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1.
World J Diabetes ; 15(4): 638-644, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38680701

RESUMEN

BACKGROUND: Age is a significant risk factor of diabetes mellitus (DM). With the develop of population aging, the incidence of DM remains increasing. Understanding the epidemiology of DM among elderly individuals in a certain area contributes to the DM interventions for the local elderly individuals with high risk of DM. AIM: To explore the prevalence of DM among elderly individuals in the Lugu community and analyze the related risk factors to provide a valid scientific basis for the health management of elderly individuals. METHODS: A total of 4816 elderly people who came to the community for physical examination were retrospectively analyzed. The prevalence of DM among the elderly was calculated. The individuals were divided into a DM group and a non-DM group according to the diagnosis of DM to compare the differences in diastolic blood pressure (DBP) and systolic blood pressure (SBP), fasting blood glucose, body mass index (BMI), waist-to-hip ratio (WHR) and incidence of hypertension (HT), coronary heart disease (CHD), and chronic kidney disease (CKD). RESULTS: DM was diagnosed in 32.70% of the 4816 elderly people. The BMI of the DM group (25.16 ± 3.35) was greater than that of the non-DM group (24.61 ± 3.78). The WHR was 0.90 ± 0.04 in the non-DM group and 0.90 ± 0.03 in the DM group, with no significant difference. The left SBP and SBP in the DM group were 137.9 mmHg ± 11.92 mmHg and 69.95 mmHg ± 7.75 mmHg, respectively, while they were 126.6 mmHg ± 12.44 mmHg and 71.15 mmHg ± 12.55 mmHg, respectively, in the non-DM group. These findings indicate higher SBP and lower DBP in DM patients than in those without DM. In the DM group, 1274 patients were diagnosed with HT, accounting for 80.89%. Among the 3241 non-DM patients, 1743 (53.78%) were hypertensive and 1498 (46.22%) were nonhypertensive. The DM group had more cases of HT than did the non-DM group. There were more patients with CHD or CKD in the DM group than in the non-DM group. There were more patients who drank alcohol more frequently (≥ 3 times) in the DM group than in the non-DM group. CONCLUSION: Older adults in the Lugu community are at a greater risk of DM. In elderly individuals, DM is closely related to high BMI and HT, CHD, and CKD. Physical examinations should be actively carried out for elderly people to determine their BMI, SBP, DBP, and other signs, and sufficient attention should be given to abnormalities in the above signs before further diagnosis.

2.
Biosens Bioelectron ; 171: 112729, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33113387

RESUMEN

A novel chemiluminescence (CL) imaging platform was constructed for prostate specific antigen (PSA) detection in a multiple signal amplifying manner. To construct the platform, the primary antibody for PSA was firstly immobilized on a O-ring area of a glass slide for recognizing the PSA. The horseradish peroxidase (HRP) and the secondary antibody of PSA (Ab2) functionalized Au NPs (HRP-Au NPs-Ab2) were modified on the platform through immunoreaction between PSA and Ab2. The excellent catalytic effect of Au NPs and HRP on the HRP-Au NPs-Ab2 to the luminol-H2O2 CL system provided the dual-signal amplification for PSA detection. To further enhance the sensitivity, tyramine signal amplification (TSA) strategy was introduced: tyramine-HRP conjugates were added into the O-ring reservoir and thus tyramine-HRP repeats formed in the presence of H2O2, generating a multiple signal amplification because of the large amounts of HRP on the sensing interface. The excellent performance of HRP-Au NPs-Ab2 and TSA strategy endows the CL platform with high sensitivity. The PSA was detected with a photomultiplier tube (PMT) and visually analyzed by a charge coupled device (CCD), respectively. The linear ranges of PMT and CCD for PSA are 0.1-100.0 ng mL-1 with a detection limit of 0.05 pg mL-1 and 0.5 - 100.0 ng mL-1 with a detection limit of 0.1 pg mL-1, respectively. The levels of PSA in several human serum samples were determined and the recoveries are ranged from 82.5% - 117.0%. This CL immunosensing platform holds great potential for bioactive molecules detection visually and sensitively.


