[Chiral separation of fourteen amino alcohols by nonaqueous capillary electrophoresis].

We developed a new method for chiral separation of fourteen amino alcohols by nonaqueous capillary electrophoresis (NACE) with the D-(+)-gluconic acid δ-lactone-boric acid complex as chiral selector. In order to achieve good enantioseparation, the effects of D-(+)-gluconic acid δ-lactone and boric acid concentrations, triethylamine concentration, as well as capillary temperature were systematically investigated. The optimized conditions were identified as follows: an uncoated fused silica capillary of 50 µm ID with a total length (L(tot)) of 55 cm and an effective length (L(eff)) of 45 cm; 200 mmol·L(-1) D-(+)-gluconic acid δ-lactone, 80 mmol·L(-1) boric acid, and 57.4 mmol·L(-1) triethylamine in methanol; positive pressure injection at 2.9 psi for 2 s; capillary temperature, 25 ± 0.2 ℃; applied voltage, +15 k V; detection wavelength, 214 nm. Under the optimized conditions, a good chiral resolution was achieved in most of the tested drugs. This method provides a foundation for the development and application of new chiral selectors of polyhydroxy compound-boric acid complexes in chiral drugs analysis by NACE.

A bibliometric analysis of anxiety and depression among primary school students.

Background: Rising anxiety and depression in primary school students adversely affect their development and academics, burdening families and schools. This trend necessitates urgent, focused research within this young demographic. This alarming trend calls for a systematic bibliometric analysis to develop effective preventative and remedial strategies. Objectives: This study aims to identify and analyze the prevailing research hotspots and emerging trends concerning anxiety and depression in primary school students, thereby furnishing a foundational reference for future academic endeavors in this area. Methods: This study uses the Web of Science (WOS) Core Collection database as the data source, focusing on literature published between 2013 and 2023 concerning anxiety and depression in primary school students. An initial search identified 1852 articles, which were then manually screened to exclude duplicates, conferences, announcements, and unrelated literature, resulting in 1791 relevant articles. The analysis, executed on December 31, 2023, employed CiteSpace and Vosviewer tools to assess various bibliometric indicators including authorship, country, institutional affiliations, publication trends, keyword frequency, and citation analysis. Results: The analysis revealed a corpus of 1,791 English-language articles, with a discernible upward trend in publications over the decade. The USA and China were the leading countries in this field, with 482and 272 papers, respectively. The research predominantly addresses the etiological factors of anxiety and depression, various intervention strategies, and the comorbidities associated with these conditions in the target population. Key research focuses have been identified in areas such as suicidal thoughts, bullying in schools, the impact of COVID-19, mindfulness interventions, and anxiety related to mathematics. Future research is projected to increasingly focus on the effects of mathematics anxiety on the psychological and behavioral outcomes in students. Conclusion: This study provides a critical visual and analytical overview of the key research areas and trends in the field of anxiety and depression among primary school students. It underscores the necessity of concentrating on the underlying causes and potential interventions. Such focused research is imperative for mitigating the mental health challenges faced by young students and enhancing their educational and developmental outcomes.

Cytotoxicity and apoptosis induced by nanobacteria in human breast cancer cells.

BACKGROUND: The existing evidence that nanobacteria (NB) are closely associated with human disease is overwhelming. However, their potential toxicity against cancer cells has not yet been reported. The objective of this study was to investigate the cytotoxic effects of NB and nanohydroxyapatites (nHAPs) against human breast cancer cells and to elucidate the mechanisms of action underlying their cytotoxicity. METHODOLOGY/PRINCIPAL FINDINGS: NB were isolated from calcified placental tissue, and nHAPs were artificially synthesized. The viability of the MDA-MB-231 human breast cancer cell line was tested by using the Kit-8 cell counting kit assay. Apoptosis was examined by transmission electron microscopy and flow cytometry. The endocytosis of NB and nHAPs by MDA-MB-231 cells was initially confirmed by microscopy. Although both NB and nHAPs significantly decreased MDA-MB-231 cell viability and increased the population of apoptotic cells, NB were more potent than nHAPs. After 72 hours, NB also caused ultrastructural changes typical of apoptosis, such as chromatin condensation, nuclear fragmentation, nuclear dissolution, mitochondrial swelling, and the formation of apoptotic bodies. CONCLUSION/SIGNIFICANCE: In MDA-MB-231 human breast cancer cells, NB and nHAPs exerted cytotoxic effects that were associated with the induction of apoptosis. The effects exerted by NB were more potent than those induced by nHAPs. NB cytotoxicity probably emerged from toxic metabolites or protein components, rather than merely the hydroxyapatite shells. NB divided during culturing, and similar to cells undergoing binary fission, many NB particles were observed in culture by transmission electron microscopy, suggesting they are live microorganisms.