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1.
Zhonghua Xin Xue Guan Bing Za Zhi ; 51(5): 490-496, 2023 May 24.
Artículo en Chino | MEDLINE | ID: mdl-37198120

RESUMEN

Objective: To explore the safety and efficacy of excimer laser coronary angioplasty (ELCA) for the treatment of degenerated great saphenous vein graft (SVG). Methods: This is a single-center, prospective, single-arm study. Patients, who were admitted to the Geriatric Cardiovascular Center of Beijing Anzhen Hospital from January 2022 to June 2022, were consecutively enrolled. Inclusion criteria were recurrent chest pain after coronary artery bypass surgery (CABG), and coronary angiography confirmed that the SVG stenosis was more than 70% but not completely occluded, and interventional treatment for SVG lesions was planned. Before balloon dilation and stent placement, ELCA was used to pretreat the lesions. Optical coherence tomography (OCT) examination was performed and postoperative index of microcirculation resistance (IMR) were assessed after stent implantation. The technique success rate and operation success rate were calculated. The technique success was defined as the successful passage of the ELCA system through the lesion. Operation success was defined as the successful placement of a stent at the lesion. The primary evaluation index of the study was IMR immediately after PCI. Secondary evaluation indexes included thrombolysis in myocardial infarction (TIMI) flow grade, corrected TIMI frame count (cTFC), minimal stent area and stent expansion measured by OCT after PCI, and procedural complications (Ⅳa myocardial infarction, no reflow, perforation). Results: A total of 19 patients aged (66.0±5.6) years were enrolled, including 18 males (94.7%). The age of SVG was 8 (6, 11) years. The length of the lesions was greater than 20 mm, and they were all SVG body lesions. The median stenosis degree was 95% (80%, 99%), and the length of the implanted stent was (41.7±16.3)mm. The operation time was 119 (101, 166) minutes, and the cumulative dose was 2 089 (1 378, 3 011)mGy. The diameter of the laser catheter was 1.4 mm, the maximum energy was 60 mJ, and the maximum frequency was 40 Hz. The technique success and the operation success rate were both 100% (19/19). The IMR after stent implantation was 29.22±5.95. The TIMI flow grade of patients after ELCA and stent implantation was significantly improved (all P>0.05), and the TIMI flow grade of all patients after stent implantation was Grade Ⅲ. The cTFC decreased significantly after ELCA (33.2±7.8) and after stent placement (22.8±7.1) than preoperative level (49.7±13.0) (both P<0.001). The minimum stent area was (5.53±1.36)mm2, and the stent expansion rate was (90.0±4.3)%. Perforation, no reflow, type Ⅳa myocardial infarction and other complications were not observed. However, postoperative high-sensitivity troponin level was significantly increased ((67.937±33.839)ng/L vs. (5.316±3.105)ng/L, P<0.001). Conclusion: ELCA is safe and effective in the treatment of SVG lesions and could improve microcirculation and ensure full expansion of stent.


Asunto(s)
Aterectomía Coronaria , Infarto del Miocardio , Intervención Coronaria Percutánea , Masculino , Humanos , Anciano , Estudios Prospectivos , Láseres de Excímeros/uso terapéutico , Vena Safena/trasplante , Constricción Patológica , Aterectomía Coronaria/métodos , Angiografía Coronaria , Stents , Resultado del Tratamiento
2.
Zhonghua Liu Xing Bing Xue Za Zhi ; 44(5): 689-693, 2023 May 10.
Artículo en Chino | MEDLINE | ID: mdl-37221054

RESUMEN

A crucial lesson gained through the pandemic preparedness and response to COVID-19 is that all measures for epidemic control must be law-based. The legal system is related not only to public health emergency management per se but also to all aspects of the institutional supporting system throughout the lifecycle. Based on the lifecycle emergency management model, this article analyses the problems of the current legal system and the potential solutions. It is suggested that the lifecycle emergency management model shall be followed to establish a more comprehensive public health legal system and to gather the intelligence and consensus of experts with different expertise, including epidemiologists, sociologists, economists, jurist and others, which will collaboratively promote the science-based legislation in the field of epidemic preparedness and response for the establishment of a comprehensive legal system for public health emergency management and with Chinese characteristics.


