BACKGROUND: Tidal peritoneal dialysis (TPD) provides better fluid flow mechanics and is more comfortable for the patient, owing to fewer alarms and less pain during inflow and outflow. The long-term characteristics of patients with TPD were not evident. In this randomized controlled follow-up study, we aimed to explore the characteristics of patients with TPD, compared to IPD.
METHODS: A total of 85 patients were randomized to either IPD or 70% TPD between January 2019 and December 2020, and all patients were followed up on December 2021. The characteristics of patients between the two groups were analyzed using a t-test or chi-square as appropriate. The overall survival and technical survival were analyzed using Kaplan-Meier analysis.
RESULTS: Forty-two patients were assigned to IPD, and 43 patients were assigned to TPD. The basal characteristics of patients were not different between the two groups. In an average of 16 months of follow-up, 19 patients died, and 25 patients dropped out of peritoneal dialysis. The two groups had no difference in overall survival and technical survival. TPD was associated with high urine volume (p = 0.001), lower blood urea nitrogen (p = 0.002), lower phosphorus (p = 0.004), and fewer cycler alarms (p < 0.001). The chance of patients reporting abdominal fullness was higher in patients with TPD (p = 0.001).
CONCLUSIONS: In the randomized, controlled, follow-up study, TPD may preserve residual renal function and is associated with lower urea nitrogen and phosphorus in chronic peritoneal dialysis patients. TPD is associated with fewer cycler alarms but may increase the chance of patients reporting abdominal distension.

Chronic obstructive pulmonary disease (COPD) is the most prevalent lung disease, and macrophages play a central role in the inflammatory response in COPD. We here report a comprehensive characterization of circulating short non-coding RNAs (sncRNAs) in plasma from patients with COPD. While circulating sncRNAs are increasingly recognized for their regulatory roles and biomarker potential in various diseases, the conventional RNA sequencing (RNA-seq) method cannot fully capture these circulating sncRNAs due to their heterogeneous terminal structures. By pre-treating the plasma RNAs with T4 polynucleotide kinase, which converts all RNAs to those with RNA-seq susceptible ends (5\'-phosphate and 3\'-hydroxyl), we comprehensively sequenced a wide variety of non-microRNA sncRNAs, such as 5\'-tRNA halves containing a 2\',3\'-cyclic phosphate. We discovered a remarkable accumulation of the 5\'-half derived from tRNAValCAC in plasma from COPD patients, whereas the 5\'-tRNAGlyGCC half is predominant in healthy donors. Further, the 5\'-tRNAValCAC half activates human macrophages via Toll-like receptor 7 and induces cytokine production. Additionally, we identified circulating rRNA-derived fragments that were upregulated in COPD patients and demonstrated their ability to induce cytokine production in macrophages. Our findings provide evidence of circulating, immune-active sncRNAs in patients with COPD, suggesting that they serve as inflammatory mediators in the pathogenesis of COPD.

Despite the increased use of diagnostic imaging in Africa, the completion of the Radiology Request Form (RRF) remains suboptimal, often relying on paper-based communication. To examine the practices surrounding RRF completion in the African continent, on 25 March 2024, we conducted a systematic review of peer-reviewed articles describing the practice in African settings. Non-African studies, studies involving non-human subjects, and articles examining the practice of the RRF for interventional usage were excluded. Our search involves PubMed/MEDLINE, ScienceDirect, Scopus, Web of Science, Google Scholar, and African Journals Online. The included studies were 3004, of which 30 met the inclusion criteria. These studies span eight countries and highlighted several shortcomings, including the usage of informal forms, unconventional abbreviations, illegibility, inaccuracy, and the lack of important fields from institutional forms, commonly the last menstrual period and the referrer\'s contact details. We also found widespread non-compliance in all RRF fields; half of the studies did not have an adequately filled form. Incomplete RRFs lead to delayed imaging, increased workloads for radiographers and radiologists, and potential misdiagnoses due to insufficient information. It will also impede the application of radiation protection principles. To address these challenges, empowering radiographers and radiologists and encouraging best practices is essential. Regular audits and educational initiatives aimed at clinicians are recommended. While transitioning to a paperless communication system might help, implementing nationwide quality improvement projects to standardise radiology request forms is currently more feasible.

