Search

BACKGROUND: Angiographic computed tomography (CT) is useful in various medical contexts, but little research has been presented regarding the application of cone beam CT (CBCT) in airway stenting. This study set out to evaluate the clinical feasibility of using CBCT in airway stent placement in a single-center retrospective cohort. METHODS: A total of 228 patients with stenosis or fistula diseases were treated with metallic airway stents in the First Affiliated Hospital of Zhengzhou University from January 1, 2015, to December 31, 2018. Of them, 128 patients underwent fluoroscopy-guided airway stenting. CBCT scanning was performed on the other 100 patients during and after treatment, and their images were compared with those from postoperative multidetector CT (MDCT). The outcomes and complications in the CBCT-guided and fluoroscopy-guided groups were also assessed via Pearson’s χ(2) test or Fisher’s exact test. RESULTS: Tracheal stenting was performed successfully on the first attempt for 90 patients in the CBCT-guided group and 123 patients in the fluoroscopy-guided group. The mean measured diameters of the central airway in the CBCT images and MDCT images were 18.2±2.81 and 19.0±2.33 mm, respectively, and the mean lengths were 58.7±16.82 and 58.5±17.06 mm, respectively. In the CBCT-guided group and the fluoroscopy-guided group, the mean scores for visibility of the distal bronchus were 3.7±0.49 and 3.9±0.34, respectively; the mean scores for the pulmonary parenchyma were 3.3±0.71 and 3.9±0.31, respectively; and the mean scores for the airway above the upper stent graft were 1.8±0.41 and 4.0±0.20, respectively. Two of the three anatomical areas were reproduced in a diagnostically relevant way. The major complications rate was 7% and 19% in the CBCT-guided and fluoroscopy-guided groups, respectively. CONCLUSIONS: CBCT produces images with sufficient quality to replace MDCT as a reasonable control measure after stent implantation, and its use during surgery reduces complications relating to airway stent placement.

Lithium-sulfur (Li–S) batteries have received widespread attention for the reason that their specific capacity is dramatically higher than that of current lithium-ion batteries. However, Li–S batteries still have problems such as poor conductivity, severe “shuttle effect”, huge volume changes in the cathode, and lithium dendrites. Here, we report the introduction of carbon nanotubes (CNTs) into metal-organic frameworks (MOFs)-Cu-BTC and obtained Cu-BTC/CNTs with a three-dimensional structure by hydrothermal method. This structure solves the problem of inefficient electrochemical performance caused by poor conductivity when using Cu-BTC to adsorb lithium polysulfides (LiPSs). At the same time, the abundant porous structure is capable of effectively alleviating the volume expansion of the cathode during the reaction process. More importantly, Cu-BTC/CNTs catalyzes redox reactions, greatly improves the catalytic effect of Cu-BTC on LiPSs and the utilization of sulfur. As a result, The Cu-BTC/CNTs/S as sulfur host in the Li–S batteries cathode delivers an initial discharge of 924.69 mAh/g at 0.2C. Even at a high rate of 1C, it also exhibits a specific capacity of 805.28 mAh/g and still maintains 406.68mAh/g after 200 cycles at 1C. The above results indicate that the introduction of CNTs not only improves the overall conductivity of the material but also can fully exert the catalytic effect of Cu-BTC on the conversion of LiPSs. This work provides a convenient strategy to promote the conversion of LiPSs along with improving the catalytic activity of MOFs in Li–S batteries.

Metal–organic frameworks (MOFs) exhibit great potential for lithium-sulfur (Li–S) batteries because of their unique characteristics such as the high surface area, the precise structure, and the tunable porous environment. However, their low binding energy with sulfur and poor absorbability of polysulfides leads to the “shuttle effect,” reducing the stability of MOFs. With strong bonding ability to sulfur, indium-based MOFs, in which the indium (In) shows the Lewis acid character, can form the stable chemical bonds of In-S. Based on it, we used the indium-based MOF-CPM-200 as a carrier, combined with the conductive multi-walled carbon nanotubes (CNT) and sulfur to construct the composite cathode material of CPM-200/CNT@S. The unique composite structure for cathode materials of Li–S batteries can inhibit the “shuttle effect” and enhance conductivity. The initial discharge capacity of the CPM-200/CNT@S can reach as high as 1400 mAh∙g−1 and maintain a capacity of about 840 mAh∙g−1 after 100 charge–discharge cycles at 0.1 C, the coulombic efficiency approaches 100%. This work offers a new strategy for constructing the MOFs-based cathode materials for Li–S batteries with high performance.

