Honeybee symbiont Bombella apis could restore larval-to-pupal transition disrupted by antibiotic treatment.

Numerous studies have demonstrated the vital roles of gut microbes in the health, immunity, nutrient metabolism, and behavior of adult worker honeybees. However, a few studies have been conducted on gut microbiota associated with the larval stage of honeybees. In the present study, we explored the role of a gut bacterium in larval development and larval-pupal transition in the Asian honeybee, Apis cerana. First, our examination of gut microbial profiling showed that Bombella apis, a larvae-associated bacterium, was the most dominant bacterium colonized in the fifth instar larvae. Second, we demonstrated that tetracycline, an antibiotic used to treat a honeybee bacterial brood disease, could cause the complete depletion of gut bacteria. This antibiotic-induced gut microbiome depletion in turn, significantly impacted the survivorship, pupation rate and emergence rate of the treated larvae. Furthermore, our analysis of gene expression pattens revealed noteworthy changes in key genes. The expression of genes responsible for encoding storage proteins vitellogenin (vg) and major royal jelly protein 1 (mrjp1) was significantly down-regulated in the tetracycline-treated larvae. Concurrently, the expression of krüppel homolog 1(kr-h1), a pivotal gene in endocrine signaling, increased, whilethe expression of broad-complex (br-c) gene that plays a key role in the ecdysone regulation decreased. These alterations indicated a disruption in the coordination of juvenile hormone and ecdysteroid synthesis. Finally, we cultivated B. apis isolated from the fifth instar worker larval of A. cerana and fed tetracycline-treated larvae with a diet replenished by B. apis. This intervention resulted in a significant improvement in the pupation rate, emergence rate, and overall survival rate of the treated larvae. Our findings demonstrate the positive impact of B. apis on honeybee larvae development, providing new evidence of the functional capacities of gut microbes in honeybee growth and development.

Molecular characterization and phylogenetic analysis of fowl adenovirus serotype-4 from Guangdong Province, China.

AIM: Our aim in this study was to isolate potentially novel strains of fowl adenovirus serotype-4 (FAdV-4) that is currently circulating in broiler chicken flocks in Guangdong Province, China, and to compare nucleotide and amino acid (AA) sequences of their respective hexon genes. MATERIALS AND METHODS: The experiment was carried out on poultry farms experiencing outbreaks of FAdV-4-associated hydropericardium syndrome (HPS). Tissue samples from the hearts and livers of deceased chickens were screened for FAdV-4 infection using hexon gene-specific polymerase chain reaction (PCR). RESULTS: New virus isolates were used to infect 7-day-old chicks, which went onto reproduce typical HPS signs. The hypervariable region of the FAdV-4 hexon gene was PCR-amplified and sequenced. The hexon nucleotide and deduced AA sequence identities were 99.8-99.9% and 99.5-99.8%, respectively, among the four novel isolates. In addition, the new isolates were 97-100% and 96.4-99.9% identical to the nucleotide and deduced AA sequences, respectively, of FAdV-4 hexon genes available in the National Center for Biotechnology Information GenBank database. Phylogenetic analyses, based on the hexon gene sequence, revealed that the new isolates, clustered with FAdV-C; the FAdV-A, FAdV-B, FAdV-D, and FAdV-E viruses, were more distantly related. CONCLUSION: New FAdV-4 isolates from Guangdong Province are similar to those identified in other regions of the world. This information provides critical insight into HPS epidemiology and provides a perspective for monitoring outbreaks and developing strategies for disease prevention.

Tumor shrinkage rate as a potential marker for the prediction of long-term outcome in advanced non-small cell lung cancer treated with first-line tyrosine kinase inhibitors.

CONTEXT: Tyrosine kinase inhibitors (TKIs) targeting epidermal growth factor receptor (EGFR) play an indispensable role in the treatment of non-small cell lung cancer (NSCLC), leading to a survival major breakthrough, but there remains no uniform standard for predicting the efficacy of TKI therapy. AIMS: We retrospectively reviewed the use of EGFR-TKIs for advanced NSCLC between January 2009 and December 2017 in a hospital, which 169 patients who treated with first-line TKIs were enrolled. SUBJECTS AND METHODS: Multiple clinical factors, including histology, age, and sex, were analyzed. We calculated the tumor shrinkage rate (TSR) by measuring the longest diameters of the main mass by computed tomography (CT) before TKI therapy and the first CT after TKI therapy. We evaluated overall survival (OS) and progression-free survival (PFS) after first-line TKI therapy, and we assessed factors predicting survival using the Kaplan-Meier method. RESULTS: Eligible patients were sorted into higher (n = 83) and lower (n = 86) TSR groups according to the mean TSR of 0.49%. The 83 patients with a higher TSR had longer PFS and OS than those in the 86 patients with a lower TSR (14.83 vs. 8.40 months, P < 0.001, and 31.03 vs. 20.10 months, P < 0.001, respectively). Multivariate analyses revealed that TSR was an independent predictor of PFS and OS (PFS hazard ratio [HR]: 0.506, P < 0.001, and OS HR: 0.291, P < 0.001). CONCLUSIONS: These cumulative data support that TSR may be an early predictor of the treatment efficacy in NSCLC with EGFR mutations treated with first-line TKIs.