Background: Rising global temperatures have been linked to an increased incidence of heat stress (HS)-induced myocardial damage. Methods: This study aimed to investigate the therapeutic potential of shikimic acid (SA) on HS-induced myocardial damage using network pharmacology, molecular docking, molecular dynamics (MD) simulations, and in vitro experiments. Results: Network pharmacology analysis indicated that SA significantly attenuates the inflammatory response to HS by modulating 60 targets, including TNF, IL-6, and STAT3, which are enriched in the PI3K/AKT signaling pathway. Molecular docking and MD simulation analyses demonstrated that SA forms stable complexes with TNF (−6.642 kcal/mol) and IL-6 (−7.261 kcal/mol), with no significant conformational changes over a 100 ns simulation period. In vitro experiments demonstrated that SA, within the concentration range of 250 μM to 31.25 μM, significantly promoted the proliferation of normal HL-1 cells by an average of 31.0%. Moreover, it enhanced the survival rate of HL-1 cells exposed to 43 °C for 3 h by approximately 59.9% and downregulated the expression of Hsp90 and Hsp70. Additionally, this concentration range of SA reduced the expression of TNF-α, IL-6, TLR2, and COL1A1. Conclusions: These findings offer evidence for the therapeutic potential of SA in HS-induced myocardial damage.

Proteus mirabilis is a zoonotic pathogen that poses a growing threat to both animal and human health due to rising antimicrobial resistance (AMR). It is widely found in animals, including China’s nationally protected captive giant and red pandas. This study isolated Proteus mirabilis from panda feces to assess AMR and virulence traits, and used whole-genome sequencing (WGS) to evaluate the spread of resistance genes (ARGs) and virulence genes (VAGs). In this study, 37 isolates were obtained, 20 from red pandas and 17 from giant pandas. Multidrug-resistant (MDR) strains were present in both hosts. Giant panda isolates showed the highest resistance to ampicillin and cefazolin (58.8%), while red panda isolates were most resistant to trimethoprim/sulfamethoxazole (65%) and imipenem (55%). Giant panda-derived strains also exhibited stronger biofilm formation and swarming motility. WGS identified 31 ARGs and 73 VAGs, many linked to mobile genetic elements (MGEs) such as plasmids, integrons, and ICEs. In addition, we found frequent co-localization of drug resistance genes/VAGs with MGEs, indicating a high possibility of horizontal gene transfer (HGT). This study provides crucial insights into AMR and virulence risks in P. mirabilis from captive pandas, supporting targeted surveillance and control strategies.

Since 2013, a dengue epidemic has broken out in Yunnan, China and neighboring countries. However, after the COVID-19 pandemic in 2019, the number of dengue cases decreased significantly. In this retrospective study, epidemiological and genetic diversity characterizations of dengue viruses (DENV) isolated in Yunnan between 2017 and 2018 were performed. The results showed that the dengue outbreak in Yunnan from 2017 to 2018 was mainly caused by DENV1 (genotype I and genotype V) and DENV2 (Asia I, Asia II, and Cosmopolitan). Furthermore, correlation analysis indicated a significant positive correlation between the number of imported and local cases (correlation coefficient = 0.936). Multiple sequence alignment and phylogenetic divergence analysis revealed that the local isolates are closely related to the isolates from Myanmar and Laos. Interestingly, recombination analysis found that the DENV1 and DENV2 isolates in this study had widespread intra-serotype recombination. Taken together, the results of the epidemiological investigation imply that the dengue outbreak in Yunnan was primarily due to imported cases. This study provides a new reference for further investigations on the prevalence and molecular epidemiology of DENV in Yunnan, China.

