The Bidirectional Interactions Between Inflammation and Coagulation in Fracture Hematoma

Association between high-sensitivity C-reactive protein and bleeding in dual antiplatelet therapy age: a retrospective observational study

OBJECTIVES

The aim of the present study was to investigate the association of high-sensitivity C-reactive protein (hs-CRP) with bleeding events among patients with acute coronary syndrome (ACS) received dual antiplatelet therapy (DAPT) after percutaneous coronary intervention.

DESIGN

An observational and multicentre study was conducted among non-ST-segment elevation ACS (NSTE-ACS).

SETTING

The study was conducted at five medical centres in China.

PARTICIPANTS

This study retrospectively included 2583 adults with NSTE-ACS between 1 January 2010 and 31 December 2014.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcome was major bleeding, defined by the Bleeding Academic Research Consortium definition (grades 3-5). The second outcome was death and any bleeding.

RESULTS

53 (2.1%) patients experienced major bleeding in the hospital. Patients with hs-CRP levels greater than 8.20 mg/L had the highest incidence of in-hospital major bleeding (25 (3.9%), p<0.001) compared with the other groups. Multivariable analysis indicated that hs-CRP was an independent factor associated with in-hospital major bleeding (continuous: adjusted OR=1.01, 95% CI: 1.01 to 1.02, p<0.001; quartiles: adjusted OR for quartile 4 (referring to quartile 1) =3.71, 95% CI: 1.35~10.23, p=0.011), which was further confirmed by subgroup analysis and receiver operating characteristic curves. The restricted cubic spline analysis demonstrated an S-shaped association between hs-CRP and major bleeding. During the 5-year follow-up, there was a significantly high risk of bleeding in patients with higher hs-CRP levels.

CONCLUSIONS

Systemic inflammation marker hs-CRP in patients with NSTE-ACS who received DAPT is associated with a high risk of in-hospital major bleeding. An S-shaped association was found between hs-CRP and bleeding events. Further studies are warranted to optimise antithrombotic drug therapy in high bleeding risk patients during follow-up.

Comprehensive Overview of Interface Strategies in Implant Osseointegration

With the improvement of implant design and the expansion of application scenarios, orthopedic implants have become a common surgical option for treating fractures and end‐stage osteoarthritis. Their common goal is rapidly forming and long‐term stable osseointegration. However, this fixation effect is limited by implant surface characteristics and peri‐implant bone tissue activity. Therefore, this review summarizes the strategies of interface engineering (osteogenic peptides, growth factors, and metal ions) and treatment methods (porous nanotubes, hydrogel embedding, and other load‐release systems) through research on its biological mechanism, paving the way to achieve the adaptation of both and coordination between different strategies. With the transition of the osseointegration stage, interface engineering strategies have demonstrated varying therapeutic effects. Especially, the activity of osteoblasts runs almost through the entire process of osseointegration, and their physiological activities play a dominant role in bone formation. Furthermore, diseases impacting bone metabolism exacerbate the difficulty of achieving osseointegration. This review aims to assist future research on osseointegration engineering strategies to improve implant‐bone fixation, promote fracture healing, and enhance post‐implantation recovery.

Diagnostic value of tissue plasminogen activator-inhibitor complex in sepsis-induced liver injury: A single-center retrospective case-control study

BACKGROUND

Sepsis often causes severe liver injury and leads to poor patient outcomes. Early detection of sepsis-induced liver injury (SILI) and early treatment are key to improving outcomes.

AIM

To investigate the clinical characteristics of SILI patients and analyze the associated risk factors, to identify potential sensitive biomarkers.

METHODS

Retrospective analysis of clinical data from 546 patients with sepsis treated in the intensive care unit of the 908th Hospital of Chinese People's Liberation Army Joint Logistic Support Force between May 2018 and December 2022. The patients were divided into the sepsis group (n = 373) and SILI group (n = 173) based on the presence of acute liver injury within 2 hours of admission. We used the random forest algorithm to analyze risk factors and assessed potential diagnostic markers of SILI using the area under the receiver operating characteristic curve, Kaplan-Meier survival curves, subgroup analysis and correlation analysis.

