Characteristics of Helicobacter pylori Heteroresistance in Gastric Biopsies and Its Clinical Relevance.

BACKGROUND: Antimicrobial susceptibility testing (AST) plays a vital role in anti-Helicobacter pylori treatment, but the traditional AST method has difficulty detecting heteroresistance, which may cause an increased prevalence of resistant strains and eradication failure. AIMS: To investigate the characteristics of heteroresistance in H. pylori in gastric biopsies and investigate its clinical relevance. METHOD: A total of 704 gastric biopsies were selected for 23S rRNA and gyrA gene sequencing, 470 H. pylori isolates from these biopsies were selected for AST, and the clinical characteristics of the patients were reviewed. RESULT: For the 699 biopsies that were positive for 23S rRNA gene, 98 (14.0%) showed a heteroresistance genotype, and a wild type (WT) combined with A2143G (86.7%) genotype was found in most samples. For the 694 biopsies that were positive for gyrA gene, 99 (14.3%) showed a heteroresistance genotype, and a WT combined with 87K (26.3%) or WT combined with 91N (23.2%) genotype was predominant. According to the E-test results, the resistance rates of heteroresistance genotype samples for clarithromycin and levofloxacin were 36.2% and 68.1%, respectively. When dividing the heteroresistance samples into different groups according to the sequencing profile peaks of the mutation position, the resistance rates were higher along with mutation peaks at the mutation position. In addition, patients infected with mutated or heteroresistant strains showed lower peptic ulcer detection rates than those infected with the WT strain (p < 0.05). CONCLUSION: Heteroresistance genotypes for clarithromycin and levofloxacin were not rare in H. pylori. Most cases with a heteroresistance genotype showed a susceptible phenotype for clarithromycin and a resistance phenotype for levofloxacin. Patients infected with heteroresistance genotype strains showed a lower peptic ulcer detection rate than those infected with the WT strain.

Reduction of Human DNA Contamination in Clinical Cerebrospinal Fluid Specimens Improves the Sensitivity of Metagenomic Next-Generation Sequencing.

Metagenomics next-generation sequencing (mNGS) is increasingly available for the detection of obscure infectious diseases of the central nervous system. However, human DNA contamination from elevated white cells, one of the characteristic cerebrospinal fluid (CSF) features in meningitis patients, greatly reduces the sensitivity of mNGS in the pathogen detection. Currently, effective approaches to selectively reduce host DNA contamination from clinical CSF samples are still lacking. In this study, a total of 20 meningitis patients were enrolled, including 10 definitively diagnosed tuberculous meningitis (TBM) and 10 definite cryptococcal meningitis (CM) cases. To evaluate the effect of reduced human DNA in the sensitivity of mNGS detection, three specimen-processing protocols were performed: (i) To remove human DNA, saponin, a nonionic surfactant, was used to selectively lyse white cells in CSF followed by DNase treatment prior to the extraction of DNA; (ii) to reduce host DNA, CSF was centrifuged to remove human cells, and the supernatant was collected for DNA extraction; and (iii) DNA extraction from the unprocessed specimens was set as the control. We found that saponin processing significantly elevated the NGS unique reads for Cryptococcus (P < 0.01) compared with the control but had no effects for Mycobacterium tuberculosis (P > 0.05). However, detection of centrifuged supernatants improved the NGS unique reads for both TBM and CM compared with controls (P < 0.01). Our results demonstrate that the use of mNGS of centrifuged supernatants from clinical CSF samples in patients with TBM and CM is a simple and effective method to improve the sensitivity of pathogen detection.

Fine particulate matter (PM2.5): The culprit for chronic lung diseases in China.

Air pollution is a world public health problem. Particulate matter (PM), a mix of solid and liquid particles in the air, becomes an increasing concern in the social and economic development of China. For decades, epidemiological studies have confirmed the association between fine particle pollutants and respiratory diseases. It has been reported in different populations that increased Fine particulate matter (PM2.5) concentrations cause elevated susceptibility to respiratory diseases, including acute respiratory distress, asthma, chronic obstructive pulmonary disease, and lung cancer. This review will discuss the pathophysiology of PM2.5 in respiratory diseases, which are helpful for the prevention of air pollution and treatment of respiratory tract inflammatory diseases.

