Clinical characteristics and effects of inhaled corticosteroid in patients with post-COVID-19 chronic cough during the Omicron variant outbreak.

BACKGROUND: Chronic cough is a common symptom in patients post the coronavirus disease 2019 (COVID-19). In this study, we aimed to investigate the efficacy of inhaled corticosteroids (ICS) and the clinical characteristics of patients with post-COVID-19 chronic cough during the Omicron era. METHODS: An ambispective, longitudinal cohort study was conducted that included patients with post-COVID-19 who attended the respiratory clinic at our hospital between January 1, 2023, and March 31, 2023 with a complaint of persistent cough lasting more than 8 weeks. At 30 and 60 days after the first clinic visit for post-COVID-19 chronic cough, enrolled patients were prospectively followed up. We compared the changes in symptoms and pulmonary function between patients receiving ICS treatment (ICS group) and those not receiving ICS treatment (NICS group) at the two visits. RESULTS: A total of 104 patients with post-COVID-19 chronic cough were enrolled in this study (ICS group, n = 51; NICS group, n = 53). The most common symptoms accompanying post-COVID-19 chronic cough were sputum (58.7%, 61/104) and dyspnea (48.1%, 50/104). Seventy-one (82.6%, 71/86) patients had airway hyperresponsiveness, and 49 patients (47.1%, 49/104) were newly diagnosed with asthma. Most patients (95.2%, 99/104) exhibited improvement at 60 days after the first visit. The pulmonary function parameters of the patients in the ICS group were significantly improved compared to the baseline values (P < 0.05), and the improvement in the FEV1/FVC was significantly greater than that in the NICS group (P = 0.003) after 60 days. CONCLUSIONS: Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) may contribute to the pathogenesis of asthma, which could be the underlying cause of persistent cough post-COVID-19 infection. Post-COVID-19 chronic cough during the Omicron era was often accompanied by sputum, dyspnea, and airway hyperresponsiveness. ICS treatment did not have a significant impact on symptom management of post-COVID-19 chronic cough; however, it can improve impaired lung function in in these individuals.

Fixed-time neural network control of a robotic manipulator with input deadzone.

In this paper, a fixed-time control method is proposed for an uncertain robotic system with actuator saturation and constraints that occur a period of time after the system operation. A model-based control and a neural network-based learning approach are proposed under the framework of fixed-time convergence, respectively. We use neural networks to handle the uncertainty, and design an adaptive law driven by approximation errors to compensate the input deadzone. In addition, a new structure of stabilizing function combining with an error shifting function is introduced to demonstrate the robotic system stability and the boundedness of all error signals. It is proved that all the tracking errors converge into the compact sets near zero in fixed-time according to the Lyapunov stability theory. Simulations on a two-joint robot manipulator and experiments on a six-joint robot manipulator verified the effectiveness of the proposed fixed-time control algorithm.

Update on the natural orifice transluminal endoscopic surgery for gallbladder preserving gallstones therapy: A review.

Cholecystectomy remains the "gold standard" for the management of symptomatic gallstones. Minimally invasive laparoscopic cholecystectomy has been the treatment of choice for the past 3 decades. However, the technique of natural orifice transluminal endoscopic surgery cholecystolithotomy is evolving, with some experts advocating gallbladder stone removal without gallbladder excision in order to preserve gallbladder function and eliminate post-cholecystectomy syndromes, including complications of the surgical incision, bile duct injury, functional gastrointestinal, and psychological conditions, and possibly an increase in colon cancer. In addition, transluminal endoscopic cholecystolithotomy is an option for elderly patients who are not suitable candidates for open surgery and those who desire scar-free minimally invasive surgery with organ preservation. This article summarizes the established pure natural orifice transluminal endoscopic surgery gallbladder preserving gallstone removal techniques and highlights the pros and cons of different popular available endoscopic approaches to gallstone therapy and how flexible endoscopic surgery via the natural orifice is compared to the well-established cholecystectomy.

Immune-related gene signature associates with immune landscape and predicts prognosis accurately in patients with skin cutaneous melanoma.

