Severe anemia, severe leukopenia, and severe thrombocytopenia of amphotericin B deoxycholate-based induction therapy in patients with HIV-associated talaromycosis: a subgroup analysis of a prospective multicenter cohort study.

BACKGROUND: This study's objective was to investigate the predictors for severe anemia, severe leukopenia, and severe thrombocytopenia when amphotericin B deoxycholate-based induction therapy is used in HIV-infected patients with talaromycosis. METHODS: A total of 170 HIV-infected patients with talaromycosis were enrolled from January 1st, 2019, to September 30th, 2020. RESULTS: Approximately 42.9%, 20.6%, and 10.6% of the enrolled patients developed severe anemia, severe leukopenia, and severe thrombocytopenia, respectively. Baseline hemoglobin level < 100 g/L (OR = 5.846, 95% CI: 2.765 ~ 12.363), serum creatinine level > 73.4 µmol/L (OR = 2.573, 95% CI: 1.157 ~ 5.723), AST/ALT ratio > 1.6 (OR = 2.479, 95% CI: 1.167 ~ 5.266), sodium level ≤ 136 mmol/liter (OR = 4.342, 95% CI: 1.747 ~ 10.789), and a dose of amphotericin B deoxycholate > 0.58 mg/kg/d (OR = 2.504, 95% CI:1.066 ~ 5.882) were observed to be independent risk factors associated with the development of severe anemia. Co-infection with tuberculosis (OR = 3.307, 95% CI: 1.050 ~ 10.420), and platelet level (per 10 × 109 /L) (OR = 0.952, 95% CI: 0.911 ~ 0.996) were shown to be independent risk factors associated with the development of severe leukopenia. Platelet level < 100 × 109 /L (OR = 2.935, 95% CI: 1.075 ~ 8.016) was identified as the independent risk factor associated with the development of severe thrombocytopenia. There was no difference in progression to severe anemia, severe leukopenia, and severe thrombocytopenia between the patients with or without fungal clearance at 2 weeks. 10 mg on the first day of amphotericin B deoxycholate was calculated to be independent risk factors associated with the development of severe anemia (OR = 2.621, 95% CI: 1.107 ~ 6.206). The group receiving a starting amphotericin B dose (10 mg, 20 mg, daily) exhibited the highest fungal clearance rate at 96.3%, which was significantly better than the group receiving a starting amphotericin B dose (5 mg, 10 mg, 20 mg, daily) (60.9%) and the group receiving a starting amphotericin B dose (5 mg, 15 mg, and 25 mg, daily) (62.9%). CONCLUSION: The preceding findings reveal risk factors for severe anemia, severe leukopenia, and severe thrombocytopenia. After treatment with Amphotericin B, these severe adverse events are likely unrelated to fungal clearance at 2 weeks. Starting amphotericin B deoxycholate at a dose of 10 mg on the first day may increase the risk of severe anemia but can lead to earlier fungal clearance. TRIAL REGISTRATION: ChiCTR1900021195. Registered 1 February 2019.

Nanosized drug delivery systems modulate the immunosuppressive microenvironment to improve cancer immunotherapy.

Immunotherapy that activates immune systems for combating cancer has yielded considerable clinical benefits recently. However, the immunosuppressive tumor microenvironment (ITME) is a major hurdle to immunotherapy as it supports tumor to evade immune surveillance. Reversing ITME facilitates the recruitment and activation of antitumor immune cells, thereby promoting immunotherapy. Our group has developed various nanosized drug delivery systems (NDDSs) to modulate ITME with enhanced efficacy and safety. In the review we introduce the ITME-remodeling strategies for improving immunotherapy based on NDDSs including triggering tumor cells to undergo immunogenetic cell death (ICD), applying tumor vaccine, and directly regulating intratumoral immune components (immune cells or cytokines). In order to guide the design of NDDSs for amplified effects of antitumor immunotherapy, the contributions and future directions of this field are also discussed.

Initiating antiretroviral therapy within 2 weeks of anti-Pneumocystis treatment does not increase mortality or AIDS-defining events in patients with HIV-associated moderate to severe Pneumocystis pneumonia: results of a prospective observational multicenter study.

