Factors associated with non-lifting of colorectal mucosal lesions.

BACKGROUND: Endoscopic submucosal dissection (ESD) is an effective treatment for colorectal tumors. However, lesions that cannot be lifted after submucosal injection are not indication for ESD. This is because the procedure is difficult, and the lesions are often considered as tumor invasion or submucosal fibrosis. The aims of this study are to evaluate the efficacy and safety of ESD for non-lifting lesions and to analyze the causes of non-lifting phenomenon. METHODS: This retrospective study included 29 patients with non-lifting colon lesions resected by ESD from February 2018 to September 2021. Cases were observed for demographics, endoscopic findings, treatment outcomes, adverse events and endoscopic follow-up. We studied the pathological features of lesions to explore the reasons for non-lifting. RESULTS: Among 29 cases of non-lifting lesions, 20 lesions (69.0%) were 30 mm in diameter or larger. Most of lesions (96.6%) were non-lifting in center, and only one lesions (3.4%) had non-lifting of one side. The en bloc and curative resection rates of ESD were 100 and 86.2%, respectively. There was one (3.4%) delayed bleeding, no perforations and other complications. No tumor recurrence occurred during the follow-up period. For pathological features, 16 (55.2%) non-lifting lesions had submucosal fibrosis and only 4 cases (13.8%) had deep submucosal invasion. There were 9 cases (31.0%) of non-lifting lesions due to musculo-fibrous of muscularis propria anomaly (MMPA). CONCLUSION: MMPA is another reason for non-lifting signs besides invasive carcinomas and submucosal fibrosis. ESD should be considered in patients with large non-lifting adenoma instead of surgery.

Long noncoding RNA TNFRSF10A-AS1 promotes colorectal cancer through upregulation of HuR.

BACKGROUND: Recent studies have emphasized the emerging importance of long noncoding RNAs (lncRNAs) in colorectal cancer (CRC). However, the functions and regulatory mechanisms of numerous lncRNAs in CRC have not been fully elucidated. AIM: To explore the functional role and underlying molecular mechanisms of lncRNA TNFRSF10A-AS1 in CRC. METHODS: TNFRSF10A-AS1 expression was measured by quantitative real-time polymerase chain reaction in CRC, and the relationship between TNFRSF10A-AS1 levels and the clinicopathological features of CRC patients was analyzed. The effect of TNFRSF10A-AS1 expression on CRC proliferation and metastasis was examined in vitro and in vivo. Mechanistically, we investigated how TNFRSF10A-AS1 is involved in CRC as a competitive endogenous RNA. RESULTS: TNFRSF10A-AS1 was expressed at a high level in CRC and the upregulation of TNFRSF10A-AS1 was associated with advanced T grade and tumor size in CRC patients. A functional investigation revealed that TNFRSF10A-AS1 enhanced the proliferation, migration ability and invasion ability of colon cancer cells in vitro and in vivo. A mechanistic analysis demonstrated that TNFRSF10A-AS1 acted as a miR-3121-3p molecular sponge to regulate HuR expression, ultimately promoting colorectal tumorigenesis and progression. CONCLUSION: TNFRSF10A-AS1 exerts a tumor-promoting function through the miR-3121-3p/HuR axis in CRC, indicating that it may be a novel target for CRC therapy.

[Effect of KCI additive on laser-induced soil plasma radiation].

In order to improve laser-induced breakdown spectroscopy for low-level elements testing capability, the enhancement effects of KCl additive on the emission spectra of soil samples were studied. The laser spectrum analytical system is composed of a high-energy neodymium glass laser ablating samples, a multifunctional and automatic scanning spectrometer, and a CCD data acquisition system recording plasma spectra. The electron temperature and electron density of plasmas were calculated by measuring spectral line intensity and stark broadening respectively. The experimental results showed that with the increase in the KCl additive, the spectral intensity, signal-to-background ratio, the electron temperature and the electron density all went up firstly and then down. When 15% KCl was added, the radiation intensity of plasma reached the maximum value, the spectral lines intensity of element Mn, Fe, and Ti increased by 2.23, 1.13 and 2.04 than that without additive respectively, the spectral signal-to-background ratio increased by 1.33, 0.89 and 0.94 times respectively; while the electron temperature and electron density of plasmas were heightened by 14% and 38% respectively.

[Enhancing effect of sample additive on laser-induced plasma radiation].

