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Owing to the Fermi pinning effect arose in the metal electrodes deposition process, metal-semiconductor contact is always independent on the work function, which challenges the next-generation optoelectronic devices. In this work, a metal-assisted transfer approach is developed to transfer Bi2 O2 Se nanosheets onto the pre-deposited metal electrodes, benefiting to the tunable metal-semiconductor contact. The success in Bi2 O2 Se nanosheets transfer is contributed to the stronger van der Waals adhesion of metal electrodes than that of growth substrates. With the pre-deposited asymmetric electrodes, the self-powered near-infrared photodetectors are realized, demonstrating low dark current of 0.04 pA, high Ilight /Idark ratio of 380, fast rise and decay times of 4 and 6 ms, respectively, under the illumination of 1310 nm laser. By pre-depositing the metal electrodes on polyimide and glass, high-performance flexible and omnidirectional self-powered near-infrared photodetectors are achieved successfully. This study opens up new opportunities for low-dimensional semiconductors in next-generation high-performance optoelectronic devices.
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Power consumption makes next-generation large-scale photodetection challenging. In this work, the source-gated transistor (SGT) is adopted first as a photodetector, demonstrating the expected low power consumption and high photodetection performance. The SGT is constructed by the functional sulfur-rich shelled GeS nanowire (NW) and low-function metal, displaying a low saturated voltage of 0.61 V ± 0.29 V and an extremely low power consumption of 7.06 pW. When the as-constructed NW SGT is used as a photodetector, the maximum value of the power consumption is as low as 11.96 nW, which is far below that of the reported phototransistors working in the saturated region. Furthermore, benefiting from the adopted SGT device, the photodetector shows a high photovoltage of 6.6 × 10-1 V, a responsivity of 7.86 × 1012 V W-1, and a detectivity of 5.87 × 1013 Jones. Obviously, the low power consumption and excellent responsivity and detectivity enabled by NW SGT promise a new approach to next-generation, high-performance photodetection technology.
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The surface Fermi level pinning effect promotes the formation of metal-independent Ohmic contacts for the high-speed GaSb nanowires (NWs) electronic devices, however, it limits next-generation optoelectronic devices. In this work, lead-free all-inorganic perovskites with broad bandgaps and low work functions are adopted to decorate the surfaces of GaSb NWs, demonstrating the success in the construction of Schottky-contacts by surface engineering. Benefiting from the expected Schottky barrier, the dark current is reduced to 2 pA, the Ilight /Idark ratio is improved to 103 and the response time is reduced by more than 15 times. Furthermore, a Schottky-contacted parallel array GaSb NWs photodetector is also fabricated by the contact printing technology, showing a higher photocurrent and a low dark current of 15 pA, along with the good infrared photodetection ability for a concealed target. All results guide the construction of Schottky-contacts by surface decorations for next-generation high-performance III-V NWs optoelectronics devices.
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The relative low hole mobility of p-channel building block device challenges the continued miniaturization of modern electronic chips. Metal-semiconductor junction is always an efficient strategy to control the carrier concentration of channel semiconductor, benefiting the carrier mobility regulation of building block device. In this work, complementary metal oxide semiconductor (CMOS)-compatible metals are selected to deposit on the surface of the important p-channel building block of GaSb nanowire field-effect-transistors (NWFETs), demonstrating the efficient strategy of hole mobility enhancement by metal-semiconductor junction. When deposited with lower work function metal of Al, the peak hole mobility of GaSb NWFET can be enhanced to as high as ≈3372 cm2 V-1 s-1 , showing three times than the un-deposited one. The as-studied metal-semiconductor junction is also efficient for the hole mobility enhancement of other p-channel devices, such as GaAs NWFET, GaAs film FET, and WSe2 FET. With the enhanced mobility, the as-constructed CMOS inverter shows good invert characteristics, showing a relatively high gain of ≈18.1. All results may be regarded as important advances to the next-generation electronics.
