[Impact of the depth of remission by induction chemotherapy on the prognosis of limited stage small cell lung cancer].

Objective: To evaluate the effect of depth of remission of induction chemotherapy on the overall prognosis of limited stage small cell lung cancer (L-SCLC). Methods: The study was a retrospective, L-SCLC patients who contained complete imaging data and underwent consecutive standardized treatments at the Department of Thoracic Radiation and Medical Oncology, Zhongnan Hospital of Wuhan University between January 2013 and June 2021 were included. To delineate the volume of tumor before and after induction chemotherapy and to calculate the depth of remission caused by the induced chemotherapy. The time receiver operating characteristic (timeROC) method was used to determine the optimal predictors for prognosis, multi-factor analysis using Cox risk proportional model. Results: A total of 104 patients were included in this study. The median PFS and OS of this cohort were 13.7 months and 20.9 months, respectively. It was observed by timeROC analysis that residual tumor volume after induction chemotherapy had the optimal predictive value of PFS at 1 year (AUC=0.86, 95% CI: 0.78~0.94) and OS at 2 years (AUC=0.76, 95% CI: 0.65~0.87). Multivariate analysis showed residual tumor volume after induction chemotherapy was the independent prognostic factor to PFS (HR=1.006, 95% CI: 1.003~1.009, P<0.01) and OS (HR=1.009, 95% CI: 1.005~1.012, P<0.001). For those whose residual tumor volume remitted to less than 10 cm(3) after induction chemotherapy, the favorable long-term outcomes could be achieved, regardless of their initial tumor load. Conclusion: The depth of remission of induction chemotherapy could be a promising prognostic predictor to the L-SCLC and provide the individualized treatment guidance.

[Effect of autoflation on the prognosis of otitis media with effusion in children].

Objective: To investigate the effect of autoinflation on the prognosis of OME in children. Methods: Total of 325 pediatric patients, age ranged from 3 to 8 years, with OME(486 ears)diagnosed in our department from January 2019 to January 2020 were collected. Among them, 177 were males, 148 were females. Disease course ranged from 25 to 86 days. According to watchful waiting and autoinflation application during follow-up, these children were divided into two groups including 183 cases(271 ears) and 142 cases(215 ears), respectively. The average auditory threshold and tympanogram curve type in two groups were analyzed in the period of 3 months follow-up, and the recovery of OME was evaluated. Results: At the end of 1- and 2- month follow-up, the auditory threshold of patients in autoinflation group was significantly lower than that in watchful waiting group (t=2.139 5 and 2.680 6, P<0.05). However, at the end of 3- month follow-up, there was no significant difference between two groups (t=1.158 5, P>0.05). At the end of 1-, 2- and 3- month follow-up, 89 (33%, 89/271), 200 (74%, 200/271), 220 (81%, 220/271) and 176 (82%, 176/215), 178 (83%, 178/215), 183 (85%, 183/215) ears in watchful waiting group and autoinflation group had a hearing threshold <20 dB HL, respectively, in which ears with auditory threshold<20 dB HL in watchful waiting group were significantly less than those in autoinflation group at the end of 1 and 2 month follow-up (P<0.05), However, ears with auditory threshold<20 dB HL in watchful waiting group were not significantly different from that in the autoflation group at the end of 3- month follow-up (P>0.05). The proportion of ears with type A tympanogram curve was 74%(159/215), 79%(170/215), and 85%(183/215) at the end of 1-, 2- and 3- month follow-up in autoinflation group and 36%(98/271), 71%(192/271) and 76%(206/271) in watchful waiting group, respectively. Proportion of ears with type A tympanogram curve in autoflation group was significantly higher than that in watchful waiting group (P<0.05). Conclusion: Autoinflation can improve the hearing of children with OME in early stage, restore normal middle ear pressure, increase recovery rate, and reduce the choice of surgical treatment of OME.

LncRNA RPPH1 predicts poor prognosis and regulates cell proliferation and migration by repressing P21 expression in gastric cancer.

