Early detection and follow-up of colorectal neoplasia based on faecal volatile organic compounds.

AIM: Early detection and removal of colorectal cancer (CRC) and advanced adenomas (AAs) decreases the incidence of and mortality from the disease. We aimed to evaluate the potential of faecal volatile organic compounds (VOCs) for detection and follow-up of colorectal adenoma using advanced electronic nose technology. METHOD: This was a prospective multi-centre case-control cohort including two district hospitals and one tertiary referral hospital. Patients undergoing colonoscopy were instructed to collect a faecal sample prior to bowel cleansing and were included in the study when CRC, AAs, large adenomas (LAs; 0.5-1.0 cm), small adenomas (SAs; 0.1-0.5 cm) or no endoscopic abnormalities (controls) were observed. Patients undergoing polypectomy and controls were asked for a second sample after 3 months. Faecal VOCs were measured with gas chromatography-ion mobility spectrometry. Random forest, support vector machine, Gaussian process and neural net classification were used to evaluate accuracy. RESULTS: In total, 14 patients with CRC, 64 with AAs, 69 with LAs, 127 with SAs and 227 controls were included. A second sample was collected from 32 polypectomy patients and 32 controls. Faecal VOCs discriminated CRC and adenomas from control [AUC (95% CI): CRC vs control 0.96 (0.89-1); AA vs control 0.96 (0.93-1); LA vs control 0.96 (0.92-0.99); SA vs control 0.96 (0.94-0.99)]. There were no significant differences between CRC and adenoma groups. Patients with adenomas and controls were discriminated prior to polypectomy, whereas 3 months after polypectomy VOC profiles were similar [T0 adenoma vs control 0.98 (0.95-1); T1 adenoma vs control 0.55 (0.40-0.69)]. CONCLUSIONS: Faecal VOC profiles may be useful for early detection of CRC and adenomas and the timing of polyp surveillance as polypectomy led to a normalization of the VOC profile.

The expanding role of endobronchial ultrasound in patients with centrally located intrapulmonary tumors.

OBJECTIVES: Tissue acquisition of lung tumors is crucial for diagnostic and treatment purposes. In patients with centrally located lung tumors without endobronchial abnormalities the yield of conventional bronchoscopy is poor. Objective of this study was to assess diagnostic yield of EBUS-TBNA in patients with lung tumors, located near or adjacent to the major airways. METHODS: International multicenter retrospective analysis (2013-2018) of linear EBUS databases in Bologna, Italy and Amsterdam, The Netherlands. Patients with a centrally-located lung tumor without endobronchial abnormalities who underwent lung tumor search with linear EBUS were included. Diagnostic yield, feasibility of EBUS guided tumor sampling, complication rate, adequacy of the aspirates for mutational analysis, and assessment of mediastinal/vascular invasion (T4) were evaluated. RESULTS AND CONCLUSION: Real-time EBUS-TBNA diagnostic yield to sample centrally located intrapulmonary tumor was 83% (136/163) and it was independent of tumor location (paratracheal, mainstem, lobar, segmental bronchus). The feasibility to sample the lung tumor was 89% (145/163). In 4 cases the tumor was not found with EBUS. In the other 14 cases, tumor sampling was not performed due to: loss of the echo window after needle insertion [n = 3], interposition of a large vessel [n = 7], switch to radial EBUS [n = 1], switch and sampling through EUS or EUS-B [n = 3]. No major complications occurred. Mutational analysis was successful in 54/63 (86%) of samples. Using surgery as reference standard, EBUS proved more reliable than CT (24/24, 100% versus 22/24, 91.7%, respectively) in the assessment of mediastinal/vascular tumor invasion (T4 status). IN CONCLUSION: Lung tumors presenting without endobronchial abnormalities and located adjacent to the major airways can be safely sampled by EBUS-TBNA resulting in high diagnostic yield irrespective of tumor location. Successful molecular profiling and reliable assessment of mediastinal/vascular invasion (T4) in patients with advanced disease provide additional value to EBUS procedures in the setting of centrally-located lung lesions.

Safety and Tolerability of Nebulized Amoxicillin-Clavulanic Acid in Patients with COPD (STONAC 1 and STONAC 2).

The safety and tolerability of nebulized amoxicillin clavulanic acid were determined in patients with stable COPD and during severe exacerbations of COPD. Nine stable COPD patients received doses ranging from 50:10 mg up to 300:60 mg amoxicillin clavulanic acid and eight patients hospitalised for a COPD exacerbation received fixed doses 200/40 mg twice daily. Safety was evaluated by spirometry before and after inhalation. Tolerability was evaluated by questionnaire. Plasma and expectorated sputum samples were assayed for amoxicillin content. Seventeen patients underwent in total 100 nebulizations with amoxicillin clavulanic acid. In this safety and tolerability study no clinically relevant deteriorations in FEV1 were observed. Nebulized amoxicillin clavulanic acid produces sputum concentrations well above the Minimal Inhibiting Concentration of 90% for potential pathogenic micro-organisms, with low concentrations in the central compartment (low systemic exposure). Based on spirometry and reported side effects, inhalation of nebulized amoxicillin clavulanic acid seems to be safe and well tolerated, both in stable patients with COPD as in those experiencing a severe exacerbation. Levels of amoxicillin were adequate.

Analysis of the role of the gene bipA, encoding the major endoplasmic reticulum chaperone protein in the secretion of homologous and heterologous proteins in black Aspergilli.

The function of the endoplasmic-reticulum-localized chaperone binding protein (BiP) in relation to protein secretion in filamentous fungi was studied. It was shown that the overproduction of several homologous and heterologous recombinant proteins by Aspergillus strains induces the expression of bipA, the BiP-encoding gene from Aspergillus niger and Aspergillus awamori. As this result could imply that BiP plays a role in protein overproduction, the effect of modulation of bipA gene expression on protein secretion was studied in several recombinant strains expressing glucoamylase (glaA) fusion genes. For overproduction of BiPA in these strains, extra copies of the bipA gene under the control of an inducible promoter were introduced. To allow analysis of the effect of a decreased bipA expression level on protein secretion, replacement of the wild-type gene for a bipA gene driven by the glaA promoter was attempted. However, this endeavour failed because of the lethality of this replacement. Although the final amount of secreted recombinant protein did not change significantly in strains with increased BiPA levels, increased levels of unprocessed fusion protein were detected in the total protein extracts of these strains.

Isolation and characterization of the Aspergillus niger trpC gene.

The Aspergillus niger trpC gene was isolated by complementation experiments with an Escherichia coli trpC mutant. Plasmid DNA containing the A. niger trpC gene transforms an Aspergillus nidulans mutant strain, defective in all three enzymatic activities of the trpC gene, to Trp+, indicating the presence of a complete and functional trpC gene. Southern blot analysis of DNA from these Trp+ transformants showed that plasmid DNA was present but that this DNA was not integrated at the site of the chromosomal trpC locus. The A. niger trpC gene was localized on the cloned fragment by heterologous hybridization experiments and sequence analysis. These experiments suggest that the organization of the A. niger trpC gene is identical to that of the analogous A. nidulans trpC and the Neurospora crassa trp-1 genes.