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1.
Artigo em Inglês | MEDLINE | ID: mdl-38758376

RESUMO

PURPOSE: To compare the accuracy of 14 formulas in calculating intraocular lens (IOL) power in extremely long eyes with axial length (AL) over 30.0 mm. METHODS: In this retrospective study, 211 eyes (211 patients) with ALs > 30.0 mm were successfully treated with cataract surgery without complications. Ocular biometric parameters were obtained from IOLMaster 700. Fourteen formulas were evaluated using the optimized A constants: Barrett Universal II (BUII), Kane, Emmetropia Verifying Optical (EVO) 2.0, PEARL-DGS, T2, SRK/T, Holladay 1, Holladay 2, Haigis and Wang-Koch AL adjusted formulas (SRK/Tmodified-W/K, Holladay 1modified-W/K, Holladay 1NP-modified-W/K, Holladay 2modified-W/K, Holladay 2NP-modified-W/K). The mean prediction error (PE) and standard deviation (SD), mean absolute errors (MAE), median absolute errors (MedAE), and the percentage of prediction errors (PEs) within ± 0.25 D, ± 0.50 D, ± 1.00 D were analyzed. RESULTS: The Kane formula had the smallest MAE (0.43 D) and MedAE (0.34 D). The highest percentage of PE within ± 0.25 D was for EVO 2.0 (37.91%) and the Holladay 1NP-modified-W/K formulas (37.91%). The Kane formula had the highest percentage of PEs in the range of ± 0.50, ± 0.75, ± 1.00, and ± 2.00 D. There was no significant difference in PEs within ± 0.25, ± 0.50 ± 0.75 and ± 1.00 D between BUII, Kane, EVO 2.0 and Wang-Koch AL adjusted formulas (P > .05) by using Cochran's Q test. The Holladay 2modified-W/K formula has the lowest percentage of hyperopic outcomes (29.38%). CONCLUSIONS: The BUII, Kane, EVO 2.0 and Wang-Koch AL adjusted formulas have comparable accuracy for IOL power calculation in eyes with ALs > 30.0 mm.

2.
Environ Res ; 238(Pt 2): 117247, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37769833

RESUMO

Freshwater lakes undergo substantial alterations of the phosphorus (P) cycle in the water-sediment ecosystem due to thermal change. The impact process of seasonal fluctuation on P cycling in sediments has been scarcely investigated. P forms in sediments from a freshwater lake in China were analyzed using sequential extraction technique. The vertical distribution of soluble reactive P (SRP), Fe2+, and S2- in the interstitial water was measured using diffusion gradient technique (DGT). Fick's Law and DIFS model were used to obtain the diffusion fluxes of SRP and the kinetic parameters in the water-sediment system. The results showed that total P (TP) concentrations in the solid sediments varied from 207.5, 266.6 and 130.3 mg/kg to 614.7, 1053.1, and 687.6 mg/kg in winter, spring, and summer, respectively. The concentrations of individual P forms in spring were higher than those in other seasons, with Fe-bound P (Fe-P) concentration being the highest across all seasons. Notably, significant variations of SRP concentrations were found in the interstitial water between sedimentary depths of approximately 2 cm and 6 cm, particularly in the summer. Furthermore, higher diffusion fluxes of SRP through the interface were found in summer. A stable anaerobic environment failed to develop in spring with high water level, preventing the desorption of solid Fe-P and diffusion of Fe2+ into the water due to the afflux and deposition of P-containing particulate into deeper sediment layers along with organic material. Under extreme high-temperature in summer, decreased rainfall and rising temperatures boosted the activity of aquatic organisms in the water, thereby reducing P fixation by sediments and leading to P release. This process increased the risk of P excess and potential eutrophication in the water. Generally, clarifying the resupplying processes of endogenous P in sediment systems experiencing seasonal variations is critical for eutrophication management of lakes.


Assuntos
Lagos , Poluentes Químicos da Água , Estações do Ano , Água , Fósforo/análise , Ecossistema , Poluentes Químicos da Água/análise , Sedimentos Geológicos , Monitoramento Ambiental/métodos , Eutrofização , China
3.
Med Sci Monit ; 25: 10205-10211, 2019 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-31891939