BACKGROUND: The mortality rate remains high among patients with coinfection with Pneumocystis pneumonia (PCP) and HIV. The timing for initiation of antiretroviral therapy (ART) after a diagnosis of moderate to severe PCP remains controversial, however. We therefore designed the present study to determine the optimal timing for ART initiation in AIDS-associated PCP (AIDS/PCP) patients. METHODS: This was a multicenter, observational, prospective clinical trial. Eligible participants were recruited from 14 hospitals in mainland China, and assigned to an Early ART arm (initiation of ART ≤ 14 days after PCP diagnosis) and a Deferred ART arm (initiation of ART > 14 days after PCP diagnosis). The primary outcomes were death and the incidence of AIDS-defining events at week 48. The secondary outcomes were the changes in CD4+ T-cell counts from baseline values at weeks 12, 24, and 48, the virological suppression rate at week 24 and week 48, the rate of development of PCP-associated immune reconstitution inflammatory syndrome (PCP/IRIS), and the rate of adverse events over 48 weeks. RESULTS: The present study was performed using the data of 363 participants, with 169 participants in the Early ART arm, and 194 participants in the Deferred ART arm. Immunological and virological outcomes were found to be similar in both treatment arms. At week 48, there were no significant differences for the incidence of mortality (20 vs. 26, p = 0.860), and AIDS-defining events (17 vs. 26, p = 0.412). Over 48 weeks, the rates of PCP/IRIS (2 vs. 3, p = 1.000), adverse events (70 vs. 72, p = 0.465), and grade 3 or 4 adverse events (28 vs. 34, p = 0.919) did not reach statistical significance. A significant difference observed between two study arms was that 11 participants (55.0%) in the Early ART arm compared to 23 participants (88.5%) in the Deferred ART arm (p = 0.026) succumbed before ART had ever been started. CONCLUSIONS: Early ART initiation results in no increase in mortality, AIDS-defining events, IRIS, adverse events, and immunological or virological outcomes. These results support the early initiation of ART in patients with moderate to severe AIDS/PCP. Clinical trial registration The present trial was registered at Chinese Clinical Trial Registry (ChiCTR1900021195). Registered 1 February 2019, http://www.chictr.org.cn/showproj.aspx?proj=35362 .

Efficacy and Safety of Voriconazole Versus Amphotericin B Deoxycholate Induction Treatment for HIV-Associated Talaromycosis: A Prospective Multicenter Cohort Study in China.

INTRODUCTION: Current guidelines recommend amphotericin B as the preferred drug for induction therapy; however, amphotericin B is not available in certain settings. Induction therapy with amphotericin B deoxycholate or voriconazole has been shown to be an effective treatment for talaromycosis. However, prospective clinical trials comparing these two antifungal drugs are absent from the literature. METHODS: In this open-labeled, multicenter, prospective controlled trial, we enrolled patients at 15 hospitals in China from 2019 to 2020. Participants received induction treatment with either amphotericin B deoxycholate intravenously at a dose of 0.5 to 0.7 mg per kilogram per day or voriconazole at a dose of 6 mg/kg intravenously twice daily for the first day, followed by 4 mg/kg intravenously twice daily for 3 days, and then voriconazole was given either intravenously (4 mg/kg intravenously twice daily) or orally (200 mg twice daily) for the remaining 10 days. The primary outcome was all-cause mortality during 48 weeks after baseline. Secondary outcomes were mortality at week 2 or week 24, clinical resolution of talaromycosis, and fungal clearance at week 2. A propensity score (PS) matching analysis was performed to control confounding factors. RESULTS: We observed no difference in the risk of death at week 2, at week 24, or at week 48 in either the unmatched cohort or the matched cohort. Both in the unmatched and the matched cohorts, logistic regression analysis revealed a significantly lower odds ratio of clinical resolution (OR 0.450, 95% CI 0.291-0.696, p < 0.001; OR 0.443, 95% CI 0.261-0.752, p = 0.003) and fungal clearance (OR 0.514, 95% CI 0.333-0.793, p = 0.003; OR 0.542, 95% CI 0.318-0.923, p = 0.024) in voriconazole users compared to amphotericin B deoxycholate users over the course of 2 weeks. In the induction therapy without ART subgroup patients in the amphotericin B deoxycholate group showed a significantly higher rate of clinical resolution and fungal clearance than those in the voriconazole group (56.1% vs. 30.4%, 95% CI 13.4-36.5, p = 0.000; 63.8% vs. 40.4%, 95% CI 11.1-34.7, p = 0.000), whereas there was no significant difference in clinical resolution and fungal clearance in the induction therapy combined with ART subgroup. CONCLUSIONS: Induction therapy using voriconazole had a similar efficacy, in terms of all-cause mortality rate, to induction therapy using amphotericin B deoxycholate in HIV-infected patients with talaromycosis over a 48-week observation period. Amphotericin B deoxycholate contributed to earlier fungal clearance and earlier clinical resolution of symptoms in the induction therapy without ART subgroup, whereas amphotericin B deoxycholate use did not contribute to a significant difference in clinical resolution and fungal clearance in the induction therapy combination with ART subgroup. TRIAL REGISTRATION: ChiCTR1900021195. Registered 1 February 2019, http://www.chictr.org.cn/showproj.aspx?proj=35362 .

