The prevalence of neck pain among online learning students: An observational study.

Neck pain is among the most prevalent musculoskeletal disorders affecting the general population. During the 2019 coronavirus disease 2019 (COVID-19) pandemic, students have increasingly resorted to online learning, requiring prolonged use of electronic devices. This study aimed to investigate the prevalence of and factors influencing neck pain during online learning. The study employed a cross-sectional design. Eligible participants were nursing students who had been receiving online instruction for a duration exceeding 3 months. To develop the study instrument, the researchers integrated the study objectives with insights from an extensive literature review. This process culminated in the creation of a comprehensive online questionnaire designed to capture relevant data. The prevalence of neck pain among students was analyzed for both the pre-COVID-19 and during COVID-19 periods. The chi-square test was utilized to compare the occurrence of neck pain between these 2 periods, while binary logistic regression was employed to examine the association between various influencing factors and neck pain. This study revealed that out of the 426 students who participated in the study, 391 were female (91.8%) and 35 were male (8.2%). The prevalence of neck pain during online learning (62.7%) was significantly higher than before online learning (37.3%) (P < .05). A significant correlation was also found between neck pain and learning while lying on a bed or table, duration of use of electronic devices, and exercising habits (P < .05). The prevalence of neck pain among students has significantly increased during the COVID-19 pandemic. Future research should focus on evaluating the long-term impact of distance learning on undergraduate students. Additionally, it is imperative to develop and implement targeted intervention programs based on the identified influencing factors to mitigate the prevalence of neck pain and alleviate neck discomfort.

Corybungines A-K: Isoquinoline alkaloids from Corydalis bungeana with dopamine D2 receptor activity.

Eleven undescribed isoquinoline alkaloids corybungines A-K including a protoberberine-type alkaloid, an isoquinoline alkaloid with a unique 6-norprotoberberine skeleton, one 13,14-seco-protoberberine-type alkaloid, two 1a,14-seco-protoberberine-type alkaloids with a 4-(hydroxymethyl)phenoxy moiety and six aporphine alkaloids, together with seven known alkaloids, have been isolated from the whole herb extract of Corydalis bungeana Turcz. Their structures and absolute configurations were elucidated based on an analysis of spectroscopic data and electronic circular dichroism (ECD) spectra. (R)-stephanine displayed high antagonistic activity against the dopamine D2 receptor with an IC50 value of 0.85 ± 0.09 µM in CHO-D2 cells. Additionally, corybungines D, F, H, (R)-roemerine, (R)-vireakine and (R)-tuduranine showed moderate D2 antagonism (IC50 5.20-26.07 µM). The preliminary structure-activity relationships (SARs) of aporphine alkaloids were discussed.

Structurally diverse isoquinoline and amide alkaloids with dopamine D2 receptor antagonism from Corydalis bungeana.

Four new isoquinoline alkaloids including a benzophenanthridine alkaloid (1), a morphine derivative (2), a narceine-type alkaloid (3) and a simple isoquinoline alkaloid (4), a new amide alkaloid (5) and a new phthalic acid derivative (6), together with eleven known alkaloids (7-17) were obtained from the whole herbs extract of Corydalis bungeana Turcz. Their structures and absolute configurations were elucidated by extensive spectroscopic data analysis including HRESIMS, NMR and electronic circular dichroism (ECD) and ECD calculation. Compounds 1-17 were evaluated for dopamine D2 receptor activity in CHO-D2 cells. Among them, 16 showed the highest antagonistic activity on the D2 receptor with an IC50 value of 2.04 ± 0.01 µM. Compounds 14 and 15 exhibited moderate antagonism with IC50 values of 13.66 ± 2.28 and 31.72 ± 2.52 µM, respectively.