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Excessive daytime sleepiness (EDS) is associated with quality of life and all-cause mortality in the end-stage renal disease population. This study aims to identify biomarkers and reveal the underlying mechanisms of EDS in peritoneal dialysis (PD) patients. A total of 48 nondiabetic continuous ambulatory peritoneal dialysis patients were assigned to the EDS group and the non-EDS group according to the Epworth Sleepiness Scale (ESS). Ultra-high-performance liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry (UHPLC-Q-TOF/MS) was used to identify the differential metabolites. Twenty-seven (male/female, 15/12; age, 60.1 ± 16.2 years) PD patients with ESS ≥ 10 were assigned to the EDS group, while twenty-one (male/female, 13/8; age, 57.9 ± 10.1 years) PD patients with ESS < 10 were defined as the non-EDS group. With UHPLC-Q-TOF/MS, 39 metabolites with significant differences between the two groups were found, 9 of which had good correlations with disease severity and were further classified into amino acid, lipid and organic acid metabolism. A total of 103 overlapping target proteins of the differential metabolites and EDS were found. Then, the EDS–metabolite–target network and the protein–protein interaction network were constructed. The metabolomics approach integrated with network pharmacology provides new insights into the early diagnosis and mechanisms of EDS in PD patients. [ABSTRACT FROM AUTHOR]

Mitochondria are a crucial energy source for maintaining neuronal growth and synaptic function. Neurons possess unique morphological characteristics, which make the proper regulation of mitochondrial transport essential for meeting their energy demands. Syntaphilin (SNPH) is capable of specifically targeting the outer membrane of axonal mitochondria, anchoring them to microtubules, and thereby preventing their transport. SNPH also interacts with other mitochondrial proteins to regulate mitochondrial transport. The regulation of mitochondrial transport and anchoring mediated by SNPH is indispensable for axonal growth during neuronal development, maintenance of ATP levels during neuronal synaptic activity, and regeneration of mature neurons following damage. Precise blocking of SNPH may be an effective therapeutic strategy for neurodegenerative diseases and related mental disorders. [ABSTRACT FROM AUTHOR]

The water immersion residual coal tend to happen spontaneous combustion accidents after mining the coal seam. For exploring the oxidative re-ignition properties of high-temperature oxidized water-impregnated long-flame coal, the thermal evolution law toward each pre-oxidized coal soaked in water under varying heating rates (Rh) (5, 10, 15°C/min) has been analyzed by thermogravimetric differential scanning calorimetry (TG-DSC). The findings are as follows: the DTG at the critical temperature (T1) and maximum weight loss temperature (T5) increases, the activation energy (E) decreases, and the heat output increases (maximum 6391J/g) with the rising Rh. The violent oxidated reaction process of coal samples has been delayed as the Rh was 10°C/min. The water-immersed coal sample (I200) contains more free water on the surface, and the maximum (0.45 mW/mg) and total (178.8 J/g) heat absorption of are higher. Oxidation at 200°C and soaking in water (O200I200) reduced the ignition point temperature (minimum 399°C) and E (minimum 18.5 kJ/mol), and increased the total heat release (maximum 323 J/g) making it easier to oxidize and re-ignite. Under the same Rh, the oxidation and combustion traits of each pre-oxidized water-immersed coal (PWIC) remained unchanged. Reducing the Rh can effectively prevent spontaneous combustion of high-temperature oxidized water-soaked coal in shallow-buried and short-distance coal seams in northwest of China. [ABSTRACT FROM AUTHOR]

Residual coal is easily submerged and damaged by groundwater. In the course of mining underlying coal seam, coal belonging to the overlying gob area tends to spontaneously combust during draining water. To explore the effect of micro-functional group transformation in immersed coal on the coal spontaneous combustion (CSC) traits during the low-temperature oxidation process (LTO), the migrant law of special functional groups under varying oxygen concentration (Co) of immersed coal was discussed by infrared spectroscopy. The endothermal and exothermal properties of the function group inside of coal were studied via thermal analysis. It is shown that the higher Co, the more oxygenic function groups on the soaked, and by contrasted with the Co of 18% the 14% has a small increase and the chain length is shortened. The temperature increment together with the Co content determines the functional group content, the pyrolysis process produces some function group. The lower the Co, endothermic coefficient decreases and endothermic temperature increases, the higher the ignition temperature of coal oxy-combustion, the lower the total heat release. And the speed of the oxygen-absorbing weight gain and the conversion of the functional group would be improved followed by the burnout temperature rising. Below 14% Co, the oxidative combustion process will be greatly inhibited. Those findings complement a theoretical basis for preventing long-term water-soaked coal oxidative spontaneous combusting in shallow buried coal seams. [ABSTRACT FROM AUTHOR]

