Carbapenem-resistant Klebsiella pneumoniae (CRKP) is emerging as a worldwide public health concern; however, the longterm molecular epidemiological surveillance of clinical CRKP in China is limited. We conducted a retrospective observational study (2008-2018) to assess the prevalence, susceptibility, risk factors and molecular epidemiology of clinical CRKP isolates. We found the prevalence of CRKP increased from 2.5%, 2008 to 15.8%, 2018. CRKP were significantly more frequent among hospitalized patients from ICU, and it was significantly more likely to be isolated from the capital city (Hangzhou) and the patients aged ≥60 years. Additionally, seasons and specimen types were associated with CRKP infections. The main CRKP sequence type (ST) was ST11, and bla KPC-2 was the most prevalent gene variant. Together these data reveal an increasing incidence and resistance trends among CRKP, especially the ST11-bla KPC-2-CRKP, in Zhejiang, during 2008-2018. Our findings are important for hospitals to limit its dissemination and optimize antibiotic administration.

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Emergent resistance to antibiotics among Streptococcus pneumoniae isolates is a severe problem worldwide. Antibiotic resistance profiles for S pneumoniae isolates identified from pediatric patients in mainland China remains to be established. The clinical features, antimicrobial resistance, and multidrug resistance patterns of S pneumoniae were retrospectively analyzed at 10 children's hospitals in mainland China in 2016. Among the collected 6132 S pneumoniae isolates, pneumococcal diseases mainly occurred in children younger than 5 years old (85.1%). The resistance rate of S pneumoniae to clindamycin, erythromycin, tetracycline, and trimethoprim/sulfamethoxazole was 95.8%, 95.2%, 93.6%, and 66.7%, respectively. The resistance rates of S pneumoniae to penicillin were 86.9% and 1.4% in non-meningitis and meningitis isolates, while the proportions of ceftriaxone resistance were 8.2% and 18.1%, respectively. Pneumococcal conjugate vaccine was administered to only 4.1% of patients. Penicillin and ceftriaxone resistance, underling diseases, antibiotic resistant risk factors, and poor prognosis appeared more frequently in invasive pneumococcal diseases. The incidence of multidrug resistance (MDR) was 46.1% in patients with invasive pneumococcal disease which was more than in patients with non-invasive pneumococcal disease (18.3%). Patients with invasive pneumococcal disease usually have several MDR coexistence. S pneumoniae isolates showed high resistance to common antibiotics in mainland China. Penicillin and ceftriaxone resistance rate of invasive streptococcal pneumonia patients were significantly higher than that of non-invasive S pneumoniae patients. Alarmingly, 46.1% of invasive clinical isolates were multidrug resistant, so it is important to continued monitor the resistance of S pneumoniae when protein conjugate vaccine (PCV13) is coming in mainland China.

An aqueous Heck reaction carried out under ultrasonic irradiation at the ambient temperature (25 degrees C) has been shown in this study to afford high yields of corresponding products. It was found that as a catalyst for the reaction palladium forms nanoparticles in-situ, characterized by transmission electron microscopy (TEM) and X-ray powder diffraction (XRD) analyses, and can be recycled. Furthermore, the Heck reaction under such mild and environmentally friendly conditions offers excellent regioselectivity of para- over ortho-substitution in phenyl iodides especially with electron-donating groups.

Cyclocarya paliurus has been widely used as an ingredient in functional foods in China. However, the antioxidant properties of phenolic compounds and the effect of the plant origin remain unclear. The present study evaluated the geographical variation of this plant in term of its phenolic composition and antioxidant activities based on leaf materials collected from five regions. high-performance liquid chromatography (HPLC) analysis showed that there are three major components, quercetin-3-O-glucuronide, kaempferol-3-O-glucuronide, and kaempferol-3-O-rhamnoside, and their contents varied significantly among sampling locations. The investigated phenolic compounds showed substantial antioxidant activities, both in vitro and in vivo, with the highest capacity observed from Wufeng and Jinzhongshan. Correlation analysis revealed that quercetin and kaempferol glycosides might be responsible for the antioxidant activities. Our results indicate the importance of geographic origin, with sunny hours and temperature as the main drivers affecting the accumulation of C. paliurus phenolics and their antioxidant properties.

Antibiotic contamination in agroecosystems may cause serious problems, such as the proliferation of various antibiotic resistant bacteria and the spreading of antibiotic resistance genes (ARGs) in the environment or even to human beings. However, it is unclear whether environmental antibiotics, antibiotic resistant bacteria, and ARGs can directly enter into, or occur in, the endophytic systems of plants exposed to pollutants. In this study, a hydroponic experiment exposing pakchoi (Brassica chinensis L.) to tetracycline, cephalexin, and sulfamethoxazole at 50% minimum inhibitory concentration (MIC) levels and MIC levels, respectively, was conducted to explore plant growth, antibiotic uptake, and the development of antibiotic resistance in endophytic systems. The three antibiotics promoted pakchoi growth at 50% MIC values. Target antibiotics at concentrations ranging from 6.9 to 48.1 µg·kg−1 were detected in the treated vegetables. Additionally, the rates of antibiotic-resistant endophytic bacteria to total cultivable endophytic bacteria significantly increased as the antibiotics accumulated in the plants. The detection and quantification of ARGs indicated that four types, tetX, blaCTX-M, and sul1 and sul2, which correspond to tetracycline, cephalexin, and sulfamethoxazole resistance, respectively, were present in the pakchoi endophytic system and increased with the antibiotic concentrations. The results highlight a potential risk of the development and spread of antibiotic resistance in vegetable endophytic systems.

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The selective response to glucose is possible by using a poly(phenylboronic acid) microgel under a rational design. Such a microgel is made of graphene covalently immobilized in a microgel of poly(4-vinylphenylboronic acid) cross-linked with N,N′-methylenebis(acrylamide). Unlike the microgels reported in previous arts that would undergo volume phase transition in response to both glucose and other monosaccharides, the proposed microgels shrink upon adding glucose, whereas keep unchanged in the size upon adding other monosaccharides (with fructose, galactose, and mannose as models). Although the polysaccharides/glycoproteins (with dextran and Ribonuclease B as models) that contain many glycosyl residues can slightly absorb on the microgel surface and lead to a small impact on glucose-response, it can be addressed by further coating the microgel as a core with a thin nonglucose-responsive poly(N-isopropylacrylamide) gel shell. This selectively glucose-responsive volume phase transition behavior enables “turn-on” photoluminescence detection of glucose in blood serum (a model for complex biosystems).