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Weak n-type characteristics or poor p-type characteristics are limiting the applications of binary semiconductors based on ambipolar field-effect transistors (FETs). In this work, a ternary alloy of In0.2Ga0.8As nanowires (NWs) is successfully prepared using a Ni catalyst during a typical solid-source chemical-vapor-deposition process to balance the weak n-type conduction behavior in ambipolar GaAs NWFETs and the poor p-type conduction behavior in ambipolar InAs NWFETs. The presence of ambipolar transport, contributed by a native oxide shell and the body defects of the prepared In0.2Ga0.8As NWs, is confirmed by the constructed back-gated NWFETs. As demonstrated by photoluminescence, the bandgap of the prepared In0.2Ga0.8As NWs is 1.28 eV, offering the promise of application in near-infrared (NIR) photodetection. Under 850 nm laser illumination, the fabricated ambipolar NWFETs show extremely low dark currents of 50 pA and 0.5 pA when positive and negative gate voltages are applied, respectively. All the results demonstrate that with careful design of the surface oxide layer and the body defects, NWs are suitable for use in next-generation optoelectronic devices.
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In the past decades, defect engineering has become an effective strategy to significantly improve the hydrogen evolution reaction (HER) efficiency of electrocatalysts. In this work, a facile chemical vapor deposition (CVD) method is firstly adopted to demonstrate defect engineering in high-efficiency HER electrocatalysts of vanadium diselenide nanostructures. For practical applications, the conductive substrate of carbon cloth (CC) is selected as the growth substrate. By using a four-time CVD method, uniform three-dimensional microflowers with defect-rich small nanosheets on the surface are prepared directly on the CC substrate, displaying a stable HER performance with a low Tafel slope value of 125 mV dec-1and low overpotential voltage of 295 mV at a current density of 10 mA cm-2in alkaline electrolyte. Based on the results of x-ray photoelectron spectra and density functional theory calculations, the impressive HER performance originates from the Se vacancy-related active sites of small nanosheets, while the microflower/nanosheet homoepitaxy structure facilitates the carrier flow between the active sites and conductive substrate. All the results present a new route to achieve defect engineering using the facile CVD technique, and pave a novel way to prepare high-activity layered electrocatalysts directly on a conductive substrate.
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Owing to the relatively low hole mobility, the development of GaSb nanowire (NW) electronic and photoelectronic devices has stagnated in the past decade. During a typical catalyst-assisted chemical vapor deposition (CVD) process, the adopted metallic catalyst can be incorporated into the NW body to act as a slight dopant, thus regulating the electrical properties of the NW. In this work, we demonstrate the use of Sn as a catalyst and dopant for GaSb NWs in the surfactant-assisted CVD growth process. The Sn-catalyzed zinc-blende GaSb NWs are thin, long, and straight with good crystallinity, resulting in a record peak hole mobility of 1028 cm2 V-1 s-1. This high mobility is attributed to the slight doping of Sn atoms from the catalyst tip into the NW body, which is verified by the red-shifted photoluminescence peak of Sn-catalyzed GaSb NWs (0.69 eV) compared with that of Au-catalyzed NWs (0.74 eV). Furthermore, the parallel array NWs also show a high peak hole mobility of 170 cm2 V-1 s-1, a high responsivity of 61 A W-1, and fast rise and decay times of 195.1 and 380.4 µs, respectively, under the illumination of 1550 nm infrared light. All of the results demonstrate that the as-prepared Sn-catalyzed GaSb NWs are promising for application in next-generation electronics and optoelectronics.
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Owing to the high mobility, narrow bandgap, strong spin-orbit coupling and large g-factor, Sb-based III-V nanowires (NWs) attracted significant interests in high speed electronics, long-wavelength photodetectors and quantum superconductivity in the past decade. In this review, we aim to give an integrated summarization about the recent advances in binary as well as ternary Sb-based III-V NWs, starting from the fundamental properties, NWs growth mechanism, typical synthetic methods to their applications in transistors, photodetectors, and Majorana fermions detection. Up to now, famous NWs growth techniques of solid-source chemical vapor deposition (CVD), molecular beam epitaxy, metal organic vapor phase epitaxy and metal organic CVD etc have been adopted and developed for the controllable growth of Sb-based III-V NWs. Several parameters including heating temperature, III/V ratio of source materials, growth temperature, catalyst size and kinds, and growth substrate play important roles on the morphology, position, diameter distribution, growth orientation and crystal phase of Sb-based III-V NWs. Furthermore, we discuss the photoelectrical applications of Sb-based III-V NWs such as field-effect-transistors, tunnel diode, low-power inverter, and infrared detectors etc. Importantly, due to the strongest spin-orbit interaction and giant g-factor among all III-V semiconductors, InSb with the geometry of one-dimension NW is considered as the most promising candidate for the detection of Majorana fermions. In the end, we also summarize the main challenges remaining in the field and put forward some suggestions for the future development of Sb-based III-V NWs.
