Real-world effectiveness of molnupiravir, azvudine and paxlovid against mortality and viral clearance among hospitalized patients with COVID-19 infection during the omicron wave in China: A retrospective cohort study.

OBJECTIVES: In this retrospective cohort study, we aimed to assess clinical effectiveness and viral clearance following the use of molnupiravir, azvudine and paxlovid in hospitalized patients with COVID-19 in China dominated by the omicron BA.5.2 and BF.7 subvariant of SARS-CoV-2. METHODS: Enrolled patients were assigned to the molnupiravir group or the azvudine group or the paxlovid group or the control group (not taking any antiviral drugs). The primary outcome of the cohort study was viral clearance and viral burden rebound after treatment and the secondary outcome was 28-day all-cause mortality. The four groups were propensity score-matched (1:1). We plotted viral load trends for each antiviral drug intervention using locally weighted regression (LOWESS) smoothed data. Multivariate logistic regression (stepwise algorithm) models were used to determine any risk factors for 28-day mortality. RESULTS: Of the 1537 patients receiving any treatment, 886 (57.6 %) received molnupiravir, 390 (25.4 %) received azvudine, 94 (6.1 %) received paxlovid, and 167 (10.9 %) did not use any antiviral drugs. Our data analysis showed that age (OR = 1.05, 95 % CI: 1.03-1.07, P < 0.001), Charlson comorbidty index (OR = 1.32, 95 % CI: 1.18-1.48, P < 0.001), severity of COVID-19 (P < 0.001), gamma globulin (OR = 2.04, 95 % CI: 1.03-3.99, P = 0.039) and corticosteroids use (OR = 2.3, 95 % CI: 1.19-4.69, P = 0.017) were independent prognostic factors for 28-day mortality in COVID-19 patients. After propensity score matching (PSM), the paxlovid recipients (OR = 0.22, 95 % CI: 0.05-0.83, P = 0.036) or azvudine recipients (OR = 0.27, 95 % CI: 0.07-0.91, P = 0.046) had lower 28-day mortality compared to their matched controls. Viral rebound occurred in the control group around days 9-16, while no viral rebound was found in any of the three oral antiviral groups. We found that molnupiravir group performed comparably in terms of the rate of nucleic acid conversion negative compared with the paxlovid group, while azvudine group performed slightly worse compared with the paxlovid group or molnupiravir group. CONCLUSIONS: In our retrospective cohort of hospitalized patients with COVID-19 during the wave of omicron strain, the molnupiravir, paxlovid and azvudine recipients showed a faster and more stable decrease in viral load and rare virus rebound in response to antiviral treatments when compared to the controls. The study supported that initiation treatment with paxlovid and azvudine was associated with significantly lower risk of all-cause death within 28 days.

Improvement effects of cyclic peptides from Annona squamosa on cognitive decline in neuroinflammatory mice.

Cyclic peptides can resist enzymatic hydrolysis to pass through the intestine barrier, which may reduce the risk of mild cognition decline. But evidence is lacking on whether they work by alleviating neuroinflammation. A cylic peptide from Annona squamosa, Cylic(PIYAG), was biologically evaluated in vivo and in vitro. Cylic(PIYAG) enhanced the spatial memory ability of LPS-induced mice. And treatment with Cylic(PIYAG) markedly reduced the iNOS, MCP-1, TNF-α, and gp91phox expression induced by LPS. Cylic(PIYAG, 0.01, 0.05 and 0.2 µM) could significantly reduce the protein expression level of COX-2 and iNOS (P < 0.05) in BV2 cells. The concentration of Cylic(PIYAG) in blood reached a peak of 3.64 ± 1.22 µg/ml after intragastric administration in 1 h. And fluorescence microscope shows that Cylic(PIYAG) mainly locates and may play an anti-inflammatory role in the cytoplasm of microglia. This study demonstrates that the peptidic can prevent microglia activation, decrease the inflammatory reaction, improve the cognition of LPS-induced mice. Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-023-01441-8.

The Role of Side Chains and Hydration on Mixed Charge Transport in n-Type Polymer Films.