In order to improve the radiation characteristic of laser-induced plasma, with the national standard soil taken as the target sample, a laser spectrum analytical system which composed of a high-energy neodymium glass laser, a multifunctional and compact integrated spectrometer, and a CCD detector was used to detect the influence of the NaCl sample additive on the laser plasma radiation intensity. The electron temperature and the electron density of the plasmas were also calculated from the lines intensity and stark broadening of emission spectral line respectively. The experimental results indicated that with the increase in the NaCl additive, the spectral intensity, signal-to-background ratio, the electron temperature, and the electron density all went up firstly and then down. When 15% NaCl was added, the radiation intensity of the plasma reached the maximum value, the spectral lines intensity of element Mn, K, Fe, and Ti increased by 39.2%, 42.5%, 53.9% and 33.8% compared to that without additive respectively, the spectral signal-to-background ratio increased by 64.4%, 84.39, 44.55% and 58.2% respectively, while the electron temperature and the electron density of the plasmas were heightened by 0.17 times and 0.36 times respectively.

[Properties of energy transfer in two host materials doped with Ir(ppy)3 and Rubrene].

The devices with phosphorescent material tris(2-phenylpyridine)iridium [Ir(ppy)3] and fluorescent material 5,6,11, 12-tetraphenylnaphthacene [Rubrene] as dopants in two kinds of host were constructed in the present study. Respectively, the two kinds of host are polyvinylcarbazole [PVK] and 4,4'-N,N-dicarbazole-biphenyl [CBP]. We studied the properties of energy transfer between host materials and dopants. Firstly, the absorption and photoluminescence spectra of PVK, CBP, Ir(ppy)3 and Rubrene were measured. The spectral overlap between the photoluminescence of PVK and the absorption spectrum of Ir(ppy)3 is larger than that of Rubrene. The result of the spectral overlap for CBP is the same as PVK. It was shown that the energy transfer from the two host materials to Ir(ppy)3 is stronger than that to Rubrene. In addition, the energy transfer from Ir(ppy)3 to Rubrene is possible according to their absorption and photoluminescence spectra. We compared the electroluminescence properties of different devices. In devicel of ITO/PVK : Rubrene : Ir(ppy)3 (100 : 5 : x)/BCP(10 nm)/Alq3 (20 nm)/Al and device 2 ITO/CBP : Rubrene : Ir(ppy)3 (100 : 5 : x)/BCP(10 nm)/Alq3 (20 nm)/Al(x = 0, 3), under the same DC bias, the electroluminescence results show that energy transfer from host to Rubrene through Ir(ppy)3 is the main mechanism. And energy transfer is much more efficient in CBP as host than in PVK. In addition, at the same voltage, the light power of the device doped with Ir(ppy)3 and Rubrene is obviously stronger than that of the device doped with Rubrene only. When the concentration of Ir(ppy)3 increases, the light power decreases at the same voltage, and the effect of concentration quenching is enhanced.

[Luminescence characteristics of PVK doped with Ir(ppy)3].

With the increasing development of organic light emitting devices (OLED), interest in the mechanisms of charge carrier photogeneration, separation, transport and recombination continues to grow. Electromodulation of photoluminescence has been used as an efficient probe to investigate the evolution of primary excitation in all electric field. This method can provide useful information on carrier photogeneration, the formation and dissociation of excitons, energy transfer, and exciton recombination in the presence of electric field. The operation of OLED brings electrons and holes from opposite electrodes and generates singlet and triplet excitons. However, triplet excitons are wasted because a radiative transition from triplets is spin-forbidden. Spin statistics predicts that singlet-to-triplet ratio is 1 : 3 in organic semiconductors. One way to harvest light from triplet excitons is to use phosphorescent materials. These materials incorporate a heavy metal atom to mix singlet and triplet states by the strong spin-orbit coupling. As a result, a spin forbidden transition may occur allowing an enhanced triplet emission. Among phosphorescent materials, Ir(ppy)3 has attracted much attention because of its short triplet lifetime to minimize the triplet-triplet annihilation. High quantum efficiencies have been obtained by doping organic molecules and in polymers with Ir(ppy)3. In the present paper, the photoluminescence and electroluminescence spectra of Ir(ppy)3 doped PVK film are measured at room temperature. The device structure is ITO/PEDOT : PSS/PVK Ir(ppy)3/BCP/Alq3/Al. The results show that the luminescence capabilities of devices are different when the concentration of Ir(ppy)3 is different. When the concentration of Ir(ppy)3 is suitable, the luminescence of PVK is lower but that of Ir(ppy)3 is stronger relatively, indicating that the energy transfer from the host materials to the guest materials is sufficient. It is concluded that the device with 5% of Ir(ppy)3 has the best luminescence properties according to its light power-current-voltage curve, meaning that the best concentration of Ir(ppy)3 in such kind of device is 5%.

