Could S-1-based non-platinum doublet chemotherapy be a new option as a second-line treatment for advanced non-small cell lung cancer patients? A multicenter retrospective study.

Background: For patients who have contraindications to or have failed checkpoint inhibitors, chemotherapy remains the standard second-line option to treat non-oncogene-addicted advanced non-small cell lung cancer (NSCLC). This study aimed to investigate the efficacy and safety of S-1-based non-platinum combination in advanced NSCLC patients who had failed platinum doublet chemotherapy. Methods: During January 2015 and May 2020, advanced NSCLC patients who received S-1 plus docetaxel or gemcitabine after the failure of platinum-based chemotherapy were consecutively retrieved from eight cancer centers. The primary endpoint was progression-free survival (PFS). The secondary endpoint was overall response rate (ORR), disease control rate (DCR), overall survival (OS), and safety. By using the method of matching-adjusted indirect comparison, the individual PFS and OS of included patients were adjusted by weight matching and then compared with those of the docetaxel arm in a balanced trial population (East Asia S-1 Trial in Lung Cancer). Results: A total of 87 patients met the inclusion criteria. The ORR was 22.89% (vs. 10% of historical control, p < 0.001) and the DCR was 80.72%. The median PFS and OS were 5.23 months (95% CI: 3.91-6.55 months) and 14.40 months (95% CI: 13.21-15.59 months), respectively. After matching with a balanced population in the docetaxel arm from the East Asia S-1 Trial in Lung Cancer, the weighted median PFS and OS were 7.90 months (vs. 2.89 months) and 19.37 months (vs. 12.52 months), respectively. Time to start of first subsequent therapy (TSFT) from first-line chemotherapy (TSFT > 9 months vs. TSFT ≤ 9 months) was an independent predictive factor of second-line PFS (8.7 months vs. 5.0 months, HR = 0.461, p = 0.049). The median OS in patients who achieved response was 23.5 months (95% CI: 11.8-31.6 months), which was significantly longer than those with stable disease (14.9 months, 95% CI: 12.9-19.4 months, p < 0.001) or progression (4.9 months, 95% CI: 3.2-9.5 months, p < 0.001). The most common adverse events were anemia (60.92%), nausea (55.17%), and leukocytopenia (33.33%). Conclusions: S-1-based non-platinum combination had promising efficacy and safety in advanced NSCLC patients who had failed platinum doublet chemotherapy, suggesting that it could be a favorable second-line treatment option.

CRISPR-based detection of Helicobacter pylori in stool samples.

BACKGROUND: Noninvasive detection of Helicobacter pylori plays an important role in clinical practice. However, few noninvasive methods have been applied in epidemiological studies due to the requirement for expensive equipment and complicated processes. The aim of this study was to establish a reliable, fast, and inexpensive noninvasive method based on CRISPR-Cas12a technology for the detection of Helicobacter pylori in stool specimens. METHOD: A novel detection method based on CRISPR-Cas12a technology was established and validated with 41 stool specimens collected from Zhujiang Hospital and compared with reliable Helicobacter pylori detection assays, such as the rapid urease test and urea breath test. RESULT: A CRISPR-Cas12a system-based method was established, and its sensitivity and specificity were evaluated. Utilizing a lateral flow biosensor, the limit of detection was 5 copies/µl, and our method could successfully distinguish Helicobacter pylori from other pathogens, suggesting no cross-reactivity with other pathogens. Furthermore, lateral flow biosensor strips were utilized to test stool specimens, which could display the detection results in an accessible way. CONCLUSION: Our CRISPR-Cas12a system-based method successfully detected Helicobacter pylori in stool specimens. It is a rapid, simple, and inexpensive method for the detection and screening of Helicobacter pylori, which makes it a very promising supplemental test. However, its sensitivity and specificity compared with those of the gold standard test still need to be examined.

The Novel Membrane-Associated Auxiliary Factors AuxA and AuxB Modulate ß-lactam Resistance in MRSA by stabilizing Lipoteichoic Acids.

