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1.
Zhonghua Jie He He Hu Xi Za Zhi ; 47(4): 339-345, 2024 Apr 12.
Artigo em Chinês | MEDLINE | ID: mdl-38599809

RESUMO

Objective: To construct and characterize conditional Src homology region 2 protein tyrosine phosphatase 1 (SHP-1) knockout mice in airway epithelial cells and to observe the effect of defective SHP-1 expression in airway epithelial cells on the emphysema phenotype in chronic obstructive pulmonary disease (COPD). Methods: To detect the expression of SHP-1 in the airway epithelium of COPD patients. CRISPR/Cas9 technology was used to construct SHP-1flox/flox transgenic mice, which were mated with airway epithelial Clara protein 10-cyclase recombinase and estrogen receptor fusion transgenic mice (CC10-CreER+/+), and after intraperitoneal injection of tamoxifen, airway epithelial SHP-1 knockout mice were obtained (SHP-1flox/floxCC10-CreER+/-, SHP-1Δ/Δ). Mouse tail and lung tissue DNA was extracted and PCR amplified to discriminate the genotype of the mice; the knockout effect of SHP-1 gene in airway epithelial cells was verified by qRT-PCR, Western blotting, and immunofluorescence. In addition, an emphysema mouse model was constructed using elastase to assess the severity of emphysema in each group of mice. Results: Airway epithelial SHP-1 was significantly downregulated in COPD patients. Genotyping confirmed that SHP-1Δ/Δ mice expressed CC10-CreER and SHP-1-flox. After tamoxifen induction, we demonstrated the absence of SHP-1 protein expression in airway epithelial cells of SHP-1Δ/Δ mice at the DNA, RNA, and protein levels, indicating that airway epithelial cell-specific SHP-1 knockout mice had been successfully constructed. In the emphysema animal model, SHP-1Δ/Δ mice had a more severe emphysema phenotype compared with the control group, which was manifested by disorganization of alveolar structure in lung tissue and rupture and fusion of alveolar walls to form pulmonary alveoli. Conclusions: The present study successfully established and characterized the SHP-1 knockout mouse model of airway epithelial cells, which provides a new experimental tool for the in-depth elucidation of the role of SHP-1 in the emphysema process of COPD and its mechanism.


Assuntos
Enfisema , Doença Pulmonar Obstrutiva Crônica , Enfisema Pulmonar , Humanos , Camundongos , Animais , Enfisema Pulmonar/genética , Enfisema Pulmonar/metabolismo , Doença Pulmonar Obstrutiva Crônica/metabolismo , Células Epiteliais/metabolismo , Camundongos Transgênicos , Camundongos Knockout , Fenótipo , DNA , Tamoxifeno
2.
Zhonghua Yi Xue Za Zhi ; 101(30): 2382-2386, 2021 Aug 10.
Artigo em Chinês | MEDLINE | ID: mdl-34404131

RESUMO

Objective: To investigate the effect of axillary lymph node status on the prognosis of different types of invasive breast cancer. Methods: Patients with invasive breast cancer of different molecular subtypes diagnosed in the breast cancer prevention and treatment center of Beijing Cancer Hospital from January 2000 to July 2011 were collected as a historical cohort, and the influence of lymph node status on the prognosis of different types of breast cancer was analyzed. Results: A total of 4 269 female breast cancer patients with molecular subtypes [aged (50.8±11.2) years] information and 3 824 female breast cancer patients with complete axillary lymph node status information [aged (50.5±10.9) years] were included in the study, including 3 135 cases with both molecular subtypes and lymph node status information. The 10-year event free survival (EFS) rates of hormone receptor (HR)+/human epidermal growth factor receptor-2(HER2)-, HR-/HER2-and HER2+were 82.2%, 79.0% and 76.8%, respectively; the 10-year overall survival (OS) rates were 88.1%, 83.1% and 84.4%, respectively, and the differences of 3 molecular subtypes in EFS and OS were statistically significant (both P<0.001). The 10-year EFS rate of lymph node positive and negative patients was 68.8% and 88.2%, respectively; the 10-year OS rate was 76.7% and 92.5%, respectively, and the differences of lymph node status in EFS and OS were statistically significant (both P<0.001). In lymph node negative subgroup, 3 subtypes showed similar EFS and OS rate (both P>0.05); In lymph node positive subgroup, 3 subtypes showed significantly different EFS and OS (both P<0.05). No modification effect was detected of lymph node status on the correlation of molecular subtypes and EFS, DDFS and OS(all Pinteractive>0.1). Conclusions: Different molecular subtypes of breast cancer have different prognosis. Compared with molecular subtype, lymph node status may be a more important prognostic factor.