RESUMO

BACKGROUND The aim of this study was to compare the intra-operative parameters and post-operative outcomes of cataract surgery performed using the cystotome-assisted prechop (CAP) and phaco-chop techniques. MATERIAL AND METHODS Fifty-two eyes with age-related cataract in the CAP group, and 63 eyes in the phaco-chop group were enrolled for analysis in this study, and the surgical outcomes were reported 1 day and/or 1 week, and 1 month post-operatively. RESULTS The CAP technique was associated with statistically significantly lower cumulative dissipated energy compared with the phaco-chop technique (P<0.001). The mean endothelial cell loss in the CAP group was statistically significantly lower than that of the phaco-chop group 1 week (5.6±5.9% versus 8.8±8.7%, P=0.020) and 1 month post-operatively (6.3±6.8% versus 9.8±9.9%, P=0.026). The change in the central corneal thickness between the 2 groups was significantly different at 1 day post-operatively (3.3±3.1% versus 4.9±4.6%, P=0.036). The change in the 8.0 mm central corneal volume between the 2 groups was significantly different at 1 day and 1 week post-operatively (6.5±6.1% versus 10.9±7.9%, P=0.001; 3.2±4.7% versus 5.4±5.7%, P=0.029, respectively). CONCLUSIONS The CAP technique showed lower ultrasound energy consumption and less endothelial damage and corneal edema than the phaco-chop technique. It might therefore prove a cost-effective prechop method for cataract surgery.


Assuntos
Facoemulsificação/instrumentação , Facoemulsificação/métodos , Idoso , Idoso de 80 Anos ou mais , Catarata/patologia , Córnea/patologia , Córnea/cirurgia , Paquimetria Corneana , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cuidados Pós-Operatórios , Cuidados Pré-Operatórios
4.
J Nanosci Nanotechnol ; 19(8): 5264-5270, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-30913843

RESUMO

Cetyltrimethyl ammonium bromide (CTAB) template was used in a sol-gel route to synthesize porous cerium titanate. The fractions of CeTi2O6, CeO2, anatase TiO2 and rutile TiO2 phases in the materials vary with calcination temperature ranging from 600 to 1000 °C. FT-Far IR spectra prove the far infrared absorption of Ce-O and Ti-O bonds in the materials. The band gap energies of the crystallized materials are around 3.0 eV and are not noticeably affected by calcination temperature. The BET surface area constantly shrinks from 65.4 m²/g at 600 °C to 2.1 m²/g at 1000 °C. Meanwhile, the total pore volume decreases from 0.2057 cm³/g at 600 °C to 0.0024 cm³/g at 1000 °C. The adsorption capacity of the materials drastically decreases with increasing calcination temperature, which is in close relationship to the change of BET surface area. The porous cerium titanate sample obtained at 800 °C has the maximum photocatalytic activity on both ofloxacin degradation and hydroxyl radical productivity. When calcination temperature increases from 600 °C to 800 °C, photocatalytic degradation efficiency is enhanced from 31.2% to 56.7%.


Assuntos
Cério , Ofloxacino , Catálise , Porosidade , Titânio
5.
BMC Ophthalmol ; 19(1): 77, 2019 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-30871533

RESUMO

BACKGROUND: This study aimed to investigate the completion rate, visual performance, and adverse outcomes of femtosecond laser-assisted cataract surgery (FLACS) in Chinese patients. METHODS: This is a prospective, single-arm, multicenter registry study of 19 cataract surgery clinics in China. Chinese patients with cataract who underwent FLACS using the Alcon LenSx® laser system in single eye (n = 1140) or both eyes (n = 201) were enrolled and data were collected between March 2015 and August 2016. Clinical characteristics were recorded before surgery, and on postoperative days 1, 7, and 30. For surgery on both eyes, the second eye was included in the analysis only if it was operated within 30 days after the first eye surgery. The primary outcome was the completion rate of circular anterior capsulotomy. Secondary outcomes for lens fragmentation, corneal incision, and intraocular lens (IOL) implantation included best corrected distance visual acuity (BCDVA) and completion rates. Adverse events (AEs) were recorded. RESULTS: The completion rates of circular anterior capsulotomy, lens fragmentation, corneal incision, and IOL implantation were 98.6% (95% CI: 97.8-99.1%), 99.5% (95% CI: 99.1-99.8%), 97.6% (95% CI: 96.7-98.3%), and 100% (95% CI: 99.8-100%), respectively. BCDVA preoperatively and at postoperative day 30 were 1.134 ± 0.831 logMAR and 0.158 ± 0.291 logMAR, respectively. The proportion of eyes with BCDVA of 20/20 or better was 1.6% at baseline and 41.3% at postoperative day 30. AE incidence was 0.32%, with posterior capsule rupture present in 0.19% of eyes. CONCLUSION: FLACS using the LenSx® laser system can achieve satisfactory results in a real-world setting.