To uncover the molecular mechanism underlying glucocorticoid-induced loss of mitochondrial integrity in skeletal muscles, studies were performed to investigate whether the peroxisome proliferator-activated receptor γ coactivator 1 (PGC-1)-mediated pathway was involved in this process. In an in vivo trial, 3 groups of 30-d-old Arbor Acres male broilers were randomly subjected to one of the following treatments for 7 days: corticosterone (CORT, 30 mg/kg diet), control (blank), and pair-feeding (restricted to the same feed intake as for the CORT treatment), each with 6 replicates of 15 birds. Mitochondrial abundance, morphology, and function were determined in the pectoralis major and biceps femoris muscles. In an in vitro trial, a primary culture of embryonic chick myotubes was incubated with a serum-free medium for 24 h in the presence or absence of CORT (0, 200, and 1,000 nM). Results showed that CORT destroyed mitochondrial ultrastructure (p < 0.01), and decreased the enzymatic activity and protein expression of respiratory chain complexes (p < 0.05), leading to an inferior coupling efficiency (p < 0.05). As reflected by a decline in mitochondrial density (p < 0.01) and mitochondrial DNA copy number (p < 0.05), CORT reduced mitochondrial contents. Among all three PGC-1 family members, only PGC-1β was down-regulated by CORT at the protein level (p < 0.05). Some aspects of these responses were tissue-specific and seemed to result from the depressed feed intake. Overall, CORT may impair mitochondrial biogenesis and oxidative phosphorylation in a PGC-1β-dependent manner in chicken muscles.

Studies in mammals have shown that adiponectin is secreted mainly by adipocytes, and it plays a crucial role in glucose and lipid metabolism in muscles. Clarifying the crosstalk role of adiponectin between adipose tissue and skeletal muscle tissue is very important for internal homeostasis. The glucose and lipid metabolism of chicken is different from that of mammals, and the role of adiponectin in chickens is unclear. Therefore, it is of great significance to study the effect and mechanism of adiponectin on lipid metabolism in chickens. In this study, the regulating effect of adiponectin on lipid metabolism in chicken myoblasts was explored by adding a certain concentration of exogenous recombinant adiponectin. Results showed that adiponectin reduced intracellular lipid content, increasing the mRNA expression of adiponectin receptor and cellular uptake of glucose and fatty acids. In addition, adiponectin activated the 5′ adenosine monophosphate activated protein kinase (AMPK) signaling pathway. The above results suggested that adiponectin reduced intracellular lipid content, mainly by binding to adiponectin receptor, activating AMPK pathway, increasing cellular uptake of glucose and fatty acids, and promoting lipid oxidation.

The determination of the local cooling rate has a great significance in optimizing the parameters of electroslag remelting (ESR) and improving the quality of the ingots. An innovative method was proposed for calibrating the local cooling rate of M42 high-speed steel (HSS) in the ESR process. After resolidification at different cooling rates under high-temperature laser confocal microscopy, the carbide network spacing of the specimen was observed using a scanning electron microscope. A functional relationship between the cooling rate and average carbide network spacing was established. The average local cooling rate of the solidification process of the M42 HSS ingot was calibrated. The results show that the higher the cooling rate, the smaller the network spacing of the carbides. For the steel ingot with a diameter of 360 mm, the average local cooling rate was 0.562 °C/s at the surface, 0.057 °C/s at the position of 0.25D (where D is the diameter of the ingot), and 0.046 °C/s at the center of the ingot.

The as-cast M42 high-speed steels containing different contents of cerium (Ce) were manufactured to investigate the effects of Ce on the solidification structures at the micro- and macroscale. The results indicate that the addition of Ce could modify MgO·Al2O3 and MnS into the Ce-containing inclusions. The addition of Ce refined the dendrite structure and eutectic carbides, which can be ascribed to the heterogeneous nucleation of primary austenite on Ce2O2S or Ce2O3 and the increase in both the compositional supercooling at the dendrite forefront and the restriction on the dendrites coarsening. Both the secondary dendrite arm spacing (SADS) and total eutectic carbides content decrease gradually with increasing Ce content. M2C and M6C carbides are the predominant precipitates. The increase of Ce content made the morphology of M2C carbides change from long lamellar or straight-rod morphology into shorter curved-rod or honeycomb morphology because of the overgrowth of eutectic austenite, but it had no significant effect on the morphology of M6C carbides. Ce2O2S and Ce2O3 can serve as the very effective heterogeneous nucleation sites for M6C carbides because of the low lattice disregistry between them, hence Ce addition improved markedly the macroscopic distribution of M6C carbides in the cast ingot and promoted the formation of M6C carbides at the expense of M2C carbides.

