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1.
Chem Commun (Camb) ; 56(18): 2763-2766, 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32022002

RESUMO

A litchi-like MoSx-Fe@UiO-66-(OH)2 nanocomposite with amorphous MoSx-Fe nanoparticles uniformly anchored on the surface of UiO-66-(OH)2 is synthesized through sequential room-temperature redox and coordination reaction. The composite exhibits high catalytic activity and durability for hydrogen evolution in an acidic electrolyte, delivering 1000 mA cm-2 at -297 mV and outperforming Pt/C under high current densities.

2.
Adv Mater ; 32(3): e1806326, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30932263

RESUMO

Electrochemical water splitting is a promising technology for sustainable conversion, storage, and transport of hydrogen energy. Searching for earth-abundant hydrogen/oxygen evolution reaction (HER/OER) electrocatalysts with high activity and durability to replace noble-metal-based catalysts plays paramount importance in the scalable application of water electrolysis. A freestanding electrode architecture is highly attractive as compared to the conventional coated powdery form because of enhanced kinetics and stability. Herein, recent progress in developing transition-metal-based HER/OER electrocatalytic materials is reviewed with selected examples of chalcogenides, phosphides, carbides, nitrides, alloys, phosphates, oxides, hydroxides, and oxyhydroxides. Focusing on self-supported electrodes, the latest advances in their structural design, controllable synthesis, mechanistic understanding, and strategies for performance enhancement are presented. Remaining challenges and future perspectives for the further development of self-supported electrocatalysts are also discussed.

3.
Nanoscale ; 12(2): 967-972, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31840718

RESUMO

Nitrile hydratases (NHases) have attracted considerable attention owing to their application in the synthesis of valuable amides under mild conditions. However, the poor stability of NHases is still one of the main drawbacks for their industrial application. Recently, mesoporous metal-organic frameworks (MOFs) have been explored as an attractive support material for immobilizing enzymes. Here, we encapsulated a recombinant cobalt-type NHase from Aurantimonas manganoxydans into the cobalt-based MOF ZIF-67 by a biomimetic mineralization strategy. The nano-catalyst NHase1229@ZIF-67 shows high catalytic activity for the hydration of 3-cyanopyridine to nicotinamide, and its specific activity reached 29.5 U mg-1. The NHase1229@ZIF-67 nanoparticles show a significant improvement in the thermal stability of NHase1229. The optimum reaction temperature of NHase1229@ZIF-67 is at 50-55 °C, and it still retained 40% of the maximum activity at 70 °C. However, the free NHase1229 completely lost its catalytic activity at 70 °C. The half-lives of NHase1229@ZIF-67 at 30 and 40 °C were 102.0 h and 26.5 h, respectively. NHase1229@ZIF-67 nanoparticles exhibit an excellent cycling performance, and their catalytic efficiency did not significantly decrease in the initial 6 cycles using 0.9 M 3-cyanopyridine as the substrate. In a fed-batch reaction, NHase1229@ZIF-67 can efficiently hydrate 3-cyanopyridine to nicotinamide, and the space-time yield was calculated to be 110 g·L-1·h-1. Therefore, the cobalt-type NHase was immobilized in MOF ZIF-67, which is shown as a potential nanocatalyst for the large-scale industrial preparation of nicotinamide.

4.
Biochem Biophys Res Commun ; 519(3): 572-578, 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31537377

RESUMO

Two anthracyclines, doxorubicin and epirubicin have been widely used alone or in combination with other antitumor reagents in the chemotherapeutic treatment of various malignancies. Although therapeutic efficacy of anthracyclines has been studied extensively, precise cytotoxic mechanism of these drugs is not been completely elucidated. Here we show that epirubicin-induced degradation of transmembrane protein gp130 contributes to antitumor effect of epirubicin. gp130 is degraded by epirubicin in a proteasome- and autophagy-dependent manner. Epirubicin induces activation of p38-MK2 signaling pathway to phosphorylate gp130 at Ser 782, which results in gp130 internalization and degradation by lysosome. Although mutation of Ser 782 to Ala or Cys in gp130 upregulates global epirubicin-induced autophagy, reduced degradation of gp130 accompanied with enhanced Stat3 phosphorylation at tyrosine 705 is observed. We also show that epirubicin-resistant tumor cells express higher level of gp130. Altogether, our results indicate that degradation of gp130 and subsequent reduction of gp130-Stat3 signaling contributes to epirubicin-induced tumor cell death.

