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Abstract Background 4-Hydroxyphenylacetic acid (4HPAA) is an important building block for synthesizing drugs, agrochemicals, biochemicals, etc. 4HPAA is currently produced exclusively via petrochemical processes and the process is environmentally unfriendly and unsustainable. Microbial cell factory would be an attractive approach for 4HPAA production. Results In the present study, we established a microbial biosynthetic system for the de novo production of 4HPAA from glucose in Escherichia coli. First, we compared different biosynthetic pathways for the production of 4HPAA. The yeast Ehrlich pathway produced the highest level of 4HPAA among these pathways that were evaluated. To increase the pathway efficiency, the yeast Ehrlich pathway enzymes were directedly evolved via error-prone PCR. Two phenylpyruvate decarboxylase ARO10 and phenylacetaldehyde dehydrogenase FeaB variants that outperformed the wild-type enzymes were obtained. These mutations increased the in vitro and in vivo catalytic efficiency for converting 4-hydroxyphenylpyruvate to 4HPAA. A tunable intergenic region (TIGR) sequence was inserted into the two evolved genes to balance their expression. Regulation of TIGR for the evolved pathway enzymes further improved the production of 4HPAA, resulting in a 1.13-fold increase in titer compared with the fusion wild-type pathway. To prevent the toxicity of a heterologous pathway to the cell, an Esa quorum-sensing (QS) circuit with both activating and repressing functions was developed for inducer-free productions of metabolites. The Esa-PesaR activation QS system was used to dynamically control the biosynthetic pathway of 4HPAA in E. coli, which achieved 17.39 ± 0.26 g/L with a molar yield of 23.2% without addition of external inducers, resulting in a 46.4% improvement of the titer compared to the statically controlled pathway. Conclusion We have constructed an E. coli for 4HPAA production with the highest titer to date. This study also demonstrates that the combination of directed evolution of pathway enzymes and dynamic pathway regulation using a QS circuit is a powerful strategy of metabolic engineering for the productions of metabolites.

Abstract We apply the method of QCD sum rules to study the structure X newly observed by the BESIII Collaboration in the $$\phi \eta ^\prime $$ ϕη′ mass spectrum in 2.0–2.1 GeV region in the $$J/\psi \rightarrow \phi \eta \eta ^\prime $$ J/ψ→ϕηη′ decay. We construct all the $$s s {\bar{s}} {\bar{s}}$$ sss¯s¯ tetraquark currents with $$J^{PC} = 1^{+-}$$ JPC=1+- , and use them to perform QCD sum rule analyses. One current leads to reliable QCD sum rule results and the mass is extracted to be $$2.00^{+0.10}_{-0.09}$$ 2.00-0.09+0.10 GeV, suggesting that the structure X can be interpreted as an $$s s {\bar{s}} {\bar{s}}$$ sss¯s¯ tetraquark state with $$J^{PC} = 1^{+-}$$ JPC=1+- . The Y(2175) can be interpreted as its $$s s {\bar{s}} {\bar{s}}$$ sss¯s¯ partner having $$J^{PC} = 1^{--}$$ JPC=1-- , and we propose to search for the other two partners, the $$s s {\bar{s}} {\bar{s}}$$ sss¯s¯ tetraquark states with $$J^{PC} = 1^{++}$$ JPC=1++ and $$1^{-+}$$ 1-+ , in the $$\eta ^\prime f_0(980)$$ η′f0(980) , $$\eta ^\prime K {\bar{K}}$$ η′KK¯ , and $$\eta ^\prime K {\bar{K}}^*$$ η′KK¯∗ mass spectra.

Abstract. Objective:. To describe the epidemiological characteristics of leprosy in China and to provide evidence for making specific strategies in the leprosy control program. Methods:. We used a descriptive analysis method to analyze the leprosy data from 2017 provided by the Leprosy Management Information System in China (LEPMIS) covering all the provinces of China excluding Hong Kong, Macao, and Taiwan. Results:. In 2017, 634 newly detected cases of leprosy were reported, with a case detection rate of 0.046 per 100,000 individuals. The proportions of cases in children under 15, multibacillary cases, and cases with grade 2 disability were 1.4%, 91.8%, and 20.0%, respectively. A total of 52 relapse cases, among which 28 cases occurred after multidrug therapy, were reported. By the end of 2017, the total number of registered cases was 2,697, with a prevalence rate of 0.194 per 100,000 individuals. Conclusion:. In China, the overall leprosy prevalence is still at a low level, but its distribution is unbalanced, with higher incidence in Yunnan, Sichuan, Guizhou, and Guangdong. To continue making progress toward eliminating leprosy, control efforts must be sustained over the coming years.

