Taste buds relay taste sensory information to the primary taste neurons but depend on those same neurons for essential components to maintain function. While denervation-induced taste bud degeneration and subsequent regeneration were discovered decades ago, the mechanisms underlying these phenomena (e.g., heterogenous cellular responses to nerve injury and the signaling pathways involved) remain poorly understood. Here, using mouse genetics, nerve injury models, pharmacologic manipulation, and taste bud organoid models, we identify a specific subpopulation of taste cells, predominantly c-Kit-expressing sweet cells, that exhibit superior resistance to nerve injury. We found the c-Kit inhibitor imatinib selectively reduced the number of residual c-Kit-expressing sweet cells at post-operation week 2, subsequently attenuating the re-emergence of other type II cells by post-operation week 4. In taste bud organoids, c-Kit-expressing cells were resistant to R-spondin withdrawal but susceptible to imatinib, while other taste cell types showed the opposite behavior. We also observed a distinct population of residual taste cells that acquired stem-like properties, generating clonal descendent cells among suprabasal keratinocytes independent of c-Kit signaling. Together, our findings reveal that c-Kit signaling confers resilience on c-Kit-expressing sweet cells and supports the broader reconstruction of taste buds during the later regenerative stage following nerve injury.
Animals ; Taste Buds/metabolism* ; Proto-Oncogene Proteins c-kit/metabolism* ; Mice ; Signal Transduction ; Imatinib Mesylate/pharmacology* ; Mice, Inbred C57BL

Taste sensation is the gatekeeper for direct decisions on feeding behavior and evaluating the quality of food. Nutritious and beneficial substances such as sugars and amino acids are represented by sweet and umami tastes, respectively, whereas noxious substances and toxins by bitter or sour tastes. Essential electrolytes including Na+ and other ions are recognized by the salty taste. Gustatory information is initially generated by taste buds in the oral cavity, projected into the central nervous system, and finally processed to provide input signals for food recognition, regulation of metabolism and physiology, and higher-order brain functions such as learning and memory, emotion, and reward. Therefore, understanding the peripheral taste system is fundamental for the development of technologies to regulate the endocrine system and improve whole-body metabolism. In this review article, we introduce previous widely-accepted views on the physiology and genetics of peripheral taste cells and primary gustatory neurons, and discuss key findings from the past decade that have raised novel questions or solved previously raised questions.

Taste sensation is the gatekeeper for direct decisions on feeding behavior and evaluating the quality of food. Nutritious and beneficial substances such as sugars and amino acids are represented by sweet and umami tastes, respectively, whereas noxious substances and toxins by bitter or sour tastes. Essential electrolytes including Na+ and other ions are recognized by the salty taste. Gustatory information is initially generated by taste buds in the oral cavity, projected into the central nervous system, and finally processed to provide input signals for food recognition, regulation of metabolism and physiology, and higher-order brain functions such as learning and memory, emotion, and reward. Therefore, understanding the peripheral taste system is fundamental for the development of technologies to regulate the endocrine system and improve whole-body metabolism. In this review article, we introduce previous widely-accepted views on the physiology and genetics of peripheral taste cells and primary gustatory neurons, and discuss key findings from the past decade that have raised novel questions or solved previously raised questions.

Objective: No studies have evaluated the diagnostic value of ischemia-modified albumin (IMA) for the early detection of sepsis/septic shock in patients presenting to the emergency department (ED). We aimed to assess the usefulness of IMA in diagnosing sepsis/septic shock in the ED. Methods: This retrospective, observational study analyzed IMA, lactate, high sensitivity C-reactive protein, and procalcitonin levels measured within 1 hour of ED arrival. Patients with suspected infection meeting at least two systemic inflammatory response syndrome criteria were included and classified into the infection, sepsis, and septic shock groups using Sepsis-3 definitions. Areas under the receiver operating characteristic curves (AUCs) with 95% confidence intervals (CIs) and multivariate logistic regression were used to determine diagnostic performance. Results: This study included 300 adult patients. The AUC (95% CI) of IMA levels (cut-off ≥85.5 U/mL vs. ≥87.5 U/mL) was higher for the diagnosis of sepsis than for that of septic shock (0.729 [0.667–0.791] vs. 0.681 [0.613–0.824]) and was higher than the AUC of procalcitonin levels (cut-off ≥1.58 ng/mL, 0.678 [0.613–0.742]) for the diagnosis of sepsis. When IMA and lactate levels were combined, the AUCs were 0.815 (0.762–0.867) and 0.806 (0.754–0.858) for the diagnosis of sepsis and septic shock, respectively. IMA levels independently predicted sepsis (odds ratio, 1.05; 95% CI, 1.00–1.09; P=0.029) and septic shock (odds ratio, 1.07; 95% CI, 1.02–1.11; P=0.002). Conclusion Our findings indicate that IMA levels are a useful biomarker for diagnosing sepsis/ septic shock early, and their combination with lactate levels can enhance the predictive power for early diagnosis of sepsis/septic shock in the ED.

This study investigated the recovery and absorption rates of murine norovirus, a surrogate for human norovirus, by using NanoCeram(R) filters which served as a tool for recovering viruses. In the study, two types of NanoCeram(R) filters were employed: one was a cartridge type and the other was a disc type (phi 47 mm) whose surface area is 75 times smaller than the cartridge type. The analytical method was the real-time reverse transcription-polymerase chain reaction (RT-PCR). The study found that the average recovery rates of the cartridge type and the disc type were 30.9% and 29.5% respectively. Since these two rates were very close to each other, the adsorption rate of the cartridge type could be predicted with the disc type. Analyzing recovery and absorption rates of the disc type based on different filtered volumes showed that when the volume increased from 0.5 L to 20 L, the average recovery rate rose from 14.78% to 30.41 %, while the average absorption rate dropped from 56.33% to 10.48%. The increase in turbidity from less than 1 NTU to less than 3 NTU raised the average recovery rate from 47.23% to 82.84%.
Absorption ; Adsorption ; Humans ; Norovirus