RESULTS

Compared with the sepsis group, tissue plasminogen activator-inhibitor complex (t-PAIC) levels in serum were significantly higher in the SILI group (P < 0.05). Random forest results showed that t-PAIC was an independent risk factor for SILI, with an area under the receiver operating characteristic curve of 0.862 (95% confidence interval: 0.832-0.892). Based on the optimal cut-off value of 11.9 ng/mL, patients at or above this threshold had significantly higher levels of lactate and Acute Physiology and Chronic Health Evaluation II score. The survival rate of these patients was also significantly worse (hazard ratio = 2.2, 95% confidence interval: 1.584-3.119, P < 0.001). Spearman's correlation coefficients were 0.42 between t-PAIC and lactate, and 0.41 between t-PAIC and aspartate transaminase. Subgroup analysis showed significant differences in t-PAIC levels between patients with different severity of liver dysfunction.

CONCLUSION

T-PAIC can serve as a diagnostic indicator for SILI, with its elevation correlated with the severity of SILI.

Delayed admission to hospital with proper prehospital treatments prevents severely burned patients from sepsis in China: A retrospective study

BACKGROUND

Sepsis is one of the major causes of morbidity and mortality in burn patients. However, the optimal timing of admission which can minimize the probability of sepsis is still unclear. This study aims to determine the optimal time period of admission for severely burned patients and find out the possible reasons for it.

METHOD

185 victims to the Kunshan factory aluminum dust explosion accident, which happened on August 2nd, 2014, were studied. The optimal cutpoint for continuous variables in survival models was determined by means of the maximally selected rank statistic. Univariate and multivariate analyses were further conducted to verify that admission time was not a risk factor for sepsis. Subgroup analyses were performed to find out possible contributing factors for the result.

RESULT

The cutoff point for admission time was determined as seven hours, which was supported by the survival curve (p < 0.001). Multivariate analysis showed that, in our study population, delayed admission time was not a risk factor for sepsis (HR = 0.610, 95 %CI = 0.415 - 0.896, p = 0.012). Subgroup analyses showed that "Tracheotomy before admission" (p = 0.002), "Whole blood transfusion" (p < 0.001), "Hemodynamic instability before admission" (p = 0.02), "Has a burn department in the hospital" (p = 0.009), "Has a burn ICU in the hospital" (p < 0.001), "Acute heart failure (AHF)" (p = 0.05), "acute respiratory distress syndrome (ARDS)" (p = 0.05) and "GI bleeding" (p = 0.04) were all statistically significant.

CONCLUSION

In our study population, we found that delayed admission time was not a risk factor associated with a reduced incidence of sepsis among severely burned patients. This might be attributed to variations in prehospital treatments (whole blood transfusion and tracheotomy), whether the hospital had a burn department/ICU, and certain complications (AHF, ARDS and GI bleeding). It can be inferred that early prehospital care plays a crucial role in reducing sepsis risk among severe burn patients.

Mechanism and therapeutic potential of traditional Chinese medicine extracts in sepsis

Sepsis is a complex syndrome characterized by multi-organ dysfunction, due to the presence of harmful microorganisms in blood which could cause mortality. Complications associated with sepsis involve multiple organ dysfunction. The pathogenesis of sepsis remains intricate, with limited treatment options and high mortality rates. Traditional Chinese medicine (TCM) has consistently demonstrated to have a potential on various disease management. Its complements include reduction of oxidative stress, inhibiting inflammatory pathways, regulating immune responses, and improving microcirculation. Traditional Chinese medicine can mitigate or even treat sepsis in a human system. This review examines progress on the use of TCM extracts for treating sepsis through different pharmacological action and its mechanisms. The potential targets of TCM extracts and active ingredients for the treatment of sepsis and its complications have been elucidated through molecular biology research, network pharmacology prediction, molecular docking analysis, and visualization analysis. Our aim is to provide a theoretical basis and empirical support for utilizing TCM in the treatment of sepsis and its complications while also serving as a reference for future research and development of sepsis drugs.