Abstract Background Hepatitis B virus (HBV) infection is the major public health problem worldwide. In clinical practice, serological and molecular assays are the most commonly used diagnostic methods to detect HBV infection in clinical practices. Methods Here we present a rapid and sensitive recombinase aided amplification assay (RAA) to detect HBV at 39.0 °C for 30 min without DNA extraction from serum samples. The analytical sensitivity of RAA assay was 100 copies per reaction and showed no cross reaction with human immunodeficiency virus (HIV) and hepatitis C virus (HCV). The universality of RAA assay was validated by testing of 41 archived serum samples with predefined HBV genotypes (B, C and D). Results A total of 130 archived suspected HBV infected serum samples were detected by commercial qPCR with DNA extraction and RAA assay without DNA extraction (heat-treatment). Compared with qPCR assay as a reference, the RAA assay obtained 95.7% sensitivity and 100% specificity and a kappa value of 0.818. Conclusions We developed a rapid, convenient, highly sensitive and specific method to detect HBV without DNA extraction in clinical samples. This RAA method of HBV detection is very suitable for clinical testing.

FeNi-based hybrid materials are among the most representative catalysts for alkaline oxygen evolution reaction (OER), but the modulation of their surface atoms to achieve the optimal catalytic properties is still a big challenge. Here, we report the surface modification of Ni(OH)2/nickel foam (NF)-based electrocatalyst with a trace amount of ferrocene formic acid (FFA) (FFA-Ni(OH)2/NF) for highly efficient OER. Owing to the strong electron interaction and synergistic effects of Fe-Ni heteroatoms, FFA-Ni(OH)2/NF exhibits an overpotential of 311 mV at a current density of 100 mA cm−2. Impressively, the overpotential of FFA-Ni(OH)2/NF at 100 mA cm−2 is 108 mV less than that of bulk phase doped Ni/FFA(OH)2/NF, demonstrating the surprising effect of heteroatomic surface modification. In addition, by introducing a small amount of surface modifier into the electrolyte, the weak surface reconstruction process in the electrochemical process can be fully utilized to achieve obvious modification effects. Therefore, this work fully proves the feasibility of improving catalytic activities of FeNi-based catalysts by modifying surface heterogeneous atom pairs.

Background: To evaluate the preoperative diagnostic efficacy of 3D-MRI for the depth of myometrial invasion of endometrial carcinoma. Methods: A total of 116 patients with endometrial carcinoma who had undergone pelvic MRI before surgery were included. Mimics 21.0 (Materialize Co., Belgium) software was used to reconstruct three-dimensional MRI models (3D-MRI). The tumor volume and surface area, uterine volume and surface area were measured, and the tumor volume ratio was calculated. TVR (Tumor Volume Ratio) = tumor volume/uterine volume, TAR (Tumor Area Ratio) = tumor surface area/uterine surface area. Postoperative pathology was used as the gold standard to compare the accuracy, sensitivity, specificity, negative predictive value, and positive predictive value of conventional MRI and 3D-MRI in preoperative assessment of endometrial carcinoma myometrial invasion. Results: The accuracy and specificity of 3D-MRI in the diagnosis of deep myometrial invasion were better than conventional MRI (p < 0.05). There was no statistically significant difference in tumor volume or surface area between stage IA and stage IB (p > 0.05), while TVR and TAR showed significant statistical differences (8.05 ± 0.66 vs. 19.12 ± 3.20, p < 0.01; 21.38 ± 1.04 vs. 35.15 ± 3.42, p < 0.01). Further analysis, the area under the ROC curve of TVR is 0.738, p < 0.01, and the best cut-off value is 13.59%; the area under the ROC curve of TAR is 0.770, p < 0.01, and the best cut-off value is 27.41%. Conclusions: Preoperative 3D-MRI can effectively assess the myometrial invasion of endometrial carcinoma.

The construction of a hierarchically ordered “brick-and-mortar” structure with a high content of “brick” phase is a key challenge in the preparation of nacre-mimetic composites. Herein, inspired by the transverse cracks in the ceramic lamellae after freeze-drying caused by the secondary nucleation of ice crystals during directional freezing of water-based ceramic slurry, we propose a new idea to use these structural defects and an in-situ reaction to construct composites with a nacre-like “brick-and-mortar” structure and high hard-phase content. This uses ice-templating to first prepare lamellar TiO2 scaffolds with transverse cracks that separated the ceramic lamellae into “brick” whose size was controlled by adjusting the initial ceramic particle size (50, 300, and 700 nm). After the reactive infiltration, these cracks were filled with molten Al, leading to the formation of a “brick-and-mortar” structure with a high hard-phase content (86 vol%). The increasing ceramic particle size reduced the hard-phase content but significantly increased the aspect ratio (height/width) of the ceramic “brick” and the fracture toughness. The excellent damage tolerance was attributed to multiple toughening mechanisms, i.e., multiple cracking, crack deflection, and uncracked-ligament bridging of the metal layers. The existence of “mortar” increased the probability of the formation of multiple cracking.