OBJECTIVE: The purpose of this study was to explore the expression and biological functions of long non-coding ribonucleic acid (lncRNA) ribonuclease P RNA component H1 (RPPH1) in gastric cancer (GC), and to analyze the correlations of lncRNA expression with the clinical features and prognosis of GC patients. PATIENTS AND METHODS: The relative expression of RPPH1 in tissue specimens from 60 GC patients was measured via quantitative Reverse Transcription-Polymerase Chain Reaction (qRT-PCR), and the correlations of RPPH1 expression with tumor-node-metastasis (TNM) stage, lymph node metastasis, etc. in GC patients were analyzed. Then, qRT-PCR was performed to detect the relative expression level of RPPH1 in GC cells. Moreover, colony formation assay, 5-Ethynyl-2'-deoxyuridine (EdU) staining, wound-healing assay, and transwell assay were employed to investigate the influence of RPPH1 on GC cell functions. After interfering in the expression of RPPH1, the changes in p21 (CDKN1A, cyclin dependent kinase inhibitor 1A) expression were determined through qRT-PCR and Western blotting. RESULTS: It was shown in qRT-PCR assay results that the expression of RPPH1 was upregulated in 60 cases of GC tissues. Statistical analysis revealed that RPPH1 expression was positively correlated with the TNM stage, lymph node metastasis, and infiltration depth in GC patients. Besides, highly expressed lncRNA RPPH1 suggested poor prognosis of GC patients. Based on the results of qRT-PCR assay, the expression of RPPH1 in GC cells was upregulated. After interfering in RPPH1 expression, both colony formation assay and EdU staining indicated that the proliferative capacity of GC cells was repressed. Furthermore, it was manifested in the results of wound-healing and transwell assays that the migratory and invasive abilities of GC cells were weakened. Finally, the qRT-PCR and Western blotting assay results demonstrated that p21 expression was upregulated after interfering in the expression of RPPH1 in GC cells. CONCLUSIONS: The expression of lncRNA RPPH1 is upregulated in GC, suggesting that the prognosis of the patients is poor. Highly expressed RPPH1 promotes the proliferation and metastasis of GC cells by regulating p21 expression.

Environmental impacts of nitrogen emissions in China and the role of policies in emission reduction.

Atmospheric reactive nitrogen (Nr) has been a cause of serious environmental pollution in China. Historically, China used too little Nr in its agriculture to feed its population. However, with the rapid increase in N fertilizer use for food production and fossil fuel consumption for energy supply over the last four decades, increasing gaseous Nr species (e.g. NH3 and NOx) have been emitted to the atmosphere and then deposited as wet and dry deposition, with adverse impacts on air, water and soil quality as well as plant biodiversity and human health. This paper reviews the issues associated with this in a holistic way. The emissions, deposition, impacts, actions and regulations for the mitigation of atmospheric Nr are discussed systematically. Both NH3 and NOx make major contributions to environmental pollution but especially to the formation of secondary fine particulate matter (PM2.5), which impacts human health and light scattering (haze). In addition, atmospheric deposition of NH3 and NOx causes adverse impacts on terrestrial and aquatic ecosystems due to acidification and eutrophication. Regulations and practices introduced by China that meet the urgent need to reduce Nr emissions are explained and resulting effects on emissions are discussed. Recommendations for improving future N management for achieving 'win-win' outcomes for Chinese agricultural production and food supply, and human and environmental health, are described. This article is part of a discussion meeting issue 'Air quality, past present and future'.

[Acoustic absorbance characteristics of wideband tympanometry in patients with Meniere's disease].

Objective:To study acoustic absorbance characteristics of wideband tympanometry in patients with unilateral Meniere's disease. Method:Acoustic absorbance were detected using wideband tympanometry in 36 patients with unilateral Meniere's disease and 39 control subjects excluding inner ear and middle ear disease. All patients with Meniere's disease underwent electrocochleography, gadolinium contrast internal auditory canal MRI, pure tone test. The integral area formed by the absorbance curve on peak pressure and x-axis(frequency) was calculated. Student's t-test was used to compare integral areas difference of 2 ears in Meniere's disease patients and control group. Result:The integral area of absorbance was greater in affected side than unaffected side and there was no difference in peak values of absorbance between 2 ears in Meniere's disease patients. There was no significant difference in areas between Meniere's disease in different grade(P>0.05). Peak value of absorbance and difference value of absorbance were not significant between Meniere's disease patients and normal control. Only 61.11% Meniere's disease patients showed -SP/AP＞0.4 and 95.24% showed endolymphatic hydrops in affected side. Conclusion:Affected side in patients with Meniere's disease showed higher integral area of absorbance than other side,which is high sensitive but not specific.