Research Progress on Natural Small-Molecule Compounds for the Prevention and Treatment of Sepsis

Sepsis is a serious disease with high mortality and has been a hot research topic in medical research in recent years. With the continuous reporting of in-depth research on the pathological mechanisms of sepsis, various compounds have been developed to prevent and treat sepsis. Natural small-molecule compounds play vital roles in the prevention and treatment of sepsis; for example, compounds such as resveratrol, emodin, salidroside, ginsenoside, and others can modulate signaling through the NF-κB, STAT3, STAT1, PI3K, and other pathways to relieve the inflammatory response, immunosuppression, and organ failure caused by sepsis. Here, we discuss the functions and mechanisms of natural small-molecule compounds in preventing and treating sepsis. This review will lay the theoretical foundation for discovering new natural small-molecule compounds that can potentially prevent and treat sepsis.

The Effects of Indobufen on Micro-Inflammation and Peritoneal Transport Function in Patients Undergoing Continuous Ambulate Peritoneal Dialysis: A Prospective Randomized Controlled Study

Indobufen possesses anticoagulant and antithrombotic effects that can improve micro-inflammation and renal function. This study aimed to examine whether indobufen could improve the microinflammatory state in patients on continuous ambulatory peritoneal dialysis (CAPD) and explore its therapeutic effects on peritoneal transport function. A total of 60 patients undergoing CAPD from October 2019 to October 2020 were selected and randomized to the control and indobufen groups. All patients received conventional treatments. Blood routine and the serum and peritoneal effusion levels of tumor necrosis factor-α (TNF-α), transforming growth factor-β1 (TGF-β1), cellular fibronectin (cFN), and vascular endothelial growth factor were determined before and after 6 months of treatment. The peritoneal equilibrium test (PET) was used to evaluate peritoneal transport function. There were no significant differences in PET results, microinflammatory state, and biochemical indices between the two groups before treatment (P > 0.05). After 6 months of treatment, platelet-to-lymphocyte ratio and serum and peritoneal effusion TNF-α levels in the indobufen group were decreased compared with the control group (P < 0.05). Serum and peritoneal effusion TGF-β1 and cFN levels in the indobufen group were reduced compared with the control group (P < 0.05). PET results in the indobufen group were decreased compared with baseline (P < 0.05). The difference in PET results between the two groups before and after treatment was statistically significant (P < 0.05). Indobufen could improve the peritoneal transport function in patients undergoing CAPD. The underlying mechanism might be related to the improvement of the microinflammatory state and peritoneal fibrosis. SIGNIFICANCE STATEMENT: Microinflammation and peritoneal fibrosis can lead to peritoneal failure in CAPD. Indobufen is a novel antiplatelet drug that can alleviate renal fibrosis and improve renal function in patients with diabetic nephropathy. Indobufen can improve the peritoneal transport function in patients undergoing CAPD. The mechanism of indobufen improving the peritoneal function might be related to the improvement of the microinflammatory state and peritoneal fibrosis.

Association between high-sensitivity C-reactive protein and bleeding in non-ST-segment elevation acute coronary syndrome: A multicentre cohort of Chinese population.. [DOI: 10.21203/rs.3.rs-2241865/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Background The association between high-sensitivity C-reactive protein (hs-CRP) and bleeding risk in acute coronary syndrome (ACS) patients remains unclear. This study aimed to examine the association between bleeding events and different hs-CRP levels in patients with non-ST elevation ACS (NSTE-ACS). Methods This study retrospectively included 2583 adults with NSTE-ACS between January 1, 2010, and December 31, 2014, at 5 medical centres in China. The primary outcome was major bleeding, defined by the Bleeding Academic Research Consortium definition (grades 3–5). Results Fifty-three (2.1%) patients experienced major bleeding in the hospital. Patients with hs-CRP levels greater than 8.20 mg/L had the highest incidence of in-hospital major bleeding (25 (3.9%), P < 0.001) compared with the other groups. Multivariable analysis indicated that hs-CRP was an independent factor associated with in-hospital major bleeding (continuous: adjusted OR = 1.01, 95% CI: 1.01–1.02, P < 0.001; quartiles: adjusted OR for quartile 4 (referring to quartile 1) = 3.71, 95% CI: 1.35 ~ 10.23, P = 0.011), which was further confirmed by subgroup analysis and receiver operating characteristic curves. The restricted cubic spline analysis demonstrated an S-shaped association between hs-CRP and major bleeding. During the 5-year follow-up, there was a significantly high risk of bleeding in patients with higher hs-CRP levels. Conclusion Higher hs-CRP level at admission in NSTE-ACS patients is associated with high risk of in-hospital major bleeding. An S-shaped association was found between hs-CRP and bleeding events. Further studies are warranted to optimize antithrombotic drug therapy in high-bleeding risk patients during follow-up.