In this study, we conducted a retrospective single-centre study of 1664 singleton pregnancies derived from frozen-thawed blastocyst transfer between January 2017 and December 2018. Analysis showed that there were 596 early pregnancy losses and 1068 ongoing pregnancies. We compared serum HCG (human chorionic gonadotophin) concentrations on days 12, 14, 19, and 21, between the pregnancy loss group and the ongoing pregnancy group. The cut-off level of HCG at each time point was calculated to predict pregnancy outcome. Joint analysis of two single HCG levels taken one week apart was carried out to improve predictive accuracy. The levels of HCG at four time points were significantly lower in the early pregnancy loss group than in the ongoing pregnancy group. According to the area under ROC (receiver operating characteristic curve) curves, all levels of HCG taken at four time points showed good ability to predict the outcome of pregnancy. The joint analysis of two single HCG levels taken one week apart further improved the accuracy of prediction. What is already known on this subject? Multiple studies have shown that the maternal level of serum HCG is the best parameter for predicting the course of pregnancy. What do the results of this study add? The levels of HCG on days 12, 14, 19 and 21 were significantly lower in the early pregnancy loss group than in the group of ongoing pregnancies. According to the area under ROC curves, all levels of HCG taken at four time points showed a good ability to predict the outcome of pregnancy. What are the implications of these findings for clinical practice and/or further research? The joint analysis of two single HCG levels, taken one week apart, further improved the accuracy of prediction. [ABSTRACT FROM AUTHOR]

Two new milbemycin derivatives, milbemycin M (1) and milbemycin N (2), were isolated from the culture of a genetically engineered strain Streptomyces bingchenggensis BCJ60. Their structures were elucidated through the interpretation of NMR and HR-ESI-MS spectroscopic data, as well as comparison with previous reports. The acaricidal and nematicidal activities of them against Tetranychus cinnabarinus and Bursaphelenchus xylophilus were tested. The results showed that compounds 1–2 possessed potent acaricidal and nematocidal activities. [ABSTRACT FROM AUTHOR]

In recent decades, silk fibroin (SF) from silkworm Bombyx mori has been extensively researched and applied in several fields, including: cosmetics, biomedicine and biomaterials. The dissolution and regeneration of SF fibers is the key and prerequisite step for the application of silk protein-based materials. Various solvents and dissolving systems have been reported to dissolve SF fibers. However, the dissolution process directly affects the characteristics of SF and particularly impacts the mechanical properties of the resulting silk biomaterials in subsequent processing. The purpose of this review is to summarize the common solvents, the dissolution methods for silk protein, the properties of the resulting SF protein. The suitable use of SF dissolved in the corresponding solvent was also briefly introduced. Recent applications of SF in various biomaterials are also discussed. [ABSTRACT FROM AUTHOR]

Recurrent spontaneous abortion (RSA) is a common health problem that affects about 5% of fertile women, when it occurs for unknown reasons, it is called unexplained recurrent spontaneous abortion (URSA). Traditional Chinese medicine, such as Bu-Shen-Yi-Qi formula which consists of Dangshen, Tusizi, Baizhu, Baishuo, Duzhong, Sangjisheng, Sugeng, and Tiaohuangqin, has played an invaluable role in the treatment of RSA since ancient times. However, the mechanism of how it takes effect is still not clear. To identify Bu-Shen-Yi-Qi formula could modulate immune condition at maternal-fetal interface via its effect on trophoblasts, HTR-8 of different treatment were co-cultured with peripheral or decidual natural killer (NK) cells, and the receptors such as NKP30 and NKP46 expression on NK cells were measured by flow cytometry (FCM). In this study, we found that herb medium could increase the IDO expression at appropriate concentrations. As an inhibitor of IDO, 1-MT could impair the inhibitory function of trophoblasts on NK cells. Furthermore, Bu-Shen-Yi-Qi formula could enhance the inhibitory function of trophoblasts on NK cells. In conclusion, Bu-Shen-Yi-Qi formula can inhibit NK cytotoxicity by up-regulating IDO expression in trophoblasts and play a role in the treatment of URSA patients. [ABSTRACT FROM AUTHOR]

