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Jian Qu,1,2 Ting-Ting Qi,1,2 Qiang Qu,3,4 Wen-Ming Long,5 Ying Chen,6 Yue Luo,7 Ying Wang1,2 1Department of Pharmacy, The Second Xiangya Hospital, Central South University, Changsha, 410011, People’s Republic of China; 2Institute of Clinical Pharmacy, Central South University, Changsha, 410011, People’s Republic of China; 3Department of Pharmacy, Xiangya Hospital, Central South University, Changsha, 410078, People’s Republic of China; 4National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, 410078, People’s Republic of China; 5Department of Pharmacy, Jingzhou District, Second People’s Hospital of Huaihua City, Huaihua, 418400, People’s Republic of China; 6Department of Pharmacy, Wuhan University, Renmin Hospital, Wuhan, 430060, People’s Republic of China; 7Department of Pharmacy, The People’s Hospital of Liuyang, Liuyang, 410300, People’s Republic of ChinaCorrespondence: Ying Wang, Department of Pharmacy, The Second Xiangya Hospital, Central South University, Institute of Clinical Pharmacy, Central South University, No. 139 Middle Renmin Road, Changsha, 410011, People’s Republic of China, Tel +86-15173198700, Fax +86-731-85292072, Email wangying5211@csu.edu.cnBackground: The increasing prevalence of carbapenem-resistant Gram-negative bacteria (CR-GNB) represents a global healthcare crisis. This study explored the efficacy and safety of Polymyxin B (PMB)-based regimens and factors influencing their effectiveness.Methods: Patients with CR-GNB infections treated with PMB for more than three days were enrolled in this retrospective study from 1st June 2018 to 30th April 2020. Data were collected on patient characteristics, bacterial culture, and drug-sensitivity test results; anti-infection treatment regimens, particularly details of PMB use; and adverse drug reactions. Clinical and microbiological efficacy, mortality, and safety of PMB-based regimens in CR-GNB infected patients were evaluated. Univariate analysis and multivariate logistic regression analyses were used to assess factors influencing efficacy and mortality.Results: A total of 373 CR-GNB strains were cultured from 268 patients. About 41.04% of patients used PMB loading dose of 1.01 (0.84– 1.69) mg/kg. Maintenance dose was 0.85 (0.82– 1.00) mg/kg q12h. The clinical efficacy rate was 36.57% (98/268), the total bacterial clearance rate of PMB was 39.42%, and the all-cause mortality rate was 33.96%. The adverse drug reaction rate was 19.58%, among which the incidence of renal toxicity was highest (8.21%). Multivariate logistic regression analysis showed that clinical efficacy, bacterial clearance rate, and all-cause mortality were associated with patient-related facts, including mechanical ventilation use, underlying diseases (such as respiratory disease), the type and site of CR-GNB infection, and PMB administration timing and loading dose.Conclusion: PMB is a relatively safe and effective antibiotic drug for treatment of critically ill patients with CR-GNB infection; however, PMB use should be subject to guidelines recommendations for early administration, loading administration, and adequate administration, which could help to improve the clinical efficacy, microbiological efficacy, and mortality.Keywords: polymyxin B, carbapenem-resistant Gram-negative bacteria, clinical efficacy, bacterial elimination, mortality, adverse effect

