia , Procedimentos Cirúrgicos Reconstrutivos/métodos , Retocele/cirurgia , Vagina/cirurgia , Idoso , Perda Sanguínea Cirúrgica , Constipação Intestinal/complicações , Feminino , Humanos , Laparoscopia/métodos , Pessoa de Meia-Idade , Duração da Cirurgia , Qualidade de Vida , Retocele/complicações , Estudos Retrospectivos , Resultado do Tratamento
11.
J Integr Plant Biol ; 57(5): 468-76, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25040477

RESUMO

Since pepc gene encoding phosphoenolpyruvate carboxylase (PEPCase) has been cloned from Anabaena sp. PCC 7120 and other cyanobacteria, the effects of pepc gene expression on photosynthesis have not been reported yet. In this study, we constructed mutants containing either upregulated (forward) or downregulated (reverse) pepc gene in Anabaena sp. PCC 7120. Results from real-time quantitative polymerase chain reaction (RT-qPCR), Western blot and enzymatic analysis showed that PEPCase activity was significantly reduced in the reverse mutant compared with the wild type, and that of the forward mutant was obviously increased. Interestingly, the net photosynthesis in both the reverse mutant and the forward mutant were higher than that of the wild type, but dark respiration was decreased only in the reverse mutant. The absorbance changes of P700 upon saturation pulse showed the photosystem I (PSI) activity was inhibited, as reflected by Y(I), and Y(NA) was elevated, and dark reduction of P700(+) was stimulated, indicating enhanced cyclic electron flow (CEF) around PSI in the reverse mutant. Additionally, the reverse mutant photosynthesis was higher than that of the wild type in low temperature, low and high pH, and high salinity, and this implies increased tolerance in the reverse mutant through downregulated pepc gene.


Assuntos
Adaptação Fisiológica/genética , Anabaena/genética , Meio Ambiente , Regulação Bacteriana da Expressão Gênica , Genes Bacterianos , Complexo de Proteína do Fotossistema I/metabolismo , Estresse Fisiológico/genética , Respiração Celular , Escuridão , Regulação para Baixo/genética , Transporte de Elétrons , Vetores Genéticos , Concentração de Íons de Hidrogênio , Mutação/genética , Fotossíntese , Complexo de Proteína do Fotossistema II/metabolismo , Teoria Quântica , Salinidade , Temperatura , Regulação para Cima/genética
12.
Zhonghua Yi Xue Za Zhi ; 92(36): 2553-5, 2012 Sep 25.
Artigo em Chinês | MEDLINE | ID: mdl-23158797

RESUMO

OBJECTIVE: To explore the causes of postoperative anastomotic leakage of colorectal cancer. METHODS: A total of 1462 cases with colorectal cancer undergoing laparoscopic operation and intestinal anastomosis at our department over the last decade were analyzed retrospectively. Data analysis was performed with SPSS 13.0. The risk factors were analyzed by binary Logistic regression while the annual incidence of anastomotic leakage by trend χ(2) test. RESULTS: Thirty anastomotic leakage occurred in 1462 cases with an incidence rate of 2.1%. There were significant correlations of anastomotic leakage with body built, tumor location, tumor size, operation time (χ(2) = 6.117, 50.167, 36.693, 4.481, P = 0.013, 0.000, 0.000, 0.034). However, there was no correction with gender, age or histological type (P = 0.871, 0.775, 1.000). Then the significance check of binary Logistic regression equation was performed. Tumor location was an independent risk factor of postoperative anastomotic leakage for colorectal cancer. The relative risk was 2.056. The annual incidence of anastomotic leakage was statistically insignificant (χ(2) = 1.827, P = 0.176). And the difference was. CONCLUSIONS: The occurrence of anastomotic leakage after colorectal cancer surgery is significantly correlated with body built, tumor location, tumor size and operation time. And tumor location below peritoneal reversal is an independent risk factor of anastomotic leakage.


Assuntos
Anastomose Cirúrgica/efeitos adversos , Fístula Anastomótica/etiologia , Laparoscopia/efeitos adversos , Complicações Pós-Operatórias/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/cirurgia , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
13.
Yi Chuan Xue Bao ; 33(2): 171-80, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16529301

RESUMO

The joint segregation analysis of a mixed genetic model of major gene plus poly-gene was conducted to study the inheritance of oil content in Brassica napus L.. Five populations, i.e the populations of 2 parents (P1 and P2), F1, F2 and F2:3 (derived from F2) family, from each of the two crosses (1141B x Ken C-1, 32B x Ken C1-2) were investigated.The frequency distributions of oil content in F2 and F2:3 family populations show characteristics of a mixed normal distribution, which indicated that the inheritance of oil content followed a major gene plus poly-gene model. Twenty-one genetic models were established, which could be classified into five types: one and two major genes, polygenes, one and two major genes plus polygenes. The most suitable genetic model could be selected using Akaike's Information Criterion and the fitness of the selected one could be examined by a set of tests. Results show that genetic model D-2 is the most fitting genetic model for the trait. In other words, oil content in oilseed rape is controlled by one additive major gene plus additive and dominance polygenes. For cross 1 (1141B x Ken C1-1) the heritabilities of major gene and poly-genes in F2 are 68.21% and 27.17%, respectively, and in F2:3 are 81.70% and 16.80%, respectively. The additive effect of major gene is -1.74, which indicates that the locus of the allele in parent 1141B may decrease the oil content, but that in parent Ken C1-1 may increase it. The additive and dominance effects of the polygenes are 1.20 and -1.93, respectively. For cross 2 (32B x Ken C1-2) the heritabilities of major gene and polygenes in F2 are 66.20% and 28.10%, respectively, and in F2:3 were 81.00% and 14.90%, respectively. The additive effect of major gene was -3.74, which also indicates that the locus of the allele in parent 32B may decrease the oil content, but that in parent Ken C1-2 may increase it. The additive and dominance effects are -1.99 and 0.93, respectively. The heritability of the major gene in F2:3 is higher than that in F2 in both crosses, so it would be more efficent to conduct selection in F2:3 families for high oil content in breeding.


Assuntos
Brassica napus/genética , Brassica napus/metabolismo , Genes de Plantas/genética , Óleos Vegetais/metabolismo , Cruzamentos Genéticos , Genes Dominantes , Modelos Genéticos , Herança Multifatorial/genética
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