Two new milbemycin derivatives, 27-methoxylmilbemycin α31 (1) and 27-oxomilbemycin α31 (2), were isolated from the genetically engineered strain Streptomyces bingchenggensis BCJ60. Their structures were determined by 1D NMR, 2D NMR and HR-ESI-MS spectral analysis, and comparison with previous reports. The acaricidal and nematocidal capacities of compounds 1 and 2 were evaluated against Tetranychus cinnabarinus and Bursaphelenchus xylophilus, respectively. The results showed that the two new macrocyclic lactones 1 and 2 possessed potent acaricidal and nematocidal activities. [ABSTRACT FROM AUTHOR]

Two new macrocyclic lactones, 4,25-diethyl-4,25-demethyl-milbemycinβ3(1) and 27-formaldehyde-milbemycinβ14(2), were isolated from a genetically engineered strainStreptomyces bingchenggensisBCJ60. Their structures were determined on the basis of spectroscopic analysis, including 1D and 2D NMR techniques as well as ESI-MS and comparison with data from the literature. The acaricidal and nematocidal capacities of compounds1and2were evaluated againstTetranychus cinnabarinusandBursaphelenchus xylophilus, respectively. The results showed that the two new macrocyclic lactones1and2possessed potent acaricidal and nematocidal activities. [ABSTRACT FROM PUBLISHER]

Background: The associations between rs6887695 and 3′-untranslated region (3′-UTR) single-nucleotide polymorphisms (SNPs) withininterleukin-12B(IL-12B) and autoimmune diseases (ADs) remain controversial and inconclusive. The aim of this study was to evaluate the association betweenIL-12B(3′-UTR A/C and rs6887695 C/G SNPs) and ADs by meta-analysis.Methods: PubMed and EMBASE were exhaustively searched for studies on the association betweenIL-12BSNPs and ADs. Publication bias was examined by a funnel plot and Egger’s test. The robustness of the pooled results was assessed by sensitivity analysis. A fixed- or a random-effects model was applied to calculate the pooled odds ratios (ORs).Results: A total of 34 studies were included in this meta-analysis. The pooled results demonstrated thatIL-12Brs6887695 SNPs were significantly associated with the risk of ADs. However, there was no significant association betweenIL-12B3′-UTR SNPs and ADs. When the studies were stratified by ethnicity, significant association betweenIL-12B3′-UTR SNPs and ADs was observed in both Asian and European population. In addition, allele A within 3′-UTR ofIL-12Bgene was found to be a protective factor for T1DM, but a risk factor for psoriasis.Conclusion:TheIL-12B3′-UTR and rs6887695 SNPs are associated with susceptibility to ADs. [ABSTRACT FROM PUBLISHER]

TaLr35PR5gene was obtained from the gDNA and cDNA of TcLr35 wheat.It was induced byPuccinia triticina, ABA and SA, butTaLr35PR5was induced earlier and its expression level was higher in the incompatible interaction than that in the compatible interaction. In addition, the accumulations ofTaLr35PR5increased stably and showed significant peak challenged byP. triticinaat different growth and development periods of TcLr35 wheat while it maintained similar level and changed little in mock inoculated. Western blottings were conducted to confirm that TaLr35PR5 be induced byP. triticinainfection at the protein expression level. Similar to the expression patterns ofTaLr35PR5at RNA levels, the accumulations of TaLr35PR5 protein were weak in the seedling stage, then increased to the peak and kept constant levels at the mature stage which is consistent with the expression feature ofLr35gene as an adult plant resistance gene. [ABSTRACT FROM AUTHOR]

