Microbiological and ultrastructural evaluation of bacteriophage 191219 against planktonic, intracellular and biofilm infection with Staphylococcus aureus.

Infections of orthopaedic implants, such as fracture fixation devices and total-joint prostheses, are devastating complications. Staphylococcus aureus (S. aureus) is a predominant pathogen causing orthopaedic-implant biofilm infections that can also internalise and persist in osteoblasts, thus resisting antibiotic therapy. Bacteriophages are a promising alternative treatment approach. However, data on the activity of bacteriophages against S. aureus, especially during intracellular growth, and against in vivo biofilm formation on metals are scarce. Therefore, the present study evaluated the in vitro efficacy of S. aureus bacteriophage 191219, alone as well as in combination with gentamicin and rifampicin, to eradicate S. aureus strains in their planktonic stage, during biofilm formation and after internalisation into osteoblasts. Further, the invertebrate model organism Galleria mellonella was used to assess the activity of the bacteriophage against S. aureus biofilm on metal implants with and without antibiotics. Results demonstrated the in vitro efficacy of bacteriophage 191219 against planktonic S. aureus. The phage was also effective against in vitro S. aureus biofilm formation in a dose-dependent manner and against S. aureus internalised in an osteoblastic cell line. Transmission electron microscopy (TEM) analysis showed bacteriophages on S. aureus inside the osteoblasts, with the destruction of the intracellular bacteria and formation of new bacteriophages. For the Galleria mellonella infection model, single administration of phage 191219 failed to show an improvement in survival rate but appeared to show a not statistically significant enhanced effect with gentamicin or rifampicin. In summary, bacteriophages could be a potential adjuvant treatment strategy for patients with implant-associated biofilm infections.

New quantitative automated model to simulate bacterial dissemination in human tissue during irrigation of contaminated wounds.

This study presents a simple and cost-effective model using microparticles to simulate the bacterial distribution pattern in soft tissue after low- and high-pressure irrigation. Silica coated iron microparticles [comparable diameter (1 µm) and weight (0.8333 pg) to Staphylococcus aureus] were applied to the surface of twenty fresh human muscle tissue samples in two amputated lower legs. Particle dissemination into deep tissue layers as an undesired side effect was investigated in four measuring fields as positive control (PC) as well as after performing pulsatile high-pressure (HP, 8 measuring fields) and low-pressure flushing (LP, 8 measuring fields). Five biopsies were taken out of each measuring field to get a total number of 100 biopsies. After histological and digital image processing, the specimens were analysed, and all incomplete sections were excluded. A special detection algorithm was parameterised using the open source bioimage analysis software QuPath. The application of this detection algorithm enabled automated counting and detection of the particles with a sensitivity of 95 % compared to manual counts. Statistical analysis revealed significant differences (p < 0.05) in our three different sample groups: HP (M = 1608, S = 302), LP (M = 2176, SD = 609) and PC (M = 4011, SD = 686). While both HP and LP flushing techniques are able to reduce the number of bacteria, a higher effectiveness is shown for HP irrigation. Nevertheless, a challenge for the validity of the study is the use of dead tissue and therefore a possible negative influence of high-pressure irrigation on tissue healing and further dispersion of particles cannot be evaluated.

[Skin ulcerations due to CINCA syndrome and its successful treatment with prostaglandin E1]. / Kutane Ulzerationen bei CINCA­Syndrom und ihre erfolgreiche Behandlung durch Prostaglandin E1.

Chronic infantile neurological cutaneous and articular syndrome (CINCA) is a disorder with a defect in the CIAS1 (NLRP3) gene and the altered gene product cryopyrin leads to inflammasome activation with increased IL-1beta synthesis. The activation pathway of the transcription factor NF-κB is also affected, which plays a role in angiogenesis. With respect to the angiogenesis stimulating ability of prostaglandin E1, we treated a female patient with CINCA syndrome and conventionally non-responsive skin ulcers with prostaglandin E1 infusions (6 µg/kg bw/24 h/5 day) followed by wound healing lasting over 3 weeks. After 1 year of periodic infusions, the skin defects were permanently closed.

