A molecular sieve with ultrafast adsorption kinetics for propylene separation.

The design of molecular sieves is vital for gas separation, but it suffers from a long-standing issue of slow adsorption kinetics due to the intrinsic contradiction between molecular sieving and diffusion within restricted nanopores. We report a molecular sieve ZU-609 with local sieving channels that feature molecular sieving gates and rapid diffusion channels. The precise cross-sectional cutoff of molecular sieving gates enables the exclusion of propane from propylene. The coexisting large channels constituted by sulfonic anions and helically arranged metal-organic architectures allow the fast adsorption kinetics of propylene, and the measured propylene diffusion coefficient in ZU-609 is one to two orders of magnitude higher than previous molecular sieves. Propylene with 99.9% purity is obtained through breakthrough experiments with a productivity of 32.2 L kg-1.

Carboxylated Hexagonal Boron Nitride/Graphene Configuration for Electrosynthesis of High-Concentration Neutral Hydrogen Peroxide.

The electrosynthesis of hydrogen peroxide (H2 O2 ) via two-electron (2e- ) oxygen (O2 ) reduction reaction (ORR) has great potential to replace the traditional energy-intensive anthraquinone process, but the design of low-cost and highly active and selective catalysts is greatly challenging for the long-term H2 O2 production under industrial relevant current density, especially under neutral electrolytes. To address this issue, this work constructed a carboxylated hexagonal boron nitride/graphene (h-BN/G) heterojunction on the commercial activated carbon through the coupling of B, N co-doping with surface oxygen groups functionalization. The champion catalyst exhibited a high 2e- ORR selectivity (>95 %), production rate (up to 13.4 mol g-1 h-1 ), and Faradaic efficiency (FE, >95 %). The long-term H2 O2 production under the high current density of 100 mA cm-2 caused the cumulative concentration as high as 2.1 wt %. The combination of in situ Raman spectra and theoretical calculation indicated that the carboxylated h-BN/G configuration promotes the adsorption of O2 and the stabilization of the key intermediates, allowing a low energy barrier for the rate-determining step of HOOH* release from the active site and thus improving the 2e- ORR performance. The fast dye degradation by using this electrochemical synthesized H2 O2 further illustrated the promising practical application.

Characterization of Mu-Like Yersinia Phages Exhibiting Temperature Dependent Infection.

Yersinia pestis is the etiological agent of plague. Marmota himalayana of the Qinghai-Tibetan plateau is the primary host of flea-borne Y. pestis. This study is the report of isolation of Mu-like bacteriophages of Y. pestis from M. himalayana. The isolation and characterization of four Mu-like phages of Y. pestis were reported, which were named as vB_YpM_3, vB_YpM_5, vB_YpM_6, and vB_YpM_23 according to their morphology. Comparative genome analysis revealed that vB_YpM_3, vB_YpM_5, vB_YpM_6, and vB_YpM_23 are phylogenetically closest to Escherichia coli phages Mu, D108 and Shigella flexneri phage SfMu. The role of LPS core structure of Y. pestis in the phages' receptor was pinpointed. All the phages exhibit "temperature dependent infection," which is independent of the growth temperature of the host bacteria and dependent of the temperature of phage infection. The phages lyse the host bacteria at 37°C, but enter the lysogenic cycle and become prophages in the chromosome of the host bacteria at 26°C. IMPORTANCE Mu-like bacteriophages of Y. pestis were isolated from M. himalayana of the Qinghai-Tibetan plateau in China. These bacteriophages have a unique temperature dependent life cycle, follow a lytic cycle at the temperature of warm-blooded mammals (37°Ð¡), and enter the lysogenic cycle at the temperature of its flea-vector (26°Ð¡). A switch from the lysogenic to the lytic cycle occurred when lysogenic bacteria were incubated from lower temperature to higher temperature (initially incubating at 26°C and shifting to 37°C). It is speculated that the temperature dependent lifestyle of bacteriophages may affect the population dynamics and pathogenicity of Y. pestis.

Pyrethroids exposure alters the community and function of the internal microbiota in Aedes albopictus.