Skin cutaneous melanoma (SKCM) is the skin cancer that causes the highest number of deaths worldwide. There is growing evidence that the tumour immune microenvironment is associated with cancer prognosis, however, there is little research on the role of immune status in melanoma prognosis. In this study, data on patients with Skin cutaneous melanoma were downloaded from the GEO, TCGA, and GTEx databases. Genes associated with the immune pathway were screened from published papers and lncRNAs associated with them were identified. We performed immune microenvironment and functional enrichment analyses. The analysis was followed by applying univariate/multivariate Cox regression algorithms to finally identify three lncRNAs associated with the immune pathway for the construction of prognostic prediction models (CXCL10, RXRG, and SCG2). This stepwise downscaling method, which finally screens out prognostic factors and key genes and then uses them to build a risk model, has excellent predictive power. According to analyses of the model's reliability, it was able to differentiate the prognostic value and continued existence of Skin cutaneous melanoma patient populations more effectively. This study is an analysis of the immune pathway that leads lncRNAs in Skin cutaneous melanoma in an effort to open up new treatment avenues for Skin cutaneous melanoma.

Identification of a Novel Acinetobacter baumannii Phage-Derived Depolymerase and Its Therapeutic Application in Mice.

The rapid expansion of Acinetobacter baumannii clinical isolates exhibiting resistance to most or all available antibiotics is a global concern. Current treatments for infections caused by this bacterium have become less effective, and the need to explore new alternative therapies is urgent. Depolymerases derived from phages are emerging as attractive anti-virulence agents. In this study, a previously isolated A. baumannii phage (designated as vB_AbaM_IME285) was characterized, and genomic study was carried out using various bioinformatics tools. A gene predicted as encoding for the depolymerase was cloned and expressed, and the depolymerase activity of the recombinant enzyme (Dp49) was identified both in vitro and in experimental mice. The results showed that phage IME285 formed translucent halos around the plaques when inoculated onto a lawn of the host bacteria, exibiting depolymerase activity against this strain. On the basis of complete genome sequencing and bioinformatics analysis, ORF49 was speculated to be a gene encoding for the putative capsule depolymerase. The expressed recombinant Dp49 displayed an effective depolymerase activity and had a spectrum of activity similar to its parental phage IME285, which was active against 25 out of 49 A. baumannii strains. It was found that Dp49 greatly improved the inhibitory effect of serum on bacterial growth in vitro, and the administration of this enzyme significantly increased the survival rates of A. baumannii-infected mice in the animal experiment. In conclusion, the phage-encoded depolymerase Dp49 might be a promising alternative means of controlling infections mediated by multidrug-resistant A. baumannii.

Tigecycline in the treatment of fulminant Mycoplasma pneumoniae pneumonia non-responsive to azithromycin and fluoroquinolone: A case report.

RATIONALE: Fulminant macrolide-resistant Mycoplasma pneumoniae pneumonia (MPP) has seldom been reported, and cases of MPP usually show rapid improvement after fluoroquinolones or tetracyclines addition. The purpose of this case report is to highlight the importance of proper selection of antibiotics for treatment of severe MPP and increase awareness concerning the emergence of fluoroquinolone-resistant MPP. PATIENT CONCERNS: A case of severe life-threatening pneumonia in a 26-year-old man with high fever and cough was non-responsive to azithromycin and fluoroquinolones. DIAGNOSES: The patient was diagnosed with MPP based on the test results of bronchoalveolar lavage using real-time quantitative PCR method. INTERVENTIONS: Tigecycline was given to the patient after azithromycin and fluoroquinolones failed. OUTCOMES: The patients fever subsided within the first day of tigecycline therapy. He showed rapid symptom resolution and improvement in lung infiltration after 4 days of tigecycline therapy. LESSONS: The case suggests that fulminant MPP should be timely treated with proper antibiotics, and the possible emergence of fluoroquinolone-resistant MPP should be of concern.

Development and Evaluation of a Loop-Mediated Isothermal Amplification Assay for Rapid and Specific Identification of Carbapenem-Resistant Acinetobacter baumannii Strains Harboring blaOXA-23, and the Epidemiological Survey of Clinical Isolates.

