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Abstract: The membrane integrity of cells is significant for the safe and effective removal of cyanobacterial cells from drinking water sources. In this paper, cell density counting, cell viability testing, chlorophyll-a determination, extracellular MC-LR monitoring and PCR–DGGE analysis were applied to assess the effects of coagulant dose, shear and floc storage time on the integrity of Microcystis aeruginosa FACHB-905. Results showed that all cells were removed without damage to membrane integrity under the optimum coagulation conditions: coagulant dose 15mg/L AlCl3, rapid mix speed 250r/min, rapid mix time 1min, slow mix speed 20r/min, slow mix time 20min. The coagulant dose and shear did not cause the lysis of cells and ensuing release of MC-LR. But when the flocs were stacked over 6days, the cells lysed and the MC-LR concentration increased above the background level. In addition, the degree of cell breakage without coagulation was higher than the coagulated cells in flocs. Therefore, keeping the flocs safely treated or disposed of on time as well as keeping the cyanobacterial cells integrally removed plays an important part in controlling the harm of blooms to drinking water production. [Copyright &y& Elsevier]

In this study, a method was established for in-situ visualization of metabolite distribution in the rhizome of Paris polyphylla var. yunnanensis. To be specific, through matrix-assisted laser desorption/ionization-mass spectrometry imaging(MALDI-MSI), the spatial locations of steroidal saponins, amino acids, organic acids, phytosterols, phytoecdysones, nucleosides, and esters in rhizome of the medicinal plant were directly analyzed, and six unknown compounds with differential distribution in rhizome tissues were identified. The specific procedure is as follows: preparation of rhizome tissue section, matrix screening and optimization, and MALDI-MSI analysis. The results showed that the steroidal saponins were mainly distributed in the central, amino acids in epidermis and cortex, low-molecular-weight organic acids in central epidermis, phytosterols in the epidermis and lateral cortex, the phytoecdysones in epidermis and cortex, nucleosides(uneven distribution) in epidermis and cortex, growth hormones around the epidermis and cortex, particularly outside the cortex, and esters in cortex with unobvious difference among different tissues. In this study, the spatial distribution of meta-bolites in the rhizome of P. polyphylla var. yunnanensis was characterized for the first time. The result can serve as a reference for identifying and extracting endogenous metabolites of P. polyphylla var. yunnanensis, exploring the synthesis and metabolism mechanisms of the metabolites, and evaluating the quality of medicinal materials.

Objective: To explore the effect of 18-β glycyrrhetinic acid (GA) on the endoplasmic reticulum of nasal epithelial cells in allergic rhinitis (AR) model rats., Methods: Totally 96 Wistar rats were randomly divided into the blank group, the AR model group, the loratadine group, the GA group, 24 in each group. AR models were established by peritoneally injecting ovalbumin (OVA). Morphological scoring was performed. GA at 21. 6 mg/kg was intragastrically administered to rats in the GA group. Nasal mucosal tissues were taken for electron microscopic examinations at the second, fourth, sixth, and tenth week after drug intervention., Results: The overlapping score was 2.10 ± 0.45 in the blank group, 5.10 ± 0.56 in the loratadine group, 5.10 ± 0.56 in the AR model group, 5.20 ± 0.78 in the GA group, showing statistical difference when compared with the blank group (P < 0.01). Results under transmission electron microscope showed that the number of the endoplasmic reticulum increased in the AR model group, with obvious cystic dilatation, a lot of vacuole formation, and degranulation. A large number of free ribosomes could be seen in cytoplasm. With persistent allergen exposure, changes mentioned above was progressively aggravated in the endoplasmic reticulum of nasal mucosal epithelium in the AR model group. But the dilation of endoplasmic reticulum, vacuole formation, and degranulation were relieved in the GA group, and got close to those of the blank group., Conclusion: 18-β GA could improve the expansion, vacuolization, and degranulation of the endoplasmic reticulum of nasal epithelial cells in AR model rats.

Objective: To observe the relationship between inflammatory response and the constituents of islet β cell secretion during stress hyperglycemia (SHG) in critically ill patients, in order to study the impact of inflammatory response on insulin resistance and the secretion function of islet β cells., Methods: According to the state of inflammatory response, 45 critical patients with SHG were divided into two groups: stress and the convalescence period. Twenty five healthy individuals were enrolled as control group. The blood levels of tumour necrosis factor β (TNF-β), blood glucose (BG), and insulin components including proinsulin (PI), immunoreactive insulin (IRI), true insulin (TI), C-peptide (C-P) were measured respectively. The levels of BG, TNF-β, insulin components, insulin resistance index (HOMA-IR) and the secretion index (HOMA-β) were compared among groups. The relationship between TNF-β and BG, insulin components, HOMA-IR, HOMA-β were analyzed., Results: (1)There was no difference in concentrations of TI among stress period, convalescence stage and control group [3.68 (1.57, 7.70), 3.42 (2.41, 7.40), 1.46 (0.35, 4.90) mU/L, all P >0.05], whereas the concentration of BG [(10.04 ± 2.43) mmol/L], TNF-β [13.70 (11.77, 20.00) ng/L], PI [6.20 (3.22, 9.27) pmol/L], IRI [13.45 (9.88, 19.88) mU/L] and C-P [3.01 (2.37, 4.00) μg/L]in stress period were significantly higher than those in the convalescence stage[BG: (6.09 ± 0.84) mmol/L, TNF-β: 11.58 (8.80, 13.22) ng/L,PI: 1.54 (0.36, 11.82) pmol/L, IRI: 10.80 (5.35, 12.60) mU/L, C-P: 2.42 (1.17, 3.56) μg/L] and control group [BG: (4.87 ± 0.56) mmol/L,TNF-β: 9.27 (7.48, 12.16) ng/L, PI: 2.20 (1.88, 4.54) pmol/L, IRI: 5.50 (4.00, 8.00) mU/L, C-P: 1.15 (0.87, 1.76) μg/L, P <0.05 or P <0.01]. (2)The HOMA-IR [5.17 (3.41, 11.51)] in stress period was significantly higher than that in the convalescence[3.24 (1.51, 6.95)] and control group [1.14 (0.81, 1.79), P <0.05 and P<0.01]. The HOMA-β [10.80 (3.72, 31.40)] of isletβ cell in stress period was significantly lower than that in the convalescence [28.42 (6.46, 125.01)] and control group [21.94 (7.77, 62.01), P <0.01 and P <0.05]. (3)There were positive correlations between the concentration of TNF-β and PI, IRI, C-P and HOMA-IR ( r 1=0.292, r 2=0.344, r 3=0.397, r 4=0.324, P <0.05 or P <0.01). There were negative correlation between concentration of TNF-β and HOMA-β ( r =-0.235 , P <0.05) ., Conclusion: The severer the inflammatory response, the higher PI, IRI and C-P, while the secretion of TI is relatively deficient.Inflammatory response could affect insulin resistance and the secretion function of islet βcell during SHG in critically ill patients.