Inhibitive Effects of FGF2/FGFR1 Pathway on Astrocyte-Mediated Inflammation in vivo and in vitro After Infrasound Exposure.

Infrasound, a kind of ambient noise, can cause severe disorders to various human organs, specially to central nervous system (CNS). Our previous studies have shown that infrasound-induced CNS injury was closely related with astrocytes activation and astrocytes-mediated neuroinflammation, but the underlying molecular mechanisms are still largely unclear. FGF2/FGFR1 (Fibroblast growth factor 2/Fibroblast growth factor receptor 1) pathway was reported to play an important role in anti-inflammation in CNS disorders. To further study the possible roles of FGF2/FGFR1 pathway in infrasound-induced CNS injury, here we exposed Sprague-Dawley rats or cultured astrocytes to 16 Hz, 150 dB infrasound, and explored the effects of FGF2 on infrasound-induced astrocytes activation and neuroinflammation. Western blotting, immunofluorescence and liquid chip method were used in this experiment. Our results showed that after 3- or 7-day exposure (2 h/day) of rats as well as 2 h exposure of cultured astrocytes to 16 Hz, 150 dB infrasound, astrocyte-expressed FGFR1 was downregulated in vivo and in vitro. FGF2 pretreatment not only inhibited infrasound-induced astrocyte activation in rat hippocampal CA1 region, but also reduced the levels of pro-inflammatory cytokines, such as TNF-α, IL-1ß, IL-18, IL-6, and IFN-γ in vitro and in vivo. However, FGF2 significantly upregulated the expression of FGFR1. Furthermore, we showed that FGF2 could attenuate IκBα phosphorylation, NF-κB p65 translocation, pro-inflammatory cytokines levels, and neuronal loss in the CA1 region induced by infrasound. On the contrary, PD173074, a special antagonist of FGFR1, could reverse the effects above in vitro and in vivo. Taken together, our findings showed that FGF2/FGFR1 pathway may exert inhibitive effects on astrocyte-mediated neuroinflammation in vitro and in vivo after infrasound exposure.

Air pollutants and early origins of respiratory diseases.

Air pollution is a global health threat and causes millions of human deaths annually. The late onset of respiratory diseases in children and adults due to prenatal or perinatal exposure to air pollutants is emerging as a critical concern in human health. Pregnancy and fetal development stages are highly susceptible to environmental exposure and tend to develop a long-term impact in later life. In this review, we briefly glance at the direct impact of outdoor and indoor air pollutants on lung diseases and pregnancy disorders. We further focus on lung complications in later life with early exposure to air pollutants. Epidemiological evidence is provided to show the association of prenatal or perinatal exposure to air pollutants with various adverse birth outcomes, such as preterm birth, lower birth weight, and lung developmental defects, which further associate with respiratory diseases and reduced lung function in children and adults. Mechanistic evidence is also discussed to support that air pollutants impact various cellular and molecular targets at early life, which link to the pathogenesis and altered immune responses related to abnormal respiratory functions and lung diseases in later life.

Effects of particulate matter on allergic respiratory diseases.

The health impact of airborne particulate matter (PM) has long been a concern to clinicians, biologists, and the general public. With many epidemiological studies confirming the association of PM with allergic respiratory diseases, an increasing number of follow-up empirical studies are being conducted to investigate the mechanisms underlying the toxic effects of PM on asthma and allergic rhinitis. In this review, we have briefly introduced the characteristics of PM and discussed its effects on public health. Subsequently, we have focused on recent studies to elucidate the association between PM and the allergic symptoms of human respiratory diseases. Specifically, we have discussed the mechanism of action of PM in allergic respiratory diseases according to different subtypes: coarse PM (PM2.5-10), fine PM (PM2.5), and ultrafine PM.

Targeting Neutrophils in Severe Asthma via Siglec-9.