High-nitrogen (N) austenitic stainless steel (Cr–Mn–N series) is commonly used for non-magnetic drill collars, which exhibits excellent mechanical properties and corrosion resistance. The effects of N content (0.63 to 0.86 wt.%) on the pitting corrosion behavior of the experimental non-magnetic drill collar steel were investigated using the electrochemical tests and immersion tests. Besides, X-ray photoelectron spectroscopy was used to analyze the constitution of the passive film. The results show that with the enhancement of N content from 0.63 to 0.86 wt.%, the metastable pitting corrosion sensitivity of the tested materials in 3.5 wt.% NaCl solution decreased and the pitting corrosion resistance increased. Meanwhile, the corrosion rate in 6 wt.% FeCl3 solution at 30 °C decreased from 10.40 to 4.93 mm/a. On the other hand, nitrogen was concentrated in the form of ammonia (NH4+ and NH3) on the outermost surface of the passive films. The contents of Cr2O3 and Fe2O3 raised in the passive films, together with the content of CrN, at metal/film interface increased as N content increased from 0.63 to 0.86 wt.%, which facilitated protective ability of the passive films, thus contributing to higher pitting corrosion resistance.

The microstructure evolution and intergranular corrosion (IGC) behavior of high nitrogen martensitic stainless steels (MSSs) by partial replacing C by N were investigated by using microscopy, X-ray diffraction, nitric acid tests and double-loop electrochemical potentiokinetic reactivation (DL-EPR) tests. The results show that the partial replacement of C by N first reduces and then increases the size and content of precipitates in high nitrogen MSSs, and converts the dominant precipitates from M23C6 to M2N, furthermore first improves and then deteriorates the IGC resistance. The high nitrogen MSS containing medium C and N contents provides good combination of mechanical properties and IGC resistance.

We elucidated the significance of partial substitution of C by N in three high nitrogen Fe-15Cr-1Mo-C-N martensitic stainless steels (MSSs), and particularly its influence on microstructural features and the strength-toughness balance. The results show that partial substitution of C by N avoided the formation of coarse intergranular carbides and caused significant changes in the type of carbonitrides from M23C6 to M23C6+M2N and finally to M2N. Meanwhile, partially replacing C by N first increased and then decreased the effective grain size, the fraction of retained austenite, and the plate martensite, while the variations of the amount of carbonitrides and dislocation density were just the opposite. The microstructural evolutions with varying (C+N) contents played a crucial role in determining the overall properties: the 0.35C-0.37N steel exhibited an improved impact toughness (~ 86.1 J), which was 2 or 3 times higher than those of 0.50C-0.16N and 0.20C-0.54N steels, even at a strength level of over 2 GPa. The contributions of partial substitution of C by N on the strengthening mechanisms of MSSs were also systematically revealed by combining the experimental and theoretical data.

To evaluate the efficacy and safety of brachytherapy with double-strand42 patients with obstructive jaundice because of extrahepatic cholangiocarcinoma were enrolled. 22 patients (group A) received a biliary stent with common drainage tube implantation, and 20 patients (group B) received a biliary stent with double-strandThere was no significant difference in the length, location and pathological stage of biliary stenosis between the two groups. There was no significant difference in TBIL, DBIL, IgA, IgG, IgM, alanine aminotransferase and WBC count between the two groups before or after PTCD (P 0.05). Three months after PTCD, tumors growth in group A and tumors shrinkage in group B. The difference in tumor size between the two groups before and after PTCD was statistically significant (P 0.05). The average stent patency times in groups A and B were 3.55 ± 0.76 months and 8.76 ± 1.85 months, respectively (P 0.05). The average survival times in groups A and B were 133.5 ± 27.8 days and 252.5 ± 114.5 days, respectively (P 0.05). There was no statistically significant difference in the incidence of complications between the two groups (P 0.05).Double-strand

A broadband chirped-pulse Fourier transform microwave spectrometer was used to detect the rotational spectra of the products of a chemical reaction in the gas phase from 1-18 GHz under the supersonic expansion condition. In natural abundance, pure rotational energy level transitions of tert-butyl chloride and its isotopologues (13C, 37Cl) were observed and assigned. The rotational spectral parameters (rotational constant, quadrupole coupling constant and centrifugal distortion constant) of these isotopologues were determined. The experimental results are in great agreement with the calculated values of quantum chemistry and the spectral parameters in the literature. The accuracy and the capability for chemical detection of our homemade rotational spectrometer were verified by this experiment.