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Curcumin, a dietary supplement or herbal medicine from Curcuma longa, has shown antitumor activity in different cancer cell lines and clinical trials. CA916798, a novel protein, is overexpressed in multidrug-resistant tumor cells. This study aimed to assess the effects of curcumin on regulating chemosensitivity in cisplatin-resistant non-small cell lung cancer (NSCLC) cells in vitro and to explore the underlying molecular mechanisms. Human cisplatin-sensitive A549 and cisplatin-resistant A549/CDDP lung adenocarcinoma cells were treated with curcumin to assess cell viability and gene modulations using quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and western blotting. CA916798 shRNA and point mutations were used to assess the CA916798 functions and phosphorylation sites. Bisdemethoxycurcumin sensitized cisplatin-resistant lung cancer cells to various chemotherapeutic agents, including cisplatin. Bisdemethoxycurcumin reduced the levels of CA916798 mRNA and protein in A549 and A549/CDDP cells, while it also suppressed phosphatidylinositol-3-kinase (PI3K)/AKT signaling. CA916798, as a downstream gene, interacted with AKT after bisdemethoxycurcumin treatment in A549 and A549/CDDP cells. Moreover, A549/CDDP cells expressing the point-mutated CA916798-S20D protein were more resistant to cisplatin and bisdemethoxycurcumin, whereas tumor cells expressing CA916798-S20A, CA916798-S31A, CA916798-S60A, CA916798-S93A, or CA916798-T97A (different sites of amino acid phosphorylation) showed similar sensitivity or resistance to cisplatin and bisdemethoxycurcumin, compared with the control cells. Bisdemethoxycurcumin is able to sensitize cisplatin-resistant NSCLC cells to chemotherapeutic agents by inhibition of CA916798 and PI3K/AKT activities. Moreover, phosphorylation of CA916798 at the S20 residue plays a critical role in mediating bisdemethoxycurcumin antitumor activity.
Assuntos
Adenocarcinoma/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Curcumina/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Neoplasias Pulmonares/tratamento farmacológico , Proteínas de Neoplasias/metabolismo , Transdução de Sinais/efeitos dos fármacos , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Adenocarcinoma de Pulmão , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Nus , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismoRESUMO
Amorphous In2O3 film is emerging as a promising oxide semiconductor for next-generation electronics and optoelectronics owing to high mobility and wide band gap. However, the persistent photocurrent phenomenon and high carrier concentration in amorphous In2O3 film are challenging the photodetection performances, resulting in a long response time and low Ilight/Idark ratio. In this work, the In2O3/PbI2 heterojunction is constructed by an all-solution synthesis process to inhibit the persistent photocurrent phenomenon and large dark current. Benefiting from the built-in electric field at the heterojunction interface, the In2O3/PbI2 heterojunction photodetector exhibits excellent self-powered photodetection performances with an ultralow dark current of 10-12 A, a high Ilight/Idark ratio of 104, and fast response times of 0.6/0.6 ms. Furthermore, the entire solution synthesis process and amorphous characteristics enable the fabrication of an In2O3/PbI2 heterojunction photodetector on arbitrary substrates to realize specific functions. When configured onto the polyimide substrate, the In2O3/PbI2 heterojunction photodetector shows excellent mechanical flexibility, bending endurance, and photoresponse stability. When implanted onto the transparent substrate, the In2O3/PbI2 heterojunction photodetector exhibits an outstanding omnidirectional self-powdered photodetection performance and imaging capability. All results pave the way for an all-solution-processed amorphous In2O3 film in advanced high-performance photodetectors.