5.
3 Biotech ; 9(9): 328, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31406650

RESUMO

Chlamydomonas sp. ICE-L, which can thrive in extreme environments of the Antarctic, could represent a promising alternative for polyunsaturated fatty acid (PUFA) production. A new Δ12-fatty acid desaturase (FAD)-encoding gene (Δ 12 CiFAD), 1269 bp in size, was cloned from Chlamydomonas sp. ICE-L. Bioinformatics analysis showed that Δ 12 CiFAD-encoded protein was homologous to known FADs with conserved histidine motifs, and localized to the chloroplast. Functional analysis of Δ 12 CiFAD indicated that recombinant Synechococcus 6803 expressing Δ12CiFAD could accumulate C18:2, whereas recombinant Saccharomyces cerevisiae expressing this enzyme could not accumulate C18:2 or any other new fatty acids. These results indicate that Δ12CiFAD is a functional enzyme in the chloroplast that can adjust Chlamydomonas sp. ICE-L cell membrane fluidity to adapt to Antarctic extreme low-temperature environments, which give us insights into the frigostable and cold-resistant mechanisms of hypothermic organisms.

6.
Beilstein J Nanotechnol ; 10: 1157-1165, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31293853

RESUMO

A mild and simple method was developed to synthesize a highly efficient photocatalyst comprised of Ce-doped ZnO rods and optimal synthesis conditions were determined by testing samples with different Ce/ZnO molar ratios calcined at 500 °C for 3 hours via a one-step pyrolysis method. The photocatalytic activity was assessed by the degradation of a common dye pollutant found in wastewater, rhodamine B (RhB), using a sunlight simulator. The results showed that ZnO doped with 3% Ce exhibits the highest RhB degradation rate. To understand the crystal structure, elemental state, surface morphology and chemical composition, the photocatalysts were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM) and inductively coupled plasma emission spectroscopy (ICP), respectively. The newly developed, robust, field-only surface integral method was employed to explore the relationship between the remarkable catalytic effect and the catalyst shape and porous microstructure. The computational results showed that the dipole-like field covers the entire surface of the rod-like Ce-doped ZnO photocatalyst and is present over the entire range of wavelengths considered. The optimum degradation conditions were determined by orthogonal tests and range analysis, including the concentration of RhB and catalyst, pH value and temperature. The results indicate that the pH value is the main influential factor in the photocatalytic degradation process and the optimal experimental conditions to achieve the maximum degradation rate of 97.66% in 2 hours are as follows: concentration (RhB) = 10 mg/L, concentration (catalyst) = 0.7 g/L, pH 9.0 and T = 50 °C. These optimum conditions supply a helpful reference for large-scale wastewater degradation containing the common water contaminant RhB.

7.
Phytochem Anal ; 30(6): 710-719, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31264752

RESUMO

INTRODUCTION: The main active components in hawthorn leaves possess various biological activities such as anti-inflammatory, antioxidant, and hypolipidemic effects. Therefore, it is necessary to develop an effective and reliable extraction method to extract these active compounds from hawthorn leaves. OBJECTIVE: To establish a simple, rapid, and sensitive method for extraction and determination of polyphenolic compounds from hawthorn leaves. METHODS: In this study, a microwave-assisted reaction and extraction (MARE) combined with ultra-high-performance liquid chromatography with ultraviolet detector method was established to extract and determine the polyphenolic compounds in hawthorn leaves. The solid reagent aqueous solutions were applied as extraction solvents, preventing the use of organic solvents. The target analytes were identified by quadrupole time-of-flight tandem mass spectrometry. Several experimental parameters that can significantly affect the extraction efficiency were evaluated and optimised. RESULTS: The optimal conditions were as follows: 0.1 g of sodium carbonate was used as solid reagent, the amount of sodium borate was set at 0.01 g, extraction time was 10 min, extraction temperature was set at 50°C, pH value was adjusted to 7. The validation experiments demonstrated that the method had high sensitivity with the limits of detection in the range 26.5-37.7 ng/mL. The average recoveries ranged from 80.22% to 93.27%. CONCLUSION: In this work, the proposed MARE method was successfully applied to extract and determine polyphenolic compounds in hawthorn leaf samples. Compared with other reported methods, the present method was faster, greener, and more sensitive.