Severe asthma comprises only 5% of patients with asthma, but the burden it brings to the social health system accounts for more than half of all asthmatics. Clinical evidence shows that severe asthma is often linked to the recruitment and activation of neutrophils in the airways. However, the underlying molecular and immunological mechanisms of neutrophilia in severe asthma are not clear and currently available drugs exert only limited effects on neutrophilic inflammation. Great efforts are underway to address the mystery of neutrophilic inflammation in chronic respiratory disorders. Sialic acid-binding immunoglobulin-like lectins (Siglecs) are members of the immunoglobulin gene family. Of note, Siglec-9 is uniquely expressed by human neutrophils and monocytes, as well as a minor population of natural killer cells. Engaging this structure with antibodies or glycan ligands results in programmed cell death in human neutrophils. Intriguingly, the administration of Siglec-E antibody abolished the recruitment of neutrophils in mouse models of neutrophilic pulmonary inflammation in vivo. Given that neutrophils are probably a major culprit in the generation and perpetuation of inflammation, targeting Siglec-9 could be beneficial for the treatment of severe asthma, chronic obstructive pulmonary disease, and related pulmonary disorders characteristic of neutrophilia.

In vivo near-infrared fluorescence imaging of amyloid-ß plaques with a dicyanoisophorone-based probe.

A dicyanoisophorone-based probe with two-photon absorption and NIR emission was developed for the in vivo fluorescence imaging of amyloid-ß plaques, which exhibited high selectivity toward Aß aggregates over other intracellular proteins. The detection limit was calculated to be as low as 109 nM. In vivo imaging studies indicated that the probe could penetrate the blood-brain barrier and label Aß plaques in the living transgenic mice, and its specific binding to cerebral Aß plaques was further confirmed by one- and two-photon ex vivo fluorescence imaging. All these results featured its promising application prospects for amyloid-ß sensing in basic research and biomedical research.

Sub-optimal Specificity of Modified Ziehl-Neelsen Staining for Quick Identification of Tuberculous Meningitis.

Background: Microbiological confirmation of tuberculous meningitis (TBM) remains problematic. We assessed the diagnostic performance of a modified Ziehl-Neelsen (MZN) staining method that showed promise in earlier studies. Methods: Patients evaluated for TBM in Shaanxi province, China, were prospectively enrolled from May, 2011 to April, 2013. Cerebrospinal fluid (CSF) specimens were evaluated using the Xpert MTB/RIF® assay, MZN staining, and standard biochemical and microbiological tests, together with detailed clinical and radiological assessment. Results: Among 316 patients included in the study, 38 had definite TBM, 66 probable TBM, 163 possible TBM and 49 "no TBM," using consensus uniform research case definition criteria. Comparing "definite or probable TBM" to "no TBM" MZN staining had higher sensitivity than Xpert MTB/RIF® (88.5 vs. 36.5%), but greatly reduced specificity (71.4 vs. 100.0%); 14/49 (28.6%) cases with "no TBM" tested positive on MZN. Mycobacterium tuberculosis culture was performed in 104/179 (58.1%) of MZN positive samples; 12.5% (13/104) were positive. Using Xpert MTB/RIF® as the reference standard, MZN had a sensitivity of 92.1% (95% CI 79.2-97.3) and specificity of 71.4% (95% CI 57.6-82.2). Conclusion: Xpert MTB/RIF® offered a rapid and specific TBM diagnosis, but sensitivity was poor. MZN was mainly hampered by false positives. Strategies to enhance the sensitivity of Xpert MTB/RIF® or improve the diagnostic accuracy of MZN should be explored.

MAPK/JNK signalling: a potential autophagy regulation pathway.

Autophagy refers to a lysosomal degradative pathway or a process of self-cannibalization. This pathway maintains nutrients levels for vital cellular functions during periods of starvation and it provides cells with survival advantages under various stress situations. However, the mechanisms responsible for the induction and regulation of autophagy are poorly understood. The c-Jun NH2-terminal kinase (JNK) signal transduction pathway functions to induce defence mechanisms that protect organisms against acute oxidative and xenobiotic insults. This pathway has also been repeatedly linked to the molecular events involved in autophagy regulation. The present review will focus on recent advances in understanding of the relationship between mitogen-activated protein kinase (MAPK)/JNK signalling and autophagic cell death.

Effect of Golgi phosphoprotein 2 (GOLPH2/GP73) on autophagy in human hepatocellular carcinoma HepG2 cells.

