Hyperbaric oxygen treatment in thromboangiitis obliterans: a retrospective clinical audit

Self-assembled polyelectrolyte complexes of chitosan and fucoidan for sustained growth factor release from PRP enhance proliferation and collagen deposition in diabetic mice

Diabetic wound management is a serious health care challenge due to higher rates of relapse, expensive treatment approaches, and poor healing outcomes. Among cell-based therapies, use of platelet-rich plasma (PRP) has been shown to be effective for diabetic wounds, but its poor shelf-life limits its clinical use. Here, we demonstrate a simple but effective polymer system to increase the shelf-life of PRP by developing a polyelectrolyte complex with dropwise addition of chitosan solution containing PRP by simple mixing at room temperature. Thus, prepared chitosan-fucoidan (CF) carrier complex encapsulated more than 95% of the loaded PRP. The resulting CF/PRP colloids were spherical in shape and ensured extended PRP release up to 72 h at 37 °C. Routine characterization (FT-IR, XRD, SEM) showed the material properties. The biological assays showed that CF complexes were biocompatible while CF/PRP enhanced the proliferation of fibroblasts and keratinocytes via higher Ki67 expression and fibroblast migration. Further investigations using a diabetic mouse model demonstrated significantly higher wound contraction and histopathological observations showed increased fibroblast migration, and collagen and cytokeratin deposition in treatment groups. The results are suggestive of the efficacy of CF/PRP as a cost-effective topical formulation for the sustained delivery of growth factors in treating chronic diabetic wounds.

Milestones in thromboangiitis obliterans. A position paper of the VAS-European Independent Foundation in Angiology/Vascular Medicine

BACKGROUND

Unfortunately, even today Thromboangiitis Obliterans has disease features that remain misunderstood or underappreciated. The epidemiology, etiology and pathophysiology of the disease are still unclear. Biomarkers and disease activity markers are lacking, thus clinical assessment is difficult. We are still struggling to establish unique diagnostic, staging and treatment criteria. This is an academic-collaborative effort to describe the pathophysiology, the clinical manifestations, the diagnostic approach, and the challenges of management of patients with TAO.

METHODS

A systematic search for relevant studies dating from 1900 to the end of 2020 was performed on the PubMed, SCOPUS, and Science Direct databases.

RESULTS

Given the intriguing nature of presentation of TAO, its management, to some extent is not only different in different regions of the world but also varies within the same region. Following this project, we discovered ambiguity, overlap and lack of clear-cut criteria for management of TAO.

CONCLUSIONS AND RELEVANCE

An international group of experts however came to one conclusion. They all agree that management of TAO is in need of a call for action for a renewed global look with multi-center studies, to update the geographical distribution of the disease and to establish a unique set of diagnostic criteria and a consensus-based guideline for best treatment based on current evidence.

miR-100 alleviates the inflammatory damage and apoptosis of H2O2-induced human umbilical vein endothelial cells via inactivation of Notch signaling by targeting MMP9

OBJECTIVE

Thromboangiitis obliterans is a nonatherosclerotic segmental inflammatory disease, and miR-100 plays an anti-inflammatory role in chronic inflammation. Therefore, we hypothesized that miR-100 might alleviate the inflammatory damage and apoptosis of H₂O₂-induced ECV304 cells and aimed to investigate the relationship between miR-100 and thromboangiitis obliterans and the related molecular mechanism.

METHODS

Cell counting kit-8 was used to detect cell viability, and the expression of inflammatory factors and oxidative stress was measured by ELISA. TUNEL assay was used to detect the apoptosis of human umbilical vein endothelial cells after induction by H₂O₂. Furthermore, the interaction between miR-100 and matrix metalloproteinase-9 was verified by dual-luciferase assay. Quantitative reverse transcription polymerase chain reaction and western blot were used to detect the expression of the adhesion factors, apoptosis-related proteins and Notch pathway-related protein.