MicroRNA-451a and Th1/Th2 ratio inform inflammation, septic organ injury, and mortality risk in sepsis patients

Aims

MicroRNA-451a (miR-451a) regulates Th1/Th2 cell differentiation, inflammation, and septic organ injury in several experiments. Therefore, the present study aimed to explore the inter-correlation of miR-451a with the Th1/Th2 ratio, and their association with inflammation, septic organ injury, and mortality risk in patients with sepsis.

Methods

Consecutively, 117 patients with sepsis and 50 healthy controls (HCs) were enrolled. Peripheral blood mononuclear cell samples were collected to detect miR-451a expression and the Th1/Th2 ratio in all subjects.

Results

MiR-451a (p < 0.001), Th1 cells (p = 0.014), and the Th1/Th2 ratio (p < 0.001) increased, while Th2 cells (p < 0.001) declined in patients with sepsis compared with HCs. It was of note that miR-451a was positively correlated with Th1 cells (p = 0.002) and the Th1/Th2 ratio (p = 0.001), while it was negatively related to Th2 cells (p = 0.005) in patients with sepsis. Meanwhile, miR-451a and the Th1/Th2 ratio correlated with most of the following indexes: TNF-α, IL-1β, IL-6, C-reactive protein, sequential organ failure assessment (SOFA) score, or Acute Physiology and Chronic Health Evaluation II (APACHE II) score (most p < 0.05). Moreover, miR-451a (p < 0.001) and the Th1/Th2 ratio (p = 0.001) increased in deaths compared to survivors of sepsis; further ROC curve showed both miR-451a and the Th1/Th2 ratio possessed a certain value to predict mortality of patients with sepsis. Additionally, the Th1/Th2 ratio [odds ratio (OR): 2.052, p = 0.005] was independently related to 28-day mortality risk from multivariate logistic regression.

Conclusion

MiR-451a correlates with the Th1/Th2 ratio, and they both relate to inflammation, septic organ injury, and mortality risk in patients with sepsis.

Biological activities and phenolic compounds of olive oil mill wastewater from Abani, endemic Algerian variety

The current study aimed to determination of cytotoxicity, antioxidant, anti-inflammatory, anti-hemolytic, and anticoagulant activities of phenolic compounds extracted from olive oil mill wastewater (OMW) issue from the cold extraction of olive oil from Khenchela eastern in Algeria. The LC–MS (liquid chromatography–mass spectrometry) results were revealed the presence of 20 phenolic compounds in the extract of OMW and mostly consisted of Kaempferol, 4,5-di-O-caffeoyquinic acid, quinic acid, and caffeic acid. The extracts possessed effective reducing power (FRAP) and high radical scavenging activity against DPPH (2,2-diphenyl-1-picrylhydrazyl), ABTS + (2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) free radicals, and it inhibited cytochrome c reduction in a dose-dependent manner. They exert a protective effect on red blood cells, and they were found to exhibit the highest inhibitory effect anti-inflammatory activity using inhibition of protein denaturation (IPD) and membrane stabilizing potential (MSP) tests (80.46 ± 3.81 µg/mL and 87.43 ± 0.66 µg/mL) more than the standard used. The extract also showed the greatest anticoagulant activity in both the endogenous and exogenous routes (44.77 ± 0.25 s and 15.84 ± 0.12 s, respectively). Based on these findings, it is reasonable to infer that OMW is a good source of natural phenolic compounds with potential antioxidant, anti-inflammatory, and anticoagulant properties.

