[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.

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'.

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.

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.

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.

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.

[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.

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.

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.

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.

Optical coupling from InGaAs subcell to InGaP subcell in InGaP/InGaAs/Ge multi-junction solar cells.

Spatially-resolved electroluminescence (EL) images in the triple-junction InGaP/InGaAs/Ge solar cell have been investigated to demonstrate the subcell coupling effect. Upon irradiating the infrared light with an energy below bandgap of the active layer in the top subcell, but above that in the middle subcell, the EL of the top subcell quenches. By analysis of EL intensity as a function of irradiation level, it is found that the coupled p-n junction structure and the photovoltaic effect are responsible for the observed EL quenching. With optical coupling and photoswitching effects in the multi-junction diode, a concept of infrared image sensors is proposed.

Distance dependence of energy transfer from InGaN quantum wells to graphene oxide.

We report the distance-dependent energy transfer from an InGaN quantum well to graphene oxide (GO) by time-resolved photoluminescence (PL). A pronounced shortening of the PL decay time in the InGaN quantum well was observed when interacting with GO. The nature of the energy-transfer process has been analyzed, and we find the energy-transfer efficiency depends on the 1/d² separation distance, which is dominated by the layer-to-layer dipole coupling.

Efficient energy transfer from InGaN quantum wells to Ag nanoparticles.

Nonradiative energy transfer from an InGaN quantum well to Ag nanoparticles is unambiguously demonstrated by the time-resolved photoluminescence. The distance dependence of the energy transfer rate is found to be proportional to 1/d(3), in good agreement with the prediction of the dipole interaction calculated from the Joule losses in acceptors. The maximum energy-transfer efficiency of this energy transfer system can be as high as 83%.

Probing the photoluminescence properties of gold nanoclusters by fluorescence lifetime correlation spectroscopy.

Gold nanoclusters (Au NCs) have attracted much attention for promising applications in biological imaging owing to their tiny sizes and biocompatibility. So far, most efforts have been focused on the strategies for fabricating high-quality Au NCs and then characterized by conventional ensemble measurement. Here, a fusion single-molecule technique combining fluorescence correlation spectroscopy and time-correlated single-photon counting can be successfully applied to probe the photoluminescence (PL) properties for sparse Au NCs. In this case, the triplet-state dynamics and diffusion process can be observed simultaneously and the relevant time constants can be derived. This work provides a complementary insight into the PL mechanism at the molecular levels for Au NCs in solution.

Toxoplasma gondii infection in pregnant women in China.

Toxoplasmosis, caused by the protozoan parasite Toxoplasma gondii, is one of the most common parasitic infections in humans. Primary infection in pregnant women can be transmitted to the fetus leading to miscarriage or congenital toxoplasmosis. Carefully designed nationwide seroprevalence surveys and case-control studies of risk factors conducted primarily in Europe and America, have shaped our view of the global status of maternal and congenital infection, directing approaches to disease prevention. However, despite encompassing 1 in 5 of the world's population, information is limited on the status of toxoplasmosis in China, partly due to the linguistic inaccessibility of the Chinese literature to the global scientific community. By selection and analysis of studies and data, reported within the last 2 decades in China, this review summarizes and renders accessible a large body of Chinese and other literature and aims to estimate the seroprevalence in Chinese pregnant women. It also reviews the prevalence trends, risk factors, and clinical manifestations. The key findings are (1) the majority of studies show that the overall seroprevalence in Chinese pregnant women is less than 10%, considerably lower than a recently published global analysis; and (2) the few available appropriate studies on maternal acute infection suggested an incidence of 0·3% which is broadly comparable to studies from other countries.

Energy transfer from InGaN quantum wells to Au nanoclusters via optical waveguiding.

We present the first observation of resonance energy transfer from InGaN quantum wells to Au nanoclusters via optical waveguiding. Steady-state and time-resolved photoluminescence measurements provide conclusive evidence of resonance energy transfer and obtain an optimum transfer efficiency of ~72%. A set of rate equations is successfully used to model the kinetics of resonance energy transfer.

[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.

Single fluorescent gold nanoclusters.

Both ensemble and single-molecule measurements were performed to explore the fluorescence properties of Au nanoclusters (NCs). Photoinduced fluorescence enhancement was observed for ensemble NCs in solution, but photobleaching was found at ambient environments. At the single-molecule level, fluorescence blinking and single-step photobleaching were observed. Furthermore, their time-resolved fluorescence shows a single exponential decay with a lifetime of approximately 7 ns and is insensitive to changes in fluorescence intensity. The lifetime distribution is more homogeneous within ensemble Au NCs as compared to CdSe QDs. Therefore, Au NCs have potential applications as nontoxic fluorescent labels for lifetime-based imaging microscopy. However, their low quantum yields and poor photostability are disadvantageous factors, which require further improvement.

[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.