Assuntos
Extração de Catarata/métodos , Terapia a Laser/métodos , Adulto , Idoso , Capsulorrexe/estatística & dados numéricos , China , Feminino , Humanos , Complicações Intraoperatórias , Implante de Lente Intraocular , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Prospectivos , Acuidade Visual
6.
Arch Biochem Biophys ; 564: 52-66, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-25201588

RESUMO

Nicotinamide N-methyltransferase (NNMT), an enzyme involved in the biotransformation and detoxification of many drugs and xenobiotic compounds, has been found to be overexpressed in several malignancies, including colorectal cancer. However, the biological function of NNMT and the related mechanisms in colorectal cancer have not been elucidated. In the present study, we investigated the effects of NNMT on tumorigenesis by overexpressing NNMT in the human colorectal cancer cells line SW480 which lacks constitutive NNMT expression, and downregulating NNMT expression in HT-29 cells, which exhibit high endogenous expression of NNMT. We found that NNMT significantly accelerates cell proliferation, enhances colony formation in vitro and tumorigenicity in mice; it also inhibits apoptosis, promotes cell cycle progression, increases ATP and 1-methylnicotinamide level and decreases ROS level. We also showed that 1-methylnicotinamide accelerates cell growth, inhibits apoptosis, promotes cell cycle progression, attenuates ROS production and increases ATP level. Our results indicate that NNMT enhances the capacity of tumorigenesis associated with the inhibition of cell apoptosis and the promotion of cell cycle progression in human colorectal cancer cells and the 1-methylnicotinamide increased by NNMT mediates the cellular effects of NNMT in cells. NNMT may play a vital role in energy balance and ROS induction.


Assuntos
Ciclo Celular , Neoplasias Colorretais/enzimologia , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Proteínas de Neoplasias/biossíntese , Nicotinamida N-Metiltransferase/biossíntese , Trifosfato de Adenosina/genética , Trifosfato de Adenosina/metabolismo , Animais , Apoptose/genética , Linhagem Celular Tumoral , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Metabolismo Energético/genética , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas de Neoplasias/genética , Nicotinamida N-Metiltransferase/genética , Espécies Reativas de Oxigênio/metabolismo
7.
Proteome Sci ; 12(1): 53, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25425973

RESUMO

BACKGROUND: Transcription factors bind to response elements on the promoter regions of genes to regulate transcriptional activity. One of the major problems with identifying transcription factors is their low abundance relative to other proteins in the cell. Developing a purification technique specific for transcription factors is crucial to the understanding of gene regulation. Promoter trapping is a method developed that uses the promoter regions as bait to trap proteins of interest and then purified using column chromatography. Here we utilize this technique to study the telomerase promoter, which has increased transcriptional activity in cancer cells. Gaining insight on how to control the enzyme at the promoter level may give new routes towards cancer treatments. RESULTS: Our findings show that the telomerase promoter (-170 - +91) and Promoter Trapping isolate a transcriptionally active and reproducible complex, when analyzed by liquid chromatography tandem mass spectrometry. We were also able to identify transcription factors, including AP-2 and SP1 known to bind this promoter, as well as show that these two proteins can bind to each other's response element. CONCLUSION: Here we focus on verifying the ability and versatility of Promoter Trapping coupled with additional well-characterized methods to identify already known factors responsible for telomerase transcriptional regulation.

8.
Discov Nano ; 19(1): 125, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39115796

RESUMO

Blood vessels are highly dynamic and complex structures with a variety of physiological functions, including the transport of oxygen, nutrients, and metabolic wastes. Their normal functioning involves the close and coordinated cooperation of a variety of cells. However, adverse internal and external environmental factors can lead to vascular damage and the induction of various vascular diseases, including atherosclerosis and thrombosis. This can have serious consequences for patients, and there is an urgent need for innovative techniques to repair damaged blood vessels. Polyesters have been extensively researched and used in the treatment of vascular disease and repair of blood vessels due to their excellent mechanical properties, adjustable biodegradation time, and excellent biocompatibility. Given the high complexity of vascular tissues, it is still challenging to optimize the utilization of polyesters for repairing damaged blood vessels. Nevertheless, they have considerable potential for vascular tissue engineering in a range of applications. This summary reviews the physicochemical properties of polyhydroxyalkanoate (PHA), polycaprolactone (PCL), poly-lactic acid (PLA), and poly(lactide-co-glycolide) (PLGA), focusing on their unique applications in vascular tissue engineering. Polyesters can be prepared not only as 3D scaffolds to repair damage as an alternative to vascular grafts, but also in various forms such as microspheres, fibrous membranes, and nanoparticles to deliver drugs or bioactive ingredients to damaged vessels. Finally, it is anticipated that further developments in polyesters will occur in the near future, with the potential to facilitate the wider application of these materials in vascular tissue engineering.