HIV-associated talaromycosis: Does timing of antiretroviral therapy matter?

OBJECTIVES: No current academic data is available with respect to the optimal timing to initiate antiretroviral therapy (ART) in HIV-positive patients with talaromycosis. Our study aimed to evaluate the optimal timing of ART initiation for patients presenting with AIDS-related talaromycosis. METHODS: In this prospective, randomized, open-label multicenter trial, 228 patients from 15 hospitals in China were randomly assigned to an early ART group (initiation of ART within 2 weeks after randomization) and a deferred ART group (initiation of ART 2 weeks after randomization). The primary endpoint was all-cause mortality during the 48 weeks after randomization. RESULTS: We observed a significant difference in mortality between the early ART group and the deferred ART group (2.2% vs. 8.9%, 95%CI: -0.15 to 14.05, p = 0.049). The composite outcome of AIDS-defining events or death in the early ART group was found to be lower than that in the deferred ART group (3.3% vs. 14.9%; 95%CI: 2.93 to 19.23, p = 0.008). CONCLUSIONS: The prognosis of HIV-infected patients with talaromycosis in the early ART group was more favorable than that of patients in the deferred ART group. These results demonstrate that early ART initiation should be considered in HIV-infected patients with talaromycosis .

Progress on active tumor-targeting nano drug delivery systems for improving tumor immunotherapy / 药学学报

In recent years, immunotherapy has made great progress in clinical cancer therapy. However, the poor tumor specificity, low intra-tumoral penetration, and low cellular uptake in the systemic delivery of immunotherapeutic drugs lead to low efficacy and poor safety, limiting the development of immunotherapy. Active tumor-targeting nano drug delivery systems (aNDDS) can enhance the concentration of drugs in target cells through the interaction between surface-conjugated antibodies or ligands and the receptors on target cell membranes, providing a viable strategy for specific and efficient drug delivery. In addition, some specific types of cell membranes with the natural targeting ability have been exploited for the construction of biomimetic nanocarriers to improve the drug delivery efficiency. In view of the many advantages of active tumor-targeting nanocarriers, researchers also have designed a series of aNDDS for promoting antitumor immune responses and proved that they improved the efficacy and safety of immunotherapy. In this review, we summarize the recent progress on aNDDS for improving the tumor immunotherapy and look forward to the main challenges and future directions in this field.

Manganese Stress Adaptation Mechanisms of Bacillus safensis Strain ST7 From Mine Soil.