A simple integrated agarose microchip-based substrate is reported for surface enhanced Raman spectroscopy. The substrate was evaluated for the determination of sodium thiocyanate in milk. The limit of detection was 5 × 10−7grams per milliliter. The microarray design allowed the synchronous processing of many samples. The reported procedure is green and practical for on-site determination of sodium thiocyanate in milk with potential for additional applications. [ABSTRACT FROM AUTHOR]

The characteristic plasticity associated with the deformation of helium bubbles and voids in aluminium under shock compression is investigated by molecular dynamics (MD) simulations. The scenarios indicate that the emission of shear dislocation loops rather than prismatic loops is the mechanism by which helium bubbles and voids collapse. The tendency to favour dislocation nucleation and emission at the trailing side of a void but at both sides of a helium bubble is attributed to the distribution of the resolved shear stress along (111) planes. Under the same loading strength, the resolved shear stress of the leading side of a helium bubble is larger than that of a void due to the internal pressure of the bubble; therefore, the dislocation nucleation at the leading side of a helium bubble is easier than that for a void. Based on the Virial theorem, we find that the locations of the calculated maximum resolved shear stress are in good agreement with the locations of dislocation nucleation. The elastic model clearly shows that the resolved shear stress increases with the internal pressure of the helium bubble but that the location of the maximum resolved shear stress is not affected. The results from the model nicely explain the scenarios that emerged in our MD simulations. The detailed studies of the microscopic mechanism of plastic deformation are important to deeply understand the mechanical properties of irradiated materials. [ABSTRACT FROM AUTHOR]

The phase transition and elastic properties of NaF are investigated by first-principle plane-wave pseudopotential density function theory method, and the thermodynamic properties are also obtained through the quasi-harmonic Debye model. The pressure of about 28 GPa for the phase transition of NaF from the rocksalt (B1) to the cesium chloride (B2) is obtained, which agrees better with the experimental data than previous theoretical results. The elastic constants C 11 and C 12 are found to monotonically increase with pressure; however, C 44 is almost constant with pressure, which agrees well with the experimental results. The dependences of both the relative volume on the pressure and the heat capacity on the temperature and pressure are also investigated. [ABSTRACT FROM PUBLISHER]

Engineering artificial implantable tissues require rapid induction of angiogenesis to meet the significant oxygen and nutrient demands of the cell during tissue repair. In this study, we investigated the role of a Chinese medicine, scutellarin (1), in the tissue engineering scaffold of balb/c mice model. The trial groups of balb/c mice were given an intraperitoneal injection of 1 at 20, 60, and 100 mg/kg per ml, respectively. The implanted samples were retrieved at 1 week and 1 month post transplantation. Angiogenesis response in polyglycolic acid (PGA) scaffold was evaluated by histopathological and immunohistochemical methods. The expression levels of vascular endothelial growth factor (VEGF) were determined by RT-PCR. The results showed that the density of neocapillaries in the PGA was enhanced by basic fibroblast growth factor (bFGF) and 1 at 1 week. At 1 month, only 60 and 100 mg/kg per ml 1 groups continuingly kept significant neocapillaries. The inflammatory cells were significantly less in the 100 mg/kg per ml 1 group in comparison with bFGF group and negative group at 1 week and 1 month. Our results indicated that 1 not only promoted angiogenesis in the PGA scaffold, but also inhibited the host inflammatory response to the xenogenic materials. [ABSTRACT FROM AUTHOR]

Antiglomerular basement membrane (GBM) disease is characteristically described with linear deposition of IgG along GBM. However, the concurrent glomerular immune complex deposition was not rare and might be contributed to the development of anti-GBM disease. In the current series, glomerular immune complexes were identified in 10 of 47 patients who presented with renal-biopsy-proven anti-GBM disease. Six of the 10 patients complicated with a well-documented glomerulonephritis, including two patients with membranous nephropathy, one patient with IgA nephropathy, one patient with membranoproliferative glomerulonephritis, one patient with Schonlein–Henoch nephritis, and one patient with hepatitis B virus associated membranous nephritis. The other four patients had immune complexes with IgG or IgM predominance deposited in glomerular mesangium without a well-documented glomerulonephritis. Clinical and pathological data of patients with immune complex deposition ( n = 10) were compared with those of patients with anti-GBM disease alone ( n = 37). There was no significant difference in age, gender, clinical and pathological manifestations, and renal outcome between the two groups. In general, the association of glomerular immune complexes did not lead to a benign prognosis. Plasma exchange and extensive immunosuppressive therapy should be carried out as soon as possible. The immune complexes deposited in glomeruli might participate in the initiation of anti-GBM disease. [ABSTRACT FROM AUTHOR]