Assuntos
Neoplasias da Mama , Axila , Intervalo Livre de Doença , Feminino , Humanos , Linfonodos , Prognóstico , Receptor ErbB-2
3.
Zhonghua Wai Ke Za Zhi ; 59(2): 127-133, 2021 Feb 01.
Artigo em Chinês | MEDLINE | ID: mdl-33378805

RESUMO

Objective: To examine the difference of long-term recurrence rate and survivals between the young patients and the old patients undergoing breast conserving therapy (BCT). Methods: Women with primary invasive breast cancer receiving BCT between December 1999 and December 2014 were selected retrospectively from the database of Breast Cancer Center, Peking University Cancer Hospital & Institute. The median age of all patients was 47 years (range: 21 to 91 years). The cases were categorized according to age at diagnosis into two subgroups: the ≤40 years group and the>40 years group. A total of 2 778 patients were included: 677 patients in the ≤40 years group and 2 101 patients in the >40 years group. Clinicopathological characteristics between two groups were compared. The recurrence rate and survival were calculated using the Kaplan-Meier method. The differences of outcomes were compared in different aged groups using the Log-rank test. Factors affecting local recurrence, distant disease-free survival (DDFS), disease-free survival (DFS), and breast cancer-specific survival (BCSS) were assessed by multivariable Cox proportional hazard models. Results: Proportions of T1 (301/677 vs. 1 160/2 101, χ²=37.660, P<0.01), involved lymph node (314/677 vs. 713/2 101, χ²=34.966, P<0.01) hormone receptor-negative (490/677 vs. 1 581/2 101, χ²=6.981, P=0.030) and neoadjuvant chemotherapy (413/677 vs. 1 010/2 101, χ²=34.272,P<0.01)in the ≤40 years group were higher than that in the>40 years group. Median follow-up duration was 102 months. No significant difference in 10-year local recurrence was found between the two groups (2.5% vs. 1.6%, P=0.147). Ten-year DDFS rate in the ≤40 years group and in the>40 years group was 90.6% and 95.3%, respectively (P<0.01). Ten-year DFS rate in the ≤40 years group and in the>40 years group was 86.5% and 91.1%, respectively (P=0.001). Ten-year BCSS rate in the ≤40 years group and in the >40 years group was 91.0% and 93.7%, respectively (P=0.105). Age was not the prognosis factor of local recurrence. Lymph node status (positive vs. negative: HR=2.73, 95%CI: 1.94 to 3.84, P<0.01), age (≤40 years vs.>40 years: HR=1.73, 95%CI: 1.24 to 2.42, P=0.001) and T stage (>2 cm vs. ≤2 cm: HR=1.61, 95%CI: 1.14 to 2.28, P=0.001) were the prognosis factors of DDFS, and also for DFS. Hormone receptor status (positive vs. negative: HR=0.54, 95%CI: 0.39 to 0.74, P<0.01), lymph node status (positive vs. negative: HR=2.94, 95%CI: 2.12 to 4.07, P<0.01) and T stage (>2 cm vs. ≤2 cm: HR=1.45, 95%CI: 1.05 to 2.01, P=0.025) were the prognosis factors of BCSS. Conclusions: The risk of local recurrence was similar between ≤40 years patient and >40 years patients receiving breast conserving therapy. Worse survivals in the ≤40 years group were found comparing to those in the >40 years group.