Hypervirulent Klebsiella pneumoniae strains are typically associated with severe infections and susceptible to most antimicrobial agents. In 2017, a carbapenem-resistant hypervirulent K. pneumoniae (CR-hvKP) strain was isolated from the sputum of a chronic obstructive pulmonary disease (COPD) patient in Zhejiang, China. The goal of the present study was to characterize the molecular features of the CR-hvKP isolate ZJ27003 and its blaKPC-2-harboring plasmid p27003_KPC. Antimicrobial susceptibility was evaluated using the broth microdilution and agar dilution methods. String tests, serum-killing and mouse survival assays were performed to assess virulence, and plasmid conjugation was performed by filter mating. The complete genome sequence of ZJ27003 was acquired using a hybrid assembly of Illumina and Nanopore platform data. The sequence type (ST) of this CR-hvKP isolate was identified as ST23, which exhibits hypervirulence with high serum resistance and murine infection model. The strain is also resistant to carbapenems (imipenem, meropenem and ertapenem), aztreonam and cephalosporins. Additionally, the CR-hvKP isolate carries a 36,708-bp blaKPC-2-harboring plasmid, named p27003_KPC, belonging to the P1 incompatibility (Inc) group. The backbone of p27003_KPC is similar to that of a blaGES-5-harboring Pseudomonas aeruginosa plasmid, in which the blaGES-5 and its surrounding regions were replaced by a blaKPC-2-containing translocatable unit derived from Enterobacteriaceae. The results of a conjugation assay revealed that p27003_KPC can be transferred from K. pneumoniae to P. aeruginosa PAO1 and make the recipient resistant against carbapenem. The identification of a carbapenem-resistant hypervirulent K. pneumoniae isolate carrying and disseminating the blaKPC-2 gene highlights a severe threat to public health.

The Hongguleleng Cu deposit is a Manto-type deposit in the Central Asian Orogenic Belt, located in the east section of West Junggar, Xinjiang, China. It is hosted by Middle Ordovician volcano-sedimentary sequence, especially for porous units. Specifically, the orebodies of this Manto-type deposit are hosted in basalt, andesite, and andesitic breccia host rocks (the particular volcano-sedimentary sequence). The occurrence of these orebodies is controlled by normal faults. Chalcopyrite, pyrite, calcite, chlorite, and epidote are most common minerals of the Hongguleleng deposit. Three alternation belts and six ore related stages have been recognised. The epidote-chalcopyrite stage, quartz-calcite-chalcopyrite stage, and chlorite stage are ore forming stage. The δ34S of chalcopyrite in ore depositing stages varies from 0.94‰ to 2.59‰, indicating that the origin of sulfur is either magma or host volcanic rock. Further, the 206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb values of the chlorite-chalcopyrite and quartz-calcite-chalcopyrite stages exist in the range of 17.443–17.847 and 17.855–17.973; 15.472–15.495 and 15.493–15.620; and 37.616–37.666 and 37.689–38.114, respectively, indicating that the metal originates from the Middle Ocean Ridge Basalt (MORB). The δ13CPDB value of calcite for the epidote-chalcopyrite stage ores, quartz-calcite-chalcopyrite ores with veinlet characteristics, quartz-calcite-chalcopyrite ores with brecciated characteristics, and chlorite-chalcopyrite ores range from −1.40 to −1.50‰, −2.01 to 0.41‰, −1.15 to 0.75‰, and −0.80 to 1.58‰, respectively, while the 18OSMOW ranges from 8.94–10.42‰, 11.83–13.17‰, 13.59–14.04‰, and 12.34–14.18‰, respectively. The CO isotope of calcite of the Hongguleleng deposit indicates that seawater is an essential fluid for ore formation and that modified seawater interacts with the host rock extensively. The hydrothermal magnetite in the quartz-magnetite stage and chlorite in the ore forming stages indicate that temperature decreases from its early to late stages. High Zn and Pb concentrations over four stages of pyrite, with a relatively stable contents, indicate that the content of Zn and Pb in fluid is also high. The concentration of Cu in these four stages of pyrite of the Hongguleleng deposit follow a decreasing trend, indicating that the concentration of Cu in the ore forming fluid decreases from the early to late stage. Based on information mentioned above, we argue that this deposit is a Manto-type deposit with modified seawater driving forces.

Currently, the mechanism of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) transmission mechanism is unclear; however, it must be considered in conjunction with asymptomatic S. aureus strains colonization dynamics. This epidemiological study aimed to determine the role of the household in CA-MRSA transmission in China. Five patients with culture-confirmed CA-MRSA infection and five control patients were recruited from the Sir Run Run Shaw Hospital in Zhejiang, China, between December 2019 and January 2020. The household members of the patients, their pets, and environmental surfaces were sampled and screened for MRSA colonization. Mass spectrometry identification and antimicrobial susceptibility testing were performed on the MRSA isolates. Whole-genome sequencing and core genome multilocus sequence typing (cgMLST) were performed to determine the origin and transmission of the MRSA isolates in the households. Overall, 14 S. aureus-positive specimens (14.1%, 14/99) were obtained from the five households of patients with CA-MRSA infections, of which 12 (85.7%) were MRSA. The overall positivity of MRSA was 12.1% (12/99) among the samples from the CA-MRSA households, while no MRSA isolates were detected in the five control households. Most MRSA isolates belonged to epidemic CA-MRSA clones, such as ST59 (15/35, 42.9%) and ST508 (15/35, 42.9%). The cgMLST results confirmed that MRSA was transmitted among patients, contacts, and pets in the households and was present on environmental surfaces in the CA-MRSA patients' households. In conclusion, the study revealed that the home environment was an important MRSA reservoir. Therefore, focusing on MRSA decolonization in patients alone is not sufficient for infection control of CA-MRSA.