9.
J Neurooncol ; 115(2): 233-9, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23959833

RESUMO

The causes of meningiomas are not well understood. Folate metabolism gene polymorphisms have been shown to be associated with various human cancers. It is still controversial and ambiguous between the functional polymorphisms of folate metabolism genes 5,10-methylenetetrahydrofolate reductase (MTHFR), methionine synthase (MTRR), and methionine synthase reductase (MTR) and risk of adult meningioma. A population-based case­control study involving 600 meningioma patients (World Health Organization [WHO] Grade I, 391 cases; WHO Grade II, 167 cases; WHO Grade III, 42 cases) and 600 controls was done for the MTHFR C677T and A1298C, MTRR A66G, and MTR A2756G variants in Chinese Han population. The folate metabolism gene polymorphisms were determined by using a polymerase chain reaction­restriction fragment length polymorphism assay. Meningioma cases had a significantly lower frequency of MTHFR 677 TT genotype [odds ratio (OR) = 0.49, 95 % confidence interval (CI) 0.33­0.74; P = 0.001] and T allele (OR = 0.80, 95 % CI 0.67­0.95; P = 0.01) than controls. A significant association between risk of meningioma and MTRR 66 GG (OR = 1.41, 95 % CI 1.02­1.96; P = 0.04) was also observed. When stratifying by the WHO grade of meningioma, no association was found. Our study suggested that MTHFR C677T and MTRR A66G variants may affect the risk of adult meningioma in Chinese Han population.


Assuntos
5-Metiltetra-Hidrofolato-Homocisteína S-Metiltransferase/genética , Ferredoxina-NADP Redutase/genética , Neoplasias Meníngeas/genética , Meningioma/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Polimorfismo de Nucleotídeo Único/genética , Adulto , Estudos de Casos e Controles , China/epidemiologia , Feminino , Seguimentos , Genótipo , Humanos , Masculino , Neoplasias Meníngeas/epidemiologia , Neoplasias Meníngeas/patologia , Meningioma/epidemiologia , Meningioma/patologia , Pessoa de Meia-Idade , Gradação de Tumores , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Prognóstico , Fatores de Risco
10.
Clin Lab ; 59(7-8): 813-7, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24133910

RESUMO

BACKGROUND: CA 19-9 is one of the most frequently used biomarkers for tumors. METHODS: We analyzed the influential factors of the Carbohydrate Antigen 19-9 (CA 19-9) levels in Chinese general population to better interpret the results of the CA 19-9 screening tests. 36,924 apparently healthy individuals and 1,335 patients with gastrointestinal (GI) tumors were involved in this study. Serum CA 19-9 levels were measured using a Roche Cobas E601. RESULTS: The serum CA 19-9 levels in apparently healthy individuals were correlated with age and gender. Its level was positively correlated with the age of males, while it showed a V-shape curve in female populations. This effect could be due to sex hormones, such as prolactin, which were found to have a negative effect on the level of CA 19-9 in the present study. CONCLUSIONS: Our data indicates that gender and age could affect the CA19-9 serum level. We can set up different cut-off values according to the patient's gender and age, which can help us to get a more individualized representation in different populations.


Assuntos
Biomarcadores Tumorais/sangue , Antígeno CA-19-9/sangue , Adolescente , Adulto , Idoso , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
11.
Indian J Ophthalmol ; 71(2): 541-546, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36727357

RESUMO

Purpose: To evaluate a method using measured values of total corneal refractive power (TCRP) for a manufacturer's online calculator by comparing it with the Barrett toric calculator (BTC) and Kane toric calculator (KTC) combined with simulated keratometry values (SimK). Methods: This was a retrospective case series. Patient records were reviewed to identify the patients who had biometry with the IOL Master 700 and Pentacam recorded before toric IOL implantation and refractive follow-up data after implantation. The predicted error in residual astigmatism was calculated by vector analysis according to the calculation methods and the measurements used. Results: A total of 70 eyes of 56 patients were included. The mean absolute astigmatism prediction errors were 0.6 ± 0.32, 0.59 ± 0.35, and 0.61 ± 0.35 D for the ATCTCRP, BTCSimK, and KTCSimK calculators, respectively (P = 0.934), and the centroid of the prediction errors were 0.3 D @ 178°, 0.11 D @ 102°, and 0.09 D @ 147°, respectively (P = 0.23). In the with-the-rule subgroup, the centroid of the prediction error was 0.34 D @ 176° for ATCTCRP and was the highest among the three calculation methods (P = 0.046). Conclusion: The ATCTCRP, BTCSimK, and KTCSimK calculators had similar performance with regards to their astigmatism prediction accuracy. The ATCTCRP calculator combined with 4.0-mm apex/ring readings of TCRP was slightly intended to result in against-the-rule residual astigmatism.