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Constructing a unipolar heterojunction is an effective energy band engineering strategy to improve the performance of photoelectric devices, which could suppress dark current and enhance detectivity by modulating the transfer of carriers. In this work, unipolar heterojunctions of Si/PbI2 and GaSb/PbI2 are constructed successfully for high-performance self-powered near-ultraviolet photodetection. Owing to the unique band offset of unipolar heterojunctions, the transport of holes is blocked, and only photogenerated electrons in PbI2 can flow unimpeded under the driving force of the built-in electric field. Thus, the recombination of photogenerated electron-hole pairs is suppressed, contributing to high-performance near-ultraviolet photodetection. The as-fabricated Si/PbI2 self-powered near-ultraviolet photodetector exhibits a low dark current of 10-13 A, a high Ilight/Idark ratio of 104, and fast response times of 26/24 ms, which are much better than those of the PbI2 metal-semiconductor-metal photodetector. Furthermore, the as-fabricated GaSb/PbI2 unipolar heterojunction photodetector also exhibits impressive self-powered near-ultraviolet photodetection behaviors. Evidently, this work shows the potential of unipolar heterojunctions for next-generation Si-based and GaSb-based high-performance photodetection.
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Due to their persistent photoconductivity, amorphous metal oxide thin films are promising for construction of artificial visual systems. In this work, large-scale, uniformly distributed amorphous InGaO thin films with an adjustable In/Ga ratio and thickness are prepared successfully by a low-cost environmentally friendly and easy-to-handle solution process for constructing artificial visual systems. With the increase of the In/Ga ratio and film thickness, the number of oxygen vacancies increases, along with the increase of post-synaptic current triggered by illumination, benefiting the transition of short-term plasticity to long-term plasticity. With an optimal In/Ga ratio and film thickness, the conductance response difference at a decay of 0 s between the 1st and the 10th views of a 5 × 5 array InGaO thin film transistor is up to 2.88 µA, along with an increase in the Idecay 30s/Idecay 0s ratio from 45.24% to 53.24%, resulting in a high image clarity and non-volatile artificial visual memory. Furthermore, a three-layer artificial vision network is constructed to evaluate the image recognition capability, exhibiting an accuracy of up to 91.32%. All results promise low-cost and easy-to-handle amorphous InGaO thin films for future visual information processing and image recognition.
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The inhomogeneous native oxide shells on the surfaces of III-V group semiconductors typically yield inferior and unstable electrical properties metrics, challenging the development of next-generation integrated circuits. Herein, the native GaOx shells are profitably utilized by a simple in-situ thermal annealing process to achieve high-performance GaSb nanowires (NWs) field-effect-transistors (FETs) with excellent bias-stress stability and synaptic behaviors. By an optimal annealing time of 5 min, the as-constructed GaSb NW FET demonstrates excellent stability with a minimal shift of transfer curve (ΔVth ≈ 0.54 V) under a 60 min gate bias, which is far more stable than that of pristine GaSb NW FET (ΔVth ≈ 8.2 V). When the high bias-stress stability NW FET is used as the chargeable-dielectric free synaptic transistor, the typical synaptic behaviors, such as short-term plasticity, long-term plasticity, spike-time-dependent plasticity, and reliable learning stability are demonstrated successfully through the voltage tests. The mobile oxygen ion in the native GaOx shell strongly offsets the trapping states and leads to enhanced bias-stress stability and charge retention capability for synaptic behaviors. This work provides a new way of utilizing the native oxide shell to realize stable FET for chargeable-dielectric free neuromorphic computing systems.
