The application of quantitative telomerase activity measurement as an important indicator to monitor the cardiomyocyte differentiation process of human induced pluripotent stem cells under defined conditions.

The construction of an in vitro differentiation system for human induced pluripotent stem cells (hiPSCs) has made exciting progress, but it is still of great significance to clarify the differentiation process. The use of conventional genetic and protein-labeled microscopes to observe or detect different stages of hiPSC differentiation is not specific enough and is cumbersome and time-consuming. In this study, in addition to analyzing the expression of gene/protein-related markers, we used a previously reported simple and excellent quantitative method of cellular telomerase activity based on a quartz crystal microbalance (TREAQ) device to monitor the dynamic changes in cellular telomerase activity in hiPSCs during myocardial differentiation under chemically defined conditions. Finally, by integrating these results, we analyzed the relationship between telomerase activity and the expression of marker genes/proteins as well as the cell type at each study time point. This dynamic quantitative measurement of cellular telomerase activity should be a promising indicator for monitoring dynamic changes in a stage of hiPSC differentiation and inducing cell types. This study provided a quantitative, dynamic and simple monitoring index for the in vitro differentiation process of hiPSC-CMs, which was a certain reference value for the optimization and improvement of the induction system.

AMPKα1 overexpression improves postoperative cognitive dysfunction in aged rats through AMPK-Sirt1 and autophagy signaling.

Postoperative cognitive dysfunction (POCD) is a common complication in elderly patients who undergo surgery involving anesthesia. Its underlying mechanisms remain unclear. Autophagy plays an important role in the damage and repair of the nervous system and is associated with the development of POCD. Using a rat model, adenosine monophosphate-activated protein kinase α1 (AMPKα1), an important autophagy regulator, was found to be significantly downregulated in rats with POCD that was induced by sevoflurane anesthesia or by appendectomy. Overexpression of AMPKα1-ameliorated POCD, as indicated by decreased escape latencies and increased target quadrant swimming times, swimming distances, and platform crossing times during Morris water maze tests. AMPKα1 overexpression activated autophagy signals by increasing the expression of light chain 3 II (LC3-II) and Beclin1 and decreasing the expression of p62 in the hippocampus of rats with POCD. Moreover, blocking autophagy by 3-methyladenine partly attenuated AMPKα1-mediated POCD improvement. Furthermore, overexpression of AMPKα1 could upregulate the expression of p-AMPK and Sirt1 in the hippocampus of rats with POCD. Intriguingly, inhibiting AMPK signals via Compound C effectively attenuated AMPKα1-mediated POCD improvement, concomitant with the downregulation of p-AMPK, Sirt1, LC3-II, and Beclin1 and the upregulation of p62. We thus concluded that overexpression of AMPKα1 can improve POCD via the AMPK-Sirt1 and autophagy signaling pathway.

Association of the incidence of postherpetic neuralgia with early treatment intervention of herpes zoster and patient baseline characteristics: a systematic review and meta-analysis of cohort studies.

OBJECTIVE: To conduct a meta-analysis of the association between postherpetic neuralgia (PHN), baseline characteristics of patients with herpes zoster (HZ), and early interventions. METHODS: Literature searches were conducted in seven databases, in June 2021 and updated in June 2022. Two investigators independently conducted literature screening and data extraction, and the studies were evaluated according to the Newcastle-Ottawa Scale. RESULTS: A total of 53 cohort studies were included. The meta-analyses identified skin lesions, timing of initial treatment (≥ 3 days), and comorbidities as potential risk factors for PHN. In contrast, female sex (odds ratio [OR] = 1.13, 95% confidence interval [CI]: 0.99-1.29), cervical herpes (OR = 0.80, 95% CI: 0.21-2.99), lumbar herpes (OR = 1.29, 95% CI: 0.61-2.74), and immunosuppressive therapy (OR = 1.96, 95% CI: 0.22-17.12), were not significantly associated with PHN. In addition, glucocorticoid use (OR = 0.61, 95% CI: 0.22-1.70) may be a protective factor for the development of PHN; however, the difference was not statistically significant. CONCLUSION: A series of baseline characteristics were identified among populations at high risk of developing PHN from HZ. Additionally, the timing of initial treatment is associated with PHN occurrence. The preventive effect of glucocorticoids warrants further validation.

Generation of an S100B homozygous knockout pluripotent stem cell line (WAe009-A-94) by the CRISPR/Cas9 system.