The mechanism of bacterial adaption to manganese-polluted environments was explored using 50 manganese-tolerant strains of bacteria isolated from soil of the largest manganese mine in China. Efficiency of manganese removal by the isolated strains was investigated using atomic absorption spectrophotometry. Bacillus safensis strain ST7 was the most effective manganese-oxidizing bacteria among the tested isolates, achieving up to 82% removal at a Mn(II) concentration of 2,200 mg/L. Bacteria-mediated manganese oxide precipitates and high motility were observed, and the growth of strain ST7 was inhibited while its biofilm formation was promoted by the presence of Mn(II). In addition, strain ST7 could grow in the presence of high concentrations of Al(III), Cr(VI), and Fe(III). Genome-wide analysis of the gene expression profile of strain ST7 using the RNA-seq method revealed that 2,580 genes were differently expressed under Mn(II) exposure, and there were more downregulated genes (n = 2,021) than upregulated genes (n = 559) induced by Mn stress. KAAS analysis indicated that these differently expressed genes were mainly enriched in material metabolisms, cellular processes, organism systems, and genetic and environmental information processing pathways. A total of twenty-six genes from the transcriptome of strain ST7 were involved in lignocellulosic degradation. Furthermore, after 15 genes were knocked out by homologous recombination technology, it was observed that the transporters, multicopper oxidase, and proteins involved in sporulation and flagellogenesis contributed to the removal of Mn(II) in strain ST7. In summary, B. safensis ST7 adapted to Mn exposure by changing its metabolism, upregulating cation transporters, inhibiting sporulation and flagellogenesis, and activating an alternative stress-related sigB pathway. This bacterial strain could potentially be used to restore soil polluted by multiple heavy metals and is a candidate to support the consolidated bioprocessing community.

MiR-485-3p serves as a biomarker and therapeutic target of Alzheimer's disease via regulating neuronal cell viability and neuroinflammation by targeting AKT3.

BACKGROUND: Numerous microRNAs (miRNAs) have been identified as functional molecules in Alzheimer's disease (AD) pathogenesis. This study aimed to investigate the diagnostic value of microRNA-485-3p (miR-485-3p) in AD patients, evaluate the effect of miR-485-3p on neuronal viability and neuroinflammation, as well as the underlying molecular mechanisms. METHODS: Quantitative Real-Time PCR was used to estimate expression of miR-485-3p and AKT3. A ROC analysis was used to evaluate the diagnostic value of miR-485-3p. The correlation of miR-485-3p with patients' MMSE score and inflammatory response was analyzed. Using Aß-treated SH-SY5Y and BV2 cells models, the effects of miR-485-3p on neuronal proliferation, apoptosis, and neuroinflammation were explored. A luciferase reporter assay was used to confirm the target gene of miR-485-3p in both SH-SY5Y and BV2 cells. RESULTS: Serum miR-485-3p expression was significantly upregulated in AD patients and cell models, which had a high diagnostic accuracy and correlated with MMSE score and inflammatory response in AD patients. The knockdown of miR-485-3p in SH-SY5Y and BV2 cells was found to significantly reverse the effect of Aß treatment on neuronal viability and neuroinflammation. AKT3 was determined as a target of miR-485-3p, which might mediate the biological function of miR-485-3p in AD pathogenesis. CONCLUSION: All the data indicated that increased serum miR-485-3p serves as a diagnostic biomarker in AD patients, and knockdown of miR-485-3p exerts a neuroprotective role by improving neuronal viability and weakening neuroinflammation, which may be mediated by AKT3. This study may provide a novel biomarker and therapeutic target for AD therapy.

Multicentre derivation and validation of a prognostic scoring system for mortality assessment in HIV-infected patients with talaromycosis.