Assuntos
Neoplasias da Mama , Mastectomia Segmentar , Recidiva Local de Neoplasia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Intervalo Livre de Doença , Feminino , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Adulto Jovem
4.
Phys Chem Chem Phys ; 22(41): 23665-23677, 2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-33112338

RESUMO

Antimonene nanotubes, a class of important derivatives of the 2D counterpart (Sb monolayer), with transition metal (TM) atom adsorption were investigated systematically based on the first-principles calculations. For a stable geometry, the lengths of TM-Sb bonds on the tube surface strongly depend on their relative electronegativity. In particular, we find that the intrinsic magnetic moment magnitude of the TM atom plays a decisive role in inducing tube magnetism, and only TM atoms with a larger intrinsic magnetic moment (≥3.0 µB) can induce the magnetism for tubes. The strong interaction and coupling between the TM d-orbital and Sb p-orbital lead to variously favorable magnetic phases, such as the spin bipolar semiconductor and half-semiconductor, which is predicted to be stable beyond room temperature. In addition, the weakening or quenching of the magnetism for the adsorbed TM atom is intimately related to the expansion of the TM atom valence electron configuration and the charge transfer. Furthermore, the TM adsorption can also effectively regulate the tube carrier mobility to the difference of several orders of magnitude, and results in significant carrier polarity and spin polarity of mobility. A sensitive electric-magnetic coupling effect was also shown to cause continuous magnetic phase transition, providing more opportunity for obtaining magneto-electric materials.

5.
J Phys Condens Matter ; 32(47): 475001, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32870810

RESUMO

Monolayer C2N has been successfully synthesized. To explore the enhancement of its stability and the expansion of its potential applications in electronics and optoelectronics, a vertical van der Waals heterostructure is constructed by C2N monolayer integrated with h-BN monolayer. The first-principles calculations based on the density functional theory show that this structure possesses a type-II band alignment with a smaller direct band gap and lager band offsets, suggesting that photo-generated electron-hole pairs can be well spatially separated, and thus an excellent photoelectric and photovoltaic material can be obtained. Also shown is that the electronic properties of such a heterostructure can be effectively regulated by a vertical strain and external electric field. For example, under compressive strain or forward electric field, its band gap can be significantly reduced to enhance light-excitation electron transition further, meanwhile the feature of direct band-gap and large band offsets is always well-preserved. Furthermore, it is found that the intrinsic heterostructure holds a wide optic adsorption range and large adsorption coefficient, and the applied compressive strain or a positive electric field can lead to a wide and high main absorption peak across the near-infrared, visible light, and ultraviolet region, implying that a tuned heterostructure has more promising applications in optoelectronics.

6.
Zhonghua Zhong Liu Za Zhi ; 42(8): 682-686, 2020 Aug 23.
Artigo em Chinês | MEDLINE | ID: mdl-32867462

RESUMO

Objective: To analyze the safety and short-term efficacy of breast-conserving surgery combined with intraoperative radiotherapy for early-stage breast cancer. Methods: A total of 101 consecutive patients who received breast-conserving surgery plus intraoperative radiotherapy were recruited to summarize the recent follow-up results and clinicopathological data. Univariate analysis and Logistic regression model were used to evaluate the factors affecting the postoperative adverse reactions and cosmetic effects. Results: Among 101 patients, 4 patients had recurrence or metastasis. The 3-years disease free survival rate was 94.9%, and the 3-years cumulative recurrence rate was 5.1%. Univariate analysis showed that the menstrual status and postoperative whole breast radiotherapy were associated with the postoperative adverse reactions (P<0.05). The T stage and applicator diameter were associated with the cosmetic effect (P<0.05). Multivariate analysis indicated that the diameter of the applicator (OR=3.701, P=0.026) and postoperative whole breast radiotherapy (OR=5.962, P=0.005) were independent factors for the postoperative adverse reactions, and the diameter of the applicator (OR=2.522, P=0.037) was an independent factor for the cosmetic effect. Conclusion: Breast-conserving surgery combined with intraoperative radiotherapy shows safety and good short-term efficacy in low-risk early-stage breast cancer.