Purpose: Carbapenem-resistant organisms (CROs) pose great challenges for clinical treatment. Polymyxin B (PMB) is one of the “last resort” choices of CRO infections. We explored the possible factors affecting PMB efficacy. Methods: This retrospective study involved CRO infected patients treated with PMB for ≥72 h. The endpoint indicator was clinical efficacy. We compared the characteristics (demographics, pathogenic bacteria, PMB treatment) between patients who had “clinical success” (CS) and “clinical failure” (CF).Results: A total of 192 patients were enrolled: 110 in the CS group and 82 in the CF group. The total cumulative dose for the CS group was higher than the CF group [1100 (700–1443.75) vs. 800 (500–1112.5) mg; P = 0.001]. Treatment duration in the CS group was longer than the CF group [11 (8–14) vs. 8 (6–11) days; P < 0.000]. Multivariate logistic regression analysis showed mechanical ventilation, vasoactive agents, multiple-site infection, and total cumulative dose to be independently associated with clinical efficacy. Cox survival analysis for 30-day mortality also showed that the use of vasoactive agents and the total cumulative dose of PMB could influence survival time and mortality rate independently.Conclusion: PMB had good efficacy and a low prevalence of adverse reactions. The total cumulative dose，duration of PMB treatment, mechanical ventilation, vasoactive agents, and multiple-site infection were factors associated with the clinical efficacy of PMB.

Aroma compositions of Chinese Daohuaxiang liquors, including five kinds of commercial liquors and three kinds of base liquors, were extracted by solid phase microextraction using a sol–gel divinylbenzene/hydroxy-terminated silicone oil fibre. The effectiveness of the fibre was evaluated in comparison with commercial fibres and liquid–liquid extraction. After identification by GC–MS and GC–O, the compounds were accurately quantified by GC–FID using internal standards. Wide linear ranges, low limits of detection, satisfactory precision and recoveries were achieved. A total of 57 volatile compounds were detected and 28 of them were quantified. Most of them were common in these liquors but differed in terms of their relative amounts. Thirteen out of the 28 compounds had odour activity values greater than 1 in all of the liquors, and are suggested to be the key aroma-contributing substances of Daohuaxiang liquors. Besides, the differences among different aroma types and kinds of Daohuaxiang liquors were also discussed.

Two couples of chiral tri- and tetranuclear Cd(II) clusters, namely [Cd4(S-L1)6]·(ClO4)2 (1) and [Cd4(R-L1)6]·(ClO4)2 (2), and [Cd3(S-L2)4]·(ClO4)2 (3) and [Cd3(R-L2)4]·(ClO4)2 (4) (L1 = 1-(1-(2-pyridine)-ethylimino)-2-naphtho, L2 = 2-(1-(2-pyridine)-ethylimino)-5-bromo-6-methoxy-pheno) have been synthesized via the solution reaction of chiral Schiff-base ligands with Cd(ClO4)2·6H2O, and characterized by single-crystal X-ray analyses, IR and circular dichroism (CD) spectra. Complexes 1 and 2 are a couple of tetranuclear Cd(II) complex enantiomers crystallized in the chiral space group P4222, and 3 and 4 are also a couple of trinuclear Cd(II) complex enantiomers crystallized in another chiral space group P21. The CD measurements further confirmed that 1–2, and 3–4 are a pair of enantiomers with Cotton effects of the opposite sign at the same wavelengths, respectively. The strong solid-state fluorescence emissions were observed at around 465 nm for 1 and 2, and 485 nm for 3 and 4, respectively. Furthermore, complex 3 exhibits a ferroelectric behavior related to the polar point group C2.