Introducing ethylene glycol (EG) side chains to a conjugated polymer backbone is a well-established synthetic strategy for designing organic mixed ion-electron conductors (OMIECs). However, the impact that film swelling has on mixed conduction properties has yet to be scoped, particularly for electron-transporting (n-type) OMIECs. Here, the authors investigate the effect of the length of branched EG chains on mixed charge transport of n-type OMIECs based on a naphthalene-1,4,5,8-tetracarboxylic-diimide-bithiophene backbone. Atomic force microscopy (AFM), grazing-incidence wide-angle X-ray scattering (GIWAXS), and scanning tunneling microscopy (STM) are used to establish the similarities between the common-backbone films in dry conditions. Electrochemical quartz crystal microbalance with dissipation monitoring (EQCM-D) and in situ GIWAXS measurements reveal stark changes in film swelling properties and microstructure during electrochemical doping, depending on the side chain length. It is found that even in the loss of the crystallite content upon contact with the aqueous electrolyte, the films can effectively transport charges and that it is rather the high water content that harms the electronic interconnectivity within the OMIEC films. These results highlight the importance of controlling water uptake in the films to impede charge transport in n-type electrochemical devices.

Rapid detection of clarithromycin resistance in clinical samples of nontuberculous mycobacteria by nucleotide MALDI-TOF MS.

The multidrug resistance of nontuberculous mycobacteria (NTM) poses a significant therapeutic challenge. Rapid and reliable drug susceptibility testing is urgently needed for evidence-based treatment decision, especially for macrolides. This study evaluated the utility of nucleotide matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (NMTMS) in detecting clarithromycin resistance. Sixty-four clinical isolates were identified to species by NMTMS, and mutations associated with clarithromycin resistance were detected. Twenty-three M. abscessus (MAB) isolates and 30 M. intracellulare isolates (including M. intracellulare alone and M. intracellulare in combination with other SGM species) were included for analysis. The predictive sensitivity of NMTMS in detecting clarithromycin resistance was 82.35% (95% CI, 56.57% to 96.20%), with an AUC of 0.89 (95% CI, 0.77 to 0.96) in all MAB and M. intracellulare (n = 53), and up to 93.33% (95% CI, 68.05% to 99.83%) in MAB alone (n = 23). The assay provides a rapid, high-throughput, and highly sensitive tool for detecting clarithromycin resistance in NTM, especially in MAB. Optimization of the panel is necessary to enhance diagnostic accuracy.

A 10-m annual grazing intensity dataset in 2015-2021 for the largest temperate meadow steppe in China.

Mapping grazing intensity (GI) using satellites is crucial for developing adaptive utilization strategies according to grassland conditions. Here we developed a monitoring framework based on a paired sampling strategy and the classification probability of random forest algorithm to produce annual grazing probability (GP) and GI maps at 10-m spatial resolution from 2015 to 2021 for the largest temperate meadow in China (Hulun Buir grasslands), by harmonized Landsat 7/8 and Sentinel-2 images. The GP maps used values of 0-1 to present detailed grazing gradient information. To match widely used grazing gradients, annual GI maps with ungrazed, moderately grazed, and heavily grazed levels were generated from the GP dataset with a decision tree. The GI maps for 2015-2021 had an overall accuracy of more than 0.97 having significant correlations with the statistical data at city (r = 0.51) and county (r = 0.75) scales. They also effectively captured the GI gradients at site scale (r = 0.94). Our study proposed a monitoring approach and presented annual 10-m grazing information maps for sustainable grassland management.

Transmission of fluoroquinolones resistance among multidrug-resistant tuberculosis in Shanghai, China: a retrospective population-based genomic epidemiology study.

Fluoroquinolones (FQ) are essential for the treatment of multidrug-resistant tuberculosis (MDR-TB). The FQ resistance (FQ-R) rate in MDR-TB in China and its risk factors remain poorly understood. We conducted a retrospective, population-based genomic epidemiology study of MDR-TB patients in Shanghai, China, from 2009 to 2018. A genomic cluster was defined as strains with genetic distances ≤ 12 single nucleotide polymorphisms. The transmitted FQ-R was defined as the same FQ resistance-conferring mutations shared by ≥ 2 strains in a genomic cluster. We used multivariable logistic regression analysis to identify the risk factors for drug resistance. Among the total 850 MDR-TB patients included in the study, 72.8% (619/850) were male, the median age was 39 (interquartile range 28, 55) years, 52.7% (448/850) were migrants, and 34.5% (293/850) were previously treated patients. Most of the MDR-TB strains belong to the Beijing lineage (91.7%, 779/850). Overall, the genotypic resistance rate of FQ was 34.7% (295/850), and 47.1% (139/295) FQ-R patients were in genomic clusters, of which 98 (33.2%, 98/295) were presumed as transmitted FQ-R. Patients with treatment-naïve (aOR = 1.84; 95% CI: 1.09, 3.16), diagnosed in a district-level hospital (aOR = 2.69; 95% CI: 1.56, 4.75), and streptomycin resistance (aOR = 3.69; 95% CI: 1.65, 9.42) were significantly associated with the transmission of FQ-R. In summary, the prevalence of FQ-R among MDR-TB patients was high in Shanghai, and at least one-third were transmitted. Enforced interventions including surveillance of FQ drug susceptibility testing and screening among MDR-TB before initiation of treatment were urgently needed.