Large amounts of insecticides bring selection pressure and then develop insecticide resistance in Aedes albopictus. This study demonstrated for the first time the effect of pyrethroid exposure on the internal microbiota in Ae. albopictus. 36, 48, 57 strains of virgin adult Ae. albopictus were exposed to the pyrethroids deltamethrin (Dme group), ß-cypermethrin (Bcy group), and cis-permethrin (Cper group), respectively, with n-hexane exposure (Hex group) as the controls (n = 36). The internal microbiota community and functions were analyzed based on the metagenomic analysis. The analysis of similarity (ANOSIM) results showed that the Hex/Bcy (p = 0.001), Hex/Cper (p = 0.006), Hex/Dme (p = 0.001) groups were well separated, and the internal microbes of Ae. albopictus vary in the composition and functions depending on the type of pyrethroid insecticide they are applied. Four short chain fatty acid-producing genera, Butyricimonas, Prevotellaceae, Anaerococcus, Pseudorhodobacter were specifically absent in the pyrethroid-exposed mosquitoes. Morganella and Streptomyces were significantly enriched in cis-permethrin-exposed mosquitoes. Wolbachia and Chryseobacterium showed significant enrichment in ß-cypermethrin-exposed mosquitoes. Pseudomonas was significantly abundant in deltamethrin-exposed mosquitoes. The significant proliferation of these bacteria may be closely related to insecticide metabolism. Our study recapitulated a specifically enhanced metabolic networks relevant to the exposure to cis-permethrin and ß-cypermethrin, respectively. Benzaldehyde dehydrogenase (EC 1.2.1.28), key enzyme in aromatic compounds metabolism, was detected enhanced in cis-permethrin and ß-cypermethrin exposed mosquitoes. The internal microbiota metabolism of aromatic compounds may be important influencing factors for pyrethroid resistance. Future work will be needed to elucidate the specific mechanisms by which mosquito microbiota influences host resistance and vector ability.

Sensitive and rapid detection of Culex pipiens and Aedes albopictus.

Background: Culex pipiens and Aedes albopictus are closely related to human life, and transmit a variety of viruses, causing serious harm to human health. Cytochrome c oxidase I (COI) gene has been selected as a marker gene for studying phylogeny and molecular evolution of species and is also an effective molecular marker for studying the evolutionary mechanism and systematic reconstruction of diptera insects. Methods: A loop-mediated isothermal amplification (LAMP) method for the rapid and sensitive detection of Cx. pipiens and Ae. albopictus were first described in this study. The experimental results were verified by real-time PCR. Results: Our study showed the lower limit of sample concentration that can be detected by LAMP method is 0.5 pg/µl within 20 min for Cx. pipiens, and 1 pg/µl within 20 min for Ae. albopictus, which were more sensitive than PCR method. Validation tests with field samples showed LAMP method had good specificity and sensitivity and could identify the target species quickly and accurately. Conclusion: The LAMP method developed in this study allowed the rapid and sensitive detection of Cx. pipiens and Ae. albopictus, which will be expected to be used for mass screening in batches of the field.

Hemorrhagic fever with renal syndrome caused by destruction of residential area of rodent in a construction site: epidemiological investigation.

BACKGROUND: An outbreak of hemorrhagic fever with renal syndrome (HFRS), caused by a Hantavirus, affected nine adult males in the southwest area of Xi'an in November 2020 was analyzed in this study. METHODS: Clinical and epidemiological data of HFRS patients in this outbreak were retrospectively analyzed. The whole genome of a hantavirus named 201120HV03xa (hv03xa for short) isolated from Apodemus agrarius captured in the construction site was sequenced and analyzed. In addition, nine HFRS patients were monitored for the IgG antibody against the HV N protein at 6 and 12 months, respectively. RESULTS: In this study, inhalation of aerosolized excreta and contaminated food may be the main source of infection. Genome analysis and phylogenetic analysis showed that hv03xa is a reassortment strain of HTNV, having an S segment related to A16 of HTN 4, an M segment related to Q37 and Q10 of HTN 4, and an L segment related to prototype strain 76-118 of HTN 7. Potential recombination was detected in the S segment of hv03xa strain. The anti-HV-IgG level of all the patients persist for at least one year after infection. CONCLUSIONS: This report documented an HFRS outbreak in Xi'an, China, which provided the basic data for epidemiological surveillance of endemic HTNV infection and facilitated to predict disease risk and implement prevention measures.

Identification and characterization of P2-like bacteriophages of Yersinia pestis.