Assuntos
Neoplasias da Mama/terapia , Mastectomia Segmentar , Radioterapia Adjuvante/métodos , Neoplasias da Mama/patologia , Terapia Combinada , Humanos , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Resultado do Tratamento
7.
Nanotechnology ; 31(31): 315206, 2020 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-32299069

RESUMO

Recently, the arsenic monolayer has been successfully fabricated by micromechanical stripping. However, it is a non-magnetic semiconductor, including its derivatives. Here, we theoretically explore how to induce magnetism for arsenene armchair nanotubes (AsANTs) with a low-concentration TM (TM = Co, Y, Rh, Ni, Mo, Ru) atom doping, especially focusing on their structural stability, magneto-electronic property, carrier mobility, and strain effects. The high stability of these doped tubes are confirmed by the calculated binding energy and formation energy, as well as Forcite annealing molecular dynamics simulations. The AsANT can act as bandgap narrowed non-magnetic semiconductors or highly spin-polarized magnetic semiconductors (half-semiconductor or bipolar magnetic semiconductor) depending on TM types, suggesting different promising applications such as developing infrared photodetectors with broadband detectionin or spintronic devices. The magnetic thermal stability beyond room temperature is predicted for doped tubes. Furthermore, the carrier mobility of AsANTs can be tuned into a wide region by TM doping, but it is enhanced in most cases. The carrier and spin polarity of mobility can also be clearly observed. Particularly, the applied strain can induce a rich magnetic phase transition among a half-semiconductor, half-metal, bipolar magnetic semiconductor and nonmagnetic state. Furthermore, the presented stepwise change of total magnetic moment between high magnetized and nonmagnetic states is highly desirable for engineering a mechanical switch which can reversibly work between magnetism and demagnetism to control spin-polarized transport by applying strain.

9.
J Phys Condens Matter ; 32(1): 015303, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31499486

RESUMO

The monolayer InSe has been successfully fabricated recently and studied intensely. Here, we investigate the geometrical stability and various physical properties such as electronic and magnetic feature, carrier mobility and strain effects for InSe nanoribbons. Our calculations show that armchair nanoribbons, regardless of the bare-edged or H-saturated ones, are semiconductors with an indirect bandgaps, but the bandgap size is increased greatly by H-saturation. Their electron mobility is predicted to be moderately large (from ~102 to ~103 cm2 V-1 s-1) with the holes being less mobile for wider ribbons, and the carrier polarity phenomenon becomes more prominently for H-saturation. The zigzag InSe nanoribbons are found to be magnetic metals with a bigger magnetic moment and the ferromagnetic ground state at the single edge. The magnetism stems from unpaired electrons at the In-rich edge. More interestingly, it is found that the externally applied mechanical strain can effectively tune the spin polarization efficiency at the Fermi level to two stepwise stages, suggesting that the strain can act as a tool for developing a mechanical switch to control spin-polarized transport under lower bias. The detailed analysis suggests that this strain-tuning mechanism can be attributed to the ionic and covalent bond-configuration competition due to the strain-induced bond-length alterations, which leads to the unpaired electron redistribution in magnetic atoms or vanishing.

10.
Zhonghua Liu Xing Bing Xue Za Zhi ; 40(9): 1089-1094, 2019 Sep 10.
Artigo em Chinês | MEDLINE | ID: mdl-31594151

RESUMO

Objective: To analyze the disease burden of stroke and its health loss attributable to passive smoking in people aged 60 years and over in Jiangsu province. Methods: Data were retrieved from the Chronic and Non-communicable Diseases and Risk Factors Surveillance in Jiangsu in 2013 and the death registry system in Jiangsu. Combined with the method in Global Burden of Disease Study 2016 (GBD2016), the indicators, such as population attributable fraction (PAF) and disability-adjusted life years (DALY) for stroke due to passive smoking were calculated. Results: In 2013, the mortality rate, age-standardized mortality rate, DALY and DALY rate of stroke in people aged 60 years and over in Jiangsu were 718.15/100 000, 439.28/100 000, 1 179 602 person years and 9 234.99/100 000, respectively. Year of life lost (YLL) accounted for 87.00% of the total DALY. The DALY and corresponding rate of stroke increased rapidly with age, and were higher in women (612 084 person years and 9 319.71/100 000, respectively) than those in men (567 518 person years and 9 145.33/100 000, respectively). The prevalence of passive smoking was 34.04% in people aged 60 years and over in Jiangsu. The PAF, attributable DALY, attributable DALY rate and its age- standardized rate of stroke due to passive smoking in people aged 60 years and over in Jiangsu were 3.88%, 45 769 person years, 358.12/100 000 and 920.64/100 000, respectively; and were also higher for men (4.35%, 24 687 person years, 397.82/100 000 and 515.30/100 000, respectively) than those for women (3.44%, 21 056 person years, 320.60/100 000, 405.34/100 000, respectively). Conclusions: The disease burden of stroke was heavy in the elderly in Jiangsu, and passive smoking might have great influence on the disease burden of stroke. Prevention and control of stroke and passive smoking exposure should be taken actively to improve health for the elderly.