Novel small-molecule compound YH7 inhibits the biofilm formation of Staphylococcus aureus in a sarX-dependent manner.

The emergence of antibiotic-resistant and biofilm-producing Staphylococcus aureus isolates presents major challenges for treating staphylococcal infections. Biofilm inhibition is an important anti-virulence strategy. In this study, a novel maleimide-diselenide hybrid compound (YH7) was synthesized and demonstrated remarkable antimicrobial activity against methicillin-resistant S. aureus (MRSA) and methicillin-susceptible S. aureus (MSSA) in both planktonic cultures and biofilms. The minimum inhibitory concentration (MIC) of YH7 for S. aureus isolates was 16 µg/mL. Quantification of biofilms demonstrated that the sub-MIC (4 µg/mL) of YH7 significantly inhibits biofilm formation in both MSSA and MRSA. Confocal laser scanning microscopy analysis further confirmed the biofilm inhibitory potential of YH7. YH7 also significantly suppressed bacterial adherence to A549 cells. Moreover, YH7 treatment significantly inhibited S. aureus colonization in nasal tissue of mice. Preliminary mechanistic studies revealed that YH7 exerted potent biofilm-suppressing effects by inhibiting polysaccharide intercellular adhesin (PIA) synthesis, rather than suppressing bacterial autolysis. Real-time quantitative PCR data indicated that YH7 downregulated biofilm formation-related genes (clfA, fnbA, icaA, and icaD) and the global regulatory gene sarX, which promotes PIA synthesis. The sarX-dependent antibiofilm potential of YH7 was validated by constructing S. aureus NCTC8325 sarX knockout and complementation strains. Importantly, YH7 demonstrated a low potential to induce drug resistance in S. aureus and exhibited non-toxic to rabbit erythrocytes, A549, and BEAS-2B cells at antibacterial concentrations. In vivo toxicity assays conducted on Galleria mellonella further confirmed that YH7 is biocompatible. Overall, YH7 demonstrated potent antibiofilm activity supports its potential as an antimicrobial agent against S. aureus biofilm-related infections. IMPORTANCE Biofilm-associated infections, characterized by antibiotic resistance and persistence, present a formidable challenge in healthcare. Traditional antibacterial agents prove inadequate against biofilms. In this study, the novel compound YH7 demonstrates potent antibiofilm properties by impeding the adhesion and the polysaccharide intercellular adhesin production of Staphylococcus aureus. Notably, its exceptional efficacy against both methicillin-resistant and methicillin-susceptible strains highlights its broad applicability. This study highlights the potential of YH7 as a novel therapeutic agent to address the pressing issue of biofilm-driven infections.

Emergence of KPC-2 and NDM-5-coproducing hypervirulent carbapenem-resistant Klebsiella pneumoniae with high-risk sequence types ST11 and ST15.

The emergence of Klebsiella pneumoniae carbapenemase-2 (KPC-2) and New Delhi metallo-ß-lactamase (NDM)-coproducing hypervirulent carbapenem-resistant Klebsiella pneumoniae (KPC-2-NDM-hv-CRKP) poses a certain threat to public health. Currently, only a few sporadic reports of such double-positive hv-CRKPs were available. In this study, we isolated two KPC-2-NDM-5-hv-CRKPs from elderly patients with serious underlying diseases and poor prognoses. We found both FK3122 and FK3127 were typical multidrug-resistant (MDR) isolates, exhibiting high-level resistance to both carbapenems and novel ß-lactamase inhibitors ceftazidime/avibactam. Notably, FK3122 is even resistant to cefiderocol due to multiple blaNDM-5 elements. Besides the MDR phenotype, A549 human lung epithelial cells and Galleria mellonella infection model all indicated that FK3122 and FK3127 were highly pathogenic. According to the whole-genome sequencing analysis, we observed over 10 resistant elements, and the uncommon co-existence of blaKPC-2, blaNDM-5, and virulence plasmids in both two isolates. Both virulence plasmids identified in FK3122 and FK3127 shared a high identity with classical virulence plasmid pK2044, harboring specific hypervirulent factors: rmpA and iuc operon. We also found that the resistance and virulence plasmids in FK3127 could not only be transferred to Escherichia coli EC600 independently but also together as a co-transfer, which was additionally confirmed by the S1-pulsed-field gel electrophoresis plasmid profile. Moreover, polymorphic mobile genetic elements were found surrounding resistance genes, which may stimulate the mobilization of resistance genes and result in the duplication of these elements. Considering the combination of high pathogenicity, limited therapy options, and easy transmission of KPC-2-NDM-5-hv-CRKP, our study emphasizes the need for underscores the imperative for ongoing surveillance of these pathogens.IMPORTANCEHypervirulent Klebsiella pneumoniae drug resistance has increased gradually with the emergence of carbapenem-resistant hypervirulent K. pneumoniae (hv-CRKP). However, little information is available on the virulence characteristics of the New Delhi metallo-ß-lactamase (NDM) and Klebsiella pneumoniae carbapenemase-2 (KPC-2) co-producing K. pneumoniae strains. In this study, we obtained two KPC-2-NDM-hv-CRKPs from elderly patients, each with distinct capsule types and sequence types: ST11-KL64 and ST15-KL24; these ST-type lineages are recognized as classical multidrug-resistant (MDR) K. pneumoniae. We found these KPC-2-NDM-hv-CRKPs were not only typical MDR isolates, including resistance to ceftazidime/avibactam and cefiderocol, but also displayed exceptionally high levels of pathogenicity. In addition, these high-risk factors can also be transferred to other isolates. Consequently, our study underscores the need for ongoing surveillance of these isolates due to their heightened pathogenicity, limited therapeutic options, and potential for easy transmission.