Assuntos
Crataegus/química , Micro-Ondas , Folhas de Planta/química , Concentração de Íons de Hidrogênio , Limite de Detecção , Polifenóis/análise , Reprodutibilidade dos Testes
8.
BMC Nephrol ; 20(1): 278, 2019 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-31337353

RESUMO

BACKGROUND: Chronic kidney disease (CKD) and end stage renal disease (ESRD) are not well characterized in prostate cancer patients. This study aimed to examine the clinical characteristics and postsurgical outcomes of patients with or without CKD and ESRD undergoing radical prostatectomy for prostate cancer. METHODS: This population-based, retrospective study used patient data from the Nationwide Inpatient Sample, the largest all-payer US inpatient care database. From 2005 to 2014, 136,790 male patients aged > 20 years diagnosed with prostate cancer and who received radical prostatectomy were included. Postoperative complications, postoperative acute kidney injury (AKI) and urinary complications, and length of hospital stay were compared between patients with or without underlying CKD and ESRD. RESULTS: After adjusting for relevant factors, the CKD group had a significantly higher risk of postoperative complications than the non-CKD group. In addition, the CKD group had a 5-times greater risk of postoperative AKI and urinary complications than the non-CKD group. Both CKD and ESRD groups had significantly longer hospital stays than the non-CKD group. Patients receiving RARP had a lower risk of postoperative complications than those who received open radical prostatectomy, regardless of having CKD or not. Both non-CKD and CKD patients receiving RARP had shorter hospital stays than those who received open surgery. CONCLUSIONS: Prostate cancer patients with underlying CKD had significantly greater risk of postoperative complications, postoperative AKI and urinary complications, and longer hospital stays than those without CKD. The use of RARP significantly shortened hospital stays and reduced complications for these patients.

9.
J Genet Genomics ; 46(5): 235-245, 2019 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-31186161

RESUMO

Golgi membrane protein 1 (GOLM1/GP73) is a serum marker of hepatocellular carcinoma (HCC). We have previously shown that mTOR promoted tumorigenesis of HCC through stimulating GOLM1 expression. In this study, we demonstrated that the mammalian target of rapamycin (mTOR) was a negative regulator of microRNA-145 (miR-145) expression. miR-145 inhibited GOLM1 expression by targeting a coding sequence of GOLM1 gene. GOLM1 and miR-145 were inversely correlated in human HCC tissues. GOLM1-enriched exosomes activated the glycogen synthase kinase-3ß/matrix metalloproteinases (GSK-3ß/MMPs) signaling axis of recipient cells and accelerated cell proliferation and migration. In contrast, miR-145 suppressed tumorigenesis and metastasis. We suggest that mTOR/miR-145/GOLM1 signaling pathway should be targeted for HCC treatment.

10.
Zhongguo Zhong Yao Za Zhi ; 44(4): 703-711, 2019 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-30989882

RESUMO

The consecutive monoculture obstacle is a major problem in the field of Rehmannia glutinosa( R. glutinosa),has severely declined the yield and quality of R. glutinosa. Here,using hi TAIL-PCR and RACE techniques,we have cloned the full-length transcript( 1 573 bp) of Unigene 29334_All screened by DGE as a consecutive monoculture obstacle response gene of R. glutinosa. Based on ORF Finder prediction,all ORFs detected in the full-length transcript were less than 300 nt,which suggested that the above transcript was confirmed to be a long non-coding RNA( LncRNA). With alignment in R. glutinosa transcriptome,this LncRNA was partially homologous to alanine glyoxylate transaminase 2 gene( Rg AGT2),which was named LncRNA-RgATG2. To further explore the function of LncRNA-RgAGT2,we have examined expression patterns of LncRNA-RgAGT2 and Rg AGT2 at five critical development stages( seedling,elongation,pre-expanding,mid-expanding,late-expanding) in the first and second year replanting of R. glutinosa,respectively. The results indicated that LncRNA-RgAGT2,as a potential regulator,is possible to play a vital role in Rg AGT2 expression regulation. Meanwhile,LncRNA-RgAGT2 has presented significant variation in all development stages of R. glutinosa,which could be used as a " diagnostic label" to assess consecutive monoculture obstacle. This study,for the first time,showed that LncRNA was responsible for the response and regulation of consecutive monoculture obstacle,which would be a powerful supplement to reveal the molecular mechanisms of consecutive monoculture obstacle of R. glutinosa.