[An analysis of the results of video head impulse test in benign paroxysmal vertigo of childhood].

Objective:This study was to analyze the results of video head impulse test (vHIT) of benign paroxysmal vertigo of childhood (BPVC) in order to determine the potential value of vHIT in the diagnosis and treatment for BPVC and to discuss its possible pathogenesis of BPVC. Method:Thirty-six children with BPVC were enrolled. No hearing loss and skull abnormality were found in these children as assessed by pure tone audiometry, acoustic impedance, CT or MRI scan. The vHIT was carried out, and main outcome measures were the gain of vestibulo-ocular reflex, gain asymmetry, and refixation saccades. Eleven healthy children were selected as normal control who came to our hospital for doing a routine checkup and have no history of dizziness. The differences of vHIT results between these two groups were analyzed. Result:①The vHIT results in control group were normal. In all BPVC subjects, abnormalities were detected in 9 patients (25.0%),including vHIT gains decline in 3 patients, abnormal symmetry in 4 patients, and abnormal isolated overt saccades in 2 patients.②The average saccadic gain in different canals of BPVC group was 1.03±0.14, 1.01±0.15, 1.13±0.31, 1.18±0.36, 1.21±0.33, 1.14±0.30 in left horizontal, right horizontal, left anterior, right posterior, right anterior, left posterior canal, respectively; while in normal group, it was 1.14±0.15, 1.18±0.09, 1.16±0.30, 1.18±0.40, 1.34±0.26, 1.30±0.20, respectively. Significant statistical difference was found only in horizontal canals between these two groups (P<0.05). ③Asymmetry of the three pairs of conjugated semicircular canals was 0.04±0.07 (horizontal canal), 0.06±0.04 (left anterior and right posterior canal), 0.06±0.04 (right anterior and left posterior canal) in BPVC group, respectively; while in control group, it was 0.02±0.02, 0.04±0.03, 0.04±0.04,respectively. There was no statistical difference between the two groups (P>0.05). Conclusion:A certain proportion of abnormal peripheral vestibule function in children with BPVC was found. vHIT is a "child friendly," relatively easytouse, and simple tool to evaluate each of the 6 semicircular canals, which may offer some potential clinical information for assessing the vestibule dysfunction for BPVC.

Synthesis of N-doped graphene quantum dots by pulsed laser ablation with diethylenetriamine (DETA) and their photoluminescence.

We report a facile, fast, and one-step approach to prepare N-doped graphene quantum dots (GQDs) using pulsed laser ablation with diethylenetriamine (DETA). The synthesized N-doped GQDs with an average size of about 3.4 nm and an N/C atomic ratio of 26% have been demonstrated. Compared to pristine GQDs, the N-doped GQDs emit enhanced photoluminescence (PL) with a factor as high as 66, originated from the enhanced densities of pyridinic and graphitic N. The temperature-dependent PL of the N-doped GQDs was studied from cryogenic to room temperature. An anomalous temperature dependence of PL intensity was observed for the N-doped GQDs, which was ascribed to a carrier transfer mechanism from a dopant-induced state to the quantum-dot emitting state.

Eco-friendly luminescent solar concentrators with low reabsorption losses and resistance to concentration quenching based on aqueous-solution-processed thiolate-gold nanoclusters.

