Objective:To explore and summarize the key points and main treatment measures for successfully treating sever Rickettsia japonica infection. Methods:A 69-year-old female with severe Japanese spotted fever was admitted to Yichang Central People’s Hospital on May 15 in 2024 and was successfully treated. The clinical data of the patient were retrospectively analyzed.Results:The patient was quickly progressed to severe pneumonia，septic shock，dry gangrene of the extremities during the treatment process，and hepatic dysfunction，cardiac dysfunction，renal dysfunction and gastrointestinal hemorrhage were observed. After active anti-infection，anti-shock，continuous renal replacement therapy，and symptomatic supportive treatment，the patient’s condition improved，but the dry gangrene of the limbs was irreversible，ultimately leading to amputation.Conclusion:Timely diagnosis，early and active anti infective treatment，and effective management of various complications are the key to successfully treating cases of Ricketttsia Japonica

This tutorial addresses the current lack of standardized protocols for closed reduction and cast immobilization for distal radius fractures in China, along with a high incidence of the complications of these fractures. Based on the 2024 Evidence-Based Guidelines for Diagnosis and Treatment of Adult Distal Radius Fractures, it establishes a standardized operational procedure. Using the classic Colles fracture as an example, it provides a comprehensive and step-by-step explanations of the closed reduction and cast immobilization techniques, including detailed descriptions and schematic illustrations covering patient positioning, measurement, reduction maneuvers, cast fabrication, cast application, molding, and assessment.

This tutorial addresses the current lack of standardized protocols for closed reduction and cast immobilization for distal radius fractures in China, along with a high incidence of the complications of these fractures. Based on the 2024 Evidence-Based Guidelines for Diagnosis and Treatment of Adult Distal Radius Fractures, it establishes a standardized operational procedure. Using the classic Colles fracture as an example, it provides a comprehensive and step-by-step explanations of the closed reduction and cast immobilization techniques, including detailed descriptions and schematic illustrations covering patient positioning, measurement, reduction maneuvers, cast fabrication, cast application, molding, and assessment.

Objective:To explore and summarize the key points and main treatment measures for successfully treating sever Rickettsia japonica infection. Methods:A 69-year-old female with severe Japanese spotted fever was admitted to Yichang Central People’s Hospital on May 15 in 2024 and was successfully treated. The clinical data of the patient were retrospectively analyzed.Results:The patient was quickly progressed to severe pneumonia，septic shock，dry gangrene of the extremities during the treatment process，and hepatic dysfunction，cardiac dysfunction，renal dysfunction and gastrointestinal hemorrhage were observed. After active anti-infection，anti-shock，continuous renal replacement therapy，and symptomatic supportive treatment，the patient’s condition improved，but the dry gangrene of the limbs was irreversible，ultimately leading to amputation.Conclusion:Timely diagnosis，early and active anti infective treatment，and effective management of various complications are the key to successfully treating cases of Ricketttsia Japonica

Objective:To study the role of neutrophil density and molecular mechanism in neutrophils-mediated inflammatory response induced by monosodium urate (MSU) crystals.Methods:Polymorphonuclear neutrophils (PMNs) isolated from healthy human peripheral blood were treated with MSU crystals at different density (5×10 6/ml, 20×10 6/ml, 100×10 6/ml) in vitro. The mean fluorescence intensity (MFI) of PMNs and production of reactive oxygen species (ROS) were detected by flow cytometry. The distribution of MSU crystals was observed by polarized light microscopy. The neutrophil extracellular traps (NETs) formation was detected by immune fluorescence. The cytokines in cell supernatant were measured by beads assay including interleukin 1β (IL-1β) , tumor necrosis factor α (TNFα) , interleukin 8 (IL-8) , interferon inducible protein 10 (IP-10) , macrophage inflammatory protein 1 (MIP-1) , monokine induced by interferon-γ (MIG) , macrophage inflammatory protein 1α (MIP-1α) , macrophage inflammatory protein 1β (MIP-1β) . Results:(1) After MSU crystal intervention, the side scatters (SSC) of neutrophils with medium-cell density (20×10 6/ml) and high-cell density (100×10 6/ml) were 128±13 and 93±9 respectively, both significantly lower than 170±19 in low-cell density (5×10 6/ml) group.(2) Similarly, compared with low-cell density group, the MFI (lucifer yellow) of PMNs with high-cell density was 1.8±0.2, also significantly decreased ( P<0.05). When co-treated with oxygenated adenosine triphosphate (oxATP), MFI of PMNs were all enhanced consistently. (3) In MSU crystals stimulated PMNs, after adding 2′,7′-dichlorodihydrofluorescein diacetate, the MFI values were 0.85±0.32, 2.49±0.78, 4.54±1.02 in low cell density groups, medium cell density groups, and high cell density groups respectively, indicating that the generation of ROS was positively correlated with the increase of PMN density ( P<0.05). After the intervention of oxATP, the ROS production was significantly reduced. (4) MSU crystal induced NETs formation, especially at high cell density. NETs formation promotes MSU crystal aggregation, which could be partially overcome by oxATP pretreatment. (5) The expression of cytokines were all significantly decreased in the supernatant of PMNs at high cell density exposed to MSU crystals compared with PMNs at medium cell density ( P<0.05) . Conclusion:The PMN-mediated inflammation induced by MSU crystals is cell density dependent, and ATP may play a role in partially overcoming the process.