Our previous study revealed that Shuanghuang Shengbai granule could cure the myelosuppression induced by cyclophosphamide (CTX) in lung cancer. However, its hematopoietic effects and molecular mechanisms remain not fully understood. Therefore, this study was intended to investigate the effects and the underlying mechanisms of Astragaloside IV (AS) and saponins of rhizoma polygonati (SRP), the two main bioactive ingredients of Shuanghuang Shengbai granule, on CTX-induced myelosuppression. CTX inhibited the proliferation and promoted apoptosis in bone marrow hematopoietic stem cells (BMHSCs), accompanied by the increased expression of miR-142-3p. AS and/or SRP treatment could alleviate CTX-induced cell injury and suppress the expression of miR-142-3p. Over-expression of miR-142-3p partially reversed the therapeutic effect of AS and/or SRP on CTX-induced cell injury in BMHSCs. Further mechanism exploration discovered that HMGB1 was the target gene of miR-142-3p, and miR-142-3p negatively regulated the expression of HMGB1. To further explore the function of AS and/or SRP in vivo, we constructed a lung cancer xenograft combined with CTX-induced myelosuppression mouse model, and we found that AS and SRP remarkably reversed the CTX-induced reduction of white blood cells, bone marrow nucleated cells, and thymus index in vivo and did not affect the chemotherapy effect of lung cancer. Collectively, our results strongly suggested that AS and SRP could improve the hematopoietic function of myelosuppressed lung cancer mice, and their effects may be related to the inhibition of miR-142-3p expression in BMHSCs.

BackgroundThe rate of carcinoma upgrade for atypical ductal hyperplasia (ADH) diagnosed on core needle biopsy (CNB) is variable on open excision. The purpose of the present study was to develop and validate a simple-to-use nomogram for predicting the upgrade of ADH diagnosed with ultrasound (US)-guided core needle biopsy in patients with US-detected breast lesions.MethodsTwo retrospective sets, the training set (n = 401) and the validation set (n = 186), from Fudan University Shanghai Cancer Center between January 2014 and December 2019 were retrospectively analyzed. Clinicopathological and US features were selected using univariate and multivariable logistic regression, and the significant features were incorporated to build a nomogram model. Model discrimination and calibration were assessed in the training set and validation set.ResultsOf the 587 ADH biopsies, 67.7% (training set: 267/401, 66.6%; validation set: 128/186, 68.8%) were upgraded to cancers. In the multivariable analysis, the risk factors were age [odds ratio (OR) 2.739, 95% confidence interval (CI): 1.525–5.672], mass palpation (OR 3.008, 95% CI: 1.624–5.672), calcifications on US (OR 4.752, 95% CI: 2.569–9.276), ADH extent (OR 3.150, 95% CI: 1.951–5.155), and suspected malignancy (OR 4.162, CI: 2.289–7.980). The model showed good discrimination, with an area under curve (AUC) of 0.783 (95% CI: 0.736–0.831), and good calibration (p = 0.543). The application of the nomogram in the validation set still had good discrimination (AUC = 0.753, 95% CI: 0.666–0.841) and calibration (p = 0.565). Instead of surgical excision of all ADHs, if those categorized with the model to be at low risk for upgrade were surveillanced and the remainder were excised, then 63.7% (37/58) of surgeries of benign lesions could have been avoided and 78.1% (100/128) malignant lesions could be treated in time.ConclusionsThis study developed a simple-to-use nomogram by incorporating clinicopathological and US features with the overarching goal of predicting the probability of upgrade in women with ADH. The nomogram could be expected to decrease unnecessary surgery by nearly two-third and to identify most of the malignant lesions, helping guide clinical decision making with regard to surveillance versus surgical excision of ADH lesions.

Background: Limited studies have examined the impact of airborne particulate matter of 2.5 μm or less (PM2.5) on renal function. No study has examined the effect of PM1, which is small enough to reach the blood circulation. We examined whether exposure to PM1 or PM2.5 affected renal function of young Han Chinese. Method: We included 2,546,047 young adults who were aged 18 to 45 years, being Han ethnicity and had no chronic disease from a Chinese national birth cohort. Serum creatinine (Scr) of each participant was measured during the baseline examination. Estimated glomerular filtration rate (eGFR) were calculated for each participant using the latest Chronic Kidney Disease Epidemiology Collaboration equation. One-year average exposure to PM1 and PM2.5 prior to the health examination for each participant were estimated using machine learning models with satellite remote sensing information. Generalized additive mixed models were used to estimate associations between PM1 or PM2.5 and renal function after adjusting for detailed individual variables. Results: A 10 μg/m3 increment in PM1 exposure was associated with −0.95% (95%CI: −1.04%, −0.87%) difference of eGFR in females and −0.37% (95%CI: −0.44%, −0.31%) in males. For PM2.5, the corresponding difference of eGFR was −0.99% (95%CI: −1.05%, −0.93%) in females and −0.48% (95%CI: −0.53%, −0.43%) in males, respectively. Associations between eGFR and PM were higher in females compared to males (p

