Study protocol: a pragmatic, cluster-randomized controlled trial to evaluate the effect of implementation of the Truenat platform/MTB assays at primary health care clinics in Mozambique and Tanzania (TB-CAPT CORE).

BACKGROUND: In 2020, the WHO-approved Molbio Truenat platform and MTB assays to detect Mycobacterium tuberculosis complex (MTB) and resistance to rifampicin directly on sputum specimens. This primary health care center-based trial in Mozambique and Tanzania investigates the effect of Truenat platform/MTB assays (intervention arm) combined with rapid communication of results compared to standard of care on TB diagnosis and treatment initiation for microbiologically confirmed TB at 7 days from enrolment. METHODS: The Tuberculosis Close the Gap, Increase Access, and Provide Adequate Therapy (TB-CAPT) CORE trial employs a pragmatic cluster randomized controlled design to evaluate the impact of a streamlined strategy for delivery of Truenat platform/MTB assays testing at primary health centers. Twenty-nine centers equipped with TB microscopy units were selected to participate in the trial. Among them, fifteen health centers were randomized to the intervention arm (which involves onsite molecular testing using Truenat platform/MTB assays, process process optimization to enable same-day TB diagnosis and treatment initiation, and feedback on Molbio platform performance) or the control arm (which follows routine care, including on-site sputum smear microscopy and the referral of sputum samples to off-site Xpert testing sites). The primary outcome of the study is the absolute number and proportion of participants with TB microbiological confirmation starting TB treatment within 7 days of their first visit. Secondary outcomes include time to bacteriological confirmation, health outcomes up to 60 days from first visit, as well as user preferences, direct cost, and productivity analyses. ETHICS AND DISSEMINATION: TB-CAPT CORE trial has been approved by regulatory and ethical committees in Mozambique and Tanzania, as well as by each partner organization. Consent is informed and voluntary, and confidentiality of participants is maintained throughout. Study findings will be presented at scientific conferences and published in peer-reviewed international journals. TRIAL REGISTRATION: US National Institutes of Health's ClinicalTrials.gov, NCT04568954. Registered 23 September 2020.

Drosophila Antimicrobial Peptides and Lysozymes Regulate Gut Microbiota Composition and Abundance.

The gut microbiota affects the physiology and metabolism of animals and its alteration can lead to diseases such as gut dysplasia or metabolic disorders. Several reports have shown that the immune system plays an important role in shaping both bacterial community composition and abundance in Drosophila, and that immune deficit, especially during aging, negatively affects microbiota richness and diversity. However, there has been little study at the effector level to demonstrate how immune pathways regulate the microbiota. A key set of Drosophila immune effectors are the antimicrobial peptides (AMPs), which confer defense upon systemic infection. AMPs and lysozymes, a group of digestive enzymes with antimicrobial properties, are expressed in the gut and are good candidates for microbiota regulation. Here, we take advantage of the model organism Drosophila melanogaster to investigate the role of AMPs and lysozymes in regulation of gut microbiota structure and diversity. Using flies lacking AMPs and newly generated lysozyme mutants, we colonized gnotobiotic flies with a defined set of commensal bacteria and analyzed changes in microbiota composition and abundance in vertical transmission and aging contexts through 16S rRNA gene amplicon sequencing. Our study shows that AMPs and, to a lesser extent, lysozymes are necessary to regulate the total and relative abundance of bacteria in the gut microbiota. We also decouple the direct function of AMPs from the immune deficiency (IMD) signaling pathway that regulates AMPs but also many other processes, more narrowly defining the role of these effectors in the microbial dysbiosis observed in IMD-deficient flies upon aging. IMPORTANCE This study advances current knowledge in the field of host-microbe interactions by demonstrating that the two families of immune effectors, antimicrobial peptides and lysozymes, actively regulate the gut microbiota composition and abundance. Consequences of the loss of these antimicrobial peptides and lysozymes are exacerbated during aging, and their loss contributes to increased microbiota abundance and shifted composition in old flies. This work shows that immune effectors, typically associated with resistance to pathogenic infections, also help shape the beneficial gut community, consistent with the idea that host-symbiont interactions use the same "language" typically associated with pathogenesis.

Expression of CK-19 and CEA mRNA in peripheral blood of gastric cancer patients.

AIM: To investigate the clinical and pathological relevance of detection of circulating tumor cells (CTC) in the peripheral blood of gastric carcinoma patients before operation. PATIENTS AND METHODS: Fifty patients with gastric adenocarcinoma were analysed prospectively. Patients were divided into two groups according to the extent of the tumor. Group I (unresectable) consisted of 22, and group II (resectable) consisted of 28 patients. Peripheral blood samples were collected pre-operatively from all 50 patients as well as from ten healthy controls and analyzed for carcinoembryonic antigen (CEA) and cytokeratin-19 (CK-19) messenger ribonucleic acids (mRNAs). Tumor localisation, stage, presence of signet cell formation, nodal metastases, serousal and lymphovascular invasion were recorded for all patients. RESULTS: Expression of CK-19 was detected in 24 (48%), and CEA in 10 (20%) cases. Nine patients (40%) in group I and 15 (53.6%) in group II were positive for CK-19 expression. CEA expression was more frequent among group I patients (6 vs. 4 cases). There was no significant difference between the groups in the expression of CK-19 and CEA mRNA, tumor localisation, presence of signet formation, and presence and extent of nodal metastases. Patients with major vascular invasion (MVI) expressed significantly higher levels of CTC mRNA compared to those without MVI (p = 0.023 for CEA, and p = 0.009 for CK-19). The median 1 and 2-year survival was 9.5 and 10.5 months for group I, and 20 and 28.5 months for group II, respectively (p = 0.001). The mean survival was 6.7 months for patients with MVI, and 30.2 months for those without MVI (p = 0.0001). CONCLUSIONS: High levels of CTCs were observed in patients with MVI invasion, rather than other causes of unresectability. It can be suggested that expression of both CEA and CK-19 in the peripheral blood of gastric cancer patients are strong predictors of MVI and significantly worse survival rates.