Assuntos
Carga Global da Doença , Acidente Vascular Cerebral/epidemiologia , Poluição por Fumaça de Tabaco , Idoso , China/epidemiologia , Efeitos Psicossociais da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Anos de Vida Ajustados por Qualidade de Vida , Acidente Vascular Cerebral/economia
11.
Nanotechnology ; 30(48): 485703, 2019 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-31426048

RESUMO

Recently, a new type of quasi-1D graphene-like nanoribbons, periodically embedded with four- and eight- membered rings, has been successfully fabricated, and based on this structure, a novel planar 2D carbon allotrope, the so-called the net-Y, has been proposed. Here, we study various nanoribbons derived from such a 2D monolayer focusing on the structure stability, electronic, and transport properties, especially on the physical field coupling effects of electronic behaviors. Very high stability is predicted for various types of nanoribbons by the calculated binding energy and molecular dynamics simulation. Different edge shapes and widths have a significant influence on their electronic properties. Armchair nanoribbons are always semiconductors, and possess a high carrier mobility. After hydrogen termination, some metallic nanoribbons can become semiconductors or quasi-metals with massless Dirac-fermion behavior. In particular, the electronic properties of ribbons can be effectively modulated by applying strain and electric field. The band gap size and the transition from indirect to direct band gap can be realized upon strain or electric field. These flexibly tunable electronic properties for nanoribbons expand their applications in nanoelectronics and optoelectronics.

12.
Zhonghua Yu Fang Yi Xue Za Zhi ; 53(3): 267-271, 2019 Mar 06.
Artigo em Chinês | MEDLINE | ID: mdl-30841665

RESUMO

Objective: To analyze the attributable burden of smoking on the deaths of cardio-cerebral vascular diseases (CCVD) in inhabitants aged 30 years and above in Jiangsu Province. Methods: Comparative risk assessment approach in Global Burden of Disease (GBD) was used with the data from Jiangsu Non-communicable Disease and Behavioral Risk Factor Surveillance System and Death Monitoring Surveillance System in 2013, and population attributable fraction (PAF), years of life lost (YLL), work of potential years of life lost, index of life lost and life loss attributed to smoking were calculated. Results: In 2013, there were 162 158 CCVD deaths aged 30 years and above in the surveillance areas of Jiangsu Province, of which 25 102 deaths were attributed to smoking (PAF: 15.48%, attributed mortality rate: 55.13/100 000). The YLL, work of potential years of life lost and index of life lost were 532 494 person years, 78 024 person years and 9.15 years respectively. The decline of life expectancy was 0.58 years. The PAF of CCVD attributed to smoking in male and female were 27.97% and 3.18%, respectively, and the mortality rate of cardio-cerebral diseases attributed to smoking in male and female were 100.13/100 000 and 11.27/100 000, respectively. The burden of ischemic heart disease and hemorrhagic stroke were most severe, with standardized YLL rate were 3.65‰ and 3.20‰, respectively. Conclusion: Smoking caused a great burden of cardio-cerebral disease deaths in inhabitants in Jiangsu province.