Asunto(s)
Planificación en Desastres , Salud Pública , Humanos , China , Pandemias/prevención & control , Urgencias Médicas
3.
Zhonghua Yan Ke Za Zhi ; 58(12): 1033-1038, 2022 Dec 11.
Artículo en Chino | MEDLINE | ID: mdl-36480884

RESUMEN

Objective: To evaluate the relationship between lesion features of cytomegalovirus (CMV) retinitis, including lesion size and degree of opacity of lesion borders, and aqueous CMV-DNA load in patients after allogeneic hematopoietic stem cell transplantation. Methods: It was a retrospective case series study. Data of patients diagnosed as CMV retinitis after allogeneic hematopoietic stem cell transplantation at the Department of Ophthalmology, Peking University Third Hospital from January 2018 to October 2020 were reviewed. Lesion size was detected by ultra-wide-field fundus image and measured by ImageJ, an image processing and analysis software. Opacity of lesion borders was evaluated by a masked reader. The CMV retinitis lesions were divided into 3 types according to the opacity degree of the border of the lesions: suspected active lesion mildly to moderately opacified lesion and severely opacified lesion. All eyes were diagnosed as active cytomegalovirus retinitis. CMV-DNA in aqueous humor was detected at the first visit and at the end of the induction period of antiviral drugs. CMV-DNA load was quantitatively detected by polymerase chain reaction after 100 µl of aqueous humor was extracted, and were converted to common logarithmic representations. Pearson correlation analysis was used to analyze the correlation between lesion area, opacity degree of lesion border and aqueous humor CMV-DNA load. Results: A total of 71 eyes from 46 patients were included and 26 was male and 20 was female. The age of the patients was 27(13, 33)years. The active lesion size of CMV retinitis was 40(12, 65) disc areas. Eight eyes (11.3%) had a suspected active lesion, 51 eyes (71.8%) had a mildly to moderately opacified lesion border, and 12 eyes (16.9%) had a severely opacified border. At the first visit, 67 eyes (94.4%) were CMV-positive, and the CMV-DNA load was 2.04×104 (6.24× 102, 1.48 ×105) copies/ml. After 2 weeks of induction therapy, the viral load was 2.47×102 (1.08× 10, 6.87 ×103) copies/ml. The correlation analysis showed that the CMV-DNA load in aqueous humor was significantly correlated with the lesion border opacity both at presentation and 2 weeks after intravitreal antiviral treatment (r=0.765, P<0.001; r=0.761, P<0.001), but was not related with the size of active fundus lesions (r=0.209, P=0.095; r=0.220, P=0.078). Conclusion: Degrees of lesion border opacity can reflect levels of aqueous viral load of CMV retinitis in patients after allogeneic hematopoietic stem cell transplantation and can become a useful measurement for investigation of CMV retinitis activity.


Asunto(s)
Retinitis por Citomegalovirus , Trasplante de Células Madre Hematopoyéticas , Humanos , Femenino , Masculino , Carga Viral , Estudios Retrospectivos , ADN
4.
Soft Matter ; 18(33): 6148-6156, 2022 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-35968815

RESUMEN

Helical micro-swimmers have markedly extended the reach of human beings in numerous fields, ranging from in vitro tasks in lab-on-a-chip to in vivo applications for minimally invasive medicine. The previous studies on the propulsive motility optimization of the micro-swimmers mainly focused on the distinct actuation principles (e.g., chemically powered, magnetic- or ultrasound energy-driven) and paid little attention to the structural design of these swimming machines themselves. The improvements of the structures can assist the externally powered motors in providing propulsion in a tiny scale and satisfy the agile locomotion demands. This paper presents the design, mechanics modeling and available experiments of a novel type of hierarchical helical swimming robot that significantly enhances the motility of the helix-based swimmers. Validated by the resistive force theory, our numerical model can well analyze the mechanical properties with a variety of geometric parameters. The motion performance of the hierarchical and conventional helical structures in low Reynolds regimes is presented, highlighting the advantages of hierarchical swimmers over the existing typical swimmers. In addition, the stability and resilience of the hierarchical swimmers can be maintained at a decent level. Moreover, the variable forward velocity resulting from the combined hierarchical structures is investigated here, which can thereby serve as a reliable design strategy. The proposed hierarchical helical design enables enticing opportunities for various device systems of medical robots and bio-integrated electronics.