The etherification experiment for FCC light gasoline on transition metals modified H β zeolite was studied in a fixed-bed reactor. The effect of preparation condition of catalyst on the catalyst's activity, stability, and the effect of reaction temperature, methanol/tert-olefin molar ratio, and liquid hour space velocity on the etherification reaction were discussed. The experimental results showed that the different metals modified H β zeolite had different etherification performances. And the conversion of tertiary carbon-olefins of the molybdenum modified H β zeolite, which was loaded 3%, was higher 6.0% than the H β zeolite. The optimal reaction conditions were temperature 70–80°C, liquid hour space velocity 1.0 h -1 and methanol/tert-olefin molar ratio 1.05. The modified H β zeolite catalysts possessed favorable prospect for its higher stability. [ABSTRACT FROM AUTHOR]

Mesangial proliferation and deposition of immunoglobulins and complement components within glomerular mesangium was one of the important pathological features of lupus nephritis. Autoantibodies against human mesangial cells could be detected in the sera of patients with IgA nephropathy (IgAN) and Henoch-Schöenlein nephritis. We speculated that autoantibodies against human glomerular mesangial cells might play a role in the development of lupus nephritis. Objective. To screen autoantibodies against human glomerular mesangial cells in sera from patients with lupus nephritis and to identify their target antigens. Methods. Sera were collected from 96 patients with lupus nephritis as well as 25 patients with IgAN and 20 patients with idiopathic membranous nephropathy (IMN). Cell lysates of in vitro cultured human glomerular mesangial cells were used as antigens in Western-blot analysis to detect autoantibodies against human mesangial cells in sera from patients with lupus nephritis as well as IgAN and IMN. The clinical and pathological significance of the autoantibodies were further investigated. Results. Autoantibodies against human mesangial cells could be detected in 94/96 (97.9%) of the sera from patients with lupus nephritis in Western-blot analysis. Twelve protein bands could be blotted by the sera from patients with lupus nephritis. The prevalence of autoantibodies against human mesangial cells in IgAN was 14/25 (56.0%) and only seven protein bands could be blotted. Five autoantibodies (anti-18, 24, 36, 46, and 91 kD) could be detected only in sera from patients with lupus nephritis. In patients with lupus nephritis, some autoantibodies might have some relationship with gender, hematuria, ANA, anti-dsDNA or anti-ENA antibodies. Conclusions. There are autoantibodies directly against heterogeneous antigens of human glomerular mesangial cells in sera from patients with lupus nephritis, and some of them might be associated with different clinical manifestations. [ABSTRACT FROM AUTHOR]

Six flavonoids, persicogenin ( 1 ), artemetin ( 2 ), luteolin ( 3 ), penduletin ( 4 ), vitexicarpin ( 5 ) and chrysosplenol-D ( 6 ), have been isolated for the first time as new cell cycle inhibitors from Vitex trifolia L., a Chinese folk medicine used to treat cancers, through a bioassay-guided separation procedure. They were identified by spectroscopic methods. The inhibitory effects of 1 – 6 on the proliferation of mammalian cancer cells have been evaluated by the SRB (sulforhodamine B) method and their effects on cell cycle and apoptosis investigated by flow cytometry with the morphological observation under light microscope and by agarose-gel electrophoresis to detect internucleosomal DNA fragmentation. Compounds 1 – 6 inhibited the proliferation of mouse tsFT210 cancer cells with the IC50s (µg?ml -1 ) > 100 (inhibition rate at 100?µg?ml -1 , 47.9%) for 1 , >100 (inhibition rate at 100?µg?ml -1 , 49.6 %) for 2 , 10.7 for 3 , 19.8 for 4 , 0.3 for 5 , and 3.5 for 6 . Flow cytometric investigations for 1 – 6 demonstrated that 1 – 5 mainly inhibited cell cycle at the G2/M phase in a dose-dependent manner with a weak induction of apoptosis on the tsFT210 cells, while 6 induced mainly apoptosis of the same tsFT210 cells also in a dose-dependent manner together with a weak inhibition of the cell cycle at the G0/G1 and G2/M phases, demonstrating that 1 – 6 exert their anti-proliferative effect on tsFT210 cells through inhibiting cell cycle and inducing apoptosis. In contrast to the cell cycle G2/M phase inhibitory main effect on tsFT210 cells, 5 induced mainly apoptosis on human myeloid leukemia K562 cells with a weak inhibition of the cell cycle at the G2/M phase. The present result provides flavonoids 1 – 6 as new cell cycle inhibitors and 1 and 4 as new anticancer flavonoids, which not only provide the first example of cell cycle G2/M phase inhibitory and apoptosis-inducing constituents of V. trifolia L. but also explain the use of Vitex trifolia L. by Chinese people to treat cancers. [ABSTRACT FROM AUTHOR]