Assuntos
Doenças Cardiovasculares/mortalidade , Transtornos Cerebrovasculares/mortalidade , Fumar/efeitos adversos , Adulto , Causas de Morte , China/epidemiologia , Feminino , Humanos , Masculino
13.
Zhonghua Yu Fang Yi Xue Za Zhi ; 53(2): 218-222, 2019 Feb 06.
Artigo em Chinês | MEDLINE | ID: mdl-30744300

RESUMO

Objective: To evaluate the risk of 10-year risk of ischemic cardiovascular disease (ICVD) in patients with type 2 diabetes aged 35 years old and above in two cities of Jiangsu province. Methods: From December 2013 to January 2014, a total of 15 624 patients with type 2 diabetes aged 35 years old and above, who received national basic public health service in Changshu county of Suzhou city, Huai'an and Qinghe districts of Huai'an city, Jiangsu province, were recruited by cluster sampling method. Face-to-face questionnaire survey, anthropometric and laboratory measurements were conducted to collect exposures to ICVD risk factors. Improved Ten Year Risk Assessment Table of ICVD in Chinese was used to assess the risk score and the absolute risk of developing ICVD. Results: The participants were (62.2±9.7) years old, of which 6 137 were men (39.3%). Among the participants, the highest rate of exposure to ICVD risk factors was high systolic blood pressure (74.8%, n=11 685), followed by high total cholesterol (70.7%, n= 11 051).The score of 10-year risk for ICVD was (10.4±3.3) and the median (P(25)-P(75)) value of absolute risk was 15.6% (6.8%-32.7%). 16.7% (n=2 602) participants were under extremely high risk of 10-year risk for ICVD, 23.8% (n=3 714) under high-risk and 24.0% (n=3 746) under middle-risk. Among the total risk score of ICVD, age (49.1%), hypertension (17.7%) and diabetes (15.5%) accounted for relatively high proportion, however, smoking (11.0%) was the most important risk factor except for age (47.4%) and systolic blood pressure (20.5%) in male participants. Conclusion: Patients with type 2 diabetes aged 35 years old and above in two cities of Jiangsu Province have a high risk of developing ICVD for 10 years, especially in elderly, female, hypertension patients and male smokers.


Assuntos
Diabetes Mellitus Tipo 2/epidemiologia , Isquemia Miocárdica/epidemiologia , Adulto , Idoso , China/epidemiologia , Cidades , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
14.
J Phys Condens Matter ; 31(14): 145301, 2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30645986

RESUMO

Mono-layered h-BN and its derivatives are very important low-dimensional materials, which have been widely investigated so far. Here, we theoretically study the structural stability and magneto-electronic properties of oxygen (O) terminated zigzag-edged h-BN nanoribbons, especially focusing on strain tuning effects. The O dimerization at the B edge of the ribbon enhances the system stability greatly. A Poisson ratio of 0.2 and bearing a strain more than 20% can be reached. In the absence of strain, the O-terminated ribbon is a magnetic metal. However, the rich magnetic phase transitions among the non-magnetic metal, a spin gapless semiconductor, and a wide-gap half-metal can be realized continuously by applying strain in the ferromagnetic state. Thus, based on such a material feature, we can design a magnetic switch device which can work between the magnetic and non-magnetic states by strain modification. Also shown is that the magnetism stability can be enhanced to the level at room temperature upon strain, and the massless Dirac-fermion behavior for the ß-spin state can be clearly detected in the spin gapless semiconductor phase under appropriate strains.

15.
Phys Chem Chem Phys ; 21(4): 1830-1840, 2019 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-30629061

RESUMO

Functionalizing graphene to develop on-demand nanodevices is highly desirable, but still remains challenging. Here, we theoretically propose the functionalization of armchair graphene nanoribbons by low-concentration metal (M) atom (M = Ti, Ni, Sn, or Hg) doping and investigate the structural stability and electronic behaviors of these doped systems in depth. The calculated binding energy and formation energy as well as the molecular dynamics simulation show that the geometries of these hybridized ribbons are rather stable. With metal doping, the ribbons present rich and flexibly tunable bandgaps, depending on the metal atom and doping position, which can be attributed to newly emerged hybridized subbands near the Fermi level and the entire energy band structure shifting upward due to the increased electron number in the ribbon donated from the dopant. These bandgaps can also be further tuned substantially by the stress. And the carrier mobility is calculated based on the deformation potential theory, which shows that the different metal doping can effectively control the carrier mobility, and a large carrier polarity can also be clearly observed. Furthermore, the metal doping can significantly enhance the device properties of the ribbon as compared with those of the pristine ribbon, such as creating a large negative differential resistance phenomenon. These studies demonstrate that these doping systems might hold promising applications in nano-electronics.