Asunto(s)
Técnicas Biosensibles , Nanopartículas del Metal , Técnicas Electroquímicas , Oro , Humanos , Peróxido de Hidrógeno , Inmunoensayo , Límite de Detección , Luminiscencia , Masculino , Antígeno Prostático Específico
3.
Adv Mater ; 30(49): e1804644, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30284321

RESUMEN

Optical characteristics of luminescent materials, including emission color (wavelength), lifetime, and excitation mode, play crucial roles in data communication and information security. Conventional luminescent materials generally display unicolor, unitemporal, and unimodal (occasionally bimodal) emission, resulting in low-level readout and decoding. The development of multicolor, multitemporal, and multimodal luminescence in a single material has long been considered to be a significant challenge. In this study, for the first time, the superior integration of colorful (red-orange-yellow-green), bitemporal (fluorescent and delayed), and four-modal (thermo-/mechano-motivated and upconverted/downshifted) emissions in a particular piezoelectric particle via optical multiplexing of dual-lanthanide dopants is demonstrated. The as-prepared versatile NaNbO3 :Pr3+ ,Er3+ luminescent microparticles shown are particularly suitable for embedding into polymer films to achieve waterproof, flexible/wearable and highly stretchable features, and synchronously to provide multidimensional codes that can be visually read-out using simple and commonly available tools (including the LED of a smartphone, pen writing, cooling-heating stimuli, and ultraviolet/near-infrared lamps). These findings offer unique insight for designing highly integrated stimuli-responsive luminophors and smart devices toward a wide variety of applications, particularly advanced anticounterfeiting technology.

4.
Int J Surg ; 56: 1-6, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29886280

RESUMEN

The epidemiological trend in liver diseases becomes more serious worldwide. Several recent articles published by International Journal of Surgery in 2018 particularly emphasized the encouraging clinical benefits of hepatectomy, liver regeneration and liver transplantation, however, there are still many technical bottlenecks underlying these therapeutic approaches. Remarkably, a few preliminary studies have shown some clues to the role of three-dimensional (3D) printing in improving traditional therapy for liver diseases. Here, we concisely elucidated the curative applications of 3D-printing (no cells) and 3D Bio-printing (with hepatic cells), such as 3D-printed patient-specific liver models and devices for medical education, surgical simulation, hepatectomy and liver transplantation, 3D Bio-printed hepatic constructs for liver regeneration and artificial liver, 3D-printed liver tissues for evaluating drug's hepatotoxicity, and so on. Briefly, 3D-printed liver models and bioactive tissues may facilitate a lot of key steps to cure liver disorders, predictably bringing promising clinical benefits. This work further provides novel insights into facilitating treatment of hepatic carcinoma, promoting liver regeneration both in vivo and in vitro, expanding transplantable liver resources, maximizing therapeutic efficacy as well as minimizing surgical complications, medical hepatotoxicity, operational time, economic costs, etc.


Asunto(s)
Hepatopatías/terapia , Hígado/fisiopatología , Impresión Tridimensional , Educación Médica/métodos , Hepatectomía/métodos , Humanos , Hepatopatías/diagnóstico , Regeneración Hepática , Trasplante de Hígado/métodos , Modelos Biológicos
5.
Biosens Bioelectron ; 99: 92-98, 2018 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-28743084

RESUMEN

A novel and competitive electrochemiluminescence (ECL) aptasensor for prostate specific antigen (PSA) assay was constructed using gold nanorods functionalized graphene oxide (GO@AuNRs) multilabeled with glucose oxidase (GOD) and streptavidin (SA) toward luminol-based ECL system. A strong initial ECL signal was achieved by electrodeposited gold (DpAu) on the electrode because of gold nanoparticles (AuNPs) motivating the luminol ECL signal. The signal probes prepared by loading GOD and SA-biotin-DNA on GO@AuNRs were used for achieving multiple signal amplification. In the absence of PSA, the signal probes can be attached on the electrode by hybridization reaction between PSA aptamer and biotin-DNA. In this state, the GOD loaded on the probe could catalyze glucose to in situ produce H2O2 and then AuNRs catalyze H2O2 to generate abundant reactive oxygen species (ROSs) in luminol ECL reaction. Both the high-content GOD and AuNRs in the signal probe amplified the ECL signal in the ECL system. Moreover, the combination of SA with biotin-DNA further expands ECL intensity. The integration of such amplifying effects in this protocol endows the aptasensor with high sensitivity and good selectivity for PSA detection. This aptasensor exhibits a linear relation in the range of 0.5pgmL-1 to 5.0ngmL-1 with the detection limit of 0.17pgmL-1 (S/N = 3). Besides, the strategy was successfully applied in determination of human serum samples with recovery of 81.4-116.0%.