Asunto(s)
Magnetismo , Natación , Humanos , Locomoción
5.
Eur Rev Med Pharmacol Sci ; 25(21): 6539-6547, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34787856

RESUMEN

Cytoplasmic dynein is a multi-subunit complex that includes cytoplasmic dynein-1 (dynein1) and cytoplasmic dynein-2 (dynein2). It participates in various basic cellular processes, including nuclear migration, mitotic spindle organization, chromosome separation during mitosis, and the location and function of numerous intracellular organelles. Retinal photoreceptor cells are terminally differentiated neurons that cannot regenerate and cannot be replaced once lost. It is thus crucial to study their development to facilitate the generation and improvement of photoreceptor disease treatments. The outer segment (OS) of photoreceptor cells is a specific sensory cilium. An increasing number of studies have shown that cytoplasmic dynein plays an essential role in the development of retinal photoreceptor cells. To date, people have done a lot of studies on the various functions of dynein in cells and have a very detailed understanding. However, the role of dynein in retinal photoreceptor cells has not been summarized in detail. This article summarizes the currently available knowledge relating to the effects and mechanisms of cytoplasmic dynein on the development and functional maintenance of retinal photoreceptor cells.


Asunto(s)
Dineínas Citoplasmáticas/metabolismo , Células Fotorreceptoras de Vertebrados/metabolismo , Animales , Humanos
6.
Zhonghua Jie He He Hu Xi Za Zhi ; 44(8): 723-728, 2021 Aug 12.
Artículo en Chino | MEDLINE | ID: mdl-34645139

RESUMEN

Objective: To explore the clinicopathological characteristics and genomic characteristics of four patients with epidermal growth factor receptor(EGFR)-mutated advanced adenocarcinoma transformed into small-cell lung cancer. Methods: Four cases of EGFR-mutated advanced adenocarcinoma of the lung transformed into small-cell lung cancer were studied by clinical data, pathological morphology, immunohistochemistry and gene detection. Result: EGFR-mutated adenocarcinoma of the lung was heterogeneous in clinical and genomic profiles, of ten characterized by RB1, TP53 and PIK3CA mutations. Its transformation into small-cell lung cancer was a particularly aggressive mechanism of drug resistance, but the machanisms were not clear NSE and other tumor indicators had low diagnostic value for transformation. Conclusions: EGFR-mutated adenocarcinoma of the lung transformed into small-cell lung cancer was one of the reasons for EGFR resistance with avery poor prognosis.


Asunto(s)
Adenocarcinoma , Neoplasias Pulmonares , Adenocarcinoma/genética , Receptores ErbB/genética , Humanos , Neoplasias Pulmonares/genética , Mutación , Inhibidores de Proteínas Quinasas
7.
Mater Today Adv ; 11: 100148, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34179746

RESUMEN

The coronavirus disease 2019 (COVID-19) pandemic had caused a severe depletion of the worldwide supply of N95 respirators. The development of methods to effectively decontaminate N95 respirators while maintaining their integrity is crucial for respirator regeneration and reuse. In this study, we systematically evaluated five respirator decontamination methods using vaporized hydrogen peroxide (VHP) or ultraviolet (254 nm wavelength, UVC) radiation. Through testing the bioburden, filtration, fluid resistance, and fit (shape) of the decontaminated respirators, we found that the decontamination methods using BioQuell VHP, custom VHP container, Steris VHP, and Sterrad VHP effectively inactivated Cardiovirus (3-log10 reduction) and bacteria (6-log10 reduction) without compromising the respirator integrity after 2-15 cycles. Hope UVC system was capable of inactivating Cardiovirus (3-log10 reduction) but exhibited relatively poorer bactericidal activity. These methods are capable of decontaminating 10-1000 respirators per batch with varied decontamination times (10-200 min). Our findings show that N95 respirators treated by the previously mentioned decontamination methods are safe and effective for reuse by industry, laboratories, and hospitals.