[Differential diagnosis of granulomatous diseases]. / Differenzialdiagnose granulomatöser Erkrankungen.

Despite advances in the understanding of the pathophysiology, granulomatous diseases remain a diagnostic challenge for the clinician as well as for the pathologist. However, establishing the correct diagnosis of these diseases is a crucial prerequisite of targeted therapy. It is particularly essential to distinguish between an infectious and a non-infectious cause, since anti-infectious and anti-inflammatory or immunosuppressive approaches are opposing. Failure to establish the correct diagnosis can lead to adverse consequences for the patient. An interdisciplinary approach and a critical assessment of clinical, laboratory-chemical, microbiological, imaging, and anatomical-pathological findings are crucial for the evaluation of granulomatous disorders. This overview summarizes important landmarks and their value in the interplay of arriving at the correct diagnosis.

Biocompatibility of polyurethane-coated breast implants: A histological comparison of implant capsules.

BACKGROUND: Biocompatibility describes the influence of materials on their biological environment. Implant material in the human body can cause a foreign body reaction and the formation of a capsule around the foreign material. Since capsular formation is the most frequent issue after breast-implant insertion, knowledge and awareness of biocompatibility is crucial, especially since worldwide, breast augmentation continues to be the most popular plastic surgery, with over 1.6 million procedures performed in 2020, according to surveys by the International Society of Aesthetic Plastic Surgery (ISAPS). MATERIAL AND METHODS: This study includes 80 capsular samples of female patients who underwent revision surgery after breast-implant insertion at the University Hospital Regensburg. Capsules of breast implants with different surface structures (smooth, textured and polyurethane-coated) and shapes (round-shaped, anatomically-shaped) were analyzed histologically after hematoxylin-eosin-staining in respect to capsular thickness and layer formation. RESULTS: Capsular thickness and layering showed a statistically significant difference between polyurethane-coated and smooth as well as polyurethane-coated and textured implants. Capsules around polyurethane-coated implants presented greater thickness. However, the difference between smooth and textured implants was not statistically significant. Furthermore, the shape of the implants also indicated a statistically significant difference in capsular thickness. Implants of anatomical shape resulted in a thinner capsule than round-shaped breast-implants. CONCLUSION: In conclusion, this study demonstrated a thicker capsule around polyurethane-coated breast implants and no difference in capsular thickness between smooth and textured breast implants. Anatomically shaped breast-implants presented a thinner capsule than round shaped breast-implants.

PET lung ventilation/perfusion imaging using (68)Ga aerosol (Galligas) and (68)Ga-labeled macroaggregated albumin.

Pulmonary imaging using ventilation/perfusion (V/P) single-photon emission tomography (V/P scan) with Tc-99m-labeled radiotracers is a well-established diagnostic tool for clinically suspected pulmonary embolism (PE). Ga-68 aerosol (Galligas) and Ga-68-labeled macroaggregated albumin (MAA) are potential tracers for positron emission tomography (PET) lung V/P imaging and could display an advantage over conventional V/P scans in terms of sensitivity and specificity. After radiochemical and animal studies, the clinical applicability of Ga-68 aerosol (Galligas) and Ga-68-labeled MAA was investigated in an exploratory study in patients with clinical suspicion of PE. PET scans were acquired using a 16-slice Gemini TF positron emission tomography/computed tomography (PET/CT) scanner. The acquisition protocol included low-dose computed tomography (CT) for attenuation correction (AC). Dosimetry calculations and continuative phantom measurements were performed. Structural analyses showed no modification of the particles due to the labeling process. In addition, in vitro experiments showed stability of Ga-68 MAA in various media. As expected, Ga-68-labeled human serum albumin microspheres (HSAM) were completely retained in the lung of the animals. In clinical use, PET lung ventilation and perfusion imaging using Ga-68 aerosol (Galligas) and Ga-68-labeled MAA was successful in all cases. In one case a clinically suspected PE could be detected and verified. The administered activity of Ga-68 aerosol (Galligas) and Ga-68-labeled MAA may be reduced by more than 50%, resulting in comparable radiation exposure to conventional V/P scans. In conclusion, Ga-68 aerosol (Galligas) and Ga-68-labeled MAA are efficient substitutes for clinical use and could be an interesting alternative with high accuracy for lung V/P imaging with Tc-99m-labeled radiotracers, especially in times of Mo-99 shortages and increasing use and spread of PET/CT scanners and Ga-68 generators, respectively.