Heavy-metal-containing quantum dots (QDs) with engineered electronic states have been served as luminophores in luminescent solar concentrators (LSCs) with impressive optical efficiency. Unfortunately, those QDs involve toxic elements and need to be synthesized in a hazardous solvent. Recently, biocompatible, eco-friendly gold nanoclusters (AuNCs), which can be directly synthesized in an aqueous solution, have gained much attention for promising applications in 'green photonics'. Here, we explored the solid-state photophysical properties of aqueous-solution-processed, glutathione-stabilized gold nanoclusters (GSH-AuNCs) with a ligand-to-metal charge-transfer (LMCT) state for developing 'green' LSCs. We found that such GSH-AuNCs exhibit a large Stokes shift with almost no spectral overlap between the optical absorption and PL emission due to the LMCT states, thus, suppressing reabsorption losses. Compared with GSH-AuNCs in solution, the photoluminescence quantum yields (PL-QYs) of the LSCs can be enhanced, accompanied with a lengthened PL lifetime owing to the suppression of non-radiative recombination rates. In addition, the LSCs do not suffer from severe concentration-induced PL quenching, which is a common weakness for conventional luminophores. As a result, a common trade-off between light-harvesting efficiency and solid-state PL-QYs can be bypassed due to nearly-zero spectral overlap integral between the optical absorption and PL emission. We expect that GSH-AuNCs hold great promise for serving as luminophores for 'green' LSCs by further enhancing solid-state PL-QYs.

Genetic analyses of Chinese isolates of Toxoplasma gondii reveal a new genotype with high virulence to murine hosts.

A great deal of evidence demonstrates that a strongly clonal population structure of Toxoplasma gondii strains exists in humans and animals in North America and Europe, while the strains from South America are genetically separate and more diverse. Potential differences in virulence between different strains mean that an understanding of strain diversity is important to human and animal health. However, to date, only one predominant genotype, ToxoDB#9 (Chinese I), and a few other genotypes, including ToxoDB#205, have been identified in China. By using DNA sequence-based phylogenetic analyses, we have re-evaluated the population structure of T. gondii strains collected from China and compared them with other global strains. Based on phylogenetic analysis of restriction fragment length polymorphisms, multilocus sequence typing and intron sequences from T. gondii, we propose that the Chinese isolates described as Chinese I are divided into two groups called Chinese I and Chinese III. Our results demonstrate that significant differences were found in mouse mortality caused by some Chinese strains, and also the archetypal I, II, III strains in mice. Furthermore, a comparison of cyst loading in the brains of infected rats showed some Chinese strains to be capable of a high degree of cyst formation. Furthermore we show that genotyping using neutral genetic markers may not be a useful predictor of pathogenic phenotypes.

Origin of tunable photoluminescence from graphene quantum dots synthesized via pulsed laser ablation.

A one-step synthesis of graphene quantum dots (GQDs) has been implemented using pulsed laser ablation (PLA) with carboxyl-functionalized multiwalled carbon nanotubes (MWCNTs). The synthesized GQDs with an average size smaller than 3 nm were obtained by the fragmentation of MWCNTs via oxidative cutting. The GQDs can generate tunable photoluminescence (PL) ranging from green to blue by controlling the PLA time. The PL spectrum (decay time) of the green GQDs remains unchanged under different excitation energies (emission energies), while that of the blue GQDs correlates with the excitation energy (emission energy). On the basis of the pH and temperature dependence of PL, we suggest that the localized intrinsic states associated with the sp(2) nanodomains and delocalized extrinsic states embedded on the GQD surface are responsible for blue and green emission in GQDs, respectively.

Solid-state, ambient-operation thermally activated delayed fluorescence from flexible, non-toxic gold-nanocluster thin films: towards the development of biocompatible light-emitting devices.

Luminescent gold nanoclusters (AuNCs) with good biocompatibility have gained much attention in bio-photonics. In addition, they also exhibit a unique photo-physical property, namely thermally activated delayed fluorescence (TADF), by which both singlet and triplet excitons can be harvested. The combination of their non-toxic material property and unique TADF behavior makes AuNCs biocompatible nano-emitters for bio-related light-emitting devices. Unfortunately, the TADF emission is quenched when colloidal AuNCs are transferred to solid states under ambient environment. Here, a facile, low-cost and effective method was used to generate efficient and stable TADF emissions from solid AuNCs under ambient environment using polyvinyl alcohol as a solid matrix. To unravel the underlying mechanism, temperature-dependent static and transient photoluminescence measurements were performed and we found that two factors are crucial for solid TADF emission: small energy splitting between singlet and triplet states and the stabilization of the triplet states. Solid TADF films were also deposited on the flexible plastic substrate with patterned structures, thus mitigating the waveguide-mode losses. In addition, we also demonstrated that warm white light can be generated based on a co-doped single emissive layer, consisting of non-toxic, solution-processed TADF AuNCs and fluorescent carbon dots under UV excitation.