8.
Eur Rev Med Pharmacol Sci ; 25(5): 2172-2181, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33755954

RESUMEN

Exosomes, small membrane vesicles with a diameter of 30-100 nm, transport lipids, proteins, DNA, and RNA. Exosomes originate from endocytic vessels and are processed and released through exocytosis. They can be taken up by target cells and mediate intercellular communication. Initially, exosomes were thought to be waste products excreted by cells. However, with more research, they have been found to play important roles in physiological and pathological processes. Therefore, they are promising biomarkers for the diagnosis and treatment of a variety of disease conditions, including fundus diseases, ocular surface diseases, retinal diseases, tumors, ocular trauma, and light damage. In this review, we discuss the history, biogenesis, release, isolation, characterization, and biological functions of exosomes, as well as their future application prospects in ophthalmic diseases.


Asunto(s)
Oftalmopatías/sangre , Glaucoma/sangre , Melanoma/sangre , Neoplasias de la Úvea/sangre , Exosomas/metabolismo , Humanos
9.
Zhonghua Wai Ke Za Zhi ; 59(3): 203-209, 2021 Mar 01.
Artículo en Chino | MEDLINE | ID: mdl-33685054

RESUMEN

Objective: To investigate the efficacy and the safety of intravascular therapy for cerebrovascular ischemic tandem stenosis. Methods: Clinical data of 35 patients with symptomatic anterior circulation and posterior circulation tandem stenosis who received intravascular therapy for two sites of stenosis at the same time at Department of Neurosurgery of Peking University First Hospital from January 2013 to December 2018 were analyzed retrospectively. There were 27 males and 8 females,aged (65.6±9.4)years (range:47 to 81 years).There were 14 cases of anterior circulation tandem stenosis and 21 of posterior circulation tandem stenosis.The medical records were collected with emphasis on postoperative symptoms,imaging manifestations and modified Rankin scale(mRS) scores. Results: Sixty-eight stents were implants in to 35 patients,including 49 extracranial implants and 19 intracranial implants.The surgical success rate was 100%.The perioperative death rate was 0,and 1 patient(1/35,2.9%) had cerebral hemorrhage.All patients were followed up for 18 months.During 3 to 12 months after the intervention,1 case(1/35,2.9%) had stent restenosis,and 4 cases(4/35,11.4%) had persisted symptoms such as dizziness and weakness in limbs.All patients'mRS scores were ≤2. No new stroke occurred. During 12 to 18 months after the intervention,3 cases had in-stent restenosis,increasing the rate to 11.4% (4/35). The mRS scores of 32 patients(32/35,91.4%) were ≤2. Conclusion: Intravascular therapy for patients with symptomatic tandem stenosis is a feasible and safe procedure with good short-term outcomes.


Asunto(s)
Isquemia Encefálica/terapia , Enfermedades Arteriales Cerebrales/terapia , Constricción Patológica/terapia , Procedimientos Endovasculares , Stents , Anciano , Anciano de 80 o más Años , Implantación de Prótesis Vascular , Isquemia Encefálica/etiología , Procedimientos Endovasculares/instrumentación , Procedimientos Endovasculares/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento
10.
Nat Commun ; 11(1): 235, 2020 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-31932585

RESUMEN

Topological superconductors have attracted wide-spreading interests for the bright application perspectives to quantum computing. Cu0.3Bi2Se3 is a rare bulk topological superconductor with an odd-parity wave function, but the details of the vector order parameter d and its pinning mechanism are still unclear. Here, we succeed in growing CuxBi2Se3 single crystals with unprecedented high doping levels. For samples with x  = 0.28, 0.36 and 0.37 with similar carrier density as evidenced by the Knight shift, the in-plane upper critical field Hc2 shows a two-fold symmetry. However, the angle at which the Hc2 becomes minimal is different by 90° among them, which indicates that the d-vector direction is different for each crystal likely due to a different local environment. The carrier density for x  = 0.46 and 0.54 increases substantially compared to x ≤ 0.37. Surprisingly, the in-plane Hc2 anisotropy disappears, indicating that the gap symmetry undergoes a transition from nematic to isotropic (possibly chiral) as carrier increases.