Acinetobacter baumannii is an important nosocomial pathogen in hospital-acquired infections, and carbapenem resistance has been increasingly observed worldwide. Oxacillinase production by blaOXA-23 is a predominant and prevalent carbapenem resistance mechanism of A. baumannii, especially in China. Rapid and specific detection of blaOXA-23 may offer valuable insight for administration of directed antimicrobial therapy. In this study, we aimed to develop a loop-mediated isothermal amplification (LAMP)-based method for identifying carbapenem-resistant A. baumannii (CRAB) harboring the blaOXA-23 gene. High-specificity primers for screening blaOXA-23 were designed and synthesized, and the LAMP reactions were performed. Clinical A. baumannii strains isolated from the Former 307th Hospital of People's Liberation Army were used to determine the sensitivity and specificity of this method compared with those of phenotypic antimicrobial susceptibility testing and the traditional PCR method. Multilocus sequence typing (MLST) was performed to investigate the epidemiology of the A. baumannii bacterial population. Compared with antimicrobial susceptibility testing, the sensitivity and specificity of LAMP in detecting blaOXA-23 were 88.4% and 97.7%, respectively. However, the LAMP method is much simpler and less time-consuming (within 60 minutes) than conventional PCR and phenotypic susceptibility testing. The 113 isolates could be clustered into 30 sequence types, and most strains (83/113) belonged to clonal complex (CC) 92, which is also the dominant CC in China. The LAMP-based method detected blaOXA-23 in a simpler manner and could provide rapid results for identifying CRAB. Consequently, blaOXA-23 may serve as a surrogate marker for the presence of CRAB in patients with serious infections in clinical practice.

Efficacy of pulmonary transplantation of engineered macrophages secreting IL-4 on acute lung injury in C57BL/6J mice.

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are major causes of respiratory failure, but currently, no effective pharmacotherapy exists for these disorders. Alveolar macrophages play a critical role in both the acute/initial phase and chronic/resolving phase of ALI, rendering them a potential therapeutic target. Interleukin-4 (IL-4), a Th2 cytokine, not only directly inhibits the secretion of pro-inflammatory factors from macrophages but also drives macrophages to the anti-inflammatory and tissue remodeling M2 type. However, the short half-life of IL-4 in vivo hampers its effect on disease treatment. In this study, macrophages secreting IL-4 (M-IL-4) were established and used to treat ALI through pulmonary macrophage transplantation (PMT). The results showed that highly sustained levels of IL-4 and M2 macrophage markers were detected in mice lungs following pulmonary M-IL-4 transplantation. Furthermore, PMT improved the therapeutic effect by reducing lung inflammation, alleviating tissue injury, reducing alveolar macrophages necrotic cell death, and decreasing mortality in mice with ALI. These results suggest an efficient macrophage-based protein drug delivery strategy, and for the first time, prove the feasibility and efficacy of PMT in ALI treatment.

LncRNA analysis of lung tissues after hUC-MSCs and FTY720 treatment of lipopolysaccharide-induced acute lung injury in mouse models.

Acute lung injury (ALI), a persistent lung inflammatory response syndrome, may evolve into acute respiratory distress syndrome (ARDS). Characterized by rapid onset, critical features, and a complex etiology, ALI remains a challenging critical respiratory disease. Recently, mesenchymal stem cells (MSCs) have provided a new solution for the treatment of ALI. We built a lipopolysaccharide (LPS)-induced ALI model in mice. After treatment with human umbilical cord mesenchymal stem cells (hUC-MSCs), FTY720, or a combination of hUC-MSCs and FTY207, the lung inflammatory response was apparently attenuated. To understand the mechanism underlying MSCs treatment of ALI at the genetic level, significant differentially expressed long non-coding RNAs (lncRNAs) between the treatment and model groups were analyzed using microarray technology. Moreover, genetic gene prediction, gene ontology (GO) analysis, pathway analysis, and transcription factor (TF) prediction were carried out. The results showed that a total of 66 lncRNAs were differentially expressed in all three treatment groups, including 8 up-regulated and 58 down-regulated lncRNAs. LncRNA A_30_P01029806 and A_30_P01029194, which were down-regulated, were involved in the signaling pathways closely related to ALI. Through further TF analysis, we identified several significant TFs which lay a foundation for revealing the mechanism underlying lncRNAs treatment of ALI. LncRNA A_30_P01029806 and A_30_P01029194 may serve as candidate biomarkers in the diagnosis and treatment of ALI.