The aim of this study was to examine the effect of extract of pre-germinated brown rice (EP) on metabolic and cardiovascular dysfunction in a rat model of T2DM. Hypertensive rats were divided into: (1) normal diet (ND group), (2) induced T2DM (DM group), and T2DM rats that were treated with (3) EP30 mg/kg (EP30 group) or (4) EP300 mg/kg (EP300 group) per day for 4 weeks. T2DM symptoms included: weight loss, hyperglycaemia, hypoinsulinemia, hyperlipidaemia, higher HbA1c, glucose in urine, and lower GLP-1. EP treatment improved metabolic parameters, activated insulin signalling, and increased lipid metabolism, and also ameliorated T2DM-associated increases in levels of inflammation, free radicals, cardiac hypertrophy and fibrosis. EP reduced T2DM and related cardiovascular complications by increasing insulin signalling and lipid metabolism, and reducing levels of inflammation and free radicals. Thus, EP may be a potential candidate for the treatment of metabolic syndrome and related cardiovascular complications.

Aim: Angiogenesis plays an important role in the initiation, development, and metastasis of malignant tumors. Antiangiogenic drugs combined with immune therapy are considered to have a synergistic effect on anti-tumor strategy. Weichang’an formula (WCAF) is a prescription of traditional Chinese medicine (TCM) based on pharmaceutical screening and clinical experience. The aim of this study is to examine the effect of WCAF and its combined action with Bevacizumab (BEV) in colorectal cancer, and to identify the possible mechanism of action.Methods: A human colon cancer cell (HCT 116) subcutaneous xenograft model was established in BALB/c-nu/nu mice. Tumor-bearing mice were randomized into each of four groups: control, WCAF treated, BEV treated, and WCAF plus BEV treated. Apoptosis was detected by TUNEL assay. Western blot was used to assess the protein levels of Leptin-R, STAT3, p-STAT3, BCL-2, and VEGFR-1. Immunohistochemistry was used to detect the micro-vessel density (MVD) and AKT1. Leptin and Vascular endothelial growth factor A (VEGF-A) mRNA expression were detected by Real-time PCR (RT-PCR). A network pharmacology study and validation assay were carried out to find the underlying molecular targets of WCAF related to immune regulation.Results: Compared with the control group, WCAF reduced tumor weight and volume, as well as promoted tumor cell apoptosis. WCAF treatment decreased the mRNA expression of Leptin and VEGF-A, while the protein levels of CD31, LEP-R, VEGFR-1, STAT3, and p-STAT3 were decreased in tumor tissues. In addition, VEGFR-1 protein expression was decreased in the WCAF group and the WCAF plus BEV group but not in the BEV group. The combination of WCAF and BEV demonstrated a partial additive anti-tumor effect in vivo. The pharmacological network also found there are 26 WCAF target proteins related to cancer immune and 12 cancer immune related pathways. The AKT1 protein expression in the WCAF and WCAF + BEV groups were significantly lower than the that in the control group (p < 0.01).Conclusion: WCAF can inhibit tumor growth and promote apoptosis and inhibit tumor angiogenesis in subcutaneous xenografts of human colon cancer HCT-116 in nude mice. WCAF also makes up for the deficiency of BEV by inhibiting VEGFR-1. The VEGFR-1 expression between the combination group and BEV alone achieved statistically significant difference (p < 0.01). Combined with BEV, WCAF showed a partial additive anti-tumor effect. The mechanism may be related to Leptin/STAT3 signal transduction, VEGF-A, VEGFR-1 and WCAF target proteins related to cancer immune such as leptin and AKT1.

Background: Little is known about the effect of ambient temperature on preterm birth, especially for the trimester-specific effects. Objective: To evaluate whether exposure to relatively low or high temperature during pregnancy is associated with increasing risk of preterm birth or not. Method: We analysed the data of a birth cohort with 1,281,859 singleton pregnancies during 2013–2014 and matched the home address of each pregnant women to the model based daily meteorological and air pollution data. Then we used the Cox proportional hazard regression models with random effect to estimate the non-linear associations between exposure to relatively low or high temperature at each trimester of pregnancy and the risk of preterm birth, after controlling for air pollution and individual-level covariates. Finding: The overall preterm birth rate was 8.1% (104,493 preterm births). Exposure to relatively low or high temperatures during the entire pregnancy significantly increase the risk of preterm birth, with hazard ratios (HRs) [95% confidence intervals (CIs)] of 1.03 (95%CI: 1.02, 1.04) for relatively low (9.1 ℃, the 5th percentile) temperature and 1.55 (95%CI: 1.48, 1.61) for relatively high (23.0 ℃, the 95th percentile) temperature in comparison with the thresholds (12.0 ℃). Pregnant women at the early pregnancy (the 1st and 2nd trimester) are more susceptible to high temperatures while pregnant women at the late pregnancy (the 3rd trimester) are more susceptible to low temperatures. Conclusion: These findings provide new evidence that exposure to relatively low or high temperatures during pregnancy increases the risk of preterm birth, which can serve as scientific evidence for prevention of preterm birth.

