SUMMARY Sepsis is a life-threatening inflammatory syndrome accompanying a bloodstream infection. Frequently secondary to pathogenic bacterial infections, sepsis remains difficult to treat as a singular disease mechanism. We compared the pathogenesis of murine sepsis experimentally elicited by five bacterial pathogens and report similarities among host responses to Gram-negative Salmonella and E. coli. We observed that a host protective mechanism involving de-toxification of lipopolysaccharide by circulating alkaline phosphatase (AP) isozymes was incapacitated during sepsis caused by Salmonella or E. coli through activation of host Toll-like receptor 4, which triggered Neu1 and Neu3 neuraminidase induction. Elevated neuraminidase activity accelerated the molecular aging and clearance of AP isozymes, thereby intensifying disease. Mice deficient in the sialyltransferase ST3Gal6 displayed increased disease severity, while deficiency of the endocytic lectin hepatic Ashwell-Morell receptor was protective. AP augmentation or neuraminidase inhibition diminished inflammation and promoted host survival. This study illuminates distinct routes of sepsis pathogenesis, which may inform therapeutic development.

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Glycosidases are hydrolytic enzymes studied principally in the context of intracellular catabolism within the lysosome. Therefore, glycosidase activities are classically measured in experimentally acidified assay conditions reflecting their low pH optima. However, glycosidases are also present the bloodstream where they may retain sufficient activity to participate in functions including the regulation of glycoprotein half-lives, proteostasis, and disease pathogenesis. We have herein established at physiological pH 7.4 in blood plasma and sera the normal ranges of four major glycosidase activities essential for blood glycoprotein remodeling in healthy mice and humans. These activities included β-galactosidase, β-N-acetylglucosaminidase, α-mannosidase, and α-fucosidase. We have identified their origins to include the mammalian genes Glb1, HexB, Man2a1, and FucA1. In experimental sepsis, excursions of glycosidase activities occurred with differences in host responses to discrete bacterial pathogens. Among similar excursions in human sepsis, the elevation of β-galactosidase activity was a prognostic indicator of increased likelihood of patient death.

Background The opioid epidemic is a progressively worsening public health crisis that continues to impact healthcare system strategies such as overdose reversal and destigmatization. Even among healthcare professionals, there remains a lack of confidence in naloxone administration and a prevalence of stigma. While training can play a major impact in reducing these shortcomings, the long-term effectiveness has yet to be characterized in training healthcare professionals. This study examined the long-term retention of opioid overdose awareness and reversal training (OOART) by evaluating performance at two-time intervals, immediately post-training and at a 3-month follow-up. Methods Voluntary training was offered to first-year (M1) medical students at the Drexel University College of Medicine in 2021. At this training, 118 students completed training, 95 completed the post-training survey, and 42 completed the 3-month follow-up. Results Opioid reversal knowledge questions assessed significantly increased scores post-training and at the 3-month follow-up. In three of the attitude questions, scores were improved at both follow-up timepoints. In addition, three attitude questions indicating a participant’s confidence to respond to an opioid overdose situation increased directly after the training, but regressed at the 3-month follow-up. The remaining questions did not show any statistical difference across the survey intervals. Conclusions This study establishes that while OOART provides participants with the knowledge of how to respond to an opioid overdose, the retention of this knowledge at a 3-month interval is reduced. The results were mixed for longitudinal assessment of participant’s attitudes toward people with opioid use disorder. Some positive increases in attitudes were retained at the 3-month interval, while others trended back toward pre-training levels. These results support the effectiveness of the training but also provide evidence that OOART must be reinforced often.