This study aims to investigate the effect of Golgi Protein 73 (GP73) on autophagy in human hepatoma line cells HepG2. We investigated the functional effects of GP73 on autophagy in hepatoma cell line HepG2 using immunofluoscence staining, Western blotting and real-time PCR. Our data showed that specific small interference RNA (siRNA) notably induced formation of autophagic vacuoles. In addition, upregulation of GP73 significantly inhibited formation of starvation-induced LC3-positive structures. We provide the first experimental evidence to show that GP73 may play an important role in the inhibitory regulation of autophagy. Therefore, our data suggest a new molecular mechanism for GP73-related hepatoma progression.

Development and characterization of a novel fusion protein of a mutated granulocyte colony-stimulating factor and human serum albumin in Pichia pastoris.

The purpose of the present work was to develop a novel, long-acting and potent human serum albumin/granulocyte colony stimulating factor (HSA/G-CSF) therapeutic fusion protein. The novel fusion protein, called HMG, was constructed by genetically fusing mutated human derived G-CSF (mG-CSF) to the C-terminal of HSA and then prepared in Pichia pastoris. The molecular mass of HMG was about 85 kDa and the isoelectric point was 5.3. Circular dichroism spectroscopy suggested that mG-CSF retained nearly all of its native secondary structure, regardless of fusion. The binding capabilities of mG-CSF moiety to G-CSF receptor and HSA moiety to warfarin showed very little change after fusing. The bioactivity of HMG (11.0×10(6) IU/mg) was more than twice that of rHSA/G-CSF (4.6×10(6) IU/mg). A mutation was made at the 718th amino acid of HMG, substituting Ala for Thr, to investigate the glycosylation of HMG expressed in P. pastoris. Data indicated that HMG was modified at Thr718, speculatively with the addition of a mannose chain. In conclusion, a novel HSA/G-CSF fusion protein was successfully constructed based on a mutated G-CSF. This protein showed more potent bioactivity than rHSA/G-CSF and thus may be a suitable long-acting G-CSF.

The value of assessment tests in patients with acute exacerbation of chronic obstructive pulmonary disease.

The aim of our study was to investigate the chronic obstructive pulmonary disease (COPD) assessment test (CAT), serum copeptin, procalcitonin and C-reactive protein (CRP) levels as potential predictive factors for recurrence of acute exacerbation and all-cause mortality in 6 months of COPD inpatients. One hundred fifty-nine patients who met the inclusion criteria were enrolled and followed up for 6 months. The CAT scores, serum copeptin, procalcitonin and CRP levels were measured on admission and 14 days and 3 months later in all patients. The primary endpoint was recurrence of acute exacerbation in 6 months. The secondary endpoint was all-cause mortality after 6 months. The CAT scores, serum copeptin, procalcitonin and CRP levels were significantly elevated on admission and stabilized at 14 days (P < 0.01). In a univariate logistic regression analysis, CAT scores (odds ratio [OR] = 1.10), forced expiratory volume in 1 second % (OR = 1.01), serum copeptin (OR = 1.32) and CRP levels (OR = 1.01) were significantly related to recurrence of acute exacerbation in 6 months (P < 0.05). In a multivariate logistic regression model, increasing CAT scores (OR = 1.10) and serum copeptin levels (OR = 1.29) were still associated with an increased odds of exacerbation (P < 0.05). In a univariate logistic regression analysis, increasing CAT scores (OR = 1.19), forced expiratory volume in 1 second % (OR = 1.05), serum copeptin levels (OR = 1.44) and hospitalization in the previous years (OR = 1.24) were significant determinants of death over a follow-up period of 6 months (P < 0.05). But only serum copeptin (OR = 1.53) and CAT scores (OR = 1.37) were associated with mortality in multivariate logistic regression analysis. Hence, high CAT scores and serum copeptin levels link with recurrence of acute exacerbation and all-cause mortality during 6 months in patients with acute exacerbation of COPD.

[Development of EV71, CA16 and other enterovirus vrial real-time qualitative PCR diagnostic kit].

