Decontaminative Properties of Cold Atmospheric Plasma Treatment on Collagen Membranes Used for Guided Bone Regeneration

Background cold atmospheric plasma (CAP) is known to be a surface-friendly yet antimicrobial and activating process for surfaces such as titanium. The aim of the present study was to describe the decontaminating effects of CAP on contaminated collagen membranes and their influence on the properties of this biomaterial in vitro. Material and Methods: A total of n = 18 Bio-Gide^® (Geistlich Biomaterials, Baden-Baden, Germany) membranes were examined. The intervention group was divided as follows: n = 6 membranes were treated for one minute, and n = 6 membranes were treated for five minutes with CAP using kINPen^® MED (neoplas tools GmbH, Greifswald, Germany) with an output of 5 W, respectively. A non-CAP-treated group (n = 6) served as the control. The topographic alterations were evaluated via X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). Afterward, the samples were contaminated with E. faecalis for 6 days, and colony-forming unit (CFU) counts and additional SEM analyses were performed. The CFUs increased with CAP treatment time in our analyses, but SEM showed that the surface of the membranes was essentially free from bacteria. However, the deeper layers showed remaining microbial conglomerates. Furthermore, we showed, via XPS analysis, that increasing the CAP time significantly enhances the carbon (carbonyl group) concentration, which also correlates negatively with the decontaminating effects of CAP. Conclusions: Reactive carbonyl groups offer a potential mechanism for inhibiting the growth of E. faecalis on collagen membranes after cold atmospheric plasma treatment.

[Patient safety in differentiated (in-hospital) activation of the resuscitation room for severely injured patients]

BACKGROUND AND OBJECTIVE

Providing trauma services demands high personnel resources and structural costs. The goal of this study was to show if the assignment of trauma patients to a defined A or B resuscitation room treatment as a modified management concept is safe and feasible.

MATERIAL AND METHODS

Between May 2020 and January 2021, all resuscitation room trauma patients were included in this single center prospective observational study. All patients admitted to the resuscitation room underwent a classification according to the German S3 guidelines grade of recommendation GoR A and GoR B in polytrauma and the status of the ABCDE sequence to an A and B resuscitation room. The classification was performed by the senior consultant on call via telephone after consultation and discussion of clinical findings.

RESULTS

All 135 resuscitation room patients were included in the study of whom 42 trauma patients were assigned to the A resuscitation room (A-SR) and 93 were assigned to the B resuscitation room (B-SR). The comparison of the two groups showed that patients in the A‑SR group are more likely to be accompanied by a prehospital emergency physician (80.5%) than patients in the B‑SR group (55.5%). Patients in the B‑SR group showed a significantly higher Glasgow coma scale (GCS). Using the eFAST emergency ultrasound protocol, 2.4% of the A‑SR and 4.3% of the B‑SR patients had trauma-associated pathologies, 26% of the A‑SR and only 3.2% of the B‑SR patients had to be admitted to the ICU, 21.4% of the A‑SR and 1% of the B‑SR patients died within 30 days after trauma. The injury severity scores (ISS) of the A‑SR patients were significantly higher than in the B‑SR group (ISS 28.3 vs. 6.8).

CONCLUSION

The study confirmed that the assignment by the emergency department consultant according to the German S3 guideline in combination with the ABCDE sequence into resuscitation room A or B treatment is feasible, does not compromise the quality of care and is efficient in the use of the personnel resources.

Murine Macrophages Modulate Their Inflammatory Profile in Response to Gas Plasma-Inactivated Pancreatic Cancer Cells

Macrophages and immuno-modulation play a dominant role in the pathology of pancreatic cancer. Gas plasma is a technology recently suggested to demonstrate anticancer efficacy. To this end, two murine cell lines were employed to analyze the inflammatory consequences of plasma-treated pancreatic cancer cells (PDA) on macrophages using the kINPen plasma jet. Plasma treatment decreased the metabolic activity, viability, and migratory activity in an ROS- and treatment time-dependent manner in PDA cells in vitro. These results were confirmed in pancreatic tumors grown on chicken embryos in the TUM-CAM model (in ovo). PDA cells promote tumor-supporting M2 macrophage polarization and cluster formation. Plasma treatment of PDA cells abrogated this cluster formation with a mixed M1/M2 phenotype observed in such co-cultured macrophages. Multiplex chemokine and cytokine quantification showed a marked decrease of the neutrophil chemoattractant CXCL1, IL6, and the tumor growth supporting TGFβ and VEGF in plasma-treated compared to untreated co-culture settings. At the same time, macrophage-attractant CCL4 and MCP1 release were profoundly enhanced. These cellular and secretome data suggest that the plasma-inactivated PDA6606 cells modulate the inflammatory profile of murine RAW 264.7 macrophages favorably, which may support plasma cancer therapy.

A case of giant retroperitoneal lymphangioma and IgG4-positive fibrosis: Causality or coincidence?

Several chronic inflammatory diseases have been found to be a subtype of IgG4-related disease, all of which have a typical clinical and histological change, which is based in particular on an overexpression of IgG4 and subsequent fibrosis. At least a part of the retroperitoneal fibrosis, which was originally classified as idiopathic, seems to be assigned to IgG4-related disease. Lymphangiomas are benign, cystic tumors that rarely occur in adults. However, there is no firm association with IgG4-related disease described in the literature to date. This report is about a patient suffering from acute renal failure due to a giant retroperitoneal cyst. Surgical resection remains incomplete in the iliac vessel area due to severe fibrosis and histology revealed features of both lymphangioma and IgG4⁺ fibrosis. The case description is followed by a brief overview of IgG4-related disease and a consideration of whether lymphangiomas might be assigned to this topic.

