The tympanic membrane (TM) forms an impenetrable barrier to medical therapies for middle ear (ME) diseases like otitis media. By screening a phage-displayed peptide library, we have previously discovered rare peptides that mediate the active transport of cargo across the intact membrane of animals and humans. Since the M13 filamentous bacteriophage on which the peptides are expressed are large (nearly 1 µm in length), this offers the possibility of noninvasively delivering drugs, large drug packages, or gene therapy to the ME. To evaluate this possibility, EDC chemistry was employed to covalently attach amoxicillin, or neomycin molecules to phage bearing a trans-TM peptide, as a model for large drug packages. Eight hours after application of antibiotic-phage to the TM of infected rats, ME bacterial titers were substantially reduced compared to untreated animals. As a control, antibiotic was linked to wild-type phage, not bearing any peptide, and application to the TM did not affect ME bacteria. The results support the ability of rare peptides to actively deliver pharmacologically relevant amounts of drugs through the intact TM and into the ME. Moreover, since bacteriophage engineered to express peptides are viral vectors, the trans-TM peptides could also transport other viral vectors into the ME.
Niger has the world's highest fertility rate, with about seven children per woman, significantly impacting maternal and child health. This study examines how fertility-related attitudes and social norms affect adolescent wives' (AWs) fertility desires in rural Niger. Using data from 768 AWs (ages 15-19), their husbands, and mothers-in-law, the study employed multilevel linear regression models to analyse associations between birth spacing attitudes, social norms, and AWs' fertility desires. Results show a significant link between social norms and wives' fertility desires. Wives with pro-natalist descriptive and injunctive norms and those whose husband has pro-natalist injunctive norms have higher fertility desire. Interestingly, individual attitudes weren't directly correlated with fertility desires, suggesting social norms predominate over personal attitudes. The study further highlights that village-level descriptive norms are significantly associated with fertility desires. It underscores the need for interventions that address social contexts within communities, not just individual-level activities. The research emphasises the complexity of these norms, considering multiple perspectives, and highlights husbands' influence on wives' fertility intentions. Recommendations include community-based programs engaging various stakeholders and policy initiatives promoting women's agency and rights.
Obstructive sleep apnea (OSA) is characterized by intermittent hypoxia/hypercapnia (IHC), affects predominantly obese individuals, and increases atherosclerosis risk. Since we and others have implicated gut microbiota and metabolites in atherogenesis, we dissected their contributions to OSA-induced atherosclerosis. Atherosclerotic lesions were compared between conventionally-reared specific pathogen free (SPF) and germ-free (GF) Apoe-/- mice following a high fat high cholesterol diet (HFHC), with and without IHC conditions. The fecal microbiota and metabolome were profiled using 16S rRNA gene amplicon sequencing and untargeted tandem mass spectrometry (LC-MS/MS) respectively. Phenotypic data showed that HFHC significantly increased atherosclerosis as compared to regular chow (RC) in both aorta and pulmonary artery (PA) of SPF mice. IHC exacerbated lesions in addition to HFHC. Differential abundance analysis of gut microbiota identified an enrichment of Akkermansiaceae and a depletion of Muribaculaceae (formerly S24-7) family members in the HFHC-IHC group. LC-MS/MS showed a dysregulation of bile acid profiles with taurocholic acid, taurodeoxycholic acid, and 12-ketodeoxycholic acid enriched in the HFHC-IHC group, long-chain N-acyl amides, and phosphatidylcholines. Interestingly, GF Apoe-/- mice markedly reduced atherosclerotic formation relative to SPF Apoe-/- mice in the aorta under HFHC/IHC conditions. In contrast, microbial colonization did not show a significant impact on the atherosclerotic progression in PA. In summary, this research demonstrated that (1) IHC acts cooperatively with HFHC to induce atherosclerosis; (2) gut microbiota modulate atherogenesis, induced by HFHC/IHC, in the aorta not in PA; (3) different analytical methods suggest that a specific imbalance between Akkermansiaceae and Muribaculaceae bacterial families mediate OSA-induced atherosclerosis; and (4) derived bile acids, such as deoxycholic acid and lithocholic acid, regulate atherosclerosis in OSA. The knowledge obtained provides novel insights into the potential therapeutic approaches to prevent and treat OSA-induced atherosclerosis.
Non-coding RNAs (ncRNAs) are finely tuned cellular regulators important for human cell growth and cancer progression. DUBR (Dppa2 upstream binding RNA, also known as linc00883) is a nuclear ncRNA first discovered in mice for its role in regulating myoblast differentiation through interactions with chromatin and DNA methyltransferases. High expression levels of this ncRNA are predictive of poor patient outcome in colon adenocarcinoma, suggesting that DUBR may be involved in controlling cancer growth. To elucidate its function, we used RAP-MS and RNA immunoprecipitation techniques which revealed its interaction with epigenetic maintenance proteins in the human colon cancer cell line HCT116. Further, ATAC-seq and RNA-seq were used to address its function in regulating the epigenome and transcriptome of HCT116 cells. Here we report that DUBR is a regulator of human colon cancer cell line HCT116 survival. Additionally, we find that the ncRNA DUBR regulates AP-1 transcription factor binding site accessibility at enhancers of genes involved in differentiation and morphogenesis through interactions with epigenetic proteins such as NuRD complex members HDAC1 and CHD4.
Isoprenol (3-methyl-3-buten-1-ol) is a precursor to aviation fuels and other commodity chemicals and can be microbially synthesized from renewable carbon streams. Its production has been demonstrated in Pseudomonas putida KT2440 but its titers, rates, and yields have yet to reach commercially viable levels, potentially due to toxicity to the bacterial chassis. We hypothesized that utilization of Tolerization Adaptive Laboratory Evolution (TALE) would generate P. putida hosts more tolerant to isoprenol and suitable for enhanced production phenotypes. Here, we performed a comprehensive TALE campaign using three strains, the wild-type and two strains lacking subsets of known isoprenol catabolism and transport functions in quadruplicate independently evolved lineages. Several evolved clones from each starting strain displayed robust growth (up to 0.2 h-1) at 8 g/L of isoprenol, where starting strains could not grow. Whole genome resequencing of the 12 independent strain lineages identified convergent mutations. Reverse engineering each of the four commonly mutated regions individually (gnuR, ttgB-PP_1394, PP_3024-PP_5558, PP_1695) resulted in a partial recovery of the tolerance phenotypes observed in the evolved strains. Additionally, a proteomics-guided deletion of the master motility regulator, fleQ, in an evolved clone alleviated the tolerance vs. production trade-off, restoring isoprenol titers and consumption to levels observed in the starting strains. Collectively, this work demonstrated that an integrated strategy of laboratory evolution and rational engineering was effective to develop robust biofuel production hosts with minimized product toxicity.
During aging, the cardiac extracellular matrix (ECM) undergoes gradual remodeling that reduces the heart's ability to function. Specific ECM changes cause alterations in cellular signaling pathways, eliciting maladaptive responses. Here, we provide insight into the current knowledge of how age-specific ECM changes contribute to altered ligand-receptor interactions, dysregulated mechanotransduction, and the propagation of pro-fibrotic signaling cascades that underpin dysfunction. We also highlight regional and sex differences that new biomolecular and bioengineered technologies have recently uncovered. We call for new biomaterial strategies that mimic spatiotemporal and sex-specific ECM alterations to equip researchers with the tools to unravel complex cellular signaling events. We believe this can be achieved through interdisciplinary cooperation amongst researchers spanning matrix biology, biomaterials, spatial omics, and biomedical engineering.