Preoperative incidence and risk factors of deep vein thrombosis in patients with an isolated patellar fracture

Purpose

This study aimed to investigate the incidence, location, and related factors of preoperative deep venous thrombosis (DVT) in patients with isolated patellar fractures.

Methods

Patients with an isolated patellar fracture, admitted between January 2013 and December 2019 at our institution, were retrospectively analyzed. Upon admission, patients underwent routine Doppler ultrasound scanning (DUS) of the bilateral lower extremities to detect DVT; those with DVT were assigned to the case group and those without DVT to the control group. Patients in both groups did not perform preoperative off-bed weight-bearing exercises. Data on demographics, comorbidities, and laboratory test results upon admission were extracted. Variables were evaluated between the two groups using univariate analyses, and independent risk factors associated with DVT were identified by logistic regression analysis.

Results

During the study period, 827 patients were included, of whom 5.8% (48/827) were found to have preoperative DVT. In DVT patients, 85.4%(41/48) were injured, 8.3%(4/48) were not injured, and 6.3%(3/48) were lower limbs. Multivariate analysis showed that male (male vs. female, odds ratio, OR = 2.25), delayed from injury to DUS (in each day, OR = 1.29), and elevated plasma D-dimer level (> 0.5 µg/mL, OR = 2.47) were independent risk factors associated with DVT.

Conclusions

Despite the low prevalence of DVT after an isolated patellar fracture, this study underscores the importance of identifying those with a high risk of DVT, especially those with multiple identifiable factors, and encourage the early targeted use of anti-thromboembolic agents to reduce DVT occurrence.

Postoperative Fluid Collections in Total Joint Arthroplasty: A Narrative Review

A post-operative fluid collection (POFC) represents a common finding in both primary and revision total joint arthroplasty (TJA). Fortunately, most resolve on their own, but in instances where they become symptomatic, prompt identification and management are paramount, especially when they occur adjacent to a joint arthroplasty because of the increased the risk of developing a periprosthetic joint infection. A strong clinical suspicion with appropriate clinical exam is required along with select imaging modalities to arrive at a diagnosis. Meticulous surgical technique is crucial to prevent POFC, but new emerging treatments continue to evolve. This article presents an updated overview of incidence, pathophysiology, diagnosis, and management of POFC in the setting of TJA. We review the role of select imaging modalities as well as summarize current literature regarding new treatments such as sclerotherapy agents, acellular dermal matrices, and negative pressure wound therapy. Future studies are necessary to explore the interplay of inflammatory mediators in POFC formation and to define their role in fluid collection resolution.

OGDH is involved in sepsis induced acute lung injury through the MAPK pathway

Background

Acute lung injury (ALI) induced by sepsis is a common cause of death in clinical practice, and there remains a lack of clinical effective treatment. Cecal ligation and puncture (CLP) is a classic animal model of sepsis, which can induce ALI. Studies have shown that in the lung injury cell model, OGDH (oxoglutarate dehydrogenase) transcription is up-regulated, which is a potential therapeutic target for acute pneumonia. The purpose of this study was to confirm the effects of OGDH on lung injury and inflammation in animal and cell models, and to explore its mechanism.

Methods

By analyzing the GSE16650 gene set, the upregulated OGDH gene was detected in the lung injury cell model. In a sepsis animal model established by CLP and a lung injury cell model, RT-PCR, immunohistochemistry, WB, and other techniques were used to verify the upregulation of OGDH expression, which was then was down-regulated with shRNA to confirm its relationship with ALI. Further, ELISA, RT-PCR, and WB were used to detect the effect of OGDH on the expression of pro-inflammatory factors including IL-1β, IL-6, IL-18, and TNF-α. The downstream pathway of OGDH was predicted using KEGG and GSEA tools and verified by WB and immunofluorescence.