Assuntos
Rehmannia , Clonagem Molecular , Expressão Gênica , RNA Longo não Codificante , Transcriptoma
11.
Chem Sci ; 10(5): 1374-1379, 2019 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-30809353

RESUMO

Nickel-rich layered transition metal oxides are attractive cathode materials for rechargeable lithium-ion batteries but suffer from inherent structural and thermal instabilities that limit the deliverable capacity and cycling performance on charging to a cutoff voltage above 4.3 V. Here we report LiNi0.90Co0.07Mg0.03O2 as a stable cathode material. The obtained LiNi0.90Co0.07Mg0.03O2 microspheres exhibit high capacity (228.3 mA h g-1 at 0.1C) and remarkable cyclability (84.3% capacity retention after 300 cycles). Combined X-ray diffraction and Cs-corrected microscopy reveal that Mg doping stabilizes the layered structure by suppressing Li/Ni cation mixing and Ni migration to interlayer Li slabs. Because of the pillar effect of Mg in Li sites, LiNi0.90Co0.07Mg0.03O2 shows decent thermal stability and small lattice variation until it is charged to 4.7 V, undergoing a H1-H2 phase transition without discernible formation of an unstable H3 phase. The results indicate that moderate Mg doping is a facile yet effective strategy to develop high-performance Ni-rich cathode materials.

12.
Opt Express ; 27(2): 1467-1478, 2019 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-30696211

RESUMO

We report the study and demonstration of a new laser pulse shaping system capable of generating linearly polarized picosecond laser pulses with variable temporal profiles including symmetric intensity distributions, as well as non-symmetric distributions, which are highly desired by various applications. It is found that both high transmittance and high stability of the shaped pulse can be achieved simultaneously when crystals are set at a specific phase delay through fine control of the crystal temperature. Although multi-crystal pulse stacking with different configurations was reported before particularly for flattop pulse generation, this new configuration leads to new opportunities for many potential applications over a wide range of laser wavelengths, pulse repetition rate, time structures and power levels. A practical double-pass temporal shaping configuration that significantly reduces the number of crystals is also proposed in this paper as a result of present study.

13.
Semin Cell Dev Biol ; 90: 168-173, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30031212

RESUMO

CCCTC-binding factor (CTCF) plays indispensable roles in transcriptional inhibition/activation, insulation, gene imprinting, and regulation of 3Dchromatin structure. CTCF contributes to formation of genome multi-dimensions, regulation of dimensional changes, or control of central signals to transcriptional networks. A large number of factors affect CTCF binding, methylation/demethylation, base mutation, or poly(adp-ribosyl)ation. CTCF is one of the most important elements in the regulation of chromatin folding by combining with CBSs in TADs in a positive-reverse or reverse-positive orders. CTCF acts as a versatile nuclear factor, a transcriptional activator or repressor, an insulator binding factor, or a regulator of genomic imprinting as required for various biological procedures. Although molecular regulatory mechanisms of CTCF in cell differentiation and disease development remains unclear, roles of CTCF in carcinogenesis have been intensively explored. There is little understanding about regulatory roles of CTCF in inflammation-associated transcriptional signaling, cell injury, organ dysfunction, and systemic responses. It is also highly expected that further in-depth studies of CTCF control mechanisms can provide better understanding of disease development and potential disease-specific biomarkers and therapeutic targets.

14.
J Biotechnol ; 291: 26-34, 2019 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-30593844

RESUMO

(R)-Pantolactone (PL) is a key chiral intermediate for the synthesis of calcium (R)-pantothenate and (R)-panthenol used as food additives. The commercial production of (R)-pantothenate is performed by the resolution of racemic pantothenate, which is synthesized through an aldol condensation and a cyanation reaction. In this study, we investigated another synthetic method of (R)-pantothenate through the stereoselective reduction of ketopantoyl lactone (KPL) by aldo-keto reductase (AKR). A series of conjugated polyketone reductases (CPRs) were discovered from GenBank database by genome mining approach. The putative CPR gene from Candida orthopsilosis Co 90-125 (CorCPR) was cloned and functionally expressed in Escherichia coli BL21 (DE3). The optimum pH and temperature of recombinant CorCPR were 6.0-7.0 and 40 ℃, respectively. The Km and vmax toward KPL were1.3 mM and 227.3 µmol/min/mg protein, respectively. The conserved sequences suggest that CorCPR belongs to AKR3C family of AKR superfamily. Furthermore, a catalytic tetrad was proposed, and the detailed mechanism was clarified by molecular docking. In a batch reaction, 50 mM KPL was reduced to (R)-PL with 99% conversion and > 99% enantiomeric excess within 5 h. The recombinant CorCPR from C. orthopsilosis shows potential application in the asymmetric synthesis of (R)-pantothenate preparation.