Yersinia pestis is the cause of plague, historically known as the "Black Death". Marmota himalayana in the Qinghai-Tibet Plateau (QTP) natural plague focus is the primary host in China. Although several phages originating from Y. pestis have been characterized. This is the first report of isolation of P2-like phages of Y. pestis from M. himalayana. In this study, the isolation and characterization of three P2-like phages of Y. pestis were reported, which were named as vB_YpM_22, vB_YpM_46 and vB_YpM_50. Comparative genome analysis revealed that vB_YpM_22, vB_YpM_46 and vB_YpM_50 are members of the nonlambdoid P2 family, and are highly similar and collinear with enterobacteriophage P2, plague diagnostic phage L-413C and enterobacteriophage fiAA91-ss. The role of LPS core structure of Y. pestis in the phages' receptor was pinpointed. The findings of this study contribute an advance in our current knowledge of Y. pestis phages and will also play a key role in understanding the evolution of Y. pestis phages.

Evaluation of Phage Therapy for Pulmonary Infection of Mouse by Liquid Aerosol-Exposure Pseudomonas aeruginosa.

BACKGROUND: Pseudomonas aeruginosa is an important nosocomial infectious bacterium, more and more multidrug resistant P. aeruginosa have been isolated and posed severe challenges to clinical antibiotic treatment, bringing additional morbidity, mortality, and economic burden. Bacteriophages can lyse bacteria specificity and are feasible alternatives to antibiotics. METHODS: A Pseudomonas aeruginosa-infecting phage vB_PaeP_PA01EW was isolated. Phage plaque assays, transmission electron microscopy, host-range determination, infection assay analyses, whole-genome sequencing and annotation were performed for the phage. Mice pneumonia model using liquid aerosol-exposure Pseudomonas aeruginosa was established, and phage therapy was evaluated. RESULTS: vB_PaeP_PA01EW belongs to the family Podoviridae according to transmission electron microscopy and was identified as a Luz24likevirus according to the genome analysis. For the phage therapy, compared with the bacteria-infected group, the phage-rescue group has some characteristics. First, adventitial edema and diffuse infiltration of inflammatory cells in tissues were alleviated, Second, bronchial epithelial cell proliferation was reduced. Third, the bacterial burden was significantly decreased. CONCLUSION: This study provided data support and theoretical basis for the clinical application of bacteriophages. It has important guiding significance and reference value for the application of bacteriophage therapy of other pathogenic bacteria.

On fuzzy ideals of BL-algebras.

In this paper we investigate further properties of fuzzy ideals of a BL-algebra. The notions of fuzzy prime ideals, fuzzy irreducible ideals, and fuzzy Gödel ideals of a BL-algebra are introduced and their several properties are investigated. We give a procedure to generate a fuzzy ideal by a fuzzy set. We prove that every fuzzy irreducible ideal is a fuzzy prime ideal but a fuzzy prime ideal may not be a fuzzy irreducible ideal and prove that a fuzzy prime ideal ω is a fuzzy irreducible ideal if and only if ω(0) = 1 and |Im(ω)| = 2. We give the Krull-Stone representation theorem of fuzzy ideals in BL-algebras. Furthermore, we prove that the lattice of all fuzzy ideals of a BL-algebra is a complete distributive lattice. Finally, it is proved that every fuzzy Boolean ideal is a fuzzy Gödel ideal, but the converse implication is not true.

[A relationship between cyclooxygenase-2 expression and tumor angiogenesis in experimental rat liver carcinogenesis].

OBJECTIVE: To explore the relationship between the expression of cyclooxygenase-2 (COX-2) and angiogenesis in hepatocellular carcinoma. METHODS: Forty Wistar rats were divided into two groups: a model group (30 rats) and a normal group (10 rats). Hepatocellular carcinoma was induced with 0.01% diethylnitrosamine (DEN) in the model group rats. The rats were sacrificed in batches at the 6th, 12th and 18th week of the experiment. Histological sections of liver tissues were made using routine methods. The expressions of COX-2, VEGF, VEGFR-2/KDR, and MMP-2 protein in the liver tissues were evaluated using immunohistochemical methods. RESULTS: In liver sections from the model group there were marked pathological changes (steatosis, cell infiltration, cirrhosis and liver cancer). The expressions of VEGF, VEGFR-2/KDR, and MMP-2 in those liver tissues were remarkably increased during the hepatocellular carcinogenesis. Microvessel density (MVD) was also obviously raised during the process of the cancer development. There was a direct correlation between the MVD and VEGF/KDR/MMP-2 (r=0.858, 0.788, 0.684, respectively; all P less than 0.01). There was also a direct correlation between the COX-2 and VEGF/KDR/MMP-2/MVD (r=0.771, 0.599, 0.690, 0.788, respectively; all P < 0.01). CONCLUSION: COX-2 can promote tumor angiogenesis during rat hepatocellular carcinogenesis. This may be one of the mechanisms in which COX-2 promotes carcinomas.