Mycobacterium tuberculosis (Mtb) infection is among the world\'s deadliest infectious diseases. Developing effective treatments and biomarkers for tuberculosis requires a deeper understanding of its pathobiology and host responses. Here, we report a comprehensive characterization of circulating short non-coding RNAs (sncRNAs) in plasma samples from Mtb-infected patients. We achieved this by pre-treating plasma RNAs with T4 polynucleotide kinase to convert all RNA ends to those compatible with sncRNA sequencing. We discovered a global and drastic upregulation of plasma sncRNAs in Mtb-infected patients, with tRNA-derived sncRNAs representing the most dramatically elevated class. Most of these tRNA-derived sncRNAs originated from a limited subset of tRNAs, specifically from three tRNA isoacceptors, and exhibited skewed patterns to 5\'-derived fragments, such as 5\' halves, 5\' tRNA fragments (tRFs), and internal tRFs (i-tRFs) from the 5\' regions. Further, Mtb-infected patients displayed markedly upregulated and distinct profiles of both rRNA- and mRNA-derived sncRNAs. Some of these sncRNAs, which are abundant and specific to Mtb-infected patients, robustly activated human macrophages via Toll-like receptor 7 and induced cytokine production. This drastic accumulation of circulating, immunostimulatory sncRNAs in the plasma of Mtb-infected patients offers insights into the sncRNA-driven aspects of host immune response against infectious diseases and suggests a pool of potential therapeutic targets and biomarkers.

Translation of messenger RNA (mRNA) in bacteria occurs in the steps of initiation, elongation, termination, and ribosome recycling. The initiation step comprises multiple stages and uses a special transfer RNA (tRNA) called initiator tRNA (i-tRNA), which is first aminoacylated and then formylated using methionine and N10 -formyl-tetrahydrofolate (N10 -fTHF), respectively. Both methionine and N10 -fTHF are produced via one-carbon metabolism, linking translation initiation with active cellular metabolism. The fidelity of i-tRNA binding to the ribosomal peptidyl-site (P-site) is attributed to the structural features in its acceptor stem, and the highly conserved three consecutive G-C base pairs (3GC pairs) in the anticodon stem. The acceptor stem region is important in formylation of the amino acid attached to i-tRNA and in its initial binding to the P-site. And, the 3GC pairs are crucial in transiting the i-tRNA through various stages of initiation. We utilized the feature of 3GC pairs to investigate the nuanced layers of scrutiny that ensure fidelity of translation initiation through i-tRNA abundance and its interactions with the components of the translation apparatus. We discuss the importance of i-tRNA in the final stages of ribosome maturation, as also the roles of the Shine-Dalgarno sequence, ribosome heterogeneity, initiation factors, ribosome recycling factor, and coevolution of the translation apparatus in orchestrating a delicate balance between the fidelity of initiation and/or its leakiness to generate proteome plasticity in cells to confer growth fitness advantages in response to the dynamic nutritional states.

In translation initiation in prokaryotes, IF3 recognizes the interaction between the initiator codon of mRNA and the anticodon of fMet-tRNAini and then relocates the fMet-tRNAini to an active position. Here, we have surveyed 328 codon-anticodon combinations for the preference of IF3. At the first and second base of the codon, only Watson-Crick base pairs are tolerated. At the third base, stronger base pairs, for example, Watson-Crick, are more preferred, but other types of base pairs, for example, G/U wobble, are also tolerated; weaker base pairs are excluded by IF3. When the codon-anticodon combinations are unfavorable for IF3 or the concentration of IF3 is too low to recognize any codon-anticodon combinations, IF3 fails to set the P-site fMet-tRNAini at the active position and causes its drop-off from the ribosome. Thereby, translation reinitiation occurs from the second aminoacyl-tRNA at the A site to yield a truncated peptide lacking the amino-terminal fMet. We refer to this event as the amino-terminal drop-off-reinitiation. We also showed that EF-G and RRF are involved in disassembling such an aberrant ribosome complex bearing inactive fMet-tRNAini Thereby EF-G and RRF are able to exclude unfavorable codon-anticodon combinations with weaker base pairs and alleviate the amino-terminal drop-off-reinitiation.