[The effect and injury to the airways of different sputum aspiration pressure in a rat model of mucus hypersecretion].

OBJECTIVE: To explore the optimal pressure of sputum aspiration to ensure the effectiveness and safety of clinical operation. METHODS: We established a rabbit model of airway mucus hypersecretion by aerosol acrolein inhalation, and the animals were divided into 4 groups randomly with different sputum aspiration pressure as follows: group A -75 mmHg (1 mmHg=0.133 kPa), group B -150 mmHg, group C -225 mmHg, group D -300 mmHg. Sputum aspiration efficiency and tracheal mucosal damage degree were evaluated by sputum volume, oxygen saturation changes, the pathological sections of tracheal mucosa and the expressions of IL-1ß and TNF-α in airway secretion. RESULTS: The sputum suction volume of group A, B, C, D were (2.72±0.24), (4.81±0.32), (5.03±0.37) and (6.29±0.51) ml, respectively, which was significantly higher in group D, but lower in group A, as compared to other groups (P<0.05). There were no significant differences between B and C groups. The maximal SpO2 decrease of C and D groups [(18.1±5.2)% and(32.4±8.4)%]were significantly higher than those in A and B groups [(4.4±1.7)% and (6.3±2.9)%], and group D was significantly more than group C, and the difference was statistically significant (P<0.05). There were no significant differences between A and B groups. HE staining of tracheal mucosa in C and D groups showed that the inflammatory cell infiltration and mucosal damage were more serious than A and B groups, but the airway mucosal damage of group A was the least. CONCLUSION: The pressure of -150 mmHg was more effective with high oxygen saturation and less airway injury, which may be suitable for clinical sputum aspiration.

Resistance trends among clinical isolates in China reported from CHINET surveillance of bacterial resistance, 2005-2014.

With the aim of gathering temporal trends on bacterial epidemiology and resistance from multiple laboratories in China, the CHINET surveillance system was organized in 2005. Antimicrobial susceptibility testing was carried out according to a unified protocol using the Kirby-Bauer method or automated systems. Results were analyzed according to Clinical and Laboratory Standards Institute (CLSI) 2014 definitions. Between 2005 and 2014, the number of bacterial isolates ranged between 22,774 and 84,572 annually. Rates of extended-spectrum ß-lactamase production among Escherichia coli isolates were stable, between 51.7 and 55.8%. Resistance of E. coli and Klebsiella pneumoniae to amikacin, ciprofloxacin, piperacillin/tazobactam and cefoperazone/sulbactam decreased with time. Carbapenem resistance among K. pneumoniae isolates increased from 2.4 to 13.4%. Resistance of Pseudomonas aeruginosa strains against all of antimicrobial agents tested including imipenem and meropenem decreased with time. On the contrary, resistance of Acinetobacter baumannii strains to carbapenems increased from 31 to 66.7%. A marked decrease of methicillin resistance from 69% in 2005 to 44.6% in 2014 was observed for Staphylococcus aureus. Carbapenem resistance rates in K. pneumoniae and A. baumannii in China are high. Our results indicate the importance of bacterial surveillance studies.

Photo-induced Doping in GaN Epilayers with Graphene Quantum Dots.

We demonstrate a new doping scheme where photo-induced carriers from graphene quantum dots (GQDs) can be injected into GaN and greatly enhance photoluminescence (PL) in GaN epilayers. An 8.3-fold enhancement of PL in GaN is observed after the doping. On the basis of time-resolved PL studies, the PL enhancement is attributed to the carrier transfer from GQDs to GaN. Such a carrier transfer process is caused by the work function difference between GQDs and GaN, which is verified by Kelvin probe measurements. We have also observed that photocurrent in GaN can be enhanced by 23-fold due to photo-induced doping with GQDs. The improved optical and transport properties from photo-induced doping are promising for applications in GaN-based optoelectronic devices.

Newer antifungal agents micafungin and voriconazole for fungal infection prevention during hematopoietic cell transplantation: a meta-analysis.