Intercomparison of inductively coupled plasma mass spectrometry, quantitative neutron capture radiography, and prompt gamma activation analysis for the determination of boron in biological samples.

Boron determination in blood and tissue samples is a crucial task especially for treatment planning, preclinical research, and clinical application of boron neutron capture therapy (BNCT). Comparison of clinical findings remains difficult due to a variety of analytical methods, protocols, and standard reference materials in use. This paper addresses the comparability of inductively coupled plasma mass spectrometry, quantitative neutron capture radiography, and prompt gamma activation analysis for the determination of boron in biological samples. It was possible to demonstrate that three different methods relying on three different principles of sample preparation and boron detection can be validated against each other and yield consistent results for both blood and tissue samples. The samples were obtained during a clinical study for the application of BNCT for liver malignancies and therefore represent a realistic situation for boron analysis.

[Chronic eyelid oedema and rosacea (Morbus Morbihan): diagnostic and therapeutic challenges]. / Chronisches Lidödem assoziiert mit Rosazea (Morbus Morbihan): Differenzialdiagnostische Schwierigkeiten und Therapieoptionen.

BACKGROUND: Morbus Morbihan is a rare complication of rosacea, consisting of a persistent lymphoedema of the upper part of the face. It has typically a chronic course, unspecific histopathological findings and an extreme refractoriness to therapy. PATIENTS AND METHODS: Between February 2008 and January 2010, 5 patients with Morbus Morbihan were observed at the Department of Ophthalmology of the University Medical Centre Mainz. In the present cohort study, we describe the clinical, laboratory and histological findings that led to the diagnosis. The course of the affection and the results of different therapeutic options are also reported. RESULTS: Each patient underwent a complete ophthalmological examination, as well as general and dermatological consultations. All patients showed facial skin alterations typical for rosacea. 4 out of 5 subjects underwent a lid biopsy to confirm the diagnosis of Morbus Morbihan, one patient refused it. Initial treatment consisted of various systemic and local medical therapies, however, with poor success. One patient had intravenous therapy with corticosteroids elsewhere with no effect. We treated 3 cases with intralesional triamcinolone injections with good results. 2 patients underwent upper lid blepharoplasty. Results of surgery remained stable also due to manual lymph drainage and intralesional injections of triamcinolon. No complications or side effects were seen in patients treated with triamcinolone. CONCLUSIONS: Morbus Morbihan can be diagnosed only after excluding other conditions leading to chronic lid swelling. In our series, good results were achieved with intralesional injection of triamcinolone. Surgery also led to relevant improvements for a long period (13 months), with some adjuvant therapy. The treatment of chronic eyelid oedema associated with rosacea remains a challenge for the ophthalmologist and the oculoplastic surgeon.

Expression of E-selectin and vascular cell adhesion molecule-1 in so-called 'negative' appendices: first results to support the pathological diagnosis in borderline cases.

BACKGROUND: Since the rate of histologically 'negative' appendices still ranges between 15 and 20%, appendicitis in 'borderline' cases remains a challenging disease. As previously described, cell adhesion molecule expression correlates with different stages of appendicitis. Therefore, it was of interest to determine whether the 'negative' appendix correlated with the absence of E-selectin or vascular cell adhesion molecule-1 (VCAM-1). METHODS: Nineteen grossly normal appendices from a series of 120 appendectomy specimens from patients with suspected appendicitis were analysed in frozen sections for the expression of E-selectin and VCAM-1. As control, 5 normal appendices were stained. RESULTS: This study showed a coexpression of E-selectin and VCAM-1 in endothelial cells in early and recurrent appendicitis. In patients with symptoms for less than 6 h, only E-selectin was detected. Cases with fibrosis and luminal obliteration were only positive for VCAM-1. In cases of early appendicitis with symptoms of less than 6 h duration, a discordance between histological and immunohistochemical results was found. CONCLUSIONS: This report indicates that E-selectin and VCAM-1 expression could be useful parameters in the diagnosis of appendicitis in borderline cases.