Determination of impurity level in weight percent against the claimed active pharmaceutical ingredient (API) in a drug product is of critical importance in drug development. However, authentic material used to determine relative UV response factor (RRF) for impurity quantitation is sometimes not available or not stable. In a particular drug product liquid formulation, three degradants, including one unstable impurity, are consistently observed in stability studies. Here we describe the application of NMR spectroscopy to assist in the determination of RRFs, simultaneously, for all three degradants directly from degraded drug product extracts. This technique was not only effective in determining RRF of an unstable substance, but also in defining RRFs of multiple degradants from a single drug product sample. Overall, this study continues to demonstrate the capabilities of NMR for impurity quantitation in drug development.

Mitochondrial disorders are often difficult to diagnose because of diverse clinical phenotypes. FGF-21 and GDF-15 are metabolic hormones and promising biomarkers for the diagnosis of these disorders. This study has systematically evaluated serum FGF-21 and GDF-15 levels by ELISA in a well-defined cohort of patients with definite mitochondrial disorders (n = 30), neuromuscular disease controls (n = 36) and healthy controls (n = 36) and aimed to ascertain their utility in the diagnosis of mitochondrial disorders. Both serum FGF-21 and GDF-15 were significantly elevated in patients with mitochondrial disorders, especially in those with muscle involvement. The levels were higher in patients with mitochondrial deletions (both single and multiple) and translation disorders compared to respiratory chain subunit or assembly factor defects.

Acinetobacter baumannii is an important pathogen in hospital acquired infections. Although tigecycline currently remains a potent antibiotic for treating infections caused by multidrug resistant A. baumannii (MDRAB) strains, reports of tigecycline resistant isolates have substantially increased. The resistance mechanisms to tigecycline in A. baumannii are far more complicated and diverse than what has been described in the literature so far. Here, we characterize in vitro-selected MDRAB strains obtained by increasing concentrations of tigecycline. We have identified mutations in adeS, rrf and rpoB that result in reduced susceptibility to tigecycline. Using in situ complementation experiments, we confirm that mutations in rrf, rpoB, and two types of mutations in adeS correlate with tigecycline resistance. By Western blot and polysome profile analysis, we demonstrate that the rrf mutation results in decreased expression of RRF, which affects the process of ribosome recycling ultimately leading to increased tigecycline tolerance. A transcriptional analysis shows that the mutated rpoB gene plays a role in regulating the expression of the SAM-dependent methyltransferase (trm) and transcriptional regulators, to confer moderate tigecycline resistance. This study provides direct in vitro evidence that mutations in the adeS, rpoB and rrf are associated with tigecycline resistance in A. baumannii.

We used ribosome profiling to characterize the biological role of ribosome recycling factor (RRF) in Escherichia coli. As expected, RRF depletion leads to enrichment of post-termination 70S complexes in 3\'-UTRs. We also observe that elongating ribosomes are unable to complete translation because they are blocked by non-recycled ribosomes at stop codons. Previous studies have suggested a role for recycling in translational coupling within operons; if a ribosome remains bound to an mRNA after termination, it may re-initiate downstream. We found, however, that RRF depletion did not significantly affect coupling efficiency in reporter assays or in ribosome density genome-wide. These findings argue that re-initiation is not a major mechanism of translational coupling in E. coli. Finally, RRF depletion has dramatic effects on the activity of ribosome rescue factors tmRNA and ArfA. Our results provide a global view of the effects of the loss of ribosome recycling on protein synthesis in E. coli.