A catalyst is provided for the selective hydrogenation of dienes from fluid catalytic cracking gasoline. There are a small quantity of dienes in fluid catalytic cracking gasoline which can deteriorate the quality of fluid catalytic cracking gasoline, as well as make its further process inconvenient. These dienes must be reduced as impurity. In this paper, the nickel supported on alumina selective hydrogenation catalysts modified with magnesium promoter are prepared by impregnation method. The fluid catalytic cracking gasoline ( -1 , the volume ratio of hydrogenation and oil ( V H / V O ) is 10, and the reaction pressure is 1.5 MPa. The temperature of calcination is observed as well, and the optimal one is 1, 000°C [ABSTRACT FROM AUTHOR]

In this paper, the FCC gasoline (75~120 ? C fraction) is investigated and studied on the HZSM-5 type zerolite catalysts modified with zinc nitrate and ammonium dihydrogen phosphate which are prepared by impregnation method. The results show that Zn x –HZSM-5 type zerolite catalysts have a high initial reactivity of aromatization but a rapid deactivation. Compared to Zn x –HZSM-5 type zerolite catalysts, the Zn x –P y –HZSM-5 type zerolite catalysts not only have more stable reactivity of aromatization but a property of isomerization. The Zn (2%)–P(4%)–HZSM-5 has the best performance among them. Also, the reaction operational conditions are observed and studied on the Zn (2%)–P (4%)–HZSM-5 type zerolite catalyst. The results are that the optimal reaction temperature is 430 ? C, the liquid hours space velocity (LHSV) is 1 hr -1 and the reaction pressure is 0.1Mpa. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Antithyroid drugs such as propylthiouracil (PTU) and methimazole (MMI) are common medications in Chinese patients with hyperthyroidism and PTU-induced antineutrophil cytoplasmic antibody (ANCA) positive vasculitis has been reported. The current cross-sectional study aimed to investigate the prevalence and the target antigens of ANCA in Chinese patients with hyperthyroidism pre- and post-antithyroid medication therapy. METHODS: Sera from 216 patients with hyperthyroidism in our hospital were collected from January to July in 2002. Patients were divided into four groups: untreated (n = 34); treated with PTU (n = 62); treated with MMI (n = 77); and treated with both PTU and MMI (n = 43). Indirect immunofluorescence (IIF) assay was used to detect ANCA and ANA. Antigen-specific ELISAs were used to detect antigen specificities. The known antigens included myeloperoxidase (MPO), proteinase 3 (PR3), human leukocyte elastase (HLE), lactoferrin, bactericidal/permeability-increasing protein (BPI), cathepsin G and azurocidin. RESULTS: 33/216 sera were IIF positive, 20 of the 33 samples were ANCA positive, 11 samples were ANA positive, and two samples were both P-ANCA and ANA positive. The prevalence of positive ANCA in patients receiving PTU (14/62, 22.6%) was significantly higher than that of untreated patients (1/34, 2.9%) and patients treated with MMI (0/77, 0), P < 0.017. Of the 22 IIF-ANCA positive samples, 12 (54.5%) sera recognized lactoferrin, seven (31.8%) sera recognized HLE, four sera recognized MPO and azurocidin respectively, three sera recognized PR3 and cathepsin G respectively, and one serum recognized BPI. Six of the 22 (27.3%) patients with ANCA positive had clinical evidence of vasculitis. All patients with MPO-ANCA and two of the three patients with PR3-ANCA had clinical vasculitis. CONCLUSION: PTU is associated with the production of ANCA in patients with hyperthyroidism. PTU-induced ANCA are due to polyclonal activation of B cells. Anti-MPO and anti-PR3 antibodies may associate the occurrence of clinical vasculitis. [ABSTRACT FROM AUTHOR]