To assess the genomic profiles of tigecycline (Tgc)-resistant Acinetobacter baumannii, including antibiotic resistance (AR) genes and virulence factors (VF), whole-genome shotgun sequencing was performed on 19 Tgc-resistant (TgcR) A. baumannii strains collected in a tertiary hospital during the early phase of the clinical introduction of Tgc in China from late 2012 to mid-2014. The major sample types containing TgcR strains were sputum and drain fluid. Data from an average of 624 Mbp of sequence was generated on each bacterial genome, with Q30 quality of 90%, and an average coverage of 96.6%. TCDC-AB0715 was used as a reference genome. The genome sequences were annotated for functional elements including AR genes, VFs, genome islands, and inserted sequences before they were comparatively analyzed. The antibiotic susceptibility phenotypes of the strains were examined by a broth microdilution method to determine the minimal inhibitory concentration (MIC) of strains against major clinical antibiotics. The AR genes (ARGs) were annotated using the Comprehensive Antibiotic Resistance Database (CARD). Thirty-three ARGs were shared by all 19 TgcR strains, and 24 ARGs were distributed differently among strains. A total of 391 VFs were found to be diversely distributed in all TgcR strains. Based on ARG number distribution, the 19 TgcR strains were divided into several groups. Highly differentiated genes included gpi, mphG, armA, msrE, adec, catB8, aadA, sul1, blaOXA–435, aph3i, and blaTEM–1, which may represent gene markers for TgcR A. baumannii sub-types. In addition, when compared with Tgc-sensitive (TgcS) strains collected during the same period, TgcR strains featured enrichment of ARGs including aph6id, aph3ib, and teta. Compared with 26 other whole-genome sequences of A. baumannii deposited in GeneBank, TgcR strains in this study commonly lacked the EF-Tu mutation for elfamycin resistance. Previous investigation of three A. baumannii strains isolated from one patient indicated genomic exchange and a homologous recombination event associated with generation of tigecycline resistance. This study further analyzed additional TgcR strains. Phylogenetic analysis revealed a close evolutionary relationship between 19 TgcR strains and to isolates in East and Northeast China. In short, the comprehensive functional and comparative genomic analysis of 19 clinical TgcR A. baumannii strains isolated in the early stage of Tgc usage in China revealed their close phylogenetic relationship yet variable genetic background involving multiple resistance mechanisms. Using a simple ARG or VF gene number diversity method and marker genes, TgcR strain sub-types can be identified. The distinct characteristics of TgcR A. baumannii strains with versatile genomic resistance and regulation patterns raise concern regarding prediction and control of Tgc resistance in the clinic.

ABSTRACT The emergence and spread of carbapenem-resistant hypervirulent Klebsiella pneumoniae sequence type 11 (ST11-CR-HvKP) in China are a great concern in the public health community. However, the underlying mechanism that enables its wide dissemination in China remains unclear. Here, we investigated the prevalence of carriage of carbapenemase-producing Enterobacteriaceae (CPE) among inpatients with diarrhea in a teaching hospital over 1 year to identify ST11-CR-HvKP reservoirs and to understand the genetic background and plasmid profiles of these pathogens. As assessed by stool analysis, the CPE colonization rate (12.4%) among the inpatients with diarrhea was high (12.4%). Antibiotic exposure, surgical history, and CPE positivity were correlated. Genomic investigation of 65 carbapenem-resistant K. pneumoniae isolates indicated a shared bacterial population in various wards. According to maximum likelihood phylogenetic tree analysis, these isolates were partitioned into three major clades. Analysis of the wzi locus revealed three different K types (KL105, KL47, and K64) among the ST11 isolates, indicating the genetic diversity of these isolates. Genetic and sequence mapping revealed the complexity of virulence and resistance plasmid sets harbored by the isolates. These observations indicate that the dissemination of resistant bacteria is more complex than initially anticipated and possibly involves multiple K. pneumoniae ST11 lineages and a variety of virulence plasmids. Collectively, we show for the first time that stool may be a source of ST11-CR-HvKP isolates. Furthermore, the findings reveal the silent dissemination of ST11-CR-HvKP bacteria in Zhejiang Province, China. Future investigations are warranted to determine the association between rectal colonization by ST11-CR-HvKP and clinical infections. IMPORTANCE China has been experiencing a rapid increase in the number of nosocomial infections caused by carbapenem-resistant Klebsiella pneumoniae ST11 (ST11-CRKP) for decades. The emergence of hypervirulent ST11-CRKP (ST11-CR-HvKP) strains is expected to become a serious public health issue in China, considering that carbapenem resistance and virulence have converged in an epidemic clone. K. pneumoniae strains that colonize the human intestinal tract may become a reservoir of virulence and carbapenemase-encoding genes. Here, we first characterized the genotypes and antimicrobial phenotypes of ST11-CR-HvKP strains isolated from diarrheal stool samples of inpatients in Zhejiang Province, China. Active surveillance approaches based on the findings of the present study should be implemented, particularly in intensive care units, to combat the spread of ST11-CR-HvKP and to improve treatment.