OBJECTIVE: The new antifungal agents provide further opportunities for effective prophylaxis for fungal infections during stem cell transplantation for patients with hematologic malignancies; however, the efficacy of these antifungal prophylactic drugs has not yet been established. This study was to compare the newer antifungal agents micafungin and voriconazole for prophylaxis effects on the clinical outcomes. MATERIALS AND METHODS: We electronically searched the database of Cochrane Central Register of Controlled Trials, Pubmed, EMbase, and relevant database articles (1996.01-2013.12). Comparative studies were carried out on proved fungal infections, mortality, and adverse effects. Meta-analysis was performed by Review Manager 5.1.6 software and the funnel plot regression was adopted to assess the publication bias. RESULTS: We found 1508 records and 13 studies totaling 3767 patients included in analyses. Pooled comparisons of studies found that antifungal prophylaxis with the new agents does reduce the incidence of invasive fungal infections than fluconazole or itraconazole. The reduction in invasive fungal infections was achieved by using micafungin, voriconazole for antifungal prophylaxis. Using voriconazole prophylaxis can decrease the transplant mortality compared with fluconazole or itraconazole prophylaxis. Voriconazole had higher rates of liver dysfunction, lower gastrointestinal side effects over fluconazole, and lower rates of nephrotoxic effects than amphotericin B. Both micafungin and voriconazole had a significant decrease in adverse events requiring drug discontinuation compared with itraconazole. CONCLUSIONS: This analysis indicated the 2 agents appear to be well tolerated with manageable side effects and beneficial in the prophylaxis of IFI. Further work is needed with a large scale of random controlled trials on the effect of these drugs.

A Facile and Low-Cost Method to Enhance the Internal Quantum Yield and External Light-Extraction Efficiency for Flexible Light-Emitting Carbon-Dot Films.

Solution-processed, non-toxic carbon dots (CDs) have attracted much attention due to their unique photoluminescence (PL) properties. They are promising emissive layers for flexible light-emitting devices. To this end, the CDs in pristine aqueous solutions need to be transferred to form solid-state thin films without sacrificing their original PL characteristics. Unfortunately, solid-state PL quenching induced by extra non-radiative (NR) energy transfer among CDs would significantly hinder their practical applications in optoelectronics. Here, a facile, low-cost and effective method has been utilized to fabricate high-performance CD/polymer light-emitting flexible films with submicron-structured patterns. The patterned polymers can serve as a solid matrix to disperse and passivate CDs, thus achieving high internal quantum yields of 61%. In addition, they can act as an out-coupler to mitigate the waveguide-mode losses, approximately doubling the external light-extraction efficiency. Such CD/polymer composites also exhibit good photo-stability, and thus can be used as eco-friendly, low-cost phosphors for solid-state lighting.

LC-MS/MS: a rapid and simple new method for the determination of carbapenem ß-lactamases.

We investigated the application of liquid chromatography-tandem mass spectrometry (LC-MS/MS) for pan-drug-resistant Acinetobacter baumannii (PDR-AB) with carbapenem resistance. Eight strains were randomly selected from 84 clinical isolates of PDR-AB strains obtained by the Kirby-Bauer and agar dilution methods. An efflux pump inhibition test was used to screen for the efflux pump phenotype. An ethylenediaminetetraacetic acid (EDTA) synergy test was used to screen for the ß-lactamase phenotype, and a three-dimensional test was used to detect extended spectrum ß-lactamase (ESBL) and ampicillin C, KPC, and carbapenemase. ESBL genes were amplified by polymerase chain reaction and sequenced. Outer membrane proteins were extracted from a sensitive strain and the PDR-AB strains by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and subjected to LC-MS/MS. Peptide mass fingerprinting data were retrieved, and proteins with differential expression were identified. Results of the efflux pump inhibition tests showed that the minimum inhibitory concentrations for meropenem were decreased in 4 of the 8 strains by at least 25% of the original value. The results of the EDTA synergy test were negative, and the modified Hodge's tests were positive for all strains. PCR and sequencing confirmed that seven, five, and all eight of the PDR-AB strains contained blaOXA-23, blaTEM-1, and KPC-2, respectively. OXA-23 and CsuC proteins were differentially expressed between the drug-resistant and -sensitive strains. Production of blaOXA-23 enzyme and pilus molecular chaperone to guide synthesis of CsuC protein may be involved in the resistance of A. baumannii to carbapenems. LC-MS/ MS provides a quick and easy method for carbapenemase detection.