11.
Phys Rev Lett ; 121(16): 167004, 2018 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-30387623

RESUMEN

A magnetic order can be completely suppressed at zero temperature (T), by doping carriers or applying pressure, at a quantum critical point, around which physical properties change drastically. However, the situation is unclear for an electronic nematic order that breaks rotation symmetry. Here, we report nuclear magnetic resonance studies on NaFe_{1-x}Co_{x}As where magnetic and nematic transitions are well separated. The nuclear magnetic resonance spectrum is sensitive to inhomogeneous magnetic fields in the vortex state, which is related to London penetration depth λ_{L} that measures the electron mass m^{*}. We discovered two peaks in the doping dependence of λ_{L}^{2}(T∼0), one at x_{M}=0.027 where the spin-lattice relaxation rate shows quantum critical behavior, and another at x_{c}=0.032 around which the nematic transition temperature extrapolates to zero and the electrical resistivity shows a T-linear variation. Our results indicate that a nematic quantum critical point lies beneath the superconducting dome at x_{c} where m^{*} is enhanced. The impact of the nematic fluctuations on superconductivity is discussed.

12.
Fa Yi Xue Za Zhi ; 34(6): 659-664, 2018 06.
Artículo en Chino, Inglés | MEDLINE | ID: mdl-30896108

RESUMEN

Due to the concealment and incidence higher than reported statistics, infanticide should attract the attention of legal medical experts. The infanticide process has common behavioral characteristics. The perpetrators are most frequently biological mothers who are unmarried, with inferior education, and lack of routine pregnancy tests. Medicolegal identification of infanticide cases includes identification of live births and causes of death. Besides the classical lung floating test, there are other methods to identify live births such as pulmonary interstitial emphysema, CT imaging examination, immunohistochemical examination of umbilical cord vitality markers. Neonatal line measurement is the only way to identify live births in corpse with severe decomposition. The main causes of death in infanticide are mechanic asphyxia and fatal head trauma. Shaken baby syndrome, as a common abusive head trauma, is pathologically characterized by the triad of encephalopathy, subdural haemorrhage (SDH) and retinal haemorrhage (RH). During the autopsy of suspected shaking baby syndrome, in addition to carefully examining cervical cord, the possibility of pathological temporal lobe hemorrhage should also be ruled out.


Asunto(s)
Traumatismos Craneocerebrales , Infanticidio , Síndrome del Bebé Sacudido , Traumatismos Craneocerebrales/etiología , Medicina Legal , Hematoma Subdural , Humanos , Lactante , Hemorragia Retiniana/etiología
13.
Zhonghua Yi Xue Za Zhi ; 97(30): 2372-2378, 2017 Aug 08.
Artículo en Chino | MEDLINE | ID: mdl-28822457

RESUMEN

Objective: To evaluate the safety and efficacy of peripheral arterial disease patients with critical limb ischemia who accepted BSX or EVT. Methods: According to the requirements of systematic review, we searched MEDLINE (1980-2014), Emabse (1980-2014), Journals @ Ovid Full Text (1980-2014) databases, selected literature and extracted data, meta-analysis was performed through STATA11.2. Results: A total of 17 studies (3 RCTs, 14 non-randomized studies) and 5 515 patients (BSX group: 2 454, EVT group: 2 769) were deemed eligible. Meta-analysis showed there were no differences between the two groups in 30-day mortality (OR=1.110, P=0.523). However, BSX was significantly associated with increasing overall complications (OR=2.456, P=0.003), infections (OR=3.163, P<0.001) and thrombosis (OR=3.069, P=0.002), but showed a reduction in dissection and pseudoaneurysm (OR=0.537, P=0.012). During the follow-up, BSX had significant advantages. The 1-year and 3-year primary patency of BSX patients were higher than EVT group (1 year, OR=1.415, P=0.008; 3 years, OR=1.619, P<0.001); so were in secondary patency( 1 year, OR=2.156, P<0.001; 3 years, OR=2.547, P<0.001). Meanwhile, the 5-year overall survival rate was also higher in BSX group (OR=1.243, P=0.007). Conclusions: EVT has potential advantages in reducing surgical trauma and early postoperative complications, shortening hospital stay and so on. Concerning long-term results, BSX is better in reducing long-term mortality and improving long-term patencies than EVT group.