Protective and therapeutic application of the depolymerase derived from a novel KN1 genotype of Klebsiella pneumoniae bacteriophage in mice.

Klebsiella pneumoniae is one of the major Gram-negative bacterial pathogens causing hospital-acquired multidrug-resistant infections, and the antimicrobial treatment options are scarce. The lack of available antimicrobials has prompted the development of alternative strategies for the treatment of these infections. In this study, a K. pneumoniae bacteriophage (vB_KpnP_IME321) targeting a KN1 capsular type strain, Kp409, was isolated, characterized and sequenced. This bacteriophage has a latent period of 20 min and a burst size of approximately 410 pfu/cell. It contained 49 predicted open reading frames, of which ORF42 was identified as encoding the putative capsule depolymerase. The enzyme expressed and purified in the Escherichia coli BL21 system, namely Dp42, could depolymerize the capsular polysaccharide of Kp409 and form translucent halos on the plates. The phage-encoded depolymerase could increase the inhibitory effect of serum on the growth of bacteria in vitro. Pre-treated with Dp42 rescued 100% of mice following lethal Kp409 challenge, and administration of this enzyme after infection significantly increased survival rates of infected mice in the animal experiment. In conclusion, the phage-encoded depolymerase Dp42 represents a potential alternative strategy for controlling infections mediated by K. pneumoniae expressing the KN1 capsular polysaccharide.

Identification and characterization of capsule depolymerase Dpo48 from Acinetobacter baumannii phage IME200.

BACKGROUND: The emergence of multidrug- or extensively drug-resistant Acinetobacter baumannii has made it difficult to treat and control infections caused by this bacterium. It is urgently necessary to search for alternatives to conventional antibiotics for control of severe A. baumannii infections. In recent years, bacteriophages and their derivatives, such as depolymerases, showed great potential as antibacterial or antivirulence agents against bacterial infections. Nonetheless, unlike broad-spectrum bactericidal antibiotics, phage-encoded depolymerase targets only a limited number of bacterial strains. Therefore, identification of novel depolymerases and evaluation of their ability to control A. baumannii infections is important. METHODS: A bacteriophage was isolated from hospital sewage using an extensively drug-resistant A. baumannii strain as the host bacterium, and the phage's plaque morphology and genomic composition were studied. A polysaccharide depolymerase (Dpo48) was expressed and identified, and the effects of pH and temperature on its activity were determined. Besides, a serum killing assay was conducted, and amino acid sequences homologous to those of putative polysaccharide depolymerases were compared. RESULTS: Phage IME200 yielded clear plaques surrounded by enlarged halos, with polysaccharide depolymerase activity against the host bacterium. A tail fiber protein with a Pectate_lyase_3 domain was identified as Dpo48 and characterized . Dpo48 was found to degrade the capsule polysaccharide of the bacterial surface, as revealed by Alcian blue staining. Dpo48 manifested stable activity over a broad range of pH (5.0-9.0) and temperatures (20-70 °C). Results from in vitro serum killing assays indicated that 50% serum was sufficient to cause a five log reduction of overnight enzyme-treated bacteria, with serum complement playing an important role in these killing assays. Moreover, Dpo48 had a spectrum of activity exactly the same as its parental phage IME200, which was active against 10 out of 41 A. baumannii strains. Amino acid sequence alignment showed that the putative tail fiber proteins had a relatively short, highly conserved domain in their N-terminal sequences, but their amino acid sequences containing pectate lyase domains, found in the C-terminal regions, were highly diverse. CONCLUSIONS: Phage-encoded capsule depolymerases may become promising antivirulence agents for preventing and controlling A. baumannii infections.

Transcriptomic analysis of lung tissues after hUC-MSCs and FTY720 treatment of lipopolysaccharide-induced acute lung injury in mouse models.