BACKGROUND: Although the widespread use of modern antiretroviral therapy (ART) has reduced the incidence of talaromycosis in people living with HIV, mortality remains as high as 20% in this population, even after appropriate antifungal treatment. OBJECTIVES: The objective of our study was to develop a risk assessment system for HIV-infected patients with comorbid talaromycosis, in order to provide these patients with appropriate, effective and potentially life-saving interventions at an early stage of their illness. PATIENTS/METHODS: This was a multicentre, retrospective cohort study conducted in China. We built a predictive model based on data from 11 hospitals, and a validated model using the data of 1 hospital located in an endemic area. RESULTS: Forward stepwise multivariate statistical calculations indicated that age, aspartate aminotransferase/alanine transaminase ratio and albumin levels, and BUN levels were valid, independent predictors of the risk of death in HIV-infected patients with talaromycosis. Our developed and validated risk scoring system is effective for the identification of HIV-infected patients with talaromycosis at high risk of death at hospital admission (p < .001; AUC = 0.860). In our study, our risk prediction model provided functional and robust discrimination in the validation cohort (p < .001; AUC = 0.793). CONCLUSION: The prognostic scoring system for mortality assessment developed in the present study is an easy-to-use clinical tool designed to accurately assist clinicians in identifying high-risk patients with talaromycosis.

MicroRNA-150 serves as a diagnostic biomarker and is involved in the inflammatory pathogenesis of Parkinson's disease.

BACKGROUND: Dysregulation of microRNAs (miRNAs) has been reported to be involved in the neuroinflammatory pathogenesis of PD. This study aimed to investigate the serum expression of microRNA-150 (miR-150) in Parkinson's disease (PD) patients and further uncover the regulatory effect of miR-150 on neuroinflammation. METHODS: Quantitative Real-Time PCR was used to measure the expression of miR-150. A receiver operating characteristic curve was applied to evaluate the diagnostic value of miR-150. The effect of miR-150 on neuroinflammation was analyzed by examining its correlation with proinflammatory cytokines and gain-of-function experiments in microglia treated with LPS. RESULTS: Serum miR-150 expression was downregulated in PD patients compared with the healthy controls, and served as a candidate diagnostic biomarker for the screening of PD cases. Negative correlation was found between miR-150 levels and the levels of procytokines in PD patients. By the treatment of LPS, microglia BV2 cells had a reduced expression of miR-150, and the enhanced neuroinflammatory responses were inhibited by the overexpression of miR-150. AKT3 was verified as a target of miR-150 in BV2 cells. CONCLUSION: All the data of this study revealed that the decreased serum miR-150 serves as a potential diagnostic biomarker. The methods to increase miR-150 expression may have a beneficial effect in PD via suppressing the neuroinflammation by targeting AKT3.

Author Correction: Co-delivery of docetaxel and silibinin using pH-sensitive micelles improves therapy of metastatic breast cancer.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Highly Selective Enamination of ß-ketoesters Catalyzed by Interlocked [Cu8 ] and [Cu18 ] Nanocages.

Interlocking cages are of great interest due to their fascinating structures and potential applications. However, the interlocking of different cages has not been previously reported. Herein, quadruply interlocked [Cu8 ] and [Cu18 ] nanocages have been constructed and structurally characterized in cationic metal-organic framework {[CuI Cu4 II (XN)4 (PTA)4 (H2 O)4 ]0.5 SO4 ⋅5 H2 O⋅EtOH}n (1). 1 can trap the anionic pollutant CrO4 2- and the radioactive-contaminant simulant ReO4 - with an uptake capacity of 83.2 and 218 mg g-1 , respectively. Catalytic investigations reveal 1 is an efficient heterogeneous catalyst for the enamination of ethyl acetoacetate with aniline and the turnover frequency (TOF) can reach a record value of 4000 h-1 . More importantly, 1 represents the first of a catalyst of enamination to exhibit excellent size selectivity on different substrates. The robust catalyst can be reused at least ten times without obvious loss in catalytic activity.

Water Stable [Tb4] Cluster-Based Metal-Organic Framework as Sensitive and Recyclable Luminescence Sensor of Quercetin.