A major determinant of ß-lactam resistance in methicillin-resistant Staphylococcus aureus (MRSA) is the drug insensitive transpeptidase, PBP2a, encoded by mecA. Full expression of the resistance phenotype requires auxiliary factors. Two such factors, auxiliary factor A (auxA, SAUSA300_0980) and B (auxB, SAUSA300_1003), were identified in a screen against mutants with increased susceptibility to ß-lactams in the MRSA strain, JE2. auxA and auxB encode transmembrane proteins, with AuxA predicted to be a transporter. Inactivation of auxA or auxB enhanced ß-lactam susceptibility in community-, hospital- and livestock-associated MRSA strains without affecting PBP2a expression, peptidoglycan cross-linking or wall teichoic acid synthesis. Both mutants displayed increased susceptibility to inhibitors of lipoteichoic acid (LTA) synthesis and alanylation pathways and released LTA even in the absence of ß-lactams. The ß-lactam susceptibility of the aux mutants was suppressed by mutations inactivating gdpP, which was previously found to allow growth of mutants lacking the lipoteichoic synthase enzyme, LtaS. Using the Galleria mellonella infection model, enhanced survival of larvae inoculated with either auxA or auxB mutants was observed compared with the wild-type strain following treatment with amoxicillin. These results indicate that AuxA and AuxB are central for LTA stability and potential inhibitors can be tools to re-sensitize MRSA strains to ß-lactams and combat MRSA infections.

Myocardial ischemia reperfusion injury is alleviated by curcumin-peptide hydrogel via upregulating autophagy and protecting mitochondrial function.

BACKGROUND: Ischemia-reperfusion injury (IRI) is an important factor limiting the success of cardiac reperfusion therapy. Curcumin has a significant cardioprotective effect against IRI, can inhibit ventricular remodeling induced by pressure load or MI, and improve cardiac function. However, the poor water solubility and low bioavailability of curcumin restrict its clinical application. METHODS: In this study, we prepared and evaluated a curcumin-hydrogel (cur-hydrogel) to reduce cardiomyocyte apoptosis and reactive oxygen species formation induced by hypoxia-reoxygenation injury, promote autophagy, and reduce mitochondrial damage by maintaining the phosphorylation of Cx43. RESULTS: Meanwhile, cur-hydrogel can restore cardiac function, inhibit myocardial collagen deposition and apoptosis, and activate JAK2/STAT3 pathway to alleviate myocardial ischemia-reperfusion injury in rats. CONCLUSIONS: The purpose of this study is to elucidate the protective effects of cur-hydrogel on myocardial ischemia-reperfusion injury by regulating apoptosis, autophagy, and mitochondrial injury in vitro and in vivo, which lays a new theoretical and experimental foundation for the prevention and reduction of IRI.

Monoclonal Antibodies Specific to the Extracellular Domain of Histidine Kinase YycG of Staphylococcus epidermidis Inhibit Biofilm Formation.

Staphylococcus epidermidis is frequently associated with biofilm-related infections. Biofilms drastically reduce the efficacy of conventional antibiotics and the host immune system. In S. epidermidis biofilm formation, a major role is played by the YycG/YycF two-component system, and previous findings have indicated that inhibitors targeting the cytoplasmic HATPase_c domain of YycG kinase in S. epidermidis exhibit bactericidal and biofilm-killing activities. Therefore, we hypothesized that monoclonal antibodies (mAbs) against YycG extracellular (YycGex) domain would block the signal transduction and influence the biofilm formation of S. epidermidis. In this study, we screened out two YycGex-specific mAbs showing the highest affinity for the target, mAbs 2F3 and 1H1. These mAbs inhibited S. epidermidis biofilm formation in a dose-dependent manner, and at a concentration of 160 µg/mL, mAbs 2F3 and 1H1 caused 78.3 and 93.1% biofilm reduction, respectively, relative to normal mouse IgG control. When co-cultivated with YycGex mAbs, S. epidermidis cells showed diminished initial-adherence capacity, and the antibody treatment further led to a marked decrease in the synthesis of polysaccharide intercellular adhesin and in the transcriptional level of genes encoding proteins involved in biofilm formation. Lastly, we determined that the epitopes recognized by the two YycGex mAbs are located within aa 59-70 of the YycGex domain. It indicates that the YycGex domain may be a potential candidate as a vaccine for the prevention of S. epidermidis biofilm infections.

