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Coupling reagents play crucial roles in the iterative construction of amide bonds for the synthesis of peptides and peptide‐based derivatives. The novel DIC/Oxyma condensation system featured with the low risk of explosion displayed remarkable abilities to inhibit racemization, along with efficient coupling efficiency in both manual and automated syntheses. Nevertheless, an ideal reaction molar ratio in DIC/Oxyma condensation system and the moderate reaction temperature by manual synthesis remain to be further investigated. Herein, the synthetic efficiencies of different reaction ratios between DIC and Oxyma under moderate reaction temperature were systematically evaluated. The robustness and efficiency of DIC/Oxyma condensation system are validated by the rapid synthesis of linear centipede toxin RhTx. Different folding strategies were applied for the construction of disulfide bridges in RhTx, which was further confirmed in assays of circular dichroism and patch‐clamp electrophysiology evaluation. This work establishes the DIC/Oxyma‐based accelerated synthesis of peptides under moderate condensation conditions, which is especially useful for the manual synthesis of peptides. Besides, the strategy presented here provides robust technical supports for the large‐scale synthesis and oxidative folding of RhTx. [ABSTRACT FROM AUTHOR]

The article discusses the correlation between growth hormone (GH) gene single nucleotide polymorphisms (SNPs) and traits of milk production in 232 Chinese Holstein cows using polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) method.

Background: Targeted temperature management (TTM), as a therapeutic temperature control strategy for cardiac arrest (CA), is recommended by guidelines. However, the relationship between post-rewarming fever (PRF) and the prognosis of CA patients is unclear. Therefore, we aim to summarize the studies regarding the influence of PRF on patients with CA., Methods: EMBASE, PubMed, and Cochrane Central databases were searched from inception to March 13, 2022. Randomized clinical trials (RCTs) and cohort studies on PRF in CA patients were included. According to the heterogeneity, the meta-analysis was performed using a random effects model or fixed effects model to calculate the pooled odds ratios ( ORs ) and corresponding 95% confidence intervals ( CI s). The outcome data were unfavorable neurological outcome and mortality., Results: The meta-analysis included 11 observational studies involving 3,246 patients. The results of the meta-analysis show that PRF (body temperature >38.0 °C) has no effect on the neurological outcome of CA patients ( OR 0.71, 95% CI 0.43-1.17, I 2 82%) and has a significant relationship with lower mortality ( OR 0.63; 95% CI 0.49-0.80, I 2 39%). However, PRF with a stricter definition (body temperature >38.5 °C ) was associated with worse neurological outcome ( OR 1.44, 95% CI 1.08-1.92, I 2 45%) and higher mortality ( OR 1.71, 95% CI 1.25-2.35, I 2 47%)., Conclusion: This study suggests that PRF >38.0 °C may not affect the neurological outcome and have a lower mortality in CA patients who completed TTM. However, PRF >38.5 °C is a potential prognostic factor for worse outcomes in CA patients., Competing Interests: Conflicts of interest: The authors have no conflicts of interest to disclose., (Copyright: © World Journal of Emergency Medicine.)

Objective: To study the effect of cone angle on fracture resistance force of root and post-core system., Methods: Forty-two simulated tooth roots made of polymethacrylate (PMMA) were divided into six groups according to the root canal cone angles of 0 degrees, 3.93 degrees, 5.71 degrees, 7.48 degrees, 11.31 degrees and 14.71 degrees. Cast post and cores were manufactured and cemented with zinc polycarboxylate cement (PC). Casting the post and core to restore every simulated tooth root. Each specimen was embedded in acrylic resin and then fixed in a special jig on the universal load-testing machine. A compressive load was applied at a 90-degree angle to the long axis of the core until fracture, at a crosshead speed of 1 mm/min. The maximum of load was recorded., Results: The mean values of load in root and post-core system were 0.1225 kN, 0.1498 kN, 0.1600 kN, 0.1893 kN, 0.1078 kN and 0.0945 kN. There were significant differences in the fracture resistance among groups., Conclusion: The fracture resistance force of cast post and core increased with the enlargement of post cone angles under certain conditions.