Two-pronged microenvironmental modulation of metal-oxidase cascade catalysis and metabolic intervention for synergistic tumor immunotherapy.

Immunotherapy is an emerging treatment modality for tumors after surgery, radiotherapy, and chemotherapy. Despite the potential for eliminating primary tumor cells and depressing cancer metastasis, immunotherapy has huge challenges including low tumor immunogenicity and undesirable immunosuppressive tumor microenvironment (TME). Herein, the two-pronged microenvironmental modulation nanoplatform is developed to overcome these limitations. Specifically, hollow mesoporous MnO2 (HM) nanoparticles with pH responsive property are prepared and modified with glucose oxidase (GOX) by amide bond, which are further loaded with a potent glutaminase inhibitor CB839 to obtain HM-GOX/CB839. Under the low pH values in TME, HM was disintegrated, thereby releasing Mn2+, GOX and CB839. On the one hand, Mn2+ can convert H2O2 that increased by GOX catalysis in tumors into highly toxic hydroxyl radicals (•OH) and further induce immunogenic cell death (ICD) through the metal-oxidase cascade catalytic reaction, enhancing immunogenicity. On the other hand, GOX and CB839 can block glycolytic and glutamine metabolism pathways, respectively, which effectively reduce the number of immunosuppressive cells and reshape TME, improving anti-tumor immune efficacy. It is demonstrated that HM-GOX/CB839 can effectively activate the body's immunity and inhibit tumor growth and metastasis, providing a potential strategy for comprehensive tumor therapy. STATEMENT OF SIGNIFICANCE: Integrated microenvironmental modulation of metal-oxidase cascade catalysis and metabolic intervention offers a potential avenue for tumor immunotherapy. Under this premise, we constructed a two-pronged microenvironmental modulation nanoplatform (HM-GOX/CB839). On the one hand, the metal oxidase cascade could catalyze the generation of hydroxyl radicals (•OH) and induce immunogenic cell death (ICD), enhancing immunogenicity; on the other hand, metabolic intervention reprogrammed tumor microenvironment to relieve immunosuppression and thereby enhancing anti-tumor immune response. The resulting data demonstrated that HM-GOX/CB839 effectively inhibited tumor growth and metastasis, providing therapeutic potential for cancer immunotherapy.

Bedaquiline, Delamanid, Linezolid, Clofazimine, and Capreomycin MIC Distributions for Drug Resistance Mycobacterium tuberculosis in Shanghai, China.