Assuntos
Astigmatismo , Lentes Intraoculares , Facoemulsificação , Humanos , Implante de Lente Intraocular/métodos , Astigmatismo/diagnóstico , Astigmatismo/cirurgia , Acuidade Visual , Estudos Retrospectivos , Topografia da Córnea , Córnea , Refração Ocular
12.
Indian J Ophthalmol ; 71(8): 2967-2971, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37530266

RESUMO

Purpose: To evaluate whether the toric intra-ocular lens (IOL) power calculation based on total corneal astigmatism (TCA) in eyes with high posterior corneal astigmatism (PCA) could result in a systematic over-correction or under-correction after operation. Methods: The present study included a mono-centric retrospective study design. The data were collected from 62 consecutive eyes during uncomplicated cataract surgery by a single surgeon with a measured PCA of 0.50 diopters (D) or higher. Toric IOL calculations were made using TCA measurements. The eyes were grouped as either "with-the-rule" (WTR) or "against-the-rule" (ATR) on the basis of the steep anterior corneal meridian. The post-operative refractive astigmatic prediction error was analyzed 1 month post-operatively using the vector analysis by the Alpins method and double-angle plots method. Results: The correction indexes were 1.14 ± 0.29 in the ATR eyes and 1.25 ± 0.18 for the WTR eyes, indicating a tendency toward over-correction. The mean over-correction was 0.22 ± 0.52D in the ATR group and 0.65 ± 0.60D in the WTR group. The magnitude of error (ME) values were significantly different from the ideal value of zero in both groups (ATR: P = 0.03; WTR: P = 0.00). No significant difference in mean absolute error (MAE) in predicted residual astigmatism was found between ATR and WTR groups (0.61 ± 0.42 D versus 0.64 ± 0.39 D; P = 0.54). The ATR group yielded better results, with 48% <0.50D prediction error in the main analysis. Conclusions: The results suggested that in cases of high PCA, the toric IOL calculation, which was performed using TCA, may cause a potential over-correction in the ATR and WTR eyes. For ATR eyes, over-correction led to slight disruption of post-operative visual quality because of the "with-the-rule" residual astigmatism after operation. Therefore, we suggested using TCA for toric IOL calculation in ATR eyes.


Assuntos
Astigmatismo , Doenças da Córnea , Lentes Intraoculares , Facoemulsificação , Humanos , Astigmatismo/diagnóstico , Astigmatismo/cirurgia , Implante de Lente Intraocular , Estudos Retrospectivos , Topografia da Córnea , Facoemulsificação/métodos , Refração Ocular , Doenças da Córnea/cirurgia
13.
Biomater Sci ; 11(5): 1828-1839, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36655811

RESUMO

Bactericidal nanomedicines often suffer from a complicated design and insufficient intrinsic inhibitory efficacy. Herein, novel anti-bacterial copper telluride (CuTe) nano-clusters are reported, featuring superior bactericidal efficiency, facile preparation, and unique mechanism. These nanoparticles, well dispersable in water, resembled grape clusters with rough surfaces. The CuTe nano-grape clusters exhibited ultra-high sterilization efficacy at ultra-low concentration, particularly for Gram-negative bacteria, and were more potent than conventional anti-microbial nanoparticles. Also, the grape clusters effectively inhibited the bacterial biofilm development. Further investigation revealed the synergized mechanisms of reactive oxygen species (ROS) generation and glutathione (GSH) depletion. Interestingly, electron microscopy revealed that the grape clusters served as bacterial hunters by tightly adhering to bacterial surfaces. The bacteria subsequently suffered from the leakage of various intracellular components including nucleic acid, proteins, and potassium. Most encouragingly, CuTe drastically reduced bacterial number in a mouse model with lethal intraperitoneal infection and increased the mouse survival rate to 90%. This finding could inspire the development of highly potent bactericidal inorganic formulations with simplified structure, multiple antibacterial mechanisms, and promising application potential.