Assuntos
4-Butirolactona/análogos & derivados , Aldo-Ceto Redutases/metabolismo , Candida parapsilosis/enzimologia , 4-Butirolactona/metabolismo , Aldo-Ceto Redutases/genética , Catálise , Escherichia coli/genética , Genoma , Simulação de Acoplamento Molecular , NADP , Proteínas Recombinantes/metabolismo
15.
Biomed Pharmacother ; 110: 677-684, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30553194

RESUMO

Cervical spondylosis (CS), which is resulted from degeneration of cervical intervertebral disc, is a common disease seriously threatening human health and quality of life. However, there is still no effective clinic strategies for the treatment of this disease. The acupoint stimulation with needle-scalpel is a widely used approach to treat orthopedic diseases. In the present study, we evaluated the therapeutic effects of acupoint stimulation around neck with needle-scalpel on delaying the degeneration of cervical intervertebral discs and hopefully provided an approach for the precaution and early intervention of CS. We firstly established a rat model of CS by cervical static-dynamic imbalance to mimics disc degeneration and then stimulated the acupoints around neck with needle-scalpel. The cervical intervertebral disc samples were collected to measure type I and II collagen by quantitative PCR (qPCR), immunohistochemistry, and western blot. The changes in micro-structure and ultra-structure of nucleus pulposus were analyzed under the optical microscope and electron microscope respectively. Acupoint stimulation with needle-scapelon increased type I collagen production and decreased type II collagen production, and improved the micro-structure and ultra-structure of nucleus pulposus. Our results suggest that acupoint stimulation around neck with needle-scapelon could inhibit intervertebral disc degeneration through modulating the extracellular matrix collagen system and improving the changed structure of nucleus pulposus.


Assuntos
Pontos de Acupuntura , Vértebras Cervicais , Degeneração do Disco Intervertebral/metabolismo , Degeneração do Disco Intervertebral/terapia , Agulhas , Núcleo Pulposo/metabolismo , Animais , Colágeno Tipo I/metabolismo , Colágeno Tipo II/metabolismo , Feminino , Degeneração do Disco Intervertebral/patologia , Núcleo Pulposo/patologia , Núcleo Pulposo/ultraestrutura , Ratos , Ratos Sprague-Dawley
16.
Onco Targets Ther ; 11: 7787-7793, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30464526

RESUMO

Background: Phyllodes tumor (PT) is a rare breast fibroepithelial biphasic tumor composed of stromal and epithelial components. The patients suffering from this disease present with a large, round, mobile, fast-growing lump, and the giant PT of more than 10 cm in diameter is so uncommon. Surgery is regarded as the primary treatment, but curative efficiency of adjuvant chemotherapy and radiotherapy is so indefinite. Case presentation: We reported one case of a middle-aged woman with a huge borderline PT in the right breast, over 20 cm in size. The pathology of needle core biopsy of the lump was suggestive of PT of the borderline subgroup, and then she underwent mastectomy of the right breast. The patient had recovered well without any postoperative treatment until a local recurrence occurred 1 year after operation. The tumor was removed with lumpectomy, which was pathologically diagnosed as malignant PT. We followed up her by telephone and heard about her postoperative adjuvant radiotherapy and chemotherapy, as well as her well recovery. Conclusion: The pathology of PT with low incidence is mostly benign, but local recurrence is common, and the histopathology progresses toward worsen trend. Besides, due to the difficulty in precise diagnosis of the borderline PTs, it is recommended that this subtype of patients should undergo total mastectomy. Although the curative effect of postoperative treatment has not been recognized internationally, patients, especially those with huge tumors, may benefit from these treatments.

17.
Rev Sci Instrum ; 89(7): 075106, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30068117

RESUMO

Measuring the pressure of a gasket (Pg) and cell (Pc) in situ is the key point to understanding the mechanism of pressure-generation and pressure-seal for the widely used large volume cubic press. However, it is a challenge to measure Pg due to the large deformation in the gasket zone and the complex rheological behavior of the pressure transmitting medium. Herein, a method of in situ electric resistance measurement has been developed to measure Pg. The open circuit failure in electric resistance measurement was avoided by using powder electrodes which could match the mould-pressed pyrophyllite cube in rheological behavior during compression. The relationships between press-load vs. Pc and press-load vs. Pg were obtained through in situ electric resistance measurements of bismuth, thallium, barium, and manganin. It was found that Pg exceeded Pc at around 5 GPa and Pc generated in the large volume cubic press was limited to the rapid rise of Pg above 5 GPa. Furthermore, the maximum ΔP (ΔP = Pc - Pg) above 0.9 GPa has been observed when Pc was released to a pressure range of 3-4 GPa, and this also leads to a large probability of high pressure cavity seal failure.