Diminishing microbiome richness and distinction in the lower respiratory tract of lung cancer patients: A multiple comparative study design with independent validation.

OBJECTIVES: Current evidence suggests that microorganisms are associated with neoplastic diseases; however, the role of the airway microbiome in lung cancer remains unknown. To investigate the taxonomic profiles of the lower respiratory tract (LRT) microbiome in patients with lung cancer. MATERIALS AND METHODS: BALF samples were collected in a discovery set comprising 150 individuals, including 91 patients with lung cancer, 29 patients with nonmalignant pulmonary diseases and 30 healthy subjects, and an independent validation set including 85 participants. The samples were assessed by metagenomics analysis. Random forest regression analysis was performed to select a diagnostic panel. RESULTS: In the discovery set, richness was reduced in lung cancer patients compared with that in healthy subjects, and the microbiome of patients with nonmalignant diseases resembled that of patients with lung cancer. Interestingly, Bradyrhizobium japonicum was only found in patients with lung cancer, whereas Acidovorax was found in patients with cancer and nonmalignant pulmonary diseases. A microbiota-related diagnostic model consisting of age, pack year of smoking and eleven types of bacteria was built, and the area under the curve (AUC) for discriminating the patients with cancer was 0.882 (95%CI: 0.807-0.957) in the training set and 0.796 (95%CI: 0.673-0.920) in the independent validation set. CONCLUSION: Our study demonstrates that the LRT microbiome richness is diminished in lung cancer patients compared with that in healthy subjects and that microbiota-specific biomarkers may be useful for diagnosing patients for whom lung biopsy is not feasible.

Vibrio vulnificus meningoencephalitis in a patient with thalassemia and a splenectomy.

Vibrio vulnificus usually causes wound infection, gastroenteritis, and septicemia. However, it is a rare conditional pathogen causing meningoencephalitis. We report a case of a young, immunocompromised man presenting with severe sepsis after exposure to sea water and consumption of seafood. The patient subsequently developed meningoencephalitis, and Vibrio vulnificus was isolated from his blood culture. The sequence was confirmed by Next-generation sequencing of a sample of cerebrospinal fluid, as well as from a bacteria culture. After the pathogen was detected, the patient was treated with ceftriaxone, doxycycline, and moxifloxacin for 6 weeks, which controlled his infection. In this case, we acquired his clinical and dynamic MRI presentations, which were never reported. Physicians should consider Vibrio vulnificus infections when they see a similar clinical course, brain CT and MRI findings, susceptibility factors and recent seafood ingestion or exposure to seawater. Due to high mortality, the early diagnosis and treatment of Vibrio vulnificus infections are crucial. Next-generation sequencing was found to be useful for diagnosis.

Anti-bacterial and Anti-biofilm Evaluation of Thiazolopyrimidinone Derivatives Targeting the Histidine Kinase YycG Protein of Staphylococcus epidermidis.

Staphylococcus epidermidis is one of the most important opportunistic pathogens in nosocomial infections. The main pathogenicity associated with S. epidermidis involves the formation of biofilms on implanted medical devices, biofilms dramatically decrease the efficacy of conventional antibiotics and the host immune system. This emphasizes the urgent need for designing novel anti-staphylococcal biofilm agents. Based on the findings that compound 5, targeting the histidine kinase domain of S. epidermidis YycG, possessed bactericidal activity against staphylococci, 39 derivatives of compound 5 with intact thiazolopyrimidinone core structures were newly designed, 7 derivatives were further screened to explore their anti-bacterial and anti-biofilm activities. The seven derivatives strongly inhibited the growth of S. epidermidis and Staphylococcus aureus in the minimal inhibitory concentration range of 1.56-6.25 µM. All the derivatives reduced the proportion of viable cells in mature biofilms. They all displayed low cytotoxicity on mammalian cells and were not hemolytic to human erythrocytes. The biofilm inhibition activities of four derivatives (H5-32, H5-33, H5-34, and H5-35) were further investigated under shearing forces, they all led to significant decreases in the biofilm formation of S. epidermidis. These results were suggestive that the seven derivatives of compound 5 have the potential to be developed into agents for eradicating biofilm-associated infections.