Multidrug-resistant Klebsiella pneumoniae and hypervirulent K. pneumoniae (hvKP) have traditionally been considered two individual populations; however, strains displaying both phenotypes have emerged during the recent decade. Understanding the genotypic and phenotypic basis of the convergence could be of clinical importance. In this study, we aimed to evaluate the pathogenicity associated with different combinations of genotypes (i.e., sequence types, virulence factors, and capsular serotypes) and phenotypes (i.e., hypermucoviscosity and drug susceptibility) in K. pneumoniae. A total of 11 K. pneumoniae isolates causing bloodstream infections were included in the study, and they were assigned to seven STs (ST23, ST15, ST268, ST660, ST86, ST65, and ST1660) and carried various K-loci (KL1, KL2, KL16, KL20, and KL24). Hypermucoviscosity was observed for six isolates. blaKPC–2 was detected in six carbapenem-resistant isolates, and the remaining ones were either multidrug-resistant or resistant to two types of antibiotics. Aerobactin- and yersiniabactin-encoding genes were detected in all isolates. Although rmpA2 was detected in all isolates, most contained frameshift mutations (82%). Genes encoding salmochelin, RmpA, and PEG344 were detected in seven isolates. Colibactin-encoding genes were carried by six isolates. Discrepancies among measured virulence in Galleria mellonella and the serum-killing assay, and genotypes and phenotypes were detected. The results illustrate the complexity and difficulty with the current knowledge of hypervirulence to predict the phenotype by using genetic and phenotypic markers. Additionally, the emergence of carbapenem resistance in two isolates of KPC-2-producing hvKP of different sequence types emphasizes the urgency with which reliable clinical diagnostics for hvKP is needed.

Aromatic compounds derived from aromatic amino acids are an important class of diverse chemicals with a wide range of industrial and commercial applications. They are currently produced via petrochemical processes, which are not sustainable and eco-friendly. In the past decades, significant progress has been made in the construction of microbial cell factories capable of effectively converting renewable carbon sources into value-added aromatics. Here, we systematically and comprehensively review the recent advancements in metabolic engineering and synthetic biology in the microbial production of aromatic amino acid derivatives, stilbenes, and benzylisoquinoline alkaloids. The future outlook concerning the engineering of microbial cell factories for the production of aromatic compounds is also discussed.

The prion protein (PRNP) gene encoding prion protein is considered a prerequisite for the occurrence of scrapie disease, and knockout of the PRNP gene in transgenic goat is one effective approach to avoid scrapie. This study aims to establish an event-specific droplet digital polymerase chain reaction (ddPCR) assay to detect and quantify the content of genetically modified (GM) PRNP-knockout goat event KoP1. The developed ddPCR assay presents high specificity, sensitivity, accuracy, precision and wide dynamic range. The limits of detection and quantification were as low as 1.44 and 7.2 haploid genome equivalent (HGE) per reaction, respectively. Furthermore, this assay was successfully applied in quantifying the goat KoP1 GM content in milk, feces and living environmental soil samples. We believe that the developed ddPCR assay has the potential to be used in the evaluation of horizontal gene transfer and the practical risk assessment of GM goat event KoP1 and its derivatives.

As the cultivation scale of genetically modified (GM) crops strongly increases, a convenient DNA assay is highly demanded in resource-limited areas. A label-free electrochemical impedance (EI) genosensor using gold carbon dots (GCDs) was developed with easy-to-use portable device. GCDs were used to modify screen-printed carbon electrode and immobilize capture probes by conducting a simple protocol. After the amplification products anchored on the sensor surface via hybridization reactions, the EI signal increased due to the formation of biocomplex hampering the interfacial electron transfer. Under the optimal conditions, the proposed genosensor coupled with recombinase polymerase amplification (RPA) could detect maize Ruifeng12-5 in a linear range of 0.10–5.0% with a detection limit of 0.10%. In addition, combined with a one-step extraction and RPA amplification, the proposed sensor device can be applied in resource-limited laboratories without expensive instruments or professionals. Therefore, the developed method provides an easy-to-use and sensitive platform for GM organism detection.

Abstract Background This study aimed to investigate the relationship between the rate of carbapenem-resistant Gram-negative bacteria and antibiotic consumption intensity in 153 tertiary hospitals from China in 2014. Methods A retrospective study using national surveillance data from 2014 was conducted. Data on the annual consumption of each antibiotic, as well as the rate of carbapenem-resistant Gram-negative bacteria, were collected from each participating hospital, and the correlation between antibiotic consumption and carbapenem- resistant rate was analyzed. Results The overall antibiotic consumption intensity among the hospitals varied between 23.93 and 86.80 defined daily dosages (DDDs) per 100 patient-days (median, 46.30 DDDs per 100 patient-days). Cephalosporins were the most commonly used antibiotic, followed by quinolones, penicillins, and carbapenems, and the rate of carbapenem-resistant Gram-negative bacteria from each hospital varied. The correlations between carbapenem consumption intensity and rate of carbapenem resistance revealed correlation factors of 0.271 for Escherichia coli (p