A novel 3D metal-organic framework (MOF){[Tb3(CBA)2(HCOO)(µ3-OH)4(H2O)]·2H2O·0.5DMF} n (S-1) was synthesized by the solvothermal method. The crystal structure indicates that [Tb4O4] cubane clusters self-assemble into an infinite chain by sharing vertex, which is further linked to adjacent chains through 1,1-cyclobutanedicarboxylic acid ligand (H2CBA), resulting in a honeycomb arrayed framework. S-1 possesses excellent water stability and still retains intact structure after exposure to water for 10 weeks or boiling water for 10 weeks. Interestingly, S-1 acts as a luminescence sensor to selectively and sensitively detect quercetin with the limit of detection (LOD) as low as 0.23 ppm (7.6 × 10-7 M). The relationship between relative luminescence intensity and concentration obeys linear in the range of 0-300 ppm (0-993 µM), which allows quantitative detection of quercetin. Importantly, S-1 can be reused at least six times with almost no change in luminescent intensity. Compared with the high performance liquid chromatography-mass spectrometry (HPLC-MS) method, S-1 was used to determine the content of quercetin in onionskin and apple peel samples with satisfactory results. Furthermore, a portable S-1 test paper is also developed and expected to be applied in practice. To our knowledge, S-1 is the first example of MOFs as luminescent sensor for quercetin.

Wheel-like Ln18 Cluster Organic Frameworks for Magnetic Refrigeration and Conversion of CO2.

Two isostructural 2D MOFs ([Ln7(CDA)6(HCOO)3(µ3-OH)6(H2O)8] n, abbreviated as 1-Gd and 2-Dy) were successfully synthesized under solvothermal conditions. The self-assembly of lanthanide(III) nitrate and 1,1'-cyclopropane-dicarboxylic acid (H2CDA) resulted in wheel-like Ln18 cluster second building units (SBU), which are further linked to six neighboring wheels to generate a 2D ordered honeycomb array. Both 1-Gd and 2-Dy exhibit high thermal stability and decompose above 330 °C. Moreover, they have good solvent stability in ten common solvents and pH stability with pH values from 1 to 13. Magnetic studies reveal that 1-Gd exhibits weak antiferromagnetic coupling between adjacent Gd3+ ions and has a large magnetocaloric effect of 47.30 J kg-1 K-1 (Δ H = 7.0 T at 2 K), while 2-Dy shows ferromagnetic interaction between adjacent Dy3+ ions. Interestingly, 1-Gd and 2-Dy can catalyze the cycloaddition of CO2 to epoxides under mild conditions and can be reused at least five rounds with negligible loss of catalytic performance.

A unique zinc-organic framework constructed through in situ ligand synthesis for conversion of CO2 under mild conditions and as a luminescence sensor for Cr2O72-/CrO42.

A novel zinc-organic framework, {[Zn3(tza)2(µ2-OH)2(H2O)2]·H2O}n (1) (H2tza = 1H-tetrazolate-5-acetic acid), was synthesized through an in situ generated tetrazole ligand under hydrothermal conditions. In compound 1, tza2- ligands and Zn2+ are interlinked to form 2D layers, which are further pillared through µ2-OH groups to generate a 3D framework. Thermogravimetric analysis and powder X-ray diffraction confirm that 1 has high thermal stability, pH stability and solvent stability. Catalytic studies show that 1 exhibits excellent catalytic ability for the cycloaddition of CO2 with epoxides under 50 °C and 0.1 MPa. Importantly, 1 can be reused at least six times. Furthermore, luminescence investigations indicate that 1 can serve as a recyclable luminescence sensor to efficiently detect Cr2O72-/CrO42-, and the detection limit can reach 10-6 mol L-1 and 4 × 10-6 mol L-1, respectively.

Co-delivery of docetaxel and silibinin using pH-sensitive micelles improves therapy of metastatic breast cancer.

Breast cancer is the most vicious killer for women, and tumor metastasis is one of the leading causes of breast cancer therapy failure. In this study, a new pH-sensitive polymer (polyethylene glycol-block-poly[(1,4-butanediol)-diacrylate-ß-N,N-diisopropylethylenediamine], BDP) was synthesized. Based on BDP, docetaxel/silibinin co-delivery micelles (DSMs) was constructed. DSM had a well-defined spherical shape under the transmission electron microscope with average hydrodynamic diameter of 85.3±0.4 nm, and were stable in the bloodstream but could dissociate to release the chemotherapeutic agents in the low pH environment of the endo/lysosomes in the tumor cells. Compared with free drugs, DSM displayed greatly enhanced cellular uptake, higher cytotoxicity and a stronger anti-metastasis effect against mouse breast cancer cell line 4T1. In 4T1 tumor-bearing mice treated with DSM (twice a week for 3 weeks), the inhibition rate on tumor growth and metastasis reached 71.9% and 80.1%, respectively. These results reveal that DSM might be a promising drug delivery system for metastatic breast cancer therapy.