[Concept and Implementation of ECG Monitoring for Whole-course of Pre-hospital Emergency].

In pre-hospital emergency, it's essential to immediate recognize cardiac arrest, and use real-time ECG monitoring for patients. We propose a concept of whole-course ECG monitoring and implementation in pre-hospital emergency, and design a portable pre-hospital ECG monitor (Pre-ECG). There are two working modes in Pre-ECG, i.e., rapid detection and continuous monitoring modes. In rapid detection mode, ECG waves and heart rate of patients can be displayed in a few seconds by using metal electrodes, which helps to understand the status of patients' cardiac electrical activity. After connecting lead wire to the Pre-ECG, it can automatically switch to working in continous monitoring mode. At this time, ECG waves and heart rate can be displayed in real time, and give an alarm for abnormalities of heart rate, which can well meet the requirement from transfer process of patients. Moreover, all ECG data derived from the two modes can be stored permanently in TranFlash card, which can be printed via bluetooth printer, be used for remote medical consultation through the internet, or be reserved as legal evidence and academic research materials.

Erratum: Antibacterial and anti-biofilm activities of thiazolidione derivatives against clinical staphylococcus strains.

[This corrects the article DOI: 10.1038/emi.2015.1.].

Antibacterial and anti-biofilm activities of thiazolidione derivatives against clinical staphylococcus strains.

Both Staphylococcus aureus and Staphylococcus epidermidis can form biofilms on natural surfaces or abiotic surfaces, such as medical implants, resulting in biofilm-associated diseases that are refractory to antibiotic treatment. We previously reported a promising antibacterial compound (Compound 2) and its derivatives with bactericidal and anti-biofilm activities against both S. epidermidis and S. aureus. We have further evaluated the antibacterial activities of four Compound 2 derivatives (H2-38, H2-39, H2-74 and H2-81) against 163 clinical strains of S. epidermidis and S. aureus, including methicillin-susceptible and methicillin-resistant strains, as well as biofilm-forming and non-biofilm-forming strains. The four derivatives inhibited the planktonic growth of all of the clinical staphylococcal isolates, including methicillin-resistant S. aureus and methicillin-resistant S. epidermidis and displayed bactericidal activities against both immature (6 h) and mature (24 h) biofilms formed by the strong biofilm-forming strains. The derivatives, which all target YycG, will help us to develop new antimicrobial agents against multidrug-resistant staphylococci infections and biofilm-associated diseases.

The occurrence and ecological risk assessment of phthalate esters (PAEs) in urban aquatic environments of China.

Phthalate esters (PAEs) are widely used in the manufacturing of plastics, and the demand for PAEs has grown rapidly, especially in China. This trend will lead to much more environmental PAE contamination. PAEs are listed as priority substances in the European Union and are therefore subject to ecological risk assessments. This paper reviews the literature concerning the pollution status of PAEs and their ecological risk to aquatic environments. Risk quotients (RQs) based on the predicted no effect concentration and PAE concentrations in aquatic environments demonstrated significant (10 ≤ RQ < 100) or expected (RQ ≥ 100) potential adverse effects for algae, Daphnia, and fish in aquatic environments near PAE-based industrial and urban areas. Thus, the ecological risk of PAEs in Chinese aquatic environments should be considered, especially in areas where commercial plastics are produced.

Staphylococcus epidermidis SrrAB regulates bacterial growth and biofilm formation differently under oxic and microaerobic conditions.