The elderly population is particularly susceptible to myocardial damage caused by heat stress (HS). With the continuous increase in global temperatures, this poses an undeniable challenge to human health. This study aimed to investigate the therapeutic effect of Shikimic Acid (SA) in treating HS-induced myocardial damage through network pharmacology, molecular docking, molecular dynamics (MD) simulations, and in vitro experiments. Network pharmacology analysis revealed that SA alleviates the inflammatory response in the heart muscle associated with HS by targeting 60 disease-related targets, such as TP53, TNF, and IL-6. The tumor proteoglycan, the PI3K-Akt signaling pathway, and hepatitis B were identified as the primary therapeutic pathways. Molecular docking and MD simulation results confirmed that SA can stably bind to both TNF (-6.642 kcal/mol) and IL-6 (-7.261 kcal/mol), and the complexes of Shikimic Acid-IL-6 and Shikimic Acid-TNF did not undergo significant changes within 100 ns. In addition, the in vitro experiment showed that 250 μM SA significantly increased the survival rate of HL-1 cells exposed to 43°C for 2 h by 71.1% and promoted the proliferation of HL-1 cells by 30.7%. Overall, these findings provide substantial evidence for the therapeutic potential of SA in HS-induced myocardial damage.

Canine circovirus (CanineCV) is a recently identified member of the Circoviridae family. Since its discovery in 2011, CanineCV has been detected in different countries worldwide, infecting both domestic and wild canids. The virus is potentially associated with gastrointestinal and respiratory illnesses. In 2016, CanineCV was reported in the southwestern region of Guangxi, China. However, its prevalence in other provinces in the Southwest region remained unknown. This study collected a total of 208 serum samples from domestic dogs in Sichuan, China in 2022 to investigate the prevalence of CanineCV. Among these samples, 26 tested positive for CanineCV, resulting in a positivity rate of 12.5%. Additionally, 12 strains were sequenced, 9 of which had a sequence length of 2,063 nucleotides (nt), 2 of the other threes had a length of 2,062 nts and another was 2,064 nt. Notably, a frameshift mutation was identified, resulting in a truncated ORF1 and the occurrence of a novel sequence comprised of 13 amino acids at the end of the replicate protein (Rep). This mutation could affect the replication cycle of the virus. Phylogenetic and evolutionary analyses revealed that the isolates belonged to the CanineCV-3 genotype and were prevalent in the Southeast and the Southwest regions of China, as well as in the neighboring countries alongside other strains of the same genotype. Collectively, this epidemiological investigation widens our understanding of the genetic diversity of CanineCV in Southwest China and provides insights into viral evolution.

Three pathogenic species of the genus Yersinia, including Plague-associated Yersinia pestis, Yersinia pseudotuberculosis, and Yersinia enterocolitica, are commonly associated with human infection. Current qPCR detection methods are mainly limited to the identification of one or two Yersinia species in a single reaction tube, while multiplex assays for multiple genera have been more commonly reported. Therefore, the present study aimed to establish a multiplex TaqMan qPCR assay for the simultaneous detection of these three pathogenic Yersinia species. Primer and probe sets were designed based on the inv gene for Y. pseudotuberculosis, the caf1 gene for Y. pestis, and the foxA gene for Y. enterocolitica. Under the optimized reaction conditions, the standard curve slopes for the caf1, inv, and foxA genes were −3.046, −2.968, and −2.948, respectively. The correlation coefficients (R²) ranged from 0.993 to 0.996, while the amplification efficiencies ranged from 109% to 115%. The limits of detection (LOD) were determined to be 5 × 10² copies/μL for inv (FAM), 1 × 10¹ copies/μL for caf1 (ROX), and 1 × 10¹ copies/μL for foxA (CY5). The sensitivity of the multiplex qPCR assay was 10- to 100-fold higher than that of conventional PCR, depending on the target. Specificity experiments demonstrated that no cross-reactivity was observed with non-target bacteria, including Francisella tularensis, Brucella spp., Vibrio cholerae, Salmonella Typhi, and Shigella spp. The intra-assay coefficients of variation (CVs) ranged from 0.13% to 0.79%, whereas the inter-assay CVs ranged from 0.62% to 2.61%. Among 173 spleen samples collected from wild rodents, no positive signal for Y. pestis or Y. pseudotuberculosis was detected. In contrast, Y. enterocolitica was detected in three samples (1.73%, 3/173). In conclusion, the multiplex qPCR assay developed in this study provides a sensitive and specific tool for the simultaneous detection of three pathogenic Yersinia species and has the potential to improve detection efficiency in clinical and epidemiological investigations.