Assuntos
Cobre , Nanopartículas , Camundongos , Animais , Cobre/química , Antibacterianos/química , Nanopartículas/química , Espécies Reativas de Oxigênio/metabolismo , Bactérias Gram-Negativas , Glutationa/metabolismo , Testes de Sensibilidade Microbiana
14.
Anal Biochem ; 427(2): 133-8, 2012 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-22633908

RESUMO

Synthesis of (GT)5-tailed duplex DNA promoter is an important first step for purifying transcription complexes by promoter trapping purification. In our previous publication, we showed that the purification of the c-jun promoter using lambda exonuclease digestion of polymerase chain reaction (PCR) produced DNA with single-stranded tails. Asymmetric PCR can also produce tailed single strands that can be annealed to yield the desired promoter. An effective method uses asymmetric PCR and double digestion. After PCR, first a restriction enzyme, in this case SacII, cuts duplex strands remaining after asymmetric PCR, leaving 5' phosphoryl ends susceptible to a second digestion with lambda exonuclease to effectively degrade any duplex. The resulting single strands are then annealed to produce a duplex DNA with a single-stranded (GT)5 tail at the 3' end of each strand of the duplex. Unlike the previously described method, this novel procedure produces the desired tailed promoter devoid of any untailed duplex.


Assuntos
Cromatografia de Afinidade/métodos , DNA/análise , Reação em Cadeia da Polimerase/métodos , Regiões Promotoras Genéticas , Transcrição Gênica , Southwestern Blotting , DNA/genética , Enzimas de Restrição do DNA/genética , Enzimas de Restrição do DNA/metabolismo , DNA de Cadeia Simples/análise , DNA de Cadeia Simples/genética , Eletroforese em Gel Bidimensional , Exonucleases/genética , Exonucleases/metabolismo , Genes jun/genética , Humanos , Vírus da Leucemia Murina de Moloney/química , DNA Polimerase Dirigida por RNA/genética , DNA Polimerase Dirigida por RNA/metabolismo
15.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 41(3): 281-8, 2012 05.
Artigo em Zh | MEDLINE | ID: mdl-22723163

RESUMO

OBJECTIVE: To investigate the effects of silencing the expression of mutant p53 gene with RNA interference technique on biological behavior of gastric cancer SGC7901 cells. METHODS: Recombinant plasmid of mutant p53 gene-targeting siRNA was transfected into gastric cancer SGC7901 cells by Lipofectamine(TM)2000. The expressions of mutant p53 gene mRNA and protein were identified by RT-PCR and Western blot assay. The proliferation of SGC7901 cells and changes of Oxaliplatin (OXA) drug sensitivity were detected by MTT assay. The cell cycle distribution and apoptosis rate were analyzed by flow cytometry. Changes in cell tumorigenicity ability were analyzed by colony formation assay and xenograft tumor formation in nude mice. RESULTS: The expression of mutant p53 in SGC7901 cells was remarkable suppressed by mutant p53-siRNA. The cell growth curve of the transfected group turned to left compared to untransfected group and control group. The cell number of G(0)/G(1) phase of transfected group was decreased by 7.4% and 6.7% respectively, and that of S phase was increased both by 17.2% compared to control group and untransfected group, and the cell apoptosis rate induced by Oxaliplatin was remarkable decreased. The IC(50) of OXA in untransfected group, control group and transfected group were 15.88 µmol/L, 14.32 µmol/L and 20.34 µmol/L respectively. The colony formation rate and tumorigenicity ability in nude mice of transfected group increased remarkably. CONCLUSION: Mutant p53-siRNA can significantly inhibit the expression of mutant p53 in SGC7901 cells, however, the use of RNA interference targeting mutant p53 gene in the treatment of gastric cancer is still uncertain.


Assuntos
Genes p53/genética , RNA Interferente Pequeno/genética , Neoplasias Gástricas/patologia , Animais , Apoptose/genética , Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Camundongos , Camundongos Nus , Plasmídeos/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Transfecção , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Sci Rep ; 12(1): 935, 2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-35042921

RESUMO

Tin-based perovskite material is the best choice to replace heavy metal element lead during the last several years. Cs2SnI6 with Sn4+ is a fascinating optoelectronic material, which is a more air-stable composite cesium tin halide peroxide variant from CsSnI3. However, the optoelectronic performance between N and P type of Cs2SnI6 varies considerably. Herein, we synthesized uniform Cs2SnI6 by modified two-step method, which thermal evaporated CsI firstly, and followed annealing in the SnI4 and I2 vapor at 150 °C resulted in uniform Cs2SnI6 films. SnF4 is used as a dopant source to improve the optoelectronic properties of Cs2SnI6 films. Results indicate that good crystallinity was obtained for all films and the doped films underwent a crystalline plane meritocracy transition. The doped films had a flat, non-porous morphology with large grains. The high transmittance of the doped films in the infrared region led to the avoidance of self-generated thermal decomposition. With the help of F-, the films became more conductive and had higher carrier mobility. DFT calculations showed that doping with F reduced the surface energy of (004), resulted in a preferred orientation transition in the crystal of Cs2SnI6. Fluorine doped double layer perovskite materials would have a broader application prospect.