Results

The results showed OGDH was highly expressed in a lung injury cell model and the lung tissue of ALI mice induced by CLP, and downregulation of OGDH alleviated sepsis induced ALI. In animal models and cell models, the expression of OGDH was positively correlated with the expression of pro-inflammatory factors. OGDH may act through the MAPK pathway.

Conclusions

Under the pathological condition of sepsis, OGDH amplifies the inflammatory response through the MAPK pathway, releases pro-inflammatory factors, and induces ALI.

Protein adsorption/desorption dynamics on Ca-enriched titanium surfaces: biological implications

Calcium ions are used in the development of biomaterials for the promotion of coagulation, bone regeneration, and implant osseointegration. Upon implantation, the time-dependent release of calcium ions from titanium implant surfaces modifies the physicochemical characteristics at the implant-tissue interface and thus, the biological responses. The aim of this study is to examine how the dynamics of protein adsorption on these surfaces change over time. Titanium discs with and without Ca were incubated with human serum for 2 min, 180 min, and 960 min. The layer of proteins attached to the surface was characterised using nLC-MS/MS. The adsorption kinetics was different between materials, revealing an increased adsorption of proteins associated with coagulation and immune responses prior to Ca release. Implant-blood contact experiments confirmed the strong coagulatory effect for Ca surfaces. We employed primary human alveolar osteoblasts and THP-1 monocytes to study the osteogenic and inflammatory responses. In agreement with the proteomic results, Ca-enriched surfaces showed a significant initial inflammation that disappeared once the calcium was released. The distinct protein adsorption/desorption dynamics found in this work demonstrated to be useful to explain the differential biological responses between the titanium and Ca-ion modified implant surfaces.

Surface engineering of titania nanotubes incorporated with double-layered extracellular vesicles to modulate inflammation and osteogenesis

Titania nanotubes (TNT) generated on titanium implant are emerged as important modification technique to facilitate bone regeneration. Mesenchymal stem cells (MSCs)-derived exosomes are membrane bound extracellular vesicles (EVs), which play an important role in tissue regeneration. The objective of this study was to generate an EVs hybrid TNT aiming at regulating inflammation, MSCs recruitment and osteogenesis. We isolated EVs from MSCs (MSCs EVs) and 3-day osteogenically differentiated MSCs (3d EVs). MSC EVs and 3d EVs exhibited round morphology under TEM, which also showed robust internalization by human bone marrow derived MSCs (hBMSCs). Next, we fabricated 3d EVs/MSC EVs hybrid TNT. When inflammatory macrophages were co-cultured with EVs hybrid TNT, the gene and protein expression of inflammatory cytokine were significantly reduced. Macrophage morphology was also examined by confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). Further migratory ability study using hBMSCs indicated significant enhancement of MSCs migration in EVs hybrid TNT. In addition, we further demonstrated significant increase of osteogenic differentiation of hBMSCs in EVs hybrid TNT. This study suggests that EVs hybrid TNT may serve as a viable therapeutic approach to enhance osteogenesis and bone regeneration.

Bone marrow aspirate clot: A feasible orthobiologic

Musculoskeletal disorders are one of the major health burdens and a leading source of disability worldwide, affecting both juvenile and elderly populations either as a consequence of ageing or extrinsic factors such as physical injuries. This condition often involves a group of locomotor structures such as the bones, joints and muscles and may therefore cause significant economic and emotional impact. Some pharmacological and non-pharmacological treatments have been considered as potential solutions, however, these alternatives have provided quite limited efficacy due to the short-term effect on pain management and inability to restore damaged tissue. The emergence of novel therapeutic alternatives such as the application of orthobiologics, particularly bone marrow aspirate (BMA) clot, have bestowed medical experts with considerable optimism as evidenced by the significant results found in numerous studies addressed in this manuscript. Although other products have been proposed for the treatment of musculoskeletal injuries, the peculiar interest in BMA, fibrin clot and associated fibrinolytic mechanisms continues to expand. BMA is a rich source of various cellular and molecular components which have demonstrated positive effects on tissue regeneration in many in vitro and in vivo models of musculoskeletal injuries. In addition to being able to undergo self-renewal and differentiation, the hematopoietic and mesenchymal stem cells present in this orthobiologic elicit key immunomodulatory and paracrine roles in inflammatory responses in tissue injury and drive the coagulation cascade towards tissue repair via different mechanisms. Although promising, these complex regenerative mechanisms have not yet been fully elucidated.