Etherification activity of several molecular sieve catalysts for FCC light gasoline was studied in a fixed-bed reactor. H-Beta zeolite was found to be high active than that of others and close to cation exchanged resin catalyst. H-Beta zeolite also showed good activity and selectivity and could not be deactivated easily, and could be easily regenerated after deactivation. In order to further improve etherification activity, the surface acidity and pore structure of zeolite could be modified, by loading different metal oxides. The result showed that the highest conversion of tert-olefin was obtained over Mo/Hβ (1%). The influence of reaction temperature, methanol and tert-olefin molar ratio, reaction pressure, and LHSV on the conversion was investigated. At optimized reaction conditions, tert-olefin conversion of 57.42% had been reached with Mo/Hβ (1%). [ABSTRACT FROM AUTHOR]

OBJECTIVE: To study the clinical and pathological characteristics of patients with microscopic polyangiitis (MPA) with medium artery involvement. METHODS: Hospitalized patients with MPA in recent two years were retrospectively studied. Their clinical and pathological features were compared between patients with and without renal medium artery involvement. RESULTS: Thirty-nine patients had renal pathology confirmed MPA. Nine cases were with medium artery involvement. For the 30 patients without medium artery involvement, 24/30 had crescentic glomerulonephritis and 11/30 also had focal segmental glomerular fibrinoid necrosis; clinically, 21/30 patients were pANCA/MPO-ANCA positive, 26/30 had acute renal failure with an average duration of 14 weeks before MPA was diagnosed, eight cases achieved complete remission after intensive immunosuppressive therapy. Nine MPA patients had medium artery involvement, manifested as segmental fibrinoid necrosis of major branch of arcuate artery, glomerulus ischemia was predominant, but crescentic lesions were mild, none of them reached crescentic glomerulonephritis. Five of the nine were pANCA/MPO-ANCA positive, eight out of the nine patients had acute renal failure with an average duration of eight weeks before diagnosed, seven of the nine achieved complete remission after intensive immunosuppressive therapy. In comparison, MPA with medium artery involvement had a shorter duration (p < 0.05), less crescentic glomerulonephritis in patients with acute renal failure (p<0.01) and more patients achieved complete remission after treatment (p<0.05). CONCLUSION: In present study, about 23% MPA patients had medium artery involvement and their impaired renal function is mainly due to extensive glomerular ischemia. These patients progressed to acute renal failure quicker and responded to therapy better. [ABSTRACT FROM AUTHOR]

In this article, the HZSM-5 type zeolite catalysts modified with zinc nitrate and calcium nitrate are prepared by impregnation method. The FCC gasoline (<75°C fraction) is observed and studied on the modified HZSM-5 type zeolite catalysts. The results are that the Zx-HZSM-5 type zeolite catalysts have a high initial aromatic yield but a rapid deactivation. The Cy-HZSM-5 type zeolite catalysts have a lower aromatic yield and a familiar deactivation comparing to Zx-HZSM-5. The HZSM-5 type zeolite catalysts modified with bimetal zinc nitrate and calcium nitrate have a rather low initial aromatic yield but a long catalyst life; among them, the C3.5Z2.0HZSM-5 has the best performance. And also, the C3.5Z2.0HZSM-5 type zeolite catalyst has demonstrated good regenerated performance. After regenerated three times, the catalyst still has a good stability. The reaction operational conditions are also observed and studied. The results are that the optimal reaction temperature is 450–490°C, the liquid hours space velocity (LHSV) is 1 h-1 and the reaction pressure is 0.1 MPa. [ABSTRACT FROM AUTHOR]