RESULTS

The results revealed that miR-100 was decreased in H₂O₂-induced human umbilical vein endothelial cells. Overexpression of miR-100 attenuated inflammatory response and cell apoptosis in H₂O₂-induced human umbilical vein endothelial cells. The overexpression of miR-100 inhibited matrix metalloproteinase-9 expression in H₂O₂-induced human umbilical vein endothelial cells. miR-100 inhibited H₂O₂-induced human umbilical vein endothelial cell inflammation, oxidative stress, and cell apoptosis via inactivation of Notch signaling by targeting matrix metalloproteinase.

CONCLUSIONS

Our study demonstrated that miR-100 reduced the inflammatory damage and apoptosis of H₂O₂-induced human umbilical vein endothelial cells via inactivation of Notch signaling by targeting matrix metalloproteinase. These findings suggested that miR-100 might be a novel therapeutic target for the prevention of thromboangiitis obliterans.

Risk Factors, Mechanisms and Treatments of Thromboangiitis Obliterans: An Overview of Recent Research

BACKGROUND

Thromboangiitis obliterans (TAO) is a nonatherosclerotic thromboticocclusive vasculitis that affects the vessels of the small and medium-sized extremities. No explicit etiology or pathogenesis of TAO has been proven, and more effective treatments are needed.

OBJECTIVE

The study aimed to summarize and present an overview of recent advances regarding the risk factors, mechanisms and treatments of TAO and to organize the related information in figures to provide a comparatively complete reference.

METHODS

We searched PubMed for English-language literature about TAO without article type limits, including articles about the risk factors, pathological mechanisms and treatments of TAO in the last 10 years with essential supplements (references over ranges and English abstracts of Russian literature).

RESULTS

After screening content of works of literature, 99 references were evaluated. We found that risk factors of TAO include smoking, gene factors and periodontal diseases. The underlying mechanism of TAO involves oxidative stress, immunity, hemodynamic changes, inflammation and so on. Moreover, similarities in genetic factors and cigarette relevance existed between periodontal diseases and TAO, so further study of relationship was required. For TAO treatment, medicine, endovascular intervention and revascularization surgery, autologous cell therapy and novel therapies were also mentioned. Besides, a hypothesis that infection triggers autoimmunity in TAO could be speculated, in which TLR4 plays a key role.

CONCLUSION

1. A hypothesis is put forward that infections can trigger autoimmunity in TAO development, in which TLR4, as a key agent, can activate immune signaling pathways and induce autoimmune cytokines expression. 2. It is suggested to reconsider the association between periodontal diseases and TAO, as they share the same high-risk population. Controlling periodontal disease severity in TAO studies may provide new clues. 3. For TAO treatment, endovascular intervention and autologous cell therapy both showed promising long-term therapeutic effectiveness, in which autologous cell therapy is becoming more popular, although more clinical comparisons are needed.

Emerging indications for hyperbaric oxygen

PURPOSE OF REVIEW

To identify and discuss emerging trends in the therapeutic use of hyperbaric oxygen.

RECENT FINDINGS

There has been a maturing of the clinical evidence to support the treatment of sudden hearing loss, a wide range of problematic chronic wound states and the prevention and treatment of end-organ damage associated with diabetes mellitus. On the other hand, the controversy continues concerning the use of hyperbaric oxygen therapy (HBOT) to treat sequelae of mild traumatic brain injury. HBOT remains poorly understood by many medical practitioners despite more than 50 years of clinical practice. Pharmacological actions arise from increased pressures of oxygen in the blood and tissues. Most therapeutic mechanisms identified are not the simple result of the reoxygenation of hypoxic tissue, but specific effects on immunological and metabolic pathways by this highly reactive element. HBOT remains controversial despite biological plausibility and a solid clinical evidence base in several disease states.

SUMMARY

Multiple proposals for new indications for HBOT continue to emerge. Although many of these will likely prove of limited clinical importance, some show significant promise. Responsible practitioners remain acutely aware of the need for high-quality clinical evidence before introducing emerging indications into routine practice.