Castleman's disease mimicked melanoma metastasis in the mesentery - A case report

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Castleman’s disease (CD) is a rare finding and diagnosis is very challenging.

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Intraabdominal localization is uncommon and can pretend malignancy.

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Misinterpretation might lead to surgical overtreatment of asymptomatic patients.

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Close follow-up examination might help to distinguish between malignancy and CD.

Introduction

Castleman’s disease (CD) is a rare and mainly asymptomatic cause of lymph node swelling. Often it is unicentric and located in the mediastinum. Due to rarity of the disease as well as a lack of symptoms, diagnosis proves to be challenging, especially when CD affects another region.

Presentation of case

A 51-year old male underwent resection of a malignant melanoma. Further staging revealed an unclear abdominal mass located in the mesentery with close contact to small intestine. Under the assumption of metastasis, complete tumor removal including intestine resection and anastomosis was performed. Both, operation and postoperative phase proved uncomplicated. Surprisingly, however, histology revealed a benign lymphoproliferative disorder, CD.

Discussion

There are several differential diagnoses for abdominal soft tissue tumor, such as: gastrointestinal stromal tumor, sarcoma, lymphoma, or metastasis. In reference to the resected melanoma described above, metastasis was assumed with subsequent oncological resection. Both, the reliable detection of CD as well as the exclusion of malignant disease (e.g. lymphoma) can only be achieved through pathology, in that specific tests fail yet to exist. The etiology of CD remains barely understood and based upon few cases reported complete surgical resection is recommended. However, the common form is meant to be benign.

Conclusion

The potential diagnosis of CD should be made more common to surgeons, especially in completely asymptomatic patients and non-superficial lesions, whereby close follow-up examination might be offered to patients.

Physical plasma-treated saline promotes an immunogenic phenotype in CT26 colon cancer cells in vitro and in vivo

Metastatic colorectal cancer is the fourth most common cause of cancer death. Current options in palliation such as hyperthermic intraperitoneal chemotherapy (HIPEC) present severe side effects. Recent research efforts suggested the therapeutic use of oxidant-enriched liquid using cold physical plasma. To investigate a clinically accepted treatment regimen, we assessed the antitumor capacity of plasma-treated saline solution. In response to such liquid, CT26 murine colon cancer cells were readily oxidized and showed cell growth with subsequent apoptosis, cell cycle arrest, and upregulation of immunogenic cell death (ICD) markers in vitro. This was accompanied by marked morphological changes with re-arrangement of actin fibers and reduced motility. Induction of an epithelial-to-mesenchymal transition phenotype was not observed. Key results were confirmed in MC38 colon and PDA6606 pancreatic cancer cells. Compared to plasma-treated saline, hydrogen peroxide was inferiorly toxic in 3D tumor spheroids but of similar efficacy in 2D models. In vivo, plasma-treated saline decreased tumor burden in Balb/C mice. This was concomitant with elevated numbers of intratumoral macrophages and increased T cell activation following incubation with CT26 cells ex vivo. Being a potential adjuvant for HIPEC therapy, our results suggest oxidizing saline solutions to inactivate colon cancer cells while potentially stimulating antitumor immune responses.

Cold Physical Plasma Selectively Elicits Apoptosis in Murine Pancreatic Cancer Cells In Vitro and In Ovo

BACKGROUND/AIM

Poor prognosis of pancreatic cancer has remained almost unchanged in recent years. Cold physical plasma was suggested as an innovative anticancer strategy, but its selective killing activity of malignant over non-malignant cells has only partially been explored. The present study aimed at exploring the effect of cold physical plasma on cellular viability.

MATERIALS AND METHODS

Induction of cell death and apoptosis by cold physical plasma was investigated in murine PDA6606 pancreatic cancer cells and primary murine fibroblasts in vitro (2D and 3D cultures) and in ovo.

RESULTS

Plasma increased apoptosis in PDA6606 to a significantly higher extent compared to fibroblasts. Antioxidants abrogated these effects, suggesting a prime role of reactive oxygen species in plasma-induced apoptosis. Plasma increased apoptosis of 3D PDA6606 multicellular spheres grown in vitro and in ovo, to significantly higher rates compared to that of fibroblasts, with minimum in ovo inflammation or necrosis observed by hematoxylin and eosin staining (H&E).

CONCLUSION

These data support the future intra-operative application of cold physical plasma for the treatment of microscopic residual tumor tissue after surgical resection.

Non-thermal plasma-treated solution demonstrates antitumor activity against pancreatic cancer cells in vitro and in vivo

Pancreatic cancer is associated with a high mortality rate. In advanced stage, patients often experience peritoneal carcinomatosis. Using a syngeneic murine pancreatic cancer cell tumor model, the effect of non-thermal plasma (NTP) on peritoneal metastatic lesions was studied. NTP generates reactive species of several kinds which have been proven to be of relevance in cancer. In vitro, exposure to both plasma and plasma-treated solution significantly decreased cell viability and proliferation of 6606PDA cancer cells, whereas mouse fibroblasts were less affected. Repeated intraperitoneal treatment of NTP-conditioned medium decreased tumor growth in vivo as determined by magnetic resonance imaging, leading to reduced tumor mass and improved median survival (61 vs 52 days; p < 0.024). Tumor nodes treated by NTP-conditioned medium demonstrated large areas of apoptosis with strongly inhibited cell proliferation. Contemporaneously, no systemic effects were found. Apoptosis was neither present in the liver nor in the gut. Also, the concentration of different cytokines in splenocytes or blood plasma as well as the distribution of various hematological parameters remained unchanged following treatment with NTP-conditioned medium. These results suggest an anticancer role of NTP-treated solutions with little to no systemic side effects being present, making NTP-treated solutions a potential complementary therapeutic option for advanced tumors.