18.
Oncol Lett ; 15(5): 7639-7648, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29725463

RESUMO

DNA methylation is closely associated with aberrant epigenetic changes. Previous studies have identified various genes associated with non-small cell lung cancer (NSCLC), but the precise combination responsible for its etiology is still debated. The aim of the present study was to select a new set of NSCLC-related genes using methylation-sensitive high-resolution melting. The promoter methylation status of six selected genes, consisting of protocadherin γ subfamily B, 6 (PCDHGB6), homeobox A9 (HOXA9), O6-methylguanine-DNA methyltransferase (MGMT), microRNA (miR)-126, suppressor of cytokine signaling 3 (SOCS3) and Ras association domain family member 5, also termed NORE1A, was evaluated in 54 NSCLC patients. From these samples, genome-wide DNA was extracted and bisulfite conversion was performed along with fluorogenic quantitative polymerase chain reaction to detect methylation values of the six selected promoters. The present results revealed frequent methylation on PCDHGB6, HOXA9 and miR-126, which contrasted with infrequent methylation on MGMT. The results indicated no methylation on either SOCS3 or NORE1A. The sensitivity and specificity of the methylation assessment were 85.2 and 81.5%, respectively, and the analysis results were validated by pyrosequencing. Furthermore, minute comparison of the association between DNA methylation and clinical features was performed. Overall, these results may provide potential information for the development of better clinical diagnostics and more targeted and effective therapies for NSCLC.

19.
Mol Biotechnol ; 60(1): 21-30, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29138983

RESUMO

The α-carbonic anhydrase (α-CA) is a zinc ion-containing enzyme that catalyzes the hydration of carbon dioxide. In this paper, a full-length α-CA gene was cloned from Chlamydomonas sp. ICE-L using RT-PCR and RACE-PCR for bioinformatic analysis. The α-CA open reading frame obtained by PCR was cloned into a vector and transformed into Escherichia coli to generate α-CA-producing bacteria. The α-CA was highly expressed upon induction with isopropyl-ß-d-thiogalactoside (IPTG) at a final concentration of 0.8 mM. A single band with a molecular weight of approximate 40 kDa expressed in the recombinant E. coli strain harboring the α-CA vector was observed in SDS-PAGE analysis. The carbon dioxide hydration activity and esterase activity of α-CA expressed by the recombinant strain were 0.404 U/mg and 0.319 U, respectively. In addition, three conditions, temperature, salinity and UVB radiation exposure, were selected to analyze α-CA transcription levels by qRT-PCR. The results suggested UVB exposure increased the expression of relative mRNA; meanwhile, the α-CA mRNA expression was rapidly induced by temperature and salinity stress, indicating that Chlamydomonas sp. ICE-L might modulate the α-CA mRNA expression to adapt to the extreme environments.


Assuntos
Anidrases Carbônicas/genética , Anidrases Carbônicas/metabolismo , Chlamydomonas/enzimologia , Dióxido de Carbono/metabolismo , Chlamydomonas/genética , Clonagem Molecular , Eletroforese em Gel de Poliacrilamida , Escherichia coli/genética , Filogenia , Temperatura Ambiente
20.
Adv Exp Med Biol ; 1038: 9-22, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29178066

RESUMO

Mitochondrial DNA (mtDNA) variations are increasingly discovered and expected to be potential biomarkers to monitor severity, duration, stage, response to therapy, and prognosis in patients with lung cancer. The present article illustrates alterations of mtDNA in lung cancer, including alterations of mtDNA copy number and sequence mutations, as well as their possible mechanisms for carcinogenesis and development of lung cancer. The clear and comprehensive relationships between mtDNA variations and lung cancer are to be further confirmed to benefit effective strategies for lung cancer diagnosis and therapy.


Assuntos
Transformação Celular Neoplásica , DNA Mitocondrial , DNA de Neoplasias , Neoplasias Pulmonares , Mitocôndrias , Animais , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , DNA de Neoplasias/genética , DNA de Neoplasias/metabolismo , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Mitocôndrias/genética , Mitocôndrias/metabolismo , Mitocôndrias/patologia
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