Three new letrozole complexes {[Cu(Le)4Cl2]·(H2O)} (1), {[Ni(Le)4Cl2]·(H2O)}(2) and {[Co(Le)4Cl2]·(H2O)} (3) (Le = letrozole = 1-[bis(4-cyanophenyl)methyl]-1, 2, 4-triazole) were obtained from self-assembly of CuCl2, NiCl2·6H2O, and CoCl2·6H2O with medicine letrozole. All compounds were characterized by IR spectroscopy, elemental, single-crystal as well as powder X-ray diffraction, and thermogravimetric analyses. The analyses of the structures indicate that all crystals belong to monoclinic system, space group C2/c, for complex 1 with crystal data a = 34.501(18) A, b = 12.724(7) A, c = 16.116(9) A, β = 114.958(7) °, V = 6414(6) A 3, Z = 4, F(000) = 2660, R1 = 0.0668, wR2 = 0.1574; for complex 2, a = 34.769(6) A, b = 12.7267(18) A, c = 16.046(2) A, β = 115.281(3) °, V = 6420.1(16) A 3, Z = 4, F(000) = 2656, R1 = 0.0510, wR2 = 0.0896; for complex 3, a = 35.063(8) A,b = 12.658(3) A, c = 16.056(4) A, β = 115.387(3) °, V = 6438(2) A3, Z = 4, F(000) = 2652, R1 = 0.0528, wR2 = 0.1205. The local arrangements around central metal atoms (CuII, NiII, and CoII) can be best described as distorted octahedra which are constructed by two chlorine atoms and four monodentate nitrogen atoms from different letrozole ligands. XRD results of 1–3 show that all peaks displayed in the measured patterns at room temperature closely match those in the simulated patterns generated from single-crystal diffraction data, indicating single phases of 1–3 were formed.

Three kinds of magnetite/reduced graphene oxide (MRGO) nanocomposites were prepared by solvothermal, hydrothermal and co-precipitation methods. The as-prepared nanocomposites were characterized and compared by Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, X-ray diffraction and zeta potential. The results showed that MRGO made by different methods differed in surface functional groups, crystal structure, particle sizes, surface morphology and surface charge. Due to their unlike features, these nanocomposites displayed dissimilar performances when they were used to adsorb drugs, dyes and metal ions. The MRGO prepared by the co-precipitation method showed special adsorption ability to negative ions, but those synthesized by the solvothermal method obtained the best extraction ability and reusability to the others and showed a good prospective in magnetic solid-phase extraction. Therefore, it is highly recommended to use the right preparation method before application in order to attain the best extraction performance.

Postsurgical peritoneal adhesion is a major concern in clinical practice which causes significant morbidity and mortality. In this study, we investigated the efficacy of biodegradable and injectable thermosensitive poly(ethylene glycol)-poly(epsilon-caprolactone)-poly(ethylene glycol) (PEG-PCL-PEG) micelles in preventing postsurgical cauterization-induced peritoneal adhesion. The biodegradable PEG-PCL-PEG copolymer could form nano-sized micelles in water, which instantly turned into a non-flowing gel at body temperature due to micellar aggregation. Moreover, a novel sidewall and cecum cauterization rat model was developed and the micelles were assigned for adhesion prevention tests. The PEG-PCL-PEG micelles could be administered by an ordinary syringe and provided unrestricted coverage of the cauterized peritoneum. The micelles instantly formed a gel in situ at body temperature and the formed gel could adhere to the cauterized sites as a durable barrier during critical time of adhesion formation. All rats from the control group (n = 10) developed score 5 adhesion, whereas, eight out of ten rats in the micelle-treated group showed no adhesion at all. Besides, cauterization-induced adhesion formation, adhesiveness and degradation of micelles, remesothelization of peritoneum, and restoration of cauterized tissue were investigated in detail. Our results thus indicated that, it was feasible to use biodegradable and injectable thermosensitive PEG-PCL-PEG micelles for prevention of peritoneal adhesions after surgery.

Proper design and operating optimization of a multilayer belt dryer are involved in a comprehensive understanding of its drying kinetics in the drying course. To investigate the distributions of material moisture content and temperature in granular bed and the profiles of air humidity and temperature in air channel above granular bed, which are decisive to decisions of dryer structure and operating condition, a mathematical model for simultaneous heat and mass transfer process in a multilayer belt dryer, was established. The numerical simulation based on the model was conducted for a practical drying process of garlic slices in an industrial scale dryer and the calculated results were verified by the collected data from the drying process. Based on the drying kinetic data obtained from the further simulations, the proper parameters of dryer structure, namely, length of belt for each layer, height of air channel between layers and number of belt layers, and operating conditions, namely, height of material bed, belt velocity and air velocity, were discussed.