Acute lung injury and acute respiratory distress syndrome (ALI/ARDS) refer to acute and progressive hypoxic respiratory failure caused by non-cardiogenic factors, which is a common condition occurring in critically ill patients with widespread pulmonary inflammation. Use of a single medication or target cannot treat ALI/ARDS. Mesenchymal stem cells (MSCs) and FTY720, as an analogue of sphingosine-1-phosphate (S1P), can mitigate lipopolysaccharide (LPS)-induced inflammatory lung injury. In this investigation, the clinical efficacy of MSCs alone, FTY720 alone, and a MSC and FTY720 combination in the treatment of LPS-induced lung injury was evaluated in mouse models. The experimental results demonstrated that both MSCs and FTY720 alleviate lung injuries in mice. The combined application of MSCs and FTY720 yielded higher clinical efficacy in mitigating lung injuries compared with use of MSCs or FTY720 alone. Transcriptomic analysis was performed using an Agilent gene expression chip. By analyzing the differences in gene expression of lung tissues between treated and non-treated ALI/ARDS mice, Gene Ontology and Pathway terms related to ALI/ARDS treatment were identified. Moreover, the target genes which might play a pivotal role in the treatment of ALI/ARDS were also detected, thus providing a theoretical basis for multi-target or multi-drug combined treatment of ALI/ARDS and lay a solid foundation for clinical treatment of ALI/ARDS.

Combination therapy of human umbilical cord mesenchymal stem cells and FTY720 attenuates acute lung injury induced by lipopolysaccharide in a murine model.

ALI/ARDS remain the main reason of morbidity and mortality in the critically ill. Studies have indicated that human umbilical cord mesenchymal stem cells (hUC-MSCs) can be useful in the treatment of ALI/ARDS. Sphingosine-1-phosphate (S1P) and its analog FTY720 significantly reduce lipopolysaccharide (LPS)-induced lung edema and inflammatory lung injury. This study aimed to assess the therapeutic effects of hUC-MSCs combined with FTY720 in an LPS-induced murine model of ALI. Eight-week-old female C57BL/6 mice were divided into a normal control group, an LPS group, an hUC-MSC group, an FTY720 group, and an hUC-MSCs+FTY720 group randomly. At 24 hours post injury, mice were administrated hUC-MSCs via the tail vein and/or intraperitoneally injected with FTY720. We assessed histopathology and histologic scores, lung wet/dry weight ratio, micro-CT scans, and total protein in the bronchoalveolar lavage fluid (BALF), as well as cytokines in the BALF at 48 h post injury. All treatment groups showed higher survival rates and attenuated lung injuries. The hUC-MSCs+FTY720 group yielded better results than hUC-MSCs or FTY720 alone. While the underlying mechanism requires further study, we anticipate that combination therapy of hUC-MSCs and FTY720 could be an effective strategy for ALI.

Isolation and Whole-genome Sequence Analysis of the Imipenem Heteroresistant Acinetobacter baumannii Clinical Isolate HRAB-85.

OBJECTIVES: Heteroresistance is a phenomenon in which there are various responses to antibiotics from bacterial cells within the same population. Here, we isolated and characterised an imipenem heteroresistant Acinetobacter baumannii strain (HRAB-85). METHODS: The genome of strain HRAB-85 was completely sequenced and analysed to understand its antibiotic resistance mechanisms. Population analysis and multilocus sequence typing were performed. RESULTS: Subpopulations grew in the presence of imipenem at concentrations of up to 64µg/mL, and the strain was found to belong to ST208. The total length of strain HRAB-85 was 4,098,585bp with a GC content of 39.98%. The genome harboured at least four insertion sequences: the common ISAba1, ISAba22, ISAba24, and newly reported ISAba26. Additionally, 19 antibiotic-resistance genes against eight classes of antimicrobial agents were found, and 11 genomic islands (GIs) were identified. Among them, GI3, GI10, and GI11 contained many ISs and antibiotic-resistance determinants. CONCLUSIONS: The existence of imipenem heteroresistant phenotypes in A. baumannii was substantiated in this hospital, and imipenem pressure, which could induce imipenem-heteroresistant subpopulations, may select for highly resistant strains. The complete genome sequencing and bioinformatics analysis of HRAB-85 could improve our understanding of the epidemiology and resistance mechanisms of carbapenem-heteroresistant A. baumannii.

Regulation of S1P receptors and sphingosine kinases expression in acute pulmonary endothelial cell injury.