An optical waveguide was fabricated by H+ ion implantation with an energy of 400 keV and a dose of 8 × 1016 ions/cm2 in the oxyfluoride glass for the first time to the best of our knowledge. The dark mode spectra of the waveguide were measured by a prism coupling method before and after the thermal treatment. The number of modes was reduced after annealing. The implantation process of 400 keV H+ ions into the oxyfluoride glass was simulated by using the SRIM 2013 program. The refractive index distribution of the ion-implanted waveguide was reconstructed by the reflection calculation method. The refractive index was decreased in the waveguide region and there was an optical barrier with a reduced refractive index at the end of the ion range. The proton-implanted oxyfluoride glass waveguide is a desirable alternative for the fabrication of a compact optical integrated device. Keywords: Waveguide, Ion implantation, Oxyfluoride glasses

Objective To identify the new designer drugs which are totally unknown and not in the routine testing list by the technologies such as high-resolution mass spectrometry in drug facilitated sexual assault, in order to solve the problem in actual cases. Methods The milky fluid from an actual case was extracted and analyzed using LC-QE, 1H-NMR and GC-MS, respectively. The accurate masses and cluster ions isotope patterns of unknown compound were obtained by LC-QE. The molecular formula was confirmed as C16H12Cl2N2O based on the protons number of 1H-NMR. The isomers diclazepam and 4-chlorodiazepam were separated and detected with GC-MS. Results The new designer benzodiazepine as diclazepam in the milky fluid was identified. The results provided direct evidence for the investigation and qualitative analysis of such cases. Conclusion The combined application of various methods, including LC-QE, 1H-NMR and GC-MS, can be used to detect unknown new psychoactive substances.

This study examined the effects of eugenosedin-A (Eu-A) in a streptozotocin (STZ)/nicotinamide-induced rat model of type II diabetes mellitus (T2DM). Six-week-old Sprague–Dawley rats were randomly divided into three groups: (1) RD group, normal rats fed a regular diet (RD), (2) DM group, T2DM rats fed a high-fat diet, and (3) Eu-A group, T2DM rats fed a high fat diet plus oral Eu-A (5 mg/kg/day). After 30 days, the DM group had higher body weight, higher blood glucose and lower insulin levels than the RD group. The DM group also had increased protein expression of glycogen synthase kinase (GSK) in liver and skeletal muscle and decreased protein expression of insulin receptor (IR), insulin receptor substrate-1 (IRS-1), IRS-2, AMP-activated protein kinase (AMPK), glucose transporter-4 (GLUT-4), glucokinase (GCK), and peroxisome proliferator-activated receptor γ (PPAR-γ). STZ/nicotinamide-induced T2DM increased the expression of mitogen-activated protein kinases (MAPKs: p38, ERK, JNK) and inflammatory p65 protein. In the Eu-A treated T2DM rats, however, blood glucose was attenuated and the insulin concentration stimulated. Changes in IR, IRS-1 and IRS-2 proteins as well as AMPK, GLUT-4, GCK, GSK, PPAR-γ, MAPKs, and inflammatory p65 proteins were ameliorated. These results suggested that Eu-A alleviates STZ/nicotinamide-induced hyperglycemia by improving insulin levels and glucose metabolism, and inhibiting the MAPKs- and p65-mediated inflammatory pathway.

Abstract This paper presents a practicable regional division and cut algorithm for minimizing the sum of linear fractional functions over a polyhedron. In the algorithm, by using an equivalent problem (P) of the original problem, the proposed division operation generalizes the usual standard bisection, and the deleting and reduction operations can cut away a large part of the current investigated region in which the global optimal solution of (P) does not exist. The main computation involves solving a sequence of univariate equations with strict monotonicity. The proposed algorithm is convergent to the global minimum through the successive refinement of the solutions of a series of univariate equations. Numerical results are given to show the feasibility and effectiveness of the proposed algorithm.

Objective: Big submucosal myoma often causes heavy menstrual bleeding and are complicated in hysterscopic surgery. High Intensity Focused Ultrasound (HIFU), is a method for myoma ablation therapy, which may benefit on size reduction, and assist following hysterscopic myomectomy. Case report: Two cases, case one,. 44-year-old female with 3.8 cm submucosal myoma, STEPW (Size, Topography, Extension, Penetration and Wall) score 6 and case 2. 48-year-old female, with 6.0 cm submucosal myoma, STEPW score 8, both received HIFU treatment before hysterscopic myomectomy was done. The myomas reduced after 5 months with improvement of anemia. The following hysterscopic myomectomy shows less operative time and fewer blood loss. Conclusion: HIFU reduce size of submucosal myoma and may improve anemia after months. Less operating time and blood loss were demonstrated in the following hysterscopic myomectomy. For well selected patients, combined treatment with HIFU and hysteroscopic resection may decrease complication rate. Keywords: High Intensity Focused Ultrasound (HIFU), Hysteroscopic myomectomy, Submucosal myoma