Geometrical and morphological optimizations of plasmonic nanoarrays for high-performance SERS detection.

Here we present an in-depth and comprehensive study of the effect of the geometry and morphology of nanoarray (NA) substrates on their surface-enhanced Raman scattering (SERS) performance. The high-quality SERS-active NA substrates of various unit shapes and pitches are assembled through electron beam lithography and fabricated by electron beam physical vapor deposition. Good agreement is found on comparing the Raman scattering results with the integrals of the fourth power of local electric fields from the three-dimensional numerical simulations. A novel type of hybrid NA substrate composed of disordered nanoparticles and a periodic NA is fabricated and characterized. The morphology of NAs has little influence on the SERS performance of hybrid NA substrates and they perform better than both their counterparts pure NA and disordered nanoparticle substrates.

Detection of drug-resistance mechanism of Pseudomonas aeruginosa developing from a sensitive strain to a persister during carbapenem treatment.

We explored the mechanism of the development from sensitivity to resistance to carbapenem in Pseudomonas aeruginosa. Two P. aeruginosa strains were collected during treatment with carbapenem. Strain homology was investigated using pulsed-field gel electrophoresis. Porin oprD2 expression was analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The minimum inhibitory concentrations (MICs) of imipenem and meropenem with or without MC207110 were determined using the agar dilution method. The expression level of efflux pump mRNA was tested using real-time polymerase chain reaction. Metallo-lactamases (MBLs) were screened using the EDTA-disk synergy test. Genes encoding MBLs were amplified and then analyzed by DNA sequencing. The two treated strains belonged to the same pulsed-field gel electrophoresis type. The SDS-PAGE profile of the P. aeruginosa strains revealed that the 46-kDa membrane protein OprD2 of IMP(R)MEM(R) type strains was lost, whereas OprD2 of 1 IMP(S)MEM(S) strain was normal. With or without MC207110 treatment, the MIC of carbapenem-resistant P. aeruginosa decreased by 4-fold, while the MIC of carbapenem-sensitive P. aeruginosa did not. Compared with the carbapenem-sensitive strain, MexX mRNA expression in the carbapenem-resistant strain increased by 102.5-fold, while the mRNA expression of other efflux pumps did not markedly increase. Neither carbapenem-resistant nor carbapenem-sensitive P. aeruginosa produced MBL. The mechanism of development from sensitivity to resistance of P. aeruginosa to carbapenem during carbapenem treatment is due to porin oprD2 loss and an increased expression level of MexXY-OprM.

Superfamily of genes encoding G protein-coupled receptors in the diamondback moth Plutella xylostella (Lepidoptera: Plutellidae).

G protein-coupled receptors (GPCRs) are the largest and most versatile superfamily of cell membrane proteins, which mediate various physiological processes including reproduction, development and behaviour. The diamondback moth, Plutella xylostella (Lepidoptera: Plutellidae), is one of the most notorious insect pests, preferentially feeding on cruciferous plants. P. xylostella is not only one of the world's most widespread lepidopteran insects, but has also developed resistance to nearly all classes of insecticides. Although the mechanisms of insecticide resistance have been studied extensively in many insect species, few investigations have been carried out on GPCRs in P. xylostella. In the present study, we identified 95 putative GPCRs in the P. xylostella genome. The identified GPCRs were compared with their homologues in Bombyx mori and Drosophila melanogaster. Our results suggest that GPCRs in different insect species may have evolved by a birth-and-death process. One of the differences among compared insects is the duplication of short neuropeptide F receptor and adipokinetic hormone receptors in P. xylostella and B. mori. Another divergence is the decrease in quantity and diversity of the stress-tolerance gene, Mth, in P. xylostella. The evolution by the birth-and-death process is probably involved in adaptation to the feeding behaviour, reproduction and stress responses of P. xylostella. Some of the genes identified in the present study could be potential targets for the development of novel pesticides.