17.
Chemosphere ; 305: 135382, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35718038

RESUMO

Phosphorus (P) is normally considered as the limited nutrient for shallow freshwater lakes and can potentially trigger eutrophication on account of high concentrations. Due to the various transportation and transformation processes, P source apportionment and management in lake ecosystems have become more and more difficult. Combining with sequential extraction of P fractions and mineralogical analysis, the isotopic compositions of oxygen in phosphate (δ18OP) of resin-extractable P from the different samples including soil, estuary sediments, pond sediments, and lake sediments in the Shijiuhu Lake catchment, China, were investigated. The results showed that δ18OP values ranged from +15.23 to +21.92‰ in agricultural soil, +16.53 to +24.10‰ in estuary sediments, +18.90 to +20.90‰ in pond sediments, and +17.42 to +19.70‰ in lake sediments. Isotopic signatures indicated that chemical fertilizers with heavier δ18OP values (+20.70 to +26.50‰) were the predominant contributors of P in the soil. The river transportation together with Fe/Al-P desorption on anaerobic condition simultaneously stimulated the enrichment of P in the lake sediments, even though the biotic activity regulated the isotope values moving toward the equilibrium. Eroded soil was the important source of P in lake and pond sediments via drainage and runoff, and conserved the source isotope signal in the samples. Stronger biotic activity in the aquatic environments dragged δ18OP values toward the equilibrium. However, conspicuous off-equilibrium isotope signature suggested the terrestrial sources in the aquatic ecosystems. The calculation of two end-member linear mixing models suggested that soils also predominantly controlled the P occurrence in the lake sediments with contribution higher than 80%, indicating that decreasing inputs from the agricultural activities is important in P reduction on catchment scale. Generally, δ18OP from different sources can provide indirect and important evidences for the identification and management of P sources in the lake catchment.


Assuntos
Lagos , Poluentes Químicos da Água , China , Ecossistema , Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Lagos/química , Isótopos de Oxigênio/análise , Fosfatos/análise , Fósforo/análise , Solo/química , Poluentes Químicos da Água/análise
18.
Int Immunopharmacol ; 110: 108987, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35820364

RESUMO

Progressive liver fibrosis is a dynamic process characterized by the net accumulation of extracellular matrix (ECM), which could eventually develop into cirrhosis, leading to malignant transformation. In this study, insulin-like growth factor 2 mRNA binding protein 2 (Igf2bp2) was found to be up-regulated in carbon tetrachloride (CCl4)-induced liver fibrosis and transforming growth factor-beta 1 (TGF-ß)-activated hepatic stellate cells (HSCs). Igf2bp2 knockdown in the CCl4-induced hepatic fibrosis mice model significantly improved CCl4-induced liver damage by decreasing necrosis and fibrotic septa, reducing hydroxyproline levels, and down-regulating fibrotic markers levels. In TGF-ß-activated HSCs, Igf2bp2 knockdown partially attenuated TGF-ß-induced cellular effects by suppressing HSCs viability and DNA synthesis and reducing the ECM-associated factors such as α-SMA, COLLAGEN I, and COLLAGEN III. Integrative network and signaling analysis revealed that the Igf2bp2 could bind to Tgfbr1. Transforming growth factor-beta receptor 1 (Tgfbr1) was found to be significantly up-regulated in the fibrotic liver and activated HSCs, and positively correlated with Igf2bp2. Tgfbr1 knockdown partially eliminated TGF-ß-induced fibrotic changes and Igf2bp2 overexpression effects on TGF-ß-activated HSCs in vitro. Moreover, Igf2bp2 overexpression promoted the phosphorylation of SMAD2/SMAD3, AKT, and PI3K, whereas Tgfbr1 knockdown exhibited the opposite effect; Tgfbr1 knockdown also partially attenuated the effects of Igf2bp2 overexpression on the phosphorylation of SMAD2/SMAD3, AKT, and PI3K. In closing, Igf2bp2 and Tgfbr1 are up-regulated in CCl4-induced liver fibrosis and TGF-ß-activated mHSCs. Igf2bp2 knockdown improved CCl4-induced liver fibrosis and TGF-ß-activated HSCs by targeting Tgfbr1, possibly through the PI3K/Akt pathway.