[In vitro trials with single and co-cultures of osteoblasts and endothelial cells : evaluation of new biomaterials for bone reconstruction and regeneration]. / Bewertung von neuartigen Biomaterialien zum Zweck der Knochenrekonstruktion und -regeneration : In-vitro-Versuche mit Mono- und Kokulturen von Osteoblasten und Endothelzellen.

Many different types of bone substitute biomaterials are being developed for different applications in the body. The current dogma is that if osteoblasts and endothelial cells grow and exhibit normal cell functions on these materials in vitro as single cultures or in co-cultures, then the biomaterials are suitable for implantation for bone reconstruction and regeneration. Generally, only in vivo animal studies will prove whether this is the case. However, in vitro studies offer a good pre-screening and selection basis to evaluate the biocompatibility of novel biomaterials prior to animal studies. Multicell type co-culture systems hold a great promise for the future.

[Tissue engineering of cartilage and bone : growth factors and signaling molecules]. / Wachstumsfaktoren und Signalmoleküle zur Anwendung im "Tissue Engineering" : Targeting und innovative Releasesysteme.

Modern tissue engineering concepts integrate cells, scaffolds, signaling molecules and growth factors. In tissue engineering of cartilage, the growth plate of the long bone represents an interesting, well-organized developmental structure, with a spatial distribution of chondrocytes in different proliferation and differentiation stages embedded in a scaffold of extracellular matrix components. The proliferation and differentiation of these chondrocytes is regulated by various hormonal and paracrine factors. This article discusses some important growth factors in the process of endochondral ossification and demonstrates how this information could be translated into a controlled release system for different tissue engineering strategies.

Perspectives for the tissue engineering of cartilage from a biological and biomaterial point of view.

Tissue engineering has become a fast growing interdisciplinary branch of research at the interface between life and engineering sciences with important clinical end-points. In this context the regeneration of articular cartilage represents an exciting challenge since hyaline cartilage has a limited capacity for self-repair. Today the use of different scaffold materials combined with in vitro expanded chondrocytes and signalling molecules poses great hopes for an optimal treatment of articular cartilage defects. However, until today the optimal construct of scaffolds, cells and signalling molecules has not yet been found. Since repair and regeneration recapitulate in part ontogenetic processes, the present paper summarizes the regulative mechanisms of endochondral ossification in the growth plate of the long bones to identify possible new signalling molecules for the improvement of tissue engineering-based solutions in the treatment of cartilage defects. The growth plate represents a highly organized structure of chondrocytes and extracellular matrix components in distinguishable proliferation and differentiation stages. It is regulated by various paracrine and hormonal factors. In a second part we present actual trends in scaffold design based on synthetic polymers and natural polymers, stressing their potential use in the regeneration of cartilage defects from the point of view of bioactivity and biocompatibility. In conclusion, both new signalling molecules from basic research and innovative scaffold materials with variable physico-chemical properties open up new and interesting perspectives for the research in optimized tissue engineeredbased therapeutic strategies to treat cartilage defects.

FDG-PET in the initial staging of squamous cell oesophageal carcinoma.

UNLABELLED: Squamous cell oesophageal carcinoma is the most common carcinoma of the oesophagus worldwide. The tumour stage as most important prognostic factor determines the clinical management. AIM: of this study was to evaluate the value of FDG-PET 1. in imaging the primary tumour and 2. in N- and M-staging of squamous cell oesophageal carcinoma. PATIENTS, METHODS: In 20 patients with histological proven squamous cell carcinoma of the upper and middle oesophagus, FDG-PET was performed in standard technique prior to therapy. FDG uptake in the primary was determined by calculation of the SUVmax. NM-staging due to PET findings was performed as designated by the AJCC/UICC group classification and was compared with pathological and clinically based staging. Sensitivities, specificities and accuracies were calculated. RESULTS: In 19 of 20 patients, primary squamous cell oesopohageal carcinoma was detected by FDG-PET findings with a maximum SUV of 12.5 (mean) +/- 5.1 (median 11.5; range 4.8-23.8). One carcinoma in situ was missed. The sensitivity of FDG-PET in imaging the primary tumour was 96%. The sensitivities, specificities and accuracies were 20%, 100%, 58% for N-staging, and 60%, 86% and 93% for M-staging. PET findings caused changes of therapy in 5% (1 patient). CONCLUSIONS: FDG-PET was excellent in imaging the primary of squamous cell oesophageal carcinoma in stage T1-T4 and was efficient in M-staging. The low sensitivity in N-staging is of inferior clinical importance. The efficacy of FDG-PET seems to be not significantly be influenced by the histological subtype of oesophageal carcinoma.