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ß-Ga2O3 nanostructures are attractive wide-band-gap semiconductor materials as they exhibit promising photoelectric properties and potential applications. Despite the extensive efforts on ß-Ga2O3 nanowires, investigations into ß-Ga2O3 nanotubes are rare since the tubular structures are hard to synthesize. In this paper, we report a facile method for fabricating ß-Ga2O3 nanotubes using pre-synthesized GaSb nanowires as sacrificial templates. Through a two-step heating-treatment strategy, the GaSb nanowires are partially oxidized to form ß-Ga2O3 shells, and then, the residual inner parts are removed subsequently in vacuum conditions, yielding delicate hollow ß-Ga2O3 nanotubes. The length, diameter, and thickness of the nanotubes can be customized by using different GaSb nanowires and heating parameters. In situ transmission electron microscopic heating experiments are performed to reveal the transformation dynamics of the ß-Ga2O3 nanotubes, while the Kirkendall effect and the sublimation process are found to be critical. Moreover, photoelectric tests are carried out on the obtained ß-Ga2O3 nanotubes. A photoresponsivity of ~25.9 A/W and a detectivity of ~5.6 × 1011 Jones have been achieved with a single-ß-Ga2O3-nanotube device under an excitation wavelength of 254 nm.
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Growing high-quality core-shell heterostructure nanowires is still challenging due to the lattice mismatch issue at the radial interface. Herein, a versatile strategy is exploited for the lattice-mismatch-free construction of III-V/chalcogenide core-shell heterostructure nanowires by simply utilizing the surfactant and amorphous natures of chalcogenide semiconductors. Specifically, a variety of III-V/chalcogenide core-shell heterostructure nanowires are successfully constructed with controlled shell thicknesses, compositions, and smooth surfaces. Due to the conformal properties of obtained heterostructure nanowires, the wavelength-dependent bi-directional photoresponse and visible light-assisted infrared photodetection are realized in the type-I GaSb/GeS core-shell heterostructure nanowires. Also, the enhanced infrared photodetection is found in the type-II InGaAs/GeS core-shell heterostructure nanowires compared with the pristine InGaAs nanowires, in which both responsivity and detectivity are improved by more than 2 orders of magnitude. Evidently, this work paves the way for the lattice-mismatch-free construction of core-shell heterostructure nanowires by chemical vapor deposition for next-generation high-performance nanowire optoelectronics.
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Realizing omnidirectional self-powered photodetectors is central to advancing next-generation portable and smart photodetector systems. However, the traditional omnidirectional photodetector is typically achieved by integrating complex hemispherical microlens on multiple photodetectors, which makes the detection system cumbersome and restricts its application in the portable field. Here, facile and high-performance flexible omnidirectional self-powered photodetectors are achieved by solution-processed two-dimensional (2D) layered PbI2 nanoplates on transparent conducting substrates. Characterization of PbI2 nanoplates microstructural/compositional and their photodetection properties have been systematically characterized. Under the irradiation of a 405 nm laser, the photodetectors exhibit an impressively low dark current of 10-13 A, a high light on/off ratio up to 106, and a fast rise/decay response time of 2/3 ms. Importantly, when light irradiates the photodetector at 5°, it can still maintain high photodetection properties, realizing almost 360° omnidirectional self-powered photodetection. What is more, these self-powered photodetectors exhibit robust omnidirectional photoresponse stability of flexibility even after bending for 1200 cycles. Thus, this work broadens the applicability of 2D layered nanoplates for further extending its applications in advanced optoelectronic devices.
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The negative photoconductivity (NPC) effect originating from the surface shell layer has been considered as an efficient approach to improve the performance of optoelectronic nanodevices. However, a scientific design and precise growth of NPC-effect-caused shell during nanowire (NW) growth process for achieving high-performance photodetectors are still lacking. In this work, GeS NWs with a controlled sulfur-rich shell, diameter, and length are successfully prepared by a simple chemical vapor deposition method. As checked by transmission electron microscopy, the thickness of the sulfur-rich shell ranges from 10.5 ± 1.5 to 13.4 ± 2.5 nm by controlling the NW growth time. The composition of the sulfur-rich shell is studied by X-ray photoelectron spectroscopy, showing the decrease of S in the GeSx shell from the surface to core. When configured into the well-known phototransistor, a featured NPC effect is observed, benefiting the high-performance photodetector with high responsivity of 105 A·W-1 and detectivity of 1012 Jones for λ = 405 nm with ultralow intensity of 0.04 mW·cm-2. However, the thicker-shell NW phototransistor shows an unstable photodetector behavior with smaller negative photocurrent because of more hole-trapping states in the thicker shell. All results suggest a careful design and controlled growth of an NPC-effect-caused shell for future optoelectronic applications.