16.
Nanotechnology ; 30(14): 145201, 2019 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-30593010

RESUMO

Phosphorene and its derivatives so far have attracted substantial research interest due to its promising properties for developing nanoscale electronic devices. Here, we present a theoretical investigation on the functionalized features, such as the improved electronic structure and carrier mobility, for armchair-edged single walled black phosphorus nanotubes (PNTs) with the substitutional doping of low-concentration transition-metal atoms (Ti, Mn, Fe, and Ni). They are predicted to be exceptional magnetic semiconductors (MSCs), such as half-semiconductor or bipolar MSC. Their spin-resolved carrier mobility at room temperature holds doping element- dependence as well as carrier and spin polarity. Particularly, the difference by two orders of magnitude for carrier mobility emerges due to different TM doping. More interestingly, the carrier mobility in armchair PNTs serving as the channel material of a spin field effect transistor is predicted to be modified strongly by a gate voltage. The enhanced carrier mobility and its gate voltage direction-dependent behavior, as well as the more obvious carrier and spin polarity of mobility, can be observed clearly under gate voltage, which further facilitates the separation of different carriers and spin states and also suggests that realistic carrier mobility is gate voltage-dependent in a field effect transistor.

17.
Zhonghua Liu Xing Bing Xue Za Zhi ; 39(12): 1596-1601, 2018 Dec 10.
Artigo em Chinês | MEDLINE | ID: mdl-30572384

RESUMO

Objective: To quantify the burden of cardiovascular disease (CVD) deaths that attributed to metabolic disorders in population aged ≥25 years in Jiangsu province. Methods: The data we used were from the following three sources: 1) 2015 Jiangsu Chronic Disease Risk Factor and Nutrition Survey, 2) death surveillance, 3) results of the 2016 Global Burden of Disease Study, based on population attributable fractions (PAF), to analyze related parameters as mortality, years of life lost (YLL), life expectancy (LE) and premature mortality. Results: Most people died from ischemic stroke (IS) showed the standard mortality as 87.48/100 000. High SBP appeared as the major cause on CVD deaths. PAF with high cholesterol and high BMI decreased along with the increase of age while high fasting plasma glucose increased. Deaths due to ischemic heart diseases, IS or hemorrhagic stroke that attributed to metabolism disorders would reduce the LE by 1.08, 1.07 or 0.55 years, respectively. Males appeared to have higher YLL than females and were more likely to die from premature CVD, as the consequence of having metabolism disorders. Conclusions: Blood pressure control should be considered an important approach to reduce the burden of CVD. According to the characteristics of gender-related risks and the distinct impact of age-related metabolism disorders on different CVD diseases, stratified strategies should be strengthened for comprehensive prevention and control of CVD, in Jiangsu province.


Assuntos
Doenças Cardiovasculares/epidemiologia , Efeitos Psicossociais da Doença , Expectativa de Vida , Doenças Metabólicas/epidemiologia , Mortalidade/tendências , Adulto , Pressão Sanguínea , Doença Crônica , Feminino , Humanos , Masculino , Mortalidade Prematura , Fatores de Risco
18.
J Phys Condens Matter ; 30(44): 445802, 2018 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-30132442

RESUMO

Magnetic nanomaterials with the desirable nature are the basis for developing future spintronic devices, and research for them is of fundamental interest. Here, we explore the realization of half-metallicity and magnetic phase transition for phagraphene nanoribbons in virtue of functional groups (OH and CN) with different coverage fractions and external electric fields. The first-principles calculations show that a single-edge CN functionalization only makes a intrinsic spin-degenerate semiconducting ribbon converted to a quasi-metal or metal, while a single-edge OH modification leads to an occurrence of the half-semiconducting nature regardless of the coverage fraction of groups. Interestingly, the half-metal behavior for the CN and OH double-edge modified ribbons can be achieved either in the zero-electric-field intrinsic state for most of functionalized systems or at a very low electric field, 0.1 V Å-1. More importantly, the observed critical electric field for the transition from ferromagnetic to nonmagnetic phase is lowered significantly almost for all systems, this benefits to design a low electric-field-controlling magnetic switch which can reversibly work between both magnetic and nonmagnetic states. The calculated Gibbs free energy confirms that the group-modified ribbons generally hold a more favorable energy stability in most of the cases, facilitating likely experimental realization.