OBJECTIVE: A novel multiplex real-time RT-PCR kit was developed to detect EV71, CoxA16 and other human enteroviruses simultaneously with an internal amplification control to avoids false negatives, which used for hand, foot and mouth disease in the clinical diagnosis and epidemiological surveillance. METHODS: Design specific primers and probes of EV71, CA16, other intestinal virus and internal amplification control, improve the extraction method of virus nucleic acid. Optimization the detection system of real-time quantitative PCR. Research the products of the accuracy, stability, precision, amplification efficiency and detection of linear range. RESULTS: The primers and probes had high spicificity. The Viral RNA extraction effect of this Kit is as same as that of QIAamp Viral RNA mini Kit (QIAGEN company), but less reagent cost. The optimal concentrations of primers and probes are 0.2 micromol/L for all the upstream and downstream primers, 0.06 micromol/L for probes of other human enteroviruse, 0.08 micromol/L for probes of EV71 and CA16 respectively. The kit has good stability, accuracy and precision. The amplification efficiencies of EV71, CoxA16 and other human enteroviruses are 106% ,101% and 105% and the detection of linear range is from 10(9) copies/microl-10(2) copies/microl. CONCLUSION: The novel multiplex real-time RT-PCR kit for detecting EV71, CoxA16 and other human enteroviruses simultaneously with an internal amplification control has good stability, accuracy, precision and amplification efficiencies. So it has great value in clinical application.

[Flexible bronchoscopic intervention for endobronchial hamartoma].

OBJECTIVE: To evaluate the effectiveness and safety of interventional treatment in the removal of endobronchial hamartoma by flexible bronchoscopy. METHODS: A retrospective analysis was conducted in 8 inpatients with histologically confirmed endobronchial hamartoma , diagnosed between May 2009 to January 2012 in the First Affiliated Hospital of Nanjing Medical University. The clinical, radiological and bronchoscopic features of hamartoma, and the clinical outcomes after bronchoscopic intervention were described. The endoscopic interventional treatments included resection by electrosurgical snare, electrocautery, argon plasma coagulation (APC) and cryotherapy. Thoracic computed tomography(CT)and bronchoscopy were used to evaluate the airway stenosis during follow-up. RESULTS: The 8 patients, 7 males and 1 female, aged (62 ± 8) years, underwent 13 times of interventional treatment for endobronchial hamartoma. Four patients were cured after receiving a single endoscopic treatment, while 3 patients had recurrence after initial interventional treatment but were cured after the second treatment. Three times of interventional treatment was carried out in 1 patient who had two relapses but later became stable with a 40% stenosis of the airway lumen. The rates of cure and effectiveness were 87.5% and 100%, respectively. Following interventional treatment, pneumothorax occurred in 1 patient who was cured after oxygen therapy. There were no serious complications such as massive haemorrhage, airway perforation, airway ignition and suffocation. CONCLUSION: Interventional treatments through flexible bronchoscopy appear to be safe and effective for removing endobronchial hamartoma.

Large scale preparation of midkine antisense oligonucleotides nanoliposomes by a cross-flow injection technique combined with ultrafiltration and high-pressure extrusion procedures.

The midkine antisense oligonucleotide (MK-ASODN, 5'-CCC CGG GCC GCC CTT CTT CA-3') nanoliposomes have been identified to suppress hepatocellular carcinoma (HCC) growth effectively, and have a great potential to be an effective target drug for HCC. In this study, a facile and reproducible method for large-scale preparation of MK-ASODN nanoliposomes followed by lyophilization has been developed successfully. Meanwhile, the MK-ASODN nanoliposomes characteristics, storage stability and their antitumor efficiency were studied. The mean particle size of MK-ASODN nanoliposomes were 229.43±15.11 nm, and the zeta potential were 29.7±1.1 mV. High entrapment efficiency values were achieved around 90%. Transmission electron microscopy images revealed spherical shaped nanoliposomes. Nanoliposomes allowed sustained MK-ASODN release for as long as 14 days. During 180 days of storage, freeze-dried nanoliposomes showed no significant change in the mean size, zeta potential, entrapment efficiency and drug release ratio. Regarding their antitumor efficiency, the in vitro proliferation of human liver cancer cells were significantly inhibited by the MK-ASODN nanoliposomes. Furthermore, the MK-ASOND nanoliposomes also significantly inhibited the growth of HCC in the mouse model. In summary, the results confirmed that this large-scale preparation of MK-ASOND nanoliposomes was facile and reproducible, and potentially, could speed up the application process of our MK-ASOND nanoliposomes for HCC therapy.