Background: New antituberculosis drugs have recently been approved for the treatment of multidrug-resistant tuberculosis TB (MDR-TB). We aimed to describe the distributions of bedaquiline, delamanid, linezolid, clofazimine, and capreomycin MIC values for M. tuberculosis. Methods: M. tuberculosis clinical isolates were originally isolated from 2020 to 2021 from 1452 different pulmonary tuberculosis patients of the Shanghai Pulmonary Hospital in China. The drug susceptibility testing was performed using the Sensititre custom plates (SHTBMY) (TREK Diagnostic Systems, Thermo Fisher Scientific In., USA) consisting of a 96-well microtitre plate containing 4 (bedaquiline, delamanid, clofazimine, capreomycin) antimicrobial agents. MICs were determined for linezolid using a microdilution method. Results: Based on the latest definitions, 156 (10.74%) were MDR-TB, 93 (6.40%) were pre-XDR-TB, and 27 (1.86%) were XDR-TB. The rate of BDQ resistance in cases of MDR-TB was 7.69%, while it was observed to be 10.75% in cases of pre-XDR-TB, and significantly higher at 37.04% in cases of XDR-TB. The lowest rate of drug resistance against M. tuberculosis was DLM (0.14%). For LZD, 11 (0.76%) clinical isolates were resistant, based on the CLSI breakpoint of 1µg/mL. The five strains with a MIC value of >32 for LZD resistance were XDR-TB isolates. Among all MDR, pre-XDR, and XDR isolates tested, LZD' MIC50 increased from 0.25 and 0.5 to 1µg/mL. The MIC90 value of LZD against XDR-TB isolates was 32µg/mL. For CFZ, six isolates with elevated MICs of ≥2µg/mL. CFZ's MIC50 and MIC90 values in all isolates were 0.12µg/mL and 0.25µg/mL, respectively. Conclusion: The study findings indicate that BDQ, DLM, CFZ, and LZD may exhibited excellent in vitro activity against MDR-TB isolates. Detection of resistance to BDQ and LZD was alarming for XDR-TB isolates. It is necessary to perform universal drug sensitivity testing for M. tuberculosis, especially MDR-TB and XDR-TB patients.

Performance of the MeltPro TB assay as initial test for diagnosis of pulmonary tuberculosis with drug-resistance detection.

BACKGROUND: The MeltPro TB assay (MeltPro) is a molecular rapid diagnostic test designed for detecting resistance to antituberculosis drugs. However, the performance of MeltPro as an initial diagnostic test for simultaneously detecting the presence of Mycobacterium tuberculosis (MTB) and drug resistance has not been evaluated. This study aims to assess the performance of MeltPro as initial diagnostic test for simultaneous detection of MTB and drug resistance in clinical samples from patients with presumptive pulmonary tuberculosis (PTB). METHODS: A retrospective analysis was conducted on 1283 patients with presumptive PTB from two clinical centers, out of which 875 were diagnosed with PTB. The diagnostic accuracy of MeltPro, Xpert MTB/RIF (Xpert), and MGIT 960 for PTB detection was evaluated. Rifampicin (RIF), isoniazid (INH), ethambutol (EMB), streptomycin (STR), and fluoroquinolone (FQ) resistance were detected using MeltPro, with Xpert and/or the broth microdilution plate method (MYCOTB) results as references. RESULTS: For the diagnosis of PTB, MeltPro showed a sensitivity of 69.0%, which was similar to Xpert (72.7%; P > 0.05) and higher than MGIT (58.1%; P < 0.001). The specificity of MeltPro was 97.1%, similar to Xpert (98.0%; P > 0.05). In smear-negative patients, MeltPro's sensitivity was 50.9%, similar to Xpert (56.5%; P > 0.05), and higher than MGIT (33.1%; P < 0.001). Based on Xpert and/or MYCOTB results, MeltPro exhibited a sensitivity and specificity of 98.3% and 99.2%, respectively, for detecting RIF resistance. Based on MYCOTB results, MeltPro's sensitivity for detecting resistance to INH, EMB, STR, and FQ was 96.4%, 89.1%, 97.5%, and 90.3%, respectively, with specificities of 96.0%, 96.0%, 95.2%, and 99.4%, respectively. CONCLUSION: The MeltPro TB assay could potentially be an effective alternative as the initial test for rapid diagnosis of PTB with drug-resistance detection in clinical practice.

Assessment of the Cepheid 3-gene Host Response Fingerstick Blood Test (MTB-HR) on rapid diagnosis of tuberculosis.