S100 calcium binding protein beta (S100B) is an S-100 low molecular weight binding protein that regulates intracellular processes. This protein is involved in myocardial contractility and calcium handling capacity. In this study, a human embryonic stem cell (hESC) line with homozygous S100B knockout (S100B-KO) was generated using the CRISPR/Cas9 editing system. This S100B-KO hESC line maintained normal cell morphology and karyotype, expressed pluripotency markers, and could differentiate into cells of all three germ layers.

Small-Dose Ropivacaine Hydrochloride with Fentanyl versus Large-Dose of Ropivacaine Hydrochloride for Cesarean Section.

OBJECTIVE: To compare the effect of small-dose ropivacaine hydrochloride combined with fentanyl versus large-dose of ropivacaine hydrochloride for cesarean section. STUDY DESIGN: Experimental study. PLACE AND DURATION OF STUDY: Department of Anesthesiology, Gansu People's Hospital, China, from February 2017 to April 2018. METHODOLOGY: A total of 134 maternal women, who underwent cesarean section, were randomly divided into control group and observation group, with 67 cases in each group. Control group was anesthetized with a large dose (1.5 mL) of ropivacaine hydrochloride, and observation group was anesthetized with a small dose (1 mL) of ropivacaine hydrochloride in combination with 10 µg of fentanyl. Then anesthetic effects of the two groups were compared. RESULTS: The onset time of anesthesia and postoperative pain scores of the anesthesia in observation group were better than those in control group (both p<0.001). There was no significant difference in HR, SpO2 and MAP between the two groups after 15 minutes of anesthesia, and after the operation (p=0.393, 0.275, 0.108, 0.740, 0.068 and 0.230, respectively). After the delivery of the fetuses, the HR, SpO2 and MAP of the parturients in observation group were better than those in control group (all p<0.001). Frequency of adverse reactions of parturients in observation group was lower than that in control group (p=0.033). CONCLUSION: In comparison to large-dose of ropivacaine hydrochloride, small-dose of ropivacaine hydrochloride combined with fentanyl, in combined spinal-epidural analgesia on parturients accepting cesarean section, can more effectively maintain their hemodynamic stability, relieve postoperative pain, and have a low incidence of adverse reactions.

Sirt3-Mediated Autophagy Contributes to Resveratrol-Induced Protection against ER Stress in HT22 Cells.

Endoplasmic reticulum (ER) stress occurring in stringent conditions is critically involved in neuronal survival and death. Resveratrol is a non-flavonoid polyphenol that has neuroprotective effects against many neurological disorders. Here, we investigated the potential protective effects of resveratrol in an in vitro ER stress model mimicked by tunicamycin (TM) treatment in neuronal HT22 cells. We found that TM dose-dependently decreased cell viability and increased apoptosis, which were both significantly attenuated by resveratrol treatment. Resveratrol markedly reduced the expression or activation of ER stress-associated factors, including GRP78, CHOP, and caspase-12. The results of immunocytochemistry and western blot showed that resveratrol promoted autophagy in TM-treated cells, as evidenced by increased LC3II puncta number, bcelin1 expression and LC3II/LC3I ratio. Pretreatment with the autophagy inhibitor chloroquine could reduce the protective effects of resveratrol. In addition, the expression of Sirt3 protein and its downstream enzyme activities were significantly increased in resveratrol-treated HT22 cells. To confirm the involvement of Sirt3-mediated mechanisms, siRNA transfection was used to knockdown Sirt3 expression in vitro. The results showed that downregulation of Sirt3 could partially prevented the autophagy and protection induced by resveratrol after TM treatment. Our study demonstrates a pivotal role of Sirt3-mediated autophagy in mediating resveratrol-induced protection against ER stress in vitro, and suggests the therapeutic values of resveratrol in ER stress-associated neuronal injury conditions.

One-Step Synthesis of Chiral Oxindole-type Analogues with Potent Anti-inflammatory and Analgesic Activities.

Here we report a facile approach to synthesize highly optically active oxindole-type analogues with both high yield and enantioselectivity. This single-step synthesis strategy represents a substantial improvement upon existing methods that are often involved with multi-step routes and have suboptimal atomic economy. One such compound, namely Q4c, showed remarkable in vivo anti-inflammatory activity with efficiency approaching to that of a steroidal compound dexamethasone. Moreover, Q4c alleviated pain in mouse models with comparable activity to morphine. Further investigation suggested that nitric oxide signaling pathway is involved in the anti-inflammatory and analgesic activities of Q4c. Notably, this is the first time that chiral oxindole-type analogues have been identified to be both anti-inflammatory and analgesic, and our study also paved the way for future development of oxindoles as drug candidates in this field.