SrrAB expression in Staphylococcus epidermidis strain 1457 (SE1457) was upregulated during a shift from oxic to microaerobic conditions. An srrA deletion (ΔsrrA) mutant was constructed for studying the regulatory function of SrrAB. The deletion resulted in retarded growth and abolished biofilm formation both in vitro and in vivo and under both oxic and microaerobic conditions. Associated with the reduced biofilm formation, the ΔsrrA mutant produced much less polysaccharide intercellular adhesion (PIA) and showed decreased initial adherence capacity. Microarray analysis showed that the srrA mutation affected transcription of 230 genes under microaerobic conditions, and 51 genes under oxic conditions. Quantitative real-time PCR confirmed this observation and showed downregulation of genes involved in maintaining the electron transport chain by supporting cytochrome and quinol-oxidase assembly (e.g., qoxB and ctaA) and in anaerobic metabolism (e.g., pflBA and nrdD). In the ΔsrrA mutant, the expression of the biofilm formation-related gene icaR was upregulated under oxic conditions and downregulated under microaerobic conditions, whereas icaA was downregulated under both conditions. An electrophoretic mobility shift assay further revealed that phosphorylated SrrA bound to the promoter regions of icaR, icaA, qoxB, and pflBA, as well as its own promoter region. These findings demonstrate that in S. epidermidis SrrAB is an autoregulator and regulates biofilm formation in an ica-dependent manner. Under oxic conditions, SrrAB modulates electron transport chain activity by positively regulating qoxBACD transcription. Under microaerobic conditions, it regulates fermentation processes and DNA synthesis by modulating the expression of both the pfl operon and nrdDG.

Biological evaluation of halogenated thiazolo[3,2-a]pyrimidin-3-one carboxylic acid derivatives targeting the YycG histidine kinase.

With an intention to potent inhibitors of YycG histidine kinase, a series of halogenated thiazolo[3,2-a]pyrimidin-3-one carboxylic acid derivatives were synthesized and evaluated for their antibacterial, antibiofilm and hemolytic activities. The majority of the compounds showed good activity against Staphylococcus epidermidis and Staphylococcus aureus, with MIC values of 1.56-6.25 µM, simultaneously presented promising antiobifilm activity against S. epidermidis ATCC35984 at 50 µM. The test of inhibitory activity on YycG kinase suggested the antibacterial activities of these derivatives are based on inhibiting the enzyme activity of the YycG HK domain. The hemolytic activity test suggested these compounds exhibited in vitro antibacterial activity at non-hemolytic concentrations.

Efficacy of novel antibacterial compounds targeting histidine kinase YycG protein.

Treating staphylococcal biofilm-associated infections is challenging. Based on the findings that compound 2 targeting the HK domain of Staphylococcus epidermidis YycG has bactericidal and antibiofilm activities against staphylococci, six newly synthesized derivatives were evaluated for their antibacterial activities. The six derivatives of compound 2 inhibited autophosphorylation of recombinant YycG' and the IC50 values ranged from 24.2 to 71.2 µM. The derivatives displayed bactericidal activity against planktonic S. epidermidis or Staphylococcus aureus strains in the MIC range of 1.5-3.1 µM. All the derivatives had antibiofilm activities against the 6- and 24-h biofilms of S. epidermidis. Compared to the prototype compound 2, they had less cytotoxicity for Vero cells and less hemolytic activity for human erythrocytes. The derivatives showed antibacterial activities against clinical methicillin-resistant staphylococcal isolates. The structural modification of YycG inhibitors will assist the discovery of novel agents to eliminate biofilm infections and multidrug-resistant staphylococcal infections.

Thiazolidione derivatives targeting the histidine kinase YycG are effective against both planktonic and biofilm-associated Staphylococcus epidermidis.