ABSTRACTThe World Health Organization has identified high-priority target product profiles for new TB diagnostics which include rapid biomarker-based, non-sputum-based diagnostic testing, using an easily accessible sample. The Cepheid 3-gene Host Response Fingerstick Blood Prototype Test (MTB-HR) quantifies relative mRNA levels of a 3-gene signature (GBP5, DUSP3, and KLF2) from a whole-blood sample on the GeneXpert platform. The objective of the present study was to evaluate the performance of the MTB-HR to distinguish between active tuberculosis (ATB), latent Mycobacterium tuberculosis infection (LTBI), other pulmonary diseases, and healthy volunteers at a tertiary care centre. Among 653 participants enrolled in this study, 192 were diagnosed as having ATB, and the remaining 461 were classified as non-ATB, including 137 cases of LTBI, 224 cases of other pulmonary diseases, and 100 healthy volunteers. The corresponding AUCs of the MTB-HR in distinguishing untreated ATB from non-ATB, LTBI, other pulmonary diseases, and healthy volunteers were 0.814 (95% CI, 0.760-0.868, sensitivity 76.1%, specificity 71.6%), 0.739 (95% CI, 0.667-0.812, sensitivity 59.7%, specificity 78.1%), 0.825 (95% CI, 0.770-0.880, sensitivity 82.1%, specificity 65.6%), 0.892 (95% CI, 0.839-0.945, sensitivity 76.1%, specificity 88.0%), respectively. When only samples with TAT of less than 1 h were included, the AUC of the MTB-HR in distinguishing untreated ATB from non-ATB was largest, 0.920 (95% CI, 0.822-1.000, sensitivity 81.3%, specificity 87.7%). In conclusion, the MTB-HR assay shows potential as a rapid, blood-based screening and triage test for ATB, especially for untreated ATB, with the advantage of increased diagnostic yield since blood is more readily available.

EBUS-GS with the GeneXpert MTB/RIF assay for diagnosis of Mycobacterium tuberculosis infection of isolated pulmonary nodules.

OBJECTIVE: Investigate the use of endobronchial ultrasonography with a guide sheath (EBUS-GS) combined with Gene Xpert MTB/RIF (Xpert) for diagnosis of Mycobacterium tuberculosis (MTB) infection in isolated pulmonary nodules. METHODS: Patients who had isolated pulmonary nodules and unknown diagnoses at our institution from October 2020 to December 2021 were prospectively examined using EBUS-GS and Xpert. The diagnostic values of using EBUS-GS or bronchoalveolar lavage fluid (BALF) with acid-fast staining, MGIT 960 culture, pathological examination, and Xpert for isolated pulmonary nodules caused by MTB infection were compared using receiver operating characteristic (ROC) analysis. RESULTS: There were 135 patients, 64 with isolated pulmonary tuberculomas and 71 with non-tuberculous lesions. The sensitivity of EBUS-GS with Xpert was significantly higher than BALF with Xpert (57.81% vs. 34.78%, P = 0.017). Use of EBUS-GS with Xpert and MGIT 960 culture further increased the sensitivity to 62.50% (95%CI 50.64-74.36) and increased the specificity to 100%. The AUC values of BALF with MGIT 960 culture was 0.663(95%CI 0.543-0.783) and BALF with Xpert was 0.674 (95%CI 0.556-0.792). The AUC values of EBUS-GS with MGIT 960 culture was 0.680 (95%CI 0.554-0.743), with pathological examination was 0.713 (95%CI 0.573-0.760), and with Xpert was 0.789 (95%CI 0.655-0.829). CONCLUSION: Use of EBUS-GS with Xpert had high sensitivity and specificity in the diagnosis of isolated pulmonary tuberculoma. This method has significant potential for use in clinical practice.

Rapid Identification of Nontuberculous Mycobacterium Species from Respiratory Specimens Using Nucleotide MALDI-TOF MS.

We performed a prospective study to evaluate the diagnostic accuracy of nucleotide matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) in identifying nontuberculous mycobacterium (NTM) from clinical respiratory samples. A total of 175 eligible patients were prospectively enrolled, including 108 patients diagnosed with NTM pulmonary disease (NTM-PD) and 67 control patients with other diseases. All specimens were subjected to acid-fast staining, liquid culture combined with MPT64 antigen detection, and a nucleotide MALDI-TOF MS assay. NTM cultures were also subjected to the MeltPro Myco assay for species identification. Altogether, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of nucleotide MALDI-TOF MS were 77.8% (95% CI: 68.6-85.0%), 92.5% (82.8-97.2%), 94.4% (86.8-97.9%), and 72.1% (61.2-81.0%), respectively; these results were not statistically different from the results of culture + MPT64 antigen testing (75.0% [65.6-82.6%], 95.5% [86.6-98.8%], 96.4% [89.2-99.1%], and 70.3% [59.7-79.2%], respectively). In the identification of NTM species, of the 84 nucleotide MALDI-TOF MS positive samples, 77 samples (91.7%) were identified at the species level. Using culture + MeltPro Myco assay as the reference standard, nucleotide MALDI-TOF MS correctly identified 77.8% (63/81) of NTM species. Our results demonstrated that the nucleotide MALDI-TOF MS assay was a rapid single-step method that provided the reliable detection of NTM and identification of NTM species. This new method had the same sensitivity and specificity as the culture + MPT64 antigen method, but was much more rapid.

A multifunctional integrated biomimetic spore nanoplatform for successively overcoming oral biological barriers.