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PURPOSE AND METHODS: To investigate the doses of total body (TBI) and whole abdominal irradiation (WAI) induced lethal intestinal injury, healthy C57BL/6 J mice were divided randomly into 7 groups: control group; 6, 7, and 8 Gy TBI groups; and 5, 10, and 15 Gy WAI groups. The survival length, general conditions, body weight, daily food and water intake of the mice and the histopathological changes of small intestine were observed. RESULTS: Lethal injury among C57BL/6 J mice was caused by ≥6 Gy TBI and 15 Gy WAI. Their body weight and food intake decreased, the structure of their small intestinal villi was destroyed, and the number of surviving crypts per circumference of the jejunum decreased in ≥6 Gy TBI groups and 15 Gy WAI group. The mice in the 10 Gy WAI group significantly lost weight within 5 days but recovered slowly thereafter. They also had poor appetite and reversibly damaged intestinal mucosa. CONCLUSIONS: Nonlethal intestinal injury could be induced by 10 Gy WAI, whereas lethal intestinal injury could be triggered by ≥6 Gy TBI and >15 Gy WAI in mice. Our results provided a basis for establishing radiation-induced intestinal injury models with C57BL/6 J mice.
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To investigate the association between polymorphisms of the COL1A1 gene and liver cirrhosis. A total of 111 liver cirrhotic patients and 95 matched controls were recruited. Polymorphisms -1997T>G, -1663 ins/del T and -1363C>G of the COL1A1 gene were detected by direct sequencing. The activities of the putative promoters containing these polymorphisms were analyzed by means of the reporter gene system. No polymorphism at -1663 ins/del T was observed in any subject. Linkage disequilibrium was shown between -1997T>G and -1363C>G. The frequency of haplotype -1997T/-1363C was significantly higher in patients than that in controls. The putative promoters containing -1997T/-1363C resulted in higher reporter gene activity in LX-2. Strong transcriptional inhibition by IFN gamma was shown in both cells. The T allele at -1997 of COL1A1 is crucial to the increased transcriptional activity. COL1A1 gene polymorphism might be associated with liver fibrogenesis.
Assuntos
Colágeno Tipo I/genética , Hepatite B Crônica/complicações , Cirrose Hepática/genética , Adulto , Idoso , Alelos , Povo Asiático , China , Cadeia alfa 1 do Colágeno Tipo I , Feminino , Expressão Gênica/efeitos dos fármacos , Frequência do Gene , Genes Reporter , Genótipo , Humanos , Mutação INDEL , Interferon gama/farmacologia , Desequilíbrio de Ligação , Cirrose Hepática/virologia , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Regiões Promotoras Genéticas , Adulto JovemRESUMO
BACKGROUND AND AIMS: Transforming growth factor beta1 (TGFbeta1) acts as an important profibrogenic cytokine in liver fibrogenesis. The aim of this study was to explore the association between TGFbeta1 gene polymorphisms and liver cirrhosis. METHODS: Totally 118 Chinese suffering from liver cirrhosis induced by HBV infection and 104 healthy controls were recruited. The polymorphisms at positions -988, -800, -509 and codon10, codon25, codon263 of the TGFbeta1 gene were genotyped by ARMS-PCR or LightCycler. Enzyme immunoassay was used for TGFbeta1 measurement. The promoter activities and DNA-binding capacities containing -509C>T were analyzed by reporter gene and EMSA. RESULTS: The allele frequencies of CAT -509 and of T at codon10 were elevated in patients at severe Child-Pugh grade. Elevated concentrations of TGFbeta1 were observed in patients, especially in those with -509CC/CT and codon10 TT/TC. Flanking sequences containing -509C showed higher promoter activities than -509T. EMSA showed one nucleotide change at -509C>T influenced nuclear protein binding to the putative binding site. CONCLUSIONS: The C allele at -509 and the T allele at codon10 could play important roles in progression of liver cirrhosis. The C allele at -509 mediates higher transcriptional activity than the T allele providing a potential explanation for the clinical findings.