A relationship between cyclooxygenase-2 expression and tumor angiogenesis in experimental rat liver carcinogenesis / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To explore the relationship between the expression of cyclooxygenase-2 (COX-2) and angiogenesis in hepatocellular carcinoma.</p><p><b>METHODS</b>Forty Wistar rats were divided into two groups: a model group (30 rats) and a normal group (10 rats). Hepatocellular carcinoma was induced with 0.01% diethylnitrosamine (DEN) in the model group rats. The rats were sacrificed in batches at the 6th, 12th and 18th week of the experiment. Histological sections of liver tissues were made using routine methods. The expressions of COX-2, VEGF, VEGFR-2/KDR, and MMP-2 protein in the liver tissues were evaluated using immunohistochemical methods.</p><p><b>RESULTS</b>In liver sections from the model group there were marked pathological changes (steatosis, cell infiltration, cirrhosis and liver cancer). The expressions of VEGF, VEGFR-2/KDR, and MMP-2 in those liver tissues were remarkably increased during the hepatocellular carcinogenesis. Microvessel density (MVD) was also obviously raised during the process of the cancer development. There was a direct correlation between the MVD and VEGF/KDR/MMP-2 (r=0.858, 0.788, 0.684, respectively; all P less than 0.01). There was also a direct correlation between the COX-2 and VEGF/KDR/MMP-2/MVD (r=0.771, 0.599, 0.690, 0.788, respectively; all P < 0.01).</p><p><b>CONCLUSION</b>COX-2 can promote tumor angiogenesis during rat hepatocellular carcinogenesis. This may be one of the mechanisms in which COX-2 promotes carcinomas.</p>

[Induction of uridine 5'-diphosphate-glucuronosyltransferase gene expression by sulforaphane and its mechanism: experimental study in human colon cancel cells].

OBJECTIVE: To study the induction of expression of uridine 5'-diphosphate (UDP)-glucuronosyltransferase (UGT) 1A in colon cancer cells by sulforaphane (SFN) and its possible mechanism. METHODS: Human colon cancer cells of the line Caco-2 were cultured and added with SFN of different terminal concentrations, all below the concentration of IC(50). RT-PCR was used to examine the expression of UGT1A mRNA induced by SFN. Western blotting was used to detect the expression of UGT1A protein. The glucuronidation rate of N-hydroxy-PhIP was measured by high performance liquid chromatography (HPLC). The nuclear localization of transcription factor Nrf2 was observed by confocal laser microscopy. RESULTS: (1) Expression of UGT1A mRNA was observed in the Cac0-2 cells induced by SFN of the concentrations of 10 micromol/L approximately 35 micromol/L in a dose-independent manner (P < 0.05). Sulforaphane of the concentration of 25 micromol/L induced the UGT1A mRNA expression time-dependently. The levels of UGT1A1, UGT1A8, and UGT1A10 mRNA expression were significantly increased in the cells treated with 25 micromol/L sulforaphane compared to that in the controls (P = 0.006, P = 0.017, and P = 0.008 respectively). (2) The UGT1A protein band intensity increased significantly in the Coco-2 cells treated with sulforaphane of the concentrations 10 micromol/L approximately 30 micromol/L for 24 h in comparison with the control cells. (3) When the microsomes from the untreated Caco-2 cells were incubated with N-hydroxy-PhIP there was a minor HPLC peak at the expected retention time for N-hydroxy-PhIP-N2-glucuronide. This peak was dramatically increased in the sulforaphane-treated cells, suggesting higher activities of glucuronidation of N-hydroxy-PhIP. (4) Cytoplasmic labeling of NF-E2-related factor 2 (Nrf2), a transcription factor, with no nuclear staining was observed in the non-stimulated cells, whereas an intense nuclear labeling was observed in the sulforaphane-treated cells, indicating the induction of nuclear translocation of Nrf2 by sulforaphane. CONCLUSION: (1) Low dose sulforaphane induces the expression of UGT1A, UGT1A1, UGT1A A8, and UGT1A A10 mRNA significantly. These changes are accompanied by an increase in UGT1A1 protein and increase in heterocyclic aromatic amine glucuronidation. (2) The induction of the phase II enzyme activity by SFN occurs at the transcriptional level and is regulated by Nrf2.