The biological barriers have seriously restricted the efficacious responses of oral delivery system in diseases treatment. Utilizing a carrier based on the single construction means is hard to overcome these obstacles simultaneously because the complex gastrointestinal tract environment requires carrier to have different or even contradictory properties. Interestingly, spore capsid (SC) integrates many unique biological characteristics, such as high resistance, good stability etc. This fact offers a boundless source of inspiration for the construction of multi-functional oral nanoplatform based on SC without further modification. Herein, we develop a type of biomimetic spore nanoplatform (SC@DS NPs) to successively overcome oral biological barriers. Firstly, doxorubicin (DOX) and sorafenib (SOR) are self-assembled to form carrier-free nanoparticles (DS NPs). Subsequently, SC is effectively separated from probiotic spores and served as a functional vehicle for delivering DS NPs. As expect, SC@DS NPs can efficaciously pass through the rugged stomach environment after oral administration and further be transported to the intestine. Surprisingly, we find that SC@DS NPs exhibit a significant improvement in the aspects of mucus penetration and transepithelial transport, which is related to the protein species of SC. This study demonstrates that SC@DS NPs can efficiently overcome multiple biological barriers and improve the therapeutic effect.

Mupirocin enhances the biofilm formation of Staphylococcus epidermidis in an atlE-dependent manner.

The pathogenicity of Staphylococcus epidermidis is largely attributed to its exceptional ability to form biofilms. Here, we report that mupirocin, an antimicrobial agent widely used for staphylococcal decolonization and anti-infection, strongly stimulates the biofilm formation of S. epidermidis. Although the polysaccharide intercellular adhesin (PIA) production was unaffected, mupirocin significantly facilitated extracellular DNA (eDNA) release by accelerating autolysis, thereby positively triggering cell surface attachment and intercellular agglomeration during biofilm development. Mechanistically, mupirocin regulated the expression of genes encoding for the autolysin AtlE as well as the programmed cell death system CidA-LrgAB. Critically, through gene knockout, we found out that deletion of atlE, but not cidA or lrgA, abolished the enhancement of biofilm formation and eDNA release in response to mupirocin treatment, indicating that atlE is required for this effect. In Triton X-100 induced autolysis assay, mupirocin treated atlE mutant displayed a slower autolysis rate compared with the wild-type strain and complementary strain. Therefore, we concluded that subinhibitory concentrations of mupirocin enhance the biofilm formation of S. epidermidis in an atlE dependent manner. This induction effect could conceivably be responsible for some of the more unfavourable outcomes of infectious diseases.

Phenotypic and genomic analysis of the hypervirulent ST22 methicillin-resistant Staphylococcus aureus in China.

ST22 MRSA (methicillin-resistant Staphylococcus aureus) strains are only sporadically reported in China. Through the phylogenetic reconstruction of 30 ST22 strains from China and 480 ST22 strains from global sources, we found that the global ST22 strains can be divided into three clades (I, II, and III). The China ST22 strains were found primarily in clade II (IIb and IIc) and also in clade III, indicating that the China ST22-MRSA clones have different origins. The China subclade IIb strains (SCCmec Vb-t309) may evolve from the native ST22 MSSA clone, while the China IIc strains may have spread from other countries. Subclade IIc (SCCmecIVa-t309) strains exhibited particularly strong lethality and invasiveness in Galleria mellonella infection and mouse skin abscess models in comparison to USA300 and other dominant China HA-MRSA (ST5 and ST239) or CA-MRSA (ST59) strains. This study described the emergence of a highly virulent ST22 MRSA subclade and improved our insight into the molecular epidemiology of ST22 strains in China. IMPORTANCE ST22 is a successful hospital-associated MRSA lineage which first appeared in the United Kingdom as EMRSA-15. At present, ST22 MRSA clones are spreading rapidly around the world and even replaced other dominant clones in some regions. We placed the Chinese ST22 in the worldwide phylogeny of ST22, demonstrating a distinctive molecular epidemiology and to our knowledge, this is the first time that a novel clade of ST22 has been found in China. Among the 15 ST22 MRSA strains belonging to the novel clade, 14 ST22 SCCmecIVa strains from different regions carried both pvl and tst and displayed significantly higher in vitro and in vivo virulence in comparison to other clade/subclade ST22 strains as well as other common China HA-MRSA or CA-MRSA strains. The further spread of this subclade of strains could pose a serious threat to the health system in China and other regions.

Phylogenetic Analysis and Virulence Characteristics of Methicillin-Resistant Staphylococcus aureus ST45 in China: a Hyper-Virulent Clone Associated with Bloodstream Infections.