Tissue engineered pre-vascularized buccal mucosa equivalents utilizing a primary triculture of epithelial cells, endothelial cells and fibroblasts.

Artificial generated buccal mucosa equivalents are a promising approach for the reconstruction of urethral defects. Limiting in this approach is a poor blood vessel supply after transplantation, resulting in increased morbidity and necrosis. We generated a pre-vascularized buccal mucosa equivalent in a tri-culture of primary buccal epithelial cells, fibroblasts and microvascular endothelial cells, using a native collagen membrane as a scaffold. A successful pre-vascularization and dense formation of capillary-like structures at superficial areas was demonstrated. The lumen size of pre-formed blood vessels corresponded to the capillary size in vivo (10-30 µm). Comparing native with a highly cross-linked collagen membrane we found a distinct higher formation of capillary-like structures on the native membrane, apparently caused by higher secretion of angiogenic factors such as PDGF, IL-8 and angiopoietin by the cells. These capillary-like structures became functional blood vessels through anastomosis with the host vasculature after implantation in nude mice. This in vitro method should result in an accelerated blood supply to the biomaterial with cells after transplantation and increase the succes rates of the implant material.

Production of superoxide by human malignant melanoma cells.

Metastasis is a complicated multi-step process involving interactions between tumour cells, the extracellular matrix and the vessel walls. Experimental observations suggest that leucocyte migration and function could be a suitable model in order to understand tumour cell dissemination. In the present report we show and quantify the production of free radicals by human malignant melanoma cells (St-ml12) by means of a spectrophotometrical method, using an enzyme immunoassay reader. Endothelial cells and activated polymorphonuclear leucocytes were used as controls. Melanoma cells without stimulants produced large amounts of superoxide anion at an increasing rate in relation to time, which could be inhibited by superoxide dismutase. Production of hydrogen peroxide was minimal. The endothelial cells produced a negligible amount, in contrast to the activated polymorphonuclear leucocytes, which released large quantities of both free radicals. A rapid assay to analyse the production of free radicals by tumour cells is presented here. Using this, we demonstrated that melanoma cells produce superoxide anions, supporting previous observations which implicate superoxide anion in the mechanism of metastasis.

Boron determination in liver tissue by combining quantitative neutron capture radiography (QNCR) and histological analysis for BNCT treatment planning at the TRIGA Mainz.

The typical primary malignancies of the liver are hepatocellular carcinoma and cholangiocarcinoma, whereas colorectal liver metastases are the most frequently occurring secondary tumors. In many cases, only palliative treatment is possible. Boron neutron capture therapy (BNCT) represents a technique that potentially destroys tumor tissue selectively by use of externally induced, locally confined secondary particle irradiation. In 2001 and 2003, BNCT was applied to two patients with colorectal liver metastases in Pavia, Italy. To scrutinize the rationale of BNCT, a clinical pilot study on patients with colorectal liver metastases was carried out at the University of Mainz. The distribution of the (10)B carrier (p-borono-phenylalanine) in the liver and its uptake in cancerous and tumor-free tissue were determined, focusing on a potential correlation between the uptake of p-borono-phenylalanine and the biological characteristics of cancerous tissue. Samples were analyzed using quantitative neutron capture radiography of cryosections combined with histological analysis. Methodological aspects of the combination of these techniques and results from four patients enrolled in the study are presented that indicate that the uptake of p-borono-phenylalanine strongly depends on the metabolic activity of cells.