Asunto(s)
Técnicas Biosensibles , Glucosa Oxidasa/química , Nanopartículas del Metal/química , Antígeno Prostático Específico/aislamiento & purificación , Aptámeros de Nucleótidos/química , Biotina/química , Oro/química , Grafito/química , Humanos , Peróxido de Hidrógeno/química , Límite de Detección , Nanotubos/química , Antígeno Prostático Específico/sangre , Estreptavidina/química
6.
J Phys Chem A ; 121(34): 6388-6397, 2017 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-28686439

RESUMEN

The optical absorption spectra of Si2-Si33 clusters were systematically studied by a time-dependent density functional theory approach. The calculations revealed that the absorption spectrum becomes significantly broad with increasing cluster size, stretching from ultraviolet to the infrared region. The absorption spectra are closely related to the structural motifs. With increasing cluster size, the absorption intensity of cage structures gradually increases, but the absorption curves of the prolate and the Y-shaped structures are very sensitive to cluster size. If the transition energy reaches ∼12 eV, it is noted that all the clusters have remarkable absorption in deep ultraviolet region of 100-200 nm, and the maximum absorption intensity is ∼100 times that in the visible region. Further, the optical responses to doping in the Si clusters were studied.

7.
Phys Chem Chem Phys ; 17(41): 27734-41, 2015 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-26435173

RESUMEN

We performed first-principles calculations to study the structural stability of Si78 clusters with or without hydrogen passivation. The calculations reveal that an endohedral double cage isomer is more stable than the diamond-like structure, whereas the opposite is found for the hydrogen passivated isomers. In particular, the hydrogenated double cage and diamond-like structure may display blue shifts to the visible and UV regions, respectively. The IR vibration spectra, ionization potential (IP) and electronic density-of-states of the clusters were calculated and discussed.

8.
Nanoscale ; 7(34): 14444-51, 2015 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-26252942

RESUMEN

The structures and optical properties of silicon nanoclusters (Si NCs) have attracted continuous interest in the last few decades. However, it is a great challenge to determine the structures of Si NCs for accurate property calculation due to the complication and competition of various structural motifs. In this work, a Si172 NC with a size of about 1.8 nm was investigated using a genetic algorithm combined with tight-binding and DFT calculations. We found that a diamond crystalline core with 50 atoms (1.2 nm) was formed in the Si172 NC. It can be expected that at a size of about 172 atoms, a diamond crystalline structure can nucleate from the center of the Si NCs. The optical properties of the pure and hydrogenated Si172 NC structures also have been studied using the TDDFT method. Compared with the pure Si172 NC, the absorption peaks of the hydrogenated Si172 NC are obviously blue-shifted.

9.
J Phys Chem A ; 117(13): 2672-7, 2013 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-23373572

RESUMEN

The structures and electronic properties of the SiAu(n) (n = 17-20) clusters are systematically investigated using DFT calculations. The result shows that doping with silicon would significantly change the structures of the gold clusters. For the SiAu(n) (n = 17-20) clusters, the lowest-energy structures exhibit shell-like cage configuration in which the dopant Si atom binds to the cage surface and one Au atom skips to the top of the Si atom forming a SiAu5 or SiAu6 subunit except SiAu19, which is a tetrahedron-like structure with a protruding Au atom. The Au atoms of the SiAu(n) (n = 17-20) clusters carry different partial charges due to their different locations.