Methicillin-resistant Staphylococcus aureus (MRSA) sequence type 45 (ST45) was rarely found in China. This study was conducted to trace the transmission and evolution of emerging MRSA ST45 strains in mainland China and explore its virulence. A total of 27 ST45 isolates were included for whole-genome sequencing and genetic characteristic analysis. Epidemiological results showed that MRSA ST45 isolates were often obtained from blood, primarily originated in Guangzhou, and carried diverse virulence and drug resistance genes. Staphylococcal cassette chromosome mec type IV (SCCmec IV) dominated in MRSA ST45 (23/27, 85.2%). ST45-SCCmec V was located on a phylogenetic clade distinct from the SCCmec IV cluster. We selected two representative isolates, MR370 (ST45-SCCmec IV) and MR387 (ST45-SCCmec V), and performed hemolysin activity, a blood killing assay, a Galleria mellonella infection model, and a mouse bacteremia model, as well as real-time fluorescence quantitative PCR. MR370 was proved to have extreme virulence in the phenotypic assays and at the mRNA level compared with ST59, ST5, and USA300 MRSA strains. MR387 was comparable to USA300-LAC on the phenotype and was verified to have higher expression of scn, chp, sak, saeR, agrA, and RNAIII than USA300-LAC. The results emphasized the extraordinary performance of MR370 and the good potential of MR387 in virulence causing bloodstream infection. Meanwhile, we conclude that China MRSA ST45 showed two different clonotypes, which may be widespread in the future. The entire study is valuable as a timely reminder and reports virulence phenotypes of China MRSA ST45 for the first time. IMPORTANCE Methicillin-resistant Staphylococcus aureus ST45 is epidemic worldwide. This study contributed to the awareness of the Chinese hyper-virulent MRSA ST45 strains and served as a timely reminder of its wide dissemination of clonotypes. Further, we provide novel insights for prevention from the perspective of bloodstream infections. ST45-SCCmec V is a clonotype deserving special attention in China, and we performed genetic and phenotypic analyses for the first time on it.

Enhancement of Graphene Phonon Excitation by a Chemically Engineered Molecular Resonance.

The abstraction of pyrrolic hydrogen from a single phthalocyanine on graphene turns the molecule into a sensitive probe for graphene phonons. The inelastic electron transport measured with a scanning tunneling microscope across the molecular adsorbate and graphene becomes strongly enhanced for a graphene out-of-plane acoustic phonon mode. Supporting density functional and transport calculations elucidate the underlying physical mechanism. A molecular orbital resonance close to the Fermi energy controls the inelastic current while specific phonon modes of graphene are magnified due to their coupling to symmetry-equivalent vibrational quanta of the molecule.

Co-occurrence of OXA-232, RmtF-encoding plasmids, and pLVPK-like virulence plasmid contributed to the generation of ST15-KL112 hypervirulent multidrug-resistant Klebsiella pneumoniae.

The emergence of carbapenem-resistant Klebsiella pneumoniae (CRKP) strains and restricted therapeutic options pose a global threat to public health. Aminoglycosides are a wise choice, which can effectively reduce the mortality rate when combined with ß-lactam drugs. However, in this study, we identified a ST15-KL112 CRKP FK3006 which not only exhibited resistance to carbapenems, but also exhibited high level resistance to aminoglycosides. In addition to the multidrug resistant phenotype, FK3006 also owned typical pathogenic characteristic, including hypermucoviscosity and hypervirulence phenotypes. According to the whole-genome sequencing, one pLVPK-like virulence plasmid, and three key resistant plasmids (bla OXA-232, bla CTX-M-15, and rmtF) were observed in FK3006. Compared to other typical ST15 CRKP, the presence of pLVPK-like virulence plasmid (p3006-2) endowed the FK3006 with high virulence features. High siderophore production, more cell invasive and more resistant to serum killing was observed in FK3006. The Galleria mellonella infection model also further confirmed the hypervirulent phenotype of FK3006 in vivo. Moreover, according to the conjugation assay, p3006-2 virulence plasmid also could be induced transfer with the help of conjugative IncFIIK p3006-11 plasmid (bla CTX-M-15). In addition to the transmissible plasmid, several insertion sequences and transposons were found around bla CTX-M-15, and rmtF to generate the mobile antimicrobial resistance island (ARI), which also make a significant contribution to the dissemination of resistant determinants. Overall, we reported the uncommon co-existence of bla OXA-232, rmtF-encoding plasmids, and pLVPK-like virulence plasmid in ST15-KL112 K. pneumoniae. The dissemination threatens of these high-risk elements in K. pneumoniae indicated that future studies are necessary to evaluate the prevalence of such isolates.