Inhibitory effects of antisense oligodeoxynucleotide on expression of vascular endothelia growth factor by human hepatocarcinoma cells.

BACKGROUND: It is widely recognized that the growth of solid tumor depends on angiogenesis. Vascular endothelia growth factor (VEGF) is an endothelial cell-specific mitogen that promotes angiogenesis in solid tumor. Inhibition of angiogenesis is considered a promising approach for cancer therapy, and treatments including administration of antisense drugs and RNA interference for the VEGF gene are geared to the suppression of tumor angiogenesis. METHODS: As a new approach for gene therapy of hepatocellular carcinoma (HCC), four groups of antisense oligodeoxynucleotide (ASODN) (A-Cap, A-AUG, A-UGA and A-Exon-3) were used to block the expression of VEGF, then VEGF mRNA and protein were detected by RT-PCR and Western blot. RESULTS: After treatment with ASODN, the relative VEGF mRNA levels of A-Cap, A-AUG, A-UGA, and A-Exon-3 were decreased significantly to (32+/-9)%, (63+/-1)%, (86+/-3)%, and (70+/-5)%, respectively(F=64.18, P<0.001). The relative VEGF protein levels of A-Cap, A-AUG, A-UGA and A-Exon-3 were decreased significantly to (41+/-5)%, (59+/-3)%, (88+/-7)%, and (79+/-9)% respectively (F=60.64, P<0.001). CONCLUSIONS: Among the four ASODNs, the ASODN for Cap structure showed the strongest inhibitory effect and that for A-UGA, the least (P<0.05 ). The inhibitory effect of ASODN on the expression of VEGF proteins was similar to that of VEGF mRNA expression.

Antineoplastic effects of octreotide on human gallbladder cancer cells in vitro.

AIM: To investigate whether octreotide can inhibit the growth of human gallbladder cancer cells in vitro and to elucidate the antineoplastic mechanism of octreotide in gallbladder cancer. METHODS: A human gallbladder cancer cell line, GBC-SD, was cultured in vitro. The antiproliferative effects of octreotide were examined by means of an MTT assay and a colony forming ability assay. Morphological variation was investigated under scanning electron microscopy and transmission electron microscopy. Cell cycle analysis and apoptosis rate was evaluated by flow cytometry (FCM) after staining by propidium iodide. DNA fragmentation was assayed by agarose gel electrophoresis. Immunohistochemical staining was performed to evaluate the expressions of mutant-type p53 and bcl-2. RESULTS: The growth curve and colony forming ability assay showed significant inhibition of octreotide to the proliferation of GBC-SD cells in culture in a time- and dose-dependent manner. After exposure to octreotide, GBC-SD cells showed typically apoptotic characteristics, including morphological changes of chromatin condensation, vacuolar degeneration, nucleus fragmentation and apoptotic body formation. In FCM profile apoptotic cells showed increased sub-G(1) peaks in the octreotide group, significantly higher than the control group (P=0.013). There was also an augmentation in the cell proportion of G(0)/G(1) phase (P=0.015), while the proportion of S phase and G(2)/M phase remained unchanged (P=0.057 and P=0.280, respectively). DNA agarose gel electrophoresis displayed a ladder after exposure to 1 000 nmol/L octreotide. After being treated with octreotide, the expressions of both mutant-type p53 and bcl-2 decreased considering the percentage of positive cells (P<0.05). CONCLUSION: Octreotide has a negative action to the proliferation of GBC-SD cells, and the mechanism may be related to cytostatic and cytotoxic effects. The reduction of mutant-type p53 and bcl-2 expressions may be associated with the apoptosis induced by octreotide.