Use of in vitro bone models to screen for altered bone metabolism, osteopathies, and fracture healing: challenges of complex models

Approx. every third hospitalized patient in Europe suffers from musculoskeletal injuries or diseases. Up to 20% of these patients need costly surgical revisions after delayed or impaired fracture healing. Reasons for this are the severity of the trauma, individual factors, e.g, the patients’ age, individual lifestyle, chronic diseases, medication, and, over 70 diseases that negatively affect the bone quality. To investigate the various disease constellations and/or develop new treatment strategies, many in vivo, ex vivo, and in vitro models can be applied. Analyzing these various models more closely, it is obvious that many of them have limits and/or restrictions. Undoubtedly, in vivo models most completely represent the biological situation. Besides possible species-specific differences, ethical concerns may question the use of in vivo models especially for large screening approaches. Challenging whether ex vivo or in vitro bone models can be used as an adequate replacement for such screenings, we here summarize the advantages and challenges of frequently used ex vivo and in vitro bone models to study disturbed bone metabolism and fracture healing. Using own examples, we discuss the common challenge of cell-specific normalization of data obtained from more complex in vitro models as one example of the analytical limits which lower the full potential of these complex model systems.

Osteoimmune Modulation and Guided Osteogenesis Promoted by Barrier Membranes Incorporated with S-Nitrosoglutathione (GSNO) and Mesenchymal Stem Cell-Derived Exosomes

Background

The use of polycaprolactone (PCL) for bone defects in a clinical setting is limited due to a lack of bioactivity. Exosomes derived from mesenchymal stem cells (MSCs) have an important immunoregulatory potential and together with S-nitrosoglutathione (GSNO) they possess therapeutic potential for bone regeneration.

Materials and Methods

In this study, PCL was modified with GSNO and MSC-derived exosomes and the impact on macrophages and osteogenes is evaluated.

Results

MSC-derived exosomes exhibited a cup-shaped morphology and were internalized by macrophages and human bone marrow-derived mesenchymal stromal cells (hBMSCs). The pattern of internalization of scaffold-immobilized exosomes was similar in RAW264.7 cells and hBMSCs after 4h and 24h of co-culture. Assessment of macrophage morphology under inflammatory conditions by scanning electronic microscopy (SEM) and confocal microscopy demonstrated macrophages were significantly elongated and expression of pro-inflammatory genes markedly decreased when co-cultured with PCL/PDA + GSNO + exosome scaffolds. Furthermore, this scaffold modification significantly enhanced osteogenic differentiation of hBMSCs.

Discussion

This study demonstrated the possibility of using a GSNO- and exosome-based strategy to adapt barrier membrane scaffolds. PCL/PDA + GSNO + exosome scaffolds may serve as an important barrier membrane for osteogenesis and tissue regeneration.

The Pathogenesis of Sepsis and Potential Therapeutic Targets

Sepsis is defined as “a life-threatening organ dysfunction caused by a host’s dysfunctional response to infection”. Although the treatment of sepsis has developed rapidly in the past few years, sepsis incidence and mortality in clinical treatment is still climbing. Moreover, because of the diverse manifestations of sepsis, clinicians continue to face severe challenges in the diagnosis, treatment, and management of patients with sepsis. Here, we review the recent development in our understanding regarding the cellular pathogenesis and the target of clinical diagnosis of sepsis, with the goal of enhancing the current understanding of sepsis. The present state of research on targeted therapeutic drugs is also elaborated upon to provide information for the treatment of sepsis.