Sampling strategy for bacteriological diagnosis of intrathoracic tuberculosis.

BACKGROUND: Pulmonary tuberculosis (TB) is the most frequent site of TB and the one leading its spread worldwide. Multiple specimens are commonly collected for TB diagnosis including those requiring invasive procedures. This study aimed to review the sampling strategy for the microbiological diagnosis of pulmonary TB. METHODS: A retrospective analysis of collected samples from September 1st 2014 to May 1st 2016 in the Bacteriology laboratory of Pitié-Salpêtrière Hospital (Paris, France) was performed. All the samples collected in patients aged over 18 years for the bacteriological diagnosis of pulmonary TB were included. RESULTS: A total of 6267 samples were collected in 2187 patients. One hundred and twenty-six patients (6%) had a culture confirmed pulmonary TB. Among them, multiple sputum collections were sufficient for TB diagnosis in 63.5%, gastric lavages permitted to avoid bronchoscopy in only 7.1%, and bronchoscopy was necessary in 29.4%. The culture positivity of sputa (8.6%) was higher than that of bronchial aspirations (3.1%), bronchiolo-alveolar lavages (BAL) (2.3%) or gastric lavages (4.8%) (P<0.001). From its 70.0% theoretical PPV value, the 46.1% selection in bronchial aspirations allocated to molecular test increased PPV up to 88.9%. CONCLUSIONS: Based on our data, we suggest to collect sputum consistently. If smear negative a bronchoscopy should be performed and molecular diagnosis be performed on a subset of bronchial aspirations based on expertise of the bronchoscopist.

[Analysis of bacterial communities of two Lake Baikal endemic sponge species].

Bacterial diversity of two Lake Baikal endemic sponges characterized by different life forms, branching Lubomirskia baicalensis and cortical Baikalospongia sp., was studied using the method of 454 pyrosequencing of the 16S rRNA gene fragments. In the communities associated with L. baicalensis and Baikalospongia sp., 426 and 428 OTUs, respectively, were identified. In microbial associations of these spong- es, 24 bacterial phyla were identified, with predominance of Bacteroidetes, Proteobacteria, and Actinobacteria. Analysis of the taxonomic composition of bacterial communities of the sponges was carried out by search of the dominant phylotypes within the phylum level cluster. Comparison of bacterial associations of the sponges with Lake Baikal bacterioplankton revealed both the shared OTUs and the unique ones characteristic of the studied species.

Effect of sodium chloride and nitroprusside on protein carbonyl groups content and antioxidant enzyme activity in leaves of corn seedlings Zea mays L.

The effect of sodium nitroprusside (SNP) and sodium chloride (NaCl) on protein carbonyl group content and activity of antioxidant enzymes was investigated in leaves of maize seedlings. Incubation with NaCl and SNP+NaCl increased the content of carbonyl proteins after 24 h. Treatment with SNP+NaCl during 48 h showed lower and after 72 h higher carbonyl protein content than that in the control. Catalase activity was higher in the leaves of SNP+NaCl-treated than in the leaves of SNP-treated seedlings after 24 h. Ascorbate peroxidase activity increased after incubation with 0.2 mM SNP for 24 h. Significant increment of guaiacol peroxidase activity was obtained in all treated groups in comparison with the control after 72 h. Glutathione-S-transferase activity increased after 48 h seedling treatment with NaCl or SNP and 72 h seedling incubation with NaCl. Under experimental conditions used, glutathione reductase activity was virtually not affected. It is proposed that SNP can be used to prevent salt-induced oxidative stress in maize.