19.
Eur Rev Med Pharmacol Sci ; 22(11): 3502-3514, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29917205

RESUMO

OBJECTIVE: Dipeptidyl peptidase-4 (DPP-4) inhibitors are a new class of oral antidiabetic agents for type 2 diabetes mellitus (T2DM) patients. However, the effects and safety of DPP-4 inhibitors in T2DM patients with renal impairment (RI) remain controversial. Therefore, we conducted this meta-analysis to assess the efficacy and safety of DPP-4 inhibitors in T2DM patients with moderate to severe RI. MATERIALS AND METHODS: The PubMed, Embase, and Web of Science database were searched for published randomized controlled trials (RCTs), which compared DPP-4 inhibitors with placebo or a control regimen. A fixed-model effect or random-effect model was used to assess the effects of DPP-4 inhibitors on T2DM patients with RI. Subgroup analysis or meta-regression analysis were performed to explore the potential sources of heterogeneity among the included studies. RESULTS: 13 RCTs with a total of 2,940 patients were included in this meta-analysis. Compared with other treatments, DPP-4 inhibitors were associated with a greater change in HbA1c level (weight mean difference (WMD)=-0.50, 95%CI: -0.61, -0.39; p<0.001), and a higher response rate of patients achieving the HbA1c goal of <7% (risk ratio (RR)=1.38, 95%CI: 1.12, 1.70; p=0.002). Subgroup analysis suggested that the reduced HbA1c was observed in all types of DPP-4 inhibitors, and in patients with moderate or severe RI, but not in those with end-stage renal disease. DPP-4 inhibitors did not significantly lower the FPG level (WMD=-0.36, 95%CI: -0.92, 0.20; p=0.204), and this was seen in all types of DPP-4 inhibitors except gemigliptin, which showed a significant reduction in FPG level. The prevalence of adverse events (RR=0.98, 95%CI: 0.94, 1.02; p=0.256) in the two groups was not significantly different, and DPP-4 inhibitors did not induce a higher rate of hypoglycemia (RR=1.31, 95%CI: 0.97, 1.77; p=0.075). CONCLUSIONS: DPP-4 inhibitors significantly lowered HbA1c levels in T2DM patients with moderate to severe RI. And the treatment of DPP-4 inhibitors did not increase the risk of hypoglycemia and adverse events. Considering the potential limitations in this meta-analysis, more large-scale, well-conducted RCTs are needed to identify our findings.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Inibidores da Dipeptidil Peptidase IV/uso terapêutico , Bases de Dados Factuais , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/patologia , Inibidores da Dipeptidil Peptidase IV/efeitos adversos , Hemoglobinas Glicadas/análise , Humanos , Hipoglicemia/complicações , Hipoglicemia/diagnóstico , Insuficiência Renal/complicações , Insuficiência Renal/patologia , Risco , Índice de Gravidade de Doença , Resultado do Tratamento
20.
Phys Chem Chem Phys ; 20(19): 13574-13579, 2018 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-29736547

RESUMO

One-dimensional phosphorus nanotubes (PNTs) are important derivatives of phosphorene. Herein, the magneto-electronic properties for PNTs doped with low-concentration transition metals (TM) (Fe, Co, and Ni) both in their inner and outer layers were investigated in detail. TM-PNTs are very stable with high structural integrity and versatile magnetic properties. In particular, some important magnetic properties such as half-metallic and dilute magnetic semiconducting behaviors can be observed, which are the basis of the application of TM-PNTs in spintronics. Furthermore, the electric field can induce magnetic phase transitions and demagnetization can occur under a very low electric field due to Co-doping in the outer layer of the PNTs. This interesting feature is very attractive for constructing electric-field-controllable magnetic/nonmagnetic switch devices that are operated in two possible states.

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