10.
Eur J Med Chem ; 46(10): 4970-9, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21871694

RESUMEN

A series of dual binding site acetylcholinesterase (AChE) inhibitors have been designed, synthesized, and tested for their ability to inhibit AChE, butyrylcholinesterase (BChE), AChE-induced and self-induced ß-amyloid (Aß) aggregation. The new hybrids consist of a unit of 1-azabenzanthrone and a tacrine or its congener, connected through an oligomethylene linker containing an amine group at variable position. These hybrids exhibit high AChE inhibitory activity with IC(50) values in the nanomolar range in most cases. Moreover, five out of the 12 hybrids of this series, particularly those bearing a tetrahydroacridine moiety, exhibit a significant in vitro inhibitory activity toward the AChE-induced and self-induced Aß aggregation, which makes them promising anti-Alzheimer drug candidates.


Asunto(s)
Péptidos beta-Amiloides/metabolismo , Aporfinas/química , Aporfinas/farmacología , Inhibidores de la Colinesterasa/química , Inhibidores de la Colinesterasa/farmacología , Acetilcolinesterasa/metabolismo , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/enzimología , Enfermedad de Alzheimer/metabolismo , Amiloide/metabolismo , Animales , Aporfinas/síntesis química , Aporfinas/farmacocinética , Barrera Hematoencefálica/metabolismo , Butirilcolinesterasa/metabolismo , Inhibidores de la Colinesterasa/síntesis química , Inhibidores de la Colinesterasa/farmacocinética , Electrophorus , Caballos , Humanos , Modelos Biológicos , Tacrina
11.
J Phys Condens Matter ; 23(20): 205305, 2011 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-21540510

RESUMEN

Binary C(7)Si(n) (n = 1-7) clusters are studied using density functional calculations at the level of B3LYP/6-311G(d). Lowest-energy structures have been determined theoretically and their properties such as binding energies, second differences in energy and highest-occupied and lowest-unoccupied molecular orbital gaps have been analyzed. It is found that the lowest-energy structures of the C(7)Si(n) (n = 1-7) clusters change from linear to planar when n ≥ 3, and in the planar structures C atoms prefer to form five- and six-membered rings surrounded by extra Si atoms in the form of the C(2)Si units.

12.
J Comput Chem ; 32(7): 1271-8, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21425284

RESUMEN

We performed first-principles calculations to study the structure and stability of Si(70) cluster. The results from the density functional theory calculation with the Becke-Lee-Yang-Parr and B3LYP exchange-correlation functionals suggest that a diamond-like Si(70) isomer is the most stable structure, in contrast to endohedral fullerenes of Si(70). On the other hand, an endohedral fullerene of Si(16)@Si(54) was found to be slightly lower in energy than the diamond-like Si(70) if the Predew-Burke-Ernzerhof functional is used. Our calculation results suggest that around n = 70, the endohedral fullerene and diamond-like isomer are expected to be competitive. The calculated IR vibration spectra, ionization potential, and inverse mobilities were also calculated and discussed.


Asunto(s)
Teoría Cuántica , Silicio/química , Modelos Moleculares , Estructura Molecular
14.
Phys Chem Chem Phys ; 12(30): 8551-6, 2010 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-20552120

RESUMEN

Using a genetic algorithm method to search for low-energy structures, we studied the evolution of structural motifs in Si, Ge, and Al clusters. We were able to observe how bulk-like structural motifs occur in these clusters as the size of the system increases, replacing structural motifs characteristic of clusters at smaller sizes. Si and Ge clusters adopt prolate structures at small sizes. While Si clusters switch to a spherical motif around the size of 30 atoms, Ge clusters exhibit plate-like motifs at the size of 40-atom clusters before transforming into more spherical shapes. For Al clusters, an ordered layered structural motif begins to appear at a relatively small cluster size around 25-27 atoms.

15.
J Chem Phys ; 132(21): 214509, 2010 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-20528033

RESUMEN

The structures of Ge(n) (n=34-39) clusters were searched by a genetic algorithm using a tight-binding interatomic potential. First-principles calculations based on density functional theory were performed to further identify the lowest-energy structures. The calculated results show that Ge(n) (n=34-39) clusters favor prolate or Y-shaped three-arm structures consisting of two or three small stable clusters (Ge(6), Ge(7), Ge(9), or Ge(10)) linked by a Ge(6) or Ge(9) bulk unit. The calculated results suggest the transition point from prolate to Y-shaped three-arm structures appears at Ge(35) or Ge(36).