BACKGROUND: Acute lung injury and acute respiratory distress syndrome (ALI/ARDS) is a severe clinical syndrome with mortality rate as high as 30-40%. There is no treatment yet to improve pulmonary endothelial barrier function in patients with severe pulmonary edema. Developing therapies to protect endothelial barrier integrity and stabilizing gas exchange is getting more and more attention. Sphingosine-1-phosphate (S1P) is able to enhance the resistance of endothelial cell barrier. S1P at physiological concentrations plays an important role in maintaining endothelial barrier function. Proliferation, regeneration and anti-inflammatory activity that mesenchymal stem cells (MSCs) exhibit make it possible to regulate the homeostatic control of S1P. METHODS: By building a pulmonary endothelial cell model of acute injury, we investigated the regulation of S1P receptors and sphingosine kinases expression by MSCs during the treatment of acute lung injury using RT-PCR, and investigated the HPAECs Micro-electronics impedance using Real Time Cellular Analysis. RESULTS: It was found that the down-regulation of TNF-α expression was more significant when MSC was used in combination with S1P. The combination effection mainly worked on S1PR2, S1PR3 and SphK2. The results show that when MSCs were used in combination with S1P, the selectivity of S1P receptors was increased and the homeostatic control of S1P concentration was improved through regulation of expression of S1P metabolic enzymes. DISCUSSIONS: The study found that, as a potential treatment, MSCs could work on multiple S1P related genes simultaneously. When it was used in combination with S1P, the expression regulation result of related genes was not simply the superposition of each other, but more significant outcome was obtained. This study establishes the experimental basis for further exploring the efficacy of improving endothelial barrier function in acute lung injury, using MSCs in combination with S1P and their possible synergistic mechanism.

Clinical and Virological Characteristics of Ebola Virus Disease Patients Treated With Favipiravir (T-705)-Sierra Leone, 2014.

BACKGROUND: During 2014-2015, an outbreak of Ebola virus disease (EVD) swept across parts of West Africa. No approved antiviral drugs are available for Ebola treatment currently. METHODS: A retrospective clinical case series was performed for EVD patients in Sierra Leone-China Friendship Hospital. Patients with confirmed EVD were sequentially enrolled and treated with either World Health Organization (WHO)-recommended supportive therapy (control group) from 10 to 30 October, or treated with WHO-recommended therapy plus favipiravir (T-705) from 1 to 10 November 2014. Survival and virological characteristics were observed for 85 patients in the control group and 39 in the T-705 treatment group. RESULTS: The overall survival rate in the T-705 treatment group was higher than that of the control group (56.4% [22/39] vs 35.3% [30/85]; P = .027). Among the 35 patients who finished all designed endpoint observations, the survival rate in the T-705 treatment group (64.8% [11/17]) was higher than that of the control group (27.8% [5/18]). Furthermore, the average survival time of the treatment group (46.9 ± 5.6 days) was longer than that of the control group (28.9 ± 4.7 days). Most symptoms of patients in the treatment group improved significantly. Additionally, 52.9% of patients who received T-705 had a >100-fold viral load reduction, compared with only 16.7% of patients in the control group. CONCLUSIONS: Treatment of EVD with T-705 was associated with prolonged survival and markedly reduced viral load, which makes a compelling case for further randomized controlled trials of T-705 for treating EVD.

Potential of a lytic bacteriophage to disrupt Acinetobacter baumannii biofilms in vitro.

AIM: The ability of Acinetobacter baumannii to form biofilms and develop antibiotic resistance makes it difficult to control infections caused by this bacterium. In this study, we explored the potential of a lytic bacteriophage to disrupt A. baumannii biofilms. MATERIALS & METHODS: The potential of the lytic bacteriophage to disrupt A. baumannii biofilms was assessed by performing electron microscopy, live/dead bacterial staining, crystal violet staining and by determining adenosine triphosphate release. RESULTS: The bacteriophage inhibited the formation of and disrupted preformed A. baumannii biofilms. Results of disinfection assay showed that the lytic bacteriophage lysed A. baumannii cells suspended in blood or grown on metal surfaces. CONCLUSION: These results suggest the potential of the lytic bacteriophage to disrupt A. baumannii biofilms.

Intranasal treatment with bacteriophage rescues mice from Acinetobacter baumannii-mediated pneumonia.

