A Triplex PCR Method for Distinguishing the Wild-Type African Swine Fever Virus From the Deletion Strains by Detecting the Gene Insertion.

To date, there is no effective vaccine or antiviral therapy available to prevent or treat African swine fever virus (ASFV) infections. ASFV gene deletion strains have been proposed as promising anti-ASFV vaccine candidates. In recent years, most ASFV gene deletion strains worldwide have been recombinant strains expressing EGFP or mCherry as markers. Therefore, in this study, a new triplex real-time PCR (RT-PCR) method was established for the broad and accurate differentiation of ASFV wild-type vs. gene deletion strains. We designed three pairs of primers and probes to target B646L, EGFP, and mCherry, and RT-PCR was used to detect these three genes simultaneously. The detection method prevented non-specific amplification of porcine reproductive and respiratory syndrome virus, porcine epidemic diarrhea virus, circovirus type 2, pseudorabies virus, and classical swine fever virus genes. The minimum copy number of standard plasmid DNA detected using triplex RT-PCR was 9.49, 15.60, and 9.60 copies for B646L, EGFP, and mCherry, respectively. Importantly, of the 1646 samples analyzed in this study, 67 were positive for ASFV, all corresponding to the wild-type virus. Overall, our data show that the triplex RT-PCR method established in this study can specifically identify both ASFV wild-type and gene deletion strains.

Clinical Efficacy of CT-Guided Continuous Catheterization Drainage for Spinal Tuberculosis with Large Abscesses.

OBJECTIVE: This study aimed to determine the efficacy of computed tomography (CT)-guided local catheterization for the treatment of spinal tuberculosis (TB) with abscess. METHODS: Clinical data from 22 cases of lumbar TB with abscess receiving treatments from July 2015 to January 2021 were analyzed. Some patients (n = 11) underwent pure surgery (control group) and the others (n = 11) received CT-guided catheterization drainage. The operation and hospitalization time, erythrocyte sedimentation rate (ESR), visual analog scale (VAS), ASIA damage grade, and C-reactive protein (CRP) levels of both groups were compared. RESULTS: The operation time, intraoperative blood loss, and hospital stay of the observation group were significantly less than those of the control group (P < 0.05). As the differences in preoperative ESR, CRP, and VAS scores between both groups did not reach significance (P > 0.05), after treatments, the observation group had a lower level of ESR and CRP (P < 0.05); the postoperative VAS scores of the two groups decreased (P > 0.05). Before treatment, the control group comprised 2 cases of ASIA grade A, 1 case of B, 6 cases of C, and 2 cases of D with 3 patients having dyskinesia. After surgery, the motor function of the patients was improved, and there were 3 cases of ASIA D and 8 cases of E. Meanwhile, the preoperative observation group consisted of 9 cases of ASIA D and 2 cases of E. Due to CT-guided catheterization, all patients achieved clinical healing (ASIA E) when the lesions were significantly alleviated, and symptoms such as low back pain and lower extremity pain disappeared. CONCLUSION: CT-guided percutaneous catheter drainage for continuous administration of drugs is effective treatment for spinal TB with abscess, when shortening the operation and hospitalization time and reducing intraoperative blood loss and erythrocyte sedimentation rate. It is worthy of popularization and application.

GS-441524 inhibits African swine fever virus infection in vitro.

African swine fever virus (ASFV) is a highly infectious and lethal swine pathogen that causes serious socio-economic consequences in endemic countries for which no safe and effective vaccine is currently available. GS-441524, a 1-cyano-substituted adenine C-nucleoside ribose analogue, inhibits viral RNA transcription by competing with natural nucleosides (ATP, TTP, CTP, and GTP) and effectively inhibits viral RNA-dependent RNA polymerase activity. However, whether GS-441524 can inhibit the replication of DNA viruses is unknown. In this study, we confirmed that GS-441524 inhibits ASFV infection in porcine alveolar macrophages (PAMs) in a dose-dependent manner; GS-441524 significantly inhibited ASFV replication at different time points after ASFV infection, particularly at the early stages of viral replication. Notably, GS-441524 did not increase the levels of antiviral cytokines or ATP in PAMs. However, an increase in the concentration of natural ATP in PAMs promoted the replication of ASFV and attenuated the inhibitory effect of GS-441524 in a dose-dependent manner. Our results suggest that GS-441524 is an effective antiviral against ASFV.