Mountain-agarwood plays an important role in ethnic medicine in China for its pharmaceutical value. Modern pharmacological researches demonstrated that mountain-agarwood was effective for its anti-myocardial ischemia, antibacterial, anti-inflammatory, antitumor and analgesic effects. Mountain-agarwood derives from the peeled roots, stems or twigs of Syringa pinnatifolia which belongs to Syringa genus. It often depends on the purple substance and fragrance to estimate the formation of mountain-agarwood. However, the mechanism of mountain-agarwood formation has not been reported. To observe the microcosmic change in the process during the formation of mountain-agarwood, this study described the microscopic and histochemical characteristics of mountain-agarwood formation through histochemical staining. Our results showed that a significant difference of the distribution of tyloses existed during mountain-agarwood formation. It was observed that inchoate mountain-agarwood had more starch granules and viable cells than mountain-agarwood formed with high level or low level. The amount of polysaccharide and degree of lignification were increased during the mountain-agarwood formation. The results indicated that the mountain-agarwood, which meets the quality requirements for pharmaceutical use, contained the following characteristics: a large amount of purple tyloses in heartwood; yellow-brown tyloses distributing in heartwood and sapwood which were less in the latter; lignification with high level; a few viable cells; lots of polysaccharide and few starch granules in xylem rays cell. This study is aimed to reveal the change of histochemical characteristics during mountain-agarwood formation, and lay the foundation for exploring the mechanism of mountain-agarwood formation.

Haemaphysalis flava is the vector of several pathogens and has medical and veterinary importance. Transcriptome information of the ovary of H. flava is unavailable and limits understanding of its molecular basis of reproduction. We studied the ovary transcriptome of partially engorged and fully engorged H. flava using high-throughput RNA sequencing technology. A total of 53,025,360 and 57,942,890 clean reads were obtained with 7.95 GB and 8.69 GB clean bases in partially engorged ticks (PETs) and fully engorged ticks (FETs), respectively. The clean reads were assembled into 138,711 unigenes. A total of 72,043 unigenes (51.93%) were annotated and 66,668 unigenes (48.07%) were unknown. A total of 38,487 differentially expressed genes (DEGs) were found between PET and FET with 19,031 upregulated genes and 19,456 downregulated genes. The RNA-seq results were validated by qRT-PCR, including six upregulated genes and three downregulated genes. Some unigenes coding for nutrient transporters, proteases, and protease inhibitors were found and analyzed. This study was the first time to perform the transcriptome sequences of the ovary of partially engorged and fully engorged H. flava. The results can benefit the understanding of the molecular basis of ovary maturation and oogenesis of the H. flava and boost the development of the strategies for control of H. flava.

Chickens represent a specific case in lipid metabolism that liver is the main site of lipid synthesis. As ovipara, their gut microbiota could be strongly influenced by environment and diets after hatching. The aim of this study is to elucidate the linkage of gut microbiota and fat synthesis in broilers. The broilers were subjected to dietary treatments of combined probiotics (Clostridium butyrate4×108cfu/kg,Bifidobacterium2×108cfu/kg,Lactobacillus plantarum2×108cfu/kg andLactococcus faecalis2×108cfu/kg, PB) and guar gum (1 g/kg, GG). The result showed that dietary supplementation of PB and GG changed the cecal microbiota diversity, altered short chain fatty acids (SCFAs) contents, and suppressed lipogenesis in liver and abdominal fat tissues. In intestinal epithelial cells (IECs), acetate, propionate, and butyrate upregulated the expression of glucagon-like peptide-1 (GLP-1) via MAPK pathways, especially via the ERK and p38 MAPK pathways. GLP-1 suppressed lipid accumulation in primary hepatocytes with the involvement of AMPK/ACC signaling. In conclusion, the result suggests that SCFAs-induced GLP-1 secretion links the regulation of gut microbiome on hepatic lipogenesis in chickens.IMPORTANCEIntestinal microbes metabolize SCFAs and stimulate intestinal epithelium L cells to produce GLP-1. Recent evidence showed that GLP-1 reduced fat deposition by reducing appetite and increasing satiety. However, how SCFAs stimulate the secretion of GLP-1 and whether GLP-1 directly affects fat metabolism is not clear. Poultry adipocytes have limited ability to produce fat, and 90% of carcass fat is synthesized in the liver. In addition, large intake of feeds easily leads to fatty liver diseases in chickens. The aim of this study is to investigate how SCFAs mediate secretion of GLP-1 and whether GLP-1 could directly affect hepatic deposition in broiler chickens. The hepatic lipogenesis regulated by the intestinal microbiota of chickens is of great significance to the study of intestinal microbiota and fat deposition in poultry, and this work could provide reference for intestinal microorganism and fat metabolism in mammals and humans.