16.
J Chem Phys ; 131(12): 124507, 2009 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-19791894

RESUMEN

The structures of Ge(n) (n=40-44) clusters were searched by genetic algorithm combined with a tight-binding method. First-principles calculations based on density functional theory were performed to further optimize the isomer structures. The calculated results show that Ge(n) (n=40-44) clusters favor platelike structures, consisted of four small magic clusters (Ge(9) or Ge(10)), and a Ge(4) core. The Ge(4) core along with the parts of the four linked small clusters forms a diamond segment. The cluster mobilities of the most stable structures are in good agreement with the experimental data.

17.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 6): m613, 2009 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-21582984

RESUMEN

In the title compound, [Zn(2)Cl(4)(C(22)H(18)N(4))(2)]·2C(3)H(7)NO, the 1,3-bis-[(benzimidazol-1-yl)meth-yl]benzene ligand bridges two ZnCl(2) units, forming a centrosymmetric dinuclear mol-ecule. The Zn(II) atom shows a distorted tetra-hedral coordination within a Cl(2)N(2) donor set.

18.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 6): m629, 2009 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-21582997

RESUMEN

The title compound, {[Cd(C(4)H(4)O(6))]·0.167H(2)O}(n), adopts a three-dimensional network structure in which each Cd(II) ion is chelated by two pairs of carboxyl-ate and hydroxyl O atoms from two tartrate anions, and is additionally linked to two O atoms of two carboxyl-ate groups that are not involved in chelation. The asymmetric unit has four independent cadmium atoms, two of which lie on special positions of 2 site symmetry. The tartrate anions all lie on general positions. All hydroxyl groups are engaged in O-H⋯O hydrogen-bonds, one of which is also bifurcated. The non-coordinating water molecule is situated on a site with half-occupation.

19.
J Phys Condens Matter ; 21(45): 455501, 2009 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-21694013

RESUMEN

The structures of Si(n) (n = 2-33) were confirmed by genetic algorithm (GA)/tight binding (TB) search and ab initio calculations at the B3LYP/6- 311++G(2d) and PW91/6-311++G(2d) level, respectively. The fragmentation energies, binding energies, second differences in energy, and highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbital (LUMO) gaps in the size range 2≤n≤33 were calculated and analyzed systematically. We extended the cluster size involved in the fragmentation analyses up to Si(33), and studied the multi-step fragmentations of Si(n). The calculated result is similar to the fragmentation behavior of small silicon clusters studied previously, showing that Si(6), Si(7), and Si(10) have relatively larger stabilities and appear more frequently in the fragmentation products of large silicon clusters, which is in good agreement with the experimental observations.

20.
J Phys Chem A ; 112(26): 5815-23, 2008 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-18533643

RESUMEN

We performed an unbiased search for low-energy structures of medium-sized neutral Si n and Ge n clusters ( n = 25-33) using a genetic algorithm (GA) coupled with tight-binding interatomic potentials. Structural candidates obtained from our GA search were further optimized by first-principles calculations using density functional theory (DFT). Our approach reproduces well the lowest-energy structures of Si n and Ge n clusters of n = 25-29 compared to previous studies, showing the accuracy and reliability of our approach. In the present study, we pay more attention to determine low-lying isomers of Si n and Ge n ( n = 29-33) and study the growth patterns of these clusters. The B3LYP calculations suggest that the growth pattern of Si n ( n = 25-33) clusters undergoes a transition from prolate to cage at n = 31, while this transition appears at n = 26 from the PBE-calculated results. In the size range of 25-33, the corresponding Ge n clusters hold the prolate growth pattern. The relative stabilities and different structural motifs of Si n and Ge n ( n = 25-33) clusters were studied, and the changes of small cluster structures, when acting as building blocks of large clusters, were also discussed.

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