Reconstruction of peritoneal-like structure in three-dimensional collagen gel matrix culture.

The peritoneum is a serous membrane consisting of different kinds of cells and extracellular matrix components (ECM). The aim of the present study was to develop a three-dimensional (3D) in vitro culture system for possible investigation of pathological conditions of the peritoneum. Human omental mesothelial cells (MC) and endothelial cells from the umbilical vein (EC) were cultivated either on (MC) or in (EC) a preformed type I collagen matrix. In 3D culture mesothelial cells showed their phenotypical in vivo characteristics and the synthesis of a new basal membrane (BM). Endothelial cells developed vessel-like structures, produce a BM and express E-selectin after TNF-alpha stimulation. This 3D culture system presents extended possibilities for analyzing mesothelial and endothelial cell behavior as well as the cell-cell and cell-matrix interactions involved in several pathological processes in the peritoneum.

PECAM-1 expression in human mesothelial cells: an in vitro study.

Mesothelial cells are actively involved in inflammatory processes by expressing a set of cell adhesion molecules (CAMs). Transmigration of leukocytes into inflamed tissues requires a chemotactic stimulus and engagement of platelet-endothelial cell adhesion molecule-1 (PECAM-1). To investigate the kinetics involved in peritonitis, pure cultures of mesothelial cells are necessary. In previous studies, we have found that human mesothelial cells (HOMES) show a weak constitutive expression of PECAM-1, which cannot be further stimulated by cytokines. It is known that all serous cavities and body fluids contain numerous macrophages which strongly express this adhesion molecule. To identify the cells responsible for the expression of PECAM-1, mesothelial cells freshly obtained from omental tissue were isolated using PECAM-1-conjugated magnetic beads by cell sorting. For these studies, the negative as well as the positive fraction of isolated cells were used. As a control, freshly isolated monocytes were studied. Cell cultures were characterized by light and electron microscopy, as well as immunocytochemistry. The negative cell fraction was cultivated and stimulated for different times with tumor necrosis factor-alpha (30 and 300 U/ml), interleukin-1 beta (10 and 100 U/ml) and interferon-gamma (500 U/ml) and PECAM-1 expression was analyzed by a comparative quantitative cell enzyme immunoassay (EIA). The positive cell fraction was treated in the same manner. Both fractions of isolated cells showed strong positivity for cytokeratins 8, 18, 7 and 19, as well as vimentin. CD68, a monocyte marker, was not detected on mesothelial cells. In addition, EIA analysis confirmed the constitutive expression of PECAM-1 obtained from previous studies. This expression on HOMES was not inducible, irrespective of the type and concentration of cytokine studied. These data confirm PECAM-1 expression on mesothelial cells obtained from human omental tissue and suggest a critical role in transmigration of leukocytes during peritoneal inflammation.

Differential expression of cell adhesion molecules in inflamed appendix: correlation with clinical stage.

The diagnosis of 'early inflamed', 'recurrent' or 'sub-acute' appendicitis is often difficult and accompanied by controversies between clinical data, histological findings, and their interpretation. The expression of the intercellular cell adhesion molecule-1 (ICAM-1), the vascular cell adhesion molecule-1 (VCAM-1), and E-selectin has been studied in 61 appendicectomy specimens for possible use as a diagnostic tool. This study demonstrates a different expression of CAM by endothelial (EC) and mesothelial cells (MC) in the various stages of appendicitis, with early E-selectin and ICAM-1 expression in EC, followed by VCAM-1 in EC and MC. Appendices from patients with prolonged clinical symptoms defined by clinicians as 'chronic' appendicitis showed VCAM-1 expression and occasionally weak expression of E-selectin in EC. In several cases, discrepancies were found between the pre-operative 'clinical' diagnosis, the histomorphological findings, and the immunohistological results. In this context, the expression of E-selectin and VCAM-1 in comparison with the histological features has potential significance in the diagnosis of 'early acute', 'sub-acute' or 'recurrent' appendicitis. In addition, a correlation was demonstrated between the histological stages of appendicitis and the kinetics of CAM expression. The study also indicates that the time course of E-selectin expression in vivo is longer than is suggested from in vitro data.