By using first-principles calculation and quasi-harmonic approximation method, we have systematically investigated the thermal expansion properties of tetragonal phase of PbTiO 3 , focusing on the correlation between the A1(TO) mode and negative thermal expansion (NTE). It is found that volume of the unit cell shows positive thermal expansion in a axis direction, and NTE in c axis direction from 0 K to 900 K. It is also found that the A1(TO) mode is softening when the volume shrinks by the phonon calculation. Calculating of Gruneisen parameters show that the A1(TO) mode makes a main contribution to the NTE, and this vibrational mode is the Pb, Ti and O atoms’ relative motion in c axis direction, which lead to a shrink of the unit cell in this direction. Our calculations clarify the correlation between the phonon mode and NTE of PbTiO 3 in c axis direction at the atomic level, and provide an important theoretical basis for further understanding of the mechanism of the NTE.

The influence of austenitizing temperature on the microstructure and corrosion resistance of 55Cr18Mo1VN high-nitrogen plastic mould steel was investigated. The microstructure, elemental distribution and Cr-depleted zone of different heat-treated samples were investigated by X-ray diffraction, electron probe microanalyzer analysis, and transmission electron microscopy. The corrosion resistance was evaluated using electrochemical measurements, and the analysis of passive film was carried out by X-ray photoelectron spectroscopy. The results indicated that the volume fraction of precipitates decreased, and the homogeneity of elements was improved with increasing austenitizing temperature. The degree of Cr-depleted zone around coarse M 23C6 was severer than that around M 2N, and pitting corrosion initiated preferentially around M 23C6. The corrosion resistance of the samples increased with the austenitizing temperature. With the increase in austenitizing temperature, the passive film was thickened and $$ {\text{Cr}}\left( {\text{III}} \right)_{{{\text{Cr}}_{2} {\text{O}}_{3} }} $$ in the inner layer of passive film was enriched, which enhanced the corrosion resistance of the steel. The higher content of nitrogen in solid solution at higher austenitizing temperature contributed to the increased intensity of CrN and NH3, leading to the increase in pH value in the pit, and promoting the repassivation of 55Cr18Mo1VN steel.

BACKGROUND Hilar cholangiocarcinoma (CC) is a common malignant tumor with high malignancy and poor prognosis. Most patients have lost the opportunity to undergo radical surgery when diagnosed. Although palliative drainage or biliary stent placement is a preferable choice, the tumor cannot be controlled. This study aimed to develop a novel brachytherapy drainage tube for low-dose-rate brachytherapy with an effective drainage, thereby prolonging the survival time of patients. CASE SUMMARY A 54-year-old male patient had undergone choledochal stent implantation due to obstructive jaundice. He was admitted to the hospital because of the recurrence of jaundice. Preoperative imaging and pathological biopsy revealed hilar CC (Bismuth-Corlette type IIIa). First, the patient underwent percutaneous transhepatic cholangial drainage and the symptoms of jaundice gradually relieved. To further treat hilar CC and remove the biliary drainage tube as far as possible, the patient chose to use the novel brachytherapy drainage tube after a multi-disciplinary consultation. After 1 mo of brachytherapy, the re-examination revealed that the obstructive lesions disappeared, and the drainage tube was finally removed. During the following 10 mo of follow-up, the patient's hilar CC did not recur. CONCLUSION The novel brachytherapy drainage tube may be a new choice for patients with unresectable hilar CC.

The relationship between circadian rhythms and mood disorders has been established, circadian dysregulations are believed to exacerbate the severity of mood disorders and vice versa. Although many studies on diurnal changes of clock genes in animal model of depression have been performed from the RNA level, only a few studies have been carried out from the protein level. In this study, we investigated the diurnal changes induced by chronic unpredictable stress (CUS) using various methods, including free-running wheel test, enzyme-linked immunosorbent assay (ELISA) and Western Blotting (WB). Besides, we examined the depression-like behaviors of rats by sucrose preference test (SPT) and forced swim test (FST). We found that CUS induced significant reductions in the quantity of free-running wheel activity and the amplitude of melatonin secretion rhythm. We also found that CUS induced rhythmic disruptions of clock proteins in hippocampus. Furthermore, we found that the amplitude of PER1 in CA1 was positively related to the severity of depression-like behaviors. These results suggest that stress results in both changes in circadian rhythms and in depression-like behaviors and that it is suggested that these changes are related.