Asunto(s)
Isquemia , Enfermedad Arterial Periférica , Amputación Quirúrgica , Angioplastia de Balón , Humanos , Estudios Retrospectivos , Factores de Riesgo , Resultado del Tratamiento
14.
Genet Mol Res ; 16(2)2017 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-28407193

RESUMEN

Haematococcus pluvialis, as the most potential natural source of astaxanthin, which is a powerful antioxidant with high economic value, has attracted more and more scientific attention in recent years. An in-depth understanding of the mechanism for how H. pluvialis produces astaxanthin requires the intensive investigations on its genetic information. In particular, many reported studies were based on a variety of RNA analyses. However, it is difficult to extract RNA with high quality and quantity from H. pluvialis, because of the blockage from its thick cell wall and contamination by a large quantity of pigments, polysaccharides, and lipids. Therefore, we proposed an optimized Trizol-based RNA extraction method for H. pluvialis by investigating the effect of cell wall broken ways, algal strains, and cell growth status on total RNA isolation. Using this rapid, convenient, and cost-saving method, isolated H. pluvialis RNA had high quantity and quality (with an RNA integrity number of 7.0 and a concentration of 1604.1 ng/µL) equivalent to that isolated by commercial kit, enabling its applications into downstream RNA analyses.


Asunto(s)
Chlorophyta/química , ARN de Planta/química , Fraccionamiento Celular/métodos , Fraccionamiento Químico/métodos , ARN de Planta/normas
15.
Zhonghua Wai Ke Za Zhi ; 54(12): 891-893, 2016 Dec 01.
Artículo en Chino | MEDLINE | ID: mdl-27916029

RESUMEN

Bypass surgery(BSX) and endovascular therapy(EVT) are the most important therapeutic method to critical limb ischemia.EVT has potential advantages in reducing surgical trauma and early postoperative complications, shortening hospital stay and so on. Concerning long-term results, BSX is better in reducing long-term mortality and improving long-term patency than EVT group. Therefore, control indications reasonably and select individualized methods, avoid the abuse of EVT are more meaningful for patients.


Asunto(s)
Enfermedad Arterial Periférica/cirugía , Injerto Vascular , Anciano , Procedimientos Endovasculares , Femenino , Humanos , Isquemia , Recuperación del Miembro , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Estudios Retrospectivos , Resultado del Tratamiento
16.
Proc Math Phys Eng Sci ; 472(2193): 20160504, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27713665

RESUMEN

A model is proposed based on a Fourier series method to analyse the interactive bending wrinkling behaviour of inflated beams. The whole wrinkling evolution is tracked and divided into three stages by identifying the bifurcations of the equilibrium path. The critical wrinkling and failure moments of the inflated beam can then be predicted. The global-local interactive buckling pattern is elucidated by the proposed theoretical model and also verified by non-contact experimental tests. The effects of geometric parameters, internal pressure and boundary conditions on the buckling of inflated beams are investigated finally. The results reveal that the interactive buckling characteristics of an inflated beam under bending are more sensitive to the dimensions of the structure and boundary conditions. We find that for beams which are simply supported at both ends or clamped and simply supported, boundary conditions may prevent the wrinkling formation. The results provide significant support for our understanding of the bending wrinkling behaviour of inflated beams.

17.
Appl Microbiol Biotechnol ; 100(24): 10295-10306, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27459869

RESUMEN

A strategy to supply molecular oxygen for microbial calcium precipitation was developed for the first time. Firstly, a controlled oxygen-releasing tablet (ORT) containing CaO2 and lactic acid with a suitable ratio of 9:1 was developed. It can provide a stable oxygen supply and maintain pH in the range of 9.5-11.0 for 45 days while contacting with water. In the presence of oxygen, a self-healing bacterium H4 spores germinated more effectively and maintained high metabolic activity. Furthermore, H4 vegetative cells induced 50 % more calcium precipitation than that obtained without oxygen supply. Finally, a binary self-healing system containing bacterial spores and ORT was established. The calcium precipitation experiments showed that H4 in the binary self-healing system precipitated 27.5 mM calcium with oxygen supply after 32 days and dissolved oxygen (DO) concentration of the solution decreased from 15 to 4 mg l-1, while only 6.9 mM calcium precipitation was obtained without oxygen supply. This work can disclose the effect of oxygen on microbial calcium precipitation and further lay a foundation for the establishment of ternary self-healing system containing bacteria, ORT, and nutrients, which will be promising for the self-healing of cracks deep inside the concrete structure.