[Preparation, characterization and three way catalytic performance for Pd/CZ/Al2O3 catalyst].

Pd/CZ/Al2O3 catalyst was prepared by impregnating a noble metal solution to the support CZ/Al2O3 which was prefabricated by co-impregnation. The investigation results show that Pd/CZ/Al2O3 has a superior three-way catalytic performance, which is comparable to Pd/CZ for the fresh sample and a better one after thermal ageing. Based on the XRD, BET and TPR characterizations, the internal relationship between catalytic performance, composition and structure was discussed. The relatively high activity after thermal ageing is ascribed to the maintenance of the Strong Metal-Support Interaction (SMSI).

Synergistic effect of palladium and oxygen vacancies in the Pd/perovskite catalysts synthesized by the spc method.

A series of oxygen-deficient perovskite-supported palladium catalysts were prepared by the "solid phase crystallization" (spc) method and investigated with XRD, TPR, TPD, TEM, XPS, BET analysis and CO oxidation. It was found that Pd/perovskite catalysts synthesized by the spc method were more active for CO oxidation than the calcined LaCo0.95 Pd0.05 O3, where Pd dispersed in the solid solution. H2-reducing treatment in the spc method could yield not only high-dispersed fine Pd particles on the perovskite surface but also oxygen-deficient structure. In these perovskite-supported Pd catalysts, oxygen vacancies adsorbed, activated and supplied oxygen to the active Pd sites, where the oxidation occurred with adsorbed CO. The high activities were due to the cooperative action of Pd and oxygen vacancies.

[Screening of mimic epitopes of Trichinella spiralis antigen from phage 12-mer peptide library].

OBJECTIVE: To screen special mimic epitopes of Trichinella spiralis antigen from peptide library for exploring new diagnostic antigens. METHODS: Ts-IgG purified from serum of trichinosis patients was used to screen the phage 12-mer peptide library for 5 rounds. 24 clones were picked out randomly to detect the immunoactivity. The sensitivity and specificity of the 6 clones (T1 - T6) whose A values were higher than others were tested by ELISA. RESULTS: The sensitivity of the clones T1 - T6 was the same with larval antigen of Trichinella spiralis (TsA) (positive rate: 100%, P > 0.05), and there was no difference in specificity between T1 - T6 and TsA (negative rate: 0 - 40%, P > 0.05); T3 and T6 did not react with sera from patients of paragonimiasis, showing higher specificity than TsA (P < 0.05); T6 did not react with sera from patients of schistosomiasis, also showing higher specificity than TsA (P < 0.05). CONCLUSION: The mimic antigenic epitopes of Trichinella spiralis have been successfully obtained by screening phage 12-mer peptide library.

[Preparation method of Pd/Ce0.5Zr0.5O2 three-way catalysts].

1% Pd/Ce0.5Zr0.5O2(CZ) catalysts were prepared by deposition-precipitation (DP), mixing (MIX) and conventional impregnation (IMP) methods, and the effects of the preparation methods on the three-way catalytic behaviors were investigated. Hydrogen temperature-programmed reduction (H2-TPR) and in situ diffuse reflectance infrared fourier transform spectroscopy (DRIFTS) were performed to understand the Pd-support interaction and the three-way catalytic reaction mechanisms. The experiments results reveal that the catalyst prepared by deposition-precipitation (DP) method shows the strongest Pd-support interaction and the best light-off performance. In situ DRIFTS results suggest that there exists alternative route of NOx reduction over Pd-DP catalyst. And it is supposed that Pd-support interaction leads to the difference of reaction mechanism and then the diversity of light-off performances.