AIM: To evaluate the efficacies of six derivatives of Compound 2, a novel YycG histidine kinase inhibitor with the thiazolidione core structure in the treatment of medical device-related biofilm infections. METHODS: The minimal inhibitory concentration (MIC) of the derivatives was determined using the macrodilution broth method, and the minimal bactericidal concentration (MBC) was obtained via sub-culturing 100 µL from each negative tube from the MIC assay onto drug-free Mueller-Hinton agar plates. Biofilm-killing effect for immature (6 h-old) biofilms was examined using a semiquantitative plate assay, and the effect on mature (24 h-old) biofilms was observed under a confocal laser scanning microscope (CLSM). RESULTS: The derivatives potently suppressed the growth of Staphylococcus epidermidis. The MIC values of the derivatives H2-10, H2-12, H2-20, H2-29, H2-27, and H2-28 on S epidermidis ATCC 35984 were 24.3, 6.5, 6.2, 3.3, 3.1, and 1.5 µg/mL, respectively. The MBC values of these derivatives were 48.6, 52.2, 12.4, 52.6, 12.4, and 6.2 µg/mL, respectively. The derivatives killed all bacteria in immature (6 h-old) biofilms and eliminated the biofilm proliferation. The derivatives also displayed strong bactericidal activities toward cells in mature (24 h-old) biofilms, whereas they showed low cytotoxicity and hemolytic activity toward Vero cells and human erythrocytes. CONCLUSION: The bactericidal and biofilm-killing activities of the new anti-YycG compounds were significantly better than the parent Compound 2.

Enhancement of vancomycin activity against biofilms by using ultrasound-targeted microbubble destruction.

Treating biofilm infections on implanted medical devices is formidable, even with extensive antibiotic therapy. The aim of this study was to investigate whether ultrasound (US)-targeted microbubble (MB) destruction (UTMD) could enhance vancomycin activity against Staphylococcus epidermidis RP62A biofilms. Twelve-hour biofilms were treated with vancomycin combined with UTMD. The vancomycin and MB (SonoVue) were used at concentrations of 100 µg/ml and 30% (vol/vol), respectively, in studies in vitro. After US exposure (0.08 MHz, 1.0 W/cm(2), 50% duty cycle, and 10-min duration), the biofilms were cultured at 37 °C for another 12 h. The results showed that many micropores were found in biofilms treated with vancomycin combined with UTMD. Biofilm densities (A(570) values) and the viable counts of S. epidermidis recovered from the biofilm were significantly decreased compared with those of any other groups. Furthermore, the highest percentage of dead cells was found, using confocal laser scanning microscopy, in the biofilm treated with vancomycin combined with UTMD. The viable counts of bacteria in biofilms in an in vivo rabbit model also confirmed the enhanced effect of vancomycin combined with UTMD. UTMD may have great potential for improving antibiotic activity against biofilm infections.

Monoclonal antibodies against accumulation-associated protein affect EPS biosynthesis and enhance bacterial accumulation of Staphylococcus epidermidis.

Because there is no effective antibiotic to eradicate Staphylococcus epidermidis biofilm infections that lead to the failure of medical device implantations, the development of anti-biofilm vaccines is necessary. Biofilm formation by S. epidermidis requires accumulation-associated protein (Aap) that contains sequence repeats known as G5 domains, which are responsible for the Zn(2+)-dependent dimerization of Aap to mediate intercellular adhesion. Antibodies against Aap have been reported to inhibit biofilm accumulation. In the present study, three monoclonal antibodies (MAbs) against the Aap C-terminal single B-repeat construct followed by the 79-aa half repeat (AapBrpt1.5) were generated. MAb(18B6) inhibited biofilm formation by S. epidermidis RP62A to 60% of the maximum, while MAb(25C11) and MAb(20B9) enhanced biofilm accumulation. All three MAbs aggregated the planktonic bacteria to form visible cell clusters. Epitope mapping revealed that the epitope of MAb(18B6), which recognizes an identical area within AapBrpt constructs from S. epidermidis RP62A, was not shared by MAb(25C11) and MAb(20B9). Furthermore, all three MAbs were found to affect both Aap expression and extracellular polymeric substance (EPS, including extracellular DNA and PIA) biosynthesis in S. epidermidis and enhance the cell accumulation. These findings contribute to a better understanding of staphylococcal biofilm formation and will help to develop epitope-peptide vaccines against staphylococcal infections.