Asunto(s)
Bacillus/metabolismo , Calcio/metabolismo , Materiales de Construcción/microbiología , Oxígeno/metabolismo , Esporas Bacterianas/metabolismo , Comprimidos/metabolismo , Bacillus/crecimiento & desarrollo , Precipitación Química , Concentración de Iones de Hidrógeno , Ácido Láctico/metabolismo , Esporas Bacterianas/crecimiento & desarrollo
18.
Nanoscale ; 8(8): 4672-80, 2016 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-26853057

RESUMEN

Repeatable fabrication of sensitive plasmonic substrates through a simple procedure has become a major challenge for SERS-based sensing and imaging. Herein, a new class of high-performance SERS substrates, including pyramid, ridged-hexagon, and quasi-triangle nanostructures, is successfully fabricated based on the nanosphere lithography technique and anisotropic wet etching. Using the wafer-scale Cr-hole array as the etching mask, cavity-templates of various configurations are fabricated by the orientation-dependent wet etching technique, from where the nanostructure arrays are finally peeled-off. The anisotropic wet etching on (100), (110), and (111) silicon wafers has been systematically studied at the nanoscale revealing the formation mechanism of these cavity-templates. The peeled-off nanostructure arrays provide high-density tips and/or gaps (about 2.5 × 10(7) mm(-2)) and thus facilitate the generation of "hot spots". The distribution of the electromagnetic field is visualized by the finite difference time domain calculation. And the calculation results are validated by SERS characterization. The SERS enhancement factors of these substrates are in the order of 10(6)-10(7), with the maximum enhancement factor of 1.32 × 10(7) yielded by the ridged-hexagon arrays. The proposed nanostructure arrays present excellent homogeneity and reproducibility (with the largest relative standard deviation of 16.43%) for the reason that the SERS-active substrates are peeled-off from an identical template. The cost-effective fabrication, high sensitivity, good homogeneity and well-performed reproducibility demonstrate that these orientation-dependent NSs are good candidates for SERS-based in vitro and in situ detection and biosensing.

19.
Small ; 10(15): 3045-9, 2014 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-24729306

RESUMEN

A simple, scalable method is reported to fabricate ordered hetero-structures of organic materials using template-directed growth. The 3D extension of the structures is firstly determined by pre-pattern size and deposition amount, and can further be in situ tuned by annealing at appropriate temperature.

20.
Cell Death Dis ; 5: e1151, 2014 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-24675469

RESUMEN

Disturbing mitotic progression via targeted anti-mitotic therapy is an attractive strategy for cancer treatment. Therefore, the exploration and elucidation of molecular targets and pathways in mitosis are critical for the development of anti-mitotic drugs. Here, we show that cell division cycle 5-like (Cdc5L), a pre-mRNA splicing factor, is a regulator of mitotic progression. Depletion of Cdc5L causes dramatic mitotic arrest, chromosome misalignments and sustained activation of spindle assembly checkpoint, eventually leading to mitotic catastrophe. Moreover, these defects result from severe impairment of kinetochore-microtubule attachment and serious DNA damage. Genome-wide gene expression analysis reveals that Cdc5L modulates the expression of a set of genes involved in the mitosis and the DNA damage response. We further found that the pre-mRNA splicing efficiency of these genes were impaired when Cdc5L was knocked down. Interestingly, Cdc5L is highly expressed in cervical tumors and osteosarcoma. Finally, we demonstrate that downregulation of Cdc5L decreases the cell viability of related tumor cells. These results suggest that Cdc5L is a key regulator of mitotic progression and highlight the potential of Cdc5L as a target for cancer therapy.


Asunto(s)
Puntos de Control del Ciclo Celular , Proteínas de Ciclo Celular/metabolismo , Mitosis , Precursores del ARN/metabolismo , Empalme del ARN/genética , Proteínas de Unión al ARN/metabolismo , Proteínas de Ciclo Celular/deficiencia , Supervivencia Celular , Cromosomas Humanos/metabolismo , Daño del ADN/genética , Enzimas Reparadoras del ADN/metabolismo , Regulación hacia Abajo , Regulación Neoplásica de la Expresión Génica , Técnicas de Silenciamiento del Gen , Células HeLa , Humanos , Cinetocoros/metabolismo , Microtúbulos/metabolismo , Mitosis/genética , Proteínas Nucleares/metabolismo , Factores de Empalme de ARN
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