AIM: With the emergence of drug-resistant bacteria, finding alternative agents to treat antibiotic-resistant bacterial infections is imperative. MATERIALS & METHODS: A mouse pneumonia model was developed by combining cyclophosphamide pretreatment and Acinetobacter baumannii challenge, and a lytic bacteriophage was evaluated for its therapeutic efficacy in this model by examining the survival rate, bacterial load in the lung and lung pathology. RESULTS: Intranasal instillation with bacteriophage rescued 100% of mice following lethal challenge with A. baumannii. Phage treatment reduced bacterial load in the lung. Microcomputed tomography indicated a reduction in lung inflammation in mice given phage. CONCLUSION: This research demonstrates that intranasal application of bacteriophage is viable, and could provide complete protection from pneumonia caused by A. baumannii.

[To evaluate the auxiliary diagnostic value of Japanese respiratory society scoring system for the rapid diagnosis of Mycoplasma pneumoniae pneumonia in inpatients with community acquired pneumonia].

OBJECTIVE: To evaluate the auxiliary diagnostic value of Japanese respiratory society (JRS) scoring system for the rapid diagnosis of Mycoplasma pneumoniae pneumonia (MP) in inpatients with community acquired pneumonia (CAP). METHODS: The clinical data of inpatients with CAP between January 2013 and Novermber 2013 were retrospectively analyzed. The gold standard for identification of MP infection was determined by both positive culture and real time polymerase chain reaction (PCR) methods. Blood and sputum culture were used to detect other bacteria and fungi, and real time PCR to detect Chlamydia and Legionella pneumonia and the common respiratory viruses. Diagnostic test results consistency inspection was performed by Kappa test and continuous variable analysis was performed using t test. RESULTS: Data from 139 CAP inpatients were analyzed. An aetiological diagnosis was made for 61 patients (43.9%). Thirty-five cases (25.2%) were diagnosed as MP infection by the gold standard, while 72 cases (52.0%) by the JRS scoring system. The sensitivity of JRS scoring system for the diagnosis of MP infection was 85.7% (30/35), specificity 59.6% (62/104), positive predictive value 41.7% (30/72)and negative predictive value 92.5% (62/67). According to age, for the patients younger than 40 years old, the sensitivity of JRS routine scoring system for the diagnosis of MP infection was 24/24, specificity was 4/29, positive predictive value 24/49 and negative predictive value was 4/4. CONCLUSIONS: The JRS scoring system provides an auxiliary value for the identification of MP pneumonia. It has a high sensitivity and a strong negative predictive value. For patients younger than 40 yrs with low grades of JRS swring system. MP infection can be almost excluded from.

Rapid detection of Acinetobacter baumannii and molecular epidemiology of carbapenem-resistant A. baumannii in two comprehensive hospitals of Beijing, China.

Acinetobacter baumannii is an important opportunistic pathogen associated with a variety of nosocomial infections. A rapid and sensitive molecular detection in clinical isolates is quite needed for the appropriate therapy and outbreak control of A. baumannii. Group 2 carbapenems have been considered the agents of choice for the treatment of multiple drug-resistant A. baumannii. But the prevalence of carbapenem-resistant A. baumannii (CRAB) has been steadily increasing in recent years. Here, we developed a loop-mediated isothermal amplification (LAMP) assay for the rapid detection of A. baumannii in clinical samples by using high-specificity primers of the bla OXA-51 gene. Then we investigated the OXA-carbapenemases molecular epidemiology of A. baumannii isolates in two comprehensive hospitals in Beijing. The results showed that the LAMP assay could detect target DNA within 60 min at 65°C. The detection limit was 50 pg/µl, which was about 10-fold greater than that of PCR. Furthermore, this method could distinguish A. baumannii from the homologous A. nosocomialis and A. pittii. A total of 228 positive isolates were identified by this LAMP-based method for A. baumannii from 335 intensive care unit patients with clinically suspected multi-resistant infections in two hospitals in Beijing. The rates of CRAB are on the rise and are slowly becoming a routine phenotype for A. baumannii. Among the CRABs, 92.3% harbored both the bla OXA-23 and bla OXA-51 genes. Thirty-three pulsotypes were identified by pulsed-field gel electrophoresis, and the majority belonged to clone C. In conclusion, the LAMP method developed for detecting A. baumannii was faster and simpler than conventional PCR and has great potential for both point-of-care testing and basic research. We further demonstrated a high distribution of class D carbapenemase-encoding genes, mainly OXA-23, which presents an emerging threat in hospitals in China.