Assuntos
Células Estreladas do Fígado , Fosfatidilinositol 3-Quinases , Animais , Tetracloreto de Carbono/efeitos adversos , Colágeno Tipo I/metabolismo , Fígado/patologia , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/genética , Cirrose Hepática/metabolismo , Camundongos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Fatores de Crescimento Transformadores/efeitos adversos , Fatores de Crescimento Transformadores/metabolismo
19.
Chemosphere ; 303(Pt 1): 134664, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35460675

RESUMO

Nitrogen (N) and phosphorus (P) are crucial nutrients for eutrophication in the lacustrine ecosystem and attract the attention worldwide. However, the interaction between them need further clarification. This study aimed to assess the influence of dissimilatory nitrate reduction to ammonia (DNRA) on the cycle of P in lacustrine sediment. Different fractions of N and P in the pore water were measured using high-resolution in-situ measurement techniques, HR-Peeper and DGT, coupling with sequential extraction for solid sediment from a shallow freshwater lake. The results showed that elevated nitrate (NO3-) reduction via DNRA rather than denitrification was verified at deeper sediment layer, suggesting the generation of inorganic ammonia (NH4+) as electron donor under anaerobic episodes. High abundance of DNRA bacteria (nrfA gene) obtained using high-throughput sequencing analysis were detected at upper layer and responsible for the accumulation of NH4+ in the sediment coupling with chemolithoautotrophic metabolism. Additionally, significant desorption of ionic ferrous iron (Fe2+) and dissolved reactive phosphate (DRP) from solid phase and the enrichment in the solution was simultaneously detected. Higher concentration of solid Fe bound P (Fe-P) at deeper layer indicated the potential re-oxidation of Fe2+ as electron donor during DNRA process and sorption of DRP toward the Fe-containing minerals. However, obvious evidence of desorption proved by DGT indicated that higher NH4+ concentrations favored the reduction of Fe(III) oxy(hydr)oxides and the desorption of DRP into the pore water and diffusion toward the overlying water. Finally, noteworthy S2- release from solid sediment was speculated to stimulate the DNRA and facilitated the accumulation of NH4+ in the solution, which further induced the enrichment of DRP in water from the solid phase. Overall, DNRA potentially facilitates the accumulation of P in lake water, and the synchronous control of N and P is important for the eutrophication management and restoration of lake eutrophication.


Assuntos
Compostos de Amônio , Amônia , Compostos de Amônio/metabolismo , Desnitrificação , Ecossistema , Compostos Férricos , Sedimentos Geológicos , Lagos , Nitratos/análise , Nitrogênio , Óxidos de Nitrogênio , Compostos Orgânicos , Fósforo , Água/análise
20.
Materials (Basel) ; 14(10)2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-34064837

RESUMO

Research on the preparation and performance of graphene composite materials has become a hotspot due to the excellent electrical and mechanical properties of graphene. Among such composite materials, zinc oxide/graphene (ZnO/graphene) composite films are an active research topic. Therefore, in this study, we used the vacuum thermal evaporation technique at different evaporation voltages to fabricate an amorphous ZnO/graphene composite film on a flexible polyethylene terephthalate (PET). The amorphous ZnO/graphene composite film inherited the great transparency of the graphene within the visible spectrum. Moreover, its electrical properties were better than those of pure ZnO but less than those of graphene, which is not consistent with the original theoretical research (wherein the performance of the composite films was better than that of ZnO film and slightly lower than that of graphene). For example, the bulk free charge carrier concentrations of the composite films (0.13, 1.36, and 0.47 × 1018 cm-3 corresponding to composite films with thicknesses of 40, 75, and 160 nm) were remarkably lower than that of the bare graphene (964 × 1018 cm-3) and better than that of the ZnO (0.10 × 1018 cm-3). The underlying mechanism for the abnormal electrical performance was further demonstrated by X-ray photoelectron spectroscopy (XPS) detection and first-principles calculations. The analysis found that chemical bonds were formed between the oxide (O) of amorphous ZnO and the carbon (C) of graphene and that the transfer of the π electrons was restricted by C=O and C-O-C bonds. Given the above, this study further clarifies the mechanism affecting the photoelectric properties of amorphous composite films.

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