[Effects of PBD on the luminescence properties of PVK: Ir(ppy)3].

The effects of PBD on the luminescence properties of PVK : Ir(ppy)3 codoped with PBD with lower concentration were investigated. Two kinds of devices with the structures of ITO/PVK : Ir(ppy)3/PBD/Al and ITO/PVK : Ir(ppy)3 : PBD/ Al were fabricated. PVK emission appears in the electroluminescence (EL) spectra of ITO/PVK : Ir(ppy)3/PBD/Al. The reason is that the Forster energy transfer is not efficient enough in the emission layer, and then the emission layer was doped with PBD. A set of devices were fabricated with the configuration of ITO/PVK : Ir(ppy)3 : PBD/BCP/Al. The doping weight ratio of PVK : Ir(ppy)3 was fixed as 100 : 1, and the weight ratio of PBD changed from 100 : 0 (PVK : PBD) to 100 : 20. The photoluminescence (PL) spectra and electroluminescence (EL) spectra of these devices were measured. Through the analysis of their luminescence, it was found that the brightness of these devices codoped with PBD is improved. The brightness of these devices increases with increasing PBD doping ratio as the ratio does not exceed 100:10 (PVK : PBD). The PBD codoping enhances the injection and transportation of electron, resulting in the enhanced carrier recombination probability. If the doping ratio of PBD exceeds 100 : 10 (PVK : PBD), the brightness of the device decreases. There are two reasons. One is that the superfluous PBD causes the carriers to be imbalanced and induces a larger leakage current. The other is that the superfluous PBD may block the hoping of holes or electrons between the PVK chains. The brightness is the strongest when the weight ratio of PVK to PBD is 100 : 10.

[Effects of chemical sensitization on photoelectron time-resolved spectrum].

The time-resolved spectra of free photoelectrons and shallow-trapped electrons in the T-grains AgBrI emulsion were simultaneously detected with microwave absorption and dielectric spectrum detection technique. The results indicate that the electron trap effects of sulfur sensitization centers and sulfur-plus-gold sensitization centers are different with equal quantities of Na2S2O3 added. The sulfur sensitization centers acted as a deep electron trap to pick up the electronic decay because of increasing the number of deep trapped electrons, while the sulfur-plus-gold sensitization centers as a shallow electron trap decrease the electronic decay through effectively controlling the recombination between the electrons and the holes. The depth of sulfur-plus-gold sensitization center is shallower than that of sulfur sensitization center after the KAuCl4 is added. The effects of sulfur sensitization center and sulfur-plus-gold sensitization center on the photoelectron decay are different in different sections of decay curves through the change in electron time-resolved spectra.

[Photoelectron decay time-resolved spectrum of AgCl crystals doped with K4Ru(CN)6 complex].

Microwave absorption and film dielectric spectrum detection technology was used to study the influence of complex K4Ru (CN)6 on the photoelectron decay time-resolved spectrum of cubic AgCl crystals illuminated in this paper. The results indicate that the influence of the doping content and doping position of the complex K4Ru(CN)6 on the photoelectron decay time-resolved spectrum is evident. The photoelectron decay process of this emulsion is slowest, and the photoelectron lifetime is longest when doped with K4Ru (CN)6 of 2.45 x 10(-5) mol x (mol Ag)(-1) at doping positions of 75% Ag.

[The characteristic of photoelectron decay spectra in silver halide microcrystals].

Photoelectrons plays an important role in the latent image formation process of silver halide materials, and the decay characteristic of photoelectrons are dependent on the structure of silver halide microcrystals to a great extent. In this paper, the decay spectra of free photoelectrons and shallow-trapped electrons were obtained by optics and microwave double resonance technology. The depth and density of electron traps in silver halide microcrystals were discussed. Moreover, using the lifetime of free photoelectrons, the optimal doping amount of shallow electron trap dopants was found by analyzing the distribution condition of electron traps in silver halide.